JPH0314533B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a press mold, and particularly to a press mold that can maintain its original machining accuracy even after long-term use of the mold.

[Conventional technology]

For example, a press die as shown in Fig. 7 is used to perform shearing processes such as piercing, trimming, and blanking on a workpiece using a press machine. It will be done. The upper mold 1 is fixed to the lower surface of a slide 2 of a press machine with bolts (not shown). In this upper mold 1,
For example, a sectional die 3 for trimming the work, a pad 4 for holding down the work during trimming, and a plurality of guide posts 5 are attached. On the other hand, the lower mold 6 is fixed on the polster 7 of the press machine with a lower mold clamp 8.

A guide bush 9 is fixed to the lower mold 6 for aligning the upper and lower molds 1 and 6 in cooperation with the guide post 5 described above. It can be attached to 7.

First, the upper die 1 is gradually lowered by the slide 2, the guide post 5 is fitted into the guide bush 9, and both the dies 1 and 6 are accurately aligned. Next, insert the bolt 8 into the T groove 10 of the polster 7 and the U groove on the outer edge of the lower mold.
a, and tighten the nut 8c via the tightening seat 8b.
Tighten firmly to secure.

After accurately aligning the upper and lower dies 1 and 6 and firmly fixing them to each other, the workpiece is pressed (trimming in the example shown), which allows us to achieve high processing accuracy. It is often used for processing items that require dimensional accuracy, such as automobile parts.

[Problem that the invention seeks to solve]

However, in the case of such conventional press dies, the lower die 6 is initially aligned and fixed on the polster 7, so although high initial accuracy can be obtained, the processing accuracy decreases with use. There is a tendency to Therefore, there was a problem that the frequency of maintenance increased as the period of use became longer. This is because the molds are warped or otherwise deformed due to variations in the dynamic parallelism of the slide 2 as it descends during the press process or uneven loads when shearing the workpiece, causing the upper and lower molds 1 and 6 to sag. This is because they will not be able to fit together completely. Therefore, as the press work is repeated, cutting burrs will gradually form on the product, causing so-called star marks, etc., so release the fixation of the lower die 6 as appropriate.
It is necessary to correct the alignment.

[Means for solving problems]

This invention focuses on the above-mentioned problems and attempts to maintain the original press working accuracy without deteriorating it, by fixing the upper mold 1 to the slide 2 and
A lower die 6 is supported on a polster 7 so as to be able to move freely forward and backward and left and right along the upper surface of the bolster 7, and press work is performed while aligning the two dies by engagement with an upper guide and a lower guide. This is a press mold support method characterized by:

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on the drawings. Note that the same parts as in the prior art are given the same reference numerals.

The upper die 1 is fixed to the slide 2 of the press machine as in the conventional case. On the other hand, the lower die 6 placed on the bolster 7 of the press machine is not fixed as in the conventional case, but is supported so as to be able to move automatically forward and backward and left and right along the upper surface of the bolster. Of course, the relative positions of the upper and lower molds are determined by the guide post 5 which is the upper guide.
and the guide bush 9 which is the lower guide. 2 to 4 show the support structure of the lower die 6, where 12 is a U-groove formed on the outer edge of the lower die;
Reference numeral 10 denotes a T-groove formed in the polster 7. During die setting, align both grooves 10 and 12 and insert the fastener 1.
Insert 3. The fastener 13 (FIG. 3) inserts the head 13b of the bolt 13a into the T-groove 10, and the collared square washer 13c inserts its protruding collar 13d into the step 14a formed on the tightening seat 14 of the lower U-groove 12. The nut 13f is screwed onto the nut 13f through the spring 13e while maintaining vertical clearance, and fixed with the cotter pin 13g.

The function of the fastener 13 is only to prevent the lower mold 6 from rising together with the upper mold 1 even if the upper mold 1 and the lower mold 6 bite, and to prevent the lower mold 6 from rising with the bolster 7. It is not something that is fixed. The spring 13e and the collar 13d of the square washer prevent the fastener 13 from coming off the lower die 6 due to vibration during press working. The strength of the spring 13e is
It is sufficient that the square washer 13c can be easily lifted by hand. The lower die 6 can freely move slightly on the bolster 7 along the upper surface of the bolster 7 in front, back, right and left as shown by arrows A and B in FIG. It is guided by 9 and self-aligned, so to speak.
Since it can be easily adapted to the upper die 1, burrs will not be generated on the workpiece due to misalignment even if the press operation is repeated.

In addition, installation and removal of the fastener 13 are as follows:
Unlike the conventional complete tightening method, it can be done with one touch, which greatly reduces setup time.

Note that the upper guide and lower guide are not limited to the guide post and guide bush of the embodiment.

Other embodiments are shown in FIGS. 5 and 6.

FIG. 5 is a plan view of the floating support structure for the lower die 6 in this embodiment, and FIG. 6 is a sectional view thereof. In the figure, 20 is a butting V groove formed on the outer edge of the lower die 6;
21 is a first positioning guide pin driven into the polster 7 in order to abut against this V-groove 20;
A second guide pin 22 is also driven into the bolster 7. Reference numeral 23 designates a floating receiving portion provided on the lower die 6 to receive the second guide pin 22;
A metal bushing 24 having a through hole through which the guide pin 22 is inserted, a cushion member 25 made of an elastic material such as urethane rubber fitted around the outer circumference of the bushing 24, and a lower die 6 for pressing the bushing 24. A presser cover 26 is provided which is bolted.

When installing the mold, the lower mold 6 carried by a crane
First, the abutment V groove 20 is abutted against the first guide pin 21 for positioning, and then the bolster 7
be lowered above.

At that time, the second guide pin 22 is
Fit it into the bushing 24 of. Next, the upper mold 1 is fixed to the slide 2. During press working, self-centering is performed by the alignment means 11, as in the first embodiment. Even if a minute displacement occurs between the upper die 1 and the lower die 6 during pressing, the displacement is absorbed by the cushion member 25. Since the lower die 6 is self-centering while freely moving within the movable range of the cushion member 25, there is no risk of burrs or the like occurring on the product.

〔Effect of the invention〕

As explained above, according to this invention,
While the upper die is fixed to the press machine, the lower die is left in a free state without being forcibly fixed, and is press-formed while adjusting its position via an alignment means, making it possible to maintain the machining accuracy that was initially used. Conventional alignment maintenance is no longer required, and production efficiency can be greatly increased.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of an embodiment according to the present invention;
Figure 2 is a partial perspective view of the lower die mounting structure in Figure 1, Figure 3 is an enlarged perspective view of the fastener, Figure 4 is a sectional view showing the attachment state of the fastener in Figure 3, and Figure 5 is FIG. 6 is a plan view of another embodiment, FIG. 6 is a cross-sectional view along the line taken from FIG. 5, and FIG. 7 is a side cross-sectional view showing the support structure of a conventional press die. 1... Upper die, 2... Slide, 6... Lower die, 7
...Bolster, 5...Guide post, 9...Guide bush.

Claims (1)

[Claims] 1. An upper mold fixed to a slide, a lower mold supported on a bolster so as to be able to move forward, backward, left and right, a plurality of upper guides provided on the upper mold, and a plurality of upper guides provided on the lower mold,
A press mold characterized by comprising a plurality of lower guides that engage with the plurality of upper guides and guide the lower mold back and forth and left and right prior to processing.