JPH04300034A - Precision punching die assembly - Google Patents

Abstract

PURPOSE:To offer the precision punching die assembly which can manufacture a product in which a precise punched hole is formed without spoiling the beauty of a bridge part in which a sheet-like stock remains and its torn surface, and also, to prevent the damage of a punching die. CONSTITUTION:This assembly constitutes a characteristic feature of attaching integrally a stripper 3 to a ram 22 of a press machine through a punch die set 13, placing a punch plate unit 12 so as to be movable vertically in the stripper 3, protruding the tip part of a punch 5 provided on the punch plate unit 12 to the lower part through a punch guide hole 71 provided on the stripper 3, and also, providing a punch plate unit driving means 14 for moving the punch plate unit 12 independently from the ram 22.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention is a precision punching tool used in the manufacture of thin plates in which precise punching holes are continuously formed in relatively thin plate-shaped materials such as lead frames and punched metal strips. It concerns a mold device.

0002

2. Description of the Related Art FIG. 4 shows a general example of a conventional precision punching die device for continuously forming precise punching holes in a thin metal plate. Hereinafter, a conventional punching die device will be explained with reference to FIG.

The punching die device shown in FIG. 4 is composed of an upper die 39 and a lower die 42, and is mounted on a press machine.

The upper die 39 includes a punch plate 32 having a punch 33 and a guide pin 34, a stripper 38 and a guide bush 46 held by a hanger 37.
It is composed of a die set 35 equipped with. The upper mold 39 is attached to a ram 43 of a press machine, and can move up and down in a straight line. Further, a spring 36 is provided between the stripper 38 and the die set 35. Further, the stripper 38 is provided with a punch guide hole 70 for guiding the punch 33.

On the other hand, the lower die 42 is connected to the punch 33 of the upper die 39.
A die 40 and an upper mold 39 are provided at positions facing each other, and the hole diameter and relative pitch are controlled with high precision with respect to the punch 33.
The die set 41 includes a guide post 47 that fits into a guide bush 46 of the press machine, and is fixed to a bolster 44 of the press machine. The die 40 is provided with a guide bush 45 that engages with the guide pin 34 of the upper die 39.

[0006] The material 31 is a strip-shaped thin plate wound into a cylindrical shape, and when punching holes are to be manufactured, the material 31 is drawn out and placed between the upper mold 39 and the lower mold 42 of the punching die device. After placing the material 31 in a position for punching, when the punching die device is closed under the guidance of the guide post 47, the punch 33 of the upper die 39 is pressed and restrained by the stripper 38. , and the punch 33 is further inserted into the punch receiving hole 80 of the die 40 of the lower mold 42 . A punched hole having substantially the same cross-sectional shape as the punch 33 is formed in the material 31.

At this time, the positional accuracy of the upper mold 39 and the lower mold 42 is determined by the sliding accuracy of the guide bush 46 of the upper mold 39 and the guide post 47 of the lower mold 42. By further inserting the guide pin 34 of the punch plate 32 into the guide bush 45 provided on the die 40, the behavior of the stripper 38 is stabilized. can be positioned with high precision.

After forming the punched holes, the upper mold 39 is raised, the punch 33 is extracted from the die 40, and the material 31 is fed in pitches to repeat the punching operation in sequence.

When punching holes are formed in the material 31, if the surface of the material 31 at the processing position is not strongly pressed and restrained, various deformations may occur in the shape of the punched holes. For example, as shown in FIG. 3, when forming the punched hole 27 while leaving the crosspiece 28 with a narrow width 30 close to the thickness 29 of the material 31, the deformation 48 of the crosspiece 28 as shown in FIG. Also, the punched hole 27 may be twisted 49 as shown in FIG. 5(b), or sag 50 as shown in FIG. 5(c).
and a burr 51, and a depression 52 as shown in FIG. 5(d).
etc. will occur. Therefore, conventionally, the spring 36 that biases the stripper 38 has been strengthened, or a cylinder containing gas has been provided in order to pressurize the stripper 38 even more strongly.

0010

[Problems to be Solved by the Invention] However, in the conventional punching die device, the pressing force that presses and restrains the portion of the material 31 in the vicinity of the punched portion at the punching position in the device is limited to the amount of pressure applied to the punching die as described above. The spring 36 provided in the mold
and the gas cylinder, and the spring 36
It has been difficult and unstable to obtain sufficient pressing force using only biasing methods such as the above. Further, the spring 36 and the gas cylinder are connected to the stripper 38 by the punch 33 and the guide pin 34.
etc., it is difficult to install it near the punching position of the device, and it has to be placed at a remote location, and the stripper 38 is sufficiently pressed in a stable state to restrain the material 31. It was difficult to do so.

Further, in the conventional punching die device described above, the body of the punch 33 is integrally attached to the punch plate 32, and the punch guide hole 70 is connected to the punch plate 3.
Since the punch 33 is provided in the stripper 38 which behaves independently from the die 40, if there is unstable behavior such as load deviation when the upper die 39 and the lower die 42 are closed, the punch 33 may deviate from the predetermined position with respect to the die 40. If the punching process is performed in this state, the punched hole will be deformed and the appearance of the product will deteriorate significantly, and in severe cases, the tip of the punch 33 will be lowered as shown in Figure 6. There have been problems in that accidents such as breakage of the die 40 or loss of the cutting edge of the die 40 occur.

0012

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention integrally attaches a stripper to the ram of a press machine via an upper die set, and has a punch plate unit movable up and down inside the stripper. The punch plate unit is provided with a punch plate unit driving means that causes the tip of the punch provided in the punch plate unit to project downward through a punch guide hole provided in the stripper, and that causes the punch plate unit to move independently of the ram. Features.

[0013] The punch is also characterized in that it comprises a punch holder and a punch body, and the punch body can be moved minutely in a direction perpendicular to the punching direction with respect to the punch holder.

[0014]

[Operation] According to the present invention, since the stripper is integrally attached to the ram of the press machine via the upper die set, the pressing force applied to the stripper is very large and stable, and moreover, the stripper As a result, the material can be pressed and restrained in the vicinity of the punching position of the material, and as a result, the material can be pressed and restrained in a strong and stable state. Then, while the material is pressed and restrained in this way, the punch can be operated by an independent punch plate unit driving means, and the punching pressure at that time can be set optimally, so ideal punching can be achieved. Able to perform work. Therefore, various disadvantages as shown in FIG. 5, which were observed in the conventional example, are eliminated, and a product with a good punched shape can be obtained.

[0015] Furthermore, with the configuration as described in claim 2, since the punch body is built into the punch holder,
The bending strength of the punch can be improved, and the position of the punch body can be moved slightly in the direction perpendicular to the punching direction, so even if the punch plate unit has unstable behavior, the punch body can be moved slightly. However, it is guided to the punch guide hole of the stripper, so that punching can be performed at the correct position, and breakage of the tip of the punch as in the conventional example can be prevented.

[0016]

Embodiment An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

In FIG. 1, 17 is a ram 22 of a press machine.
The upper die 21 is attached to the bolster 23, and the lower die 21 is attached to the bolster 23, and the material 19 is punched out by the lowering of the ram 22.

The upper mold 17 includes a punch plate unit 12
, a stripper 3, a guide bush 24, a hydraulic cylinder device (punch plate unit driving means) 14, and an upper die set 13. The stripper 3 is integrally fixed to the ram 22 via the upper die set 13, and is configured so that the pressing force when the ram 22 descends is directly transmitted to the stripper 3. A punch plate unit 12 is housed in a space formed between a recess provided on the top surface of the stripper 3 and the lower surface of the upper die set 13.

The punch plate unit 12 includes a punch plate 1, a backing plate 10, a punch 5, and a guide pin 2. The punch plate 1 and the backing plate 10 are connected by bolts 15, and the punch 5 and guide pin 2 are fixed to the punch plate 1 and protrude downward, respectively. Punch plate unit 1
2 moves up and down within the space and is urged upward by a return spring 11.

The hydraulic cylinder device 14 is connected to the upper die set 1.
3, and the hydraulic passage 1 is provided in the cylinder portion 14a.
Pressure oil from an external hydraulic source is introduced via 4b. The plunger portion 14c of the hydraulic cylinder device 14 is connected to the backing plate 10 of the punch plate unit 12, and when pressure oil is introduced into the hydraulic cylinder device 14 from the hydraulic source, the punch plate unit 12 and eventually the punch 5 are lowered. , is configured to punch out the material 19. The hydraulic cylinder device 14 applies a pressing force to the punch plate unit 12 that is two to three times the punching force required to punch out the material 19.

As shown in FIG. 2, the punch 5 includes a punch holder 5b consisting of a pair of divided bodies 7 and 8, a punch body 5a restrained and supported by this punch holder 5b, and a pair of divided bodies 7 and 8. It consists of a pin 9 that connects the T-shaped grooves 7a and 8a are formed in each of the pair of divided bodies 7 and 8, and these grooves are combined to form a space that restrains and supports the punch body 5a. Although the punch body 5a is completely restrained from moving in the vertical direction (punch punching direction) with respect to the punch holder 5b,
A slight movement in the left and right direction is allowed.

The lower surface of the stripper 3 serves as a pressing surface for pressing the material 19. The stripper 3 is also provided with a punch guide hole 71 through which the tip of the punch 5 is inserted, and a hole 72 through which the guide pin 2 is inserted and guided. The tip of the punch 5 and the punch guide hole 7
1 and the positioning is such that the clearance between the two is about 10 microns.

The lower mold 21 includes a die 18 having a punch receiving hole 73 facing the punch 5 and a guide bush 4 for receiving a guide pin facing the guide pin 2, the guide post 25, and the die 18. 18 and a lower die set 20 on which the die 18 is placed and supported, and is fixed to a bolster 23. A material 19 is placed on the die 18.

Next, the operation of the punching die device will be explained.

After placing the material 19 at the punching position between the upper mold 17 and the lower mold 21 of the punching die device, the upper mold 17
is guided by the guide post 25, and further lowers while its position is regulated by engagement of the guide pin 2 with the guide bush 4, and the stripper 3 receives direct pressure from the ram 22, presses the material 19, and releases the die 18. restrain on top. Since the pressure at this time is from the ram 22,
The material 19 can be restrained with a very large pressing force.

When the material 19 is restrained at the punching position within the device, the hydraulic cylinder device 14 is activated, and the punch plate unit 12 is lowered while being controlled to an appropriate pressure, and accordingly, the punch 5 punches the material 19. Punching, material 1
The punch receiving hole 73 is inserted into the punch receiving hole 73 while a punching hole of a predetermined shape is formed in the punch hole 9 .

The punch body 5a of the punch 5 is housed in the punch holder 5b as shown in FIG.
Since it is possible to make minute movements left and right within the grooves 7a and 8a,
Even when the punch plate 10 operates in a biased manner with respect to the stripper 3, it can be smoothly moved to a position that matches the punch guide hole 71, and proper punching work can be performed.

[0028]

According to the present invention, it is possible to manufacture a product in which precise punched holes are formed without impairing the beauty of the crosspiece remaining in a thin plate-like material and its fractured surface.

Furthermore, damage such as breakage of the punch of the punching die device can be prevented.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is an exploded perspective view of a punch and a punch holder.

FIG. 3 is a perspective view of a thin plate material in which a rectangular punched hole is formed.

FIG. 4 is a sectional view of a conventional punching die device.

FIG. 5 is a diagram showing an example of deformation of punched holes.

FIG. 6 is a cross-sectional view showing a state in which the tip of the punch is broken.

[Explanation of symbols]

3. Stripper 5 Punch 12 Punch plate unit 13 Upper die set 14 Punch plate unit driving means 22 Ram 71 Punch guide hole

Claims (2)

[Claims] Claim 1: A stripper is integrally attached to the ram of a press machine via an upper die set, a punch plate unit is disposed within the stripper so as to be movable up and down, and the tip of the punch provided on the punch plate unit is attached to the stripper. A precision punching die device comprising a punch plate unit driving means that projects downward through a punch guide hole provided in the ram and causes the punch plate unit to move independently of the ram. 2. The precision machine according to claim 1, wherein the punch is composed of a punch holder and a punch body, and the punch body is capable of minute movement relative to the punch holder in a direction perpendicular to the punching direction. Punching mold equipment.