JPS642454B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a press mold for cushion drawing provided with a device for reducing noise.

As a conventional press type for cushion draw,
For example, there is one shown in FIG.

Reference numeral 1 denotes a punch fixed to the bolster of a press machine (not shown) via a lower holder 2, which is movable relative to the punch 1, and is pushed up by a cushion pin 3 before processing. The lower mold A together with the blank holder 4 and the lower holder 2
It consists of

A die 5 is attached to a slide of a press (not shown) via an upper holder 6 and forms a workpiece 7 in cooperation with a lower mold A, and together with the upper holder 6 constitutes an upper mold B.

Now, when the work 7 is placed on the lower die A and the die 5 is lowered, the protrusion 5a of the die 5 will first touch the work 7.
When the upper die B is further lowered, the protrusion 5a and the blank holder 4 descend to a lower level than the upper surface of the punch 1 while pressing the workpiece 7 and pushing the cushion pin downward. The state shown in the figure is reached, and the workpiece 7 is formed.

However, in such a conventional press die for cushion drawing, the slide descends at a certain speed, so the die 5 fixed to the slide collides with the blank holder 4 via the workpiece 7, resulting in a fairly large There was a problem in that the sound of metal collision caused a deterioration of the working environment.

This invention was made by focusing on such conventional problems, and by creating a structure in which the blank holder is lowered at a speed slower than the lowering speed of the upper mold before machining the workpiece, the above problems are solved. The purpose is to resolve the issue.

The present invention will be explained below based on the drawings.

FIGS. 3 to 6 are diagrams showing one embodiment of the present invention.

Note that although the shape of the press mold itself in these drawings is slightly different from the conventional one, the substantial structure is the same.

First, to explain the configuration, 8 is a die attached to the slide of a press machine (not shown) via an upper holder 8a, 9 is a drive cam attached to the upper holder 8a, and the lower end is θ ₁ with respect to the horizontal plane. It has a slope 9a formed at an angle of.

10 is a lower holder 1 attached to the press machine bolster (not shown)
This punch 10 is fixed through the punch 1
A blank holder 13 is provided to be movable relative to the blank holder 13 and is pushed up by a cushion pin 12 before processing, and the lower holder 11 constitutes a lower mold D.

Further, a cam receiving portion 14 is protruded from the blank holder 13, and the cam receiving portion has a slope 14a formed at an angle of θ ₂ with respect to the horizontal plane. Here, the angles have a relationship of θ ₁ >θ ₂ .

Reference numeral 15 denotes a post erected on the lower holder 11, and a sliding housing 17 in which a sliding cam 16 is slidably inserted in the left-right direction is provided at the upper end. Reference numeral 18 denotes a wear plate provided within the sliding housing 17 on the sliding surface with the sliding cam 16.

A motion transmission device is interposed between the upper die C and the blank holder 13 by the sliding cam 16, the driving cam 9 that engages with the sliding cam 16, the post 15 provided with the cam receiving portion 14, and the sliding housing 17. configured.

Also, the slope 9a of the drive cam 9 of the sliding cam 16
A slope 16a having the same angle θ ₁ as the slope 9a is formed on the side corresponding to the slope 9a to constitute interlocking means, and a slope 16a having the same angle θ ₂ as the slope 14a is formed on the side of the cam receiving portion 14 corresponding to the slope 14a. A slope 16b is formed to constitute a transmission means, and a slope 14a
and the slope 16b are in contact with each other before processing.

Furthermore, a motion transmission device is constituted by the interlocking means and the transmission means.

19 indicates a workpiece.

Next, the action will be explained.

FIG. 3 shows the mutual relationship between the die 8, the drive cam 9, and each part of the lower mold D when the slide (not shown) is near the top dead center.

Now set the workpiece 19 on the lower die D, and then move the workpiece 19 onto the upper die C.
When the slider moves downward at a speed _V1 , the slope 9a comes into contact with the slope 16a and pushes the sliding cam 16 to the left in the drawing at a speed _V2 . At this time, when the angle θ ₁ is larger than 45°, the speed V ₂ is smaller than V ₁ .

Next, the sliding cam 16 pushed at the speed V ₂ is in sliding contact with its slope 16b and the slope 14a of the cam receiving part 14 as described above, so it immediately moves through the cam receiving part 14. Blank holder 13 speed V ₃
will push it downward. (See Figure 5) The speed V ₃ at this time is smaller than the speed V ₂ when θ ₂ is less than 45°. That is, the downward motion of the die 8 is transmitted to the blank holder 13 at a reduced speed.

Therefore, the blank holder 13 descends at a lower speed than the descending speed of the upper mold C.

Further, when the upper mold C further descends and the slope 9a of the drive cam 9 comes below the sliding housing 17, the die 8
catches up with the blank holder 13, which is already descending at a speed of _V3 , collides with the workpiece 19, and continues to descend while pushing the cushion pin 12 downward. When the upper mold C descends to a certain extent, the slope 9a of the drive cam 9 comes off the slope 16a of the sliding cam 16. Therefore, the blank holder 13 descends at the same speed as the upper mold C, reaches near the bottom dead center of the slide (not shown), and enters the state shown in FIG. 6, where the workpiece 19 is processed.

The collision sound between the die 8 and the blank holder 13 at this time is much smaller than when the blank holder is in a stationary state as in the conventional example, because the relative speed of the die 8 with respect to the blank holder 13 is small.

Next, when the machining is finished and the slide rises, the blank holder 13 also rises, and accordingly the cam receiving part 14 also rises and comes into contact with the sliding cam 16, pushing it back to the right in the drawing to the initial state.

As explained above, according to this invention,
Since the blank holder is lowered at a lower speed than the lowering speed of the upper die prior to processing, a sound-dampening effect can be obtained to buffer the large impact noise between metals during workpiece forming.

[Brief explanation of the drawing]

1 and 2 are cross-sectional explanatory views of a conventional cushion draw press mold, FIG. 3 is a cross-sectional view of main parts of an embodiment according to the present invention, and FIG. The A view and FIGS. 5 and 6 are partial explanatory diagrams showing the operating point of the embodiment. A, C... Upper die, 7, 19... Workpiece, 4, 13...
Blank holder, {9... drive cam, 9a... slope,
16...Sliding cam, 16a...Slope} Interlocking means, {1
6...Sliding cam, 16b...Slope, 14...Cam receiving part,
14a...Slope}Transmission means.

Claims (1)

[Claims] 1. A drive cam fixed to the upper mold and having a slope,
a sliding housing member fixed to the lower mold; a first slope that is horizontally slidable within the sliding housing member; a first slope that engages with the slope at one end; and a first slope that engages with the slope at one end; second to
and a cam receiver fixed to the blank holder and having a slope that engages with the second slope, until the blank holder clamps the workpiece. A press mold for a cushion draw, comprising a motion transmission device configured to reduce the descending speed of the blank holder in conjunction with the descending motion of the upper mold, thereby imparting a descending motion to the blank holder.