Pre-Biased Membrane Valve

• US 20130317413A1
• Filed: 05/23/2012
• Published: 11/28/2013
• Est. Priority Date: 05/23/2012
• Status: Active Grant

• Current Assignee: Alcon Research, LLC (Alcon Incorporated)
• Original Assignee: Robert Joseph Jr. Sanchez
• Inventors: Sanchez, Robert Joseph Jr., Rickard, Matthew J.A., Field, Leslie A.
• Granted Patent: US 8,858,491 B2
• Time in Patent Office: Days
• US Class Current: 604/9
• CPC Class Codes: A61F 2250/0014 having different values of a given property or geometrical feature, e.g. mechanical property or material property, at different locations within the same prosthesis
• CPC Class Codes: A61F 9/00781 Apparatus for modifying intraocular pressure, e.g. for glaucoma treatment drainage implants in general A61M27/002
• CPC Class Codes: A61M 2039/242 designed to open when a predetermined pressure or flow rate has been reached, e.g. check valve actuated by fluid
• 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: Y10T 137/7879 Resilient material valve
• CPC Class Codes: Y10T 29/494 Fluidic or fluid actuated device making

Abstract

A method of manufacturing a valve for a fluid system is described herein. The method comprises determining a target cracking pressure for the valve of the fluid system, providing an inner wall having a first height and an outer wall having a second height, the first height varying from the second height by a height differential, and attaching a flexible membrane to the outer wall at the second height, wherein a central zone of the flexible membrane is in contact with the inner wall at the first height and the inner wall biases the flexible membrane from a neutral condition. The height differential is selected to provide resistance to displacement from the inner wall until pressure acting on the membrane exceeds the target cracking pressure.

Claims

1. A method of manufacturing an implantable valve for a fluid system comprising:

determining a target cracking pressure for the valve of the fluid system;

providing an inner wall having a first height and an outer wall having a second height, the first height varying from the second height by a height differential; and

attaching a flexible membrane to the outer wall at the second height so that a central zone of the flexible membrane contacts the inner wall at the first height, the inner wall biasing the flexible membrane from a neutral condition, the height differential being selected to provide resistance to displacement from the inner wall until pressure acting on the membrane exceeds the target cracking pressure.

2. The method of claim 1, wherein a peripheral zone of the flexible membrane is anchored within the valve between the outer wall and a membrane housing portion.

3. The method of claim 1, wherein the inner wall defines a fluid inlet spanned by the flexible membrane, the height differential taking into account the diameter of the fluid inlet to achieve a balance between fluid inlet diameter and resistance to deflection to achieve the target cracking pressure.

4. The method of claim 3, wherein the inner wall includes a valve seat disposed in a manner that selectively contacts the central zone of the flexible membrane and seals the fluid inlet when the target cracking pressure exceeds pressure acting on the membrane.

5. The method of claim 4, wherein the flexible membrane is anchored within the valve to form a reference chamber on a first side of the flexible membrane and a fluid flow channel on a second opposing side of the membrane, the reference chamber having a reference chamber pressure, the flexible membrane being configured to flex and selectively open and close the fluid flow channel to permit fluid to flow from the fluid inlet to a fluid outlet, the membrane configured to control flow through the fluid flow channel from the fluid inlet to the fluid outlet by deflecting from the valve seat in response to pressure differentials of the reference chamber pressure and a fluid flow channel pressure acting on the first and second opposing sides of the flexible membrane.

6. A method of manufacturing a plurality of implantable valves having different predetermined target cracking pressures, comprising:

manufacturing a first valve of the plurality of implantable valves, comprising;

attaching a first flexible membrane to a first anchoring location at a first height on a first outer wall so that a central zone of the first flexible membrane contacts a first inner wall at a first inner wall height, in a manner that the first inner wall biases the first flexible membrane from a neutral condition, the first height varying from the first inner wall height by a first height differential selected so that the first membrane resists displacement from the first inner wall until pressure acting on the first membrane exceeds a first cracking pressure; and

manufacturing a second valve of the plurality of implantable valves, comprising;

attaching a second flexible membrane to a second anchoring location at a second height on a second outer wall so that a central zone of the second flexible membrane contacts a second inner wall at a second inner wall height, in a manner that the second inner wall biases the second flexible membrane from a neutral condition, the second height varying from the second inner wall height by a second height differential selected so that the second membrane resists displacement from the second inner wall until pressure acting on the second membrane exceeds a second cracking pressure,

wherein first and second flexible membranes have substantially the same structural configuration and elastic properties, and wherein the first height differential differs from the second height differential such that the cracking pressure of the first valve is different than the cracking pressure of the second valve.

7. The method of claim 6, wherein the first valve and the second valve are sized for implantation in an eye.

8. The method of claim 6, further comprising:

attaching a drainage tube to a passage through the first inner wall, the passage being oriented so that the passage is substantially perpendicular to the flexible membrane.

9. The method of claim 6, wherein the first inner wall forms a boss.

10. The method of claim 6, wherein attaching the first flexible membrane includes clamping edges of the flexible membrane to a top portion of the outer wall.

11. The method of claim 6, wherein the first inner wall defines a first fluid inlet spanned by the first flexible membrane and the second inner wall defines a second fluid inlet spanned by the second flexible membrane, the first and second height differentials taking into account the diameters of the first and second fluid inlets, respectively, to achieve a balance between fluid inlet diameter and resistance to deflection to achieve desired cracking pressures.

12. A valve for a fluidic system having a predetermined target cracking pressure, comprising:

a housing including a fluid inlet, a fluid outlet, and a one-piece orifice portion including an inner wall having a first height and an outer wall having a second height, the first height being different than the second height by a height differential, the outer wall being disposed about the inner wall; and

a flexible membrane anchored within the housing to form a reference chamber on a first side of the flexible membrane and a fluid flow channel on a second opposing side of the membrane, the reference chamber having a reference chamber pressure, the flexible membrane being configured to flex and selectively open and close the fluid flow channel to permit fluid to flow from the fluid inlet to the fluid outlet, the flexible membrane configured to control flow through the fluid flow channel from the fluid inlet to the fluid outlet by deflecting in response to pressure differentials of the reference chamber pressure and the fluid flow channel pressure acting on the first and second opposing sides of the flexible membrane,

wherein the inner wall includes a valve seat disposed in a manner that selectively contacts a central zone of the flexible membrane and seals the fluid inlet with a central zone of the flexible membrane, wherein the height differential displaces the membrane from a neutral condition to a biased condition, resulting in the valve having the predetermined target cracking pressure.

13. The valve of claim 12, the housing further including a membrane portion, wherein a peripheral zone of the flexible membrane is anchored between the membrane portion and the outer wall.

14. The valve of claim 12, wherein the first height of the inner wall is greater than the second height of the outer wall.

15. The valve of claim 12, wherein the first height of the inner wall is less than the second height of the outer wall.

16. The valve of claim 12, wherein the flexible membrane is anchored to the housing in a valve-closed position when the pressure differential is zero.

17. The valve of claim 12, wherein the fluid flow channel comprises a gap between the valve seat and the flexible membrane.

18. The valve of claim 12, wherein the flexible membrane comprises a flexible, fluid-tight membrane configured to deflect away from the valve seat in response to an elevated pressure.

19. The valve of claim 18, wherein the flexible membrane comprises a circular membrane.

20. The valve of claim 12, wherein the flexible membrane is configured to control flow through the fluid flow channel by deflecting in response to pressure differentials between an anterior chamber of the eye and atmospheric pressure acting on the flexible membrane.