JP2010125456A - Double-acting press machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a double-acting press machine where the driving mechanism of an outer slide can be simplified, wrinkle pressing time can be adjusted in accordance with the depth of drawing, and wrinkle pressing force can be controlled without providing the inside of the outer slide with a wrinkle pressing force regulation mechanism. <P>SOLUTION: The double-acting press machine is provided with: an outer slide 7 in which a blank holder performing the wrinkle pressing of a workpiece is installed at the lower face, and which is driven to be elevated; and an inner slide in which a punch 5 is installed at the lower face, and which is driven to be elevated at the inside of the outer slide 7. The double-acting press machine is also provided with: an outer slide driving mechanism 30 having servomotors 31a, 31b, 31c, 31d and driving the outer slide 7 to be elevated with the servomotors as driving sources; and an outer slide controller 50 controlling the servomotors in such a manner that the outer slide 7 is elevated in accordance with a prescribed operational pattern. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a double-action press machine provided with an inner slide and an outer slide.

  2. Description of the Related Art Conventionally, in a press machine for drawing a workpiece, an outer slide in which a blank holder for wrinkle pressing is installed on the lower surface and driven up and down, and a punch is installed in the lower surface and driven up and down inside the outer slide One with an inner slide is known. This type of press machine is called a “double-acting press machine”. In press working, the outer slide descends prior to the inner slide, a blank holder attached to the outer slide presses the peripheral edge of the workpiece, and then the workpiece is drawn or the like by lowering the inner slide.

As a mechanism for driving an outer slide in a double-action press machine, for example, there is a link mechanism as shown in Patent Document 1.
Further, in a double-acting press machine, in order to control the wrinkle pressing force, an air chamber or a hydraulic chamber is provided at a point of the outer slide, and a configuration for controlling the air pressure or hydraulic pressure therein is used. As such a wrinkle pressing force control mechanism, for example, there is a configuration as shown in Patent Document 2.

Japanese Utility Model Publication No. 63-40320 Japanese Patent Publication No. 7-63879

  In order to suppress wrinkles, the outer slide needs to stop for a certain period of time at the bottom dead center. On the other hand, the outer slide descends from the top dead center to the bottom dead center at a high speed to secure time for the panel (workpiece) that is the object to be drawn into and out of the die, and from the bottom dead center to the top dead center. Rise to. Since the flywheel continues to rotate at a constant speed, in order to realize such an operation of the outer slide, a complicated link mechanism as shown in Patent Document 1 is required, which is difficult to manufacture, adjust and maintain. It becomes.

  Also, when exchanging various objects by exchanging dies, punches and blank holders, lengthen the wrinkle holding time for deep objects and shorten the wrinkle holding time for shallow objects. Is inherently desirable. However, since the link mechanism cannot be changed in the conventional technique, even when a shallow object is drawn, the wrinkle holding time is the same as that when a deep object is drawn. Therefore, cycle time cannot be shortened and productivity is not improved.

  In order to control the wrinkle holding force, it is necessary in the prior art to provide a pneumatic or hydraulic chamber, piping for air or hydraulic pressure, a valve for pressure control, or the like at the point of the outer slide. In the double-acting press, the outer slide is provided so as to surround the inner slide, so the space inside the outer slide is narrowed. Therefore, it is difficult to manufacture, prepare, and maintain the device in the outer slide.

  The present invention has been made in view of the above problems, and can simplify the outer slide drive mechanism, adjust the wrinkle holding time according to the drawing depth, and adjust the wrinkle presser force adjustment mechanism in the outer slide. It is an object of the present invention to provide a double-acting press machine that can control the wrinkle presser force without providing a cover.

In order to solve the above problems, the double-action press machine of the present invention employs the following technical means.
(1) A double-acting press machine comprising an outer slide in which a blank holder for pressing a workpiece is installed on the lower surface and driven up and down, and an inner slide in which a punch is installed on the lower surface and driven up and down inside the outer slide An outer slide drive mechanism that drives the outer slide up and down using the servo motor as a drive source, and an outer slide control device that controls the servo motor so that the outer slide moves up and down according to a predetermined operation pattern And.

  According to the configuration of the present invention described above, a servo motor is employed as a driving source for driving the outer slide, and the operating speed of the servo motor (the rotational speed for a rotary motor, the moving speed of a movable part for a linear motor). ) To change the outer slide. That is, the servomotor is driven to lower and raise the outer slide, and the servomotor is stopped to suppress wrinkles. In order to coordinate the movement of the outer slide with the movement of the inner slide, the clutch brake that turns the inner slide movement directly (such as measuring the position of the inner slide with an encoder) or indirectly (transmission of power to drive the inner slide) For example, using a command signal to The outer slide control device controls the servo motor so that the outer slide moves up and down according to the operation pattern with reference to the detected movement of the inner slide. Thus, according to the present invention, since the operation of the outer slide is controlled by the control of the servo motor, a simple link mechanism such as an eccentric mechanism can be used as the lifting mechanism of the outer slide. This facilitates production, adjustment, and maintenance.

(2) In the double-action press machine according to (1), the outer slide control device stores a plurality of operation patterns having different wrinkle holding times with respect to the lifting / lowering operation of the outer slide.

  According to the above configuration, by changing the movement pattern of the outer slide according to the drawing depth, the wrinkle holding time is lengthened for a deep object, and the wrinkle holding time is set for a shallow object. Can be shortened. That is, the wrinkle holding time can be shortened according to the object to be drawn, so that the cycle time is shortened and the productivity is improved.

(3) Also, in the double-acting press machine according to (1) or (2), the outer slide drive mechanism is configured so that the outer slide drive mechanism performs wrinkle pressing of the workpiece at a position above the bottom dead center of the outer slide drive mechanism. The outer slide control device controls the servo motor so as to generate a desired wrinkle pressing force while the wrinkle pressing of the workpiece is performed.

  According to the above configuration, it is not necessary to install a pneumatic device / hydraulic device in the outer slide having a small space in order to control the wrinkle pressing force, so that manufacture, adjustment, and maintenance are facilitated. Further, the wrinkle holding force can be changed during wrinkle pressing by changing the output command value.

(4) In the double-acting press machine of (3), a plurality of the outer slide drive mechanisms are provided, and the outer slide control device individually controls a servo motor of each outer slide drive mechanism.

  According to the above configuration, the wrinkle pressing force can be adjusted according to the position by individually controlling the servo motors of the outer slide drive mechanisms, so that the molding quality can be improved.

  According to the present invention, the driving mechanism of the outer slide can be simplified, the wrinkle pressing time can be adjusted according to the drawing depth, and the wrinkle pressing force can be controlled without providing the wrinkle pressing force adjusting mechanism in the outer slide. .

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, the same code | symbol is attached | subjected to the common part in each figure, and the overlapping description is abbreviate | omitted.

[First Embodiment]
FIG. 1 is a configuration diagram of a double-action press machine according to a first embodiment of the present invention, in which (A) is a top view of an inner slide and an outer slide, and (B) is a front view of the entire double-action press machine. .

  The double-action press machine 10 includes a punch 5 as an upper die, a die 13 as a lower die, a blank holder 9 for performing wrinkle pressing of the work 1, and a blank holder 9 installed on the lower surface and driven up and down. An outer slide 7 and an inner slide 3 on which the punch 5 is installed on the lower surface and is driven up and down inside the outer slide 7. The workpiece 1 is sandwiched between the blank holder 9 and the die 13 to suppress wrinkles, Drawing is performed by pressing the work 1 with the punch 5.

  The load applied to the bolster 11 during the drawing process is supported by the bed 15 and transmitted to the crown 21 via the upright 17. In the crown 21, an inner slide drive mechanism 20 for driving the inner slide 3 up and down and an outer slide drive mechanism 30 described later for driving the outer slide 7 up and down are provided.

  The drive system of the inner slide drive mechanism 20 is not limited to a specific one. For example, as the inner slide drive mechanism 20, the flywheel is rotated by a motor, and the rotation of the flywheel is transmitted to the main shaft via a clutch / brake mechanism, and the rotational motion of the main shaft is converted into a power conversion mechanism (excentric mechanism, link mechanism, etc.) ) To convert the linear motion into a linear motion and drive the inner slide 3 up and down. The servomotor is used as the drive source and the main shaft is rotated by the servomotor. The rotational motion is linearly converted by a power conversion mechanism (such as an eccentric mechanism or a link mechanism) It is possible to adopt a servo drive system in which the inner slide 3 is driven to move up and down by converting it into a motion, or a system in which the inner slide 3 is directly driven up and down by a direct acting actuator such as a hydraulic cylinder or a linear motor.

In the configuration example of FIG. 1, the inner slide 3 is driven up and down via inner pitmans 23 a, 23 b, 23 c, and 23 d that constitute a part of the inner slide drive mechanism 20. The raising / lowering drive of the inner slide 3 is controlled by an inner slide control device (not shown).
The outer slide 7 is driven up and down via outer pitmans 25a, 25b, 25c, and 25d that constitute a part of the outer slide drive mechanism 30. The raising / lowering drive of the outer slide 7 is controlled by the outer slide control apparatus 50 (refer FIG.2 and FIG.3) mentioned later.

  As shown in FIG. 1A, inner slide points 27a, 27b, 27c, and 27d are provided on the upper surface of the inner slide 3, and the lower ends of the inner pitmans 23a, 23b, 23c, and 23d are rotatably connected. ing. Outer slide points 29a, 29b, 29c, and 29d are provided on the upper surface of the outer slide 7, and the lower ends of the outer pitmans 25a, 25b, 25c, and 25d are rotatably connected.

  In the illustrated example, a configuration including four sets of the outer slide drive mechanisms 30 will be described. Therefore, when identification is necessary, as shown in FIG. The subscripts a, b, c, and d are added, respectively. However, if there is no need to identify them in the explanation, the subscripts a, b, c, and d are omitted, and may be expressed as, for example, “servo motor 31”. is there.

  In order to adjust the distance in the height direction between the outer slide points 29a, 29b, 29c, 29d and the outer slide 7, slide adjusting devices 37a, 37b, 37c, 37d are provided on the upper portion of the outer slide 7. . The slide adjusting device 37 can be used, for example, to adjust the height of the outer slide 7 to be appropriate when the die 13 is changed. As the slide adjusting device 37, for example, a mechanism exemplified in “JIS Standard B0111 Press Machine—Terminology” can be used.

  FIG. 2 is a configuration diagram of the outer slide drive mechanism 30, (A) is a front view, and (B) is a side view. Servo motors 31a, 31b, 31c, and 31d are mounted on the crown 21. Small gears 33a, 33b, 33c, and 33d are connected to the output shafts of the servomotors 31a, 31b, 31c, and 31d so as to rotate with the rotation of the output shaft.

  The rotational motion of the servo motor 31 is converted into a lifting motion by the power conversion mechanism and output as a lifting motion of the outer slide 7. In the configuration example of FIG. 2, the power conversion mechanism is configured as an eccentric (eccentric) mechanism.

  The small gears 33a, 33b, 33c, and 33d mesh with the large gears 35a, 35b, 35c, and 35d, respectively. Each of the large gears 35a, 35b, 35c, and 35d rotates around an axis (not shown) whose position is fixed with respect to the crown 21.

  The upper ends of the outer pitmans 25a, 25b, 25c, and 25d are rotatably coupled to positions eccentric from the rotation centers of the large gears 35a, 35b, 35c, and 35d, thereby realizing an eccentric drive system. . 2 shows an arrangement in which the small gear 33 is located above the large gear 35, the small gear 33 may be located at any position as long as the large gear 35 can be driven. The mounting positions of the servo motors 31a, 31b, 31c, and 31d on the crown 21 may be any positions as long as the small gear can drive the large gear.

  Further, the arrangement of the plurality of outer slide drive mechanisms 30 is not limited to the configuration of FIG. 2 as long as it is mechanically established. For example, in FIG. 2, the outer slide drive mechanisms 30 are arranged so that they are mirror images of each other in the front-rear direction and in the left-right direction. Instead of this arrangement, all the outer slide drive mechanisms 30 have the same direction, These may be arranged by simply shifting the positions in the front-rear and left-right directions.

  FIG. 3 is a configuration diagram of the outer slide control device 50 for servo-controlling the servo motors 31a, 31b, 31c, and 31d in conjunction with the movement of the inner slide 3. The outer slide control device 50 controls the servo motor 31 so that the outer slide 7 moves up and down according to a predetermined operation pattern. Hereinafter, in order to distinguish the outer slide control device 50 between the first embodiment and the second embodiment, reference numeral “50A” is assigned to the control device in the first embodiment, and reference numeral is assigned to the control device in the second embodiment. Use “50B”.

  The drivers 41a, 41b, 41c, and 41d change the voltage and current supplied to the servomotors 31a, 31b, 31c, and 31d, respectively, so that the servomotors 31a, 31b, 31c, and 31d generate a desired torque. The rotation angles of the servo motors 31a, 31b, 31c, 31d are measured by motor rotary encoders 43a, 43b, 43c, 43d attached to the motor shafts. The position controllers 45a, 45b, 45c, and 45d receive the motor rotation angle command value and the motor rotation angle measured by the motor rotary encoders 43a, 43b, 43c, and 43d, and the motor follows the motor rotation angle command value. Torque command values to the drivers 41a, 41b, 41c, 41d are calculated so as to rotate.

  With the above configuration, servo control is performed so that the motor rotation angle follows the motor rotation angle command value. As shown in FIG. 2, the rotation of each servo motor 31 is caused to move up and down of the outer slide 7 via the power conversion mechanism. Since it is converted, the vertical position of the outer slide 7 also changes in conjunction with the motor rotation angle command value.

  In order to know the movement of the inner slide 3, the rotation angle of a crankshaft (not shown) that drives the inner slide 3 is measured by the inner slide crankshaft rotary encoder 51. The inner slide crankshaft rotation angle measured by the inner slide crankshaft rotary encoder 51 is input to the position command generator 53. The position command generator 53 receives the inner slide crankshaft rotation angle as an input, calculates a motor rotation angle command value corresponding to a desired position of the outer slide 7 corresponding thereto, and transmits it to the position controllers 45a, 45b, 45c, and 45d. To do.

  A combination of the servo motor 31 and the driver 41 is not limited as long as the torque of the servo motor 31 is variable. For example, a combination of a DC motor and a thyristor Leonard drive, a three-phase induction motor, or a permanent magnet type There is a combination of an AC motor such as a synchronous motor and a voltage-type inverter or current-type inverter that uses an IGBT, GTO, or power MOSFET as a power control element and performs power control by a pulse width modulation (PWM) method. As a system for controlling the motor to generate a desired torque, there are various vector controls including a current control in the case of a DC motor and a sensorless system in the case of an AC motor.

Examples of the rotary encoders 43 and 51 include an optical encoder that optically reads a pattern formed on a glass disk, and a resolver that uses a magnetic field.
As a calculation method of the torque command value in the position controller 45, feedback control such as PI control, PID control, and I-PD control can be used. Control characteristics may be improved by combining feedback control and feedforward control.

  As a configuration method of the position command generator 53, for example, a table storing motor rotation angle command values corresponding to an inner slide crankshaft rotation angle of 0 ° to 360 ° in increments of 1 ° is stored, and an inner slide is stored. When a crankshaft rotation angle is input, there is a method of calculating a motor rotation angle command value by referring to an entry in a table corresponding to the angle. Interpolation between table entries may be performed with a straight line, a quadratic curve, or the like so that the calculation result is smooth.

For signal transmission between blocks in FIG. 3, transmission by the number of pulses and pulse rate, analog transmission using voltage and current, transmission by a fieldbus using a communication protocol, transmission by a network, transmission by a shared memory, and the like are used.
The position controller 45 and the position command generator 53 can be configured by combining a memory or an input / output circuit with a CPU or DSP capable of real-time calculation.

  Hereinafter, in order to show the calculation formula, the power conversion mechanism is schematically shown as shown in FIG. 4, and the symbols are defined as follows.

(symbol)
θM: Motor rotation angle θG: Large gear rotation angle (The bottom dead center of the eccentric mechanism is 180 degrees)
N1: Number of teeth of small gear N2: Number of teeth of large gear R: Radius of movement of upper end of outer pitman L: Outer pitman length h: Height of lower end of outer pitman (upward is positive, bottom dead center is 0)
φ: Inner slide crankshaft rotation angle (bottom dead center of inner slide is 180 degrees)
h _in : Inner slide height (the upward direction is positive, and the bottom dead center height of the inner slide is 0)

Since the motor rotation angle is equal to the small gear rotation angle, the relational expression between the motor rotation angle and the large gear rotation angle is represented by the following expression 1.
(Formula 1)
θG = (N1 / N2) × θM

The relational expression between the large gear rotation angle and the outer pitman lower end height is expressed by the following expression 2.
(Formula 2)
h = R + L + R × cos (θG) − {L ² − (R × sin (θG)) ² } ^0.5

  For explanation, it is assumed below that R = 400 mm and L = 2000 mm. A graph showing the relationship between the large gear rotation angle θG and the outer pitman lower end height h is as shown in FIG. Although the relationship between the inner slide crankshaft rotation angle and the inner slide height is determined by the structure and dimensions of the mechanism that drives the inner slide 3, it is assumed that it is as shown in the graph of FIG. The gear ratio (N1 / N2) is assumed to be 1/7.

Construction and operation shown in FIG. 3, and the operation of the mechanism, corresponding to the inner slide crankshaft rotation angle phi, determined the outer pitman lower height h and the inner slide height h _in as shown in the flow in FIG. Since the lower end of the outer pit man is rotatably fixed to the outer slide 7 and moves freely, the change in the height of the outer slide 7 and the change in the value of h are the same, and the value of h is the height of the outer slide 7. It also shows changes.

When the relational expression shown in the graph of FIG. 8A is set as the relationship between the inner slide crankshaft rotation angle and the motor rotation angle command value in the position command generator 53, h and h _in with respect to the inner slide crankshaft rotation angle φ. This relationship is indicated by a solid line and a broken line in FIG. In FIG. 8 (B), the in interval period or _{h in} the inner slide 3 is descends _decreases, h is the lowest position when _{h in} is equal to or less than 200 mm (0 mm) i.e. the position for blank holder Therefore, the drawing process up to a depth of 200 mm is possible.

As a relationship between the inner slide crankshaft rotation angle and the motor rotation angle command value in the position command generator 53, a relational expression showing the graph in FIG. 9A is set instead of the relational expression showing the graph in FIG. 8A. If the relationship between h and h _in respect inner slide crankshaft rotation angle φ are as shown respectively in solid and dashed lines in FIG. 9 (B).

In FIG. 9 (B), the in interval period or _{h in} the inner slide 3 is descends _decreases, h is the lowest position when _{h in} is less than 100mm (0 mm) i.e. the position for blank holder Since there is, drawing processing to a depth of 100 mm is possible.

  Comparing FIG. 8B and FIG. 9B, the period in which the outer slide 7 is raised, that is, the section where h is 800 mm, the φ is in the range of 280 to 13 degrees in the former, whereas the latter Then, φ is as wide as 280 to 33 degrees. That is, the range of φ in which the workpiece 1 can be carried out from the die 13 and carried onto the die 13 is widened. That is, while the time during which the workpiece 1 can be unloaded from the die 13 and can be loaded onto the die 13 is kept constant, the time during which the inner slide crankshaft is stopped at the top dead center can be shortened, Since the rotation of the slide crankshaft can be made faster, the cycle time can be shortened. That is, by changing the relational expression between the inner slide crankshaft rotation angle and the motor rotation angle command value set in the position command generator 53 according to the drawing depth, cycle time is shortened and production capacity is improved. Can do.

  As described above, according to the present embodiment, since the operation of the outer slide 7 is controlled by the control of the servo motor, a simple link mechanism such as an eccentric mechanism can be used as the outer slide drive mechanism 30. This facilitates production, adjustment, and maintenance.

  In addition, the outer slide control device 50 stores a plurality of operation patterns related to the raising and lowering of the outer slide 7, and by changing the operation pattern according to the depth of the drawing process, it is possible to reduce the wrinkle holding time for a deep object. If it is long and shallow, the wrinkle holding time can be shortened. That is, the wrinkle holding time can be shortened according to the object to be drawn, so that the cycle time is shortened and the productivity is improved.

[Second Embodiment]
FIG. 10 is a configuration diagram of an outer slide control device 50B in the double-action press machine according to the second embodiment of the present invention. The second embodiment differs from the first embodiment in the configuration of the outer slide control device 50B for controlling the servo motor. The entire configuration of the double-acting press machine other than the outer slide control device 50B may be the same as that of the first embodiment.

  In the present embodiment, the outer slide drive mechanism 30 raises and lowers the outer slide 7 so as to perform wrinkle pressing of the workpiece 1 at a position above the bottom dead center of the outer slide drive mechanism 30. The outer slide control device 50B controls the servo motors 31a, 31b, 31c, and 31d so as to generate a desired wrinkle pressing force while the work 1 is wrinkled.

  As shown in FIG. 10, one of the wrinkle pressing torque command values from the wrinkle pressing force indicators 61a, 61b, 61c and 61d and the position control torque command values from the position controllers 45a, 45b, 45c and 45d. One is selected by the torque command value selectors 63a, 63b, 63c, and 63d, and is used as a torque command value to the drives 41a, 41b, 41c, and 41d. Which value is selected by the torque command value selectors 63a, 63b, 63c, and 63d is designated by a torque command value switching signal output from the position command generator 53.

  In order to perform wrinkle holding without moving the outer slide 7 to the bottom dead center, as shown in the graph of FIG. 11A, the inner slide crank is rotated so that the rotation direction of the servo motor 31 is reversed when the outer slide 7 is lowered and raised. The relationship between the shaft rotation angle and the motor rotation angle command value is set in the position command generator 53.

  Further, as shown in FIG. 11C, the position command generator 53 is a position where the outer slide 7 is most lowered, that is, a range in which h is minimum (a position where wrinkle pressing is performed. In this example, φ is 132 to 180 degrees. 1) as a torque command value switching signal, and 0 as a torque command value switching signal in other ranges. However, the torque command value selectors 63a, 63b, 63c, 63d select the wrinkle-pressing torque command value if the torque command value switching signal is 1, and select the position control torque command value if the torque command value switching signal is 0. The torque command value is output to the drives 41a, 41b, 41c and 41d.

  In the range where the torque command value switching signal is 0 (in this example, φ is smaller than 132 degrees), the torque command value selectors 63a, 63b, 63c, and 63d select the torque command value for position control. The same servo control as that of the form is performed, and the outer slide 7 is lowered.

  When the torque command value switching signal is in the range of 1 (in this example, φ is in the range of 132 to 180 degrees), the wrinkle pressing force indicators 61a, 61b, 61c, and 61d are calculated as shown in the following (Equation 6). Torque command value tM to be pressed and torque command value selectors 63a, 63b, 63c, and 63d select the wrinkle pressing torque command value, so that torque command values to the drives 41a, 41b, 41c, and 41d are selected. The value of is tM.

  The drives 41a, 41b, 41c, 41d supply current / voltage to the motors 31a, 31b, 31c, 31d, and the motors 31a, 31b, 31c, 31d generate torque tM. The torque of the motor generates a wrinkle pressing force f through the mechanism, and wrinkle pressing is performed.

  In a range where the torque command value switching signal is again 0 (in this example, φ is greater than 180 degrees), the torque command value selectors 63a, 63b, 63c, and 63d select the position control torque command value. The same servo control as in the first embodiment is performed, and the outer slide 7 moves up.

(a formula)
Symbol tM: Motor torque tG: Large gear torque f: Force generated by the lower end of the outer pit man downward (that is, wrinkle holding force)
t: The value of θM at the position where wrinkle pressing is performed (equal to the value of the motor rotation angle command value; 1120 degrees in this example)
ΘG: θG value at the position where wrinkle pressing is performed

Since the motor rotation angle is equal to the small gear rotation angle, the relationship between the motor torque and the large gear torque is expressed by the following Expression 3 with reference to (Expression 1).
(Formula 3)
tG = (N2 / N1) × tM

The relational expression between the large gear torque and the force generated by the lower end of the outer pitman downward is as shown in Expression 4 below.
(Formula 4)
dθG × tG = −dh × f
(D indicates differentiation)

Substituting the derivative of (Equation 2) into (Equation 4) and substituting ΘG into θG,
(Formula 5)
tG = [R × sin (ΘG) −R ² × sin (ΘG) × cos (ΘG) / {L ² − (R × sin (ΘG)) ² } ^0.5 ] × f

When (Equation 5) is substituted into (Equation 3), the following value may be output as the wrinkle pressing torque command value when the wrinkle pressing force f to be generated is given.
(Formula 6)
tM = (N1 / N2) × [R × sin (ΘG) −R ² × sin (ΘG) × cos (ΘG) / {L ² − (R × sin (ΘG)) ² } ^0.5 ] × f
However, ΘG = (N1 / N2) × ΘM

  The wrinkle holding force may be different or the same at the four points on the left front, right front, left rear, and right rear. If they are different, tMa, tMb, tMc, and tMd are calculated by using (Equation 6) for the wrinkle pressing forces fa, fb, fc, and fd that are to be generated, and these are calculated as wrinkle pressing force indicators 61a and 61b. , 61c, 61d.

  The wrinkle pressing force f may be constant during wrinkle pressing or may be changed with time. For example, it may be changed in conjunction with the value of φ. In this case, tM1, tM2, tM3,... Are calculated according to (Equation 6) for the f values f1, f2, f3,... Changing, and the crease pressing force indicators 61a, 61b, 61c are calculated. , 61d.

  In the second embodiment, the value of the outer pitman lower end height h at the position where wrinkle pressing is performed is higher than that in the first embodiment, but the slide adjusting devices 37a, 37b, 37c, and 37d are moved by a distance corresponding to the difference in the value of h. By using and lowering the outer slide 7, the height of the outer slide 7 becomes the same as that of the first embodiment, and the blank holder 9 can sandwich the work 1 between the die 13 and generate a wrinkle holding force.

  If the counter balance (not shown) cannot completely cancel the weight of the blank holder 9 or the outer slide 7, or if the force is lost due to mechanical loss, it is equivalent to the weight and lost force that cannot be offset. Then, the value of f is increased or decreased, and the wrinkle pressing torque command value is calculated according to (Equation 6).

  According to the above-described configuration of the second embodiment of the present invention, the wrinkle pressing force is controlled by controlling the torque of the servo motor. Therefore, in order to control the wrinkle pressing force, the pneumatic pressure is set in the outer slide 7 having a small space. There is no need to install equipment or hydraulic equipment. For this reason, manufacture, adjustment, and maintenance become easy. In addition, the wrinkle holding force can be changed during wrinkle pressing by changing the torque of the servo motor with time.

  Further, if the servo motors 31a, 31b, 31c, 31d are individually controlled in the plurality of outer slide drive mechanisms 30, the wrinkle pressing force can be adjusted according to the position, so that the molding quality can be improved.

[Modification]
The shape of the graph representing the positional relationship between the rotation angle and the inner slide / outer slide differs depending on the dimensions and structure of the eccentric mechanism and link mechanism, but if the position of the inner slide / outer slide is uniquely determined with respect to the rotation angle The present invention can be applied.

Also in the first embodiment, as in the second embodiment, the outer slide may be moved up and down by rotating the servo motor 31 forward and backward. In this case, it is not necessary to pass the top dead center / bottom dead center of the outer slide drive mechanism 30.
In the configuration example shown in FIGS. 1 and 2, the connection by the pitman is adopted as a connection method between the outer slide drive mechanism 30 and the outer slide 7, but a connection using a plunger may be used.

  In the configuration examples of FIGS. 1 and 2, the connection point between the inner slide drive mechanism 20 and the inner slide 3 and the connection point between the outer slide drive mechanism 30 and the outer slide 7 are all 4 points. It may be other than 4 points. For example, two points or one point may be used, and the number of points may be different between the inner slide and the outer slide.

In the outer slide drive mechanism 30, large gears (35 a and 35 c, 35 b and 35 d) that are separated from each other on the left and right sides are connected by a shaft and another gear is added to the left and right large gears (35 a and 35 b). , 35c and 35d) may be linked. In this case, the outer slide drive mechanism 30 interlocked by a shaft or gear can be driven by one servomotor, and the number of motors can be reduced.
Further, the following configuration is also possible.
(A) The left front and left rear large gears (35a and 35c) are connected and interlocked with the left shaft, and the right front and right rear large gears (35b and 35d) are connected and interlocked with the right shaft, and the outer The slide drive mechanism 30 can be driven by two servo motors on the left and right.
(B) The left front and right front large gears (35a and 35b) are linked via a gear added to the front side, and the left rear and right rear large gears (35c and 35d) are linked via a gear added to the rear side. The outer slide drive mechanism 30 can be driven by two front and rear servo motors.

As the servo motor 31, a motor having a high rotational speed may be used, and the rotational speed may be reduced using a gear type or planetary gear type speed reducer to drive the small gear.
Further, a small gear may be fixed to the motor shaft through a coupling in order to facilitate manufacture, adjustment, and maintenance.

The power conversion mechanism in the outer slide drive mechanism 30 may be a mechanism other than the eccentric type (link type, crank type, crankless type, screw type, etc.).
Further, as the servo motor 31 in the outer slide drive mechanism 30, a linear servo motor may be employed instead of the rotary motor. In this case, the power conversion mechanism may be eliminated, and the outer slide may be directly driven up and down by linear driving of the linear servo motor.

  Instead of measuring the rotation angle of the motor shaft with the rotary encoder and converting it to the height of the outer slide 7 using a conversion formula determined by the structure of the outer slide drive mechanism 30, the rotation angle of the large gear 35 is measured with the rotary encoder. The height of the outer slide 7 may be converted using a conversion formula determined by the structure of the slide drive mechanism 30. Further, the height of the outer slide 7 may be directly measured by a linear displacement meter such as a magnetostrictive linear encoder or a linear scale.

As a means for knowing the movement of the inner slide 3 in order to synchronize the outer slide 7 with the movement of the inner slide 3, the following method is adopted in addition to the method of measuring the inner slide crankshaft rotation angle with a rotary encoder. May be.
(A) A shaft (hereinafter referred to as a driven shaft) that is mechanically connected to the inner slide crankshaft by a gear, a timing belt, or the like is provided, and this driven shaft is connected to the inner slide crankshaft in a fixed positional relationship (one-to-one). (There may be deceleration or acceleration), and the rotation angle of the driven shaft is measured with a rotary encoder, and the reduction ratio is multiplied to convert it to the rotation angle of the inner slide crankshaft. To do.
(B) The inner slide height is measured with a linear displacement meter.
(C) Estimate from a command signal for driving the inner slide crankshaft. For example, the position of the inner slide 3 is estimated from a signal instructing connection / disconnection of the clutch and a speed command value to the motor for driving the flywheel.

  Although the embodiments of the present invention have been described above, the embodiments of the present invention disclosed above are merely examples, and the scope of the present invention is not limited to these embodiments. . The scope of the present invention is indicated by the description of the scope of claims, and further includes meanings equivalent to the description of the scope of claims and all modifications within the scope.

It is a lineblock diagram of the double action press machine concerning a 1st embodiment of the present invention. It is a block diagram of an outer slide drive mechanism. It is a block diagram of the outer slide control apparatus which controls a servomotor. It is the figure which modeled the power conversion mechanism. It is a graph which shows the relationship between large gear rotation angle (theta) G and outer pit man lower end height h. It is a graph showing the relationship between the inner slide crankshaft rotation angle φ and the inner slide height h _in. It is a flowchart which shows the procedure _in which outer pit man lower end height h and inner slide height hin are determined. (A) is a graph showing an example of the relationship between the inner slide crankshaft rotation angle φ and the motor rotation angle command value. (B) is a graph showing an example of the relationship between h and h _in respect inner slide crankshaft rotation angle phi. (A) is a graph which shows another example of the relationship between an inner slide crankshaft rotation angle (phi) and a motor rotation angle command value. (B) is a graph showing another example of the relationship between h and h _in respect inner slide crankshaft rotation angle phi. It is a block diagram of the control apparatus in the double acting press machine which concerns on 2nd Embodiment of this invention. (A) is a graph which shows an example of the relationship between the inner slide crankshaft rotation angle (phi) and motor rotation angle command value in 2nd Embodiment. (B) is a graph showing an example of the relationship between h and h _in respect inner slide crankshaft rotation angle φ in the second embodiment. (C) is a graph showing an example of the relationship between the inner slide crankshaft rotation angle φ and the torque command value switching signal in the second embodiment.

Explanation of symbols

1 Work 3 Inner Slide 5 Punch 7 Outer Slide 9 Blank Holder 11 Bolster 13 Die 15 Bed 17 Upright 20 Inner Slide Drive Mechanism 21 Crown 23a, 23b, 23c, 23d Inner Pit Man 25a, 25b, 25c, 25d Outer Pit Man 27a, 27b , 27c, 27d Inner slide point 29a, 29b, 29c, 29d Outer slide point 30 Outer slide drive mechanism 31a, 31b, 31c, 31d Servo motors 33a, 33b, 33c, 33d Small gears 35a, 35b, 35c, 35d Large gear 37a , 37b, 37c, 37d Slide adjustment devices 41a, 41b, 41c, 41d Drivers 43a, 43b, 43c, 43d Motor rotary encoders 45a, 45b, 45c, 45d Position controller 50, 50A, 50B Outer slide control device 51 Inner slide crankshaft rotary encoder 53 Position command generator 61a, 61b, 61c, 61d Wrinkle pressing force indicator 63a, 63b, 63c, 63d Torque command value selector

Claims (4)

In a double-action press machine provided with an outer slide in which a blank holder for pressing a workpiece is installed on the lower surface and driven up and down, and an inner slide in which a punch is installed on the lower surface and driven up and down inside the outer slide,
An outer slide drive mechanism that has a servo motor and drives the outer slide up and down using the servo motor as a drive source;
An outer slide control device that controls the servo motor so that the outer slide moves up and down according to a predetermined operation pattern.   The double-acting press machine according to claim 1, wherein the outer slide control device stores a plurality of operation patterns having different wrinkle holding times with respect to an ascending / descending operation of the outer slide. The outer slide drive mechanism raises and lowers the outer slide so as to perform wrinkle pressing of the workpiece at a position above the bottom dead center of the outer slide drive mechanism,
The double-acting press machine according to claim 1 or 2, wherein the outer slide control device controls the servo motor so as to generate a desired wrinkle pressing force while the wrinkle pressing of the workpiece is performed. A plurality of outer slide drive mechanisms;
The double-acting press machine according to claim 3, wherein the outer slide control device individually controls a servo motor of each outer slide drive mechanism.

Images