Membranventil

Abstract

Diaphragm valve, comprising at least one valve body (10) having at least one inlet (12), at least one outlet (14), at least one flow channel (16) and at least one shut-off bar (18) dividing the flow channel (16) into channel sections, a diaphragm (20) resting on a circumferential sealing seat (22) of the valve body (10), an actuator (24) with an actuator housing, wherein the actuator (24) is coupled to the diaphragm (20) to press the diaphragm (20) against the shut-off bar (18) to close the valve, and a fastening unit for releasably locking the actuator (24) to the valve body (10), wherein the fastening unit has a bayonet fitting (30) and an additional central tensioning unit (32), wherein the tensioning unit (32) generates an axial clamping force. characterized by the fact that the drive housing is designed in multiple parts and has an attachment housing part (28) on which the tensioning unit (32) is supported, wherein the attachment housing part (28) and the bayonet lock (30) are coupled to each other in a rotationally fixed manner via an axial guide (44, 46).

Description

[0001] The invention relates to a diaphragm valve with a valve body having at least one inlet, at least one outlet, at least one flow channel and at least one shut-off web which divides the flow channel into channel sections, a diaphragm which rests on a circumferential sealing seat of the valve body, a drive with a drive housing, wherein the drive is coupled to the diaphragm in order to press the diaphragm against the shut-off web in order to close the valve, and a fastening unit for releasably locking the drive to the valve body.

[0002] The invention relates to all types of diaphragm valves, with manual, pneumatic, hydraulic or electrically operated actuators, which usually move the diaphragm via spindles and cause the valve to open or close.

[0003] The actuator is designed as a separate unit, usually detachably attached to the valve body. The diaphragm sits between the valve body and the actuator.

[0004] Traditionally, the diaphragm has been clamped to the valve seat by attaching the actuator housing to the valve body with several screws distributed around the circumference, with the diaphragm clamped between them. The problem with this method is that the screws do not clamp the diaphragm evenly, as not all screws can be tightened to exactly the same compression distance. However, uneven compression of the diaphragm can lead to leaks between the valve body and the diaphragm, as well as to a reduction in the service life of the diaphragm itself. Furthermore, the numerous screws are easily lost during assembly or disassembly of the actuator, or they could fall into the flow channel.

[0005] DE 101 53 362 A1 proposes a mounting unit with a central union nut for connecting the actuator to the valve body, which enables constant compression of the diaphragm. However, especially in overhead installations, it is not always easy to assemble the sometimes heavy diaphragm valves, as the valve body is usually installed in a drive train and, if necessary, only the diaphragm needs to be replaced.

[0006] Furthermore, diaphragm valves are known from US 2014 / 0 020 769 A1, US 2014 / 0 021 392 A1, DE 10 2009 023 002 A1 and DE 10 2008 045 857 A1.

[0007] The object of the invention is to create a diaphragm valve in which the assembly of the actuator and the replacement of the diaphragm are simplified and accelerated and a uniform and process-reliable diaphragm clamping is ensured.

[0008] This object is achieved in the diaphragm valve of the type mentioned at the outset in that the fastening unit has a bayonet lock and an additional, central tensioning unit, wherein the axial clamping force generated by the bayonet lock can be increased, preferably continuously, by the tensioning unit. The drive housing is designed in several parts and has an attachment housing part on which the tensioning unit is supported. This means that the attachment housing part has the counter surface to the support surface. Furthermore, the attachment housing part and the clamping ring are coupled to one another via an axial guide in a rotationally fixed but axially displaceable manner, such that the bayonet lock can be released and closed by rotating the attachment housing part, thus allowing easy access for assembly.

[0009] With the diaphragm valve according to the invention, the actuator can be mounted very quickly, even upside down, using the bayonet lock. However, a bayonet lock can result in the parts clamped between it not being sufficiently compressed, meaning in this case, the diaphragm is not sufficiently sealed. Furthermore, a higher axial displacement force, which could be achieved with a long twisting path of the bayonet lock, carries the risk that the interposed diaphragm will be subjected to shear stress by the twisting movement and become defective. In the invention, the bayonet lock serves for quick fastening, and the tensioning unit then ensures that the required tensioning and clamping force is exerted on the diaphragm. A central tensioning unit, rather than numerous screws to tighten, ensures a uniform additional tensioning force applied by the tensioning unit.

[0010] One embodiment of the invention provides that the tensioning unit is a union nut, i.e. a part that is very easy to manufacture.

[0011] The bayonet closure may also have a clamping ring with protruding claws that engage behind projections on the valve body.

[0012] The tensioning unit can engage the clamping ring and move it axially. Thus, the tensioning unit and bayonet lock are connected via common parts, reducing installation space.

[0013] The tensioning unit, for example, has a support surface that axially rests on the actuator housing to press the actuator housing axially toward the diaphragm. The tensioning unit thus acts like a pair of pliers, with one end being the actuator housing and the other end being the valve body, which is coupled to the tensioning unit via a bayonet lock.

[0014] The mounting unit and the drive housing can be designed so that the diaphragm is visible from the side along its circumference. This important feature allows even small leaks to be detected immediately, which is not possible with the prior art, especially when using a union nut. Here, the diaphragm is completely installed, meaning it cannot be seen from the outside. With the invention, however, the design of the diaphragm or the diaphragm material can also be determined from the outside, for example, via inscriptions on the edge of the diaphragm. This facilitates diaphragm replacement if the last diaphragm used can be identified from the outside.

[0015] The top housing part not only serves to allow the tensioning unit to engage with it, but it also has a surrounding edge with which it presses against the diaphragm and presses the diaphragm against the sealing seat.

[0016] The support surface of the tensioning unit rests, for example, on a shoulder of the attachment housing part.

[0017] If the top housing part is cup-shaped or bell-shaped, its hollow interior can accommodate the attachment of a lifting spindle to the diaphragm. Typically, but not necessarily restrictively, there is a coupling part between the diaphragm and the lifting spindle that positively accommodates the lifting spindle.

[0018] The add-on housing section with steps or special surfaces may be more complex to manufacture. Therefore, it is designed as a separate part coupled to a main housing of the drive. This main housing is axially adjacent to the add-on housing and connected to it, but in particular, is designed to be rotatable relative to it.

[0019] In addition, the membrane can be coupled to the top housing part in a rotationally fixed manner via a positive connection, for example via one or more protruding tongues, which then has corresponding recesses.

[0020] Furthermore, the top housing part can have a centering feature for the membrane it houses. This can be achieved, for example, using a rotationally symmetrical centering collar.

[0021] The bayonet closure can be a clamping ring with wing clamping claws that axially engage around a radial flange section on the valve body, so that the wing clamping claws have the shape of a horizontal "U" in radial view, with one leg formed on the clamping ring.

[0022] An alternative embodiment provides that the bayonet closure is a clamping ring with radially projecting hooks that grip valve seat-side, for example mushroom-shaped holders below the mushroom head.

[0023] It should be emphasized that the diaphragm valve according to the invention is not limited to two-way valve bodies, but can of course also be used with multi-function valve bodies, including diaphragm valves with multiple actuators and multiple shut-off bars.

[0024] Further features and advantages of the invention will become apparent from the following description and the following drawings, to which reference is made. In the drawings: - Fig. 1 a first embodiment of the diaphragm valve according to the invention, - Fig. 2 a second embodiment of the diaphragm valve according to the invention, - Fig. 3 an exploded view of the diaphragm valve according to Fig. 1 in the area of ​​the valve body and the fastening of the actuator housing, - Fig. 4 an exploded view of the diaphragm valve according to Fig. 2 in the area of ​​the valve body and the fastening of the actuator housing, - Fig. 5 a sectional view through the diaphragm valve according to Fig. 1 in the area of ​​the valve body and the fastening of the actuator housing, and - Fig. 6 a sectional view through the diaphragm valve according to Fig. 2 in the area of ​​the valve body and the fastening of the actuator housing.

[0025] In Fig. 1 shows a diaphragm valve which has several components, essentially a valve body 10, which is designed here as a two-way valve body, with an inlet 12 and an outlet 14 as well as a flow channel 16 connecting the inlet 12 and outlet 14, see Fig. 3, and a drive 24.

[0026] The flow channel 16 has two channel sections that begin on both sides of a barrier bridge 18.

[0027] The shut-off bar 18 is usually an edge of an overflow opening between the channel sections, which, however, can optionally be closed by a membrane 20.

[0028] The membrane 20 covers an opening above the shut-off bar 18 in the valve body 10, which Fig. 3 at the reference numerals 16, 18. This opening is surrounded by a flange-like, annular sealing seat 22 on the valve body 10, against which the diaphragm 20 rests in a circumferentially closed manner.

[0029] A drive 24 is shown for switching the diaphragm 20 and thus the valve, which moves it up and down. The drive 24 is, in particular, a linear drive that can be operated manually, pneumatically, hydraulically, or electrically.

[0030] The actuator 24 has an outer housing which has several parts, namely, among others, a main housing 26, which is preferably cylindrical, and an attachment housing part 28 which is located between the main housing 26 and the valve body 10 and which in the present case is essentially bell-shaped.

[0031] The connection between the drive housing and the valve body 10 is designed as a removable connection, namely via a bayonet lock 30 on the one hand and a tensioning unit 32 on the other hand, which together form a fastening unit.

[0032] The bayonet closure 30 comprises a clamping ring 34 with projecting claws, according to the Fig. 1 and Fig. 2 with so-called wing clamping claws 36, which have the shape of a horizontal "U" and engage behind the valve body-side extensions, here radial flange sections 38, when they are first inserted axially into gaps 40 and then rotated behind the flange sections 38. Corresponding wedge surfaces ensure an axial preload, which is generated when the bayonet lock 30 is locked.

[0033] The clamping ring 34 is centered on the inside against a cylindrical surface 42 of the top housing part 28 (see Fig. 3 and Fig. 5) and is also connected to the top housing part 28 via axial guides, here axial extensions 44 on the top housing part 28 and corresponding grooves 46 on the inside of the clamping ring 34, in a rotationally fixed but axially displaceable manner. The top housing part is pushed axially downwards.

[0034] A closed peripheral edge 48 on one end face of the top housing part 28, here on an outwardly projecting annular flange 80, presses the membrane 20 at its peripheral edge tightly against the sealing seat 22 (see Fig. 5).

[0035] The membrane 20 is coupled to the top housing part 28 in a rotationally fixed manner by means of a positive connection, namely Fig. 3 visible projections, which are designed as laterally projecting tongues 50 and sit in corresponding recesses 52 in the attachment housing part 28.

[0036] How Fig. 3 and Fig. 5, the annular flange 80 of the attachment housing part 28 has, radially outside the circumferential edge 48, a centering collar 54 projecting axially in the direction of the diaphragm 20, against which the diaphragm 20 rests and by which it is centered. The recesses 52 are provided only in the centering collar 54, so that the circumferential edge 48 forming a clamping surface is designed without a recess.

[0037] The tensioning unit 32 with a union nut 62 serves to create a fastening unit with the bayonet lock 30 for releasably locking the drive 24 on the valve body 10.

[0038] The tensioning unit 32 is designed as a union nut 62, with an inwardly projecting, closed circumferential annular flange 64, which rests with a support surface 67 on a shoulder 66 of the attachment housing part 28.

[0039] The union nut 62 has an internal thread which receives an external thread of the clamping ring 34 (see Fig. 5).

[0040] In the Fig. 3 and Fig. 4 it can also be seen that the attachment housing part 28 has a sleeve extension 70 with which it penetrates into the interior of the main housing 26 and which serves as a guide for a lifting spindle 72.

[0041] The lifting spindle 72 is moved axially by the drive mechanism or manually.

[0042] At the lower end, the lifting spindle 72 is coupled to the membrane 20 via a coupling part 74, in a form-fitting manner, as the Fig. 3 and Fig. Show 5.

[0043] The main housing 26 comprises a substantially cylindrical outer wall and a screwed-in end wall 76, which forms a guide surface for the attachment housing part 28, more precisely, a pivot bearing surface. The main housing 26 can be rotated as desired relative to the attachment housing part 28, for example, to optimally position the power and / or signal connections.

[0044] How to Fig. 5, the top housing part 28, the actuator 24 and the fastening unit with tensioning unit 32 and bayonet lock 30 form a pre-assembled unit, ie there are no loose parts when the actuator 24 has to be fastened to the valve body 10.

[0045] First, to secure the drive 24, the union nut 62 is turned loosely so that the clamping ring 34 is positioned relative to the top housing part 28, Fig. 5, is moved as far downward as possible. For this purpose, the union nut 62 can be supported on the front wall 76.

[0046] The clamping ring 34 moves downwards until its front end abuts the annular flange 80 of the top housing part 28, which projects outwards like a step. In this position, the actuator 24 is then placed onto the valve body 10. The bayonet lock 30 is then closed, for example by engaging the wing clamping claws 36, whereby the wing clamping claws 36 are easily hooked into the radial flange sections 38 by means of inclined surfaces sliding against one another. The retensioning unit 32 is then actuated by turning the union nut 62. Supported by the step 66, the union nut 62 pulls the axially guided clamping ring 34 upwards, i.e. in the direction of the actuator 24, so that the clamping force is increased evenly and centrally via a single actuation or, in other words, the top housing part 28 is pressed axially downwards.

[0047] As particularly in Fig. 1, when fastened, the membrane 20, or more precisely its peripheral edge in the area of ​​the clamping, is visible from the outside, so that leaks can be detected immediately.

[0048] The embodiment according to the Fig. 2, Fig. 4 and Fig. 6 corresponds essentially to that according to the figures just described, where Fig. 2 the corresponding view of Fig. 1, Fig. 4 the corresponding view of Fig. 3 and Fig. 6 the corresponding view of Fig. 5. The reference symbols already introduced are used again for identical or functionally equivalent parts, so that only the differences will be discussed below.

[0049] In the embodiment according to the Fig. 2, Fig. 4 and Fig.6, the valve body 10 is a multifunctional valve body with multiple inlets and / or outlets. This valve body 10 is also coupled to the actuator 24 via a mounting unit with a bayonet lock 30 and a tensioning unit 32; in principle, there is no difference.

[0050] In this embodiment, however, the bayonet lock 30 is designed differently. Here, the clamping ring 34 has claws in the form of hooks 90 projecting radially at one end, forming forks 92 that are open on one side in the circumferential direction. Mushroom-shaped holders 94, which can be formed screws, for example, are provided on the valve body 10, either in one piece or via separate parts.

[0051] Here, too, the actuator 24 with the attached fastening unit is placed on the valve body 10, then the clamping ring 34 is rotated so that the holders 94 penetrate the forks 92 with their mushroom heads. The fastening unit is then further axially preloaded via the tensioning unit 32 in order to clamp the diaphragm 20 at the circumference.

[0052] In this embodiment, the membrane 20 is also visible on the circumference.

[0053] It should be emphasized that the various valve bodies 10 and bayonet closures 30 can of course also be combined with each other as desired.

Claims

[1] Diaphragm valve, comprising at least one valve body (10) having at least one inlet (12), at least one outlet (14), at least one flow channel (16) and at least one shut-off web (18) which divides the flow channel (16) into channel sections, a diaphragm (20) which rests on a circumferential sealing seat (22) of the valve body (10), a drive (24) with a drive housing, wherein the drive (24) is coupled to the diaphragm (20) in order to press the diaphragm (20) against the shut-off web (18) to close the valve, and a fastening unit for releasably locking the drive (24) on the valve body (10), wherein the fastening unit has a bayonet lock (30) and an additional, central tensioning unit (32), wherein an axial tensioning force is generated by the tensioning unit (32), characterized by , that the drive housing is designed in several parts and has an attachment housing part (28) on which the tensioning unit (32) is supported, wherein the attachment housing part (28) and the bayonet closure (30) are coupled to one another in a rotationally fixed manner via an axial guide (44, 46). [2] Diaphragm valve according to claim 1, characterized by that the tensioning unit (32) is a union nut (62). [3] Diaphragm valve according to claim 1 or 2, characterized by that the bayonet closure (30) has a clamping ring (34) with protruding claws which engage behind the valve-side projections. [4] Diaphragm valve according to claim 3, characterized by that the projecting claws are wing clamping claws (36) which axially engage around a radial flange section (38) on the valve body (10), which forms the valve-side extensions. [5] Diaphragm valve according to claim 1 or 2, characterized bythat the bayonet closure has a clamping ring (34) with radially projecting hooks (90) which engage the mushroom-shaped holders (94) on the valve seat side. [6] Diaphragm valve according to one of claims 3 to 5, characterized by that the tensioning unit (32) engages the clamping ring (34) and can move it in the axial direction. [7] Diaphragm valve according to one of the preceding claims, characterized by that the tensioning unit (32) has a support surface (67) with which it is axially supported on the drive housing in order to press the drive housing axially in the direction of the diaphragm (20). [8] Diaphragm valve according to one of the preceding claims, characterized by that the fastening unit and the drive housing are designed in such a way that the membrane (20) can be seen circumferentially from the side. [9] Diaphragm valve according to one of the preceding claims, characterized bythat the top housing part (28) presses the membrane (20) against the sealing seat (22) with a circumferential edge (48). [10] Diaphragm valve according to claims 7 and 9, characterized by that the support surface (67) rests against a shoulder (66) of the attachment housing part (28). [11] Diaphragm valve according to one of the preceding claims, characterized by that the top housing part (28) is bell-shaped and accommodates in its hollow interior the fastening of a lifting spindle (72) with the membrane (20). [12] Diaphragm valve according to claim 11, characterized by that the attachment housing part (28) has a central, axially extending sleeve extension (70) which projects into the interior of the drive housing and forms a guide for a lifting spindle (72). [13] Diaphragm valve according to one of the preceding claims, characterized bythat a main housing (26) of the drive is axially adjacent to the attachment housing part (28) and is connected to it, in particular is rotatably connected. [14] Diaphragm valve according to one of the preceding claims, characterized by that the membrane (20) is coupled to the attachment housing part (28) in a rotationally fixed manner via a positive connection.

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