JPH0417924A - Tension die for punch press and method for punching - Google Patents

Abstract

PURPOSE:To decrease the impact of the punching work by providing the tension shaft to apply the pressure to the work and the tensile state to the inner stress of the work on the punching, which is set at the lower end part of the upper die downward to the lower die in projecting. CONSTITUTION:The work W is punched with cooperating the upper die 9 and the lower die by adopting the tension die of the punching press 1 and the punching method. The tension shaft 19 is set in projecting toward the lower die at the lower end of the upper die, and this tension shaft applies the pressure to the above work and applies the tensile state to the inner stress of the above work. Therefore, the punching force to punch the work is decreased, the impact of the punching time is decreased, so the driving component of the clutch, the bearing, etc., can be made smaller, and its manufacturing and handling can be facilitated.

Description

Detailed Description of the Invention [Purpose of the Invention (Field of Industrial Application) The present invention provides a tension mold for a punch press that can reduce the punching force when punching a workpiece in a turret punch press, for example. and regarding the punching method.

(Prior art) Conventionally, in a turret punch press, a frame is equipped with a disk-shaped upper turret that is rotatably equipped with a large number of upper molds, and a lower part that faces the upper mold and is equipped with a large number of lower molds. Equipped with a rotatable turret. The upper die and the lower die are brought directly below the striker by the rotation of the upper turret and the lower turret, and work together to punch the workpiece at this position directly below. The punching force for this purpose was determined by the net tensile strength of the workpiece, as calculated by the outer length of the upper mold x the thickness of the workpiece x the tensile strength of the workpiece.

(Problem to be solved by the invention) By the way, if this punching force is large, the impact during the punching process will be large, the mechanical strength of drive members such as clutches and bearings will increase, and the punch press will become larger. There were some problems such as doing so.

The object of the present invention is to reduce the punching force for punching a workpiece,
To provide a tension die for a punch press and a punching method, which reduce the impact of punching, reduce the size of drive members such as clutches and bearings, and are easy to manufacture and handle.

[Configuration of the Invention (Means for Solving the Problems) In order to achieve the above object, the present invention provides a punch press in which an upper die and a lower die cooperate to perform punching on a workpiece. , a tension shaft is provided at the lower end of the upper mold so as to protrude toward the lower mold, and applies pressure to the workpiece during punching to apply tension to the internal stress of the workpiece. This is a tension mold for punch presses.

In addition, when punching a workpiece by cooperation between the upper mold and the lower mold, the present invention sandwiches the workpiece between the tension shaft provided in the upper mold and the lower mold, and punches the workpiece. This is a punching method characterized by punching after applying tensile stress to a location.

(Function) By employing the tension mold and punching method of the punch press of the present invention, when the upper mold and the lower mold cooperate to perform punching on a workpiece, the lower end of the upper mold A tension shaft is provided to protrude toward the lower mold, and the tension shaft applies pressure to the workpiece and applies a tensile state to the internal stress of the workpiece, thereby reducing the punching force for punching the workpiece, The impact during punching is reduced, drive members such as clutches and bearings are miniaturized, and they are easy to manufacture and handle.

(Example) Hereinafter, an example of the present invention will be described in detail based on the drawings.

FIG. 3 shows an example of a turret punch press suitable for implementing the tension mold according to the present invention. In the figure, 25 is a frame of the turret punch press 1, and this frame 25
An upper turret 3 and a lower turret 5 are each rotatably attached to the turret. A large number of upper molds 9 are attached to the upper turret 3, and a large number of lower molds 15 are attached to the lower turret 5, respectively.

These upper and lower molds 9, 15 are brought directly below the striker 27 by the rotation of the upper and lower turrets 3.5, and are formed to cooperate with each other to perform the punching process.

Further, the frame 25 is provided with a carriage portion 35 consisting of a carriage base 29, a carriage 31, and a work clamp 33, which grips the work W and moves in the X1Y axis directions to position the work W.

FIG. 1 shows a schematic diagram of a tension mold according to an embodiment of the present invention. The upper turret 3 of the turret punch press 1 is equipped with an upper mold guide member 7 having a hollow cylindrical shape and serving as an upper mold assembly member. An upper mold 9 is mounted inside this upper mold guide member 7. In the recess 3A formed between the upper flange 7A of the upper mold guide member 7 and the upper part of the upper turret 3, a soft splint biased outward is installed in the recess 3A formed between the upper flange 7A of the upper mold guide member 7 and the upper part of the upper turret 3. 11 have been interposed.

A head 9A of the upper mold 9 is integrally fixed to the upper part of the upper mold 9 by, for example, screws or the like.

A strip spring 13 biased outward is interposed on the outer periphery of the head 9A in order to extract the upper mold 9 from the work W after punching the work W.

At the bottom of the upper mold 9, there is a tapered part 9 with a smaller external dimension.
B is provided so that it can move up and down either on the outer circumference of this tapered portion 9B or within the inner circumference of a lower flange 7B formed at the lower part of the upper mold guide member 7.

A downwardly opening hole is provided at the axis of the tapered part 9B of the upper mold 9, and a tension shaft 9 having a circular cross section is inserted into this hole and is held by an O-ring 21 for preventing removal. has been done. The tip of this tension shaft 19 protrudes toward the lower mold 5, and is provided with an appropriate protrusion dimension Δho.

The tip of the tension shaft 19 has a spherical shape with a radius of "2", and is formed so as to make surface contact with the workpiece W and to reduce impact (FIG. 2).

The lower turret 5 has a lower mold 1 corresponding to the upper mold 7.
5 are attached so that their axes are aligned. The relief portion 17 of the lower mold 15 is formed in various shapes so as not to catch a punched blank piece, for example.

A ram 23 is provided above the head 9A of the upper mold 9, and the ram 23 is moved up and down by the rotation of a crankshaft (also not shown) provided at the axial center (not shown) in the upper part of the ram 23. move.

With the above configuration, when the ram 23 is lowered, the lower end comes into contact with the head 9A of the upper mold 9, and when the ram 23 is further lowered, the upper mold 9 is moved by the biasing force of the strip spring 13. At the same time, the upper mold guide member 7 also descends against the biasing force of the soft spring 11.

At this time, as shown in FIG. 2, the tip of the tension shaft 19 protrudes beyond the lower end of the flange 7B of the upper mold guide member 7 by a dimension Δh1, for example, by several seas.
This tip comes into contact with the workpiece W first. Due to this contact, an appropriate tension is applied to the inside of the workpiece W, and a tensile stress S is generated.

And, the flange 7B of the upper mold guide member 7 is connected to the workpiece W.
After pressing to prevent escape during punching, the upper mold 9 is further lowered, and the tapered part 9B of the upper mold 9 is attached to the workpiece W.
The punching force applied by coming into contact with the workpiece W can be made smaller than the tensile strength of the workpiece W due to stress concentration or compounding, so that the workpiece W can be easily punched.

This tension shaft 19 is attached so as to be separable from the tapered portion 9B of the upper mold 9, is machined to an appropriate size, and the tapered portion 9B can be easily polished.

Note that the present invention is not limited to the above embodiments,
Other embodiments can be implemented by making appropriate design changes. For example, the tension shaft 19 may be tapered by cutting a male thread on the outside and cutting a female thread in the hole of the tapered portion 9B. It may be screwed onto the portion 9B and fixed with a pin for preventing removal.

[Effects of the Invention] As is already clear from the above description, the tension die for the punch press of the present invention allows the upper die and the lower die to cooperate when punching a workpiece. A tension shaft is provided at the lower end of the mold so as to protrude toward the lower mold, and this tension shaft applies pressure to the workpiece to impart a tensile state to the internal stress of the workpiece, thereby solving the problems of the prior art. The punching force for punching the workpiece is reduced, the impact of the punching process is reduced, drive parts such as clutches and bearings are made smaller, and they are easier to manufacture and handle. play.

[Brief explanation of drawings]

Fig. 1 is a schematic configuration diagram of a tension mold according to an embodiment of the present invention, Fig. 2 is a diagram showing how tensile stress is generated in a work by the tension shaft in Fig. 1, and Fig. 3 is a tension mold according to the present invention. 1 is a schematic configuration diagram of a suitable turret punch press in which this is implemented. 1...Turret punch press 3...Upper turret 5...Lower turret 7.
・・Upper mold guide member 7A・・Upper flange 7B・・Lower flange 9・
,・Upper mold 11・・・Soft spring 13
・Strip spring 19...Tension shaft 25...Frame representative Patent attorney Hide Kazu Miyoshi 1
...Kret punch press 3...Upper turret 5...Lower turret 7...
Upper mold guide member 7A, upper flange 7B, lower flange 9...
Upper mold 11...Soft spring 13...
・1 strip spring...tension shaft 25...frame

Claims (2)

[Claims] (1) A punch press in which an upper mold and a lower mold work together to perform punching on a workpiece, and the punch press is provided at the lower end of the upper mold so as to protrude toward the lower mold. 1. A tension mold for a punch press, comprising a tension shaft that applies pressure to the work to apply tension to the internal stress of the work. (2) When punching a workpiece in cooperation with the upper mold and lower mold, the workpiece is sandwiched between the tension shaft provided in the upper mold and the lower mold, and the workpiece is punched at the punching point. A punching method characterized by punching after applying tensile stress.