Pendulum valve with calibration device

Abstract

The pendulum valve (10) has a valve seat with a first sealing surface and a valve closing member (14) with a second sealing surface corresponding to the first sealing surface, the valve closing member being pivotally supported about a pivot axis (R) by a drive unit (19). The pendulum valve (10) has a calibration surface and a position sensor for detecting a distance between the position sensor and the calibration surface, the position sensor being arranged in a fixed positional relationship relative to the valve seat, the calibration surface being movably arranged and connected to the valve closing member (14) such that the position of the calibration surface and the distance between the position sensor and the calibration surface change during a pivoting movement of the valve closing member (14).

Description

[Technical field]

[0001] The present invention relates to a calibration device for compensating for bearing play in a pendulum valve and to a pendulum valve with a calibration function.

[0002] Generally, valves are provided in order to make it possible to regulate the throughflow of fluids in particular. The valves can allow the flow through the largest valve opening cross section or can completely block it. Furthermore, certain types of valves can control the amount of throughflow per unit of time, i.e. provide controllability of the fluid throughflow.

[0003] Vacuum valves constitute one particular valve type, which are known from the prior art in different embodiments for controlling the volumetric or mass flow rate and / or for substantially gas-tight closing of a flow passage extending through an opening molded in the valve casing, and are used in particular in vacuum chamber systems in the field of IC, semiconductor or substrate manufacturing, which must take place in a protected atmosphere and as far as possible without the presence of impurity particles.

[0004] Such a vacuum chamber system has, in particular, at least one evacuable vacuum chamber provided for receiving a semiconductor element or substrate to be processed or manufactured, the vacuum chamber having at least one vacuum chamber opening through which the semiconductor element or other substrate can be introduced into the vacuum chamber and removed from the vacuum chamber, as well as at least one vacuum pump for evacuating the vacuum chamber. For example, in manufacturing facilities for semiconductor wafers or liquid crystal substrates, highly sensitive semiconductor elements or liquid crystal elements are continuously passed through a number of vacuum process chambers in which the components located therein are processed by respective processing devices. During the processing process in the vacuum process chambers and also during the transfer from chamber to chamber, the highly sensitive semiconductor elements or substrates must always be located in a protective atmosphere, in particular in a vacuum environment.

[0005] For this purpose, on the one hand, peripheral valves are used to open and close the gas supply or gas exhaust, and on the other hand, transfer valves are used to open and close transfer openings in the vacuum chamber for introducing and removing the components.

[0006] Vacuum valves passed by semiconductor components are called vacuum transfer valves on the basis of the above-mentioned fields of use and the associated dimensional design, square valves on the basis of their mostly rectangular opening cross sections, and gate valves, square gate or transfer gate valves on the basis of their usual functional form.

[0007] Peripheral valves are used in particular for open-loop or closed-loop control of the gas flow between a vacuum chamber and a vacuum pump or another vacuum chamber. Peripheral valves are located, for example, inside the conduit system between a vacuum process chamber or transfer chamber and a vacuum pump, atmosphere or another vacuum process chamber. The opening cross section of such types of valves, also called pump valves, is usually smaller than the opening cross section of a vacuum transfer valve. Peripheral valves are also called control valves, since, depending on the field of use, they are used not only for the complete opening and closing of the opening, but also for the open-loop or closed-loop control of the flow by continuously adjusting the opening cross section between a completely open position and a gas-tight closed position. Peripheral valves that can be used for the open-loop or closed-loop control of the gas flow are pendulum valves.

[0008] In a typical pendulum valve, as known, for example, from US Pat. No. 6,089,537 (Olmsted), in a first step, a normally circular valve plate is rotated and pivoted over an also normally circular opening from a position that releases the opening to an intermediate position that covers the opening. In the case of a gate valve, as described, for example, in US Pat. No. 6,416,037 (Geiser) or US Pat. No. 6,056,266 (Blecha), the valve plate, and also the opening, are often rectangular in shape, and in this first step, it is linearly slid from a position that releases the opening to an intermediate position that covers the opening. In this intermediate position, the valve plate of the pendulum valve or gate valve is located in a spaced-apart opposite position to a valve seat surrounding the opening. In a second step, the distance between the valve plate and the valve seat is reduced so that the valve plate and the valve seat are pressed uniformly against each other, and the opening is closed substantially gas-tight. This second movement is preferably performed in a direction substantially perpendicular to the valve seat.

[0009] The sealing may be achieved, for example, via a sealing ring arranged on the closing side of the valve plate, which presses against a valve seat surrounding the opening, or via a sealing ring provided on the valve seat against which the closing side of the valve plate presses. Since the movement of the valve plate in the second step is performed substantially linearly and perpendicular to the valve seat, the closing process performed in the second step causes the sealing ring between the valve plate and the valve seat to hardly yield to shear forces that would destroy the sealing ring.

[0010] Different sealing devices are known from the prior art, for example from US Patent No. 6,629,682 (Duelli). Suitable materials for sealing rings and sealing elements in vacuum valves are, for example, fluororubbers, also called FKM, in particular the fluoroelastomers known under the trade name "Viton", and perfluororubbers, abbreviated FFKM.

[0011] Furthermore, various drive systems are known from the prior art for obtaining such a combination of a rotational movement of the valve plate parallel to the opening in pendulum valves and a translational movement in gate valves, with a substantially translational movement perpendicular to the opening, for example from U.S. Pat. No. 6,089,537 (Olmsted) for pendulum valves and from U.S. Pat. No. 6,416,037 (Geiser) for gate valves.

[0012] The pressing of the valve plate against the valve seat must be performed in such a way that the required tightness is guaranteed inside the entire pressure area, particularly for vacuum applications, and damage to the sealing medium, in particular the sealing material or the sealing ring (e.g. O-ring), due to excessive pressure load is avoided. To ensure this, in known valves, a pressing pressure regulation of the valve plate is performed, which is controlled in relation to the pressure difference existing between the two valve plate sides. However, a uniform force distribution along the entire circumference of the sealing ring cannot always be guaranteed, especially in the case of large pressure fluctuations or changes from negative pressure to positive pressure or vice versa. However, the aim is generally to decouple the sealing ring from the supporting forces that arise due to the pressure acting on the valve.

[0013] The valves described above are used, among other things, in the manufacture of very sensitive semiconductor components in vacuum chambers, so that a suitable sealing effect must also be reliably guaranteed for such vacuum chambers. For this purpose, the overall condition of the valve, or in particular the condition of the sealing material or the condition of the sealing surfaces that come into contact with the sealing material when pressed, is particularly important. During the course of the operating period of a vacuum valve, changes in the valve components can typically occur due to wear of the sealing material or sealing surfaces, as well as due to structural changes of the valve components, for example the drive unit or the valve rod, due to environmental influences (temperature, humidity, impacts, etc.).

[0014] Disturbances may also result from the support of the valve closing member or the drive shaft. This may be due to the fact that the pendulum valve is assembled and calibrated in a certain position at the factory, but the installation position of the valve at the customer's site differs from the assembled position. Due to the certain bearing play, such a change in position may lead to a displacement of the valve closing member relative to the valve seat, especially when reaching the closed position.

[0015] SUMMARY OF THE PRESENT EMBODIMENT The problem underlying the present invention is therefore to provide an improved pendulum valve, in particular a vacuum pendulum valve, which reduces or avoids the above-mentioned disadvantages.

[0016] It is a further object of the present invention to provide an improved pendulum valve that provides reliable sealing functionality in an installed state.

[0017] This object is achieved by means of the features set forth in the characterizing part of the independent claims.Features which further develop the invention alternatively or in advantageous ways are set forth in the dependent claims.

[0018] The idea behind the invention is to provide a vacuum pendulum valve with a sensor for detecting a distance, by means of which a distance to a surface connected to the valve closing member can be detected, which distance can be dependent on the pivotably adjustable opening position of the closing member as well as on the spatial orientation of the valve, for example due to gravity acting on the valve closing member. By means of the distance measurement, a position calibration of the valve closing member can be carried out and any deviations from the target position that may occur can be compensated for.

[0019] The invention thus relates to a pendulum valve, in particular a vacuum pendulum valve for controlling a volume or mass flow rate and / or for opening and closing a valve opening. The pendulum valve has a valve seat defining a valve opening defining an opening axis and having a first sealing surface surrounding the valve opening. The valve seat can, for example, be molded into the valve casing. Furthermore, a valve closing member, in particular a valve plate, for controlling the volume or mass flow rate and / or for tightly closing the valve opening is provided, having a second sealing surface corresponding to the first sealing surface. The valve closing member is supported so as to be pivotable about a pivot axis.

[0020] The pendulum valve also has a drive unit connected to the valve closing member, which drive unit is configured to provide a pivoting movement of the valve closing member about a pivot axis such that the valve closing member is adjustable from an open position, in which it at least partially releases the valve opening, to a closed position, in which it is located in or above the valve opening and (completely) covers the opening cross-section of the valve opening, and back.

[0021] In the closed position, in particular, intimate contact between the first and second sealing surfaces can be created by a sealing material (e.g., a sealing ring comprising a fluoropolymer) present therebetween, thereby allowing the valve opening to be hermetically closed.

[0022] The pendulum valve has a calibration surface and a position sensor for detecting a distance between the position sensor and the calibration surface.

[0023] The position sensor is disposed in a fixed position relative to the valve seat, and the calibration surface is movably connected to the valve closure member such that the position of the calibration surface and the distance between the position sensor and the calibration surface change during pivoting movement of the valve closure member.

[0024] The position sensor can in one embodiment be configured as an optical distance sensor, as an inductive distance detection sensor or as an acoustic distance sensor.

[0025] Such a device therefore makes it possible to detect a distance between the sensor and the calibration surface which depends at least on the position of the valve closing member.

[0026] In one embodiment, the pendulum valve may have a coupling which connects or couples the valve closure member to the drive unit, and the calibration surface is provided by the coupling or the valve closure member.

[0027] The coupling may in particular have or be formed as a shaft and / or a gearing, and the calibration surface may be provided as a stopper coupled to or molded with the coupling.

[0028] The calibration surface can be arranged, for example, on the motor shaft or on a movable element coupled to the shaft, which is moved accordingly when the valve closing member is pivoted. The position of the valve closing member can thus be inferred by measuring the distance to the calibration surface. In particular, the angular position of the closing member about the pivot axis can be detected, i.e. the position of the closing member between the open position and the closed position. In other words, based on the detected distance between the position sensor and the calibration surface, the current position of the valve closing member relative to the valve seat can be calculated.

[0029] According to one configuration, the pendulum valve may have a control and processing unit with at least a control function and a calibration function, the control function being configured to control the pivoting movement of the valve closure member, for example to control the opening and closing of the valve and all pressure control settings between the open and closed positions.

[0030] The calibration function is configured to detect, when performing the calibration, a distance between the calibration surface and the position sensor as a calibration value, and compare the calibration value with a reference value to generate corresponding calibration information.

[0031] The reference value may in particular be provided as a reference distance between the calibration surface and the position sensor.

[0032] This reference distance may further in particular provide or correspond to a distance between the calibration surface and the position sensor in a target closed position of the valve closing member, in which the projections of the first and second sealing surfaces onto a plane parallel to the first and / or second sealing surfaces at least partially, in particular completely, overlap.

[0033] In the target closed position, the first sealing surface and the second sealing surface may be concentrically disposed.

[0034] In the above embodiment, the valve closing member can be moved, for example, by a control and processing unit, to a target closing position. In this case, it can be ensured from the outside (not from the functionality of the valve itself, but for example by a user) that there is a correspondingly correct positioning of the valve closing member or the second sealing surface relative to the valve seat or the first sealing surface. In this target closing position, measurements can be made by a position sensor in this case, and the distance values ​​detected can be stored as reference values. This step is preferably carried out during the manufacture of the valve.

[0035] In one embodiment, within the scope of the calibration function, a calibration value is determined in the closed position of the valve closing member. The closed position (also called actual closed position) in this case corresponds to the position or state that the closing element would assume if it were moved to the closed position solely by the control and processing unit. In this case, no further (external) check of this position is performed, and it is typically assumed that the desired closed position has thus been reached. The calibration value can accordingly provide or may correspond to the distance between the calibration surface and the position sensor in this controlled reached closed position of the valve closing member.

[0036] The determination of the calibration value can preferably be carried out at the production factory after incorporation of the pendulum valve (eg at a production line for semiconductors) or during assembly there.

[0037] In one embodiment, the calibration information may in particular correspond to the deviation of the actual closed position from the target closed position. Alternatively or additionally, the calibration information may be the difference between the distance detected at the target closed position and the distance detected at the actual closed position.

[0038] According to one embodiment, within the scope of the calibration function the control function may be adapted depending on the calibration information.

[0039] In particular, the calibration information may indicate a deviation of the calibration value from a reference value, and the control function may be adapted so that, upon pivoting of the valve closure member towards the closed position, the closed position reached thereby (actual closed position) corresponds to the target closed position.

[0040] According to the invention, this allows a calibration of the pendulum valve to be carried out by first carrying out a reference measurement of the distance between the calibration surface and the sensor and then carrying out a calibration measurement of the distance between the calibration surface and the sensor, so that a control adaptation can be carried out based on a comparison of the reference measurement with the calibration measurement.

[0041] The adaptation of the control function can be performed in such a way that the control function can move the closing element to the closed position such that, as a result of the adaptation, deviations of the distance detectable in the actual closed position from the distance detectable in the target closed position are reduced or avoided (eliminated). For this purpose, typically control parameters of the control function such as the pivoting duration, the pivoting speed, the pivoting angle, the motor current, etc. can be adapted.

[0042] In one embodiment, the pendulum valve may have a separation device for separating the process atmosphere region from the outer atmosphere region, which particularly relates to the configuration of the pendulum valve as a vacuum pendulum valve.

[0043] By process atmosphere area, in particular, it is meant an area that can be defined by a process chamber (vacuum chamber). In this area, a process atmosphere, in particular a vacuum, can be generated for processing a substrate (e.g., a semiconductor). The components provided for this area must be sufficient, for example, in terms of material resistance and high requirements. Correspondingly, by outer atmosphere area, in particular, it is meant an area in which normal atmospheric conditions, for example room air, are present.

[0044] The drive unit can in this case be at least partially, in particular completely, assigned to the outer atmospheric region, and the valve-closing member can in particular be assigned to the process atmospheric region.

[0045] The isolating device of the valve may, for example, be formed by a bellows, which may, for example, be provided inside the valve casing or the drive unit.

[0046] A valve known from the prior art, for example as described in US Pat. No. 6,772,989, has a valve body with two connection ports, a valve seat arranged in a flow passage connecting the two connection ports in a flow space, and an opening facing the valve seat. A piston of a pneumatic cylinder system is arranged in a valve cover closing the opening, which piston drives a valve plate via a valve stem, which opens and closes the valve seat. The valve cover is gas-tightly attached to the opening by a bellows plate. The ends of a bellows surrounding the valve stem are gas-tightly attached to the inner edge surface of the bellows plate and to the valve plate. On its surface facing the valve seat, the valve plate has a ring-shaped retaining groove, in which a sealing ring is arranged.

[0047] In the case of a transfer to a pendulum valve according to the invention, the valve stem can be embodied by a coupling (eg a gear or a shaft).

[0048] The valve casing of a pendulum valve is made, for example, from aluminum or stainless steel or is lined on the inside with aluminum or another suitable material, while the valve plate and the bellows are usually made of steel. A bellows, which can expand and contract in the direction of the longitudinal axis in the area of ​​the adjustment distance of the plate, seals the flow space airtight from the valve stem and the actuator. In particular, two types of bellows are used: diaphragm bellows and gangway bellows. Gangway bellows have the advantage over diaphragm bellows in that they have no welded seams and are easier to clean, but they have a relatively small maximum stroke.

[0049] The invention further relates to a method for calibrating the pendulum valve described above, said method comprising at least the following steps: detecting a distance between the calibration surface and the position sensor as a calibration value; comparing the calibration value with a reference value, the reference value providing a reference distance (target distance) between the calibration surface and the position sensor; providing calibration information indicative of deviation of the calibration value from a reference value; and adapting the control of the pivoting movement of the valve closing member based on the calibration information so that during the pivoting movement of the valve closing member to the closed position, the closed position reached thereby corresponds to the target closed position. It has.

[0050] The invention further relates to a computer program product comprising a program code stored on a machine-readable carrier, in particular in a control and processing unit of the pendulum valve as described above, or a computer data signal embodied by an electromagnetic wave for implementing or controlling the steps of the method as described above. The computer program product may comprise an algorithm configured for this purpose.

[0051] The valve according to the invention will now be described in more detail, purely by way of example, with reference to an embodiment shown diagrammatically in the drawings, in which identical elements are provided with the same reference numerals, and in which the described embodiments are generally not drawn to scale and should not be understood as limiting. [Brief description of the drawings]

[0052] [Figure 1a] 1 shows an embodiment of a vacuum pendulum valve according to the present invention; [Figure 1b] 1 shows an embodiment of a vacuum pendulum valve according to the present invention; [Figure 2a] FIG. 2 is a cross-sectional view of an embodiment of a pendulum valve according to the present invention in a closed position. [Figure 2b] 2 is an enlarged view of a portion of a pendulum valve in the region of the drive unit, showing an embodiment of the pendulum valve according to the invention in the closed position; FIG. [Figure 3a] FIG. 2 is a cross-sectional view of an embodiment of a pendulum valve according to the present invention in an open position. [Figure 3b] 2 is an enlarged view of a portion of the pendulum valve in the region of the drive unit, showing an embodiment of the pendulum valve according to the invention in the open position; FIG. [Figure 4] 3 is a cross-sectional view in the edge region of the valve closing member of a valve according to the invention;

[0053] 1a and 1b show an embodiment of a vacuum pendulum valve 10 according to the invention. The valve 10 is designed for substantially gas-tight blocking of a flow passage, in particular for controlling the mass flow rate. The valve 10 has a valve casing 11 with an opening 12, which in this case has, for example, a circular cross section. The opening 12 is surrounded by a valve seat, which has a first sealing surface 13 which faces axially in the closed position towards a valve closing member 14 (valve plate), extends transversely to the opening axis A and has the shape of a ring, which first sealing surface is molded into the valve casing 11 in the illustrated example.

[0054] The valve closing member 14 is pivotable about a rotation axis R and is positionably adjustable substantially parallel to the opening axis A. In the closed position S of the valve plate 14 (valve closing member) (FIG. 1a), the opening 12 is covered by the valve plate 14 having a second sealing surface comprising a sealing material. The open position of the valve 10 is shown in FIG. 1b. In this case, the valve closing member 14 is pivoted about the pivot axis such that the opening 12 is fully open and the valve closing member 14 is located in the valve casing 11.

[0055] The valve closing member 14 is connected to a drive unit 19 (e.g. a motor) via an arm (not shown) arranged laterally of the closing member and extending perpendicular to the opening axis, which in the closed position of the valve plate 14 (FIG. 1a) is located outside the opening cross section of the opening 12 projected geometrically along the opening axis A.

[0056] The drive 19 is configured, by means of a corresponding gearing, so that the valve plate 14 can be pivoted between an open position (FIG. 1b) and a closed position (FIG. 1a) by a lateral movement x by the drive 19 transverse to the opening axis A - as is usual for pendulum valves - and in the form of a pivoting movement about a pivot axis R substantially parallel to the cross section of the opening 12 and perpendicular to the opening axis A.

[0057] The closed position may be understood as a state of the valve closing member 14 in which it at least covers the opening 12. In the closed position, the valve closing member 14 may be located in a relatively contact-free position with respect to the valve seat (intermediate position; no complete sealing of the opening by contact of both the first and the second sealing surface with the sealing material is provided). However, in the closed position, a gas-tight closing of the opening 12 (sealing position) may also be provided. In this case, the sealing material on the side of the valve closing member 14 is in contact with the first sealing surface 13. The valve closing member 14 is linearly slidable by the drive 19 for this purpose in accordance with a longitudinal movement y made along the opening axis A.

[0058] As already mentioned, in the open position, the valve plate 14 is located in a rest section arranged laterally adjacent the opening 12, so that the opening 12 and the flow path are free. In the intermediate position, the valve plate 14 is located at a distance above the first opening 12 and covers the opening cross section of the opening 12. In the sealed position, there is gas-tight contact (by means of the sealing material) between the valve closing member 14 and the sealing surface 13 of the valve seat, so that the opening 12 is gas-tightly closed and the flow path is blocked.

[0059] To enable automated and controlled opening and closing of the valve, the valve can have an electronic control and processing unit 18, which is configured so that the valve plate 14 can be correspondingly adjusted in position for tightly closing a process volume or for closed-loop control of the internal pressure of this volume and is thus connected to a drive 19. Such a control and processing unit 18 together with the valve, the process chamber and, for example, peripheral units (for example, gas inlet units) can form the core of a vacuum working apparatus, as is used, for example, in semiconductor manufacturing.

[0060] The position of the valve plate 14 can be variably adjusted based on the control value and the transmitted control signal. As an input signal, for example, information about the current pressure state in the process volume connected to the valve can be received. In addition, the closed-loop control device can be provided with further input values, for example the mass flow rate into the volume. Based on these values ​​and on a predefined target pressure to be set or reached for the volume, a closed-loop controlled adjustment of the valve can be performed over the time of a control cycle, so that the mass flow rate leaving the volume can be closed-loop controlled over time by the valve. For this purpose, a vacuum pump is typically provided behind the valve, i.e. the valve is arranged between the process chamber and the pump. The desired pressure progression can thus be controlled.

[0061] By adjusting the position of the valve closing element 14, the respective opening cross section for the valve opening 12 and thus the possible amount of gas that can be evacuated from the process volume per unit of time can be adjusted. For this purpose, the valve closing element 14 can have a shape different from a circular shape, in particular in order to obtain a medium flow that is as laminar as possible.

[0062] To adjust the opening cross section, the valve plate 14 can be adjusted by the control and processing unit 18 from the open position to the intermediate position via a lateral movement x by the drive 19 and from the intermediate position to the sealing position via a longitudinal movement y by the drive 19. For complete opening of the flow passage, the valve plate 14 can be adjusted by the open-loop control device from the sealing position to the intermediate position via a longitudinal movement y and from there from the intermediate position to the open position via a lateral movement x.

[0063] In this embodiment, the drive 19 is configured as an electric motor, and the gearing is switchable so that the drive of the drive 19 produces either a lateral movement x or a longitudinal movement y. The drive 19 and the gearing are electronically controlled by a closed-loop control device. Gearings of this type, in particular with gated shifting devices, are known from the prior art. Furthermore, it is also possible to use multiple drives for producing the lateral movement x and the longitudinal movement y, in which case an open-loop control device takes over the control of the drives. In such an embodiment, the multiple drives may be understood as part of the drive unit.

[0064] A precise closed-loop control or regulation of the throughflow with the described pendulum valve is possible not only by a pivotal movement of the valve plate 14 via a lateral movement x between an open position and an intermediate position, but also, inter alia, by a linear movement of the valve plate 14 along the opening axis A via a longitudinal movement y between an intermediate position and a sealed position. The described pendulum valve can be used for precise closed-loop control tasks.

[0065] Both the valve plate 14 and the valve seat have sealing surfaces - a first sealing surface and a second sealing surface, respectively. The second sealing surface of the valve closing member further has a sealing element. This sealing element may be vulcanized and fixed, for example as a polymer, on the second sealing surface by vulcanization. Alternatively, the sealing element may be formed, for example, as an O-ring in a groove of the valve closing member. A sealing material may be bonded to the valve closing member, which may then embody the sealing element. In an alternative embodiment, the sealing element may be arranged on the side of the valve seat, in particular on the first sealing surface 13. Combinations of these configurations are also conceivable.

[0066] The control and processing unit 18 may, for example, be constructed in an integrated manner with the vacuum valve, i.e. the control and processing unit is provided by and together with the valve, or alternatively the control and processing unit may be provided physically separated from the valve 10 and may, for example, be communicatively connected wirelessly to the drive unit 19 and / or the position sensor 21.

[0067] The pendulum valve 10 further comprises a position sensor 21, which is designed to detect the distance between the position sensor 21 and a calibration surface 22. The position sensor 21 is arranged in a fixed position relative to the valve seat or in the valve housing 11. The calibration surface 22 is connected to the valve closing member 14 and is arranged movably such that during a pivoting movement of the valve closing member 14 the position of the calibration surface 22 and the distance between the position sensor 21 and the calibration surface 22 change accordingly.

[0068] The position sensor 21 may be configured as an inductive or optical sensor for detecting the distance to a target (in this case: the calibration surface 22).

[0069] Figure 2a shows the pendulum valve 10 of Figure 1a in a cross-sectional view (cut in a plane perpendicular to the opening axis A) in the closed position. Figure 2b shows a part of the valve 10 of Figure 2a in the region of the drive unit 19.

[0070] The position sensor 21 is in the illustrated example fixedly connected to part of the drive unit 19, for example to the casing. Furthermore, electrical connections 23 of the sensor, in particular a cable, for the energy supply of the sensor 21 and / or for the transmission of measurement signals from the sensor 21 to the control and processing unit 18 are shown. In alternative embodiments, the connections 23 can be omitted and, for example, an energy supply (e.g. a battery or rechargeable battery) and a wireless communication device (e.g. WLAN, WiFi, Bluetooth, NFC, etc.) integrated in the sensor can be provided.

[0071] The position sensor 21 is configured to detect the distance to a calibration surface 22. The calibration surface 22 is assigned to a movable coupling 15 (pivoting element). The pivoting element 15 is supported rotatably about a pivot axis R and can be driven by a drive unit 19. In particular, the coupling 15 comprises or is formed as a shaft of the drive unit 19, in particular of a motor of the drive unit 19 or a gear of the drive unit 19. The calibration surface 22 may also be provided as a stop connected to the coupling 15.

[0072] The coupling 15 connects the valve closure member 14 to a drive unit 19 such that movability of the valve closure member 14 by the drive unit 19 is provided by the coupling 15 .

[0073] In one embodiment, the coupling 15 may be a motor shaft of a drive unit 19 provided as an electric motor.

[0074] In the closed position shown in Figures 2a and 2b, a first distance exists between the position sensor 21 and the surface 22. In the open position shown in Figures 3a and 3b, a second distance exists between the position sensor 21 and the surface 22. The second distance is greater than the first distance.

[0075] The coupling 15 provided for providing the mobility of the valve-closing member 14 typically has at least a very small bearing play relative to the valve seat due to manufacture, play being understood in this case to mean a movement space due to manufacture or use, in which a mechanical component can move freely relative to or together with another component of a component group or functional unit during or after assembly.

[0076] In particular, a compromise must be taken into account when designing and manufacturing vacuum valves between a large play, which is associated with a smooth movement of the valve closing member 14, and a small play, which is associated with a very precise positioning accuracy of the valve closing member 14. Since the precise positioning of the valve closing member 14 relative to the valve seat is important for a reliable sealing of the valve opening 12 and prevents excessive or premature wear of the sealing material, a small bearing play can typically be preferred. However, play cannot be completely avoided already in order to avoid high frictional forces in the bearings.

[0077] During the manufacture or assembly of the vacuum valve 10, the valve components are adjusted and assembled relative to one another in particular such that a corresponding movement of the valve closure member 14 can provide a precise closure of the valve opening 12. That is to say, a calibration is typically performed in such a way that a precise overlap of the first and second sealing surfaces occurs in the closed position of the valve closure member 14. However, such assembly and adjustment (calibration) of the valve 10 is always performed in a predefined orientation (calibration orientation) of the valve 10, for example in a horizontal orientation (see Figures 1a and 1b). If the valve is assembled in an orientation (assembly position) different from the calibration orientation, play in the gearing may adversely affect the functional reliability of the valve 10.

[0078] In particular, the mass of the valve closing member 14 causes the resulting weight to act in a particular direction depending on the orientation of the valve and thus also on the coupling 15 (in particular on the gearing and the support) in a different manner. The inertial forces caused by the movement of the closing member 14 also act correspondingly differently, in particular in different directions.

[0079] As a result, if the vacuum valve 10 is assembled in an assembly position different from the calibrated orientation, the valve closure member 14 may assume an attitude or position that is offset from the calibrated closed position upon reaching the closed position.

[0080] According to the invention, such deviations can be detected by distance measurement with the position sensor 21 and can be counteracted on the control side. An advantage of such a solution is also that no costly mechanical intervention is required to calibrate the valve in such an installation orientation, but the calibration can be carried out by the valve control.

[0081] According to the invention, a reference value for the distance between the calibration surface 22 and the sensor 21, which exists in the calibration orientation in the closed position, can first be defined. This reference value can correspondingly represent a target position (angular position about the pivot axis R) for the valve closing member 14 for reaching the closed position. In other words, the valve closing member 14 is in the target closed position when the reference value as distance is calculated. Such a calculation of the reference value is preferably carried out in the factory within the scope of the production of the vacuum valve.

[0082] Furthermore, a calibration value for the vacuum valve can be determined. In this case, the calibration value can be the distance between the calibration surface 22 and the position sensor 21, in which case the valve closing member 14 has been moved to the closed position, i.e. the valve closing member 14 is pivoted to the closed position by drive control of the drive unit by the control and processing unit (open loop). The end position of the valve closing member 14 reached in this case corresponds in particular to a predefined drive control value. The determination of the calibration value can preferably take place at the customer's side, for example after the valve has been installed in a production line.

[0083] As mentioned above, when determining the calibration value, deviations may occur between the predefined reference value and the calibration value, e.g. due to different valve orientations or e.g. due to repositioning of the motor (e.g. on the other valve side), such deviations can be derived and provided as calibration information by comparison of both values.

[0084] In one embodiment, an adaptation of the control functionality for the drive control of the drive unit can be carried out based on the calibration information. In particular, corresponding drive control parameters, such as, for example, end positions (angular positions about the pivot axis R), motor current, pivot duration, etc., can be adapted in such a way that the valve closing member 14 assumes a target closing position corresponding to a reference value when it reaches the closed position and also in the assembled position. This allows a position calibration to be carried out simply after assembly of the valve (at the customer's side), thus providing a reliability of the sealing action and a precision of the corresponding positioning of the sealing surfaces in the closed position.

[0085] Such calibration may occur, for example, after assembly of the valve 10 and / or at predetermined intervals, such as after a predetermined number of opening and closing movements or after a predetermined period of operation.

[0086] Figure 3a shows the pendulum valve 10 of Figure 1b in an open position in a cross-sectional view (cut in a plane perpendicular to the opening axis A). Figure 3b shows a part of the valve 10 of Figure 3a in the region of the drive unit 19.

[0087] The distance between the calibration surface 22 and the position sensor 21 is in this case greater than the distance in the closed position. Correspondingly to the above-described calibration of the position of the valve closing member 14 for the closed position, such a calibration can also be carried out for the open position. For this purpose, the distance in the target open position is defined as the reference value and the distance after the closing member 14 has been pivoted to the open position is defined as the calibration value.

[0088] 4 shows a cross-section in the edge region of the valve closing member 14 (valve plate) in the closed position. The valve plate 14 has a second sealing surface 16, on which a sealing member 17 (sealing material) is vulcanized or alternatively bonded. The second sealing surface 16 or the sealing material 17 is located in an opposing position to the first sealing surface 13 of the valve seat. If the valve closing member 14 is shown in an intermediate position representing the closed position, the sealing material 16 is not (yet) (or no longer) in contact with the first sealing surface 13, but the valve opening is covered by the valve closing member 14.

[0089] It should be understood that the figures shown only show possible embodiments in a schematic manner, and that the various measures can likewise be combined with one another and with prior art devices and methods.

Claims

1. A pendulum valve (10), in particular a vacuum pendulum valve for controlling a volumetric or mass flow rate and / or for opening and closing a valve opening (12), comprising: a valve seat defining the valve opening (12) defining an opening axis (A) and having a first sealing surface (13) surrounding the valve opening (12); a valve closing member (14) for controlling the volumetric or mass flow rate and / or for gas-tightly closing the valve opening (12), the valve closing member having a second sealing surface (16) corresponding to the first sealing surface (13), the valve closing member being supported so as to be pivotable about a pivot axis (R); a drive unit (19) coupled to the valve closing member (14), From an open position in which the valve closure member (14) at least partially opens the valve opening (12), to a closed position in which the valve closing member (14) is positioned above the valve opening (12) and covers the opening cross section of the valve opening (12); and return, so that the valve closing member (14) is positionably adjustable. a drive unit (19) configured to provide a pivotal movement of the valve closing member (14) about the pivot axis (R); A pendulum valve (10) having: The pendulum valve (10) a calibration surface (22); a position sensor (21) for detecting a distance between the position sensor (21) and the calibration surface (22); The position sensor (21) is disposed in a fixed position relative to the valve seat, and The calibration surface (22) is connected to the valve closing member (14) and is movably arranged so that the position of the calibration surface (22) and the distance between the position sensor (21) and the calibration surface (22) change during the pivoting movement of the valve closing member (14). A pendulum valve (10).

2. The pendulum valve (10) has a coupling (15), the coupling (15) connects the valve closing member (14) to the drive unit (19); the calibration surface (22) is provided on the coupling (15) or the valve closing member (14); The pendulum valve (10) of claim 1.

3. 3. The pendulum valve (10) according to claim 2, wherein the coupling (15) has a shaft and / or a transmission, and the calibration surface (22) is provided as a stopper connected to or molded together with the coupling (15).

4. 3. The pendulum valve (10) according to claim 2, wherein the coupling (15) is provided as a pivot element configured to be rotatable about a pivot axis.

5. The pendulum valve (10) has a control and processing unit (18) with control and calibration functions; the control function is configured to control the pivotal movement of the valve closure member (14); The calibration function, when performing the calibration, Detecting the distance between the calibration surface (22) and the position sensor (21) as a calibration value; Comparing the calibration value with a reference value to generate corresponding calibration information. The pendulum valve (10) of claim 1, wherein the pendulum valve (10) is configured as follows:

6. 6. The pendulum valve (10) according to claim 5, wherein the reference value is provided as a reference distance between the calibration surface (22) and the position sensor (21).

7. 7. The pendulum valve (10) according to claim 6, wherein the reference distance provides a distance between the calibration surface (22) and the position sensor (21) at a target closed position of the valve closing member (14), in which a projection of the first sealing surface (13) and a projection of the second sealing surface (16) onto a plane parallel to the first sealing surface (13) at least partially overlap, in particular completely overlap.

8. 8. The pendulum valve (10) of claim 7, wherein in the target closed position, the first sealing surface (13) and the second sealing surface (16) are concentrically arranged.

9. 7. The pendulum valve (10) of claim 5 or 6, wherein the reference value provides an angular position about the pivot axis for the valve closing member (14).

10. 7. The pendulum valve (10) of claim 5 or 6, wherein the calibration value is determined at the closed position of the valve closure member (14).

11. 7. Pendulum valve (10) according to claim 5 or 6, wherein within the scope of the calibration function, the control function is adapted depending on the calibration information.

12. the calibration information indicating a deviation of the calibration value from the reference value; the control function is adapted so that, during the pivoting movement of the valve closing member (14) to the closed position, the closed position reached thereby corresponds to a target closed position of the valve closing member (14). The pendulum valve (10) according to claim 11.

13. 7. The pendulum valve (10) according to claim 5, wherein the current position of the valve closing member (14) relative to the valve seat can be calculated based on the detected distance between the position sensor (21) and the calibration surface (22).

14. 2. A method for calibrating a pendulum valve (10) according to claim 1, comprising: Detecting the distance between the calibration surface (22) and the position sensor (21) as a calibration value; comparing the calibration value with a reference value, the reference value providing a reference distance between the calibration surface (22) and the position sensor (21); providing calibration information indicative of deviation of the calibration value from the reference value; and - adapting control of the pivoting movement of the valve closing member (14) based on the calibration information so that, during the pivoting movement of the valve closing member (14) to a closed position, the closed position reached thereby corresponds to a target closed position. The method has the following features:

15. A computer program product comprising a program code stored on a machine-readable carrier, in particular in a control and processing unit of a pendulum valve (10) according to claim 5, or a computer data signal embodied by electromagnetic waves for implementing or controlling the steps of the method according to claim 14.

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