Fluid Flow Regulator

Abstract

A fluid flow regulator (10) comprising: a valve chamber (12) having a fluid inlet (14a) and a fluid outlet (14b); and a valve member (16) inside the valve chamber (12), the valve member (16) moveable inside the valve chamber (12); wherein the valve member (16) is concave in the direction of the fluid inlet and convex in the direction of the fluid outlet.

Claims

1. A fluid flow regulator comprising: a valve chamber having a fluid inlet and a fluid outlet; and a valve member inside the valve chamber, the valve member moveable inside the valve chamber, wherein the valve member is concave.

2. The fluid flow regulator according to claim 1, wherein the valve member is dish shaped.

3. The fluid flow regulator according to claim 1, wherein the valve member is concave in the direction of the fluid inlet and convex in the direction of the fluid outlet.

4. The fluid flow regulator according to claim 1, wherein the valve member is movable under the influence of pressure of the fluid inside the valve chamber to and from a valve seat, defining a flow opening there between, and arranged to adjust the size of the flow opening in dependence of the pressure of the fluid and/or flow rate.

5. The fluid flow regulator according to claim 1, wherein the valve member is substantially circular.

6. The fluid flow regulator according to claim 5, wherein the radius of the valve member is from 3.5 to 10 mm.

7. (canceled)

8. The fluid flow regulator according to claim 1, wherein there is a valve seat inside the valve chamber, the valve member is moveable inside the valve chamber and contactable with the valve seat, the valve seat having a width of from 1.75 to 2.25 mm.

9. (canceled)

10. The fluid flow regulator according to claim 1, wherein the valve member is deformable, such that in use the shape of the valve member is changeable.

11. The fluid flow regulator according to claim 1, wherein the valve member is concave such that the perpendicular distance from a line parallel with a lowermost surface of the convex side of the valve member and an uppermost edge of the concave side of the valve member is from 0.005 to 0.1 mm, more than the average thickness of the valve member.

12. (canceled)

13. The fluid flow regulator according to claim 11, wherein the valve member comprises a tab for locating the valve member inside the chamber, the tab being locatable with a portion of the valve chamber and the lowermost surface of the valve member is at a mid-point between an outermost surface of the tab and an opposing outmost edge of the valve member.

14. The fluid flow regulator according to claim 1, wherein the average thickness of the valve member is from 0.1 to 2.5 mm.

15. The fluid flow regulator according to claim 14, wherein the average thickness of the valve member is 0.35 to 0.4 mm.

16. The fluid flow regulator according to claim 1, wherein the lowermost surface of the valve member has an asymmetrical height distribution wherein a first edge portion of the valve member is located out of the plane of a second edge portion opposite the first edge portion of the valve member.

17. The fluid flow regulator according to claim 16, wherein the valve member comprises a tab for locating the valve member inside the chamber, the tab being locatable with a portion of the valve chamber, wherein seen in a cross-sectional plane perpendicular to a line between an outermost surface of the tab and an opposing outmost edge of the valve member, the lowermost surface of the valve member has an asymmetrical shape.

18. The fluid flow regulator according to claim 1, wherein the valve member is movable relative to a valve seat defining a flow opening there between, wherein at least in a resting position, a distance between a first edge of the valve member and the valve seat is different from a distance between a second edge opposite the first edge of the valve member and the valve seat.

19. The fluid flow regulator according to claim 16, wherein a height difference between the lowermost surface of the valve member at a first edge and a second edge opposite the first edge is 0.005 to 0.1 mm.

20. The fluid flow regulator according to claim 1, wherein the fluid flow regulator further comprises a non-return valve.

21. The fluid flow regulator according to claim 1, wherein the fluid flow regulator further comprises a pressure controller, the pressure controller at the fluid outlet of the fluid flow regulator and wherein in use, the pressure controller is used to control the pressure of fluid in the valve chamber, downstream of the valve member.

22. A method for manufacturing a fluid flow regulator according to claim 1, comprising the steps of: providing a valve member; shaping the valve member concave and/or forming a lowermost surface of the valve member to have an asymmetrical height distribution; providing a valve chamber of the fluid regulator; and assembling the valve member and the valve chamber for forming the fluid flow regulator.

23. The method according to claim 22, further comprising the steps of: determining a stiffness parameter of the valve member; and designing, based on the determined stiffness parameter, the concave shape and/or shape for the asymmetrical height distribution of the lower surface of the valve member prior to shaping the valve member.

Description

[0071] An embodiment of the present invention will now be described by way of example only and with reference to the accompanying drawings, in which:

[0072] FIG. 1 is a cross-sectional view of a fluid flow regulator;

[0073] FIG. 2 is a plan view of a valve member; and

[0074] FIG. 3 is a cross-sectional view of the valve member.

[0075] FIG. 4 is a cross-sectional view of fluid flow regulator along line IV in FIG. 1.

[0076] FIG. 1 shows a cross-sectional view of a fluid flow regulator 10. The fluid flow regulator 10 comprises a valve chamber 12 having a fluid inlet 14a and a fluid outlet 14b. There is a valve member 16 inside the valve chamber 12. The valve member 16 is moveable inside the valve chamber 12 and contactable with a valve seat 18 inside the valve chamber 12. Importantly, the valve member 16 is concave in shape. FIG. 1 does not show fluid in the fluid flow controller 10.

[0077] The fluid flow regulator 10 may be referred to as a dynamic fluid flow regulator. That is because the valve member 16 is moveable relative to the valve chamber 12. This contrasts with widely available pressure-fall dependent fluid flow regulators.

[0078] The fluid flow regulator 10 includes a strainer 20 at the top or fluid inlet 14a of the fluid flow regulator. The fluid flow regulator 10 includes a non-return valve 22 and resistance controller 29 at the bottom or fluid outlet 14b of the fluid flow regulator. The non-return valve 22 may be referred to as a check valve. The strainer 20 has a pin 21 that helps to keep the valve member 16 in the valve chamber 12.

[0079] The strainer 20 at the top or fluid inlet 14a of the fluid flow regulator 10 helps to stop larger solid particles from entering the valve chamber 12. The holes in the resistance controller 29 at the bottom or fluid outlet 14b of the fluid flow regulator 10 are larger than the holes in the strainer 20 at the top or fluid inlet 14a of the fluid flow regulator, so that solid particles do not accumulate in the fluid flow regulator 10. Solid particles that get into the fluid flow regulator 10 typically therefore also come out.

[0080] The valve member 16 is concave in the direction of the fluid inlet 14a and convex in the direction of the fluid outlet 14b.

[0081] In use, the valve member 16 moves inside the valve chamber 12 and is contactable with the valve seat 18 inside the valve chamber. The valve member 12 is moveable relative to the valve seat 18.

[0082] The valve seat 18 preferably has a radial width 19 of 1.97 mm.

[0083] In use, the resistance controller 29 is used to control or influence the backpressure of fluid (not shown) in the valve chamber. The resistance controller 29 restricts the flow of fluid out of the valve chamber 12 to create a higher backpressure.

[0084] In use, fluid (not shown) enters the valve chamber 12 and pushes down on the valve member 16. Some fluid flows past the valve member 16 and valve seat 18, flowing through the gap 26 between the valve member 16 and valve seat 18. Because of restricted fluid flow through the fluid flow regulator 10 downstream of the valve member 16, for instance caused by the resistance controller 29 some of the fluid (not shown) that has flowed past the valve member 16 and valve seat 18, pushes back against the valve member 16, against the overall direction of fluid flow, shown by the arrow 30, because of the shape of the seat. The greater the fluid force and pressure on the upstream side of the valve member 16, the greater the fluid support from the downstream side of the valve member. If the fluid force and pressure on the upstream side of the valve member 16 is reduced, the fluid support from the downstream side of the valve member is also reduced.

[0085] The arrow 30 shows the overall direction of the flow of fluid and the longitudinal axis of the valve chamber 12.

[0086] The valve member 16 has a tab 28 (see also FIG. 2) that is used to locate the valve member inside the chamber 12. The valve member 16 also has an aperture 32 in it for positioning the valve member inside the valve chamber 12. The valve chamber 12 has a post 34, the aperture 32 in the valve member 16 is located over the post 34. That is the post 34 is passable through the aperture 32 when the valve member 16 is inside the valve chamber 12.

[0087] FIG. 2 is a plan view of a valve member 16, of preferably the 7.8 L/min version, of the fluid flow regulator according to the present invention. An outer edge 16a of the valve member 16 is substantially circular. The radius of the valve member is preferably 6.97 mm FIG. 2 shows the concave face of the valve member 16 that faces the inlet (i.e. is in the direction of and/or adjacent to the fluid inlet). The convex face of the valve member 16 that faces the outlet (i.e. is in the direction of and/or adjacent to the fluid outlet) is not shown. The lowermost surface or lowermost point of the valve member 16 is at a mid-point 16d on line A between an outermost surface of the tab of the valve member and an opposing outmost edge 16h of the valve member 16.

[0088] FIG. 3 is a cross-sectional view along line A in FIG. 2 of the valve member 16, of preferably the 7.8 L/min version, of the fluid flow regulator according to the present invention. The average thickness of the valve member is preferably 0.392 mm±0.02 mm. The valve member 16 is curved such that the perpendicular distance 16e from a line parallel with a lowermost surface 16c of the convex side of the valve member that faces the outlet and an uppermost edge 16b of the concave side of the valve member that faces the inlet is preferably 0.39 mm, which is, preferably 0.02 mm, more than the average thickness of preferably 0.37 mm of the valve member.

[0089] FIG. 4 shows a cross-sectional view along arrows IV in FIG. 1. In this figure, it is visible that the lower surface of the valve member 16 is formed asymmetrical, seen in a plane perpendicular to the line A (between tab 28 and opposite edge 16h) in FIG. 3, wherein line A can be seen as a line of substantial mirror symmetry of the respective valve seat. That it, the lower surface at a first edge portion 16f (see also FIG. 2) is located out of the plane of the lower surface at a second edge portion 16g. Edge portion 16g is located lower than edge portion 16f. The distance d2 between the lower surface of the valve member 16 at the edge portion 16g and the valve seat 18 is thus smaller than the distance d1 between the lower surface of the valve member 16 at the edge portion 16f and the valve seat 18. The difference between distance d1 and d2 is preferably 0.03 mm in this example.

[0090] It is further visible that the valve seat 18 is provided with protrusions 18a which protrude from the surface of the valve seat 18. Protrusions 18a limit movement of the valve member 16 towards the valve seat 18 and ensure that a flow opening 26 between valve member 16 and valve seat 18 will remain. The protrusions 18a extend in the same cross-sectional plane as shown in FIG. 4. Multiple pairs of protrusions may be arranged, each pair extending in a plane parallel to the plane as shown in FIG. 4, i.e. a plane substantially perpendicular to the line A in FIG. 2. In use, when the valve member 16 bends due to an increased fluid pressure, the opposite edge 16h (see FIG. 2) will have the greatest travel length, edge portions 16f and 16g will contact the symmetrically arranged protrusions 18a valve seat 18 at different pressures due to asymmetrical (with respect to line A) lower surface of the valve member 16. This will reduce the occurrence of vibrations, which could otherwise occur when the valve member 16 would contact the protrusions 18a at substantially equal pressures.

[0091] Modifications and improvements can be incorporated herein without departing from the scope of the invention.