JP5185809B2 - Method and apparatus for controlling and adjusting a servo-electric throttle cushion - Google Patents

Abstract

The invention relates to a method for controlling and regulating servo-electric die cushions (8, 9) on forming presses and to a device for carrying out said method. A stabile and precise operation in the phase of the force-regulated (15) drawing process and in all phases of the charge-regulated displacement (14, 16) of the cushion are possible due to the simple structure of the control and regulation and a reduced number of steps in the control and/or regulation operation. The conductive wave-regulated electronic curve disk regulation principle is combined with the force regulation in order to control and regulate the die cushion (8, 9), such that all displacement phases (14, 15, 16) of the die cushion, which are not in mechanical contact with the press slide, are controlled by electronic position-curve slides (12) during which the movements are in contact with the press slide due to force regulation with a path-dependent controlled force desired value profile.

Description

  The present invention relates to a method for controlling and adjusting or open-loop control and closed-loop control (Steerung / Regelung) of a servo-electric throttle cushion of a deformation press as described in the upper conceptual part of claim 1. The invention further relates to an apparatus for carrying out the method as defined in the upper conceptual part of claim 8.

US Pat. No. 5,435,166A discloses a diaphragm device that is provided in a table of a press and generates a cushioning force by a servo drive device. In this case, the servo drive device is coupled to the cushion plate via a gear and a rack. In this case, a plurality of servo drive devices that are mechanically connected to each other can act on one common pressure box, and one servo drive device is independent of other servo drive devices. It is also possible to act on one pressure box element of each of the multi-part pressure boxes. The servo motor is controlled by numerical control based on a position signal and a torque signal necessary for generating a squeezing force. In this case, feedback of the actual value of the cushion plate belonging to the servo motor or the diaphragm device can be performed in the control circuit as necessary.

  JP04172200A (Japanese Patent Laid-Open No. 04-172200) describes control for preliminary acceleration of a hydraulic throttle cushion. At that time, the preliminary acceleration is started at a predetermined press angle, and the target position is set by the calculation unit.

  The configuration, calculation, control type and in particular synchronization of the movement and force course of the throttling device during all periods of motion with the main and secondary movements of the slide, for example the handling movement, are described in both of these documents. Not.

  EP 0 566 390 B1 discloses another device for a throttle cushion that combines pneumatic and hydraulic pressure. In the case of this device, switching from position control to pressure control is performed by a switching signal related to the position between the period of preliminary acceleration and the throttle step. Apart from the period of pre-acceleration, there is no disclosure of another period with position control that is necessary for a closed motion cycle. Since the position control circuit for the pre-acceleration period is closed only via actual value feedback, the control quality of matching the throttle cushion speed to the slide speed is limited. Due to the position-related switching signal for switching from position control to force control, process-related variations can adversely affect the reproducibility of the pressure increase at the start of throttling. Due to the structure of the pneumatic / hydraulic throttle cushion, a separate control unit is required for each servo valve arranged corresponding to a separate hydraulic actuator for the pre-acceleration period and the throttle process period It is. Furthermore, activation control of the force target value profile for the possibility of fluctuating forces during the throttling process is not disclosed.

  The pressure box of the device, which is known from DE 1982 21 159 A1, provided in the table of a provider press, has a resistance formed against the downward movement of the slide on the cushion plate via the spindle / spindle nut system on the motor. It is operatively coupled so that it can be controlled by a motor. The tilting movement of the pressure box should be prevented by a drive motor and a driven motor which are electrically or mechanically connected in a slipless manner.

  In particular, a multipoint squeezing device and a one-piece pressure box, on which the individual pressure points on the one hand allow different force adjustments during the squeezing process and on the other hand should avoid the tilting of the pressure box as a result of eccentric loading. For use in the large press provided, the synchronous connection known from the prior art between the pressure points is not suitable.

  Furthermore, it is disclosed that the movement of the diaphragm device is synchronized on the one hand between the slide and the diaphragm device via an electrical shaft and on the other hand between a number of servo motors belonging to the diaphragm device. The required drawing force can then be adapted during the deep drawing process by changing the motor torque. The equipment required for this and the method steps required for control are not disclosed.

  DE 42 218 818 A1 has an object of replacing a mechanical cam for driving a parts conveying device in a forced control manner in a transfer press. For this purpose, the control of the movement of the parts transport device by means of a master axis is described for complete electronic synchronization with the main movement of the slide. The basis of this control is the principle of electronic cam control. The motion of the press slide is detected by one or two position detectors as a master axis, and the motion axis of the parts conveying device is controlled according to a motion function calculated in advance in relation to the master axis position.

  A similar principle is described in DE 19642962 A1 for a hydraulic press. In this press, a clock generator is used as a virtual master axis to control the slide motion as well as the motion axis of the parts transport device relative to the virtual master axis position.

The advantage of this principle is the possibility of position synchronization between the press slide and the parts transport device on the one hand and between the individual motion axes on the other hand in a multi-axis part transport device.
Since both last listed uses in the parts transporter do not include force control based on their function, their use is unsuitable for force controlled throttle cushions.

  JP-A-10202327 (Japanese Patent Laid-Open No. 10-202327) describes a controller for a press servo-electric throttle cushion. During the movement of the throttle cushion, switching from position control to force control is performed by a control deviation when a slide collides with the throttle cushion. Since the current threshold exceeded during the collision process is used as the switching criterion, impact force increases that occur as a result of time-delayed effects and are undesirable for high throttle part quality cannot be avoided.

The object of the present invention is to provide a simple structure for control and adjustment and a small number of steps in the control process or adjustment process, on the one hand during a force-controlled throttling process and on the other hand in a position-controlled cushioning period. It is to provide a method and apparatus for controlling and adjusting a press servo-electric throttle cushion that enables a stable and precise process with high control quality and reproducibility.

  According to the invention, this problem is solved by a method for controlling and adjusting a servo-electric throttle cushion having the features set forth in the characterizing part of claim 1. Further details of this method are described in claims 2-7. The method as defined in claims 1 to 7 is carried out by an apparatus having the features as defined in the features of claim 8. Claims 9 to 12 have a further advantageous configuration of the device.

  According to the method of the present invention that has solved the above-mentioned problems, there is provided a method for controlling and adjusting a servo electric throttle cushion of a deformation press, wherein the deformation press has an NC control device. The control device adjusts the position, speed and force of the servo motor or hydraulic cylinder formed as an actuator, and during the sliding motion, until the point of collision of the slide against the throttle cushion, it will be at the cushion position and at the current master axis position. The position control that obtains the target value from the position cam that is read out accordingly has an effect, switching to the force control at the point of collision of the slide with the throttle cushion, and from the point of collision of the slide with the throttle cushion to the lower reversal point Servo electric diaphragm cushions for deformation presses that force the force with the force target value read from the master axis position In addition to position control, the actual value of the encoder position is differentiated from the actual position value of the encoder, up to the point of impact of the slide against the throttle cushion during the sliding motion. Whether the switching between position control and force control or torque control is effected by evaluating the maximum control deviation of the position controller or speed controller at the point of impact of the slide on the throttle cushion. In the region from the abutment of the slide to the throttle cushion to the end of the joint movement with the slide. The progress at is above the cushion position forced by the slide, and the end of the joint movement with the slide from the point of collision of the slide with the aperture cushion. Depending on the driving type, even if the lower reversal point is exceeded, force control or torque control is performed to obtain the target value from the force target profile read according to the current cushion position, slide position or master shaft position, and Depending on the pre-selected operation type of the throttle cushion, switching to position control by the position cam at the lower reversing point or at the start of damping of the end position of the cushion rise, and this movement process continues periodically I tried to do it. In addition, before the start of the process, the movement of the throttle cushion can be determined in addition to the pre-acceleration period, with no locking at the lower position and with locking or pulling back, depending on the selected operating mode of the throttle cushion, The end position damping period with the protrusion of the cylinder, the cushion rising and the subsequent rest at the upper position is input in relation to the slide position or master axis position, calculated and as an electronic position cam in the NC controller As well as the desired force course in the throttle area is input in relation to the cushion position, slide position or master axis position, calculated and stored in the NC controller as a force target value profile. In addition, a force profile related to the position for raising the cushion in the operation type “without locking” is input and calculated in relation to the cushion position, the slide position or the master axis position, and NC is set as the force target value profile. It is advantageous if it can be stored in the control device. It is also advantageous to store in the NC controller the progress of the position cam above the cushion position forced by the slide position for the period of force control. It is also advantageous if the cam control device calculates, stores and reads out a target value for the position cam in relation to the master axis. It is also advantageous if the force target value controller calculates, stores and reads out a target value for the force target value profile in relation to the master shaft or cushion position. It is also advantageous if the position cam and the force target value profile can be stored in the control unit in the form of a table, a mathematical function or a combination of both.

  According to the configuration of the present invention that solves the above-described problems, an apparatus for controlling and adjusting a servo-electric throttle cushion of a deformation processing press, the deformation processing press having an NC control device, and the NC In the type in which the control device adjusts the position, speed and force of a servo motor or hydraulic cylinder formed as an actuator so that the movement and force course required for the throttling process occurs, the cam control device and The force target value control device is operatively coupled to at least one shaft control device, the shaft control device having a functional unit for switching the controller between position control and force control. . Furthermore, it is advantageous if the master axis for reading out the position cam is represented by an actual rotary position detector provided in the drive section of the press. It is also advantageous if the master axis for reading out the position cam is expressed by an actual position detector provided in the drive unit of the parts transport system. It is also advantageous if the master axis for reading out the position cam is represented by a rotary virtual master axis signal. In addition, the master axis is represented by an actual linear stroke pickup provided on the press slide, and the stroke pickup allows two unrelated and independent movement periods of the slide for the control functions “down” and “up”. It is advantageous if the position cam which can be switched in response to this can be read out. Also, the master axis for reading the position cam is expressed by an actual linear stroke pickup provided on the slide, and the output signal of the stroke pickup is changed or converted into a region for downward movement and an upward movement. It is advantageous to be divided into areas for

  In addition to the servo-electric drive, the method and apparatus have in mind a servo-hydraulic drive for the diaphragm cushion of the deformation press. In this case, the throttle cushion is used on the one hand in the table as a throttle cushion acting on the lower mold and on the other hand in the slide as a throttle cushion acting on the upper mold. The aperture cushion can be configured as a single point or multi-point aperture cushion.

  The core idea of the present invention is that, for the control and adjustment of the throttle cushion, the principle of electronic cam control controlled by the master shaft is combined with force control, and the mechanical contact of the throttle cushion with the press slide All motion periods that pass without control are controlled via an electronic position cam, while motion with contact with the press slide is controlled via force control with a force target profile that is controlled in relation to the stroke. It is in the point to be done.

  The advantage of this principle lies in the complete synchronization of the movement of the throttle cushion with respect to the sliding movement, which is also observed when the speed of the sliding movement changes and during an emergency stop, and for this purpose no special control functions are required. is there. The same can be said for the synchronization of the pressure points of the multipoint throttle cushion and the synchronization of the throttle cushion movement with respect to the parts conveying device that exists as necessary.

  What is important is the possibility of switching between position control and force control by simple control technical means. On the one hand, the switching can be carried out via a limit value switch which, for example, evaluates the control deviation when the slide abuts against the throttle cushion and activates the switching device for force control. On the other hand, switching between position control and force control can only be defined by the course of the position cam relative to the position of the slide. For example, when the cam passes the upper side of the slide position, the cushion position is forced by the movement of the press slide. In this case, the excessively increased output signals of the position controller and the speed controller cause a dynamic force limit, thereby switching to force control.

  The simple structure and functional form of control results in improved assumptions for an elaborate and reproducible course of the drawing process, as well as reduced labor during setup and maintenance.

EXAMPLES The present invention will be described in detail below with reference to examples. The affiliation drawing, that is, FIG. 1, is a diagram showing the structure of the multipoint throttle cushion,
FIG. 2a is a diagram showing an apparatus of a first configuration for controlling a servo-electric throttle cushion,
FIG. 2b is a diagram showing a second configuration of the device for controlling the servo hydraulic throttle cushion;
FIG. 3 shows a series of steps of a method for controlling a servo-controlled throttle cushion,
FIG. 4a shows an exemplary course of movement of the throttle cushion in the “locked” mode of operation in the lower position;
FIG. 4b shows an exemplary movement course of the throttle cushion in the “no rocking” mode of operation;
FIG. 5 is a block diagram for throttle cushion control having an electronic cam and partial switching to force control in a first configuration having a rotary master shaft;
FIG. 6 is a block diagram for throttle cushion control with an electronic cam and partial switching to force control in a second configuration having a linear detector on the slide and two cams. Yes,
FIG. 7 is a block diagram for throttle cushion control having an electronic cam in a third configuration having force limit control.

  FIG. 1 shows the structure of a servo-electric throttle cushion (Ziehkisen) 8 configured as a multi-point die cushion, with an electric cylinder 21 acting on a pressure box 2. The electric cylinder 21 is disposed in the inner region of the pressure box 2 and is supported in the press table 20. As a linear motion transducer, a spindle / spindle nut system 3, 23 is used in this configuration. The spindle nut 23 coupled to the pressure box 2 is not rotatable relative to the pressure box 2 and can move synchronously with the pressure box 2 in the axial direction. The associated spindle 3 is supported in a fixed manner in the axial direction so as to be rotatable in the press table 20. The end of the spindle 3 opposite to the spindle nut 23 is operatively connected to the servo motor 5 via a joint 24. The force is transmitted from the electric cylinder 21 to the thin metal plate holder 22 in the press tool through the pressure box 2 and the squeezing pin (Ziehstift) 25.

  The throttle cushion 8 may include a hydraulic cylinder 3 a instead of the electric cylinder 21 and may be configured as a servo hydraulic throttle cushion 9. A configuration in which the hydraulic cylinder 3a and the electric cylinder 21 are combined is also advantageous. In this case, the hydraulic cylinder 3a is responsible for the generation of force, and the electric cylinder or cylinders 21 are equipped with motion functions such as pre-acceleration, locking at defined positions, pulling back as required, protruding and raising the throttle cushion 8. Undertake.

  FIG. 2a shows the principle structure of the device with the servo-electric throttle cushion 8 schematically illustrated and described in FIG. Each servo motor 5 is equipped with one encoder 6. Position and speed are detected via the encoder 6. The cushion force is detected by one force pickup 4 for each pressure point. The force pickup 4 can be, for example, a piezoelectric or resistive strain pickup. As an alternative, the cushioning force can be detected indirectly via the motor current of the servomotor 5.

  The NC control device 59 has one axis control device 58 for each pressure point of the aperture cushion 8. The shaft control device 58 undertakes pressure point position control, speed control and force control, and generates an output for starting and controlling the servo motor 5 or the hydraulic cylinder 3a. The shaft control device 58 obtains the command amount from the cam control device 56 and the force target value control device 57. Both devices are controlled via a master shaft (Leitwell). In this case, the master shaft can be embodied by a “real”, ie real position detector, provided on the press slide, the press drive device or the drive device of the parts conveying system inside the press, or for example of a servo press It can be realized by a “virtual”, that is, virtual master axis signal from the control unit.

  The cam controller 56 generates a position target value for the axis controller 58 in connection with the master axis. In this case, the principle of an electronic cam (elektronics Kurvenschiebe) is used. In this case, a cushion position is assigned to each master axis position by a control table or a mathematical function. The force target value controller 57 generates a force target value profile for force control in the axis controller 58. Depending on the use and part-specific requirements, this is a force profile that is controlled in relation to a certain value or position for the throttling area and, if necessary, for raising the cushion in the drive type "no locking" Can be an additional value of.

  It can be seen from FIG. 2b how the servo hydraulic throttle cushion 9 can be controlled to start by this method. The movable pressure box 2 is driven by two hydraulic cylinders 3a. The pressure in the hydraulic cylinder 3a is controlled by a servo valve or proportional valve 5a. The position is detected by a linear stroke pickup 6a provided in the pressure box 2, and the force measurement is realized by a pressure pickup 4a provided in the hydraulic cylinder 3a. From the arrangement of the signal interface (dotted line), it can be seen how the servo hydraulic throttle cushion 9 can be combined with the NC controller 59 shown in FIG. 2a. The possibility of this combination can also be said for the configuration shown in FIGS. 5, 6 and 7 of the throttle cushion control. The functional forms of the axis controller 58 and the output amplifier are in this case adapted to the requirements of the hydraulic system.

  FIG. 3 shows the proposed method in the form of a flowchart.

  In the first preparation period 31, the desired part-specific and operation type-specific movement course of the throttle cushions 8, 9 is set. At that time, the control unit calculates an electronic position cam 12 including a target course of the cushion position 13 related to the slide position 11. In the second preparation period 32, the desired force course of the squeezing cushions 8, 9 during the squeezing process is set. At that time, the control unit calculates a force target value profile including a force course related to the slide position and / or the cushion positions 11 and 13. The position cam 12 and the force target value profile are stored in the control in the form of a table, a mathematical function or a combination of both.

  The order of both preparation periods 31, 32 can be arbitrarily selected as preparation for the original cycle, and both preparation periods 31, 32 are entered manually via a corresponding operating surface or stored. Can be called from the device. It is also conceivable to carry out both these steps for a new part while the movement cycle for the previous part is still being carried out.

  After the start signal 37, in a first method step 33, a periodic course of the functions of the throttle cushions 8, 9 starts depending on the type of operation and can also be seen from FIGS. 4a and 4b. Until the stage where the slide comes into contact with the aperture cushion, the cushion position 13 is influenced by the position control. The position control obtains the target value from a position cam 12 that is read according to the current slide position 11. As the position cam 12 elapses, the throttle cushions 8 and 9 are first held at their upper positions, and then preliminarily accelerated immediately before the slide collision.

  In the second method step 34, when the slide comes into contact with the throttle cushions 8, 9, the control is switched to the force control (Kraftregelung) or the torque control (Drehmentenregulating) with the first switching condition 38. The first switching condition 38 can be satisfied by a predetermined slide position 11, the achievement of a defined control deviation, or a defined course of the position cam 12 in the context of force limiting control. The organization of affiliation is shown in FIGS.

  In a third method step 35, force control or torque control is performed after the slide abuts the throttle cushions 8 and 9 until the joint movement of the slide and throttle cushions 8 and 9 ends. In the force control or torque control, the target value is obtained from a force target value profile read out according to the current cushion position 13 or the slide position 11.

  In the fourth method step 36, depending on the preselected operation type of the throttle cushions 8, 9, the position cam is again in accordance with the second switching condition 39 at the lower position or at the start of damping of the end position of the cushion rise. 12 is switched to position control. The second switching condition 39 may be satisfied by the achievement of a predetermined slide position 11 or cushion position 13 of a prescribed control deviation or by a predetermined course of the position cam 12 in connection with force limiting control. it can.

  Subsequently, the periodic movement course with the first method step 33 is continued. Depending on the selected operating type of the throttle cushions 8 and 9, depending on the course of the position cam 12, movement function, lowering or locking in the lower position, part protruding, cushion raising and subsequent rest in the upper position An end position attenuation 19 with is performed.

  The sequence of steps shown in FIG. 3 in the course of the function of the aperture cushions 8, 9 can be seen in the form of a graph from FIGS. 4a and 4b.

  FIG. 4 a shows a typical course of movement of the throttle cushions 8, 9 in the driving mode “with locking” in the context of the proposed method. In this driving mode, the cushion ascending is not performed immediately after passing the inversion point on the lower side of the slide, but the movement of the throttle cushions 8 and 9 is first locked, and the ascending is delayed with respect to the sliding movement in time. Done. The slide position 11, the cushion position 13 and the position cam 12 are shown as a course related to time or crank angle.

  In the first period 14, position control by the electronic position cam 12 is performed. In this case, the cushion position 13 controls the pause at the upper position and the preliminary acceleration of the throttle cushions 8 and 9 according to the position cam 12. This corresponds to the first method step 33 shown in FIG.

  At the collision point 17, switching to force control is performed according to the second method step 34 shown in FIG. In the subsequent second period 15, force control according to the prescribed force target value profile is performed in accordance with the third method step 35 shown in FIG. During this period, the position cam 12 can be disabled. The progress of the position cam is effective only during this period when switching to force control is realized according to the configuration shown in FIG. At that time, the progress of the position cam 12 must be above the cushion position 13 forced by the slide position 11.

  At the lower inversion point 18, the switching to the position control by the electronic position cam 12 is performed in the same manner as in the fourth method step 36 shown in FIG. The subsequent third time period 16 includes motor functions, lower position locking and cushion pull back, part overhang, cushion lift, end position damping and upper position rest. This process is repeated periodically in the first period 14 mentioned at the beginning. The motor functions mentioned are included in the course of the position cam 12 and are implemented by position control associated with the slide position 11 which serves as a master axis.

  From FIG. 4b it can be seen a typical course of movement of the throttle cushions 8, 9 in the driving mode “no locking” in the context of the proposed control method. Similar to FIG. 4 a, the slide position 11, the cushion position 13 and the position cam 12 are shown as a course of time or crankshaft.

  After a first period 14 and a second stage 15, each having a similar course as shown in FIG. 4a, the cushion lift is performed immediately after the lower turning point 18. In this case, the throttle cushions 8 and 9 follow the sliding motion without delay. Force control continues at the lower inversion point 18. For this purpose, the force target value profile includes one or more values that are set so that the throttle cushions 8 and 9 project the deformed part according to the upward movement of the slide. At the start of the end position attenuation 19, switching to position control is performed. As a result, the end position attenuation and the pause at the upper position are set by the position cam 12, and this process is repeated periodically.

  FIGS. 5, 6 and 7 show in block diagram form an example of the use and advantageous configuration of the proposed throttle cushion control with partial switching to electronic cam and force control.

  The first configuration shown in FIG. 5 is a cam control function 41 for calculating the position cam 12, storing and reading related to the master axis, and for calculating the force target value profile, storing and reading related to the position. The force target value control function 42 and the axis controller 58 are included. The axis controller 58 comprises three (closed loop) control circuits: a position controller 43, a speed controller 44 and a force controller 45, a switching device 49 for the controller target value, and an output amplifier 46. Yes. All three control circuits are closed by corresponding actual value feedback. The actual position value is provided by the encoder 6, the actual speed value is generated from the actual position value by the differentiating element 47, and the actual force value is detected by the force pickup 4.

  Here, the function progress is controlled as follows by a master shaft corresponding to the crank angle of the press.

  When the press slide moves from the upper reversal point to the collision point 17 with the aperture cushions 8 and 9, a position target value is continuously given to the position controller 43 by the cam control function 41. The position controller 43 is followed by a speed controller 44 and further controls the activation of the force controller 45 via the switching device 49. In this arrangement structure, three controllers connected in cascade function as a position control unit. As a result, the servo motor 5 that is controlled to start via the output amplifier 46 and the pressure box 2 that is operatively connected follow the position cam 12. . In this way, the first movement period of the stop cushions 8 and 9 including the pause at the upper position and the preliminary acceleration is controlled.

  When the slide comes into contact with the aperture cushions 8 and 9, the functional unit 55 for switching the controller becomes effective. This functional unit 55 consists in this configuration of a limit value switch 48 and a switching device 49 for the controller target value. At that time, the switching device 49 switches to force control by a limit value switch 48 that evaluates the control deviation at the collision point 17. Accordingly, the position controller 43 and the speed controller 44 are invalid, and the force controller 45 obtains the target value from the force target value control function 42. The force target value control function 42 continuously generates a target value by reading the stored force target value profile in relation to the slide position or the cushion position. In this way, the second period 15 of the throttle cushion 8, 9 from the collision point 17 to the end of the joint movement of the slide and throttle cushion 8, 9 is controlled.

  Subsequently, by means of the switching device 49, the position cam 12 is again at the position below the throttle cushions 8, 9 when the function is “locking” or at the start of the damping end position damping 19 when the function is “no locking”. Switch to position control by. The position control is active until the slide next comes into contact with the aperture cushions 8 and 9. As a result, the exercise cycle continues as described above.

  For a given use or hydraulic press, it may be necessary to detect the slide position 11 directly with a linear stroke pickup 7.

  FIG. 6 shows a second configuration of throttle cushion control using a linear stroke pickup 7 provided on the press slide as a master shaft. For the rotary position detector 1, the distinction between downward and upward movement is no longer possible directly by the master axis signal. For this purpose, two cams with a position cam 50 for the control function “downward” and a position cam 51 for the control function “upward” are used. The switching is performed by a switching device 53 that is controlled via a switching cam 52 generated by the rotary position detector 1. Alternatively, the switching may be performed by a control signal from a virtual master axis, a device for direction detection, or a progress control unit for slide motion. Other functional forms correspond to the first configuration shown in FIG.

  It is also conceivable that only one cam is used and the position signal to which the linear stroke pickup 7 belongs is switched or adapted by calculation.

  In the third configuration shown in FIG. 7, a device 54 for dynamic force limitation is used as the functional unit 55 for controller switching. This device limits the output signal of the speed controller 44 to the dynamically settable maximum value generated by the force target value control function 42. Thus, switching between position control and force control is defined only by the course of the position cam 12 relative to the slide position 11.

  When the position cam 12 passes below the slide position 11, the force limit is invalid and the system is in position control. As a result, the throttle cushions 8 and 9 follow the cam. On the other hand, when the position cam 12 passes above the slide position 11, the cushion position 13 is forced by the movement of the press slide. In this case, the output signals of the position controller and speed controller are extremely large, and force limitation is applied. Thereby, the system is in force control and the force target value profile is valid.

  For the first and second configurations, advantageously, controller switching controlled by additional elements is not necessary.

It is a figure which shows the structure of a multipoint aperture cushion. It is a figure which shows the apparatus of the 1st structure for controlling a servo electric type aperture cushion. It is a figure which shows the apparatus of the 2nd structure for controlling a servo hydraulic type aperture cushion. FIG. 5 shows a series of steps of a method for controlling a servo-controlled throttle cushion. FIG. 6 is a diagram illustrating an exemplary movement process of the throttle cushion in the “locking” driving mode at the lower position. FIG. 4 is a diagram illustrating an exemplary motion course of a throttle cushion in a “no rocking” mode of operation. FIG. 6 is a block diagram for throttle cushion control having an electronic cam and partial switching to force control in a first configuration having a rotary master shaft. FIG. 6 is a block diagram for throttle cushion control with an electronic cam and partial switching to force control in a second configuration having a linear detector and two cams provided on the slide. It is a block diagram for throttle cushion control which has an electronic cam in the 3rd composition which has force restriction control.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rotation type position detector as a master shaft 2 Pressure box 3 Spindle 3a Hydraulic cylinder 4 Force pickup 4a Pressure pickup 5 Servo motor 5a Servo valve or proportional valve 6 Encoder 6a Linear stroke pickup provided on the cushion 7 Master Linear stroke pickup provided on the slide as an axis 8 Servo electric type throttle cushion 9 Servo hydraulic type throttle cushion 11 Slide position 12 Position cam 13 Cushion position 14 First period 15 Second period 16 3rd 17 Collision point 18 Lower reversal point 19 Start of end position damping 20 Press table 21 Electric cylinder 22 Metal sheet holder 23 Spindle nut 24 Joint 25 Drawing pin 31 First preparation period 32 Second preparation period 33 First the method of Step 34 Second method step 35 Third method step 36 Fourth method step 37 Start signal 38 First switching condition 39 Second switching condition 41 Cam control function 42 Force target value control function 43 Position controller 44 Speed Controller 45 Force controller or torque controller 46 Output amplifier 47 Differentiating element 48 Limit value switch 49 Switching device for controller target value 50 Position cam for control function "down" 51 Position control for control function "up" Position cam 52 Switching cam 53 Switching device for cam 54 Dynamic force limit 55 Functional unit for controller switching 56 Cam control device 57 Force target value control device 58 Axis control device 59 NC control device

Claims (12)

A method for controlling and adjusting a servo electric diaphragm cushion of a deformation processing press, wherein the deformation processing press has an NC control device (59), and the NC control device (59) is formed as an actuator. The position, speed and force of the servo motor (5) or hydraulic cylinder (3a) adjusted are adjusted, and during the movement of the slide, the cushion position is reached until the point of impact (17) of the slide against the throttle cushion (8, 9). (13) is controlled by position control to obtain the target value from the position cam (12) read according to the current master axis position, and at the collision point (17) of the slide to the aperture cushion (8, 9), Switching to force control based on the evaluation of the maximum control deviation, force control is applied to the master axis position from the slide collision point (17) to the throttle cushion (8, 9) to the lower inversion point. A method for read to perform the force target value is, to control and adjust the servo electric throttle cushion deformation pressed from,
In the first method step (33), during the movement of the slide, the cushion position (13) is additionally added to the position control up to the point of impact (17) of the slide against the throttle cushion (8, 9). Control by speed control to obtain the actual value by differentiation from the actual position value in (6),
In a second method step (34), switching between position control and force control or torque control at the point of impact (17) of the slide on the throttle cushion (8, 9) is performed by the position controller (43) or Whether the speed controller (44) evaluates whether or not the control deviation, which is the deviation between the actual value of the throttle cushion (8, 9) or the actual value of the throttle cushion (8, 9) and the target value, is maximum,
Or by means of a dynamic force limit (54) that limits the output signal of the speed controller (44) to the maximum value that can be dynamically set by the force target value control function (42) . In the latter case, the position cam (12) position progresses in the region from the contact of the slide to the throttle cushion (8, 9) to the end of the joint movement with the slide. , Above the cushion position (13) forced by the slide,
In the third method step (35), from the point of impact (17) of the slide to the throttle cushion (8, 9) until the end of the joint movement with the slide, in the "no locking" mode of operation, the lower inversion Even if the point is exceeded, force control or torque control is performed to obtain the target value from the force target profile read according to the current cushion position (13), slide position (11) or master axis position, and the fourth method In step (36), the position cam at the lower reversal point (18) in the "with locking" driving mode or at the start of the end position damping (19) of the cushion rise in the "no locking" driving mode. Switching to position control according to (12) is performed, and thereafter, all these movements of the throttle cushion (8, 9) are periodically continued. A method for controlling and adjusting a servo-electric throttle cushion of a deformation press.   Before the start of the first method step, during the first preparation period (31) and the second preparation period (32), the movement of the throttle cushion (8, 9) is reduced in addition to the preliminary acceleration period. Depending on the selected type of operation of the cushion (8, 9), there is no locking and locking or pulling in the lower position of the throttle cushion (8, 9), the protrusion of the baht, the cushion lift and the throttle cushion (8, 9) 9) The period of end position attenuation (19) with subsequent rest at the upper position of 9) is input based on the slide position (11) or master axis position, calculated and electronic position cam (12) Stored in the NC controller (59) as well as the desired force course in the throttle area based on the cushion position (13), slide position (11) or master axis position. Methods for, and stored in the NC control device (59) in a calculated vital force target value profile, according to claim 1, to control and adjust the aperture cushion servo electric deformation processing press.   A position-based force profile for raising the cushion in the driving mode “no locking” is input and calculated based on the cushion position (13), slide position (11) or master axis position, and a force target value profile A method for controlling and adjusting a servo-electric throttle cushion of a deformation press according to claim 2, which can be stored in the NC controller (59) as   3. The course of the position of the position cam (12) above the cushion position (13) forced by the slide position (11) for a period of force control is stored in the NC controller (59). A method for controlling and adjusting a servo-electric aperture cushion of a deformation press as described.   The servo-electric throttle cushion of the deformation working press according to claim 1, wherein the cam control device (56) calculates, stores and reads out a target value for the position cam (12) based on the master axis. Method for controlling and tuning.   2. The deformation according to claim 1, wherein the force target value controller (57) calculates, stores and reads out a target value for the force target value profile (42) based on the master shaft or cushion position (13). A method for controlling and adjusting a servo-electric throttle cushion of a processing press.   3. The servo-electric throttle cushion of a deformation press according to claim 2, wherein the position cam (12) and the force target profile can be stored in the control in the form of a table, a mathematical function or a combination of both. Method for controlling and tuning. A servomotor (5) or hydraulic pressure device for controlling and adjusting a servo-electric throttle cushion of a deformation press, wherein the deformation press is formed as an actuator for driving the throttle cushion (8, 9). An NC controller (59) for adjusting the position, speed and force of the cylinder (3a) is provided, and the NC controller (59)
At least one axis controller (58) for driving the actuator;
A cam control device (56) for forming a position target value, which is operatively coupled to the shaft control device (58);
A force target value control device (57) for forming a force target value, which is operatively coupled to the axis control device (58);
The axis control device (58) has a functional unit (55) for switching the controller between position control and force control,
Or functional units for the controller switching (55) has a maximum limit switch for evaluating the control deviation of the position controller (43) or speed controller (44) (48), or has a device for dynamic force limit (54),
A device for the dynamic force limiting (54) is operatively coupled in control technology to the force target value control function (42) and the speed controller (44). Controlling and adjusting the servo-electric throttle cushion of the deformation press, characterized in that the output signal is limited to the dynamically settable maximum value formed by the force target value control function (42) Device to do. Based on the position detected by the position detector provided in the driving portion of the part carrier system (1), a cam control device (56) that are controlled, according to claim 8, the servo electrical of deforming the press A device for controlling and adjusting the aperture cushion. Based on the position detected by the position detector of the rotary type, a cam control device (56) that are controlled, according to claim 8, deforming the press servo electric controls the aperture cushion and adjusting an apparatus for . Based on the position detected by the linear stroke pickup (7) provided on the slide, the cam control device (56) is controlled , and the stroke pickup (7) controls the control functions "downward movement of the slide" and " 9. Servo electric type of deformation press according to claim 8, wherein two unrelated, position cams (50, 51), which can be switched according to the duration of the slide movement, are selectable for "upward movement of the slide". For controlling and adjusting the diaphragm cushion of Based on the position detected by the linear stroke pickup (7) provided on the slide, the cam control device (56) is controlled , and the output signal of the stroke pickup (7) is switched or converted to change the slide. 9. The apparatus for controlling and adjusting a servo-electric throttle cushion of a deformation press according to claim 8, which is divided into an area for downward movement and an area for upward movement of the slide.

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