EP1882102B1 - Fluid operated drive and method for control thereof - Google Patents

Abstract

The invention relates to a fluid-operated drive (1) and a method for control thereof with components which may be adjusted relative to each other, of which one component may be displaced in a first and an opposing second movement direction by means of a switch element (10, 11). In a first displacement phase for the component, a first measured signal (S<SUB>1</SUB>) is recorded shortly before reaching the approached end position at a time (T<SUB>1</SUB>) by a switch flag arrangement and a second measured signal (S<SUB>2</SUB>) recorded at a later time (T<SUB>2</SUB>). A time span (t<SUB>1Ist</SUB>) is subsequently determined by the controller (13) from the time difference between the measured signals (S<SUB>1</SUB>, S<SUB>2</SUB>) and used by a regulator for a soft approach to the end position from a variance comparison between a fixed time span (t<SUB>1Soll</SUB>) and the determined time span (t<SUB>1Ist</SUB>) to determine a parameter for at least one of two different serial switch times for the switch element (10, 11). A switch time for the switch element (10, 11) in the further displacement phase subsequent to and in the same direction as the first displacement phase is set by means of the parameter.

Description

The invention relates to a fluidically actuated drive and a method for controlling the same, as described in the preambles of claims 1, 16, 22 and 30.

From the DE 44 10 103 C1 is a fluidically actuated drive or a method for controlling the same with an electronic control device and actuated by this switching elements known. The drive comprises relatively adjustable components, of which a component via the first switching element in a first direction of movement and the second switching element in one of the first direction of movement opposite, second direction of movement between end positions can be moved. In addition, the drive is provided in its end positions with shock absorbers, which absorb the impact energy of the accumulating on this component. In order to achieve a particularly smooth approach to an end position of the component, the controller is provided with a counter-pulse module which can be controlled via a Vorpositioniersensor which is associated with at least one direction of movement of the component. The counterpulse module causes a temporally adjustable reversal of the two switching elements, so that the component of the drive applied immediately before reaching its approaching end position in the direction opposite to the direction of the pressure medium over a fixed period of time and thereby a braking effect is generated. In a temporally subsequent to the reversal period of time, both the first and the second switching element in the sense of a caster are energized simultaneously. As a result, the drive is acted upon on both sides with system pressure and the component due to its inertia further driven at low speed in the direction of the end position. Thereafter, the originally active switching element is energized again and moves the component reliably in the end position. The reversal of the switching elements, the setting of the duration of the counter-pulse and the specification of the follow-up time via manually operated actuators, such as potentiometers. The fixed times via the potentiometers, however, lead to disruptions in the event of changed operating conditions such as pressure fluctuations, changes in the load or friction, which can even cause damage to the drive or to a machine system. In addition, in this known drive an increased circuit complexity, since a Vorpositioniersensor and a limit sensor is required for each direction of movement.

A method for controlling a fluidic drive as well as a device with a fluidically actuated drive is also known from DE 197 21 632 C2 known. The drive is formed by a lifting cylinder in which an actuating piston is guided with a piston rod. The piston rod is fixedly mounted via a fixed bearing, so that the lifting cylinder forms the moving component of the drive. The lifting cylinder is connected to a 5/3-way valve, which can be controlled by means of two electromagnetic control magnets and with which pressure chambers of the lifting cylinder are mutually acted upon by system pressure. The control magnets are connected to an electronic control device which in turn receives control signals from sensors that can be switched electronically via switching lugs and, depending on this, actuates the 5/3-way valve and thus the movement of the lifting cylinder. In the movement phase of the lifting cylinder, a first measuring signal S ₀ is generated at a time T ₀ and a second measuring signal S ₁ at a later time T ₁ lying in the movement phase of the lifting cylinder and a time difference t ₁ from this, taking into account the actual movement parameters of the lifting cylinder calculated. For soft starting at least one of the end positions of the lifting cylinder is calculated from this time difference t _1, a time t ₂ for the beginning of a braking phase at a time T ₂ and the duration of the braking phase t ₃ to a time T ₃ , wherein the control device for braking the Lifting cylinder to the 5/3-way valve outputs a brake signal for the beginning and for the end of the braking phase. According to this prior art, it is essential that the first measurement signal S ₀ detected immediately at the beginning of the movement of the lifting cylinder from its end position and the second measurement signal S ₁ in the movement phase sufficiently before the occurrence of a switching flag in the effective range of a sensor associated with the end position become. This proves to be a disadvantage since the state of motion over the movement phase between the time T _{1 of} the detection of the second measurement signal S ₁ and that time in which the lifting cylinder actually reaches its end position to be approached is disregarded, whereby based on the time difference t ₁ between the first and second measurement signal S _0, S ₁ calculated braking phase t ₃ regardless of the varying operating conditions such as pressure fluctuations, changes in load or friction is determined, and in spite of the initiated braking phase a controlled start-up or a damped positioning of the lifting cylinder in the end positions can not be guaranteed.

The object of the invention is to provide a fluidically actuated drive and a method for controlling the same, in which the adjustable means of pressure medium component of Drive even with changed operating and environmental conditions, the end position particularly gently anfährt.

The object of the invention is achieved by the measures and features of claims 1 and 16. The two measuring signals are triggered only shortly before reaching the end position to be approached, and the switching elements are actuated by the control device as late as possible with respect to the movement phase of the component acted upon by the pressure medium. As a result, only a very short braking phase is required in relation to the movement phase of the component, which is sufficient for the component to be gently positioned against the end position of the stationary component of the drive and braked for the shortest possible path, so that on the one hand the movement times of the component significantly shortened between the end positions and on the other hand optionally additionally used shock absorbers designed with less power reserve or even eliminated, which has a favorable effect on the size and price of the drive. In addition, it is advantageous that changes in operating and ambient conditions, which are caused for example by pressure fluctuations in the pressure medium, changes in the load to be manipulated or friction conditions, hardly affect the braking behavior of the component against the end position, since the calculation of the switching times of Switching elements and correction of at least one common switching time of the switching elements underlying movement speed is determined only just before reaching the end position to be approached, ie at a time in which the changes of operating and environmental conditions have the greatest effect and therefore on the in the vicinity of the to be approached end position prevailing motion state optimally coordinated correction of at least one common switching time of the switching elements can be made. In other words, the component is always decelerated to such an extent against the final position, as required by the current operating condition. In addition, it is advantageous that the pressure chambers alternately always with the system pressure (neglecting the friction losses) is applied, thus both the driving force on the component and the counterforce or braking force on the component corresponds to the maximum, which is beneficial to the movement times affects the component and a simple circuit construction of the fluid control of the drive allows, especially since additional throttle check valves can be omitted to adjust the braking behavior. Furthermore, it is advantageous that the use of the control system achieves an adaptive system behavior is set, especially since optimal operation of the drive independently and this can be maintained over the entire operating life.

Another advantage is the measure according to claim 2, since now by the controller from her vorgebaren, actual motion parameters, such as the mass to be moved, the operating conditions for the system pressure, the valve flow and the like., Taking into account the state of motion or the speed of movement Component, a counter control period is calculated, which defines the braking phase exactly and thus a particularly smooth approach to the end position is possible. In cooperation with the opposite and sudden pressurization of the pressure chambers in the switching times at the beginning and at the end of the braking phase, the demands made on the drive dynamics and ease of control can be optimally met, since the underlying the control drive on the one hand, the movement time for the Adjustment movement of the component between the end positions can be drastically reduced and on the other hand a conservation of the mechanical design of the drive is achieved.

An advantageous measure is described in claim 3, whereby an optimal timing between the time T ₁ , in which the first measurement signal S _{1 is} triggered, and the switching _times T _UZ1 , T _{UZ2 of} the switching element in compliance with the derived from the time t ₁ Counter control duration t _{GD is} reached, so that the positioning of the switching flags having control strips on the moving component and the sensors to each other is not critical.

According to claim 4, an advantageous measure for setting the counter-control period t _{GD is} described, which is easy to apply and by the beginning and end of the braking phase are defined exactly.

An advantageous measure is also described in claim 5, with which by setting the first switching time T _UZ1 the counter control period t _GD or the duration of the braking phase is specified. A calculation and adjustment of the end of the braking phase can be omitted, whereby the cycle time for the control process can be reduced. This control method is therefore ideal for drives with extremely low movement times.

The measure according to claim 6 is advantageous, since hereby the component arrives safely in its desired end position and the functionality of the drive is ensured. For this purpose, a renewed advance of the component in the direction of movement is exerted in the direction of its end position at the end of the braking phase for the second switching time at which the component already has an extremely low movement speed.

According to the measure according to claim 7, the movement time of the component can be optimized in the subsequent to the first movement phase with a first direction of movement, second movement phase with opposite direction of movement.

Also advantageous is the measure according to claim 8, which ensures that all calculations for the manipulated variables of the first and / or second switching time of the switching element within the time period t _{4 are} performed by the control device. This allows a highly reliable control of the drive, especially since the manipulated variables are already present in the same direction of movement clearly before the movement start of the next movement phase.

The measure according to claim 9 is advantageous, since in the temporal control of the switching element takes into account the system-induced inertia of the drive and the start time is advanced by the time t ₅ , so that the component is actually set in motion at the desired time. With this measure, the movement time of the component can be further optimized.

In accordance with the measure according to claim 10, the control device of the first drive is provided with the system inertia of the second drive taking into account time t ₅ , so that, for example, a feedback signal before reaching the end position of the component triggered by the first drive and the start time of the second drive is presented. Due to the leading feedback independent of the system inertia of the second drive, the associated switching element early on, so that the second drive starts at the same time as reaching the end position of the first drive with its movement. However, the acknowledgment signal does not necessarily have to be leading, ie it must be output to the control device or to the higher-level control before the end of the movement phase of the first drive. There are also conceivable applications in which the feedback signal is delivered simultaneously or after reaching the end position of the first drive. This is necessary, for example, if absolutely vibration-free positioning of the first drive in one of its end positions is necessary for a further operation on the second drive.

Another advantage is the monitoring of the signal waveform of the sensors and their evaluation, as described in claim 11.

By the measures according to claims 12 and 13, an impermissible state of movement of the component can be detected in a first movement phase and corrected in the subsequent movement phase by changing the counter-control period t _GD . According to claim 12 is recognized by the control device that the movement speed of the component is just before reaching its end position is too high and must be reduced taking into account the dynamic stress of the drive, for which the counter control period t _{GD is} increased. This ensures reliable operation over the entire service life of the drive. By contrast, it is recognized by the control device according to claim 13 that the speed of movement of the component is relatively low shortly before reaching its end position and can be selected higher, for which the Gegensteuerdauer t _GD reduced and the movement speed is increased so far that the movement time for the movement of the component is optimized between the end positions.

An advantageous measure is also described in claim 14, whereby a malfunction on the drive immediately recognized, evaluated and made visible to an operator.

Another advantage is the measure according to claim 15, whereby, for example, the function of a drive additionally used, mechanical shock absorber can be monitored and an impending failure of the shock absorber as an error message of an operator is announced. As a result, a malfunction of the drive due to malfunction, for example during a working process, such as a joining operation and the like, can be avoided.

An advantageous embodiment of the invention is described in claim 17, which allows reliable operation of the drive.

According to claim 18, the different evaluations, for example, the waveform of the sensors or the counter control period t _GD , an operator can be displayed and logged.

The development according to claim 19 is advantageous, since on the short path from the first control edges to the second control edge a change in the state of motion, in particular a strong fluctuations in the speed of movement of the component, will hardly occur and therefore the determined time t ₁ and the speed of movement represents a reliable parameter for setting the counter control period. The specified minimum width of the recess groove allows reliable detection of the control edges, by which the first and second measurement signal are triggered.

Also advantageous is the embodiment according to claim 20, whereby the wiring and tubing between the control device and the switching element and the pressure loss in the pressure lines between the switching element and the pressure chambers can be reduced, which has a positive effect on the time t ₅ . If the switching element is constructed on one of the components or integrated in one of the components, the pressure lines are formed by pressure medium channels, in particular inflow and outflow channels, which connect directly to the supply channels of the switching element and open into the pressure chambers, as described in US Pat WO 99/09462 A1 disclosed in detail and can also find applications in the drive according to the invention.

According to claim 21, any position can now be approached via the adjustment path of the movable component of the drive, for which only one or both hard stops and / or shock absorbers and / or a control bar and a sensor associated therewith must be adjusted. For example, a center position on the drive can now be approached smoothly.

However, the object of the invention is also achieved by the measures and features indicated in the characterizing part of claims 22 and 30. It is advantageous that, based on a predetermined movement time for the adjusting movement of the component between the end positions in both directions of movement an optimized as needed control of the drive made and the driving behavior of the component can be specified controlled. This allows the installer in the commissioning of the drive to specify the movement time so that the component is moved in crawl, which on the one hand possible damage to the drive due to incorrect programming or assembly can be prevented and on the other hand, the drive meets the increasing safety requirements. Especially in the commissioning of the drive, the fitter is in the effective range of the same and therefore there is a high risk potential, which can be almost completely turned off by the inventive measures. In addition, the drive is always driven with such a movement speed, as required by the current operating situation. Thus, unnecessary wear is avoided by unnecessary, low movement times, extends the maintenance intervals and increases the life of the drive. Furthermore, it is advantageous that an adaptive system behavior is achieved by the use of the control, especially since an optimal operating mode of the drive can be set independently and maintained over the entire service life. The drive according to the invention represents a good compromise between sufficiently high speed of movement and gentle operation, since the end position of the component can be approached particularly gently.

Also advantageous are the measures according to claims 23 and 24, as kept low by the pulsed operation of the energy requirement and a delay in the movement speed of the component is selectively adjusted until it reaches its end position.

According to the measure according to claim 25, a simple control of the drive is made possible.

The measure according to claim 26 is advantageous, since now influencing variables resulting in operation can be taken into account in a simple manner and the braking behavior of the component can be optimized even better.

An advantageous measure is also described in claim 27, since the last switching pulse and the Nachschaltimpuls overlap each other and a repeated reversal of the switching element can be omitted to hold the component in the end position. The holding force acting on the component ensures reliable positioning of the component in the end position. Is the drive equipped with a tool that has to be moved out of the end position, For example, a work process, such as a joining process, can be carried out absolutely reliably.

Of advantage are also the measures according to claims 28 and 29, as an excessive drop in speed is detected by the controller or the controller unit and after a predetermined period of time, the switching element again activated and the component is driven to move it to its end positions and Position against the end position. In particular, by the measure according to claim 29, the actual movement time of the component can be shortened.

An advantageous embodiment of the invention is described in claim 31, which allows reliable operation of the drive.

Finally, the embodiment according to claim 32 is also advantageous since at most necessary inputs of technical parameters can be carried out easily. Furthermore, error messages can be output in optical and / or acoustic representation. An error message can be triggered if, for example, even after the Nachschaltimpulses the component has not reached the end position and a predetermined by the control device or the higher-level control period has elapsed and a limit is exceeded. In this case, the error message may contain information about a technical defect on the drive or that a mounting part is clamped to the drive and thereby movement of the component is prevented.

The invention will be explained in more detail below with reference to the embodiments illustrated in the drawings.

Fig. 1

ein Blockschaltbild mit einer ersten Ausführung eines erfindungsgemäßen An- triebs in seiner rechten Ausgangslage, in schematischer Darstellung;

Fig. 1a

ein Ausschnitt des erfindungsgemäßen Antriebs nach Fig. 1 mit einer Steuerleiste, in vergrößerter und vereinfachter Darstellung;

Fig. 2

der Antrieb aus Fig. 1 in seiner linken Endlage;

Fig. 3

ein Blockschaltbild des Antriebs in seiner rechten Ausgangslage mit einer anderen Ausführung zu seiner fluidischen Ansteuerung, in vereinfachter Darstellung;

Fig. 4

der Antrieb nach Fig. 3 in seiner linken Endlage;

Fig. 5

ein Blockschaltbild mit einer anderen Ausführung des erfindungsgemäßen An- triebs in seiner rechten Ausgangslage;

Fig. 6

der Antrieb nach Fig. 5 in seiner linken Endlage;

Fig. 7

ein Handhabungssystem mit zwei miteinander gekoppelten Antrieben für recht- winkelig zueinander liegende Bewegungen, in schematischer Darstellung;

Fig. 8

ein Zeitdiagramm der Signalverläufe der Sensoren und der Schaltelemente für verschiedene Bewegungsphasen des Antriebs nach den Fig. 1, 2, 5 bis 7;

Fig. 9

ein Diagramm zur Erläuterung der vorteilhaften Wirkung des frühzeitigen Entlüf- tens der in der vorangegangen Bewegungsphase am Ende druckbeaufschlagten Druckkammer;

Fig. 10

ein Zeitdiagramm der Signalverläufe der Sensoren und des Schaltelementes für verschiedene Bewegungsphasen des Antriebs nach den Fig. 3 und 4 ;

Fig. 11

das erfindungsgemäße Verfahren zur Steuerung des fluidisch betätigten Antriebs in der Darstellung als Flussdiagramm;

Fig. 11a

ein Blockschaltbild zu dem in Fig. 11 in strichlierte Linien eingetragenen, ersten Regelkreis;

Fig. 11b

ein Blockschaltbild zu dem in Fig. 11 in strichlierte Linien eingetragenen, zweiten Regelkreis;

Fig. 12

das erfindungsgemäße Verfahren zur Steuerung des fluidisch betätigten Antriebs in modifizierter Ausführung, dargestellt als Flussdiagramm;

Fig. 12a

das Zeitdiagramm nach Fig. 8 mit dem Signalverlauf vom in der Zielendlage an- geordneten Sensor, der eine Rückprallbewegung des Bauteils an der Endlage er- fasst;

Fig. 12b

das Zeitdiagramm nach Fig. 8 mit dem Signalverlauf vom in der Zielendlage an- geordneten Sensor, der eine Pendelbewegung des Bauteils vor der Endlage erfasst;

Fig. 13

ein Blockschaltbild des Antriebs in seiner rechten Ausgangslage mit einer anderen Ausführung zu seiner erfindungsgemäßen Ansteuerung, in vereinfachter Darstel- lung;

Fig. 14

der Antrieb aus Fig. 13 in seiner linken Endlage;

Fig. 15

ein Zeitdiagramm der Signalverläufe der Sensoren und des Schaltelementes für verschiedene Bewegungsphasen des Antriebs nach den Fig. 13 und 14;

Fig. 16

ein Blockschaltbild einer Reglereinheit zur erfindungsgemäßen Steuerung des Antriebs nach der Fig. 13;

Fig. 17

Geschwindigkeitsverläufe für den Bauteil zu unterschiedlichen Regelungsfällen eines Startimpulses, in vereinfachter Darstellung;

Fig. 18

ein Zeitdiagramm der Signalverläufe der Sensoren und der Schaltelemente für verschiedene Bewegungsphasen des Antriebs nach den Fig. 1 und 2.

Show it:

Fig. 1

a block diagram with a first embodiment of a drive according to the invention in its right starting position, in a schematic representation;

Fig. 1a

a section of the drive according to the invention Fig. 1 with a control bar, in an enlarged and simplified representation;

Fig. 2

the drive off Fig. 1 in its left end position;

Fig. 3

a block diagram of the drive in its right starting position with another embodiment for its fluidic control, in a simplified representation;

Fig. 4

the drive after Fig. 3 in its left end position;

Fig. 5

a block diagram with another embodiment of the drive according to the invention in its right starting position;

Fig. 6

the drive after Fig. 5 in its left end position;

Fig. 7

a handling system with two drives coupled together for right-angled movements, in a schematic representation;

Fig. 8

a timing diagram of the waveforms of the sensors and the switching elements for different phases of movement of the drive after the Fig. 1 . 2 . 5 to 7 ;

Fig. 9

a diagram for explaining the advantageous effect of the early venting of the pressure in the previous movement phase at the end pressure chamber;

Fig. 10

a timing diagram of the waveforms of the sensors and the switching element for different phases of movement of the drive after the Fig. 3 and 4 ;

Fig. 11

the inventive method for controlling the fluidically actuated drive in the representation as a flowchart;

Fig. 11a

a block diagram of the in Fig. 11 in dashed lines registered, first control loop;

Fig. 11b

a block diagram of the in Fig. 11 in dashed lines registered, second control loop;

Fig. 12

the method according to the invention for controlling the fluidically actuated drive in a modified version, shown as a flowchart;

Fig. 12a

the timing diagram after Fig. 8 with the signal curve of the sensor arranged in the target end position, which detects a rebound movement of the component at the end position;

Fig. 12b

the timing diagram after Fig. 8 with the signal curve of the sensor arranged in the target end position, which detects a pendulum movement of the component before the end position;

Fig. 13

a block diagram of the drive in its right starting position with another embodiment for its control according to the invention, in a simplified representation;

Fig. 14

the drive off Fig. 13 in its left end position;

Fig. 15

a timing diagram of the waveforms of the sensors and the switching element for different phases of movement of the drive after the Fig. 13 and 14 ;

Fig. 16

a block diagram of a controller unit for controlling the drive according to the invention after the Fig. 13 ;

Fig. 17

Velocity curves for the component for different control cases of a start pulse, in a simplified representation;

Fig. 18

a timing diagram of the waveforms of the sensors and the switching elements for different phases of movement of the drive after the Fig. 1 and 2 ,

By way of introduction, it should be noted that in the differently described embodiments, the same parts are provided with the same reference numerals or the same component names, the disclosures contained in the entire description can be mutatis mutandis to the same parts with the same reference numerals or component names. Also, the location information selected in the description, such as above, below, laterally, etc. related to the immediately described and illustrated figure and are to be transferred to a new position in a change in position. Furthermore, individual features or combinations of features from the different exemplary embodiments shown and described can also represent independent, inventive or inventive solutions.

In the Fig. 1 and 2 a first embodiment of a drive 1 is shown in a schematic representation. The drive 1 is formed by a lifting cylinder 2, which consists of a cylinder tube whose ends are closed with end walls 3, 4. In this lifting cylinder 2, a control piston 5 is slidably guided by a pressure medium, which in turn is connected to a piston rod 6. The lifting cylinder 2 forms a guide device for the actuating piston 5. The fluidic pressure medium is compressed air or hydraulic oil. The piston rod 6 is fixedly mounted via a corresponding fixed bearing 7, so that the lifting cylinder 2 forms the moving component and the actuating piston 5 with the piston rod 6, the fixed component of the drive 1. The piston rod 6 extends through the right end wall 3 of the lifting cylinder 2 in the axial direction.

Between the left end wall 4 and the adjusting piston 5 is a first pressure chamber 8 and between the right end wall 3 and the adjusting piston 5, a second pressure chamber 9 is formed. As the illustrations show, the lifting cylinder 2 is a so-called double-acting fluid cylinder. The pressure chambers 8, 9 are alternately acted upon by this embodiment via two separate switching elements 10, 11, in particular two 3/2-way valves. The switching elements 10, 11 each have an electromagnetic control magnet 12 which is connected via corresponding control lines 14, 15 with an electronic control device 13, in turn, the switching elements 10, 11 between a rest position in the de-energized state of the control magnets 12 and actuation position in energized state Control solenoid 12 switches. The electronic control device 13 is preferably connected via an address-based network, in particular a bus system, with a higher-level control or formed by the higher-level control. The control of the control magnets 12 takes place here via electrical control signals of the control device 13 through which the switching elements 10, 11 are actuated, as shown in the Fig. 8 from the signal _curve for the switching position S _SCH1 , S _{SCH2 of} the switching elements 10, 11 can be seen.

The left pressure chamber 8 is connected via a first pressure line 16 to the first switching element 10 and the right pressure chamber 9 via a second pressure line 17 to the second switching element 11. The switching elements 10, 11 are in turn connected via a corresponding pressure supply connection to a pressure supply unit 18, for example a pneumatic or hydraulic pressure source, through which the pressure chambers 8, 9 alternately with system pressure, for example 6 bar acted upon.

As in the Fig. 1 and 2 further registered, the control device 13 is connected via signal lines 19, 20 with sensors 21, 22, so that the output from the sensors 21, 22, electrical control signals of the control device 13 can be fed. The sensors 21, 22 are formed for example by inductively acting sensors.

The sensors 21, 22 are arranged in the end positions to be approached by the lifting cylinder 2 above the movement path defined by the drive 1 or the lifting cylinder 2. The end positions are defined by, the hard stops forming end walls 3, 4. Of course, there is also the possibility that the first sensor 21 above the movement path of the drive 1 and the second sensor 22 are arranged below the movement path of the drive. The arrangement of the sensors 21, 22 shown is merely of a fundamental nature. In the arrangement of the sensors 21, 22, depending on the wiring, it is only necessary that they do not influence one another. At the left end of the lifting cylinder 2, which forms the movable component of the drive, a first control bar 25 is fixed, which in the in Fig. 2 shown position of the lifting cylinder 2 in the effective range of the first sensor 21 is located. The second sensor 22 is associated with a second control bar 26 at the right end of the lifting cylinder 2, which in the in Fig. 1 shown position of the lifting cylinder 2 in the effective range of the second sensor 22 is located. The control strips 25, 26 are thus fixed to the movable component of the drive 1 at its opposite ends, for example via a screw arrangement.

The control bar 25, 26, as in Fig. 1a is shown enlarged, is formed by a prismatic block and has on its the sensor 21, 22 facing upper side a switching lug 27 a, b and one of them via a recess groove 28 a, b separated end position portion 29 a, b. The width (B) of the recessed groove 28a, b is at least between 1 mm and 5 mm, in particular between 2 mm and 4 mm. The longitudinal distance (A) between control edges 32a, b, 33a, b is at most between 4 mm and 15 mm, in particular between 5 mm and 9 mm. In a subsequent to the end position portion 29 a, b section of the control bar 25, 26 is a bore 30 a, b arranged to receive a fastening screw, not shown. The switching lug 27a, b, the recess groove 28a, b and the end-position portion 29a, b are in the direction of movement of the lifting cylinder 2 - as indicated by arrow 31 in FIG Fig. 1 - arranged one behind the other. The length of the switching lug 27a, b is viewed by the in the direction of movement - as shown in arrow 31 - front side surface and by the towering, front groove side surface and the width of the transversely to the direction of movement - as indicated by arrow 31, opposite side surfaces of the control bar 25, 26th limited. The end-layer section 29a, b extends as a surface between the upwardly projecting rear groove side surface and the rear side surface of the control strip 25, 26 as well as between the lateral side surfaces of the control strip 25, 26 opposite the direction of movement, as shown in arrow 31 In the design of the control bars 25, 26, it is important that two control edges 32a, b, 33a, b provided in the direction of movement of the lifting cylinder 2 - according to arrow 31 - successively offset are at which a respective measurement signal S ₁ , S _{2 is} triggered when the control edge 32 a, b, 33 a, b enters the effective range of the respective sensor 21, 22, as will be described in more detail. Moreover, the control bar 25, 26 has a third control edge 34a, b, which lies between the first and second control edge 32a, b, 33a, b. A start signal S _{Start is} triggered via the second control edge 33a, b when the control edge 33a, b leaves the effective range of the relevant sensor 21, 22, as will be described in more detail.

In the Fig. 3 and 4 is the drive 1 according to the above-described embodiment with another embodiment of the control shown in a schematic representation. As the illustrations show, the lifting cylinder 2 is a so-called double-acting fluid cylinder.

The pressure chambers 8, 9 are alternately acted upon by this embodiment via only one switching element 36, in particular a 5/2-way valve. The switching element 36 has, for example, an electromagnetic control magnet 37 which is connected via a corresponding control line 14 with an electronic control device 13, which in turn switches the switching element 36 between a rest position in the de-energized state of the control magnet 37 and actuation position in energized state of the control magnet 37.

The control of the control magnet 37 takes place here via electrical control signals of the control device 13, by which the switching element 36 is actuated, as shown in the Fig. 10 from the waveform for the switching position S _{SCH of} the switching element 36 can be seen.

As in the Fig. 3 and 4 further registered, the left pressure chamber 8 via a first pressure line 16 and the right pressure chamber 9 via a second pressure line 17 to the switching element 36 are connected. The switching element 36 is connected to the pressure supply unit 18, through which the pressure chambers 8, 9 alternately with system pressure, for example 6 bar acted upon.

In the Fig. 5 and 6 a further embodiment variant of a fluidically actuated drive 1 'is shown, which comprises relatively adjustable components, of which the movable component via an actuator 40' along a guide device 41 'between a right end position, as in Fig. 5 shown, and a left end position, as in Fig. 6 shown, is adjustable. The movable component is formed by a guide carriage 42 'and the guide device 41' by a fixed to the fixed component linear guide, wherein the guide carriage 42 'is mounted on the linear guide. The fixed component is formed by a frame 43 'on which in the direction of movement - according to arrow 31- of the adjustable component opposite each other fixed stops 44' are arranged, by which the end positions are fixed. The fixed stops 44 'are formed for example by a screw-threaded arrangement and limit the maximum displacement of the movable member between the end positions.

As in the Fig. 5 and 6 Furthermore, it can be seen on the frame 43 'in the end positions opposite one another damper 45' are arranged. These mechanical shock absorbers 45 'fulfill primarily the task of reducing the impact load on the frame 43' in the commissioning of the drive 1 'or to prevent damage to the drive 1' during operation due to unforeseen faults.

The actuator 40 'is formed by a fluid cylinder, as this in the Fig. 1 to 4 has been described, and attached via a fastening device 46 with the cylinder housing on the frame 43 '. The piston rod 6 'of the actuator 40' is connected via a further fastening device 47 'with the guide carriage 42', so that the actuating piston 5 ' and the guide carriage 42 'are coupled in terms of movement and the retraction or extension movement of the piston rod 6' is transmitted to the guide carriage 42 '. The pressure chambers 8 ', 9' of the actuator 40 'are connected via the pressure lines 16, 17 with the switching elements 10, 11. The switching elements 10, 11 are connected to the pressure supply unit 18. The control magnets 12 of the switching elements 10, 11 are connected via the control lines 14, 15 with the electronic control device 13, which in turn drives the switching elements 10, 11. The sensors 21, 22 shown in the figures are fastened to the frame 43 'of the drive 1' and are connected to the electronic control device 13 via signal lines 19, 20.

The guide carriage 42 'is on its side facing the sensors 21, 22 in the direction of movement - according to arrow 31 - opposite ends with the control bars 25, 26 equipped, as in Fig. 1a are described in detail.

Fig. 7 shows a handling system 48, which is composed of a plurality of fluidly actuated drives 1 ', 1 ", the type of which, for example, in the Fig. 5 and 6 illustrated embodiment corresponds. The first drive 1 'is formed by a horizontal axis and the second drive 1 "by a vertical axis, the second drive 1" is fastened with its frame 43 "on the guide carriage 42' of the first drive 1 '"is formed by a guide carriage 42", which is mounted on the guide device 41 "vertically movable on the linear guide via the actuator 40. The fixed component is formed by the frame 43", on which in the direction of movement - according to arrow 31 - the movable In addition, shock absorbers 45 "are disposed opposite one another on the frame 43" in the end positions, on the guide carriage 42 "of the second drive 1" are the control strips 25, 26 and, for example, a attached pneumatically or hydraulically operated gripping system, the control bars 25, 26 with the stationary Sensors interact in the end positions. The pressure chambers of the actuator 40 "are also connected via pressure lines to one or two switching elements, as is not shown for reasons of clarity.

The control method of each drive 1 ', 1 "will be described in the following: As not shown in detail, in a preferred embodiment both drives 1', However, it would also be conceivable for each drive 1 ', 1 "to be connected to its own control device 13, each of which comprises a control unit and a memory. The control device (s) are preferably connected via an address-based network, in particular a bus system, for data or signal exchange with the higher-level control or formed by them. If two control devices 13 are used, they are connected to one another via a further, address-based network, in particular a bus system. Between the control devices 13 and / or the (n) control device (s) 13 and the higher-level control, the Ethernet can be used. Since the described drives 1 ', 1 "are usually integrated in a high number in a machine system, it is also advantageous if the sensors 21, 22 and the control magnet 12 of the switching elements 10, 11 for data or signal exchange with the control device 13 and / or the higher-level control to an address-based network, in particular a bus system, such as a fieldbus, are connected to which the control device (s) 13 and possibly the higher-level control can be connected.

Although the drive 1 ', 1 "in the Fig. 5 to 7 controlled by two 3/2-way valves, this could also be done only with a 5/2-way valve.

Fig. 8 shows the principle timing diagram for the drive 1; 1'; 1 "according to the embodiments shown in the Fig., 1 . 2 ; 5 . 6 ; 7 , The signal curve S _R for the feedback, the signal sequences S _E1 and S _{E2 of} the two sensors 21, 22 and the switch positions S _SCH1 and S _{SCH2 of} the switching elements 10, 11 are shown over the time of three movement _{phases of} the movable between the end positions component. According to the embodiment of the drive 1 according to Fig. 1 and 2 corresponds to the first and third movement phase of an extension movement according to arrow 31 - of the lifting cylinder 2 and the second phase of movement of a retraction - according to arrow 31 '- of the lifting cylinder. 2

At the start time T _start a start signal is transmitted via a higher-level control (not shown) of the electronic control device 13, as indicated in the figures by the arrow 50, whereby the first switching element 10 is activated by the control device 13 by energizing the control magnet 12 and the movable Component - the lifting cylinder 2 after Fig. 1 and the guide carriage 42 ', 42 "after Fig. 5 ; 7 - from its starting position in the direction of the arrow 31 is adjusted from right to left or up to down. By activating the switching element 10 in the in the Fig. 1 ; 5 shown, operated switching position brought and thus opens the pressure line 16, so that the pressure chamber 8; 9 'of the drive 1, 1' is connected to the pressure supply unit 18 and pressurized with system pressure. The second switching element 11 remains unactuated and is the pressure chamber 9; 8 'connected via the pressure line 17 with a vent line 51, so that in the pressure chamber 9; 8 'located pressure medium or working fluid can escape unhindered into the atmosphere. Therefore, in the right end position of the movable member, the pressure chamber 9; 8 'separated from the pressure supply unit 18.

Appropriately, with the activation of the first switching element 10 from the control device 13 to the higher-level controller, a confirmation signal is transmitted, as indicated by the arrow 52. This procedure confirms proper operation. By the pressurization of the pressure chamber 8; 9 ', the component moves from its initial position, which corresponds to the right end position, in the direction of the left end position.

By activating the first switching element 10, the first movement phase is initiated, as will be described in more detail below.

With the beginning of the movement of the component from its initial position or right end position to the start time T _start the control bar 26 is moved past the stationary sensor 22 and in this the in Fig. 8 signal sequence triggered. If, at the start time T _start, the end position section 29b of the control bar 26 faces the effective range of the sensor 22, the sensor 22 sends to the control device 13 an acknowledgment signal S _B. The confirmation signal S _B is still detected at the time of the standstill of the component. With the confirmation signal S _B the control device 13 is signaled that the component at the start time T _{start is} safe in its initial position and the first movement phase can be initiated. By this measure, a high reliability of the drive 1; 1'; If the confirmation signal S _B has not yet been output to the control device 13 at the start time T _start , an error message in the form of an optical and / or acoustic signal is output at an output device 53 of the control device 13 and / or at the higher-level control ,

After the start of movement of the component, the end position section 29 b leaves the effective range of the sensor 22 arranged in the start end position and a start signal S _{Start is} triggered at the control edge 33 b at the time T ₀ and transmitted to the control device 13. As will be explained later, the falling signal edge of the sensor 22 is evaluated. The further rising and falling signal edge, which are triggered at the edges 34b and 32b of the switching flag 27b are not evaluated on the movement of the component from its right end position to the left end position.

The arranged in the target end position sensor 21 is switched by the moving past these control bar 25. If the switching lug 27a with its control edge 32a enters the effective range of the stationary sensor 21, it triggers a first measuring signal S ₁ at the time T ₁ , which signal is passed on to the control device 13 via the signal line 19. At a later time T ₂ , which is in the movement phase, the end position section 29 a comes with its control edge 33 a into the effective range of the sensor 21 and triggers a second measurement signal S ₂ in the sensor 21, which is likewise transmitted to the control device 13 via the signal line 19. With the time T ₂ , the end of movement is reached. Like in the Fig. 8 As can be seen, the rising signal edges of the signal curves S _E1 , S _E2 are evaluated as measurement signals S ₁ , S ₂ . This is advantageous because now, regardless of the vertical distance between the control edge 32a, b, 33a, b and sensor 21, 22 always the same time t _{1Ist is} measured and an uncomplicated installation of the sensors 21, 22 on the drive 1; 1'; Although the measuring signal triggered by the control edge 34a of the switching lug 27a on the sensor 21 is detected as a falling signal edge, it is not evaluated.The control device 13 determines from the time difference between the measuring signals S ₁ , S ₂ a time interval t ₁ corresponds to the determined actual value t _1Ist in the first movement _phase .

As in the synopsis with Fig. 1 As can be seen, the control device 13 in addition to the output device 53 also has an electronic memory 54, an electronic control unit 55 and a computer module 56, in particular microprocessor, as shown schematically in the figures. The computer module 56 is integrated in the controller unit 55. In the memory 54 'This target value is matched, 1 "for the time period t _1To is to the different embodiments of the drives. 1; 1' for the time period t _1, a target value t _1To stored in retrievable form, of a type of drive 1, 1 determined mathematically or empirically from the determined time interval t _1Ist and the specified time interval t _1Soll is from the controller unit 55 the control device 13, a desired-actual comparison performed, a control deviation calculated from the difference between the setpoint and actual value and formed a control variable, as shown in the Fig. 11b is shown. The time span t _1Ist is thus determined during the movement _{phase of} the component and further processed in the manner indicated above by the control device 13.

According to the method of the invention, based on the control deviation from the first movement _phase of the component, a common first switching time T _{UZ1 of} the switching elements 10, 11 and a second, in the movement _phase subsequent, common switching time T _{UZ2 of} the switching elements 10, 11 calculated and stored in the memory 54 , If the third movement phase of the component is started, therefore the movement of the component in the same direction of movement as that of the first movement phase of the component, the previously calculated switching _times T _UZ1 , T _{UZ2 of} the switching elements 10, 11 are read from the memory 54 and at least one of the switching times T _UZ1 , T _{UZ2 are set} in the third movement _phase so that the control deviation is corrected, as in Fig. 11 will be described in more detail.

In the commissioning of the drive 1; 1'; 1 ", the switching _times T _UZ1 , T _{UZ2 of} the switching elements 10, 11 are predetermined by the control _{device 13.} For example, the switching _times T _UZ1 , T _{UZ2 of} the switching elements 10, 11 or 13 are respectively / for each direction of movement according to arrow 31, 31 ' a period of time t _GD in the last movement phase of the component before the stoppage of the drive 1, 1 ', 1 "is detected, stored and stored after the restart of the drive 1, 1'; 1 "in the first and second movement phase, before the initial startup of the drive 1, 1 ', 1", the switching _times T _UZ1 , T _{UZ2 of} the switching elements 10, 11 or the time period t _{GD are} likewise predetermined by the control _device 13.

As can be seen from the signal _curves for the switching positions S _SCH1 , S _{SCH2 of} the switching elements 10, 11, the first switching element 10 for the movement of the component from its starting position or right end position to the left end position is initially at the starting time T _start via a control device 13 to the control _solenoid 12 dispensed, redesign the first control signal into the operating position and held until the first switching time T _UZ1 in the operating position for the period t _SCH1 . Within this time period t _SCH1 becomes the Pressure chamber 8; 9 'vented with system pressure and thus pressurization of the component in the direction of movement - according to arrow 31- causes while the other switching element 11 for the period t _{SCH1 remains} in the rest position and the pressure chamber 9; 8 'depressurized or vented.

In the first switching time T _UZ1 , a second control signal is output by the control _device 13 to the control _magnets 12 again, with which the switching element 10 in the rest position and the switching element 11 in the operating position for a period of t _{GD are} redesigned. As a result, the originally pressurized pressure chamber 8; 9 'vented, the originally pressureless pressure chamber 9; 8 'vented with system pressure for the time t _GD and thus a small pressure pad just before the end of the movement phase of the component builds up, against which the moving component runs, so that a hard stop in the end position of the component is excluded.

The time period t _GD results from the time difference between T _UZ1 and T _UZ2 or the control signals output by the control _device 13 for reversing the switching elements 10, 11 and is determined by the control device 13, as in Fig. 11 is described. The time period t _GD for the duration of the counter-control of the pressure chambers 8, 9; 8 ', 9' is derived from the period t ₁ . By the reversal of the switching elements 10, 11 and change the pressure conditions in the pressure chambers 8, 9; 8 ', 9', a braking phase is inserted towards the end of the movement phase, in which by the in the pressure chamber 9; 8 'constructed pressure pad is a deceleration in the direction of movement - according to arrow 31- to the switching time T _{UZ1 moving} at the maximum possible speed component occurs. Accordingly, in the first switching time T _UZ1 the braking _{phase is} initiated and in the second switching time T _UZ2 the braking _{phase is} terminated. The braking phase is thus determined by the switching _times T _UZ1 , T _UZ2 and / or the duration of the countersteering or the time interval t _GD .

At the end of the braking _phase in the second switching time T _UZ2 , a third control signal is output again from the control _device 13 to the control _magnets 12 of the switching elements 10, 11, and the pressure chambers 8, 9; 8 ', 9' driven in opposite directions, wherein the component again shortly before reaching its end position in the direction of movement again with system pressure or the pressure chamber 8; 9 'in turn subjected to system pressure and the pressure chamber 9; 8 'is vented. As a result, the component experiences at the end of the braking phase, where this already one has low movement speed, again a feed in the direction of movement - according to arrow 31- in the direction of its left end position. This ensures that the component reliably reaches its end position. For this purpose, a third control signal corresponding Nachschaltsignal S _{NS is} generated in the second switching time T _UZ2 , through which the control device 13, the feed of the component in the original direction of movement - according to arrow 31 - causing switching element 10 at least until the end of the movement phase and with Reaching the end position is controlled. In a preferred embodiment, the Nachschaltsignal S _{NS is applied to} the control _magnet 12 of the switching element 10 for a period of time t _SCH2 until the start of movement of the component in the second movement _phase , in which the component from its left end position in its right end position in the opposite direction of movement - ' - is moved. Thus, over the entire period t _SCH2 in the pressure chamber 8; 9 ', the system pressure and is held by the component positioned for a certain time in the approached end position. The time interval t _SCH2 results from the time difference between the second switching time T _UZ2 and a third switching time T _{UZ3 of} the switching elements 10, 11. In the third switching time T _UZ3 is again issued by the control _device 13 to the control _magnets 12 of the switching elements 10, 11, a fourth control signal and the pressure chambers 8, 9; 8 ', 9' driven in opposite directions. The fourth control signal corresponds to the start signal for the second movement phase at time T _start . The switching element 11 is always driven in opposite _directions to the switching element 10 and remains for the period t _SCH2 in its rest position.

As can be seen from the described, the switching elements 10, 11 and the pressure chambers 8, 9; 8 ', 9' within a movement _phase abruptly and in opposite _directions , are _controlled exactly to the calculated switching _times T _UZ1 , T _UZ2 and _{predetermined} by the control device 13 or the higher-level control switching T _UZ3 , as is achieved by known from the prior art quick- _{acting valves} ,

Also advantageous is a measure in which prior to the start of movement of the component in the opposite direction of movement - according to arrow 31 '- therefore before the start time T _start the second movement phase of the control device 13 that switching element 10, a pilot signal S _VS supplied and its switching state is changed , which causes the pressurization in the direction of movement - as indicated by arrow 31-, as in dashed lines in Fig. 8 entered. The pilot control signal Svs is triggered at the pre-control time T _VS. The Time difference between the pre-control time T _VS and the start time T _start for the second movement _phase corresponds to the time t ₂ , wherein the start time T _start the third switching time T _{UZ3 of} the switching elements 10, 11 corresponds. The period t ₂ is preferably determined empirically and stored in the memory 54 of the control device 13 retrievable. As described above, the third switching time T _{UZ3 of} the switching elements 10, 11 is specified by the control device 13 or the higher-level control. The pre-control time T _VS is calculated in each movement _{phase of} the component from the time difference between the switching time T _UZ3 and the time t ₂ and switched before the movement of the component in the previous movement _phase opposite direction of movement, the pressurization in the direction of movement of the component causing switching element 10, 11 ,

If the pilot control signal Svs is triggered by the control device 13, as shown in FIG Fig. 8 the pressure chamber 8 pressurized with system pressure in the first movement phase; 9 'vented before the start of movement of the component in the second movement phase or the pressure in this pressure chamber 8; 9 'reduced, so that the movement of the component to the start of movement in the second movement phase counteracts only a minimized or no counterforce. This is advantageous since, with the drive force set by the system pressure, a high acceleration is achieved at the start of movement of the second movement phase and, further, the movement time of the component between the end positions is substantially reduced, as shown in FIG Fig. 9 is shown as a diagram for example for the first movement phase. As can be seen from this, the movement time of the component in the subsequent movement phase - according to the representation according to Fig. 8 in the second movement phase - by the "early" venting in the previous movement phase - according to the representation according to Fig. 8 in the first movement phase - pressurized pressure chamber 8, 9; 8 ', 9' are reduced with increasing duration of the venting time.

The switching element 11, however, is switched by the control device 13 at the start time T _start , whereby the pressure supply unit 18 via the switching element 11 and the pressure line 17 to the pressure chamber 9; 8 'connected and this is acted upon by the system pressure, so that the component is moved from its left end position to the right end position. According to this embodiment, the time span t _SCH2 for the switching element 10 effecting the movement of the component results from the time difference between the second switchover time T _UZ2 and the pilot control _signal S _VS , but this is not entered in the _FIGURE . The time period t _SCH2 for the other switching element 11 remains unchanged.

As in Fig. 8 further entered, are still evaluated by the control device 13, the time periods t ₃ , t ₄ and t ₅ . The time interval t ₃ is determined by the control _device 13 from the time difference between the third control signals for the second switching time T _UZ2 and the first measuring signal S ₁ at the time T ₁ as the actual value t _3Ist . In the memory 54 of the control device 13, a setpoint value t _{3soll is also} stored for the time period t ₃ , which is tuned to a type of drive 1, 1 ', 1 "and mathematically calculated or determined empirically Fig. 11a is described in more detail, is carried out by the electronic control unit 55 between the set time t _3Soll and the determined time t _3Ist a target-actual comparison, a control deviation calculated from the difference between the setpoint and actual value and formed a control variable. On the basis of the control deviation, the first and / or second switching time T _UZ1 , T _{UZ2 of} the switching elements 10, 11 are set for the respective next movement _{phase of} the component in the same direction of movement - and the time period t _{GD is} set in the same direction of movement.

The entered time period t ₄ is triggered at the time T ₂ and ends at a later time, in which it is ensured that all arithmetic operations of the control unit 55 are completed and the control deviation or manipulated variables for the next movement phase are available in the same direction of movement. This time period t ₄ can for example be fixed and is stored in the memory 54. After completion of the calculations of the control deviations, the control device 13 generates a release signal with which the second movement phase of the component can be started by the control device 13 or superordinate control. This design is used when, due to the movement of the drive 1; 1'; 1 "is known that between the first and second movement phase of the drive 1, 1 ', 1" the component remains in the respective end position for a certain time, within which the calculations of the deviations and all other mathematical functions can be completed. This application corresponds to the usual use of the drive 1 according to the invention; 1'; 1 "as the axis of a multi-axis handling system, after which the computer power of the control device 13 can be designed lower.

But it is equally possible that a powerful microprocessor is used, which carries out the calculations of the control deviations and all other mathematical functions from the first movement phase within the second movement phase, so that the corresponding manipulated variables and other calculation results, such as the pre-control time T _VS , be available before the start of the third movement phase. This design is used when an alternating movement of the component is required and the residence time of the same should be as low as possible in its end positions.

As in Fig. 8 registered, at the start of movement of the component by the control device 13, the time t _{5 is} determined, which results from the time difference between the control signal at the start time T _start of the movement of the component-initiating switching element 10 and the start signal S _start at time T ₀ . This period of time t ₅ resulting from the inertia of the system, for example from the switching time of the switching element 10, pressure propagation in the pressure lines 16, 17, friction between the relatively movable components, mass of the moving member and the like To this inertia of the drive. 1; 1'; 1 "to be compensated, the first control signal or switching signal for the movement of the component causing switching element 10 by the time t ₅ earlier than the actual start of movement of the component triggered and thereby the pressurization of the component prematurely initiated, so that the inertia of the drive 1; 1 ', 1 "does not cause a negative effect on the movement time of the component.

After according to Fig. 8 the first phase of movement corresponds to the movement of the component from its initial position to the left end position, the time t _{5 is} read out of the memory 54. For this purpose, before stopping the drive 1; 1'; 1 ", the determined time intervals t ₅ from the last movement phase of the component of each movement direction - according to arrow 31, 31 '- stored in the memory 54. In the commissioning of the drive 1; 1', 1" is after the restart of the drive 1; 1'; 1 "for the first movement phase of the component, the determined time intervals t ₅ from the last movement phase of the component of the same direction of movement - according to arrow 31 - and for the second phase of movement of the component, the determined time intervals t ₅ from the last phase of movement of the component in the same direction of movement - as indicated by arrow 31 '- used.

In operation, the time interval t _{5 is} calculated continuously in all movement phases, stored in the memory 54 and used in the next movement phase in the same direction of movement. The control device 13 determines or calculates the time period t _5, for example, in the first movement phase and switches these or the higher-level control in the third movement phase, the switching element 10 to the calculated from the first movement phase, new start time T _start .

Are like in Fig. 7 shown, for example, two actuators 1 ', 1 "motionally coupled to one another, it is advantageous that the at least one control means 13 and / or higher-level control before the completion of the phase of movement of the first actuator 1' given a feedback signal S _Re and the starting time T _Start of the second drive 1 "is submitted at least by the time period t ₅ . At the start time T _start the movement of the component causing switching element is switched, the corresponding pressure chamber of the actuator 40 "applied system pressure and the guide carriage 43", for example, adjusted from top to bottom between its end positions. The inertia is compensated by the leading feedback or the leading feedback signal S _Re , so that the second drive 1 "actually starts its movement when the first drive 1 'has reached its end position ,

However, the acknowledgment signal S _Rück does not necessarily have to be output in advance, that is to say before the end of the movement phase of the first drive 1 'to the control device 13 or superordinate control (not shown). Are also conceivable applications in which the feedback signal S is delivered _back simultaneously with the attainment or after reaching the end position of the first actuator 1 '. This may be the case when the second drive 1 "is equipped with a laser beam head, which must be moved from the end position of the first drive 1 'by means of the second drive 1" defined to a weld. In order for the laser beam head to be absolutely vibration-free until the welding point is reached, the movement of the second drive 1 "with the laser beam head is started at the earliest when the end position of the first drive 1 'is reached.

The time T _R (shown in Figs. Unrecorded) in which the feedback signal S _back is triggered, is calculated by the control device 13 or the higher level control and results from the difference between the time T _{2 of} the sensor 21 from the first drive 1; 1 'and the time t ₅ to the start of movement of the second drive 1 ". Since the time T ₂ is not recognized until reaching the to-propelled end position, this need for the calculation of the time T _R of the preceding movement phase of the actuator 1' are used, after which from the control device 13, the time T _R for the subsequent movement phase of the second drive 1 "can be determined.

It is understood that in the reverse direction of movement - according to arrow 31 '- a correspondingly reverse control of the switching elements 10, 11 takes place, as in Fig. 8 registered for the second movement phase, wherein the corresponding measurement signals S ₁ , S ₂ are triggered by the sensor 22, the confirmation signal S _B and start signal S _start from the sensor 21. The switching element 11 receives at time T _start the first control signal for the beginning of the movement of the component from its left end position to the right end position again from the control device 13 or the higher-level control. Also for this movement direction, the control device 13, the first and / or second switching time T _UZ1 , T _{UZ2 of} the switching elements 10, 11 is calculated at a control deviation in the second _phase of movement of the component and in the fourth _phase of movement of the component of the first and / or second Switching time T _UZ1, T _{UZ2 of} the switching elements 10, 11 set accordingly.

Fig. 10 shows the principle timing diagram for the drive 1 according to the embodiments shown after the Fig., 3rd . 4 , The signal curve S _R for the feedback, the signal sequences S _E1 and S _{E2 of} the two sensors 21, 22 and the switching position S _{SCH of} the switching element 36 are shown over the time of three movement phases of the movable between the end positions component. According to the embodiment of the drive 1 according to Fig. 3 and 4 corresponds to the first and third movement phase of an extension movement - according to arrow 31- of the lifting cylinder 2 and the second phase of movement of a retraction - according to arrow 31 '- of the lifting cylinder 2. It is at this point on the detailed description of the determination of the different signal waveforms S _R , S _E1 , S _E2 , times T ₁ , T _start , T ₀ , T ₁ , T ₂ , T _UZ1 , T _UZ2 , T _UZ3 , T _R and time periods t ₁ , t ₃ , t ₄ t ₅ , t _SCH1 , t _SCH2 renounced, since these after those Fig. 8 correspond.

At the start time T _Start , a start signal is initially transmitted via a higher-level control (not shown) to the electronic control device 13, as shown in the figures Arrow 50 indicated, and then discharged from the control device 13 to the control magnet 37, a first control signal, whereby the control magnet 37 is energized and the switching element 36 is switched to the operating position and the movable member - according to the embodiment of the lifting cylinder 2 - from its initial position in the direction of Arrow 31 is adjusted from right to left. Now is the switching element 36 in the in Fig. 3 shown actuating position, the pressure line 16 is opened, so that the pressure chamber 8 of the drive 1 is connected to the pressure supply unit 18 and pressurized with system pressure, while the pressure chamber 9 is connected via the pressure line 17 with a vent line 51 on the switching element 36, so that in the pressure chamber. 9 located pressure medium or working fluid can escape unhindered into the atmosphere. Therefore, in the right end position of the movable component, the pressure chamber 9 is disconnected from the pressure supply unit 18.

With the beginning of the movement of the component from its initial position or right end position to the start time T _start the control bar 26 is moved past the stationary sensor 22 and in this the in Fig. 10 signal sequence triggered. This waveform corresponds to that in Fig. 8 and is therefore waived a second description at this point.

The arranged in the end position sensor 21 is switched by the moving past these control bar 25. If the switching lug 27a with its control edge 32a enters the effective range of the stationary sensor 21, it triggers a first measuring signal S ₁ at the time T ₁ , which signal is passed on to the control device 13 via the signal line 19. At a later time T ₂ , which is in the movement phase, the end position section 29 a comes with its control edge 33 a into the effective range of the sensor 21 and triggers a second measurement signal S ₂ in the sensor 21, which is also transmitted to the control device 13. Please refer to the detailed description here Fig. 8 referred to, in which the signal waveform is explained on the sensor 21, and is therefore taken at this point by a repetition distance.

According to the method of the invention, a first switching time T _{UZ1 of} the switching element 36 and / or a second switching point T _{UZ2 of} the switching element 36 subsequent to the movement _{phase are} calculated and stored in the memory 54 on the basis of the control deviation in the first movement _phase of the component. If the third movement phase of the component is started, therefore, the movement of the component in the same direction of movement as the the first movement phase of the component, the previously calculated switching time (s) T _UZ1 , T _{UZ2 of} the switching elements 36 are read from the memory 54 and set at least one of the switching _times T _UZ1 , T _UZ2 in the third movement _phase so that the control deviation corrected.

As can be seen from the signal curve for the switching position S _{SCH of} the switching element 36, the switching element 36 is emitted to the starting position T _start via the control device 13 to the control magnet 37 for movement of the component from its starting position or right end position into the left end position. redesign the first control signal into the actuation position and _held in the actuation position for the time span t _SCH1 until the first changeover time T _UZ1 . Within this period of time t _SCH1 the pressure chamber 8 is vented with system pressure and thus a pressurization of the component in the direction of movement - as indicated by arrow 31- causes while the pressure chamber 9 is vented.

In the first switching time point T _UZ1 , a second control signal is output by the control _device 13 to the control _magnet 37, with which the switching element 36 is transformed into the rest position for a time period t _GD . As a result, the originally pressurized pressure chamber 8 is vented, the originally pressureless pressure chamber 9 for the time t _GD vented with system pressure and thus a small pressure pad just before the end of the phase of movement of the component, against which the moving component runs, so that a hard stop in the End position of the component is excluded.

The time interval t _GD results from the time difference between T _UZ1 and T _UZ2 or the control signals output by the control _device 13 for reversing the switching element 36 and is determined by the control device 13. By reversing the switching element 36 or its switching positions and changing the pressure conditions in the pressure chambers 8, 9, a braking phase is inserted towards the end of the movement phase, in which a deceleration of the in the direction of movement - as indicated by arrow 31- by the built-up in the pressure chamber 9 pressure pad. takes place at the switchover time T _UZ1 with the maximum possible speed of the moving component.

At the end of the braking _phase in the second Umschaltzeitpunlct T _UZ2 is again issued by the control _device 13 to the control _magnet 37 of the switching element 36, a third control signal and the pressure chambers 8, 9 driven in opposite directions, wherein the component shortly before reaching its end position in the direction of movement in turn with system pressure or the pressure chamber 8 is pressurized with system pressure and the pressure chamber 9 is vented. As a result, at the end of the braking phase, where it already has a low speed of movement, the component again experiences an advance in the direction of movement - as indicated by arrow 31- in the direction of its left end position. This ensures that the component reliably reaches its end position. For this purpose, a third control signal corresponding Nachschaltsignal S _{NS is} generated in the second switching time T _UZ2 , which is the control _magnet 37 is switched on for a period of time t _SCH2 to the start of movement of the component in the second movement _phase . The effect of the subsequent signal S _NS has already been described in detail above.

In the third switching time T _UZ3 , a fourth control signal is output again from the control _device 13 to the control _magnet 37 of the switching element 36, and the pressure chambers 8, 9 are actuated in opposite directions. The fourth control signal corresponds to the start signal for the second movement phase at time T _start .

It is understood that in the reverse direction of movement - according to arrow 31 '- a correspondingly reversed activation of the switching element 36 takes place, as in Fig. 10 registered for the second movement phase, wherein the corresponding measurement signals S ₁ , S ₂ are triggered by the sensor 22, the confirmation signal S _B and start signal S _start from the sensor 21. The switching element 36 is for this purpose of the in Fig. 3 entered operating position in the in Fig. 4 registered rest position switched by the starting time point T _start the second movement phase of the parent control or control device 13 of the control magnet 37 is driven to the first control signal and the control magnet 37 is moved to the de-energized state. As a result, the component is moved from its left end position counter to the original direction of movement - according to arrow 31- in the right end position. In this switching position of the switching element 36, the pressure line 17 is opened, so that the pressure chamber 9 of the drive 1 is connected to the pressure supply unit 18 and pressurized with system pressure, while the pressure chamber 8 is connected via the pressure line 16 with a vent line 51 on the switching element 36, so that the located in the pressure chamber 8 pressure medium or working fluid can escape unhindered into the atmosphere. Also for this direction of movement, is in the second phase of movement of the component of the _controller 13 of the first and / or second switching time T _UZ1 , T _{UZ2 of} the switching element 36 is calculated and set in the fourth _phase of movement of the component of the new, first and / or second switching time T _UZ1 , T _{UZ2 of} the switching element 36 accordingly.

The inventive method for controlling the fluidically actuated drive 1; 1'; 1 "is now based on the in the Fig. 11 to 12b described procedures described in more detail.

The start of movement of the component in the first movement phase is symbolized by block 70 and the end of movement of the component in the first movement phase by block 71. The movement of the component is monitored by means of a monitoring device 72 having the control device 13, as shown schematically in the preceding figures. This monitoring device 72 is formed, for example, by an electronic or programmed counter, which detects the number of state changes of a signal level between a high level and a low level of the sensor 21 and / or 22. A value for the minimum number of state changes of a signal level between a high level and a low level of the sensor 21 and / or 22 is stored in the memory 54 of the control device 13.

In method step 73, the controller 13 performs a comparison between the determined number of state changes of a signal level between a high level and a low level and a specified minimum number of state changes of a signal level between a high level and a low level, and an evaluation performed. If the determined number of state changes falls below the specified minimum number of state changes, an error message is displayed on the output device 53 of the control device 13 and / or on the higher-level control. This error message is shown as block 74. After this execution, the minimum number of state changes is set greater than one and an error message is issued, if the determined number of state change is, for example, one or zero. The cause of the error message may be, for example, a defective sensor 21, 22 or a hindrance to the movement of the component. The latter, for example, if a technical defect on the drive 1; 1'; 1 "occurs or a mounting part on the drive 1, 1 ', 1" clamped and thereby movement of the component is prevented.

If, however, the determined number of state changes is higher than the specified minimum number of state changes, method step 75 is initiated.

In this method step 75, a setpoint-actual comparison between the set time interval t _3setpoint and the determined time interval t _3Ist is first carried out by the control unit 55 of the control _{device 13} . If the determined time interval t _{3Ist deviates} from the set time interval t _3Soll , a control variable for setting the switching _times T _UZ1 , T _{UZ2 is} formed from these in a first control loop of the control unit 55.

In Fig. 11a the first control loop is shown in detail. As can be seen, in the first movement _phase for the next movement _phase in the same direction of movement of the component on a comparison _element 76, a control deviation (e) between the determined time interval t _3Ist and the set time t _{3Soll is} calculated and fed to a first controller 77 of the control unit 55. In the controller 77, the manipulated variables for setting both switching _times T _UZ1 , T _{UZ2 are} calculated from the control deviation (e) according to a defined control _law and then stored in the memory 54. If the movement of the component in the third movement phase is now started, the corresponding manipulated variables are read from the memory 54 and applied to the switching elements 10, 11 according to the explanations in FIGS Fig. 1 . 2 ; 5 . 6 ; 7 or the switching element 36 according to the embodiment in the Fig. 3 . 4 switched. The switching elements 10, 11; 36 form the actuators of the control loop, as these, however, in the Fig. 11a are not shown. It can therefore be seen from the above that, given a deviation of the time span t _3Ist from the time interval t _3Soll , the switching _times T _UZ1 , T _{UZ2 are readjusted} for the next movement _phase in the same direction. In this way it is now ensured that a control deviation (e), which is determined in a previous movement _phase in the first direction of movement - as indicated by arrow 31-, by changing the switching _times T _UZ1 , T _UZ2 and in the subsequent movement _phase in the same direction of movement - according to arrow 31- the or the switching element (s) 10, 11; 3 6 after the calculated switching _times T _UZ1 , T _{UZ2 be} controlled so that the detected time t _3Ist the set time t _3Soll corresponds. According to this regulation, the new switching _times T _UZ1 , T _{UZ2 are} calculated, wherein the time period t _GD remains unchanged in all subsequent _{phases of} movement in the same direction of movement - according to arrow 31-. As a result, this control _{intervention substantially} corresponds to a shift of the switching _times T _UZ1 , T _UZ2 at a constant distance with respect to the time T ₁ . On the other hand, if the actual value of the ascertained time interval t _{3Ist corresponds to} the specified setpoint of the time interval t _3Soll , a control intervention and thus a shift of the switching _times T _UZ1 , T _UZ2 on the time axis with respect to the time T _{1 can be} omitted and the method step 78 is initiated immediately.

In this method step 78, the setpoint-actual comparison of the set time interval t _1setpoint and the determined time interval t _1actual is again effected by the controller unit 55. If the determined time interval t _{1Ist deviates} from the set time interval t _1setpoint , in the first movement _phase for the next movement _phase in the same direction of movement of the component the control deviation (e) is initially formed on a comparison element 79 and fed to a second controller 80 of the control unit 55 in Fig. 11b shown as a second control loop of the control unit 55. In the controller 80, only one manipulated variable for setting the switching time T _UZ1 or the time interval t _{GD is} formed from the control deviation (e) according to a defined control law and then stored in the memory 54. If the movement of the component in the third movement phase is now started, then the corresponding manipulated variable is read from the memory 54 and applied to the switching elements 10, 11 according to the explanations in FIGS Fig. 1 . 2 ; 5 . 6 ; 7 or the switching element 36 according to the embodiment in the Fig. 3 . 4 switched. Accordingly, the second switching time T _{UZ2 is} maintained in this control loop and the time period t _GD or the duration of the counter control changed by the first switching time T _{UZ1 is shifted} on the time axis.

Corresponds to the time period t, however, determined _1If the specified period t _1To, a change in the time period t _DG or the duration of the counter controlling omitted and the component based on the force in the last movement phase setting for the first switching time T _UZ1 driven.

The first and second regulators 77, 80 of the control unit 55 are formed by an I-controller. A simplification of the control _method is also achieved by _setting the time periods t _1soll , t _3soll as a time window with a lower and upper limit and a control intervention takes place only if the determined time intervals t _1Ist , t _3Ist outside the time or tolerance _window lie. The lower and upper limits of the time window are defined in such a way that nevertheless an optimal deceleration behavior and smooth approach of the end position is possible.

Fig. 12 shows a modified method for controlling the drive 1; 1 ', 1 "in a flow chart The modification concerns the consideration or correction of the movement sequence of the component On the one hand it can happen that the component is moved too fast against the end position and due to the high kinetic impact energy is moved from the end position against the target movement and at the, to be approached end position associated sensor 21 results in a waveform, as in Fig. 12a is shown. On the other hand, the case may occur that the component is moved at too low a speed against the end position and it performs a pendulum motion before reaching the end position, so that the in Fig. 12b shown signal waveform for the located in the approaching end position sensor 21 results. The end position is formed by a mechanical limiting element, such as a fixed stop or shock absorber.

In order to be able to differentiate between these two cases, during the movement of the component via the monitoring device 72 entered in the previous FIGURE, the signal profile at the sensor 21 arranged in the end position to be approached is determined and the number of state changes of a signal level between a high Level and low level evaluated. If the determined number of state changes of a signal level at the sensor 21 exceeds a limit number of state changes of a signal level determined by the control device 13, the method step 82 is initiated.

In method step 82, the control unit 55 of the control _{device 13 carries} out a desired / actual comparison between a defined time interval t _1setpoint and the determined time interval t _1ist . If the determined time interval t _{1 1st falls below} the defined time interval t _1setpoint , the control _device 13 can determine by evaluating the signal _curve that the component has been moved into the end position at too high a speed.

This situation is based on the in Fig. 12a shown waveform. In this case, the control device 13 is supplied with three measurement signals S ₁ , S ₂ , S ₃ . The first measuring signal S ₁ is detected at a time T ₁ when, for example, the control strip 25 attached to the moving component enters the effective range of the sensor 21 arranged in the approaching end position in the direction of movement - as indicated by arrow 31 - front control edge 32 a, while the second Measuring signal is detected at a time T ₂ , in which the control bar 25 with the second control edge 33 a in the effective range of the sensor arranged in the end position to be approached 21 enters. If the speed of movement of the component is too high, it is initially moved counter to its desired movement due to its excessive impact energy at the end position and then driven by the repeated application of pressure for safe starting of the end position in its original direction of movement. As a result, the component is again moved in the direction of the end position and braked against the end position, so that the second control edge 33a again enters the effective range of the arranged in the end position sensor 21 and thereby triggers the third measurement signal S ₃ at a later time T ₃ , However, this third measurement signal S ₃ is not evaluated by the control device 13.

Since the time period t _{1Ist is} far too low for the described situation, the second control loop is run through as described above. It is essential that the corrected period of time t _GD calculated on the basis of the previous movement phase and only in the subsequent movement phase in the same direction of movement of the component, the corrected or reduced time period t _{GD is} set. The setting of the time period t _GD is again carried out by the correction of at least one of the switching _times T _UZ1 , T _{UZ2 of} the switching elements 10, 11; 36th

In contrast, if determined in step 82 that the time period calculated t _1If the predetermined period of time exceeds t _1To, this is evaluated as a pendulum movement in the first movement phase of the control device 13, the t by reducing the period of time _GD is eliminated. For this purpose, the time interval t _GD stored in the memory 54 is multiplied by a weighting factor which is defined, for example, as a constant between 0.6 and 0.8. However, it is equally possible to specify the _{weighting factor} as a function of the deviation between the set time interval t _1setpoint and the determined time interval t _1ist . This process is indicated by a block 83 in FIG Fig. 12 shown. The time period t _GD corrected by the weighting _factor is again used as a new time interval t _GD in the third movement phase.

This situation is based on the in Fig. 12b shown waveform. In this case, the control device 13 is supplied with three measurement signals S ₁ , S ₂ , S ₃ . The first measuring signal S ₁ is detected at a time T ₁ when, for example, the control strip 25 attached to the moving component enters the effective range of the sensor 21 arranged in the approaching end position with the control edge 32 a in the direction of movement. If the speed of movement of the component is too low, the component is still before reaching the end position moved counter to its desired movement, so that the control bar 25 again leaves the effective range of the sensor 21. By applying pressure to safely approach the end position, the component is again driven in its original direction of movement, so that the front control edge 32a at time T ₂ again enters the effective range of arranged in the end position sensor 21 to be approached. If the end position is reached, then at a later time T ₃ , when the control edge 33a enters the effective range of the sensor 21, the third measurement signal S _{3 is} triggered, in which the component has actually reached the end position. However, this third measurement signal S ₃ is not evaluated by the control device 13.

The in the Fig. 12a . 12b Registered time interval t ₄ is triggered at time T ₃ and ends at a later time, in which it is ensured that all arithmetic operations of the control unit 55 are completed and the control deviation or manipulated variables for the next movement phase are available in the same direction of movement. The end of movement is reached only at time T ₃ . Similarly, a displacement of the time point T _R occurs (in FIGS. Unrecorded) one in which the feedback signal S _back is triggered.

As described above, the end position can be determined either solely by the skillful control of the drive 1; 1'; 1 "or by the combination of the skillful control of the drive 1, 1 ', 1" and a shock absorber gently approached. If a shock absorber is used, then that part of the kinetic impact energy of the component is absorbed, which was not degraded by the countermeasures over the time period t _GD . Therefore, the proportion of the kinetic energy to be absorbed by the shock absorber is significantly influenced by the duration of the countersteering t _GD . As described above, the time period t _GD for the duration of the counter-control results from the period t ₁ . The shock absorber acts with its spring force counter to the direction of movement of the component, so that the determined period t _{1Ist will} slightly increase when the moving component runs onto the shock absorber. On the other hand, the time span t _GD for the duration of the countermeasure is slightly reduced by the control from the determined time span t _1Ist . If the shock absorber _fails due to a defect or if it has been mounted incorrectly, the time span t _{1Ist is} significantly reduced, so that the time span t _GD for the duration of the countersteering is increased by the control from the determined time interval t _1Ist . To a failure of the shock absorber via the control device 13 or to be able to detect the higher-order control, a time lower limit and upper limit are specified for the time period t _GD . If the calculated time interval t _{GD exceeds} the upper limit defined by the control device 13 and stored in the memory 54, an error message in the form of an optical and / or acoustic signal is output at the output device 53 or the higher-level control and / or the drive 1; 1'; 1 "shut down.

It should be noted at this point that the switching _times T _UZ1 , T _UZ2 or the time period t _GD for the third movement _{phase are} still calculated in the first and / or second movement phase or during the residence time of the component in the end position.

In the jointly described Fig. 13 to 18 shows another embodiment of the method according to the invention, which may optionally represent an independent, inventive solution.

Fig. 13 shows a drive 100, which is also formed according to this embodiment by a double-acting lift cylinder 101, which consists of a cylinder tube, the ends of which are completed with end walls 102, 103. In this lifting cylinder 101 is displaceable by a pressure medium, a control piston 104 out, which in turn is connected to a piston rod 105. The piston rod 105 is mounted in a stationary manner via a corresponding fixed bearing 106, so that the lifting cylinder 101 forms the movable component and the adjusting piston 104 with the piston rod 105 forms the stationary component of the drive 100. Between the left end wall 103 and the control piston 104, a first pressure chamber 107 and between the right end wall 102 and the control piston 105, a second pressure chamber 108 is formed.

The pressure chambers 107, 108 are acted upon by this embodiment via only one switching element 109, in particular a 5/3-way valve alternately with system pressure. The switching element 109 has, for example, two electromagnetic control magnets 110, which are connected via corresponding control lines 111, 112 with an electronic control device 116, which in turn controls the switching element 109. In the de-energized state of the control magnets 110, the 5/3-way valve is in the unentered middle position (B). In the middle position (B), both pressure chambers 107, 108 are connected to return ports of the 5/3-way valve. In energized state (first operating position A) of left control solenoid 110, the first pressure chamber 107 via a first pressure line 113 to the pressure supply unit 114 and in energized state (second operating position C) of the right control solenoid 110, the second pressure chamber 108 via a second pressure line 115 to the pressure supply unit 114 is connectable. The switching element 109 is connected to the pressure supply unit 114. The control of the control magnet 110 takes place here via electrical control signals of the control device 116, as shown in FIG Fig. 15 from the signal curve for the switching position S _{SCH of} the switching element 109 can be seen.

As further noted in the figures, the control device 116 is connected via signal lines 117, 118 to sensors 119, 120, so that the electrical control signals output by the sensors 119, 120 can be fed to the control device 116. The control device 116 may also be formed by the higher-level control. In this case, the sensors 119, 120 are arranged in a stationary manner above the travel path defined by the drive 100 in the end positions to be approached by the movable component. These sensors 119, 120 cooperate with switching lugs 27a, b of the control bars 25, 26 described above, which are fastened to the opposite ends of the movable component, therefore the lifting cylinder 101. The arrangement of the control strips 25, 26 shown is only of a fundamental nature. Switching lugs 27a, b may equally well be used, which are formed by a prismatic block, or reed switches are used, ie sensors with which the end positions of the component without switching lugs 27a, b is monitored. It is essential that, via the sensors 119, 120 arranged in the end positions, an actual movement time t _BIst of the component moved between the end positions is detected exactly.

Fig. 15 shows the principle timing diagram for the drive 100. The signal sequences S _E1 and S _{E2 of} the two sensors 119, 120 and the switching position S _{SCH of} the switching element 109 over the time of three movement phases of the movable between the end positions component. According to the embodiment shown, the first and third movement phase corresponds to an extension movement - according to arrow 31 - of the lifting cylinder 101 and the second movement phase of a retraction movement - according to arrow 31 '- of the lifting cylinder 101st

At the start time T _start , a start signal is initially transmitted via a higher-level control (not shown) to the electronic control device 116, as in the FIGS Fig. 13 and 14 indicated by the arrow 50, and then from the controller 116 to the left Control magnet 110 outputs a first control signal, whereby the control magnet 110 is energized and the switching element 109 is switched to the actuating position (A) and the movable member - according to shown embodiment of the lifting cylinder 101 - is adjusted from its initial position in the direction of arrow 31 from right to left. Now is the switching element 109 in the in Fig. 13 shown actuating position (A), the pressure line 113 is opened, so that the pressure chamber 107 of the drive 100 is connected to the pressure supply unit 114 and pressurized with system pressure, while the pressure chamber 108 is connected via the pressure line 115 with a vent line 125 on the switching element 109, so that in the pressure chamber 108 located pressure medium can escape unhindered into the atmosphere.

By activating the switching element 109, the first movement phase is initiated, as will be described in more detail below.

With the beginning of the movement of the component from its initial position or right end position to the start time T _start the control bar 26 is moved past the stationary sensor 120 and in this the in Fig. 15 signal sequence triggered. This waveform corresponds to that in Fig. 8 and is therefore waived a second description at this point.

According to the inventive method, a setpoint value for the movement time t _{BSoll of} the component between the end positions of each movement _{phase is} statically predetermined or dynamically determined before the actual movement _start of the component at the start time T _start of the control device 116 or the higher-level control (not shown). The statically predetermined desired value t _BSoll is determined mathematically or empirically, for example, and stored in a memory 129 of the control device 116. On the other hand, the setpoint can t _Bsoll also be set dynamically. In other words, for example, the setpoint t _{BSoll is} continuously adapted to a machine _cycle of a machine system _interacting with the drive 100 and continuously read into the memory 129. From the setpoint for the movement time t _BSoll , a theoretical starting time T _Start (movement _start ) is set or calculated by the control _device 116, and a theoretical end time T _TE (theoretical end of movement) is calculated.

About the sensors 119, 120 is now in the first movement phase, the actual movement time the adjusting movement of the component between the end positions as actual value t _BIst detected. The detected actual value t _BIst is supplied to the electronic control device 116, whereupon a setpoint-actual comparison is carried out by a control unit 127 _comprising this between the determined movement time t _BIst and the defined movement time t _BSoll Fig. 16 seen.

If a control deviation (e) is calculated from the difference between the desired movement time t _BSoll predetermined for the first movement _phase and the actual movement time t _BIst determined from the first movement _phase , at least one manipulated variable is used by a controller 128 to control the control Switching element 109 formed. The manipulated variable is temporarily stored in the memory 129. For this purpose, the controller unit 127 has a computer module 130, in particular a microprocessor.

If the third movement phase is started, then the manipulated variable calculated by the first movement phase is read out of the memory 129 and adjusted according to the manipulated variable of at least one of the two temporally successive switching _times T _UZ1 , T _UZ2 , so that the control deviation (e) is corrected in the third movement phase is.

The first switching time T _UZ1 corresponds to the start time T _Start determined by the control device 116 or the higher-level control, in which the switching element 109 is controlled by a first control signal of the control device 116 or the higher-level control and energizing of the left control magnet 110 from the center position (rest position) to the Actuating position (A) is activated. In the actuated position (A), the pressure chamber 107 is subjected to system pressure, so that the component is moved in the direction of the left end positions. With the setting of at least one of the switching _times T _UZ1 , T _UZ2 , a control duration t _{SD of} a start pulse is changed. It proves to be advantageous if the first changeover time T _UZ1 remains unchanged with respect to the time axis and the control duration t _{SD of} the start pulse is set by changing the second changeover time T _UZ2 . The start pulse is predetermined by the rising edge in the first switching time T _UZ1 and the falling edge in the second switching time T _UZ2 . The pressure chamber 107 is subjected to system pressure over the control period t _SD , so that the component accelerates from standstill in the starting position or right end position to a _desired speed v _Soll and moves in the direction of movement - according to arrow 31- to its left end position becomes. In the second switching time T _UZ2 by the control device 116 or the higher-level control is given again to the left control magnet 110, a second control signal with which the left control solenoid 110 turned off and the switching element 109 from the operating position (A) into the central position (rest position) is adjusted , In the center position, the pressure chamber 107 is connected to the return port of the switching element 109 and thereby the originally pressurized pressure chamber 107 is vented.

The start pulse is followed within a time span t _{GB by a} plurality of short duration switching pulses t _SCH , by which the switching element 109 is actuated by the control device 116 or the superordinate control in intervals of successive intervals between the center position (B) and the actuation position (A). In other words, the switching element 109 is driven pulsed over the period t _GB and the pressure chamber 107 is applied over the duration t _SCH of each switching pulse with system pressure. The pulse pauses are in the Fig. 15 entered as periods t _P , within which the switching element 109 in the center position (B) remains and the pressure chamber 107 over the periods t _P of each pulse break is depressurized and the component solely on the basis of its inertia driving in the direction of movement - according to arrow 31 - moved on. Follows the pulse break a switching pulse, the pressure chamber 107 is applied over the periods t _SCH with system pressure and the component in turn accelerated over the duration t _SCH .

As in Fig. 15 registered, within the time period t _{GB of} the pulsed actuation of the switching element 109, the left control _magnet 110 by the control device 116 or the higher-level control via control signals at the switching times T _UZ3 ... T _UZn several times. In the switching time T _UZ3 , the left control _{magnet 110} receives a third control signal, with which the switching element 109 is actuated from its original center position (B) back to the operating position (A) and the pressure chamber 107 is acted upon. At the switching time T _UZn , the left control _{magnet 110} receives an nth control signal within the time period t _GB , with which the switching element 109 is actuated from its original actuation position (A) back into the middle position (B) and the pressure chamber 107 is vented. The duration of the pulsed actuation of the switching element 109 results from the time span t _GB between the second control or switching signal in the second switching time T _UZ2 and the control or switching signal for the n-th switching time T _UZn . At the end of the period t _GB , the theoretical end time T _{TE is} reached. The switching time T _UZN corresponds to the calculated end time T _TE , at which the component should have reached its end position.

To Fig. 15 However, in the first movement _phase , the left end position is not reached within the target movement time t _BSoll , but only to a later, determined by the approaching sensors 119 end time T _EE (corresponds to T ₂ ), which is after the theoretical end time T _TE . This circumstance can change the operating conditions and environmental conditions, for example, be changed by the additional load of the drive, the friction conditions occur. Based on the time difference .DELTA.t between the theoretical end time T _TE and the determined end time T _EE , the control deviation (e) is calculated and the at least one manipulated variable for setting at least one switching time T _UZ1 , T _UZ2 or the control duration t _{SD of} the start pulse is formed the switching element 109 is switched in the third movement phase. After the control duration t _{SD of} the start pulse is changed, the electronic control unit 127, in particular the computer module 130 of the control device 116, also calculates the pulse interval t _P between two successive switching pulses within the time period t _GB . These switching pulses follow the pulse pauses, which are defined by the time difference between two directly successive control signals at the switching _times T _UZ2, T _UZ3 to T _UZn . The duration t _SCH of the switching element 109 impressed switching pulses is preferably fixed depending on the type of drive and is stored in the memory 129. Likewise, the number of switching pulses within the time period t _{GB is selected} depending on the drive type and stored in memory 129. But it is equally possible that before commissioning of the drive 100 via an input device 131, in particular a computer (PC), or the higher-level control of the controller 116, the duration t _SCH and the number of switching pulses from the fitter is entered. In the Fig. 13 and 14 The controller 116 has the input device 131.

In practice, it has been shown that the number of switching pulses is decisively determined by the planned field of application. If, for example, a possible vibration-free positioning of the component in the end position or as smooth as possible adjustment of the component between the end positions must be ensured, the duration t _{SCH is} smaller and / or the number of switching pulses selected higher. As the number of switching pulses increases, the variations in the speed of movement of the component are minimized. Likewise, the must Duration t _SCH and / or the number of switching pulses to the adjustment of the component to be adjusted. For this purpose, the controller unit 127 may also have a dynamic learning mode (adaptive control) for setting the duration t _SCH and / or the number of switching pulses. For the time being, the component is controlled between the end positions by means of basic settings for the duration t _SCH and / or the number of switching pulses, and meanwhile the sensed oscillations are sensed. If the vibrations exceed a limit value, the duration t _SCH and / or the number of switching pulses are automatically adapted until the vibrations are within a permissible range and an optimum driving behavior of the component is achieved. Even during operation, an automatic adaptation can be maintained, that is, changes in sliding properties, masses, signs of aging, impact energy in the end position and the like can be continuously adapted to compensate by changing the duration t _SCH and / or the number of switching pulses become.

Thus, the computer unit 130 of the controller unit 127 can be used to calculate the time interval t _{P of} each pulse break after a calculation algorithm stored in the memory 129 and described below. $${\mathrm{t}}_{\mathrm{P}}\left[\mathrm{ms}\right]\mathrm{=}\frac{{\mathrm{t}}_{\mathrm{Bsoll}}\mathrm{-}{\mathrm{t}}_{\mathrm{SD}}\mathrm{-}\left(\mathrm{Number\; of\; switching\; pulses}•{\mathrm{t}}_{\mathrm{SCH}}\right)}{\mathrm{Number\; of\; switching\; pulses}}$$

Different speed profiles of the component are in Fig. 17 shown. If there is a long control period t _SD , the speed profile entered in full lines results, while the speed profile entered in dotted lines results for a short control time t _SD . As can be seen, the component reaches its maximum setpoint speed v _setpoint in a time span over the control duration t _SD . From the second switching time T _UZ2 within the time period t _GB , the component increasingly loses movement speed, so that it is moved with respect to the maximum target speed v _target reduced movement speed against the end position.

The speed drop Δv varies depending on the control period t _{SD of} the start pulse. If a high control deviation (e) occurs, and therefore the detected movement time t _{BIst is} higher than the set movement time t _BSoll , the control duration t _{SD of} the starting pulse is also increased, thereby increasing the component to a high movement speed in the first period accelerated. Accordingly, as the control duration t _{SD of} the starting pulse increases, the duration t _P of each pulse break is reduced uniformly, that is, the component is moved without drive over shorter intervals, as indicated in solid lines. If, on the other hand, the control duration t _{SD of} the start pulse is reduced, then the duration t _P of each pulse break is increased uniformly, that is, the component is driven without drive over longer intervals, as indicated in dashed lines.

The method according to the invention makes use of the knowledge that the ambient conditions, in particular the friction or aging phenomena during the non-moving movement of the component cause a targeted deceleration of the component on its adjustment, for example, from the right end position to the end position, so that the component gently against the final position is running.

If the speed drop Δv is too high, the time difference Δt increases. In order to prevent an unnecessarily high increase in the time difference .DELTA.t and thus the movement time of the component on its adjustment between the end positions, the theoretical end of movement at the end time T _TE by a monitoring device 132 of the control device 116, a monitoring signal S _Ü triggered with which a first time specified becomes. If this period has expired and the component is not yet in its planned end position, which is monitored by the sensor 119, the control device 116 the switching element 109 at a switching time T _UZA a Nachschaltsignal S _{NS is switched} on and the pressure chamber 107 over a period of time t _A. controlled with system pressure, so that the component moves in the direction of movement - according to arrow 31- towards its end position, pressed against them and kept positioned in this with a holding force. The time interval t _A results from the time difference between the switching time T _UZA the first movement _phase and the first switching time T _UZ1 or the start time T _start the second movement _phase in the opposite direction of movement - according to arrow 31 '. The Nachschaltsignal S _NS therefore corresponds to a Nachschaltimpuls. If the component is actually in its end position, the signal S _{2 is} triggered via the control edge 33 a at the sensor 119 arranged in the end position to be approached at the time T _EE or T ₂ (not registered). Please refer to the detailed description here Fig. 8 referred to, in which the waveform S _E2 is explained on the sensor 21 and can be transmitted in this embodiment for the sensor 119th Furthermore, it is possible that of the control device 116 or the higher-level controller, a second time period t _F from the time difference between the first measurement signal S ₁ and the last switching time T _UZn , therefore, when the switching element 109 from its operating position A in the rest position B is transformed , is evaluated. If the first period of time exceeds the second time interval (t _F ), then the follower signal S _NS is generated by the monitoring device 132 before the end of the first period of time and applied to the switching element 109, so that the component is acted upon at an early stage in the direction of movement - according to arrow 31- with system pressure becomes. Thereby, the actual movement time can be shortened when the target movement time T _{Bsoll deviates} from the actual movement time T _BIst .

As Fig. 15 shows in the third movement _phase , the control deviation (e) between the target movement time T _Bset and actual movement time T _{BIst is compensated} by the control period t _{SD of} the start pulse and the periods t _{P of} the pulse pauses are set so that the actual movement time T _are the target movement time T corresponds _Bsoll and the component within the predetermined target movement time T _Bsoll reaches the left end position. The control duration t _{SD of} the start pulse is extended and the time periods t _P shortened. If the component has reached its end position, a signal S _{2 is} triggered on the sensor 119 and supplied to the control device 116, whereupon the switching element 109 at a switching time T _UZA a Nachschaltsignal S _{NS switched} and the pressure chamber 107 over a period t _A with system pressure activated, so that the component is essentially pressed only against the end position and kept positioned in this with a holding force. Since there is no control deviation in the third movement phase, the adjustment of the control duration t _{SD of} the start pulse and the time intervals t _{P of} the pulse pauses remains for all subsequent movement phases in the same direction of movement, until a control deviation (e) is calculated by changing the friction conditions.

It is also advantageous if the switching pulses over the time period t _{GB are} regularly divided and the last switching pulse the switching element 109 just before the component reaches its end position, is switched. The component runs against the end position even before it has reached its maximum speed, as in Fig. 17 registered in dotted line. Thus, the speed impressed on the component via the last switching pulse at the switching-over time T _{UZn corresponds} to only a fraction of the speed which the component has in each case via the preceding switching pulses at the respective switching times is impressed, so that the end position is approached particularly gently. Conveniently, the control duration t _SD and the time t _GB or the time t _P of the pulse pauses so divided to the target movement time, that the switching time T _UZN with the switching time T coincides _UZA. As a result, the last switching pulse passes directly to the Nachschaltimpuls and the component is already driven over the last switching pulse against the end position and pressed against this with a holding force which is maintained by connecting the Nachschaltimpulses over the period t _A , as in the third Movement phase is entered. Since the component has reached the end position monitored by the sensor 119 at the theoretical end time T _TE , no monitoring signal S _{T is} triggered by the control device 116. The reset signal S _NS is triggered by the response of the sensor 119 after the component has reached the end position and fed to the control device 116.

It is understood that in the reverse direction of movement - according to arrow 31 '- a correspondingly reversed activation of the switching element 109 takes place, as in Fig. 15 registered for the second movement phase, wherein the corresponding measurement signals S ₁ , S ₂ are triggered by the sensor 120, the confirmation signal S _B and start signal S _start from the sensor 119. The switching element 109 receives at the time T _start the first control signal for the start of the movement of the component from its left end position to the right end position again from the control device 116 or the higher-level control. In this case, driven by the higher-level controller or control device 116 of the right control solenoid 110 to the first control signal and placed in the currentless state, so that the switching element 109 T at the starting time to _start the second phase of movement from the rest position to the in Fig. 14 registered operating position (C) is connected, in which the pressure chamber 108 is connected to the pressure supply unit 114 and pressurized with system pressure, while the pressure chamber 107 is connected via the pressure line 113 with a vent line 125. Also for this direction of movement, in the second movement phase of the control device 116, the control time t _{SD of} the start pulse and the time intervals t _{P of} the pulse pauses is calculated at a control deviation (e) and in the fourth _phase of movement preferably the second switching time T _{UZ2 of} the switching element 109 set accordingly ,

Of course, there is also the possibility in this embodiment that the pressure chambers 107, 108 are each controlled via a switching element 133, 134. These switching elements 133, 134 are preferably formed by 3/2-way valves. Such an embodiment is in Fig. 1 and 2 shown and the control method according to the invention can also be transferred to this embodiment. The control of the switching elements 133, 134 via the control device 116, which in turn is connected via a first control line 14 with a control magnet of the left switching element 133 and a second control line 15 with a control magnet of the right switching element 134. The associated _{timing diagram} with the switching positions S _SCH1 , S _{SCH2 of} the switching elements 133, 134 is in Fig. 18 shown.

Finally, it should be pointed out that the control device is suitable for processing both control methods according to the invention. For this purpose, the control and calculation algorithm of the two driving characteristics of the component are stored in the memory of the control device. After the first driving behavior - according to the explanations after the Fig. 1 to 12b - The component should be moved as quickly as possible between the end positions, whereas according to the second driving behavior - according to the explanations of the Fig. 13 to 18 - The component is to be moved at a targeted speed. The choice of driving behavior can be done in different ways.

In a first embodiment, the corresponding driving behavior is selected via an input and / or output device, in particular a computer (PC), or the higher-level control of the control device. For this purpose, a user program is opened and output to the input and / or output device before commissioning the drive and selected by the fitter the desired driving behavior for the adjustment movement of the component in a first direction of movement and in a direction opposite to this movement direction. With the choice of one of the driving behavior, the control device activates the control and calculation algorithm assigned to the corresponding control method and controls the drive in the manner described above. For example, the first driving behavior for the first movement direction and the second driving behavior for the other movement direction or either the first or second driving behavior for both directions of movement can be selected.

In a second embodiment, the driving behavior of the component is set dynamically. For example, based on a required cycle time of a composed of several drives handling system or a cooperating with the drive machinery the respective favorable driving behavior of the control device or the higher-level control specified. Suitably, the required cycle time is communicated by the higher-level, central control of the decentralized control device, which in turn makes the choice of the driving behavior based on the information of the available movement time. Thus, a current work process may require a particularly low cycle time, so that the drives of the handling system are controlled for both directions of movement after the first driving behavior. If the cycle time is less critical, but certain other parameters must be adhered to the handling system, for example, must be a vibration-free positioning of the drives, at least one of the drives according to the second driving behavior is controlled.

It should also be noted that the movable component can also be provided only with a control bar, which cooperates with a sensor arranged in the approaching end position. Such an embodiment is realized in those cases in which the component only has to be gently positioned against one of the end positions.

The embodiments show possible embodiments of the drive 1; 1'; 1 ", 100 and the method, it being noted at this point that the invention is not limited to the specifically illustrated embodiments thereof, but rather also various combinations of the individual embodiments are possible with each other and this possibility of variation due to the teaching of technical action by representational It is thus also possible to encompass all possible variants of embodiment which are possible by combinations of individual details of the illustrated and described embodiment variant, from the scope of protection.

For the sake of order, it should finally be pointed out that for a better understanding of the structure of the drive 1; 1'; 1 "; 100, this or its constituent parts were shown partly out of scale and / or enlarged and / or reduced in size Fig. 1 to 12 ; 13 to 18 shown embodiments form the subject of independent solutions according to the invention. The relevant objects and solutions according to the invention can be found in the detailed descriptions of these figures.

REFERENCE NUMBERS

1

drive

1'

drive

1"

drive

2

lifting cylinder

3

bulkhead

4

bulkhead

5

actuating piston

6

piston rod

7

fixed bearing

8th

pressure chamber

9

pressure chamber

10

switching element

11

switching element

12

control solenoid

13

control device

14

control line

15

control line

16

pressure line

17

pressure line

18

Pressure supply unit

19

signal line

20

signal line

21

sensor

22

sensor

25

control bar

26

control bar

27a

Schaltfahne

27b

Schaltfahne

28a

recessed groove

28b

recessed groove

29a

Endlagenabschnitt

29b

Endlagenabschnitt

30a

drilling

30b

drilling

31

movement direction

31 '

movement direction

32a

control edge

32b

control edge

33a

control edge

33b

control edge

34a

control edge

34b

control edge

36

switching element

37

control solenoid

40 '

actuator

40 "

actuator

41 '

guiding device

41 "

guiding device

42 '

guide carriage

42 "

guide carriage

43 '

frame

43 "

frame

44 '

fixed stop

44 "

fixed stop

45 '

shock absorber

45 "

shock absorber

46 '

fastening device

47 '

fastening device

48

handling system

50

arrow

51

vent line

52

arrow

53

output device

54

Storage

55

controller unit

56

computer module

70

block

71

block

72

monitoring device

73

step

74

block

75

step

76

comparator

77

regulator

78

step

79

comparator

80

regulator

81

step

82

step

83

block

100

drive

101

lifting cylinder

102

bulkhead

103

bulkhead

104

actuating piston

105

piston rod

106

fixed bearing

107

pressure chamber

108

pressure chamber

109

switching element

110

control solenoid

111

control line

112

control line

113

pressure line

114

Pressure supply unit

115

pressure line

116

control device

117

signal line

118

signal line

119

sensor

120

sensor

125

vent line

127

controller unit

128

regulator

129

Storage

130

computer module

131

Input and / or output device

132

monitoring device

133

switching element

134

switching element

Claims (32)

1. Method of controlling a fluid-operated drive (1; 1'; 1") with components which can be moved relative to one another, one of which components is moved via at least one switch element (10, 11; 36) in a first direction of movement (31) and in a second direction of movement (31') opposite the first direction of movement (31) between end positions and is decelerated as it is moved into at least one of the end positions, and control signals for timing the motion phase of the component which can be electronically switched via a switch flag (27a, b) are forwarded to a control system (13) respectively from a sensor (21, 22) disposed in the end position to ensure a smooth movement into the end position, and the switch element (10, 11; 36) is operated by the control system (13) on the basis of the control signals, and pressure chambers (8, 9) of the drive (1; 1'; 1") can be activated in opposing directions, characterised in that a first measurement signal (S₁) is detected by the switch flag-sensor arrangement during a first motion phase of the component shortly before the end position is reached at an instant (T₁) and a second measurement signal (S₂) is detected at a later instant (T₂), after which at least one period (t_1actual)) is calculated by the control system (13) from the time difference between the measurement signals (S₁, S₂), and a controller unit (55) of the control system (13) calculates at least one manipulated variable for at least one of two consecutive switching instants (T_UZ1, T_UZ2) of the switch element (10, 11; 36) by running a desired-actual comparison between a set period (t_1desired) and the detected period (t_1actual) to ensure a smooth movement into the end position, and this switching instant (T_UZ1, T_UZ2) of the switch element (10, 11; 36) is set on the basis of the manipulated variable in the other motion phase of the component in the same direction of movement (31, 31') following the first motion phase.
2. Method as claimed in claim 1, characterised in that a period (t_GD) is calculated by the control system (13) from the time difference between control signals at the switching instants (T_UZ1,T_UZ2) of the switch element (10, 11; 36) or is pre-set, and a deceleration phase set on the basis of the period (t_GD) is initiated at the first switching instant (T_UZ1) of the switch element (10, 11; 36) and is terminated at the second switching instant (T_UZ2) of the switch element (10, 11; 3 6), and a system pressure in the direction opposite the direction of movement (31, 31') of the component is increased in the pressure chamber (8, 9) originally without pressure during the movement of the component, and the system pressure acting in the direction of movement (31, 31') of the component is decreased in the pressure chamber (8, 9) which was originally pressurised during the movement of the component, and at the second switching instant (T_UZ1) of the switch element (10, 11; 36), a system pressure in the direction opposite the direction of movement (31, 31') of the component is decreased in the pressure chamber (8, 9) which was pressurised during the period (t_GD) and the system pressure acting in the original direction of movement (31, 31') of the component is increased in the pressure chamber (8, 9) which was without pressure during the period (t_GD).
3. Method as claimed in claim 1, characterised in that, during the first motion phase of the component, another period (t_3actual) is determined by the control system (13) from the time difference between the first measurement signal (S₁) and a control signal for the switch element (10, 11; 36) at the second switching instant (T_UZ2), after which manipulated variables to ensure a smooth movement towards the end position are calculated by the controller unit (55) of the control system (13) from a desired-actual comparison between a set period (t_3desired) and the determined period (t_3actual) for a first and second switching instant (T_UZ1, T_UZ2) of the switch element (10, 11; 36) respectively, and these switching instants (T_UZ1, T_UZ2) of the switch element (10, 11; 36) are set on the basis of the manipulated variables during the other motion phase of the component in the same direction of movement (31, 31') following the first motion phase if the determined period (t_3actual) deviates from the set period (t_3desired).
4. Method as claimed in claim 3, characterised in that a period (t_GD) based on the time difference between control signals at the switching instants (T_UZ1, T_UZ2) of the switch element (10, 11; 36) is set by the control system (13) during the first motion phase of the component, and the first and second switching instants (T_UZ1, T_UZ2) of the switch element (10, 11; 36) are shifted from the first measurement signal (S1) on the time axis by a constant time interval corresponding to the period (t_GD).
5. Method as claimed in claim 1, characterised in that a period (t_GD) is calculated from the time difference between control signals at the switching instants (T_UZ1, T_UZ2) of the switch element (10, 11; 36) by the control system (13) and changed, and to this end, the first switching instant (T_UZ1) of the switch element (10, 11; 36) in terms of timing is set by the controller unit (55) in the other motion phase of the component in the same direction of movement (31, 31') following the first phase motion, and the second switching instant (T_UZ2) of the switch element (10, 11; 36) in terms of timing is set on the basis of the calculated manipulated variable if the determined period (t_1actual) deviates from the set period (t_1desired).
6. Method as claimed in claim 2, characterised in that a re-set signal (S_NS) is generated by the control system (13) at the second switching instant (T_UZ2) of the switch element (10, 11; 36) and the switch element (10, 11; 36) is switched on, and the latter applies system pressure to the pressure chambers (8, 9) for a period (t_SCH2) so that system pressure is applied to the component in the direction of movement (31, 31') until it has safely reached its end position.
7. Method as claimed in claim 1 or 6, characterised in that a pre-control signal (Svs) is transmitted to the switch element (10,11; 36) by the control system (13) at the pre-control instant (Tvs), by means of which the pressure chambers operating at system pressure are vented by the switch element (10, 11; 36) before the component starts to move during the other motion phase in a direction of movement (31') opposite the direction of movement (31) of the first motion phase.
8. Method as claimed in claim 1, characterised in that a period (t₄) during which the component will remain in its end position is predetermined by the control system (13) at the instant (T₂) and a release signal is generated at the end of the period (t₄), by means of which or at a subsequent start time (T_start) set by the control system (13) or a higher ranking controller the switch element (10, 11; 36) is reversed in order to start the movement of the component in the other direction of movement (31') opposite the direction of movement (31) of the first motion phase.
9. Method as claimed in claim 1, characterised in that a period (t₅) is calculated by the control system (13) during the first motion phase of the component at the instant (T₀), based on the time difference between a control signal forwarded to the switch element (10, 11; 36) activating the component by the control system (13) or a higher-ranking controller at the start time (T_start and a start signal (S_start) is triggered after the component has started to move during the motion phase and is detected by a sensor (21, 22) disposed in the end position at the end where the movement starts, and the start time (T_start) at which the control signal is triggered and applied to the switch element (10, 11; 36) during the other motion phase of the component in the same direction of movement (31, 31') following the first motion phase is set on the basis of the calculated period (t₅).
10. Method as claimed in claim 1, characterised in that, taking account of the system properties of the other drive (1") actively connected to the drive (1; 1'), the control system (13) calculates an instant (T_R) at which a check-back signal (S_rück) is triggered and by means of which the other drive (1") is activated before, at the same time as or after the component of the first drive (1; 1') reaches the end position.
11. Method as claimed in claim 1, characterised in that a signal sequence of the sensors (21, 22) during the motion phase of the component between its end positions is evaluated by a monitoring system (72) of the control system (13) and the number of changes of state of a signal level between a high level and a low level is monitored.
12. Method as claimed in claim 11, characterised in that a threshold number of changes of state of a signal level between a high level and a low level is set by the control system (13), and a desired-actual comparison is run between a set period (t_1desired) and the determined period (t_1actual) during the first motion phase of the component if the determined number of changes of state exceeds the set threshold number of changes of state, and a manipulated variable for at least one of two consecutive switching instants (T_UZ1, T_UZ2) of the switch element (10, 11; 36) is calculated by the controller unit (55) to ensure a smooth movement into the end position on the basis of the desired-actual comparison between a set period (t_1desired) and the determined period (t_1actual), after which a period (t_GD) during which force will be applied to the component in the direction of movement (31') opposite its direction of movement (31) during the other motion phase of the component in the same direction (31, 31') following the first motion phase is increased on the basis of the manipulated variable if the determined period (t_1actual) drops below the set period (t_1desired).
13. Method as claimed in claim 11, characterised in that a threshold number of changes of state of a signal level between a high level and a low level is set by the control system (13), and a desired-actual comparison between a set period (t_1desired) and the determined period (t_1actaual) is run during the first motion phase of the component if the determined number of changes of state exceeds the set threshold number of changes or state, and in order to ensure a reliably smooth movement into the end position, a period (t_GD) during which force will be applied to the component in the direction of movement (31') opposite its direction of movement (31) during the other motion phase of the component in the same direction ofmovement (31, 31') following the first motion phase is reduced by the control system (13) on the basis of a weighting factor if the determined period (t_1actual) exceeds the set period (t_1desired).
14. Method as claimed in claim 11, characterised in that the determined number of changes of state of a signal level between a high level and a low level and a set minimum number of changes of state of a signal level between a high level and a low level are compared and evaluated by the control system (13), and an error message is forwarded to an output device (53) of the control system (13) or a higher-ranking controller if the determined number of changes of state falls below the set minimum number of changes of state.
15. Method as claimed in claim 1, characterised in that the period (t_GD) for reversing activation of the pressure chambers (8, 9) is monitored and an error message is forwarded to an output device (53) of the control system (13) or a higher-ranking controller if an upper time threshold for the period (t_GD) set by the controls system (13) is exceeded.
16. Fluid-operated drive (1; 1'; 1 ") for implementing the method as claimed in one of claims 1 to 15, with components which can be moved relative to one another, one of which components can be moved via at least one switch element (10, 11; 36) in a first direction of movement (31) and in a second direction of movement (31') opposite the first direction of movement (31) between end positions and is decelerated as it is moved into at least one of the end positions, and control signals for timing the motion phase of the component which can be electronically switched via a switch flag (27a, b) can be forwarded to an electronic control system (13) respectively from a sensor (21, 22) disposed in the end position to ensure a smooth movement into the end position, and the switch element (10, 11; 36) can be operated by the control system (13) on the basis of the control signals, and pressure chambers (8, 9) of the drive (1; 1', 1") are activated in opposing directions, characterised in that the moving component is provided with a control strip (25, 26) at oppositely lying ends in its direction of movement (31, 31'), which control strip (25, 26) constitutes the switch flag (27a, b) and comprises at least two control edges (32a, b, 33a, b) offset from one another in the direction of movement (31, 31') of the component so that, during the motion phase of the component, a first measurement signal (S₁) can be triggered by the first control edge (32a, b) within the active range of the sensor (21, 22) disposed in the end position towards which the movement is being effected at an instant (T₁) and a second measurement signal (S₂) can be triggered by the second control edge (33a, b) within the active range of the same sensor (21, 22) at a later instant (T₂), and the control system (13) has a controller unit (55) for calculating at least one manipulated variable for at least one of two consecutive switching instants (T_UZ1, T_UZ2) of the switch element (10, 11; 36) from a desired-actual comparison between a set period (t_1desired) and a determined period (t_actual) to ensure a smooth movement into the end position, and the switch element (10,11; 36) is provided as a means of setting at least one switching instant (T_UZ1, T_UZ2) on the basis of the manipulated variable in the other motion phase of the component in the same direction of movement (31, 31') following the first motion phase.
17. Drive as claimed in claim 16, characterised in that the control system (13) also has a monitoring system (72) for evaluating a signal sequence of the sensors (21, 22) during the movement of the component between its end positions or a period (t_GD) for the duration of which the pressure chambers (8, 9) are reversed.
18. Drive as claimed in claim 16 or 17, characterised in that the control system (13) also has an output device (53) for evaluating the signal sequence of the sensors (21, 22) or outputting an error message.
19. Drive as claimed in claim 16, characterised in that the control strip (25, 26) has a recessed groove (28a, b) disposed across a part of its thickness extending transversely to the direction of movement (31, 31'), by means of which the switch flag (27a, b) and an end position portion (29a, b) are separated from one another, and a width (B) of the recessed groove (28a, b) is at least between 1 mm and 5 mm, in particular between 2mm and 4 mm, for example 3 mm, and a lengthways distance between the control edges (32a, b, 33a, b) is at most between 4 mm and 15 mm, in particular between 5 mm and 12 mm, for example 9 mm.
20. Drive as claimed in claim 16, characterised in that the control system (13) and/or the at least one switch element (10,11; 36) is mounted on one of the components or is integrated in one of the components.
21. Drive as claimed in claim 1, characterised in that at least one of the end positions can be adjusted by changing the position of a fixed stop (3, 4; 44'; 44") and/or shock absorber (45'; 45") and/or a control strip (25, 26) and a sensor (21, 22) co-operating with it.
22. Method of controlling a fluid-operated drive (100) with components which can be moved relative to one another, one of which components is moved in a regulated manner via at least one switch element (109; 133, 134) in a first direction of movement (31) and in a second direction of movement (31') opposite the first direction of movement (31) between end positions, and electric control signals for timing the motion phase of the component to ensure a soft movement into the end position are forwarded to a control system (116) and the switch element (109; 133, 134) is operated by the control system (116) on the basis of the control signals, characterised in that a desired value for the movement time (t_Bdesired) during which the component moves from one end position into the other end position is set by means of the control system (116) or a higher-ranking controller and an actual value of the movement time (t_Bactual) is detected by the sensors (119,120) during the displacement of the component from one end position into the other end position, and a manipulated variable for at least one of two consecutive switching instants (T_UZ1, T_UZ2) of the switch element (109; 133, 134) is calculated from a desired-actual comparison between the set movement time (t_Bdesired) and the detected movement time (t_Bactual) by a controller unit (127) of the control system (116) to ensure a soft movement into the end position, and a control period (t_SD) predefined by the switching instants (T_UZ1, T_UZ2) is set by changing the switching instant (T_UZ1, T_UZ2) on the basis of the manipulated variable in the other motion phase of the component in the same direction (31, 31') following the first motion phase, and the component is firstly accelerated to a desired speed within the set control period (t_SD), after which the switch element (109; 133, 134) is operated on a pulsed basis for a period (t_GB) starting from the second switching instant (T_UZ2) until a theoretical final instant (T_TE) predefined by the set movement time (t_Bdesired).
23. Method as claimed in claim 22, characterised in that the switch element (109; 133, 134) is switched by means of the control system (116) or the higher-ranking controller by several consecutive switch pulses of short duration (t_SCH) within the period (t_GB), as a result of which a pressure chamber (107,108) of the drive (100) activating the component is pressurised at system pressure at intervals following one another at pulse pauses so that the component is moved in the direction of movement (31, 31') into the relevant end position at a speed of motion which becomes increasingly slower than the desired speed starting from the second switching instant (T_UZ2).
24. Method as claimed in claim 23, characterised in that the control system (116) or higher-ranking controller calculates a period (t_p) for the pulse pauses, during which the component is moved in the direction of movement (31, 31') in the direction towards the relevant end position on the basis of its own inertia without being driven.
25. Method as claimed in claim 23, characterised in that the number and/or duration (t_SCH) of the switch pulses is set by the control system (116) or higher-ranking controller.
26. Method as claimed in claim 23, characterised in that the number and/or duration (t_SCH) of the switch pulses is constantly determined by the control system (116) or higher-ranking controller in a dynamic learning mode in which the component is firstly moved into the end position in a controlled manner and, as it is so, a motion state is detected, such as the speed curve, the vibrations induced at the drive or the mechanical load on the drive due to impact stress as the component hits the end position, after which an optimum motion state is set at the drive (100) by constantly changing the number and/or duration (t_SCH) of the switch pulses.
27. Method as claimed in claim 22, characterised in that when the component arrives at its relevant end position within the set movement time (t_Bdesired) at the instant (T₂ respectively T_EE), a re-set signal is generated by the control system (116) and switched to the switch element (109; 133, 134) and the latter activates the pressure chambers (107, 108) at system pressure for a period (t_A) so that system pressure is applied to the component in the direction of movement (31, 31') and it is held in the end position by means of a retaining force.
28. Method as claimed in claim 22, characterised in that, in the event of a control variance (e) between the set movement time (t_Bdesired) and determined time (t_Bactual), a monitoring signal (So) is triggered by a monitoring unit (132) of the control system (116) at the theoretical final instant (T_TE) of the set movement time (t_Bdesired), by means of which a first period is predefined, and a re-set signal (S_NS) is triggered at the end of this period and switched to the switch element (109; 133, 134), and the latter activates the pressure chambers (107, 108) at system pressure for a period (t_A) so that system pressure is applied to the component in the direction of movement (31, 31') until it reaches its end position and it is then held in the end position by means of a retaining force.
29. Method as claimed in claim 28, characterised in that during the motion phase of the component, shortly before reaching the relevant end position, a first measurement signal (S₁) is detected at the sensor (119, 120) via a switch flag (27a, b) at an instant (T₁) and a second measurement signal (S₂) is detected at a later instant (T₂), and a second period (t_F) is determined from the time difference between the first measurement signal (S₁) and a control signal of the last switch pulse triggered at the switching instant (T_UZn), and the re-set signal (S_NS) is generated by the monitoring unit (132) before the end of the first period and switched to the switch element (109; 133, 134) if the first period exceeds the second period (t_F) so that system pressure is applied to the component early in the direction of movement (31, 31').
30. Fluid-operated drive (100) for implementing the method as claimed in one of claims 22 to 29, with components which can be moved relative to one another, one of which components can be moved via at least one switch element (109; 133, 134) in a first direction of movement (31) and in a second direction of movement (31') opposite the first direction of movement (31) between end positions, and control signals for timing the motion phase of the component to ensure a soft movement into the end position can be forwarded to an electronic control system (116) from sensors (119, 120) disposed in the end positions, and the switch element (109; 133, 134) is controlled by the control sys tem (116) on the basis of the control signals, characterised in that a desired value for the movement time (t_Bdesired) during which the component is moved from one end position into the other end position can be set by the control system (116) and an actual value for the movement time (t_Bactual) can be detected by the sensors (119, 120) as the component is moved from one end position into the other end position, and in order to ensure a soft movement into the end position, the control system (116) has a controller unit (127) which calculates a manipulated variable for at least one of two consecutive switching instants (T_UZ1, T_UZ2) of the switch element (109; 133, 134) by running a desired-actual comparison between the set movement time (t_Bdesired) and the detected movement time (t_Bactual), and the switch element (109; 133, 134) is provided as a means of setting a control period (t_SD) by changing the switching instant (T_UZ1, T_UZ2) on the basis of the manipulated variable in the other motion phase of the component in the same direction of movement (31, 31') following the first motion phase, and the component is firstly accelerated to a desired speed by an automatic control of the switch element (109; 133, 134) within the set control period (t_SD), after which the switch element (109; 133, 134) can be operated by the control system (116) on a pulsed basis starting from the second switching instant (T_UZ2) for a period (t_GB) until a theoretical final instant (T_TE) predefined by the set movement time (t_Bdesired)_.
31. Drive as claimed in claim 30, characterised in that the control system (116) also has a monitoring unit (132) for generating a monitoring signal (S_Ü) and evaluating a first and second period (t_F).
32. Drive as claimed in claim 30, characterised in that the control system (116) also has an input and/or output device (131) for setting the number and/or duration (t_SCH) of the switch pulses or outputting an error message.

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