JP2009101377A - Press machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To allow a slide to be surely forcedly stopped at a set stop position when detecting a mistake. <P>SOLUTION: The press machine includes: a stop position setting means; a mistake detection position setting means; a deceleration start position setting means; a deceleration control means; a forced stop control means; and an acceleration control means. When a slide during lowering reaches a deceleration start position P3 based on motion information, deceleration control can be started, when a mistake is detected at a mistake detection position P2, the slide can be forcedly stopped at a stop position P1 by forced stop control, and when a mistake is not detected, the speed decelerated by acceleration control can be returned to the original deceleration speed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a press machine that is capable of controlling the rotational drive of a motor based on motion information and capable of press forming within a set region while converting the rotational motion of the motor into a lifting and lowering motion of a slide via a slide drive mechanism.

  In a press machine using a servo motor, various slide motions can be easily set (selected) and changed (for example, Patent Document 1). Since the slide can be temporarily stopped, lowered at a low speed, and reversed up and down, the adaptability to the press molding mode can be expanded and a high-quality product can be produced.

  In such a press machine, the motor rotation control unit controls the rotation of the motor in accordance with motion information (motion command signal) set (or selected) in advance. The slide drive mechanism unit drives the slide by using the motor rotation power generated by the motor rotation as an input. As the slide drive mechanism, a crank mechanism, a link mechanism or a screw mechanism is known. In any slide drive mechanism, motion information is defined (created) as a slide position for each process (time, angle, etc.). )

  FIG. 4 shows the case of the crank mechanism, and the slide is lowered (raised) according to the motion (the locus Rprs... Shown by the dotted line in FIG. 3).

  In actual press operation, the relationship with the material conveyance operation is detected, and whether or not interference between the material and the mold occurs is predicted and determined. For example, when the position of the descending slide reaches a setting error detection position P2 shown in FIG. 3A, it is detected whether or not the material has been normally conveyed. If the conveyance is incomplete or incomplete, if this is left unattended, there is a strong possibility that the mold will be damaged when the slide is at the lowest position.

  Therefore, when a mistake is detected at the setting mistake detection position P2, it is desirable to forcibly descend according to the locus Rstp shown by the solid line in FIG. That is, the slide is forcibly stopped at the position P1 before the lowest position (bottom dead center) P0 to prevent breakage. In the case of a press machine that detects whether or not the material is a coil material and the pilot pin is fitted in the pilot hole, it is forcibly stopped in the same manner.

  By the way, if the miss detection position is set to a position higher (upstream) than the position P2, the slide forced stop operation time at the time of miss detection can be increased, but the material transport operation time is shortened. On the other hand, if the miss detection position is set to a position (downstream side) that is much lower than the position P2, it is advantageous in terms of the conveyance operation because the material conveyance operation time can be afforded, but the slide is forcibly stopped. The operating time allowed for this is shortened.

  Thus, in practice, the misdetection position is carefully examined and set carefully in the adjustment work by the trial operation while comparing and considering the material conveyance situation and the mold protection situation. Rather than setting the detection position P2 in terms of software, the setting using the rotary cam switch is more troublesome and requires more adjustment time. In any case, it is understood that the error detection position once set (determined) should not be easily changed.

  However, when the production speed (slide speed) changes at a high speed or when the setting is changed to the high speed side, the misdetection position set at the turning angle becomes inadequate. That is, in a system in which a mistake is detected at a fixed miss detection position and the stop is performed according to the fixed stop motion (trajectory Rstp) shown in FIG. A situation occurs in which the vehicle cannot stop at the position P1.

Regarding this speed change point, a work interference prevention device that detects the production speed, that is, the number of strokes per hour (spm) and corrects the interference detection angle using data (slip angle, etc.) corresponding to the number of strokes is proposed. (Patent Document 2). That is, when the material feeding is not completed at the corrected interference detection angle (miss detection position), the determination unit determines that interference occurs. Then, the control means starts the press stop control.
JP 2003-205395 A Japanese Patent Laid-Open No. 9-295197

  However, this proposed (Patent Document 2) apparatus is limited to an apparatus (for example, a horizontal conveying system for coil materials) in which the conveyance speed is easy to follow but the slide speed is difficult to follow in response to a request for high speed. This is because even if the interference detection angle is set to a smaller value (corrected) depending on the detected spm, it does not place an unreasonable burden (disadvantage) on the conveying device side. Although the press stop control is started from the corrected interference detection time point, there is no technical basis for reliably stopping at a safe position because the press cannot perform rapid deceleration.

  In other words, it is a press machine that can freely set the production speed and there is a limit to increasing the conveyance speed, or it is practically impossible to change the conveyance speed to one higher speed because of mechanical inertia and the like. As is possible, it cannot be introduced in a press machine that has a close relationship with the conveying device.

  An object of the present invention is to provide a press machine that can surely stop a slide at a set stop position when a mistake is detected without adversely affecting the conveying device side.

  The present invention allows the setting change of the error detection position and ensures that the slide is in the safe position only by the countermeasure on the press side, without causing the disadvantage that the setting change is difficult or the high-speed tracking cannot be performed on the workpiece transfer device side. It is formed so that it can be forcibly stopped.

  In other words, the press machine according to the first aspect of the present invention can control the rotation of the motor based on the motion information, and can perform press molding in the set region while converting the rotational movement of the motor into the up-and-down movement of the slide via the slide drive mechanism. In the press machine formed in, deceleration control can be set when the deceleration start position above the setting error detection position can be set and the position of the slide that is descending at the speed based on the motion information reaches the set deceleration start position. If a mistake is detected at the setting error detection position, the slide can be forcibly stopped at the setting stop position by forced stop control.If no error is detected, the speed reduced by acceleration control is set. It is formed to be able to return to the original descending speed based on the motion information.

  The press machine according to the invention of claim 2 is formed so that the motor can be rotationally driven based on the motion information and can be press-molded within the set region while converting the rotational motion of the motor into the up-and-down motion of the slide via the slide drive mechanism. In the pressed machine, a stop position setting means for setting a forced stop position determined to surely stop the slide reliably, a miss detection position setting means for setting a position to detect a mistake, and a position above the set mistake detection position A deceleration start position setting means for setting a deceleration start position on the side, a deceleration control means for starting deceleration control when the position of the slide that is descending at a speed based on the motion information reaches the set deceleration start position, and a setting error Forced stop control that starts forced stop control and forcibly stops the slide at the set stop position when a mistake is detected at the detection position And stage, a structure in which a speed increasing control means for the speed reduced by accelerated controlled back to lowering speed of the original based on the motion information, the if it is not a miss detected in setting error detection position.

  According to a third aspect of the present invention, the deceleration rate calculation means calculates the deceleration rate using the setting error detection position and the set stop position, and the forced stop control means executes the forced stop control at the calculated deceleration rate. it can. According to a fourth aspect of the present invention, the deceleration control means performs deceleration control with the calculated deceleration rate.

  According to the first aspect of the present invention, it is possible to provide a press machine capable of reliably forcibly stopping the slide at the set stop position when a mistake is detected without causing any disadvantage (reasonableness) to the conveying device side. In addition, even if the error detection position is changed, reliable error detection can be performed, and deceleration control can be performed prior to the time of error detection, so that it is safe and easy to handle.

  According to the second aspect of the present invention, the same effect as in the case of the first aspect of the invention can be obtained. Further, since it is only necessary to operate three input means, the handling is easier and the adaptability is wider.

  According to the invention of claim 3, in addition to being able to achieve the same effect as that of the invention of claim 2, the slide forced stop control is performed at the calculated deceleration rate, so that the stable forced stop control and the shockless state are achieved. Press to stop.

  Furthermore, according to the invention of claim 4, in addition to being able to achieve the same effect as in the case of the invention of claim 3, it is decelerated from the preceding position with the same calculated deceleration rate as in the case of forced stop control. The slide can be forcibly stopped more smoothly and reliably.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.

  1 to 3, the press machine 1 includes a stop position setting means (25), an error detection position setting means (25), a deceleration start position setting means (25), and a deceleration control means (21, 22, 23). ), Forced stop control means (21, 22, 23) and acceleration control means (21, 22, 23) are provided, and the current position P of the slide 6 that is descending at a speed (motion... Locus Rprs) based on the motion information. When the motor reaches the set deceleration start position P3, deceleration control can be started. If a mistake is detected at the setting error detection position P2, the slide 6 can be forcibly stopped at the setting stop position P1 by the forced stop control, and a mistake is detected. If not, the speed reduced by the speed increasing control can be returned to the original descending speed based on the motion information.

  Confirmingly, the press machine 1 can control the rotational drive of the motor based on the motion information, and converts the rotational motion of the motor 7 into the up-and-down motion of the slide 6 via the slide drive mechanism (crank mechanism 2). It is formed so that it can be press-molded.

  In FIG. 1, the slide drive mechanism is composed of a crank mechanism 2 including a crankshaft 3 (crank portion 4). The crankshaft 3 can be reversibly rotated (forward rotation, reverse rotation) by rotation control of an AC (alternating current) servomotor 7 that is rotatably supported by a bearing and directly connected thereto. The servo motor 7 may be a DC (direct current) servo motor or a reactance motor.

  In addition, you may connect the crankshaft 3 and the motor 7 indirectly via a gear (reduction gear). A higher pressurizing force can be obtained through a gear (reduction gear). Further, the slide drive mechanism can be implemented even when formed from a link mechanism or a ball screw mechanism.

  The slide 6 is mounted on the frame body so as to be slidable in the vertical direction, and is engaged with the balance device. If the crankshaft 3 is rotationally driven, the slide 6 can be driven up and down via the connecting rod 5. The mold is composed of an upper mold on the slide 6 side and a lower mold on the bolster (not shown) side.

  The encoder 8 connected to the AC servomotor 7 has in principle a large number of optical slits and optical detectors, and outputs the rotation angle (crank angle) θ of the motor 7 (crankshaft 3). In this embodiment, a signal converter (not shown) that converts the rotation angle θ (pulse signal) into a vertical position (pulse signal) of the slide 6 and outputs it is included.

  A press control panel 20 shown in FIG. 1 includes a CPU 21, a non-volatile memory (ROM, HDD, etc.) 22, a memory (flash RAM, etc.) 23 that can store and retain data even when the power is turned off, and a touch panel 24 (operation unit 25 and display unit). 26) and interfaces 27 and 28, and by generating and outputting the motion command signal Smtn to the motor rotation control unit 30 by the actual press operation program stored in the memory 22, the rotation of the servo motor 7 is controlled and the slide 6 is moved up and down. be able to. In FIG. 1, items relating to the workpiece transfer device and the like are not shown.

  The motion trajectory (motion information) of the slide 6 is data in which the elapsed time t (or angle θ) is associated with the slide position P, and can be set using the operation unit 25. The set motion information is stored in the motion information area 22mtn in the nonvolatile memory 22 so that it can be selected and used later. The motion information selected prior to the actual press operation is developed in the memory 23 that can store and hold it.

  The miss detector 9 is attached near the column of the press main body and detects the material conveyed by a material conveying device (not shown). In this embodiment, if the material can be detected before the slide 6 reaches the error detection position P2 (ST16 in FIG. 2), the conveyance is normal.

  In the actual press operation, when desired motion information is selected using the operation unit 25, the motion command unit (21, 22, 23) having a position pulse delivery system structure stores the stored actual press operation program (motion command signal generation). 1 is output to the motor rotation control unit 30 in accordance with the output control program. For example, if the motor rotation speed is 120 RPM, the number of pulses output from the encoder 8 per rotation (360 degrees) is 1 million pulses, and the payout cycle time is 5 mS, it is output every cycle (5 mS). The number of pulses is 10,000 pulses [= (1000000 × 120) / (60 × 0.005)].

  As a measure for preventing a rapid torque change, it is preferable to provide an acceleration section (the number of output pulses gradually increases) immediately after startup and a deceleration section (the number of output pulses gradually decrease) immediately before stopping.

  In the motor rotation control unit 30 receiving the motion command signal Smtn, the position comparator 31 compares the motion command signal Smtn, which is a target value, with the actual slide position signal (feedback signal f) detected by the encoder 8. A position deviation signal is generated and output.

  The position / speed control unit (position control unit) 32 accumulates the input position deviation signal, multiplies it by a position loop gain, and generates and outputs a speed signal. A speed comparator (not shown) compares the speed signal with the speed signal from the speed detector (encoder 8) (in this case, the speed component of the signal f) and generates and outputs a speed deviation signal. The speed control unit multiplies the input speed deviation signal by a speed loop gain and generates and outputs a current command signal to the current control unit (amplifier 33). This current command signal is substantially a torque signal.

  The amplifier 33 generates each phase target current signal and generates and outputs a current deviation signal. Subsequently, a PWM signal is generated from the current deviation signal of each phase by PWM control and pulse width modulation. Finally, switching (ON / OFF) control is performed by each PWM signal, and each phase motor drive current U, V, W can be output. Thus, the servomotor 7 can be rotationally driven.

  The motor rotation control unit 30 receives not only the motion command signal Smtn input from the motion command unit (21, 22, 23) but also the deceleration control command signal Srd, the acceleration control command signal Sic, and the forced stop control command signal Sstp. Each control operation can be executed even when switching is input.

  The stop position setting means is a means for setting a forced stop position (P1 in FIG. 3) which is formed from the keys of the operation unit 25 and the like and is determined to surely stop the slide 6 forcibly. The setting stop position P1 is stored and held in the area P1 of the memory 23. Since the stop position P1 is a position for preventing damage to the mold, it is often set immediately before the lowest position (bottom dead center) P0.

  Similarly, the miss detection position setting means is a means that is formed from a key or the like of the operation unit 25 and sets a position (P2 in FIG. 3) for detecting a mistake. The setting error detection position P2 is stored and held in the area P2 of the memory 23.

  In general, the mistake detection position P2 is frequently set because it is carefully determined from the viewpoint of the conveyance speed followability on the conveyance device side and the productivity on the press machine 1 side to ensure the forced sliding stop in an emergency. Is not to be done.

  However, according to the present invention (embodiment), the deceleration rate for forced stop control can be calculated from the relationship between the two positions (P1, P2) instead of being uniform (constant) from the characteristics of the servo press (1). The forced stop control is performed at the deceleration rate that is formed and calculated. In other words, a deceleration rate that can reliably stop the slide is adopted. Thus, the setting error detection position P2 can also be set relatively freely as compared with the conventional example.

  Furthermore, in this embodiment, in order to enable forced stop control with a further marginal deceleration rate, the deceleration rate can be set to the other two positions (P1, P1, in preparation for higher production speed and larger equipment). P3) It can be calculated from the relationship. Therefore, as shown in FIG. 3B, the deceleration rate (trajectory Rrd) during the deceleration control and the deceleration rate (trajectory Rstp) during the forced stop control can be made the same. In this way, it is not necessary to switch the deceleration rate at the miss detection position P2 when a miss is detected. Smooth control transfer is possible.

  The deceleration start position setting means is a means that is formed from the keys of the operation unit 25 and the like, and sets a deceleration start position (P3 in FIG. 3) above the setting error detection position P2. The set deceleration start position P3 is stored and held in the area P3 of the memory 23. However, the deceleration start position P3 can be set as a fixed value depending on the production speed.

  The deceleration start position setting means may be formed such that a position that is preceded by a predetermined amount above the error detection position P2 set by the error detection position setting means can be automatically set. In this way, two position setting means can be provided.

  The deceleration control means includes a memory 22 (area Rrd) that stores a deceleration control program, a CPU 21 that executes the program, and a memory 23. When it is determined by the first determination means (22, 21, 23) that the position of the slide 6 that is descending at the speed based on the motion information has reached the set deceleration start position P3 shown in FIG. 2 (YES in ST14), deceleration control is started from the current speed V2 to V1 shown in FIG. 3B (ST15). The speed trajectory during deceleration is a trajectory Rrd in FIG.

  The reason why deceleration control is preceded before detection of a mistake is to provide a margin in the range of deceleration rates that can be taken during forced stop control. This is because the deceleration rate is calculated from the difference between the speed V1 at the position P2 and the speed V0 at the position P0. In this sense, if the deceleration rate is calculated in relation to V2 at the position P3 as described above, a more stable (shockless) forced stop control can be performed.

  The forced stop control means (22, 21, 23... Is the same as the case of the deceleration control means. The same applies hereinafter) is detected by the second determination means (22, 21, 23) as a mistake at the setting error detection position P2. If it is determined (YES in ST16, YES in ST17), the forced stop control is started to forcibly stop the slide 6 at the set stop position P1. The speed trajectory during the forced stop control is a trajectory Rstp in FIG. The forced stop control program is stored in the memory 22 (area Rstp).

  The speed increasing control means (22, 21, 23) for returning returns the reduced speed to the original descent based on the motion information when no error is detected at the setting error detection position (YES at ST16) (NO at ST17). Speed increase control is performed to reach speed V2 (YES in ST20 and ST21). The return acceleration control program is stored in the memory 22 (area Rin). The acceleration locus is Ric shown in FIG.

  Since there is this return acceleration control process, even if the preceding deceleration control process is provided, the productivity is not adversely affected. It is understood that the flexibility of selecting and changing the press speed is effectively utilized. In this sense, it is preferable to increase the speed increase as much as possible.

  The deceleration rate calculation means (22, 21, 23) slides using the speed V1 (or V2) at the setting error detection position P2 (or P3) and the speed (V0 = 0) at the setting stop position P1. 6 is calculated (ST13) as a deceleration rate necessary for surely stopping 6 at the set stop position P1. The calculation control program is stored in the memory 22 (area Cal).

  The forced stop control means (22, 21, 23) performs forced stop control at the calculated deceleration rate. The velocity trajectory at this time is the trajectory Rstp shown in FIG. In this embodiment, the deceleration control by the deceleration control means (22, 21, 23) is also performed at the calculated deceleration rate.

  In the embodiment having such a configuration, when desired motion information is selected using the operation unit 25 in actual press operation, the motion command unit (21, 22, 23) is shown in FIG. 1 according to the motion command signal generation output control program. The motion command signal Smtn is output to the motor rotation control unit 30. As a result, the slide 6 descends with the motion (trajectory Rprs) shown in FIG.

  Then, the deceleration rate calculation means (22, 21, 23) designates two (P3 · P1 or P2 · P1 in advance) of the set stop position P1, the setting error detection position P2 and the set deceleration start position P3 read from the memory 23. ) To calculate the deceleration rate (ST10 to ST13 in the figure).

  When the slide 6 reaches the set deceleration start position P3 (YES in ST14), the deceleration control means (22, 21, 23) precedes and executes deceleration control (ST15). The vehicle decelerates along the locus Rrd in FIG.

  When the slide 6 reaches the setting error detection position P2 (YES in ST16), the error detection control means (22, 21, 23) monitors the detection signal of the error detector 9 and detects an error (YES in ST17).

  Then, the forced stop control means (22, 21, 23) starts the forced stop control at the calculated deceleration rate. The vehicle decelerates along a locus Rstp (= Rrd) in FIG. When the set stop position P1 is reached (YES in ST19), the forced stop control is terminated, and the slide 6 is locked at that position P1. Mold protection is possible.

  If no error is detected (NO in ST17), the speed increasing control means (22, 21, 23) for returning performs speed increasing control (ST20). The speed is increased by the locus Ric. When the original descent speed is reached (YES in ST21), the operation returns to the operation based on the selected motion information.

  Therefore, according to this embodiment, stop position setting means (25), error detection position setting means (25), deceleration start position setting means (25), deceleration control means (21, 22, 23), and forced stop When the control means (21, 22, 23) and the acceleration control means (21, 22, 23) are provided, and the slide 6 descending at the speed (trajectory Rprs) based on the motion information reaches the set deceleration start position P3 If a mistake is detected at the setting error detection position P2, it is forcibly stopped at the setting stop position P1 by the forced stop control. If no error is detected, the speed is lowered to the original lowering speed by the acceleration control. Since it is formed so as to be able to return, the slide can be surely forcibly stopped at the set stop position when a mistake is detected without causing any disadvantage (reasonableness) to the conveying device side. In addition, even if the error detection position is changed, reliable error detection can be performed, and deceleration control can be performed prior to the time of error detection, so that it is safe and easy to handle.

  Moreover, since it is only necessary to set the three positions P3, P2, and P1 by operating the three input means (25), the handling is easier and the adaptability is wider.

  Since the deceleration rate calculation means calculates the deceleration rate using the setting error detection position P2 and the set stop position P1, and the forced stop control means executes the forced stop control at the calculated deceleration rate, stable forced stop control and reliable Can stop the press.

  Further, the deceleration rate calculation means is caused to calculate the deceleration rate by using the set deceleration start position P3 and the set stop position P1 by switching, and the deceleration control means and the forced stop control means respectively control with the calculated deceleration rate. Since it is formed, the press can be stopped in a shockless state under more stable control. In addition, the adaptability is wide.

  Further, the deceleration control means performs deceleration control with the calculated deceleration rate. That is, the slide is decelerated from the preceding position at the same calculated deceleration rate as in the case of forced stop control, so that the slide can be forcibly stopped more smoothly and reliably.

  INDUSTRIAL APPLICABILITY The present invention can be used in a press machine that needs to ensure mold protection without causing a disadvantage on the conveying device side.

It is a block diagram for demonstrating embodiment of this invention. Similarly, it is a flowchart for explaining the operation. Similarly, it is a timing chart for explaining the operation. It is a figure for demonstrating a prior art example and its problem.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Press machine 2 Crank mechanism 6 Slide 7 Servo motor 9 Miss detector 20 Press control panel 21 CPU (Deceleration control means, forced stop control means, speed increase control means)
22 Non-volatile memory (deceleration control means, forced stop control means, speed increase control means)
23 Memory that can be stored (deceleration control means, forced stop control means, speed increase control means)
25 Operation part (stop position setting means, error detection position setting means, deceleration start position setting means)
26 Display unit 30 Motor rotation control unit

Claims (4)

In a press machine that is capable of controlling the rotational drive of a motor based on motion information and capable of press molding within a set region while converting the rotational motion of the motor to a lifting and lowering motion of the slide via a slide drive mechanism.
It is possible to set a deceleration start position above the setting error detection position and form a deceleration control so that the deceleration control can be started when the position of the descending slide reaches the set deceleration start position at a speed based on the motion information.
If an error is detected at the setting error detection position, the slide can be forcibly stopped at the setting stop position by the forced stop control.If no error is detected, the speed reduced by the acceleration control is calculated based on the original motion information. A press machine that can be returned to its descending speed. In a press machine that is capable of controlling the rotational drive of a motor based on motion information and capable of press molding within a set region while converting the rotational motion of the motor to a lifting and lowering motion of the slide via a slide drive mechanism.
Stop position setting means for setting a stop position determined to surely stop the slide forcibly,
A miss detection position setting means for setting a position to detect a mistake;
Deceleration start position setting means for setting a deceleration start position above the setting error detection position;
Deceleration control means for starting deceleration control when the position of the slide that is descending at a speed based on the motion information reaches a set deceleration start position;
Forced stop control means for starting forced stop control and forcibly stopping the slide at the set stop position when a mistake is detected at the setting error detection position;
Speed increasing control means for returning to the original descending speed based on the motion information when the speed is controlled to increase when no error is detected at the setting error detecting position;
Press machine.   A deceleration rate calculation means is provided to calculate the deceleration rate necessary to reliably stop the slide at the set stop position using the setting error detection position and the set stop position, and the deceleration rate calculated by the forced stop control means is provided. The press machine according to claim 2, wherein the forced stop control is performed by the controller.   The press machine according to claim 3, wherein the deceleration control means performs deceleration control at the calculated deceleration rate.