Valve diaphragm

Abstract

The invention relates to: A valve diaphragm (100) with a functional region (130), which is surrounded by an outer clamping region (120), wherein a wet-side surface (124), which spans the functional region (130) and the clamping region (120), is provided at least in some portions with at least one, in particular regular, microstructure (150).

Description

[0001] Title: Valve membrane

[0002] Description

[0003] The invention relates to a valve membrane.

[0004] Valve diaphragms for use in diaphragm valves are well known.

[0005] The problems of the prior art are solved by a valve membrane according to claim 1.

[0006] One aspect of the description relates to a valve membrane having a functional region which is surrounded by an outer clamping region, wherein a wet-side surface which spans the functional region and the clamping region is provided at least in sections with at least one particularly regular microstructure.

[0007] Providing the surface with a regular microstructure prevents microcracks by improving the mobility and stability of the wet-side surface. This extends the service life of the valve diaphragm. Furthermore, maintenance intervals can be extended and cleanability benefits.

[0008] Furthermore, the microstructure can improve the hydrophobic properties of the wet-side surface.

[0009] For example, it is advantageous that at least one microstructure covers the clamping area and the functional area of ​​the wet-side surface.

[0010] This example is particularly advantageous in conjunction with the raised, connected micro-webs, for example the honeycomb-shaped microstructure, since, in particular, connected, raised webs are accompanied by a stabilizing effect and an increased sealing effect in conjunction with a counter-sealing section.

[0011] Advantages are achieved in that the at least one microstructure is honeycomb-shaped or net-like.

[0012] The stability of the surface is advantageously improved. For example, it is advantageous if the at least one microstructure comprises connected raised microribs that surround microrecesses.

[0013] This advantageously creates a common raised surface that is not interrupted by micro-depressions, but rather acts as a continuous micro-barrier. Particularly in the clamping area and the sealing web area, differences in the sealing partner, such as scratches, can be compensated for by the microstructure and micro-material flow.

[0014] For example, it is advantageous that an average maximum distance between two opposing micro-webs of the associated micro-recess of the microstructure is between 10 pm and 500 pm, in particular between 10 and 100 pm.

[0015] It is advantageous, for example, that the at least one microstructure comprises a continuous, recessed micro-surface which surrounds micro-elevations.

[0016] It is advantageous that the functional area of ​​the wet-side surface with a first microstructure has a first contact angle, and wherein the clamping area with a second microstructure has a second contact angle which is smaller than the first contact angle. The functional area is therefore more hydrophobic than the clamping section. The process medium provided by the membrane therefore adheres less strongly to the functional area. On the other hand, the smaller second contact angle has a beneficial effect on the clamping of the membrane between the wet-side surface of the clamping section and the counter-sealing section of the valve body and thus has a beneficial effect on the outward tightness.

[0017] It is advantageous that the micro-recesses or the at least one recessed micro-surface are or are convex at least in sections.

[0018] This not only improves mobility but also reduces flow resistance.

[0019] It is advantageous that a flexion region of the wet-side surface is arranged between the clamping region and a central region through which the adjusting axis runs, and wherein the flexion region comprises the at least one microstructure.

[0020] The dynamically stressed milling area thus benefits from the microstructure, which prevents cracks, especially microcracks.

[0021] For example, it is advantageous that at least some of the raised micro-webs in a clamping area of ​​the wet-side surface follow a contour of the clamping area, in particular a circular shape.

[0022] This advantageously creates a barrier to provide a defined sealing edge when clamping the sealing area or clamping area. Furthermore, entrainment of the process fluid into the sealing area is reduced.

[0023] Unevenness on the surface of a mating section of the valve body assigned to the clamping section can be advantageously compensated for as soon as the clamping section is pressed onto the mating section with the clamping force. In particular under the clamping force, the structures on the wet-side surface of the clamping section can flow and thus increase the outward tightness. Assembly is improved because, despite an enlarged assembly process window, e.g. an enlarged torque window, the outward tightness can be reliably established. This means that the sealing force introduced into the clamping area can remain the same or even be reduced, whereby the width of the clamping section can be reduced at the same time. This improves the outward tightness of the diaphragm valve, increases the service life of the diaphragm and saves installation space.

[0024] It is advantageous, for example, that at least some of the raised micro-webs in a sealing web region of the wet-side surface running through a feed axis follow a longitudinal contour of the sealing web region.

[0025] These micro-elevations advantageously improve the sealing effect in the web area, i.e. the sealing effect towards the inside.

[0026] For example, it is advantageous that a rise of at least one number of the raised micro-webs facing the adjustment axis is steeper than an associated rise facing away from the adjustment axis.

[0027] The barrier effect of the micro-bridges is advantageously improved.

[0028] For example , it is advantageous that a ratio of the mean distance between adjacent micro - elevations and a mean depth of the microstructure is between 0 .2 and 0 .9 , in particular between 0 .2 and 0 .6 .

[0029] This can advantageously increase the sealing effect and also improve the hydrophobic behavior of the surface.

[0030] For example, it is advantageous for a rise of at least one number of the micro-webs facing the central longitudinal axis of the sealing web region to be steeper than a corresponding rise facing away from the central longitudinal axis. This advantageously improves the barrier effect of the micro-webs.

[0031] For example, it is advantageous that the micro-elevations increase the contact angle of the wet-side surface.

[0032] The freestanding micro-elevations, in particular, advantageously increase the contact angle. This increased contact angle ensures better cleanability. Since even PFTE or PFA are subject to aging processes, the freestanding micro-elevations ensure that the desired contact angle can be maintained over longer periods. The service life and service life of the valve diaphragm is increased. Cleaning-related costs can be reduced. The media-wetted surface of the functional area particularly benefits from this microstructure.

[0033] For example, it is advantageous that concentric subregions of the flexion region of the wet-side surface, in particular an intermediate region and edge regions of the flexion region surrounding the intermediate region, have at least two microstructures that are different from one another.

[0034] Tensile forces acting concentrically on the intermediate area act on the intermediate area. The edge areas surrounding the intermediate area, however, are subject to rolling motion. Accordingly, differently designed microstructures support the respective movement or reinforce the respective wet-side surface. The drawing shows:

[0035] Figure 1 shows a 2-part valve membrane in a perspective view;

[0036] Figure 2 is a schematic view of a wet-side surface of a valve membrane with a similar microstructure;

[0037] Figure 3 schematic examples of microstructures in a span area of ​​the membrane;

[0038] Figure 4 is a schematic sectional view of the examples of microstructures from Figure 3;

[0039] Figure 5 schematic examples of microstructures in a sealing web area of ​​the wet-side surface of the membrane;

[0040] Figure 6 is a schematic sectional view of the examples of microstructures from Figure 5;

[0041] Figure 7 schematic examples of microstructures in a flexed area of ​​the valve membrane; and

[0042] Figure 8 shows a schematic view of the wet-side surface of an example of the valve diaphragm with various microstructures in the flexion region. Figure 1 shows a perspective view of an exemplary two-part diaphragm 300 comprising a first diaphragm 100 facing a valve body of a diaphragm valve and a second diaphragm 200 facing a drive of the diaphragm valve. The second diaphragm 200 is made, for example, from an elastomer, and the first diaphragm 100 is made from a highly chemically resistant plastic material such as PFA or PTFE. Through-openings 110-116 lead through both valve diaphragms 100 and 200 and serve to pass through fastening means such as stud bolts.

[0043] Figure 1 is merely an example. Other embodiments are of course also conceivable, in particular, membranes 100 with a substantially round outer contour and / or without the through-openings 110-116. In particular, one-piece implementations are also conceivable, for example, having only the first membrane 100. In particular, the one-piece membrane 100 can also be made of a different material, such as an elastomer material such as EPDM.

[0044] The figure relates to the valve diaphragm 100 with a functional region 130, which is surrounded by an outer clamping region 120, wherein a wet-side surface 124, which spans the functional region 130 and the clamping region 120, is provided at least in sections with at least one, in particular regular, microstructure 150. The two-part diaphragm 300 is clamped or clamped in the lateral clamping region 120 between the valve body and the drive. The diaphragm 100 is clamped in the clamping region 120 between two components of the diaphragm valve and seals the diaphragm valve to the outside.

[0045] The functional area 130 of the valve membrane 100 is pressed onto the valve seat of the valve body in order to close the fluid channel for process fluid formed by the valve body and a wet side 122 of the first membrane 100.

[0046] The valve membrane 100 comprises the wet-side surface 124 visible in Figure 1 and a dry-side surface facing the actuator. The wet-side surface 124 spans the functional area 130 and the clamping area 120. The movement is caused by an actuator rod moved by the actuator along an actuating axis S, which presses, for example, with a pressure piece onto the two-part membrane 300. In this case, a sealing ridge 132 of the first membrane 100, indicated in the figure, presses onto the valve seat. Of course, the sealing ridge can be designed as a visible elevation in other

[0047] The fluid channel is opened by moving the first diaphragm 100 away from the valve seat.

[0048] The actuating axis S runs, for example, perpendicular to an imaginary diaphragm plane in the region of an imaginary center point of the valve diaphragm 100. The diaphragm 100 comprises a static, central region 134 in the functional region 130, which, on the wet side, is pressed onto the valve seat by the lateral sections of the sealing land region to close the diaphragm valve. In addition to the aforementioned pressure loads, the central region 134 is moved essentially along the actuating axis S.

[0049] The diaphragm 100 comprises a dynamic region 136, also referred to as the flexion region, which surrounds the central region 134. The dynamic region 136 ensures, through a movement, that the central region 134 can be lifted from the valve seat, opening a cross-section for the flow of the process fluid. The movement of the dynamic region 136 corresponds to a concentric flexion movement. The diaphragm 100 comprises the static clamping region 120, which surrounds the dynamic region 136.

[0050] A schematically enlarged section A1 shows the microstructure 150 present on the wet-side surface 124, which in the present case has raised elevations following a lattice or net shape.

[0051] Microstructures can also be arranged on the dry side of the membrane 100, for example to prevent material wear.

[0052] The regularity of the microstructure 150 includes, for example, a repetition of a microstructure pattern across a portion of the surface 124. In another example, the regularity of the microstructure 150 means that the elevations and / or recesses are incorporated into the surface according to a geometric design rule. The regularity of the microstructure 150 can thus be recognized by a micro-inspection of the wet-side surface 124.

[0053] To produce the microstructures 150, for example, the manufacturing tool is pre-contoured accordingly.

[0054] Figure 2 shows the membrane 100 in a schematic view of its wet-side surface 124. The through-openings 110-116 are not shown for clarity.

[0055] It is shown that the at least one microstructure 150 covers the clamping region 120 and the functional region 130 of the wet-side surface 124. The at least one microstructure 150 is honeycomb-shaped and / or reticulated.

[0056] The honeycomb-shaped microstructure 150 covers the clamping region 120, the flexion region 136, and the sealing web 132, as shown in the schematic enlarged sections A2a, A2b, A2c. In particular, the entire wet-side surface 124 can be covered with the microstructure 150.

[0057] It is depicted that the at least one microstructure 150 comprises contiguous raised microribs 152 that hexagonally surround microrecesses 154. A mean maximum distance dMax between two opposing microribs 152 of the associated microrecess 154 of the microstructure 150 is between 10 pm and 500 pm, in particular between 10 and 100 pm.

[0058] The distance dMax represents the maximum distance for an arrangement of directly opposite micro-bridges 152. Across several micro-bridge pairs, the respective distance is averaged to the distance dMax.

[0059] Figure 3 shows, in schematically enlarged sections A3a, A3b, A3c, various forms of the clamping region 120 of the wet-side surface 124. The clamping region 120 surrounds the functional region 130 and thus has a circular inner edge. Depending on the form of the valve membrane 100, the clamping region 120 is raised in a circular ring on the wet side. The contour of the clamping region 120 is therefore circular. The sections A3a-c show the different examples of the microstructure 150 in the clamping region 120, wherein a respective radially extending axis Ra-c is shown.

[0060] The examples show that at least some of the raised micro-webs 152 in a clamping region 120 of the wet-side surface 124 follow a contour of the clamping region 120, in particular a circular shape. In particular, the micro-webs 152 run uninterrupted along the contour of the clamping region 120. According to section A3a, the raised micro-webs 152, with a micro-recess 154 arranged between them, run in a groove-like manner and concentrically to the adjusting axis S. According to section A3b, raised micro-webs 152x each run perpendicular to the radially extending axis Rb. According to section A3c, raised micro-webs 152 run in a wave-like manner in the circumferential direction, i.e., along the circular contour of the sealing region 120.

[0061] Figure 4 schematically shows a section of the clamping region 120 of the valve membrane 100, with the adjustment axis S lying in the continuation of the section. The wet-side surface 124 comprises the microstructure 150 shown in the section.

[0062] A ratio of the average distance dMax between adjacent micro-elevations 164 and an average depth t of the microstructure 150 is between 0.2 and 0.9, in particular between 0.2 and 0.6. This can also be applied to the other microstructures 150 shown.

[0063] It is shown that a rise 156 facing the adjustment axis S of at least a number of the raised micro-webs 152 is steeper than an associated rise 158 facing away from the adjustment axis S.

[0064] Figure 5 shows, in schematically enlarged sections A5a, A5b, A5c, various configurations of the sealing ridge region 132 of the wet-side surface 124. It is shown that at least some of the raised micro-ridges 152 in a sealing ridge region 132 of the wet-side surface 124 extending through a feed axis S follow a longitudinal contour of the sealing ridge region 132.

[0065] The sealing ridge region 132 is arranged within the functional region 130 and extends along a central longitudinal axis M. Depending on the configuration of the valve membrane 100, the sealing ridge region 132 is either raised or not raised in a ridge-like manner on the wet side. The contour of the sealing ridge region 132 is elongated. The sections A3a-c show the different examples of the microstructure 150 in the sealing ridge region 132, with a respective central longitudinal axis M being displayed.

[0066] According to section A5a, the raised micro-webs 152, each with a micro-recess 154 arranged therebetween, run in a groove-like manner and parallel to the central longitudinal axis M . According to section A5b, connected raised micro-webs 152 of the honeycomb structure follow a respective parallel axis of the central longitudinal axis M . According to section A5c, raised micro-webs 152 run in a wave-like manner and follow a parallel axis of the central longitudinal axis M .

[0067] Figure 6 schematically shows a section of the sealing web region 132 of the valve membrane 100, wherein the section includes the actuating axis S in an extension. The wet-side surface 124 includes the microstructure 150 shown in the section.

[0068] For example, it is shown that a rise 156 facing the central longitudinal axis M of the sealing web region 132 of at least a number of the micro-webs 152 is steeper than an associated rise 158 facing away from the central longitudinal axis M.

[0069] Figure 7 shows, in schematically enlarged sections A7a-e, various forms of the dynamic region 136 of the wet-side surface 124, which can also be referred to as a dynamically loaded region or flexed section. Sections A7a-e each show individual microstructures 150 that cover the dynamic region 136 at least in sections.

[0070] For example, in the enlargements A7a-c it is shown that the at least one microstructure 150 comprises a continuous recessed micro-surface 162 which surrounds micro-elevations 164.

[0071] The micro-elevations 164 increase the contact angle of the wet-side surface 124 compared to a flat formation of the respective surface and in comparison to a contact angle mainly determined by the material.

[0072] In particular, the functional region 130 of the wet-side surface 124 has a first microstructure 150 with a first contact angle, wherein the clamping region 120 with a second microstructure 150 has a second contact angle which is smaller than the first contact angle. In particular, the second contact angle is at least 20°, in particular at least 40°, in particular at least 60° smaller than the first contact angle. The contact angle relates to the interaction of the respective surface with water.

[0073] According to section A7a, dome-shaped micro-elevations 164 rise from the continuous micro-surface 162. According to section A7b, continuous, recessed micro-webs in the form of a continuous micro-surface 162 follow a honeycomb structure. Micro-elevations 164 rise from the micro-surface 162 and are separated from one another by the micro-surface 162. According to section A7c, tetrahedral micro-elevations 164 extend from recessed micro-depressions, which are collectively referred to as the micro-surface 162.

[0074] The micro-recesses 154 are or the at least one recessed micro-surface 162 is at least partially convex.

[0075] In contrast to sections A7a and A7b, sections A7d and A7e essentially show an inverted pattern of microstructures 150. Thus, in the schematically illustrated section A7d, a continuous surface in the form of raised micro-ribs 152 is present, into which convex or dome-like micro-recesses 154 are introduced. The schematically illustrated section A7e shows a honeycomb-shaped microstructure 150, in which interconnected micro-ribs 152 form the honeycomb shape and are introduced between the micro-ribs.

[0076] Figure 8 shows, in contrast to Figure 7, that the wet-side surface 124 in the dynamic region 136 is provided with different microstructures 150, at least outside the sealing web region 132.

[0077] For example, it is shown that the flexion region 136 of the wet-side surface 124 is arranged between the clamping region 120 and the central region 134 through which the adjustment axis S runs, wherein the flexion region 136 comprises the at least one microstructure 150.

[0078] It is shown that concentric subregions 180, 182, 184 of the flexed region 136 of the wet-side surface 124, in particular an intermediate region 182 and edge regions 180, 184 of the flexed region 136 surrounding the intermediate region 182, have at least two microstructures 150 that are different from one another.

[0079] For example, the intermediate region 182 comprises a microstructure 150 that primarily reinforces the surface, such as a honeycomb shape, and the edge regions 180, 184 comprise microstructures 150 that primarily have a hydrophobic effect or support the flexion movement. The schematically illustrated enlarged section A8a shows the microstructure 150 in the edge regions 180 and 184, each with concave depressions surrounded by rounded edges, which are surrounded by the raised webs 152. The section A8b, on the other hand, shows a honeycomb-shaped microstructure 150 for the intermediate region 182 or the wet-side surface 124 of the intermediate region 182.

Claims

Patent claims 1. A valve diaphragm (100) with a functional area (130) which is surrounded by an outer clamping area (120), wherein a wet-side surface (124) which spans the functional area (130) and the clamping area (120) is provided at least sectionally with at least one, in particular regular, microstructure (150).

2. The valve diaphragm (100) according to claim 1, wherein the at least one microstructure (150) covers the clamping area (120) and the functional area (130) of the wet-side surface (124).

3. The valve diaphragm (100) according to claim 1 or 2, wherein the at least one microstructure (150) is honeycomb-shaped or net-like.

4. The valve diaphragm (100) according to any one of claims 1 to 3, wherein the at least one microstructure (150) comprises connected raised micro-ridges (152) which surround micro-recesses (154).

5. The valve diaphragm (100) according to claim 4, wherein at least a part of the raised micro-ridges (152) in a clamping area (120) of the wet-side surface (124) follow a contour of the clamping area (120), in particular a circular shape. The valve diaphragm (100) according to any one of claims 1 to 5, wherein the ratio of the mean distance (dMax) between adjacent microprotrusions (164) or adjacent microridges (152) and a mean depth (t) of the microstructure (150) is between 0.2 and 0.9, in particular between 0.2 and 0.

6. The valve diaphragm (100) according to claim 5, wherein a rise (156) facing the actuating axis (S) of at least a number of the raised microridges (152) is steeper than an associated rise (158) facing away from the actuating axis (S). The valve diaphragm (100) according to any one of claims 4 to 7, wherein at least a portion of the raised microridges (152) in a sealing ridge region (132) extending through an actuating axis (S) of the wet-side surface (124) follow a longitudinal contour of the sealing ridge region (132).The valve diaphragm (100) according to claim 8, wherein a rise (156) facing the central longitudinal axis (M) of the sealing rib region (152) of at least a number of the microribs (152) is steeper than an associated rise (158) facing away from the central longitudinal axis (M). The valve diaphragm (100) according to any one of claims 1 to 9, wherein a mean maximum distance (dMax) between two opposing microribs (152) of the associated microrecess (154) of the. Microstructure (150) between 10 pm and 500 pm, especially between 10 and 100 pm, lies.

11. The valve diaphragm (100) according to any one of claims 1 to 10, wherein the at least one microstructure (150) comprises a continuous recessed microsurface (162) which surrounds microprotrusions (164).

12. The valve diaphragm (100) according to claim 11, wherein the micro-protrusions (164) increase the contact angle of the wet-side surface (124).

13. The valve diaphragm (100) according to any one of claims 1 to 12, wherein the functional area (130) of the wet-side surface (124) has a first contact angle with a first microstructure (150), and wherein the clamping area (120) has a second contact angle with a second microstructure (150), which is smaller than the first contact angle.

14. The valve diaphragm (100) according to any one of claims 1 to 13, wherein the microrecesses (154) or the at least one recessed microsurface (162) are at least partially convex.

15. The valve diaphragm (100) according to one of claims 1 to 14, wherein a walking area (136) of the wet-side surface (124) is located between the clamping area (120) and a central (134) through which the actuating axis (S) The valve diaphragm (100) according to claim 15, wherein concentric subregions (180, 182, 184) of the flexing region (136) of the wet-side surface (124), in particular an intermediate region (182) and edge regions (180, 184) of the flexing region (136) surrounding the intermediate region (182), have at least two different microstructures (150). A diaphragm valve comprising the valve diaphragm (100) according to any one of the preceding claims.

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