JP2676986B2 - Diagonal punching die - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a press punching die, and more particularly to a diagonal punching die capable of performing highly accurate diagonal punching.

2. Description of the Related Art For example, in the case of an oblique punching process in which a punch is abutted from the vertical direction on a plate material fixed on a die in a tilted state to perform punching, the angle of the punch abutting the plate material during punching and In proportion to the magnitude of the pulling force, a component force in the direction of the lower inclination of the plate material, that is, a bending load to the lower side acts on the punch, and this force causes bending of the punch to change the die clearance. At this time, on the clearance reduction side of the plate material, secondary shear planes that are internal defects are likely to occur, and on the clearance increase side, there is a disadvantage that the fracture surface ratio increases and the product accuracy is reduced. When the amount is larger than the die clearance amount, there is a problem that the punch comes into contact with the die and the die is damaged.

Therefore, in the prior art, for example, as described in Japanese Utility Model Laid-Open No. 57-3425 (see FIG. 6), the die clearance between the punch 1 and the die 2 of the oblique punching die is determined by the punch 1
The portion where the bending occurs, that is, the lower portion (the portion indicated by the arrow A in FIG. 6) is set large by the amount of bending at the tip of the punch so that contact between the punch 1 and the die 2 is avoided. It is generally designed.

However, in the case of the above-mentioned conventional diagonal punching die, it is possible to prevent damage to the die due to contact of the punch, but since the machining accuracy is reduced by the amount of bending of the punch during punching, high precision There was a problem that processing could not be performed. Especially, the machining error is 0.1 ~ 0.3 of the plate thickness.
Fine blanking processing, which needs to be suppressed to about 10%, has not been possible with the above-mentioned oblique punching die.

Therefore, the present applicants have developed an oblique punching die capable of fine blanking and have previously proposed it (Japanese Utility Model Application No. 1-117442).

As shown in FIG. 7, this diagonal punching die is provided with a guide block 4 close to the side surface 3a of the plate pressing block 3 which guides the lifting and lowering of the punch, and the guide block 4 which receives the force in the lateral direction. A plurality of needle bearings 5 are provided between the side surface 4a and the side surface 3a of the plate pressing block 3.
The structure has a structure that disperses the lateral force by incorporating, so that the amount of bending of the die is very small, and diagonal punching can be performed while maintaining an appropriate die clearance.

However, in the case of the conventional diagonal punching die for performing the fine blanking processing described above, the material, the plate thickness, etc. are changed, and when the molding load is increased, the load in the low direction generated during punching is also increased. Guide block 4 on the lower side to increase
The deformation of the needle bearing 5 arranged between the plate holding block 3 and the plate holding block 3 becomes large (see FIG. 7). as a result,
There has been a problem that the mold clearance changes due to the increase in the molding load, and the machining error increases.

Therefore, in the case of this device, since the die clearance slightly changes by the amount of deformation of the needle bearing 5 under load, it is not suitable for high-precision punching when setting the die clearance below 10 μm. .

The present invention has been made in view of the above circumstances, and an object thereof is to provide an oblique punching die capable of performing highly accurate processing.

Means for Solving the Problems In the present invention as a means for solving the above problems, a punch is applied to a plate member fixed on a die having an inclined portion by causing the punch to act at a constant angle other than a right angle. In an oblique punching die to be carried out, a plate pressing block which moves up and down to sandwich the plate material with the die, linearly guides the lifting operation of the punch, and regulates lateral movement, and a plate pressing block outside the plate pressing block. The guide member is provided at least on the lower side surface of the inclined portion and is in contact with the surface in the lubricated state to restrict the lateral movement of the plate pressing block.

With the above-described structure, the diagonal punching die of the present invention, at the time of punching operation, the plate pressing block first descends and clamps and fixes the plate material on the inclined die, and then is guided by this plate pressing block. The punch lowers, and the tip of the punch comes into contact with the plate material. At this time, a bending load to the lower side is applied to the punch that is in contact with the inclined plate material to try to bend, but this punch is guided by the plate pressing block so as to slide linearly, and The side surface of the plate pressing block comes into surface contact with the side surface of the lower guide member of the inclined die, and the movement to the lower side is restricted.

Therefore, the punch is guided by the plate pressing block to prevent displacement and deformation, comes into surface contact with the side surface of the guide member on the lower side, and is restrained from bending to the lower side due to the bending load, and descends linearly. In addition, since either the side surface of the plate pressing block or the side surface of the guide member that are in surface contact with each other is lubricated, when the plate pressing block moves to the lower side together with the punch during punching, the side surface of the guide member is When contacting the entire surface, the movement to the lower side is reliably regulated and only smooth sliding in the linear direction is allowed, and the force is distributed over a wide area to minimize the bending of the mold. It can be suppressed. Therefore, the amount of deformation of the punch and the die can be suppressed to be extremely small, so that the die clearance can be reduced and the extremely accurate diagonal punching can be performed.

Practical Examples An embodiment of an oblique punching die according to the present invention capable of high-precision machining will be described below with reference to FIGS. 1 to 5.

The diagonal punching die 11 is a horizontal lower plate 12
And a die block 13 provided with an inclined surface 13a on which a plate material W which is a workpiece is placed, and which is installed on the upper surface of the lower plate 12, and 4 which is vertically erected on the peripheral side of the die block 13. The guide post 14 of the book, the plate pressing block 15 which is guided by the guide post 14 and is vertically movable up and down, and the guide hole 15a which is formed substantially at the center of the plate pressing block 15 and is vertically inserted. The punch 16 is driven up and down to be fixed to the lower plate 12 by abutting the lower part of the punch 16 on the outer periphery of the die block 13, and
A frame-shaped guide block 17 having working openings on both side surfaces of the inclined surface 13a except for the high side and the low side, an upper plate 18 for closing the upper portion of the frame-shaped guide block 17, and the guide posts. A push rod 19 that is vertically slidable by penetrating the upper plate 18 on an upward extension line of 14 and similarly vertically penetrates substantially the center of the upper plate 18, and the lower end of the push rod 19 of the punch 16. It has a center rod 21 connected to the upper end through a pressure receiving plate 20.

Further, the inclined surface 13a of the die block 13 is formed at an inclination of an angle θ ₁ with respect to the horizontal, and the punching is performed at a position corresponding to the guide hole 15a of the plate pressing block 15 at substantially the center of the inclined surface 13a. Equipped with shape hole 13b, die block 1
Between the punched shape hole 13b of 3 and the punch 16, a die clearance for high precision punching (about 0.1 of the plate thickness of the plate material W to be processed) is formed.
~ 0.3%) is set. A reverse press punch 22 is provided in the punched hole 13b so as to be vertically slidable, and a knockout pin 24 is connected to a lower end of the reverse press punch 22 via a pressure receiving plate 23. twenty two
An upward reverse pressing pressure is constantly applied to the shaft and is prevented from coming off by the pressure receiving plate 23. Also, slope 13a
A stopper 25 for preventing the plate material W from slipping off when it is set on the inclined surface 13a is provided on the lower side of.

In addition, the plate pressing block 15 has a die block on its lower surface.
A pressing surface 15b parallel to the inclined surface 13a of 13 is provided, and a plate pressing projection 15c is formed in an annular shape at the rim portion of the guide hole 15a opening at the approximate center of the pressing surface 15b.

Further, in the frame-shaped guide block 17, the inner side surface 17a on the higher side of the inclined surface 13a has a plate pressing block 15 corresponding thereto.
Multiple needle bearings between vertical outer surface 15d of 2
6 are provided and are in contact with each other with no gap. Further, the lower vertical side surface 17a of the inclined surface 13a almost entirely contacts the vertical side surface 15e of the plate pressing block 15 corresponding to this side surface 17a, and receives a load on the lower side generated during punching in a wide area. By doing so, the bending of the guide block 17 is prevented. Further, a large number of oil grooves 30 (see FIG. 4) are formed on the vertical side surface 17a of the guide block 17 corresponding to the lower vertical side surface 15e of the plate pressing block 15.

The oil grooves 30 are formed at equal intervals with an arbitrary inclination θ ₂ , the groove depth is D ≧ 0.5 mm, the groove width Y and the contact surface width (width of the trapezoidal portion between the grooves). The ratio with X is preferably in the range of 5 ≧ X / Y ≧ 2.

By injecting a lubricant such as grease into the oil groove 30, the plate pressing block 15 can be slid smoothly. Further, at the time of punching, the side surface 15e on the lower side of the plate pressing block 15 suppresses the galling when sliding while receiving a force to reduce the frictional resistance, and the plate pressing block 15 is bent by the bending load applied to the punch 16. Is prevented from being displaced or deformed to the lower side, and smooth ascent / descent when driven by the push rod 19 is ensured.

In FIG. 1, reference numeral 27 is a return spring loosely fitted around the push rod 19, 28 is a bearing receiver for supporting the needle bearing 26, and 29 is a bearing receiver.
A spring that elastically supports the needle bearing 26 movably via 28.

Next, the operation of this embodiment configured as described above will be described.

With the punch 16 of the oblique punching die 11 stopped at the top dead center (the state shown in the left half of FIG. 1), the plate material W, which is a workpiece, and the inclined surface 13a of the die block 13, W
The lower side is brought into contact with the stopper 25 for positioning, and is prevented from slipping off and set at a predetermined position.

Next, when the push rod 27 is pushed down, the plate pressing block 15 is pushed downward by the lower end of the push rod 27, and the plate material W on the die block 13 is slanted to the inclined surface 13a and the pressing surface 15b.
Sandwiched between. At this time, the plate pressing protrusion formed on the edge of the pressing hole 15a of the plate pressing block 15 on the pressing surface 15b side.
15c bites around the punched portion of the plate material W and regulates the plastic flow of the material around the punched portion during punching. Further, the reverse pressing punch 22 provided in the punched hole 13b of the die block 13 is pushed up by the knockout pin 24 via the pressure plate 23, and its upper end is in contact with the back surface of the plate material W. There is.

Then, when the ram of the press is stroked and the center rod 21 is lowered, the punch 16 is pressed through the pressure receiving plate 20.
Is pressed down and sandwiched between the die block 13 and the plate pressing block 15, and a predetermined portion of the plate material W whose lower surface is brought into contact with the reverse pressing punch 22 is punched.

At this time, since the plate material W to be punched is inclined, a bending load acts on the punch 16 to bend the punch 16 to the lower side.
Plate retainer block 1 that inserts into a and cards for linear descending
5, since the vertical side surface 15d on the lower side is in surface contact with the vertical side surface 17a of the guide block 17, the bending load is distributed, and the occurrence of deformation to the lower side is effectively prevented. Therefore, the change in the mold clearance is suppressed to a small level, and the mold clearance between the die block 13 and the punch 16 is 10 μm.
It can be set as follows, and processing error can be processed with high accuracy of about 0.1 to 0.3% of the plate thickness.

Further, the plate material W to be processed is an inclined surface of the die block 13.
13a and the pressing surface 15b of the plate pressing block 15, and by the plate pressing protrusion 15c formed on the pressing surface 15b,
While restricting the plastic flow of the material around the punched portion, the upper end of the forehead pressing punch 22 is brought into contact with the back surface of the plate material W, and the plate material in the part that is punched and descends is the lower end of the punch 16 and the reverse pressing punch 22. It is punched down while being clamped between the upper ends of the. Therefore, it is possible to suppress the occurrence of a fracture surface during punching and obtain a shearing surface of almost 100% of the plate thickness, so that punching with extremely high precision is achieved.

Further, in this embodiment, since a plurality of needle bearings 26 are interposed between the plate pressing block 15 and the guide block 17, the bending load applied to the guide block 17 at the time of diagonal punching is dispersed in a wide range. , The bending of the die is minimized, and therefore the amount of deformation of the punch and the die is also kept extremely small. As a result, the die clearance can be reduced and high-precision machining is possible.

In addition, the thickness of the guide block 17 on the lower side of the inclined surface 13a is taken as the x-axis, and the amount of deflection generated at the time of punching is taken as the y-axis. Comparing the case of receiving a load through the graph with a graph (see FIG. 3), the processing accuracy is improved and the load is improved because the needle bearing 26, which is easily deformed to the lower pressure part, is not used. Since they are dispersed, the thickness of the guide block 17 can be reduced.

In this embodiment, the description has been given of the case where the plurality of inclined oil grooves 30 are formed in parallel on the side surface 17a of the guide block 17 serving as the pressure receiving surface. However, as shown in FIG. Even if a plurality of inclined oil grooves 40 are formed on the side surface 17a of the guide block 17 so as to intersect each other,
Similar effects can be obtained.

EFFECTS OF THE INVENTION As described above, the diagonal punching die according to the present invention is in surface contact with the surface of the plate pressing block in the lubricated state on the outside of the plate pressing block and at least on the lower side of the inclined portion of the die. Since it is provided with a guide member that regulates lateral movement, the plate pressing block double guides the up-and-down movement of the punch, and the lubricated side surfaces are brought into contact with each other to receive a force, so that the load is dispersed and Deformation is reduced. As a result, the bending of the punch is prevented and the change of the die clearance is suppressed, so that the die clearance can be set small and highly accurate diagonal punching can be achieved. Also,
Even if the molding load is large, it is possible to perform high-precision processing, and it is possible to increase the variety of products to which diagonal punching can be applied.

[Brief description of the drawings]

1 to 4 show an embodiment of the present invention. FIG. 1 shows an oblique punching die in which the left half portion shows a state of top dead center and the right half portion shows a state of bottom dead center. A sectional front view, FIG. 2 is a plan view of FIG. 1 excluding an upper plate and a plate pressing block, and FIG. 3 is a graph showing a difference in deflection amount between a surface contact type and a needle bearing type, FIG. 4 is a diagram showing an oil groove pattern, FIG. 5 is a diagram showing another example of the oil groove pattern,
FIGS. 6 and 7 show a conventional example, FIG. 6 is a sectional front view showing a conventional diagonal punching die, and FIG. 7 is a schematic view in the case of a needle bearing type. 11 …… Slanting die, 13 …… Die block, 13a …… Sloping surface, 13b …… Punching hole, 14 …… Guide post, 15
…… Plate retainer block, 15a …… Insertion hole, 15b …… Pressing surface,
15c …… Presser protrusion, 15e …… Lower vertical side, 16 ……
Punch, 17 ... Guide block, 17a ... Vertical side, 1
9 …… Push rod, 21 …… Center rod, 22 ……
Reverse presser punch, 24 …… knockout pin, 25 …… stopper, 26 …… needle bearing, 30,40 …… oil groove, W…
... board material.

Claims (1)

(57) [Claims] 1. An oblique punching die for punching a plate material fixed on a die having an inclined portion at a constant angle other than a right angle. The plate retainer block that holds the punch in the vertical direction and linearly guides the up-and-down movement of the punch and regulates the lateral movement, and the surface outside the plate retainer block and at least on the lower side of the inclined portion of the die are in a lubricated state. And a guide member that restricts the lateral movement of the plate pressing block by making surface contact with each other.