JPS6117830Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a die for a punch press, and more particularly to a center punch die for a punch press.

Center punch dies are generally used for the following purposes:

(a) If it is necessary to drill a hole with a diameter smaller than the plate thickness, it is difficult to punch it and requires drilling, so it is used to mark the center position for that purpose.

(b) Used to mark the center position for counterbore machining for countersunk screws.

(c) Used to indicate the bending position for the bending process (indicates several points).

(d) Used to indicate position for welding.

Center punch molds are used for various purposes as described above, and examples of conventional center punches include those shown below.

In other words, the punch corresponding to the die has a punch holder attached to the upper turret disk of a turret punch press, and a punch rod has a punch head at the upper end and a sharp point at the lower end in a through hole formed in the punch holder. Each of them had a punch, was urged upward, and was slidably provided.

Then, by pressing the ram of the turret punch press against the punch head and lowering it, as the punch rod descends, the punch hits the workpiece placed on the die to perform punching.

However, with such conventional center punch dies, the depth of marking on the workpiece is determined by the length between the punch head and the punch, so For workpieces, in order to make the marking depth constant, a set screw is installed in the punch head, and the overall length is shortened by turning the punch head. Adjustments such as adjusting the length and matching the size of the mark were necessary, making setup time-consuming.

Furthermore, when the adjustment is incorrect, not only is the desired mark not formed, but the punch may even be damaged due to bottoming out.

Furthermore, since there is a limit to the adjustment range, several types of molds must be prepared to accommodate a wide range of changes in plate thickness, resulting in a problem of poor versatility.

This idea was created by focusing on these conventional problems, and its purpose is to make it possible to always keep the marking depth constant even on workpieces with different thicknesses. To provide a center punch die which can be freely adjusted.

This invention will be explained below based on an embodiment shown in FIG.

First, to explain the configuration, 3 in the drawing is:
A suitable support member 5 such as a die or table that supports the workpiece W from below in the center punch mold.
It is located opposite. The punch holder 7 of the mold 3 has a substantially cylindrical shape, and has a flange portion 9 at the upper end.
Threaded portions 11 of different diameters are formed at the lower ends, a slide hole 13 is formed at the center of the flange portion 9, and a mounting hole 15 is formed at the center of the threaded portion 11, respectively. The punch holder 7 also supports an upper turret disk 1 as a support part in a punch press (not shown), for example, a turret punch press.
7 so as to be slidable in the vertical direction, and is biased upward by a coiled spring 19 interposed between the flange portion 9 and the upper turret disk 17.

The punch rod 21 of different diameters is formed of a large diameter part 23 and a small diameter part 25, and the large diameter part 23 is prevented from coming off by a retainer ring 27 attached to the flange part 9 of the punch holder 7. Further, the punch rod 21 has a punch head 29 screwed onto the upper end thereof.
A coiled spring 31 having a larger spring constant than the spring 19 is interposed between the punch head 29 and the retainer ring 27, and is biased upward.

A sharp punch tip 33 is housed in the mounting hole 15 of the punch holder 7, and is prevented from coming off by a set screw 35 screwed in from the side. A protrusion amount adjustment member 41 that allows the punch tip 33 to protrude by a desired amount t from the opening 39 of the mounting hole 15 formed in the end face 37 is adjustably screwed onto the threaded portion 11 of the punch holder 7, and is prevented from rotating with a lock nut 43. has been done.

On the other hand, a die having a flat surface is installed on the lower turret disk of a turret punch press (not shown).

Next, the operation of the embodiment having the above configuration will be explained.

For example, when punching the center position of a hole smaller than the plate thickness, first, the workpiece W is punched so that the center position is located directly below the punch tip 33.
position. Next, when the ram of a turret punch press (not shown) is pressed against the punch head 29 and lowered, the thrust force is transmitted to the punch holder 7 by the spring 31, so the punch holder 7 is lowered against the biasing force of the spring 19. Then, the punch tip 33 comes into contact with the surface of the workpiece W. After the contact, when the ram further descends together with the punch rod 21, the spring 31 compresses and transmits a larger thrust force to the punch tip 33 via the punch holder 7. punch tip 33
The end face 37 of the protrusion amount adjusting member 41 bites into the surface of the workpiece W to form a marking depth m of the mark M corresponding to the protrusion amount t. Furthermore, even if the ram descends to the bottom dead center, the punch rod 21 will
The punch holder 7 moves downward within the slide hole 13, and the excess downward movement is absorbed.

If it is desired to obtain a desired marking depth m of the mark M corresponding to the plate thickness, loosen the lock nut 43 and turn the protrusion adjustment member 41 to insert the punch tip 33 into the opening 39 of the mounting hole 15 on the end face 37. What is necessary is to match the protruding amount t of the mark M with the desired marking depth m of the mark M and lock it again with the lock nut 43.

As described above, according to the embodiment of this invention, the punch holder 7 is provided which receives thrust force through the spring 31 and accommodates the punch tip 33, and the punch holder 7 has a mounting hole formed in the end surface 37. Since the protrusion amount adjusting member 41 is provided to make the punch tip 33 protrude by the desired protrusion amount t from the opening 39 of 15, the engraving depth m of the mark M can be easily and freely adjusted by the protrusion amount adjusting member 41. This makes it possible to punch workpieces W of different thicknesses at the set marking depth m of the mark M, eliminating the need for the troublesome adjustment work required in the past, and further improving punching accuracy. be able to.

Further, since the punch holder 7 is provided which receives thrust force through the spring 31, punching can be performed with an appropriate thrust force, and there is no fear of damage to the punch due to bottoming out phenomenon. Furthermore, if the punch tip 33 is worn out,
Another advantage is that it is sufficient to simply replace the punch tip 33.

As can be understood from the above description of the embodiments, the gist of the present invention is as stated in the claims for utility model registration, and as is clear from the description, punching is performed in the present invention. The punch section for this purpose is formed at the lower end of a cylindrical punch holder that is vertically movably supported by a support section, and the protrusion amount adjustment member that is attached to the bottom of the punch holder so that the vertical position can be freely adjusted is used to The amount of protrusion of the punch portion is relatively adjusted. Further, a punch rod is supported on the punch holder via a bullet so as to be vertically movable.

Therefore, according to the present invention, the punch portion biting into the workpiece is regulated by the protrusion amount adjusting member, and the punch portion does not bite into the workpiece more than necessary. In addition, the punch holder is lowered by the punch rod via a bullet, and the punch rod does not directly lower the punch holder. The punch rod is relatively lowered. Then,
The protrusion amount adjusting member is only pressed against the workpiece by the compressive force of the bullet, and does not create impressions on the workpiece.

Note that this invention is not limited to the one embodiment described above, and can be implemented in other embodiments by making appropriate design changes.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a mold showing one embodiment of this invention. Explanation of main symbols shown in the drawings, 31...
... Spring, 7 ... Punch holder, 29 ... Punch head, 33 ... Punch tip, 41 ... Protrusion amount adjustment member.

Claims (1)

[Scope of utility model registration request] A cylindrical punch holder 7 is supported on a support portion so as to be movable up and down, and a sharp punch portion is formed at the lower end of the cylindrical punch holder 7, and the punch holder 7 is biased upward, and is supported on the punch holder 7 so as to be movable up and down. between the punch rod 21 and the punch holder 7,
A bullet is interposed to urge the punch rod 21 upward, and a protrusion amount adjustment member 41 that can relatively adjust the protrusion amount of the punch portion is attached to the lower part of the punch holder 7 so as to be vertically adjustable. A center punch mold that is characterized by