DE102024111818A1 - Method for operating a pneumatic system and pneumatic system for industrial automation - Google Patents

Abstract

The invention relates to a method for operating a pneumatic system (11) for industrial automation, comprising at least one pneumatic actuator (14; 14a, 14b) and a control device (13) for controlling a movement of an actuator element (27; 27a, 27b) of the at least one pneumatic actuator (14; 14a, 14b) from a first end position (30) to a second end position (31) and/or from the second end position (31) to the first end position (30), wherein the actuator element (27; 27a, 27b) is motionally coupled to an end element (33) which can be driven by a stroke movement comprising a vertical stroke (h _{_z} ) and a horizontal stroke (h _{_x} ), comprising the steps:
- Determining a position of the end member (33) by means of a position measuring device (40), wherein the position of the end member (33) during the vertical stroke (h _z ) is determined by means of a first position measuring unit (41a) and the position of the end member (33) during the horizontal stroke (h _x ) is determined by means of a second position measuring unit (41b),
- Providing the determined position as an actual position signal to the control device (13),
- Implementation of position control based on the actual position signal recorded by the position measuring device (40).

Description

The invention relates to a method for operating a pneumatic system for industrial automation and a pneumatic system for industrial automation.

Methods for operating a pneumatic system for industrial automation, as well as pneumatic systems for industrial automation, are used in many areas.

One example is the wafer manufacturing area, where a large number of pneumatic actuators are typically used to move various types of control elements, such as spool valves that open or close a gate to a processing chamber for wafer processing. Overall, wafer manufacturing places high demands on the operation of pneumatic systems, including minimizing vibrations during spool valve operation. Furthermore, the sensors used to operate the pneumatic system must be simple and reliable.

However, such pneumatic systems are not only suitable for wafer production, but also for industrial automation in general. Depending on the application, different requirements arise for the pneumatic system.

The object of the invention is to provide a method for operating a pneumatic system and a pneumatic system that is improved compared to conventional methods or systems, in order to meet the requirements in particular for semiconductor/especially wafer production.

The foregoing problem is solved by a method for operating a pneumatic system for industrial automation with the features of independent claim 1 and by a pneumatic system for industrial automation with the features of independent claim 9. Further developments of the invention are described in the dependent claims.

• - Bestimmen einer Position des Endglieds mittels einer Positionsmesseinrichtung, wobei mittels einer ersten Positionsmesseinheit die Position des Endglieds während des vertikalen Bewegungshubs unmittels einer zweiten Positionsmesseinheit die Position des Endglieds während des horizontalen Bewegungshubs bestimmt wird,
• - Bereitstellen der bestimmten Position als Ist-Positionssignal an die Regelungseinrichtung,
• - Durchführung einer Positionsregelung auf Basis des mit der Positionsmesseinrichtung erfassten Ist-Positionssignals.

In the method for operating a pneumatic system for industrial automation, at least one pneumatic actuator and a control device for controlling a movement of an actuator element of the at least one pneumatic actuator from a first end position to a second end position and/or from the second end position to the first end position are provided, wherein the actuator element is motion-coupled with an end element that can be driven by a stroke movement comprising a vertical stroke and a horizontal stroke, wherein the method comprises the following steps:

• - Determining the position of the end member by means of a position measuring device, wherein the position of the end member during the vertical stroke is determined by means of a first position measuring unit and the position of the end member during the horizontal stroke is determined by means of a second position measuring unit.
• - Providing the specified position as an actual position signal to the control device,
• - Implementation of position control based on the actual position signal recorded by the position measuring device.

The pneumatic system according to the invention, in particular for carrying out the method with the features of claim 1, comprises at least one pneumatic actuator, with an actuator element, a control device for controlling a movement of the actuator element from a first end position to a second end position and/or from the second end position to the first end position, wherein the actuator element is motion-coupled with an end element which can be driven by a stroke movement comprising a vertical stroke and a horizontal stroke, and with a position measuring device for determining the position of the end element, wherein the position measuring device has a first position measuring unit for determining the position of the end element during the vertical stroke and a second position measuring unit for determining the position of the end element during the horizontal stroke, and wherein the control device is designed such that actual positions can be transmitted to the position measuring device and position control based on the actual position signal acquired by the position measuring device can be carried out.

A key aspect of the invention is that the position measurement or displacement measurement is divided into a vertical and a horizontal displacement measurement. This enables position control for both the vertical and the horizontal parts of the lifting movement.

In a particularly preferred manner, the end member first performs a vertical stroke and then a horizontal stroke. The horizontal stroke is particularly preferably initiated when the end member reaches a vertical end position during the vertical stroke. Alternatively, it is of course also conceivable that the end member first performs a horizontal stroke. performs a vertical movement stroke and then a vertical movement stroke.

In a particularly preferred manner, the position of a first actuator element of a first pneumatic actuator is measured by means of the first position measuring unit to determine the position of the end element during the vertical stroke.

Advantageously, the end element is motion-coupled with the actuator element of the first pneumatic actuator, so that the position of the end element can be determined by measuring the actual position of the actuator element, since the distance between the actuator element and the end element is known. Advantageously, the position of the first actuator element is continuously measured over its entire travel distance.

In a further development of the invention, the position of the end element during the horizontal stroke is determined by means of the second position measuring unit by measuring the position of a second actuator element of a second pneumatic actuator responsible for the horizontal stroke, which is coupled to the end element's movement. Here, too, the position of the end element can be deduced by measuring the actual position of the second actuator element of the second pneumatic actuator.

Alternatively, to determine the position of the end element during the horizontal stroke, the second position measuring unit could measure the position of a cam follower or a guide cam of a cam guide responsible for the horizontal stroke, which is motion-coupled with the end element and located in the first pneumatic actuator. Advantageously, the cam follower is located on the pneumatic actuator and the guide cam on a peripheral component. Advantageously, the position is measured continuously over the travel path of the cam follower or guide cam.

In a further development of the invention, the actual pressure in a pressure chamber of the first pneumatic actuator and/or in a pressure chamber of the second pneumatic actuator is measured and provided as an actual pressure signal to the control device.

In a further development of the invention, the pneumatic system has a slide valve, wherein the slide valve has an end element in the form of a valve element which is coupled to the first actuator element of the pneumatic actuator and is moved along with the actuator element, and wherein the slide valve has an opening for the passage of a wafer which can be opened or closed by the valve element.

In the case of the end element being designed as a valve element, it is therefore possible for the valve element to first be moved towards the opening with a vertical stroke and then subsequently moved into the closed position with a horizontal stroke, in which the valve element is fluid-tight against the opening. Advantageously, two pneumatic actuators are provided, one of which, equipped with a first actuator element, is responsible for the vertical stroke, and the other, equipped with a second actuator element, is responsible for the horizontal stroke of the end element, which is coupled to both the first and second actuator elements.

It is possible that the second actuator is arranged on the first actuator element and is moved along with it during the vertical stroke, with the end element being connected to the second actuator element of the second actuator and being movable relative to the first actuator element during the horizontal stroke.

Alternatively, it is possible that the second actuator is assigned to the first actuator and remains stationary during the vertical stroke, whereby the second actuator element of the second actuator can initiate a positioning movement of the first actuator, which can be converted into the horizontal stroke of the end element.

Advantageously, the positioning movement is a pivoting movement of the first actuator about a pivot axis. The pivot axis can thus divide the first actuator into a first lever arm and a second lever arm, with the first lever arm advantageously extending from the interface of the second actuator to the pivot axis and the second lever arm from the pivot axis to the end link.

In a further development of the invention, a single pneumatic actuator is provided, namely the first pneumatic actuator, to which a cam guide is assigned. This cam guide includes a cam follower and a guide cam associated with the cam follower, which are movable relative to each other and thereby produce the horizontal stroke. Advantageously, the cam follower is located on the pneumatic actuator.

Preferred embodiments of the invention are shown in the accompanying drawing and are explained in more detail below.

• 1 eine schematische Darstellung eines ersten Ausführungsbeispiels des erfindungsgemäßen pneumatischen Systems mit dem das erfindungsgemäße Verfahren durchführbar ist,
• 2 ein Blockdiagramm des erfindungsgemäßen Verfahrens zum Betrieb eines pneumatischen Systems für die Industrieautomation,
• 3 eine schematische Darstellung einer Wafer-Bearbeitungsanlage, die mehrere pneumatische Systeme gemäß 1 aufweist,
• 4 eine schematische Darstellung eines Teils des pneumatischen Systems von 1, wobei hier ein zweites Ausführungsbeispiel des pneumatischen Systems gezeigt ist, mit einer Ausführungsform eines Schieberventils, das in sich in einer deaktivierten Stellung (links), in einer teilaktivierten Stellung (Mitte) und einer aktivierten Stellung (rechts) befindet,
• 5 eine schematische Darstellung eines Teils des pneumatischen Systems von 1, wobei ein drittes Ausführungsbeispiel des erfindungsgemäßen pneumatischen Systems gezeigt ist, mit einem Schieberventil, das sich in einer deaktivierten Stellung (links)s, einer teilaktivierten Stellung (Mitte) und einer aktivierten Stellung (rechts) befindet,
• 6 eine schematische Darstellung eines Teils des pneumatischen Systems von 1, wobei ein viertes Ausführungsbeispiel des pneumatischen Systems gezeigt, mit einem Schieberventil, das sich in einer deaktivierten Stellung (links), einer teildeaktivierten Stellung (Mitte) und einer aktivierten Stellung (rechts) befindet.

The drawings show:

• 1 a schematic representation of a first embodiment of the pneumatic system according to the invention with which the method according to the invention can be carried out,
• 2 a block diagram of the inventive method for operating a pneumatic system for industrial automation,
• 3 a schematic representation of a wafer processing plant which incorporates several pneumatic systems according to 1 exhibits
• 4 a schematic representation of part of the pneumatic system of 1 , where a second embodiment of the pneumatic system is shown here, with an embodiment of a slide valve which is in a deactivated position (left), in a partially activated position (center) and in an activated position (right),
• 5 a schematic representation of part of the pneumatic system of 1 , wherein a third embodiment of the pneumatic system according to the invention is shown, with a slide valve that is in a deactivated position (left), a partially activated position (middle) and an activated position (right),
• 6 a schematic representation of part of the pneumatic system of 1 , wherein a fourth embodiment of the pneumatic system is shown, with a slide valve that is in a deactivated position (left), a partially deactivated position (center) and an activated position (right).

The 1 and 5 Figure 1 shows a first embodiment of the pneumatic system 11 according to the invention, which is shown and described here as an example for use in a wafer processing system 12. Of course, it is also possible to use the pneumatic system 11 in other areas of industrial automation. Its use in a wafer processing system 12 is therefore purely exemplary.

As particularly in 1 As shown, the pneumatic system has a control device 13 to which at least one pneumatic actuator 14 is assigned.

The construction of such a wafer processing system 12 is described in the 3 Shown purely schematically and as an example.

The wafer processing plant 12 has a distribution room 15 and several processing rooms 16 grouped around the distribution room 15, in each of which different processing processes take place on the wafers to be processed there.

In the distribution room, which is located in the 3 In a top view shown and having a horizontal plane formed by the x-axis direction 17 and the y-axis direction 18 of a Cartesian coordinate system spanned by three coordinates x, y, z, there is usually a handling unit, for example in the form of a robot, which places wafers to be processed into the adjacent associated processing rooms 16 and ejects processed wafers from the processing rooms 16.

Between the distribution room and the adjacent processing rooms are passageways, each equipped with 20 gate valves, such as those found, for example, in the 1.4 to 6 are shown, are assigned.

As particularly in 1 As shown, the processing area 16 has an exemplary rectangular basic shape and extends in a vertical direction, which can also be called the z-axis direction 19, in a transverse direction perpendicular to the vertical direction, which can also be called the x-axis direction 17 and in a horizontal direction, which can also be called the y-axis direction 18.

The machining chamber 16 has a machining chamber opening 21, which can be closed by means of the slide valve 20 to seal the machining chamber from the environment. The pressure in the machining chamber 16 is typically below atmospheric pressure.

As further in 1 As shown, the slide valve 20 has a valve housing 22 in which at least one opening 23 is formed for the passage of the wafer. Optionally, the valve housing 22 can also be integrally connected to the housing of the processing chamber 16, so that the processing chamber opening 21 corresponds to the opening 23. In the example shown, however, the valve housing 22 is an add-on component, and the opening 23 of the valve housing 22 of the slide valve is aligned with the processing chamber opening 21.

If necessary, the valve housing 22 may have a further opening 24, in particular assigned to the distribution chamber 15, which is aligned with the first opening 23.

A key element of the slide valve 20 is at least one pneumatic actuator 14, which could therefore also be referred to as a valve drive. In all the embodiments described below, the at least one pneumatic actuator 14 is shown by way of example in the form of a double-acting pneumatic cylinder.

As in particular according to the first embodiment of the 1 and 5 As an example, two pneumatic actuators 14a, 14b are provided, of which the first pneumatic actuator 14a is for a vertical stroke h _z ( 1 ) and the second pneumatic actuator 14b for the horizontal stroke h _x ( 2 are responsible.

Since the vertical stroke h_{_z} is generally significantly larger than the horizontal stroke h_{_z,} the dimensions of the two actuators 14a and 14b also differ. In the example shown, the first actuator 14a is therefore considerably larger and thus more powerful than the second actuator 14b. However, the basic design of the two actuators 14a and 14b is essentially identical.

The two actuators 14a, 14b therefore each have a cylinder housing 26a, 26b in which an actuator element 27a, 27b in the form of a piston is movably guided.

The respective actuator element 27a, 27b divides the interior 28 of the cylinder housing 26a, 26b into two pressure chambers 29a, 29b, which can alternatively also be referred to as working chambers. Pressure fluid in the form of compressed air can be selectively supplied to or discharged from the pressure chambers 29a, 29b in order to move the actuator element 27a, 27b from a first end position 30 to a second end position 31 and vice versa, from the second end position 31 to the first end position 30. The actuator elements 27a, 27b, which are designed as pistons according to the illustrated embodiment, are each connected to a piston rod 32a, 32b extending from the cylinder housing 26a, 26b. The first piston rod 32a, which is connected to the first actuator element 27a of the first actuator 14a, has an end element 33 in the form of a valve element attached to its free end. In the example shown, the valve element is designed as a sliding element.

The end member 33, i.e. the valve member in the form of the slide element, is assigned in the example shown to the first opening 23, which can be selectively opened or closed with the end member 33, whereby the opening and closing movement of the end member 33 is effected by the interaction of the two actuators 14a, 14b as a result of the pressurization of one or the other pressure chamber 28a, 29b.

To ensure the tightest possible closure of the first opening 23, the valve element has a circumferential, in particular rubber-elastic, sealing element 34 on its side facing the opening 23.

As already mentioned, according to the first embodiment, which is in the 1 and 5 The figure shows two pneumatic actuators 14a and 14b. The end member 33 is attached to the free end of the first piston rod 32a, which is connected to the first actuator element 27a of the first pneumatic actuator 14a, while the second piston rod 32b of the second pneumatic actuator 14b has no end member.

As already mentioned, the first actuator 14a is responsible for the vertical stroke _hz . The first actuator element 27a of the first actuator 14a is movable between the first end position 30, which in the example shown represents a lower end position, and the second end position 31 in the cylinder housing 26a. This allows the coupled piston rod 32a, and thus also the end element 33, to be driven to a vertical stroke _hz during the movement between the two end positions 30 and 31. The end element 33, in the form of the valve element, is moved between a ready position 35 with the piston rod retracted and an intermediate position 36 with the piston rod extended. In the intermediate position 36, the valve element is already positioned in the area of the opening 23 by the vertical stroke _hz , but is not yet in contact with the opening 23, so the opening 23 is not yet closed.

The end element 33, i.e., the valve element designed as a sliding element, can be moved from the intermediate position 36 to a closed position 37 by means of the horizontal stroke h _x generated by the second actuator 14b.

As exemplified in 1 and also in 5 As shown, the second actuator 14b is arranged next to the first actuator 14 and is stationary. The stroke movement of the second actuator element 27b of the second actuator 14 occurs in the x-axis direction 17, whereby the coupled piston rod 32b also extends out of the cylinder housing 26b along the x-axis direction 17. The second piston rod 32b faces the first cylinder housing 26a of the first pneumatic actuator 14a.

As further in 1 and also in 5 As shown, the first actuator 14a is pivotally mounted about a pivot axis 38. In the example shown, the first cylinder housing 26a of the first pneumatic actuator 14a is pivotally mounted about the pivot axis 38. The second actuator element 27a of the second actuator is also mounted between The first actuator 14a is movable between a first end position (not shown) and a second end position (not shown) in the associated cylinder housing 26b along the x-axis direction 17, with the movement in the example shown being from right to left, i.e., the first end position is on the right and the second end position is on the left. As already mentioned, the second piston rod 32b is extended and comes into contact with the outer shell of the first cylinder housing 26a, which is caused to pivot about the pivot axis 38, in the example shown in a clockwise direction. This pivot movement causes the end member 33, or valve member, to move from the intermediate position 36 to the closed position 37. The pivot axis 38 divides the first actuator 14a into a first lever arm 39a and a second lever arm 39b. The first lever arm 39a extends from the contact point between the second piston rod 32b and the first cylinder housing 26a to the pivot axis 38, and the second lever arm extends from the pivot axis 38 to the extended piston rod and the end member 33 attached there. Due to the lever ratio, a relatively small second pneumatic actuator 14b, which operates with low pressure fluid consumption, can be used here.

The pneumatic system 11 further comprises a position measuring device 40 for measuring the position of the actuator element 27 during its movement, i.e., for example, the position of the piston in the cylinder housing 26. The position measuring device 40 has a first position measuring unit 41a for determining the position of the end element 33 during the vertical stroke _hz and a second position measuring unit 41b for determining the position of the end element 33 during the horizontal stroke _hx .

As particularly in 1 As shown, the control device 13 is designed such that actual positions can be transmitted from the position measuring device 40, i.e. from the position measuring units 41a, 41b, and position control can be carried out on the basis of the actual position signal recorded by the position measuring device 40.

As further in 1 and also in 5 As shown, to determine the position of the end member 33 during the vertical stroke _hz, the position of the first actuator member 27a of the first pneumatic actuator 14 is measured using the first position measuring unit 41a, and to determine the position of the end member during the horizontal stroke _hx , the position of the second actuator member 27b of the second pneumatic actuator 14b, which is coupled to the end member 33, is measured using the second position measuring unit 41b. The coupling of the second actuator member 27b with the end member 33, i.e., the valve member in the form of the slide element, is achieved via the previously described contact between the first cylinder housing 26a and the second actuator member 27b.

Advantageously, the position measuring units are designed as continuous position measuring units 41a, 41b. In this specific example, the position of the first actuator element can therefore be continuously determined during the vertical stroke _hz between the two end positions 30, 31. The same applies to the second actuator 14b. Here, position determination is possible over the entire travel distance of the horizontal stroke _hx between the two end positions of the second actuator element 27b. Alternatively, it would be conceivable, for example, to provide position determinations only in the area of the two end positions instead of determining the position of the first actuator element over the entire travel distance, with no position determination taking place between the two end positions. Since the travel distance of the second actuator element is very small anyway, this alternative is not an option for the second pneumatic actuator.

The pneumatic system 11 further comprises a pressure measuring device 42 for measuring the actual pressure in at least one pressure chamber 29a, 29b of the at least one pneumatic actuator 14a, 14b and transmitting the actual pressure in the form of an actual pressure signal to the control device 13. In the example shown, the first actuator 14a is assigned a pressure measuring device 42 with two pressure measuring units 43a, 43b, which are preferably designed as pressure sensors. The second actuator 14b can also be assigned a pressure measuring device, although this is not shown in the drawings.

It is possible that the pressure sensors are each assigned to pressure chambers 29a and 29b, for example, installed in the respective pressure chambers 29a and 29b. However, it is preferred that the pressure measuring device 42 is integrated into a control valve assembly (not shown), which in turn comprises several control valves for the fluidic actuation of the associated pneumatic actuator 14a and 14b. Advantageously, the control valves are each designed as proportional valves that exhibit the required control accuracy. Piezoelectric valves, in particular, are especially suitable as proportional valves. Typically, at least one piezoelectric element is used as the valve element.

The control valve assembly is particularly preferably designed as a valve manifold or valve battery, with a one-piece or multi-piece base. plate which acts as a fluid distributor and has on its upper side a plurality of mounting positions for control valves or other functional units, in particular disc-shaped ones, for example safety modules, silencers or the like.

The control valve assembly, in particular in the form of a valve manifold or valve bank, can include a part of the control device 13 in the form of a pressure regulator 13b. The pressure regulator 13b can, for example, have several pressure sensors arranged in associated channels, for example on a printed circuit board.

One of the main tasks of the control unit 13, whose control scheme is in 12 As shown by way of example, the purpose is to prevent a hard stop when the valve element moves into the closed position 38. This prevents vibrations from occurring when moving into the closed position, but also when moving into the intermediate position 36, which could adversely affect wafer production, for example by stirring up particles and getting onto the wafer surface. The control device 13 can comprise a position control device 13a and a pressure control device 13b.

The control valve assembly, in particular a valve manifold or valve bank, can have a common controller for the position control device and the pressure control device. However, the controller can also be separate from the control valve assembly and connected to it via a signal interface.

The communication system underlying the signal connection can preferably be a communication system from the group OPC UA (Open Platform Communication Unified Architecture), OPC UA over TSN (Time-sensitive Networking), bus communication system, IO Link, whereby a power supply can also be enabled via the signal connection.

• Zunächst befindet sich der erste Aktor 14a, also der doppelt wirkende Pneumatikzylinder in seinem deaktivierten Zustand. Das Endglied beziehungsweise Ventilglied befindet sich in der Bereitschaftsposition 35, das heißt die Öffnung 23 in die Bearbeitungskammer 16 ist offen. Das erste Aktorglied 27a, also der Kolben befindet sich in seiner ersten Endlage 30, bei der sich im gezeigten Beispielsfall um die untere Endlage 30 handelt.

The procedure for operating the pneumatic system according to the first embodiment could proceed as follows:

• Initially, the first actuator 14a, i.e., the double-acting pneumatic cylinder, is in its deactivated state. The end element, or valve element, is in the ready position 35, meaning the opening 23 into the machining chamber 16 is open. The first actuator element 27a, i.e., the piston, is in its first end position 30, which in the example shown is the lower end position 30.

After loading the processing chamber 16, it is necessary to seal the opening 23 fluid-tight with the valve element.

Advantageously, a trajectory or path curve is specified for the control device 13, or the control device 13 is used based on position reference values (X _Ref , ). 2 ) calculates a trajectory that specifies how the first actuator element 27a should move between the first end position 30 and the second end position 31.

The specified target positions of the actuator element 27a are converted into pressure signals and accordingly the two pressure chambers 29a, 29b are pressurized with compressed air, whereby of course for the movement from the first end position 30 to the second end position 31 a higher pressure must prevail in the first pressure chamber 29a than in the second pressure chamber 29b.

After the first actuator element starts moving, its position is continuously measured over its entire travel path, which is the vertical stroke for the end element or valve element, by the first position measuring unit 41a. This means that actual position values are determined and transmitted to the control unit 13 in the form of actual position signals. Simultaneously, a subordinate pressure control takes place; that is, the actual pressures in the pressure chambers 29a and 29b are measured and also transmitted to the control unit 13 in the form of actual pressure signals.

If the actual position deviates from the target position, adjustments are made to minimize these deviations. This means the pressure in pressure chambers 29a and 29b is changed. Simultaneously, the subordinate pressure control system also determines the deviation of the actual pressure from the target pressure and compensates accordingly.

In the example shown, the comparison of the actual position with the target position is carried out continuously during the vertical movement stroke _hz , whereby measurements are taken continuously and the actual-target comparison is performed within very small time intervals.

The position control during the vertical stroke _hz ensures that the first actuator element 27a moves out of the first end position 30 and moves towards the second end position 31 based on the predefined trajectory. It is advantageous to position the actuator element 27a relative to to move quickly towards the second end position 31, whereby braking must be carried out in good time before reaching the second end position in order to prevent a hard impact.

In the example shown, the retraction of the first actuator element into the second end position 31 corresponds to the movement of the end element 33 into the intermediate position 37. Once the second end position 31 is reached, i.e., the intermediate position 36 of the end element is approached, the horizontal stroke is then initiated on the end element 33 in the form of the valve element, which ensures that the end element 33 moves from the intermediate position 36 to the closed position 37. For this purpose, the second actuator 14b is activated, so that the second actuator element moves from its first end position 30 to the left into its second end position 31. During this movement, the second piston rod 32b is extended and comes into contact with the first cylinder housing 26a, which is thereby caused to pivot about the pivot axis 38 in a clockwise direction. Here too, position control can be achieved via the travel distance or the horizontal stroke _hx , by measuring the actual positions of the second actuator element over the entire travel distance and transmitting them to the control unit 13, where an actual-target comparison takes place analogously to the vertical stroke _hz . Here too, it is important to slow down the retraction of the second actuator element 27b into its second end position 31, so that the end element 33, in the form of the valve element, does not come into contact with the wall section surrounding the opening 23.

The 4 Figure 11 shows a second embodiment of the pneumatic system 11. Here too, as in the first embodiment described above, two pneumatic actuators 14a, 14b are provided, wherein the first pneumatic actuator 14a is responsible for the vertical stroke _hz and the second pneumatic actuator 14b is responsible for the horizontal stroke _hx .

In contrast to the first embodiment described above, the second actuator 14b is not arranged next to the first actuator 14a, but is attached to the first piston rod 32a of the first actuator 14a. The second actuator 14b is therefore moved along with the first piston rod 32b. Another difference is that the end member 33, i.e., the valve member in the form of the slide element, is not attached to the first piston rod 32a, but to the second piston rod 32b of the second actuator 14b.

Here too, the vertical movement stroke is executed first to move the end element 33 from the ready position 35 to the intermediate position 36. The control is analogous to the control in the first embodiment described above.

Once the intermediate position 36 is reached, the horizontal stroke h _x is triggered, so that the second actuator element 27b, i.e. the piston in the second double-acting pneumatic cylinder, moves from its first end position 30 to its second end position 31 and the second piston rod with the coupled valve element is moved from the intermediate position 36 to the closed position 37.

The 6 Figure 11 shows a third embodiment of the pneumatic system 11 according to the invention. This third embodiment differs significantly from the first two embodiments described above, as it uses only a single pneumatic actuator 14. The horizontal stroke _hx following the vertical stroke _hz is generated by a positive control of the first pneumatic actuator with respect to its position relative to the opening 23 to be closed. A cam guide 44 is associated with the pneumatic actuator 14. This cam guide includes a cam follower 45 and a guide cam 46 associated with the cam follower 45. These cams are movable relative to each other and thereby produce the horizontal stroke _hx .

Advantageously, the cam follower 45 is arranged in the form of a pin or stud on the cylinder housing 26 and protrudes outwards from it.

The guide cam 46 is located on a peripheral component. The guide cam 46 has a guide track 47 on which the cam follower 45 can slide. The guide track 47 is inclined to both the x-axis direction 17 and the z-axis direction 19. The angle of inclination between the horizontal direction (i.e., the x-axis direction 17) and the guide track 47 is in the range of 45° to 80°.

It should also be mentioned that the cylinder housing 26 is supported against the base by means of a spring element 48, the spring force of which is a compression spring ensuring that the cylinder housing 26 and thus the first actuator 14 is pushed upwards away from the base, so that the cam follower 45 arranged on the cylinder housing 26 rests in the upper area of the guide track 47.

As particularly in 6 As shown, a pivot axis element 49, for example in the form of a disc or ball, is arranged on the piston rod 32, which is coupled to the actuator element 27 in the form of the piston, and which pivots during the vertical stroke h _z. is moved along with the piston rod 32. At one end of the piston rod 32, the end member 33, in the form of the valve member, is arranged. A characteristic feature of this embodiment is that, when the piston rod 32 extends, the pivot axis element 49 encounters a pivot bearing 50 arranged on the valve housing 22. This, in combination with the cam guide 44, triggers a pivoting movement of the actuator 14 about a pivot axis 51, which is located in the area of the pivot axis element 49 abutting the pivot bearing 15.

• Zunächst befindet sich das Aktorglied 27 in seiner unteren ersten Endlage 30. Das Federelement 48 drückt das Zylindergehäuse 26 nach oben. Der Kulissenfolger 45 befindet sich am oberen Ende der Führungsbahn 47.

The functionality and regulation of the third embodiment can be summarized as follows:

• Initially, the actuator element 27 is in its lower first end position 30. The spring element 48 pushes the cylinder housing 26 upwards. The cam follower 45 is located at the upper end of the guide track 47.

By pressurizing the lower pressure chamber 29a according to the predetermined trajectory, the piston moves upwards from its first end position 30 towards the second end position 31. Position control takes place analogously to the first and second embodiments described above. The vertical stroke _hz causes the piston rod 32 to extend and the pivot bearing element 49 on the piston rod to move upwards towards the pivot bearing 50. During the vertical stroke _hz, the pivot bearing element 49 on the piston rod 32 then engages the pivot bearing 50 without the piston or the actuator element 27 having previously reached its second, upper end position 31. The impact of the pivot bearing element on the pivot bearing causes the cylinder housing 26 of the actuator 14 to pivot clockwise. This occurs because the cam follower 45 slides downwards on the inclined guide track 47, tensioning the spring element and extending the piston rod further out of the cylinder housing. Care must be taken to ensure that the retraction of the pivot bearing element 49 into the pivot bearing 50 does not result in a hard stop. This is achieved by braking the actuator element 27 in a timely manner. The horizontal movement h_x initiated after the completion of the vertical stroke _h _{_z} by the pivot bearing element 49 striking the pivot bearing 15 is monitored by a position measuring unit 41b arranged on the guide cam 46. This means that, as with the position control for the vertical stroke described above, position control for the horizontal stroke h_{_x} can also be implemented there.

Claims (16)

Method for operating a pneumatic system (11) for industrial automation, comprising at least one pneumatic actuator (14; 14a, 14b) and a control device (13) for controlling a movement of an actuator element (27; 27a, 27b) of the at least one pneumatic actuator (14; 14a, 14b) from a first end position (30) to a second end position (31) and/or from the second end position (31) to the first end position (30), wherein the actuator element (27; 27a, 27b) is motion-coupled with an end element (33) which can be driven by a stroke movement comprising a vertical stroke (h _{_z} ) and a horizontal stroke (h _{_x}), comprising the steps: - Determining a position of the end element (33) by means of a position measuring device (40), wherein by means of a first The position measuring unit (41a) determines the position of the end member (33) during the vertical movement stroke (h _z ) and, by means of a second position measuring unit (41b), the position of the end member (33) during the horizontal movement stroke (h _x ) is determined, - providing the determined position as an actual position signal to the control device (13), - carrying out a position control based on the actual position signal acquired by the position measuring device (40). Procedure according to Claim 1 , characterized in that the end member (33) first performs a vertical movement stroke (h _z ) and subsequently a horizontal movement stroke (h _x ), wherein preferably the horizontal movement stroke (h _x ) is triggered when the end member (33) has reached a vertical end position during the vertical movement stroke (h _z ). Procedure according to Claim 1 or 2 , characterized in that , to determine the position of the end member (33) during the vertical stroke (h _z ) by means of the first position measuring unit (41a), the position of a first actuator member (27a) of a first pneumatic actuator (14a) is measured, preferably with a continuous position measurement over the travel path of the first actuator member (14a). Method according to one of the preceding claims, characterized in that , to determine the position of the end member (33) during the horizontal stroke (h _x ), the position of a second actuator member (27b) of a second pneumatic actuator (14b) responsible for the horizontal stroke, which is coupled to the end member (33) in motion, is measured by means of the second position measuring unit (41b), wherein preferably a continuous position measurement sung via the travel path of the second actuator element (27b). Procedure according to one of the Claims 1 or 2 , characterized in that , to determine the position of the end member (33) during the horizontal movement stroke (h _x ) by means of the second position measuring unit (41b), the position of a cam follower (45) or a guide cam (46) of a cam guide (44) responsible for the horizontal movement stroke (h _x ) is measured, which is coupled to the movement of the end member (33) and arranged on the first pneumatic actuator (14a), wherein preferably a continuous position measurement is carried out over the travel path of the cam follower (45) or the guide cam (46). Method according to one of the preceding claims, characterized in that the actual pressure in a pressure chamber ((29a, 29b) of the first pneumatic actuator (14a) and/or pressure chamber of the second pneumatic actuator (14b) is measured and the actual pressure is provided as an actual pressure signal to the control device (13). Method according to one of the preceding claims, characterized in that the pneumatic system (11) has a slide valve (20), wherein the slide valve (20) has an end member (33) in the form of a valve member which is coupled to the actuator member (27; 27a, 27b) of the first pneumatic actuator (14; 14a, 14b) in terms of movement and is moved along with the actuator member (27; 27a, 27b), and wherein the slide valve (20) has an opening for the passage of a wafer which can be opened or closed by the valve member. Procedure that the first actuator (14a) and/or second actuator (14b) is a single- or double-acting pneumatic cylinder. A pneumatic system for industrial automation, comprising at least one pneumatic actuator with an actuator element, a control device for controlling a movement of the actuator element from a first end position to a second end position and/or from the second end position to the first end position, wherein the actuator element is motion-coupled with an end element that can be driven by a stroke movement comprising a vertical stroke and a horizontal stroke, and with a position measuring device for determining the position of the end element, wherein the position measuring device comprises a first position measuring unit for determining the position of the end element during the vertical stroke and a second position measuring unit for determining the position of the end element during the horizontal stroke, and wherein the control device is designed such that actual positions can be transmitted from the position measuring device and position control can be carried out based on the actual position signal acquired by the position measuring device. that at least two pneumatic actuators are provided, of which a first pneumatic actuator equipped with a first actuator element is responsible for the vertical stroke and a second pneumatic drive equipped with a second actuator element is responsible for the horizontal stroke of the end element, which is coupled to both the first actuator element and the second actuator element. that the second actuator is arranged on the first actuator element and is moved along with it during the vertical stroke, wherein the end element is connected to the second actuator element of the second actuator and is movable relative to the first actuator element during the horizontal stroke. that the second actuator is assigned to the first actuator and is stationary during the vertical stroke, whereby the second actuator element of the second actuator can be used to initiate a positioning movement of the first actuator, which can be converted into the horizontal stroke of the end element. that the positioning movement is a pivoting movement of the first actuator around a pivoting axis. that a single pneumatic actuator, namely the first pneumatic actuator, is provided, to which a cam guide is assigned, which has a cam follower and a guide cam assigned to the cam follower, which are movable relative to each other and thereby cause the horizontal stroke, wherein preferably the cam follower is arranged on the pneumatic actuator. further comprising a slide valve wherein the slide valve has an end member in the form of a valve member coupled to the first actuator member of the first pneumatic actuator and has an opening that can be closed by the valve member. that the first actuator and/or the second actuator is designed as a single- or double-acting pneumatic cylinder.