JP2001079619A - Device for controlling die position of press die - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a device for controlling a die position with a hydraulic cylinder in a press die controllable without using a hydraulic pump and with inexpensive constitution. SOLUTION: A spring 13 with which a punching die 2 is positioned in a punching position and also a piston 11 is upward energized by sucking in oil through the port part 14 of an oil chamber on the anti-rod side from an oil tank 18 is housed in the oil chamber on the anti-rod side of the hydraulic cylinder 10. In such a case, a relief valve 17 for making the oil escape from the oil chamber on the anti-rod side to the oil tank 18 when an oil pressure is increased than the oil pressure at the time of punching by downward pressing the punching die 2 with a bending edge part 4b at the time of bending and a check valve 15 for restraining the back flow of the oil from the oil chamber on the anti-rod side to the oil tank 18 and supplying the oil from the oil tank 18 when the spring 13 which is compressed with the piston 11 at the time of bending is returned in accordance with the ascent of a punching/bending die 4 are connected in series between the port part 14 and the oil tank 18.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blanking die having a cylindrical cutting die, a cutting blade descending from above toward the cutting die, and having a cutting blade portion and a bending blade portion having an increased outer diameter at the tip end. In order to perform drilling with a flange on a plate-like work with a press die equipped with a blade, so-called burring, a punching die is positioned at the drilling position by a hydraulic cylinder, and a relief that performs bending after drilling The present invention relates to a die position control device for a press die which is lowered to a position and returned to a drilling position following bending.

[0002]

2. Description of the Related Art In a die position control device of this type, a hydraulic pump controls the supply and discharge of oil to and from a hydraulic cylinder having a position sensor attached thereto by a hydraulic pump, so that a die for cutting is moved in accordance with the elevation of a bending blade. Are positioned at the drilling position and the lower relief position.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides an inexpensive die position control apparatus for a press die capable of controlling a hydraulic cylinder without using a hydraulic pump. With the goal.

[0004]

According to the present invention, there is provided a cylindrical die having a lower hole, which is guided up and down by a bending hole, and which has a hole. A plate-shaped workpiece is flanged by a press die that is lowered from above toward the punching die, and has a punching blade having a punching blade at the tip and a bending blade having a larger outer diameter above the punching blade. In order to perform the boring process, the punching die is positioned at the boring position by a hydraulic cylinder, then lowered to the relief position where bending is performed, and then returned to the boring position. In the position control device, the punching die is positioned at the drilling position in the oil chamber on the side opposite to the rod side of the hydraulic cylinder, and the oil is passed through the mouth of the oil chamber on the side opposite to the rod side from the oil tank. A spring that urges the piston upward so that it can be sucked is housed, and between the mouth and the oil tank, the punching die is pressed downward by the bending blade during bending, and the oil pressure is higher than the oil pressure when drilling. When it becomes larger, a relief valve that releases oil from the oil chamber on the opposite rod side to the oil tank, restrains the reverse flow of oil from the oil chamber on the opposite rod side to the oil tank, and the spring compressed by the piston during bending raises the bending blade. And a check valve for supplying oil from the oil tank when returning.

[0005] The spring urges the piston upward, and the oil is sucked into the oil chamber on the side opposite to the rod of the hydraulic cylinder through the check valve, whereby the punching die is supported at the drilling position. When the punching blade is lowered, the punching blade performs drilling, and the blade is further lowered to press the punching die downward, so that the oil pressure in the oil chamber on the non-rod side is drilled by the piston in conjunction with the punching. When the pressure is greater than the oil pressure of the oil tank, the relief valve releases the oil in the oil chamber on the opposite side to the oil tank. In the process of lowering the punching die to the relief position, bending is performed.

In order to limit the speed at which the punching die returns to the drilling position before the work is taken out after the completion of the flanged drilling, the bent work is transformed into a check valve according to the second aspect. To prevent this, a flow control valve for reducing the return speed of the punching die that returns from the relief position to the drilling position with the rise of the pulling / bending blade is connected in series. In order to prevent the compression of the oil in the oil chamber on the side opposite to the rod at the time of drilling, the oil tank is pressurized with air in order to reliably restrain the piston from retreating at the time of drilling.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A die position control apparatus for a press die for burring according to an embodiment of the present invention will be described with reference to FIGS. The pad 3 is supported via an elastic body 8 in the upper die 7 for drilling and bending by one stroke up and down, and is slidably inserted into the insertion hole 3a. Piercing blade 4a
And a bent blade portion 4b having an outer diameter stepwise increased above the bent blade portion 4b
Is provided below. Correspondingly, a cylindrical punching die 2 having a punching hole 2a is guided in the bending hole 1a of the lower die 1 so as to be able to move up and down. The punching dies are fixed to bases 19 attached to the distal ends of the rods 12 of the two hydraulic cylinders 10.

The oil chamber 10a on the side opposite to the rod of the hydraulic cylinder 10 accommodates a spring 13 for urging the piston 11 upward for positioning the punching die 2 at a drilling position and for sucking oil. I have. Hydraulic cylinder 1
Oil tank 18 and oil chamber 1 for supplying oil to oil tank 1
When the punching die 2 is pressed downward by the bending blade portion 4b between the mouth portions 14a of the oil tank 10a, and the oil pressure in the oil chamber 10a becomes larger than the oil pressure at the time of drilling by the pressurization by the piston 11, the oil is removed from the oil tank 18a. Relief valve 1
7, a check valve 15 for restricting the backflow of oil to the oil tank 18, and a flow control valve 16 in series with the check valve are connected in parallel.

The flow control valve 16 is provided with a check valve 15 so as to reduce the return speed of returning from the relief position to the drilling position by the return of the spring 13 compressed by the punching die 2 with the rise of the bending blade portion 4b. , The flow rate of the oil supplied to the oil tank 18 is reduced. The amount of drawing is set so that the bent work 9 is not deformed by the contact of the punching dies 2 particularly when the pad 3 is not separated from the work 9.

The operation of the thus-configured die position control device will be described with reference to FIG. As shown in FIGS. 1 and 2A, the punching die 2 is filled with oil in the oil chamber 10a by the urging of the piston 11 of the spring 13 and occupies a drilling position in a normal state. The upper end surface of the punching die 2 is substantially flush with the upper peripheral surface of the bending hole 1 a of the lower die 1. With the work 9 set on the lower die 1, the pad 3 is lowered so as to contact the work 9. Then, as the drawing / bending blade 4 further descends through the insertion hole 3a, as shown in FIG. B, a punching process corresponding to the inner diameter of the punching die 2 is performed by the punching blade portion 4a of the drawing / bending blade 4.

During this time, the check valve 15 restricts the reverse flow of the oil in the oil chamber 10a, and the relief valve 17 remains closed because the oil pressure does not reach the operating pressure at the time of drilling. Next, as shown in FIG. 7C, when the extraction / bending blade 4 attempts to descend to the bottom dead center, the oil pressure increases, the relief valve 17 opens, the oil returns to the oil tank 18, and the extraction die 2 The spring 13 is compressed and descends in conjunction with the relief position, and in this process, the bending blade portion 4b is bent into the bending hole 1a.
And a bending process is performed to form a flange portion.

Subsequently, as shown in FIG.
Rises toward the original position, oil is sucked from the oil tank 18 into the oil chamber 10a via the check valve 15 and the flow control valve 16 with the return of the spring 13, and at this time, the oil is The inflow speed is reduced, the return of the spring 13 is restricted, and the work 9 already processed by the punching die 2 is removed.
Is avoided.

Another embodiment is to prevent the oil chamber 10a from becoming slightly negative due to expansion of air or piping contained in oil even when the relief valve 17 is not operated during drilling. Alternatively, it is conceivable to seal the oil tank 18 and pressurize the oil with, for example, factory air of 5 kgf / cm ² .

[0014]

According to the first aspect of the invention, the position control between the drilling position and the relief position of the punching die by the hydraulic cylinder is performed with a simple and inexpensive configuration without a hydraulic pump. According to the second aspect of the present invention, it is possible to prevent the processed workpiece from being damaged by the punching die that returns before the workpiece is taken out. According to the third aspect of the present invention, sinking of the punching die during drilling is reliably prevented, and the quality of burring can be maintained at a high level.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a die position control device for a press die according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating the operation of the dice position control device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lower die 1a Bending hole 2 Die 2a Drilling hole 3 Pad 3a Guide hole 4 Bending blade 4a Bending blade 4b Bending blade 7 Upper die 10 Hydraulic cylinder 10a Oil chamber 11 Piston 12 Rod 15 Check valve 16 Flow control valve 17 Relief valve 18 Oil tank

Claims (3)

[Claims] 1. A lower die is guided to be able to ascend and descend in a bending hole,
A cylindrical punching die having a punching hole, and a punching blade that descends from above toward the punching die, and has a punching blade portion at a tip portion and a bending blade portion having an outer diameter increased above the punching blade portion. In order to perform drilling with a flange on a plate-shaped work with a press die provided, the punching dies are positioned at the drilling position by a hydraulic cylinder, then lowered to the relief position where bending is performed, and then the drilling position In the die position control device of the press die, the punching die is positioned at the drilling position in the oil chamber on the side opposite to the rod of the hydraulic cylinder, and the opening of the oil chamber on the side opposite to the rod is located from the oil tank. A spring for urging the piston upward so that oil is sucked through the opening portion, between the mouth portion and the oil tank, a bending blade during bending. The relief die releases the oil from the non-rod side oil chamber to the oil tank when the extracting die is pressed downward and the oil pressure becomes larger than the oil pressure at the time of drilling. The check valve that supplies oil from the oil tank when the spring compressed by the piston returns during the bending process with the rise of the extraction blade is restrained, and a check valve that supplies oil from the oil tank during the bending process is provided in parallel. A die position control device for a press die, being connected. 2. A non-return valve is provided with a flow control valve for reducing a return speed of a punching die which returns from a relief position to a drilling position with a rise of a drawing / bending blade so that a bent workpiece is not deformed. The die position control device for a press die according to claim 1, wherein the die position control device is connected in series. 3. The die position control device for a press die according to claim 1, wherein the oil tank is pressurized with air so as to restrain the piston from retreating during drilling.