JPH0614896Y2 - Damper device for die cushion device - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a damper device for cushioning a shock when a die cushion device used in a press machine returns to its upper limit.

[Conventional technology]

FIG. 4 shows a die cushion device 20 incorporated in a press machine for holding blank creases. The die cushion device 20 includes a conventional hydraulic damper device 21 for cushioning the impact at the time of returning to the upper limit. Be prepared.

Inside the bed 22 of the press machine, there are arranged first and second cushion cylinders 23 and 24 which are vertically arranged in two stages, and these cushion cylinders 23 and 24 are partitioned by a partition member 25. Each cushion cylinder 23,
The cushion pistons 26 and 27 of 24 are cylindrical rods 28.
Further, a cushion pad 30 which is vertically movable while being guided by a guide member 29 is connected to the cushion piston 26 via a connecting cylinder 31 and a connecting rod 32. Bed 22 for cushion pad 30
A cushion pin 34 vertically inserted through the upper plate 22A and the bolster 33 is provided upright.
A blank holder 36 that is vertically movable with respect to a lower mold 35 attached to the bolster 33 is provided on the top of the.

The piston rod 37 of the damper device 21 is inserted into the inside of the cylindrical rod 28.
Is connected to the cylindrical rod 28 at the upper portion 37A, the lower portion penetrates the bottom plate 22B of the bed 22 and extends downward, and the damper piston 38 is fixedly provided at the tip thereof. The damper piston 38 is provided on the bottom plate 22 of the bed 22.
The damper cylinder 39 attached to B can freely move in and out, and the damper cylinder 39 is arranged in an oil chamber 41 filled with damper oil inside a case 40.

A tank 43 is connected to the air cushion chamber 42 inside the first cushion cylinder 23, and the tank 43 is connected to an air supply source via a regulator 44. The air cushion chamber 42 inside the first cushion cylinder 23 and the air cushion chamber 45 inside the second cushion cylinder 24 communicate with each other through a small hole 46 and a central hole 47 of the cylindrical rod 28. As a result, air having a predetermined pressure is supplied to both the air cushion chambers 42 and 45.

When the blank 50 is pressed by the upper die 49 and the lower die 35 by lowering the slide 48, the flange portion 50A at the end of the blank 50 is sandwiched between the upper die 49 and the blank holder 36, and the slide 48 descends. Accordingly, the cushion piston 26 is pushed down via the blank holder 36, the cushion pin 34, the cushion pad 30, the connecting cylinder 31, and the connecting rod 32, and the cushion piston 27 is also pressed down via the tubular rod 28. Therefore, the air in the first and second cushion cylinders 23 and 24 and the air in the tank 43 are compressed, and the upward cushioning force due to the air compression acts on the black holder 36 during the pressing work, so that the blank 50 is flanged. Part 50A
Pressed while preventing wrinkles. At this time, the damper piston 38 becomes the piston rod 3
7 descends together with the cushion pistons 26 and 27.

When the slide 48 starts to move up after reaching the bottom dead center, the cushion piston 26,
27, the cushion pad 30, the blank holder 36, and the like are raised, and the damper piston 38 is also raised by the piston rod 37. When these ascents approach the ascent limit, the damper piston 38 begins to be fitted into the damper cylinder 39,
This fitting is supplied to the oil chamber 41 to transfer the oil existing in the damper cylinder 39 to the damper piston 38 and the damper cylinder 3.
This is performed while pushing out from the minute gaps 51 and 52 provided between the damper piston 38 and 9, and in other words, the damper piston 38 ascends while receiving the damper force by the downward hydraulic pressure near the ascending limit. Therefore, the returning speed of the cushion pistons 26, 27 when approaching the rising limit is reduced, and the impact at the time of returning to the rising limit is alleviated, so that the die cushion device 20 and the press-molded blank 50 are protected. .

[Problems to be solved by the invention]

In the above-described conventional technique, the damper device 21 is provided in a state of protruding below the die cushion device 20, and therefore the height dimension of the die cushion device 20 including the damper device 21 becomes large, and the die size of the press machine is increased accordingly. It is necessary to secure a large space above and below for assembling the cushion device 20. Considering a space necessary for performing maintenance work of the die cushion device 20 and a space for disposing the scrap conveyor when the press machine is provided with a scrap conveyor, for example, a larger space is provided around the die cushion device 20. It will have to be secured.

An object of the present invention is to make it possible to reduce the height dimension of a die cushion device including a damper device, which is advantageous in terms of space.

[Means for solving problems]

For this reason, in the damper device of the die cushion device according to the present invention, the cushion pistons are vertically movably arranged inside the respective cushion cylinders which are partitioned by the partition member and are arranged in a plurality of upper and lower stages. In a die cushion device that generates a cushioning force by compressing air in a cylinder, a damper piston is vertically movable between the partition member and a cushion piston of the cushion cylinder below the partition member, Between the air damper chamber above the damper piston and the air cushion chamber of the cushion cylinder above the partition member, there is provided a valve means for allowing air to flow into the air damper chamber from the air cushion chamber, and from the air damper chamber to the air cushion chamber. Air throttle that throttles air It is characterized in that provided the road.

[Action]

When the cushion piston is pushed down, the air in the cushion cylinder is compressed, and the cushion force is generated as in the conventional case. Further, when the cushion piston is pushed down, the compressed air in the air cushion chamber of the cushion cylinder above the partition member flows into the air damper chamber through the valve means, and the damper piston descends. When the cushion piston rises and approaches the upper limit, the damper piston that rises together with the cushion piston of the cushion cylinder below the partition member causes the air in the air damper chamber to flow into the air cushion chamber through the air throttle passage. At this time, the air flowing into the air cushion chamber is throttled by the air throttling passage and the air flow rate is restricted.Thus, this throttling action reduces the speed of the cushion piston near the ascent end, and the impact when the ascent end is restored. Is alleviated.

The damper piston, the air damper chamber, etc. constitute a pneumatic damper device, which is arranged in the cushion cylinder. In other words, the damper device is incorporated inside the die cushion device. The height dimension of the die cushion device including the damper device is small.

〔Example〕

FIG. 1 shows an embodiment of the present invention. Since the basic structure of the die cushion device in this embodiment is the same as that of the prior art already described, the same members are designated by the same reference numerals, and the description thereof will be omitted. Shortened or omitted.

The damper piston 1 is provided between the partition member 25 partitioning the first and second cushion cylinders 23 and 24 of the die cushion device 20 and the cushion piston 27 of the second cushion cylinder 24 below the partition member 25. The damper piston 1 is arranged in the damper cylinder 2 and is vertically movable in a free state with respect to the cylindrical rod 28. As shown in FIGS. 2 and 3, the damper cylinder 2 is fixed to the lower surface of the partition member 25 with bolts 3, and
The lower surface is an opening 4, and the damper piston can descend to the position of the locking projection 2A provided on the lower portion of the inner peripheral surface of the damper cylinder 2. The space above the damper piston 1 is an air damper chamber 5 surrounded by the partition member 25, the damper cylinder 2, and the damper piston 1.

A ring-shaped elastic member 6 made of urethane rubber is placed on the upper surface of the cushion piston 27 on the outer periphery of the cylindrical rod 28, and the elastic member 6 has a diameter that allows loose fitting in the opening 4. The thickness is larger than the height of the locking projection 2A.

A check valve 7 is attached to the partition member 25, and the check valve 7 serves as a valve means for allowing air to flow only from the air cushion chamber 42 of the first cushion cylinder 23 above the partition member 25 to the air damper chamber 5. ing. Partition member 2
A passage 8 opening to the air damper chamber 5 and a passage 9 opening to the air cushion chamber 42 are formed in the valve 5. An orifice member 10 is interposed between these passages 8 and 9 and is provided inside the orifice member 10. The passages 8 and 9 are communicated with each other by the small passage 11 serving as an orifice. The tubular member 12 is provided at the center of the partition member 25 in which the tubular rod 28 is inserted.
Is fixed, and a minute gap 13 is provided between the cylindrical member 12 and the cylindrical rod 28.

In the present embodiment, the air in the air damper chamber 5 is throttled by the small passages 11 and the gaps 13 to form the air cushion chamber 42.
An air throttle passage 14 that allows the air to flow in is formed. Further, the damper piston 1, the damper cylinder 2, etc. constitute a pneumatic damper device 15.

Next, the operation will be described.

When the slide 48 descends and the blank 50 is pressed by the upper die 49 and the lower die 35, the cushion pistons 26 and 27 of the first and second cushion cylinders 23 and 24 are pushed down as in the prior art. The air inside the cushion cylinders 23 and 24 and the tank 43 is compressed, and an upward cushioning force acts on the blank holder 36, and wrinkles occur in the flange portion 50A sandwiched between the upper mold 49 and the blank holder 36. The blank 50 is pressed while being prevented. At this time, the compressed air in the air cushion chamber 42 in the first cushion cylinder 23 passes mainly through the check valve 7 and the air damper chamber 5
And thus the damper piston 1 descends to the position of the locking projection 2A. This is shown in FIG.

If slide 48 moves up after reaching bottom dead center,
The cushion pistons 26 and 27 of the second cushion cylinders 23 and 24 start to rise due to the elastic force of the compressed air as described above, and the elastic member 6 placed on the upper surface of the cushion piston 27 also rises. When reaching the upper limit, the elastic member 6 comes into contact with the damper piston 1 through the opening 4, and due to this contact, the elastic member 6 is compressed and deformed while pushing up the damper piston 1, and due to this compression deformation, the upper limit is reached. The first impact mitigation is done nearby.

When the cushion pistons 26 and 27 further rise, the damper piston 1 also rises, so that the air in the air damper chamber 5 flows into the air cushion chamber 42 through the passage 8, the small passage 11, the passage 9 and the gap 13. Since the air flow rate at this time is narrowed by the throttling action of the small passage 11 and the gap 13, the damper piston 1 is acted on by the downward force of the air pressure in the air damper chamber 5, and as a result, The second shock relaxation near the rising limit is performed, and the rising speed of the cushion pistons 26, 27 decreases, reaching the rising limit as shown in FIG.

According to the damper device 15 described above, the conventional damper device 21
Similarly to the above, the shock at the time of returning to the upper limit of the die cushion device 20 can be alleviated, and the damper device 15 is arranged in the second cushion cylinder 24 and is incorporated in the die cushion device 20, so that the damper device 15 is provided. The height dimension of the die cushion device 20 including the device 15 can be reduced, and it is not necessary to secure a large space in the vertical direction for disposing the die cushion device 20 in the press machine, which is advantageous in terms of space.

Further, since the damper device 15 is pneumatic, unlike the conventional hydraulic damper device 21, it is not necessary to prepare a hydraulic circuit and hydraulic equipment, and the structure can be simplified accordingly.

Further, the damper force is not generated only by the air throttle passage 14 constituted by the small passage 11 and the gap 13,
Since the damper force is also generated by the compressive deformation of the elastic member 6, the impact energy can be effectively absorbed.

Further, since the check valve 7, the orifice member 10 having the small passage 11, and the gap 13 can be provided in the partition member 25, it is not necessary to prepare a special member for arranging them, and this point Also in, the simplification of the structure can be achieved. In addition, the orifice member 10 having the small passage 11 provided therein has the partition member 2 by removing the plug member 16.
5, the damper force of the damper device 15 can be appropriately changed and adjusted by replacing the orifice member 10 with the small passages 11 of different sizes.

In the die cushion device 20 of the present embodiment described above, the cushion cylinder has a two-tier structure, but the damper device according to the present invention has three cushion cylinders.
It can also be applied to items with multiple steps. Further, in the present embodiment, the impact is alleviated also by the compressive deformation of the elastic member 6, but the elastic member 6 may not necessarily be provided. However, if the elastic member 6 is provided, the impact can be alleviated in two stages as described above, and a large impact energy can be surely absorbed.

Further, in the present embodiment, the air throttle passage 14 is composed of the small passage 11 and the gap 13, but the air throttle passage may be only one of them, and the structure thereof is the small passage 11 and the gap 13 of the present embodiment. However, it is not limited to this, and it is possible to squeeze the air from the air damper chamber 5 into the air cushion chamber 42 if necessary.

Further, in the present embodiment, the valve means for allowing the air to flow from the air cushion chamber 42 to the air damper chamber 5 was the check valve 7, but this may be a spool type, for example, and its type is arbitrary.

Further, although the die cushion device 20 of the present embodiment is for holding the blank wrinkle, the damper device according to the present invention can be applied to a die cushion device for blank ejection.

[Effect of device]

According to the present invention, since the damper device is incorporated inside the die cushion device, the height dimension of the die cushion device including the damper device can be reduced, which is advantageous in terms of space.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention, and FIG. 2 is a first view showing a state when the cushion piston reaches the lower limit.
FIG. 3 is an enlarged view of an essential part of the drawing, FIG. 3 is an enlarged view of an essential part of FIG. 1 showing a state when the cushion piston reaches the upper limit, and FIG. 4 is a view similar to FIG. 1 showing a conventional example. . 1 …… Damper piston, 2 …… Damper cylinder, 5 ……
Air damper chamber, 6 ... Elastic member, 7 ... Check valve as valve means, 11 ... Small passage, 13 ... Gap, 14 ... Air throttle passage, 15 ... Damper device, 20 ... Die cushion device , 22 ... bed, 23 ... first cushion cylinder, 24 ... second cushion cylinder, 25 ... partition member, 26, 27 ... cushion piston, 30 ... cushion pad, 33 ... bolster, 35 ... Lower mold, 48
...... Slide, 42, 45 …… Air cushion room, 49
…… Upper mold, 50 …… Blank.

Claims (1)

[Scope of utility model registration request] 1. A cushion piston is movably arranged vertically inside each of the cushion cylinders which are partitioned by partitioning members and have a plurality of upper and lower stages, and the cushion force is generated by the compression of air in the cushion cylinder by these cushion pistons. In the die cushion device for generating the above, a damper piston is vertically movably arranged between the partition member and a cushion piston of the cushion cylinder below the partition member, and an air damper chamber above the damper piston is provided. Valve means for inflowing air from the air cushion chamber to the air damper chamber between the air cushion chamber of the cushion cylinder above the partition member, and an air throttle passage for squeezing air from the air damper chamber to the air cushion chamber. Diquish characterized by having and Damper device of the device.