pump

Abstract

The rotary pump (200) comprises a housing (205) having an inner surface (220) defining a cavity in which a first fluid port (210) and a second fluid port (215) and a rotor (225) are located, the rotor comprising a housing engaging surface area (235) which forms a sealing interference fit with the inner surface of the housing and a surface recess (250) which forms with the inner surface of the housing a fluid carrying chamber which carries fluid from the first fluid port to the second fluid port in response to rotation of the rotor, and a plurality of resiliently deformable diaphragms (255) providing a portion of the inner surface of the housing, each diaphragm comprising a rotor engaging surface (257) and a rear surface (260), the rotor engaging surfaces being urged into contact with the rotor by action of a pressure applying means (265) acting against the rear surface.

Description

Technical Field

[0001] The present invention relates to pumps, and more particularly to rotary pumps.

Background Art

[0002] There is known a pump formed by a housing containing a rotor having at least one surface recess that forms a chamber with the inner surface of the rotor and has an inlet and an outlet for a fluid, and conveys the fluid from the inlet to the outlet in response to rotation of the rotor. To prevent the fluid from passing from the outlet to the inlet, a flexible diaphragm is provided on or as part of the housing and is located between the inlet and the outlet. The diaphragm is urged to engage with the rotor by pressurizing means, which can take many forms such as a block of elastic material, an elastic tube of material, a spring, or hydraulic or pneumatic pressure. This general type of pump is disclosed in International Patent Application No. WO2006 / 027548.

[0003] Such pumps include a discrete number of chambers formed by recesses in the rotor surface that convey fluid from the inlet to the outlet, so the resulting liquid flow tends to be pulsed with periods of no flow and periods of high flow. This can be detrimental in some applications, for example, when administering drugs to patients where pulsed flow can be uncomfortable. The object of the present invention is to provide a pump with an improved flow profile.

[0004] Attempts have been made to reduce the pulsing of fluid flow in pumps such as the rotary injection pump described in International Patent Application No. WO2011 / 119464. This document discloses a pump having a housing containing a rotor, the rotor including a first ring of the surface that forms a channel with the housing and a second ring of the surface that forms a channel with the housing. The first and second rings are offset radially to attenuate the pulsing of fluid flow through the pump.

[0005] There is always a desire to provide smaller pumps with higher processing capacity. A preferred embodiment of the present invention is to provide a rotary pump with higher processing capacity for a given size. Furthermore, it is desirable to improve the flow rate relative to the output efficiency.

[0006] Furthermore, since they can be used as part of a single-use system, it is important that the pumps can be sterilized in many applications. The object of the present invention is to provide a pump that can be sterilized more easily.

[0007] An object of a preferred embodiment of the present invention is to provide a rotary pump that provides essentially continuous flow. Continuous flow, as used herein, is defined as a flow in which there are no periods without fluid flow. Continuous flow does not necessarily mean that there is a constant flow rate, but rather that there may be some fluctuation in the flow rate, provided that there is always a positive flow of fluid while the pump is operating and supplying fluid. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] International Publication No. 2006 / 027548 [Patent Document 2] International Publication No. 2011 / 119464 [Overview of the project] [Means for solving the problem]

[0009] Aspects of the present invention described herein may be useful alone or in combination with other aspects described herein.

[0010] According to a first aspect of the present invention, a pump comprising: a housing having an inner surface defining a first fluid port and a second fluid port and a cavity in which a rotor is located; a rotor rotatably mounted within the housing and having a longitudinal axis of rotation, comprising a housing engagement surface area forming a sealing interlock with the inner surface of the housing, and a surface recess forming a fluid transport chamber with the inner surface of the housing for transporting fluid from the first fluid port to the second fluid port in accordance with the rotation of the rotor; and a plurality of elastically deformable diaphragms each providing a portion of the inner surface of the housing, each diaphragm comprising a rotor engagement surface and a rear surface opposite to the rotor engagement surface, wherein the rotor engagement surface of each diaphragm is pressed to contact the rotor by the action of a pressurizing means acting on the rear surface of the diaphragm, and the number of elastically deformable diaphragms exceeds the number of surface recesses on the rotor. A pump is provided, comprising a rotor comprising an extension body and a drive shaft, wherein the extension body is substantially hollow and comprises separate first and second rotor cavities, the first rotor cavity having an opening at a first end of the rotor, and the second rotor cavity having an opening at a second end of the rotor, the rotor body further comprising a first opening between the first rotor cavity and a surface recess, and a second opening between the surface recess and the second rotor cavity, the pump being arranged such that when the rotor body is located within the housing cavity, a first fluid port is in fluid flow communication with the first rotor cavity through an opening at the first end of the rotor, and a second fluid port is in fluid flow communication with the second rotor cavity through an opening at the second end of the rotor, the pump being arranged such that when the rotor rotates, at least one of elastically deformable diaphragms is always bisect the first and second openings on the rotor surface recess.

[0011] According to a second aspect of the present invention, a pump comprising: a housing having an inner surface defining a cavity in which a rotor is located and a first fluid port and a second fluid port; a rotor rotatably mounted within the housing and having a longitudinal axis of rotation and having a housing engagement surface area that forms a sealing restraint fit with the inner surface of the housing and a surface recess that, together with the inner surface of the housing, forms a fluid transport chamber for transporting fluid from the first fluid port to the second fluid port in response to the rotation of the rotor, wherein the rotor is twisted about its longitudinal axis of rotation such that the first and second ends of the rotor are offset by at least 10 degrees relative to each other; and a resiliently deformable diaphragm providing a portion of the inner surface of the housing, the diaphragm comprising a rotor engagement surface and a rear surface opposite to the rotor engagement surface, wherein the rotor engagement surface of the diaphragm is pressed to contact the rotor by the action of a pressurizing means acting on the rear surface of the diaphragm A pump is provided, comprising a resilient diaphragm, the rotor comprising an extendable body and a drive shaft, the body being substantially hollow and comprising separate first and second rotor cavities, the first rotor cavity having an opening at a first end of the rotor, the second rotor cavity having an opening at a second end of the rotor, the rotor body further comprising a first opening between the first rotor cavity and a surface recess, and a second opening between the surface recess and the second rotor cavity, the pump being arranged such that when the rotor body is located within the housing cavity, a first fluid port is in fluid flow communication with the first rotor cavity through an opening at the first end of the rotor, and a second fluid port is in fluid flow communication with the second rotor cavity through an opening at the second end of the rotor, the pump being arranged such that when the rotor rotates, the resilient diaphragm is always bisecting the first and second openings on the rotor surface recess.

[0012] According to a third aspect of the present invention, a pump comprising: a housing having an inner surface defining a cavity in which a rotor is located and a first fluid port and a second fluid port; a rotor rotatably mounted within the housing and having a longitudinal axis of rotation, comprising a housing engagement surface area forming a sealing interlock with the inner surface of the housing, and a surface recess forming a fluid transport chamber with the inner surface of the housing for transporting fluid from the first fluid port to the second fluid port in response to the rotation of the rotor; and a resilient diaphragm providing a portion of the inner surface of the housing, wherein the diaphragm comprises a rotor engagement surface and a rear surface opposite to the rotor engagement surface, the rotor engagement surface of the diaphragm being pressed to contact the rotor by the action of a pressurizing means acting on the rear surface of the diaphragm, and linear ribs either extending upright from the rear surface of the resilient diaphragm or acting on the rear surface of the diaphragm, the linear ribs extending at least 10 degrees longitudinally from the rotor A pump is provided, comprising a resilient diaphragm angled with respect to a rotation axis, wherein the rotor comprises an extension body and a drive shaft, the body being substantially hollow and comprising separate first and second rotor cavities, the first rotor cavity having an opening at a first end of the rotor, the second rotor cavity having an opening at a second end of the rotor, the rotor body further comprising a first opening between the first rotor cavity and a surface recess, and a second opening between the surface recess and the second rotor cavity, the pump being arranged such that when the rotor body is located within the housing cavity, a first fluid port is in fluid flow communication with the first rotor cavity through an opening at the first end of the rotor, and a second fluid port is in fluid flow communication with the second rotor cavity through an opening at the second end of the rotor, the pump being arranged such that when the rotor rotates, the resilient diaphragm is always bisecting the first and second openings on the rotor surface recess.

[0013] Preferably, in all aspects of the present invention, the housing comprises an elastic material, such as polypropylene, polyethylene, thermoplastic polyurethane, or rubber. The first fluid port and / or second fluid port may extend from the housing. If the first fluid port and / or second fluid port extend from the housing, the first and / or second fluid ports are preferably molded together with the housing.

[0014] The rotor may be made from rigid materials such as stainless steel, polyetheretherketone (PEEK), high-density polyethylene (HDPE), or polycarbonate. The selection of materials for the housing and rotor is interdependent and should be chosen so that a low coefficient of friction exists between the contact surfaces of the housing and rotor.

[0015] According to all aspects of the present invention, the housing may comprise a single unit providing an inner surface, a first fluid port and a second fluid port defining a cavity in which the rotor is located, and optionally one or more elastically deformable diaphragms. Alternatively, the housing may provide an inner surface and optionally one or more elastically deformable diaphragms defining a cavity in which the rotor is located, and may be used in conjunction with first and / or second separate end caps to close the cavity in which the rotor is located. In this embodiment, the first and / or second fluid ports may be provided within the housing or within separate end caps.

[0016] A pump according to a second or third aspect of the present invention may include a single elastically deformable diaphragm.

[0017] Alternatively, a pump according to a second or third aspect of the present invention may comprise multiple elastically deformable diaphragms. A pump according to any aspect of the present invention may comprise any preferred number of elastically deformable diaphragms. In a preferred embodiment of any aspect of the present invention, the pump comprises two elastically deformable diaphragms. In an alternative preferred embodiment of any aspect of the present invention, the pump comprises three elastically deformable diaphragms. If the pump comprises multiple elastically deformable diaphragms, they are preferably arranged equidistant from the circumference of the rotor.

[0018] In all aspects of the present invention, one or all of the elastically deformable diaphragms are preferably provided by a housing section manufactured to a thickness sufficiently small to have the required deformable elasticity. For example, the elastically deformable diaphragms are provided by a housing section having a thickness of 1 mm or less, preferably 0.5 mm or less, and in some embodiments, less than 0.1 mm. In these embodiments, the housing is preferably made from an elastic thermoplastic or thermosetting material, and each elastically deformable diaphragm is integral with the housing.

[0019] Alternatively, in all aspects of the present invention, one or all of the elastically deformable diaphragms may comprise a portion of an elastically deformable elastomer material that is sealed and mounted to or co-molded with the housing. The separate diaphragm should be mounted to the housing to produce a sealed continuous rotor engagement surface as the inner surface of the housing, and preferably comprises an elastomer material such as thermoplastic elastomer (TPE) or thermoplastic polyurethane (TPU). If the diaphragm is provided by a separate elastically deformable elastomer material, the housing may comprise an elastic material, such as polypropylene, polyethylene, thermoplastic polyurethane, or rubber, or the housing may be made from a rigid material.

[0020] During use, according to all aspects of the present invention, each diaphragm forms a liquid-tight contact between the rotor engagement surface of the diaphragm and the rotor surface. Furthermore, the elastically deformable nature of each diaphragm means that during use, each diaphragm conforms to the contoured surface of the rotor so that it is operable to displace fluid from the fluid transport chamber as the rotor rotates.

[0021] In first and second aspect embodiments of the present invention, one or each of the elastically deformable diaphragms may be provided with linear ribs protruding from their rear surface. Alternatively, the ribs may be provided on spring means that, when in use, act on the rear surface of one or each of the diaphragms. In the first or second aspect embodiment of the present invention, the ribs extend along the entire length of the diaphragm in a direction parallel to the longitudinal axis of rotation of the rotor. Alternatively, in the first or second aspect embodiment of the present invention, the linear ribs extend along the entire length of the diaphragm and are angled at least 10 degrees with respect to the longitudinal axis of rotation of the rotor.

[0022] In all aspects of the present invention, any suitable pressurizing means may be used to press the rotor-engaging surface of each diaphragm to contact the rotor. The pressurizing means may comprise a spring means acting against the rear surface of one or each elastically deformable diaphragm. For example, the pressurizing means may comprise a block or tube of elastic material to which pressure is applied, thereby pressing the spring means against the rear surface of one or each elastically deformable diaphragm. An embodiment of a suitable spring member is disclosed in International Patent Application WO2013 / 117486. Alternatively, or in addition, the pressurizing means may comprise a fluid applied to the rear surface of one or each elastically deformable diaphragm. Embodiments of pumps comprising a fluid applied to the rear surface of elastically deformable diaphragms are disclosed in International Patent Applications WO2010 / 122299 and WO2014 / 135563.

[0023] In embodiments of all aspects of the present invention, the pump according to the present invention may comprise a diaphragm chamber surrounding the rear face of an elastically deformable diaphragm.

[0024] In all aspects of the present invention, the diaphragm chamber may be provided by a wall extending from the housing and preferably comprises a separate cap for closing the chamber. Alternatively, the diaphragm chamber may comprise a separate unit attached to the housing. The diaphragm chamber preferably houses pressurizing means arranged to press against an elastically deformable diaphragm relative to the rotor. Each diaphragm chamber may comprise either an open chamber or a closed chamber for arranging the pressurizing means. The closed chamber may be sealed hermetically.

[0025] In embodiments of all aspects of the present invention, the diaphragm chamber may be a closed chamber connected by a passage to the fluid flowing through the pump such that the fluid flowing through the pump provides the pressurizing means. The passage for providing fluid to the diaphragm chamber comprises a one-way valve allowing fluid to flow into the diaphragm chamber but not allowing it to flow out. This one-way valve arrangement allows for a sustained pressure against the diaphragm once the diaphragm chamber is loaded with fluid even when the direction of flow of the pump is reversed.

[0026] Alternatively, in embodiments of all aspects of the present invention, the diaphragm chamber may be a closed chamber connected by a passage to a separate fluid source which provides the pressurizing means.

[0027] In embodiments of all aspects of the present invention, a second fluid port may extend from the diaphragm chamber. Further, if the diaphragm chamber comprises a separate cap for closing the chamber, the second fluid port may extend from the cap.

[0028] In all aspects of the present invention, the diaphragm chamber surrounds a single elastically deformable diaphragm. Alternatively, individual diaphragm chambers may surround the respective rear surfaces of the elastically deformable diaphragms.

[0029] In alternative embodiments of all aspects of the present invention, each elastically deformable diaphragm is surrounded by a separate diaphragm chamber, and a plurality of diaphragm chambers are interconnected to effectively produce a single diaphragm chamber. The plurality of diaphragm chambers may be interconnected by providing fluid channels between the chambers. This is particularly useful when a second fluid port of the pump extends from the diaphragm chamber, and / or when fluid from a second rotor cavity provides pressurizing means.

[0030] In all aspects of the present invention, the rotor is substantially cylindrical and comprises at least one recess that, together with the inner surface of the housing, forms a fluid transport chamber. In all aspects of the present invention, the surface recess is provided by a concave area on the rotor surface. In all aspects of the present invention, the surface recess preferably extends longitudinally along most of the axial length of the rotor. In a preferred embodiment, the surface recess does not extend along the entire axial length of the rotor, but preferably extends longitudinally substantially along the entire axial length of the rotor. In embodiments in which the rotor comprises multiple recesses, the multiple recesses are distinct and do not intersect.

[0031] In all aspects of the present invention, the rotor may have a plurality of surface recesses that, together with the inner surface of the housing, form a plurality of corresponding fluid transport chambers that transport fluid from a first fluid port to a second fluid port as the rotor rotates. For example, the rotor may have two surface recesses that, together with the inner surface of the housing, form two fluid transport chambers. In alternative aspects of the present invention, the rotor has three surface recesses that, together with the inner surface of the housing, form three fluid transport chambers. The rotor may have four surface recesses that, together with the inner surface of the housing, form four fluid transport chambers. Furthermore, the rotor may have five surface recesses that, together with the inner surface of the housing, form five fluid transport chambers. The rotor in all aspects of the present invention may have any number of recesses that provide a corresponding number of fluid transport chambers, but the more chambers there are, the smaller the volume of fluid that can be transported in each chamber with respect to a given rotor diameter and length.

[0032] Preferably, if a pump according to any aspect of the present invention has a plurality of surface depressions, the plurality of surface depressions are arranged circumferentially with respect to the rotor. Preferably, the plurality of surface depressions are equidistant from the circumference of the rotor. In all aspects of the present invention, the plurality of depressions are not arranged longitudinally along the axial length of the rotor.

[0033] In all aspects of the present invention, the rotor may have two recesses and a substantially cylindrical shape with a circular cross-section at each end and an elliptical cross-section at the center.

[0034] In all alternative embodiments of the present invention, the rotor may have three recesses with circular cross-sections at each end and a substantially triangular cross-section at the center. In all alternative embodiments of the present invention, the rotor may have four recesses with circular cross-sections at each end and a substantially square cross-section at the center. In all alternative embodiments of the present invention, the rotor may have five recesses with circular cross-sections at each end and a substantially hexagonal cross-section at the center.

[0035] Preferably, the housing engagement surface area, which forms a sealing restraint fit with the inner surface of the housing, constitutes the entire cylindrical surface of the rotor, except for one or more surface depressions on the rotor. Preferably, the rotor comprises a substantially cylindrical body on which one or more surface depressions are formed. The housing engagement surface area of ​​the rotor preferably comprises cylindrical areas at each end of the rotor on which no surface depressions are formed, and these cylindrical areas are connected by extensions of the rotor surface that separate the longitudinal range of adjacent depressions. The cylindrical areas at the ends of the rotor and the extensions between adjacent depressions are connected and lie in the same cylindrical plane that defines the cylindrical surface of the rotor. The extensions of the rotor surface that separate adjacent depressions provide lands between adjacent depressions on the rotor surface.

[0036] In a second or third embodiment of the present invention, the pump may comprise an equal number of elastically deformable diaphragms and surface depressions on the rotor. For example, a pump according to a second or third embodiment of the present invention may comprise two elastically deformable diaphragms and two surface depressions on the rotor, which together with the inner surface of the housing form two fluid transport chambers.

[0037] In other embodiments of the second or third aspects of the present invention, the number of elastically deformable diaphragms exceeds the number of surface recesses on the rotor. For example, according to all aspects of the present invention, the pump may have three elastically deformable diaphragms and two surface recesses on the rotor, which together with the interior of the housing form two fluid transport chambers.

[0038] Pumps with multiple diaphragms have the advantage of being able to operate at a higher capacity compared to pumps with a single diaphragm. For example, a pump with two diaphragms and a rotor with two depressions will produce twice the flow of a pump with one diaphragm and a rotor with two depressions, because each depression is emptied twice in one swirl.

[0039] In all aspects of the present invention, the rotor comprises an extended body, which is substantially hollow, and comprises a first rotor cavity and a second rotor cavity. The first and second rotor cavities may be arranged continuously along the height of the rotor. Alternatively, the first and second rotor cavities may extend longitudinally along the length of the rotor and be arranged side by side. Preferably, the first and second rotor cavities are separated from each other by a partition wall. If the first and second rotor cavities are arranged continuously along the length of the rotor, the partition wall preferably extends across the entire cross-section inside the rotor body. If the first and second rotor cavities are arranged side by side, the partition wall preferably extends along the entire length inside the rotor body. If the partition wall extends along the entire length inside the rotor body, it may be curved, staggered, or angled, but the first and second rotor cavities must remain separated by the partition wall. In all embodiments, the first rotor cavity and the second rotor cavity are not in direct fluid communication.

[0040] In all aspects of the present invention, the first rotor cavity has an opening at the first end of the rotor to provide a first fluid port and the first rotor cavity for direct fluid communication. In a preferred embodiment, the opening extends substantially across the entire first end of the first rotor cavity.

[0041] In all aspects of the present invention, the second rotor cavity has an opening at the second end of the rotor to position the second rotor cavity to be in direct fluid communication with the second fluid port. In a preferred embodiment, the opening extends substantially across the entire second end of the second rotor cavity.

[0042] In all aspects of the present invention, the rotor body comprises a first opening between a first rotor cavity and a surface recess, and a second opening between the surface recess and a second rotor cavity. Preferably, the first and second openings are provided by slots within the rotor body, respectively.

[0043] In all aspects of the present invention, the rotor may include a first groove and a second groove in the surface of the rotor, extending substantially along the entire length of the opposing longitudinal edges of the surface recess, wherein a first opening between the first rotor cavity and the surface recess extends along a portion of the first groove overlying the first rotor cavity, and a second opening between the surface recess and the second rotor cavity extends along a portion of the second groove overlying the second rotor cavity.

[0044] Preferably, in all aspects of the present invention, the first opening between the first rotor cavity and the surface recess is located adjacent to, and preferably continuous with, the edge of the recess that forms the leading edge when the rotor rotates, and the second opening between the second rotor cavity and the surface recess is located adjacent to, and preferably continuous with, the opposing edge of the recess that forms the trailing edge when the rotor rotates.

[0045] In all aspects of the present invention, a first opening between a first rotor cavity and a surface recess extends along the entire axial length of the surface recess that sits atop the first rotor cavity and continues through the first end of the rotor. Alternatively, or in addition, in all aspects of the present invention, a second opening between a surface recess and a second rotor cavity extends along the entire axial length of the surface recess that sits atop the second rotor cavity and continues through the second end of the rotor. In these embodiments, the first opening and / or the second opening will extend through the housing engagement surface area at the end of the rotor. Extending the first and / or the second opening through the housing engagement surface area at the end of the rotor is advantageous because it means that the pumped fluid provides lubrication and cooling effects between the housing engagement surface area of ​​the rotor and the inner surface of the housing.

[0046] In the first and third lateral embodiments of the present invention, both the first and second openings are substantially parallel to the longitudinal axis of rotation of the rotor.

[0047] In a second aspect of the present invention, twisting the rotor has the effect of twisting the depressions on the rotor surface and the lands extending between the first and second rotor cavities and depressions. If the first opening between the first rotor cavity and the surface depression and the second opening between the surface depression and the second rotor cavity are provided by slots in the rotor body, these slots are also angled with respect to the longitudinal axis of rotation of the rotor in the direction in which the rotor is twisted. The lands between the slots and depressions are preferably substantially parallel.

[0048] In all aspects of the present invention, the first opening between the first rotor cavity and the surface recess extends along substantially the entire axial length of the surface recess that sits atop the first rotor cavity, and the second opening between the surface recess and the second rotor cavity extends along substantially the entire axial length of the surface recess that sits atop the second rotor cavity.

[0049] In all aspects of the present invention, the first opening between the first rotor cavity and the surface recess and the second opening between the surface recess and the second rotor cavity may be of any preferred shape, for example, the opening may be substantially linear, straight, oval, elongated oval, or tapered. Preferably, in all aspects of the present invention, the first opening between the first rotor cavity and the surface recess extends along the leading edge of the recess substantially parallel to the land between adjacent recesses. Preferably, in all aspects of the present invention, the second opening between the second rotor cavity and the recess extends along the trailing edge of the recess substantially parallel to the land between adjacent recesses. In both cases, the first and second openings are preferably adjacent to the land.

[0050] In all aspects of the present invention, which comprises a plurality of surface recesses, each surface recess preferably comprises a first opening between a first rotor cavity and the surface recess and a second opening between a second rotor cavity and the surface recess.

[0051] In all aspects of the present invention, the rotor drive shaft preferably extends from the hollow interior of the rotor body. The drive shaft may be a separate component fixed to the rotor, or it may be integral with the rotor. Preferably, the drive shaft extends from a partition formed inside the rotor body that separates the first rotor cavity and the second rotor cavity.

[0052] In all aspects of the present invention, the rotor may be twisted about its longitudinal axis such that the first and second ends of the rotor are offset from each other by at least 10 degrees, or at least 15 degrees, or at least 20 degrees. In all aspects of the present invention, the rotor may be twisted about its longitudinal axis such that the first and second ends of the rotor are offset from each other by 45 degrees or less, or 40 degrees or less.

[0053] In a third aspect embodiment of the present invention, the linear ribs may be angled with respect to the longitudinal axis of rotation of the rotor by at least 10 degrees, or at least 15 degrees, or at least 20 degrees. In a third aspect embodiment of the present invention, the linear ribs may be angled with respect to the longitudinal axis of rotation of the rotor by only 45 degrees or less, or 40 degrees or less.

[0054] In a first or second aspect embodiment of the present invention, the pump further comprises linear ribs that are either upright from or acting toward the rear surface of a resiliently deformable diaphragm, the linear ribs being angled with respect to the longitudinal axis of rotation of the rotor by at least 10 degrees, or at least 15 degrees, or at least 20 degrees. In a first or second aspect embodiment of the present invention, the pump comprises linear ribs that are either upright from or acting toward the rear surface of a resiliently deformable diaphragm, the linear ribs being angled with respect to the longitudinal axis of rotation of the rotor by only 45 degrees or less, or 40 degrees or less.

[0055] In an embodiment of the present invention, the rotor is twisted and the pump has linear ribs, the ribs either protruding from or acting against the rear surface of the diaphragm, and the ribs are angled with respect to the longitudinal axis of the rotor, the rotor is twisted in the opposite direction to the angle of the ribs.

[0056] In embodiments having multiple surface depressions, and therefore multiple first openings between the first rotor cavity and the surface depressions and multiple second openings between the second rotor cavity and the surface depressions, a single first rotor cavity can simultaneously supply fluid to multiple fluid transport cavities through the multiple first openings, and the second rotor cavity can simultaneously receive fluid from the fluid transport cavities through the second openings.

[0057] Preferably, a pump according to all aspects of the present invention comprises only a single rotor.

[0058] The combination of first and second rotor cavities, first and second openings between the rotor cavities and surface recesses, and a resiliently deformable diaphragm improves the consistency of the fluid flow rate provided and, in some embodiments of all aspects of the invention, allows the pump to be arranged to provide a continuous flow rate. Different combinations of the number of diaphragms and the number of recesses on the rotor will produce different flow profiles of the fluid through the pump.

[0059] A pump according to a first aspect of the present invention, comprising an even number of diaphragms and an odd number of fluid transport chambers, will provide continuous fluid flow. A pump according to a first aspect of the present invention, comprising an odd number of diaphragms and an even number of fluid transport chambers, will provide continuous fluid flow.

[0060] In pumps with a twisted rotor, the fluid transport chamber is emptied over the larger rotations of the rotor, which delivers a smoother flow profile. It is conceivable to overlap the individual flow profiles from each fluid transport chamber so that the combined flow output is continuous with less variation in flow rate.

[0061] In all aspects of the present invention, which involve multiple diaphragms, the diaphragms are preferably spaced equidistant from the circumference of the cavity in which the rotor is located. In all aspects of the present invention, which involve multiple recesses on the rotor, the recesses are preferably spaced equidistant from the circumference of the rotor.

[0062] In preferred embodiments of all aspects of the present invention, the pump comprises three diaphragms equidistant from the circumference of a cavity in which a rotor is located, and the rotor has two surface recesses that, together with the inner surface of the housing, form two fluid transport chambers that transport fluid from a first fluid port to a second fluid port as the rotor rotates.

[0063] If the rotor is twisted, the pump may include an equal number of elastically deformable diaphragms and surface depressions on the rotor. In a preferred embodiment of the pump according to a second or third aspect of the present invention, the pump includes two surface depressions on the rotor and two elastically deformable diaphragms.

[0064] In all aspects of the present invention, all inner surfaces of the pump can be sterilized using a gas such as ethylene oxide or vaporized hydrogen peroxide.

[0065] According to all aspects of the present invention, the first fluid port and the second fluid port can be located in various positions relative to each other, provided that the first fluid port is in fluid flow communication with the first end of the rotor and the second fluid port is in fluid flow communication with the second end of the rotor. For example, both the first and second fluid ports may be axially aligned with the longitudinal axis of rotation of the rotor, or both the first and second fluid ports may be radially aligned with the longitudinal axis of rotation of the rotor, or one of the first and second fluid ports may be axially aligned with the longitudinal axis of rotation of the rotor and the other of the first and second fluid ports may be radially aligned with the longitudinal axis of rotation of the rotor.

[0066] In one embodiment of all aspects of the present invention, the first and second fluid ports are located at opposite ends of the rotor. In alternative embodiments of all aspects of the present invention, the first and second fluid ports may be located within the region of the same end of the rotor, provided that the fluid flows from the second chamber through the diaphragm chamber to the second fluid outlet. In alternative embodiments of all aspects of the present invention, the first and second fluid ports are located within the region of the opposite end of the rotor.

[0067] When both the first and second fluid ports are radially aligned with respect to the longitudinal axis of rotation of the rotor, the first and second fluid ports may be located on the same side of the rotor, or alternatively, the first and second fluid ports may be circumferentially spaced apart around the circumference of the rotor.

[0068] In preferred embodiments of all aspects of the present invention, the direction of rotation of the rotor is reversible. In the first direction, the first fluid port is a fluid inlet port, and the second fluid port is a fluid outlet port. In the opposite direction, the first fluid port is a fluid outlet port, and the second fluid port is a fluid inlet port.

[0069] When the pump according to all aspects of the present invention is in operation, fluid flows into the pump through a first fluid port and into the first rotor cavity through an opening at the first end of the rotor. From the first rotor cavity, the fluid passes into the fluid transport chamber through a first opening between the first rotor cavity and a surface recess. A resilient diaphragm is pressed onto the surface of the rotor by a pressurizing means, displacing the fluid from the fluid transport chamber into the second rotor cavity through a second opening between the surface recess and the second rotor cavity.

[0070] From the second rotor cavity, the fluid flows into the second fluid port. The present invention provides, for example, the following: (Item 1) It is a pump, A first fluid port and a second fluid port, A housing having an inner surface that defines the cavity in which the rotor is located, A rotor, the rotor being rotatably mounted within the housing and having a longitudinal axis of rotation, comprising a housing engagement surface area which forms a sealing interlock with the inner surface of the housing, and a surface recess which, in accordance with the rotation of the rotor, forms a fluid transport chamber together with the inner surface of the housing for transporting fluid from the first fluid port to the second fluid port, A plurality of elastically deformable diaphragms, each of which provides a portion of the inner surface of the housing, each diaphragm comprising a rotor engagement surface and a rear surface opposite to the rotor engagement surface, the rotor engagement surface of each diaphragm being pressed to contact the rotor by the action of a pressurizing means acting on the rear surface of the diaphragm, and the number of elastically deformable diaphragms exceeding the number of surface depressions on the rotor. Equipped with, The rotor comprises an extendable body and a drive shaft, the body being substantially hollow and comprising separate first and second rotor cavities, the first rotor cavity having an opening at the first end of the rotor, the second rotor cavity having an opening at the second end of the rotor, and the rotor body further comprising a first opening between the first rotor cavity and the surface recess, and a second opening between the surface recess and the second rotor cavity. The pump is arranged such that, when the rotor body is located within the housing cavity, the first fluid port communicates with the first rotor cavity through the opening at the first end of the rotor, and the second fluid port communicates with the second rotor cavity through the opening at the second end of the rotor. The pump is such that, as the rotor rotates, at least one of the elastically deformable diaphragms is always positioned to bisect the first opening and the second opening on a recess in the rotor surface. (Item 2) The pump according to item 1, comprising a plurality of surface recesses that together form a corresponding number of fluid transport chambers with the inner surface of the housing. (Item 3) The pump according to item 1 or 2, wherein the rotor is twisted about its longitudinal axis of rotation such that the first end and the second end of the rotor are offset from each other by at least 10 degrees, or at least 15 degrees, or 20 degrees or less. (Item 4) The pump according to any one of the above items, wherein the housing comprises three elastically deformable diaphragms, and the rotor comprises two surface recesses that, together with the inner surface of the housing, form two fluid transport chambers. (Item 5) The pump according to any one of the above items, comprising a plurality of surface recesses, each surface recess comprising a first opening between the first rotor cavity and the surface recess and a second opening between the surface recess and the second rotor cavity. (Item 6) The pump according to any one of the above items, wherein each of the plurality of elastically deformable diaphragms is pressed to contact the rotor by a separate pressurizing means acting on the rear surface of the diaphragm. (Item 7) The pump according to any one of items 1-5, wherein each of the plurality of elastically deformable diaphragms is pressed to contact the rotor by a common pressurizing means acting on all rear surfaces of the diaphragms. (Item 8) The pump according to any one of the above items, wherein the pressurizing means comprises a spring, an elastic member, and / or a fluid acting on the rear surface of the diaphragm. (Item 9) The pump according to item 8, wherein the fluid acting on the rear surface of the diaphragm is a pressurized fluid. (Item 10) The pump according to any one of the above items, wherein one or each elastically deformable diaphragm comprises linear ribs extending longitudinally along the length of the rear surface of the diaphragm. (Item 11) The pump according to any one of items 1-9, wherein linear ribs act on the rear surface of one or each elastically deformable diaphragm that extends longitudinally along the length of the diaphragm. (Item 12) The pump according to item 10 or 11, wherein the ribs are angled at least 10 degrees, or at least 15 degrees, or at least 20 degrees with respect to the longitudinal axis of rotation of the rotor. (Item 13) The pump according to any one of items 10-12, comprising a rotor that is twisted about its longitudinal axis of rotation such that the first and second ends of the rotor are offset from each other by at least 10 degrees, wherein the rotor is twisted in the opposite direction to the angled ribs on the elastically deformable diaphragm. (Item 14) The pump according to any one of the above items, wherein the rotor comprises a substantially cylindrical body having one or more surface recesses formed thereon, and the housing engagement surface area that forms a sealing restraint fit with the inner surface of the housing constitutes the entire cylindrical surface of the rotor, excluding the one or more surface recesses on the rotor. (Item 15) The pump according to item 14, wherein the housing engagement surface area of ​​the rotor comprises cylindrical areas at each end of the rotor where no surface depressions are formed, and the cylindrical areas are connected by extensions of the rotor surface that separate the longitudinal ranges of adjacent depressions. (Item 16) The pump according to any one of the above items, wherein the first and second rotor chambers are separated from each other by a partition wall extending into the hollow interior of the rotor body. (Item 17) The pump according to any one of the above items, wherein the first opening between the first rotor cavity and the surface recess and the second opening between the surface recess and the second rotor cavity are each provided by a slot in the rotor body. (Item 18) The pump according to any one of the above items, wherein the first opening between the first rotor cavity and the surface recess is located adjacent to, preferably continuously with, the edge of the recess which will form the leading edge of the recess as the rotor rotates, and the second opening between the surface recess and the second rotor chamber is located adjacent to, preferably continuously with, the opposite edge of the recess which will form the trailing edge of the recess as the rotor rotates in the direction described above. (Item 19) The pump according to any one of the above items, wherein the first opening between the first rotor cavity and the surface recess extends substantially along the entire axial length of the surface recess that sits on the first rotor cavity, and the second opening between the surface recess and the second rotor cavity extends substantially along the entire axial length of the surface recess that sits on the second rotor cavity. (Item 20) The pump according to item 19, wherein the first opening between the first rotor cavity and the surface recess extends along the entire axial length of the surface recess that sits on the first rotor cavity and continues through the first end of the rotor, and / or the second opening between the surface recess and the second rotor cavity extends along the entire axial length of the surface recess that sits on the second rotor cavity and continues through the second end of the rotor. (Item 21) The pump according to item 20, wherein the first opening and / or the second opening are tapered and open outward to the widest portion as the opening passes through the end of the rotor. (Item 22) The pump according to any one of the above items, wherein the rotor comprises a first groove and a second groove in the surface of the rotor extending substantially along the entire length of the opposing longitudinal edges of the surface recess, the first opening between the first rotor cavity and the surface recess extending along a portion of the first groove that rests on the first rotor cavity, and the second opening between the surface recess and the second rotor cavity extending along a portion of the second groove that rests on the second rotor cavity. (Item 23) It is a pump, A first fluid port and a second fluid port, A housing having an inner surface that defines the cavity in which the rotor is located, A rotor, the rotor being rotatably mounted within the housing and having a longitudinal axis of rotation, comprising a housing engagement surface area which forms a sealing interlock with the inner surface of the housing, and a surface recess which, in accordance with the rotation of the rotor, forms a fluid transport chamber with the inner surface of the housing for transporting fluid from the first fluid port to the second fluid port, wherein the rotor is twisted about its longitudinal axis of rotation such that the first and second ends of the rotor are offset from each other by at least 10 degrees, A resilient diaphragm providing a portion of the inner surface of the housing, wherein the diaphragm comprises a rotor engagement surface and a rear surface opposite to the rotor engagement surface, and the rotor engagement surface of the diaphragm is pressed to contact the rotor by the action of a pressurizing means acting on the rear surface of the diaphragm, and Equipped with, The rotor comprises an extendable body and a drive shaft, the body being substantially hollow and comprising separate first and second rotor cavities, the first rotor cavity having an opening at the first end of the rotor, the second rotor cavity having an opening at the second end of the rotor, and the rotor body further comprising a first opening between the first rotor cavity and the surface recess, and a second opening between the surface recess and the second rotor cavity. The pump is arranged such that, when the rotor body is located within the housing cavity, the first fluid port communicates with the first rotor cavity through the opening at the first end of the rotor, and the second fluid port communicates with the second rotor cavity through the opening at the second end of the rotor. The pump is such that, as the rotor rotates, the elastically deformable diaphragm is always arranged to bisect the first opening and the second opening on the rotor surface recess. (Item 24) It is a pump, A first fluid port and a second fluid port, A housing having an inner surface that defines the cavity in which the rotor is located, A rotor, the rotor being rotatably mounted within the housing and having a longitudinal axis of rotation, comprising a housing engagement surface area which forms a sealing interlock with the inner surface of the housing, and a surface recess which, in accordance with the rotation of the rotor, forms a fluid transport chamber together with the inner surface of the housing for transporting fluid from the first fluid port to the second fluid port, A resilient diaphragm providing a portion of the inner surface of the housing, the diaphragm comprising a rotor engagement surface and a rear surface opposite to the rotor engagement surface, wherein the rotor engagement surface of the diaphragm is pressed to contact the rotor by the action of a pressurizing means acting on the rear surface of the diaphragm, and linear ribs either stand upright from the rear surface of the resilient diaphragm or act on the rear surface of the diaphragm, the linear ribs being angled at least 10 degrees with respect to the longitudinal axis of rotation of the rotor, and Equipped with, The rotor comprises an extendable body and a drive shaft, the body being substantially hollow and comprising separate first and second rotor cavities, the first rotor cavity having an opening at the first end of the rotor, the second rotor cavity having an opening at the second end of the rotor, and the rotor body further comprising a first opening between the first rotor cavity and the surface recess, and a second opening between the surface recess and the second rotor cavity. The pump is arranged such that, when the rotor body is located within the housing cavity, the first fluid port communicates with the first rotor cavity through the opening at the first end of the rotor, and the second fluid port communicates with the second rotor cavity through the opening at the second end of the rotor. The pump is such that, as the rotor rotates, the elastically deformable diaphragm is always arranged to bisect the first opening and the second opening on the rotor surface recess. (Item 25) The pump according to item 24, wherein the rotor is twisted about its longitudinal axis of rotation such that the first and second ends of the rotor are offset from each other by at least 10 degrees, and the rotor is twisted in the opposite direction to the angle of the ribs. (Item 26) A pump according to any one of items 23-25, comprising multiple elastically deformable diaphragms. (Item 27) A pump according to any one of items 23-26, comprising a rotor having a plurality of surface recesses that together form a corresponding number of fluid transport chambers with the inner surface of the housing. (Item 28) A pump according to any one of items 23-27, comprising an equal number of elastically deformable diaphragms and surface depressions on the rotor. [Brief explanation of the drawing]

[0071] The following is a more detailed description of embodiments of the present invention, provided only as examples, with reference to the accompanying drawings.

[0072] [Figure 1] Figure 1 shows a schematic partial cut of a rotor according to one of the first or third embodiments of the present invention. [Figure 2] Figure 2 shows a rotor according to one of the first or third embodiments of the present invention, illustrating fluid flow. [Figure 3] Figure 3 is a schematic cross-sectional view through a portion of the pump, which includes the rotors shown in Figures 1 and 2. [Figure 4] Figure 4 is a schematic partial cross-section of a pump according to a second embodiment of the first or third aspect of the present invention. [Figure 5] Figure 5 is a cross-sectional view of the pump shown in Figure 4. [Figure 6] Figure 6 is a schematic diagram of a rotor according to a second embodiment of the present invention. [Figure 7]Figure 7 is a schematic illustration of a rotor according to a second embodiment of a second aspect of the present invention. [Figure 8] Figure 8 is a schematic illustration of a rotor according to a third embodiment of the second aspect of the present invention. [Figure 9] Figure 9 is a schematic partial cross-section of a part of a pump according to an embodiment of a third aspect of the present invention. [Figure 10] Figure 10 is a schematic partial cross-section illustration of a portion of a pump according to an alternative embodiment of a third aspect of the present invention. [Figure 11] Figure 11 is a schematic cross-sectional view of a pump according to one embodiment of the first aspect of the present invention. [Figure 12] Figure 12 is a schematic diagram of a rotor according to an alternative embodiment of the first or third aspect of the present invention. [Figure 13] Figure 13 is a schematic partial cross-section of the rotor shown in Figure 12. [Modes for carrying out the invention]

[0073] Figure 1 shows that the rotor 10 has a substantially cylindrical shape. The rotor 10 has two surface recesses 20 that extend along the longitudinal range of the rotor 10, substantially parallel to the longitudinal rotation axis 15 of the rotor. The surface recesses 20 are provided by concave sections of the rotor. At each end of the rotor, the rotor has housing engagement surface areas 25 between adjacent surface recesses 20.

[0074] The rotor is hollow and comprises a first rotor cavity 30 and a second rotor cavity 35, which are arranged continuously within the rotor 10. The rotor includes a drive shaft 40 that extends within the hollow interior of the rotor 10 and is attached thereto.

[0075] Each end 45, 50 of the rotor 10 is open to provide fluid access to the first and second fluid cavities 30, 35, respectively.

[0076] In the embodiment shown in Figure 1, the rotor 10 further includes a first groove 52 and a second groove 53 that extend along the opposing longitudinal edges of the surface recess 20.

[0077] Slots 55 and 60 provide openings between the first rotor cavity 30 and the surface recess 20, and between the second rotor cavity 35 and the surface recess 20, respectively. Each slot 55, 60 is essentially linear, extends along the longitudinal edge of the recess 20, and is essentially parallel to the longitudinal axis of rotation 15 of the rotor. However, the slot 55 providing the first opening is located within the first groove 52, and the slot 60 providing the second opening is located within the second groove 53. Slots 55 and 60 are parallel but adjacent to opposite sides of the land 25 extending between the recesses 20. For each of the two surface recesses 20 in the embodiment shown in Figure 1, there is a slot 55 providing a first opening between the first rotor cavity 30 and the surface recess 20, and a slot 60 providing a second opening between the second rotor cavity 35 and the surface recess 20. Slots 55 and 60 are located on opposite sides and opposite ends of the recess 20. The diagram shown in Figure 1 illustrates only one slot 55, 60 of each recess 20.

[0078] In the embodiment shown in Figure 1, both slots 55 providing an opening between the first rotor cavity 30 and the surface recess 20 allow fluid to flow from the first rotor cavity 35 into the chamber formed by each surface recess 20. Similarly, both slots 60 would allow fluid to flow from the chamber formed by each surface recess 20 into the second rotor cavity 35.

[0079] Figure 2 illustrates an alternative embodiment of the rotor of Figure 1, without grooves 52, 53 for arranging slots 55 and 60, although similar features are referred to by the same reference numerals. Figure 2 also illustrates the direction of fluid flow into the first rotor cavity 30 through an opening in the end 45 of the rotor 10, and out through the slot 55 from the first rotor cavity into the chamber (not shown) formed by the surface depressions 20, with respect to a given direction of rotation of the rotor. Figure 2 also shows fluid flowing from an adjacent chamber (not shown) formed by an adjacent surface depression 20 into the slot 60, into the second rotor cavity 35, and out through the open end 50 of the rotor 10. This fluid flow will apply equally to the embodiments of Figures 1 and 2.

[0080] Figure 3 shows a rotor 105 similar to the rotor 10 of Figures 1 and 2 within the housing 100. The cross-sectional view of Figure 3 more clearly shows the arrangement of the first rotor cavity 30 and the second rotor cavity 35. This also shows a partition wall 70 separating the first and second rotor cavities 30, 35. Figure 3 also more clearly illustrates how the drive shaft 40, which is attached to or integrated with the rotor, extends from the interior of the hollow rotor 10. Only one slot 60 is shown in this figure, which is the opening between the second rotor cavity 35 and a surface recess (not shown). This figure illustrates the housing engagement surface area 25 between adjacent surface recesses (not shown) at each end of the rotor.

[0081] Figure 3 further illustrates pairs of diaphragm chambers 150, each surrounding the rear surface of the diaphragm 120. The diaphragm is pressed into contact with the rotor 10 by a pressurizing means (not shown).

[0082] Figures 4 and 5 show a pump 200 having a housing 205, a first fluid port 210 providing a fluid inlet, and a second fluid port 215 providing a fluid outlet. The housing has an inner surface 220 defining a cavity in which a rotor 225 is located. The rotor 225 has a longitudinal axis of rotation, indicated by a dashed line 230. The rotor 225 has a surface 235 at each of its ends and lands extending between recesses on its surfaces, together providing a housing engagement surface area for the rotor. The rotor shown in Figures 4 and 5 is twisted about the longitudinal axis of rotation 230 such that the first end 240 and the second end 245 are offset from each other. The rotor 225 has two surface recesses 250 provided by a concave area on the rotor surface. An elastically deformable diaphragm 255 is formed by a thinner section of the housing that provides a cavity in which the rotor 225 is located. The elastically deformable diaphragm 255 has a rotor engagement surface 257 and a rear surface 260. A pressurizing means in the form of a spring 265 contacts the rear surface 260 of the diaphragm 255. Figures 4 and 5 show that the rotor 225 comprises an extendable body which is substantially hollow and includes a first rotor cavity 270 and a second rotor cavity (not shown). The first rotor cavity 270 has an opening at the first end 240 of the rotor, and the second rotor cavity (not shown) has an opening (not shown) at the second end 245 of the rotor. The first rotor cavity 270 and the second rotor cavity (not shown) are separated from each other by a partition wall 280 which extends across the entire interior of the hollow rotor to prevent fluid from flowing along the entire internal length of the rotor. The drive shaft 285 extends from the partition wall 280. The rotor includes a first opening 290 extending between a first rotor cavity 270 and a surface recess 250 of the rotor. As can be seen from Figure 4, the first opening 290 has a tapered shape and extends along the longitudinal edge of the section of the surface recess 250 that sits atop the first rotor cavity 270, continuing across the land 235 at the first end 240 of the rotor, and creating an opening in the housing engagement surface provided by the land 235 at the first end 240 of the rotor.The rotor also includes a similarly arranged second opening (not shown) extending between a second rotor cavity (not shown) and the surface recess 250. The second opening will be located on the opposite longitudinal edge of the recess 250 and at the opposite end of the rotor 225, such that it sits atop the second rotor cavity (not shown). As can be seen particularly from Figure 4, the pressurizing means 265 presses a diaphragm 255 that is elastically deformable to contact the surface recess 250, and because the second opening (not shown) is located on the opposite longitudinal edge of the recess 250, the contact line between the diaphragm 255 and the surface recess 250 is positioned to bisect the first opening 290 and the second opening (not shown).

[0083] Three elastically deformable diaphragms 255 (not all shown) are present, spaced equidistant from the circumference of the rotor, and a spring 265, which provides a pressurizing means, acts on the rear surface of each diaphragm.

[0084] Each of the two surface recesses 250 has a first opening 290 and a second opening, both extending along the opposite longitudinal edge of each recess 250 at the opposite end of the rotor.

[0085] When the pump 200 is in use, the rotor 225 is rotated by the action of a motor connected to the drive shaft 285, causing fluid to flow into the first fluid port 210 and then into the first rotor cavity 270 through the open first end 245 of the rotor 225. From the first rotor cavity 270, the fluid flows through each first opening 290 into the fluid transport cavity provided between the surface recess 250 and the inner surface 220 of the housing. An elastically deformable diaphragm 255 is pressed to contact the surface of the rotor as it rotates by the action of a spring 265. The action of the diaphragm 255 on the surface of the rotor 225 displaces the fluid from the fluid transport cavity as the rotor rotates, causing the fluid to flow through a second opening into a second rotor cavity (not shown). From there, the fluid flows out of the pump through a second fluid port 215.

[0086] Figure 6 shows the alternative rotor 300. The rotor is twisted around the longitudinal rotation axis 315 of the rotor 300 such that the opposing ends 310 and 320 of the rotor are offset from each other.

[0087] It can be seen that the result of twisting the rotor is that the shape of the surface depressions 330, 335 is distorted. Since the first slot 340, which provides an opening between the first rotor cavity 350 and the surface depression 330, and the second slot 345, which provides an opening between the second rotor cavity 355 and the surface depression 335, extend along the opposing edges of the depressions 330, 335, the twisting of the rotor also causes the slots 340, 345 to be angled with respect to the longitudinal rotation axis 315 of the rotor 300. Figure 4 also illustrates that twisting the rotor also angles the land 360 between adjacent depressions 330, 335, which is angled with respect to the longitudinal rotation axis 315 of the rotor 300.

[0088] Figure 7 shows a rotor 400, which is a modified version of the rotor 300 of Figure 5. In this embodiment, a first slot 440 provides an opening between the first rotor cavity 450 and the surface recess 430 and continues through the first end 410 of the rotor. A second slot 445, which provides an opening between the second rotor cavity 455 and the surface recess 435, continues through the second end 420 of the rotor. It can be seen that the first slot 440 and the second slot 445 extend through the housing engagement surface area 460 at each end of the rotor.

[0089] The dashed line 465 extends across the interior of the rotor 400, illustrating the location of a partition separating the first rotor cavity 450 and the second rotor cavity 455.

[0090] The arrangement of the first and second slots is not limited to a twisted rotor as illustrated in Figures 4 and 7. In the rotors of Figures 1 and 2, the slots 55 and 60 may also extend through the first and second ends 45 and 50, respectively, and through the surface engagement area 25.

[0091] Figure 8 shows a rotor 500, which is a modified version of the rotor 400 in Figure 6. In this embodiment, the first slot 540 provides an opening between the first rotor cavity 550 and the surface recess 530. The slot is open at the first end 510 of the rotor. The second slot 545 provides an opening between the second rotor cavity 555 and the surface recess 535.

[0092] The slots are open at the second end 520 of the rotor. It can be seen that the first slot 540 and the second slot 545 extend through the housing engagement surface area 560 at each end of the rotor. In the embodiment of Figure 8, the first slot 540 and the second slot 545 are tapered, with their widest portions forming openings in the first end 510 and the second end 520 of the rotor, respectively.

[0093] The dashed line 565 illustrates the location of a partition wall that extends across the interior of the rotor 500, separating the first rotor cavity 550 and the second rotor cavity 555.

[0094] The arrangement of the first and second slots is not limited to a twisted rotor. In the rotors of Figures 1 and 2, the slots 55 and 60 may also be tapered and extend through the first and second ends 45 and 50, respectively, and through the surface engagement surface area 25.

[0095] Figure 9 shows a portion of a pump 600 having a housing 605, a first fluid port 610 providing a fluid inlet, and a second fluid port (not shown) providing a fluid outlet. The housing has an inner surface 620 that defines a cavity in which a rotor 625 is located. The rotor 625 has a longitudinal axis of rotation, indicated by a dashed line 630. The rotor 625 has lands 635 between recesses on its surface at each of its ends, together providing a housing engagement surface area for the rotor. The rotor 625 has two surface recesses 650, provided by a concave area on the rotor surface. A resilient diaphragm 655 is formed by a thinner section of the housing that provides a cavity in which the rotor 625 is located. The resilient diaphragm 655 has a rotor engagement surface 657 and a rear surface 660. The elastically deformable diaphragm 655 has linear ribs 665 protruding from the rear surface 660 of the diaphragm 655. The linear ribs 665 are angled with respect to the longitudinal rotation axis 630 of the rotor. Figure 9 shows that the rotor 625 comprises an extended body which is substantially hollow and has a first rotor cavity 670 and a second rotor cavity (not shown) at opposite ends of the rotor 625. The first rotor cavity 670 has an opening at the first end 675 of the rotor, and the second rotor cavity (not shown) has an opening (not shown) at the second end (not shown) of the rotor. The first rotor cavity 670 and the second rotor cavity (not shown) are separated from each other by partitions (not shown) that extend across the entire interior of the hollow rotor to prevent fluid from flowing along the entire internal length of the rotor. The rotor 625 includes a first opening 690 extending between a first rotor cavity 670 and a surface recess 650 of the rotor. The first opening 690 has a linear shape and extends along the longitudinal edge of the section of the surface recess 650 that sits atop the first rotor cavity 670. The rotor also includes a similarly arranged second opening (not shown) extending between a second rotor cavity (not shown) and the surface recess 650. The second opening is located on the opposite longitudinal edge of the recess 650 and at the opposite end of the rotor 625, so that it sits atop the second rotor cavity (not shown).Each surface recess 650 has a first opening 690 and a second opening, which are arranged at the opposite end of the rotor and on the opposite side of the recess.

[0096] When the pump 600 is in use, the rotor 625 is rotated by the action of a motor connected to the drive shaft 685, causing fluid to flow into the first fluid port 610 and then into the first rotor cavity 670 through the open first end 675 of the rotor 625. From the first rotor cavity 670, the fluid flows through each first opening 690 into fluid transport cavities provided between the surface recess 650 and the inner surface 620 of the housing. A resilient diaphragm 655 is pressed to contact the surface of the rotor as it rotates by the action of a pressurizing means (not shown). The action of the diaphragm 655 on the surface of the rotor 625 displaces the fluid from the fluid transport cavities as the rotor rotates, causing the fluid to flow into a second rotor cavity (not shown) through a second opening (not shown). From there, the fluid flows out of the pump through a second fluid port (not shown).

[0097] Figure 10 shows a portion of a pump 700 having a housing 705, a first fluid port 710 providing a fluid inlet, and a second fluid port (not shown) providing a fluid outlet. The housing has an inner surface 720 that defines a cavity in which a rotor 725 is located. The rotor 725 has a longitudinal axis of rotation, indicated by a dashed line 730. The rotor 725 has lands 735 between recesses on its surface at each of its ends, together providing a housing engagement surface area for the rotor. The rotor 725 has two surface recesses 750, provided by a concave area on the rotor surface. A resilient diaphragm 755 is formed by a thinner section of the housing that provides a cavity in which the rotor 725 is located. The resilient diaphragm 755 has a rotor engagement surface 757 and a rear surface 760. The elastically deformable diaphragm 755 has linear ribs 765 protruding from the rear surface 760 of the diaphragm 755. The linear ribs 765 are angled with respect to the longitudinal rotation axis 730 of the rotor. Figure 10 shows that the rotor 725 has an extended body which is substantially hollow and has a first rotor cavity 770 and a second rotor cavity (not shown) at the opposite end of the rotor 725. The rotor 725 is twisted about the longitudinal rotation axis 730 such that the opposite ends of the rotor 725 are offset from each other. The rotor 725 is twisted in the direction opposite to the direction in which the ribs 765 are angled with respect to the longitudinal rotation axis 730 of the rotor. The first rotor cavity 770 has an opening at the first end 775 of the rotor, and the second rotor cavity (not shown) has an opening (not shown) at the second end (not shown) of the rotor. The first rotor cavity 770 and the second rotor cavity (not shown) are separated from each other by partitions (not shown) that extend across the entire interior of the hollow rotor, preventing fluid from flowing along the entire interior length of the rotor. The rotor 725 includes a first opening 790 that extends between the first rotor cavity 770 and the rotor surface recess 750.The first opening 790 has a tapered shape and extends along the longitudinal edge of a section of the surface recess 750 that sits atop the first rotor cavity 770, continuing across the land 735 at the first end 775 of the rotor, and creating an opening in the housing engagement surface provided by the land 735 at the first end 775 of the rotor. The rotor also includes a similarly arranged second opening (not shown) that extends between a second rotor cavity (not shown) and the surface recess 750. The second opening is located on the opposite longitudinal edge of the recess 750 and at the opposite end of the rotor 725, so that it sits atop the second rotor cavity (not shown). Each surface recess 750 has a first opening and a second opening, which are arranged at the opposite end of the rotor and on the opposite side of the recess.

[0098] When the pump 700 is in use, the rotor 725 is rotated by the action of a motor connected to the drive shaft 785, causing fluid to flow into the first fluid port 710 and then into the first rotor cavity 770 through the open first end 775 of the rotor 725. From the first rotor cavity 770, the fluid flows through each first opening 790 into fluid transport cavities provided between the surface recesses 750 and the inner surface 720 of the housing. A resiliently deformable diaphragm 755 is pressed to contact the surface of the rotor as it rotates by the action of a pressurizing means (not shown). The action of the diaphragm 755 on the surface of the rotor 725 displaces the fluid from the fluid transport cavities as the rotor rotates, causing the fluid to flow through a second opening into a second rotor cavity (not shown). From there, the fluid flows out of the pump through a second fluid port (not shown).

[0099] Figure 11 illustrates a cross-sectional view through a portion of a pump according to one embodiment of the present invention. This figure illustrates the action of multiple diaphragms on the surface of a rotor having multiple recesses. In particular, Figure 11 shows a housing 910 comprising three elastically deformable diaphragms 920 formed integrally with the housing, each provided by a thinner section of the housing. The section of housing providing the diaphragms is thin enough to allow the diaphragms to be elastically deformable. The three diaphragms 920 are spaced equidistant from each other with respect to the circumference of the rotor 930.

[0100] The rotor 930 includes two surface recesses 940 that, together with the inner surface 945 of the housing, form two fluid transport chambers 950.

[0101] Each diaphragm 920 is pressed to contact the surface of the rotor 930 by a spring mechanism 955 located within the diaphragm chamber 960. The spring mechanism 955 ensures that each elastically deformable diaphragm 920 remains in contact with the surface of the rotor 930 as it rotates and the surface profile of the rotor 930 changes. As can be seen in Figure 11, each spring mechanism 955 includes ribs acting on the rear surface of the diaphragm 920.

[0102] Figures 12 and 13 illustrate an embodiment of a rotor 1000 having an extended body, the body being substantially hollow and comprising a first rotor cavity 1010 and a second rotor cavity 1015. The first and second rotor cavities extend longitudinally along the length of the rotor and extend at least partially parallel to each other. The first rotor cavity 1010 and the second rotor cavity 1015 are separated from each other by partition walls 1020. The partition walls are staggered and separate the first and second rotor cavities 1010 and 1015 so that they do not have direct fluid communication with each other. The rotor further comprises two recesses 1025 and 1030. Each recess comprises a first opening 1035 between the first rotor cavity 1010 and recesses 1025, 1030, and a second opening 1040 between recesses 1025 and 1030 and the second rotor cavity 1015. In Figures 13 and 14, only the second opening 1040 of recess 1030 is shown, and only the first opening 1035 of recess 1025 is shown. The first opening 1035 and the second opening 1040 within the rotor 1000 extend along the main portions of the opposing longitudinal edges of each recess 1025, 1030. However, the arrangement of the first and second openings 1035, 1040 and the partition wall 1020 is such that the first opening 1035 opens only into the first rotor cavity 1010, and the second opening 1040 opens only into the second rotor cavity 1015. It can be seen further from Figures 12 and 13 that the first rotor cavity opens only at the first end 1045 of the rotor, and the second rotor cavity 1015 opens only at the second end 1050 of the rotor.

[0103] The arrows indicate the direction of fluid flow in one direction of rotation when the rotor 1000 is used in a pump according to any aspect of the present invention. As can be seen from Figure 13, the fluid flows through the first end 1045 into the first rotor cavity 1010, and from there the fluid flows through the first opening 1035 into the depressions 1025, 1030. As the pump operates and the rotor rotates in a given direction, the fluid in the depressions 1025, 1030 is displaced by pressurizing means (not shown) through the second opening 1040 into the second rotor cavity 1015 and out through the open second end 1050 of the rotor 1000. If the direction of rotation of the rotor is reversed, the direction of fluid flow will also be reversed.

Claims

1. It is a pump, A first fluid port and a second fluid port, A housing having an inner surface defining a cavity, wherein the rotor is located within the cavity, A rotor, wherein the rotor is rotatably mounted within the housing and has a longitudinal axis of rotation, and the rotor comprises a housing engagement surface area that forms a sealing interlock with the inner surface of the housing, and a surface recess that, together with the inner surface of the housing, forms a fluid transport chamber for transporting fluid from a first fluid port to a second fluid port in response to the rotation of the rotor, A plurality of elastically deformable diaphragms, each providing a portion of the inner surface of the housing, each diaphragm comprising a rotor engagement surface and a rear surface opposite to the rotor engagement surface, the rotor engagement surface of each diaphragm being pressed to contact the rotor by a pressurizing means acting on the rear surface of the diaphragm, and the number of elastically deformable diaphragms exceeding the number of surface depressions on the rotor. Equipped with, The rotor comprises an extendable body and a drive shaft, the body being substantially hollow and comprising separate first and second rotor cavities, the first rotor cavity having an opening at the first end of the rotor, the second rotor cavity having an opening at the second end of the rotor, and the rotor further comprising a first opening between the first rotor cavity and the surface recess, and a second opening between the surface recess and the second rotor cavity. The pump is arranged such that, when the rotor is located within the cavity in the housing, the first fluid port communicates with the first rotor cavity through the opening at the first end of the rotor, and the second fluid port communicates with the second rotor cavity through the opening at the second end of the rotor. The pump is arranged such that, when the rotor rotates, at least one of the elastically deformable diaphragms always divides the first opening and the second opening in a recess on the rotor surface.

2. The pump according to claim 1, comprising a plurality of surface recesses that form a corresponding number of fluid transport chambers together with the inner surface of the housing.

3. The pump according to claim 1, wherein the rotor is twisted about its longitudinal axis of rotation such that the first end and the second end of the rotor are offset from each other by at least 10 degrees, or at least 15 degrees, or 20 degrees or less.

4. The pump according to claim 1, wherein the housing comprises three elastically deformable diaphragms, and the rotor comprises two surface recesses that, together with the inner surface of the housing, form two fluid transport chambers.

5. The pump according to claim 1, comprising a plurality of surface depressions, each surface depression comprising a first opening between the first rotor cavity and the surface depression and a second opening between the surface depression and the second rotor cavity.

6. The pump according to claim 1, wherein each of the plurality of elastically deformable diaphragms is pressed to contact the rotor by a separate pressurizing means acting on the rear surface of the diaphragm.

7. The pump according to claim 1, wherein each of the plurality of elastically deformable diaphragms is pressed to contact the rotor by a common pressurizing means acting on all of the rear surfaces of the diaphragms.

8. The pump according to claim 1, wherein the pressurizing means comprises a spring, an elastic member, and / or a fluid acting on the rear surface of the diaphragm.

9. The pump according to claim 8, wherein the fluid acting on the rear surface of the diaphragm is a pressurized fluid.

10. The pump according to claim 1, wherein one or each elastically deformable diaphragm comprises linear ribs extending longitudinally along the length of the rear surface of the diaphragm.

11. The pump according to claim 1, wherein the linear ribs act on the rear surface of one or each elastically deformable diaphragm that extends longitudinally along the length of the diaphragm.

12. The pump according to claim 10, wherein the linear rib is angled with respect to the longitudinal rotation axis of the rotor by at least 10 degrees, or at least 15 degrees, or at least 20 degrees.

13. The pump according to claim 1, comprising a rotor that is twisted about the longitudinal axis of rotation such that the first and second ends of the rotor are offset from each other by at least 10 degrees, wherein the rotor is twisted in the opposite direction to the linear ribs on the elastically deformable diaphragm.

14. The pump according to claim 1, wherein the rotor comprises a substantially cylindrical body, one or more surface recesses are formed within the substantially cylindrical body, and the housing engagement surface area that forms a sealing restraint fit with the inner surface of the housing constitutes the entire cylindrical surface of the rotor, excluding the one or more surface recesses on the rotor.

15. The pump according to claim 14, wherein the housing engagement surface area of ​​the rotor comprises cylindrical areas at each end of the rotor, no surface depressions are formed within the cylindrical areas, and the cylindrical areas are connected by extensions of the rotor surface that separate the longitudinal ranges of adjacent depressions.

16. The pump according to claim 4, wherein the two fluid transport chambers are separated from each other by a partition wall extending into the hollow interior of the rotor.

17. The pump according to claim 1, wherein the first opening between the first rotor cavity and the surface recess and the second opening between the surface recess and the second rotor cavity are each provided by a slot in the rotor.

18. The pump according to claim 1, wherein the first opening between the first rotor cavity and the surface recess is adjacent to and continuous with the edge of the recess which will form the leading edge of the recess when the rotor rotates, and the second opening between the surface recess and the second rotor cavity is adjacent to and continuous with the opposite edge of the recess which will form the trailing edge of the recess when the rotor rotates about the longitudinal axis of rotation.

19. The pump according to claim 1, wherein the first opening between the first rotor cavity and the surface recess extends substantially along the entire axial length of the surface recess that sits on the first rotor cavity, and the second opening between the surface recess and the second rotor cavity extends substantially along the entire axial length of the surface recess that sits on the second rotor cavity.

20. The pump according to claim 19, wherein the first opening between the first rotor cavity and the surface recess extends along the entire axial length of the surface recess that is placed on the first rotor cavity and continues through at least one of the first ends of the rotor, and / or the second opening between the surface recess and the second rotor cavity extends along the entire axial length of the surface recess that is placed on the second rotor cavity and continues through the second end of the rotor.

21. The pump according to claim 20, wherein the first opening and / or the second opening is tapered and opens outward to the widest portion as the opening passes through the end of the rotor.

22. The pump according to claim 1, wherein the rotor comprises a first groove and a second groove in the surface of the rotor extending substantially along the entire length of the opposing longitudinal edges of the surface recess, the first opening between the first rotor cavity and the surface recess extending along a portion of the first groove superimposed on the first rotor cavity, and the second opening between the surface recess and the second rotor cavity extending along a portion of the second groove superimposed on the second rotor cavity.

23. It is a pump, A first fluid port and a second fluid port, A housing having an inner surface defining a cavity, wherein the rotor is located within the cavity, A rotor, wherein the rotor is rotatably mounted within the housing and has a longitudinal axis of rotation, and the rotor comprises a housing engagement surface area that forms a sealing interlock with the inner surface of the housing, and a surface recess that, together with the inner surface of the housing, forms a fluid transport chamber for transporting fluid from a first fluid port to a second fluid port in response to the rotation of the rotor, and the rotor is twisted about its longitudinal axis of rotation such that the first and second ends of the rotor are offset from each other by at least 10 degrees, A resilient diaphragm providing a portion of the inner surface of the housing, wherein the diaphragm comprises a rotor engagement surface and a rear surface opposite to the rotor engagement surface, and the rotor engagement surface of the diaphragm is pressed to contact the rotor by a pressurizing means acting on the rear surface of the diaphragm, and Equipped with, The rotor comprises an extendable body and a drive shaft, the body being substantially hollow and comprising separate first and second rotor cavities, the first rotor cavity having an opening at the first end of the rotor, the second rotor cavity having an opening at the second end of the rotor, and the rotor further comprising a first opening between the first rotor cavity and the surface recess, and a second opening between the surface recess and the second rotor cavity. The pump is arranged such that, when the rotor is located within the cavity in the housing, the first fluid port communicates with the first rotor cavity through the opening at the first end of the rotor, and the second fluid port communicates with the second rotor cavity through the opening at the second end of the rotor. The pump is arranged such that, when the rotor rotates, the elastically deformable diaphragm always divides the first opening and the second opening on the rotor surface recess.

24. It is a pump, A first fluid port and a second fluid port, A housing having an inner surface defining a cavity, wherein the rotor is located within the cavity, A rotor, wherein the rotor is rotatably mounted within the housing and has a longitudinal axis of rotation, and the rotor comprises a housing engagement surface area that forms a sealing interlock with the inner surface of the housing, and a surface recess that, together with the inner surface of the housing, forms a fluid transport chamber for transporting fluid from a first fluid port to a second fluid port in response to the rotation of the rotor, A resilient diaphragm providing a portion of the inner surface of the housing, the diaphragm comprising a rotor engagement surface and a rear surface opposite to the rotor engagement surface, wherein the rotor engagement surface of the diaphragm is pressed to contact the rotor by a pressurizing means acting on the rear surface of the diaphragm, and linear ribs either stand upright from the rear surface of the resilient diaphragm or act on the rear surface of the diaphragm, the linear ribs being angled at least 10 degrees with respect to the longitudinal axis of rotation of the rotor, and Equipped with, The rotor comprises an extendable body and a drive shaft, the body being substantially hollow and comprising separate first and second rotor cavities, the first rotor cavity having an opening at the first end of the rotor, the second rotor cavity having an opening at the second end of the rotor, and the rotor further comprising a first opening between the first rotor cavity and the surface recess, and a second opening between the surface recess and the second rotor cavity. The pump is arranged such that, when the rotor is located within the cavity in the housing, the first fluid port communicates with the first rotor cavity through the opening at the first end of the rotor, and the second fluid port communicates with the second rotor cavity through the opening at the second end of the rotor. The pump is arranged such that, when the rotor rotates, the elastically deformable diaphragm always divides the first opening and the second opening on the rotor surface recess.

25. The pump according to claim 24, wherein the rotor is twisted about its longitudinal axis of rotation such that the first and second ends of the rotor are offset from each other by at least 10 degrees, and the rotor is twisted in the opposite direction to the angle of the ribs.

26. The pump according to claim 24, comprising a plurality of elastically deformable diaphragms.

27. The pump according to claim 24, comprising a rotor having a plurality of surface recesses that together form a corresponding number of fluid transport chambers with the inner surface of the housing.

28. The pump according to claim 24, comprising an equal number of elastically deformable diaphragms and surface depressions on the rotor.

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