Valve assembly for a pneumatic actuator and pneumatic drive device

Abstract

The invention relates to a valve device (V) comprising - a first connection (2) for connecting the drive, - two fluid paths (12, 13) each with an adjustable throttle check valve (5, 7) and a check function that blocks in the direction away from the first port (2), - a 3 / 2-way valve (4) via which the first port (2) is fluidly connected to the first fluid path (12) or to the second fluid path (13), - a second connection (3), and - a connecting fluid path (14) between the second connection (3) on the one hand and the fluid paths (12, 13) on the other. According to the invention, it is provided that - in the connecting fluid path (14) a releasable check valve (11) with a releasable check function that blocks in the direction of the second port (3) is arranged, and - a venting fluid path (6) is present, which branches off from the connecting fluid path (14) between the fluid paths (12, 13) on the one hand and the unlockable check valve (11) on the other hand and opens into a third port (17), and in which a 2 / 2-way valve (10) is arranged, which blocks or opens the venting fluid path (6).

Description

[0001] The invention relates to a valve device for a pneumatic drive according to the features of the preamble of claim 1 and a pneumatic drive device.

[0002] As described in DE 10 2016 008 440 A1, a valve assembly and a pneumatic actuator are known from the prior art. The valve assembly for the pneumatic actuator comprises a port through which the valve assembly can be fluidically connected to the pneumatic actuator, a first fluid path in which a throttle check valve is arranged with a check function that blocks in the direction away from the port, a second fluid path in which a first flow control device is arranged, and a valve element that is adjustable between two operating positions, wherein the port is fluidly connected to the first fluid path in the first operating position and to the second fluid path in the second operating position. It is provided that the second fluid path has a first bypass fluid path which is configured to fluidically bypass the first flow control device.A first check valve is arranged in the first bypass fluid path.

[0003] The invention is based on the objective of providing a valve device for a pneumatic drive that is improved compared to the prior art, and a pneumatic drive device that is improved compared to the prior art.

[0004] The problem is solved according to the invention by a valve device for a pneumatic drive with the features of claim 1 and a pneumatic drive device with the features of claim 9.

[0005] Advantageous embodiments of the invention are the subject of the dependent claims.

[0006] A valve assembly for a pneumatic actuator, also known as a valve block, multi-function block or multi-function valve block, has the following features: - a first connection via which the valve assembly can be fluidly connected to the pneumatic actuator, - a first fluid path in which an adjustable first throttle check valve is arranged, which has a check function that blocks in the direction away from the first port, - a second fluid path in which an adjustable second throttle check valve is arranged, which has a check function that blocks in the direction away from the first port, - a 3 / 2-way valve, wherein in a first operating position of the 3 / 2-way valve the first port is fluid-connected to the first fluid path and in a second operating position of the 3 / 2-way valve the first port is fluid-connected to the second fluid path, - a second connection via which the valve assembly can be fluid-connected, for example, to an upstream additional valve body and / or valve block and / or to a valve manifold and / or to a compressed air supply, in particular a working compressed air supply, and - a connecting fluid path between the second port on the one hand and the first fluid path and the second fluid path on the other.

[0007] Each adjustable throttle check valve has, in particular, an adjustable throttle and a check valve. Specifically, the check valve has a non-return function that blocks flow in the direction away from the first port.

[0008] According to the invention, a releasable check valve is arranged in the connecting fluid path, which has a releasable check function that blocks in the direction of the second port. That is, the check valve normally blocks in the direction of the second port, but can be unlocked so that it no longer blocks in the direction of the second port. The releasable check valve enables, for example, a venting function of a connected piston chamber of the pneumatic actuator.

[0009] According to the invention, the valve assembly has a venting fluid path that branches off from the connecting fluid path between the first and second fluid paths on the one hand and the unlockable check valve on the other, and opens into a third port. A 2 / 2-way valve is arranged in the venting fluid path, which closes the venting fluid path in a first operating position and opens it in a second operating position. The 2 / 2-way valve particularly enables the confinement of compressed air for drive blocking purposes.

[0010] In one embodiment, the adjustable first throttle check valve is provided for setting an automatic speed of the pneumatic drive. For example, it is possible to optionally set a maximum achievable automatic speed or to adapt the automatic speed to the prevailing conditions by reducing the maximum available compressed air flow.

[0011] In one embodiment, the adjustable second throttle check valve is provided for setting a reduced speed of the pneumatic drive compared to the automatic speed. This reduced speed, for example to 33 mm / second, particularly in accordance with VDMA 66416, is intended, for instance, for applications in a setup operation for moving individual pneumatic axes with the safety door open, for example, in connection with adjustment work, repairs, and other processes. The adjustable second throttle check valve has, for example, a tamper protection feature, particularly to prevent manipulation that could lead to a higher speed.

[0012] The 3 / 2-way valve thus advantageously allows either the automatic speed or the reduced speed of the pneumatic drive to be selected.

[0013] In one embodiment, the 3 / 2-way valve is fluid-connected to a first control air channel for its actuation, which opens into a fourth port. The 3 / 2-way valve can be controlled, for example, by a programmable logic controller (PLC). For example, the 3 / 2-way valve has a return spring and can be actuated, in particular by a supply of compressed air, especially control compressed air, via the first control air channel, against the spring force of the return spring into one functional position, for example, the first functional position, and returned to the other functional position, for example, the second functional position, by means of the return spring, especially after the supply of compressed air, especially control compressed air, via the first control air channel is switched off.

[0014] In one embodiment, a fifth connection for connecting a pressure sensor, a pressure switch and / or a manometer is fluid-connected to the first control air channel.

[0015] In one embodiment, the unlockable check valve is fluid-connected to a second control air channel for its actuation, which terminates in a sixth port. For example, the unlockable check valve can be controlled by a programmable logic controller (PLC), in particular unlocked and / or locked. For example, the unlockable check valve can be unlocked by supplying compressed air, in particular control compressed air, via the second control air channel and locked again by switching off this compressed air supply, in particular control compressed air.

[0016] In one embodiment, the 2 / 2-way valve is designed for manual operation. For example, the 2 / 2-way valve has a return spring and can be manually actuated against the spring force of the return spring to one functional position, for example, the second functional position, and returned to the other functional position, for example, the first functional position, by means of the return spring.

[0017] The valve assembly includes, in particular, a valve body. The components mentioned above are, in particular, arranged and / or formed within and / or on the valve body. Specifically, the connections mentioned above are, in particular, arranged or formed on the valve body.

[0018] A pneumatic drive device according to the invention comprises a pneumatic drive and a valve assembly. The valve assembly is fluidly connected to the pneumatic drive via the first connection.

[0019] The pneumatic drive is, for example, a pneumatic cylinder.

[0020] The described solution, in particular the described valve assembly, enables two speeds of the pneumatic actuator, a venting function, and a compressed air containment function. This solution specifically avoids the risk of unintentional venting, which could lead to a hazardous situation. Compared to other solutions, the described solution thus increases workplace safety while advantageously maintaining the same costs, and advantageously ensures compatibility with other solutions and / or the pneumatic actuator. This means that, in particular, no modifications to the pneumatic actuator are required.

[0021] The described design of the valve assembly ensures that even in the event of manual misuse of the 2 / 2-way valve and / or other technical errors, the reduced speed of the pneumatic drive is maintained when the 3 / 2-way valve is in the second operating position, in which the first port is fluid-connected to the second fluid path, in which the adjustable second throttle check valve is located for setting the reduced speed of the pneumatic drive.This is achieved by ensuring that there is no branching channel between the pneumatic actuator, which is fluid-connected to the first port, and the adjustable second throttle check valve for adjusting the reduced speed of the pneumatic actuator, the output of which can be released into an external environment by the manually operated 2 / 2-way valve, which may have various possible sources of error.

[0022] In the described solution, there is therefore no other path for air from the pneumatic actuator than the forced path through one of the two adjustable throttle check valves. There is no possibility for the air from the pneumatic actuator to escape at full force via a preceding branch channel, as no such branch channel exists.

[0023] This is ensured by the fact that the venting fluid path, in which the 2 / 2-way valve is arranged, branches off from the connecting fluid path between the first fluid path and the second fluid path on the one hand and the unlockable check valve on the other.

[0024] For example, a sensor-based, and in particular continuous, position monitoring of one or both operating positions of the 3 / 2-way valve is provided. This is the most reliable way to determine the actual switching state of the valve assembly with regard to the compressed air flow through the adjustable second throttle check valve for setting the reduced speed of the pneumatic actuator, or through the adjustable first throttle check valve for setting the automatic speed of the pneumatic actuator.

[0025] The described solution thus achieves greater occupational safety for personnel during setup. A fault in the 2 / 2-way valve does not affect the speed of the pneumatic actuator.

[0026] The described solution is no more complicated than other solutions, although it achieves higher security performance.

[0027] The described solution does not require more manufacturing effort than other solutions, since it advantageously uses the same control elements, which are, however, arranged differently.

[0028] The described solution is advantageously compatible with other solutions, so that these other solutions can be easily exchanged for the solution described here.

[0029] Exemplary embodiments of the invention are explained in more detail below with reference to drawings.

[0030] This shows: Fig. 1 schematically an embodiment of a valve device for a pneumatic actuator, and Fig. 2 schematically a significantly improved embodiment of a valve device for a pneumatic actuator.

[0031] Corresponding parts are marked with the same reference symbols in all figures.

[0032] The Fig. 1 and Fig. Figure 2 shows schematic representations of two embodiments of a valve device V for a pneumatic actuator. The one in Fig. 2 embodiment shown compared to the one in Fig. The embodiment shown in 1 is substantially improved, as will be explained below.

[0033] The pneumatic drive is, for example, a pneumatic cylinder.

[0034] A pneumatic drive device (not shown) comprises the pneumatic drive and the valve assembly V, in particular the embodiment according to Fig. 2. The valve assembly V is fluidly connected to the pneumatic actuator via a first connection 2.

[0035] The in Fig. The embodiment of the valve assembly V shown in Figure 1 comprises a valve body 1, a first port 2 through which the valve assembly V can be fluidly connected to or is fluidly connected to the pneumatic actuator, a second port 3, a 3 / 2-way valve 4, an adjustable first throttle check valve 5, an adjustable second throttle check valve 7, in particular with a tamper protection device, a 2 / 2-way valve 10, a releasable check valve 11, a first fluid path 12 in which the adjustable first throttle check valve 5 is arranged, which has a check valve function that blocks in the direction away from the first port 2, a second fluid path 13 in which the adjustable second throttle check valve 7 is arranged, which has a check valve function that blocks in the direction away from the first port 2, and a venting fluid path 6 that opens into a third port 17.wherein the 2 / 2-way valve 10 is arranged in the venting fluid path 6, which closes the venting fluid path 6 in a first operating position F1 and opens it in a second operating position F2, a first control air channel 20, which is fluid-connected to the 3 / 2-way valve 4 for its actuation and opens into a fourth port 18, wherein a fifth port 19 for connecting a pressure sensor, a pressure switch and / or a manometer is fluid-connected to the first control air channel 20, and a second control air channel 15, which is fluid-connected to the unlockable check valve 11 for its actuation and opens into a sixth port 16.

[0036] Furthermore, the following includes Fig. 1. The illustrated embodiment has a seventh connection 8 for connecting a pressure sensor, a pressure switch or a manometer.

[0037] The adjustable first throttle check valve 5 is intended for setting an automatic speed of the pneumatic drive and the adjustable second throttle check valve 7 is intended for setting a reduced speed of the pneumatic drive compared to the automatic speed.

[0038] In pneumatics, there are applications where several specific requirements arise for the pneumatic control elements that actuate the pneumatic cylinder and are arranged within the valve body 1. The following functions are required for the embodiments of the valve assembly V shown here: The automatic speed must be adjustable, allowing the user to choose between maintaining a maximum achievable speed or adapting the speed to the conditions by reducing the maximum available compressed air flow. This is achieved in the embodiment according to Fig. 1 implemented by the adjustable first throttle check valve 5.

[0039] The speed reduction for setup applications, for example to 33 mm / second according to VDMA 66416, for moving individual pneumatic axes with the safety door open, for example in connection with adjustment work or repairs, must be available. This is achieved in the embodiment according to Fig. 1 is implemented by the adjustable second throttle check valve 7.

[0040] There must be a way to select between the two speeds, i.e., the automatic speed or the reduced speed. This is achieved in the embodiment according to Fig. 1 implemented by the 3 / 2-way valve 4, controlled in particular by a programmable logic controller.

[0041] A manual venting function for the associated piston chamber of the pneumatic cylinder must be provided. This is achieved in the embodiment according to Fig. 1 implemented by the unlockable check valve 11.

[0042] It must be possible to trap compressed air for cylinder piston blocking purposes. This is achieved in the embodiment according to Fig. 1 implemented by the 2 / 2-way valve 10, in particular with manual actuation.

[0043] By the embodiment according to Fig. However, given the intended arrangement of the integrated control components, it cannot be ruled out that if the 3 / 2-way valve 4 is in a position where it is not actuated or one spring side of this 3 / 2-way valve 4 is active, the preselected reduced speed of 33 mm / second or less will not be implemented. The reason for this is the arrangement of the 2 / 2-way valve 10 for venting purposes. It cannot be ruled out that this mechanically actuated 2 / 2-way valve 10, which is therefore not subject to the switching logic of the programmable logic controller (PLC) and cannot be controlled or, if necessary, locked by software, might be actuated by a human at an inappropriate time, as humans are potentially fallible.

[0044] If this occurs during a phase in which a horizontal pneumatic cylinder may only be operated at a reduced speed in setup mode, the cylinder exhaust air, which should actually escape at a reduced speed via the 3 / 2-way valve 4 and subsequently only through the appropriately adjustable second throttle check valve 7 from the associated pneumatic cylinder piston chamber, escapes unthrottled into the atmosphere through this 2 / 2-way valve 10. The result would be a travel speed of the pneumatic cylinder that is several times higher than the actually required speed of 33 mm / second and, in all likelihood, also significantly higher than the automatic speed.

[0045] The unlockable check valve 11 will be activated during this phase; therefore, it does not prevent the scenario described above. Consequently, it would also not be able to prevent it if, from the perspective of the pneumatic cylinder, it were located upstream of the branch to the 2 / 2-way valve 10 for venting purposes, since, as already mentioned, it is activated in this situation and thus open to flow.

[0046] This creates an unnecessary risk to the occupational safety of individuals who may be located near individual pneumatic cylinder movements within separating safety barriers and who rely on the cylinder movements occurring at a reduced speed. This significantly hinders a person's ability to evade a pneumatic cylinder movement that is approaching at a significantly excessive speed, should the need arise.

[0047] This risk is further increased when vertical pneumatic cylinders are moved downwards, as gravity acts as an additional accelerator and force amplifier.

[0048] One indication of the importance of the reliability of driving at reduced speed is the existence of the tamper protection on the adjustable second throttle check valve 7, which is intended to prevent possible manipulation to increase the speed.

[0049] Furthermore, technical faults of the 2 / 2-way valve 10 can lead to leaks, for example a jamming or spring breakage, which means that the 2 / 2-way valve 10 does not close the outlet completely, even though no control compressed air is present.

[0050] At the in Fig. In the embodiment shown in Figure 1, the seventh port 8 allows the connection of a pressure sensor, pressure switch, or manometer. However, this does not provide a reliable indication in the associated compressed air channel as to whether the compressed air is currently flowing at automatic or reduced speed, or whether incipient leaks at the 2 / 2-way valve 10 are generating an individual deviation. A flow meter would be required for this, but it would be too expensive and far too large in this case. The use of this embodiment of the valve assembly V according to Fig. 1 therefore exhibits malfunction possibilities that can be switched / activated as soon as the 3 / 2-way valve 4 switches to the position for the reduced speed.

[0051] At the in Fig. In the significantly improved embodiment of valve device V shown in section 2, these risks and disadvantages of the one described in Fig. 1. The embodiment shown was avoided.

[0052] The in Fig. The embodiment of the valve assembly V shown in Figure 2 comprises the valve body 1, the first port 2, through which the valve assembly V can be fluidly connected to or is fluidly connected to the pneumatic actuator, the first fluid path 12, in which the adjustable first throttle check valve 5 is arranged, which has a check function that blocks in the direction away from the first port 2, the second fluid path 13, in which the adjustable second throttle check valve 7 is arranged, which has a check function that blocks in the direction away from the first port 2, and the 3 / 2-way valve 4.

[0053] In the embodiment according to Fig. In the first operating position F11 of the 3 / 2-way valve 4, the first port 2 is connected to the first fluid path 12, and in the second operating position F22 of the 3 / 2-way valve 4, the first port 2 is connected to the second fluid path 13. In the situation shown, the 3 / 2-way valve 4 is in the second operating position F22.

[0054] The valve assembly V also has the second connection 3, via which the valve assembly V can be fluidly connected or fluidly connected to, for example, an upstream further valve body and / or valve block and / or to a valve manifold and / or to a compressed air supply, in particular a working compressed air supply.

[0055] Furthermore, the valve device V in the embodiment according to Fig. 2 a connecting fluid path 14 between the second port 3 on the one hand and the first fluid path 12 and the second fluid path 13 on the other. The unlockable check valve 11 is, in this embodiment, according to Fig. 2 is arranged in this connecting fluid path 14 and has an unlockable backstop function that locks in the direction of the second terminal 3.

[0056] The valve assembly V further comprises the venting fluid path 6, which opens into the third port 17 and in which the 2 / 2-way valve 10 is arranged, which closes the venting fluid path 6 in the first operating position F1 and opens it in the second operating position F2. In the embodiment according to Fig. 2 The venting fluid path 6 branches off from the connecting fluid path 14 between the first fluid path 12 and the second fluid path 13 on the one hand and the unlockable check valve 11 on the other. The 2 / 2-way valve 10 allows, in particular, the confinement of compressed air for drive blockage purposes.

[0057] Even in the embodiment according to Fig. 2 The adjustable first throttle check valve 5 is provided for setting the automatic speed of the pneumatic actuator. For example, it is possible to optionally set the maximum achievable automatic speed or to adapt the automatic speed to the prevailing conditions by reducing the maximum available compressed air flow. For example, it has a corresponding marking, such as the letter A for automatic speed.

[0058] Even in the embodiment according to Fig. 2 The adjustable second throttle check valve 7 is provided for setting the reduced speed of the pneumatic drive compared to the automatic speed. This reduced speed, for example to 33 mm / second, particularly according to VDMA 66416, is intended, for example, for setup applications for moving individual pneumatic axes with the safety door open, for example in connection with adjustment work, repairs and other operations. It has a corresponding marking, for example by means of the letter R for reduced speed.

[0059] The adjustable second throttle check valve 7, for example, has a tamper-evident feature, particularly to prevent manipulation that could lead to a higher speed. For example, it has a corresponding marking, such as the letter M for tamper-evident or a corresponding symbol, such as a padlock symbol.

[0060] By means of the 3 / 2-way valve 4, it is therefore advantageously possible to select either the automatic speed or the reduced speed of the pneumatic drive.

[0061] In the embodiment according to Fig. In section 2, the 3 / 2-way valve 4 is fluid-connected to the first control air channel 20, which opens into the fourth port 18. The 3 / 2-way valve 4 can be controlled, for example, by a programmable logic controller (PLC). In the illustrated example, the 3 / 2-way valve 4 has a return spring 9 and can be moved into the first operating position F11 by means of an actuation, in particular by a supply of compressed air, especially control compressed air, via the first control air channel 20, against the spring force of the return spring 9, and returned to the second operating position F22 by means of the return spring 9, in particular after switching off the supply of compressed air, especially control compressed air, via the first control air channel 20.

[0062] In the embodiment according to Fig. 2 is the fifth connection 19 for connecting a pressure sensor, a pressure switch and / or a manometer to the first control air channel 20 fluid-connected.

[0063] In the embodiment according to Fig. 2. The unlockable check valve 11 is fluid-connected to the second control air channel 15, which opens into the sixth port 16, for its actuation. For example, the unlockable check valve 11 can be controlled by a programmable logic controller (PLC), in particular unlocked and / or locked. For example, the unlockable check valve 11 can be unlocked by a compressed air supply, in particular a control compressed air supply, via the second control air channel 15 and locked again by switching off this compressed air supply, in particular a control compressed air supply.

[0064] In the embodiment according to Fig. 2 The 2 / 2-way valve 10 is designed for manual operation. In the illustrated example, the 2 / 2-way valve 10 has a return spring 21 and can be manually actuated against the spring force of the return spring 21 to move it into the second operating position F2 and back to the first operating position F1 by means of the return spring 21.

[0065] The embodiment of the valve device V thus represents an improvement without the risks listed above for the embodiment according to Fig. 1. This is represented by the embodiment according to Fig. 2 the same range of functions covered.

[0066] Due to the compared to Fig. 1. The modified arrangement of the control components now ensures that even in the event of manual misuse of the 2 / 2-way valve 10 and / or other technical errors, compliance with the reduced speed of the pneumatic drive is maintained when the 3 / 2-way valve 4 is in the second operating position F22, in which the first port 2 is fluidly connected to the second fluid path 13, in which the adjustable second throttle check valve 7 is located for setting the reduced speed of the pneumatic drive.

[0067] This is achieved by eliminating a branch channel between the pneumatic actuator, which is fluid-connected to the first port 2, and the adjustable second throttle check valve 7 for adjusting the reduced speed of the pneumatic actuator. This branch channel's outlet to the external environment could be opened via the manually operated 2 / 2-way valve 10, which could have various potential sources of failure. Therefore, in the described solution, there is no other path for air from the pneumatic actuator than the forced path through one of the two adjustable throttle check valves 5 or 7.

[0068] There is no way for the air from the pneumatic actuator to escape at full force via a preceding branch channel, as no such branch channel exists. This is ensured by the fact that the venting fluid path 6, in which the 2 / 2-way valve 10 is located, branches off from the connecting fluid path 14 between the first fluid path 12 and the second fluid path 13 on the one hand, and the unlockable check valve 11 on the other.

[0069] For example, a sensor-based, in particular permanent, position monitoring of one of the two functional positions F11, F22 or both functional positions F11, F22 of the 3 / 2-way valve 4 is provided. This is the most reliable way to determine which switching state actually prevails in the valve assembly V with regard to the compressed air flow through the adjustable second throttle check valve 7 for setting the reduced speed of the pneumatic actuator or through the adjustable first throttle check valve 5 for setting the automatic speed of the pneumatic actuator.

[0070] By the embodiment of the valve device V according to Fig. 2. This results in increased occupational safety for personnel during setup. A fault in the 2 / 2-way valve 10 does not affect the speed of the pneumatic actuator.

[0071] The embodiment of the valve device V according to Fig. 2 is no more complicated than the embodiment of the valve device V according to Fig. 1, although a higher security performance is achieved.

[0072] The embodiment of the valve device V according to Fig. 2 does not require any higher manufacturing effort than the embodiment of the valve device V according to Fig. 1, since the same control elements are advantageously used, but arranged differently.

[0073] The embodiment of the valve device V according to Fig. 2 is advantageously compatible with the embodiment of the valve device V according to Fig. 1, so that the embodiment according to Fig. 1 in a simple way against the embodiment according to Fig. 2 is interchangeable.

Claims

[1] Valve assembly (V) for a pneumatic actuator, comprising - a first connection (2) via which the valve assembly (V) can be fluidly connected to the pneumatic actuator, - a first fluid path (12) in which an adjustable first throttle check valve (5) is arranged, which has a check function that blocks in the direction away from the first port (2), - a second fluid path (13) in which an adjustable second throttle check valve (7) is arranged, which has a check function that blocks in the direction away from the first port (2), - a 3 / 2-way valve (4) wherein in a first operating position (F11) of the 3 / 2-way valve (4) the first port (2) is fluid-connected to the first fluid path (12) and in a second operating position (F22) of the 3 / 2-way valve (4) the first port (2) is fluid-connected to the second fluid path (13), - a second connection (3), and - a connecting fluid path (14) between the second port (3) on the one hand and the first fluid path (12) and the second fluid path (13) on the other hand, characterized by , that - in the connecting fluid path (14) a releasable check valve (11) is arranged and has a releasable check function that blocks in the direction of the second port (3), and - a venting fluid path (6) is provided, which branches off from the connecting fluid path (14) between the first fluid path (12) and the second fluid path (13) on the one hand and the unlockable check valve (11) on the other hand and opens into a third port (17), wherein a 2 / 2-way valve (10) is arranged in the venting fluid path (6), which closes the venting fluid path (6) in a first operating position (F1) and opens it in a second operating position (F2). [2] Valve assembly (V) according to claim 1, characterized by, that the adjustable first throttle check valve (5) is provided for setting an automatic speed of the pneumatic drive and the adjustable second throttle check valve (7) is provided for setting a reduced speed of the pneumatic drive compared to the automatic speed. [3] Valve assembly (V) according to any one of the preceding claims, characterized by , that the adjustable second throttle check valve (7) has a tamper protection feature. [4] Valve assembly (V) according to any one of the preceding claims, characterized by , that the 3 / 2-way valve (4) is fluidly connected to a first control air channel (20) for its control, which leads into a fourth port (18). [5] Valve assembly (V) according to claim 4, characterized by, that a fifth connection (19) for connecting a pressure sensor, a pressure switch and / or a manometer is fluidly connected to the first control air channel (20). [6] Valve assembly (V) according to any one of the preceding claims, characterized by , that the unlockable check valve (11) is fluidly connected to a second control air channel (15) for its control, which leads into a sixth connection (16). [7] Valve assembly (V) according to any one of the preceding claims, characterized by , that the 2 / 2-way valve (10) is designed for manual operation. [8] Valve assembly (V) according to any one of the preceding claims, characterized by a valve body (1). [9] Pneumatic drive device comprising a pneumatic drive and a valve assembly (V) according to one of the preceding claims, which is fluidly connected to the pneumatic drive via the first connection (2). [10] Pneumatic drive device according to claim 9, characterized by , that the pneumatic drive is a pneumatic cylinder.

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