JPH0729150B2 - Lower mold clamping device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a lower mold clamping device for mounting a lower mold of a pressing device on a bolster.

[Prior Art] Conventionally, punching (piercing), edge cutting (trimming), punching (blanking) of a workpiece (workpiece)
A press device as shown in, for example, FIGS. 4 to 7 is used to perform shearing and the like.
61-49734).

In this apparatus, an upper mold 1 is fixed to a lower surface of a slide 2 of a press machine by bolts (not shown). The upper mold 1 includes a sectional die 3 for trimming a work and a pad 4 for pressing a work being trimmed. Besides, a plurality of guide posts 5 are attached.

On the other hand, in the lower mold 6, in cooperation with the guide post 5 described above,
A guide bush 7 for aligning the upper and lower molds 1 and 6 is fixed, and the lower mold 6 is attached to the bolster 8 as follows.

First, the upper mold 1 fixed to the slide 2 is gradually lowered, and the guide post 5 is fitted into the guide bush 7, so that the lower mold 6 placed on the bolster 8 is moved, and both molds 1, 6 Is accurately aligned.

Then, the head portion 9a of the tightening bolt 9 is slid along the slide groove 8a of the bolster 8, and the U groove of the lower die bottom peripheral portion 6a is formed.
It is inserted through 6b. The square washer 10 is inserted through the tightening bolt 9, the square washer 10 is placed on the bottom peripheral edge portion 6a of the lower mold 6, and the nut 11 is screwed into the threaded portion 9b of the tightening bolt 9. Since the spring 12 is interposed between the 11 and the square washer 10, the force of the spring 12 pushes the square washer 10 downward so that the lower die 6 can be movably mounted on the bolster 8. I have to.

When the press device is thus movably supported, the guide bush 7 is moved to the guide post 5 each time the press device is repeatedly used.
The lower mold 6 is moved by being guided by, and is automatically centered so that the upper mold 1 can be easily fitted. Therefore, the upper and lower dies 1 and 6 are not misaligned, and even if the pressing process is repeated, the occurrence of burrs on the work due to the misalignment can be prevented.

[Problems to be Solved by the Invention] However, in such a conventional one, when the lower mold 1 is loosely held by the tightening bolt 9 or the like, not only the tightening bolt 9 is slid but also the square washer 10 is used. Spring up against the force of the spring 12 or
It has to be attached and detached, and workability is poor. Also,
When a so-called biting phenomenon such as seizure or foreign matter biting occurs at, for example, one of the plurality of pairs of guide posts 5 and guide bushes 7, the lower die 6 is moved upward (spring 12). If the amount of compression of the guide die 5 is large, the lower die 6 is slanted and lifted upward, and a large external force acts between the guide post 5 and the guide bush 7, causing the guide bush 7 to come off or the guide post 5 to break. There is a possibility that a mold failure such as that will occur.

[Means for Solving the Problems] The present invention has been made in view of the above-mentioned conventional problems. A lower die is placed at a predetermined position on a bolster, a slide groove formed in the bolster, and the lower die. In a lower mold clamping device in which a fastener is inserted into a groove formed in the bottom peripheral edge of the lower mold, and the lower mold is mounted on the bolster, the clamp is slidable in the slide groove at the bottom. Is provided with a slide portion that is guided by the slide portion, a rod portion that is erected upward from the slide portion and that is inserted into the groove, and that a locking portion is formed on at least an upper portion of the rod portion. A washer to be placed on the upper surface of the lower die bottom peripheral edge portion, and a supporting portion for supporting the washer at a position slightly lower than the upper surface of the lower die bottom peripheral edge portion is provided in the fastening tool, and the locking is provided. Part and above A biasing member is interposed between the washer and the washer and the lower die bottom peripheral portion is provided with a cam portion that pushes up the washer upward when the tightening tool slides, and further, from the locking portion side, A lower mold that extends downward toward the washer side and that has a stopper member that stops the rising by contacting the lower mold or washer in a state where the lower mold rises by a predetermined amount against the urging force of the urging member. The feature is that it is a tightening device.

[Operation] According to such means, in order to hold the lower mold on the bolster, first, the lower mold is placed on the bolster, and the slide groove of the bolster is aligned with the groove of the lower mold. Next, the slide portion of the fastener is slid through the slide groove, and the rod portion of the fastener is inserted into the groove of the lower mold. In this case, the washer supported by the supporting portion at a position slightly lower than the lower peripheral edge portion of the lower mold is urged by the cam portion provided between the lower peripheral edge portion of the lower mold and the washer at the time of this insertion. It is pushed up against the bottom edge against the bias of the member.

Then, the lower mold is pressed by the washer by the urging force of the spring, and is loosely held on the bolster.

Therefore, it is possible to mount the lower mold on the bolster with a so-called one-touch operation by simply sliding the fastening tool, without the need to manually lift the square washer up.

By floatingly holding in this way, each time when repeatedly pressing with the press device composed of the lower mold and the upper mold,
The guide bush is guided by the guide post, and this lower die moves, and it is self-centering so that it can easily fit into the upper die, and even if the pressing process is repeated, burrs on the work caused by misalignment can occur. Occurrence will be prevented.

In addition, when a so-called biting phenomenon such as seizure or biting of foreign matter occurs at, for example, one of the plurality of pairs of guide posts or guide bushes, the lower die lifts slightly upward, but the washer or The lower die bottom edge part,
This lifting is prevented by contacting the stopper member on the locking portion side. Therefore, since the amount of upward movement of the lower mold is not large unlike in the conventional case, the lower mold does not rise obliquely and a large load does not act between the guide post and the guide bush, and the guide This prevents problems such as the bush coming off and the guide post breaking.

Incidentally, by increasing the spring constant of the biasing member and decreasing the amount of upward movement of the upper die, it is possible to prevent the guide post from being broken as described above. However, in this case, when the tightening tool is slid to press the lower die with the washer, it is difficult to move the washer upward through the cam portion against the urging force of the urging member. Therefore, if a stopper member is provided separately from the urging member as in the present invention, the spring constant of the urging member is set to a predetermined value, and the washer is applied to the urging force of the urging member when the tightening tool slides. The stopper member can prevent the lower die from rising while the lower die is biting, and thus the guide post can be prevented from being broken.

[Examples] Hereinafter, the present invention will be described based on Examples.

1 to 3 are views showing an embodiment of the present invention.

In this description, the upper mold 1, the lower mold 6, and the bolster 8 are substantially the same as the conventional ones, and thus the duplicated description is omitted.

First, the structure will be described. As in the conventional lower mold clamping device, the bolster 8 has a T-shaped slide groove 8a, and the lower peripheral part 6a of the lower mold has a U-shaped groove 6b. As shown, it is formed in four places.

Further, as shown in FIG. 2, the bolster 8 is provided with a pair of locate pins 8b, while the lower die 6 is provided with a locate U groove 6b into which the locate pin 8b is inserted.

Further, a bolt holder 21 is fixed to the side surface of the bolster 8 at a position corresponding to the slide groove 8a, as shown in FIGS. 1 and 2. This bolt holder 21
As shown in FIG. 3, a slit portion 21c is formed which is composed of a horizontal portion 21a and a vertical portion 21b and through which a fastening bolt 22 as a fastening tool is inserted. In the bolt holder 21, the vertical portion 21b is attached to the bolster 8 by a screw (not shown).
It is fixed to the side. In this fixed state, the upper surface of the horizontal portion 21a of the bolt holder 21 and the upper surface of the bolster 8 are set to be flush with each other.

The tightening bolt 22 includes a slide portion 22a slidably inserted into the slide groove 8a and a rod portion 22b protruding upward from the slide portion 22a and having a screw portion 22c formed therein. As shown in FIG. 1, the slide portion 22a has a predetermined length so that it can be inserted into the slide groove 8a even when the slide portion 22a is located at the retracted position at the right end of the slit portion 21c of the bolt holder 21 in the figure. Is set to

A holding ring 23 is fixed to the rod portion 22b of the tightening bolt 22 at a position near the upper side of the horizontal portion 21a of the bolt holder 21 with a set screw 24. Also,
A color pipe 25 is placed on the upper side of the retaining ring 23, and the color pipe 25 has an upper end as shown in FIG.
The height h is set such that 25a is located slightly below the upper surface 6c of the lower die bottom peripheral edge portion 6a.

Further, on the upper side of the color pipe 25, a washer 26 for pressing the lower die 6, a spring 27 as an urging member, and a nut 28 as an engaging portion are sequentially arranged. Thus, the spring 27 is interposed between the washer 26 and the nut 28. Also, this nut 28 is
It is non-rotatably fixed to the screw portion 22c. The downward urging force of this spring 27 is set so as to prevent the tightening bolt 22 from shifting due to vibration during production by applying a sufficient initial pressure within a range that does not impair insertion / removability. To do.

A stopper member 30 is disposed on the lower surface of the nut 28 to stop the washer 26 from rising by a predetermined amount. Specifically, the stopper member 30 is composed of a flat surface portion 30a fixed to the lower surface of the washer 26 and a cylindrical portion 30b arranged around the spring 27. As shown by the chain double-dashed line in FIG. 1, there is a space C between the lower end of the tubular portion 30b and the washer 26 in the state where the lower die 6 is tightened.
It is set to be (for example, 0.5 to 1 mm).

Furthermore, the washer 26 and the lower die bottom peripheral portion 6a are
Chamfered portions 26a and 6e are formed as cam portions, respectively. As a result, the chamfered portion 26a of the washer 26 becomes
The washer 26 is pushed upward by sliding on the chamfered portion 6e of a.

Next, the operation of the lower mold clamping device having such a configuration will be described.

When exchanging the mold, the locate pin 8b of the bolster 8 is inserted into the locate groove 6d of the lower mold 6 to place the lower mold 6 at a predetermined position on the bolster 8. In this state, the U groove 6b of the lower mold 6
And the slide groove 8a of the bolster 8 are aligned with each other.

Next, as shown by the solid line in FIG. 1, the tightening bolts 22 and the like set in the retracted position are pushed to the left side in the drawing. Then, the slide portion 22a is slid while being guided by the slide groove 8a. Then, the chamfered portion 26a of the washer 26 set to a predetermined height by the color pipe 25 comes into contact with the chamfered portion 6e of the lower die bottom peripheral edge portion 6a and slides, so that the washer 26
26 is pushed upward against the urging force of the spring 27 and placed on the upper surface portion 6c of the lower die bottom peripheral edge portion 6a (first
(See the chain double-dashed line in the figure).

As a result, the washer 26 is pushed downward by the spring 27, and the lower die 6 is pressed by the washer 26 with a predetermined pushing force to be held in a floating state.

As described above, by sliding the tightening bolt 22, the lower die 6 can be attached with one touch without the need to manually lift the square washer 10 as in the conventional case.

By thus floatingly holding the guide device, the guide bush 7 is guided by the guide post 5 and the lower mold 6 is moved and self-aligned each time the press device is repeatedly used. Therefore, even if the pressing process is repeated, the occurrence of burrs on the work due to the misalignment can be prevented.

Further, when a so-called biting phenomenon such as seizure or biting of foreign matter occurs at, for example, one of the plurality of pairs of guide posts 5 and guide bushes 7, the lower die 6 is lifted slightly upward. The washer 26 contacts the stopper member 30 on the nut 28 side to prevent the lifting. Therefore, the amount of upward movement of the lower mold 1 is not so large as in the conventional case, so that the lower mold 1 hardly tilts and is lifted upward, and the guide bush 7 is pulled out or the guide post 5 is broken. It prevents the trouble.

Incidentally, by increasing the spring constant of the spring 27 and decreasing the amount of upward movement of the lower die 6, it is conceivable to prevent the guide post 5 from being broken as described above. However, slide the tightening bolt 22
When the lower die 6 is pressed by the 26, it is difficult to raise the washer 26 against the urging force of the spring 27, and it may be difficult to secure the insertion / removal workability. Therefore, if a stopper member 30 is provided separately from the spring 27 as in the present invention, the spring constant of the spring 27 is set to a predetermined value, and the washer 26 is used as the urging force of the spring 27 when the tightening bolt 22 slides. In addition, the stopper member 30 can suppress the rising of the lower die 6 when the lower die 6 bites, so that the guide post 5 can be prevented from being broken. Become.

Further, as in this embodiment, the sliding portion 22a of the tightening bolt 22 is lengthened so that it can be inserted into the slide groove 8a of the bolster 8 even at the retracted position of the tightening bolt 22, so that the tightening at the retracted position is achieved by this insertion. Bolt 22
Since a part of the supporting force can be borne, the bolt holder 21 can be simplified.

In the above embodiment, the stopper member 30 is brought into contact with the washer 26, but the invention is not limited to this, and it goes without saying that the stopper member 30 may be brought into contact with the lower die bottom peripheral portion. Further, in the above-mentioned embodiment, the slide groove 8a has a T shape, but it is not limited to this, and it is needless to say that it may have a dovetail shape or the like.

[Effects of the Invention] As described above, according to the present invention, the operation of lifting the square washer upward unlike the prior art is not required, and the lower mold can be operated by simply sliding the fastening tool. Can be held floating on the bolster, and workability can be improved. Also, upper and lower type,
When a so-called biting phenomenon occurs, the lower die is lifted slightly upward, but the washer is prevented from coming into contact with the stopper member on the side of the locking portion to raise the lower die at an angle, and the guide bushing is prevented. It has a practically useful effect of being able to prevent slippage of the guide post and breakage of the guide post.

[Brief description of drawings]

1 to 3 are views showing an embodiment of a lower mold clamping device of the present invention. FIG. 1 is a sectional view of a main part of the device, FIG. 2 is a plan view of the device, and FIG. FIGS. 4 to 7 are views showing a conventional example, FIG. 4 is a sectional view of a press device, and FIG. 5 is a perspective view showing a slide groove of a bolster and a U-shaped groove of a lower die. FIG. 6 is a sectional view showing a clamped state of the lower die, and FIG. 7 is a perspective view showing a clamp bolt, a square washer and the like. 6 …… Lower mold, 6a …… Bottom edge 6b …… U groove, 6c …… Upper surface 6e, 26a …… Chamfer (cam part) 8 …… Bolster, 8a …… Slide groove 22 …… Tightening bolt, 22a …… Slide part 22b …… Rod part, 22c …… Screw part 25 …… Color pipe (support part) 26 …… Washer 27 …… Spring 28 …… Nut 30 …… Stopper member

Claims (1)

[Claims] 1. A lower die is placed at a predetermined position on a bolster, and a fastening tool is inserted into a slide groove formed in the bolster and a groove formed in a peripheral portion of a bottom portion of the lower die, thereby lowering the lower die. In a lower mold clamping device in which a mold is mounted on the bolster, the tightening tool has a slide part slidably guided in the slide groove in a lower part, and is erected upward from the slide part, A rod portion to be inserted into the groove is provided, a locking portion is formed at least on the upper portion of the rod portion, and a washer to be placed on the upper surface of the lower die bottom peripheral portion is inserted into the rod portion of the tightening tool to insert the washer. A supporting portion for supporting the lower die at a position slightly lower than the upper surface of the lower peripheral edge portion is provided in the tightening tool, and an urging member is interposed between the locking portion and the washer, and the washer and the lower die are provided. To the bottom edge A cam portion that pushes the washer upward when the tightening tool slides, further extends downward from the locking portion side toward the washer side, and the lower die resists the biasing force of the biasing member. A lower mold clamping device comprising a stopper member that stops the rising by contacting the lower mold or washer in a state where the lower mold is raised by a predetermined amount.