Miniature Pump Device with an Anti-Free Flow Valve

• US 20100135831A1
• Filed: 10/22/2009
• Published: 06/03/2010
• Est. Priority Date: 10/22/2008
• Status: Active Grant

• Current Assignee: Jacobsen Innovations Inc.
• Original Assignee: Sterling Investments LC
• Inventors: Jacobsen, Stephen C.
• Granted Patent: US 8,696,336 B2
• Time in Patent Office: Days
• US Class Current: 417/415
• CPC Class Codes: A61M 2039/2413 designed to reduce and or shut-off the flow when a certain maximum flow limit is exceeded
• CPC Class Codes: A61M 39/24 Check- or non-return valves
• CPC Class Codes: A61M 39/281 Automatic tube cut-off devices, e.g. squeezing tube on detection of air
• CPC Class Codes: A61M 5/14216 Reciprocating piston type
• CPC Class Codes: A61M 5/14276 specially adapted for implantation
• CPC Class Codes: A61M 5/16881 Regulating valves on-off valves, e.g. clamps A61M39/28
• CPC Class Codes: F04B 19/006 Micropumps F04B43/043 and F04B43/095 take precedence
• CPC Class Codes: F04B 23/02 having reservoirs
• CPC Class Codes: F04B 53/10 Valves; Arrangement of valves
• CPC Class Codes: F16K 7/17 the diaphragm being actuated by fluid pressure
• CPC Class Codes: Y10T 137/7836 Flexible diaphragm or bellows reactor

Abstract

A miniature unidirectional valve configured to restrict the free flow of fluid through the valve includes a valve body having an inlet and an outlet. A flexible membrane is movably disposed over the inlet and outlet, and movable between an open position and a closed position. The flexible membrane is movable by a pressure from the inlet to move the membrane to the open position. A control chamber is disposed in the valve body adjacent the fluid flow path, and configured to apply a pressure against the membrane to move the membrane to the closed position to restrict fluid flow through the valve. A preload structure is associated with the flexible membrane, and biases the flexible membrane toward the closed position.

Claims

1. A miniature unidirectional valve configured to restrict the free flow of fluid through the valve, comprising:

a valve body having an inlet and an outlet;

a flexible membrane movably disposed over the inlet and outlet, and movable between an open position with the membrane defining an unobstructed fluid flow path between the inlet and outlet, and a closed position with the membrane sealing the outlet to restrict fluid flow therethrough;

a control chamber disposed in the valve body adjacent the fluid flow path and separated from the fluid flow path by the flexible membrane, the control chamber being configured to apply a pressure against the membrane to move the membrane to the closed position against the outlet to restrict fluid flow therethrough;

a preload structure, associated with the flexible membrane, and configured to bias the flexible membrane towards the outlet to close the outlet and restrict fluid flow therethrough,

the flexible membrane being movable by a pressure from the inlet to move the membrane to the open position to open the outlet and permit fluid flow.

2. A valve in accordance with claim 1, wherein the preload structure includes a protrusion extending into the control chamber, which operates to stretch the flexible membrane toward the outlet to seal against the edges of the outlet.

3. A valve in accordance with claim 1, wherein the preload structure operates to bias the flexible membrane into the outlet such that the flexible membrane closes the outlet in the presence of a negative pressure in the outlet.

4. A valve in accordance with claim 1, wherein the control chamber is in fluid communication with a fluid reservoir.

5. A valve in accordance with claim 4, wherein the flexible membrane operates to move to the closed position when the pressure from the fluid in the fluid reservoir exceeds the pressure from fluid in the inlet.

6. A valve in accordance with claim 4, wherein the flexible membrane operates to move to the open position when the pressure from fluid in the fluid inlet exceeds the pressure from the fluid in the fluid reservoir.

7. A valve in accordance with claim 1, wherein the flexible membrane is an elastomeric sheet disposed across opposing wall segments within the valve body to form the control chamber in a first portion of the valve body on a first side of the elastomeric sheet and the fluid flow path in a second portion of the valve body on a second side of the elastomeric sheet, wherein the elastomeric sheet forms a seal between the control chamber and the fluid flow path to restrict fluid communication therebetween.

8. A miniature pump device with an anti-free flow valve, comprising:

a fluid reservoir;

a motor, configured to electrically couple to a power source, and disposed adjacent the fluid reservoir;

a piston, disposed in the fluid reservoir, and operable with the motor to draw and expel fluid from the fluid reservoir;

a power transfer linkage, coupled between the piston and the motor, partially disposed in the fluid reservoir, and configured to transfer power from the motor to the piston;

a flexible seal, coupled between the fluid reservoir and the power transfer linkage, configured to seal a portion of the power transfer linkage in the fluid reservoir and restrict fluid from escaping from fluid reservoir as the power transfer linkage moves during use; and

an anti-free flow valve operable to receive fluid as pumped by the piston, the anti-free flow valve operating to restrict fluid from reentering the piston, the anti-free flow valve further comprising;

a valve body having an inlet and an outlet;

a flexible membrane movably disposed over the inlet and outlet, and movable between an open position with the membrane defining an unobstructed fluid flow path between the inlet and outlet, and a closed position with the membrane sealing the outlet to restrict fluid flow therethrough;

a control chamber disposed in the valve body adjacent the fluid flow path and separated from the fluid flow path by the flexible membrane, the control chamber being in fluid communication with the fluid reservoir, and configured to apply a pressure against the membrane to move the membrane to the closed position against the outlet to restrict fluid flow therethrough;

the flexible being membrane movable by a pressure from the inlet to move the membrane to the open position to open the outlet and permit fluid flow.

9. A device in accordance with claim 8, further comprising a preload structure associated with the flexible membrane, and configured to bias the flexible membrane towards the outlet to close the outlet and restrict fluid flow therethrough, wherein the preload structure includes a protrusion in the control chamber configured to press the flexible membrane against the outlet.

10. A device in accordance with claim 9, wherein the preload structure operates to bias the flexible membrane into the outlet such that the flexible membrane closes the outlet in the presence of a negative pressure in the outlet.

11. A device in accordance with claim 8, wherein the control chamber is subject to pressure from fluid in the fluid reservoir.

12. A device in accordance with claim 11, wherein the flexible membrane operates to move to the closed position when the pressure from the fluid in the fluid reservoir exceeds the pressure from fluid in the inlet.

13. A device in accordance with claim 11, wherein the flexible membrane is operates to move to the open position when the pressure from fluid in the fluid inlet exceeds the pressure from the fluid in the fluid reservoir.

14. A device in accordance with claim 8, wherein the flexible membrane further comprises an elastomeric sheet disposed within the valve body to form the control chamber in a first portion of the valve body on a first side of the elastomeric sheet and the fluid flow path in a second portion of the valve body on a second side of the elastomeric sheet, wherein the elastomeric sheet forms a seal between the control chamber and the fluid flow path to restrict fluid communication therebetween.

15. A device in accordance with claim 8, wherein the flexible seal further comprises:

an elastomeric plug, disposed in a wall of the fluid reservoir with a portion of the power transfer linkage extending through the elastomeric plug,

the elastomeric plug being bonded to the power transfer linkage to form a seal thereon, and configured to elastically flex with the power transfer linkage as the power transfer linkage moves during use.

16. A device in accordance with claim 15, wherein a portion of the flexible seal stretches on one side of the power transfer linkage and a portion compresses on an opposite side of the power transfer linkage.

18. A method in accordance with claim 16, wherein the step of opening the fluid flow path includes moving a fluid into the inlet.

19. A method in accordance with claim 16, wherein the step of closing the fluid flow path includes supplying pressure to the control chamber to press the flexible membrane against the outlet.

20. A method in accordance with claim 16, wherein the step of closing the fluid flow path includes supplying negative pressure to the outlet to draw the flexible membrane against the outlet.

21. A method in accordance with claim 16, wherein the preload structure includes a protrusion in the control chamber that operates to press the flexible membrane toward the outlet.

17. A method for restricting the free flow of fluid, comprising:

providing a valve body having an inlet, an outlet, and a flexible membrane disposed across the inlet and outlet, the flexible membrane defining a fluid flow path between the inlet and the outlet on one side of the flexible membrane, and a control chamber on an opposite side of the flexible membrane;

opening the fluid flow path with pressure from the inlet to move the flexible membrane to an open position such that flexible membrane defines an unobstructed fluid flow path between the inlet and outlet to allow fluid to flow between the inlet and the outlet;

closing the fluid flow path with a pressure against the flexible membrane to move the flexible membrane to a closed position such that the flexible membrane presses against and seals over the outlet to restrict fluid flow therethrough; and

biasing the flexible membrane toward the closed position with a preload structure such that closing the fluid flow path requires less pressure than opening the fluid flow path.

22. A miniature unidirectional valve configured to restrict the free flow of fluid through the valve, comprising:

a valve body having an inlet and an outlet;

a valve gate disposed in the valve body, operable between an open position defining an unobstructed fluid flow path between the inlet and outlet, and a closed position obstructing the outlet to restrict fluid flow therethrough;

a fluid reservoir in fluid communication with the valve gate such that pressure from the fluid reservoir operates to urge the valve gate towards the closed position; and

a biasing device associated with the valve gate to bias the valve gate to the closed position to restrict fluid flow therethrough,

wherein a pressure from the inlet operates on the valve gate to overcome the pressure from the fluid reservoir and the biasing device and to open the valve gate.

23. A valve in accordance with claim 22, the valve gate further comprising;

a flexible membrane movably disposed over the inlet and outlet, and movable between an open position with the membrane defining an unobstructed fluid flow path between the inlet and outlet, and a closed position with the membrane sealing the outlet to restrict fluid flow therethrough;

a control chamber disposed in the valve body adjacent the fluid flow path and separated from the fluid flow path by the flexible membrane, the control chamber being configured to apply a pressure against the membrane to move the membrane to the closed position against the outlet to restrict fluid flow therethrough; and

a preload structure, associated with the flexible membrane, and configured to stretch the flexible membrane against the outlet to close the outlet and restrict fluid flow therethrough,

the flexible membrane being movable by a pressure from the inlet to move the membrane to the open position.

24. A valve in accordance with claim 22, the valve gate further comprising;

a spool movably disposed over the inlet and outlet, and movable between an open position with the spool defining an unobstructed fluid flow path between the inlet and outlet, and a closed position with the spool sealing the outlet to restrict fluid flow therethrough;

a control chamber disposed in the valve body adjacent the fluid flow path and separated from the fluid flow path by the spool, the control chamber being configured to apply a pressure against the spool to move the spool to the closed position against the outlet to restrict fluid flow therethrough; and

a biasing member, associated with the spool, and configured to urge the spool towards the outlet to close the outlet and restrict fluid flow therethrough,

the spool being movable by a pressure from the inlet to move the spool to the open position to permit fluid flow through the outlet.