JP2007283332A - Method and apparatus for press work - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently carry out press work and other work at one station. <P>SOLUTION: An apparatus 10 for press work carries out the press work for a steel plate 12 by approaching an upper die 38 to a lower die 52 by the operation of a servomotor 24. The driving portion 16a of a press stops the upper die 38 at the bottom dead point by referring a signal from a first linear sensor 36. When the upper die 38 is stationary at the bottom dead point, piercing work is carried out to an additional working portion 12a of the steel plate 12 to be exposed to an exposure hole 42 of the upper die 38 by projecting a piercing tool 82 from side by means of a cylinder 80 of an additional working machine 22. After the piercing work, the upper die 38 is lifted. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a press processing method and a press processing apparatus for servo press forming a press-formed product.

  In a conventional mechanical press, a slide connected to a crankshaft is driven up and down by a crankshaft rotating motor to perform press working. In such a mechanical press, since the mold is continuously moved up and down, it is difficult to change the speed according to the processing conditions or to temporarily stop the mold.

  From such a background, recently, a servo press capable of flexibly controlling the operation of a mold using a servo motor has been used (for example, see Patent Document 1 and Patent Document 2). In such a servo press, the die can be stopped at a predetermined position during one stroke in which the die moves up and down.

JP 2001-150200 A Japanese Patent No. 3537287

  Incidentally, the press-molded product may be subjected not only to a single press-molding but also to other processes (for example, piercing or embossing) incidentally. In the press work described in, no additional work other than the press is performed. Therefore, in addition to the press processing device, another independent processing device must be provided to perform processing, and the processing man-hours, processing cost and processing device installation space increase, and means for conveying a workpiece between the processing devices is required.

  The present invention has been made in consideration of such problems, and provides a press working method and a press working apparatus capable of efficiently processing a plate material that requires processing other than press processing. With the goal.

  The press working method according to the present invention is a press working method in which a press-formed product is formed by a servo press. The press forming step of pressing a plate material by bringing a first die close to a second die, After the press molding process, the bottom dead center stop process for stopping the positions of both molds when both molds approach each other and the plate pressed by both molds during the bottom dead center stop process. And an additional processing step for performing other processing.

  In this way, pressing and other processing are continuously performed in one station by performing other processing on the plate material while stopping the positions of both types when the bottom dead center is approaching. Can be done efficiently.

  In this case, after the press molding, the operation timing of the control in the bottom dead center stopping step and the additional processing step is set in the control means for controlling the first die to be close to the second die. Then, the additional processing is accurately synchronized with the press processing.

  The press working apparatus according to the present invention is a press working apparatus that performs servo press control, and additional processing means for additionally processing the press forming part exposed from the mold, and the first mold as the second mold. After pressing the plate material with both molds, both molds were pressed by the two additional molds when both molds were stopped when both molds reached the bottom dead center. And a control means for performing other processing on the plate material.

  In this way, when both molds approach the bottom dead center, both the molds are stopped while the other materials are applied to the plate material, so that pressing and other processes are performed continuously in one apparatus. Can be done efficiently.

  In this case, when the control unit further controls the first die to be close to the second die, the additional processing is accurately synchronized with the press processing.

  According to the press processing method and the press processing apparatus according to the present invention, by performing other processing on the plate material while stopping the positions of both molds when both molds approach the bottom dead center, press processing and Other processes can be performed continuously in one station, which is efficient.

  Moreover, it is not necessary to provide other independent processing devices in addition to the press processing device, and the processing man-hours, processing costs and processing device installation space can be suppressed, and no means for conveying workpieces between the processing devices is required. It is.

  Hereinafter, the press working method and the press working apparatus according to the present invention will be described with reference to the accompanying FIGS.

  As shown in FIG. 1, a press working apparatus 10 according to the present embodiment is for performing press working of a steel plate (plate material) 12 as a workpiece and piercing as an additional work, and performs the working. It has a main body 14 and a control unit 16 that controls the apparatus main body 14.

  The apparatus main body 14 includes an upper mold mechanism 18, a lower mold mechanism 20, and an additional processing machine 22. The upper mold mechanism 18 includes a servo motor 24 as a drive source, a reduction gear 26 that is rotationally driven by the servo motor 24, a rotary plate 28 that is rotationally driven by the reduction gear 26 with a large torque, and the rotary plate 28. The connecting rod 30 is pivotally supported on the side surface thereof so that the upper end portion thereof is swingable. The servo motor 24 is, for example, an AC type, and has high responsiveness and small torque unevenness. The shaft rotation position of the servo motor 24 is detected by the encoder 24 a and supplied to the control unit 16.

  The upper mold mechanism 18 further detects the position of the slider 32 supported by the lower end of the connecting rod 30, a plurality of (for example, four) rails 34 for guiding the slider 32 in the vertical direction, and the position of the slider 32. The first linear sensor 36 to be supplied to the control unit 16 and an upper mold (first mold) 38 provided on the lower surface of the slider 32 are included.

  The upper mold 38 is pressed by pressing the steel plate 12 together with the lower mold (second mold) 52, and a mold surface 38 a for contacting the upper surface of the steel plate 12 is provided on the lower surface. Further, around the upper die 38, an annular holder 40 is slightly protruded so as to prevent wrinkles and misalignment when the steel plate 12 is pressed. Therefore, the holder 40 comes into contact with the steel plate 12 ahead of the mold surface 38a. The lower surface of the holder 40 has a shape corresponding to the molding shape, and is set to a horizontal plane, for example.

  Further, the upper die 38 is provided with an exposure hole 42 for exposing the additional machining portion 12a in the steel plate 12 after the press working to the upper die 38 so as to be processed by the additional processing machine 22. The exposure hole 42 opens toward the right side in FIG. 1, for example, and when the upper die 38 is processed to the bottom dead center (that is, the lowest point during one stroke of the upper die 38), the steel plate Twelve additional machining points 12 a (see FIG. 4) are arranged at positions where they are exposed to the additional machine 22. The exposure hole 42 is provided in the holder 40, for example. The exposure hole 42 may be in a shape that exposes the additional processing portion 12a, and may be, for example, a U-shaped notch.

  The lower mold mechanism 20 includes a fixed base 50 that serves as a base, a lower mold 52 provided on the upper part of the fixed base 50, an annular blank holder 54 that supports the periphery of the steel plate 12, and the blank holder 54 that moves up and down. A die cushion mechanism 56. The blank holder 54 is provided at a position facing the holder 40, and the holder 40 is for holding the end of the steel plate 12 together.

  The lower mold 52 is pressed by pressing the steel plate 12 together with the upper mold 38, and a mold surface 52a for contacting the lower surface of the steel plate 12 is provided on the upper surface. The mold surface 52a is formed in a shape corresponding to the mold surface 38a. Further, the lower mold 52 is provided with a hole 58 at a position corresponding to the additional processing portion 12a in the steel plate 12 after being pressed. The hole 58 is set to have a diameter corresponding to the piercing hole 140 (see FIG. 5) provided in the additional processing portion 12a. The hole 58 is provided at a position facing the additional processing machine 22, and is provided, for example, on the side surface of the lower mold 52.

  The die cushion mechanism 56 connects, from below, a plurality of pins 60 that pass through the fixing base 50 and the attachment portion 52b of the lower mold 52 and are fixed to the lower portion of the blank holder 54, and the lower ends of these pins 60. A plate 62, a plurality of cylinders 64 for moving the plate 62 up and down, and a second linear sensor 66 that detects the position of the plate 62 and supplies it to the control unit 16.

  The die cushion mechanism 56 further includes a hydraulic motor 68 that supplies / recovers pressure oil to / from the cylinder 64 and a servo motor 70 that rotates the hydraulic motor 68. The rotation of the servo motor 70 is transmitted to the hydraulic motor 68 via a transmission unit 72 including a coupling, a speed reducer, and the like. The hydraulic motor 68 rotates in both forward and reverse directions under the action of the servo motor 70, and can selectively supply pressure oil to the rod side and the cap side of the cylinder 64. Thus, the wrinkle pressing can be performed by appropriately pressing the peripheral portion of the steel plate 12 with the holder 40 and the blank holder 54 while performing the predetermined pressure control.

  The additional processing machine 22 includes a cylinder 80 and a piercing tool 82 provided at the tip of a rod 80a of the cylinder 80. The piercing tool 82 is set to have a diameter corresponding to the piercing hole 140 and the hole 58 provided in the additional processing portion 12a. The cylinder 80 is set in a direction in which the piercing tool 82 passes through the additional machining portion 12a and is inserted into the hole 58 when the rod 80a is advanced.

  The control unit 16 refers to a signal supplied from the encoder 24 a and the first linear sensor 36, a press drive unit 16 a that drives and controls the servo motor 24, an additional processing machine drive unit 16 b that drives and controls the cylinder 80, 2 A die cushion drive unit 16c that raises and lowers the blank holder 54 by driving the servo motor 70 while referring to a signal supplied from the linear sensor 66. The press drive unit 16a, the additional processing machine drive unit 16b, and the die cushion drive unit 16c are connected to each other and can be operated synchronously.

  As shown in FIG. 2, the press driving unit 16 a uses a servo power unit 104 that is supplied after the power obtained from the power source 100 is boosted by the transformer 102, and servo power using the power adjusted by the servo power unit 104. And a servo amplifier 106 for driving the motor 24. In the servo amplifier 106, the drive amount of the servo amplifier 106 is set under the action of the software function unit 108. A large-capacitance capacitor 110 is provided between the servo power supply unit 104 and the servo amplifier 106.

  The die cushion drive unit 16 c includes a servo power supply unit 112 to which the power of the power supply 100 is supplied, and a servo amplifier 114 that drives the servomotor 70 using the power adjusted by the servo power supply unit 112. In the servo amplifier 114, the drive amount of the servo motor 70 is set under the action of the software function unit 116.

  The servo power supply unit 112 and the servo amplifier 114 can energize both in the forward and reverse directions. When the servo motor 70 is rotated by a load to generate power, the current obtained by power generation is supplied to the press drive unit 16a. A regenerative operation is possible. The regenerative power is stored in the large-capacity capacitor 110 and used for driving the servo motor 24, so that the capacity of the power supply facility can be suppressed.

  Next, a method for processing the steel plate 12 as a workpiece using the press working apparatus 10 configured as described above will be described.

  First, initial setting is performed in step S1 of FIG. That is, the blank holder 54 is raised to a predetermined position, and the blank steel plate 12 is supported by the blank holder 54. Further, the rod 80a of the cylinder 80 in the additional processing machine 22 is retracted, and the upper die 38 is raised to the top dead center.

  In step S2, the servo motor 24 is rotationally driven to lower the slider 32 under the action of the press drive unit 16a.

  When lowered to some extent, the holder 40 comes into contact with the upper surface of the steel plate 12, and the steel plate 12 is held between the holder 40 and the blank holder 54. From this point (see displacement x3 in FIG. 7A), the blank holder 54 is lowered under the action of the die cushion drive unit 16c (step S3). The die cushion drive unit 16c performs pressure control so that the blank holder 54 is lowered while generating an appropriate force so that the lower surface of the steel plate 12 is pressed and holding the steel plate 12 securely. That is, the blank holder 54 is pressed through the steel plate 12 by the holder 40 and is pressed down while applying an appropriate pressure to the steel plate 12.

  As a result, the steel plate 12 is lowered while the peripheral portion is held by the holder 40 and the blank holder 54, and is gradually pressed into a product shape by the upper die 38 and the lower die 52.

  Further, when the blank holder 54 is lowered, the servo motor 70 may generate electric power and perform the above regenerative operation.

  In step S <b> 4, the press driving unit 16 a refers to the signal of the first linear sensor 36 and confirms whether or not the position of the slider 32 has reached the bottom dead center. When the slider 32 reaches the bottom dead center, the process proceeds to step S5, and when it does not reach, the descent continues.

  In step S5, the lowering of the slider 32 and the lowering of the blank holder 54 are stopped. At this time, as shown in FIG. 4, the steel plate 12 is sandwiched between the mold surface 38 a of the upper mold 38 and the mold surface 52 a of the lower mold 52, and the press work is finished. Further, the exposure hole 42 of the upper die 38 is arranged coaxially with the piercing tool 82 and the hole 58, and the additional processing portion 12 a is exposed as viewed from the additional processing machine 22.

  In step S6, the rod 80a of the cylinder 80 is advanced under the action of the additional processing machine drive unit 16b, and the piercing tool 82 passes through the additional processing portion 12a through the exposure hole 42 as shown in FIG. The pierce hole 140 is formed by inserting. Chips 130 generated as a result of forming the piercing holes 140 are dropped and collected at a predetermined collection location, or are discharged by a dust collector (not shown).

  The rod 80a is set so that the piercing hole 140 is formed when the rod 80a is advanced to the maximum. Further, a linear sensor, a limit switch, or the like may be provided to control to advance to an appropriate position where the piercing hole 140 is formed and stop while referring to the advance distance of the rod 80a.

  In step S7, the rod 80a and the piercing tool 82 are retracted to their original positions.

  In step S8, the servo motor 24 is rotationally driven to raise the slider 32 under the action of the press drive unit 16a. At this time, the blank holder 54 is kept stopped.

  In step S9, it is confirmed whether or not the position of the slider 32 has reached the panel transport position. If it has reached, the process proceeds to step S10, and if not, the slider 32 continues to rise.

  In step S10, the blank holder 54 is raised under the action of the die cushion drive unit 16c. As a result, the blank holder 54 rises slightly later than the slider 32.

  In step S11, the die cushion drive unit 16c checks whether or not the position of the blank holder 54 has reached the panel transport position. When the blank holder 54 has reached the panel transport position, the process proceeds to step S12, and when it has not reached, the ascent continues.

  In step S12, as shown in FIG. 6, the raising of the blank holder 54 is temporarily stopped, and the steel plate 12 subjected to the press working and the piercing process is transported to a station of the next process (for example, a welding process) by a predetermined transport means. .

  In step S13, the die cushion drive unit 16c raises the blank holder 54 again.

  In step S14, the die cushion drive unit 16c checks whether or not the position of the blank holder 54 has reached the processing standby position. When the blank holder 54 reaches the processing standby position, the process proceeds to step S15.

  In step S15, the raising of the blank holder 54 is stopped, and the unprocessed steel plate 12 is arranged at a predetermined position. During this time, the slider 32 continues to rise.

  In step S <b> 16, the press driving unit 16 a refers to the signal of the first linear sensor 36 and confirms whether or not the position of the slider 32 has reached the top dead center. When the slider 32 has not reached the top dead center, the ascent is continued. When the slider 32 has reached the top dead center, the current process shown in FIG. When the slider 32 reaches the top dead center, the slider 32 may be stopped once in view of the cycle time with other processes. In particular, when there is no influence of other processes, the slider 32 is not stopped and is stopped as it is. Processing of the next steel plate 12 may be continued.

  The above processing is shown in one flowchart, but for example, the drive units of the press drive unit 16a, the additional processing machine drive unit 16b, and the die cushion drive unit 16c operate independently while performing mutual synchronization confirmation. May be.

  The above-described series of processing cycles are represented by time charts as shown in FIGS. 7A to 7C. In these FIG. 7A-FIG. 7C, the step number in said process is attached | subjected to the location corresponding to the horizontal axis of time.

  As shown in FIG. 7A, the displacement x of the slider 32 reciprocates between the top dead center x1 and the bottom dead center x2, and stops at the bottom dead center x2 for a predetermined time (between steps S5 and S8). . Further, at the time corresponding to step S <b> 3, the holder 40 has reached the displacement x <b> 3 in contact with the upper surface of the steel plate 12. The displacement x4 at the time of step S10 is a panel conveyance position, which is a position corresponding to the displacement y3 of the blank holder 54.

  As shown in FIG. 7B, the displacement y of the blank holder 54 is stopped at the processing standby position y1 during the period corresponding to steps S1 to S3 and the period after step S15. Further, during steps S5 to S10 in which the slider 32 is stopped at the bottom dead center x2, the blank holder 54 is also stopped at the position of the displacement y2. During steps S3 to S5, during the periods of steps S10 to S12 and S13 to S15, the blank holder 54 is raised and lowered at substantially the same speed as the slider 32. During the period from step S10 to step S11, the blank holder 54 is stopped at the panel transport position y3.

  As shown in FIG. 7C, the displacement z of the piercing tool 82 stops at the standby position z1 in the period from step S1 to S5 and step S8. The piercing tool 82 starts to advance from S6 immediately after step S5, and abuts and punches the additional machining point 12a at the displacement z2 to reach the maximum displacement z3. Thereafter, in step S7, the process returns to the standby position z1.

  As described above, according to the press processing method and the press processing apparatus 10 according to the present embodiment, when both the upper mold 38 and the lower mold 52 reach the bottom dead center where they are close, the positions of both molds are stopped. However, by performing piercing on the steel plate 12, the press working and the piercing can be performed continuously in one station, which is efficient.

  Further, it is not necessary to provide another independent piercing apparatus in addition to the press processing apparatus 10, and the processing man-hours, processing costs, and processing apparatus installation space can be suppressed. Since pressing and piercing are performed in one station, there is no need to carry the steel plate 12 between the pressing and piercing.

  Further, in the processing by the additional processing machine 22, basically any processing is possible as long as it is a portion exposed by the exposure hole 42, and for example, engraving, laser marker, embossing, etc. can be performed. . Since the processing by the additional processing machine 22 is not affected by the pressing direction of the upper die 38, the processing can be performed from an arbitrary direction depending on the design conditions as long as the portion is exposed by the exposure hole 42.

  Furthermore, when performing the processing by the additional processing machine 22, it is in a stable state in which the material flow by the press processing is finished, and the steel plate 12 is stably restrained by the upper die 38 and the lower die 52, Generation of burrs and the like is suppressed, and accurate and highly accurate machining is possible. Since the piercing tool 82 processes the steel plate 12 in a stable state, the service life is improved. In addition, since the processing by the additional processing machine 22 is performed while the upper die 38 is stopped, stable and accurate processing is possible.

  The control unit 16 performs integrated control of bringing the upper die 38 close to the lower die 52 and operation control of the additional processing machine 22, and the additional processing is accurately synchronized with the press processing.

  The press working method and the press working apparatus according to the present invention are not limited to the above-described embodiments, and it is needless to say that various configurations can be adopted without departing from the gist of the present invention.

It is a schematic diagram which shows the structure of the press work apparatus which concerns on this Embodiment. It is a block block diagram of a press drive part and a die cushion drive part. It is a flowchart which shows the procedure of the press work method which concerns on this Embodiment. It is a partial cross-sectional enlarged view of a part of an upper die, a part of a lower die, an additional processing portion of a steel plate, and an additional processing machine when a slider stops at bottom dead center. FIG. 5 is a partial cross-sectional enlarged view showing a state in which piercing is performed by advancing a piercing tool with an additional processing machine from the state shown in FIG. 4. It is a schematic diagram of the press processing apparatus of the state which suspended the raise of the blank holder at the panel conveyance position. FIG. 7A is a graph showing the displacement of the slider in one cycle, FIG. 7B is a graph showing the displacement of the blank holder in one cycle, and FIG. 7C is a graph showing the displacement of the piercing tool in one cycle.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Press processing apparatus 12 ... Steel plate 12a ... Additional processing location 14 ... Apparatus main body 16 ... Control part 22 ... Additional processing machine 24,70 ... Servo motor 24a ... Encoder 32 ... Slider 38 ... Upper mold | type 38a, 52a ... Mold surface 42 ... Exposed hole 52 ... Lower mold 56 ... Die cushion mechanism 58 ... Hole 64, 80 ... Cylinder 82 ... Piercing tool
x1 ... Top dead center x2 ... Bottom dead center

Claims (4)

In the press processing method that forms press-formed products with a servo press,
A press molding step in which the first die is brought close to the second die and the plate material is pressed;
After the press molding step, a bottom dead center stop step of stopping the positions of both molds when reaching the bottom dead center where both molds are close to each other;
During the bottom dead center stopping step, an additional processing step of performing other processing on the plate material pressed by both molds,
A press working method characterized by comprising: The press working method according to claim 1,
After the press molding, the operation timing of the control in the bottom dead center stopping step and the additional machining step is set in a control means for controlling the first die to be close to the second die. A press working method characterized by the above. In press processing equipment that performs servo press control,
Additional processing means for additionally processing the press-molded part exposed from the mold;
After the first mold is brought close to the second mold and the plate material is press-molded by both molds, the additional processing is performed in a state where both molds are stopped when reaching the bottom dead center where both molds are close to each other. Control means for causing the means to perform other processing on the plate material pressed by both molds;
A press working apparatus comprising: The press working apparatus according to claim 3,
The said control means is further controlled to make the said 1st type | mold close to the said 2nd type | mold, The press work apparatus characterized by the above-mentioned.

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