JPH10109125A - Press die having oil supply means to punching shearing face - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a punch from being damaged due to seizure by reducing friction between a punch and a shearing face of a work in which opening is punched with the punch. SOLUTION: The press die is arranged with a punch 4 to form opening with punching a work 9, a punch support means consisting of an upper die base 1, a packing plate 2, a punch plate 3 and etc., a die 7 to support a work 9, a die support means consisting of a lower die base 8 and etc., and a stripper 7 having opening, in which the punch 4 pierces, and which presses the work 9 to the die 7. In this case, for the stripper 5, a first oil well (b) is formed around the punch 4 to supply a working oil from an outside oil supply source and a second oil well (c), which can communicate to the first oil well (b) when the punch 4 is elevated, is formed to an outer face near a tip part of the punch 4, a fixed quantity of a working oil in the second oil well (c) is supplied to a shearing face 9a of the work 9 due to the punch 4, friction is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an opening (hole) having substantially the same cross-sectional shape as a punch by punching a plate-like workpiece such as a metal plate using a punch and a die. In particular, the present invention relates to a press die having an oil supply means for punching and shearing a workpiece.

[0002]

2. Description of the Related Art For example, in an electromagnetic clutch for a car air conditioner, in order to reduce the size and weight and improve the performance, the length of the short side of a long hole formed in an armature by a press die having a punch is set to a plate thickness. In some cases. In the punch for a long hole used in such a case, the punching shear surface of the workpiece is eroded and the frictional force becomes extremely large. In general, the punch is likely to be broken, so that the life of the punch is generally shortened, and the cost of manufacturing and repairing the punch, the cost required for setting up the press machine, and the like tend to increase.

As a countermeasure against this problem in the prior art, for example, in a punch set described in Japanese Utility Model Application Laid-Open No. 58-160624, an oil reservoir is provided on a punch guide and an oil groove or a communication port is provided on a sliding surface of the punch guide. The lubricating oil is supplied to the sliding surface by making the oil reservoir communicate with the oil groove. This is to improve the method of supplying the lubricating oil to the outer peripheral portion of the punch. ,
Since it is not a method of directly lubricating the shear surface, problems of the prior art, such as burning of a punch, cannot be completely solved.

Another prior art is disclosed in Japanese Patent Application Laid-Open No. 52-444.
In the press die described in JP-B-84, an oil passage for supplying oil to a cut portion of a workpiece through the periphery or the inside of the punch is formed, but the disclosed one is a hole on the outer periphery or the inside of the punch. In this case, the processing oil is supplied to the surface of the workpiece through the through hole, and does not enable automatic oil supply to the shearing surface. Therefore, the problems of the related art cannot be sufficiently solved.

[0005] As still another conventional technique, Japanese Patent Publication No. Hei.
In the handling punch described in Japanese Patent No. 205, in order to prevent the workpiece from biting into the punch in the handling, and to facilitate the removal of the workpiece, a large number of point-like Although there is described a method in which a concave portion is provided and the concave portion is used as an oil reservoir, it is not for supplying oil to a shear surface, so that the problem of sticking of a punch cannot be solved.

As another prior art, Japanese Patent Application Laid-Open No. 55-2
In the press punching die described in Japanese Patent No. 7448, an oil reservoir for automatically applying lubricating oil to the outer periphery of the punch is provided in the stripper. In this case, the lubricating oil is applied to the outer periphery of the punch. Even if it can be applied, lubricating oil is not applied to the sheared surface of the workpiece on which the punch slides during shearing, so that the problem of sticking of the punch is still not completely solved.

As another prior art, Japanese Patent Laid-Open Publication No.
No. 527 discloses a lubricating apparatus utilizing the elasticity of a stripper. An oil drop holding member which is in contact with the punch is provided on an inner peripheral surface of a lower end of the stripper made of an elastic material provided around an outer peripheral portion of the punch. Although it is possible to apply oil to the punch with this device, it is not possible to sufficiently lubricate the sheared surface of the workpiece, so the problem of burning of the punch is still not completely solved .

[0008]

SUMMARY OF THE INVENTION The present invention addresses these problems in the prior art by directly lubricating the punched shearing surface of the workpiece in sliding contact with the punch, thereby providing friction. By suppressing the increase in force, the punched shear surface is burned to the punch by frictional heat,
An improved punching shear surface that prevents the punch from being broken easily, greatly extending the life of the punch, and reducing the cost of punch production, repair, and press setup. It is an object of the present invention to provide a press die provided with a means for supplying oil to the press.

[0009]

According to the present invention, there is provided, as a means for solving the above-mentioned problems, a press die having a means for supplying oil to a punched shearing surface as described in the claims. .

The basic feature of the present invention as set forth in claim 1 is that, in a press die including a punch, a punch supporting means, a die, a die supporting means, and a stripper, a workpiece through which the punch penetrates. For the stripper for holding,
A first oil sump is formed around the punch,
Processing oil is supplied to the first oil reservoir from an external oil supply source, and the outer surface of a portion near the tip of the punch has
A second oil reservoir that can communicate with the first oil reservoir is formed at a stroke position of the punch at a predetermined time.

As a result, the second oil sump formed in the punch is formed in the stripper near one end of the moving range of the punch with respect to the stripper, as in the case where the punch is near the top dead center position where the punch is farthest from the die. First
A certain amount of processing oil is introduced from the first sump into the second sump in communication with the second sump. Next, as in the case where the leading end of the punch is near the bottom dead center position where it enters the opening formed in the die most deeply, the second end of the punch formed near the other end of the moving range of the punch with respect to the stripper is formed. The oil sump faces the sheared surface of the opening formed in the workpiece, and an appropriate amount of processing oil in the second oil sump is automatically supplied to the sheared surface. The frictional force in the shearing surface of the workpiece in sliding contact with the punch can be suppressed from increasing, and the punched shearing surface can be prevented from seizing on the punch due to frictional heat, and the punch can be easily broken. , Greatly extend the life of the punch,
It is possible to reduce the cost of manufacturing and repairing punches and the cost of setting up a press machine.

According to the means described in claim 2, in addition to the means described in claim 1, as in the most common press mold, a pair of relatively displaced portions in the press machine is provided. Is movable, and the other part, that is, the part that supports the die and the workpiece is fixed.

According to the third aspect of the present invention, since the first oil sump formed in the stripper is covered by the oil leakage prevention plate, the processing oil supplied to the first oil sump is Except for the material supplied to the sheared surface of the workpiece through the second oil sump, it is possible to prevent the material from being leaked to the outside unnecessarily.

According to the fourth aspect of the present invention, the second
Is formed as a band-like groove over the entire outer surface of the portion near the tip of the punch, so that the oil sump communicates with the first oil sump to receive a predetermined amount of working oil, The effect of applying the processing oil to the shearing surface of the steel is performed smoothly. In addition, since the groove is provided over the entire circumference of the punch, there is no possibility that a part of the sheared surface will be poorly lubricated.

[0015]

FIG. 3 is an assembly diagram of a press die for forming a hole in a workpiece 9 by punching. The upper die 1 and the lower die 8 of the press die constitute a die set in which the positional relationship is maintained by the guide posts 15 and the guide bushes 14. The punch 4 is attached to the upper die table 1 together with the backing plate 2 while being set on the punch plate 3. The stripper 5 is hung from the upper die table 1 by a hanger bolt 10 and presses the workpiece 9 downward by the urging force of a spring 11 to thereby separate the workpiece biting the punch 4 from the punch 4. .

An oil supply hose 13 is attached to the oil supply port a of the stripper 5, and has a structure in which oil is automatically supplied from an oil supply tank 12 containing processing oil. The die 7 is set on the lower die stand 8 and is aligned with the punch 4 attached to the upper die stand 1. The location plate 16 is for accurately positioning the workpiece 9.

The upper die table 1 shown in FIG. 3 is attached to a press slide of a press machine (not shown) by bolts.
Also moves up and down together with the punch plate 3, punch 4, and stripper 5 attached thereto.

On the other hand, the lower die stand 8 is attached to a press bolster of a press machine (not shown), and is stationary together with the die 7. The process from the state in FIG. 3 in which the punch 4 is at the top dead center to the state in which the press slide descends to the state shown in FIG. 1 will be described. First, as the upper die 1 integrated with the press slide descends, The stripper 5 is pressed against the workpiece 9 by the compression force of the spring 11. When the upper mold base 1 is further lowered, the punch 4 punches out the workpiece 9 and reaches the bottom dead center, and the state shown in FIG. 1 is obtained.

When the punch 4 punches the workpiece 9, the processing oil is applied to the surface of the workpiece 9 or the cutting edge of the punch 4 even in the conventional machine. The side surface of the punch 4 and the shear surface 9 of the workpiece 9 reaching the point
Since there is no processing oil left in a, when the punch 4 returns upward, there is no lubrication between the side surface of the punch 4 and the sheared surface 9a of the workpiece 9, and the frictional resistance increases. However, since the seizure occurs due to frictional heat, there is a problem that the life of the punch 4 is shortened.

In order to deal with this problem, in the press die of the illustrated embodiment, an oil sump b (first oil sump) is formed around the punch 4 and a portion following the punch 4 as a depression of the stripper 5.
The oil reservoir b is connected from an oil supply port a to an external oil supply tank 12 by a hose 13, so that the processing oil is automatically supplied to the oil reservoir b. In order to prevent the processing oil from overflowing from the oil sump b,
An oil leakage prevention plate 6 having a hole through which the punch 4 passes is attached to the stripper 5. A groove-shaped oil sump c (second oil sump) is provided in a ring shape over the entire circumference on the side surface near the cutting blade 4a at the tip of the punch 4 itself, and the state shown in FIG. )), The processing oil is filled from the oil sump b to the oil sump c. In the state shown in FIG. 1 (near the bottom dead center), the processing oil is automatically supplied from the oil reservoir c of the punch 4 to the shear surface 9 a of the workpiece 9. In any case, since the lands other than the oil sump c, such as the cutting blade 4a of the punch 4, close the hole of the stripper 5, the processing oil does not leak directly from the oil sump b.

Therefore, when the punch 4 returns upward, the side surface of the punch 4 and the shear surface 9a
Since the processing oil that has been in the oil sump c is supplied, the frictional resistance in this portion is reduced, and the amount of generated frictional heat is reduced, so that seizure of the punch 4 on the shear surface 9a is prevented, and 4 is 4 to 4 times longer than the conventional one.
It could be extended five times. Accordingly, the number of repairs of the mold in long-term use has been greatly reduced, and the cost required for repairing the press mold has been drastically reduced.

[Brief description of the drawings]

FIG. 1 is an enlarged longitudinal sectional view showing a main part including a punch located near a bottom dead center of a press die as an embodiment of the present invention.

FIG. 2 is an enlarged longitudinal sectional view showing a main part of the press die shown in FIG. 1 including a punch at a position where a lower surface of a stripper contacts a workpiece.

FIG. 3 is a longitudinal sectional view showing the entire structure of the press die shown in FIGS. 1 and 2.

FIG. 4 shows a shape of a punch in the embodiment.
(A) is a cross-sectional view, (B) is a perspective view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Upper mold stand 2 ... Backing plate 3 ... Punch plate 4 ... Punch 4a ... Cutting blade 5 ... Stripper 6 ... Oil leakage prevention plate 7 ... Die 8 ... Lower mold stand 9 ... Work material 9a ... Shear surface 10 ... Hanger bolt DESCRIPTION OF SYMBOLS 11 ... Spring 12 ... Oil supply tank 13 ... Oil supply hose 14 ... Guide bush 15 ... Guide post 16 ... Location plate a ... Oil supply port b ... 1st oil sump c ... 2nd oil sump

Claims (4)

[Claims] 1. A punch for forming an opening in a workpiece by punching the workpiece, and a base of the punch attached to and supported on one of a pair of relatively displaceable parts of a press machine. A die having an opening for receiving the tip of the punch for supporting the workpiece and cooperating with the punch to form the opening in the workpiece; Die support means for attaching and supporting the die to the other part of the pair of parts which are displaced in a horizontal direction, and an opening through which the punch penetrates, and the workpiece to the die when punching is performed. A first oil sump is formed around the punch penetrating the stripper, and processing oil is supplied from an oil supply source. A second oil sump is formed on an outer surface of a portion near a tip end of the punch, and the second oil sump is formed by the first oil sump near one end of a moving range of the punch with respect to the stripper. The processing oil is introduced from the first oil sump into the second oil sump in communication with the sump, and the second oil sump is placed near the other end of the range of movement of the punch with respect to the stripper. A means for supplying the processing oil of the second oil sump to the shearing surface facing the shearing surface of the opening formed in the processing material, wherein the means for supplying oil to the punching shearing surface is provided. Press mold having 2. The press machine according to claim 1, wherein said one of said pair of relatively displaceable parts of said press machine is movable, and said other part is fixed. The described press mold. 3. The press die according to claim 1, wherein the first oil sump is covered by an oil leakage prevention plate. 4. The punch according to claim 1, wherein the second oil reservoir is formed by a groove formed over the entire outer surface of a portion near the tip of the punch. Press mold.