JP2766299B2 - Low noise mold - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to a low noise mold.

(Prior Art) Conventionally, for example, in a turret punch press, various measures have been taken in a machine body in order to reduce the noise of press working. However, with these various countermeasures, the device itself becomes large-scale,
At present, expensive and satisfactory noise reduction has not been achieved.

(Problems to be solved by the invention) By the way, with a press such as a turret punch press,
High noise is generated when the punch and die cooperate to punch a workpiece.However, no measures have been taken to reduce this noise until now. ,
As before, there was a problem that a mold having a conventional structure was used and noise reduction was not achieved.

SUMMARY OF THE INVENTION An object of the present invention is to provide a low-noise mold in which a pressing noise generated during punching is reduced and noise is reduced in order to improve the above-mentioned problems.

[Configuration of the invention]

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a punch body, a punch guide for guiding the punch body to reciprocate, and a stripper plate provided below the punch guide. A part of the punch body is divided, and an elastic member is interposed in the divided part to be integrated to form a low noise mold.

In the low-noise mold, it is more preferable to form the tip of the punch body at a shear angle in order to reduce noise.

(Operation) By adopting the low-noise mold of the present invention, for example, when a work is placed on a die and punching is performed on the work by cooperation of the die and the punch, the punch descends and the stripper plate is moved. Contact the surface of the work. When the punch further descends, punching is performed with the tip of the punch body hitting the work, but when the tip of the punch body hits the work, a reaction force begins to occur, and an elastic member is interposed in a divided part that divides a part of the punch body. Begins to flex. Due to the bending of the elastic member, the punching speed is reduced, the acoustic radiation energy per unit time generated when the work is sheared is reduced, and the noise generated during processing is reduced.

If the shear angle is formed at the tip of the punch main body, the punch main body gradually bites into the work, thereby further reducing noise.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a partial front sectional view of a turret in the turret punch press 1. FIG. In FIG. 1, a pair of rotatable upper and lower turrets 3 and 5 are supported by upper and lower frames (not shown).
A plurality of low noise punches 7 are mounted on the circumference of the upper turret 3. A die 9 is mounted on the circumference of the lower turret 5 at a position corresponding to the punch 7. Above the punch 7, a striker 11 that can be moved up and down by a drive device (not shown) is provided.

A hollow cylindrical punch guide 13 of the punch 7 is mounted in a stepped mounting hole 3H formed in the upper turret 3, and a stripper plate 15 is mounted below the punch guide 13 with a screw 17. A lifter spring 19 is provided between the upper flange portion 13F of the punch guide 13 and the step portion of the mounting hole 3H formed in the upper turret 3, and is constantly urged upward.

A punch body 21, which is a part of the punch body, is mounted in the punch guide 13 so as to be vertically movable. The lower end 21D (tip) of the punch body 21 is formed with a shear angle, and the upper end of the punch body 21 is provided with a collar 23 having a hollow portion.

In the hollow portion of the collar 23, a plurality of disc springs 25 as elastic members are laminated and interposed. Above the disc spring 25, a hollow punch shank 27 is provided. By passing the bolt 29 through the hollow part of the punch shank 27, the punch body 21, the collar 23 and the punch shank 27 are integrated with the bolt 29, and this is generally called a punch body. Therefore, a part of the punch body is divided, and the disc spring 25 as an elastic member is interposed in the divided portion.

A punch head 31 is provided on the upper part of the punch shank 27.
It is fixed at. Also, the flange portion of the punch head 31
A stripper spring 35 is interposed between the flange 31F and the flange 13F of the punch guide 13 so as to urge upward.

With the above configuration, the die 9 mounted on the lower turret 5
The work W is placed on the top. Next, when the striker 11 is lowered, the striker 11 comes into contact with the punch head 31. When the striker 11 is further lowered, the punch guide 13 is lifted by the lifter spring.
The lowering member 19 descends against the urging force of 19, and the stripper plate 15 provided below the punch guide 13 contacts the upper surface of the work W.

By further lowering the striker 11, the punch body 21 is lowered to the bottom dead center, and the work W is punched. At this time, when the lower end portion 21D of the punch body 21 hits the work W, a reaction force starts to be generated, and the punch shank 27
The disc spring 25 interposed between the spring 23 and the collar 23 starts to bend.
Thereby, the punching speed becomes slow, the acoustic radiation energy per unit time generated when the work W is sheared is reduced, and the noise generated during processing (during punching) can be reduced.

The elastic force stored in the disc spring 25 as an elastic member at the time of punching needs to be larger than the shearing force required for punching the workpiece W. That is, the elastic force of the disc spring 25 as an elastic member is selected so that kx> t · l · F (1).

 In the above equation (1), k: rigidity constant of the disc spring 25 x: displacement of the disc spring 25 at the time of punching t: plate thickness of the work l: circumferential length of the punching die F: tensile strength

As can be seen from the above equation (1), when the plate thickness t of the work W changes, the strength of the disc spring 25 needs to be changed, and the number of the disc springs 25 is changed according to the change in the plate thickness t. By adjusting the length, the length of the punch body can be easily adjusted by adjusting the number of disc springs 25.

Needless to say, the elastic force of the disc spring 25 is made weaker than the elastic force of the stripper spring 27.

By forming the lower end 21D of the punch body 21 at a shear angle, the lower end 21D of the punch body 21 gradually bites into the work W, so that the noise can be further reduced.

The description has been made using the disc spring 25 as the elastic member.
It is also possible to use a spring other than 25, rubber or polyurethane, etc., and when using polyurethane, by stacking a plurality of
The change in the thickness of the work W can easily correspond to the adjustment of the length of the punch body.

Therefore, by dividing a part of the punch body and interposing an elastic member in the divided portion, the noise at the time of punching can be reduced at low cost, easily and easily.

The present invention is not limited to the above-described embodiment, but can be embodied in other modes by making appropriate changes.

〔The invention's effect〕

As can be understood from the above description of the embodiment, according to the present invention, a part of the punch body constituting the punch is divided and integrated by interposing an elastic member in the divided portion. When punching a workpiece by punching, the elastic member is bent and the punching speed is reduced, so that acoustic radiation energy per unit time generated when the workpiece is sheared is reduced, and noise can be reduced.

Further, since the tip of the punch body is formed at the shear angle, the tip of the punch body gradually bites into the work, so that the noise can be further reduced.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view of a turret in a turret punch press equipped with a low noise mold according to the present invention. 3 Upper turret 5 Lower turret 7 Punch (die for low noise) 9 Die 13 Punch guide 15 Stripper plate 21 Punch body 23 Color 25 Elastic member) 27 Punch shank 31 Punch head

Claims (2)

(57) [Claims] 1. A mold comprising a punch body, a punch guide for reciprocatingly guiding the punch body, and a stripper plate provided below the punch guide.
A low-noise mold, wherein a part of the punch body is divided and integrated with an elastic member interposed between the divided parts. 2. The low-noise mold according to claim 1, wherein the tip of the punch body is formed at a shear angle.