JP3097053B2 - Bottom dead center position correction device for each process of transfer press - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bottom dead center position correcting apparatus for correcting a change in a bottom dead center position of a slide relative to a bolster due to a thermal displacement of a transfer press by correcting only a punch holder necessary for processing accuracy. .

[0002]

2. Description of the Related Art Conventionally, the bottom dead center position of a slide 101 relative to a bolster 102 in a transfer press as shown in FIG. 9 changes due to thermal expansion as the operation is continued. Therefore, the upper table 1 for the lower table 103 of the lower die set
Since the position of position 04 also changes, when forming a workpiece having a strict allowable dimension range, the temperature rise reaches a saturation point a predetermined time after starting, and the amount of change in the bottom dead center position of the slide 104 due to thermal displacement decreases. At this point, by adjusting the vertical position of the punch holder 105 in the step of forming a strict portion of the allowable dimension range, the predetermined position of the punch (not shown) attached to the punch holder 105 for the die (not shown) in the lower table 103 is adjusted. At present, defective workpieces that have been adjusted and formed during the period from the start to the predetermined time are discarded.

[0003]

The method of adjusting the vertical position of the punch holder in a process necessary for processing accuracy as described in the prior art at the time when the temperature rise reaches the saturation point is a method for adjusting the mechanical strength of the punch holder after a predetermined time has elapsed from the start. Must be stopped and the vertical position of the punch holder must be adjusted, so that there is a problem that the production is complicated and the production efficiency is low. In addition, there is a problem in that since a defective work formed by processing must be discarded within a predetermined time from the start, material costs and wasted time are increased, and manufacturing costs are increased.

The present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is to provide a punch holder having a plurality of punch holders required for processing accuracy without stopping a transfer press. Only the punch holder in the process automatically corrects the bottom dead center position with respect to the bolster or the lower stand to the desired position, enabling stable molding from start-up. Simplified, low cost, and can be easily installed as an option on already delivered machines. It is an object of the present invention to provide a bottom dead center position correcting device for each process.

[0005]

In order to achieve the above object, the present invention provides an apparatus for correcting a bottom dead center position in each step of a transfer press. A bottom dead center position correcting device for a bolster of at least one punch holder required for processing accuracy among the punch holders, a slide block provided on the upper base so as to be movable up and down, and a driving means for moving the slide block And a punch holder provided on the slide block so as to be vertically adjustable, a sensor for detecting a bottom dead center position of the punch holder with respect to a bolster or a lower stand, and an actual bottom dead center position detected by the sensor is preset. The driving means so that the actual bottom dead center position approaches the reference bottom dead center position by comparing the reference bottom dead center position Those formed by providing a correction control means for controlling.

The driving means for moving the slide block includes:
An inclined guide groove engraved on the upper side of the slide block, and a gradient jib provided on the upper base so as to be movable in the horizontal direction and having an inclined guide portion on the lower side slidably engaged with the guide groove, It comprises a rotatable feed screw screwed into the female screw of the gradient jib, and a motor for rotating the feed screw.

[0007] Alternatively, the driving means for moving the slide block is provided with an inclined guide groove engraved on the upper side of the slide block and provided on the upper base so as to be movable in the horizontal direction and slidably engages with the guide groove. A gradient jib having a downwardly inclined guide portion on the lower side, a rotatable feed screw screwed with a female screw of the gradient jib, and a feed claw driven by an air cylinder member are fitted to the feed screw. It comprises a pawl feed mechanism that intermittently rotates the feed screw by engaging with the outer peripheral groove of the grooved wheel.

[0008]

According to the first and second aspects of the present invention, the same value as the sensor output value when the punch holder is at the desired bottom dead center position with respect to the bolster or the lower base is stored as a reference set value. The sensor detects the value of the actual bottom dead center position of the punch holder that changes due to thermal displacement, calculates a correction value from this actual value and the reference set value, controls the motor so that the actual value approaches the reference set value, and feeds it. The gradient jib is horizontally moved via a screw, and a slide block having an inclined guide groove which engages with an inclined guide portion is moved up or down, and is fixed to the punch holder so as to be movable up and down. The position of the bottom dead center of the punch holder is corrected.

A third aspect of the present invention compares the value of the actual bottom dead center position detected by the sensor with a reference set value stored in advance.
Drive the air cylinder, rotate the grooved wheel intermittently with the feed pawl one pitch at a time, rotate the feed screw, and move the slide block up or down so that the actual value approaches the reference set value. To correct the bottom dead center position of the punch holder.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. First Embodiment In a partial front view of a transfer press showing a bolster to which a die set is attached and a slide part of FIG. 1, a rectangular frame 1 erected on a floor has a bolster 1a integrally on a lower side. Vertical guides 2, 2 are formed inside the both side plate portions 1b, 1b. This guide 2,
A slide 3 is provided so as to be movable along 2 and the slide 3 is reciprocated a predetermined stroke by rotation of a crank or a cam (not shown). An upper die set 4A is provided on the lower surface of the slide 3, and a lower die set 4B is provided on the bolster 1a.
Is installed.

A die holder 6 is provided on the lower base 5 of the lower die set 4B, and a plurality of square-shaped punch holders 8 are mounted on the upper base 7 of the upper die set 4A so as to be vertically movable. . Most of the plurality of punch holders 8 are adjusted in the vertical direction by adjusting screws 9 shown in FIG. 4 which are screwed to the upper base 7 (that is, the punch holders 8 are attached to the dies (not shown) attached to the die holders 6). The predetermined position of the attached punch (not shown) is adjusted), and after the position adjustment is completed, the clamp lid 11 is crimped to restrict the movement with respect to the upper base. The description so far is not different from the prior art.

The transfer press is attached to a die holder 6 in each molding process, and a die (not shown)
The work is formed by a punch holder 8 in each forming process and a punch (not shown) attached to a punch holder 12 described later, and is sequentially transferred by a transfer device (not shown).

The bottom dead center position correction for each step of the present invention is performed only in the step in which the amount of change of the bottom dead center position due to the thermal displacement of the slide 3 with respect to the bolster 1a exceeds the allowable range of machining accuracy. For example, the seventh step corresponds to this, and performs the bottom dead center position correction of the punch holder 12 in the seventh step.

FIG. 2 shows this bottom dead center position correcting device.
7 is a sectional view taken along line AA of FIG.
Is attached to a slide block 13 which is movably engaged with the upper base 7 in the up-down direction, and is adjusted to a predetermined position in the up-down direction by an adjusting screw 14 screwed to the slide block 13, and the adjustment is completed. After that, the clamp lid 10 is screwed onto the slide block 13 and the punch holder 12 is crimped, so that the punch holder 1
2 is restricted.

The upper surface 13a of the slide block 13 is formed with a gradient, and a guide groove 13b shown in FIG. 4 is formed in parallel with the gradient. On the other hand, a horizontal guide groove 7a is formed in the upper base 7 directly above the slide block 13, and an upper guide portion 15a slidably engaged with the guide groove 7a and a gradient of the slide block 13 are provided. Guide groove 13b
And a lower guide part 15b slidably engaged with the inclined jib 15 is provided movably in the horizontal direction. A feed screw 17 screwed to a female screw engraved on the gradient jib 15 is horizontally and rotatably supported by the upper base 7, and a bevel gear 18 is keyed to the rear end of the feed screw 17. Have been.

A cross beam 21 is provided between both side plate portions 1b of the frame 1.
Is mounted, and a ball spline shaft 23 is rotatably supported by a cross beam 21 via a support 22. The ball spline shaft 23 is driven by a correction motor 20 whose rotation is controlled by a correction control system 30 described later.
Bevel gear 1 on the rear end face of slide 3 via bracket 24
9 is rotatably supported, and the female spline 2 is movably fitted to the bevel gear 19 on the ball spline shaft 23.
5, the bevel gear 19 is engaged with the bevel gear 18.

Further, a dog 26 is attached to the lower end of the slide block 13, and a sensor 28 is attached to the upper base 5 attached to the bolster 1 a via a support 27 so as to face upward. As the sensor 28, for example, a displacement sensor such as an eddy current type proximity sensor can be used. When the dog 26, which is the detection conductor, approaches by the vertical movement of the slide, a signal corresponding to the approach amount is output. The sensor 28 can be used as long as an output signal corresponding to the linear movement amount such as a magnescale or a linear scale can be obtained.

FIG. 3 is a block diagram showing a correction control system 3 for controlling the correction motor 23 based on the output signal of the sensor 28 to move the punch holder 13 up and down.
0. The maximum approach value storage unit 31 stores an output value of the sensor 28 when the punch holder 13 approaches the lower base 5 most. The comparing unit 32 compares the reference value stored in the reference set value storage unit 33 in advance with the maximum approach value. The correction amount calculation unit 34 calculates a correction amount by calculation. The motor drive unit 35 is a part that supplies drive power corresponding to the correction amount to the correction motor 20.

Next, the first operation of the embodiment will be described. First, a predetermined position in the vertical direction of the punch holder 12 with respect to the slide block 13 is adjusted with the adjusting screw 14, and the same value as the output signal of the sensor 28 when the punch holder 12 is at the desired bottom dead center position is set as a reference. The value is input to the reference set value storage unit 33 and stored. When the operation of the transfer press is started, initially, the output signal of the sensor 28 and the set value of the reference value storage unit 33 are the same value according to the above setting. No driving power is output from 35, and the molding process is performed without correction.

However, as time passes, the moving parts of the components of the transfer press gradually rise in temperature, and when the lower dead center positions of the slide 3, the upper table 7, and the punch holder 12 are displaced downward due to thermal expansion, the upper table 7 is displaced. , The bottom dead center of the punch holder 12 is also displaced downward by substantially the same amount, so that the sensor 28 detects this at a resolution of, for example, 0.01 mm. Then, the difference (correction amount) is obtained by comparing with the reference value,
The driving power corresponding to the correction amount is supplied from the motor driving unit 35 to rotate the correction motor.

The ball spline shaft 23 is rotated by the rotation of the correction motor 20, and the feed screw 17 is rotated via bevel gears 19 and 18. With the rotation of the feed screw 17, the gradient jib 15 is retracted to the right in FIGS.
The slide block 13 moves upward by an amount commensurate with the correction amount by the lower guide portion 15b and the guide groove 13b of the slide block 13. If the bottom dead center position of the slide 3 changes upward for some reason, the correction motor 20 is turned in the opposite direction to push the gradient jib 15 to the left, and the slide block 13 Move downward by an amount corresponding to.

The position of the bottom dead center of the punch holder 12 is appropriately corrected to the originally set desired position.
The position of the bottom dead center of the punch (not shown) attached to the punch holder 12 with respect to the die is kept constant, and the required processing accuracy can be satisfied.

Second Embodiment The difference from the first embodiment is only the driving means for rotating the feed screw 17 for moving the gradient jib 15, and the other parts are the same. Is omitted.
5 and 6, which show a side cross section of the drive means of the feed screw 17, a front view thereof, and FIGS. The grooved wheel 41 is keyed, and two swing arms 42A and 42B are swingably fitted to the outer periphery of the shaft of the grooved wheel 41 (FIG. 5).

Connecting joints 43A and 43B are rotatably connected to both ends of the swing arms 42A and 42B by pins 46 and 46, and are swingably supported on the rear end surface of the upper base 7 via support pieces 44. Two air cylinders 45A and 45B
Of the coupling rods 43A, 43B
(FIG. 6). Swing arm 42
Connecting joints 43A, 43 are attached to pins 46, 46 of A, 42B.
B and the feed claws 47A and 47B are rotatably supported (FIGS. 7 and 8). The feed claws 47A and 47B are springs 4
8, 48, the tip claw portion is urged to always contact the grooved wheel 41 (FIG. 7).

Further, a ball plunger 49 having a sphere engaged with the V-shaped groove 41a of the grooved wheel 41 is provided on the rear end surface of the upper base 7.
Is mounted, so that the grooved wheel 41 is rotated right or left by one pitch by one stroke of the air cylinder 45A or 45B. Therefore, when the grooved wheel 41 rotates by one pitch, the slide block 13 is, for example, 0.01 m.
m upward or downward, the correction control system 30
By making the air cylinder 45A or 45B make one reciprocation with the output signal, the bottom dead center position of 0.01 mm pitch can be corrected.

It should be noted that there is no problem even if hydraulic cylinders are used for the air cylinders 45A and 45B. The bottom dead center position correcting apparatus for each process of the present invention is not limited to only one process among a plurality of processes, but can be applied to all processes except the first process. In addition, the change of the bottom dead center position due to the thermal displacement of the slide 3 with respect to the bolster 1a from the start of the transfer press operation until the temperature reaches the saturation point is measured at regular intervals, and the bottom dead center position with respect to the measured time is measured. If the correction control system 30 stores the data of the displacement amount as a master table and reads out the displacement amount from the master table at regular time intervals and outputs a signal corresponding to the correction value, the position of the bottom dead center position which does not substantially hinder the operation can be obtained. A correction can be made, in which case the sensor 28 can be eliminated.

[0027]

Since the present invention is configured as described above, the following effects can be obtained. According to a first aspect of the present invention, at least one punch holder necessary for processing accuracy among a plurality of punch holders of a transfer press is mounted on a slide block movably engaged with an upper base so as to be able to adjust a vertical position, and a slide block is provided. The bottom dead center position is corrected based on the correction amount obtained from the actual bottom dead center position and the reference bottom dead center position stored in advance, so that the punch changes according to the thermal displacement without stopping the transfer press. The position of the bottom dead center of the holder can be automatically corrected, so that high-precision molding can be performed constantly and stably, and there is no need to stop and adjust the machine, thereby improving production efficiency. Further, since no defective work is discarded, material costs are reduced and wasted time is reduced, so that costs can be reduced.

According to a second aspect of the present invention, the driving means for moving the slide block is constituted by a simple mechanical structure provided around the upper base and a compensating motor, so that a small and inexpensive option which can be easily attached to a delivered machine is provided. Become.

In the third aspect, since the air cylinder drive is used instead of the motor drive, a bottom dead center position correction device which is resistant to electrical disturbances such as noise is provided.

[Brief description of the drawings]

FIG. 1 is a front view of a transfer press showing a bolster and a slide part to which a first die set according to an embodiment of the present invention is attached.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a configuration diagram showing a main part of FIG. 2 and a block diagram of a correction control system.

FIG. 4 is a sectional view taken along line BB of FIG. 2;

FIG. 5 is a cross-sectional view of a side surface for representing a second mainly air-cylinder type driving means.

FIG. 6 is a front view of the air cylinder type driving means.

FIG. 7 is a sectional view taken along line CC of FIG. 5;

FIG. 8 is a sectional view taken along line DD of FIG. 6;

FIG. 9 is an explanatory view of a conventional technique, and is a cross-sectional equivalent view taken along line EE of FIG. 1;

[Explanation of symbols]

Reference Signs List 1 frame 1a bolster 3 slide 4A upper die set 4B lower die set 7 upper stand 5 lower stand 8,12 punch holder 13 slide block 15 gradient jib 17 feed screw 20 correction motor 28 sensor 30 correction control system 41 grooved wheel 47A, 47
B Feed claw 45A, 45B Air cylinder

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-3-210999 (JP, A) JP-A-1-205900 (JP, A) JP-A-5-8099 (JP, A) JP-A-4- 91900 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B30B 13/00 B30B 15/06 B30B 15/14

Claims (3)

(57) [Claims] 1. A bottom dead center position correcting device for a bolster of at least one punch holder required for processing accuracy among punch holders for each process of an upper table fixed to a slide movable up and down of a transfer press, A slide block provided on the upper base so as to be movable up and down, a driving means for moving the slide block, a punch holder provided on the slide block so as to be vertically adjustable, and a bolster or a lower base of the punch holder. A sensor for detecting the bottom dead center position, and comparing the actual bottom dead center position detected by the sensor with a preset reference bottom dead center position, the actual bottom dead center position approaches the reference bottom dead center position. And a correction control means for controlling the driving means as described above. 2. A driving means for moving the slide block is provided with an inclined guide groove engraved on an upper side of the slide block, and is provided on the upper base so as to be movable in a horizontal direction and slidably engages with the guide groove. 2. A gradient jib having a lower inclined guide portion, a rotatable feed screw screwed with a female screw of the gradient jib, and a motor for rotating the feed screw. Bottom dead center position correction device for each transfer press process. 3. A driving means for moving the slide block is provided with an inclined guide groove engraved on the upper side of the slide block, and is slidably engaged with the guide groove provided on the upper base so as to be movable in a horizontal direction. A gradient jib having a downwardly inclined guide portion on the lower side, a rotatable feed screw screwed with a female screw of the gradient jib, and a feed claw driven by an air cylinder member are fitted to the feed screw. 2. The apparatus according to claim 1, further comprising a pawl feed mechanism for intermittently rotating said feed screw by engaging with an outer peripheral groove of the grooved wheel.