Fluid delivery device

Abstract

A fluid delivery device includes a peristaltic pump assembly having a pump head and a drive mechanism. The pump head comprises a pump head housing and a plurality of compression elements movable within the pump head housing. The drive mechanism is operable to exert a driving force on the compression elements to move the compression elements within the pump head housing. The pump head housing is configured to receive a portion of a flexible tube extending between an arcuate inner surface of the pump head housing and the compression elements, such that the driven movement of the compression elements peristaltically compresses the flexible tube against the arcuate inner surface to drive a fluid within the tube in the direction of movement of the compression elements.

Description

"Fluid delivery device"Technical Field

[0001] The present disclosure relates to fluid delivery devices including positive displacement pumps. More particularly, the present disclosure relates to a rotary peristaltic pump suitable for use in medical applications, such as for delivering a medical fluid to a patient.Background

[0002] Pumps are widely used in various applications for controlled delivery of fluids. In medical applications, pumps may be used for delivery of fluids (such as a fluid medication) to a patient.

[0003] Peristaltic pumps are positive displacement pumps, which generate pressure by movement of a constriction along a tube, similar to biological peristalsis. For example, peristaltic pumps may operate by applying compression to a length of flexible tube in order to displace the fluid contained therein through the tube. Peristaltic pumps may be particularly suited to medical applications, where it is desirable to isolate the pumped fluid from the pump components and / or from other fluids.

[0004] Rotary peristaltic pumps typically employ one or more compression elements mounted within a pump housing and driven by a motor to revolve within the pump housing. The compression elements apply compression to a segment of tube to displace the fluid within the tube in the direction of rotation.

[0005] Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the field relevant to the present disclosure as it existed before the priority date of each of the appended claims.Summary

[0006] Embodiments of the present disclosure provide a peristaltic pump assembly and a fluid delivery device including one or more peristaltic pump assemblies. Also provided is a torque transmission coupling for use in the peristaltic pump assembly.

[0007] According to one aspect of the present disclosure, there is provided a peristaltic pump assembly comprising: a pump head comprising: a pump head housing having an arcuate inner surface; and a plurality of compression elements movable within the pump head housing; and a drive mechanism operable to exert a driving force on the compression elements to move the compression elements within the pump head housing, the drive mechanism comprising: a motor; a first drive member configured to be rotatably driven by the motor about a rotational axis, the first drive member comprising a first coupling mechanism; and a second drive member comprising a second coupling mechanism releasably connectable with the first coupling mechanism to rotationally couple the second drive member to the first drive member for conjoined rotation therewith, wherein the second drive member comprises a plurality of radially spaced connectors, wherein each connector is configured for coupling to a respective one of the compression elements; wherein each compression element is configured for coupling to a respective one of the drive shafts, wherein the pump head housing is configured to receive a portion of a flexible tube extending between the arcuate inner surface and the compression elements, such that the driven movement of the compression elements peristaltically compresses the flexible tube against the arcuate inner surface of the pump head housing, thereby to drive a fluid within the tube in the direction of movement of the compression elements.

[0008] According to one aspect of the present disclosure, there is provided a fluid delivery device including at least one peristaltic pump assembly according to the present disclosure.

[0009] The driven movement of the compression elements may follow a circular path extending about the rotational axis and concentric with the arcuate inner surface.

[0010] The peristaltic pump assembly may include a torque transfer mechanism comprising the first and second coupling mechanisms. The first and second coupling mechanisms may each comprise an array of radially spaced elongate prongs. The prongs may extend substantially parallel to the rotational axis. The prongs of the first drive member may be configured to be received in meshing engagement with the prongs of the second drive member, such that rotation of the first drive member drives the second drive member. The prongs of the first drive member may be configured to be received in interdigitating engagement with the prongs of the second drive member. In some examples, when the first and second coupling mechanisms are engaged, abutting surfaces of adjacent prongs may provide drive surfaces for torque transmission between the first and second drive members.

[0011] The prongs may have a tapered shape. Each prong may include a flank portion extending substantially parallel with the rotational axis. Each prong may include an angled tip portion. The angled tip portions of the prongs may be configured for sliding engagement during assembly of the first and second coupling mechanisms to rotationally align the first and second drive members, facilitating the interdigitating engagement of the prongs.

[0012] One of the first drive member and the second drive member may comprise a male connection feature configured to be received by a corresponding female connection feature in the other of the first drive member and the second drive member. The male connection feature may comprise a protrusion. The female connection feature may comprise a recess configured to receive the protrusion.

[0013] The pump head may comprise a central spindle. The central spindle may be positioned between and in contact with the compression elements. The central spindle may be positioned centrally relative to the compression elements. The compression elements may revolve around the central spindle.

[0014] The fluid delivery device may comprise a first module and a second module connectable to the first module. The first module may comprises the motor and the first drive member. The second module may comprise the second drive member, the pump head housing and the plurality of compression elements. The second module may be configured for sterilisation prior to connection with the first module.

[0015] The fluid delivery device may comprise a controller configured to control operation of the motor. The controller may be located in the first module.

[0016] The fluid delivery may comprise a tamper evident mechanism configured to detect disconnection of the first module from the second module. The tamper evident mechanism may be configured to deactivate the device upon disconnection of the first module from the second module.

[0017] The fluid delivery device may comprise at least one flexible tube. The fluid delivery device may comprise an occlusion detection mechanism for detecting an occlusion of the flexible tube during operation of the fluid delivery device. The occlusion detection mechanism may comprise a sensor configured to detect expansion of an expandable member (for example, a balloon) in fluid communication with the flexible tube in response to an increase in pressure within the flexible tube.

[0018] The fluid delivery device may include first and second peristaltic pump assemblies according to the present disclosure. The fluid delivery device may include a pair of flexible tubes. The fluid delivery device may be operable for delivery of a first fluid and a second fluid. The first and second peristaltic pump assemblies may be provided in a symmetrically mirrored arrangement. The motors of the first and second peristaltic pump assemblies may be driven in rotationally opposite directions. Therespective compression elements of the first and second peristaltic pump assemblies may be driven in rotationally opposite directions.

[0019] The respective motors of the first and second peristaltic pump assemblies may be encoded to provide identical rotational output. The respective motors of the first and second peristaltic pump assemblies may be encoded to provide different rotational output. In some examples, the fluid delivery device may be configured such that, in operation, one peristaltic pump assembly may be active while the other peristaltic pump assembly is dormant.

[0020] According to a second aspect of the present disclosure, there is provided a torque transfer mechanism, comprising: a first drive member comprising a first coupling mechanism; and a second drive member comprising a second coupling mechanism releasably connectable with the first coupling mechanism to rotationally couple the second drive member to the first drive member for conjoined rotation therewith, wherein the first and second coupling mechanisms may each comprise an array of radially spaced elongate prongs extending substantially parallel to the rotational axis, and configured to be received in interdigitating engagement with each other,. In some examples, when the first and second coupling mechanisms are engaged, abutting surfaces of adjacent prongs may provide drive surfaces for torque transmission between the first and second drive members, wherein when the first and second coupling mechanisms are engaged, abutting surfaces of adjacent prongs may provide drive surfaces for torque transmission between the first and second drive members.

[0021] The prongs may have a tapered shape. Each prong may include a flank portion extending substantially parallel with the rotational axis. The flank portions may be configured to provide the drive surfaces for torque transmission. Each prong may include an angled tip portion. The angled tip portions of the prongs may be configured for sliding engagement during assembly of the first and second coupling mechanisms to rotationally align the first and second drive members, facilitating the interdigitating engagement of the prongs.

[0022] Throughout this specification the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or stepsBrief Description of Drawings

[0023] Embodiments will now be described by way of example only with reference to the accompanying drawings in which:

[0024] Figure 1 is a partial perspective view of a fluid delivery device according to one embodiment of the present disclosure, shown with a first module connected to a second module;

[0025] Figure 2 is a partial exploded front view of the fluid delivery device of Figure 1;

[0026] Figure 3 is a partial perspective view the second module of the fluid delivery device of Figure 1 ;

[0027] Figure 4 is a partial perspective view of the second module of the fluid delivery device of Figure 1, shown with a second module housing removed and a pump head housing removed;

[0028] Figure 5 is a top view of the second module of the fluid delivery device of Figure 1, shown with the flexible tubes, the second module housing and a pump head housing removed;

[0029] Figure 6 is a cross-sectional view of the second module of the fluid delivery device of Figure 1, taken along line 6-6 of Figure 5;

[0030] Figure 7 is a partial perspective view of a first pump head of the fluid delivery device of Figure 1, shown with a pump head housing removed;

[0031] Figure 8 is a cross-section view of the first pump head of the fluid delivery device of Figure 1 ;

[0032] Figure 9 is a perspective view of the pump head of Figure 7, shown engaged with the flexible tube;

[0033] Figure 10 is a perspective view of a torque transmission coupling of the fluid delivery device of Figure 1, including a first drive member and a second drive member shown in a decoupled configuration;

[0034] Figure 11 is a perspective view of the torque transmission coupling shown in Figure 10, showing the first drive member and the second drive member in a coupled configuration;

[0035] Figure 12 is a bottom view of the second drive member of Figure 10;

[0036] Figure 13 is a front view of the second drive member of Figure 10;

[0037] Figure 14 is a top view of the first drive member of Figure 10;

[0038] Figure 15 is a front view of the first drive member of Figure 10;

[0039] Figure 16 is a partial perspective view of a first module of the fluid delivery device shown in Figure 1, including a detail call out showing an occlusion detection mechanism;

[0040] Figure 17 is a top view of the fluid delivery device of Figure 1, shown with the second module housing removed;

[0041] Figure 18 is a cross-sectional view of the fluid delivery device of Figure 1, taken along line 18-18 of Figure 17, including a detail call-out showing the occlusion mechanism;

[0042] Figure 19 is a perspective view of the first module of the fluid delivery device of Figure 1;

[0043] Figure 20 is a perspective view of the first module of the fluid delivery device of Figure 1, shown with first drive members removed;

[0044] Figure 21 is a perspective view of the first module of the fluid delivery device of Figure 1, shown with a first module housing removed;

[0045] Figure 22 is a perspective view of selected internal components of the fluid delivery device of Figure 1, including a detail call out showing light pipes;

[0046] Figure 23 is a perspective view of the fluid delivery device of Figure 1, shown with the first module housing removed, including a detail call out showing a lightreceiving end of the light pipes;

[0047] Figure 24 is a perspective exploded view of the fluid delivery device of Figure 1, including a detail call out showing LEDs and a USB port;

[0048] Figure 25 is a perspective view of the fluid delivery device of Figure 1, shown with the first module housing removed, including a detail call-out showing a tamper evident mechanism;

[0049] Figure 26 is a bottom perspective view of the fluid delivery device of Figure 1 ;

[0050] Figure 27 is a bottom perspective view of the fluid delivery device of Figure 1, shown with the first module housing removed, including a detail call-out showing a reset button;

[0051] Figure 28 is a front view of the fluid delivery device of Figure 1 ;

[0052] Figure 29 is a cross-sectional view of the fluid delivery device of Figure 1, taken along line 29-29 of Figure 28, including a detail call-out showing a side button.Description of Embodiments

[0053] In the drawings, reference numeral 10 generally designates a fluid delivery device according to the present disclosure.

[0054] In some examples, the fluid delivery device 10 may be configured as a medicament delivery device, for delivery of one or more liquid medicaments to a patient. The term “medicament” as used herein refers to a substance, for example a drug, suitable for delivery into a patient’s body, for example to treat a condition or disease, or to provide pain relief. The medicament may include an active pharmaceutical ingredient and an excipient or formulation buffer. In some examples, the medicament may comprise an anaesthetic.

[0055] As best shown in the exploded view of Figure 2, the fluid delivery device 10 includes at least one peristaltic pump assembly 20. The peristaltic pump assembly 20 includes a pump head 100 and a drive mechanism 200. The pump head 100 comprises a pump head housing 110 having an arcuate inner surface 112 (for example, as indicated in the cross-sectional view of Figure 8). A plurality of compression elements 120 are movable within the pump head housing 110. The pump head housing 110 is configured to receive a portion of a flexible tube 300 such that, when assembled, the portion of the flexible tube 300 extends within the pump head housing 110 between the arcuate inner surface 112 of the pump head housing 110 and the compression elements 120.

[0056] The drive mechanism 200 is operable to exert a driving force on the compression elements 120 to move the compression elements 120 within the pump head housing 110. The drive mechanism 200 comprises a motor 210, a first drive member 220 and a second drive member 230. The first drive member 220 is configured to be rotatably driven by the motor 210 about a rotational axis. As best shown in Figures 10 and 11, the first drive member 220 comprises a first coupling mechanism 222, engagable with a corresponding second coupling mechanism 232 of the second drive member 230. The first and second coupling mechanisms 222, 232, are releasably connectable with each other to rotationally couple the first and second drive members220, 230 such that they rotate together about the rotational axis. The second drive member 230 comprises a plurality of radially spaced connectors 234 (for example, as shown in Figures 10 and 11). Each of the connectors 234 is configured to couple with a respective one of the compression elements 120 to drive the movement of the compression elements 120 within the pump head housing 110. The driven movement of the compression elements 120 peristaltically compresses the flexible tube 300 against the arcuate inner surface of the pump head housing 110, thereby to drive a fluid within the tube 300 in the direction of movement of the compression elements 120.

[0057] In the illustrated example, the fluid delivery device 10 includes first and second peristaltic pump assemblies 20 and a pair of flexible tubes 300, and is operable for delivery of a first fluid and / or a second fluid. The first and second fluids may be the same fluid or different fluids and may be delivered at the same flow rate or at different flow rates. In some examples, the fluid delivery device 10 may be operable such that one peristaltic pump assembly is active while the other peristaltic pump assembly is dormant. For example, the first and second fluids may be delivered simultaneously, sequentially or a combination of both. In other examples, the fluid delivery device 10 may include only a single pump assembly 20 and a single flexible tube 300. In some examples, a plurality of devices 10 (for example, two, three, four or more) may be used to provide fluid(s) to a single patient. The devices 10 may include a single pump assembly 20 and a single flexible tube 300, or may include first and second peristaltic pump assemblies 20 and a pair of flexible tubes 300. The devices 10 may be configured to operate in sync with each other or independently. The devices 10 may be configured to deliver the same type of fluid, or different types of fluid (e.g. different medications), at the same flow rate or at different flow rates.

[0058] Referring again to Figure 1, the fluid delivery device 10 may comprise a first module 30 and a second module 40. The first module 30 and the second module 40 may be connectable to each other to form the fluid delivery device 10. Figure 1 shows the device 10 with the first module 30 connected to the second module 40. The first module 30 may comprise the motor 210 and the first drive member 220, while the second module 40 may comprise the pump head 200 and the second drive member 230.

[0059] The fluid delivery device 10 comprises a housing 11 configured to at least partially enclose the at least one peristaltic pump assembly 20. The housing 11 may be at least partially defined by respective housings of the first and second modules 30, 40. In the example shown in Figure 1, the first module 30 comprises a first module housing 31. Similarly, the second module 40 comprises a second module housing 41. The first and second module housings 31, 41 may be configured as a pair of shell portions, connectable with each other to form the fluid delivery device housing 11. When assembled, the housing 11 may define a substantially fluid-tight enclosure for inhibiting fluid ingress into the device housing 11. In some examples, the device may include one or more sealing members for inhibiting fluid ingress into the housing 11.

[0060] The first module 30 may comprise a first chassis 32. The first chassis 32 may be configured for connection with the first module housing 31. The first chassis 32 may be configured to support one or more components of the first module 30, including the motor 210 and the first drive member 220. The chassis 32 may be configured to be at least partially received within the first housing 31. For example, the first chassis 32 may be configured to nest within the first housing 31.

[0061] Similarly, the second module 40 may comprise a second chassis 42. The second chassis 34 may be configured for connection with the second module housing 41. The second chassis may be configured to support one or more components of the second module 40, including the pump head 100 and the second drive member 230. The second chassis 42 may be configured to be at least partially received within the second housing 41. For example, the second chassis 42 may be configured to nest within the second housing 41. In some examples, a portion of the second chassis 42 cooperates with the first and second housings 31, 41 to form the device housing 11. The housings 31, 41 and the chassis 32, 42 may be formed from a plastics material such as Acrylonitrile Butadiene Styrene (ABS) or other suitable material.

[0062] The flexible tube 300 extends from the device housing 11, for example from the second module 40. In the illustrated example, first and second portions 302, 304 of the flexible tube 300 extend from the housing 11. The first portion 302 of the flexibletube 300 may be upstream of the pump head 100 and configured for connection to a fluid source. In the illustrated example, the flexible tube 300 is configured for connection with a fluid source remote from the device 10. In other examples, a fluid source may be integrated with the fluid delivery device 10. The second portion 304 of the flexible tube 300 may be downstream of the pump head 100 and configured for delivering the pumped fluid. For example, the flexible tube 300 may comprise a catheter, wherein the second end 304 of the flexible tube 300 may be configured for delivering fluid to a subject, either directly or in connection with an additional fluid delivery structure (such as a via connection to a separate catheter, or fluid infusion device).

[0063] One or both of the first and second modules 30, 40 may be configured for sterilisation. In the illustrated example, the second module is configured for sterilisation by exposure to a sterilising gas such as ethylene oxide (EtO). Other suitable sterilisation methods may be used. As shown in Figure 4, the second chassis 41 defines several apertures 45 configured to permit flow of a sterilising gas through the chassis 42 and into the second module housing 41.

[0064] As the components of the first module 30 do not come into contact with the flexible tube 300, there is a reduced need for these components to be sterile. The first module 30 may therefore be configured to include components which may be damaged during a sterilisation process, such as electronic components.

[0065] The device 10 may include a latching mechanism for connecting and locking the first module 30 to the second module 40. As shown in Figure 4, in the illustrated example, the locking mechanism includes a pair of opposed latch portions 43 on opposite sides of the second module 40, for example on the second chassis 43. The latch portions 43 are each receivable in a respective catch 33 in the first module 30, for example on either side of the first chassis 32 (for example, see catch 33 indicated in Figure 21). The first module 30 may be connectable to the second module 40 by bringing each latch portion 43 and corresponding catch 33 into engagement. In some examples, the latch portions 43 and the catches 33 may be configured for snap-engagement. The latch portions 43 and the catches 33 may be configured to inhibit disengagement of the first module 30 from the second module 40 once connected. In some examples, the connection between the latch portions 43 and the catches 33 may be configured to be releasable, for example by using a tool to release the latch portion 43 from the catch 33.

[0066] The second module 40, is shown in more detail in Figures 3-5. Figure 3 shows one of the pump head 100 with the pump head housing 110 in place, and the other pump head 100 with the pump head housing 110 removed. Each of the pump heads 100 is mounted on and supported by the second module chassis 42.

[0067] The pump head 100 includes the compression elements 120 and the pump head housing 110. The pump head housing 110 may be configured for connection to a base 105 of the pump head 100. The pump head base 105 may facilitate connection of the pump head 100 to the second module chassis 42. The pump head base 105 may be configured to secure the pump head housing 110. In the illustrated example, the pump head base 105 includes an annular ridge 107 configured to radially constrain the compression elements 120.

[0068] In the illustrated example, the pump head 100 further includes the second drive member 230. As best shown in Figure 6, the second drive member 230 is partially received within the pump head housing 110 and supported by the pump head base 105. The coupling mechanism 232 of the second drive member 230 extends through an opening 106 defined in the pump head base 105. As shown in Figures 4 and 6, the opening 106 in the pump head base 105 is aligned with an opening 44 in the second module chassis 42. When assembled, the second coupling mechanism 232 extends through the aligned openings 106, 44 and protrudes relative to a surface of the second module chassis 42, for example as shown in Figure 4.

[0069] The pump head 100 is shown in more detail in Figures 7 to 8. In this example, the pump head 100 includes three compression elements 120. The pump head 100 may therefore be understood as a “tri-lobular” pump head. In other examples, other numbersof compression elements 120 may be possible, such as one, two, four or more compression elements.

[0070] The second drive mechanism 230 is configured to couple to the compression elements 120 by respective connectors 234. In some examples, the compression elements 120 may be rotatably coupled to the connectors 234. In other examples, the compression elements may be fixed to the connectors 234. In the illustrated example, the connectors of the second drive mechanism 230 are in the form of elongate shafts 234, extending parallel to the rotational axis. The shafts 234 are evenly radially spaced around the rotational axis X. The compression elements are in the form of rollers 120, each having a generally cylindrical shape and including a bore 122 configured to receive a respective shaft 234, thereby to rotatably couple the rollers 120 to the second drive mechanism 230. In the illustrated example, the bore 122 is central to the roller. However, in other examples, the bore 122 may be off-centre, such that the rotation of the of the roller 120 about the shaft 134 is eccentric.

[0071] The pump head 100 may further comprise a spindle 115 positioned centrally with respect to the three compression elements 120, such that the compression elements 120 revolve around the central spindle. The central spindle 115 maintains contact with the compression elements 120 as they move within the pump head housing 110, maintaining an radially outward pressure on the compression elements 120. The spindle 115 may act as a bearing between the compression elements 120. In some examples, the central spindle 115 may be formed from a suitable bearing material for compatibility with a material of the compression elements 120. For example, the compression elements 120 may be formed from a plastics material while the central spindle 115 may be formed from stainless steel or brass.

[0072] As shown in the cross-sectional view of Figure 8, the central spindle 115 may be supported by the second drive member 230. In this example, the central spindle 115 is seated within a recess 233 in the second drive member 230, such that the central spindle 115 is axially constrained in at least one direction. The central spindle 115 may be radially constrained relative to the second drive member 230, for example in afloating arrangement. As shown in Figure 8, the recess 233 is larger than a seated portion of the central spindle 115, providing a clearance allowing for a limited amount of radial movement of the central spindle 115. In the illustrated example, the recess 233 and the seated portion of the central spindle 115 both have a circular shape in crosssection, providing for 360 degree floating movement of the central spindle 115 within the limits of the recess 233.

[0073] The second drive member 230 is configured to engage with the first drive member 220 when the first and second modules 30, 40 are connected. The first drive member 220 may be configured to be supported on the chassis 32 of the first module 30. In the illustrated example, as shown in Figures 19 and 20, the first drive member 220 is received within a recessed portion 35 in the first module chassis 32. A drive shaft 211 of the motor 210 extends through an aperture in the first module chassis 32 and into the recessed portion 35. The first drive member 220 is configured to be rotationally coupled to the drive shaft. For example, the drive shaft 211 may have a non- circular cross-sectional profile and receivable in a correspondingly shaped bore in the first drive member 220.

[0074] As discussed above, the second coupling mechanism 232 of the second drive member 230 extends through the second module chassis 24, for example as shown in Figure 4. When the first and second modules 30, 40 are assembled, the second coupling mechanism 232 is received within the recess 35 of the first module chassis and brought into interdigitating engagement with the first coupling mechanism 222.

[0075] The first drive member 220 and the second drive member 230 couple to form a torque transmission mechanism 25 for transmitting driving force from the motor 210 to the compression elements 120. An example torque transmission mechanism 25 of the peristaltic pump assembly 20 is shown in detail in Figures 10 and 11. The torque transmission mechanism 25 is shown in a decoupled configuration in Figure 10 and in a coupled configuration in Figure 11, with the first drive member 220 coupled to the second drive member 230.

[0076] As shown in Figure 10, the first drive member 220 and the second drive member 230 comprise respective coupling mechanisms 222, 232. Each coupling mechanism comprises a respective body portion, which in the illustrated example is in the form of a plate 221, 231. A plurality of elongate prongs 240, 250 extend from the plates 221, 231, respectively. The prongs 240, 250 are spaced radially about the rotational axis X and extend substantially parallel to the rotational axis X.

[0077] The prongs 240 of the first drive member 220 are configured to be received in interdigitating engagement with the prongs 250 of the second drive member 230, as shown in Figure 11.

[0078] The first and second drive members 220, 230 are shown individually in Figures 12-13 and Figures 14-15, respectively. As best shown in Figures 12 and 14, The prongs 240, 250 of the first and second drive members 220, 230 are radially spaced about the central rotational axis X. In the illustrated example, the prongs 240, 250 are evenly radially spaced. An angle A is defined between centres of adjacent prongs 250 and an angle C is defined between centres of adjacent prongs 240. The coupling mechanisms 222, 232 may each comprise a corresponding number of prongs 240, 250, such that the angles A and C are substantially equal to each other. In the illustrated example, the coupling mechanisms 222, 232 each comprise 8 prongs 240, 250, respectively, such that prong spacing angles A and prong spacing angle C between centres of adjacent prongs 240 and 250 are about 45 degrees. In other examples, the coupling mechanisms 222, 232 may include a different number of prongs 240, 250, such as 2, 3, 4, 5, 6, 7, 9, 10, 11, 12, or more prongs 240, 250. The angles A and C may vary accordingly with the number of prongs 240, 250.

[0079] Each of the prongs 240, 250 has a width in a radial direction between a radially inner face and a radially outer face, and a thickness, perpendicular to the width, between respective side faces of the prong 240, 250. The thickness of each prong 240, 250 may taper radially inwardly toward the rotational axis X. In the illustrated example, each of the prongs 240, 250, has an identical thickness and an identical width. In other examples, the prongs 240 may have a width and / or thickness different to that of theprongs 250. The thickness and spacing of the prongs 240, 250 may be configured such that spaces defined between adjacent prongs 240 are approximately equal to the thickness of the prongs 250, and vice versa, such that the prongs 240, 250 are configured to fit snugly between each other when in the coupled configuration.

[0080] Each of the prongs 240, 250, extends substantially parallel to the rotational axis, from a root 241, 251 connected to the respective plate 221, 231 to a tip portion 242, 252. As indicated in Figures 13 and 15, the prongs 240 may have a height E while the prongs 250 may have a height F. In the illustrated example, the heights E and F are substantially equal. The heights E and F may be between about 5 mm and about 15 mm, such as less than about 6 mm, less than about 7 mm, less than about 8 mm, less than about 9 mm, less than about 10 mm, less than about 11 mm, less than about 12 mm, less than about 13 mm, less than about 14 mm, or less than about 15 mm.

[0081] The prongs 240, 250, may have a tapered shape. For example, the prongs 240, 250, may taper from the root 241, 251 toward the tip portion 242, 252. The prongs 240, 250 may taper to a point, as shown in the illustrated example. In other examples, the tip portions 242, 252 may include a flattened top land portion or a rounded tip portion.

[0082] In the illustrated example, the prongs 240, 250 each include an angled tip portion 242, 252 and a flank 245, 255.

[0083] The angled tip portion 242, 252 may be defined by one or more faces of each prong 240, 250 which are sloped relative to the rotational axis. In the illustrated example, the angled tip portions 242, 252 are defined by a pair of sloped planar faces of each prong 240, 250. The angled tip portions 242, 252 may be symmetrical. For example, the sloped planar faces of the angled tip portions 242, 252 may be mirrored about a radial plane. In other examples, the angled tip portions 242, 252 may be dissymmetrical and / or include one or more curved faces.

[0084] As shown in Figures 13 and 15 the sloped planar faces of the tip portions 242, 252 define a tip angle B and D respectively. The tip angles B and D may be identicalwith each other. In other examples, the tip angles B and D may differ from each other The tip angles B and D may be configured to correspond to the prong spacing angles A and C. In this example, the tip angles B and D are about 45 degrees. In other examples, the tip angles B and D may differ from the prong spacing angles. The tip angles B and / or D may be about 25°, about 30°, about 35°, about 40°, about 45°, about 50°, about 55°, about 60°, about 65°, about 70°, about 75°, about 80°, about 85°, or about 90°.

[0085] The angled tip portions 242, 252 may define respective ridges 243, 253. For example, as shown in Figures 13 and 15, sloped planar faces defining the angled tip portions 242, 252 intersect to form the ridges 243, 253. The ridges 243, 253 may extend in a generally radial direction. The ridges 243, 253 may be substantially orthogonal to the rotational axis, or may be otherwise angled relative to the rotational axis. In the illustrated example, as best shown in Figures 13 and 15, the ridges 253 of the prongs 250 of the second drive member 230 extend substantially orthogonal to the rotational axis X. By contrast, the ridges 243 of the prongs 240 of the second drive member 220 slope inwardly toward the rotational axis X and toward the plate 221. As such, the tip portions 252 of the prongs 240 first drive member 220 taper to a point 244 at a radially outward end of the ridge 243. In other examples, the reverse configuration is contemplated. That is the ridge 243 of the first drive member 220 may be sloped, while the ridge 253 of the second drive member 230 may extend substantially orthogonal to the rotational axis. In other examples, the ridges 243, 253 may both be sloped relative to the rotational axis.

[0086] The prongs 240, 250 may define an edge between the flanks 245, 255 and the angled tip portions 242, 252 on the side faces of the prongs 240, 250. The edges 246, 256 may be sharp, or non-rounded edges, as shown in the illustrated examples. In other examples, the edges 246, 256 may be rounded, filleted, chamfered or similar. The edges 246, 256 may extend in a generally radial direction. The edges 246, 256 may be substantially orthogonal to the rotational axis, or may be otherwise angled relative to the rotational axis. In the illustrated example, as best shown in Figures 13 and 15, the edges 246 of the prongs 240 of the first drive member 220 extend substantiallyorthogonal to the rotational axis X. By contrast, the ridges 256 of the prongs 250 of the second drive member 230 slope inwardly, toward from the rotational axis X and away from the plate 231. In other examples, the reverse configuration is contemplated. That is the edge 246 of the first drive member 220 may be sloped, while the edge 256 of the second drive member 230 may extend substantially orthogonal to the rotational axis. In other examples, the edges 246, 256 may both be sloped relative to the rotational axis.

[0087] In the illustrated example, the slope of the edges 256 of the prongs 250 is configured to correspond to the slope of the ridges 243 of the prongs 240. The edges 246 and ridges 253 are similarly corresponding in slope, being configured orthogonal to the rotational axis. As such, the angled tip portions 242, 252 are provided with correspondingly shaped surfaces.

[0088] The tapered shape of the prongs 240, 250 may be configured to accommodate for misalignment between the first and second drive members 220, 230 during assembly. The prongs 240, 250 may be configured such that respective faces of the tip portions 242, 252 engage with one another as the first and second coupling mechanisms 222, 232 are brought into engagement with one another. In particular, the faces of the respective tip portions 242, 252 may be configured to abut one another in sliding engagement during assembly of the first and second coupling mechanisms 222, 232.

[0089] The sliding engagement of the tip portions 242, 252 may produce a rotational force between the first and second drive members 220, 230, causing the first and second drive members 220, 230 to rotate relative to one another as the tip portions 242, 252 are moved axially relative to each other. This rotational movement facilitates rotational alignment of the first and second drive members 220, 230 to facilitate the interdigitating engagement of the prongs 240, 250. In particular, one or both of the first second drive members 220, 230 may be configured to rotate relative to the other of the first second drive member 220, 230 to bring the prongs 240 and / or 250 of the respective drive members into alignment 220, 230 with the spaces defined between the prongs 240 and / or 250 of the other of the first second drive member 220, 230.

[0090] The angle of the faces of the tip portions 242, 252 may be configured to provide mechanical advantage to overcome a rotational resistance of the first and or second drive members 220, 230. As the first drive member 220 is coupled to the motor, a relatively high torque may be required to rotate the first drive member 220. The connection between the second drive member 230 and the other elements of device 10 may be configured such that the second drive member 230 rotates more freely than the first drive member 220. The force produced by the sliding engagement between the tip portions 242, 252 may therefore result in rotation of the second drive member 230 into alignment with a rotational position of the first drive member 220. This may facilitate easy assembly of the first and second modules 30, 40, regardless of an initial rotational position of the first and second drive members 220, 230.

[0091] The flank portions 245, 255 may be defined by one or more faces extending substantially parallel with the rotational axis X. The flank portions 245, 255 may include a substantially planar surface. As best shown in Figures 12 and 14, in the illustrated example, the flank portions 245, 255 have faces defining planes extending radially relative to the rotational axis X. In other examples, planar faces of the flank portions 245, 255 may be angled relative to radial direction and / or the axial direction. In other examples, the flank portions 245, 255 may include curved surfaces.

[0092] The prongs 240, 250 may be configured (e.g. by the height of the prongs 240, 250 in combination with sizes and / or shapes of the angled tip portions 242, 252 and / or the flanks 245, 255) such that, when the first and second drive members 220, 230 are coupled with each other (for example, as shown in Figure 11), a portion of each flank 245 abuts a corresponding portion of the adjacent flank 255 to provide drive surfaces for torque transmission between the first and second drive members 220, 230. The prongs 240, 250 may be configured such that the abutting portions of adjacent flanks 245, 255 have a length extending in the axial direction for at least 10%, at least 20%, at least 30%, at least 40%, at least 50%, at least 60% or more of the height E and / or F of the prongs 240, 250.

[0093] The first drive member 220 and the second drive member 230 may include respective abutment surfaces, configured to abut one another to limit the interdigitating engagement between the prongs 240, 250. For example, the first drive member 220 and the second drive member 230 may include respective protrusions configured to abut one another to define an axial offset between the plates 221, 231 when in the coupled configuration. In the illustrated example, as indicated in Figure 10, the first drive member 220 includes a first post 225 configured for abutting engagement with a corresponding second post 235 on the second drive member 230. The protrusions 225,235 extend axially from respective plates 221, 231 in the same direction as the respective prongs 240, 250. The combined height of the of the first and second posts 225, 235 may be configured to be greater than either of the heights E or F of the prongs 240, 250 such that, in the coupled configuration, the prongs 240 of the first drive member 220 do not contact the plate 231 of the second drive member 230, and vice versa.

[0094] The torque transmission mechanism 25 may include a male-female coupling. In the illustrated example, the first drive member 220 comprises a male connection feature 226 and the second drive member 230 comprises a female connection feature236 (for example, as indicated in Figures 8 and 12). In the illustrated example, the male connection feature comprises a protrusion 226 and the female connection feature comprises a recess 236 configured to receive the protrusion 226. In the illustrated embodiment, the male and female connection features 226, 236 are provides on the first and second posts 225, 235, respectively. The male-female coupling may be configured for a tight fit between the male and female connection features 226, 236, to provide substantially rigid axial alignment between the first drive member 220 and the second drive member 230 when coupled. The male connection feature 226 may include a tapered and / or rounded end, facilitating easy insertion to the female connection portion 236 during assembly.

[0095] In some examples, the first and second drive members 220, 230 may each be formed from a plastics material, such as injection moulded from polyacetal. In other examples, other suitable materials may be used.

[0096] The motor 210 may be an electric motor, such as a brushed DC metal gearmotor. The motor may be a highly geared motor, configured to have a low RPM and provide high torque. In one example, the motor 210 is rated for 6V, has a gear ratio of 380: 1, a speed of 46 RPM and a torque of 6.9 kg.mm. However, other suitable motor parameters may be used. The motor 210 may be provided in connection with an encoder configured to sense the rotational output of the motor 210

[0097] In some examples, first and second peristaltic pump assemblies 20 may be provided in a symmetrically mirrored arrangement. The motors 210 of the pump assemblies 20 may be configured to run in opposed directions, such that respective compression elements 120 of the first and second peristaltic pump assemblies 20 are driven in rotationally opposite directions within the pump heads. In such examples, the upstream portions 302 of the two flexible tubes 300 may be aligned with each other. Similarly, the downstream portions 304 of the two flexible tubes 300 are aligned with each other. This may facilitate easier identification of input and output tubes for a user.

[0098] The fluid delivery device 10 may comprise one or more electronic components. In the illustrated example, an electronics assembly 400 is provided in connection with the first module 30, for example as shown in Figure 21. The electronics assembly 400 may be configured to mounted to the first module chassis 32 and at received within the first module housing 31.

[0099] The electronics assembly 400 may be provided in connection with the motor 210 to provide power to the motor 210. In the illustrated example, as best shown in Figure 21, the electronics assembly 400 includes a printed circuit board (PCB) 410. The electronics assembly 400 may comprise a controller configured to control operation of the motor 210. The motor 210 may be mounted on the PCB or otherwise connected to the PCB. Where the fluid delivery device 10 includes two pump assemblies 20, the respective motors 210 of the first and second peristaltic pump assemblies 20 may be encoded to provide identical rotational output. The controller may be configured to control a volume and / or rate of fluid delivery, based on a rotational output (e.g. numberand / or speed of revolutions) of the motor 210. The controller may be programmable, for example via a data connection port such as USB port 460 shown in Figure 24.

[0100] The device 10 may be battery operated. The device 10 may include or be configured to receive at least one battery. The battery may be comprised in or receivable in the first module 30. In some examples, the battery may be rechargeable. In such examples, the first module 30 may include a charging port (such as USB port 460, for example) accessible from the exterior of the first module housing 31. In other embodiments, the device 10 may use one or more disposable batteries. Figure 21 shows the electronics assembly 400 including a pair of battery housings 420 for receiving and connecting batteries to power the electronics assembly 400. In this example, a first and second battery housing 420 is provided for powering the first and second peristaltic pump assemblies 20, respectively. In the illustrated example, each battery housing 420 is configured to receive a pair of AA batteries. However, other battery types and configurations are also contemplated, such as AAA or otherwise. In some examples, a single battery (or group of batteries) may provide power to more than one pump assembly 20.

[0101] The device may include one or more indicators, such as visual, auditory and / or haptic indicators, for providing feedback to a user to indicate a condition or state of the device 10. The feedback may be in the form of one or more stimuli, such as visual, audible or tactile stimuli, to indicate to the user the state or condition of the device 10.

[0102] In the illustrated example, as shown in Figures 22 to 24, the device 10 includes a set of light pipes 430. The light pipes each extend from a light receiving end 431 to a light emitting end 432. Each light receiving end 431 is configured to be positioned adjacent a respective LED 432 mounted on the PCB 410. The light emitting ends 432 of the light pipes 430 may be configured to be received in corresponding apertures in the housing 11 such that light emitted from the light pipes 430 is visible to a user from outside the housing 11. The light pipes may be formed from a suitable material such as a clear polycarbonate.

[0103] As shown in Figure 23, in the illustrated example, the light pipes 430 are provided in connection with the second module 40 and configured to transmit light from the LEDs through the second module 40. The light receiving ends 431 extend from the second module 40 into the first module 30 to interface with the LEDs. For example, as shown in Figure 24, the first module chassis 32 may define an opening configured to provide access to the LEDs 435 and / or the USB port 460. In the illustrated embodiment, the first module housing 41 defines apertures 46 configured to receive the light emitting ends 431 of the light pipes 430, such that the emitted light is visible, in operation, from a top surface of the device 10. In other examples, indicator lights may be visible from a different portion of the device. The LEDs may be configured to provide different colours of light, for example red, amber and / or green, for indicating status and / or required action to a user.

[0104] The fluid delivery device 10 may include a tamper evident mechanism configured to detect disconnection of the first module 30 from the second module 40. In the illustrated example, as best shown in Figure 24, the device includes at least one tab 47 extending from the second module 40 and configured to engage a switch, such as tactile switch 445, on the PCB 410 when the first module 30 is connected to the second module 40. Upon disconnection of the first module 30 from the second module 40, the switch 445 is released. The controller may be configured to deactivate and / or disable the device to inhibit use of the device when disconnection of the first module 30 from the second module 40 is detected. In the illustrated example, two tabs 47 engage two respective switches 445. Other examples may use only one tab and switch combination, or another suitable detection mechanism may be used.

[0105] The device 10 may include a reset mechanism. In the illustrated example, the device 10 includes a reset button 480. The reset button 480 may be accessible through the first module housing 31, for example by insertion of a pin or similar item through aperture 38 in the base of the housing 31. The aperture 38 may be obscured from view in normal use of the device, such that a user is inhibited from resetting the device. For example, the aperture 38 may be obscured over by a cover, such as adhesive sticker 39. The sticker 39 may additionally provide protection against fluid ingress through theaperture 38. The cover or adhesive label may be removed or punctured to provide access to the reset button 480. For example, a surgeon or other medical professional may need to re-prime the device 10 following a change of fluid source and may need to reset the device 10.

[0106] The device 10 may include an activation mechanism, such as activation button 37 shown in Figures 28 and 29. In this example, the activation button 37 is provided in a front face of the first module housing 31. The button 37 may be formed from a flexible plastic material, such as thermoplastic polyurethane or other suitable material. Depression of the button 37 may be actuate a corresponding tactile switch on the PCB 410 to activate the device 10. The button 37 may provide a substantially fluid tight connection with the first module housing 31 to inhibit fluid ingress into the device 10, for example by a providing a tight-fitting connection and defining a tortuous interface between the button 37 and housing 31 as shown in the detail call out of Figure 29.

[0107] In some examples, the device 10 includes an occlusion detection mechanism 500. The occlusion detection mechanism may be configured for detecting an occlusion of the flexible tube 300 during operation of the fluid delivery device 10. For example, the occlusion detection mechanism 500 may include a sensor configured to detect a deformation of the flexible tube 300 in response to increased pressure within the flexible tube 300. In some examples, the occlusion detection mechanism 500 may include an expandible member in connection flexible tube 300 (or an expandible portion of the flexible tube 300). In the illustrated example, the occlusion detection mechanism 500 includes balloon 310 disposed in-line with the second portion 304 of the flexible tube 300, downstream of the peristaltic pump 100 as shown in Figure 16. The balloon 310 is supported by the second module chassis 42, as shown in the detail call-out in Figure 16.

[0108] The occlusion detection mechanism 500 further includes an occlusion switch 450 on the electronic assembly 400. The occlusion switch 450 may be provided in connection with the first module 30. The occlusion switch 450 may be a tactile switch. In the illustrated example, the occlusion detection mechanism 500 may be configuredsuch that expansion of the balloon 310 actuates the occlusion switch 450, for example by depressing button 451. The occlusion detection mechanism 500 may be configured such that the occlusion switch 450 is actuated by the balloon 310 at or above a predetermined pressure threshold, which may be indicative of a blockage in the flexible tube (for example due to kinking of the tube or otherwise). In some examples, the expansion of the balloon 310 (or other expandible member in line with the flexible tube 300) may be detected by other means, such as by an optical sensor or pressure sensor. The controller may be configured to activate one or more indicators, such as an indicator light, to indicate to the user that an occlusion has been detected. Additionally or alternatively, the controller may be configured to deactivate the fluid delivery device 10 in response to actuation of the occlusion switch 450.

[0109] The above occlusion detection mechanism 500 is one non limiting example only. It is envisaged that other means of determining if an occlusion has occurred may be employed. In some examples, the occlusion detection mechanism 500 may include one or more pressure sensors configured to detect fluid pressure in the flexible tube 300. The occlusion detection mechanism 500 may be configured to actuate the occlusion switch 450 based on a change in detected pressure in the flexible tube 300. For example, the occlusion detection mechanism 500 may actuate the occlusion switch 450 based on detection of an increase in pressure above a predetermined pressure threshold, which may be indicative of resistance or blockage in the tube. In some examples, the occlusion detection mechanism 500 may be configured to actuate the occlusion switch 450 based on detection of a decrease in pressure below a predetermined pressure threshold, which may be indicative of resistance or blockage in the tube (for example a blockage in the pump or upstream of the pump). In some examples, the occlusion detection mechanism 500 may include one or more flow sensors configured to detect a flow rate within the flexible tube 300. The occlusion detection mechanism 500 may be configured to actuate the occlusion switch 450 based on a change in flow rate of the fluid in the flexible tube 300. For example, the occlusion detection mechanism 500 may actuate the occlusion switch 450 based on detection of a flow rate below a predetermined minimum flow rate threshold while the peristaltic pump is operating, which may indicate that the tube is occluded. In some examples, theocclusion detection mechanism 500 may include sensor configured to monitor motor current. For example, should occlusion occur, a resulting increase in motor torque may be detectable via measuring an increase in motor current. The occlusion detection mechanism 500 may be configured to actuate the occlusion switch 450 based on an increase in motor current above a predetermined motor current threshold.

[0110] The occlusion detection mechanism 500 may be configured to be calibrated. For example, the relevant threshold (for example pressure, flow rate and / or motor current) may be adjustable, for example to enable early detection of occlusion while minimising false alarms. In some examples, the occlusion detection mechanism 500 may employ two or more of the examples described above in combination to improve sensitivity and reduce false alarms.

[0111] The device 10 may further include an air elimination member 350 configured to remove air bubbles from the fluid in the flexible tube 300. The air elimination member 350 may be positioned in line with the flexible tube 300, downstream of the pump head 100 and / or the occlusion detection mechanism 500.

[0112] In use, the flexible tube 300 is assembled into the second module 40, and the fluid delivery device 10 is assembled with the first module 30 connected to the second module 40 to couple the second drive members 220, 230. The first portion 302 of the flexible tube 300 is connected to a fluid source and the second portion 304 of the flexible tube is connection with a desired fluid delivery location. In some examples, the flexible tube may comprise a medical catheter. The second portion 304 of the flexible tube 300 may be connected with an end of the catheter (or connected with another catheter) implanted at a target tissue site for delivery of fluid medicament. A priming step may be performed if required. The device 10 is then activated to cause the motor 210 to provide driving force to the first and second drive members 220, 230, to exert a driving force on the compression elements 120 to move the compression elements 120 within the pump head housing 110, compressing the flexible tube 300, thereby to drive a fluid within the tube 300 in the direction of movement of the compression elements 120 and to deliver fluid to the desired delivery location.

[0113] It will be appreciated by persons skilled in the art that numerous variations and / or modifications may be made to the above-described embodiments, without departing from the broad general scope of the present disclosure. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.

Claims

CLAIMS:

1. A fluid delivery device including at least one peristaltic pump assembly, the peristaltic pump assembly comprising: a pump head comprising: a pump head housing having an arcuate inner surface; and a plurality of compression elements movable within the pump head housing; and a drive mechanism operable to exert a driving force on the compression elements to move the compression elements within the pump head housing, the drive mechanism comprising: a motor; a first drive member configured to be rotatably driven by the motor about a rotational axis, the first drive member comprising a first coupling mechanism; and a second drive member comprising a second coupling mechanism releasably connectable with the first coupling mechanism to rotationally couple the second drive member to the first drive member for conjoined rotation therewith, wherein the second drive member comprises a plurality of radially spaced connectors, wherein each connector is configured for coupling to a respective one of the compression elements, wherein the pump head housing is configured to receive a portion of a flexible tube extending between the arcuate inner surface and the compression elements, such that the driven movement of the compression elements peristaltically compresses the flexible tube against the arcuate inner surface of the pump head housing, thereby to drive a fluid within the tube in the direction of movement of the compression elements.

2. The fluid delivery device of claim 1 wherein the driven movement of the compression elements follows a circular path extending about the rotational axis and concentric with the arcuate inner surface.

3. The fluid delivery device of claim 1 or claim 2, wherein the first and second coupling mechanisms each comprise an array of radially spaced elongate prongs, each prong extending substantially parallel to the rotational axis, wherein the prongs of the first drive member are configured to be received in interdigitating engagement with the prongs of the second drive member.

4. The fluid delivery device of claim 3, wherein, when the first and second coupling mechanisms are engaged, abutting surfaces of adjacent prongs provide drive surfaces for torque transmission between the first and second drive members.

5. The fluid delivery device of claim 3 or claim 4, wherein the prongs have a tapered shape.

6. The fluid delivery device of any one of claims 3 to 5, wherein each prong includes a flank portion extending substantially parallel with the rotational axis.

7. The fluid delivery device of any one of claims 3 to 6, wherein each prong includes an angled tip portion.

8. The fluid delivery device of claim 7, wherein the angled tip portions of the prongs are configured for sliding engagement during assembly of the first and second coupling mechanisms to rotationally align the first and second drive members, facilitating the interdigitating engagement of the prongs.

9. The fluid delivery device of any one of the preceding claims, wherein one of the first drive member and the second drive member comprises a male connection feature configured to be received by a corresponding female connection feature in the other of the first drive member and the second drive member.

10. The fluid delivery device of any one of the preceding claims, wherein the pump head comprises a spindle positioned between and in contact with the compression elements, wherein the compression elements revolve around the spindle.

11. The fluid delivery device according to any one of the preceding claims comprising a first module and a second module connectable to the first module, wherein the first module comprises the motor and the first drive member, and wherein the second module comprises the pump head and the second drive member.

12. The fluid delivery device of claim 11, wherein the second module is configured for sterilisation prior to connection with the first module.

13. The fluid delivery device of claim 11 or claim 12, further comprising a controller configured to control operation of the motor.

14. The fluid delivery device of claim 13, comprising a tamper evident mechanism configured to detect disconnection of the first module from the second module.

15. The fluid delivery device of any one of the preceding claims, further comprising the flexible tube.

16. The fluid delivery device of claim 15 comprising an occlusion detection mechanism for detecting an occlusion of the flexible tube during operation of the fluid delivery device.

17. The fluid delivery device of claim 16, wherein the occlusion detection mechanism comprises a sensor configured to detect expansion of an expandable member in fluid communication with the flexible tube in response to an increase in pressure within the flexible tube.

18. The fluid delivery device of any one of the preceding claims, including first and second peristaltic pump assemblies according to any one of claims 1-10.

19. The fluid delivery device of claim 18, wherein the first and second peristaltic pump assemblies are provided in a symmetrically mirrored arrangement, such that respective compression elements of the first and second peristaltic pump assemblies are driven in rotationally opposite directions.

20. The fluid delivery device of claim 19, wherein respective motors of the first and second peristaltic pump assemblies are encoded to provide identical rotational output.

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