LIQUID PUMPING CASSETTES AND ASSOCIATED PRESSURE DISTRIBUTION MANIFOLD AND RELATED METHODS

Abstract

A fluid handling cassette comprising a plurality of diaphragm valves and pumps is configured to have its actuating ports located along a thin or narrow edge of the cassette; actuating channels within the cassette lead from the actuating ports to the actuating chambers of the valves and pumps in a space between the plates comprising the cassette; the individual plates have a nominal thickness sufficient to provide a rigid roof for the actuating channels, yet thin enough to minimize the overall thickness of the cassette; the cassette can be plugged into or unplugged from an actuating receptacle or manifold by its narrow edge; a plurality of such cassettes can be stacked together or spaced apart to form a cassette assembly, providing a convenient way to install and remove the cassette assembly from its actuating receptacle;The arrangement allows an improved way of connecting a complex cassette assembly to its associated pressure distribution manifold without the use of a plurality of flexible connecting tubes between the two.

Description

LIQUID PUMPING CASSETTES AND ASSOCIATED PRESSURE DISTRIBUTION MANIFOLD AND RELATED METHODS FIELD OF THE INVENTION This disclosure relates generally to improvements in the design and construction of fluid pumping or mixing cassettes, cassette assemblies, their constituent parts, and associated devices. BACKGROUND OF THE INVENTION Liquid handling cassettes comprising diaphragm pumps and / or valves can be fluidly actuated (hydraulic or pneumatic). In some examples, a cassette is designed to be fluidly connected to a pneumatically actuated manifold having electromechanical valves that selectively distribute positively or negatively pressurized gas or air to the cassette. A programmable electronic controller can be used to control the electromechanical valves to selectively supply positive or negative pneumatic pressure to various pumps or valves in the cassette in a predetermined manner. Some fluid handling cassettes may have a substantially flat shape, with a wide side flanked by a thin or narrow side that is relatively less thick than the overall dimensions of the cassettes wide side. Liquid inlet and outlet ports can be incorporated into the rim or thin side of the cassette. But in many of these devices, the actuation ports for the cassette have been located on the face or wide side of the cassette directly over the actuation chambers of the pumps or valves being controlled. This generally provides the shortest route for an actuation channel in the cassette from an external actuation port of the cassette to the actuation chamber and diaphragm of a pump or valve in the cassette. Furthermore, in many cases, the pumping stations or regions or valves of the cassette, comprising the actuation chamber on one side or the liquid transport chamber on the opposite side, may be defined by spheroidal or hemi-spherical chamber walls. spheroids that extend above the plane of the cassette face, making the overall cassette thicker than is desirable in some applications. In other cases, a pump module may comprise a set of blocks sandwiched or laminated together, with the pneumatic actuation channels or fluid channels embedded within one or more of the blocks. This arrangement can also result in a greater overall thickness of the device than is desirable for certain applications. Some applications may require a plurality of frAzn Ln / nznz / E / Yi fluid handling cassettes to be mounted side by side in tight spaces. In these cases, it may be desirable to place a number of cassettes adjacent to each other, stack them against each other, or at least place their wide sides facing each other in close proximity. It may be particularly desirable to reduce or minimize the thickness of the individual cassettes that make up these assemblies. It may be advantageous to arrange for a pump cassette to be directly connected to its associated pressure distribution manifold (eg, a manifold that selectively supplies pneumatic pressure to the pump cassette under control of an electronic controller). In previously described embodiments of a hemodialysis system using self-contained pneumatically driven pump cassettes, the pump cassettes were connected to a corresponding pneumatic manifold via flexible tubing, which has led to significant challenges during assembly and in operation. If a pump cassette can be located close to its associated manifold, a direct plug-in connection between the two would have substantial advantages. In these circumstances, it would be particularly advantageous to have a compact manifold that allows direct interface with a pump cassette, arranged in such a way as to allow the cassette or cassette assembly to be plugged in and out of the manifold actuation ports with minimal effort. In the design and operation of a pneumatic distribution manifold, the ability to use binary pressure control valves instead of continuously variable orifice valves would also provide significant advantages in both cost and reliability. But in this case, controlling the supply of pressure to individual pumps or cassette valves using binary pressure control valves poses additional challenges that must be overcome. An electronic controller robust enough to use control algorithms to control the frequency and duration of binary valve actuation can be programmed to achieve precise control of associated pneumatically actuated valves or pumps. BRIEF DESCRIPTION OF THE INVENTION In one embodiment, a pump and / or valve cassette has a relatively flat shape, with a broad side flanked by a thinner narrow side or edge. It comprises an intermediate plate positioned between two external plates: a first external plate facing a first side of the intermediate plate and a second external plate facing a second opposite side of the intermediate plate. The first outer plate is spaced from the intermediate plate to form a first space between plates. The second outer plate is spaced from the intermediate plate to form a second space between plates. The thickness of the first and second outer plates is limited to a thickness sufficient to impart rigidity to the plate and provide a Ln / nznz / E / Yi Ln / nznz / E / Yi sealing surface against opposite channel walls on each side of the intermediate plate. In some embodiments, the thickness of each outer plate, together with the thickness of the intermediate plate between them, define the overall thickness of the cassette. In other embodiments, the fluid inlet and outlet ports protrude from an outer face of the cassette, increasing the overall thickness of the cassette. The cassette may include one or more pumping stations or regions and two or more valve stations or regions. The number of pump or valve stations and their size can determine the overall dimensions of the wide side of the cassette. The stroke volume of a shipboard pump is a function of the diameter of a pump station and its associated diaphragm and the depth of excursion of the diaphragm defined by the depth of the intermediate plate channel walls, and this in turn will determine the thickness of the cassette as well as its wide side dimension. For any given pump or valve station, the intermediate plate comprises an actuating side and an opposite liquid side, with the actuating side supporting a pump or valve diaphragm. The actuation channels in the cassette to the respective pump or valve stations may be contained within the intermediate plate channels of the first interplate gap and run generally parallel to the broad side of the cassette. The fluid channels in the cassette may be contained within the intermediate plate channels of the second interplate gap and generally also run parallel to the broad side of the cassette, except in some cases where the fluid channels connect to an inlet or outlet. of the cassette. In this arrangement, the first and second outer plates function primarily to provide a ceiling or boundary wall over the respective actuation and liquid transport valve or pump regions. In one embodiment, a fluid handling cassette may comprise an intermediate plate positioned between a first plate and a second plate, the plates having a length, a width, and a plate thickness, a first side of the intermediate plate opposite the first plate and a second side of the intermediate plate opposite the second plate. The first plate is spaced from the intermediate plate defining a width of a first space between plates, and the second plate is spaced from the intermediate plate defining a width of a second space between plates. A cassette edge has a cassette thickness defined by the thickness of each plate plus the width of the first and second gaps between plates, and a cassette face is defined by the length and width of the first or second plate. The intermediate plate may comprise a pump station defined by a pump diaphragm and the first side of the intermediate plate, said pump diaphragm seated against the first side of the intermediate plate and with an excursion interval defined by the width of the first gap. of the intermediate plate. A pump actuation channel runs parallel to the face of the cassette in the first interplate gap connecting a pump actuation chamber bounded by the first plate and the pump diaphragm with a cassette pump actuation port located within the first gap between plates in a Ln / nznz / E / Yi first edge of the cassette. First and second pump fluid ports in the pump station may fluidly connect respective first and second fluid channels in the second gap between plates to a pumping chamber defined by the pump diaphragm and the first side of the pump. intermediate plate. A pump fluid port in the pump station can fluidly connect a fluid channel in the second interplate gap with a pumping chamber defined by the pump diaphragm and the first side of the intermediate plate. Alternatively, there may be an opening in the middle plate in the pump station, the opening allowing the pump diaphragm to move from the first plate to the second plate when actuated by positive or negative pressure supplied through the actuation channel. of the bomb. The plates (first, intermediate plate, and second) are generally insufficiently thick to allow the fluid or actuation channels to run within the plates in a direction parallel to the face of the cassette. A fluid channel may run in the second interplate space and connect fluidly to a pumping chamber defined by the pump diaphragm and the first side of the intermediate plate, the connection being made through one or more fluid ports. fluid from the pump in the intermediate plate so that the fluid channel runs parallel to the face of the cassette in the second gap connecting the pumping chamber with a fluid port of the cassette located within the second gap in the intermediate plate. first edge or a second edge of the cassette. In one embodiment, a fluid handling cassette may comprise an intermediate plate positioned between a first plate and a second plate, the plates having a length, a width, and a plate thickness, a first side of the intermediate plate opposite the first plate and a second side of the intermediate plate opposite the second plate. The first plate is spaced from the intermediate plate by defining a width of a first space between plates, and the second plate is spaced from the intermediate plate by defining a width of a second space between plates. A cassette edge has a cassette thickness defined by the thickness of each plate plus the width of the first and second gaps between plates, and a cassette face is defined by the length and width of the first or second plate. The intermediate plate may comprise a valve station defined by a valve diaphragm and the first side of the intermediate plate, the valve diaphragm seated against the first side of the intermediate plate and with an excursion interval defined by the width of the first intermediate plate. intermediate plate space. And a valve actuation channel may run parallel to the face of the cassette in the first interplate gap connecting a valve actuation chamber bounded by the first plate and the valve diaphragm with a valve actuation port of the cassette located within the first interplate gap at a first edge of the cassette. First and second valve fluid ports in the valve station may fluidly connect respective first and second fluid channels in the second Ln / nznz / E / Yi plate spacing to a valve fluid chamber defined by the valve diaphragm and the first side of the intermediate plate. One or both of the valve fluid ports may comprise a raised valve seat to seal the valve diaphragm over the first or second valve fluid ports when positive pressure is applied to the valve diaphragm through the actuation channel. from valvule. The first fluid channel is fluidly isolated from the second fluid channel through the fluid ports of the first and second valves. A fluid channel can run in the second interplate space and connect fluidly to a fluid chamber of the valve defined by the valve diaphragm and the first side of the intermediate plate, the connection being made through two fluid ports. of the valve in the intermediate plate so that the fluid channel runs parallel to the face of the cassette in the second gap connecting the fluid chamber of the valve with a fluid port of the cassette located within the second gap on the first edge or on a second edge of the cassette. In another embodiment, a fluid handling cassette may comprise an intermediate plate positioned between a first plate and a second plate, the plates having a length, a width, and a plate thickness, a first side of the intermediate plate opposite the first plate and a second side of the intermediate plate opposite the second plate. The first plate is spaced from the intermediate plate by defining a width of a first space between plates, and the second plate is spaced from the intermediate plate by defining a width of a second space between plates. A cassette edge has a cassette thickness defined by the thickness of each plate plus the width of the first and second gaps between plates, and a cassette face is defined by the length and width of the first or second plate. The intermediate plate may comprise a pump station defined by a pump diaphragm and the first side of the intermediate plate, the pump diaphragm seating against the first side of the intermediate plate and having an excursion defined by the width of the first gap. between plates. The intermediate plate may also comprise first and second valve stations, each defined by a valve diaphragm and the first side of the intermediate plate, the valve diaphragm seating against the first side of the intermediate plate and having an interval excursion defined by the width of the first gap between plates. There is a pump actuation channel for the pump station and a valve actuation channel for each of the first and second valve stations. The pump actuation channel runs parallel to the face of the cassette in the first interplate gap connecting a pump actuation chamber bounded by the first plate and the pump diaphragm with a cassette pump actuation port located within the first gap between plates at a first edge of the cassette. And each of the valve actuation channels runs parallel to the cassette face in the first interplate gap connecting a valve actuation chamber bounded by the first plate and the valve diaphragm with a valve actuation port. Ln / nznz / E / Yi cassette valve actuation located within the first gap between plates at the first edge of the cassette. There may be one inlet and outlet valve fluid port at each of the two valve stations, and one or more pump fluid ports at the pump station, each of the valve fluid ports and of the pump by fluidly connecting a fluid channel in the second interplate space with: a pumping chamber defined by the pump diaphragm and the first side of the intermediate plate, and a valve fluid chamber in each of said valve stations defined by the corresponding valve diaphragm and the first side of the intermediate plate. The fluid channel has a flow path that passes through the inlet and outlet valve fluid ports and one or more pump fluid ports so that selective actuation of the pump actuation chamber and the valve actuation chambers allow for unidirectional flow of a fluid through the fluid channel. A fluid channel can run in the second interplate space and fluidly connect to: a pumping chamber defined by the pump diaphragm and the first side of the intermediate plate, the connection is made through a fluid port on the pump in the intermediate plate, and a valve fluid chamber of each valve station, each of the valve fluid chambers being defined by the corresponding valve diaphragm and the first side of the intermediate plate, each One of the connections is made through the valve's two fluid ports in the intermediate plate, so that the fluid channel runs parallel to the face of the cassette in the second plate gap connecting the pumping chamber and each of the fluid chambers of the valve with a cassette fluid inlet port and a cassette fluid outlet port located within the second interplate space at the first or second edge of the cassette. The fluid inlet port of the cassette and the fluid outlet port of the cassette may be located on a second edge of the cassette, so that the pump actuation port of the cassette and the valve actuation port of the cassette are configured for plugging directly into a corresponding actuation receptacle external to the cassette, and so that the fluid inlet port and fluid outlet port are arranged to be connected by flexible or malleable tubing to a fluid source or destination external to the cassette . A fluid channel can run in the second interplate space and fluidly connect to: a pumping chamber defined by the pump diaphragm and the first side of the intermediate plate, the connection is made through a fluid port on the pump in the intermediate plate, and a valve fluid chamber of each valve station, each of the valve fluid chambers being defined by the corresponding valve diaphragm and the first side of the intermediate plate, each of Connections are made through the valve's two fluid ports on the intermediate plate. The fluid channel may run parallel to the face of the cassette in the second interplate gap and connect the pumping chamber and each of the valve's fluid chambers with a fluid inlet port of the valve. Ln / nznz / E / Yi cassette and a cassette fluid outlet port, the cassette fluid inlet port, and a fluid outlet port that exits the cassette through rigid conduits originating from the intermediate plate and they penetrate the face of the cassette through the first or second outer plates. In a further embodiment, a plurality of walls may be formed on the first and second sides of the intermediate plate, said walls arranged to merge with the first and second plates to form drive or fluid channels within the cassette. A first type of walls may comprise parallel walls to define drive or fluid channels, a second type of walls may comprise circumferential perimeter walls defining pump or valve actuation stations, and a third type of walls may comprise adjacent end walls. defining a termination of the channel in which a fluid port from the valve or pump enters the intermediate plate. The first plate may comprise one or more circumferential valve or pump diaphragm retainers configured to fit within the circumferential perimeter walls of the opposite middle plate defining the pump or valve actuation stations, the retainers arranged to hold a bead or peripheral flange of an associated diaphragm positioned in the intermediate plate pump or valve station. Retainers may include holes, fenestrations, or slots to allow transmission of actuation fluid or gas between the valve or pump actuation chamber surrounded by the retainer and an associated actuation channel. The first plate may comprise an elongated rib configured to be positioned within a mating actuation channel of the intermediate plate, the cross-sectional size and length of the rib arranged to adjust the volume of the actuation channel to a predetermined value between a cassette actuation port and an associated valve or pump actuation chamber. In another embodiment, a fluid handling cassette may comprise an intermediate plate positioned between a first plate and a second plate, said plates having a plate length, width, and thickness, a first side of the intermediate plate opposite the first plate and a second side of the intermediate plate opposite the second plate, the first plate is spaced from the intermediate plate by defining a width of a first plate gap, and the second plate is spaced from the intermediate plate by defining a width of a second space between plates. A cassette edge has a cassette thickness defined by the thickness of each plate plus the width of the first and second gaps between plates, and a cassette face is defined by the length and width of the first or second plate. The intermediate plate may comprise first and second valve stations, the first valve station defined by a first valve diaphragm and the first side of the intermediate plate, and the second valve station defined by a second valve diaphragm and the second side of the intermediate plate, the first valve diaphragm seated against the first side of the intermediate plate and having an interval Ln / nznz / E / Yi of excursion defined by the width of the first interplate gap, and the second valve diaphragm seated against the second side of the intermediate plate and having an excursion interval defined by the width of the second interplate gap . A first valve actuation channel for the first valve station may run parallel to the face of the cassette in the first gap, and a second valve actuation channel for the second valve station may run parallel to the face of the cassette in the second space between plates. The first valve actuation channel connects a first valve actuation chamber bounded by the first plate and the first valve diaphragm with a first valve actuation port of the cassette located within the first interplate space at a first valve actuation port. edge of the cassette, and the second valve actuation channel connects a second valve actuation chamber bounded by the second plate and the second valve diaphragm with a second valve actuation port of the cassette located within the second space between plates at the first edge of the cassette. In another embodiment, a fluid handling cassette may comprise an intermediate plate positioned between a first plate and a second plate, the plates having a length, a width, and a plate thickness, a first side of the intermediate plate opposite the first plate and a second side of the intermediate plate opposite the second plate. The first plate is spaced from the intermediate plate by defining a width of a first space between plates, and the second plate is spaced from the intermediate plate by defining a width of a second space between plates. A cassette edge has a cassette thickness defined by the thickness of each plate plus the width of the first and second gaps between plates, and a cassette face is defined by the length and width of the first or second plate. The intermediate plate may comprise a first and a second pump station, the first pump station defined by a first pump diaphragm and the first side of the intermediate plate, and the second pump station defined by a second pump diaphragm and the first side of the intermediate plate. second side of the intermediate plate, the first pump diaphragm seated against the first side of the intermediate plate and having an excursion interval defined by the width of the first interplate gap, and the second pump diaphragm seated against the second side of the intermediate plate and having an excursion interval defined by the width of the second interplate gap. A first pump actuation channel for the first pump station may run parallel to the face of the cassette in the first gap, and a second pump actuation channel for the second pump station may run parallel to the face of the cassette in the second interplate space, the first pump actuation channel connects a first pump actuation chamber bounded by the first plate and the first pump diaphragm with a first cassette pump actuation port located within the first space between the plates at a first edge of the cassette. The second pump actuation channel connects a second pump actuation chamber limited by the Ln / nznz / E / Yi second plate and second pump diaphragm with a second cassette pump actuation port located within the second plate gap at the first edge of the cassette. In another embodiment, a fluid handling cassette assembly may comprise an intermediate cassette interposed between a first outer cassette and a second outer cassette, each cassette comprising: an intermediate plate positioned between a first plate and a second plate, the plates having a a length, a width and a plate thickness, a first intermediate plate side opposite the first plate and a second intermediate plate side opposite the second plate. The first plate is spaced from the intermediate plate by defining a width of a first space between plates, and the second plate is spaced from the intermediate plate by defining a width of a second space between plates. A cassette edge has a cassette thickness defined by the thickness of each plate plus the width of the first and second gaps between plates, and a cassette face is defined by the length and width of the first or second plate. A plurality of diaphragm valves or pumps comprising valve or pump actuation chambers may be connected to actuation channels that run parallel to the face of the cassette within the first or second plate gap, and terminate in respective actuation ports of the valve or pump of the cassette at a first edge of the cassette between the first or second gap between plates. A fluid management capsule is positioned in an intercassette space between the center cassette and the first or second cassette, the capsule has a fluid connection to fluid channels in the middle, first, or second cassette via a fluid conduit. fluid penetrating the intermediate, first, or second cassette face. The first edge of the intermediate, first, and second cassettes are located on a first side of the cassette assembly such that the valve or pump actuation ports of the cassette are configured to connect to or disconnect from a cassette receptacle assembly. actuation port opposite the first side of the cassette assembly. The fluid handling capsule may comprise a diaphragm pump capsule having an actuation and fluid connection to actuation and fluid channels in the intermediate, first, or second cassette via an actuation conduit and a discharge conduit. fluid, each penetrating the face of the intermediate cassette, first or second. The diaphragm pump capsule actuation conduit may be connected to an actuation channel in a first or second interplate space of the intermediate, first, or second cassette, and has an uninterrupted connection to a cassette actuation port for the diaphragm pump capsule. diaphragm pump on the first edge of the intermediate, first or second cassette. The diaphragm pump capsule fluid conduit may be connected to a fluid channel in a first or second interplate space of the intermediate, first, or second cassette, and may be connected to a diaphragm valve in the cassette and a flow channel. The diaphragm valve actuation can be connected to a diaphragm valve cassette actuation port on the first edge of the intermediate cassette, first Ln / nznz / E / Yi or B. The fluid conduit in any of these arrangements can be rigid. A plurality of fluid handling capsules may be positioned between the intermediate cassette and the first cassette, and between the intermediate cassette and the second cassette, and the associated fluid conduits of these plurality of fluid handling capsules may be rigid to provide structural support for mounting the cassette. A cassette mounting frame can be configured to improve the structural rigidity of the cassette mounting, the cassette mounting frame comprises a rigid support plate on a second side of the cassette mounting opposite the first side of the cassette mounting, the plate support configured to engage a cassette loading apparatus in front of the actuation port receptacle. In another embodiment, a fluid handling cassette assembly may comprise: an intermediate cassette interposed between a first outer cassette and a second outer cassette, each cassette comprising an intermediate plate positioned between a first plate and a second plate, the plates having a a length, a width and a thickness of plate, a first side of the intermediate plate opposite the first plate and a second side of the intermediate plate opposite the second plate. The first plate is spaced from the intermediate plate by defining a width of a first space between plates, and the second plate is spaced from the intermediate plate by defining a width of a second space between plates. A cassette edge has a cassette thickness defined by the thickness of each plate plus the width of the first and second gaps between plates, and a cassette face is defined by the length and width of the first or second plate. A plurality of diaphragm valves or pumps may comprise valve or pump actuation chambers connected to actuation channels that run parallel to the face of the cassette within the first or second interplate gaps, and terminate in respective actuation ports of the diaphragm valve or pump. valve or pump of the cassette at a first edge of the cassette between the first or second gaps between plates. A first fluid handling capsule may be placed in an inter-cassette space between the intermediate cassette and the first or second cassette; the fluid handling capsule having a fluid connection to fluid channels in the first or second intermediate cassette via a fluid conduit penetrating the face of the first or second intermediate cassette. A second fluid handling capsule may comprise a diaphragm pump capsule having an actuation and fluid connection to the actuation and fluid channels in the intermediate, first, or second cassette via an actuation conduit and a fluid conduit. of fluid, each penetrating the face of the intermediate cassette, first or second. The first edge of the middle, first, and second cassettes may be located on a first side of the cassette assembly such that the valve or pump actuation ports of the cassette are configured to connect to or disconnect from a receptacle assembly of the cassette. actuation port opposite the first side of the cassette mount. The actuation passage of the capsule of the diaphragm pump Ln / nznz / E / Yi may be connected to an actuation channel in a first or second interplate space of said intermediate, first, or second cassette, and may have an unbroken connection to a cassette actuation port for the pump capsule of diaphragm at the first edge of said intermediate, first or second cassette. The diaphragm pump capsule fluid conduit may be connected to a fluid channel in a first or second interplate space of the intermediate, first, or second cassette, and may be connected to a diaphragm valve in the cassette and a flow channel. The diaphragm valve actuation can then be connected to a diaphragm valve cassette actuation port at the first edge of said intermediate, first or second cassette. The fluid conduit may be rigid. There may be a plurality of fluid handling receptacles between the intermediate cassette and the first cassette, and between the intermediate cassette and the second cassette, and the associated fluid conduits of these plurality of fluid handling receptacles may be rigid, providing support. frame for mounting the cassette. A cassette mounting frame can be configured to improve the structural rigidity of the cassette mounting, the cassette mounting frame comprises a rigid support plate on a second side of the cassette mounting opposite the first side of the cassette mounting, the plate support configured to engage a cassette loading apparatus in front of the actuation port receptacle. In another aspect of the invention, a manifold adapter is configured to connect a pressure distribution manifold to a liquid handling cassette assembly. A housing has a first side comprising a first set of transfer ports configured to connect to actuation output ports of the manifold, and has an opposite second side comprising a second set of transfer ports configured to connect to output ports of the manifold. actuation input of the cassette assembly. The first transfer port assembly comprises a first spatial arrangement configured to mate with a spatial arrangement of manifold drive output ports. The second transfer port arrangement comprises a second spatial arrangement configured to match a spatial arrangement of actuation input ports of the cassette assembly, and the first spatial arrangement of transfer ports is different from the second spatial arrangement of transfer ports. . The first spatial arrangement can cover an area of ​​the first side of the adapter housing having a first length and a first width, and the second spatial arrangement covers an area of ​​the second side of the adapter housing having a second length and a second width; and the second length may be greater than the first, so that the manifold adapter housing protrudes from one side of the manifold. The second side of the housing may include an elastomeric brush seal comprising a plurality of brush seals, each of the plurality of brush seals being associated with a transfer port on the second side of the adapter housing. The brush seal is Ln / nznz / E / Yi can be embedded under an adapter housing top plate. In another aspect, a seating apparatus for a cassette having a plug side and an opposite mounting side is disclosed. The seat apparatus comprises: a fixed frame member connected to a movable cassette holder by a plurality of links on a first side of the cassette mount and on an opposite second side of the cassette mount. The links on the first side of the cassette mount are connected to a first stationary flange of the stationary frame member, and the links on the second side of the cassette mount are connected to a second stationary flange of the stationary frame member. Each of the links may comprise a rocker arm having a first end pivotally coupled to the stationary tab and a second end coupled to an elongate slot in the cassette mount. The second end of the rocker arm is configurable to move in an arcuate path to move the cassette mount, such that the elongated slot restricts movement of the cassette mount by the rocker arm to linear movement toward or away from the member. fixed frame. The cassette mount may comprise a first movable tab and a first rail on the first side of the cassette mount, and a second movable tab and second rail on the second side of the cassette mount. Each of the movable tabs may have a surface generally parallel to the direction of movement of the cassette mount, the elongated slot being formed in the movable tab and oriented perpendicular to the direction of movement of the cassette mount, and the first and Second rails can then be configured to support the mounting side of the cassette. A handle assembly may be pivotally connected to the cassette mount such that movement of a handle of the handle assembly in a direction away from the fixed frame member moves the cassette mount away from the fixed frame member; and movement of the handle in a direction toward the fixed frame member moves the cassette mount toward the fixed frame member. The handle assembly pivot connection may comprise a first pivot connection of a first handle arm to the first stationary flange, a second pivot connection of a second handle arm to the second stationary flange, a third pivot connection of the first handle arm handle to a handle rocker arm connected to the first movable tab of the cassette mount, and a fourth pivotal connection of the second handle arm to a handle rocker arm connected to the second movable tab of the cassette mount. The first and third pivot connections and the second and fourth pivot connections may be spaced apart from each other on the first and second arms of the handle. A third stationary flange of the stationary frame member may face the handle assembly and may be generally perpendicular to the first and second stationary flanges. The handle assembly may include a spring-loaded plunger configured to fit into a hole or recess in the third stationary tab so that the cassette mount can be locked in a retracted position when the handle of the handle assembly is moved toward the limb. stationary frame. BRIEF DESCRIPTION OF THE DRAWINGS The non-limiting embodiments of the present invention will be described by way of example with reference to the accompanying figures, some of which are schematic and are not intended to be drawn to scale. In the figures, each component illustrated as the same or nearly the same is typically represented by a single numeral. For purposes of clarity, each component in each figure is not labeled, nor is each component of each embodiment of the invention shown where illustration is not necessary to enable those skilled in the art to understand the invention. Figures 1A to IB are schematic cross-sectional views of one embodiment of a pump cassette during a fill stroke and a delivery stroke; Figures 2A to 2B are schematic cross-sectional views of another embodiment of a pump cassette during a fill stroke and a delivery stroke; Figures 3A to 3B are schematic cross-sectional views of an exemplary diaphragm valve during operation; Figures 4A to 4B are schematic cross-sectional views of another embodiment of a pump cassette during operation; Figures 5A through 5B are schematic cross-sectional views of optional additional features of exemplary pump cassettes during operation; Figure 6 is a perspective view of an exemplary pump or valve cassette; Figure 7 is a front perspective view of the pump or valve cassette shown in Figure 6; Figure 8 is a perspective view of an inner side of an outer plate of the exemplary cassette shown in Figures 6 and 7; Figure 9 is a perspective view of an actuation side of an intermediate plate of the exemplary cassette shown in Figures 6, 7 and 8; Figure 10 is a close-up view of the actuating side pump and valve stations of the intermediate plate shown in Figure 9. Figure 11 is a perspective view of a fluid side of an intermediate plate of an exemplary pump or valve cassette; Figure 12 is a perspective view of another embodiment of a pump or valve cassette; Ln / nznz / E / Yi Figure 13 is a perspective view of a first side of an intermediate plate Ln / nznz / E / Yi of the exemplary cassette shown in Figure 12; Figure 14 is a perspective view of a second side of the intermediate plate shown in Figure 13; Figure 15 is a rear perspective view of a cassette assembly; Figure 16 is a front perspective view of the cassette assembly shown in Figure 15; Figures 17A to 17B represent front and rear perspective views of another embodiment of a cassette assembly; Figure 18 is an exploded view of a prior exemplary cassette assembly; Figure 19 is a side view of an assembled cassette assembly of Figure 18, showing the lines of action of the assembly and associated connectors; Figure 20 is a perspective view of another embodiment of a cassette mount secured in a frame mount; Figure 21 is an exploded view of the frame assembly shown in Figure 20; Figures 22A to 22B are front and rear perspective views of an exemplary frame assembly top plate; Figure 23 is a front perspective view of a hemodialysis apparatus. Figure 24 is a front perspective view of a housing of the hemodialysis apparatus shown in Figure 23; Figure 25 is a rear perspective view of the housing shown in Figure 24; Figures 26 through 29 are schematic representations of an exemplary pressure distribution manifold; Figure 30 is a perspective view of an upper portion of the housing of Figure 24 enclosing a cassette assembly that is disconnected from a corresponding manifold assembly; Figure 31 is a perspective view of the top of the housing as shown in Figure 30, with the cassette assembly connected to the corresponding manifold assembly; Figure 32 is a rear perspective view of an exemplary pressure distribution manifold and associated interface adapters; Figure 33 is an exploded view of the pressure distribution manifold shown in Figure 32; Figure 34 is a perspective view of the exemplary pressure distribution manifold and associated sensor board; Figure 35 is a perspective view of a lower block of the collector. Ln / nznz / E / Yi pressure distribution shown in Figure 34; Figures 36 to 37 are bottom and top perspective views of an upper block of the pressure distribution manifold shown in Figure 34; Figure 38 is a flow path schematic of an exemplary pressure distribution manifold pneumatic channel arrangement; Figure 39 is a perspective view of an exemplary pneumatic channel in the pressure distribution manifold; Figure 40 is a perspective view of the exemplary pneumatic channel arrangement shown in Figure 39 in the pressure distribution manifold; Figure 41 is a flow path schematic of an exemplary pressure distribution manifold pneumatic channel arrangement; Figure 42 is a perspective view of another exemplary pneumatic channel in the pressure distribution manifold; Figure 43 is a perspective view of the exemplary pneumatic channel arrangement shown in Figure 42 in the pressure distribution manifold; Figure 44 is a rear perspective view of a hemodialysis device housing, showing the location of the pressure distribution manifold; Figure 45 is a front perspective view of the hemodialysis device housing, showing the installation of exemplary manifold adapters. Figure 46 is a left front perspective view of the exemplary cassette assembly positioned in a housing top and aligned with manifold adapters. Figure 47 is a perspective view of the exemplary pneumatic distribution manifold, positioned below the housing cutouts for the manifold adapters; Figure 48 is a rear perspective view of the hemodialysis device housing, showing installation of the exemplary pressure distribution device and interface adapters; Figure 49 is a front perspective view of the hemodialysis device housing, showing installation of exemplary interface adapters; Figure 50 is a partial sectional view of the housing of the hemodialysis device, showing an exemplary cassette loading assembly mounted to the roof of the housing; Figure 51 is a perspective view of an exemplary manifold adapter rail; Figure 52 is a partially exploded top perspective view of an exemplary manifold adapter positioned on the pressure distribution manifold; Ln / nznz / E / Yi Figure 53 shows the partially exploded view of the manifold adapter of Figure 52, seen from a bottom perspective; Figure 54 is a plan view of an exemplary brush seal of a commutator adapter; Figure 55 is a cross-sectional view of a section of the brush seal of Figure 54; Figure 56 is a bottom perspective view of the exemplary cassette loading assembly when the operating handle is in a raised (disengaged) configuration; Figure 57 is a front perspective view of the exemplary cassette loading assembly when the operating handle is in a lowered (engaged) configuration; Figure 58 is a bottom perspective view of the exemplary cassette loading assembly of Figure 57 with the operating handle in a lowered configuration; Figure 59 is a rear perspective view of the exemplary cassette loading assembly of Figures 57 and 58 with the operating handle in a lowered configuration; Figure 60 is a schematic representation of a fluid flow path in the hemodialysis device; Figures 61 and 62 are graphical representations of the pressure variation in an actuation chamber of a pump in the hemodialysis device; Figure 63 is an exemplary flowchart of an algorithm for controlling pressure in an actuating chamber of a pneumatically driven pump. Figure 64 is an exemplary flowchart for an alternative pressure control algorithm for a pneumatically driven pump; Figure 65 is an exemplary flowchart for an end of stroke detection algorithm for an exemplary air-powered pump; Figure 66 is an exemplary flowchart for an occlusion detection algorithm for fluid pathways in a diaphragm-based pumping system; Figure 67 is an exemplary flowchart of an algorithm for determining resistance to flow during a pump-fill stroke; Figure 68 is a schematic representation of fluid flow paths in an exemplary hemodialysis system; Figure 69 is a schematic representation of an isolated sectional view of the fluid flow paths of the hemodialysis system shown in Figure 68; Fig. 70 is a state diagram showing a disinfection procedure for the hemodialysis system; and Ln / nznz / E / Yi Figure 71 is a state diagram representing temperature control before and during a disinfection procedure. DETAILED DESCRIPTION OF THE INVENTION Cassettes with fluid channels and flat tires In some pumping applications, it is advantageous to place the actuation ports of a fluid or pneumatically actuated valve or pump cassette on the edge, thin or narrow side of the cassette, rather than on the wide side of the cassette. This allows the cassette to be plugged on the thin side rather than the wide side into a receptacle comprising a series of actuation ports associated with a pressure supply manifold. This can allow one to maximize the functions that a pump / valve cassette can perform within a confined space. In some circumstances, general space limitations may also make it advantageous to minimize the overall thickness of the cassette. This can be achieved by making the cassette only minimally thicker than the excursion range of the closed diaphragms. Ideally, each cassette outer plate functions primarily as the roof or end wall of any pump or valve actuation or liquid transport chamber or channel, with insufficient thickness to completely enclose any liquid or actuation channels to run generally parallel to the face or wide side of the cassette. The actuation channels are configured to run in a gap between an intermediate plate and an outer plate (eg, the first outer plate) of the cassette, within an interplate gap that defines the maximum range of excursion of one or more diaphragms of the cassette. cassette. The width of the gap between plates (and consequently the maximum range of excursion of a flexible membrane or diaphragm) can be predetermined by the height of the channel walls formed on the actuating and / or liquid-carrying side of the intermediate plate. of the cassette. The height of the channel walls on one side of an intermediate plate may be different from the height of the channel walls on the opposite side of the intermediate plate. For example, to accommodate a desired fluid flow rate, the walls of the channels on a liquid side of the intermediate plate can be taller to provide a larger cross-sectional area of ​​the liquid transport channels, while the requirements The cross section (and therefore the height of the channel wall) of the actuation channels on the actuation side of the intermediate plate can be less. Figures 1A and IB schematically illustrate a cassette 10 in cross section near the end of a fill stroke and near the end of a delivery stroke, respectively. An intermediate plate 12 is positioned between a first outer plate 14 and a second outer plate 16. A flexible diaphragm 18 is positioned in the first space between Ln / nznz / E / Yi plates 20, and liquid flow channels are present in the second gap between plates 22. To reduce the thickness of a pump and / or valve cassette, any actuation channel preferably runs in the first space between plates 20, a space defined by the depth of excursion, depth of travel, or linear interval E that a diaphragm travels between the intermediate plate 12 and the first outer plate 14. In the case of an onboard diaphragm pump, its volume of stroke is a function of the depth of excursion E of your diaphragm 18 and the effective surface area the diaphragm occupies on the wide side of the cassette. The preferred depth of excursion E of a diaphragm may also depend on how effectively the stroke volume of the diaphragm can be increased by increasing its effective surface area. In this embodiment, two pump chamber liquid ports 24a, 24b are shown, representing an inlet and an outlet, each connected to separate fluid channels within the interplate space 22, the fluid channels schematically separated by the wall 38. (The direction of liquid flow shown is arbitrary and depends on which liquid line is opened or closed by a downstream valve during a diaphragm fill stroke or delivery stroke.) In another embodiment, as shown in Figures 2A and 2B, a single pump chamber liquid port 24c (or two or more of these ports) may be used, which then alternates between being an inlet port and an inlet port. outlet depending on which downstream valves are open or closed in the single liquid line in plate gap 22. When the volume of the actuation chamber 26 is at a minimum, the corresponding pump chamber 28 is at its maximum (fill stroke, see figures ΙΑ, 2A). When the volume of the actuation chamber 26 is at its maximum, the volume of the corresponding pump chamber 28 is at its minimum (delivery stroke, see Figures IB, 2B). Once the depth of excursion E of the diaphragms in the cassette has been chosen, the thickness of the cassette T can be reduced by avoiding locating the actuation ports directly over the diaphragms being actuated (as in prior art designs). . This is accomplished by placing the actuation ports on the thin or narrow side of the cassette and passing the actuation channels to their respective diaphragms in the first interplate space 20 in the cassette 10. This space is bounded by the intermediate plate 12 on the on which the diaphragm 18 sits and the first outer plate 14 which provides a cover or roof for the actuation chamber 26 for each diaphragm 18. Surrounding the perimeter of each diaphragm is a wall 30 spanning the space between plates 20 which, together with The outer plate 14 completes each actuation chamber 26, except for an actuation port or window 32 that connects the actuation chamber 26 to its corresponding actuation channel (represented by the arrow in the first space 20 between plates). The actuation channel then runs in the interplate space 20 to a peripheral edge or narrow side of the cassette, terminating there as a cassette actuation port (see, for example, Figure 9). Note that the actuation channel may be less than the depth Ln / nznz / E / Yi provided by the gap 20 between plates, depending on the depth of excursion E that has been specified for the diaphragm 18. To minimize the total thickness T of the cassette 10 for a given specified diaphragm excursion depth E , the nominal thickness P of each plate 12, 14, 16 can be minimized (within the constraints of structural rigidity and any constraints imposed to achieve a weld or cement of the outer plate to the channel walls of the intermediate plate). Depending on the fluid flow requirements, the thickness of the cassette can also be minimized by reducing the depths of the liquid flow channels (ie, the height of the channel walls) within the second space 22 between plates. The total thickness T of the cassette may depend on the amount of depth required by the liquid flow paths or channels on an opposite side of the middle plate 12 of the cassette 10 into the second space 22 between plates. In the pump shown in Figures 1A to IB and the valve shown in Figures 3A, 3B, the required depth of the liquid channel determines the depth of the second space 22 between plates. Depending on the liquid flow rates specified for the cassette, the second interplate space 22 may have a depth L substantially less than the depth E of the first interplate space 20 . As shown in Figures 3A, 3B, for any given diaphragm valve station, there are at least two liquid channels: a first channel terminating at valve port 34a of intermediate plate 12, and a second channel terminating at valve port 34a of intermediate plate 12. into valve port 34b of intermediate plate 12. (In some embodiments, a plurality of liquid channels could terminate in separate valve ports in the intermediate plate of a single valve station). As shown in Figures 3A and 3B, the depth of excursion E is determined in the case of a diaphragm valve by the degree of relaxation required to allow the diaphragm 18 to lift out of the fluid ports 34a,b which is designed to occlude. The valve diaphragm 36 can be moved away from ports 34a,b under negative actuation pressure to allow fluid flow as shown in Figure 3A, or it can be moved to occlude ports 34a,b under positive actuation pressure to interrupt the flow. liquid flow as shown in Figure 2B. The separate liquid channels in the valve station of a cassette are schematically represented by the wall 38 shown in the second space 12 between plates. In the illustration shown, the valve ports 34a,b may optionally comprise raised elements 40 (placed circumferentially around the valve port) to improve the sealing efficiency of the diaphragm. Such a raised element need only be present around one of the valve ports to be effective. Therefore, as the valve diaphragm relaxes or moves away from the valve fluid ports, fluid is allowed to flow from a fluid channel, through its associated port to a valve chamber. liquid, and then through the liquid port of a second liquid channel connected to that valve station. The Ln / nznz / E / Yi The choice of the cross-sectional area of ​​the liquid channels may depend on a desired resistance to liquid flow and a desired retention volume or dead space occupied by the liquid channels in the cassette. The desired cross-sectional area of ​​the liquid channels will in turn determine the depth of the liquid channel (or the height of the channel wall) that occupies the second interplate space 22 between the intermediate plate 12 of the cassette and the second plate. 16 outer. The fluid and actuation channels may be formed from the intermediate plate or the respective outer plates, or they may be formed independently of the outer plates or the intermediate plate. In a preferred arrangement, the intermediate plate is formed in a mold, 3D printed or otherwise cast with desired channel walls on both sides of the intermediate plate, so that the construction of the outer plates can be simplified. The outer plate 14 can comprise the ceiling or the limiting wall of the diaphragm of the actuation chamber 26, and the outer plate 16 can comprise the ceiling or the liquid channels in the cassette. In this way, the inter-plate gap between the intermediate plate and the outer plates can be further reduced. As shown in Figure 1A, in a preferred embodiment, the thickness T of a pump or valve cassette 10 may be defined by the nominal thicknesses P of each of the intermediate plates and the two outer plates, plus the depth of excursion E of the diaphragm and the depth L of the liquid channels defined by the second space 22 between plates provided in the cassette. To maximize the efficiency of positioning and distributing valves and pump stations on the intermediate plate 12, it may be advantageous to place some actuation channels and actuation chambers on both opposite sides of a single intermediate plate 12. In this case, the thickness T of a cassette will be determined by the depth of excursion of the largest diaphragm on either side of the intermediate plate. For example, if the depths of excursion E of the pump diaphragms are the same on each side of the intermediate plate 12, then the thickness T of the cassette will equal (2xE) + (3xP). Figures 4A and 4B show an alternative embodiment of a diaphragm pump of a pump cassette 50. In this case, the fluid ports of the pump chamber have been replaced by a wide opening 42 through which the diaphragm 44 can pass as it moves from a fill position (FIG. 4A) to a discharge position. supply (figure 4B). The total thickness T' of this cassette is therefore determined from the total excursion distance or length E' of the diaphragm 44, plus the thickness P of the two outer plates 46, 48. The pump diaphragm 44 takes advantage of practically all the thickness of the cassette 50 to substantially increase the stroke volume of the pump. In this case, the pumping chamber 52 is defined by the liquid side of the diaphragm 44 and a circumferential sealing wall 54 topped by the second outer plate 48. The liquid inlet / outlet pump ports 56, 58 are shown in this embodiment, although other embodiments may include only a single port that acts as both inlet and outlet, or may include a plurality of ports whose inlet or outlet function is determined. by downstream valves in the liquid channels associated with each port of the pump. In this arrangement, the overall thickness of a cassette can be minimized, because the stroke volume generated by the diaphragm is essentially doubled in the absence of the intermediate plate. For any desired pump stroke volume, the distances between plates can be reduced substantially. Figures 5A and 5B show additional features that can be optionally included in a pump or valve cassette. In this case, the diaphragms 60, 62 are shown to be secured against the intermediate plate 12 by means of a diaphragm retainer or retaining wall 68 (see also retainer 100 in Figure 8). In other embodiments, the perimeter bead 64, 66 respectively of the diaphragms 60, 62 can be attached to the intermediate plate 12 by means of an adhesive, by heat welding, by having a section of the intermediate plate overmolded to surround and hold the bead, applying a solid continuous ring in position against the heel of the diaphragm, or by a number of other methods which ensure that the diaphragm is secured to the intermediate plate and that a seal is formed between the heel of the diaphragm and the intermediate plate to separate the chamber from actuation chamber 26. In the example shown, a retainer or retaining wall 68, 100 is installed within the perimeter wall 30 of the actuation chamber 26. Shown in cross section, the illustrated portion of the wall dam 68 shows two fenestrations, slots, windows, or holes 70 that allow actuation pressure (eg, pneumatic pressure) to be transmitted to the actuation side of the diaphragm 60. For most of its circumference, the retainer or retaining wall 68 extends uninterrupted from the inner side of the first outer plate 14 or 46 to a position adjacent the heel 64, 66 of the diaphragm 60, 62. If the heel Made of elastomeric material, the retainer or retaining wall 68, 100 acts to partially compress the bead during cassette mounting when the first outer plate is installed against the opposite intermediate plate. A tight fit helps ensure the diaphragm is securely installed and an air / water tight seal has been formed. In a preferred arrangement, two or even a plurality of retaining wall fenestrations 70 (or holes) may be distributed around the circumference of retaining wall 68, so that positive or negative actuating pressure can be transmitted to a plurality of diaphragm sections 60, 62 relatively simultaneously. In some cases, it may be advantageous to ensure that there is a continuous rigid clamping structure against the entire circumference of the heel or rim of the diaphragm. In that case, a plurality of holes in the retaining wall 68, 100 may be preferable to one slot. Ln / nznz / E / Yi Ln / nznz / E / Yi extending to the heel of the diaphragm. Alternatively, a continuous rigid ring (eg, metal or plastic washer) (not shown) applied against the heel of the diaphragm can be combined with a slotted retaining wall 68, 100 to achieve the same result. Preferably, the outer edge of the ring or washer bears on the inner side of the valve or pump station perimeter wall and compresses only the heel portion of the diaphragm, and the inner edge of the ring or washer prevents contact with the diaphragm. as it experiences transitions from the heel of the diaphragm to the body of the diaphragm. In the example shown, the diameter of the retainer or retaining wall 68, 100 is small enough to allow a space 72 to exist between it and the perimeter wall 30 of the actuation chamber 26. The space 72 allows the distribution of the hydraulic or pneumatic actuating pressure to the individual fenestrations 70 of the retaining wall 68. The retainer or retaining wall 68, 100 may be a separate item that assembles with the other components of the cassette, or it may be formed or co-molded with the intermediate plate 12 or the first outer plate 14 of the cassette. Figures 5A and 5B also illustrate that the inner wall of the actuation or first outer plate 14 or 46 may optionally comprise a curved buttress 74 or 76 that helps to conform the inner wall of the actuation chamber 26 to the curvature of the diaphragm 60. , 62 as it extends completely towards the first plate 14 or 46 on the actuation side. This can help reduce stress on the more peripheral portions of the diaphragm 60, 62 when it is fully retracted into the actuation chamber 26. Similarly, as shown in Figure 5B, a curved buttress 78 can be placed along the the end wall (liquid or second outer plate 48) of the liquid pumping chamber 52 for a similar reason. In these examples, shaping the interior wall of outer plates 14, 46, and 48 does not require increasing the overall thickness of cassette 10 or 50. Buttresses 74, 76, 78 may be separate inserts attached to the respective outer plates. , or they can be formed and co-molded with the outer plates such that any additional thickness of the outer plate is caused to encroach into the inter-plate space rather than extend beyond the outer surface of the outer plate. The outer plates can be molded to curve inwardly from the outside of the plate toward the actuation chamber or fluid chamber, without increasing the overall thickness of the cassette. Figure 6 shows a rear perspective view of an exemplary cassette 80 including a plurality of valve stations 82 and an exemplary pump station 84. In one example, a cassette was constructed to have a length of approximately 16 cm, a width of approximately 19 cm, and a thickness of approximately 1.5 cm. The first outer plate or actuation plate 86 has been molded with notches on its outer surface at the valve 82 and pump 84 stations to provide a curved inner surface for Ln / nznz / E / Yi adapt to the associated diaphragms in those regions. In this example, the nominal thickness of each of the first outer plate 86, the second outer or liquid side plate 88, and the intermediate plate 90 is approximately 2 mm, while the total thickness of the cassette is approximately 15 mm. The first 92 and second 94 interplate spaces are each approximately 4.5 mm wide. In this example, the pump diaphragm has a range of excursion approximately equal to the first gap 92 between 4.5mm wide plates. The cassette actuation channel ports 96 are shown arranged within the first interplate space 92 of the cassette 80. Thus, a diaphragm excursion of approximately 4.5 mm can be achieved in a cassette whose width is approximately 10.5 mm plus the width desired for the liquid channels in the second plate gap 94. In this case, the second plate gap 94 has the same width as the first plate gap 92, but in other embodiments it could be less (depending on the flow characteristics). desired for liquid channels). In this example, the excursion range of a cassette diaphragm is approximately 30% of the full width of the cassette. Figure 7 shows a front perspective view of the cassette of Figure 6, revealing the cassette fluid channel ports 98 disposed within the second interplate space 94 of the cassette 80. Figure 8 shows a perspective view of the inner side of the first outer plate 86 of the cassette 80. In this example, the diaphragm retainer or retaining walls 100, 102 have been molded as an integral part of the inner side of the first plate. outer 86. (In dual-function cassettes, both sides of the intermediate plate can be pump or valve actuating sides, so that both the first and second outer plates can include retainers or retaining walls 100, 102 ). In this example, each diaphragm retainer 100, 102 has a series of fenestrations or holes 104 and, optionally, a slot 106 on the top side to distribute actuating pressure evenly over the diaphragm to be retained against midplate 90. The interior walls The curved sections 108 of the outer plate 86 at the valve and pump stations are arranged to conform to the associated diaphragm shape as it extends fully into the actuation chamber (within which retainers 102 are positioned). In some cases, optionally, ribs 109 may be included in the mold of the outer plate 86, which are configured to invade the mating actuation channels of the opposite intermediate plate. The ribs 109 can be constructed to have a cross-sectional size and length to adjust the total volume of the associated actuation channel to a predetermined volume. (This can help to minimize the amount of pneumatic gas volume to be delivered (or compressed) and can improve the responsiveness of diaphragms associated with actuating a pressure supply manifold. The actuation volume adjustment ribs can be particularly Ln / nznz / E / Yi are advantageous in an arrangement where both sides of the intermediate plate carry actuation and / or fluid channels, or where the space between plates must accommodate a larger diaphragm excursion range. In that case, the installation of performance volume adjustment ribs reduces the transmission volume of the performance channels and can improve the performance of a cassette. In addition, when synchronous valve actuation is desired, it may be advantageous to match the transmission volume of the actuation channel between valve assemblies having variable distances from the cassette actuation ports. Properly sized volume adjusting ribs can be used to adjust cassette valve operations in this manner. Figure 9 shows a perspective view of the actuation side of the intermediate plate 90 of the cassette 80. In this example, the actuation channels 110, the pump station perimeter walls 112, and the valve and actuation ports 96 of the cassette have been formed or molded as part of the intermediate plate 90. In this example, most diaphragm valve or pump stations are powered by a separate actuation channel 110 leading from a dedicated cassette actuation port 96. The fluidic or actuation channels of the cassette may be individually formed conduits, or each channel may comprise two interplate-spanning walls fused and spanning between the middle plate and the first outer plate or second outer plate. In some cases, it may be desirable to actuate two or more valve stations at the same time, in which case a single path 114 of the actuation channel may feed the two or more valve stations, as shown with valve stations 116, 118 Each valve station is surrounded by a perimeter wall 112 that seals the station when the first adjacent outer plate 86 is welded to the intermediate plate 90. Cassette plates can be formed (eg, injection molded) from moldable plastic material, such as polysulfone, which cures to a hard or rigid consistency. Other plastics or materials such as metal can also be used. Other molding methods, as well as newer techniques such as 3D printing, can be used to form the middle plate and outer plates. The outer plates can be fused to the intermediate plate using adhesives or localized heating by ultrasonic or mechanical vibration. In a preferred method, the outer plates may be transparent, translucent, or may allow transmission of laser wavelengths to allow laser welding of the outer plates to an opaque intermediate plate. The weld seals the valve and pump regions of the outer plate to the perimeter walls and channels of the respective valve and pump stations of the intermediate plate. Each perimeter wall 112 forms part of the actuation chamber of the respective Ln / nznz / E / Yi valve or pump station, and each communicates with an actuation channel 110 through an actuation chamber port 120 in the perimeter wall 112. The pump station 84 in this example has two pumping ports 24a, 24b connecting the liquid channel on the opposite (second) side of the intermediate plate with the first side of the intermediate plate shown in the drawing. One of them can function as the entrance to the pump room, while the other functions as the exit to the pump room. In other embodiments, the pump region may have a single pump port or a plurality of pump ports. The valve stations in this example each have two ports connecting two separate liquid channels on the second side of the intermediate plate to the valve station on the first side of the intermediate plate shown. Also, in this example, one of the valve ports 34a has a raised perimeter lip 40 to improve the sealing of the valve diaphragm against the valve port when positive pressure is applied to the diaphragm. Figure 10 shows a close-up view of the middle plate 90 of Figure 9. In this case, a pump diaphragm 122 and a valve diaphragm 124 are shown to be installed in their respective pump and valve stations. The diaphragms are held in place and sealed against the intermediate plate 90 by the corresponding retaining walls or retainers 100, 102 shown in Figure 8. Note that the retaining walls or retainers 100, 102 fit (loosely) inside the circumference of the perimeter or the walls of the chamber 112 of the respective valve or pump stations. The difference in diameter of the perimeter wall and the retaining wall is sufficient to allow a gap 72 (see Figure 5A) to exist between the two so that actuating fluid or gas pressure can be distributed evenly around the associated diaphragm. Figure 11 shows the second side of the intermediate plate 90 of the cassette 80. In this example, the liquid channels 126 have been molded as part of the intermediate plate 90. In the case of a pump station 84, each of the The two ports 24a, 24b are associated with a separate liquid channel 128, 130, such that one port functions as a pump chamber inlet port, while the other port functions as a pump chamber outlet port. the bomb. Whether a particular port functions as an inlet or outlet can be determined by the downstream valve being actuated or closed. Figure 12 shows a variation of a cassette 132 that includes additional optional features (which can be individually included or excluded in any cassette design). In this case, the cassette incorporates actuation ports, actuation channels, and actuation chambers on both sides of a center plate 134. The first interplate space 136 and the second interplate space 138 each include actuation and liquid channels, as well as actuation cassette and fluid ports. In this view, two rows of actuation ports 140, 142 are Ln / nznz / E / Yi visible on a narrow edge or side of the cassette, allowing that edge of the cassette to be connected to a connector or interface that communicates with a pressure distribution manifold. In this mode, the total thickness T2 of the cassette, which includes the thickness of each of the center plate 134, the first outer plate 144, and the second outer plate 146, plus the width of the first 136 and second 138 gaps between plates, allows pumping or valve diaphragms to seat on the first or second side of the intermediate plate, or both. This potentially increases the number of valve or pump stations that can populate a cassette having a given wide side dimension. In this embodiment, the total thickness T2 of the cassette can be minimized while maximizing the density of the pump or valve stations that can be included in the cassette 132, with the excursion intervals of the closed diaphragms comprising a substantial majority of the thickness. full cassette. For example, in a cassette with a 'dual function' intermediate plate (allowing actuation channels and chambers on either side of the intermediate plate), nominal plate thicknesses of 2mm, along with plate gaps of 5mm each to accommodate diaphragm deviations of 5mm, results in a total cassette thickness of 16mm, nearly 2 / 3 of which comprises desired diaphragm deviation intervals. Figures 12 and 13 show a dual function cassette intermediate plate 150 in which the first 152 and second 154 sides of the intermediate plate each include liquid handling and actuation channels, incorporating actuation ports, actuation channels , actuation chambers and liquid channels on each side of the intermediate plate. A plurality of valve stations 156 are shown in this example, although on-board pumping stations may also be included in other embodiments. In this respect, the cassette is similar to cassette 132 of Figure 12. Optionally, this intermediate plate 150 is further designed for use in a cassette assembly incorporating external pump capsules or liquid mixing capsules whose volume requirements preclude their inclusion as on-board pump or mixing chamber stations in a single cassette. When larger volumes of liquid run are needed, two or more cassettes can be arranged so that the liquid or actuation lines can be connected to extension conduits 158, 160 perpendicular to the face of the cassette which can be connected to capsules. external located between two cassettes. The passages originate from the intermediate plate of the cassette (eg, formed or molded with the intermediate plate) and penetrate the first or second outer plate to provide a direct connection to an external self-contained diaphragm pump, self-contained mix chamber, or autonomous balance chamber. If the conduits are rigid, they can also serve as structural elements that help hold the cassette assembly together. The perpendicular conduits may also be used as fluid ports for connection to a fluid source or destination external to the cassette. In this case, the termination of the conduit can be constructed to make a connection with flexible or malleable tubing. In this type of cassette, the cassette actuation ports and the initial portions of the actuation channels may still be located in the interplate space of the cassette, until they reach the point where the fluid or actuation line must exit. of the cassette to connect to an associated capsule pump, balance chamber capsule, or mixing chamber. With this configuration, the cassette mount is a substantial improvement over the previously described cassette mounts due to the more efficient arrangement of cassette actuation ports. Since the actuation ports are all located along one edge of the cassette, the cassette can be plugged directly into an associated pressure supply manifold or rigid receptacle arrangement without the need for separate hose connections and connectors. . The cassette center plate 150 of Figures 12 and 13 also shows that the actuation channels and liquid channels can be routed from one side to the second opposite side of the intermediate plate to increase the number of valve or pump stations that can be routed. incorporate into a cassette of a particular size. Routing of a fluid or actuation channel can be hampered by the presence of other channels, pump stations, or valve stations that prevent a direct path from a cassette port to the destination valve or pump station. In that case, redirecting the actuation or liquid channel to the first / second side of the intermediate plate may allow the channel to bypass an obstructing structure on the second / first side of the intermediate plate. The bypass can simply make a single penetration of the intermediate plate to the opposite side, or it can penetrate the intermediate plate to avoid an obstructing structure and then return to the initial side of the intermediate plate to reach its pump station destination or valve. Figure 14 shows the second side 154 of the intermediate plate 150 of the cassette. An actuation port 162 arranged to feed valve station 164 lacks an uninterrupted path to the valve station due to the presence of an extension conduit 168. Actuation channel 170a connected to cassette actuation port 162 terminates in a port 172 of the actuation channel penetrating the intermediate plate 150. As shown in Fig. 13, the actuation channel 170b on the first side 152 of the intermediate plate 150 can connect the actuation channel 170a with the actuation channel 170c through actuation channel port 174, to complete the actuation channel path from cassette actuation port 162 to valve station 164. Whether a cassette includes channels and actuation chambers, as well as fluid channels, on both sides of the intermediate plate (i.e., a dual-function intermediate plate), a cassette can be arranged to have fluid cassette ports located at one narrow side or edge of the cassette, so that a plurality or bank of such cassettes can be stacked to Ln / nznz / E / Yi Ln / nznz / E / Yi form a compact cassette group. Figure 15 is a rear perspective view of a cassette group 176 comprising a plurality of individual cassettes 178a-d stacked from broad side to broad side. Each cassette 178a-d has one or more cassette trigger ports 180 located on the narrow side of the cassette in the first interplate space 182a-d, with the trigger ports oriented in the same direction as the individual cassettes in the group. of cassettes can be plugged into their respective corresponding connectors or receptacle ports of a receptacle assembly, the connectors or receptacle ports being positioned side by side and connected to, mounted on or attached to a pressure distribution manifold. The cassettes of a group of cassettes can be arranged to be in contact with each other, whether or not they are fused or adhered to each other. Alternatively, they may be placed side by side loosely or with some gap, so that each cassette in a group can be individually inserted or withdrawn from its corresponding receptacle assembly without disturbing neighboring cassettes. This allows individual cassettes to be placed on rails or tracks so that their actuation ports can align correctly with their respective connectors or receptacles, and so that they can be inserted and removed more easily. Cassette receptacle mounts can be located side by side to provide a spatially compact cassette pool. Optionally, the cassette receptacle mounts can be located within a single housing, which can provide alignment and insert / remove tracks for the individual cassettes. Or each cassette receptacle assembly can be included in a separate housing for the same purpose. In the context of providing individualized fluid circulation to a number of objects, the arrangement allows a single cassette to be exchanged for a cassette having different characteristics (with respect to the number and distribution of pump and valve stations, and liquid flow paths). ). Thus, as the fluid flow requirements for any individual object change, the cassette group configuration allows for quick and convenient adaptation of a cassette to the needs of its associated object. Furthermore, neighboring cassettes in a group of cassettes can be interconnected through their respective liquid ports by, for example, jumper lines. In this way, complex liquid mixing procedures can be carried out when it is necessary to provide an object with solutions with particular constituents at particular concentrations. Thus, one or more cassettes in a group of cassettes can be dedicated to a single object if desired. Figure 16 is a front perspective view of the cassette group 176 of Figure 15. In this example, for convenience of illustration, the cassette fluid ports 184 are located on a narrow side of each cassette 178a-d opposite the other. of the 180 ports of action. Although the actuation ports are preferably arranged on the same corresponding edges of the cassettes (so that a pressure supply manifold can be placed Ln / nznz / E / Yi behind the cassette group), the fluid ports of the individual cassettes do not need to be positioned along the same edges of the cassettes. In this embodiment, the cassette fluid ports 184 are positioned within the second interplate spaces 186a-d of the respective cassettes 178a-d. Thus, the cassette group 176 can be oriented to face outward from one or more receptacle assemblies (not shown) connected to, mounted on, or attached to a pressure distribution manifold. Each cassette 178a-d is capable of providing fluid circulation to a separate object, such that the number of individual cassettes in a group can match an equal number of objects requiring fluid circulation. For example, a plurality of stations of biological cells, tissues, or organs arranged for growth, experimentation, or testing may be supplied with circulating fluids, drugs, nutrients, or other chemicals by a plurality of cassettes in a cassette group, each potential cassette mind by providing each cell station, tissue station, or organ station with liquid solutions having similar or different compositions. A group of cassettes such as cassette group 176 can also be configured to serve as a solution mixing station, with the liquid outlet from one cassette in the group providing the liquid inlet from a neighboring cassette in the group, thus allows for complex solution mixing protocols. As such, two or more cassettes can be reconfigured to serve a single object. Figure 17A shows a rear perspective view, and Figure 17B shows a front perspective view of a cassette group 186 incorporating dual function intermediate plate cassettes 188a-d. In other embodiments, a cassette group may incorporate one, two, or more dual-function intermediate plate cassettes among one or more single-function intermediate plate cassettes. In this case, representative actuation ports 190 of the second plate gap 182a-d and representative first plate gap liquid ports 192a-d 186a-d are shown. Depending on the number and size of the individual pump and valve stations in the 188a-d cassettes, the use of dual-function intermediate plate cassettes may allow for the placement of a higher density of multi-purpose pump and valve stations in a relatively small footprint. reduced. In some applications, the stroke volume or liquid chamber volume of a pump or other type of chamber exceeds the volume that an onboard pump or chamber can accommodate. In this case, external pumps or chamber pods have been used and placed between two cassettes. Liquid lines and / or actuation lines arise from opposite faces of the two cassettes to supply the outer chambers or pumps, allowing liquid to flow, for example, from a first cassette to the outer capsule and then to the second cassette, each cassette houses an upstream or downstream valve station to control the flow of liquid. Or one Ln / nznz / E / Yi outer pump actuation line may arise from the face of a first cassette, while the liquid inlet and outlet line may arise from the opposite second cassette. This type of cassette mounting also allowed liquid lines to be connected directly from the face of one cassette to the face of an opposing cassette. In earlier implementations, as shown in Figure 18, the faces of the opposing cassettes 194,196, 198 also included actuation ports 200 for the onboard pump stations and actuation ports 202 for the valve stations, along with liquid ports. 204 and fluid 206 and actuation lines 208 to the external pumps 210 or chambers 212. This arrangement led to a large number of flexible tubing connections for actuation and fluid lines attached to the inside faces of the cassettes, which raised challenges for manufacturing, assembly and maintenance. Figure 19 shows an earlier cassette assembly in which pneumatic actuation lines 214 ran from actuation ports 216 on the cassette faces 218 to block-style connectors 220a,b for rear connection to a distribution manifold. pressure used to operate the cassette assembly. This was in addition to the fluid lines 222 running from the fluid ports 224 on the individual cassettes. This type of cassette mounting has been substantially improved by incorporating the cassette designs of the present disclosure. Dialysis cassette set Figure 20 shows an example of a cassette assembly 226 that performs substantially similar liquid processing functions as the earlier cassette assembly of Figures 17A-17B and 18, and serves to illustrate how the cassettes of the present disclosure improve substantially the construction, assembly and maintenance of said cassette assembly. In this example, the cassette assembly 226 shown is used to mix, process, and move dialysate solution in a portable hemodialysis machine. But the uses for this type of cassette or cassette mount (i.e., cassettes having rim-mounted actuation ports with actuation channels extending between the plates and parallel to the face of the cassette) are by no means limited. to hemodialysis systems. As shown in Figure 20, three cassettes 228, 230, 232 are linked by fluid handling capsules 234, 236. These inter-cassette capsules may include self-contained diaphragm pumps having drive and fluid passages, or other chambers 236 for liquid transport, which only have fluid conduits. Examples of other types of liquid-carrying capsules include fluid mixing chambers or fluid balance capsules in which flow through a first liquid line is balanced by flow through a second liquid line through a capsule having a first variable volume separated from a second variable volume by a flexible diaphragm. Each fluid handling capsule 234, 236 is fluidly connected to one or both of the cassettes flanking it, either by flexible or rigid conduits. Rigid liquid conduits 238 may be preferred, because they can Ln / nznz / E / Yi provide structural support for cassette mounting. In the case of a diaphragm pump capsule 234, both the drive and actuation conduits may extend into one or both of the flanking cassettes. Conduits 238 penetrate the face of the flanking cassette to reach a fluid or actuation channel located in the first or second interplate gap of that cassette. Generally, the actuation channels that drive the pump capsules between cassettes will be directed without interruption from a cassette actuation port to the actuation chamber of the pump capsule. The fluid channels of an inter-cassette pump capsule or other type of fluid handling capsule will connect to a corresponding inter-plate fluid channel in one or both side cassettes through one or more diaphragm valves located in the cassette. The actuation channels for these diaphragm valves, the actuation channels for the pump capsules, and any other actuation channels in the cassettes travel within the first or second interplate gap of each cassette to a first edge of the respective cassette to terminate into an actuation port of cassette 240. In the cassette assembly, each cassette 228, 230, 232 has actuation ports 240 located on one side or narrow edge of the respective cassettes, and are all configured to face the same direction, such that the actuation ports of the cassette mount occupy one side of the cassette mount. This allows the cassette mount 226 to be connected to or disconnected from one or more receptacle mounts in a single movement. With this arrangement, the need for a flexible tube to connect the actuation ports of the cassette to the corresponding output ports of the manifold is eliminated. In the example shown in Figure 20, cassette 228 is optionally configured as a single-service mezzanine cassette (in which all actuation ports are located in either the first inter-gap or the second inter-gap). . In the same example, cassettes 230 and 232 are optionally configured as dual-function mezzanine-plate cassettes, with some actuation ports located in both inter-plate spaces on either side of cassette mezzanine plates 242, 244. Of course, they are Other arrangements are possible, depending on the fluid handling tasks required of a similarly arranged cassette assembly. Figure 21 depicts a partially exploded view of the example cassette assembly 226 shown in Figure 20. The assembled cassettes 228, 230 and 232 together with intervening pumps 234 or other liquid-carrying chambers 236 are held in a frame assembly, to ensure proper alignment of the cassette ports during installation and operation. The previously described cassette assemblies could rely on rigid conduits (for example, the 238 conduit) and some retaining bars or springs to hold the assembly together (see figure 18), but did not require precisely aligned actuation ports to connect them. directly to a manifold mount. In the currently described cassette mounting, support frames 505 and / or 507 can eliminate this problem by ensuring Ln / nznz / E / Yi compactly forming the 226 cassette mount and retaining it in the required configuration or alignment. The exemplary embodiments in Figures 20 and 21 show a first carrier frame 505 and a second carrier frame 507 that can engage cassette assembly 226 from opposite directions. Some embodiments may provide similar carrier frames to secure the cassette mount 226 from adjacent sides. Other embodiments can also provide a monolithic carrier frame to secure the cassette from more than one pair of opposing sides. Carrier frames 505 and 507 may further include plate rails that can be slid onto the corresponding cassette plates of cassettes 228, 230, and 232 to mate with cassette mount 226. Connect frame components together and secure carrier plates. cassette included in the rails can eliminate the need to punch or drill holes in any of the three cassette plates to secure them to the frames. The configuration of the rails and the absence of screws, nuts or clips through the cassette plates can reduce the possibility of damaging the cassette mounting and interfering with any of the pneumatic connections or pathways of the cassette. For example, the first carrier plate 505 can include a first plate rail assembly 505A, 505B and 505C and the second carrier plate 507 can include a second plate rail assembly 507A, 507B and 507C. Plate rails 505A, 505B, 505C, 507A, 507B, and 507C may comprise elongated slots capable of partially or completely receiving at least one edge or a portion of the edge of the corresponding cassette plates of cassettes 228, 230, and 232. For For example, with reference to the first carrier frame 505, plate rails 505A, 505B, and 505C may receive cassette plate edges of cassettes 228, 230, and 232, respectively. In one embodiment, the lanes may include plugging features. For example, rails 505A and 505C of first frame 505 may include plugging features 505F and 505G positioned at the ends of the respective rails. Plate Rails 507A, 507B, and 507C can mate with Cassette Assembly 226 by receiving the edges of corresponding Cassettes 228, 230, and 232. Additionally, the walls of Plate Rails 505A, 505B, 505C, 507A, 507B, and 507C may also optionally include notches 506 configured to receive and cradle corresponding rigid fluid conduits 238 when carrier frames 505, 507 mate with cassette assembly 226. Plate rails 505A, 505C, 507A, and 507D may have a closed end and an open end. The open end of the rails may be included to avoid interfering with nearby cassette ports 240 . It should be noted that the first and second support frames 505 and 507 can be slid over the respective edges of the cassette to mate with cassette mount 226 and may not require additional fasteners to mate directly with cassettes 228, 230, and 232. In addition , the safety features that complement the lanes, i.e., features such as, but not limited to, cover-up features Ln / nznz / E / Yi 505F, 505G, and 506 and 508 notches can further strengthen the engagement between the cassette mount and frames, thus allowing any force applied to the frame to be more evenly distributed on the cassette mount, potentially avoiding stressing or distorting the cassette assembly 226. This arrangement can help to compactly install and remove the cassette assembly 226 from a series of manifold receptacles of the hemodialysis machine 246 without causing the cassette assembly to move, leading to misalignment from the cassette ports. The plate rails 505A, 505B, 505C may be interconnected by an upper bar 505D and a lower bar 505E that extend perpendicular to the plate rails. Bottom bar 505E interconnects plate rails 505A to 505B and 505B to 505C at the open end of the rails and near the ports 240 of the cassette. Top bar 505D interconnects plate rails 505A to 505B and 505B to 505C at the closed end of the rails. Similarly, the rails 507A, 507B, 507C are interconnected by an upper bar 507D and a lower bar 507E that extend perpendicular to the rails of the plate. Bottom bar 507E interconnects plate rails 507A to 507B and 507B to 507C at the open end of the rails and near the ports 240 of the cassette. Top bar 507D interconnects plate rails 507A to 507B and 507B to 507C at the closed end of the rails. At least one crossbar 511 may be positioned to connect the first and second carrier frames 505, 507 when the frames are positioned to mate with the cassette assembly 226. In this example, the crossbar 511 is disposed longitudinally through the cassette assembly. cassette 226 and connects the first and second carrier frames 505, 507 at opposite ends of the cross bar. This arrangement helps stabilize the side of frames 505, 507 near ports 240 of cassettes 228, 230, 232. Cross bar 511 helps prevent frames 505, 507 from shifting relative to cassette mount 226 The connection between the respective ends of the cross bar 511 and the corresponding carrier frames 505, 507 may be established by fastening features such as, but not limited to, screws, bolts, adhesive, laser or ultrasonic welding, or other similar fastening mechanisms. . Optionally, the cassette assembly 226 may provide alternative or additional connecting elements between the first carrier frame 505 and the second carrier frame 507 to secure them to each other and the cassette assembly 226, including, but not limited to, clips similar to clips 512 in figure 18, threaded rods or clamps or other elements that limit the degree to which the frames 505, 507 can move relative to each other. Figures 20 and 21 further depict a first support plate 513 and a second support plate 515. The first support plate 513 may be arranged to interconnect the first and second carrier frames 505, 507 in their engagement with the cassette mount. Ln / nznz / E / Yi 226. In the present example, the first support plate 513 is positioned on a side of the cassette assembly 226 that is perpendicular to the sides on which the first and second support frames 505, 507 are located. In addition, the first support plate Support bracket 513 is positioned in the carrier frame on a side opposite the ports 240 of the cassette. The first support plate 513 may additionally include tabs 513A and 513B at opposite edges. These tabs 513A, 513B can be structured to engage the top bars 505D, 507D of the first carrier frame 505 and the second carrier frame 507. The first support plate 513 can be secured to the top bars 505D, 507D mechanically with clips, screws or support plate 513 can be attached to top bars 505D, 507D. Alternatively, the top plate 513 and at least one of the frames 505, 507 can be molded together. The first support plate 513 can be attached to the upper bars 505D, 507D when the carrier frames have been engaged with the edges of the cassettes 228, 230, 232 of the cassette assembly 226. Therefore, the first support plate 513 and the crossbar 511 can secure the first and second carrier frames 505, 507 to each other during their engagement with the cassette assembly 226. The assembly comprising the carrier frames 505, 507, the crossbar 511, and the first support plate attached securely holds the cassette mount 226 and helps to more evenly distribute external mechanical forces to the cassette mount components to avoid distorting their relative positions. First support plate 513 may further provide an inner surface 513D (see Figures 22A and 22B) facing cassette mount 226 and an opposite outer surface 513C, facing away from cassette mount 226. During installation of cassette mount 226, the outer surface 513C of the first support plate 513 can interact with a cassette loading apparatus (not shown) described below. Inner surface 513D and outer surface 513C provide surfaces to which forces can be applied by a cassette loading apparatus to move the cassette assembly as a unit. The first support plate 513 may also provide alignment features to properly load and position the cassette assembly 226 in the loading apparatus. Figure 21 also shows a second support plate 515 that can optionally be included to mate with one of the carrier frames 505, 507 to minimize twisting or flexing of the frames. In the present example, the second support plate 515 is mounted on the second carrier frame 507 and is attached to the frame via connection elements 519. The connection can be achieved by receiving the connection elements 519 in the corresponding connection joints 520 provided in the second support frame 507. In another embodiment, the second support frame 507 may be integrated with a support plate such as, but not limited to, the second support plate 515 as a single component. The bending or twisting of the first carrier frame 505 can also be reduced by including a diagonal cross member 523. The cross member 523 may be an integral part of the structure of the second carrier frame 505 or may be attached to the frame separately. Additional support elements similar to support plates 513, 515 and support bracket 523 can be provided to complement carrier frames 505, 507 and retain the required cassette mounting arrangement 226. Figures 22A and 22B depict perspective views of a first exemplary support plate 513. The tabs 513A and 513B may further provide mating features such as, but not limited to, spring clips or clips 514. The first support plate 513 may also include one or more clips 514 on the non-flange sides. Clips 514 can be constructed to engage the edges of carrier frames 505 and 507. For example, clips 514 can be configured to engage top bars 505D, 507D. Alignment features such as one or more protrusions 516 (FIG. 21) may be included on the edges of the carrier frames 505, 507. The protrusions 516 may serve as alignment features for the slots 514B in the first support plate 513 to ensure proper alignment. proper alignment and connection between the first support plate 513 and the carrier frames 505, 507. In the present example, the first support plate 513 may include longitudinal and / or transverse reinforcements 517 to reduce mechanically induced deformation of the first support plate. support 513. Figure 23 shows a hemodialysis apparatus 246 configured to enclose cassette assembly 226. A front panel 248 is configured to include a dialyzer recess and holder 250, a blood pump cassette receptacle assembly 252, and configured to hold a blood tubing set (not shown). The dialysate cassette assembly 226 is configured to be housed within the apparatus enclosure 246 behind the front panel 248. Figure 24 shows an enclosure 254 for the apparatus 246 of Figure 23, with the front panel 248 and other components removed. The internal configuration of enclosure 254 allows a cassette assembly 226 to be placed on top of the internal shelf 256 of enclosure 254. The interior of enclosure 254 (eg, below shelf 256) is arranged to contain other components, such as a heater for dialysate solution, tubing for various fluid flow paths, a dialysate reservoir or tank, and one or more devices for sensing the conductivity and temperature of the dialysate solution at various stages of mixing. Behind this enclosure 254 is a recess 258 arranged to contain a pressure distribution manifold (in this case a pneumatic actuated manifold) with electromechanical valves, and one or more electronic controllers, at least one of which is configured to control the electromechanical manifold valves. These components are placed outside of the enclosure 254 to help protect them from the high temperatures that can be used when disinfecting the liquid-carrying components of the hemodialysis machine 246. Figure 25 shows a rear perspective view of the Ln / nznz / E / Yi Ln / nznz / E / Yi enclosure 254, noting recess 258, which is located directly below shelf 256 of enclosure 254. Thus, a pressure distribution manifold can be placed directly below a cassette assembly 226, with the cassette assembly located within enclosure 254 and the pressure distribution manifold being located outside of enclosure 254. Load v lock cassette mount Figures 30 and 31 depict the installation and retention of cassette assembly 226 in enclosure 254. In Figure 30, cassette assembly 226 rises just above three cassette receptacle assemblies, with three port arrangements 240 of cassette actuation lined up with their respective receptacle ports on adapters 266, 268, 270. The receptacle assemblies are configured to accommodate the actuation port arrangements of the cassette assembly 226 with actuation outlets from a pressure distribution manifold located out of the enclosure and under the shelf 256. Lowering the cassette mount 226 allows the cassette actuation ports 240 to mate with their respective adapters via a press-fit connection. Sealing of the individual actuation ports 240 can be accomplished through the use of O-rings or gaskets with elastomeric wiper seals or other means typically used to seal press-fit connections. The adapters, in turn, may provide a direct connection to the pressure distribution manifold outlet ports (FIG. 32 to FIG. 37) located below shelf 256 and outer enclosure 254. FIG. 30 further depicts an apparatus 292 for cassette load that the cassette assembly 226 can receive during installation and hold it in place. A handle 308 belonging to the loading apparatus 292, is operable to lock the cassette assembly within the enclosure 254. A detailed description of the operation of the apparatus 292 and handle 308 to lock and retain the cassette assembly will now be provided with reference to Figures 56 to Figure 59. In one configuration, the loading assembly of Figure 30 may be in an open position showing the operating handle extending parallel to and away from the cassette assembly. 31 depicts the cassette assembly 226 locked in the cassette receiving space by indicating that the operating handle 308 is tilted downward, moving the loading apparatus toward the manifold receptacle mounts and thus pressing the cassette assembly 226 into the corresponding adapter ports and securing it there. In the present example, the loading apparatus 292 may comprise force application elements such as, but not limited to, one or more bars that can interact with the first support plate 513 (FIGS. 22A and 22B) and can be operated by the handle 308. Lowering the handle 308 can allow the force applying elements to push the first support plate 513. This force can be transmitted to the cassette assembly 226 through the cassette frames 505, 507, where the frames press the cassette mount 226 into the adapters 266, 268 and 270. Figure 31 represents the cassette mount Ln / nznz / E / Yi 226 in the operational configuration, that is, the cassette mount 226 is pressed to align the array of cassette activation ports 240 with their respective adapters 266, 268, and 270. It should be noted that the handle 308 in Figure 31 is shown in a closed configuration, ie, cassette assembly 226 is locked within enclosure 254, with the handle positioned so that the front panel of the hemodialysis device can be installed without interference. The embodiment of the hemodialysis apparatus 246 shown in Figures 45, 46 comprises an enclosure 254 in which the footprint of the cassette assembly 226 extends in a forward direction and protrudes from the shelf 256. For this reason, a multiple interface group or adapters 266, 268, 270 are configured to extend in a forward direction from shelf 256 as shown in Figure 45. Adapters 266, 268, and 270 provide the required mating of actuation ports 240 of cassette assembly 226 with their respective connectors or receptacle ports 272 located on interfaces or adapters 266, 268, 270. Adapters 266, 268, 270 in this example serve as receptacle assemblies, providing a series of receptacle ports to mate with the cassette ports 240 arranged in each cassette 228, 230 and 232 respectively. Figure 46 shows a bottom perspective view of enclosure 254 with interfaces / adapters 266, 268, 270 installed. The extent to which the adapters protrude from the enclosure shelf 256 (and therefore also from the pressure supply manifold 260) is apparent in this view. The adapters 266, 268, 270 serve to map the cassette ports arranged in an extended direction along the edges of the individual cassettes to a more spatially compact arrangement of manifold ports located on risers or top blocks 276A-C between the adapters 266, 268 270 and an upper block 274 of the underlying pressure distribution manifold 272. pressure distribution manifold Figure 26 shows a schematic representation of one embodiment of a pressure distribution manifold (or manifold assembly). This manifold assembly is arranged to selectively provide pneumatic pressure (positive, negative, or atmospheric) to control pumps and / or pneumatically actuated valves in two separate pump cassettes. In this improved embodiment, a first pneumatic outlet assembly is configured for direct connection to a first pump cassette or cassette assembly (ie, direct connection to the manifold assembly or, to an adapter directly connected to the manifold assembly). In one embodiment, the direct connect interface is schematically illustrated as one or more risers or top blocks 276A, 276B, which are positioned on a top side of manifold assembly 260. The top blocks include direct connect ports 261 configured to connect directly with a first pump cassette (not shown), which can be placed directly on top of the manifold assembly 260. The manifold or manifold assembly also includes a second Ln / nznz / E / Yi mounting of pneumatic outlets configured for indirect connection to a second pump cassette via flexible or malleable tubing. Also shown in Figure 26 is an exemplary fitting 582 for indirect connection to a second pump cassette (not shown), the connection configured for flexible or malleable tubing running a certain distance from the manifold assembly 260 to a second pump cassette. remotely located pump. In the context of the currently described hemodialysis device, the dialysate cassette assembly can be configured to connect directly to the manifold assembly via ports 261, and the blood pump cassette assembly (located further on the front panel of the dialysis device) can be configured for pneumatic connection to the manifold assembly via flexible or malleable tubing to a plurality of fittings (here represented by example fitting 582). Figure 26 also shows another improvement in a manifold assembly 260, which helps prevent or reduce the buildup of particles or liquid debris on the internal sealing surfaces of electromechanical pneumatic control valves. An exemplary valve 267 is shown in a generally horizontal orientation. All internal valve seats or sealing surfaces are oriented to avoid horizontal surfaces where debris can accumulate. In the schematic illustrations of Figures 26-29, a lower or bottom header block 272 mates with an intermediate header block 274. The lower header block 272 has a T-shaped cross section (through the long axis 'Z' of manifold mounting 260), comprising a horizontal portion 272A and a drop portion 272B on which a plurality of valve mounting surfaces and openings are arranged. An exemplary valve 267 is shown mounted to one such surface and over one such opening. It is assumed that a valve face seal (not shown) interconnects the valve body with the mounting surface of the drop portion of the manifold. For convenience, the drop part 272B is shown to have a vertical orientation with respect to the horizontal part 272A. The drop portion 272B can also have a non-vertical orientation, such as one in which the valve mounting surfaces and openings are angled upward, which orients the valve body and face seal in the opposite direction. a downward angled direction. This angled orientation will also help prevent the accumulation of liquid (for example, liquid condensate) or debris on valve components that have sealing surfaces (for example, valve seats). In many (but not all) embodiments of valves, an associated internal valve plunger or piston will operate in a horizontal or near-horizontal direction, which is represented by valve 267 schematically illustrated in Figures 26-29. In the examples shown in Figures 26-29, pressure source lines 263 are shown to be embedded within lower or lower manifold block 272 . Depending on how the internal pneumatic channels are connected in the manifold assembly Ln / nznz / E / Yi 260, these source lines can also be located in the intermediate block 274. In the schematic illustrations shown, each of the plurality of valves 267 receives an input line from one of the pressure source lines 263, and has an output line. output ultimately connected to an output port on the manifold assembly, either a direct connect port 261 or an indirect connect port 582. Fig. 27 shows a schematic illustration of one embodiment of a manifold assembly 260 in which direct connect blocks 276A, 276B protrude, cantilever, or are offset from the main body of the manifold assembly. In this illustration, the long axis (Z) of the manifold assembly can be made to accommodate a pump cassette of any arbitrary length in the long axis direction. But if the pump cassette is configured to also have an inlet port assembly that exceeds the front to back ('X') major dimension of the manifold assembly, the direct connect blocks can be arranged to protrude from the manifold assembly. collector in that direction. Ports 261 can then be connected to channels within blocks 276A,B to be routed to a more compact arrangement of one-to-one mapped ports on top of middle block 274. Figure 28 shows a schematic illustration of one embodiment of a manifold assembly 260 in which a series of pressure sensor ports 567 have been positioned between direct connect blocks 276A and 276B. In this case, various pneumatic channels within the manifold assembly may have branch or in-line connections to the 567A sensor ports of a 567 pressure sensor array. In most (but not necessarily all) cases, these channels They connect to the outlet line of a pneumatic control valve and to an outlet port on the manifold assembly to which the valve outlet line is connected. In one example, an array of pressure sensing ports can be configured to mate with a printed circuit board (PCB) positioned on top of the die and including a corresponding array of pressure sensors. The pressure sensors on the PCB can be connected to a hemodialysis controller that uses pressure information to control pneumatic control valves to deliver a predetermined pressure level and pattern to a pump or valve object on a connected pump cassette. 29 shows a schematic illustration of one embodiment of a manifold assembly 260 that includes one or more manifold adapters or interface blocks 266, 268. In this example, the upper blocks 276A, 276B function as risers to provide clearance between a installed direct connect pump cassette and the main body of the manifold assembly 260. The risers may include pneumatic channels that connect a plurality of valves in the manifold (such as valve 267) to manifold adapters or interface blocks 266, 268 for finally connect to an associated pump cassette. Manifold adapters or Ln / nznz / E / Yi interface blocks can be configured to spatially redistribute output ports 261a, which are relatively close together in a riser block or in the other collector blocks, to an array of 261b output ports spaced apart. different way. In this manner, the direct connect output ports of the manifold assembly can be spatially arranged or redistributed to match the corresponding inlet ports of a mated direct connect pump cassette. Manifold adapter 266, 268 thus includes transfer ports on a first side facing and mating with manifold 274 or its associated riser 276A,B, which map to corresponding transfer ports 261b on a second opposite side facing and mates with a pump cassette assembly. Thus, a first series of manifold output ports having a first space port configuration can be directly coupled to a second series of cassette input ports having a second space port configuration. The mapping between the corresponding transfer ports is accomplished by routing internal channels within the manifold adapters 266, 268. In this case, the spatial arrangement of the manifold or riser output ports has a length that is less than the length of the spatial arrangement of the manifold adapter transfer ports on the second side of the adapter. The result is that the manifold adapter protrudes from the front side of the manifold in the form of a cantilever. These features help to decouple the spatial and dimensional constraints of a pump cassette assembly from those of a manifold assembly configured to drive the cassette(s) of the pump cassette assembly. In current embodiments, a manifold assembly can be made as compact as valve, channel, and port restrictions allow, while retaining the ability to interface with a pump cassette that may have substantially different space restrictions or spatial matrix requirements of its ports of action. Figures 32, 33 show the details of one embodiment of a pneumatic actuation manifold in the form of a pressure distribution module 260. The pressure distribution module 260 provides a selectable pneumatic connection of a plurality of pressure sources to the cassette assembly which connects to the receiving ports on the manifold adapters 266, 268, 270 pad. pressure 260 may further provide a selectable pneumatic connection to a remote cassette via flexible or pliable pneumatic lines (not shown). The pneumatic connections are selectively controlled by digital or binary pneumatic valves 262, 265, 267 mounted in or on the manifold blocks. One or more controllers monitor the status of the valves based on signals received from pressure sensors mounted in the upper block 276 and, in the case of a hemodialysis machine, provide programmed instructions to selectively activate the valves and pump blood, dialysate and water in order to administer a dialysis treatment to a Ln / nznz / E / Yi patient. The Pressure Distribution Module 260 controls the action of pneumatically actuated diaphragm pumps and pneumatically actuated liquid valves by selectively connecting to one or more pressure vessels through digital or binary electromechanical valves. Electromechanical valves may comprise digital two-way or three-way valves. Digital valves can have two positions. A two-way digital valve is open or closed. A three-way digital valve connects a common port to a first or second port. One or more controllers control the status of valves 262, 265, 267 based in part on signals received by the one or more controllers from pressure sensors 565 (see Figure 34). Pressure vessels may include a high positive pressure vessel, a low positive pressure vessel, a negative or vacuum pressure vessel, and a vent to atmosphere. Pressure distribution module 260 can be assembled from a plurality of manifold blocks. The pressure distribution manifold 260 of Figures 32, 33 comprises a T-shaped manifold block 272, an intermediate manifold block 274 and an end manifold block 276. The pressure distribution manifold 260 further comprises valves 265 cartridge valves mounted on the center manifold block 274 and surface-mounted valves 267 that mount on the vertical arm of the T-shaped manifold block 272. The arrangement of pressure vessel ports 263, the first valve assembly 265 and second valve assembly 267 may be horizontal with respect to faces 272F, 274F, and 276F (FIG. 33) belonging to manifold blocks 272, 274, and 276, respectively. This arrangement can help prevent debris or fluid buildup on the valves that can potentially affect their function or shorten their life without maintenance. Pressure sensors 565 (Figure 34) are mounted to ports 567 on an upward facing surface of end manifold block 276. Adapters 266, 268, and 270 provide ports 266P, 268P, 270P to receive mounting ports 240 cassette 226. Intermediate manifold block 274 and T-manifold block 272 may include internal supply lines for atmospheric pressure, low positive pressure, high positive pressure, and negative pressure. One or more of these internal supply lines run the length of the manifold blocks 272, 274. The ports for the internal supply lines are plugged 264 or have a port 263 for a flexible tube connection to a pressure vessel. Both end faces of the manifold blocks 272, 274 may include ports for connecting internal supply lines (not shown) to external pressure vessels. A plurality of diaphragm pumps and diaphragm valves can be grouped into a single cassette as shown in Figures 6 through 13. A plurality of such cassettes can be joined together to form a cassette assembly 226 as shown in Figures 20, 21. In this In the Ln / nznz / E / Yi case, the mounting separates the cassette spaces to accommodate external pumps, mixing chambers or fluid balance chambers have larger volumes than can be accommodated within any of the individual cassettes. The pressure distribution module 260 includes adapters 266, 268, 270 which extend at right angles to the long axis of the manifold blocks 272, 274, 276. The adapters extend the interface area of ​​the pressure distribution module from the footprint of the manifold and riser blocks to any area required to accept the ports 240 of the cassette assembly 226. The pneumatic design and port layout on and within adapters 270, 268, and 266 and their subcomponents (not shown) allow for direct connection between cassette assembly 226 and manifold blocks 272, 274, 276, with one-to-one mapping. one of each port on the cassette mount with the corresponding actuation ports on the manifold mount. External pressure vessels to which the pressure distribution module 260 may be connected may have volumes maintained at specified or predetermined pressures by pumps controlled by a system controller. In one embodiment, a high pressure reservoir can be maintained at a pressure of approximately 1050 mmHg, and a positive pressure reservoir can be maintained at a pressure of approximately 800 mmHg. The pressures actually supplied to the various pumps and pneumatically actuated valves may vary depending on the pressure reservoir carried by the two-way and three-way valves in the pressure distribution module 260. In addition, intermediate pressures can also be supplied by a combination of fast opening and closing of the on and off valves. Generally, a high-pressure source can be useful to actuate diaphragm valves to ensure reliable, leak-free valve closure during cassette assembly operation. Figure 33 represents an exploded view of the pressure distribution manifold 226. The manifold blocks 272, 274, and 276 may further comprise intermediate elements that connect features between each of the manifold blocks 272, 274, and 276. These intermediate elements and connection features may assist in assembling the three manifold blocks and establish a pneumatic connection between them. the individual manifold blocks 272, 274, and 276. A first set of intermediate components may include, for example, a first plate 550, a first gasket 552, and a second gasket 554 that may be used between the T-shaped manifold block 272 and the intermediate manifold block 274 and a second set of intermediate components may include a second gasket plate 555, a third gasket 556, and a fourth gasket 558 positioned between the intermediate manifold block 274 and the end manifold block 276. two manifold blocks 272, 274 can be clamped together with an intermediate plate 550 sealed between them. Intermediate plate 550 may also be referred to as a backing plate, as it provides a rigid surface that forces the gasket to seal against Ln / nznz / E / Yi multiple channels can be provided in end header block 276, T header block 272 and intermediate header block 274. Each header block 276, 274, 272 may comprise at least single sided 276G, 274F, 272F (see Figures 33, 35, 36) with channels and multiple ports that mate with ported and gasketed boards, such as boards 550, 555 and gaskets 552, 554, 556, 558. respective channels can be configured as slots including a solid bottom and two side walls with an open top. The channel may be cut into a manifold block face 276F, 274F, 272F or may be formed with walls extending above the surface of the manifold block face 276F, 274F, 274G, and 272F. As shown in Figure 33, the open top of the channels can be sealed by holding a gasket 554,552, 556, 558 backed by a rigid flat intermediate plate 550, 555 against the channels. In one example, intermediate plate 550 is a backing plate that forces gasket 552 against all channels in face 272F and gasket 554 against channels in face 274G. Note that face 274G is opposite face 274F in Figure 33. The manifold block and gasket may include features to ensure essentially uniform pressure distribution across the gasket. Intermediate plate 550 provides a substantially smooth and rigid backing for the gaskets so that more than one manifold block can be assembled or sandwiched in the multi-part air manifold 260. The channels are linked to pressure sources, valves, sensors, and outlet ports that reside on other faces of the blocks. Manifold blocks 276, 274, 272 may sandwich gaskets 552, 554, 556, 558 and intermediate plate 550, 555 with each other with mechanical fasteners 570 to seal multiple channels in channel faces 272F, 274F, 274G, 276G of each one of manifold blocks 272, 274, 276. This sandwich construction allows compact mounting of multiple manifold blocks with channel mounts on one face of each block 272, 274, 276. The connection points of the Ul T-shaped manifold block may be configured to receive bolts that extend through other components that assemble the pressure distribution manifold 260 as a unit. In this example, matching connection points 572 can be provided on the first gasket plate 550, connection points 573 on the intermediate manifold block 274, connection points 573 on the third and fourth gaskets 556, 558. The first assembly of Valves 265 can operate in air paths within manifold blocks 272, 274 and 276 and / or air paths connecting manifold blocks 272, 274 and 276. Figures 32 and 33 show an embodiment that includes a plurality of cartridge valves 265 and connections to pressure vessels 263. A cartridge valve is inserted into a manifold port. Corresponding cavities (not shown) are formed to accommodate seals on the exterior of cartridge valves 265. The machined cavity may have a set of dimensions defined by the valve manufacturer to ensure proper sealing and function of the cartridge valve 265 . Although in other embodiments the numbers may vary, in this particular embodiment, approximately forty-eight cartridge valves 265 are mounted to one side face of the intermediate manifold block 274. This side of the intermediate manifold block 274 is perpendicular to the ducted face 274F. In some embodiments, the cartridge valves are three-way valves, such as the plug-in Lee LHDA valves available from The Lee Company USA, Westbrook, Connecticut. The number of electromechanical valves is determined by the number of individual diaphragm valves and pumps to be operated in a direct connect cassette assembly and a remote connect cassette assembly (if desired), and the linear arrangement of the valves. electromechanical valves results in the extended length of the manifold assembly. Referring now to Figure 34, the pressure distribution manifold can serve as a pneumatic actuation device for components other than the cassette assembly 226. For example, pressure distribution manifold 260 may also be in pneumatic communication with other pneumatically actuated valves, diaphragm pumps, pneumatic cylinders, and remote cassettes comprising diaphragm valves and diaphragm pumps. In one example, pressure distribution module 260 controls the position of an occluder 251 in Figure 23, the occluder comprises a pinch valve to block blood lines and actuated by a pneumatic cylinder. In another example, pressure distribution module 260 may be placed in pneumatic communication with a dialysate tank to perform tank volume measurements using pressure information. In addition, the pressure distribution module 260 may be arranged to control the pumping action of a blood pump cassette (not shown) that mounts to the blood pump cassette receptacle assembly 252 in Figure 23. With Referring now to Figure 34, the ports 582 shown on the T-shaped manifold block 272 may be connected to one or more blood pump cassettes directly or via flexible or malleable tubing to establish the required pneumatic connection. The 582 ports include fittings that connect to a pneumatic tube and may be individually removable from the 272 T-shaped manifold. Pneumatic lines connected at one end to the 582 ports may connect at a second end to a connector on the surface of the wall 255 (FIG. 24) of the dialysis machine. A second connector within the housing can then make a connection using flexible tubing to, for example, a dialysate tank, a pneumatically actuated tube occluder, and / or a blood pump cassette receptacle assembly 252. Cartridge valves 265 and surface mount valves 267 in this example control the pneumatic pressure supplied to the occluder, blood pump cassette, and other pneumatically actuated elements in hemodialysis machine 246. can be Ln / nznz / E / Yi Ln / nznz / E / Yi provide mounting features such as standoffs 580 to attach pressure distribution module 260 to the rear wall of enclosure 254 and to establish the location of adapters 266, 268, 270 relative to enclosure 254. Continuing with reference to Figures 34, 35, the valves 267 disposed in the T-shaped manifold block 272 are electromechanical valves that seal against a flat surface or a surface machined to accept the valve face. In some embodiments, the surface mount valves 267 may be proportional valves or continuously variable valves (also called variable valves). In other embodiments, surface mount valves 267 are binary two or three way valves. In some examples, surface 272F is generally horizontal, making the arm of the T-shaped cross section of manifold 272 generally vertical. In a preferred arrangement, the foot valve mounting surface is vertical or slightly upwardly angled so that the valve ports 267 are horizontal or downwardly angled to prevent debris or liquid buildup. Sealing features such as O-rings and / or other items may be provided on the valves to prevent fluid or air leakage. The valves can be any two-way or three-way digital valve suitable for surface mounting, such as model 11-15-3-BV-12P-0-0 from Parker Hannifin Corporation of Hollis, N.H. Referring now to Figure 34, the pneumatic flow in the pressure distribution manifold 226 can be monitored through one or more pressure sensors, these sensors can be mounted on a sensor board (eg, PCB). . In the present example, sensor board 560 may be positioned on a surface 567 of an upper manifold block 276, in the spaces between risers 276A-C. Pressure sensors 565 may be mounted directly to face 276F of first end manifold block 276 . The pressure sensors 565 may be integrated circuits soldered to a printed circuit board (PCB) 560. As shown in Fig. 34, a printed circuit board 560 including one or more pressure sensors 565 may be mounted on the face 276F that is parallel to the grooved face of the second end manifold block 276 with a gasket to pneumatically isolate each sensor, and with a plate (not shown) to hold the PCB 560 in place and compress the gasket enough to seal each pressure sensor from atmosphere. Sensor plate 560 may be engaged with end manifold block surface 567 through fastening components such as screws, nut-bolt pairs, rivets, adhesive, or a combination of such fastening mechanisms. An example 565 pressure sensor may be obtained from Freescale Semiconductor, Inc. in Tempe, Arizona (part number MPXH6250A). The PCB including a plurality of pressure sensors 565 can be mounted as a unit on the end manifold block 276. The pressure sensing face of each pressure sensor 565 can be fluidly connected to pressure sources Ln / nznz / E / Yi desired such as reference volumes or more remotely to the actuation chambers of the diaphragm pumps, or to a dialysate storage tank. In some cases, sensors are arranged to monitor liquid pressures in various diaphragm pumps in liquid handling cassettes. End manifold block 276 provides risers 276A, 276B, and 276C that can interface with respective adapters 270, 268, and 266. The manifold assembly is constructed such that sensor plate 560 avoids interfering with the mating between the risers and the corresponding adapters. The risers also provide clearance between the upper liquid handling cassette assembly and the temperature sensitive sensor board 560, allowing placement of insulation 269A between the two (see, for example, Fig. 48). Figures 36 and 37 illustrate the second manifold block 276 with a face 276F and a base surface 276G. The 276G base surface can be configured to mate with one or more intermediate components, such as gaskets, gasket plates, and / or other manifold blocks. As shown, base surface 276 may comprise a plurality of pneumatic channels 574 that are sealed by gasket 558 (FIG. 33). In some examples, channels 574 may connect pressure ports 567 on face 276F to ports 261A, 261B, 261C in risers. In other examples, channels 574 may connect pneumatic pathways or holes through joint 558 to pressure ports 567 or holes 261A, 261B, 261C. Face 276F may comprise risers 276A, 276B, and 276C that can serve as mounting surfaces for corresponding adapters 270, 268, and 266, respectively. The 261A, 261B, and 261C pneumatic ports, on the 276A, 276B, and 276C lifters, can interface with the respective adapters 270, 268, and 266 to transmit pneumatic pressure to the 226 cassette assembly. The secure connection between the 261 vertical ports and the adapters it can be established by means of mechanical accessories such as pairs of nut-bolts, threaded or push screws or similar mechanisms. Mechanical assembly may also include mating the blocks with intermediate components such as one or more gaskets 568 (FIG. 32), gasket plates, and / or similar components. Pneumatic connections on the manifold The structure and function of the manifold 260 of Figure 32 can be better understood by examining the pneumatic pressure sources, conduits, valves, sensors, and outlet ports of the manifold 260. In one example presented in Figure 32, the manifold 260 has dozens of valves, sensors, and ports. The following section 3 describes exemplary routes comprising sources, valves, conduits, ports and, in one example, a pressure sensor. The example routes serve to illustrate how the manifold elements of Figures 32 and 33 are joined to provide selectable fluid connections between the pressure sources and the actuation chambers of the figures. Ln / nznz / E / Yi air operated valves and pumps, and provide fluid connections to pressure sensors. Pressure sensors provide information to a controller that controls valves to safely pump blood, dialysate, and water to provide therapy to a patient. The pneumatic manifold schematic in Figure 38 depicts the pneumatic connections to a blood pump cassette. (The blood pump cassette in this case is located on a front panel of the dialysis unit, so it is connected to the manifold by flexible tubing instead of a steering connection.) The pneumatic circuits of Figure 38 selectively connect the blood actuation chambers and heparin pumps and associated valves to the high positive pressure source HP, the low positive pressure source LP, or the negative pressure source NEG. Circuit 1005 connects a blood pump BP1 to a pressure sensor P_BP1, the low pressure source LP through the valve V_BP_POS1 and the negative pressure source NEG through the valve V_BP_NEG1. The actuation circuit of the blood pump 1005 in the manifold 260 is presented in figures 39, 40. The flow paths are the orifices and channels of the different blocks of the manifold 260. The low pressure source LP is a conduit in the horizontal portion 272A of the tee header running along the length of the tee header block 272. The source of negative pressure NEG is a conduit parallel to LP through the long axis of the tee header block 272. Positive pressure flows from the LP conduit through the flow channel 1012 which is located at the top of the tee header 272, then through an orifice 1020 through the vertical leg 272B of the tee header to the electromechanical valve V_BP_POS1. When valve V_BP_POS1 opens, positive pressure flows up through port 1025, which is in vertical leg 272B to channel 1040 located at the top of tee manifold 272. Low pressure then flows through port 1060 to port 582, where a fitting allows a flexible or malleable line to connect the port to the blood pump cassette (remote). The pressure in the blood pump connected to port 582 is monitored by a pressure sensor mounted on port P_BP1. Port BP1 is located at the bottom of the two upward facing surfaces of upper manifold block 276. Port P_BP1 is fluidly connected to channel 1040 through hole 1057 in upper manifold block 276, a channel 1055 on the top of intermediate manifold block 274 and a hole 1050 through intermediate manifold block 274. Shown embedded in manifold assembly 260 in Fig. 40, in circuit 1005, T-manifold block 272 selectively connects an actuation chamber on a blood pump cassette (plugged into cassette receptacle 252 in Fig. 23) to the low pressure source LP or the negative pressure source NEG through two valves. A pressure sensor mounted in the upper manifold block 276 is fluidly connected through orifices and Ln / nznz / E / Yi channels in the upper and middle header blocks. Other pneumatic circuits may connect actuation chambers for the diaphragm pumps in cassette assembly 226 to two of the low pressure LP, atmospheric ATM, and negative pressure NEG sources through valves in the vertical leg 272B of the manifold block in T 272. The pneumatic schematic of Figure 41 depicts the pneumatic connections to the various actuation ports of the cassette assembly 226. The pneumatic circuits in Figure 41 selectively connect the actuation chambers of the various valves (and the two diaphragm pumps illustrated here) in an external dialysate cassette (ODC) to at least one of the atmospheric pressure ATMs, HP high positive pressure source, LP low positive pressure source and NEG negative pressure source. Circuit 1100 is an example pneumatic circuit that connects the V_MIX_DT diaphragm valve on the ODC cassette to ATM or LP pressure sources through an 1105 3-way valve. Circuit 1200 is an example pneumatic circuit that connects the V_DISINFECTION liquid valve on the ODC cassette to the HP or NEG pressure sources through a 1205 3-way valve. The Mix_DT 1100 valve circuit and the DISINFECT 1200 valve circuit in the manifold 260 are presented in Figures 42, 43. The flow paths comprise the orifices and channels of the various blocks of the manifold 260. The sources of pressure, ATM, NEG, LP, HP, are conduits arranged along the long axis of the middle block 274. The DT_MIX circuit 1100 connects the LP low pressure source or the ATM atmospheric source to the DT_MIX_V_output port for the DT_MIX liquid valve in the assembly. cassette 226. The LP low pressure source is connected to valve 1105 through a channel 1110 in the underside of intermediate manifold block 274 and orifice 1115. The ATM atmospheric source is connected to valve 1105 through a channel 1140 in the underside of the intermediate manifold block 274 and orifice 1145. Valve 1105 is connected to the V_Mix_DT outlet port through channel 1120 in the top of the intermediate manifold block. medium 274, the 1130 hole through the top manifold and the 1135 hole through the 268 adapter. The SANITIZE circuit 1200 connects the high pressure source HP or negative source NEG to the V_SANITIZE output port for the SANITIZE liquid valve in the cassette assembly 226. The high pressure source HP is connected to the 1205 valve via a channel 1210 in the underside of intermediate manifold block 274 and orifice 1215. The negative source NEG is connected to valve 1205 through a channel 1240 in the underside of intermediate manifold block 274 and orifice 1245. The valve 1205 is connected to output port V_DISINFECTION through channel 1220 at the top of the intercooler block 274, port 1222 through intercooler 274, channel 1224 at the bottom of the intercooler, port 1226 to the rear through the intermediate collector, the channel Ln / nznz / E / Yi 1228 on top of intermediate manifold, hole 1230 through upper manifold 276 and through adapter rail 268 through retainer 1235 and channel 1237. Figure 43 shows how the above circuitry is physically integrated within the manifold assembly 260. Also shown is the mapping of these actuation ports from one arrangement on riser 276B to a spatially different array of multiple adapter actuation ports 268, providing an array of actuation ports matching the array of actuation ports of the 226 cassette assembly. Figure 44 illustrates the pressure distribution manifold 260 installed in the recess 258 of the enclosure or housing 254. This arrangement may allow proper alignment between the ports 261 on the risers of the pressure distribution manifold 260 and the respective ports on the mating surface of adapters 266, 268 and 270. In present embodiments, manifold 260 is positioned below some thermal insulation 264. Insulation 264 may be provided between manifold body 260 and shelf 256. This arrangement isolates components electronics sensitive to the temperature of hot fluids circulating in the components within the enclosure or housing 254. As shown in Fig. 45, in this embodiment of the hemodialysis apparatus 246 and enclosure 254, the footprint of the cassette assembly 226 extends forwardly from a front face of the apparatus 246. Referring to a user or operator in front of the apparatus 246, the footprint of the cassette extends over the front edge of the shelf 256. For this reason, one or more adapters 266, 268, 270 are configured to provide the required engagement of the activation ports 240 of the cassette assembly 226 to their respective connectors or receptacle ports 266P, 268P and 270P located at interfaces or adapters 266, 268, 270. Adapters 266, 268, 270 in this example serve as receptacle assemblies, providing a first spatial arrangement of receptacle ports for mate with the identically arranged cassette ports 240 of each cassette 194, 196 and 198 respectively of the cassette assembly 226. Figure 46 shows a perspective view a from below enclosure 254 with interfaces / adapters 266, 268, 270 installed. The extent to which the adapters protrude from the enclosure shelf 256 (and therefore also from the underlying pressure supply manifold 246) is apparent in this view. Figure 32 shows how the adapters 266, 268, 270 mount to the top side of the 276A-C manifold risers, and how they protrude from the front side of the 260 manifold. The first space mounting of 266P, 268P, and 270P receptacle ports connects to a second (in this case more compact) spatial assembly of outlet ports 261 of the top block or riser 276A-C of manifold 260. Internal channels within adapters 266, 268, 270 are routed to respective risers 276A , 276B and 276C mounted on a corresponding arrangement of manifold outlet ports. Figure 52 shows the manifold / adapter assembly with adapter 266 removed and exploded to fully reveal the construction of the adapters, as well as risers 276C, 276A, and 276B. Figures 47, 48 are rear views of manifold 260 and illustrate that lifters 276A, 276B, and 276C allow adapters 266, 268, 270 to slide into their respective positions in enclosure 254 from the rear of the enclosure through slots or cutouts 280, 282, 284 of shelf 256 of enclosure 254. Risers 276A, 276B, and 276C are made high enough to allow placement of insulation, whether rigid foam insulation or other insulation, to provide a thermal barrier between the shelf 256 and the collector body 260, as well as the electronics (control boards, sensors, etc.) located in the recess 258. (See, for example, the 269A insulation wrapped around the risers in Figure 48) . Figure 48 shows how an assembly comprising manifold 260, its attached risers and adapters 266, 268 and 270, along with other related components, can be slid into position as a group in recess 258 of enclosure 254. Figures 49 through 51 illustrate the coupling between the adapters and their respective rails in which the adapters are located within the enclosure to receive the cassette mount from the cassette loading apparatus within the housing 254. The adapter receptacles or rails Adapters 591, 593, and 595 may be integrated with shelf 256 of cabinet 254 or may be separate components that can be mechanically attached to cabinet 254. In one embodiment, shelf 256 includes spaces to receive or attach adapter rails 591, 593, or 595. Figure 48 specifically depicts a rear (exterior) view of enclosure 254 with adapters 266, 268, 270 partially inserted into respective adapter rails 595, 593 and 591 (shown in Figure 49). Manifold 260 is attached to adapters 266, 3268, 270 before the manifold / adapter assembly is slid into its final location in enclosure 254 as defined by the adapters and adapter rails. As shown in figure 49, lanes 591, 593 and 595 are located in spaces 591S, 593S and 595S respectively. Figure 49 depicts a front (inside) view of adapters 266, 268, and 270 partially received in their respective adapter rails in enclosure 254. Proper alignment of adapters 266, 268, 270 and pneumatic manifold 260 can be important to ensure that the plurality of pneumatic ports 240 of cassette assembly 226 align with corresponding receptacle ports 266P, 268P, 270P to provide the connection required for cassette mounting 226. The final positioning of the adapter is defined by adapter rails that are positively mounted to the same enclosure that mounts the cassette magazine 292 to the ceiling of enclosure 254. As a result, the retaining mechanisms for the components mentioned above should be placed Ln / nznz / E / Yi appropriately to achieve alignment of the pneumatic ports between the three mounts, ie, the cassette mount 226; adapters 266, 268, 270 and air manifold 260. Figure 50 depicts a cassette loader 292 with an operating handle 308. Cassette loader 292 may be mounted to an interior surface of a ceiling 604 of housing or enclosure 254. As illustrated, cassette magazine 292 and adapter rails 591, 593, and 595 are positioned on opposite surfaces of enclosure 254 and maintain a fixed spatial relationship to one another. Figure 51 depicts an example adapter rail 591 which may comprise a headrest or flange 592 and a tray portion 597 with a raised platform 596 which may partially or completely occupy the tray portion 587. The headrest 592 with the tray portion 597 forms a frame of the rail 591. The tray portion 597 can receive the corresponding adapter, and the corresponding adapter can rest on the raised platform 596. The tray portion 597 can also comprise fence contours 594 that can be curved according to the edges of the rail. corresponding adapter received in the rail 591, so that the adapter can be slid down in the receiving rail. In this embodiment, the tray portion 597 may further provide a cut-out region 597 where the received adapter may interact with a corresponding riser on the air manifold 260. Optionally, slots or elongated slots 611 may be provided between the sides of the raised platform. 596 and fence contours 594. The elongated slots 611 can collect any escaping liquid and help divert any escaping liquid or condensation from the top surface of an installed adapter, which could potentially reach electronics. arranged below the shelf 256 or in the area of ​​the recess 258. Figures 52 and 53 depict an exploded view of an example adapter 266 and its interaction with the corresponding riser 276C. More specifically, Figure 52 depicts a top-down view of the plurality of plates and gaskets that can collectively form adapter 266. And Figure 53 depicts a bottom-up view of the same exploded view of adapter 266. an adapter for providing individual pneumatic paths between the first port assembly of the cassette assembly 226 and the second port assembly of the pneumatic manifold 260. In this example, the pneumatic ports 240 on the cassette assembly are distributed over an extended surface area away from the narrow dimension of the manifold assembly 260. The adapter acts to converge this larger first spatial assembly into a smaller spatial assembly of the pneumatic ports 261 on the manifold risers 260. As illustrated in Figures 52 and 53, the exemplary adapter 266 may comprise a plurality of layers or plates comprising apertures and pneumatic channels conv they emerge in a smaller surface as the layers advance towards the respective elevator. The top plate 280 of the adapter 266 includes pneumatic ports 271 and Ln / nznz / E / Yi Ln / nznz / E / Yi connection features to mate with adapter backplates. The pneumatic ports 271 and connection features 293 can be seen through the top view of the top plate 280 in Figure 52, and through the bottom view of the top plate 280 as shown in Figure 53. The top plate 280 rests on an intermediate block 286 that includes corresponding pneumatic ports 285 on its first surface 286A. These air ports 285 mate with air ports 271 on top plate 280. A brush seal 282 may be received in a seal receptacle 281 embedded in a first surface of intermediate block 286. Continuous elastomeric seal 282 may be formed from a mold, with wiper seals 284 appropriately located. Wiper seals 284 provide sufficient sealing engagement between the cassette ports 240 and the mating adapter receptacle ports 271, while providing less frictional resistance for cassette mounting installation and removal 226 than, for example , the individual O-ring seals. 53 depicts a second, opposed surface 286B of intermediate block 286. This surface includes pneumatic channels 286C in fluid communication with ports 281 on first surface 286A. Channels 285C may be arranged to converge and connect pneumatic ports 281 on first surface 286A to distributed pneumatic ports on second surface 286B. As shown, the second surface air ports 286B occupy a smaller area and a different spatial arrangement compared to the first surface air ports 286A. Channels 285C ensure that air ports 281 converge or offset toward the adapter riser side port arrangement 266. A second intermediate block 290 may include air ports 288 to match the arrangement of air ports provided on the second surface 286B. of the intermediate block 286. A second gasket 289 may be placed between the first intermediate block 285 and the second intermediate block 290. The gasket 289 may allow a proper seal between the first intermediate plate 286 and the second intermediate plate 290, and allow the gasket compressed enough to create a seal. In one embodiment, a set of alignment features may be provided on the joint 289 as well as on one or both of the adjacent plates. In this case, the plates may be the first intermediate block 286 and the second intermediate block 290. Additionally, a transition joint 289 may include pneumatic ports corresponding to the pneumatic ports 285 on the first intermediate block 286 and the pneumatic ports 288 on the second. second intermediate block 290. A riser joint 291 may be placed between the second intermediate block 290 and the corresponding riser, which in this example is the riser 276C. This gasket is arranged to seal the interaction between the second intermediate block 290 and the riser 276C. A plurality of joint alignment features can be provided in Ln / nznz / E / Yi the mating surfaces of the second intermediate block 286 and the elevator 276C. The above description is intended to also apply to adapters 268, 270 and interactive elevators 276B and 276A. The number and spatial distribution of pneumatic ports in the other modalities of adapter-elevator interaction can and do differ. Sealing components between the ports often include O-rings when there is pneumatic interaction between the ports. In the case of adapters, a plurality of O-rings may be used to ensure a sealing fit between the mating ports. However, a plurality of spatially arranged O-rings can exhibit relatively poor alignment tolerances when a plurality of pneumatic ports 240 are inserted into corresponding adapter ports. In addition to tolerance issues, a plurality of O-ring connections can create a greater than desirable mating / disengaging force between the cassette assembly 226 and its associated adapters. In an alternative arrangement, a web of cam joints can be used to make the required seal, and can be installed between two interactive plates or blocks of an adapter. Figure 53 illustrates an exemplary cam seal 284 that can be molded as a single unit, thus substantially simplifying assembly and installation procedures. Figure 54 depicts an exemplary cam joint used on one of the manifold adapters. Figure 55 shows a cross-sectional view 33H of the cam seal of Figure 54. As illustrated, seal 284 can be formed to annularly surround port 285 and form a periphery tapered gap toward air port 285. Seal 284 may optionally include an annular nodule or ridge 283 built into cam seal 284 to cover a portion of port 285. This arrangement and construction of cam seal 284 may allow insertion of cassette ports 240 with a acceptable amount of force, and can also ensure a seal between the adapter and the cassette during operation (ie, during the application of positive and negative pressure through the adapter ports). Figure 56 and Figure 57 show a cassette seat or cassette loader apparatus 292 used to secure a first side of cassette mount 226 in order to move the cassette mount linearly toward or away from one or more mounting arrangements. receptacle assemblies arranged to mate with a corresponding arrangement of cassette ports 240 on one or more of cartridges 228, 230, and 232 on a second opposite side of cassette assembly 226. In the example described below, the receptacle assemblies include 266, 268, 270 manifold adapters, but the cartridge loader can be used in any other system where a ported cassette will be plugged in and out of any type of receptacle arrangement, including, for example, a fixed multiport receptacle or a mobile plug equipped with an array of ports, among other possibilities. The receptacle ports to which the input ports connect. Ln / nznz / E / Yi cassette actuation can also be arranged in a frame, housing, or even directly on a manifold output port arrangement, instead of the exemplary adapters 266, 268, 270 shown, if the two sets of docking ports can be arranged to be correctly aligned. The cassette seat apparatus 292 has a generic utility for assisting a cassette with external ports to mate or undock from docking connectors or receptacle ports on any device. Figure 56 shows cartridge magazine 292 in a retracted position, which moves the cassette assembly linearly away from receptacle ports 261b of Figure 29, or ports 266P, 268P and 270P of Figures 30, 32, 45, or more generally the ports 271 of Figure 52, which in this example are arranged in adapters 266, 268, 270. Note that the cassette seater or cassette loader 292 can be used to seat or unseat a cassette. or cassette mounting into or from a receptacle mounting, provided that a single cassette or group of cartridges has fluid or actuation ports on a side opposite that of a side secured by the cassette seating apparatus 292. In this example, the cassette seating apparatus 292 comprises a stationary frame 294 including stationary members 296a,b. Stationary members 296a,b are coupled to a link which, in turn, interacts with a movable cassette mount 298. The movable cassette mount 298 is configured to contain a cassette or cassette mount, and in this example comprises a flange 300a,b leading to a cassette mounting rail 302a,b. In this example, cassette mounting rails 300a,b allow a cassette or cassette mount to be slid into position on seating apparatus 292 and clamped. Other examples may include a clamping apparatus that can clamp the cassette or cassette mount. In this example, the independent movement of an installed cassette or cassette assembly is limited by the presence of one or more crossmembers 304 that limit the movement of the upper side of the installed cassette or cassette assembly, and by the actuator arms 306a,b of an operating handle 308, actuator arms 306a,b are moved into a position to interfere with lateral movement of an installed cassette or cassette mount. As shown in Figures 56-58, the connection may comprise two or more rocker arms 310a,b, each of said rocker arms pivotally connected 312 at a first end to stationary members 296a,b. Each of the rocker arms 310a,b is arranged to move in a plane generally parallel to the direction of movement of the cassette mount 298 with respect to the stationary member 296a,b. A second end of each rocker arm 308a,b comprises a hub 316 coupled to a shaft or pinion 318, the shaft / pinion configured to interact with flange 300a or 300b being generally parallel to a plane of motion of the rocker arm 310a,b . Shaft or pinion 318 is positioned within a slot elongated Ln / nznz / E / Yi 320 on the flange 300a or 300b which translates an arcuate movement of the second end of the rocker arm 310a,b towards or away from the stationary member 296a,b into a linear movement of the cassette mounting rail 302a, 302b toward or away from the stationary member 296a, 296b. In this example, shaft or pinion 318 optionally extends from flange 300a to flange 300b to also serve as crossmember 304. Shaft or pinion 318 may slidably interact with slot 320, or by other means (such as, for example, through a circular bearing or a wheel placed in the slot 320). To help ensure linear movement of cassette mount 298, one or more guide elements (such as, for example, post 322) may optionally be included to limit lateral movement of cassette mount 298 and its mounting rails. mount attachments 302a, b. A guide element 322 may be rigidly attached or mounted to the stationary frame 294 (or alternatively to the stationary members 296a,b), and extend in the desired direction of movement of the cassette mounting rails 302a,b. Guide element 322 may interface with cassette mount 298 (or alternatively flange 300a or 300b, or mount rail 302a or 302b), through a guide hole 324 (or guide rail, rail, or other element) that limits the relative movement of the cassette mount 298 back and forth with respect to the frame 294 or stationary members 296a,b. Figure 56 shows the cassette seating apparatus 292 in a nearly fully retracted position, with the cassette mount 298 retracted away from an associated receptacle mount enough to disengage the cassette actuation (or fluid) ports from an installed cassette. from their respective receptacle ports. (See, for example, Figures 30, 31). Figures 57 to 59 show the cassette seat apparatus 292 in a mating position, with the cassette mount extended linearly away from the stationary frame 294 or stationary members 296a, 296b far enough to mate the actuation ports (or liquid) from the cassette of an installed cassette with their corresponding receptacle ports. Actuating arms 306a,b of handle 308 are pivotally connected at a distal end 326 to stationary members 296a, 296b. Each actuator arm 306a,b is also pivotally connected at a proximal portion 328 of arm 306a,b to a first end of a connecting member 330a,b. A second end of the connecting member 330a,b is then pivotally connected to an actuating rod 332 having a pivotal connection to the second end of each rocker arm 310a,b comprising the cassette seating apparatus connection 292. The connecting member 330a or 330b moves eccentrically with respect to the axis of rotation of the actuator arm 306a or 306b, which allows movement of the actuator rod 332a,b and rocker arm 310a,b away from the stationary member 296a, 296b. Ln / nznz / E / Yi Optionally, a cassette mount retaining member 334 may be used to hold the cassette mount 298 in a retracted position. In one example, cassette mount retaining member 298 may comprise a ratchet, which is pushed to the side by crossmember 304 (or alternatively another element attached to cassette mount 298, flange 300, rail 302, or axle / pinion 318) when handle 308 is pulled fully to a retracted position (see figure 56). When the crossbar 304 reaches a recess in the pawl 336, it lowers to engage the crossbar 304 and holds the cassette mount 298 in its retracted position. In an additional or alternative embodiment, handle 308 may include a movable plunger element (replacing handle post 338 - see Figure 57, 59) that can engage or penetrate a hole or recess (not shown) in a front flange 340. of the stationary frame 294. Optionally, the plunger can be spring-loaded to automatically engage the front flange when a user releases the handle 308. As applied to hemodialysis enclosure 254 (see Figure 23), cassette seating apparatus 292 may be mounted to a ceiling within enclosure 254, as shown in Figures 45 and 46. This is in a position opposite to the receptacle assemblies 266, 268, 270 (in this case, manifold adapters). The cassette mount 226 can be seen installed in a cassette seating apparatus 292 via a cassette mount frame plate 513, for example, as shown in Figures 21 and 46. In Figures 30 and 31, the Cassette mount ports 240 are shown as being directly adjacent to corresponding receptacle ports on the receptacle mounts, and are fully disengaged from them when handle 308 is placed in a retracted position (FIG. 30). Pneumatic pump system using binary valves Figure 60 is a schematic view showing one embodiment of a pressure actuation system 14000 for a positive displacement diaphragm pump (capsule pump) 234, such as that shown in Figure 20. In this example, the Air pressure is used as the control fluid (for example, so that the pump is pneumatically driven). Other fluids (eg, water or water-based solutions) may also be used as control fluids in other modalities. In Figure 60, pressure actuation system 14000 alternately provides positive and negative gas pressure in actuation chamber 14020 of pod pump 23a. The 14000 Pneumatic Actuation System includes a 14020 actuation chamber pressure transducer, LP1 positive supply valve, NI negative supply valve, LPOS positive pressure gas source, NEG negative pressure gas source, a positive pressure source pressure transducer (not shown), a negative pressure source pressure transducer (not shown), as well as a controller Electronic Ln / nznz / E / Yi 14035. The electronic controller receives pressure data from the pressure sensor 14020 and controls the valves NI, LP1 to control the operation of the pump 23a. These two valves are controlled by a 14035 electronic controller. (Alternatively, a single 3-way valve can be used instead of the two separate LP1, NI valves.) In some cases, the positive supply valve LP1 and the negative supply valve NI are binary on-off valves that are either fully open or fully closed. The LPOS positive pressure source provides the 14020 actuation chamber with positively pressurized control gas to drive the 14025 diaphragm toward a position to minimize the 14027 pumping chamber volume (i.e., the position where the diaphragm is against the rigid wall of the pumping chamber). Negative pressure source NEG provides actuation chamber 14020 with negatively pressurized control gas to push diaphragm 14025 in the opposite direction, toward a position to maximize the volume of pumping chamber 14027 (i.e., the position where the diaphragm is against the rigid wall of the pumping chamber). The 14035 controller can also receive pressure information from three other pressure transducers: a 14020 actuation chamber pressure transducer, a transducer in LPOS, and a transducer in NEG. As their names suggest, these transducers respectively measure the pressure in the 14020 actuation chamber, the LPOS positive pressure source, and the NEG negative pressure source. The 14035 controller monitors the pressure in the two LPOS, NEG sources to ensure they are adequately pressurized (either positively or negatively). A compressor type pump or pumps can be used to maintain desired pressures in reservoirs comprising LPOS, NEG sources. In one embodiment, the pressure provided by the LPOS positive pressure reservoir is under normal conditions of sufficient magnitude to push the diaphragm 14025 all the way against the rigid wall of the pumping chamber. Similarly, the negative pressure (ie, vacuum) provided by the negative pressure source NEG is preferably of sufficient magnitude, under normal conditions, to urge the diaphragm all the way against the rigid wall of the actuation chamber. However, in preferred embodiments, the positive and negative pressures provided by the LPOS, NEG sources are kept within safe enough limits to avoid excessively high fluid pressures that could harm a patient to whom the pumping system may be attached. The 14035 controller monitors the pressure information from the 196 actuation chamber pressure transducer and, based on this information and possibly a timer, controls the valve mechanism (LP1, NI valves) to push the 14025 diaphragm to the minimum position. of volume from the pumping chamber, followed by a pressure switch to Ln / nznz / E / Yi pull the diaphragm 14025 to the maximum volume position of the pumping chamber. The pressure actuation system comprises a pressure distribution manifold, which can contain the 14020 actuation chamber pressure transducer, the transducer for the LPOS source, the transducer for the NEG source, the LP1 positive supply valve, the negative supply valve NI. The 14035 controller can be manifold mounted, and the LPOS positive pressure gas source and NEG negative pressure gas source can include conduits through the manifold. The manifold can be constructed to fit wholly or primarily in the hemodialysis housing recess 258 (see, for example, Figures 44, 48). In this arrangement, the components that come into contact with the blood or dialysate (i.e., capsule pump 23a, inlet valve 192, and outlet valve 193) can be located in an isolated enclosure 254 or a front panel 248 (see figure 23) so that the pump, valves and fluid interconnection pathways can be more easily accessed and / or disinfected. Pumping procedure with binary valves The procedure of pumping liquid through the capsule pump 23a can be better understood with reference to Figures 61 and 62. Referring now to Figure 61, the target pressure 14050 and the actual pressure 14055 measured by a pressure sensor 196 (FIG. 60) are plotted against time for a supply stroke and a fill stroke. A supply stroke involves the use of positive pressure from the LPOS source to drive the diaphragm 14025 from one side of the pump housing 23a to the other and expel the liquid in the pumping chamber 14027. In contrast, a fill stroke uses sub-atmospheric pressure from the NEG source to pull the diaphragm 14025 back through the capsule pump 23a and fill the capsule pump with liquid. In some examples, the fill stroke is completed by connecting the 14020 actuation chamber to atmosphere, allowing fluid pressure in the system to drive the diaphragm through the pod pump chamber. In a 14000 binary valve driven pump, the supply and fill pump strokes comprise multiple load cycles producing the irregular 14050 pressure trace of Figures 61 and 62. A detail of the start of a 14050 pressure trace is shown in Figure 62. supply stroke, in which during the movement of the liquid, the actual pressure 14055 rises when the valve LP1 is open and falls when the valve LP1 is closed. On the supply stroke, the movement of liquid from the pumping chamber 14027 decreases the volume of the pumping chamber; and because the total volume of the capsule pump is fixed, this increases the volume of the actuation chamber 14020. The increased volume of the actuation chamber results in a reduction in pressure in the actuation chamber if the pneumatic valve LP1 is closed. A charge cycle comprises the pressure rise resulting from an open valve and the pressure drop when the valve is closed. The duration of the charge cycle may vary as Ln / nznz / E / Yi is shown in figure 62, where 3 complete charging cycles are shown, each with a different duration. Figure 62 plots the details of a supply stroke, in which positive pressure is applied. Referring now to the fill stroke of Figure 61, the pressure trace 14055 has a similar irregular pattern. However, during the fill stroke, the pressure drops rapidly when the NI valve is open, exposing the actuation chamber to the NEG source, and recovers more slowly towards atmospheric pressure when the NI valve is closed. Once again, the charging cycle comprises a rapid increase in the magnitude of the actuation chamber pressure and a slower decrease in pressure toward atmospheric pressure when the NI valve is closed. Where in earlier applications and descriptions, continuously variable valves were used to control diaphragm pumps, binary valves are described here that are fully open or fully closed and not designed to be partially open. Binary valves and associated control electronics are generally less expensive than variable-opening valves. In addition, binary valves may require less functional controls / monitoring and may be less sensitive to the presence of debris in or away from the pneumatic lines leading to them. The inherent digital or on / off functionality of binary valves requires unique control algorithms for pressure control and detection of end of travel and flow path occlusions. The controller 14035 controls the NI and LP1 valves based on signals received from the pressure sensor or transducer 196 according to a series of algorithms that can be executed sequentially or simultaneously. These control algorithms are unique to binary valves due to their inherent digital or on / off functionality. Control algorithms include algorithms to control the flow of fluid through the pump, to control the pressure within the 14020 actuation chamber, to detect an end of travel condition (EOS), to detect a total occlusion of the line input, to detect complete occlusion of the output line, to detect partial occlusions, and to measure an access metric (an indication of the quality of blood flow obtained from a patient's venous or fistula access). The controller 14035 calculates information about the flow of liquid through the pump based on the pressure signal from the sensor 196 when the valves NI, LP1 are closed. The 14035 controller uses the received pressure data to monitor actuation chamber pressure, detect EOS, occlusions, partial occlusions, and determine access metrics. Pressure Control Description The flow rate through a pneumatically driven diaphragm pump, such as the pod pump 23a, is controlled by setting a target pressure for the actuation chamber 14020. The pod controller 14035 then controls the pressure in the actuation chamber. Ln / nznz / E / Yi 14020 actuation measured by a pressure sensor 196 fluidly connected to the 14020 actuation chamber which controls a NI valve, LP1, which fluidly connects a pressure source to the actuation chamber of the bomb. In an exemplary control algorithm, the controller averages the pressure data from the pressure sensor 196 while the binary valve NI, LP1 is closed and opens the valve NI, LP1 when the accumulated averaged pressure approaches or equals the target pressure. . In one example, the 14035 controller closes the NI valve, LP1 when the magnitude of the pressure data equals or exceeds the target pressure. In one example, the 14035 controller closes the NI valve, LP1 when the magnitude of the pressure data equals or exceeds the target pressure minus a predetermined constant value. In another example, the default value, instead of being constant, varies with the direction of the race and the duration or stage of the race. In another example, the 14035 controller integrates the difference between the measured pressure magnitude and the target pressure and opens the NI LP1 valve when an integrated difference approaches or equals zero. The flow of fluid through the pump is controlled by the amount of negative pressure applied to the actuation chamber to fill the pumping chamber with liquid and the amount of positive pressure applied to the actuation chamber to supply fluid from the pump. pumping chamber. In some examples, the pod pump controller 14035 is programmed to receive or calculate a desired flow rate and / or maximum volume displaced from the pod pump 23a. The 14035 controller can set initial target pressures for fill and dispense strokes. The controller controls the pressure in the actuation chamber to reach or approach a target pressure. The controller monitors the time to complete a stroke and determines the actual flow rate by dividing the volume displaced by the time to complete the stroke. The 14035 controller can change the target pressure based on a difference between the most recent actual flow rate and the desired flow rate. For example, the 14035 controller can increase the target pressure if the actual measured flow rate was below the target flow rate. In another example, the controller may decrease the target pressure if the actual measured flow rate is above the desired flow rate. The 14035 controller can change the dispense stroke independently of the fill stroke. In one example, the 14035 controller can use a feedback loop that modifies the target delivery pressure based on measured flow rate during delivery strokes to achieve a desired flow rate. In another example, the feedback loop modifies the target negative fill pressure to be based on the flow rate measured during the fill strokes in order to achieve the desired fill rate. In previous descriptions, a chamber connected by a binary valve to a pressure source has been controlled based on limits on the target pressure. The controller would connect the pressure source to the chamber by opening a valve between them when the magnitude of the Ln / nznz / E / Yi measured pressure in the chamber was a predetermined amount below the target pressure magnitude. The controller would then close the valve when the magnitude of the pressure measured in the chamber was one second predetermined value above the magnitude of the target pressure. In some cases, applying this limit approach to air operated diaphragm pumps produces an average chamber pressure magnitude that is less than the target pressure magnitude. In some cases, the opening of the valve produced a very rapid increase in the magnitude of the pressure in the chamber, whereas the drop in the magnitude of the pressure due to liquid entering or leaving the pumping chamber was much slower. . This mismatch in the rate of pressure changes shifts the magnitude of the time-averaged pressure below the magnitude of the target pressure. In cases where the flow of liquid into or out of the pump varies with time, the offset between the average pressure and the target pressure can also change over time, making it difficult to continually correct the offset in rate. of pressure changes. The pressure in the actuation chamber can be controlled by comparing the measured pressure with a target pressure. The controller opens and closes a pneumatic valve that connects the actuation chamber to a pressure source or reservoir. The controller can open and close the LP1 valve during the supply stroke to maintain the pressure in the 14030 actuation chamber close to the 14052 supply target pressure. The 14035 controller opens and closes the NI valve during the fill stroke to maintain the pressure in the actuation chamber 14030 near the target fill pressure 14054. In one example, the controller closes the air valve when the magnitude of the measured pressure exceeds the target pressure, and reopens the air valve when the average measured pressure in the actuation chamber approaches or equals the target pressure. In the algorithm shown in Figures 63 and 64, referring to Figure 62 and described below, controller 14035 controls valves NI, LP1 to maintain the average pressure in actuation chamber 14020 at target pressure while maintaining average pressure. in the actuation chamber at the target pressure while the NI, LP1 valves are closed. Referring now to the pressure control algorithm 14100 in Figure 63 and referring to Figure 60, a pump controller (which may be independent or different from controller 14035 in Figure 60) selects the direction of stroke 14105 and the pressure Target, Fill, and PTF (Pressure-Target-Fill) or Supply and PTD (Pressure-Target-Supply). If a fill stroke is selected, then at 14110 controller 14035 opens the valve that fluidly connects the NEG source or reservoir to actuation chamber 14020, and monitors pressure sensor 196 at 14120. At each time step on the 14130 Block, the controller evaluates if the magnitude of the pressure is greater than the magnitude of the target pressure, and if not, leaves the valve Ln / nznz / E / Yi open. At block 14140, once the magnitude of the measured pressure is equal to or greater than the target pressure, the NI valve closes. At block 14150, the difference between the measured pressure P and the target pressure TTF is added at each time step. At block 14160, the limit switch function or algorithm checks for a limit switch and directs the controller logic to the limit switch 14200 if the EOS criteria are met. Note that the logic in block 14160 can be placed anywhere in the flowchart between 14140 and 14180, or it can be a separate function of the 14100 pressure control algorithm. In block 14170, the summed pressure difference is compared with zero. If the summed pressure difference is greater than zero, the controller logic returns to 14150 for an additional time step. In the case where the sum of the pressure differences is equal to or less than zero, the controller logic resets the sum of the pressure difference in block 14180 and returns the logic to block 14110 where the valve opens. NEITHER. A single controller can coordinate the timing of pump strokes, setting of target pressures, and operation of pneumatic control valves. Alternatively, the tasks can be divided between two or more controllers, for example, with a main controller determining the timing of pump strokes and target pressures, and a sub-controller controlling the pneumatic control valves. Referring to Figures 63 and 60, if a main controller selects a delivery stroke, it also defines a target pressure and the subcontroller moves the logic to block 14210 (Figure 63) where valve LP1 opens. In a series of steps similar to the fill procedure, the pressure in the 14020 actuation chamber is monitored by the 196 pressure sensor in the 14220 block. The 14230 block evaluates the pressure against the target pressure and whether the measured pressure equals or greater than the target pressure, directs the logic to block 14240 where valve LP1 is closed. Referring now to Figure 60, the chamber pressure 14055 continues to rise after valve LP1 is commanded to close at 14051, where the chamber pressure exceeds the target pressure. Chamber pressure 14055 can increase to 14052 due to delayed valve closure and due to fluid / thermal dynamics that can affect chamber pressure. Referring to Fig. 63, at block 14250, the difference between the chamber pressure P and the target pressure PTD is summed for each time step. The sum of this difference between chamber pressure P and target pressure PTD from point 14052 until chamber pressure 14055 equals target pressure 14050 is area 14080 in Figure 62. Area 14085 is the sum of the difference between the chamber pressure and the target pressure when the magnitude of the chamber pressure 14055 is less than the magnitude of the target pressure 14050. Referring again to Fig. 63, at block 14260 executes the EOS algorithm and the race ends at 14200 if an EOS is detected. Ln / nznz / E / Yi At block 14270, the sum of the pressure difference from block 14250 is evaluated. Block 14270 directs the logic to 14210 where valve LP1 is reopened, if the sum of the pressure differences is less than or equal to zero. The sum of the pressure difference is set to zero in block 14280 before the logic reaches block 14210, at which point LP1 opens. Alternatively, the sum of the pressure difference can be reset to zero any time in the logic after block 14270 and before block 14240. Referring now to Fig. 62, the block 14270 criterion can be represented graphically as the case where the area of ​​14080 equals the area of ​​14085. The block 14270 criterion is met when the sum of the actual pressure is 14055 minus the 14050 target pressure (for actual pressures greater than the target pressure) is equal to the sum of the 14050 target pressure minus the 14055 chamber pressure (for chamber pressures less than the target pressure). Alternatively, the 14270 criterion is met when the sum of [average pressure magnitude minus target pressure magnitude] is equal to or less than zero. In one example, blocks 14130 and 14230, the chamber pressure P is compared to predetermined pressures PD, PF that are different by a pressure offset from the target pressures PTD, PTF. In some examples, to limit pressure overshoot, the magnitudes of PD, PF are a predetermined value less than the magnitude of the target pressures PTD, PTF. Referring now to Fig. 62, if the PD is less than the target pressure (14050D), then the signal to valve LP1 in Fig. 60 will be sent earlier and the maximum pressure at 14052 will be less. In one example, the magnitude of the pressure displacement is different for the fill stroke and the supply stroke because the mean pressures for the fill stroke and the supply stroke are different. Since the valve actuation delay is a fixed value and the pressure overshoot is inversely proportional to the volume of the actuation chamber (which changes during the stroke), the overshoot can also vary, as can be seen in figure 61. In general, the overshoot is greatest at the beginning of the supply stroke 14060 and at the end of the fill stroke 14075 when the volume of the actuation chamber 14020 has the smallest volume. The displacement of the fill and supply races may vary during the race. In one example, the magnitude of the displacement is greatest at the beginning of the supply stroke and is reduced with each charge cycle until the displacement reaches a minimum value. In the same or another example, the amount of displacement is smallest at the beginning of the fill stroke and increases with each load cycle until the displacement reaches a maximum value. Displacement values ​​may vary with time, number of load cycles, valve openings, or added differential pressures when valves are closed during pumping. Ln / nznz / E / YiAi race. Another example of the 14300 pressure control algorithm is presented in Figure 64. The 14300 algorithm is similar to the 14100 algorithm except for elements 14350, 14370, 14380, 14450, 14470, and 14480, where the average pressure replaces the difference between the measured pressure and the target pressure. In blocks 14350 and 14450, the measurements from the pressure sensor 196 are averaged while the valves NI, LP1 are closed. In block 14370 and 14470, if the average pressure, PAVG equals the target pressure within a predetermined range, the logic proceeds to blocks 1410, 14210 respectively to open valve NI, LP1 after zeroing the average pressure . End of run detection Accurate or reliable determination of flow rates and volumes of flow through a pump 23a as shown in Figure 60 depends on an accurate or reliable algorithm for determining end of travel (EOS). The limit switch occurs when the 14025 diaphragm has moved through the pump body cavity and has reached one of the pump body walls. The controller 14035 detects the condition of the chamber against the wall by observing that the magnitude of the chamber pressure, measured by the pressure sensor 196, does not drop when the valve NI, LP1 is closed. The chamber pressure does not drop because the diaphragm 14025 is against the chamber wall and cannot move and therefore cannot change the volume of the actuation chamber 14020. The EOS detection algorithm detects an end of travel condition based on valve conditions, chamber pressure, and chamber pressure rate of change. The algorithm detects an EOS condition for a pneumatically driven diaphragm pump, where the pneumatic pressure is controlled by a pneumatic valve that connects the pump to a pressure reservoir, a pressure sensor that measures the pneumatic pressure applied to the pump, and a controller in communication with the pump and pneumatic valve. In one example, EOS detection is based on the number of load cycles executed by the pneumatic valve and the rate of change in pressure while the pneumatic valve is closed. In another example, the EOS is declared when a predetermined number of charge cycles have occurred and the rate of change of pressure magnitude is less than a predetermined rate. In another example, EOS detection is declared when a predetermined number of charge cycles have occurred, the pressure is within a predetermined range, and the rate of change of pressure magnitude is less than a predetermined rate. Referring now to Figure 60, controller 14035 changes the direction of the stroke from dispense to fill or from fill to dispense after sensing an end of travel (EOS). The limit switch algorithm is schematically described in figure 65 and can be understood with Ln / nznz / E / Yi refer to Figure 61. The EOS algorithm 14300 is executed as part of the pressure control algorithm 14100, in blocks 14160 and 14260, or the EOS algorithm may be executed in parallel. Block 14310 monitors the pressure in the actuation chamber as detected by pressure sensor 196 (FIG. 60). At block 14320, the number of charge cycles that have occurred during the current stroke is compared to a predetermined number. If more than the predetermined number of charge cycles have occurred, then block 14330 compares the minimum rate of change of pressure magnitude (dP / dt) with a predetermined rate (dPEOS). If the minimum rate of change is less than the predetermined rate, then at block 14340 the difference between the current pressure P and the target pressure PT is evaluated. If the difference is less than a predetermined difference DP, an EOS is declared and the controller changes the pump strokes, the target pressure, and changes the state of the hydraulic valves 192, 193 (valves that in the currently described dialysis system may be diaphragm valves which may also be actuated by pressures supplied by the manifold and controlled by the controller). If the difference between the chamber pressure and the target pressure is greater than the default difference, then the 14035 controller declares an occlusion. Still referring to Figure 65, at block 14330, dP / dt is the minimum rate of change of the pressure magnitude in the actuation chamber. In some examples, the minimum rate of change is only determined while the pneumatic valves, NI, LP1 are closed. In some examples, the minimum rate of change of the pressure magnitude is derived from low-pass filtering of the pressure values. In another example, the rate of change of pressure magnitude is itself low-pass filtered before being compared to the predetermined rate of change of pressure (dPEOS). occlusion detection Referring now to Figure 60, controller 14035 can be configured to detect occlusions in the flow to and from pump 23a. The user interface can signal an alert or alarm that an input or output line is occluded. In one example, a user may be instructed to inspect bloodlines 203 and 204 for kinks, pinches, or other obstructive elements. An occlusion detection algorithm can be considered a safety feature that prevents thrombosis in the blood circuit or can identify a problem with fluid flow in water or dialysate circuits. Occlusions in the pump inlet and outlet lines are detected by the 14035 controller based on information received from the 196 pressure sensor, while the 14020 actuation chamber is isolated from the NEG, LPOS pressure reservoirs. The pressure sensor 196 measures the pressure in the actuation chamber. The 14035 controller detects input line occlusions during fill strokes and output line occlusions during fill strokes. Ln / nznz / E / Yi racing supply. The 14035 controller adds the pressure change that occurs in the actuation chamber while the NI, LP1 valve is closed. The 14035 controller determines the presence of an occlusion by comparing the sum of the pressure changes across all charge cycles during a single pump stroke to the sums of the pressure difference during previous strokes and a predetermined value. The 14035 controller can also base the detection of an occlusion on the number of load cycles completed before an end of travel is detected and / or the difference between the actuation chamber pressure and the target pressure. Referring now to Figure 66, where the occlusion algorithm 14400 is presented as a flowchart beginning at step 14410 in which a fill stroke or delivery stroke is initiated by setting a target pressure and then opening a valve NI, LP1 (FIG. 60) in step 14415. Valve NI, LP1 is closed in step 14420. In step 14425, the controller adds the pressure change (dPSUMA) while the pneumatic valves NI, LP1 are closed. The sum of pressure changes (dPSUMA) is added over the entire stroke, which includes multiple 14427 load cycles. In one example, the 14035 controller determines the pressure change from the time step before the time step current: Pi-1 - Pi and adds this pressure change to the current sum of the pressure changes for each time step that the pneumatic valve NI, LP1 is closed. In one example, the controller determines the pressure change between the time valve NI, LP1 closes and then reopens, and then adds this pressure change to the pressure change sum (dPSUM) that includes all the pressure changes. pressure changes since the run began at step 14410. Continuing with reference to FIG. 66, the occlusion algorithm 14400 checks for an end of run condition in step 14430 after updating the pressure change sum (dPSUM) in step 14425. If an EOS is not detected, then the 14035 controller at step 14435 checks if the charge cycle is complete and it is time to reopen the valve. The end of charge cycle step 14435 can be performed based on one or more parameters, including (but not limited to) current pressure, average pressure during the current charge cycle, or pressure difference integration between the target pressure and the chamber pressure during the current charge cycle. If step 14435 determines that the charge cycle is not complete, then the sum of the pressure changes is updated for the next time step in step 14435. If the charge cycle is complete, then the NI pneumatic valve, LP1 it is reopened in step 14415. When a limit switch is determined in step 14430, the occlusion algorithm 14400 proceeds to multiple independent occlusion tests in steps 14440, 14450, 14455, 14460. Step 14440 directs the logic for low sensitivity to step 14450 and high sensitivity. to step 14445. In one example, step 14440 selects low sensitivity for short strokes or Ln / nznz / E / Yi blood pump partials due to short stroke variability in the blood pump. On short strokes, the diaphragm is not driven against the inside wall of the capsule pump. Instead, the supply run is shortened. In some medical applications, the short delivery stroke may be beneficial in reducing damage to blood cells between the diaphragm 14025 and the walls of the capsule pump 23a. Short runs have more variability; and to avoid false occlusion detections, the low sensitivity occlusion test may be preferred in step 14450. In one example, step 14440 directs the logic to step 14445 for all non-short stroke operations. Continuing with reference to Figure 66 where the occlusion algorithm 14400, at step 14445, compares the sum of the pressure differences for the just completed stroke (dPSUMA) with the sum of the pressure difference for the last good stroke in the same direction (dPGOOD). In one example, an occlusion is detected when two consecutive runs in the same direction have a dPSUMA less than 30% of the last good run (dPsum). More generally, an occlusion is detected when a run has a dPSUMA that is less than a predetermined fraction of the last good run (dPsum). In one example, an occlusion is detected when more than two runs have a dPSUMA that is less than a predetermined fraction of the last good run (dPsum). If an occlusion is detected, the logic moves to step 14470 where an occlusion alert or alarm is sent to the user interface (UI) and, in one example, the pump may be stopped. In some modes, the UI indicates which pump and where the input or output line is occluded. If an occlusion is not detected at 14445, the logic moves to step 14455. Figure 66 depicts the 14400 occlusion algorithm including, at low sensitivity step 14450, a comparison of the sum of the pressure differences for the just completed stroke (dPSUMA) with the sum of the pressure difference for the last stroke. good in the same direction (dPGOOD). In one example, an occlusion is detected when three consecutive runs in the same direction have a dPSUMA less than 10% of the last good run (dPsum). In one example, an occlusion is detected when a run has a dPSUMA that is less than a predetermined fraction second of the last good run (dPsum). Alternatively, an occlusion is detected when more than three runs have a dPSUMA that is less than a predetermined fraction of the last good run (dPsum). If an occlusion is detected, the logic moves to step 14470 where an occlusion alert or alarm is sent to the user interface (UI) and, in one example, stops the pump. In one embodiment, the user UI indicates which pump and where the inlet or outlet line is occluded. If an occlusion is not detected at 14450, the logic moves to step 14455. At step 14455, controller 14035 detects an occlusion if in one or more Ln / nznz / E / Yi consecutive strokes in the same direction one of the following conditions occurs: less than a predetermined number of load cycles occurs, or the sum of pressure changes (dPsum) is less than a predetermined limit (dPsumLimit ). In one example, an occlusion is detected if either condition occurs on 3 consecutive runs in the same direction. In another example, an occlusion occurs if either condition occurs in 2 consecutive cycles. In another example, the default number of charge cycles is 5. In another example, the default number of charge cycles is half the number of charge cycles in a typical stroke. If an occlusion is detected, the logic moves to step 14470 where an occlusion alert or alarm is sent to the user interface (UI). In an exemplary response, the bomb stops. The controller can send data to the user UI to indicate which pump is affected and if the occlusion occurred on the input or output line. If an occlusion is not detected at 14455, the logic moves to step 14460. At step 14460, controller 14035 detects an occlusion if the magnitude of the pressure in actuation chamber 14020 is significantly greater than the target pressure for a predetermined period of time. In one example, step 14460 detects an occlusion if the magnitude of the pressure in the actuation chamber 14040 is greater than the magnitude of the target pressure by more than 60 mmHg for a predetermined period of time. In another example, the default time period in step 14460 is 25% of the stroke duration, the stroke duration being the time from the start of the stroke to EOS detection. Partial occlusion detection Partial occlusions can limit flow, but not block flow in liquid lines. The functions of the hemodialysis machine can be changed and / or the messages to the user can be changed depending on whether a partial occlusion or a total occlusion is detected. The controller detects a partial occlusion based on the flow rate from a recent stroke and the target stroke pressure from that recent stroke. The pump controller varies the target pressure to achieve a desired flow rate and increases the target pressure for the next stroke if the flow rate for the last stroke was below the desired flow rate. There are maximum target pressures for a given pump, where the maximum pressure may be a function of pressure reservoir pressure and / or the usage of the given pump. In one example, a partial occlusion may be declared if the recent flow rate through the pump does not reach the desired flow rate despite setting the target pressure for that recent stroke to the maximum value. In another example, a partial occlusion may be declared when the flow rate for a recent stroke is less than 75% of the desired flow rate despite the target pressure for the recent stroke being set to the maximum value. In a hemodialysis system, the partial occlusion detection function can be applied to pumps Ln / nznz / E / Yi blood to determine if there is a problem with an individual's vascular access or with the position of a set of blood lines. Blood flow metrics In one embodiment, the controller can be programmed to provide the user of an extracorporeal or hemodialysis system with an indication of blood flow metrics (the quality or velocity of blood flow from a venous access or arteriovenous fistula) during the course of each stroke. bomb filling. For example, a flow metric value can be transmitted to a graphical user interface, providing the user with a continuous indication of the quality or adequacy of blood flow in the bloodline during therapy. A user interface (such as, for example, an electronic tablet) can provide the user with raw flow metric data. In another embodiment, the flow metric can be scaled proportionally to a range from 1 to 5, where the value '5' represents, for example, excellent flow, a value '3' represents marginal flow, and a value '1' represents occluded flow. . Therefore, a specific range of flow metric values ​​can be assigned to each of a set value of '1' to '5', which simplifies the user's interpretation of blood flow adequacy in the bloodline. In other embodiments, the flow metric may be displayed to the user graphically, such as a moving or expanding bar graph, a dial indicator, or a set of colored lights, for example. In a preferred embodiment, a marginal or suboptimal flow metric may cause the controller to alert the user so that the user can attempt to improve blood flow in the bloodline (eg, reposition the line, straighten the line, adjust the line). vascular access cannula, etc.). The controller can be programmed to initiate a procedure to pause or stop the dialysate pump including signaling the user and providing sufficient time before pausing or stopping a dialysate pump to allow the user to correct the condition. The user can be alerted to the low flow condition during a fill run so that timely adjustment by the user allows the flow metric to be restored to an acceptable value before the end of the fill run. Alternatively, the controller can be programmed to allow sub-optimal flow metrics for two or three (or more) consecutive fill runs before commanding the dialysate pump to stop. Therefore, timely correction of the low flow condition by the user can prevent interruption of dialysate pumping operations and possibly interruption of therapy. In one example, the controller can be programmed to pause or stop the dialysate pump if the flow metric remains below 150 (for example, as dP / dt in mm Hg / sec) for three consecutive fill strokes, and can be programmed to not restart the dialysate pump until the flow metric exceeds 200 for five consecutive runs of Ln / nznz / E / Yi the blood pump. In some of these modes, the controller allows the blood pump to continue to run while the dialysate pump has been suspended, giving the user an opportunity to restore a blood flow condition that allows the dialysate pump to restart, avoiding thus early termination of therapy. Referring now to Figures 60 and 62, the controller 14035 can determine the flow metric during a fill stroke based on the actuation chamber pressure while the NI pneumatic valve is closed. The actuation chamber pressure is measured by the pressure sensor 196 that is in communication with the 14035 controller. In one example, the 14035 controller can determine the flow metric based on the rate of change of the pressure sensor signal. 196 while the NI valve is closed. In another example, the 14035 controller can determine the flow metric based on the minimum rate of change of actuation pressure during the stroke while the NI valve is closed (i.e., the lowest or near-lowest rate of pressure change detected). by the controller). In another example, the 14035 controller can determine the flow metric based on the minimum rate of change of the actuation pressure during the stroke, excluding the charge cycle that produced an end of stroke signal. In one example, the rate of change in actuation pressure is determined during each load cycle using a low-pass filter and the minimum values ​​of the rate of change for each load cycle are low-pass filtered over one stroke to determine the flow metric. Figure 67 illustrates the 14500 flow metric algorithm as a flowchart beginning with starting a fill stroke with a blood pump (23a in Figure 60). The upstream valve 192 opens and the downstream valve 193 closes. The fill stroke continues by opening the NI pneumatic valve at step 14515 and closing the NI valve at step 14520 to create a desired negative or lower ambient pressure in the actuation chamber 14020 of the blood pump 23a. The negative pressure in the actuation chamber 14020 draws blood from the access site through the tubing 203 to the pumping chamber of the blood pump 23a. The magnitude of the negative pressure in the 14020 actuation chamber decreases as the fill pump chamber expands and compresses the gas in the 14020 actuation chamber. This reduction in the magnitude of the negative pressure is detected by the sensor pressure switch 196 and communicated to controller 14035 at step 14525 (FIG. 67). The controller analyzes the data and (optionally) using a Low Pass Filter (LPF) function determines the rate of change of pressure (dP / dt) in the actuation chamber at step 14530. If end of cycle has occurred load, step 14535 directs the logic to step 14540 where the end of travel (EOS) is determined. If the end of the charge cycle has not occurred, then the logic goes to 14525 where the pressure signal continues to be monitored. If an EOS is not detected at step 14540, then the controller determines, at step 14545, the smallest magnitude of dP / dt while the NI valve is closed. The current duty cycle minimum or lowest dP / dt detected by the controller is then used in the LPF to update the minimum dP / dt for the fill stroke in step 14550 and then the NI valve reopens to start. the next charge cycle in step 14515. If an EOS is detected at step 14540, then the logic flows to step 14555, where the modulo controller 14035 reports the minimum dP / dt to a controller which converts the minimum dP / dt value into an easier to understand flag. displayed on the user interface (UI). The UI can be a graphical display unit, such as a tablet. The indicator is the flow metric of the blood input line and the access. In one example, the minimum values ​​of dP / dt are shown as a value from 1 to 5, where 1 is an occluded access, 3 is a marginal access, and 5 is a free-flowing access. Here, access means the needle or cannula system, needle or cannula placement, and flow restrictions at the entrance to the needle or cannula. In an example, the flow metric is 1 or occluded for a minimum dP / dt less than 25 mmHg / s, the flow metric is 2 or poor for a minimum dP / dt between 25 and 50 mmHg / s, the metric The flow metric is 3 or marginal for a minimum dP / dt between 50 and 75 mmHg / s, the flow metric is 4 or good for a minimum dP / dt between 75 and 100 mmHg / s, and the flow metric is 5 or excellent for a minimum dP / dt between 100 and 125 mmHg / s. In addition to displaying the flow metric in the UI in step 14555, the flow metric algorithm 14500 in step 14560 evaluates the flow metric and issues an alert to the user 14570 if the flow metric remains below a predetermined value. for more than a predetermined number of runs or time period. In one example, step 14560 indicates an alert at step 14570 if three consecutive fill strokes have a dP / dt below a value of 50 mmHg / s. In this case, the logic moves to a blood pump delivery stroke in step 14580 regardless of the flow metric or minimum dP / dt and then back to start a fill stroke in step 14510. Interface with water purification device The hemodialysis (HDD) device or apparatus can be configured to interface and communicate with a Water Purification Device (WPD) that provides water to the HDD system to mix the dialysate solution and to disinfect the HDD before or after a treatment. dialysis. In earlier disclosures (see, for example, U.S. Patent Application Publication No. US / 2016 / 0058933), a series of messages and data could be exchanged between HDD controllers and a WPD controller. In a more simplified approach, the types of interactions between the two devices can be limited, rather than relying on pre-programmed or stand-alone functions of the WPD. In one example, the WPD may be a steam compression / distillation apparatus. Alternatively or additionally, other water purification devices and methods may be used, such as semi-permeable membrane filtration, hR^n Ln / nznz / E / Yi reverse osmosis, ultraviolet irradiation, carbon adsorption, or any combination of these. An HDD controller can be configured to send a start signal to the WPD, which represents a command to start normal temperature water production, with the WPD proceeding according to its independently programmed processor. This is the mode that is normally used when pure water is to be supplied to the HDD for mixing and dialysate therapy. The HDD controller can also send a hot water start command to the WPD, which represents a command to start hot water production according to the pre-programmed procedures of the WPD. This is the mode that is normally used to perform a disinfection procedure for the WPD. The line connecting the WPD to the HDD (the HDD water inlet line) and the HDD itself can be sanitized by scheduled operations on one or more HDD controllers. The HDD controller may also command the WPD to enter a standby mode or state, or an idle mode or state. In a steam compression / distillation apparatus, an idle state may involve pausing pumps or compressors, turning off heaters, closing valves, and disabling control loops and water level controllers. A standby mode or state allows the WPD to produce purified water relatively quickly; and optionally in a steam / distillation system, this may include filling the purification system with water and heating it to a point where purified water production can begin, controlling a vent valve to maintain a target steam temperature of low pressure, as well as optionally producing enough water to fill a reservoir or, alternatively, sending the excess water it produces to the drain. If the WPD is starting from an idle state (power off) or a sleep state, the HDD controller can optionally be programmed to send the command early enough to allow the WPD to be producing water by the time the HDD expects to receive the command. water supply. (In some cases, this can be about 2 hours from a cold boot or sleep mode, or as little as about 10 minutes from a standby mode.) In most cases, the HDD controller will command an idle WPD into standby mode when the two systems establish communications, or when one or both systems restart after being powered off. This may not happen if an error condition has been checked. During water supply, the HDD controller may send a stop signal to the WPD, which commands the WPD to enter a standby state. In this case, the standby state is an autonomous function of the WPD that keeps the water production or purification active enough to be able to supply water by HDD command in a relatively short period of time (for example, within about 10 minutes from a boot or resume command that sends the HDD to the WPD). Among other operations, this may include filling hR^n Ln / nznz / E / Yi Ln / nznz / E / Yi the purification system with water and heat it to a point where the production of purified water can begin quickly. The HDD controller can also send a disinfection start command to the WPD, which is typically scheduled to occur after a dialysis therapy has been completed or during a time between HDD therapy sessions. In this case, the WPD enters an automatic hot water production mode. In a typical sequence, the HDD first commands the WPD to a water production mode, followed by a command to a sanitization mode once the WPD indicates that it has entered water production mode. Once the water produced by the WPD reaches a specified temperature (for example, 90 degrees C), the HDD controller receives a signal and the HDD initiates an inlet line disinfection procedure. The input line includes a flow path into the HDD before a branch point connects it to a flow path to the drain or mixing circuit of the HDD. (Beyond this branch point, the internal flow paths of the HDD can be sanitized by scheduled circulation of hot water or chemical sanitizer without any blind ends.) This state also sanitizes any tube connecting a WPD output port or line to an HDD input port or line. An HDD controller can be programmed to sanitize the WPD-HDD connection line and flow path at a predetermined minimum temperature for a predetermined minimum period of time. For example, the disinfection temperature can be set to 85 degrees C for a minimum time of 35 minutes. The temperature can be measured with a temperature sensor located in the HDD water inlet line. To reduce the number of temperature sensors in the HDD system, the inlet water temperature sensor can preferably also be located at a position in the HDD flow paths that can monitor the temperature of the disinfection fluid circulating through the HDDs. HDD flow paths during HDD system disinfection. Depending on the distance the incoming water travels before reaching the temperature sensor, the minimum disinfection temperature can optionally be adjusted to account for heat loss before the water reaches the sensor. Figure 68 shows a schematic illustration of a fluid flow path for a hemodialysis system described in previous applications. Section A represents a system blood flow path, section B represents a dialysate fluid equilibrium section and a dialyser supply section, section C represents a dialysate storage, heating and ultrafiltration section, and section D represents a water inlet and dialysate mixing section. The water inlet line 400 is configured to connect externally to a water source. In the current modality, the water source Ln / nznz / E / Yi comprises a water purification device (WPD), such as a water vapor compression / distillation apparatus. For ease of reference, inlet water line 400 is here understood to represent the complete water line connection between the purified water outlet of a WPD and the point 402 where the HDD inlet water line has a valved connection to the internal flow paths of the HDD. In reality, this inter-device water line may comprise one or more connectors or valves. But for disinfection purposes, the inlet water line 400 can be considered to include the entire water line between devices. Although the internal fluid flow paths of the WPD and HDD illustrated can be configured to achieve a complete and thorough sanitization procedure, sanitization of the water inlet line and / or interdevice line connecting the WPD to the HDD may require special attention. Note that the 400 water inlet line has a 402 valved connection to the internal flow paths of the HDD, and that this fluid connection between devices (WPD outlet line and HDD inlet line) becomes a blind end for complete disinfection purposes, either chemical or thermal. This condition is also reflected in the starting line of the WPD. Although the HDD dialysate heater can be used to heat water which can then be pumped by one or more dialysate pumps in the reverse direction through the HDD inlet line, through the WPD outlet line, and out of there to a drain connection of the WPD, it may be more efficient for purified hot water (or water containing an appropriate chemical sanitizer) to be produced by the WPD and delivered to the HDD in the normal direction of advance, and the sanitizing liquid is it will then discharge to a drain line 404 of the HDD. Fig. 69 shows an isolated view of portion D of the flow path section of the HDD system. Although a temperature sensor could be located on the 400 line, it would only serve to monitor the temperature of the incoming water. For disinfection purposes, incoming hot water could be directed directly to drain 404, but this flow path would be dependent on the action of a water pump located in the WPD. On the other hand, a temperature sensor 406 can be located in an internal line 408 connected to the water pump 410, which can then provide the necessary pumping action to move the water through the line 400 and 408. This sensor also It can be used to monitor liquid temperature during disinfection of various internal flow paths in the HDD system. The heated liquid from section C in Figure 68 can be directed to the flow paths in section D via the water line 408. The inlet line disinfection flow path incorporating the water pump 410 in the system illustrated in Figure 69 (see also Figure 68) it can be routed through the conductivity / temperature sensors 412, 414 in the dialysate mixing path, and from there make a bypass of the dialysate tank 416 closing valve 418 and Ln / nznz / E / Yi by opening valve 420, which leads to drain line 404. Note that, in an alternative embodiment, monitoring of the temperature of the sanitizing liquid can also be performed using existing temperature sensors already installed in order to mix the dialysate (i.e. sensors 412 or sensors 414), without adding a temperature sensor in the inlet water line 400 or 408. In all of these cases, actively managed valves or passive check valves ensure that the sanitizing liquid is directed to the 404 drain line. In one embodiment, and as shown in Figure 70, initiation of a sanitization procedure may involve first having the HDD 450 command the WPD to begin normal water production. After this, the HDD starts 452 priming its flow paths with water from the WPD. The HDD then commands 454 from the WPD to produce heated water at the required disinfection temperature. Optionally, the temperature at which the WPD produces hot water is higher than the minimum disinfection temperature specified for the line interconnecting the WPD and the HDD. This is to account for heat losses from the water as it travels through the interconnection line. For example, if the minimum disinfection temperature is 85 degrees C, then the WPD can be programmed to produce 90 degrees C water at its outlet. Optionally, the HDD can be programmed to start 456 its own production of hot water using its internal heater (for example, the heater 411 shown in Figure 68). This prepares the HDD to perform its own sanitization after the interdevice line 400 has been sanitized, and helps maintain a high ambient temperature in the HDD housing to limit heat losses during the interdevice line 400 sanitization. Once both the HDD and WPD have heated their respective fluid flow paths to specified temperatures, the HDD controller can then command the WPD to begin supplying 458 hot water from its product outlet line to the line between devices (input line 400) that connects the WPD to the HDD. The disinfection temperature of the water may vary during the disinfection period. Optionally, an HDD controller can be programmed to track the amount of time the measured temperature reaches or exceeds the minimum disinfection temperature programmed into the controller. As shown in Figure 71, optionally prior to starting a sanitization timer for the inter-device line 400, the HDD controller begins to control an internal HDD pump and associated valves to circulate 460 incoming hot water from the WPD for a period of time. predetermined amount of time to completely fill the disinfection flow path with hot water. In addition to the line between devices, in one example, this flow path may include the flow path within the HDD that directs sanitizing water through the water pump 410 in the mixing circuit, through a line that leads to dialysate tank 416 but is diverted to drain 404 by one or more valves 418, 420. (See, for example, Figure 69). In one example, the HDD controller directs hot water from the WPD to the HDD drain for approximately 2 minutes before the inter-device line sanitization timer starts. The HDD controller can be programmed to include a default minimum sanitization temperature (for example, 78 degrees C). Once this temperature is detected by a temperature sensor (for example, sensor 406 or sensor 412 or 414), the controller starts a sanitization timer 462. If this minimum sanitization temperature is maintained 464 for a minimum time of sanitization (for example, 35 minutes), then the controller can declare that the sanitization of the line between devices 400 is complete. The disinfection timer is updated 464 whenever the detected temperature is equal to or higher than the minimum disinfection temperature. Optionally, the controller can be programmed to include a timer 466 that accumulates an amount of time in which the sensed temperature is less than the minimum disinfection temperature but greater than or equal to a predetermined low temperature threshold value (for example, 70 degrees C ). If a predetermined low temperature timeout value is reached (for example, 10 minutes for the sanitization cycle to time out), then the controller can signal an alarm to the user interface and command the WPD to suspend production of 468. Optionally, the controller can also be programmed to signal an alarm and command the WPD to suspend production of water 468 if the sensed temperature is less than a predetermined low temperature threshold value (eg, 70 degrees C). If the inter-device line sanitization 400 is successful 470, then the HDD controller can close the inlet water line valve 402, command the WPD to start its sanitization procedure, and start the HDD sanitization procedure. If disinfection of the line between devices 400 fails, the user is notified and the WPD is commanded to suspend water production 468. The HDD controller in these circumstances optionally initiates a procedure to re-prime its flow paths and resets the sanitization timers at 472. The HDD controller can then wait for input from the user 474 to retry the sanitization procedure or not. Otherwise, the HDD can optionally initiate a 476 service call. The controller can provide the appropriate instructions to a user at the user interface, or can be configured to automatically send the appropriate messages to a remote server and service center via of an Internet communication link. hR^n Ln / nznz / E / Yi The HDD controller can command the WPD into a flush mode, in which water from the source flows into the system and through any of the system's filters. This is commonly done after a filter replacement. If a filter replacement (for example, a carbon filter) is indicated, the HDD controller may first command the WPD to an idle state, followed by alerting a user in a graphical user interface that the WPD is ready to replace your filter. Once the user indicates the completion of this task, the HDD may command the WPD to a standby state, followed by a download mode. The HDD commands to return to the standby state upon completion of this task, so that a state of water production can be promptly initiated at the start of therapy. Discharge mode can also be commanded prior to fluid sampling to ensure a more reliable indication of filters quality. It can also be ordered if the WPD system has been in an idle or standby state for more than a predetermined amount of time. Status messages may be sent between a water layer of the HDD system controller architecture and a therapy layer of the HDD system controller architecture. Example messages that the water layer may receive from the WPD may include: -The current operational status of the WPD - The identification code or identifier of the current WPD - The date the WPD filter was installed - If it is necessary to replace the filter - If communication with the WPD has been lost - If the WPD indicates an operational error - If the WPD indicates a failsafe error - The time elapsed since the last disinfection of the WPD - If necessary, disinfect the WPD - The software version installed on the WPD system controller Status messages related to the operational state of the WPD may include one or more of the following: -WPD active (independent of HDD); the initiation of the communication link between HDD and WPD causes the HDD to command the WPD to the standby state. - WPD at rest; the product valve is closed. - WPD standby; the product valve is open. - WPD that produces water at normal temperature; the product valve is open. - WPD awaiting filter replacement; the product valve is closed. - WPD filter and washing lines after filter replacement. hR^n Ln / nznz / E / Yi Ln / nznz / E / Yi - WPD producing hot water; product; the valve opens when it is at temperature. - WPD disinfection; the product valve is closed. - WPD producing a water sample for analysis (for example, chloramine analysis); the product valve is closed. - WPD waiting for user input in the GUI to supply a water sample for testing. - WPD is in a fail-safe state; the product valve is closed. Preferably, the HDD controller commands the WPD to remain in standby mode as long as it is not performing any other operation. If it is in another operation (for example, cleaning), the HDD controller waits for this operation to complete. Once the WPD is in standby mode, the HDD controller can check if the WPD should perform a filter cleaning operation. If so, the WPD initiates a filter flush operation. The HDD can also command a filter flush operation if, for example, there is a power interruption before a filter flush has been completed after replacing the filter. Optionally, prior to the start of water production for a therapy, the HDD can be programmed to require the user to sample the WPD product water for various contaminants, such as chloramine. The HDD can direct the WPD to initiate a state of water sampling. When the WPD indicates a ready condition for sampling. The HDD then alerts the user to collect and test a water sample. If the user indicates that the sample has passed the test, the HDD can command the WPD to start producing water for a therapy. Optionally, the HDD can command the WPD to enter a wait state if the user indicates that the sample failed the test. Errors originating from the WPD during water production can be reported to the HHD, which can then send a command to acknowledge the error condition and issue an alert via an interface (for example, the HDD interface) to the user. . The WPD controller then waits for a command from the user to try to resume water production or go into a wait state. A failsafe error condition would typically stop WPD operations and instruct the HDD to initiate an end of therapy procedure. Ln / nznz / E / Yi NOVELTY OF THE INVENTION

Claims

1. A fluid handling cassette assembly comprising: an intermediate cassette interposed between a first outer cassette and a second outer cassette; each of said cassettes comprising: an intermediate plate positioned between a first plate and a second plate, said plates having a length, width, and plate thickness; a first side of the intermediate plate opposite the first plate and a second side of the intermediate plate opposite the second plate; the first plate separated from the intermediate plate defining a width of a first interplate space, and the second plate separated from the intermediate plate defining a width of a second interplate space; a cassette edge having a cassette thickness defined by the thickness of each plate plus the width of the first and second interplate spaces, and a cassette face defined by the length and width of the first or second plate;a plurality of diaphragm valves or pumps comprising valve or pump actuating chambers connected to actuating channels running parallel to the cassette face within the first or second plate space, and terminating at the respective valve or pump actuating ports of the cassette on a first cassette edge between the first or second plate space; and a fluid handling capsule positioned in an intercassette space between the central cassette and the first or second cassette; said capsule having a fluid connection to fluid channels in the intermediate, first, or second cassette through a fluid conduit penetrating the face of the intermediate, first, or second cassette;where the first edge of the intermediate, first, and second cassettes are located on a first side of the cassette assembly, such that the valve or pump actuation ports of the cassette are configured to plug in or unplug an actuation port receptacle assembly opposite the first side of the cassette assembly. 2 - The cassette assembly according to claim 1, further characterized in that the fluid handling capsule comprises a diaphragm pump capsule having an actuation and a fluid connection to the actuation and fluid channels in the intermediate cassette, first or second, through an actuation conduit and a fluid conduit, each of which penetrates the face of the intermediate cassette, first or second.

3. The cassette assembly according to claim 2, further characterized in that the actuating conduit of the diaphragm pump capsule is connected to an actuating channel in a first or second space between plates of said intermediate cassette, first or second, and has an uninterrupted connection to a cassette actuating port for the Ln / nznz / E / Yi capsule of the diaphragm pump on the first edge of said intermediate cassette, first or second.

4. The cassette assembly according to claim 2, further characterized in that the fluid conduit of the diaphragm pump capsule is connected to a fluid channel in a first or second space between plates of said intermediate cassette, first or second, and is connected to a diaphragm valve in said cassette, and wherein an actuation channel of said diaphragm valve is connected to an actuation port of the cassette for said diaphragm valve on the first edge of said intermediate cassette, first or second.

5. The cassette assembly according to claim 1, further characterized in that the fluid conduit is rigid.

6. The cassette assembly according to claim 5, further characterized in that it comprises a plurality of fluid handling capsules between the intermediate cassette and the first cassette, and between the intermediate cassette and the second cassette, and wherein the associated fluid conduits of this plurality of fluid handling capsules are rigid and provide structural support for the cassette assembly.

7. The cassette assembly according to claim 1, further characterized in that it comprises a cassette mounting frame configured to improve the structural rigidity of the cassette assembly, the cassette mounting frame comprising a rigid support plate on a second side of the cassette assembly opposite the first side of the cassette assembly, said support plate being configured to engage with a cassette loading apparatus opposite the actuation port receptacle.

8. A fluid handling cassette assembly comprising: an intermediate cassette interposed between a first outer cassette and a second outer cassette; each of said cassettes comprising: an intermediate plate positioned between a first plate and a second plate, said plates having a length, width, and plate thickness; a first side of the intermediate plate opposite the first plate and a second side of the intermediate plate opposite the second plate; the first plate separated from the intermediate plate defining a width of a first interplate space, and the second plate separated from the intermediate plate defining a width of a second interplate space; a cassette edge having a cassette thickness defined by the thickness of each plate plus the width of the first and second interplate spaces, and a cassette face defined by the length and width of the first or second plate;a plurality of diaphragm valves or pumps comprising valve or pump actuating chambers connected to actuating channels running parallel to the cassette face within the first or second plate space, and terminating at the respective valve or pump actuating ports of the cassette on a first cassette edge between the first or second plate space; a first fluid handling capsule positioned in an intercassette space between the intermediate cassette and the first or second cassette; said capsule having a fluid connection to fluid channels in the intermediate, first, or second cassette via a fluid conduit penetrating the face of the intermediate, first, or second cassette;and a second fluid handling capsule comprising a diaphragm pump capsule having an actuation and fluid connection to the actuation and fluid channels in the intermediate, first, or second cassette via an actuation conduit and a fluid conduit, each penetrating the face of the intermediate, first, or second cassette; wherein the first edge of the intermediate, first, and second cassettes is located on a first side of the cassette assembly, such that the actuation ports of the cassette valve or pump are configured to plug in or unplug an actuation port receptacle assembly opposite the first side of the cassette assembly; 9. The cassette assembly according to claim 8, further characterized in that the actuating conduit of the diaphragm pump capsule is connected to an actuating channel in a first or second space between plates of said intermediate cassette, first or second, and has an uninterrupted connection to an actuating port of the cassette for the diaphragm pump capsule on the first edge of said intermediate cassette, first or second.

10. The cassette assembly according to claim 8, further characterized in that the fluid conduit of the diaphragm pump capsule is connected to a fluid channel in a first or second space between plates of said intermediate cassette, first or second, and is connected to a diaphragm valve in said cassette, and wherein an actuation channel of said diaphragm valve is connected to an actuation port of the cassette for said diaphragm valve on the first edge of said intermediate cassette, first or second. 11 - The cassette assembly according to claim 8, further characterized in that the fluid conduit is rigid. 12.- The cassette assembly according to claim 11, further characterized in that it comprises a plurality of fluid handling capsules between the intermediate cassette and the first cassette, and between the intermediate cassette and the second cassette, and wherein the associated fluid conduits of this plurality of fluid handling capsules are rigid, providing structural support for the cassette assembly.

13. The cassette assembly according to claim 8, further characterized in that it comprises a cassette mounting frame configured to improve the structural rigidity of the cassette assembly, the cassette mounting frame comprising a rigid support plate on a second side of the cassette assembly opposite the first side of the cassette assembly, said support plate being configured to engage with a cassette loading device opposite the actuation port receptacle. Ln / nznz / E / Yi 14. A fluid handling cassette comprising an intermediate plate positioned between a first plate and a second plate, said plates having a length, width and plate thickness, a first side of the intermediate plate opposite the first plate and a second side of the intermediate plate opposite the second plate; the first plate separated from the intermediate plate defining a width of a first interplate space, and the second plate separated from the intermediate plate defining a width of a second interplate space; a cassette edge having a cassette thickness defined by the thickness of each plate plus the width of the first and second interplate spaces, and a cassette face defined by the length and width of the first or second plate;The intermediate plate comprises a pumping station defined by a pump diaphragm and the first side of the intermediate plate, said pump diaphragm seating against the first side of the intermediate plate and having an excursion range defined by the width of the first plate space; and a pump actuation channel running parallel to the face of the cassette in the first plate space connecting a pump actuation chamber bounded by the first plate and the pump diaphragm to a pump actuation port of the cassette located within the first plate space on a first edge of the cassette.

15. The cassette according to claim 14, further characterized in that it comprises a first and a second pump fluid port in the pumping station that fluidly connects a respective first and second fluid channel in the second space between plates to a pumping chamber defined by the pump diaphragm and the first side of the intermediate plate.

16. The cassette according to claim 14, further characterized in that it comprises a pump fluid port in the pumping station that fluidly connects a fluid channel in the second space between plates with a pumping chamber defined by the pump diaphragm and the first side of the intermediate plate. 17.- The cassette according to claim 14, further characterized in that it comprises an opening in the intermediate plate in the pumping station, said opening allowing the pump diaphragm to move from the first plate to the second plate when actuated by positive or negative pressure supplied through the pump actuation channel.

18. The cassette according to claim 14, further characterized in that the plates are not thick enough to allow the fluid or actuation channels to move within the plates in a direction parallel to the face of the cassette.

19. The cassette according to claim 14, further characterized in that it comprises a fluid channel running in the second space between plates and fluidly connected to a pumping chamber defined by the pump diaphragm and the first side of the intermediate plate, said connection being made through one or more pumping fluid ports in the intermediate plate, wherein the fluid channel runs parallel to the face of the cassette in the second space between plates connecting the pumping chamber to a fluid port of the cassette located within the second space between plates on the first edge or on a second edge of the cassette.

20. A fluid handling cassette comprising an intermediate plate positioned between a first plate and a second plate, said plates having a length, width and plate thickness, a first side of the intermediate plate opposite the first plate and a second side of the intermediate plate opposite the second plate; the first plate separated from the intermediate plate defining a width of a first interplate space, and the second plate separated from the intermediate plate defining a width of a second interplate space; a cassette edge having a cassette thickness defined by the thickness of each plate plus the width of the first and second interplate spaces, and a cassette face defined by the length and width of the first or second plate;The intermediate plate comprises a valve station defined by a valve diaphragm and the first side of the intermediate plate, said valve diaphragm seating against the first side of the intermediate plate and having an excursion range defined by the width of the first interplate space; and a valve actuation channel running parallel to the cassette face in the first interplate space connecting a valve actuation chamber bounded by the first plate and the valve diaphragm to a cassette valve actuation port located within the first interplate space on a first edge of the cassette.

21. The cassette according to claim 20, further characterized in that it comprises a first and a second valve fluid port in the valve station fluidly connecting a respective first and second fluid channel in the second space between plates to a valve fluid chamber defined by the valve diaphragm and the first side of the intermediate plate. 22.- The cassette according to claim 21, further characterized in that one or both valve fluid ports comprise a raised valve seat for sealing the valve diaphragm over the first or second valve fluid port when positive pressure is applied to the valve diaphragm through the valve actuating channel.

23. The cassette according to claim 21, further characterized in that the first fluid channel is fluidly isolated from the second fluid channel through the fluid ports of the first and second valves.

24. The cassette according to claim 20, further characterized in that it comprises a fluid channel running in the second space between plates, and fluidly connected to a valve fluid chamber defined by the valve diaphragm and the first side of the intermediate plate, said connection being made through two valve fluid ports in the intermediate plate, wherein the fluid channel runs parallel to the face of the cassette in the second space between plates connecting the valve fluid chamber with a cassette fluid port located within the second space between plates on the first edge or on a second edge of the cassette.

25. A fluid handling cassette comprising an intermediate plate positioned between a first plate and a second plate, said plates having a length, width and plate thickness, a first side of the intermediate plate opposite the first plate and a second side of the intermediate plate opposite the second plate; the first plate separated from the intermediate plate defining a width of a first interplate space, and the second plate separated from the intermediate plate defining a width of a second interplate space; a cassette edge having a cassette thickness defined by the thickness of each plate plus the width of the first and second interplate spaces, and a cassette face defined by the length and width of the first or second plate;the intermediate plate comprising a pumping station defined by a pump diaphragm and the first side of the intermediate plate, said pump diaphragm being seated against the first side of the intermediate plate and having an excursion in the range defined by the width of the first space between plates; the intermediate plate also comprising first and second valve stations, each defined by a valve diaphragm and the first side of the intermediate plate, said valve diaphragm being seated against the first side of the intermediate plate and having an excursion range defined by the width of the first space between plates; and a pump actuation channel for the pumping station and a valve actuation channel for each of the first and second valve stations;said pump actuation channel runs parallel to the face of the cassette in the first space between plates, connecting a pump actuation chamber bounded by the first plate and the pump diaphragm with a cassette pump actuation port located within the first space between plates on a first edge of the cassette; and each valve actuation channel runs parallel to the face of the cassette in the first space between plates, connecting a valve actuation chamber bounded by the first plate and the valve diaphragm with a cassette valve actuation port located within the first space between plates on the first edge of the cassette.

26. The cassette according to claim 25, further characterized in that it comprises an inlet and outlet valve fluid port in each of said two valve stations, and one or more pump fluid ports in the pumping station, each of said valve and pump fluid ports fluidly connecting a fluid channel in the second space between plates with: a pumping chamber defined by the pump diaphragm and the first side of the intermediate plate; and a valve fluid chamber in each of said valve stations defined by the corresponding valve diaphragm and the first side of the intermediate plate; the fluid channel having a flow path passing through said Ln / nznz / E / Yi inlet and outlet valve fluid ports and said one or more pump fluid ports;wherein the selective actuation of the pump actuating chamber and said valve actuating chambers allows unidirectional flow of a fluid through the fluid channel.

27. The cassette according to claim 25, further characterized in that it comprises a fluid channel running in the second space between plates and fluidly connected to: a pumping chamber defined by the pump diaphragm and the first side of the intermediate plate, said connection being made through a pump fluid port in the intermediate plate; and a valve fluid chamber of each valve station, each valve fluid chamber being defined by the corresponding valve diaphragm and the first side of the intermediate plate, each of said connections being made through two valve fluid ports in the intermediate plate;wherein the fluid channel runs parallel to the face of the cassette in the second space between plates connecting the pumping chamber and each of the valve's fluid chambers with a cassette fluid inlet port and a cassette fluid outlet port located within the second space between plates on the first edge or on a second edge of the cassette.

28. The cassette according to claim 27, further characterized in that the cassette fluid inlet port and the cassette fluid outlet port are located on a second edge of the cassette, such that the cassette pump actuation port and the cassette valve actuation port are configured to connect directly to an external coupling activation receptacle, and such that the fluid inlet port and the fluid outlet port are arranged to connect via a flexible or malleable tube to a fluid source or destination external to the cassette.

29. The cassette according to claim 25, further characterized in that it comprises a fluid channel running in the second space between plates and fluidly connected to: a pumping chamber defined by the pump diaphragm and the first side of the intermediate plate, said connection being made through a pump fluid port in the intermediate plate; and a valve fluid chamber of each valve station, each valve fluid chamber being defined by the corresponding valve diaphragm and the first side of the intermediate plate, each of said connections being made through two valve fluid ports in the intermediate plate;wherein the fluid channel runs parallel to the cassette face in the second space between plates and connects the pumping chamber and each of the valve fluid chambers to a cassette fluid inlet port and a cassette fluid outlet port, said cassette fluid inlet port and fluid outlet port exiting the cassette through rigid conduits originating in the intermediate plate and penetrating the cassette face through the first or second outer plates. Ln / nznz / E / Yi; 30. The cassette according to any of claims 14, 20, 25, further characterized in that it comprises a plurality of walls formed on the first and second sides of the intermediate plate, said walls arranged to merge with the first and second plates to form said actuation or fluid channels within the cassette.

31. The cassette according to claim 30, further characterized in that a first type of said walls comprises parallel walls to define the actuation or fluid channels, and a second type of said walls comprises circumferential perimeter walls that define pump or valve actuation stations, and a third type of said walls comprises adjacent end walls that define a channel termination in which a valve or pump fluid port penetrates the intermediate plate.

32. The cassette according to claim 31, further characterized in that the first plate comprises one or more circumferential pump or valve diaphragm retainers configured to fit within the circumferential perimeter walls of the opposing intermediate plate defining pump or valve actuation stations, said retainers arranged to hold a peripheral bead or rim of an associated diaphragm positioned in the pump or valve station of the intermediate plate.

33. The cassette according to claim 32, further characterized in that the retainers include holes, fenestrations or slots to allow the transmission of actuating fluid or gas between the actuating chamber of the valve or pump surrounded by the retainer and an associated actuating channel.

34. The cassette according to claim 31, further characterized in that the first plate comprises an elongated rib configured to be placed within a matching actuation channel of the intermediate plate, the cross-sectional size and length of the rib being arranged to adjust the volume of the actuation channel to a predetermined value between an actuation port of the cassette and an actuation chamber of the associated valve or pump.

35. A fluid handling cassette comprising an intermediate plate positioned between a first plate and a second plate, said plates having a length, width and plate thickness, a first side of the intermediate plate opposite the first plate and a second side of the intermediate plate opposite the second plate; the first plate separated from the intermediate plate defining a width of a first interplate space, and the second plate separated from the intermediate plate defining a width of a second interplate space; a cassette edge having a cassette thickness defined by the thickness of each plate plus the width of the first and second interplate spaces, and a cassette face defined by the length and width of the first or second plate;The intermediate plate comprises a first and second valve station, the first valve station being defined by a first valve diaphragm and the first side of the intermediate plate, and the second valve station being defined by a second valve diaphragm and the second side of the intermediate plate, said first valve diaphragm seated against the first side of the intermediate plate and with an excursion range defined by the width of the first space between plates, and said second valve diaphragm seated against the second side of the intermediate plate and with an excursion range defined by the width of the second space between plates;and a first valve actuation channel for the first valve station running parallel to the cassette face in the first plate space, and a second valve actuation channel for the second valve station running parallel to the cassette face in the second plate space; said first valve actuation channel connecting a first valve actuation chamber limited by the first plate and the first valve diaphragm to a first cassette valve actuation port located within the first plate space on a first edge of the cassette; and said second valve actuation channel connecting a second valve actuation chamber limited by the second plate and the second valve diaphragm to a second cassette valve actuation port located within the second plate space on the first edge of the cassette.

36. A fluid handling cassette comprising an intermediate plate positioned between a first plate and a second plate, said plates having a length, width and plate thickness, a first side of the intermediate plate opposite the first plate and a second side of the intermediate plate opposite the second plate; the first plate separated from the intermediate plate defining a width of a first interplate space, and the second plate separated from the intermediate plate defining a width of a second interplate space; a cassette edge having a cassette thickness defined by the thickness of each plate plus the width of the first and second interplate spaces, and a cassette face defined by the length and width of the first or second plate;The intermediate plate comprises a first and a second pumping station, the first pumping station being defined by a first pump diaphragm and the first side of the intermediate plate, and the second pumping station being defined by a second pump diaphragm and the second side of the intermediate plate, said first pump diaphragm seated against the first side of the intermediate plate and having an excursion range defined by the width of the first space between plates, and said second pump diaphragm seated against the second side of the intermediate plate and having an excursion range defined by the width of the second space between plates; and a first pump actuation channel for the first pumping station running parallel to the face of the cassette in the first space between plates, and a second pump actuation channel for the second pumping station running parallel to the face of the cassette in the second space between plates;said first pump actuation channel connecting a first pump actuation chamber delimited by the first plate and the first pump diaphragm to a first cassette pump actuation port located within the first space between plates on a first edge of the cassette; and said second pump actuation channel connecting a second pump actuation chamber delimited by the second plate and the second pump diaphragm to a second cassette pump actuation port located within the second space between plates on the first edge of the cassette.

37. A manifold adapter configured to connect a pressure distribution manifold to a liquid handling cassette assembly comprising: a housing having a first side comprising a first set of transfer ports configured to connect to actuation outlet ports of the manifold, and having a second opposite side comprising a second set of transfer ports configured to connect to actuation inlet ports of the cassette assembly; the first set of transfer ports comprising a first spatial arrangement configured to match a spatial arrangement of the actuation outlet ports of the manifold; the second set of transfer ports comprising a second spatial arrangement configured to match a spatial arrangement of the actuation inlet ports of the cassette assembly;wherein the first spatial arrangement of transfer ports is different from the second spatial arrangement of transfer ports.; 38. The collector adapter according to claim 37, further characterized in that the first spatial arrangement covers an area of ​​the first side of the adapter housing having a first length and a first width, and the second spatial arrangement covers an area of ​​the second side of the adapter housing having a second length and a second width, wherein the second length is greater than the first length so that the collector adapter housing protrudes from one side of the collector.

39. The manifold adapter according to claim 37, further characterized in that the second side of the housing includes an elastomeric wiper gasket comprising a plurality of wiper seals, each of which is associated with a transfer port on the second side of the adapter housing, wherein the wiper gasket is embedded under a top plate of the adapter housing. 40.-A seat apparatus for a cassette having a plug-in side and an opposite mounting side, the seat apparatus comprising: a stationary frame member connected to a movable cassette mount by a plurality of links on a first side of the cassette mount and on a second opposite side of the cassette mount, the links on the first side of the cassette mount being connected to a first stationary tab of the stationary frame member, and the links on the second side of the cassette mount being connected to a second stationary tab of the stationary frame member; each of the links comprising a swing arm having a first end pivotally coupled to the stationary tab and a second end coupled to an elongated groove in the cassette mount;the second end of the swing arm being configured to move in an arced path to move the cassette mount, wherein the elongated slot restricts the movement of the cassette mount by the swing arm to a linear movement towards or away from the stationary frame member.

41. The seating apparatus according to claim 40, further characterized in that the cassette mount comprises a first movable tab and a first rail on the first side of the cassette mount, and a second movable tab and a second rail on the second side of the cassette mount, each of said movable tabs having a surface generally parallel to the direction of movement of the cassette mount, the elongated groove being formed in the movable tab and oriented perpendicular to the direction of movement of the cassette mount, and wherein the first and second rails are configured to support the mounting side of the cassette.

42. The seating apparatus according to claim 41, further characterized in that it comprises a handle assembly pivotally connected to the cassette mount, such that movement of a handle of the handle assembly in a direction away from the stationary frame member moves the cassette mount away from the stationary frame member, and movement of the handle in a direction towards the stationary frame member moves the cassette mount towards the stationary frame member.

43. The seat apparatus according to claim 42, further characterized in that the pivoting connection of the handle assembly comprises a first pivoting connection of a first handle arm to the first fixed tab, a second pivoting connection of a second handle arm to the second fixed tab, a third pivoting connection of the first handle arm to a tilting handle arm connected to the first movable tab of the cassette mount, a fourth pivoting connection of the second handle arm to a tilting handle arm connected to the second movable tab of the cassette mount, wherein the first and third pivoting connections and the second and fourth pivoting connections are separated from each other on the first and second handle arms.

44. The seating apparatus according to claim 42, further characterized in that it comprises a third stationary tab of the stationary frame member, said third stationary tab facing the handle assembly and generally perpendicular to the first and second stationary tabs, wherein the handle assembly includes a spring-loaded plunger configured to engage in a hole or recess in the third stationary tab, so that the cassette mount can be locked in a retracted position when the handle of the handle assembly is moved toward the stationary frame member.

45. A method for controlling a pneumatically actuated diaphragm pump comprising: opening a valve fluidly connecting a pneumatic pressure source to an actuating chamber of the diaphragm pump; monitoring one or more gas pressures in the actuating chamber of the diaphragm pump; closing the valve when the pressure in the actuating chamber is equal to or greater than the target pressure; and opening the valve when an average magnitude of the monitored pressures is less than the target pressure.

46. ​​The method according to claim 45, further characterized in that it also comprises the act of averaging the monitored pressures after the valve is closed.

47. The method according to claim 46, further characterized in that it also comprises the act of setting the average pressure to zero before the valve is closed.

48. The method according to claim 45, further characterized in that the valve is a binary valve.

49. The method according to claim 45, further characterized in that the pressure is monitored by a controller with a pressure sensor fluidly connected to the actuation chamber.

50. The method according to claim 49, further characterized in that the controller receives pressure information from the pressure sensor and uses said pressure information to control the valve.

51. A method for controlling a fluid flow rate of a pneumatically actuated diaphragm pump comprising: opening a valve for the first time by fluidly connecting a pneumatic pressure source to an actuating chamber of the diaphragm pump; monitoring one or more gas pressures in the actuating chamber of the diaphragm pump; recording the time of the first valve opening; closing the valve when the pressure in the actuating chamber is equal to or greater than the target pressure; opening the valve when an average magnitude of the monitored pressures falls below the target pressure; detecting the end of a pump stroke based on the monitored pressures; and recording the time of the end of the pump stroke.and change the target pressure based on a difference between the stroke duration and a predetermined target stroke duration, where the stroke duration is the time difference between the end of the pump stroke and the first opening of the valve.

52. The method according to claim 51, further characterized in that it further comprises the step of averaging the monitored pressures after the valve is closed.

53. The method according to claim 52, further characterized in that it also comprises the step of setting the average pressure to zero before the valve is closed. 54.- The method according to claim 53, further characterized in that the valve is a binary valve.

55. The method according to claim 51, further characterized in that the pressure is monitored by a controller using a pressure sensor fluidly connected to the actuation chamber.

56. The method according to claim 55, further characterized in that the controller controls the valve using information from the pressure sensor.

57. A method for controlling a pneumatically actuated diaphragm pump comprising: opening a valve fluidly connecting a pneumatic pressure source to an actuating chamber of the diaphragm pump; monitoring one or more gas pressures in the actuating chamber of the diaphragm pump; closing the valve when the pressure in the actuating chamber is equal to or greater than the target pressure; and opening the valve when an average magnitude of the monitored pressures is less than the target pressure by a predetermined value, wherein the predetermined value varies during one stroke of the diaphragm pump.

58. The method according to claim 57, further characterized in that the predetermined value varies according to the number of valve openings during the stroke.

59. The method according to claim 57, further characterized in that the default value varies depending on whether the diaphragm pump is filling or emptying.

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