JPH08300199A - Mechanical system press - Google Patents

Abstract

PURPOSE: To prevent a spring back occurring on a product by maintaining the closing state of a mechanical system press and also by adjusting this closing time, and to improve the working accuracy of a press product by eliminating the dispersion of the working accuracy, caused by the change of a die height. CONSTITUTION: In a mechanical system press, a pressure means (pressure chamber 8 and pressure adjusting device 10) displaying a load smaller than the press pressure of a press 1, is provided on a ram 4 side or on a bolster 5 side of the press 21. The closing of a press die 6 is completed when a stroke required until the ram 4 reaches a bottom dead point is left over. And also, the pressure means works on lowering and elevating strokes left over. Thus, the press is set so that the pressure state of the press die 6 is kept for a prescribed time while a load is held by the press die 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mechanical press machine capable of adjusting a mold closing time of a mechanical press machine so as to prevent a spring bag of a molded product and improve processing accuracy. .

[0002]

2. Description of the Related Art Since a hydraulic press machine can be stopped while the press die reaches the bottom dead center while maintaining the pressure applied to the product, it is easy to prevent the spring bag. . However, in a mechanical press machine, the press die moves up and down continuously from the bottom dead center to the top dead center, so it is impossible to stop the press die and the generation of the spring bag is unavoidable. Has been said.

Therefore, in the press work using the conventional mechanical press, the bending radius and angle of the die tool are corrected in advance by the amount corresponding to the spring bag to obtain a product having a prescribed shape. is there.

However, since the spring bag varies depending on the material, thickness, shape, etc. of the product, there is a problem that an engineer requires a high degree of skill in order to cope with this and obtain a highly accurate product. there were.

Further, in the mechanical press, the die height (die height) is caused by thermal expansion or deformation of the frame.
Change, the product processing accuracy will vary,
There is a problem in that the press die must be frequently stopped during processing to adjust the die height because the press die may be damaged.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and maintains the mold closing state of a mechanical pressing machine and adjusts the mold closing time. An object of the present invention is to provide a mechanical press machine capable of improving the processing accuracy of a pressed product by preventing a spring bag generated in the product and eliminating variations in processing accuracy due to changes in die height.

[0007]

In order to achieve the above-mentioned object, the mechanical press of the present invention changes the rotational movement of the crankshaft into a linear movement by a connection rod so that the connection rod is connected via a connection screw. In a mechanical press machine that moves up and down the rams connected together, the ram side or bolster side of the press machine is provided with pressurizing means that exerts a load smaller than the press pressure of the press machine, and the ram is at the bottom dead center. The mold closing of the press die is completed in the state where the stroke up to is reached, and the pressurizing means acts on the remaining descending and ascending strokes so that the press die holds the load. However, it is characterized in that the pressed state of the press die is maintained for a predetermined time.

Further, a pressurizing chamber in which a drilling machine supporting the ball portion of the connection screw is slidably moved up and down is provided in the ram, and a piston applied with a load smaller than the press pressure of the press machine is provided. It is preferable that the pressure adjusting chamber of the pressure adjusting device having the provided pressure adjusting chamber and the pressure adjusting chamber in the ram communicate with each other in a state in which a fluid is sealed.

In the ram, a pressurizing chamber in which a drilling machine supporting the ball portion of the connection screw is slidably moved up and down is provided, and a load smaller than the press pressure of the pressing machine is provided in the pressurizing chamber. A configuration may be provided in which a pressurizing unit that exerts the above is provided.

Further, the pressurizing means for exerting a load smaller than the press pressure of the press machine may be provided between the bolster and the frame of the press machine.

[0011]

In the above structure, the mold closing of the press die is completed with the stroke until the ram reaches the bottom dead center, and the pressing pressure of the press machine is applied to the remaining descending and ascending strokes. Since a small load acts on the press die, this load keeps the press die for the descending and ascending strokes left in the closed state and continues to pressurize the product. It is possible to accumulate and form high-precision products without a spring bag.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. (Embodiment 1) FIG. 1 is a partial sectional side view of a mechanical press and a pressure adjusting device according to the present invention. FIG. 2 is a partially enlarged view showing the ram side of FIG. FIG. 3 is a vertical sectional view of the pressure adjusting device of FIG. FIG. 4 is an explanatory view showing the operation of the mechanical press machine of FIG.

In FIG. 1, a connection rod 3 for converting a ram 4 into a linear motion is connected to a crankshaft 2 which is rotated by a motor (not shown) built in an upper portion of a frame 13. The connection rod 3 has a male screw 1 provided on the outer periphery of the connection screw 12.
It is possible to adjust the height by screwing 2b and rotating the connection screw 12.

Further, a ball portion 12a provided at a lower end of the connection screw 12 is rotatably supported by a drilling machine 7, and the drilling machine 8 is provided with a pressurizing chamber 8 provided in the ram 4.
It is slidably fitted to.

The pressurizing chamber 8 is provided as a hydraulic chamber forming an overload safety device in the conventional device. When the hydraulic pressure in the hydraulic chamber rises above a specified value, the safety device operates. The press machine 1 is stopped.

With such a configuration, the ram 4 is provided so as to be vertically movable along a guide (not shown), and can be vertically moved by driving the connection rod 3.

The two-dot chain line on the lower surface of the ram 4 in FIG.
Indicates. Below the ram 4, there is a support plate 13 for the frame 13.
The bolster 5 is fixed via a. Upper and lower press dies 6 are provided between the die 14 and the bolster 5, and products before pressing are placed in the press dies 6.

In such a mechanical press, a connecting pipe 16 is connected to the pressurizing chamber 8 by a coupler 15.
The connection pipe 16 is connected to a pressure adjustment chamber 11 in a pressure adjustment device 10 described later, and the pressure chamber 8 and the pressure adjustment chamber 11 including the connection pipe 16 are filled with fluid such as oil. .

The pressure adjusting device 10, as shown in FIG.
Inside the rectangular frame 18 fixed to the fixed plate 17, the cylinder 20 is attached to the support plate 19 a on one side with bolts 21.
The pressure adjusting chamber 11 is provided in the cylinder 20, and the piston 9 is slidably fitted in the pressure adjusting chamber 11. The coupler 15 fixed to the other end of the connecting pipe 16 is connected to the through hole 22 provided at the center of the support board 19a, so that the pressure adjusting chamber 11 and the pressure chamber 8 of the press machine 1 are connected. And are in communication.

A large-diameter adjusting screw 24 fixed to the rear end of the gas pressure cylinder 23 is screwed into the other supporting board 19b of the pressurizing and adjusting device 10, and the adjusting screw provided at the rear end of the adjusting screw 24 is adjusted. By rotating the handle 25, the hydraulic cylinder 23 can be moved back and forth.

The gas pressure cylinder 23 is a piston rod 9a.
The position of the piston 9 can be adjusted by moving the gas pressure cylinder 23 back and forth. The gas pressure cylinder 23 may be replaced by an elastic member using a hydraulic cylinder, a spring, or a disc spring, for example.

In FIG. 1, the press machine 1 of the first embodiment is
As described above, the pressurizing chamber 8 communicated with the pressurizing adjusting chamber 11 of the pressurizing adjusting device 10 is provided.
When the drilling machine 7 supporting the lowering of the pressurizing chamber 8 raises the hydraulic pressure in the pressurizing chamber 8, the pressurizing adjusting device 10
The piston 9 is moved backward, but since the piston 9 is pressurized from the rear by the gas pressure cylinder 23 at a predetermined pressure, the piston 9 resists the compression of the pressurizing chamber 8 on the press machine 1 side and the drilling machine 7 is lowered. It exerts a load.

In order for the press 1 to function properly, the ram 4 needs to have the remaining stroke when the ram 4 descends and the press mold 6 is completely closed.

Regarding this point, FIG. 4 (crankshaft 2
The rotation of the ram 4 is adjusted so that the press die 6 is closed before the crankshaft 2 descends from the top dead center 30 and reaches the bottom dead center 31. If so, the press die 6 can be kept in a stopped state from the time 32 when the press die 6 is closed to the time 33 when the press die 6 is released.

That is, in FIG. 4, the remaining descending stroke of the ram 4 is from the die closing 32 of the press die 6 to the bottom dead center 31.
Until then, the remaining ascending stroke of ram 4 is at bottom dead center 31
Corresponding to the release 33 of the press die 6,
During these descending strokes and ascending strokes, the press die 6 can be maintained in the closed state.

The stop time of the press die 6 is
Is determined by how much stroke the ram 4 takes after the mold is closed until the bottom dead center is reached. This time has to be decided for each product because the time when the spring bag disappears differs depending on the material and shape of the product, but if the remaining stroke is set with a margin, the stroke of the ram 4 should be roughly determined. You can

To adjust the stroke of this ram 4,
This can be done by rotating the connection screw 12 with respect to the connection rod 3 as described above.

Further, in order for the above-mentioned pressing machine 1 to function properly, means for absorbing the above-mentioned remaining stroke and maintaining a predetermined pressing pressure for the press die 6 is required.

For this reason, in this embodiment, in the pressurizing chamber 8 in the ram 4, the gas pressure cylinder 23 of the pressurizing adjusting device 10 side is arranged so as to exert a load smaller than the press pressure originally possessed by the press machine 1. The position is moved by the adjusting handle to adjust the internal volume of the pressure adjusting chamber 11 to apply a predetermined load to the pressure chamber 8 in the ram 4.

With such a configuration, the press die 6 is subjected to a predetermined load by the pressure adjusting device 10 in a state where the press die 6 is kept closed until the press die 6 is released. Accumulates the pressurizing energy to
It is possible to mold a product with a prescribed shape without a spring bag.

As described above, the press machine 1 of the first embodiment requires the separate pressure adjusting device 10, but the conventional hydraulic chamber is used as the pressurizing chamber 8 and the coupler of the connecting pipe 16 is used. 1
The conventional press machine 1 can be used as it is by simply connecting 5.

The piston 9 is formed by filling a block in the pressure adjusting chamber 11 of the pressure adjusting device 10 of the first embodiment.
If is fixed, it can be used as a normal press machine 1. At this time, it is necessary to adjust the stroke by rotating the connection screw 12. (Embodiment 2) In this embodiment, as shown in FIG. 5, a spring 26, which exerts a load smaller than the press pressure originally possessed by the press machine 1, is directly provided in the pressurizing chamber 8 of FIG. is there. As the spring 26, other pressurizing means, that is, a disc spring, oil, rubber or the like can be used. This allows
The same function as in the first embodiment can be achieved without providing the separate pressure adjusting device 10 as in the first embodiment. (Embodiment 3) In this embodiment, as shown in FIG.
On the side, a conventional one is used without being processed, and a spring 26 or a pressing means such as a disc spring, oil, rubber or the like is provided between the frame 13 and the bolster 5, and the bolster 5 has a frame 1
3 is provided with a guide pin 27 for guiding the vertical movement, and a load smaller than the press pressure originally possessed by the press machine 1 is applied to the bolster 5.

Also in this embodiment, when the bolster 5 is in the uncompressed state, the connection screw 12 is rotated so that the ram 4 has the remaining stroke while the press die 6 is closed, and the ram 4 is rotated. After the mold is closed by descending, the load of the spring acts on the bolster 5 to compress the spring 26.
The load of the spring 26 can be brought into a stopped state in which the mold closing of the press mold 6 is maintained and stopped.

[0034]

As described above, according to the mechanical press of the present invention, a load smaller than the press pressure of the press acts on the press die during the remaining descending and ascending strokes. The closed state of the press die is maintained, whereby the pressurizing energy to the product is accumulated, and it is possible to obtain a product having a prescribed shape with high processing accuracy without a spring bag.

Also, if the remaining stroke is set with a margin, the stroke of the ram can be roughly determined, and it is not necessary to perform strict die height adjustment as in the conventional case, and it is easy even without high skill. It is possible to perform highly accurate press working.

[Brief description of drawings]

FIG. 1 is a partial sectional side view of a mechanical press and a pressure adjusting device according to a first embodiment of the present invention.

FIG. 2 is a partially enlarged view showing a ram side of FIG.

3 is a vertical cross-sectional view of the pressure adjusting device of FIG.

FIG. 4 is an explanatory view showing the operation of the press machine shown in FIG.

FIG. 5 is a partial cross-sectional view showing a second embodiment of the present invention.

FIG. 6 is a partial cross-sectional view showing a third embodiment of the present invention.

[Description of sign]

 1 ... Press machine 2 ... Crank shaft 3 ... Connection rod 4 ... Ram 5 ... Bolster 6 ... Press type 7 ... Drilling machine 8 ... Pressurizing chamber 9 ... Piston 10 ... Pressurizing adjusting device 11 ... Pressurizing adjusting chamber 12 ... Connection screw 12a … Ball part of connection screw 13… Frame

Claims (4)

[Claims] 1. A ram (4) connected to a connection rod (3) via a connection screw (12) is moved up and down by changing the rotational movement of the crankshaft (2) into a linear movement by the connection rod (3). In a moving mechanical press machine, pressurizing means for exerting a load smaller than the press pressure of the press machine (1) is provided on the ram (4) side or the bolster (5) side of the press machine (1), and The die closing of the press die (6) is completed in the state where the stroke until the ram (4) reaches the bottom dead center is left, and the pressurizing means acts on the remaining descending and ascending strokes. As a result, the press die (6) is configured to maintain the pressurization state of the press die (6) for a predetermined time while holding the load. 2. A pressurizing chamber (8) in which a drilling machine (7) supporting a ball portion (12a) of the connection screw (12) is slidably moved up and down is provided in the ram (4). The pressure adjusting chamber (11) of the pressure adjusting device (10) having a pressure adjusting chamber (11) provided with a piston (9) capable of exerting a load smaller than the press pressure of the press machine (1). The pressurizing chamber (8) in the ram (4) is communicated with the fluid in a state in which a fluid is enclosed.
The mechanical press described. 3. A pressurizing chamber (8) in which a drilling machine (7) supporting a ball portion (12a) of the connection screw (12) is slidably moved up and down is provided in the ram (4). 2. The mechanical press machine according to claim 1, wherein a pressurizing means for exerting a load smaller than a press pressure of the press machine (1) is provided in the pressurizing chamber (8). 4. A pressurizing means for exerting a load smaller than a press pressure of the press machine (1) is provided between the bolster (5) and the frame (13) of the press machine (1). The mechanical press according to claim 1, which is characterized in that.