Fluid flow regulator

Abstract

The fluid flow regulator (10) comprises a valve chamber (12) having a fluid inlet (14a) and a fluid outlet (14b), and a valve member (16) within the valve chamber (12) and movable within the valve chamber (12), the valve member (16) preferably being concave in the direction of the fluid inlet and convex in the direction of the fluid outlet.

Description

[Technical Field]

[0001] FIELD OF THE INVENTION The present invention relates to fluid flow regulators, and generally to fluid flow regulators for regulating the flow of water. [Background technology]

[0002] To reduce water consumption, many water companies in Europe have been reducing the pressure in the mains. By doing so, they reduce water and energy consumption and reduce leakage from pipes. At the same time, the pressure of the water entering a building can drop at any time due to demand on the system.

[0003] Regulating fluid flow over a range of different pressures is particularly difficult, as many existing fluid flow regulators do not function properly over a range of different pressures, causing the fluid flow to vary too much to be effective. Summary of the Invention [Problem to be solved by the invention]

[0004] Considering the need to reduce water consumption and regulate fluid flow, the inventors of the present invention have devised an effective fluid flow regulator. [Means for solving the problem]

[0005] According to a first aspect of the present invention, there is provided a fluid flow regulator comprising a valve chamber having a fluid inlet and a fluid outlet, and a valve member within the valve chamber, the valve member being concave.

[0006] The valve member is typically concave in the direction of and / or adjacent to the fluid inlet and / or convex in the direction of and / or adjacent to the fluid outlet.

[0007] The fluid flow regulator may reliably and / or reproducibly regulate the flow of fluid when the pressure of the fluid supplied to the fluid inlet is between 1.5 and 10 bar. In use, the variation in the flow rate of the fluid exiting the fluid outlet should preferably be (on average) less than 2%, more preferably less than 1%, of the variation in the fluid pressure and / or flow rate of the fluid supplied to the fluid inlet.

[0008] Also, when increasing the pressure of the fluid supplied to the fluid inlet as it cycles from minimum to maximum and back to the minimum operating pressure, the variation in the flow rate of the fluid exiting the fluid outlet during the first increasing portion of the cycle should preferably be less than 5% (at any given pressure within the pressure range) when compared to the flow rate of the fluid exiting the fluid outlet during the second decreasing portion of the cycle. In other words, the flow regulator should preferably operate with this very low hysteresis, and preferably should operate substantially without hysteresis.

[0009] As noted above, the variation in the flow rate of fluid exiting the fluid outlet at any given fluid pressure should preferably be less than 5% when the fluid pressure is increasing compared to when the fluid pressure is decreasing. More preferably, the variation in the flow rate of fluid exiting the fluid outlet is less than 2%, and even more preferably less than 1%, when the fluid pressure is cycling between its upper and lower operating pressure limits, and vice versa. The upper limit can be a relatively high pressure, such as 5 bar or 10 bar, or anything in between. The lower limit can be a relatively low pressure, such as 1.5 bar or 2 bar, or anything in between.

[0010] The fluid flow regulator can therefore reliably and / or reproducibly regulate the flow of fluid when the pressure of the fluid supplied to the fluid inlet is preferably between 1.5 and 10 bar.

[0011] The pressures referred to herein are also generally referred to as dynamic fluid pressures and / or actuating fluid pressures. That is, the pressures referred to herein are generally dynamic fluid pressures rather than static fluid pressures. As previously mentioned, dynamic fluid pressures may also be referred to as actuating pressures.

[0012] Generally, the concave and / or convex shape of the valve member contributes to the relatively small fluctuations in fluid flow rate compared to known fluid flow regulators. The relatively small fluctuations in fluid flow rate may be excessively small fluctuations in fluid flow rate. The concave and / or convex shape of the valve member is primarily responsible for the increased pressure range over which the fluid flow regulator may provide at least substantially pressure-independent fluid flow. This at least substantially pressure-independent fluid flow may be practically pressure-independent fluid flow.

[0013] The concave valve member may be and / or be referred to as one or more of dished (ie, dish-shaped), curved, concave, recessed, sunken, indented, or textured.

[0014] Thus, the valve member is shaped to be concave in a rest position (or condition), i.e., when the fluid flow regulator is not in use. Thus, in this rest position, the valve member is concave in its initial, undeformed state. Disposing the movable valve member within the valve chamber is configured to adjustably restrict fluid flow through the valve chamber.

[0015] In use, the valve member defines a flow path and / or boundary between the fluid inlet and the fluid outlet. The fluid flow regulator may, for example, include a housing provided with the inlet and outlet and a valve chamber therebetween. The valve member is preferably disposed within the housing and is movable to and from the valve seat, defining a flow opening therebetween. The valve member is movable under the influence of fluid pressure and configured to adjust the size of the flow opening depending on the fluid pressure and / or flow rate, such that the liquid flow is substantially constant over a range of pressures. To ensure liquid flow through the opening even at high pressures, i.e., to prevent complete closure of the flow opening, the valve seat is preferably provided with at least one protruding member for limiting movement of the valve member toward the valve seat.

[0016] Fluid flow regulators typically regulate the flow of liquid, optionally water. In use, water typically flows through the fluid flow regulator. In use, water may flow through the fluid flow regulator at rates of 1.5 to 12 L / min, optionally 1.5 to 3.5 L / min; typically 2 to 3 L / min, 4 to 10 L / min, typically 7.5 to 8.5 L / min, up to a maximum of 50 L / min or more.

[0017] In use, the valve member moves relative to the valve chamber, preferably to and from the valve seat as described above, to provide fluid flow from the fluid outlet at a pressure and / or flow rate substantially independent of the pressure and / or flow rate of fluid supplied to the fluid inlet. At least substantially pressure-independent fluid flow can be practically pressure-independent fluid flow. In use, the pressure and / or flow rate of fluid from the fluid flow regulator typically fluctuates by 2% or less.

[0018] The outer edge of the valve member is generally partially or substantially circular. The radius of the valve member is generally 3.5 to 10 mm, usually 3.5 to 5 mm, and may be approximately 4 mm, usually 5 to 8 mm, approximately 7 mm, 6.97 mm, or at least 8 mm, usually 9 mm. Preferably, the valve seat has a corresponding shape.

[0019] The valve member may be disc-shaped or may be referred to as disc-shaped. The valve member is generally a movable obstruction within the valve chamber. The valve member is typically used to adjustably restrict the flow of fluid through the valve chamber.

[0020] In use, the valve member typically moves linearly within the valve chamber, preferably towards and away from the valve seat, and / or relative to the longitudinal axis of the valve chamber under the influence of fluid pressure and / or flow.

[0021] The valve member may include a tab for positioning the valve member within the valve chamber. The tab may be contactable with and / or positionable by a portion of the valve chamber. The valve member may have an opening therein for positioning the valve member within the valve chamber. The valve chamber may include a post, and the opening in the valve member may be generally positionable relative to the post. That is, the post may pass through the opening when the valve member is within the valve chamber.

[0022] The valve member is movable within the valve chamber and typically contacts a valve seat within the valve chamber. The valve member is typically movable relative to the valve seat. The tabs allow the valve member to pivot relative to the valve seat.

[0023] The valve seat may have a radial width greater than 1.5 mm, optionally greater than 1.75 mm, typically 1.97 mm, or between 1.75 and 2.25 mm.

[0024] The valve member is generally deformable, and may be elastically deformable, i.e., the shape of the valve member is changeable during use. A deformable valve member typically changes shape in response to the pressure and / or flow rate of a fluid in contact with it and / or the pressure and / or flow rate of a fluid supplied to a fluid inlet of the fluid flow regulator.

[0025] The characteristics of the valve member depend on its concave shape and deformability. A flat valve member cannot achieve the same characteristics. A flat valve member may not respond adequately to fluctuations in input fluid pressure. As a result, the output fluid pressure may fluctuate more than desired during use. A flat valve member may adequately control the outlet fluid pressure and / or flow rate when the input fluid pressure and / or flow rate are relatively high or relatively low, but may not adequately control when the input fluid pressure varies over a range of 1.5 to 10 bar. Adequate control generally means a stable outlet fluid pressure and / or flow rate.

[0026] The valve member of the present invention may be a spring and / or the behavior of the valve member in use may be described as spring-like.

[0027] The concave and / or convex shape of the valve member typically makes the fluid flow regulator suitable for operation at low and / or high fluid pressures and pressures therebetween. The concave and / or convex shape of the valve member typically makes the fluid flow regulator suitable for operation at low and / or high fluid temperatures.

[0028] Concave and / or convex valve members are typically stiffer and / or stronger and / or less flexible than flat valve members. The stiffer and / or stronger and / or less flexible concave and / or convex valve members may provide the advantage of better control of outlet fluid flow rates when the input fluid pressure is, for example, 1.5-10 bar. In use, at a dynamic fluid pressure of 1.5-10 bar, the flow rate is 4-10 L / min, optionally 7.5-8.5 L / min, typically about 8 L / min, preferably 7.8 L / min, or 1.5-3.5 L / min, typically 2-3 L / min, or greater than 40 L, typically 50 L.

[0029] In use, a fluid flow conditioner can be provided with a strainer at the fluid inlet so that it can continue to function properly even when particles are present in the fluid flow. The strainer has openings and / or holes that are smaller than the openings and / or flow-through openings located in the fluid flow conditioner downstream of the strainer. As such, particles, such as solids, that can pass through the strainer will generally flow through the fluid flow conditioner and exit at the fluid outlet. Larger particles are not permitted to pass through the strainer into the fluid flow conditioner.

[0030] The concave and / or convex shape of the valve member may also be referred to as its convexity. The convexity of the valve member may be described as the curved shape and / or curvature of the valve member.

[0031] The valve member may have a curved shape such that the vertical distance between a line parallel to the lowermost surface of the convex side of the valve member and the uppermost edge of the concave side of the valve member is preferably 0.005 to 0.1 mm greater than the average thickness of the valve member, and preferably 0.01 to 0.03 mm greater. This distance is 0.015 to 0.025 mm greater than the average thickness of the valve member, and typically 0.02 mm greater. The average thickness of the valve member may be referred to as the nominal thickness of the valve member. The valve member may have a curvature with a radius of 800 to 1200 mm, preferably 900 to 1100 mm, and most preferably approximately 1000 mm.

[0032] This results in a fluid flow regulator with a fluid delivery of 4 to 10 L / min, particularly 7.5 to 8.5 L / min, typically about 8 L / min, and preferably 7.8 L / min. For fluid flow regulators according to the invention designed for fluid delivery at flow rates other than 7.8 L / min, the vertical spacing may vary, but will be substantially proportional to the difference in required flow rate.

[0033] This spacing generally does not include any burrs or lips on the convex edge of the valve member, typically the upper edge.

[0034] The lowermost surface or point of the valve member is generally midway between the outermost surface of the valve member tab and the opposite outermost edge of the valve member.

[0035] The thickness of the valve member may be 0.1mm to 2.5mm, typically 0.2 to 1.5mm, more typically 0.25 to 0.5mm, usually 0.35 to 0.4mm, 0.392mm, all of which may be ±0.02mm.

[0036] The present inventors have realized that while batches of material used to make valve members generally vary in thickness within known tolerances, this variation in thickness generally causes significant variations in the fluid flow rate from a fluid flow regulator during use. The present inventors have developed a fluid flow regulator that can be reliably and reproducibly manufactured and that, in use, provides a reliably and reproducibly fluid flow rate. The concave shape of the valve member mitigates the effects of the aforementioned variations in the thickness of the valve member material.

[0037] The concave and / or convex shape of the valve member, also referred to as its convexity, can be altered to change the flow rate of fluid through and / or out of the fluid flow regulator. If the valve member were flat, the thickness of the material of the valve member would generally have to be changed each time the flow rate or flow velocity is changed. Instead, the concave and / or convex shape of the valve member, also referred to as its convexity, can be changed to change the flow rate of fluid through and / or out of the fluid flow regulator. By varying the shape of the convexity, the flow rate or flow velocity of the fluid flow regulator can be more easily varied as needed.

[0038] The valve chamber is typically made of plastic and may be made of glass-filled polymer and / or glass-filled plastic. The valve member is typically made of stainless steel, preferably spring steel.

[0039] According to a further embodiment, the lowermost surface of the valve member has an asymmetric height distribution, which reduces any vibration in the fluid flow regulator. As a fluid flow regulator, in particular its valve seat, preferably has a symmetric shape for gradually receiving or contacting the valve member. The asymmetric shape of the lowermost surface of the valve member results in gradual contact of the parts, thereby reducing vibration.

[0040] Preferably, a first edge of the valve member is positioned out of the plane of a second edge of the valve member opposite the first edge of the valve member, such that both edges of the valve member preferably contact the valve seat. The asymmetric or varying lowermost surfaces of the edges reduce any vibration.

[0041] Preferably, the lowermost surface of the valve member contacts the valve seat at two opposing edges. As pressure or fluid flow increases, a large portion of the valve member bends and moves progressively toward the valve seat, thereby reducing the flow opening between the valve member and the valve seat. Because the valve seat, and at least the portion that cooperates with the valve member, such as the protruding member described above, are symmetrical, the asymmetrical shape of the opposing edges has the effect of providing a constant pressure or flow. Only the first edge contacts the valve seat, and the opposing edge contacts the valve member only as pressure increases further.

[0042] Preferably, the valve member includes a tab or other member for positioning the valve member within the valve chamber. The tab is positionable by a portion of the valve chamber, and when viewed in a cross section perpendicular to a line between the outermost surface of the tab and the opposite outermost edge of the valve member, the lowermost surface of the valve member has an asymmetrical shape such that the edges on either side of the line connecting the tab and the opposite edge extend to different positions when viewed perpendicular to the plane of the valve member, at least in the rest position.

[0043] According to a further preferred embodiment, the valve member is movable relative to a valve seat defining a flow opening therebetween. At least in a rest position, a distance between a first edge of the valve member and the valve seat is different from a distance between a second edge of the valve member opposite the first edge and the valve seat. When pressure or flow increases, the first edge contacts the valve seat first, and the second edge contacts only when pressure or flow increases. The opposite edges are defined as being on either side of a line of substantial mirror symmetry of the respective valve seat, preferably directly opposite each other.

[0044] Preferably, the valve seat is provided with at least one first protruding member for engaging a first edge of the valve member and at least one second protruding member located opposite the first protruding member for engaging a second edge of the valve member, such that the spacing between the valve member and the first and second protruding members is different. Preferably, the spacing between the first edge of the valve member and the first protruding member is different from the spacing between the second edge and the opposite second protruding member. The first and second protruding members have substantially the same height relative to the valve seat, in other words, extend from the valve seat at substantially the same height.

[0045] Preferably, the difference in height between the first edge and the second edge opposite the first edge of the lowermost surface of the valve member is 0.005 to 0.1 mm, preferably 0.01 to 0.03 mm, more preferably approximately 0.02 mm.

[0046] It should be noted that although the combination of the asymmetric underside of the valve member and the concave shape provides a more reliable valve member, e.g., due to reduced vibration of the valve member, it may be possible to provide an asymmetric valve member as described above without the valve member being concave.

[0047] The fluid flow regulator may further comprise a check valve. It may be an advantage of the present invention that the check valve reduces the likelihood that fluid flow will induce Legionnaires' disease during use. The check valve may include one or more seals. The material of these seals may be selected to reduce the risk that the one or more seals will harbor Legionnaires' disease.

[0048] The fluid flow regulator typically further comprises a resistance controller downstream of the valve member. The resistance controller may be referred to as a fluid flow control mechanism. The resistance controller is typically at a fluid outlet of the fluid flow regulator. The resistance controller is typically used to control the fluid pressure in a portion of the valve chamber downstream of the valve member, and in particular allows for adjustment of the pressure drop across the valve member. In use, the resistance controller typically restricts fluid flow from the valve chamber, thereby helping to control backpressure acting downstream of the valve member. In doing so, the fluid flow regulator helps to provide at least substantially pressure-independent fluid flow. A substantially pressure-independent fluid flow may be a pressure-independent fluid flow.

[0049] During use, fluid enters the valve chamber and depresses the valve member, preferably toward the valve seat. The fluid passes through the valve member and the valve seat and flows through a gap or through-flow opening between the valve member and the valve seat. The valve seat preferably has an inclined upper surface, such that a first component of the tangent of the upper surface is substantially opposite to the general direction of fluid flow, and a second component of the tangent of the upper surface is radially directed toward the longitudinal axis of the valve chamber. Fluid flow passing between the valve member and the valve seat thereby generates a force on the downstream side of the valve member that includes a component substantially opposite to the general direction of fluid flow (i.e., from the inlet to the outlet), such that the valve member is preferably at least partially supported by the fluid flow passing through the valve member. The greater the pressure on the entire upstream side of the valve member, and therefore the fluid force, the further the valve member moves toward the valve seat. This reduces the through-flow opening between the valve member and the valve seat, and the substantially constant through-flow of fluid through this smaller opening increases the velocity of the fluid passing through the through-flow opening. Thus, an increase in fluid velocity results in an increased force acting on the downstream side of the valve member, providing greater support for the entire downstream side of the valve member. This allows the flow itself to have a balancing effect on the valve member, resulting in a substantially constant fluid flow over a relatively wide range of fluid pressures provided to the inlet. Additionally, in combination with a resistance controller (or fluid flow regulator) positionable at the outlet, the limited fluid flow through the fluid flow regulator downstream of the valve member limits the pressure drop over the valve member, so that the valve member is also supported by the back pressure of the fluid downstream of the valve member.

[0050] Advantages of the present invention may include the ability of the fluid flow regulator to operate in this manner over a wide range of fluid flow rates and / or fluid pressures while the fluid flow exiting the fluid flow regulator remains at a substantially constant flow rate and / or volume, and the fluid flow exiting the fluid flow meter may be at a constant flow rate and / or volume.

[0051] An advantage of the present invention may be that, in use, the fluid exiting the fluid flow regulator remains at a substantially constant flow rate and / or volume when the flow rate and / or pressure of the fluid entering the fluid flow regulator is low, high, increasing, or decreasing. The fluid exiting the fluid flow regulator is generally at a constant flow rate and / or volume.

[0052] According to a further aspect, there is provided a method for manufacturing the fluid flow regulator described above, the method comprising: providing a valve member; forming the valve member to have a concave shape and / or a lowermost surface of the valve member to have an asymmetric height distribution; providing a valve chamber for the fluid flow regulator; combining the valve member and the valve chamber to form the fluid flow regulator.

[0053] By adjusting the concave shape and / or bottom surface for symmetry, a reliable fluid flow regulator as described above is provided. Shaping the valve member may include, for example, stamping the valve member between correspondingly shaped forming members. The forming members may define a concave and / or asymmetric chamber therebetween to form the valve member.

[0054] In a preferred embodiment of the method for producing, the method comprises: determining a stiffness parameter of the valve member; and designing the concave shape of the valve member and / or the shape for the asymmetric height distribution of the lowermost surface of the valve member based on the determined stiffness parameters before shaping the valve member.

[0055] By basing the geometry for the concave shape and / or asymmetric height distribution of the valve member on the determined stiffness parameters of the valve member or the raw material from which the valve member is formed, the manufacturing process can be adapted to the changing characteristics of the supplied raw material. Obtaining, for example, steel, particularly suitable spring steel, at an exact predefined thickness can result in significant additional costs to the manufacturing process or additional waste due to improperly produced material batches. By designing the geometry for the concave shape and / or asymmetric height distribution of the valve member depending on the actual determined (e.g., measured) thickness of a batch of steel plate / strip, valve members and therefore fluid flow regulators with substantially equal performance can be obtained from different batches of steel strip with varying thicknesses. This can reduce waste and / or costs in the manufacturing process.

[0056] The method may further include determining stiffness parameters of the shaped valve member, comparing the stiffness parameters to predefined target stiffness parameters, and adapting the design of the valve member based on the comparison, which allows adapting the valve member to the target stiffness in an iterative process.

[0057] Alternatively or additionally, a preferred embodiment of the method comprises: determining a stiffness parameter of the valve member; and adapting the size, shape and / or position of the valve seat based on the determined stiffness parameters, which determines the geometry, such as width and length, of the through-flow opening between the valve member and the valve seat.

[0058] Thus, instead of or in addition to designing and / or modifying the specific shape of the valve member as described above, the stiffness and / or bending characteristics of the valve member can be compensated for by adapting the shape and / or position of the valve seat, again reducing waste and / or costs in the manufacturing process and resulting in a more adaptable manufacturing process.

[0059] Preferably, the step of adapting the size, shape, and / or position of the valve seat includes adapting the size, shape, and / or position of at least one protrusion disposed on the valve seat that limits movement of the valve member toward the valve seat. The protrusion disposed on the valve seat is relatively easily adaptable to a mold for forming the valve chamber so that the flow characteristics of the flow regulator can be easily adapted to desired specifications based on the determined stiffness parameters.

[0060] Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: [Brief explanation of the drawings]

[0061] [Figure 1] FIG. 1 is a cross-sectional view of a fluid flow regulator. [Figure 2] FIG. 2 is a plan view of the valve member. [Figure 3] FIG. 3 is a cross-sectional view of the valve member. [Figure 4] FIG. 4 is a cross-sectional view of the fluid flow regulator taken along line IV of FIG.

[0062] FIG. 1 shows a cross-sectional view of a fluid flow regulator 10. The fluid flow regulator 10 includes a valve chamber 12 having a fluid inlet 14a and a fluid outlet 14b. Within the valve chamber 12 is a valve member 16. The valve member 16 is movable within the valve chamber 12 and is capable of contacting a valve seat 18 within the valve chamber 12. Importantly, the valve member 16 has a concave shape. FIG. 1 does not show the fluid within the fluid flow regulator 10.

[0063] Fluid flow regulator 10 may also be referred to as a dynamic fluid flow regulator because valve member 16 is movable relative to valve chamber 12. This is in contrast to commonly available fluid flow regulators that rely on pressure drop.

[0064] 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 check valve 22 and a resistance controller 29 at the bottom or fluid outlet 14b of the fluid flow regulator. The check valve 22 may also be referred to as a check valve. The strainer 20 has a pin 21 that helps keep the valve member 16 within the valve chamber 12.

[0065] The strainer 20 at the top or fluid inlet 14a of the fluid flow regulator 10 helps prevent larger solid particles from entering the valve chamber 12. Because 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, solid particles do not accumulate within the fluid flow regulator 10. Therefore, solid particles that enter the fluid flow regulator 10 generally escape.

[0066] The valve member 16 is concave in the direction of the fluid inlet 14a and convex in the direction of the fluid outlet 14b.

[0067] In use, the valve member 16 is movable within the valve chamber 12 and is capable of contacting a valve seat 18 within the valve chamber. The valve member 16 is movable relative to the valve seat 18. The valve seat 18 preferably has a radial width 19 of 1.97 mm.

[0068] In use, the resistance controller 29 is used to control or manipulate the back pressure of the fluid (not shown) in the valve chamber. The resistance controller 29 restricts the flow of fluid from the valve chamber 12 to create a higher back pressure.

[0069] During 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 and through the gap 26 between the valve member 16 and valve seat 18. Due to restricted fluid flow downstream of the valve member 16 through the fluid flow regulator 10, for example, caused by the resistance controller 29, some of the fluid (not shown) that flows past the valve member 16 and valve seat 18 pushes back on the valve member 16, against the general direction of fluid flow indicated by arrow 30. This is due to the shape of the valve seat. The greater the fluid force and pressure on the upstream side of the valve member 16, the greater the support of the fluid from the downstream side of the valve member. If the fluid force and pressure on the upstream side of the valve member 16 decreases, the support of the fluid from the downstream side of the valve member also decreases.

[0070] Arrow 30 indicates the general direction of fluid flow and the longitudinal axis of valve chamber 12 .

[0071] The valve member 16 has a tab 28 (see also FIG. 2 ) that is used to position the valve member within the chamber 12. The valve member 16 also has an opening 32 therein for positioning the valve member within the valve chamber 12. The valve chamber 12 has a post 34, and the opening 32 in the valve member 16 is positioned relative to the post 34. That is, when the valve member 16 is within the valve chamber 12, the post 34 can pass through the opening 32.

[0072] FIG. 2 is a plan view of a valve member 16 of a fluid flow regulator according to the present invention, preferably a 7.8 L / min version. The 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 side of the valve member 16, which faces the inlet (i.e., toward and / or adjacent to the fluid inlet). The convex side of the valve member 16, which faces the outlet (i.e., toward and / or adjacent to the fluid outlet), is not shown. The lowermost surface or lowest point of the valve member 16 is at midpoint 16d on line A between the outermost side of the valve member tab and the opposite outermost edge 16h of the valve member 16.

[0073] Figure 3 is a cross-sectional view of the valve member 16 of a fluid flow regulator according to the present invention, preferably a 7.8 L / min version, taken along line A in Figure 2. The average thickness of the valve member is preferably 0.392 mm ± 0.02 mm. The valve member 16 is curved such that the vertical distance 16e from a line parallel to the lowermost surface 16c of the convex side of the valve member facing the outlet and the uppermost edge 16b of the concave side of the valve member facing the inlet is preferably 0.39 mm, which is preferably 0.02 mm greater than the average thickness of the valve member, which is preferably 0.37 mm.

[0074] FIG. 4 shows a cross-sectional view along arrow IV in FIG. 1. In this view, it can be seen that the lowermost surface of the valve member 16 is asymmetrically shaped when viewed in a plane perpendicular to line A (between tab 28 and opposite edge 16h) in FIG. 3. Here, line A can be seen as a line of substantial mirror image of the respective valve seats. That is, the lowermost surface at first edge 16f (see also FIG. 2) is positioned out of plane with the lowermost surface at second edge 16g. Edge 16g is positioned lower than edge 16f. The distance d2 between the lowermost surface of the valve member 16 at edge 16g and the valve seat 18 is smaller than the distance d1 between the lowermost surface of the valve member 16 at edge 16f and the valve seat 18. The difference between distances d1 and d2 is preferably 0.03 mm in this example.

[0075] It can also be seen that the valve seat 18 is provided with protrusions 18a that protrude from the surface of the valve seat 18. The protrusions 18a limit the movement of the valve member 16 toward the valve seat 18, ensuring that a flow opening 26 remains between the valve member 16 and the valve seat 18. The protrusions 18a extend in the same cross section as shown in Figure 4. Multiple sets of protrusions may be arranged, each set extending in a plane parallel to the plane shown in Figure 4, i.e., a plane substantially perpendicular to line A in Figure 2.

[0076] In use, when the valve member 16 flexes due to increased fluid pressure, the opposite edge 16h (see FIG. 2) has the longest travel length, and edges 16f and 16g contact the symmetrically disposed projections 18a of the valve seat 18 with different pressures due to the asymmetrical lowermost surface (relative to line A) of the valve member 16. This reduces the occurrence of vibrations that might otherwise occur if the valve member 16 contacted projections 18a with substantially equal pressures.

[0077] Changes and modifications may be incorporated herein without departing from the scope of the present invention.

Claims

1. a valve chamber having a fluid inlet and a fluid outlet; a valve member within the valve chamber, the valve member being movable within the valve chamber relative to a valve seat and defining a flow opening therebetween; a spacing between a first edge of the valve member and the valve seat that is different from a spacing between a second edge of the valve member opposite the first edge and the valve seat, at least in a rest position; The fluid flow regulator wherein the first and second edges are defined on opposite sides of a line of substantial mirror symmetry of the respective valve seats.

2. The fluid flow regulator of claim 1 , wherein the lower surface of the valve member has an asymmetric height distribution.

3. 3. The fluid flow regulator of claim 1 or 2, wherein a first edge of the valve member is positioned vertically offset from a second edge of the valve member opposite the first edge.

4. 4. The fluid flow regulator of claim 1, 2 or 3, wherein the valve member includes a tab for positioning the valve member within the valve chamber, the tab being positionable by a portion of the valve chamber.

5. 5. The fluid flow regulator of claim 4, wherein, when viewed in a cross section perpendicular to a line between the outermost surface of the tab and the opposite outermost edge of the valve member, the lowest point of the lower surface of the valve member has an asymmetrical shape, at least in the rest position.

6. 6. The fluid flow regulator of claim 4, wherein, when viewed in a cross section perpendicular to a line between an outermost surface of the tab and an opposite outermost edge of the valve member, at least in a rest position, a distance between a first edge of the valve member and the valve seat is different from a distance between a second edge of the valve member opposite the first edge and the valve seat.

7. 7. A fluid flow regulator according to claim 1, wherein the difference in height of the lower surface of the valve member between a first edge and a second edge opposite the first edge is 0.005 to 0.1 mm.

8. A fluid flow regulator according to any preceding claim, wherein the valve member is deformable such that the shape of the valve member can change during use.

9. A fluid flow regulator according to any preceding claim, wherein the valve member is concave.

10. 10. The fluid flow regulator of claim 9, wherein the valve member is concave in a rest position when the fluid flow regulator is not in use.

11. 10. The fluid flow regulator of claim 9, wherein the valve member is concavely shaped so that the valve member is not flat prior to placing the valve member within the valve chamber.

12. 12. The fluid flow regulator of claim 9, 10 or 11, wherein the valve member is dish-shaped.

13. A fluid flow regulator according to any one of claims 9 to 12, wherein the valve member is concave in the direction of the fluid inlet and convex in the direction of the fluid outlet.

14. 14. The fluid flow regulator according to claim 9, wherein the valve member is concave such that the vertical distance between a horizontal plane including the lowest point of the lower surface of the convex side of the valve member and a horizontal plane including the highest point of the concave side of the valve member is 0.005 to 0.1 mm larger than the average thickness of the valve member.

15. A fluid flow regulator according to any preceding claim, wherein the valve member has an average thickness of 0.1 to 2.5 mm.

16. A method for manufacturing a fluid flow regulator according to any one of claims 1 to 15, comprising the steps of: providing a valve member; forming the valve member to have a concave shape and / or a lower surface of the valve member to have an asymmetric height distribution; providing a valve chamber for the fluid flow regulator; combining the valve member and the valve chamber to form the fluid flow regulator.

Images