Diaphragm type blood pump for medical use

• US 4,411,603 A
• Filed: 06/24/1981
• Issued: 10/25/1983
• Est. Priority Date: 06/24/1981
• Status: Expired due to Term

• Current Assignee: Baxter International Inc.
• Original Assignee: Cordis Dow Corp.
• Inventors: Kell, Michael J.
• Primary Examiner(s): Gluck, Richard E.
• Application Number:
  US06/276,752
• Time in Patent Office: 853 Days
• Field of Search: 417/479, 417/560, 128/214 F, 128/214 G, 128/DIG. 12, 137/855, 137/856, 604/153, 604/247
• US Class Current: 417/479
• CPC Class Codes: A61M 60/113 in other functional devices, e.g. dialysers or heart-lung machines
• CPC Class Codes: A61M 60/37 Haemodialysis, haemofiltration or diafiltration
• CPC Class Codes: A61M 60/438 the force acting on the blood contacting member being mechanical
• CPC Class Codes: A61M 60/837 Aspects of flexible displacement members, e.g. shapes or materials
• CPC Class Codes: A61M 60/851 Valves
• CPC Class Codes: A61M 60/892 Active valves, i.e. actuated by an external force
• CPC Class Codes: A61M 60/894 Passive valves, i.e. valves actuated by the blood
• CPC Class Codes: A61M 60/896 having flexible or resilient parts, e.g. flap valves
• CPC Class Codes: F04B 43/02 having plate-like flexible members, e.g. diaphragms F04B43/14 takes precedence
• CPC Class Codes: Y10S 128/12 Pressure infusion
• CPC Class Codes: Y10T 137/7891 Flap or reed

Abstract

A positive displacement pump for delivery of blood, or the like, from patients to an extracorporeal circuit, for purification, as in hemodialysis treatments. The pump is small, and sufficiently inexpensive to be discarded after one use. The pump comprises a single blood chamber attached to inlet and outlet conduits separated from the chamber and each other by low resistance flapper valves. The flapper valves are integral with a flexible diaphragm which forms one side of the blood chamber and are operative to close the outlet valve and to open the inlet valve to fill the blood cavity responsive to withdrawal of the diaphragm from the blood chamber cavity and to reverse each valve upon penetration of the diaphragm into the blood chamber to deliver uniformly small increments of blood to an artificial kidney or other blood treatment device.

Claims

1. A blood pump for medical use comprising body means defining a blood chamber portion, a plunger receiving opening, and inlet and outlet conditions;

a diaphragm of resiliently flexible material extending across and sealing said opening from said chamber portion and cooperating with said chamber portion to define a blood chamber, said diaphragm being movable in a pumping action for alternately reducing and increasing the volume of said blood chamber;

said inlet and outlet conduits communicating with said blood chamber;

inlet and outlet flapper valves or resiliently yieldable flexible material associated with said inlet and outlet conduits respectively for alternately closing and opening the communication between said inlet conduit and chamber and simultaneously opening and closing the communication between said outlet conduit and chamber upon said pumping action of said diaphragm reducing and increasing said volume respectively;

each flapper valve comprising a single element of resiliently yieldable flexible material having a disc portion, a fixed portion, and a web portion connecting said disc and fixed portions;

the disc portion of each flapper valve overlying the opening of its associated conduit into said blood chamber and being sufficiently thick to resist collapsing into the latter opening in response to fluid pressure changes in said blood chamber during said pumping action, the fixed portion of each flapper valve having a thickness substantially equal to the thickness of the disc portion and being secured to said body means, and the web portion of each flapper valve being reduced in both width and thickness with respect to the disc portion to effect a highly flexible hinge facilitating alternate opening and closing hinge movement of the connected disc portion; and

means for limiting opening hinge movement of each disc portion to a predetermined small angle comprising a separate ramp portion of said body means extending at said angle from adjacent to each web portion and in the downstream direction of fluid flow.

2. The combination according to claim 1, said diaphragm and inlet and outlet flapper valves comprising a single diaphragm member of said resiliently yieldable flexible material, said diaphragm having a thickness greater than the thickness of said flapper valves and having additionally thickened portions extending into said plunger receiving opening exteriorly of said blood chamber for connection with a reciprocal plunger.

3. The combination according to claim 2, said diaphragm member having an annular thickening around said plunger receiving opening and having separate annular thickenings around the openings of said inlet and outlet conduits into said blood chamber, and said body means having annular recesses mating with and receiving said annular thickenings respectively at interference fits and in sealing relationship for securing said thickenings in fixed positions with respect to said body means and for effecting fluid seals between said diaphragm member and body means around each of said openings.

4. The combination according to claim 3, said body means comprising a first body member defining said chamber portion, a second body member having said plunger receiving opening and said inlet and outlet conduits, and a diaphragm support, said diaphragm support and second body member having said annular recesses therein and clamping said diaphragm member therebetween, and said first body member clamping said diaphragm support toward said diaphragm member and second body member.

9. The combination according to claim 1, said body means comprising a first body member defining said chamber portion, a second body member having said plunger receiving opening and said inlet and outlet conduits, and a diaphragm support, said diaphragm support and second body member having said annular recesses therein and clamping said diaphragm member therebetween, and said first body member clamping said diaphragm support toward said diaphragm member and second body member.

5. A blood pump for medical use comprising body means defining a blood chamber portion, a plunger receiving opening, and inlet and outlet conduits;

a diaphragm of resiliently flexible material extending across and sealing said opening from said chamber portion and cooperating with said chamber portion to define a blood chamber, said diaphragm being movable in a pumping action for alternately reducing and increasing the volume of said blood chamber;

said inlet and outlet conduits communicating with said blood chamber;

inlet and outlet flapper valves of resiliently yieldable flexible material associated with said inlet and outlet conduits respectively for alternately closing and opening the communication between said inlet conduit and chamber and simultaneously opening and closing the communication between said outlet conduit and chamber upon said pumping action of said diaphragm reducing and increasing said volume respectively;

each flapper valve comprising a single element of resiliently yieldable flexible material having a disc portion, a fixed portion, and a web portion connecting said disc and fixed portions, the disc portion of each flapper valve overlying the opening of its associated conduit into said blood chamber and being sufficiently thick to resist collapsing into the latter opening in response to fluid pressure changes in said blood chamber during said pumping action, the fixed portion of each flapper valve having a thickness substantially equal to the thickness of the disc portion and being secured to said body means, and the web portion of each flapper valve being reduced in both width and thickness with respect to the disc portion to effect a highly flexible hinge facilitating alternate opening and closing hinge movement of the connected disc portion;

said diaphragm and inlet and outlet flapper valves comprising a single flexible diaphragm member of said resiliently yieldable flexible material, said diaphragm having a thickness greater than the thickness of said flapper valves and having additionally thickened portions extending into said plunger receiving opening exteriorly of said blood chamber for connection with a reciprocal plunger.

6. The combination according to claim 5, said diaphragm member having an annular thickening around said plunger receiving opening and having separate annular thickenings around the openings of said inlet and outlet conduits into said blood chamber, and said body means having annular recesses mating with and receiving said annular thickenings respectively at interference fits and in sealing relationship for securing said thickenings in fixed positions with respect to said body means and for effecting seals between said diaphragm member and body means around each of said openings.

7. The combination according to claim 6, said body means comprising a first body member defining said chamber portion, a second body member having said plunger receiving opening and said inlet and outlet conduits, and a diaphragm support, said diaphragm support and second body member having said annular recesses therein and clamping said diaphragm member therebetween, and said first body member clamping said diaphragm support toward said diaphragm member and second body member.

8. A blood pump for medical use comprising body means defining a blood chamber portion, a plunger receiving opening, and inlet and outlet conduits;

a diaphragm of resiliently flexible material extending across and sealing said opening from said chamber portion and cooperating with said chamber portion to define a blood chamber, said diaphragm being movable in a pumping action for alternately reducing and increasing the volume of said blood chamber;

said inlet and outlet conduits communicating with said blood chamber;

inlet and outlet flapper valves of resiliently yieldable flexible material associated with said inlet and outlet conduits respectively for alternately closing and opening the communication between said inlet conduit and chamber and simultaneously opening and closing the communication between said outlet conduit and chamber upon said pumping action of said diaphragm reducing and increasing said volume respectively;

each flapper valve comprising a single element of resiliently yieldable flexible material having a disc portion, a fixed portion, and a web portion connecting said disc and fixed portions;

the disc portion of each flapper valve overlying the opening of its associated conduit into said blood chamber and being sufficiently thick to resist collapsing into the latter opening in response to fluid pressure changes in said blood chamber during said pumping action, the fixed portion of each flapper valve having a thickness substantially equal to the thickness of the disc portion and being secured to said body means, and the web portion of each flapper valve having a reduced cross sectional area with respect to the disc portion to effect a highly flexible hinge facilitating alternate opening and closing hinge movement of the connected disc portion;

said diaphragm and inlet and outlet flapper valves comprising a single diaphragm member of said resiliently yieldable flexible material, said diaphragm having a thickness greater than the thickness of said flapper valves and having additionally thickened portions extending into said plunger receiving opening exteriorly of said blood chamber for connection with a reciprocal plunger;

said diaphragm member having an annular thickening around said plunger receiving opening and having separate annular thickenings around the openings of said inlet and outlet conduits into said blood chamber, and said body means having annular recesses mating with and receiving said annular thickenings respectively at interference fits and in sealing relationship for securing said thickenings in fixed positions with respect to said body means and for effecting fluid seals between said diaphragm member and body means around each of said openings.