JPH0678000U - Cushion pin in press machine - Google Patents

Abstract

(57) [Summary] [Purpose] To reduce the impact noise generated during release. [Structure] A bottomed tubular collar 6 is attached to the upper end of a cushion pin 5 with a bolt 7, and an outer diameter D is smaller than an inner diameter of the recess 6a and an inner diameter d is attached to the recess 7a.
Is smaller than the head 7a of the bolt 7 and the height H is larger than the depth of the recess 7a. A tubular cushioning member 8 made of an elastic material is fitted therein, and a blank pin is pushed up by a cushion pin after drawing. And, the sudden impact at the time of returning of the blank holder which has been jumped up is absorbed by the deformation of the buffer member 8 so that the generation of impact sound generated during this is suppressed as much as possible.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a cushion pin used in a press machine for drawing a thin steel plate.

[0002]

[Prior art]

 The pressing device used for drawing thin steel sheets is a device that lowers it further when the upper die descends, and lifts the blank holder from the lower position when the upper die ascends to form the thin steel sheet from the lower die. Cushion pins are provided.

As described above, in the conventional press devices, the push-up of the blank holder by the cushion pin after the draw forming and the return of the jumped blank holder cause them to hit each other twice forward and backward. In particular, in a press using a large number of blank holders such as a press machine for handling a large steel plate such as an automobile side panel, there is a problem that the work environment is remarkably deteriorated by the impact sound generated at this time.

[0004]

[Problems to be solved by the device]

 The present invention has been made in view of such a problem, and an object thereof is to provide an improved cushion pin that can suppress the generation of impact noise as much as possible.

[0005]

[Means for Solving the Problems]

 That is, the present invention is a cushion pin in a press device for achieving such a subject, a bottomed cylindrical collar having an open top is integrally fixed to the tip of the cushion pin by the bolt, and A tubular buffer member made of an elastic material having a length greater than the depth of the collar, an outer diameter smaller than the inner diameter of the collar, and an inner diameter smaller than the outer diameter of the head of the bolt is attached. It is designed to minimize the impact noise generated during release.

[0006]

【Example】

 Therefore, the embodiment illustrated below will be described. 1 and 2 show an example of a press machine having a die cushion locking mechanism having a cushion pin according to the present invention.

In the figure, reference numerals 1 and 2 are an upper die and a lower die for forming a thin steel plate W into a required shape, that is, a drawing die and a drawing punch in this embodiment, and on both sides of the lower die 2, A cushion pin 5 that pushes up the blank holder 9 is slidably inserted into the hole 4 of the bolster 3 and is vertically driven by a cylinder 11 on a base 12 that acts via a cushion pad 10. Has been done.

3 and 4 are enlarged views of the upper portion of the cushion pin 5. At the upper end of the cushion pin 5, a cylindrical collar 6 with a bottom that opens upward has a socket bolt 7. It is attached integrally, and the outer diameter D is smaller than the inner diameter of the recess 6a, the inner diameter d is smaller than the head 7a of the socket bolt 7, and the height H is smaller than the depth of the recess 7a. A cylindrical cushioning member 8 made of an elastic material such as hard urethane is fitted and fixed.

In the embodiment configured as described above, when the upper die 1 is moved down to perform the required forming process on the thin steel plate W, the cylinder 11 is moved above the lowering stroke of the upper die 1 accordingly. The cushion pin 5 is lowered to position the blank holder 9 so that a gap is formed between the cushion pin 5 and the lower surface of the upper mold 1.

In this state, the cushioning member 8 at the tip of the cushion pin 5 maintains its original shape as shown in FIG. 3 and has a certain gap between the cushion pin 5 and the top surface of the collar 6. It supports the blank holder 9.

Therefore, when the upper die 1 that has been subjected to the required molding is raised from this state, the cylinder 11 rapidly pushes up the cushion pin 5 through the cushion pad 10 and pushes up the blank holder 9. As described above, at this stage, the blank holder 9 is supported by the tip of the cushion pin 5 through the cushioning member 8, so that the cushion pin 5 is pushed up quickly as shown in FIG. The blank holder 9 which has been bent as described above is transmitted to the blank holder 9 and which has been jumped up and dropped by this push-up, is similarly bent to the tip of the cushion pin 5 after bending the cushioning member 8. As a result of abutting, the sudden contact between the two is weakened by the cushioning member 8, and the thin steel plate W is released from the lower mold 2 while suppressing the generation of impact noise due to the contact as much as possible. Then, a series of molding processes is completed.

[0012]

[Effect of device]

 As described above, according to the present invention, a bottomed tubular collar with an open top is fixed to the tip of the cushion pin with a bolt, and the inside of the collar has a height such that the upper end projects from the top of the collar. Since a cushioning member made of elastic material is attached, the blank pin is pushed up by the cushion pin after drawing, and the cushion pin and the blank holder are pushed back and forth twice when the blank holder is flipped up and returned. It is possible to absorb the impact over a period of time by the bending of the cushioning member, and to reduce the impact noise generated during this period as much as possible. Moreover, since this cushioning member has a tubular shape with an outer diameter smaller than the inner diameter of the collar and an inner diameter smaller than the outer diameter of the bolt head, it causes buckling when pressed by the blank holder. Without changing the shape of the cushioning member in the collar due to the gap between the two, the blank holder and the collar can be gently contacted with each other due to the repellant action at that time, and this can be achieved by long-term use. If the cushioning member is worn or damaged, it can be easily replaced by fitting the tubular cushioning member on the head of the bolt.

[Brief description of drawings]

FIG. 1 is a side view of a press machine equipped with a cushion pin according to the present invention in a molding process state.

FIG. 2 is a side view of the same apparatus in the released state.

FIG. 3 is an enlarged sectional view showing an upper portion of a cushion pin.

FIG. 4 is a cross-sectional view showing the cushion pin in a state in which a pressing force is applied.

[Explanation of symbols]

 1 Upper mold 2 Lower mold 5 Cushion pin 6 Collar 7 Socket bolt 8 Cushioning member 9 Blank holder

Claims (1)

[Scope of utility model registration request] 1. A cushion pin arranged in a pressing device to push up a blank holder in a mold releasing direction by receiving an upward biasing force, and at the tip of the cushion pin, a bottomed cylindrical collar having an open top is bolted. Is made of an elastic material having a length higher than the depth of the collar, an outer diameter smaller than the inner diameter of the collar, and an inner diameter smaller than the outer diameter of the head of the bolt. A cushion pin in a press device, wherein a cushioning member having a tubular shape is provided.