JPH0724959B2 - Breakthrough countermeasure device for press machine - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a breakthrough countermeasure device that occurs when punching is performed by a press machine, and more particularly to a device that can also perform a slide adjusting operation and a bottom dead center correcting operation.

[0002]

BACKGROUND ART A slide connected to an eccentric part of a crankshaft via a connecting rod is moved up and down by rotation of the crankshaft,
When punching a material with the upper die attached to the slide and the lower die attached to the bolster, even if the upper die comes into contact with the material, the material is not punched immediately due to the resistance of the material, and the reaction force from the material As a result, an upward compressive force acts on the slide, connecting rod, etc., and an extension load acts on the column connecting the bed and crown of the press machine, and elastic energy due to extension deformation is accumulated on this column. The accumulated elastic energy is released at the same time as the punching of the material is completed, and a large vibration and noise are generated in the press machine due to the breakthrough due to the rapid lowering of the upper die. Conventionally, as a countermeasure against such breakthrough, a press machine is installed on the floor via an elastic body such as a pneumatic spring and the impact at the time of punching is absorbed by this elastic body, or between the slide and the bolster or above. A hydraulic shock absorber is arranged between the mold and the lower mold to reduce the slide after punching and the rapid lowering of the upper mold by the hydraulic shock absorber.

[0003]

The above-mentioned conventional breakthrough countermeasure device is a passive device which operates after the upper die punches out the material, and is a passive device, and the solution of vibration and noise due to breakthrough is solved. It was not always a sufficient means. In addition, the conventional breakthrough countermeasure device is for solving the problem of only breakthrough, and it can be performed by slide adjusting work or press working heat when the height dimension of the upper mold and the lower mold is changed by changing the mold. In order to perform bottom dead center correction work when the bottom dead center of the slide changes due to thermal expansion deformation of the slide etc., a device that can perform these works must be provided in the press machine separately from the breakthrough countermeasure device. There wasn't.

The object of the present invention is to enable effective operation before the completion of punching of material to positively solve the problems of vibration and noise due to breakthrough, and also to perform slide adjustment work and bottom dead center correction work. There is a breakthrough countermeasure device for a press machine.

[0005]

In a breakthrough countermeasure device for a press machine according to the present invention, a hydraulic cylinder is mounted at an upper end of a slide between a connecting rod whose upper portion is rotatably fitted to an eccentric portion of a crankshaft and a slide. The internal chamber of this hydraulic cylinder is divided into an upper chamber and a lower chamber by the piston part of the pressure receiving member that can move up and down, and the connecting rod is connected to the upper part protruding from the hydraulic cylinder of the pressure receiving member. , The first hydraulic circuit can supply high pressure hydraulic oil to the lower chamber and the second hydraulic circuit can supply low pressure hydraulic oil to the upper chamber,
A connection circuit that connects the upper chamber and the lower chamber is provided between the first and second hydraulic circuits, and a switching valve that is turned on and off to open and close the connection circuit is arranged in the connection circuit. A throttle valve is provided in at least one of the first and second hydraulic circuits and the connection circuit on the downstream side of the connection point, and the slide height position can be detected by a slide height position detection sensor, When the height of the slide reaches the position just before punching of the material, the switching valve is turned on by the signal from the sensor to open the connection circuit.

[0006]

When the low pressure oil is supplied to the upper chamber by the second hydraulic circuit and the high pressure oil is supplied to the lower chamber by the first hydraulic circuit, the pressure receiving member rises with respect to the hydraulic cylinder to keep the pressure receiving member at a predetermined level. Raise to the height position. After that, when the switching valve is turned on to open the connection circuit, the high pressure oil in the lower chamber flows into the upper chamber, and the pressure receiving member descends with respect to the hydraulic cylinder, so that the slide height position with respect to the connecting rod is changed. Change.
As a result, the slide adjustment work and the bottom dead center correction work can be performed. Material is punched by the upper die attached to the slide and the lower die attached to the bolster, so when the height of the descended slide reaches the position just before punching, switching is performed based on the signal from the slide height position detection sensor. The valve is turned on, whereby the connection circuit is opened and the compressed pressure oil in the lower chamber flows into the upper chamber while being throttled by the throttle valve. At this time, the elastic energy accumulated in the column of the press machine is converted into the flow velocity energy of the pressure oil, and is also converted into heat energy by the throttle valve, which is converted into heat energy and released outside the press machine.

[0007]

An embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows a press machine 1 equipped with an apparatus according to this embodiment. A motor 3 is arranged on the crown 2 of the press machine 1, and the driving force of the motor 3 is transmitted to a crankshaft 8 with a brake 7 via a belt 4, a flywheel 5 and a clutch 6. An eccentric portion 8A is provided on the crankshaft 8, an upper portion of a connecting rod 9 is rotatably fitted to the eccentric portion 8A, and a slide 11 is connected to a lower portion of the connecting rod 9 via a breakthrough countermeasure device 10. .
When the crank shaft 8 is rotated by the motor 3, the slide 11 moves up and down while being guided by the slide guide 14 provided on the column 13 that connects the bed 12 and the crown 2.
The material 19 supplied by the feed roller device 18 is composed of the upper die 15 which is a punch attached to the slide 11 and the lower die 17 which is a die attached to the bolster 16.
Is punched.

A slide height position detecting sensor 20 is arranged on the column 13, and the height position of the slide 11 is constantly detected by the sensor 20.
The electric signal from is input to a control device (not shown).

FIG. 2 shows a breakthrough countermeasure device 10. This breakthrough countermeasure device 10 has a slide 11
The hydraulic cylinder 21 is fixed to the upper end of the hydraulic cylinder 21 and is arranged between the connecting rod 9 and the slide 11, and a vertically movable pressure receiving member 22 that receives the hydraulic pressure in the hydraulic cylinder 21. A lower portion of the pressure receiving member 22 is a piston portion 23, and the piston portion 23 divides the internal chamber of the hydraulic cylinder 21 into an upper chamber 24 and a lower chamber 25. The piston portion 23 has an upper large diameter portion 23A and a lower small diameter portion 23B.
The upper chamber 24 in which the large diameter portion 23A moves up and down has a large area, and the lower chamber 25 in which the small diameter portion 23B moves up and down has a small area. An upper portion 22A of the pressure receiving member 22 projects upward from the hydraulic cylinder 21, and a lower portion of the connecting rod 9 is connected to the upper portion 22A by a wrist pin 26.

A first hydraulic circuit 28 extending from the hydraulic source 27 is connected to the lower chamber 25, and a second hydraulic circuit 29 extending from the hydraulic source 27 is connected to the upper chamber 24. The first hydraulic circuit 28 is provided with a first switching valve 30 and a first variable throttle valve 31 from the upstream side, and the second hydraulic circuit 29 is provided with a pressure reducing valve 32 and a second variable throttle valve 33 from the upstream side. There is. A connection circuit 34 is provided between the first and second hydraulic circuits 28 and 29, the lower chamber 25 and the upper chamber 24 are connected by this connection circuit 34, and a second switching valve 35 is provided in the connection circuit 34. There is. The positions of the first and second variable throttle valves 31 and 33 in the first and second hydraulic circuits 28 and 29 are located downstream of the connection point with the connection circuit 34.

The first and second switching valves 30 and 35 open and close the circuits 28 and 34 by operating on and off, and the on and off operations of these valves 30 and 35 are performed automatically or manually. The operation of the second switching valve 35 is performed based on an electric signal relating to the height position of the slide 11 from the slide height position detection sensor 20 input to the control device. There is. At least the second switching valve 35 of the first and second switching valves 30 and 35 is a highly responsive valve in which the ON / OFF switching operation is performed at an extremely high speed, and the ON / OFF operation is performed many times in a short time. Can be switched.

In order to supply the pressure oil from the hydraulic pressure source 27 to the hydraulic cylinder 21, the following steps are performed. After the first and second switching valves 30 and 35 are turned off to close the first hydraulic circuit 28 and the connection circuit 34, when high pressure hydraulic oil is sent from the hydraulic pressure source 27, the pressure oil is predetermined by the pressure reducing valve 32. After being reduced to a pressure, it is supplied to the upper chamber 24 via the second hydraulic circuit 29,
The pressure receiving member 22 is lowered by hydraulic pressure to the lower limit. Next, when the first switching valve 30 is turned on to open the first hydraulic circuit 28, the high pressure oil from the hydraulic source 27 is sent to the lower chamber 25 via the first hydraulic circuit 28. Since the pressure of the pressure oil supplied to the lower chamber 25 is not reduced by the pressure reducing valve 32, even if the area of the lower chamber 25 is smaller than that of the upper chamber 24, the pressure receiving member 22 is raised by the hydraulic pressure in the lower chamber 25. To do. The pressure oil pushed out from the upper chamber 24 is transferred from the pressure reducing valve 32 to the tank 36.
Return to. After the pressure receiving member 22 has risen to a predetermined height with respect to the hydraulic cylinder 21, the first switching valve 30 is turned off to close the first hydraulic circuit 28. As a result, the upper chamber 24 is filled with low pressure oil, and the lower chamber 25 is filled with high pressure oil.

Thereafter, when the second switching valve 35 is turned on to open the connection circuit 34, the high pressure oil in the lower chamber 25 flows into the upper chamber 24 through the connection circuit 34, and the pressure receiving member 22 is hydraulically operated. It descends with respect to the cylinder 21. When the second switching valve 35, which is a highly responsive valve, is switched on and off a large number of times, a large amount of pressure oil flows into the upper chamber 24, so that the pressure receiving member 22 descends by a large stroke.
The amount of lowering of the pressure receiving member 22 can be determined by the number of times the switching valve 35 is switched on and off.

As a result, the slide 11 changes its height position with respect to the connecting rod 9, and therefore,
A slide adjusting operation for determining the height position of the slide 11 according to the height dimension of the upper mold 15 and the lower mold 17 at the time of exchanging the mold, and the slide 11 and the like are thermally expanded and deformed by the heat of press working, and the slide 11 is When the bottom dead center changes, the bottom dead center correction work can be performed.

Next, the operation of the breakthrough countermeasure device 10 when punching the material 19 by moving the slide 11 up and down will be described. Even if the slide 11 descends and the upper mold 15 comes into contact with the material 19, the material 19 remains
It is not immediately punched out by the resistance force of 9, and the upward compression force acts on the slide 11, the connecting rod 9, etc. by the reaction force from the material 19, and the column 13 shown in FIG. Elastic energy of extensional deformation is accumulated. When the rotation of the crankshaft 8 progresses and the slide 11 reaches a height position just before punching out the material 19, this height position is detected by the slide height position detection sensor 20, and the above-mentioned control is performed based on an electric signal from the sensor 20. The device activates the second switching valve 35 and sends a signal to open the connection circuit 34. At this time, since the pressure of the pressure oil in the lower chamber 25 is high due to the downward pressing force of the pressure receiving member 22, when the second switching valve 35 is turned on, the lower chamber 25 is turned on.
The pressure oil inside passes through the connection circuit 34 and flows into the upper chamber 24 while the flow rate is throttled by the first and second variable throttle valves 31, 33,
The pressure receiving member 22 descends with respect to the hydraulic cylinder 21.

As a result, the elastic energy accumulated in the column 13 is converted into the flow velocity energy of the pressure oil pushed out from the lower chamber 25 to the upper chamber 24 by the pressure receiving member 22, and the first and second variable throttle valves 31, It is converted into heat energy at 33. Therefore, when the upper die 15 punches out the material 19, the elastic energy accumulated in the column 13 is rapidly lowered by the slide 11 and the upper die 15 to cause the press machine 1 to move.
The large amount of vibration and the generated energy of noise are not generated, and this elastic energy is released from the first and second variable throttle valves 31 and 33 as heat energy to the outside of the press machine 1,
The breakthrough of the press machine 1 during punching is reduced.

Simultaneously with or slightly after the completion of punching, the second switching valve 35 is turned off and the first switching valve 30 is turned on, so that a high hydraulic pressure from the hydraulic pressure source 27 flows through the first hydraulic circuit 28. Through the lower chamber 25, the pressure receiving member 22 that has been lowered is raised, and the breakthrough countermeasure device 10 is returned to the old state. Then, the first switching valve 30 is turned off, thereby returning to the state for performing the next punching process.

In the embodiment described above, the throttle valve 31,
Although 33 is provided in both hydraulic circuits 28 and 29 on the downstream side of the connection point with the connection circuit 34, the throttle valve may be provided in only one of these hydraulic circuits 28 and 29. Further, it may be provided in the connection circuit 34. Further, in the above-described embodiment, the connecting rod 9 and the pressure receiving member 22 of the breakthrough countermeasure device 10 are connected by the wrist pin 26, but these connections may be made by a connecting member having a spherical contact ball portion. The device according to the present invention can be applied not only to a press machine in which one slide is connected to a crankshaft via one connecting rod, but also to a press machine in which two slides are connected to each other via two or more connecting rods.

[0019]

Since the break-through countermeasure device according to the present invention operates before the completion of punching of the material, the problems of vibration and noise due to break-through can be positively solved, and the slide adjusting work and the bottom dead center correction work can be performed. Because you can
There is no need to attach special equipment to the press machine to perform these tasks.

[Brief description of drawings]

FIG. 1 is an overall front view of a press machine equipped with an apparatus according to an embodiment of the present invention.

FIG. 2 is a partial cross-sectional front view showing the breakthrough countermeasure device shown in FIG. 1, including a hydraulic circuit.

[Explanation of symbols]

 1 Press machine 8 Crankshaft 8A Eccentric part 9 Connecting rod 10 Breakthrough countermeasure device 11 Slide 15 Upper mold 17 Lower mold 19 Material 20 Slide height position detection sensor 21 Hydraulic cylinder 22 Pressure receiving member 23 Piston part 24 Upper chamber 25 Lower chamber 28th 1 hydraulic circuit 29 second hydraulic circuit 30, 35 switching valve 31, 33 throttle valve 34 connection circuit

Claims (1)

[Claims] 1. A hydraulic cylinder fixed between the slide and a connecting rod, the upper part of which is rotatably fitted to the eccentric part of the crankshaft, and fixed to the upper end of the slide, and an internal chamber of the hydraulic cylinder. Has a piston portion that divides the upper chamber into a lower chamber, and an upper portion protruding from the hydraulic cylinder is connected to a lower portion of the connecting rod, and is vertically movable, and supplies high-pressure pressure oil to the lower chamber. A first hydraulic circuit,
A second hydraulic circuit for supplying low pressure oil to the upper chamber, a connection circuit provided between the first and second hydraulic circuits for connecting the upper chamber and the lower chamber, and a connection circuit in the connection circuit. A switching valve that is provided to open and close the connection circuit, and is provided in at least one of the first and second hydraulic circuits and the connection circuit downstream of the connection point with the connection circuit. A slide height position for detecting the throttle valve and the height position of the slide, and turning on the switching valve to open the connection circuit when the height position of the slide reaches the position just before the punching of the material. A breakthrough countermeasure device for a press machine, which is configured to include a detection sensor.