CA-3095364-C - LIQUID PUMPING CASSETTES, PRESSURE DISTRIBUTION MANIFOLD, AND RELATED METHODS

CA3095364CCA 3095364 CCA3095364 CCA 3095364CCA-3095364-C

Abstract

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

Inventors

Kevin L. Grant
Benjamin E. Colburn
Joseph M. Rauseo
Benjamin J. Doucette
Marc J. Gorayeb

Assignees

DEKA PRODUCTS LIMITED PARTNERSHIP

Dates

Publication Date: 20260505
Application Date: 20190329
Priority Date: 20180330

Claims (13)

What is claimed is: 1. A fluid-handling cassette assembly comprising: a middle cassette interposed between a first outer cassette and a second outer cassette; each said cassette comprising: a mid-plate positioned between a first plate and a second plate, said plates having a length, a width and a plate thickness, a first side of the mid-plate opposing the first plate and a second side of the mid-pate opposing the second plate; the first plate spaced apart from the mid-plate defining a width of a first interplate space, and the second plate spaced apart from the mid-plate defining a width of a second inter-plate space; an edge of each said cassette having a cassette thickness defined by the thickness of each plate plus the width of the first and second inter-plate spaces, and a face of each said cassette being defined by the length and width of the first or second plate; a plurality of diaphragm valves or pumps comprising valve or pump actuation chambers connected to actuation channels running parallel to the face of each said cassette within the first or second inter-plate space, and terminating in corresponding cassette valve or pump actuation ports at a first edge of each said cassette between the first or second inter-plate space; and a fluid-handling pod positioned in an inter-cassette space between the middle cassette and the first or second cassette; said pod having a fluid connection to fluid channels in the middle, first or second cassette via a fluid conduit penetrating the face of the middle, first or second cassette; wherein the first edge of the middle, first and second cassettes are located on a first side of the cassette assembly, so that the cassette valve or pump actuation ports are configured to plug into or unplug from an actuation port receptacle assembly opposite the first side of the cassette assembly.
2. The cassette assembly of claim 1, wherein the fluid-handling pod comprises a diaphragm pump pod having an actuation and a fluid connection to the actuation channels and the fluid channels in the middle, first or second cassette via an actuation 80 Date Re9ue/Date Recieved 2024-06-05 conduit and the fluid conduit, each conduit penetrating the face of the middle, first or second cassette.
3. The cassette assembly of claim 2, wherein the actuation conduit of the diaphragm pump pod connects to one of the actuation channels in the first or second inter-plate space of said middle, first or second cassette, and has an uninterrupted connection to a cassette actuation port for the diaphragm pump pod on the first edge of said middle, first or second cassette.
4. The cassette assembly of claim 2, wherein the fluid conduit of the diaphragm pump pod connects to one of the fluid channels in the first or second inter-plate space of said middle, first or second cassette, and connects with one of the plurality of diaphragm valves in said cassette, and wherein one of the actuation channels of said diaphragm valve connects to a cassette actuation port for said diaphragm valve in the first edge of said middle, first or second cassette.
5. The cassette assembly of claim 1, wherein the fluid conduit is rigid.
6. The cassette assembly of claim 5, comprising a plurality of fluid-handling pods between the middle cassette and the first cassette, and between the middle cassette and the second cassette, and wherein associated fluid conduits of this plurality of fluidhandling pods are rigid and provide strnctural support for the cassette assembly.
7. The cassette assembly of claim 1, comprising a cassette assembly frame configured to enhance structural stiffness of the cassette assembly, the cassette assembly frame comprising a rigid support plate on a second side of the cassette assembly opposite the first side of the cassette assembly, said support plate configured to engage a cassette loading apparatus opposite the actuation port receptacle assembly.
8. A fluid-handling cassette assembly comprising: a middle cassette interposed between a first outer cassette and a second outer cassette; each said cassette comprising: 81 Date Re9ue/Date Recieved 2024-06-05 a mid-plate positioned between a first plate and a second plate, said plates having a length, a width and a plate thickness, a first side of the mid-plate opposing the first plate and a second side of the mid-pate opposing the second plate; the first plate spaced apart from the mid-plate defining a width of a first interplate space, and the second plate spaced apart from the mid-plate defining a width of a second inter-plate space; an edge of each said cassette having a cassette thickness defined by the thickness of each plate plus the width of the first and second inter-plate spaces, and a face of each said cassette being defined by the length and width of the first or second plate; a plurality of diaphragm valves or pumps comprising valve or pump actuation chambers connected to actuation channels running parallel to the face of each said cassette within the first or second inter-plate space, and terminating in corresponding cassette valve or pump actuation ports at a first edge of each said cassette between the first or second inter-plate space; a first fluid-handling pod positioned in an inter-cassette space between the middle cassette and the first or second cassette; said pod having a fluid connection to fluid channels in the middle, first or second cassette via a fluid conduit penetrating the face of the middle, first or second cassette; and a second fluid-handling pod comprising a diaphragm pump pod having an actuation and a fluid connection to the actuation and fluid channels in the middle, first or second cassette via an actuation conduit and a fluid conduit, each conduit penetrating the face of the middle, first or second cassette; wherein the first edge of the middle, first and second cassettes are located on a first side of the cassette assembly, so that the cassette valve or pump actuation ports are configured to plug into or unplug from an actuation port receptacle assembly opposite the first side of the cassette assembly.
9. The cassette assembly of claim 8, wherein the actuation conduit of the diaphragm pump pod connects to one of the actuation channels in the first or second inter-plate space of said middle, first or second cassette, and has an uninterrupted connection to a cassette actuation port for the diaphragm pump pod on the first edge of said middle, first or second cassette. 82 Date Re9ue/Date Recieved 2024-06-05
10. The cassette assembly of claim 8, wherein the fluid conduit of the diaphragm pump pod connects to one of the fluid channels in the first or second inter-plate space of said middle, first or second cassette, and connects with one of the plurality of diaphragm valves in said cassette, and wherein one of the actuation channels of said diaphragm valve connects to a cassette actuation port for said diaphragm valve in the first edge of said middle, first or second cassette.
11. The cassette assembly of claim 8, wherein the fluid conduit is rigid.
12. The cassette assembly of claim 11, comprising a plurality of fluid-handling pods between the middle cassette and the first cassette, and between the middle cassette and the second cassette, and wherein associated fluid conduits of this plurality of fluidhandling pods are rigid, providing structural support for the cassette assembly.
13. The cassette assembly of claim 8, comprising a cassette assembly frame configured to enhance structural stiffness of the cassette assembly, the cassette assembly frame comprising a rigid support plate on a second side of the cassette assembly opposite the first side of the cassette assembly, said support plate configured to engage a cassette loading apparatus opposite the actuation port receptacle assembly. 83 Date Re9ue/Date Recieved 2024-06-05

Description

LIQUID PUMPING CASSETTES, PRESSURE DISTRIBUTION MANIFOLD, AND RELATED METHODS FIELD OF THE INVENTION This disclosure generally relates to improvements in the design and construction of fluid pumping or mixing cassettes, cassette assemblies, their constituent parts, and associated devices. BACKGROUND 10 Liquid-handling cassettes comprising diaphragm pumps and/or valves can be actuated fluidically (either hydraulically or pneumatically). In some examples, a cassette is designed to be fluidically connected to a pneumatic actuation manifold having electromechanical valves that selectively distribute positively or negatively pressurized gas or air to the cassette. A programmable electronic controller can be used to control the 15 electromechanical valves to selectively deliver positive or negative pneumatic pressure to various pumps or valves of the cassette in a pre-detennined manner. Some fluid-handling cassettes can be substantially planar in shape, having a broad side flanked by a thin or narrow side having a relatively smaller thickness that the overall broad side dimensions of the cassettes. Liquid inlet and outlet ports can be incorporated 20 into the edge or thin side of the cassette. But in many of these devices, actuation ports for the cassette have been located on the face or broad side of the cassette directly over the actuation chambers of the pumps or valves being controlled. This generally provides the shortest route for an actuation channel in the cassette from an external cassette actuation port to the actuation chamber and diaphragm of a pump or valve in the cassette. 25 Furthermore, in many cases the pumping or valve stations or regions of the cassette - comprising either the actuation chamber on one side or the liquid carrying chamber on the opposing side - may be defined by spheroid or hemi-spheroid chamber walls that extend above the plane of the cassette face, which makes the overall cassette thicker than desirable in some applications. Tn other cases, a pump module may comprise a set of blocks 30 sandwiched or laminated together, with the pneumatic actuation channels or fluid channels embedded within one or more of the blocks. This arrangement may also result in an overall device thickness greater than desirable for certain applications. Some applications may 1 Date Re9ue/Date Recieved 2024-06-05 require a plurality of fluid handling cassettes to be mounted next to each other in tight spaces. In these cases, it may be desirable to position a number of cassettes adjacent to one another, to stack them against each other, or at least to place their broad sides face-toface in close proximity. Reducing or minimizing the thickness of the individual cassettes 5 constituting these assemblies may be particularly desirable. It may be advantageous to arrange for a pump cassette to plug directly into its associated pressure distribution manifold (for example, a manifold that selectively delivers pneumatic pressure to the pump cassette under control of an electronic controller). In previously disclosed embodiments of a hemodialysis system using pneumatically actuated 10 self-contained pump cassettes, the pump cassettes were connected to a corresponding pneumatic manifold via flexible tubes, which has led to significant challenges during assembly and in their operation. If a pump cassette can be located close to its associated manifold, a direct plug-in connection between the two would have substantial advantages. Under these circumstances, it would be particularly advantageous to have a compact 15 manifold that allows for a direct interface to a pump cassette, arranged in such a manner as to allow the cassette or cassette assembly to be plugged into and unplugged from the actuation ports of the manifold with minimal effort. In the design and operation of a pneumatic distribution manifold, the ability to use binary pressure control valves rather than continuously variable orifice valves would also 20 provide significant advantages in both cost and reliability. But in this case, the control of pressure delivery to individual cassette pumps or valves by binary pressure control valves poses additional challenges that must be overcome. A sufficiently robust electronic controller can be programmed to use control algorithms to control the frequency and duration of binary valve actuation to achieve precise control of associated pneumatically 25 actuated pumps or valves. SUMMARY In an embodiment, a pump and/or valve cassette has a relatively planar shape, with 30 a broad side flanked by a thinner narrow side or edge. It comprises a midplate positioned between two outer plates: a first outer plate facing a first side of the midplate, and a second outer plate facing an opposing second side of the midplate. The first outer plate is spaced apart from the midplate to form a first inter-plate space. The second outer plate is spaced apart from the midplate to form a second inter-plate space. The thickness of the firs