DE2821167C3 - Membrane to keep two neighboring rooms separate - Google Patents

Description

As is known, membranes have a wide variety of uses. When used as regulating diaphragms, they transform the control pressure of a control medium into a rod force / ur actuation of a switching, rule or Display device. Conversely, pump diaphragms have the task. a rod force into a fluid pressure to convert. Finally, elastic separating membranes should be used in pressure accumulators and pressure equalization vessels a change in volume between two almost identical rooms with the lowest possible intrinsic resistance enable. Finally, membranes are part of shut-off valves, e.g. B. Diaphragm Valves And Meffibrarian Gate Valves. Every use case

places specific requirements on the membrane to be used - on the shape, the strength, the Flexibility and the possible hub.

In the case of the membranes known up to now, considerable changes in shape occur during a working stroke stress the membrane material heavily. It is also known by the different shape of the Membrane, e.g. B. plate, beading, plate or hat shape, the particularly harmful deformation by fulling like this to be kept as short as possible in order to achieve the longest possible service life. This in its basic form more or less flat membranes generally allow only a very limited stroke. at large strokes would stretch the material and thereby put additional stress on it. Allow rolling diaphragms In contrast, a large stroke, the membrane thickness and the strength of the material that can be used however, there are limits due to the strong changes in shape.

Other membrane constructions are relatively thick and show in cross-section a more or less curved arcuate course running in one direction. You are like that clamped between housing parts that between the outer and the middle clamping point in the top and bottom corner position the arched course is retained. They also suffer from that Disadvantage that only a small stroke can be used to avoid turning over.

All previous diaphragms that have an arcuate cross-section of part of the diaphragm ring surface or the have the entire annular membrane area between the outer and central clamping point, limit the Sequence of movements on this membrane area; the center of the membrane cannot take part in the change in shape participate, as they are rigid and intended for a fixed connection of the adjusting elements / ur control of the membrane is. So only part of the entire membrane surface, a circular section, is used for the sequence of movements utilized.

The invention relates to a membrane for separately holding two adjacent spaces identical or different pressure from flexurally elastic material of a constant, defined basic shape with or without Gewebeein- ode ^r pad, the flange-like rim is clamped between two G ^ iäuseteilen, wherein the immediately adjoining section forms a circumferential ring vault on the side facing the clamping edge in all positions of the movement.

A membrane of the design described above is known from DEAS 25 10 428. This includes a shut-off valve with a straight throughflow and r.:with a valve housing arranged at an angle to the flow direction, the valve seat having a clamped between the housing lower and upper part, in its middle area as a likewise inclined valve closure piece that can be pivoted from the open to the closed position like a flap formed membrane and with a valve spindle which is arranged obliquely to the direction of flow and is articulated to the center of the valve wear piece. The Merrmran has between its clamped edge and the valve closure piece a concave curvature in the form of a channel when viewed from the valve seat in the open and closed positions. This diaphragm, created for " a shut-off valve of a special design, is not symmetrical in cross-section or in top view, because the closure piece to the plane of the one

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is arranged obliquely and the arc length of the curvature of the membrane is seen in the direction of flow steadily reduced in size from one end of the membrane to the other.

From US-PS 32 07 472 it is known in a membrane in a valve for a tap that the flange-like clamping edge of the membrane drawn inward and between the cover and the metallic part of the closure piece is clamped

The present invention is based on the task of ι ο to create a membrane that allows a variety of uses with a uniform basic shape, in their Movement is subject to only minor changes in shape when foreign components and supporting organs are omitted and in relation to their diameter and their surface a large one, each according to their use modified hub allows. In particular, it is intended for sealing under high differential pressure standing media and the print side can be freely selected. In addition, the aim is the elasticity and reducing the strength of the membrane or reducing the size of the membrane working area Breakthroughs for the adjustment elements for the control are avoided.

To solve this problem, a membrane is used to keep two adjacent rooms separate same or different pressure from flexible elastic Material of permanent, defined basic shape with or without fabric inlay or overlay, their flange-like edge is clamped between two housing parts 3 <>, the directly attached to it subsequent section on the side facing the Einspannranci in all positions of movement forms a circumferential ring vault, proposed according to the invention that with increasing wall thickness of the Ji Diaphragm in the direction of the clamping edge towards its center in each case the annular vault of the membrane below guide and the convex curvature of the membrane upper side in the middle area of the membrane into a reverse curve surrendered. ■ ">

A membrane with these characteristics is versatile. So it can be used as a stabilizer for lifting, damping or pushing. It can also be used as a membrane in a variable speed drive or as a membrane in a shut-off valve. ⁴ ^

A membrane with the features according to the invention len has the following properties:

1. If it has a large lifting capacity, it has at its Movement only changes its spatial shape slightly, so that there are no turns or twists appear:

2. when a load from above the resting on the diaphragm control pressure forces due to the dome shape to an outer annular _w attacking reaction force and in the middle of the membrane tion force to a point-like acting reac, so that, in use in a variable speed drive or a shut-off valve cm slightly higher control pressure is sufficient. _h o to generate the necessary higher pressure and sealing forces in the area of the middle of the membrane;

3. The diaphragm is on top of it in the event of direct pneumatic or hydraulic actuation entire surface applied evenly, so that the specific stress per Area unit reaches its minimum and thus a locally strong load as with membranes with adjusting devices acting in the middle is avoided;

4. The membrane is at an initiated change of position supported on its entire surface;

5. when a liquid is used to actuate the diaphragm, there is no counterpressure no further or additional stress on the membrane material;

6. the membrane plant, e.g. B. rubber, is under Operating stress is no longer subjected to tension in any phase, but only to compression and thus in the cheapest and most gentle way for an elastomer at all;

7. There is no friction between the membrane and the housing, causing mechanical destruction is avoided;

8. Because of the arching effect of its arches, the membrane is suitable for high pressure without changing its shape to withstand;

9. a liquidity barrier for the membrane material used at higher temperatures because of the required low pressure difference between control and operating medium does not or does not really annoying noticeable,

10. The membrane itself takes the lead and Positioning of the closure piece or the middle of the membrane and not one on the from Ventils'tz seen facing away from the diaphragm side lying special in previous diaphragm valves necessary guide device;

11. when the membrane is acted upon by a Inert hydraulic fluid is also a high level of protection against aging, for example against atmospheric oxidation or that under the influence of ozone under static or dynamic stress caused cracking given. As is well known, one caused by aging progresses Destruction of membranes in shut-off valves regularly from the outside to the inside, i.e. towards the operating medium. This by the invention The anti-aging properties achieved using the membrane are also of particular importance because anti-aging agents are added to the rubber only under static load, but not under dynamic dem Grant rubber a protection.

In a further embodiment according to the invention proposed that, seen in cross section, the arcuate convex curvature curves of the ring vault intersect in the middle of the membrane. With this proposal, the entire top of the membrane exists from the ring vault. However, this also means that the curves are in extension of the curved membrane top and cut into In the middle area there is a convex rounding of a small area. This will be discussed in further erfindunjsgemäP.T embodiment proposed that on the upper side of the membrane, the convex surface of the ring vault is more than about 70%, in particular more makes up 90% of the total membrane surface. This proves the further advantages achieved:

12. For a given diameter, the membrane has in all its positions while maintaining the Vault shape because of the largest possible design of the membrane arches a large stroke, the

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only leads to a very small deformation or change in the shape of the space;

13. The stroke is greatest in the membrane center and constantly decreases towards the outside. The entire membrane surface is involved in the hub, but everyone Point on another circular point described concentrically around the center of the membrane is located on the outside with a smaller way. The membrane thus displaces one Working stroke only a relatively small volume, so that only to an equally large one small consumption volumes at tax or Working medium leads. When a pneumatic drive is used, there is therefore less air consumed than with a drive with the same stroke. in the previous manner a cylindrical space must be filled with one working stroke.

The solution according to the invention is particularly advantageously used as a valve in which the membrane is through a hydraulic fluid is applied. In this valve, a displacement piston works against the above the membrane is filled with a liquid space. Because of the center of the membrane ever larger bow thrust is already due to a relatively small volume displacement a great stroke achieved. The required actuation forces are also extremely low, since the area of Displacement piston and diaphragm are in a reduction ratio.

The advantages of the direct pressurized membrane already mentioned can now be used for the first time can be used with a diaphragm valve. The usually more or less large selectively Attacking actuating forces are replaced by one that is distributed over the entire membrane surface Force with minimal stress per unit area; occur in the diaphragm material in each actuation phase exclusively compressive stresses - no more tensile stresses; effective through the center When the arc thrust is developed, all forces acting on the membrane surface, depending on the point of application, become whole or partially for the closing movement and the necessary pn nirhtträftp aiicoronij * ^ ;; «J;> E membrane valve is suitable as a high-pressure valve, as the diaphragm is constantly affected by the hydraulic fluid over its entire surface is supported and the membrane is always so stable due to its vault shape to the To be able to transmit sealing forces.

Begin in a further embodiment according to the invention the inner and outer limiting curves of the ring vault from the outer edge with a steep one (more than 45 °) angle.

In a further embodiment according to the invention, the entire upper side of the membrane is used as a work surface educated. It is free of actuating devices or parts connected to the membrane of that. As a result, the entire top of the membrane takes part in the change in shape, so that the Curvature effectively extends unhindered to the middle of the membrane and also for actuating the Membrane in the middle area of the membrane is effective.

In order to achieve an additional reduction in the deformation of the diaphragm when it is actuated, however also in order to be able to carry out this with a small outer diameter, furthermore to make the membrane in Improved connection with hydraulic actuation between the upper part of the housing and the lower part of the housing To be able to clamp and seal is further proposed embodiment according to the invention that the flanged clamping edge is drawn inwards is and in addition to the outside by a small amount protrudes.

In the case of a ⁴ membrane, which is clamped as a valve between a housing part through which the medium flows, and an upper housing part accommodating the valve actuation, it is proposed in a further embodiment according to the invention that a space filled with a pressure medium be present between the membrane side and the inner surface of the upper housing part, that actuates the diaphragm directly. This pressure medium can be compressed air. However, a liquid such as glycerine, water or oil is particularly advantageous as the pressure medium. When pressure is exerted, the hydraulic fluid then affects the entire membrane surface and actuates the membrane. The pressure

m can through sin? druckerzsu ^ snds device can be introduced via a line into the space between the upper part of the housing and the upper side of the membrane. Particularly advantageously, an axially displaceable piston protrudes into the space between the upper side of the membrane and the inner surface of the upper housing part, which increases the pressure of the liquid when it moves in the direction of the membrane and thus actuates the membrane indirectly via the liquid. This solution is particularly ^r vorteilha \ because the plunger may be by a spindle, but actuated by a solenoid, because the exerted forces need only be slight. The solution of controlling the membrane via a liquid now makes it possible for the space filled with the pressure medium between the membrane top and the inner surface of the housing top to be provided with a manometer connection for pressure and position indicators.

The invention is explained in more detail in the drawing using a few exemplary embodiments.

Show it

IA to ID the membrane in vertical section in different positions,

F i g. 2 g of a horizontal section through the membrane 1. 1 lb corresponding to the local line 11-11,

F i g. 3 the view of the membrane top,

4 shows a membrane according to FIG. 1 as part of a Variable speed drive,

F i g. 5 two membranes according to FIG. 1 as lifting cushion,
F i g. 6 a membrane in connection with a thrust actuator,

F i g. 7 shows a vertical section through a membrane in connection with a lifting cushion,

F i g. 8 a vertical section through two membranes as lifting cushions,

F i g. 9 a vertical section through two membranes, also as lifting cushions,

F i g. 10 in vertical section a membrane as a valve in a valve housing.
According to FIG. 1A, the membrane 10 consists of elastomers, in particular rubber. Fig. IA shows the upper position, F i g. 1B the basic position. The basic position has the spatial shape of the production and thus the vulcanization shape. Fig. IC shows the lower position. FIG. ID shows in full lines the upper position according to FIG. IA and in dashed lines the lower position according to FIG. IC From FIGS

its clamping edge 12 and the center 11 of a obe'fltälb Einspannrahdes lying circumferential concave Rifiggewolbe R has the UIID Wänddicke of the annular vault in direction vcun clamping edge 12 towards the center M of the membrane on the road increases. From the representation in FIGS. 1A to 1D it can be seen that the membrane 10 is exposed to only slight formations during its actuation, in particular whale bait, roller movements are avoided. ID with the representation of the two extreme positions. F i g. 1D also shows that the diaphragm allows a large stroke when actuated, in spite of slight deformation.

Fig. 1 also shows that the wall thickness of the Ring vault in the direction from the clamping edge to the center of the membrane is constantly increasing.

In Fig. IC it is shown that the upper outer annular arch surface Fl. whose diameter is shown. is larger than the lower or inner annular arch surface F2, the diameter of which is also shown, in the projection by more than 20%.

F i g. 2 shows that in the three-dimensional shape of the membrane produced according to FIG. IB in a section H-II parallel and following the flange 12 as a clamping edge, the area F3 of the circular ring is equal to the area FA of the circle located in the center M of the membrane 10 or is approximately the same. By this provision it is achieved that the membrane stabilizes itself during its movements and no special guidance of the membrane is necessary.

The F i g. 1A to 1D show that on the membrane upper side 13 of the membrane, the curved surface 14 of the annular vault R makes up almost 100% of the total surface of the upper side. Fig. 1 shows that, seen in the cross section shown there, the upper left limiting curve 14Z. and the upper right limiting curve 14 /? cut in the middle of the membrane at an acute angle. 1A to ID further show that the outer limiting curves 14 and the inner limiting curves 15 of the annular vault have a spiral segment shape. this

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an arc shape is present, with the ascending Diaphragm arch in the vicinity of the clamping edge 12 changes its direction only slightly. This the Ideal shape of a pressurized area corresponding shape is both when pressurized from below as well as from above due to the somewhat greater elasticity of the outer area During the transition to the lower end position, the steeper branch of the membrane arch also prevents the reverse from happening stronger turning, because the length of the steep arch branch leads to a smaller local change of direction leads, but altogether will allow the permissible movement of the membrane center- which in turn pressure load existing either below or above the membrane continues to act on one Turn in the opposite direction, because with this downward stroke the membrane in the outer area has a circular shape endeavors to take the middle part on the other hand due to its greater thickness and thus greater rigidity, the retention of a flatter one Shape favors.

Opposite is a shaping of the membrane sheet as a semicircle or circle segment in the Vulkanisationsstellung by the proposal of the spiral shape with a steep outer branch of the curves 14 and 15, which pass into Bogenförrn irr the upper part 16 of the EiiTspaftnraiides 12, the shape change in this Übefgangsbefeich, which is known in other solutions are subject to particular stress, limited to a minimum.

Fig; IB with the depiction of the vulcanization position of the membrane shows ₍ that the upper edges 14L and 14R intersect at the level of the upper side 16 of the clamping case 12 at point 18. This intersection 18 is to be indicated as the Merribran center in the following consideration 1A with the upper position of the diaphragm shows that the aforementioned intersection point 2/3 is higher than the intersection point in the illustration in FIG. 1C. The two end divisions are also clear from FIG At the center of the diaphragm in relation to the clamping plane determined by the inner clamping edge during the closing movement according to Fig. IC to a third below the clamping plane and in the upper end position according to Fig. especially in the outer area, more strongly reduced than with a stroke that is half above and half below de r clamping plane would play.

FIGS. 1A to ID also show that none of the rigid middle area is present. Previously known membranes have a pronounced dimensionally stable center piece, so that their central area does not contribute to the change in shape that enables the diaphragm stroke can, but the change in shape occurs exclusively in the smaller circular diaphragm working area plays.

In the present membrane, the entire area of the membrane is the membrane working area. Every change in position of the diaphragm thus leads to a simultaneous one Change in shape of the entire membrane surface. The membrane center performs the largest stroke. while the stroke continues to decrease towards the outside. According to the present solution is thus a large stroke of the membrane center with a small one

Diaphragm leads to their versatile use, for example for a diaphragm actuator. Even significantly less air is required for a stroke with pneumatic actuation than with previous diaphragm drives in which the middle part of the diaphragm is designed as a rigid plate and so that a displacement of a cylindrical space must take place.

The membrane in which the Arch shape or the ring vault is retained, allows pressure loads of more than 10 bar. Be it notes that with previous diaphragms, 10 bar regularly represent the top pressure load.

3 shows an upper side of the membrane in which the upper limiting curves 14L and 14A, shown in dashed lines, merge into a concave curve 17 in the region of the middle of the membrane. With this solution it is found that the outer curved surface of the ring vault makes up the greater part of the surface of the membrane and the surface F6, which is determined by the curve 17 of opposite inclination, is very small compared to the surface F5

Fig. 1 also shows that at the bottom of the Membrane, the limiting curve emanating from the edge

ven 15Z, and 157? in the middle of the membrane in a Umkehfkufve 20 pass over the middle Area of the membrane represents a segment of a circle. Furthermore, Fig. 1 shows how all the others Figures that the flange-like clamping edge 12 is drawn in and in addition by a small amount Protrudes according to measure. Also, as Fig. 1B shows, the flange-like edge 12 is provided with an embedded reinforcing ring 21.

F i g. 4 shows that the membrane according to FIG. 1 application takes place as a control drive. For this purpose, the membrane is clamped between an upper housing 21 and a lower housing 22 with the proviso that the two housings ί! 1 and 22 the flange-like edge 12 grip around the membrane on four sides, so that a particularly good clamping and sealing of the Clamping edge takes place. Between the top of the membrane and the housing 21 is via the connection 23 a pressure medium introduced, which the membrane Kptäticrt c £ \ dsß over 2! Γΐ £ Γΐ sr! the Membruiiuiitcrseiic adjacent shoe 24 is actuated against the pressure of a helical spring 25 of the plunger 26. At 27 is denotes a vent.

F i g. FIG. 5 shows the arrangement of two membranes 10, with their undersides facing each other. Both membranes IO are held by a common ring 28, with pipe clamps assigned to each membrane 29 and 30 provide the necessary security. In the space between the two membranes, the Port 31 is filled with a pressure medium. This can also be compressed air. The arrangement of FIG. 5 can serve to lift an object 32 resting on the upper membrane 10 or whose vibrations are dampened. The lower membrane 10 is supported on a stool 32, which over a flat iron 33 is connected to a foundation 34.

FIG. 6 shows a further control drive comparable to that according to FIG. 4, but with the proviso that the lower side of the membrane 10 in the area of its center between the arches R has an approximately elliptical thickening 35 in cross-section, the outer edge 36 of which lies in the area odc below the clamping edge 12 and laterally in a part the bulge R protrudes so that an undercut ■ is present. The thickening 35 is provided with an inner metallic reinforcement 37, which is designed in the shape of a lens and, as shown in FIG. 6 is in one piece with a plunger 38. The membrane is clamped between the two housing parts 21 and 22 in basically the same way as that of FIG. 4 has also been described with the arrangement according to FIG. 6 there are two pressure chambers 39 and 40 to which a pressure medium can optionally be applied via associated connections 23 and 27.

F i g. 6 shows particularly clearly that the thickening 35, in which the reinforcement 37 is present, lies in an area outside the effective area of the annular arch R so that the membrane has the properties as shown in FIG. 1 have been described.

F i g. 7 shows that the membrane is designed as a thrust pad and is located inside the housing 21 in FIG Connection with a ring 41 is attached The lens-shaped reinforcement 37 is with an outward protruding, threaded pin 42 is provided, which is in a resting on the foundation 34 Carrying body 43 is screwed in. By introducing a pressure medium via connection 23 into space 39 the object 32 can be raised or lowered accordingly. But even without an arrangement Pressure medium in space 39, the membrane can serve as a damper,

F i g. 8 shows that as a modification of FIG. 5 two with their undersides opposite membranes 10 in a thickening 35, as described for FIG has been, each have a lens-shaped reinforcement 37, which on all sides from the material of the membrane

ίο are surrounded. Thus, the thickenings can be mutually exclusive nudge.

Fig. 9 shows that - deviating from the representation in Fig. 8 - the two membranes for their function as thrust cushions or cushioning cushions with their upper sides facing each other. They are held by the common ring housing 28 in connection with a each membrane associated ring 41, the outside e!: ie has a circumferential groove which the inwardly protruding flange 12 of the membrane and the lower annular surface 44

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Both end faces are provided with an inwardly directed flange 45. In the same way as to Fig. 7 described, have the reinforcements 37 in the Thickening below the clamping edge a lens-shaped reinforcement 37, which extends outward into a threaded pin 42 which is screwed into a foot 43 continues.

Fig. 10 shows the membrane 10 in the application a valve with the valve housing, consisting of the housing 45 through which the medium flows and the Upper housing part 46, which carries the actuation with the handwheel 47. The connection with the upper part of the housing takes place in the usual manner, not shown in the drawing. The housing 45 has a ring part 48 with an outwardly open groove 49, which the inwardly protruding flange 12 of the membrane as well the underside 44 engages around. The lower inner edge 50 of the upper housing part 46 engages around the Flange part 51 protruding slightly outward beyond the membrane. The inwardly protruding Mounting flange of the membrane initially leads to small dimensions of the housing.

Also, rubber suffers from the phenomenon of creep; H. it deforms under pressure or Tensile stress as a function of time. In the case of an outer chamber, the direction of pull falls from the The medium acted upon by the membrane and the direction of creep together. With the interior chambering shown on the other hand not. Here the medium has to crawl around a corner, as it were, which is caused by the significantly larger frictional forces is greatly reduced. The one with the flange protruding inward achievable interior chambers therefore have great advantages.

In its center, the valve has the thickening of the lens-shaped cross section described for FIG 35 with the inner lens-shaped reinforcement 37, it being noted, however, that - different from the Diaphragm shape in Fig. 8 - this thickening is also present at the level of the flange 12 of the membrane 10 With this design, the functionality of the membrane is not impaired as the ring vault only a partial stroke, namely the stroke upwards, must allow and the thickening 35 with the reinforcement 37 the Deformation of the ring vault is not impaired as it is outside of its range of action with the limited stroke The valve 10 is designed as a partial lift valve. In order to create an optimal solution here, the in Fig. 10 shown closed position with the plant of

as a thickening formed locking piece 35 art the valve seat ring 52, the vulcanization position of the membrane as shown in Fi g. IB. There starting from this vulcanization position, the upward stroke movement is two thirds of the total movement can make out, and only a stroke of D / 4 is required to release the flow cross section of a valve is, the deformation of the membrane from the closed position, as shown in Fig. 10, in the Open position very low.

The direction of flow of the medium in the housing 45 is indicated in the direction of arrow 53 with the result that the pressure of the medium in all positions of the diaphragm is directed towards the underside of the diaphragm. Between the top of the membrane and the inner surface 53 of the upper housing part 46 is a Liquid 54 present. This can be any inert liquid. There are also coming other incompressible liquids in question. That

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iianuiau τ / iai iniL cmc! ojjlliuci JJ, UIe has the displacement piston 56 at its front ends, which is sealed in the upper housing 46 via the cover 57, 57a. Furthermore, there is a leakage ring 58 between the seals 57, 57a, via which the liquid 54, provided it passes through the seals 57, 57a, can be drawn off. If the piston 56 is moved downwards, this exerts a pressure on the liquid 54, which pressure is distributed over the entire surface of the membrane and moves the membrane downwards. Since the pressure of the medium flowing in the direction of arrow 53 presses on the underside of the diaphragm and thus lifts it off the valve seat 52, the diaphragm 10 is in the open position when the piston 56 is raised. By moving the piston 56 down via the handwheel 47 and the spindle 55, the pressure on the control fluid wedge 54 is greater. As soon as the pressure of the liquid 54 is greater than the pressure of the medium present in the housing 45, the membrane 10 moves into the closed position. F i g. 10 thus shows that the membrane 10 is hydraulically supported on both sides. Urn to operate the valve, it is only necessary that * 'Her pressure of the liquid 54 is larger by a small amount than the pressure of the medium or the fluid flowing in the housing 45 and is available there. The piston, which is immersed in the hydraulic fluid, therefore only needs to displace a small volume. Accordingly, it can be kept relatively small. The required actuation forces are also extremely low due to the resulting smaller reduction ratio. Since at the same time the outer surface of the ring vault is larger than the inner surface in the projection effective for the application of pressure, the pressure of the liquid can even be lower than that of the medium in the housing 45.

In addition 7 sheets of drawings

Claims (7)

Patent claims: 1. Membrane for keeping two adjacent spaces of the same or different pressure separate from flexible material of a permanent, defined basic shape with or without fabric inlay or overlay, the flange-like edge of which is clamped between two housing parts, the directly adjoining section on the side facing the clamping edge in All positions of the movement forms a circumferential ring vault, characterized in that with increasing wall thickness of the membrane in the direction from the clamping edge (12) towards its center, the ring vault (R) of the membrane underside (11) and the convex curvature of the membrane top in the middle area of the membrane into a Reversal curve (20) passes. 2. Membrane according to claim 1, characterized in that, seen in cross section, the arcuate convex curvature curves (14Z-, i4R) of the annular vault (R) intersect in the middle of the membrane. 3. Membrane according to claim 1, characterized in that on the membrane upper side (13) the convex surface of the RinggewCibes (R) makes up more than about 70%, in particular more than 90% of the entire membrane upper side (13). 4. Membrane according to claims 1 to 3, characterized in that the inner and outer limits, curves (15, 14) of the annular vault (R) from the outer edge a "s with r ^; nem steep (more than 45 °) WinkH kick off. 5. Membrane according to claims I to 4, thereby characterized in that the entire, facing away from the clamping edge Mi: mbranoberseite (13) as a work surface is trained. 6. Membrane according to claims 1 to 5, characterized in that the flange-like clamping edge (12) drawn inwards and also protrudes outwards by a small amount. 7. Membrane according to claims 1 to 6. the a! S Valve between a housing part through which the medium flows and one that receives the valve actuation Housing upper part is clamped. characterized in that between the Membrar.oberseite (13) and the inner surface (53) of the housing part (46) a space filled with a pressure medium (54) is present, which is the membrane immediately actuated.