VACUUM VALVE WITH POSITION SENSOR

Abstract

Disclosed is a vacuum valve having a valve closure and having a drive unit which is coupled to the valve closure and which has at least one adjustment element. The vacuum valve furthermore has a position sensor, in particular a travel or distance sensor, such that a position of the valve closure and/or of the at least one adjustment element relative to a zero position, in particular an open position or closed position of the vacuum valve, can be measured.

Claims

1. A vacuum valve, including a vacuum slide valve, pendulum valve, or monovalve, for a regulation of a volume or mass flow and/or for a gas-tight interruption of a flow path, comprising: a valve seat, which has a valve opening defining an opening axis and a first sealing surface circumferential around the valve opening, a valve closure for the regulation of the volume or mass flow and/or for the interruption of the flow path, comprising a second sealing surface corresponding to the first sealing surface; a drive unit coupled to the valve closure, comprising at least one movable adjustment element, wherein the drive unit is configured to execute an adjustment movement, such that the valve closure is movable to and from an open position, in which the valve closure and the valve seat are provided without contact in relation to one another, and a closed position, in which an axially sealing contact with respect to the opening axis exists between the first sealing surface and the second sealing surface, via a seal, and the valve opening is thus closed gas-tight, wherein the vacuum valve further comprises at least one position sensor, wherein the at least one position sensor is arranged in the vacuum valve such that, in an ongoing manner, a position of the valve closure or the at least one movable adjustment element is measurable with respect to a null position, the open position, or the closed position, and wherein at least one of the following is satisfied, including: the at least one position sensor being arranged in the vacuum valve such that a position measurement is performed via the at least one position sensor with respect to at least two adjustment directions of the valve closure essentially orthogonal to one another, or the at least one position sensor including at least two position sensors, which are arranged in the vacuum valve such that a position with respect to a first adjustment direction is measurable by a first position sensor and a position with respect to a second adjustment direction is measurable by a second position sensor, the first adjustment direction and the second adjustment direction being essentially orthogonal to one another.

2. The vacuum valve according to claim 1, wherein the at least one position sensor is arranged in the vacuum valve such that a time curve of at least a part of the adjustment movement is determinable, such that at least one velocity of the adjustment movement is determinable for at least one time span of the adjustment movement.

3. The vacuum valve according to claim 1, wherein the at least one position sensor includes a displacement sensor, a distance sensor, or an absolute position sensor.

4. The vacuum valve according to claim 1, wherein the adjustment movement comprises at least an essentially linear adjustment movement, and the at least one position sensor is arranged to acquire at least a part of the linear adjustment movement, wherein the at least one position sensor includes a linear encoder.

5. The vacuum valve according to claim 1, wherein the adjustment movement comprises at least an essentially rotational adjustment movement, and the at least one position sensor is arranged to acquire at least a part of the rotational adjustment movement, wherein the at least one position sensor includes an angle encoder.

6. The vacuum valve according to claim 1, wherein the at least one position sensor includes an inductive position sensor, an optical position sensor, a magnetic position sensor, a magnetostrictive position sensor, a potentiometric position sensor, or a capacitive position sensor.

7. The vacuum valve according to claim 1, wherein the at least one position sensor is arranged outside a vacuum range separated from an external environment by the vacuum valve in a defined manner.

8. The vacuum valve according to claim 1, wherein the valve seat is formed by a part of the vacuum valve connected structurally to the vacuum valve, wherein the valve seat is formed on a housing of the vacuum valve, or is provided by a process chamber or a chamber housing.

9. The vacuum valve according to claim 1, further comprises a processing unit that processes an acquired position sensor measurement signal, and wherein an item of state information of the vacuum valve is ascertained based on the acquired measurement signal.

10. The vacuum valve according to claim 9, wherein the item of state information is provided with respect to a mechanical and/or structural integrity of the valve closure or the at least one movable adjustment element, wherein the item of state information is ascertained based on an actual-setpoint comparison for the acquired measurement signal.

11. The vacuum valve according to claim 9, wherein based on a comparison of the item of state information to predefined tolerance values, an output signal is provided with respect to an evaluation of a process controlled by the vacuum valve.

12. The vacuum valve according to claim 1, further comprising: a processing unit configured to determine appearance of wear of the first sealing surface or the second sealing surface based on position measurements from the at least one position sensor, and output a signal based on the determined appearance of wear.

13. A method for monitoring a vacuum valve, including a vacuum slide valve, pendulum valve, or monovalve, regulating, via the vacuum valve, a volume or mass flow and/or for a gas-tight interruption of a flow path, the vacuum valve having a valve seat, which has a valve opening defining an opening axis and a first sealing surface circumferential around the valve opening, a valve closure comprising a second sealing surface corresponding to the first sealing surface, and a drive unit coupled to the valve closure, comprising at least one movable adjustment element; executing, via the drive unit, an adjustment movement, such that the valve closure being movable to and from an open position, in which the valve closure and the valve seat are provided without contact in relation to one another, and a closed position, in which an axially sealing contact with respect to the opening axis exists between the first sealing surface and the second sealing surface, via a seal, and the valve opening is thus closed gas-tight; measuring, via at least one position sensor, a position of the valve closure in an ongoing manner, position measurements are performed regarding at least two adjustment directions essentially orthogonal to one another, and regarding an absolute position of the valve closure or regarding the at least one movable adjustment element with respect to a null position, the open position, or the closed position; and processing, via a processing and control unit, to monitor the vacuum valve based on the measured position.

14. The method according to claim 13, further comprising: ascertaining an item of state information of the vacuum valve, with respect to a mechanical or structural integrity of the valve closure or the at least one movable adjustment element, based on the position measurements, wherein the item of state information is ascertained based on an actual-setpoint comparison for the position measurements or based on a comparison of the item of state information to predefined tolerance values; and outputting an output signal with respect to an evaluation of a process controlled by the vacuum valve.

15. The method according to claim 13, further comprising: determining, based on the position measurements, an adjustment velocity of the valve closure or the at least one movable adjustment element at least for a part of the adjustment movement, or a duration of the adjustment movement from the open position to the closed position or vice versa.

16. The method according to claim 13, further comprising: performing, by the processing and control unit based on the position measurements, a detection of: an end location, the open position, or the closed position of the valve closure or the at least one movable adjustment element, a possible impact of the first sealing surface and the second sealing surface on one another in a scope of the adjustment movement, or a possible adhesion of the first sealing surface and the second sealing surface on one another.

17. A non-transitory machine-readable medium storing a computer program which, when being executed by a control and processing unit of a vacuum valve, causes the vacuum valve to perform a method comprising: regulating, via the vacuum valve, a volume or mass flow and/or for a gas-tight interruption of a flow path, the vacuum valve having a valve seat, which has a valve opening defining an opening axis and a first sealing surface circumferential around the valve opening, a valve closure comprising a second sealing surface corresponding to the first sealing surface, and a drive unit coupled to the valve closure, comprising at least one movable adjustment element; executing, via the drive unit, an adjustment movement, such that the valve closure being movable to and from an open position, in which the valve closure and the valve seat are provided without contact in relation to one another, and a closed position, in which an axially sealing contact with respect to the opening axis exists between the first sealing surface and the second sealing surface, via a seal, and the valve opening is thus closed gas-tight; measuring, via at least one position sensor, a position of the valve closure in an ongoing manner, position measurements are performed regarding at least two adjustment directions essentially orthogonal to one another, and regarding an absolute position of the valve closure or regarding the at least one movable adjustment element with respect to a null position, the open position, or the closed position; and monitoring the vacuum valve based on the measured position.

Description

[0049] The Figures Show in Detail:

[0050] FIG. 1a, b show a possible first embodiment of a vacuum valve according to the invention as a monovalve;

[0051] FIG. 2 shows a possible second embodiment of a vacuum valve according to the invention as a monovalve;

[0052] FIGS. 3a-c show a possible further embodiment of a vacuum valve according to the invention as a transfer valve;

[0053] FIG. 4a, b show a schematic illustration of a further embodiment according to the invention of a vacuum valve as a pendulum valve;

[0054] FIG. 5a, b show a schematic illustration of a further embodiment according to the invention of a vacuum valve as a transfer valve; and

[0055] FIG. 6a, b show a schematic illustration of a further embodiment according to the invention of a vacuum valve as a transfer valve.

[0056] FIGS. 1a, 1b schematically show a first embodiment of a vacuum valve 1 according to the invention. In the example, the valve 1 is embodied as a so-called monovalve and is shown in cross-section in an open position O (FIG. 1a) and a closed position G (FIG. 1b).

[0057] The valve 1, for the gas-tight closing of a flow path by means of a linear movement, has a valve housing 24 comprising an opening 2 for the flow path, wherein the opening 2 has a geometrical opening axis H along the flow path. The opening 2 connects a first gas region L, which is located in the drawing on the left of the valve 1 and/or a partition wall (not shown), to a second gas region R on the right thereof. Such a partition wall is formed, for example, by a chamber wall of a vacuum chamber.

[0058] The closure element 4 is displaceable linearly along a geometric adjustment axis V, which extends transversely to the opening axis H, in a closure element plane 22 from an open position O, which releases the opening 2, into a closed position G, which is pushed linearly over the opening 2, in a closing direction and vice versa back in an opening direction by means of a drive unit 7 having a movable positioning element 5, in the example an adjustment arm.

[0059] For example, a curved first sealing surface 3 encloses the opening 2 of the valve housing 24 along a first section 21a in a first plane 20a and along a second section 21b in a second plane 20b. The first plane 20a and the second plane 20b are spaced apart from one another, extend parallel to one another, and extend parallel to the closure element plane 22. The first section 21a and the opposing second section 21b therefore have a geometric offset in relation to one another transversely to the adjustment axis V and in the direction of the opening axis H. The opening 2 is arranged between the two opposing sections 21a and 21b in the region extending along the adjustment axis V.

[0060] The closure element 4 has a second sealing surface 6, which extends along sections corresponding to the first and second sections 21a, 21b, corresponding to the first sealing surface 3.

[0061] Monovalves, i.e., vacuum valves closable by means of a single linear movement, have the advantage, for example, of a comparatively simple closing mechanism, for example, compared to the transfer valves closable by means of two movements, which require a comparatively complexly constructed drive. Since the closure element can moreover be formed in one piece, it can be subjected to high acceleration forces, and therefore this valve can also be used for rapid and emergency closures. The closing and sealing can take place by means of a single linear movement, and therefore very rapid closing and opening of the valve 1 is possible.

[0062] In particular, one advantage of monovalves is, for example, that the seal 3, 6, because of its profile during closing, is not subjected to a transverse load in the transverse direction in relation to the longitudinal extension of the seal 3, 6. On the other hand, the seal 3, 6 is hardly capable, because of its transverse extension in relation to the opening axis H, of absorbing forces occurring on the closure element 4 along the opening axis H, which can act on the closure element 4 in particular in the case of large differential pressure, which requires a robust construction of the closure element 4, its drive, and its mounting.

[0063] According to the invention, the vacuum valve 1 shown in FIGS. 1a and 1b comprises a displacement sensor 10, which in the example has a position-transducing element (target) 8 and a sensor surface 9 (ruler) for the detection thereof. The displacement sensor 10 is designed, for example, as a (contactless) inductive displacement sensor, for example, a differential transformer having displaceable core, a pulsed inductive linear position sensor, PLCD displacement sensor (permanent linear contactless displacement sensor), optoelectronic displacement sensor, potentiometric displacement sensor, magnetostrictive displacement sensor, capacitive displacement sensor, or magnetic displacement sensor. Depending on the sensor 10, the ruler 9 is active and the position-transducing element 8 is passive or vice versa, i.e., the (electrical or electronic) measurement signal and/or analysis signal is generated or tapped either by the ruler 9 or element 8, respectively.

[0064] In the example, the target 8 is fastened on or in the adjustment element 4, and therefore it moves with it along the adjustment axis V. The sensor surface 9 extends in the adjustment direction V at least over the entire adjustment distance, and therefore the position of the target 8 and thus the adjustment element 4 is measurable over the entire possible linear movement of the adjustment element 4. The position is ascertained in this case in relation to a starting or null position, which is preferably either the open position O or the closed position G. The displacement sensor 10 is preferably an absolute encoder in this case. Alternatively, an incremental displacement sensor is used.

[0065] The actual position of the adjustment element 4 can thus advantageously be determined by means of the position sensor 10. The position measurement can be restricted in this case to the determination of one or a few positions, preferably the end position (i.e., open position O and/or closed position G), for example, in the meaning of an end location detection. However, an ongoing or continuous position determination preferably takes place, and therefore the position of the adjustment element 4 is known progressively and in particular the time curve thereof is known.

[0066] By way of the sensor arrangement according to the invention, for example, the closing capability of the valve can therefore be checked during a process sequence, the contact pressure can be regulated accordingly, and a failure of the leak-tightness can possibly be predicted. In particular, for example, the compression can be set individually using an electric drive unit 7. Using a pneumatic drive 7, it can at least be checked using the sensor arrangement whether the valve is closed.

[0067] The knowledge of the chronological movement curve is optionally used to determine the velocity of the linear movement of the closure element 4 therefrom. This can advantageously be used for an improved end location determination, whereby tolerances in the vacuum valve become less critical. The exact duration for the closing or opening procedure may thus also be ascertained, whereby, for example, optimizations or fault recognition are enabled. In general, an analysis of the time-displacement curve, which is performed, for example, by an external data processing system, to which the position sensor 10 and/or the vacuum valve 1 is connected, enables inferences about the state of the valve 1. Irregularities or changes in the course of the operating cycles can thus be recognized, and the state of the moving components or the sealing surfaces 3, 6 can thus be concluded, for example. If the two sealing surfaces 3, 6 adhere to one another in the closed position G, for example, it is thus recognizable in the movement sequence, since the position of the adjustment element 4 remains constant for a certain length of time because of the adhesive force, although it is driven by the drive unit 7 via the adjustment element 5, followed by a rapid opening movement and a brief recoil.

[0068] FIG. 2 shows an alternative to the embodiment according to FIGS. 1a, 1b. In this example, the vacuum valve 1 has a position sensor 10 designed as a distance sensor. The distance sensor 10 is, for example, an optoelectronic distance sensor or an ultrasonic sensor and emits a corresponding measurement signal 13 by means of an emitter, for example, laser light, in the direction of the adjustment element 4 and/or the vertical axis V, and therefore the signal 13 is incident on the adjustment element 4 (in the example on its rear surface), is at least partially reflected therefrom, and is received again by a detector of the sensor 10. In this case, the distance between sensor 10 and adjustment element 4 and therefore the position of the adjustment element 4 is determined by means of determination of the signal runtime (pulse runtime method) and/or phase difference measurement, phase or frequency runtime methods, and/or according to the Fizeau principle. As a further option, a position determination takes place by means of triangulation.

[0069] To improve the distance and/or position measurement, in the example, the vacuum valve 1 has a reflector 14 arranged on the adjustment element, which is designed to reflect the measurement signal 13 toward the sensor 10 and thus improve the signal level of the received measurement signal 13. Alternatively to the illustrated arrangement, the sensor 10 is arranged on the moving part, i.e., on the closure 4 here, and emits measurement radiation 13 toward a static point of the valve 1 (i.e., an inverted arrangement from the illustration).

[0070] FIGS. 3a-3c show a further embodiment of a vacuum valve 1 according to the invention, which is designed in the example as a transfer valve, illustrated in different closure positions.

[0071] The transfer valve shown is a special form of a slide valve. The vacuum valve has a rectangular, plate-shaped closure element 4 (for example, valve plate), which has a sealing surface 6 for the gas-tight closing of an opening 2. The opening 2 has a cross-section corresponding to the closure element 4 and is formed in a wall 12. The opening 2 is enclosed by a valve seat, which in turn also provides a sealing surface 3 corresponding to the sealing surface 6 of the closure element 4. The sealing surface 6 of the closure element 4 is circumferential around the closure element 4 and has a sealing material (seal). In a closed position, the sealing surfaces 6, 3 are pressed against one another and the sealing material is compressed at the same time.

[0072] The opening 2 connects a first gas region L, which is located on the left of the wall 12, to a second gas region R on the right of the wall 12. The wall 12 is formed, for example, by a chamber wall of a vacuum chamber. The vacuum valve 1 is then formed by an interaction of the chamber wall 12 with the closure element 4.

[0073] The closure element 4 is arranged on an adjustment arm 5, which is rod-shaped here, for example, and which extends along a geometric adjustment axis V. The adjustment arm 5 is mechanically coupled to a drive unit 7, by means of which the closure element 4 is adjustable in a first gas region L on the left of the wall 12 by adjustment of the adjustment arm 5 by means of the drive unit 7 between an open position O (FIG. 3a) via an intermediate position Z (FIG. 3b) into a closed position G (FIG. 3c).

[0074] In the open position O, the closure element 4 is located outside the projection region of the opening 2 and releases it completely, as shown in FIG. 3a.

[0075] By adjusting the adjustment arm 5 in the axial direction parallel to the first, “vertical” adjustment axis V and parallel to the wall 12, the closure element 4 can be adjusted by means of the drive unit 7 from the open position O into the intermediate position Z.

[0076] In this intermediate position Z (FIG. 3b), the sealing surface 6 of the closure element 4 overlaps the opening 2 and is located in a position spaced apart opposite to the sealing surface 3 of the valve seat enclosing the opening 2.

[0077] By adjusting the adjustment arm 5 in the direction of the second “horizontal” adjustment axis H (transversely to the first adjustment axis V), i.e., for example, perpendicularly to the wall 12 and to the valve seat, the closure element 4 can be adjusted from the intermediate position Z into the closed position G (FIG. 3c).

[0078] In the closed position G, the closure element 4 closes the opening 2 in a gas-tight manner and separates the first gas region L from the second gas region R in a gas-tight manner.

[0079] The opening and closing of the vacuum valve thus takes place by means of the drive unit 7 by way of an L-shaped movement in two directions H, V perpendicular to one another of the closure element 4 and the adjustment arm 5. The transfer valve shown is therefore also called an L-type valve.

[0080] A transfer valve 1 as shown is typically provided for sealing a process volume (vacuum chamber) and for loading and unloading the volume. Frequent changes between the open position O and the closed position G are the rule in the case of such a use. Increased appearances of wear of the sealing surfaces 6, 3 and the mechanically moved components, for example, the adjustment element 5 or other parts of the drive unit 7, can thus occur.

[0081] For early determination of such appearances of wear, among other things, the vacuum valve 1 according to the invention has a position sensor 10, which is designed in the example as a two-axis displacement sensor. In contrast to the embodiment according to the example of FIG. 1a, b, a position is determined in both adjustment directions V, H by means of a target 8 attached to the adjustment element 5. For this purpose, the vacuum valve 1 has a first “vertical” ruler 9v for the position determination of the “vertical” movement between the open position O to the intermediate position Z and a second, “horizontal” ruler 9h for the position determination of the “horizontal” movement between the intermediate position Z and the closed position G. By means of the target 8 arranged on the adjustment element 5 and the first ruler 9v, in sequential sequence according to the sequential movement sequence open position O—intermediate position Z—closed position G (or vice versa), the position of the adjustment element 5 is thus measured in the first, “vertical” adjustment direction V, and by means of the target 8 and the second ruler 9h, the position is measured in the second, “horizontal” adjustment direction H.

[0082] In the example, the valve 1 and/or the position sensor 10 furthermore has a control and/or analysis unit 11, using which the position measurement is controlled and/or position data are recorded or analyzed, and therefore, for example, an external computer can (substantially) be dispensed with and, for example, solely valve-internal monitoring or state monitoring of the valve 1 takes place.

[0083] Alternatively to the illustrated sequentially arranged two linear rulers 9v, 9h, a single 2D sensor surface is used (not shown), which is optically scanned, for example, and therefore a simultaneous determination of the position of the adjustment element 5 in both axes or directions V and H is enabled.

[0084] As a further alternative, the position determination with respect to the two adjustment directions V, H or the two adjustment movements does not take place by means of a single position sensor 10, but rather the valve 1 has one position sensor 10 for each adjustment direction V, H or adjustment movement, and thus comprises two position sensors 10.

[0085] FIG. 4a and FIG. 4b schematically show a further possible embodiment of the valve according to the invention in the form of a pendulum valve 1. The valve 1 for the essentially gas-tight interruption of a flow path has a valve housing, which has an opening 2. The opening 2 has a circular cross-section here, for example. The opening 2 is enclosed by a valve seat. This valve seat is formed by a (first) sealing surface 3, which faces axially in the direction of a valve plate 4 and extends transversely to the opening axis H, has the shape of a circular ring, and is formed in the valve housing. The valve plate 4 is pivotable around an axis of rotation R and is adjustable essentially parallel to the opening axis H. In a closed position G (FIG. 4b) of the valve plate 4 (valve closure), the opening 2 is closed gas-tight by means of the valve plate 4, which has a second sealing surface 6. An open position O of the valve plate 4 is illustrated in FIG. 4a.

[0086] The valve plate 4 is connected via an arm 5, which is arranged laterally on the plate and extends perpendicularly to the opening axis H, to a drive unit 7. This arm 5 is located, in the closed position G of the valve plate 4, outside the opening cross-section of the opening 2 geometrically projected along the opening axis H.

[0087] The drive 7 is designed by use of a motor and a corresponding gearing such that the valve plate 4—as is typical in a pendulum valve—is pivotable by means of a transverse movement x of the drive 7 transversely to the opening axis H and essentially parallel over the cross-section of the opening 2 and perpendicularly to the opening axis H in the form of a pivot movement Br around the pivot axis R between an open position O and an intermediate position and is linearly displaceable by means of a longitudinal movement Bv of the drive 7 occurring parallel to the opening axis 5. In the open position O, the valve plate 4 is positioned in a dwell section arranged laterally adjacent to the opening 2, and therefore the opening 2 and the flow path are released. In the intermediate position, the valve plate 4 is positioned spaced apart above the opening 2 and covers the opening cross-section of the opening 2. In the closed position, the opening 2 is closed gas-tight and the flow path is interrupted, in that a gas-tight contact exists between the sealing surface 6 of the valve closure 4 (valve plate) and the sealing surface 3 of the valve seat.

[0088] To enable automated and regulated opening and closing of the valve 1, the valve 1 provides, for example, an electronic regulating and control unit (not shown), which is designed and is connected to the drive 7 such that the valve plate 4 is adjustable accordingly for the gas-tight termination of a process volume or for the regulation of an internal pressure of this volume.

[0089] In the present exemplary embodiment, the drive 7 is designed as an electric motor, wherein the gearing is switchable such that driving of the drive 78 causes either the transverse movement Br or the longitudinal movement Bv. The drive including gearing is electronically activated by the regulator. Such gearings, in particular having slotted link shift units, are known from the prior art. It is furthermore possible to use multiple drives to cause the rotational movement Br and the linear movement Bv, wherein the controller assumes the activation of the drives.

[0090] The precise regulation and/or setting of the flow rate using the described pendulum valve 1 is possible not only by way of the pivoting adjustment of the valve plate 4 between the open position O and the intermediate position by means of the transverse movement Br, but rather above all by linear adjustment of the valve plate 4 along the opening axis H and/or R between the intermediate position and the closed position by means of the longitudinal movement Bv. The described pendulum valve can be used for precise regulating tasks.

[0091] Both the valve plate 4 and also the valve seat each have a sealing surface—a first and a second sealing surface 3, 6. The first sealing surface 3 moreover has a seal 23. This seal 23 can be, for example, vulcanized as a polymer by means of vulcanization onto the valve seat. Alternatively, the seal 23 can be embodied, for example, as an O-ring in a groove of the valve seat. A sealing material can also be adhesively bonded onto the valve seat and thus embody the seal 23. In an alternative embodiment, the seal 23 can be arranged on the side of the valve plate 4, in particular on the second sealing surface 6. Combinations of these embodiments are also conceivable. Such seals 23 are of course, not restricted to the valve 1 described in the example, but rather are also applicable in the further described valve embodiments.

[0092] The valve plate 4 is variably set, for example, on the basis of regulating variables and an output control signal. An item of information about a present pressure state in a process volume connected to the valve 1, for example, is received as an input signal. Moreover, a further input variable, for example, a mass inflow into the volume, can be provided to the regulator. On the basis of these variables and on the basis of a predefined setpoint pressure, which is to be set or achieved for the volume, a regulated setting of the valve 1 then takes place over the time of a regulating cycle, and therefore a mass outflow out of the volume can be regulated over time by means of the valve 1. For this purpose, a vacuum pump is provided behind the valve 1, i.e., the valve 1 is arranged between the process chamber and the pump. A desired pressure curve can thus be modulated.

[0093] A respective opening cross-section for the valve opening 2 is set by the setting of the valve closure 4 and thus the possible gas quantity is set which can be evacuated per unit of time out of the process volume. The valve closure 4 can have a shape deviating from a circular shape for this purpose, in particular to achieve the most laminar possible media flow.

[0094] To set the opening cross-section, the valve plate 4 is adjustable by the regulating and control unit by means of the transverse movement Br of the drive 7 from the open position O into the intermediate position and by means of the longitudinal movement Bv of the drive 7 from the intermediate position into the closed position. To completely open the flow path, the valve plate 4 is adjustable by the controller by means of the longitudinal movement Bv of the drive 7 from the closed position G into the intermediate position and therefrom by means of the rotational movement Br of the drive 7 from the intermediate position into the open position O.

[0095] The pressing of the valve plate 4 onto the valve seat has to take place such that both the required gas-tightness is ensured within the entire pressure range, and also damage to the valve 1, or more precisely the sealing surfaces 3, 6 or the seal(s) 23 due to excessively large pressure strain is avoided. To ensure this, known valve plates provide a contact pressure regulation of the valve plate 4 regulated as a function of the pressure difference prevailing between the two valve plate sides.

[0096] According to the invention, the valve 1 has two position sensors 10 and 10′, designed in the example as linear encoder 10 and angle encoder 10′.

[0097] The linear position sensor 10 has a scale 9, which extends on the arm 5 along the linear movement direction Bv on the arm 5 and is therefore movable in the feed direction Bv in relation to the stationary part of the valve 1, i.e., for example, in relation to the valve housing or the drive unit 7. The respective relative position is ascertained by the linear encoder by means of a read head 8, which scans the scale 9, which has a position code for this purpose. The scale 9 and/or the read head are formed at least partially “wide” in this case such that a linear position is also measurable in different rotational positions of the arm 5. The scale 9 thus extends, for example, far enough around the arm 5 that a part thereof is opposite to the detector 8 both in the open position O and also in the closed position G and the scale 9 cannot be pivoted out of the “field of vision” of the detector 8.

[0098] The position code is preferably an absolute position code. Alternatively, the position code is an incremental code. In absolute position sensors 10, 10′, a position can be associated directly with every relative location of read head 8 to scale 9 (which is related to a previously defined null position), in that the scale 9 has an absolute position code made of unique code words over the entire measurement distance, which can be associated with precisely one position by a control and analysis unit. In position encoders 10, 10′ having incremental determination of positions, in contrast, the scanning signals are not unique, but rather repeat multiple times over the entire measurement range. The distance to which an increment corresponds is stored in a control and analysis unit of the encoder. The distance which is covered during a relative movement of scale 9 and read head 8 can therefore be saved, and a relative position can thus be determined by counting the increments. To locate such a relative position in an absolute manner, in the case of a relative movement, one proceeds from a defined null position as an absolute reference point. Such a null position or null point is defined, for example, by a position reference marker, which is detected by the read head 8, on the scale 9 (or in the case of a stationary scale 9 on the read head 8). Sensors 10, 10′ having incremental determination of translation locations or angles therefore have the disadvantage that in the event of a restart of the measurement system, one has to proceed each time from a null or reference position. In contrast, absolute linear or angle encoders generate unique differentiable scanning signals for each relative location of the parts which can be translated or rotated in relation to one another. A unique linear position and/or a unique angle can thus be associated directly with a respective relative location, i.e., without approaching a reference or starting position.

[0099] The second position sensor 10′ designed as an angle encoder also has a scale 9′, having an absolute or incremental angle coding, which is scanned by a read head 8′, and therefore an item of information can be obtained about the angle position of the arm 5 and thus of the valve plate 4. In the example, the scale 9′ extends at least partially around the arm 5 (at least enough that the circumference of the rotational movement Br is covered thereby), and therefore it is rotatable with the arm 5 in relation to the stationary detector 8′ or the entire stationary part of the valve 1.

[0100] By means of the first and second position sensor 10, 10′, the location of the movable parts of the valve 1, in particular the valve plate 4, and thus the state of the vacuum valve 1, in particular with respect to gas-tightness and/or required reliability of the gas-tight closing capability, can thus advantageously be monitored and evaluated in an ongoing manner.

[0101] Alternatively to a pendulum valve 1 as shown, the vacuum valve 1 according to the invention can be implemented using another vacuum valve type, for example, a flap valve, slide valve, or a so-called butterfly control valve. Furthermore, pendulum valves are also usable, the closure of which can only be adjusted in one direction.

[0102] FIGS. 5a and 5b schematically show a further possible position sensor arrangement in transfer valves according to the invention, illustrated in a closed position G (FIG. 5a) and an open position O (FIG. 5b). In the figures shown, the valve seat 3 is formed on a housing 24 of the vacuum valve 1. However, it is clear to a person skilled in the art that the following description is applicable essentially similarly to embodiments, wherein the valve seat is provided by a process chamber, i.e., a chamber housing.

[0103] Furthermore, it is apparent that the valve mechanism, which is illustrated here solely schematically as a tilt mechanism, is not to be understood as restrictive and a person skilled in the art can transfer the sensor arrangement according to the invention in a similar manner, for example, to an arbitrary L-motion drive, for example, an L-motion drive having two linear adjustment directions of the valve plate perpendicular to one another.

[0104] For the monitored guiding of the adjustment arm 5, the vacuum valve 1 has here, for example, a guide component 15, wherein the drive unit 7 and the guide component 15 are each in a fixed arrangement in relation to one another, here, for example, in that both the drive unit 7 and also the guide component 15 are each connected fixed in place to the valve housing 24. The adjustment arm 5 is furthermore mechanically coupled to the valve closure 4 and the drive unit 7, wherein by adjusting the valve arm 5 by means of the drive unit 7, the valve closure 4 is adjustable between the open position O and the closed position G essentially parallel to the valve seat, in particular in an L-motion movement as described in FIG. 3a to 3c.

[0105] According to the invention, the guide component has a position sensor 10. The position sensor 10 is designed in this case such that both the “vertical” component V of the movement of the arm 5 and/or the valve plate 4 can be measured, and also the “horizontal” component H thereof. The position sensor 10 has a rotary encoder for this purpose, for example, which is used both for determining the tilt position of the arm 5 (i.e., the “horizontal” component) and also its linear translation, in that it is converted beforehand into a rotational movement. Alternatively to the illustration, two separate position sensors are used and/or the position sensor or sensors are arranged at another point in the valve, for example, on the drive 7.

[0106] FIGS. 6a and 6b show, similarly to FIGS. 5a, 5b, a further possible embodiment of a vacuum valve 1 according to the invention. In contrast to the embodiment according to FIGS. 5a, 5b, the position sensor 10 for measuring the position of the valve closure 4 and/or the adjustment element 5 is designed here as a system having an illumination means 16, for example, an LED, for illuminating the rear end of the adjustment arm 5 and a camera system 17 for acquiring illumination radiation reflected from the adjustment arm 5. The camera system 17 has, for example, a position-sensitive detector, and therefore a position of the adjustment arm 5 can be concluded from radiation reflected from the incidence position onto the detector. Alternatively, for example, a generation of an image by means of the acquired radiation and an image analysis are performed, such that a position is determinable therefrom. Camera-based position determinations are known in principle from the prior art. The use of a pattern which can be optically acquired to improve imaging position determination is also known. Accordingly—as shown—the rear end of the adjustment element 5 has such an optical pattern 18. The “horizontal” position of the adjustment element 5 can be concluded from the position of the pattern 18 in the camera image, and its “vertical” position (distance to the camera) can be concluded from the imaged size of the image pattern, or from parts thereof (in comparison to a stored reference variable).

[0107] It is obvious that these illustrated figures only schematically illustrate possible exemplary embodiments. The various approaches can also be combined with one another and with methods and devices of the prior art.