WO2016096469A1

WO2016096469A1 - Method and system for calibrating the tong pressing force of an automatically actuatable pair of manufacturing tongs

Info

Publication number: WO2016096469A1
Application number: PCT/EP2015/078599
Authority: WO
Inventors: Franz Pecher
Original assignee: Kuka Roboter Gmbh
Priority date: 2014-12-19
Filing date: 2015-12-03
Publication date: 2016-06-23
Also published as: DE102014226655A1; EP3233359A1; CN107249829A

Abstract

The invention relates to a method for calibrating the tong pressing force of an automatically actuatable pair of manufacturing tongs (11), in reverse mode, said tongs comprising two tong halves (14, 16) which are mounted to be adjustable relative to one another and each have a tong tip (13a, 13b), in order to generate a tong pressing force, and said tongs comprising a drive (20) designed to move at least one of the tong halves (14, 16) so as to build a tong pressing force between the two tong tips (13a, 13b), the drive (20) being able to be driven automatically in a position-controlled manner such that a target tong pressing force is actuated by automatically setting a target drive position, associated with said target tong pressing force, for said drive (20) by means of a closing movement of the tong halves (14, 16). The invention also relates to an associated method for automatically actuating a pair of manufacturing tongs (11) in reverse mode, and to a system of a pair of welding tongs, clinching tongs, crimping tongs and/or a gripping tool with a control device (10).

Description

Method and system for calibrating the forceps force of an automatically controlled manufacturing tongs

The invention relates to a method for calibrating the forceps force of an automatically controllable production tool in the reversing operation, which has two mutually adjustable mounted, each having a pair of pliers tip pliers halves for generating a pliers pressing force, and having a drive which is adapted to move at least one of the pliers halves, in order to build a pincer pressing force between the two pliers tips, wherein the drive can be driven position-controlled automatically, such that a desired pliers pressing force is controlled by automatically adjusting ei ^¬ ner the target pliers pressing force associated target drive position of the drive by a closing movement of the pliers halves. The invention also relates to an associated method for the automatic control of a production tongs in reversing operation and a system of welding tongs, a clinching tongs, a crimping tool, and / or a gripper tool with a control device.

DE 44 32 573 C2 discloses a method for controlling the pressing force of a resistance welding machine, which is equipped with a numerically controlled electric motor and a screw drive, in which it may be necessary to ensure in certain phases of the welding process, that the welding electrodes on the workpieces to be welded exert a predetermined force, against a Schweißpro- the electric motor via the screw drive and the welding ^¬ ßelektroden process exerts sequentially two different forces on the workpieces, the associated angle of rotation will be indicative ^¬ net, and the spring constant of the power transmission structure of the welding machine is determined from these values by means of which desired a unique relationship between each during each phase of the subsequent welding process ^¬ th force and the corresponding angle of rotation to be performed by the electric motor.

The object of the invention is to be able to adjust the forceps force in a reverberating operation more accurately in a manufacturing tongs, which has two mutually adjustable mounted pliers halves, which are to be adjusted by a position-controlled drive against each other. The object of the invention is achieved by a method for calibrating the forceps force of an automatically controlled manufacturing pliers in reversing, which has two mutually adjustable mounted, each having a pair of pliers tip pliers halves for generating a pliers pressing force, and having a drive which is formed at least one of To move pliers halves to build a forceps force between the two pliers tips, the drive can be driven position-controlled automatically, such that a desired pliers pressing force is automatically controlled by automatically setting one of the desired forceps force associated target drive position of the drive by a closing movement of the pliers halves comprising the steps of: - positioning a pressure force-measuring device between the two open forceps halves as a normal force measuring for measuring the tongs pressing force Zvi ^¬ rule the two tongs tips; - closing the opened position pincers by controlled movement of the drive in a start-drive position of the drive, in which the Zangenspit ^¬ zen of the two pincers one of the start drive position associated with start-target Apply forceps press force to the pressure force measuring device;

Reversing the closed pliers halves by position controlled movement of the drive in a ge ^¬ genüber the start target tongs pressing force kraftredu ^¬ ed target driving position of the drive, in which the tongs tips of the two pincers associated with one of the target driving position of the actuator, opposite the start command Pliers press force-reduced target setpoint gun force is to apply to the Druckkraftmessvorrich ^¬ tion;

Measuring a target-actual gun force in the force ^¬ reduced target drive position of the drive by the pressure force measuring device;

Saving the target-actual gun force associated with the force-reduced target drive position of the drive.

Under a reversing a drive of the drive is understood that corresponds to an opening movement of the clamp halves, wherein the pincers are not completely geöff ^¬ net, but the pincers only be adjusted such that the forceps tips on an interposed, to be pressed part, such as two under Pressing force to be welded sheets, starting from a momentarily exercised ^¬ high pressing force are brought into a state in which exert the pliers halves a relation to the high pressing force reduced pressing force on the part.

The drive can be in particular an electric drive. This can have at least one electric motor and at least one associated power electronics. The motor and the power electronics can be components of a position-controlled electric drive. The position-controlled drive may include a drive controller, which is designed to control according to the engine due to an input, such as a predetermined position value, an angle value and / or egg ^¬ nes incremental value so that the motor shaft of the corresponding position (number of revolutions and the angular position) occupies. The motor shaft can be connected to a spindle of a gear associated with the production tool, which converts the rotations of the motor shaft into an opening movement or a closing movement of the pliers halves of the production tool.

In the itself, for example, from DE 44 32 573 C2, known methods to build a pressing force on a component between the pliers tips of the pliers halves, a fully open manufacturing gun is closed around the component and gradually built an increasing pressing force by the drive in a forward operation is brought to a pressing force associated drive position. Between drive ^¬ position and pressing force can, for example, according to DE 44 32 573 C2 a linear relationship exist. However, this relationship can be faulty. In that regard, the present invention un ^¬ ter the target tongs pressing force that the pressing force hen to be understood that in accordance with the assumed linear relationship with an associated drive position, the target driving position, non-reversing by driving the actuator with the target value, the target drive position in one, ie closing operation of manufacturing tongs is to be built.

The pressure force measuring device may be, for example, a load cell, a piezoelectric element, a load cell or the like. The pressure force measuring device can be used to form a As accurate as possible Kraftmessnormals be a calibrated pressure force ^¬ measuring device, in particular calibrated load cell.

In a reversing operation according to the invention, a high pressing force is reduced to a lower pressing force, without the pliers halves being completely opened and closed again. It is only the drive position of the drive from a starting driving position, in which the production pliers, brought to the high pressing force, that is, the start target exerts tongs pressing force in a power-reduced target driving position of the drive, in which the Ferti ^¬ supply pincer the lower pressing force, that is, to have the target setpoint gun force. The invention is now concerned with the problem that when using the linear relationship between the drive position and the forceps force in a reversing operation known from a forward operation of the production gun, ie a non-reversing, ie closing operation of the production gun, significant deviations of the actually exerted Target actual plier press force of the desired target plier press force supplies. According to the invention, therefore, the actual target-actual gripper pressing force ge ^¬ measured and derived from a new context, on the ^¬ sen basis in a reversing when specifying only a target drive position on the drive an improved, ie behaf ^¬ tete with a lower force Zangenpresskraft-deviation value Target actual forceps pressing force on the production tongs can be ^¬ sets.

In summary it can be said that the tongs pressing force deviation, that is the error of the actually set target actual tongs pressing force to the desired target setpoint tongs pressing force is greater, the higher the output ^¬ pressing force, that is, a start actual tongs pressing force is from which the forceps force is reduced. The error manifests itself in relation to the desired or assumed one Nominal forceps force to low target actual forceps force. It can also be said that the higher the reduction of the initial pressing force, ie, the jump in magnitude from the start actual, the greater the pincer force deviation, ie, the error of the actual set target pincer pressing force to the desired target pincer pressing force Pliers press force is in the force-reduced target target forceps press force. In other words, the higher gear pressing force the off ^¬ and / or the greater the Kraftreduktionsbe- is carrying, the more causes the saved by the tongs pressing force potential energy in the production pliers, that the forceps halves are opened more than required and resulted in too low a set reduced target actual forceps force.

The production pliers can be for example a welding gun, egg ^¬ ne clinching pliers or crimp tool. However, a gripper tool or a gripper, in particular for assembly in the context of the production of a product can be understood as manufacturing tongs. Each pliers half has a pliers tip.

The two forceps tips can be moved toward and away from each other by moving either a single or both forceps halves. To move one or both Zangenhälf ^¬ th, the position-controlled drive may be provided for hen, for example, comprises an electric motor and a transmission. The electric motor can be controlled or regulated by means of a drive control.

By means of a method according to the invention, a calibration and / or an automated activation of the production tongs in reversing operation takes place in particular without force sensors, ie without the use of a separate force sensor. That is, the manufacturing gun may be formed without a separate force sensor, which would otherwise be required for detecting a gun pressing force. These and other aspects of the invention are further described below, sometimes also in other words. Servo-motor manufacturing tools, in particular welding tongs, use almost exclusively rotary motors whose rotary motion is transformed by means of a gear into a linear movement of the movable nipper tips, in particular of electrodes. In the spindle gearboxes used in this case, the usual gear stick-slip effects and a gear play occur. These effects can be prevail ^¬ if the manufacturing tongs or the drive or the engine has its own force or torque sensor. If, for cost reasons, however, a sensorless production quill is to be used, then these effects must be eliminated or mastered in order to avoid unduly high force fluctuations.

The influence of stick-slip effects is minimized when the manufacturing gun is operated position-controlled, ie it is approached to the desired target force corresponding position of the engine. One now but trying to drive power profiles in which the movement of the motor at least once reversed significantly, it is first built up a certain force and there ^¬ by the power by a defined Delta reduced etc., then makes the backlash and with this method Similar effects, for example, in the bearings of the production tongs, as well as in the mounts of the engine noticeable in that the reduced forces have a significantly higher deviation from the desired force than is permissible. Typically, smaller forces set in than expected, that is, the manufacturing tongs are too relaxed. This effect can be countered by a gear backlash compensation, which, when reversing, includes a previously, partly machine-specific, specific position delta, the clearance, into the target position after reversing as a correction offset. This works very well for unloaded transmissions, but for transmissions operating against external forces and / or torques, the offset to be corrected still scales with these forces and / or moments, so that the game offset still has a linear relationship to the desired target force must be adjusted.

For the calibration of the clearance correction is compared which force values set in a calibrated dynamometer between the pliers tips of manufacturing tongs when one and the same target force is once approached directly and once after Re ^¬ production of a higher force. These two force values are subtracted from each other and the delta of the force is then converted with the help of the known spring constant, also called deflection, into a position value which is then to describe the gear play.

Position offset = ((force_direct - force_after_reduction) * path_pro_force Inventive measurements showed that it was a linear

Relationship between the necessary for the game correction position offset and the desired target force of the welding tongs ^¬ gives. Further, more detailed measurements showed that this is not sufficient to describe or compensate for all effects occurring during reversing.

According to the invention, it should be noted that the deviation of the force also scales with the force delta between a first and a second power stage. If one carries the position offsets correlating to these force deviations, the game, sets above the target forces and by the points Regressi ^¬ onsgeraden, we obtain a family of curves increasing with the force Delta. This shows that the regression lines can be laid with sufficient accuracy through the zero point without the inclines of the lines changing too much. This simplifies the white ^¬ direct modeling of the effect according to the invention considerably.

Now you wear on the slopes of the curves on the power deltas, one also recognizes a linear From ^¬ dependence. However, this can only be described sufficiently accurately by the slope and offset, since the offset can already account for 20% of the effect. The gradients of the family of curves and the parameters of the regression line for describing the gradients of the family of curves can be determined with the usual mathematical methods. Based on this knowledge can be the correction offset that must be open on the target position of the clamp for the reduced power level ^¬, fully describe mathematically position correction = ((game factor * power reduction) + games Offset) * target force

This procedure describes the passing of a production pliers on ^¬ effects without modeling in detail since it is superimposed type-setting, games and elasticity effects throughout the mechanics of production pliers and Zangenmo ^¬ tors.

If no pure position control is used for the production tongs, but the force of the tongs over the delta between see current position and detected contact of the electrodes with the component or with each other simulated using the spring constants of the mechanics, so make sure that you have to consider the contact position values for the calculation of the position offset.

This results in the following formula:

Position Offset = (((Istkraft_l * Weg_pro_Kraft) +

Zero_position) - contact_position_l) - (((actual_power_2 * path_pro_power) + zero_position) - contact_position_2)

Istkraft_l = force measured with external force gauge

(Power applied directly)

Istkraft_2 = Force measured with external dynamometer

(after power reduction)

Weg_pro_Kraft = Linear factor from the path / force Zangenkalib ^¬ turing

Zero_position = offset position value from the path / force Zan ^¬ genkalibrierung

A method comprising the step of determining a force press force deviation value from the difference between the target pressure force and the measured force value force.

A method comprising the step of multiple carrying out the procedure as described, with different start target tongs pressing force values, in particular with different starting target tongs pressing force values in steps equal steps distance and storing in each case one associated with the jeweili ^¬ gene start target tongs pressing force value pliers Press force deviation value per start-set gun force value. A method, comprising the step of executing the method multiple times as described, with different force-reduced target drive position values of the drive, in which the tong tips of the two tong halves have a target force assigned to the respective target drive position of the drive and reduced in force relative to the start-target forceps force. Target gun force is to apply to the pressure force measuring device, in particular with different kraftredu ^¬ ed target drive position values of the drive in stages equal pitch and the storage of each of the respective target drive position value associated Zangen- press force deviation value per target drive position value.

A method comprising the step of determining a respective one of each pliers pressing-force deviation value supplied ^¬ associated drive position deviation value, in particular on the basis of a linear relationship of the various drive positions of the drive and the associated target tongs pressing forces during the closing of the pliers halves.

A method comprising the step of linearly interpolating between a plurality of vertices of the drive position deviation values resulting from the plurality of different target pressure force values and / or storing linearly interpolated intermediate values, in particular in the form of a table or function, for reversing drive the manufacturing tongs a required, the desired start-Zangenkraftkraftwert zugeord ^¬ neter drive position deviation value is shown.

A method for the automatic control of a production gun in reversing operation, which has two mutually adjustable mounted, each having a pliers tip comprising pliers halves for generating a pliers press force, and having a drive which is formed at least one of To move pliers halves to build a pincer pressing force between the two pliers tips, the drive can be driven position controlled automatically, such that a desired pliers pressing force by automatically adjusting ei ^¬ ner the desired pliers pressing force associated target drive position of the drive by a closing movement of the pliers halves is controlled, comprising the steps:

Specifying a target-target-forceps press force, which is gerin ^¬ ger, as a momentarily exerted by the manufacturing tongs Actual tong press force;

Determining one of the target set point tongs pressing force applied ^¬ associated target driving position of the drive, taking into account Antriebspositions- deviation values which are obtained as described for a method of calibrating the tongs pressing force, in particular intermediate values of ei ^¬ ner table or according to a function that are generated due ^¬ position of drive position deviation values, a method for calibrating the tongs pressing force as described;

Reversing the closed pliers halves by position-controlled movement of the drive in the ^¬ be determined target drive position.

A method in which, for determining the target drive position of the drive, a relationship between the setpoint gun pressing force and the associated setpoint drive position of the drive is used for activating a closing movement of the tong halves, and from this context, an objective assigned to the target setpoint gun force is used. Target drive position is determined and corrected by the specific drive position deviation value, and on the Based on a reversing movement of the pliers halves is driven to adjust the target set plier press force.

System of a welding gun, a clinching pliers, a Crimpzan- ge, and / or a gripping tool and a control device for automatically moving the welding gun, the clinching pliers, the crimping tool, and / or the gripping tool, which control ^¬ device is set up, a method as described to perform.

System, wherein the control device comprises a memory in the drive position deviation values, insbesonde ^¬ re intermediate values, obtained according to a table or according to a functi ^¬ on, the force for a method of calibrating the Zangenpress-, as described, are stored and this drive position deviation values, in particular Zvi ^¬ rule values from the memory for performing a method for automatically controlling a production pliers, as described, are available.

Specific embodiments of the invention are explained in greater detail by ^¬ following description with reference to the accompanying figures. Concrete features of these exemplary embodiments, regardless of the specific context in which they are mentioned, if appropriate also individually or in combination, may represent general features of the invention.

Show it:

Fig. 1 is a schematic representation of a welding gun as an exemplary embodiment of a Ferti ^¬ supply tong, 2 shows an industrial robot with a multiple limbs and joints having robotic arm,

3 shows a schematic diagram of measured target / actual gun force forces achieved in a reversing operation from associated start / target gun pressing forces in four different target / target gun press forces, FIG. 4 shows a schematic diagram of drive position deviation values as a function of dependency various start-target forceps force and force-reduced target force forceps forceps, and

5 shows a schematic diagram representation of gain factors of the drive position deviation values as a function of different force reduction values from the start-set forceps force forces into the target target value.

Pliers press forces.

1 shows, as an example of a production tongs 11, a welding tongs 12 with two tongs halves 14, 16. At their front end, the tongs halves 14, 16 each have, for example, one electrode as an example of a tongs tip 13a, 13b. As shown in FIG. 1, the first ^collet half 14 is movably mounted about a pivot axis 18. The second tong half 16 may be fixed or movable. To the

Pivoting the first pliers half 14 about the pivot axis 18 relative to the second pliers half 16, a position ^¬ controlled drive 20 is provided. The drive 20 is at ^¬ example an electric drive, such as an electric motor. Means of the drive 20 can be moved to the second tong half 16 between a geschlosse ^¬ NEN position and an open position, the first tong half 14 rela tively ^¬. In the closed position, the two tong halves 14, 16 are so far approximated that they are on under ^¬ different sides with, for example, two sheets to be welded 15a, 15b or for example a pressure force ^¬ measuring device 17 in pressing contact. The production forceps 11, as the welding ^¬ pliers 12 shown in Fig. 1 may be arranged to be stationary or can be moved shown by an industrial robot 1, as exemplified in the following FIG. 2. FIG. 2 shows an exemplary industrial robot 1 which has a robot arm 2. The robot arm 2 comprises, in the case of the present embodiment a plurality of nacheinan ^¬ disposed and connected by means of joints LI to L6 members Gl to G7. If a link is particular to a frame 3 and a relative to the frame 3 about a vertically extending axis AI rotatably mounted carousel 4. Other members of the robot arm 2, in the case of vorlie ^¬ constricting embodiment of a rocker 5, an arm top 6 and a preferably multi-axis robot hand 7 with a fastening device designed as a flange 8 for fastening a tool, such as the production tongs 11. Die

Rocker 5 is pivotally mounted on the carousel 4 about a preferably horizontal axis of rotation A2 at the lower end, ie at the joint L2 of the rocker 5, which may also be referred to as swingarm head. At the upper end of the rocker 5, the rocker 5 is in turn pivotally mounted on the first joint L3 about a likewise preferably horizontal axis A3 of the arm extension 6. This end carries the robot hand 7 with its preferably three axes of rotation A4, A5, A6. The joints LI to L6 are each connected by an electromotive Driven Ml to M6 via a robot controller 10 Programmgesteu ^¬ ert drivable.

On the flange 8 of the robot arm 2, a manufacturing tool 11, such as the welding gun 12 shown in FIG. 1, be ^¬ strengthened and calibrated according to the method described below with reference to FIG. 3 and / or operated.

The diagram schematically shown in Fig. 3 shows a plurality of results from multiple penetrations of invention ^shown SEN method for calibrating the tongs pressing force of the bumper ^¬ cally drivable manufacturing pliers 11 in reverse, which for generating a pair of pliers pressing force the two mutually adjustably mounted, each having a forceps tip 13a, 13b comprehensive pliers halves 14, 16 has. The manufacturing ^¬ pliers 11 also instructs the drive 20, which is formed, at least one of the clamp halves 14, 16 to move to drive automatically between the two tongs tips 13a, 13b establish a Zangenpress- force, the drive 20 is ert positionsgesteu- leaves such that a desired forceps pressing force is controlled by automatically setting a target drive position of the drive 20 associated with the desired forceps force by a closing movement of the forceps halves 14, 16.

The multiple executing the procedure is carried out a ^¬ hand from different start-target tongs pressing force values of 2000 N (Newton), 2500 N, 3000 N, 3500 N and 4000 N, in particular in the example illustrated in steps of equal Stufenab- article of 500 N.

The multiple executing the procedure is performed with various alterations ^¬ hand, by virtue of reduced target driving position values of the drive 20, in particular with different force reduced target drive position values of the drive 20 in steps of equal step spacing of 250 N. Thus, in a first cycle, a start-to-set forceps force force value of 2000 N is assumed, and from there is reduced to four different target target forceps forces. At the first target caliper force, the force is reduced by 250 N, ie to 1750 N. The second target setpoint gun force is reduced by 500 N, ie to 1500 N. At the third target setpoint gun force is reduced by 750 N, ie to 1250 N. In the fourth target-set gun force is reduced by 1000 N, ie to 1000 N.

However, as illustrated, the desired actual target gun forces of 1750 N, 1500 N, 1250 N and 1000 N do not set, but in fact about 1700 N, 1490 N, 1200 N and 900 N.

In the remaining cycles, a start-to-set caliper force value of 2500 N, 3000 N, 3500 N, and 4000 N is assumed, and from there to four different target-target nip press forces, i. reduced by 250 N, 500 N, 750 N and 1000 N respectively.

Each time closing of the open pliers halves 14, 16 takes place by position-controlled movement of the drive 20 in a start-drive position of the drive 20, in which the plier tips 13a, 13b of the two pliers halves 14, 16 one of the start-drive position associated start-target forceps pressing force apply to the pressure force measuring device 17.

Thereafter, each reversing of the closed pliers halves 14, 16 takes place by position-controlled movement of the drive 20 in a relation to the start-target forceps force force-reduced target drive position of the drive 20, in which the pliers tips 13 a, 13 b of the two pliers halves 14, 16 one of the target drive position of the drive 20 associated, compared to the start-target forceps press force force-reduced target-target-forceps pressing force is to apply to the pressure force measuring device 17.

Then, a target actual nipper force in the kraftredu ^¬ ornamented target drive position of the drive 20 through the

Compressive force measuring device 17 measured. In addition, a saving of the target-actual forceps pressing force associated with the force-reduced target drive position of the drive 20 takes place.

In FIG. 4, the obtained nip force force deviations are the difference between the target set nipper force and the measured target nip force in the form of drive position deviation values (0-2-4-6-8- 10-12- 14) applied. This Antriebspositions- deviation values are obtained by a process, aufwei ^¬ send the step of determining in each case one associated with the respective pincers pressing-force deviation value Antriebsposi- tions deviation value, in particular based on a li ^¬-linear relationship of the various drive positions of the drive 20 and the associated setpoint Pliers press forces when closing the pliers halves 14, 16. The bases of drive position deviation values shown in FIG. 4 are applied interpolated in a family of straight lines S1, S2, S3 and S4 in a generalized manner according to the method according to the invention, comprising the step of linear Interpolating between a plurality of interpolation points of the driving-position deviation values resulting from the plurality of different start-to-target force pressing force values. The interpolation points and / or interpolated intermediate points or the straight lines can be in the form of a table or a function, from which a required, for reversing actuation of the production tongs, the desired one Start-Soll-Zangenpresskraftwert assigned Antriebssports-subtungswert is to be stored.

In this case, the gradients ZI, Z2, Z3 and Z4 of the interpolated lines S1, S2, S3 and S4 can be determined and likewise stored for later retrieval. For example, as shown in FIG. 4, the straight line Sl has a pitch of y = 0.0021x. The straight line S2 has a slope of y = 0.0029x. The straight line S3 has a slope of y = 0.0040x. The straight line S4 has a pitch of y = 0.0047x.

These slopes ZI, Z2, Z3 and Z4 are plotted as a base in a diagram of FIG. By way of these interpolation points of the gradients ZI, Z2, Z3 and Z4, an approximate straight line GG can again be laid, which thus provides a function of the slope of the game factor as a function of the force difference.

In summary it can be said that the tongs pressing force deviation, that is the error of the actually set target actual tongs pressing force to the desired target setpoint tongs pressing force is greater, the higher the output ^¬ pressing force, that is, a start actual tongs pressing force is from which the forceps force is reduced. The error manifests itself in relation to the desired or assumed one

Nominal forceps force to low target actual forceps force. It can also be said that the higher the reduction of the initial pressing force, ie, the jump in magnitude from the start actual, the greater the pincer force deviation, ie, the error of the actual set target pincer pressing force to the desired target pincer pressing force Pliers press force is in the force-reduced target target forceps press force. In other words, the higher gear, the pressing force from ^¬ and / or the greater the Kraftreduktionsbe- support is, the more effected by the tongs pressing force stored potential energy in the manufacturing tongs 11 that the pliers halves are opened more than desired and set in consequence of a too low reduced target-actual forceps press force.

Claims

claims

1. A method for calibrating the tongs pressing force of an automatically controllable manufacturing tongs (11) in the reversibility sierbetrieb used to generate a pair of pliers pressing force two mutually adjustably mounted, in each case a pair of pliers tip (13a, 13b) Comprehensive pincers (14, 16) has ^¬, and a drive (20) which is ausgebil ^¬ det, at least one of the pliers halves (14, 16) to move to build a forceps force between the two pliers tips (13a, 13b), wherein the drive (20) can be automatically driven position controlled in such a way that a desired plier pressing force is achieved by automatically setting a desired drive position of the drive (20) associated with the desired plier pressing force by means of a

Closing movement of the pliers halves (14, 16) is driven, comprising the steps:

Positioning a pressure force measuring device (17) between the two open tong halves (14, 16) as a force measurement standard for measuring the force of the forceps force between the two tong tips (13a, 13b);

Closing the open pliers halves (14, 16) by position-controlled movement of the drive (20) into a ^¬ ne start drive position of the drive (20) in which the forceps tips (13a, 13b) of the two chuck halves (14 16) one of the start Drive position associated start-desired forceps press force on the pressure force ^¬ measuring device (17) apply;

Reversing the closed pliers halves (14, 16) by position-controlled movement of the drive (20) in a relation to the start-target forceps force force-reduced target drive position of the drive

(20), in which the plier tips (13a, 13b) of the two pliers halves (14, 16) one of the target drive position of the drive (20) associated with respect to the start-Soll-Zangenpresskraft force-reduced target-Soll- Zangenpresskraft on the pressure force measuring device

(17) should apply;

Measuring a target-actual forceps pressing force in the force ^¬ reduced target drive position of the drive (20) by the pressure force measuring device (17);

Saving the target-actual gun force associated with the force-reduced target drive position of the drive (20).

The method of claim 1, comprising the step of

Determining a caliper force deviation value from the difference between the target caliper force and the measured target force force.

The method of claim 1 or 2, comprising the step of multiple execution of the procedure according to ^¬ claim 1. or 2, with various start-target tongs pressing force values, in particular with different starting target tongs pressing force values in steps of equal Stu fenabstands, and storing each of the jewei ^¬ then start target pliers pressing force value assigned Zan ^¬ genpresskraft deviation value per start target pliers pressing force value. The method of claim 1 or 2, comprising the step of multiple execution of the procedure according to ^¬ entitlement 1 or 2 with various power-reduced target driving position values of the drive (20) in which the forceps tips (13a, 13b) (the two pincers 14, 16 ) one of the respective target drive position of the drive (20) associated, opposite the start-target tongs pressing force by virtue of reduced target setpoint tongs pressing force to the pressing force measuring device (17) is to apply, especially with different kraftre ^¬ duced target drive position values of the drive (20) in steps of equal step spacing, and storing each ^¬ weils of the respective target drive position value to ^¬ parent tongs pressing-force deviation value depending on target drive position value.

The method of claim 4, comprising the step of determining in each case one associated with the respective Zangenpresskraft- deviation value Antriebspositions- deviation value, in particular on the basis of a line ^¬ arene relationship of the various drive positions of the drive (20) and the associated target tongs pressing forces during the closing of the pliers halves (14 , 16).

Method according to one of Claims 1 to 5, comprising the step of linearly interpolating between a plurality of interpolation points of the drive-position deviation values resulting from the plurality of different start-to-set forceps force values and / or storing linear interpolated intermediate values, in particular in the form of a table or a function, from which a re-required activation of the production tongs (11) a benö ^¬ tigter, the desired start-desired Zangenpresskraftwert assigned drive position deviation value to entneh ^¬ men is.

Method for the automatic control of a production tongs (11) in reversing operation, which has two Zan ^¬ genhälften (14, 16) mounted mutually adjustable, each one a pair of pliers tip (13a, 13b) comprehensive for generating a forceps, and having a drive (20), which is formed, at least one of Zan ^¬ gene halves (14, 16) to move to between the two tongs tips (13a, 13b) establish a pliers pressing force, wherein the drive (20) can be positionally controlled to drive automatic ^¬ table, such that a pliers target pressing force associated by automatically adjusting one of the target pressing force pliers target driving position of the drive (20) by a closing movement of the clamp halves (14, 16) is controlled, comprising the Schrit ^¬ te:

Specifying a target-target-forceps pressing force, which is gerin ^¬ ger, as a momentarily exerted by the manufacturing tongs (11) actual forceps pressing force;

Determining one of the target set point tongs pressing force applied ^¬ associated target driving position of the drive (20) taking into account Antriebspositions- deviation values which are obtained by a process according to claims 1 to 6, in particular of intermediate values from a table or according to a function that are generated based on drive position deviation values of a method according to claim 1 to 6; Reversing the closed pliers halves (14, by position-controlled movement of the drive in the specific target drive position.

A method according to claim 7, wherein for determining the target drive position of the drive (20), a relationship known between the desired plier press force and the associated desired drive position of the drive (20) is used to actuate a closing movement of the plier halves (14, 16) and from this connection, a target target drive position associated with the target set gun force is determined and corrected by the determined drive position deviation value, and based on which a reversing movement of the tong halves (14, 16) is controlled to reach the target position. Set the nominal force of the forceps.

System of welding tongs, clinching tongs, one

Crimping tool, and / or a GreifTerkzeugs and STEU ^¬ ervorrichtung for automatically moving the welding gun, the clinching pliers, the crimping tool, and / or GreifWerk ^¬ zeugs, which control device (10) is arranged to perform a method according to one of claims 1 to 8 ,

System according to claim 9, wherein the control device (10) has a memory in which drive position deviation values, in particular intermediate values according to a table or according to a function, which are obtained by a method according to claims 1 to 6 are stored and these drive position values are stored. deviation values, in particular ^¬ sondere intermediate values from the memory for performing a method according to claim 7 or 8 are available.