Electrofluidic standard module and custom circuit board assembly

• US 5,640,995 A
• Filed: 03/14/1995
• Issued: 06/24/1997
• Est. Priority Date: 03/14/1995
• Status: Expired due to Term

• Current Assignee: Baxter International Inc., IC Sensors, Inc. (TE Connectivity Ltd. (United Kingdom))
• Original Assignee: Baxter International Inc.
• Inventors: Packard, Warren J., Jerman, John H.
• Primary Examiner(s): Hepperle, Stephen M.
• Application Number:
  US08/404,301
• Time in Patent Office: 833 Days
• Field of Search: 137/884, 137/597, 251/129.01
• US Class Current: 137/597
• CPC Class Codes: A61M 1/14 Dialysis systems; Artificial kidneys; Blood oxygenators semi-permeable membranes characterised by the material, manufacturing processes therefor B01D71/00 ; Reciprocating systems for treatment of body fluids, e.g. single needle systems for hemofiltration or pheresis
• CPC Class Codes: A61M 1/1524 the interface providing means for actuating on functional elements of the cassette, e.g. plungers
• CPC Class Codes: A61M 1/155 with treatment-fluid pumping means or components thereof
• CPC Class Codes: A61M 1/1561 at least one cassette surface or portion thereof being flexible, e.g. the cassette having a rigid base portion with preformed channels and being covered with a foil
• CPC Class Codes: A61M 1/1565 Details of valves
• CPC Class Codes: A61M 2205/12 with interchangeable cassettes forming partially or totally the fluid circuit
• CPC Class Codes: F15C 5/00 Manufacture of fluid circuit elements; Manufacture of assemblages of such elements integrated circuits
• CPC Class Codes: F16K 2099/0074 using photolithography, e.g. etching
• CPC Class Codes: F16K 2099/0084 Chemistry or biology, e.g. "lab-on-a-chip" technology
• CPC Class Codes: F16K 2099/0086 Medical applications
• CPC Class Codes: F16K 2099/009 Fluid power devices
• CPC Class Codes: F16K 99/0001 Microvalves microdevices B81B1/00; manufacture or treatment of devices or systems in or on a substrate B81C1/00; microfluidic structures B01L3/5027; micropumps F04B19/006
• CPC Class Codes: F16K 99/0005 Lift valves
• CPC Class Codes: F16K 99/0034 Operating means specially adapted for microvalves
• CPC Class Codes: F16K 99/0044 using thermo-electric means
• CPC Class Codes: Y10T 137/87249 Multiple inlet with multiple outlet
• CPC Class Codes: Y10T 137/87885 Sectional block structure

Abstract

A miniature electrofluidic module is disclosed, for receiving one or more fluids and for receiving an electrical connection. In accordance with one aspect of the invention, the module includes a substantially flat fluidic manifold layer for fluid distribution, a substantially flat electrical layer including an electrical circuit, and a substantially flat device layer including micromachined devices. The devices may include electrically actuated valves for modulating the flow of fluids. In another aspect of the invention, an electrofluidic module is combined with an electrofluidic circuit board. In a further aspect, an electrofluidic system such as a dialysate handling system is disclosed, including a fluidic fixture and an electrofluidic assembly incorporating electrofluidic devices. In a still further aspect of the invention, a method is disclosed for interfacing micromachined devices to electrical and fluidic interfaces on a fixture, including packaging the devices into a module and providing electrical and fluidic interfaces between the module and the fixture.

Claims

1. A miniature electrofluidic module for receiving a fluid and an electrical connection, said module comprising:

a substantially flat manifold layer having at least one fluidic inlet and an internal fluidic passageway connected to the inlet for receiving fluid;

a substantially flat electrical layer having a plurality of electrical layer fluidic passageways extending therethrough and connected to receive fluid from the internal fluidic passageway, the electrical layer having an electrical circuit comprising a plurality of individual micromachined device circuits thereon; and

a substantially flat device layer having a plurality of micromachined devices thereon, each micromachined device being in electrical communication with one of the individual micromachined device circuits and in fluid communication with the respective electrical layer fluidic passageways to receive fluid therefrom.

4. A module in accordance with claim 1 wherein the electrical layer has an electrical trace thereon to form the electrical circuit;

and connector elements are mounted on the module and are connected to the electrical trace and are adapted to be connected to other connectors leading to an electric controller.

5. A module in accordance with claim 1 wherein mechanical interface means of a predetermined configuration is provided for interfacing with a fixture to which the module is attached to properly position the module on the fixture.

9. A module in accordance with claim 1 wherein the module comprises:

a flat-pack layered body having a flush mountable face on the manifold layer for flush mounting against a mating face of a fixture for aligning fluidically therewith; and

electrical connectors on the flat-pack layered body directed toward the fixture to engage connectors on the fixture when the module is flush mounted against the fixture.

2. A miniature electrofluidic module for receiving a fluid and an electrical connection, said module comprising:

a substantially flat first manifold layer having at least one fluidic inlet and an internal fluidic passageway connected to the inlet for receiving fluid;

a substantially flat electrical layer having an electrical circuit including circuit traces thereon, the electrical layer being positioned between the device layer and the first manifold layer, the electrical layer having fluidic passageways formed therein to allow fluid to flow from the first manifold layer and through the electrical layer;

a substantially flat micromachined device layer having a plurality of micromachined devices thereon in fluid communication with the fluidic passageway in the first manifold layer via the fluidic passageways in the electrical layer and in electrical communication with the electrical circuit on the electrical layer; and

a second flat manifold layer having fluidic inputs and internal fluidic passageways, said second layer being disposed on a side of the micromachined device layer opposite from the side on which is located the first manifold layer for returning fluid flow to the first manifold layer.

3. A module in accordance with claim 2 wherein the first mentioned manifold layer has both fluidic inputs and outputs therein on one face of the module for flush mounting to a face of fixture.

6. A miniature electrofluidic module for receiving a fluid and an electrical connection, said module comprising:

a substantially flat first manifold layer having at least one fluidic inlet and an internal fluidic passageway connected to the inlet for receiving fluid;

a substantially flat electrical layer having an electrical circuit thereon;

a substantially flat device layer having a plurality of micromachined electrofluidic valves thereon in fluid communication with the fluidic passageway in the first manifold layer and in electrical communication with the electrical circuit on the electrical layer, wherein the device layer is a middle layer, the first manifold layer being disposed on a first side of the middle layer; and

a second manifold layer disposed on an opposite side of the middle layer with fluidic passageways for returning fluid flow to the first manifold layer.

7. A miniature electrofluidic module for receiving a fluid and an electrical connection, said module comprising:

a substantially flat manifold layer having at least one fluidic inlet and an internal fluidic passageway connected to the inlet for receiving fluid;

a substantially flat electrical layer having an electrical circuit thereon;

a substantially flat device layer having a plurality of micromachined devices mounted side-by-side in a plane thereon in fluid communication with the fluidic passageway in the manifold layer and in electrical communication with the electrical circuit on the electrical layer, each of the micromachined devices comprising a valve member having an electrothermal member that displaces to modulate fluid flow with a change in electrical current applied thereto.

8. A miniature electrofluidic module for receiving a fluid and an electrical connection, said module comprising:

a substantially flat manifold layer having at least one fluidic inlet and an internal fluidic passageway connected to the inlet for receiving fluid, wherein the manifold layer comprises a first substrate having standard fluidic passageways arranged in a standard pattern, and a second substrate having fluidic passageways for further fluid distribution and in fluid communication with the standard fluidic passageways in the first substrate;

a substantially flat electrical layer having an electrical circuit thereon; and

a substantially flat device layer having a plurality of micromachined devices thereon in fluid communication with the fluidic passageways in the manifold layer and in electrical communication with the electrical circuit on the electrical layer.

10. A miniature electrofluidic module having a fluidic inlet and an electrical connection, comprising:

a flat-pack, modular, layered body having a face;

an inlet/outlet manifold layer on the face having at least one inlet for inlet fluid flow in one direction and at least one outlet for return fluid flow in a return direction;

a plurality of micromachined devices in a middle layer of the body having fluidic passageways therein to modulate fluid flow;

an electrical layer in the body adjacent the micromachined devices having electrical circuits for operating the micromachined devices; and

a return manifold on the modular body on the other side of the device layer to receive fluid flow from one part of the inlet/outlet manifold layer and to redirect the fluid flow to another part of the inlet/outlet manifold layer.

11. An electrofluidic module in accordance with claim 10 wherein a pair of electrical connectors are mounted on the modular body and are electrically connected to the electrical circuits for selective operation of the micromachined devices.

12. An electrofluidic module in accordance with claim 11 wherein the inlets and outlets are arranged in standard, predetermined positions for cooperation with a standard pattern of fluidic passageways in a fixture;

and

the electrical connectors being positioned in standard positions for mating with connectors on the fixture so that the module may be readily connected and disconnected with respect to the fixture.

13. A modular electrofluidic multiplexer for control of a fluid in response to electrical signals, comprising:

a substantially flat manifold layer having at least one fluidic inlet, an internal fluidic passageway connected to the inlet for receiving fluid flow therethrough;

a substantially flat electrical layer having a plurality of electrical layer fluidic passageways extending therethrough and connected to receive fluid from the internal fluidic passageway, the electrical layer having a plurality of individual micromachined actuator electrical circuit paths formed thereon for communication with a source of electrical signals;

a substantially flat, micromachined device layer having a plurality of micromachined actuators positioned thereon each micromachined actuator being in electrical communication with one of the individual micromachined actuator electrical circuit paths and in fluid communication with the respective electrical layer fluidic passageways to receive fluid therefrom; and

a plurality of fluidic outlets coupled via fluidic outlet passages in fluid communication to the micromachined actuators so that in response to the electrical signals the micromachined actuators can selectively connect and disconnect the inlet from fluid communication with one or more of the outlet fluid paths.

14. An electrofluidic multiplexer in accordance with claim 13, wherein at least two of the micromachined actuators comprise micromachined valves.

15. An electrofluidic multiplexer in accordance with claim 14, wherein the micromachined valves each comprise a silicon micromachined valve.

16. An electrofluidic assembly having separable electrical and fluidic connections, said assembly comprising:

at least one electrofluidic module having a substantially flat manifold layer having at least one fluidic inlet and an internal fluidic passageway connected to the fluidic inlet for receiving fluid, a substantially flat electrical layer having a plurality of individual micromachined device electrical circuits and a plurality of electrical layer fluidic passageways in communication with the internal fluidic passageway, a substantially flat device layer having a plurality of micromachined devices thereon in fluid communication with the respective of the electrical layer fluidic passageways and in electrical communication with respective ones of the individual micromachined device electrical circuits;

the substantially flat manifold layer on the electrofluidic module having a fluidic interface located at a predetermined, standard position on one side of the module and having a fluidic passageway in fluid communication with the passageway in the electrofluidic device;

a first electrical connector on the module connected to the electrical circuit;

an electrofluidic circuit board having a standard, fluidic interface with a releasable mating connection with the standard fluidic interface of said module; and

a second electrical connector on the electrofluidic circuit board for a releasable connection to the first electrical connector so that the electrofluidic module can be detachably connected to the electrofluidic circuit board.

17. An assembly in accordance with claim 16 wherein the fluidic interface on the fluidic manifold of each electrofluidic module has both fluidic inlets and outlets on a face of the module which is flush mounted against an opposing face of the electrofluidic circuit board.

18. An assembly in accordance with claim 16 wherein a plurality of electrofluidic devices are mounted in the electrofluidic module and separate electrical circuits are provided in the module for each of the electrofluidic devices, the first and second electrical connectors providing individual circuit connections for each of the electrofluidic devices.

19. A modular assembly in accordance with claim 16 wherein the electrofluidic device comprises a miniature, solenoid valve having fluid flow therethrough.

20. An assembly in accordance with claim 16 wherein the electrofluidic circuit board has electrical traces thereon, and a third electrical connector is connected to the traces to provide an electrical flow path to the connected first and second connectors.

21. An assembly in accordance with claim 16 further comprising releasable fastener means for detachably connecting the electrofluidic module to the electrofluidic circuit board.

22. An assembly in accordance with claim 20 wherein the releasable fastener means comprises at least one threaded bolt and one mating threaded groove.

23. An assembly in accordance with claim 16 wherein the electrofluidic module has a pop-in and pop-out connection with the electrofluidic circuit board to allow easy detachable mounting of the electrofluidic module.

24. In an electrofluidic system, the combination comprising:

a fixture having fluidic passageways therein for the flow of a fluid;

an electrofluidic member mounted on the fixture over the fixture passageways and having member passageways in fluid communication with the fixture passageways;

a plurality of micromachined devices mounted on the electrofluidic member and having fluidic passageways connected to the inlets and outlets of the electrofluidic member;

individual micromachined device electrical circuits on the electrofluidic member ones of which are respectively connected to the individual micromachined devices to operate the same to modulate fluid flow through the member passageways within the electrofluidic member; and

return fluid flow directing means associated with the micromachined devices for directing fluid to return to the electrofluidic member.

25. An electrofluidic system in accordance with claim 24 wherein the return fluid flow directing means comprises a manifold member common to a plurality of micromachined devices.

26. An electrofluidic system in accordance with claim 24 wherein means permanently secures the micromachined devices to the electrofluidic member.

27. An electrofluidic system in accordance with claim 24 wherein an electrofluidic module contains a plurality of micromachined devices and the electrofluidic module is detachably connected electrically and fluidically to the electrofluidic member.

28. An electrofluidic system in accordance with claim 27 wherein the electrofluidic member comprises a printed circuit board having an electrical connector thereon for detachable connection to an electrical connector on the electrofluidic module.

29. In an electrofluidic system, the combination comprising:

a fixture having fluidic passageways therein for fluid communication with other devices;

an electrofluidic member mounted on the fixture and having member passageways mounted over the fixture passageways to communicate fluid flow with the other devices;

an electrofluidic module on the electrofluidic member having a plurality of micromachined valves for modulating fluid flow between the module and the member;

an electrical layer on the electrofluidic member having individual circuit paths for controlling the respective ones of the micromachined valves to modulate the fluid flow through the electrical layer; and

an electrical connector on the electrofluidic module for connection to an electrical controller for operating the electrofluidic devices.

30. A system in accordance with claim 29 wherein the electrofluidic module has fluidic inlets and fluidic outlets in one face thereof flush mounted against the electrofluidic member;

and the member and electrofluidic module have separable, interconnected electrical connectors.

31. A system in accordance with claim 29 wherein the electrofluidic devices comprise micromachined valves and wherein the module is provided with predetermined, standard fluidic inlets and outlets for matching with the member passageways.

32. In an electrofluidic system, the combination comprising:

a fixture having fluidic passageways therein for fluid communication with other devices;

a flat layer with fluidic inlets and outlets mounted over the passageways to communicate fluid flow to and from the other devices, the flat layer having circuit paths for controlling the electrofluidic micromachined valves to modulate the fluid flow;

a plurality of electrofluidic micromachined valves thereon for modulating fluid flow among the inlets and outlets; and

an electrical connector on the flat layer for electrical connection via a plurality of respective individual electrofluidic micromachined valve electrical circuits to the electrofluidic micromachined valves and to an electrical controller for operating the electrofluidic micromachined valves.

33. In an electrofluidic dialysate handling system, the combination comprising:

a piston body having a plurality of valve actuators thereon and fluidic passageways in the piston body for fluid communication with the valve actuators;

an electrofluidic member mounted on the piston body and having member passageways mounted over the body passageways to communicate fluid flow to the valve actuators;

the electrofluidic member having a plurality of electrofluidic modules thereon for modulating fluid flow between the electrofluidic member and the modules;

an electrical layer on the electrofluidic member having circuit paths for controlling the respective electrofluidic modules to modulate the fluid flow; and

an electrical connector on each of the electrofluidic modules for connection to an electrical controller for operating the electrofluidic devices.

34. A system in accordance with claim 33 wherein the electrofluidic modules each have fluidic inlets and fluidic outlets in one face thereof flush mounted against the electrofluidic member;

and the electrofluidic member and electrofluidic modules have separable, interconnected electrical connectors.

35. A system in accordance with claim 33 wherein the modules each have at least one micromachined valve therein and the modules each have predetermined, standard fluidic inlets and outlets for matching with the member passageways.

36. In an electrofluidic dialysate handling system, the combination comprising:

a pneumatic cassette interface for supplying selected pneumatic control signals to a disposable cassette of a disposable dialysate delivery set to enable the disposable to deliver dialysate to a patient, the cassette interface having fluidic passageways therein for the flow of air;

an electrofluidic member mounted on the pneumatic cassette interface over the pneumatic cassette interface passageways and having member passageways in fluid communication with the pneumatic cassette interface passageways;

a plurality of micromachined valves mounted on the electrofluidic member and having fluidic passageways connected to the member passageways;

individual electrical circuits on the electrofluidic member connected to respective ones of the micromachined valves to operate the same to modulate air flow through the member passageways; and

return fluid flow directing means associated with the micromachined devices for directing air to return to the electrofluidic member.

37. A system in accordance with claim 36 wherein the micromachined devices are mounted permanently on the electrofluidic member and the electrofluidic member is mounted permanently on the fixture.