Method of making a membrane for use with a flow control system for a micropump

• US 8,663,538 B2
• Filed: 06/30/2011
• Issued: 03/04/2014
• Est. Priority Date: 02/12/2009
• Status: Active Grant

• Current Assignee: PicoLife Technologies, LLC
• Original Assignee: PicoLife Technologies, LLC
• Inventors: Amirouche, Farid, Cantwell, Matthew
• Primary Examiner(s): Gupta, Yogendra
• Assistant Examiner(s): HINDENLANG, ALISON L
• Application Number:
  US13/174,643
• Publication Number:
  US 20110309552A1
• Time in Patent Office: 978 Days
• Field of Search: 264/331.11
• US Class Current: 264/331.11
• CPC Class Codes: A61M 2039/2453 not being fixed to the valve body
• CPC Class Codes: A61M 2205/0244 Micromachined materials, e.g. made from silicon wafers, microelectromechanical systems [MEMS] or comprising nanotechnology
• CPC Class Codes: A61M 39/24 Check- or non-return valves
• CPC Class Codes: A61M 5/1422 with double acting or multiple pistons
• CPC Class Codes: A61M 5/14224 Diaphragm type
• CPC Class Codes: A61M 5/16804 Flow controllers
• CPC Class Codes: F04B 43/043 Micropumps
• CPC Class Codes: Y10T 137/7879 Resilient material valve
• CPC Class Codes: Y10T 137/86002 Fluid pressure responsive
• CPC Class Codes: Y10T 137/86019 Direct response valve
• CPC Class Codes: Y10T 29/49996 Successive distinct removal operations

Abstract

A method of making a membrane for use with a flow control system is disclosed. A female mold body portion and a male mold body portion are provided. A body portion support member configured to receive at least a portion of the female body portion and at least a portion of the male body portion is provided. The female and male body portions are separated from one another Membrane manufacturing material is provided to a concave portion of the female mold body portion. The sleeve is moved downward. The lower mold portion is lowered until it is just short of its final intended position. Excess membrane manufacturing material, if any, is removed from around the seam of the mold. The upper mold portion is lowered the remaining distance so that the two mold portions are separated by the exact distance desired for the final membrane thickness.

Claims

1. A method of making a membrane having a reinforcement annulus for use with a flow control system, the method comprising:

providing a mold female body portion having a cylindrical elongate lower portion extending along an axis and having a first diameter, and a centered, concave upper face having a second diameter that is substantially equal to the first diameter and having a first radius of curvature, the upper face being oriented substantially perpendicularly to the axis of the elongate lower portion;

providing a male mold body portion having a cylindrical elongate upper portion with a lower terminus extending along an axis, the upper portion thereof having a third diameter substantially equal to the first diameter and a central cylindrical portion having a height extending from the lower terminus along the axis of the upper portion, the central portion has a fourth diameter and a spacing gap having an annular width extending radially outward from the central portion, wherein the fourth diameter is substantially equal to the first diameter minus the annular width of the spacing gap on each side, the male mold body portion further having a centered, convex lower face having a fifth diameter substantially equal to the fourth diameter and a second radius of curvature substantially equal to the first radius of curvature, and the lower face being oriented substantially perpendicularly to the axis of the elongate upper portion;

moving the male body portion to within a predetermined distance from the female body portion;

providing a body portion support member having a generally elongated, tubular configuration and further having an inner diameter slightly greater than the first diameter, the body portion support member being configured to receive at least a portion of the female body portion and at least a portion of the male body portion, so that the female and male body portions are maintainable along the same axis and the convex face and concave face are positioned in cooperative relation with one another;

separating the female and male body portions from one another and lubricating each with a lubricant;

providing a predetermined amount of membrane manufacturing material to the concave face of the lower portion of the female mold body portion;

covering the area between the male and female mold body portions with the body portion support member;

dropping the male mold body portion until it is 0.005″

short of its final intended position;

removing any excess membrane manufacturing material from around the area between the male and female mold body portions;

dropping the male mold body portion the remaining distance so that the two mold portions are separated by the distance desired for the final membrane thickness to cooperatively effect manufacture of the membrane having a reinforcement annulus along a periphery of the membrane, wherein the width of the reinforcement annulus substantially equals the annular width of the spacing gap;

heating the assembly to a predetermined temperature for a first predetermined length of time;

allowing the assembly to cool for a second predetermined length of time; and

removing the membrane.

2. The method of making a membrane of claim 1, wherein the first diameter is about 0.25 inches and the annular width is about 0.025 inches.

3. The method of making a membrane of claim 1, wherein the first diameter is about 0.1875 inches and the annular width is about 0.020 inches.

4. The method of making a membrane of claim 1, wherein the premixed membrane manufacturing material is an elastomer.

5. The method of making a membrane of claim 1, wherein the premixed membrane manufacturing material contains silicone.

6. The method of making a membrane of claim 1, wherein the premixed membrane manufacturing material is an enhanced-tear-resistant silicone elastomer.

7. The method of making a membrane of claim 1, wherein the premixed membrane manufacturing material is further prepared by mixing it in a prescribed ratio of a base to a reagent and allowing it to sit for a third predetermined time sufficient to allow the substantial majority of air bubbles to exit the surface.

8. The method of making a membrane of claim 7, wherein the prescribed ratio of base to reagent is about 10:

1.

9. The method of making a membrane of claim 8, wherein the third predetermined time is about ten minutes.

10. The method of making a membrane of claim 7, wherein the prescribed ratio of base to reagent is about 1:

1.

11. The method of making a membrane of claim 10, wherein the third predetermined time is about ten minutes.

12. The method of making a membrane of claim 7, wherein the third predetermined time is about ten minutes.

13. The method of making a membrane of claim 1, wherein the annular width is about 0.010 inches.

14. The method of making a membrane of claim 1, wherein the annular, width is about 0.015 inches.

15. The method of making a membrane of claim 1, wherein the annular width is about 0.013 inches.

16. The method of making a membrane of claim 1, wherein the lubricant is silicone.

17. The method of making a membrane of claim 1, wherein the predetermined temperature is about 300 F and the first predetermined length of time is about 14 minutes.

18. The method of making a membrane of claim 1, wherein the predetermined temperature is about 302 F, and the first predetermined length of time is about 5 minutes.

19. The method of making a membrane of claim 1, wherein the second predetermined length of time is about two minutes.

20. A method of making a membrane having a reinforcement annulus for use with a flow control system, the method comprising:

providing a mold female body portion having a cylindrical elongate lower portion extending along an axis and having a first diameter equal to about 0.1875 inches, and a centered, concave upper face having a second diameter that is substantially equal to the first diameter and having a first radius of curvature, the upper face being oriented substantially perpendicularly to the axis of the elongate lower portion and extending therefrom, in a substantially vertical, upwardly extending position;

providing a male mold body portion having a cylindrical elongate upper portion with a lower terminus extending along an axis, the upper portion thereof having a third diameter substantially equal to the first diameter and a central cylindrical portion having a height extending from the lower terminus along the axis of the upper portion, the central portion has a fourth diameter and a spacing gap having an annular width of about 0.020 inches extending radially outward from the central portion, wherein the fourth diameter is substantially equal to the first diameter minus the annular width of about 0.020 inches on each side, the male mold body portion further having a centered, convex lower face having a fifth diameter substantially equal to the fourth diameter and a second radius of curvature substantially equal to the first radius of curvature, and the lower face being oriented substantially perpendicularly to the axis of the elongate upper portion;

moving the male body portion downwardly to within a predetermined distance from the female body portion, wherein the predetermined distance is about 0.013 inches;

providing a body portion support member having a generally elongated, tubular configuration and further having an inner diameter slightly greater than the first diameter, the body portion support member being configured to receive at least a portion of the female body portion and at least a portion of the male body portion, so that the female and male body portions are maintainable along the same axis and the convex face and concave face are positioned in cooperative relation with one another;

separating the female and male body portions from one another and lubricating each with a silicone lubricant;

premixing a predetermined amount of membrane manufacturing material in a ratio of 1;

1 base to reagent and allowing it to sit for about ten minutes;

providing the predetermined amount of the premixed membrane manufacturing material to the concave face of the lower portion of the female mold body portion;

covering the area between the male and female mold body portions with the body portion support member;

dropping the male mold body portion until it is about 0.005 inches short of its final intended position;

removing any excess membrane manufacturing material from around the area between the male and female mold body portions;

dropping the male mold body portion the remaining distance so that the two mold portions are separated by the exact distance desired for the final membrane thickness and to cooperatively effect manufacture of the membrane having a reinforcement annulus along a periphery of the membrane, wherein the width of the reinforcement annulus substantially equals the annular width of the spacing gap;

heating the assembly to a temperature of about 302 F for about 5 minutes;

allowing the assembly to cool for about two minutes; and

removing the membrane.

21. A method of making a membrane having a reinforcement annulus for use with a flow control system, the method comprising:

providing a mold female body portion having a cylindrical elongate lower portion extending along an axis and having a first diameter, and a centered, concave upper face having a second diameter that is substantially equal to the first diameter and having a first radius of curvature, the upper face being oriented substantially perpendicularly to the axis of the elongate lower portion;

providing a male mold body portion having a cylindrical elongate upper portion with a lower terminus extending along an axis, the upper portion thereof having a third diameter substantially equal to the first diameter and a central cylindrical portion having a height extending from the lower terminus along the axis of the upper portion, the central portion has a fourth diameter and a spacing gap having an annular width extending radially outward from the central portion, wherein the fourth diameter is substantially equal to the first diameter minus the annular width of the spacing gap on each side, the male mold body portion further having a centered, convex lower face having a fifth diameter substantially equal to the fourth diameter and a second radius of curvature substantially equal to the first radius of curvature, and the lower face being oriented substantially perpendicularly to the axis of the elongate upper portion;

providing a body portion support member having a generally elongated, tubular configuration and further having an inner diameter slightly greater than the first diameter, the body portion support member being configured to receive at least a portion of the female body portion and at least a portion of the male body portion, so that the female and male body portions are maintainable along the same axis and the convex face and concave face are positioned in cooperative relation with one another;

providing a predetermined amount of membrane manufacturing material to at least one of the concave upper face and the convex lower face;

positioning the body support portion to receive at least a portion of the female body portion and at least a portion of the male body portion; and

moving the male and female mold body portions within a predetermined distance from each other to cooperatively effect manufacture of the membrane having a reinforcement annulus along a periphery of the membrane, wherein the width of the reinforcement annulus substantially equals the annular width of the spacing gap, and wherein the predetermined distance between the two mold portions corresponds to a thickness of the membrane.