JPH049113Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a hydraulic press with a vibration function.

[Prior Art] A so-called hydraulic press is known in which a cylinder device is disposed in the upper part of a press body, a slide is supported by a piston of the cylinder device, and press processing is performed by applying high-pressure oil pressure to the cylinder device.

Even in such hydraulic presses, lubricating oil is used during press processing to deal with thermal problems and the like.

[Problems to be Solved by the Invention] However, when a mirror finish or a high precision finish is required, there is a problem in that variations in the lubricating oil film cause roughness on the product surface, making it impossible to achieve a desired finish.

On the other hand, a press machine has been proposed that applies vibration energy to a synthetic resin plate or the like to make small holes.
This method converts vibrational energy into heat to melt the resin while drilling holes.

Therefore, the applicant first repeated experiments to see if it was possible to eliminate variations in the lubricating oil film by applying vibration to the mold, but although it was found to be effective in the laboratory, it was not possible to compression mold large precision parts. Hydraulic presses that can perform such operations have not been put into practical use mainly due to the difficulty of reversibly operating the cylinder device and the fact that the entire press body becomes extremely large.

The present invention has been devised in view of the above circumstances, and its purpose is to provide a hydraulic press that is compact in its entirety and has a vibration function with high responsiveness.

[Means for Solving the Problems] The present invention has a large cylinder device that applies press pressure to the upper die, which is disposed on the upper part of the press body, and which separates the upper die from the lower die by resisting the press pressure. A plurality of small cylinder devices are arranged at the bottom of the press body facing the large cylinder device, and a pressure regulating valve is installed to adjust the hydraulic pressure applied to the large cylinder device to a predetermined value in order to maintain the press pressure constant. a supply valve that applies hydraulic pressure to simultaneously operate each small cylinder device; and a discharge valve that releases hydraulic pressure in the small cylinder device to simultaneously deactivate each small cylinder device; A control device is provided to alternately open and close the supply valve and the discharge valve in each switchable cycle while operating the press pressure to be kept constant, and is configured to perform press working while vibrating the upper mold. , to achieve the above objectives.

[Function] According to the present invention having such a configuration, a plurality of small cylinder devices are arranged to face a large cylinder device that applies press pressure, and the pressure regulating valve is controlled by a control device to maintain the press pressure at a constant level. Since the supply valve and the discharge valve are alternately switched while operating as shown in FIG.

Thereby, by appropriately selecting the vibration cycle depending on the material of the material and the pressing mode, it is possible to achieve a mirror finish or the like while vibrating the upper die.

[Example] An example of a hydraulic press equipped with a vibration function according to the present invention will be described in detail based on the drawings.

In the figure, a press body 1, a large cylinder device 10, a driving oil system 20 including a pressure regulating valve 23, a plurality of small cylinder devices 30, a supply valve 35, and a discharge valve 4 are shown.
5 and a control device 50 constitute a hydraulic press.

The large cylinder device 10 is arranged at the upper part of the press main body 1, and the plurality of small cylinder devices 30 are arranged at the lower part of the press main body 1. This results in
The large cylinder device 10 can share the forward movement (pressing operation) and the backward movement (release operation) between the large cylinder device 10 and the small cylinder device 30 without forcing one large cylinder device 10 to perform reversible vertical movement. Not excessive. In addition, each small cylinder device 30 can be immediately reciprocated by switching the supply valve 35 and the discharge valve 45 simultaneously by the control device 50, so that quick response can be improved.

The main components are explained below.

First, a hydraulic press is composed of a press body 1 made of a highly rigid frame, columns 3 erected at the four corners of this press body 1, and slides 4 slidingly guided by each column 3. The mold 8 is attached to the slide 4, and the lower mold 9 is placed and fixed on the bottom of the press body 1. Slide 4 is large cylinder device 1
0 for forward movement (downward in the figure) and backward movement (upward in the figure) by the plurality of small cylinder devices 30. still,
7 is a position detector for detecting the vertical position of the slide 4.

Each column 3 is formed to serve as a guide post for the slide 4 and a tie rod for the press body 1 (more specifically, it has an upper and lower split frame structure).

The large cylinder device 10 consists of a cylinder 11 supported on the upper part of the press body 1 and a piston 13, and a slide 4 is fixed to the piston 13. The piston 13 is provided with a round hole 14 that opens at the top, while a through hole 12 is provided in the top of the cylinder 11. An oil guide pipe 15 is attached to the round hole 14 and the through hole 12. This large cylinder device 10 is moved forward by a driving oil system 20.

The driving oil system 20 is formed from a press oil passage 21 that connects a hydraulic pressure source 27 and the cylinder 11, and a flow rate adjustment valve 22 and a pressure adjustment valve 23 provided in this press oil passage 21. 24 is a pressure detector.

Therefore, press pressure can be applied to the slide 4 by supplying driving oil into the oil guide pipe 15 to move the slide 4 forward (downward) under no load, and by supplying driving oil into the cylinder 11. .

Note that the driving oil pressure in the cylinder 11 is always kept constant except in transient cases by a pressure regulating valve 23 controlled by a control device 50, which will be described in detail later. However, the absolute value of the pressure can be switched and selected by the pressure detector 24, a controller 53A (described later), a drive circuit 54, a control unit 51, etc.

On the other hand, the small cylinder device 30 consists of four units arranged at the lower four corners of the press body 1 as described above, and each cylinder device 30 is formed from a cylinder 31 and a piston 32 fixed to the press body 1. There is. The piston 32 is provided with four cylindrical parts 33 that slidably pass through four parallel through holes 2 provided in the press body 1, and is fixed to the lower surface of the slide 4 via these cylindrical parts 33. ing. Each small cylinder device 30 is moved back (raised) by the cooperation of the supply valve 35, the discharge valve 45, and the like.

Providing the small cylinder device 30 at the bottom also has the function of reducing the amplitude to zero when the press body (frame) 1 vibrates.

In other words, if reciprocating motion (vibration) is generated only by the large cylinder device at the top, tensile force will be applied during forward motion (pressing), causing backward motion (return).
There will be no load. In other words, the entire press body 1 deforms in the vertical direction in the figure, making it impossible to obtain an accurate position.
Moreover, the stress and amplitude applied to the press body 1 become extremely large.

However, if the small cylinder device 30 is disposed at the bottom, the material (product) W will receive force when the press body 1 moves back and forth, and the small cylinder device 30 will receive that force during the return movement. 1 as a whole, it will receive an almost constant force. That is, although a certain stress continues to be generated in the press body 1 during vibration, its amplitude becomes almost zero, and the deformation due to the stress is also constant. Therefore, not only can the position of the slide 4 including the bottom dead center be detected accurately without error, but also the fatigue strength of the press body 1 can be improved.

The supply valve 35 is an automatic opening/closing valve, and is provided in a supply oil path 36 that connects each small cylinder device 30 and the hydraulic pressure source 27. On the upstream side of this supply valve 35 is a pressure regulating valve 37 similar to the pressure regulating valve 22.
is provided. 38 is a pressure detector, and 39 is a relief valve.

Therefore, when the supply valve 35 is opened, oil of the same pressure is supplied to each cylinder 31 at the same time, and the slider 4
can be reversed. In this case, the pressure inside the cylinder 11 of the large cylinder device 10 is maintained constant by the function of the pressure regulating valve 23. If the discharge valve 45 is opened at this time, the oil pressure in each cylinder 31 is reduced, and as a result, the slide 4 moves forward again due to the constant pressure in the cylinder 11. The discharged oil from the discharge valve 45 may be returned to a separate tank or the like, but in this embodiment, it is connected to the press oil passage 21 via a discharge oil passage 46. small cylinder 3
This is to supply the high pressure inside the large cylinder 11 to the large cylinder 11 and use it effectively for quick forward movement of the slide 4.

Therefore, a check valve 47 is provided in the discharge oil passage 46 so that it does not operate all the time.

Next, a control device 5 is provided to apply press pressure while vibrating the slide 4 (upper mold 8) by switching the large cylinder device 10 and each small cylinder 30.
0 is composed of a control unit 51, a setting device 52, controllers 53A to 53C, and drive circuits 54A to 54D.

The setting device 52 is formed from a digital switch or the like, and is used to set the frequency of vibration per unit time, press pressure, etc.

The control unit 51 is formed from a CPU, and controls each controller 53A to 53C based on the setting value of the setting device 52 and the program stored in the built-in ROM.
A predetermined signal is output at a predetermined timing.

The timing at which the upper die 8 starts vibrating is conditioned on the output signal PST of the position detector 7. This is to eliminate unnecessary vibration near the top dead center of the slide 4 and to allow the vibration function to be exhibited when it is useful.

The controller 53A drives and controls the pressure regulating valve 23 via the drive circuit 54A, and feeds back the detection signal of the pressure detector 24 to keep the oil pressure in the press oil passage 21 constant. The target value of the oil pressure is input from the control unit 51. In this embodiment, since the pressure regulating valve 23 is driven by a pulse motor, the drive circuit 24 outputs a pulse signal.

Further, the controller 53B drives and controls the flow rate regulating valve 22 via the drive circuit 54B.
The flow rate adjustment valve 22 is also driven by a pulse motor.

Therefore, the flow rate regulating valve 22 and the pressure regulating valve 23
By controlling the drive according to a predetermined program of the control unit 51, the large cylinder device 10 is driven and the slide 4 (upper die 8) can be moved forward in a predetermined mode.

The controller 53C drives and controls the pressure regulating valve 37 via the drive circuit 54C. Supply oil path 36
The oil pressure inside the pump is maintained at the target value by feedback from the pressure sensor 38. The pressure regulating valve 37, like the pressure regulating valve 23, is driven by a pulse motor.

Next, the drive circuit 54D switches the supply valve 35 and the discharge valve 45 every predetermined cycle, and the switching timing is determined by the control unit 51 forming the control device 50 (based on the set value of the setting device 52).
Regulated by output signal. The early or late switching timing determines the vibration cycle of the upper mold 8. Note that the stroke of the upper die 8 is determined by the flow rate regulating valve 22.

Here, each small cylinder device 30 is operated simultaneously, and the slide 4 resists the own weight of the piston 13, the slide 4, the upper die 8, and the hydraulic pressure in the cylinder 11.
It has the ability to rise or return.

Next, the effect will be explained.

The frequency (for example, 100 HZ) and vibration amplitude (stroke) are set on the setting device 52.

Here, considering the case where the slide 4 is moved from the top dead center to the bottom dead center as shown in the figure, the drive circuit 54D closes the supply valve 35 and closes the discharge valve based on the command from the control unit 51. 45 have been established.

On the other hand, the pressure regulating valve 23 and the flow regulating valve 22 are drive-controlled by drive circuits 54A and 54B.

That is, the large cylinder device 10 first moves the slide 4 forward using hydraulic pressure supplied from the oil guide pipe 15 into the round hole 14 . When the upper mold 8 approaches or comes into contact with the material W placed on the lower mold 9, a predetermined hydraulic pressure is applied in the cylinder 11 to press it.

In this state, the output signal of the position detector 7 is
Based on PST, a switching signal is output from control unit 51 to drive circuit 54D. Prior to this, the pressure regulating valve 37 is operated to establish a predetermined pressure.

Therefore, when the supply valve 35 is opened and the discharge valve 45 is closed, each small cylinder device 30 operates simultaneously, and the slide 4 is pushed up from the lower side. Slide 4 moves back (raises). In this case, cylinder 11
The hydraulic pressure inside is kept constant by the function of the pressure regulating valve 23.

Subsequently, when the slide 4 moves back by a predetermined stroke, the control unit 51 outputs a switching signal to the drive circuit 54D again, and the supply valve 35 is closed and the discharge valve 45 is opened. The hydraulic pressure inside the cylinder 31 of the small cylinder device 30 is controlled by the discharge valve 45 and the check valve 4.
7. The oil is returned to the press oil path 21 through the discharge oil path 46. This is to effectively utilize the high pressure for forward movement of the slide 4. Of course, the flow rate regulating valve 22 and the pressure regulating valve 23 operate, and the slide 4 is moved forward again.

Therefore, the drive circuit 54A operates the pressure regulating valve 23 to maintain the press pressure constant, and the drive circuit 54D switches between the supply valve 35 and the discharge valve 45, thereby causing the press to vibrate in a predetermined cycle. Can be processed.

Note that during press working, the press pressure can be gradually increased according to the reaction force that increases the deformation resistance of the material (product) W. The above of the control unit 51
By programming it in ROM.

However, according to this embodiment, since the large cylinder device 10 and the plurality of small cylinder devices 30 are vertically arranged opposite each other, problems arise when the large cylinder device 10 is provided with forward and backward movement functions. It is possible to establish a small practical hydraulic press with a vibration function, which overcomes the disadvantages of the large cylinder device 10 being extremely large and having a small diameter at the connecting portion with the slide 4, making it vulnerable to eccentric loads.

Also, a large cylinder device 10 that applies press pressure
At the top of the press body 1, each small cylinder device 3
0 is provided at the bottom, and the pressure inside the cylinder 11 of the large cylinder device 10 is kept constant, so it has high responsiveness and can generate vibrations of, for example, about 200 HZ. can be added.

Furthermore, since the small cylinder device 30 is disposed at the bottom, the amplitude of the press body 1 can be small and deformation due to stress can be kept constant.

Furthermore, the structure is such that vibration is applied to the slide 4 by switching between the supply valve 35 and the discharge valve 45, and switching between both 35 and 45 is performed based on electrical commands from the setting device 52, control unit 51, etc. A predetermined cycle, stroke, etc. can be easily selected and set in light of the material and finishing condition of the material. According to experiments, it was possible to compression mold copper and aluminum products with a mirror finish.

Furthermore, since the discharged oil from the discharge valve 45 is returned to the press oil passage 21 so that its high pressure can be utilized, it is useful for speeding up the operation of the large cylinder device 10, and is also useful for speeding up the operation of the large cylinder device 10. It is not necessary and is advantageous in terms of equipment economy.

[Effects of the invention] As explained above, the present invention has a large cylinder device placed in the upper part of the press body and a plurality of small cylinder devices placed oppositely in the lower part of the press body, and valves can be switched while maintaining the press pressure constant. Since the configuration is such that vibration is generated by switching the small cylinder device, it is possible to provide a hydraulic press with a vibration function that is highly responsive, compact, and low cost.

[Brief explanation of drawings]

The figure is an overall configuration diagram showing an embodiment of the present invention. 1...Press body, 8...Upper die, 9...Lower die,
10... Large cylinder device, 30... Small cylinder device, 35... Supply valve, 45... Discharge valve, 50
……Control device.

Claims (1)

[Claims for Utility Model Registration] A large cylinder device that applies press pressure to the upper mold is disposed at the top of the press body, and a plurality of small cylinder devices that resist the press pressure and separate the upper mold from the lower mold. is placed at the bottom of the press body facing the large cylinder device, and a pressure regulating valve is installed to adjust the hydraulic pressure applied to the large cylinder device to a predetermined value in order to maintain the press pressure constant. A supply valve that applies hydraulic pressure to simultaneously operate the small cylinder devices and a discharge valve that releases the hydraulic pressure in the small cylinder devices to simultaneously deactivate each small cylinder device are provided, and the pressure regulating valve is used to maintain the press pressure at a constant level. 1. A hydraulic press equipped with a vibration function, characterized in that a control device is provided to alternately open and close the supply valve and the discharge valve in each switchable cycle while operating the supply valve and the discharge valve.