JP2577030B2 - Forging equipment - Google Patents

Description

The present invention relates to a forging device for semi-hermetic die forging, in particular,
By applying to a forged product that has a part that does not require post-processing and a part that does not need it, the dimensions of the burrs generated in each part of the forged product are adjusted properly, and the material yield is improved, The present invention relates to a forging device that facilitates trimming of generated burrs.

(Prior Art) FIG. 7 shows an example of a forging device of this kind that has been widely and conventionally used.

This is one in which required forming surfaces 3 and 4 are formed on each of an upper die 1 and a lower side 2 facing each other. In such a forging apparatus, a material W preliminarily processed in a rough land process as a previous process is used. Is pressed and constrained between the respective molding surfaces based on the lowering of the upper mold 1 as shown in FIG. 7 (a), so that each of the molding surfaces 3, 3 is formed as shown in FIG. 7 (b). 4. It is possible to provide a forged product having a predetermined shape exactly following the shape of the forged product.

Here, the lower limit position of the upper mold 1 is determined such that a predetermined gap C exists between the respective parting surfaces 5 and 6 of the upper and lower molds 1 and 2 at the end of molding of the material W. The gap C
By allowing the generation of burrs F therefrom,
It functions to suck the variation in the volume of the material W.

(Problems to be Solved by the Invention) However, in the prior art, in the initial stage of forming the material W, as shown in FIG.
Due to the fact that the gap C ₁ between the mold cutting surfaces 5 and 6 of the second mold 2 is considerably large, when forming the mold, the mold holes or the mold grooves 7 and 8 of the respective molds 1 and 2 are more sufficiently filled with the material W First, the generation of the burrs F starts, and the mold holes or the mold grooves 7, 8 are filled only when the flow resistance of the material W in the burrs becomes extremely high at the end of molding. Therefore, there is a problem in that the volume of the portion that eventually becomes the burrs F is large and the material yield is poor.

For this reason, the applicant has previously proposed, as Japanese Patent Application No. 61-71716, a forging device for minimizing the volume of a flash.

In this forging device, one of the upper and lower dies is composed of an inner punch that presses and restrains the center of the material and an outer punch that presses and restrains the edge of the material. It is slidable with respect to the punch, and it is urged toward the other mold by elastic means, and the spring force of the elastic means is used to separate the outer punch from the other mold at the end of molding on the material. The size is acceptable.

According to such an apparatus, during the period from the start of molding to the final stage of the material, the material is subjected to a substantially closed forging in a closed molding space, where the molding is performed. Since burrs occur only at the end of the period, the volume of the burrs can be significantly reduced as compared with the forging apparatus described above, and the material yield can be sufficiently improved.

However, with this forging device, the size of the burrs generated over the entire circumference of the forged product, particularly the thickness, is too small, so that it is difficult to remove the burrs in the trimming process following the forging, and it is difficult to perform one-time shearing. The problem is that it cannot be removed enough,
In particular, in one forged product, a part that does not require post-processing following trimming and straightening, in other words, a part that finishes all processing by trimming, straightening, etc., and cutting, cutting, When both parts requiring processing such as grinding are present, it is important to completely treat burrs in parts not requiring post-processing.

The present invention has been made in view of such a problem of the prior art, and is based on a forging apparatus described in Japanese Utility Model Application No. 61-71716, and a part that requires post-processing and a part that does not require post-processing. The present invention is to provide a forging device that effectively improves the material yield and facilitates the deburring operation by generating burrs of appropriate dimensions in each part of the forged product having:

(Means for Solving the Problems) A forging apparatus according to the present invention includes: an inner punch for pressing and restraining at least one of an intermediate portion of a material in a width direction and a length direction; And an outer punch for pressing and restraining the outer punch. The outer punch is slidable with respect to the inter-punch, and is urged toward the other mold by elastic means. The spring force of the means should be large enough to allow the outer punch to be separated from the other mold at the end of the forming of the material, and the forged product should be used to form the part that does not require post-processing. In addition, at least one molding surface of the outer punch and the other mold facing the outer punch is provided with a burr forming portion adjacent to the mold cutting surface.

(Operation) In the forging device of the present invention, when forming a material,
For example, by lowering the upper die composed of the inner punch and the outer punch, the outer punch comes into close contact with the lower die under the action of the elastic means prior to the start of molding of the material, and the material is molded. From the start to the end of the process, a substantially closed forging is performed in the closed molding space, so that the generation of burrs to the side of the molding space is reliably prevented during that time. Will be.

On the other hand, at the end of the molding, after the molding spaces surrounded by the respective molding surfaces are completely filled with the material, the outer punch is moved by the elastic means based on the rise in the internal pressure of the molding space. Since it is relatively raised from the lower mold against the pressure, this makes it possible for the first time to generate burrs to the side of the molding space, and the burrs are formed after forming a forged product of a predetermined shape. Since it is formed only of the excess portion, the size becomes extremely small.

By the way, the forged product formed in this way has other sharable burrs formed by the burrs formed in the forming space on its side only in a portion that does not require the back-down. Therefore, deburring in the trimming step can be performed extremely easily by one burr shearing.

Therefore, in this forging apparatus, by the end of the forging process such as trimming and straightening subsequent to the forging, a flash having an appropriate size that can be sheared is generated in the forged product part that completes processing of the forged product by the action of the flash forming part. While
After the forging process, other forged parts that require post-processing such as cutting and grinding, in other words, forged parts where burrs are inevitably removed by post-processing without trimming. Requires only post-processing by generating only small-sized burrs that protrude from the space between the outer punch and the lower die to the side of the molding space without generating burrs due to burrs. The material yield at the part can be significantly improved, and at the same time, the deburring work at the part that does not require post-processing can be made extremely easy.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a longitudinal sectional view of an essential part showing an embodiment of the present invention, in which 11 denotes an upper die, and 12 denotes a lower die.

This is a cross section of a forging device P used for forming a forged product P to which a flash M is attached, as shown in a bottom view in FIG. In such a forged product P, the connection boss portion B and the I section I of the crankshaft are connected to the crankshaft by ending the forging process, in other words, by ending trimming and straightening following forging. While the processing can be completed, the connection boss portion A to the piston needs to be finished to a required shape by post-processing such as cutting, cutting, and grinding after the forging process. Therefore, in the forging device portion shown in FIG.
While the mold structure is used to ensure simple and quick deburring work, the forging device that is responsible for forming forged parts that require post-processing, as shown in FIG. And a type structure that allows only

Here, in the forging device portion shown in FIG.
The inner punch 13 presses and restrains an intermediate portion of the material W, for example, a central portion in the width direction and the length direction, and corresponds to a product contour which presses and restrains an edge portion of the material W, for example, a peripheral portion thereof. And an outer punch 14 having a shape.
While holding the outer punch 14 in the holder block.
Under the guidance of the lower holder 17 fixed to 15, the inner punch
13 can be slid up and down.

Here, a disc spring 18 as an example of elastic means is interposed between the outer punch 14 and the holder block 15 in the lower holder, and the disc spring 18
To the lower mold 12. As a result, the outer punch 14 is usually provided with the outward flange 14 provided there.
The inner punch 13 protrudes downward with respect to the inner punch 13 to a position where the a and the inward flange 17a formed on the lower holder 17 come into contact with each other.

Here, the inner punch 13 and the outer punch
The upper die 11 made of 14 has a molding surface 19 of a required shape composed of the lower end surface of the inner punch 13 and the inclined inner peripheral surface of the lower end of the outer punch.

On the other hand, the die as the lower die 12 is formed by depressing from the mold surface 20 and is also provided with a molding surface 21 having a required shape, and each of the molding surfaces 21 adjacent to the mold surface 20 is formed. The end portion is provided with a burr forming portion 22 formed in a stepwise manner in a direction in which the forming surface 21 expands, and these burr forming portions 22 substantially constitute a part of the forming surface 21.

In the forging apparatus portion configured as described above, under the state where the pre-processed material W is positioned and arranged on the lower mold 12, by operating the press ram 16 to lower the upper mold 11, initially, Under the action of the disc spring 18, the outer punch 14 protruding downward from the inner punch 13 contacts the material W to press and restrain the peripheral edge thereof, and
12 to form a closed molding space, then
The material W existing in the molding space
Press and restrain the central part of

As a result, the inner punch 13 is provided in the sealing forming space formed by the outer punch being in close contact with the lower mold 12, as shown in FIG. 22 is completely filled with the material W, and as it descends, the respective mold holes or grooves in the molding space are also gradually filled.

Then, at the end of molding, when the molding space is completely filled with the material W, the internal pressure of the molding space is significantly increased, and the material W filling the space is formed on the inclined inner peripheral surface at the lower end of the outer punch. This exerts a pushing-up force that overcomes the spring force of the disc spring 18, and as a result, slightly before the inner punch 3 reaches its lower limit position, the outer punch 14 Since the material W is pushed up from the lower mold 12 to a position where the pushing force is balanced, as shown in FIG.
From between them, they are pushed outward as burrs F.

Here, the burrs F generated between the lower mold 12 and the lower end surface of the outer punch 14 are advantageous in terms of yield because they have a very small volume as described above. Of the molding surface 21, the burrs 22 formed on the molding surface 21 as if they were part of a forged product.
Makes the deburring action very easy and reliable under a preselected appropriate thickness.

Therefore, after the forming of the material W is completed as described above, the forged product P as a product is taken out of the mold, and as shown in FIG. By trimming so as to cut off along the peripheral surface of the forged product P, both the burrs M and F can be easily removed from the forged product P. Simple and quick operation can be realized.

Note that, in the above-described embodiment, in addition to providing the flash forming portion only on the outer punch 14, it is also possible to provide the flash forming portion on both the lower mold 12 and the outer punch 14. However, the same function and effect can be obtained.

In addition, here, in the forged product portion to be subjected to post-processing, in other words, in the forged product P shown in FIG. 2, in the connection boss portion A where the flash M does not adhere, the flash generated there is easy to deburr. It does not matter whether or not the burr is completely removed by post-processing.From the viewpoint of removing the burr, even if the burr has a large volume as in the prior art, No problem,
From the viewpoint of material yield, it is preferable that the material be as small as possible.

Therefore, as shown in FIG. 3, in the forging device portion for forming the forged product portion requiring post-processing, the applicant has previously filed the actual application by omitting the burr forming portion 22 from the forging device portion described above. As with the forging apparatus disclosed in Japanese Patent Application Laid-Open No. 61-71716, it is preferable to use a mold structure that generates only a small volume of burrs F.

Thus, according to the forging device as described above, the forged part that does not require post-processing is a flash M part,
Easy and quick deburring work, and
In a forged part requiring post-processing, the yield of material can be advantageously improved by the generation of the small-volume burrs F.

FIG. 5 is a bottom view illustrating an outer punch 14 of another forging device. In this outer punch 14, in order to secure a simple and quick deburring operation in a forged part that does not require post-processing, In the forging part, VI-
As is clear from FIG. 6 showing a cross section along the line VI, the upper mold
A flash forming part 25 adjacent to the parting surface 24 is provided on the inclined inner peripheral surface 23 of the outer punch 14, which forms a part of the forming surface 19 of the eleventh embodiment. On the other hand, in the forming part of the forged part requiring post-processing, only the small-volume burrs F can be generated by omitting the burrs 25 as described with reference to FIG.

It goes without saying that the forging device configured as described above can also provide the same operational effects as those of the above-described embodiment.

Although the present invention has been described based on the illustrated example, the latter forging device can also generate a so-called burring at a forged part requiring post-processing.

(Effects of the Invention) Therefore, according to the present invention, the volume of burrs generated in a portion of the forged product that does not require post-processing is selected to be appropriate by the action of the burrs formed on the forming surface. As a result, the material yield can be sufficiently improved, and the deburring operation can be performed extremely easily and quickly. In addition, the forged products that require post-processing are deburred. Further improvement in material yield can be achieved by generating only burrs of such a small volume that operation becomes difficult.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view illustrating a part of a forging apparatus according to the present invention, FIG. 2 is a bottom view illustrating a forged product with burrs, and FIG. 3 is a longitudinal sectional view illustrating another part of the forging apparatus. Fig. 4 is an enlarged cross-sectional view of a flash adhering to a portion that does not require post-processing, Fig. 5 is a bottom view illustrating an outer punch of another forging device, and Fig. 6 is a line VI-VI in Fig. 5. FIG. 7 is a longitudinal sectional view showing a conventional example. 11… Upper die, 12… Lower die 13… Inner punch, 14… Outer punch 18… Disc spring, 19, 20… Molding surface 20, 24… Molding surface, 22, 25… Burr Forming part W …… Work

Claims (1)

(57) [Claims] 1. A forging device comprising an upper mold (11) and a lower side (12), and presses and restrains a material between respective molding surfaces of the molds to produce a forged product of a predetermined shape. Press one of the upper and lower molds and press the middle part of the material (W).
Press the inner punch (13) to restrain and press the edge of the material.
An outer punch (14) for restraining the outer punch. The outer punch is slidable with respect to the inner punch, and is urged toward the other mold by an elastic means (18). In the final stage of forming the material, the outer punch is set to a size that allows the outer punch to be separated from the other die, and the forged product is used for forming a portion that does not require post-processing. A forging device comprising at least one forming surface (19, 21) of the outer punch (14) and the other mold provided with a burr forming portion (22, 25) adjacent to the parting surface (24, 20). .