JP2002153918A - Mold clamping device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compact mold clamping device in which the energy efficiency is high, a formed stock can be easily handled, a curved stock can be easily formed, and an accessory appliance can be easily disposed on the outer side of a forming die. SOLUTION: A clamping hook 12 is arranged on an end of a split-type forming die 10 for bulging and for hydroforming, and clamping is performed by mechanically locking both ends of the forming die 10. The energy required for opening/closing operation is small, and opening/closing operation can be rapidly performed. Upper and lower surfaces of the forming die 10 are openable, and the degree of freedom in arranging the accessory appliance becomes high.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold clamping device for a mold for bulge molding and a mold for hydroforming.

[0002]

2. Description of the Related Art In bulge molding and hydroforming, a material pipe is set inside a split mold and a high-pressure liquid is injected from an end of the material pipe to perform tube expansion molding. At this time, since a mold opening force is generated in the molding die by the high-pressure liquid, it is necessary to prevent the mold opening by a mold clamping device.

In general, a large-sized hydraulic press is used as a mold clamping device for this purpose. This hydraulic press machine performs mold clamping and mold opening by lifting and lowering a large ram head, so that powerful mold clamping is possible, but there is a problem that a large amount of oil has to flow and energy efficiency is poor. . In addition, it is difficult to perform a quick mold opening operation, and the apparatus is large, such as several meters in height, and is extremely expensive.

Accordingly, the present inventors have used a rigid frame 1 having a U-shaped cross section as shown in FIG. 10 and inserted a molding die 2 therein to prevent a mold clamping device from opening. Developed earlier. Although this mold clamping device is smaller and less expensive than a hydraulic press machine, there is a problem that a molding die or a frame must be largely moved as shown by an arrow in order to handle a molded product. Further, when the shape of the molded product is largely curved, the size of the molding die becomes large, so that there is a problem that the entire frame must be enlarged. Further, since the periphery of the mold and the entire upper and lower surfaces are surrounded by the frame, the degree of freedom is greatly limited even when it is desired to arrange an accessory such as a perforated cylinder outside the mold. there were.

[0005]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems, has a small and inexpensive apparatus, can easily handle molded products, and can easily cope with curved molded products. The present invention has been made to provide a novel mold clamping device which can perform attachment and has a large degree of freedom in arranging ancillary equipment outside the molding die.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a mold clamping apparatus according to the present invention restrains an end of a divided mold in an opening direction by two or more mold hooks. It is characterized by the following. Preferably, one of the contact portions between the molding die and the mold clamping hook is provided with an inclined portion for reducing the gap between the contact portions by pushing the mold clamping hook toward the center of the molding die.
Further, it is possible to adopt a structure in which mold clamping hooks having different sizes are combined in accordance with the bias of the molded product in the molding die. Further, a structure in which a cylinder capable of generating a force equal to or more than the mold opening force of the molding die can be provided between the molding die and the mold clamping hook. Further, the mold clamping hook can be a laminated structure of steel plates.

[0007] The mold clamping device of the present invention has a structure in which the ends of the divided molds are constrained in the mold opening direction by two or more mold clamping hooks, and is therefore smaller and less expensive than a hydraulic press. . In addition, the mold can be opened only by slightly separating the mold hook from the mold, saving energy. In addition, handling of the mold is easy, and the upper and lower surfaces of the mold are open. The degree of freedom in arranging accessory devices outside the mold can be increased. Further, by changing the number and arrangement of the mold clamping hooks, it is possible to easily cope with a molding die of a curved molded product.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1 and 2 are perspective views showing a basic embodiment of the present invention. Reference numeral 10 denotes a vertically divided mold for hydroforming, and 11 denotes a mold formed therein. This is a molding cavity. Molding hooks 12 are provided at both left and right ends of the molding die 10. Each mold clamping hook 12 can be opened and closed as shown in FIG. 2 around a lower inner shaft 13. In addition, each mold clamping hook 12
Is provided with a concave portion 14 on the inner surface which is equal to the height of the mold 10;
When closed as shown in FIG. 1, between the lower jaw 15 and the upper jaw 16, the mold 10 can be restrained in the mold opening direction. In this embodiment, two mold clamping hooks 12 are arranged on each of the left and right sides, but the number thereof can be appropriately increased or decreased according to the size of the molding die 10.

FIGS. 3 and 4 are front views showing a more specific structure, in which an opening / closing cylinder 18 is mounted on left and right mold clamping hooks 12 pivotally mounted on a base 17 by a shaft 13. FIG. It is shown. In this embodiment, the mold 1
The lower half 10a is set on a base 19 on a base 17, and the upper half 10b can be raised and lowered by a lifting mechanism 20. The molding die 10 can be opened and closed with the left and right mold clamping hooks 12 open as shown by the solid line in FIG. 3, and the mold clamping hooks 12 on the left and right sides can be closed inward by the opening and closing cylinder 18 as shown by the broken lines. The mold 10 can be clamped. Reference numeral 21 denotes a shaft pushing unit that presses both ends of the material pipe, and reference numeral 22 denotes a counter cylinder that regulates a bulging amount of the material pipe.

As described above, since the mold clamping device of the present invention has a structure in which both ends of the molding die 10 are mechanically locked by the mold clamping hooks 12, the mold clamping hooks 12 can be reduced in size, and the entire device can be manufactured. It can be very small. Further, since the both ends of the molding die 10 are restrained by the clamping hooks 12, the moving distance for the clamping operation is small, the cycle time can be shortened, and the energy can be saved at the same time. Further, since the upper and lower surfaces of the molding die are open, there are many advantages such as a growth axis outside the molding die and a large degree of freedom in arranging accessories such as piercing punches.

Although the mold clamping hook 12 can be formed as an integral product, it is preferable to use a steel plate laminated structure as shown in the figure. Since such a laminated structure can be manufactured by laminating stamped steel plates, there is an advantage that the degree of freedom in shape is high, and when the mold clamping hook 12 is damaged during use, only that portion is used. Has only to be replaced, so that there is an advantage that replacement maintenance is easy.

FIG. 5 is a diagram showing an embodiment of the second aspect of the present invention. In this embodiment, an inclined portion 23 is provided at a contact portion between the molding die 10 and the mold clamping hook 12. FIG.
In this case, the inclined portion 23 is formed by slightly inclining the lower surface of the upper jaw 16 of the mold clamping hook 12 upward. If such an inclined portion 23 is provided, the upper surface of both ends of the molding die 10 is pressed downward by the inclined portion 23 by pushing the mold clamping hook 12 toward the center side of the molding die 10, and the gap between the contact portions is reduced. Can be done.

FIG. 6 is a view showing an embodiment of the fourth aspect of the present invention, in which a common base 24 and a number of small flat cylinders 25 are arranged below a molding die 10, and the mold is clamped as shown in FIG. After the hook 12 is closed, high-pressure fluid is supplied to these small flat cylinders 25, and the mold 10 is strongly clamped. In this case, the small flat cylinder 25 is
Must be able to generate a force greater than the mold opening force. If a part of the high-pressure liquid supplied to the inside of the material pipe is used as the high-pressure fluid supplied to the small flat cylinder 25, another high-pressure source is not required, and the clamping force corresponding to the mold opening force is reduced. There are advantages that can be obtained.

According to the embodiment shown in FIGS. 5 and 6, the distance between the lower jaw 15 and the upper jaw 16 of the mold clamping hook 12 can be made larger than the overall height of the molding die 10. Therefore, the upper jaw 16 of the mold clamping hook 12 does not collide with the upper end of the molding die 10 when the mold clamping hook 12 is opened and closed, so that the mold clamping hook 12 can be smoothly opened and closed.

In each of the embodiments described above, the mold 1
The size of the mold clamping hooks 12 arranged at both ends of the “0” is the same. However, when the shape of the molded product becomes complicated,
In some cases, the mold opening force generated in each part of the “0” becomes non-uniform. FIG. 7 is a view showing an embodiment of claim 3 and shows a case where a molded product having a shape deformed in the direction of the division surface of the molding die 10 is hydroformed. In this case, since a particularly large mold opening force is generated on one side of the center of the molding die 10, the mold clamping hook 12 corresponding to the portion is made larger than the other mold clamping hooks 12. As described above, it is possible to use a combination of mold clamping hooks having different sizes according to the bias of the molded product in the molding die 10. Reference numeral 21 denotes a shaft pushing means.

FIG. 8 shows an example in which the shape of a molded product is curved in a U-shape. The mold 10 for hydroforming such a curved molded article is deformed as shown.
In the conventional mold clamping device, a very large device was required to clamp such a deformed mold 10, but according to the present invention, according to the present invention, as shown in FIG.
Can be divided and arranged according to the shape of the mold 10.

In the embodiment shown in FIG. 9, the entire mold 10 and mold hook 12 are inclined obliquely with respect to the vertical plane. Thus, when one side (left side in FIG. 9) of the mold clamping hook 12 is opened, gravity acts, and the force is transmitted to the opposite mold clamping hook 12 by a chain or the like, thereby opening the opposite mold clamping hook 12. Can be assisted. Conversely, by transmitting the gravity acting when closing the right mold clamping hook 12 to the left mold clamping hook 12, the closing of the left mold clamping hook 12 can be assisted. Thus, in the embodiment shown in FIG. 9, the opening and closing of the mold clamping hook 12 can be assisted by effectively utilizing gravity.

[0018]

As described above, the mold clamping device of the present invention is designed to restrain the end of the mold in two or more mold hooks in the mold opening direction. There is little energy required for opening and closing, and opening and closing can be performed quickly. Furthermore, since the mold can be opened and closed without moving, the handling of the molded product is easy, and it is possible to easily cope with the molding of a curved molded product. In addition, since the upper and lower surfaces of the molding die can be opened, there are many advantages as compared with the prior art, for example, the degree of freedom in arranging accessory devices outside the molding die can be increased.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a clamped state of a basic embodiment of the present invention.

FIG. 2 is a perspective view showing a mold open state according to the basic embodiment of the present invention.

FIG. 3 is a front view showing a second embodiment of the present invention.

FIG. 4 is a side view showing a second embodiment of the present invention.

FIG. 5 is a front view showing a third embodiment of the present invention.

FIG. 6 is a front view showing a fourth embodiment of the present invention.

FIG. 7 is a perspective view showing a fifth embodiment of the present invention.

FIG. 8 is a perspective view showing a sixth embodiment of the present invention.

FIG. 9 is a perspective view showing a seventh embodiment of the present invention.

FIG. 10 is an explanatory diagram of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 U-shaped rigid frame in the conventional example 2 Mold in the conventional example 10 Mold in the present invention 11 Mold cavity 12 Molding hook 13 Shaft 14 Depression 15 Lower jaw 16 Upper jaw 17 Base 18 Opening / closing cylinder 19 Base Reference Signs List 20 Lifting mechanism 21 Axle pushing means 22 Counter cylinder 23 Inclined part 24 Common base 25 Small flat cylinder

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Koichi Sato 5-3 Tokai-cho, Tokai City, Aichi Prefecture Inside Nagoya Works, Nippon Steel Corporation (72) Inventor Hiroo Ishibashi 20-1 Shintomi, Futtsu City, Chiba Prefecture New (72) Inventor Koichi Hiramatsu 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation F-term (reference) 4E050 AA14

Claims (5)

[Claims] 1. A mold clamping device wherein an end of a divided mold is restrained in a mold opening direction by two or more mold clamping hooks. 2. The method according to claim 1, wherein one of the contact portions between the molding die and the mold clamping hook is provided with an inclined portion for reducing the gap between the contact portions by pushing the mold clamping hook toward the center of the molding die. The mold clamping device according to claim 1. 3. The mold clamping device according to claim 1, wherein mold clamping hooks having different sizes are combined in accordance with the bias of the molded product in the molding die. 4. The mold clamping device according to claim 1, wherein a cylinder capable of generating a force equal to or more than the mold opening force of the molding die is arranged between the molding die and the mold clamping hook. 5. The mold clamping device according to claim 1, wherein the mold clamping hook is a laminated structure of steel plates.