WO2004065112A1

WO2004065112A1 - Hydraulic system for die cushion device for press machine

Info

Publication number: WO2004065112A1
Application number: PCT/JP2003/016518
Authority: WO
Inventors: Tsutomu Shirakawa; Junichi Goto
Original assignee: Kosmek Ltd.
Priority date: 2003-01-20
Filing date: 2003-12-24
Publication date: 2004-08-05
Also published as: JP4455345B2; JPWO2004065112A1; AU2003296062A1; TW200417426A

Abstract

Elongate base plates (2) are arranged with intervals on the upper face of a cushion pad (1) of a die cushion device for a press machine. A large number of hydraulic cylinders (3) are arranged at each elongate base plate (2) with intervals in a length direction of the plate. It is constructed such that oil in an oil tank (20) is delivered to hydraulic chambers of the large number of the hydraulic cylinders (3) through a hydraulic pump (21). An elongate high-pressure container (41) for storing pressurized oil is communicated with each of the hydraulic chambers. The high-pressure container (41) is arranged between adjacent elongate base plates (2, 2).

Description

Description Hydraulic system of die cushion device for press machine

The present invention relates to a hydraulic system for a die cushion device for a press machine. Background art

Conventionally, this type of hydraulic system includes a large number of hydraulic cylinders arranged in a horizontal direction on the upper surface of a cushion pad of a die cushion device for a press machine as disclosed in Japanese Patent Application Laid-Open No. Hei 6-190644. The hydraulic pump is configured to supply the oil in the oil tank to the hydraulic chambers of the plurality of hydraulic cylinders via a hydraulic pump, and to receive the pressure oil in the hydraulic chamber from below through the cushion pins. is there. According to the conventional technique described above, even if there are variations in the length dimensions of the large number of cushion pins, the presser presses the piston into the hydraulic chamber through the cushion pins during press working. Accordingly, the cushion pin is excellent in that a variation in the length of the cushion pin can be absorbed and the cushion load at the time of press working can be almost uniformly transmitted to the cushion pin.

However, there has been a demand for improvement in setting the above-mentioned biston cushion stroke in a desired range.

That is, the pressurized oil supplied to the hydraulic chamber is essentially incompressible and has an extremely small allowable compression amount, so that the cushion stroke of the piston is inevitably small. Therefore, if the length of the many cushion pins has a large variation, the variation cannot be absorbed.

Prior to the present invention, the inventors of the present invention have set a conventional spring-type accumulator (or gas-type accumulator) in the hydraulic chambers of a number of hydraulic cylinders. Umulator). However, in this prior example, the piston stroke of the piston may be too large, and the piston may collide with the bottom wall of the hydraulic chamber.

An object of the present invention is to make it possible to set the cushion strokes of a large number of hydraulic cylinders provided in a hydraulic system of a die cushion device for a press machine to a desired range, and to make the hydraulic system compact. Disclosure of the invention

In order to achieve the above object, for example, as shown in FIG. 1, FIG. 2A and FIG. 2B, or FIG. The system was configured as follows.

A plurality of long base plates 2 are provided at intervals on the upper surface of the cushion pad 1 of the die cushion device for a press machine. A number of hydraulic cylinders 3 are provided on each long base plate 2 at intervals in the longitudinal direction of the long base plate 2. The oil in the oil tank 20 is supplied to the hydraulic chambers 10 of the above-mentioned many hydraulic cylinders 3 via the hydraulic pump 21, and the pressure oil in the hydraulic chamber 10 is supplied to the cushion pins 17 via the piston 9. It is configured to receive from below. A high-pressure container 41 for storing pressurized oil is communicated with each of the hydraulic chambers 10. The high-pressure vessel 41 is arranged between the adjacent long base plates 2 ■ 2.

The present invention has the following effects.

By storing the pressurized oil in the high-pressure container, the total amount of pressurized oil used in the hydraulic system of the die cushion device can be increased, and the allowable compression amount of the pressurized oil can be increased in accordance with the increase. Became possible. Therefore, by setting the internal volume of the high-pressure container to a predetermined value and adjusting the total amount of the pressure oil, the cushion strokes of the large number of hydraulic cylinders can be set to a desired range. Moreover, the present invention achieves the above effects by storing pressurized oil in a high-pressure vessel. The movable part necessary for the spring-type accumulator (or gas-type accumulator) of the above-mentioned invention can be omitted. Can be used. In addition, since the above-mentioned high-pressure vessel is arranged between the adjacent long base plates, it is not necessary to secure a dedicated space for installing the high-pressure vessel, and a compact hydraulic system can be provided.

Further, the present invention includes the following hydraulic system.

For example, as shown in FIG. 4 or FIG. 5, a plurality of the high-pressure vessels 41 are provided, and at least one high-pressure vessel 41 of the plurality of high-pressure vessels 41 is provided via an on-off valve 51. The hydraulic cylinder 10 communicates with the hydraulic chamber 10 of the hydraulic cylinder 3.

According to this invention, the amount of pressure oil corresponding to the internal volume of the high-pressure container connected to the on-off valve can be added or reduced by manually or automatically opening and closing the above-described on-off valve. Therefore, the amount of pressurized oil used for the die cushion function of the hydraulic system can be easily adjusted. As a result, it has become possible to easily set an appropriate amount of pressurized oil according to the cushioning capacity of the die cushion device. .

In the present invention, for example, as shown in FIG. 4, each of the plurality of high-pressure vessels 41 is connected to the hydraulic chamber 10 of the hydraulic cylinder 3 via an on-off valve 51. Is preferred. According to this invention, the amount of pressurized oil corresponding to the internal volume of each high-pressure vessel can be added or reduced by manually or automatically opening and closing the above-mentioned on-off valve, so that it is used for the die cushion function of the hydraulic system. The amount of pressurized oil can be adjusted over a wide range.

Further, in the above-mentioned hydraulic system, for example, as shown in FIG. 2A or FIG. 3 or FIG. 4, the high-pressure container 41 is formed in an elongated shape along the long base plate 2. Is preferred. According to the present invention, since the space between the adjacent long base plates 2 22 can be effectively used, it is possible to install a large-capacity high-pressure container and to make the hydraulic system compact. ' Further, in the above-mentioned hydraulic system, as shown in FIGS. 2A and 2B, for example, the oil tank 20 and the hydraulic pump 21 are connected between the long base plates 2 and 2 adjacent to each other. It is preferable to arrange them. According to the present invention, it is not necessary to secure a dedicated space for installing the oil tank and the hydraulic pump, so that the hydraulic system can be made more compact. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows one embodiment of the present invention, and is a system diagram of a hydraulic system.

FIG. 2A is a plan view of the above hydraulic system.

FIG. 2B is an elevational view corresponding to the view taken along line 2B-2B in FIG. 2A. FIG. 3 shows a first modified example of the present invention, and is a schematic view similar to the plan view of FIG. 2A described above.

FIG. 4 shows a second modification of the present invention, and is a schematic view similar to FIG. 3 described above. FIG. 5 is a schematic diagram showing a third modification of the present invention and is similar to FIG. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1, 2A, and 2B. A plurality of long base plates 2 are fixed on the upper surface of the cushion pad 1 of the press machine at predetermined intervals. Each long base plate 2 is provided with a number of hydraulic cylinders 3. These hydraulic cylinders 3 are fixed at predetermined intervals in the longitudinal direction of the long base plate 2. Thus, the large number of hydraulic cylinders 3 are arranged in a grid in plan view. In addition, a flange 4 for a plug is attached to a place where the above-mentioned hydraulic cylinder 3 is not arranged, at a place corresponding to the long base plate 2.

The hydraulic cylinder 3 is configured as follows.

A housing 5 is provided on the support surface 2 a of the long base plate 2 It is fixed in a sealed state via Porto 7. A piston 9 is inserted into the cylinder hole 8 of the housing 5 in a hermetically sealed manner, and an oil pressure chamber 10 is formed between the piston 9 and the support surface 2a. The hydraulic chamber 10 directly faces the support surface 2a.

In the long base plate 2, a main flow path 13 extending in the horizontal direction and a number of branch paths 14 extending in the upward and downward directions are formed. The hydraulic chamber 10 of the hydraulic cylinder 3 communicates with the main flow path 13 via the branch path 14. The cushion pad 1 is pressed upward by a pneumatic pressing force applying means (not shown). Further, a presser holding type (not shown) is arranged above the above-mentioned many hydraulic cylinders 3, and a number of cushion pins 17 are arranged between the presser-holding type and the above-mentioned many pistons 9. You. The number of these cushion pins 17 varies depending on the capacity and model of the press machine, but is in the range of several tens to 200 per one die-cutting device.

The oil in the oil tank 20 is pressurized by an air-hydraulic booster pump 21 which is a hydraulic pump, and the pressure oil discharged from the booster pump 21

Through 2, it is supplied to the main channel 13 in the long base plate 2. The discharge pressure of the booster pump 21 can be changed by adjusting the pressure of the compressed air of the pneumatic pressure source 24 to a predetermined pressure by the pressure reducing valve 25.

The booster pump 21 is provided with a suction valve 26 and a discharge valve 27. Further, a filter 29 and a check valve 30 are mounted on the pressure oil passage 22. A relief valve 31 branches from between the filter 29 and the check valve 30.

_ Further, a pressure ensuring means 33 is branched off from the pressure oil passage 22 on the downstream side of the check valve 30. The pressure assurance means 33 includes a throttle valve 34 and a three-position switching valve 35 connected in series. When the pressure of the pressure oil passage 22 is lower than the set pressure range, the switching valve 35 is brought to the low pressure closing position X, and the pressure is set at the set pressure. When the pressure exceeds the range, the high-pressure closing position Y is set, and the opening position Ζ is set in the middle of switching between these two positions X ■. Reference numeral 37 denotes an inlet-side filter, and reference numeral 38 denotes a shutoff valve.

During the above-mentioned switching of the switching valve 35, the pressure oil in the hydraulic chamber 10 of the hydraulic cylinder 3 causes the throttle valve 34 and the switching valve 35 at the opening position Ζ to communicate with each other. Only a small amount is discharged to the oil tank 20 through the above. Thereby, even if the temperature of the hydraulic oil in the hydraulic chamber 10 increases due to the operation of the press machine, the pressure in the hydraulic chamber 10 is prevented from abnormally increasing.

In this embodiment, the discharge pressure of the booster pump 21 is about 2.5 Ρ Ρa, the relief set pressure of the relief valve 31 is about 7 MPa to about 1 OMPa, while the press machine is operating. The maximum pressure of the pressure oil in the hydraulic chamber 10 is about 5 OMPa, and the set pressure range of the pressure assurance means 33 is about 3.5 MPa to about 5 MPa.

Further, a long high-pressure container 41 for storing pressure oil is connected to the pressure oil passage 22 downstream of the check valve 30. More specifically, the high-pressure container 41 is formed of a thick-walled cylinder elongated along the long base plate 2, and a plurality of the high-pressure containers 41 are provided between the adjacent long base plates 2. (Only one high-pressure vessel 41 is shown here). Each end of the high-pressure vessel 41 in the longitudinal direction is connected to the main flow path 13 of each long base plate 2 via a connection pipe 42.

The oil tank 20 and the booster pump 21 are also arranged between the adjacent long base plates 22. In addition, the above-mentioned pressure assurance means 3 3 ′ non-return valve 30 ■ relief valve 3 1 ■ valve device 43 integrally incorporating stop valve 38 is fixed to the long base plate 2.

An experimental example of the hydraulic system having the above configuration is shown below.

The number of the hydraulic cylinders 3 to be installed is 16 1, and the total volume of the hydraulic chamber 10 described above for each hydraulic cylinder 3 and the piping path (the main flow path 13 and the branch path 14 And the total volume was about 6 liters (about 6000 cm ³ ). The internal volume of the high-pressure vessel 41 according to the present invention was set to about 4 liters (about 4000 cm ³ ). Under the above conditions, when the cushion load is 120 tons and the number of the used cushion pins 17 is 20 and the high pressure vessel 41 is not installed, the cushion of the piston 9 of the hydraulic cylinder 3 is not used. The cushion stroke was about 3 mm. On the other hand, when the high-pressure vessel 41 was installed, the cushion stroke of the piston 9 was about 5 countries.

The above embodiment can be modified as follows.

As shown in FIG. 2B, the height of the high-pressure container 41, the oil tank 20, the booster pump 21 and the valve device 43 is the height of the upper end surface of the piston 9 of the hydraulic cylinder 3. It is preferable to arrange it so that it is as follows, but it is also possible to arrange it so that it is slightly higher than its upper end surface.

Needless to say, the hydraulic cylinder 3 is not limited to the illustrated structure, and various structures can be adopted.

Instead of providing a plurality of high-pressure vessels 41, only one may be provided.

The valve device 43 may be disposed between the adjacent long base plates 2′2 instead of being fixed to the long base plate 2.

At least one of the valve device 43, the oil tank 20, and the booster pump 21 may be disposed outside the cushion pad 1. Instead of separately providing the throttle valve 34 and the switching valve 35, the throttle valve 34 may be incorporated in the switching valve 35.

FIGS. 3 to 5 show first to third modifications of the present invention, and are schematic views similar to FIG. 2A described above. In these modified examples, members having the same functions as those in the above-described embodiment are given the same reference numerals in principle.

The first modified example of FIG. 3 is configured as follows. On both left and right sides in FIG. 3, two long high-pressure vessels 41 are installed in series between the adjacent long base plates 2 ■ 2, and these high-pressure vessels 4 1 ′ 4 1 It is connected in series to a pair of connecting pipes 4 2 ■ 4 2. -The second modification of FIG. 4 is configured as follows.

Two long high-pressure vessels 1 are installed separately in each space between the adjacent long base plates 2 ■ 2, and the outer ends of the high-pressure vessels 4 1 in the longitudinal direction are opened and closed valves 5 1 Is connected to the connection pipe 42 through the above. The above-mentioned on-off valve 51 is preferably operated automatically by an actuator such as an electric motor or a pneumatic cylinder, but may be operated manually.

The third modification of FIG. 5 is configured as follows.

On the left and right sides in FIG. 5, three spherical high-pressure vessels 41 are connected in series between the adjacent long base plates 2 ′ 2 through the on-off valve 51, and outwardly. The high-pressure vessel 41 to be located is connected to the connection pipe 42 via another on-off valve 51. In addition, at the center in the left-right direction in FIG. 5, two spherical high-pressure vessels 41 are installed in each space between the adjacent long base plates 2′2 in a state of being separated. On the left side of the central portion, the outer end of each high-pressure vessel 41 is connected to the connection pipe 42 via the on-off valve 51. On the other hand, on the right side of the central portion, the on-off valve 51 is omitted, and the outer end of each high-pressure vessel 41 is directly connected to the connection pipe 42.

The above embodiments and modified examples can be further modified as follows.

The on-off valve 51 may be connected to at least one high-pressure vessel 41 of the plurality of high-pressure vessels 41. Therefore, in the second modified example of FIG. 4, a plurality of optional on-off valves 51 may be omitted.

Further, the shapes of the plurality of high-pressure vessels 41 are not limited to the exemplified long shapes and spherical shapes.

Claims

The scope of the claims

1. A plurality of long base plates (2) are provided at intervals on the upper surface of the cushion pad (1) of the die cushion device for press machine, and a number of hydraulic cylinders (3) are provided on each long base plate (2). Are provided at intervals in the longitudinal direction of the long base plate (2), and the oil in the oil tank (20) is supplied to the hydraulic chambers of the hydraulic cylinders (3) via the hydraulic pump (21). (10), so that the pressure oil in the hydraulic chamber (10) receives the cushion pin (17) from below through the piston (9),

A high-pressure container (41) for storing pressurized oil is communicated with each of the above-mentioned hydraulic chambers (10), and the high-pressure container (41) is arranged between adjacent long base plates (2) and (2). A hydraulic system for die cushion devices for press machines, characterized by the following.

2. In the hydraulic system of the die cushion device for a press machine described in claim 1,

A plurality of the high-pressure containers (41) are provided, and at least one of the plurality of high-pressure containers (41) is connected to the hydraulic cylinder (3) via an on-off valve (51). 3.) A hydraulic system for a press machine dicushion device, wherein the hydraulic system communicates with the hydraulic chamber (10).

3. In the hydraulic system of the die cushion device for a press machine described in claim 2,

The plurality of high-pressure vessels (41) are respectively connected to the hydraulic chamber (10) of the hydraulic cylinder (3) via an on-off valve (51). Hydraulic system for die cushion device for press machine.

4. Claims (1) and (2) [In the hydraulic system of the die cushion device for press machine described above,

The hydraulic system for a die cushion device for a press machine, wherein the high-pressure container (41) is formed in an elongated shape along the long base plate (2).

5. In the hydraulic system of the die cushion device for a press machine according to claim 1 or 2,

A die cushion device for a press machine, wherein the oil tank (20) and the hydraulic pump (21) are arranged between adjacent long base plates (2) and (2). Hydraulic system.