Linear pump and method

• US 6,607,368 B1
• Filed: 11/03/2001
• Issued: 08/19/2003
• Est. Priority Date: 11/03/2001
• Status: Expired due to Fees

• Current Assignee: Anthony Ross, Peter A. Guagliano
• Original Assignee: Anthony Ross, Peter A. Guagliano
• Inventors: Ross, Anthony, Guagliano, Peter A.
• Primary Examiner(s): Freay, Charles G.
• Assistant Examiner(s): GRAY, MICHAEL KUHN
• Application Number:
  US10/008,314
• Time in Patent Office: 654 Days
• Field of Search: 417/412, 417/478, 417/392, 417/394, 604/153, 210/321.78, 210/323.2
• US Class Current: 417/412
• CPC Class Codes: A61M 60/126 implantable via, into, inside, in line, branching on, or around a blood vessel
• CPC Class Codes: A61M 60/148 in line with a blood vessel using resection or like techniques, e.g. permanent endovascular heart assist devices
• CPC Class Codes: A61M 60/284 Linear peristaltic pumps
• CPC Class Codes: A61M 60/427 the force acting on the blood contacting member being hydraulic or pneumatic
• CPC Class Codes: A61M 60/508 Electronic control means, e.g. for feedback regulation
• 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 43/084 the tubular member being deformed by stretching or distortion
• CPC Class Codes: F04B 43/09 Pumps having electric drive

Abstract

A linear pump for pumping a fluid includes a generally tubular shaped bladder 50 sealingly engaged on each end to an end cap 20, 25, forming an inner chamber 14, and including each of an inlet 70 and an outlet 75 inner chamber check valve to fluidly interconnect the inner chamber with the fluid. Each of a plurality of linear motors 40 each may be connected on one end to a respective support rib 30 and on an opposing end pivotally connected to one of the end caps. The support ribs are flexible and have a central portion of the rib engaged with a central portion of the bladder. The plurality of linear motors may be selectively actuated to cause the plurality of support ribs to alternately flex and/or straighten out such that the bladder is condensed or expanded respectively to effect a change in volume of the inner chamber, thereby drawing in or displacing fluid. Bladder extensions 160 may be used to slidably connect the bladder to a respective rib.

Claims

1. A fluid pump for pumping a fluid, comprising:

a pump frame having a central axis extending axially between an inlet end and an outlet end;

an inlet end cap and an outlet end cap each secured to the pump frame and spaced axially from each other;

a plurality of circumferentially spaced support ribs each extending between the inlet end cap and the outlet end cap, each support rib having a central portion between the end caps radially moveable with respect to the central axis;

a plurality of linear motors each connected to a respective support rib, each linear motor including a stator and a shaft linearly moveable relative to the stator to cyclically increase and decrease an effective length of the rib to radially move the central portion of the rib;

a conforming generally tubular bladder radially positioned by the plurality of support ribs and interconnected at one end to said inlet end cap and at an opposite end to said outlet end cap, the bladder defining an inner chamber therein and between the end caps, the inner chamber having a volume;

an inner chamber inlet check valve fluidly interconnecting the fluid with the inner chamber;

an inner chamber outlet check valve fluidly interconnecting the inner chamber with the fluid; and

a power supply for powering each of the plurality of linear motors to cyclically move the plurality of support ribs and thereby vary the volume of the inner chamber to pump fluid.

2. A fluid pump as defined in claim 1, further comprising:

the frame including a housing having a throughbore and a housing axis along the central axis;

an outer chamber between the bladder, the housing, and the end caps;

at least one outer chamber inlet check valve fluidly interconnecting the fluid with the outer chamber; and

at least one outer chamber outlet check valve fluidly interconnecting the outer chamber with the fluid.

3. A fluid pump as defined in claim 1, wherein the linear motor associated with each rib further comprises:

an inlet stator pivotally attached to the inlet end cap;

an outlet stator pivotally attached to the outlet end cap; and

the support rib extending between the inlet stator and the outlet stator; and

the power supply simultaneously extends and retracts the support rib relative to both the inlet stator and the outlet stator.

4. The fluid pump as defined in claim 1, wherein the linear motor associated with each rib further comprises:

the stator pivotally attached to one of the inlet end cap and the outlet end cap; and

the support rib secured at one end to the other of the inlet end cap and the outlet end cap, and an opposing end of the rib moveably engaged with the respective stator.

5. The fluid pump as defined in claim 1, wherein the linear motor associated with each rib further comprises:

the stator secured to an end of the a respective support rib and the shaft pivotally attached to one of the inlet end cap and the outlet end cap.

6. The fluid pump as defined in claim 1, wherein a circumferential width of each support rib is significantly greater than a radial thickness of the support rib, such that circumferential deflection is minimized during radial movement of the rib.

7. The fluid pump as defined in claim 1, wherein the linear motor is electrically powered by the power supply.

8. The fluid pump as defined in claim 1, wherein the linear motor is hydraulically powered by the power supply, such that the stator is a hydraulic cylinder and the shaft is a rod axially moveable relative to the hydraulic cylinder.

9. The fluid pump as defined in claim 1, wherein the flexible generally tubular bladder is formed with a generally hour-glass shape when in a resting position, such that the bladder exerts a radially inward bias when an axially central portion is expanded radially outward, and each of the plurality of support ribs is formed as a relatively axially straight member when in a resting position, such that each of the plurality of support ribs exerts a radially outward bias that opposes the radially inward bias of the bladder when the respective support rib is moved radially inward.

10. The fluid pump as defined in claim 1, wherein each of the plurality of linear motors is positioned external of the bladder.

11. The fluid pump as defined in claim 1, wherein the flexible generally tubular bladder is secured to each rib along at least 20 percent of the axial effective length of the rib between the end plates.

12. The fluid pump as defined in claim 1, further comprising:

a plurality of connectors each extending radially from one of the bladder and a support rib and having an enlarged end; and

the other of the bladder and the support rib including an elongated slot for receiving the enlarged end of each of the plurality of connectors, such that the connectors may move along the elongated slot.

13. A method of pumping a fluid using a fluid pump, the method comprising:

providing a pump frame having a central axis extending axially between an inlet end and an outlet end;

securing each of an inlet end cap and an outlet end cap to the pump frame and spaced axially from each other;

extending each of a plurality of circumferentially spaced support ribs between the inlet end cap and the outlet end cap, each support rib having a central portion between the end caps radially moveable with respect to the central axis;

connecting each of a plurality of linear motors with a respective support rib, each linear motor including a stator and a shaft linearly moveable relative to the stator;

interconnecting a flexible generally tubular bladder to said inlet end cap and interconnecting an opposite end of the bladder to said outlet end cap, the bladder defining an inner chamber therein and between the end caps, the inner chamber having a volume;

interconnecting a central portion of the bladder between the end caps with the central portion of each of the plurality of support ribs;

fluidly interconnecting the fluid with the inner chamber using an inner chamber inlet check valve;

fluidly interconnecting the inner chamber with the fluid using an inner chamber outlet check valve; and

powering each of the plurality of linear motors with a power supply to cyclically increase and decrease an effective length of each of the plurality of support ribs to radially move the central portion of the ribs and thereby vary a volume of the inner chamber.

14. The method of pumping fluid as defined in claim 13, further comprising:

providing the frame with a housing having a throughbore and a housing axis along the central axis;

engaging the housing with each of the inlet end cap outlet end cap to define an outer chamber between the bladder, the housing, and the end caps;

fluidly interconnecting the fluid with the outer chamber using at least one outer chamber inlet check valve;

fluidly interconnecting the outer chamber with the fluid using at least one outer chamber outlet check valve; and

powering each of the plurality of linear motors includes varying a volume of the outer chamber to pump fluid through the outer chamber.

15. The method of pumping fluid as defined in claim 13, wherein engaging each of a plurality of linear motors with a respective rib further comprises:

pivotally attaching an inlet stator to the inlet end cap;

pivotally attaching an outlet stator to the outlet end cap; and

extending the support rib between the inlet stator and the outlet stator; and

simultaneously extending and retracting the support rib relative to both the inlet stator and the outlet stator using a power supply.

16. The method of pumping fluid as defined in claim 13, wherein engaging each of a plurality of linear motors with a respective rib further comprises:

pivotally attaching the stator to one of the inlet end cap and the outlet end cap; and

securing one end of the support rib to the other of the inlet end cap and the outlet end cap; and

moveably engaging an opposing end of the rib with the respective stator.

17. The method of pumping fluid as defined in claim 13, further comprising:

forming each support rib wherein a circumferential width of each support rib is significantly less than a radial thickness of the respective support rib, such that circumferential deflection is minimized during radial movement of the rib.

18. The method of pumping fluid as defined in claim 13, further comprising:

forming the flexible generally tubular bladder with a generally hour-glass shape when in a resting position, such that the bladder exerts a radially inward bias when an axially central portion is expanded radially outward.

19. The method of pumping fluid as defined in claim 18, further comprising:

forming each of the plurality of support ribs as a relatively straight member when in a resting position, such that each of the plurality of support ribs exerts an outward bias that opposes the inward bias of the bladder when the respective support rib is moved radially inward.

20. The method of pumping fluid as defined in claim 18, further comprising:

securing the pump frame to a vessel to propel the vessel through a fluid.

21. The method of pumping fluid as defined in claim 13, further comprising:

positioning each of the plurality of linear motors radially outward of the bladder.

22. The method of pumping fluid as described in claim 13, further comprising:

connecting a plurality of connectors to one of the bladder and the support rib, each connector having an enlarged end, and

providing an elongate slot in the other of the bladder and the support rib for receiving the enlarged end of each of the plurality of connectors, such that the connectors may move along the elongate slot.