JPH064994Y2 - Book meat member die Forging die - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a die for forging thin-walled members, and particularly to a thin-walled member made of Al and an Al alloy and having a relatively large-area thin-walled portion. The present invention relates to a die used for die forging.

[Conventional technology]

Die forged products such as Al and Al alloys are widely used as parts for ships, vehicles, electronic devices, including aircraft parts that require specific strength, because of their higher material reliability than cast products. In recent years, there has been a strong demand for larger parts and thinner and more precise shapes.

Therefore, the main body of these die-forged products tends to be thin and have a large area, that is, the radius of the main thin-walled portion /
The thickness ratio tends to increase.

In conventional die forging, in order to meet these requirements, by increasing the dimensional accuracy of the impression of the die used, while ensuring the dimensional accuracy of the die forged product, while increasing the surface roughness of the impression, By improving the lubrication method to further reduce the frictional resistance between the die and the material to be molded in the die forging process, and to suppress the surface pressure required to mold the material to be molded, It is attempted to cope with the increase in the radius / thickness ratio.

[Problems to be solved by the device]

However, there is a practical limit to suppressing the frictional resistance between the mold and the material to be molded by improving the surface roughness of the impression of the mold and improving the lubrication method.

For this reason, when die forging a thin member having a large radius / thickness cost of the main thin portion, it is necessary to apply a large surface pressure to the main thin portion.

Then, due to the large surface pressure required for forming the main thin portion of these thin members, the impression surface portion of the mold for forming the main thin portion elastically deforms during die forging, and the main thin portion of the obtained thin member A difference in the amount of deformation occurs between the central part and the peripheral part.

Further, the difference in the amount of deformation increases as the radius / thickness ratio of the main thin portion increases, and deviates from the allowable dimensional accuracy.

Therefore, in the conventional die forging die, when die forging a thin member having a main body portion having a thin wall and a large area, after die forging, a step such as machining is added to the main thin portion of the thin member, It is necessary to have a predetermined dimensional accuracy, and the man-hours required for the production increase, which reduces the productivity.

In view of the above problems, the present invention can complement the elastic deformation of the impression surface portion of the die that molds the main thin portion of the thin member during die forging, and thus the radius / thickness ratio of the main thin portion is high. It is an object of the present invention to provide a die forging die for a thin-walled member, which enables die-forging of a thin-walled member with high accuracy.

[Means for Solving the Problems]

In order to achieve the above object, the present invention has the following configuration. That is, a die forging die for a thin-walled member according to claim 1 is a die-forging die for a thin-walled member comprising a pair of upper and lower dies (1), (2) having impressions (3), (4). In the mold, upper and lower molds (1) and (2) for molding the main thin part of the material to be molded in a pair vertically, continuously on the impression surface parts (3a) and (4a), respectively, toward the center part of the surface. The impressions (3) and (4) are provided with rising crowns (1a) and (2a), and the die forging die for a thin-walled member according to the second aspect is an impression (13), (2). 14) a pair of upper and lower insert molds (13) and (12) and a pair of upper and lower main molds having recesses (15a) and (16a) into which these upper and lower insert molds (13) and (12) are fitted. Mold
(15), in the die forging die of a thin member comprising (16), the upper and lower insert die (13), the upper and lower main die (15) of (12), (1
Regions corresponding to the impression surface portions (13a) and (14a) of the upper and lower insert molds (13) and (12) for molding the main thin portion of the material to be molded in upper and lower pairs, respectively on the upper and lower surfaces on the 6) side. The crown (11a), (12a) provided inside and continuously increasing toward the center of the crown (11a), (14a).
a) is provided.

〔Example〕

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

First Embodiment FIG. 1 is a front sectional view showing a die forging die of this embodiment.

In FIG. 1, (1) and (2) are a pair of an upper mold and a lower mold, and these upper and lower molds (1) and (2) correspond to the shape of a target thin member. Impressions (3), (4)
Is provided on each kiss surface side, and the impression (3), (4), the main surface thin part of the thin member is defined by the upper and lower pairs of the impression surface parts (3a), (4a) respectively, one point in the figure As indicated by the broken line, the impression surface (3a), a convex lens-like crown that gradually increases toward the center from the entire peripheral edge of the impression surface (3a) toward the center (4a). It is said that (1a) and (2a) are provided.

In this embodiment, the target thin member has an outer diameter D of 280 mm, as shown in FIG.
The outer peripheral surface has an annular rib portion (6) having a height h of 75 mm and a thickness tw of 3 mm, and a thickness t of 3 mm inside the rib portion (6).
While the disc material has a disk-shaped portion (5) that is the main thin portion, the pair of upper and lower molds (1) and (2) have a width and length of 420 mm and a thickness of 140 mm, respectively. Made of cubic hot work steel (JIS; SKD6) with outer dimensions to be provided with impressions (3), (4) corresponding to the shape of the disc material on each kiss surface side, and the disc material Impression surface portions (3a) and (4a) that form a pair of disc-shaped portions (5) that are the main thin-walled portions of the convex lens-shaped crowns (1a) and (2a) having a central height δ of 0.6 mm. ) Is provided.

Using a die forging die having the above-mentioned configuration, an Al alloy (JIS; alloy NO.7075 with the above-mentioned shape and dimensions, and a variation tolerance of the thickness dimension of each part is ± 0.25 mm or less by a hydraulic press. ) The disk material was hot die forged.

On the other hand, as a comparative example, a die forging die that is the same as the die forging die of the above-mentioned present embodiment, that is, a conventional die forging die, except that the crowns (1a) and (2a) are not provided. Using, the Al alloy disc material having the same shape was hot die forged under the same conditions as in this example.

With respect to each of the obtained Al alloy disc materials, the dimensions of the disc-shaped portion, which is the main thin portion, were closely examined. As a result, as shown in Table 1, the die forging die of the present example was
The difference Δε between the thickness of the central portion of the disc-shaped portion and the thickness of the outer peripheral portion was 0.18 mm at the maximum, showing good accuracy within the predetermined dimensional tolerance.

On the other hand, in the case of the die forging die of the comparative example, as shown in Table 1, the difference Δε between the central portion thickness of the disc-shaped portion and the outer peripheral portion is 1.19 mm at the maximum value, The accuracy was out of the dimensional tolerance.

Incidentally, the crown height δ of the die forging die of the present embodiment, in advance, using a pair of upper and lower flat die of the same material and the same thickness as the die forging die, the Al alloy material is simply It is set up by setting up a disc with various radius / thickness ratios, and grasping the correlation between the radius / thickness ratio and the difference in the amount of deformation between the center and outer periphery of these discs. However, this is the same diameter and thickness as the main thin-walled portion of the thin-walled member by simply upsetting Al or Al alloy material of the same material as the target thin-walled member using the same upper and lower flat molds as described above. It can also be approximated by forming a circular disc and examining the difference in the amount of deformation between the central portion and the outer peripheral portion.

However, since the difference in the amount of deformation depends on the surface roughness of the die forging die applied in the implementation, the lubrication method, the material temperature, etc., the conditions are to be checked in advance for the difference in the amount of deformation. It is desirable that the conditions be closer to the conditions for implementation.

Second Embodiment FIG. 2 is a front sectional view showing a die forging die of this embodiment.

In FIG. 2, (11) and (12) are a pair of upper insert mold and lower insert mold, and these upper and lower insert molds (11),
(12) is provided with impressions (13) and (14) corresponding to the same shape of the disk material as in the first embodiment on the kiss surface side.

(15) and (16) are a pair of an upper main mold and a lower main mold, and these upper and lower main molds (15) and (16) are upper and lower insert molds (1
The recesses (15a) and (16a) into which the (1) and (12) can be inserted and removed,
It is provided for each kissing surface side.

Then, the upper and lower main mold side of the upper and lower insert molds (11) and (12) are respectively provided with crowns (11a) and (12a), which are separately shown by a dashed line in the figure. is there.

Further, these crowns (11a), (12a), the upper and lower insert mold (11), the impression (13) of (12), (14), the disk-shaped portion (5) which is the main thin portion of the disk material. ) Is defined by a pair of top and bottom in the area corresponding to the impression surface portion (13a), (14a), the impression surface portion (13a), (14a) is provided as a substantially same shape, and the entire peripheral end portion. From the anti-impression surface (13a), (1
It is shaped like a convex lens that increases toward the 4a) side.

In this embodiment, the target thin member is the first
While using the same disc material as in the example, the upper and lower insert molds (1
1) and (12) have an outer diameter of 420 mm and a thickness of 130 mm.
Disk-shaped hot mold steel (JIS; SKD6) with outer dimensions
And these upper and lower insert molds (11), (1
Crowns (11a), (12
The height d of a) was 1.2 mm in each case.

On the other hand, the upper and lower main molds (15) and (16) for backing up these upper and lower insert molds (11) and (12) have widths and lengths of 6 respectively.
It is made of cubic hot work die steel (JIS; SKT4) having an outer dimension of 00 mm and a thickness of 270 mm, and its recess (15
The depths of a) and (16a) are the upper and lower insert molds (11) and (12) to be fitted.
It was set to be slightly shallower than each thickness.

Using the die forging die having the above configuration, the same Al alloy disc material was hot die forged under the same conditions as in the above-described first embodiment.

As shown in Table 1, the obtained Al alloy disc material has a predetermined maximum difference of 0.21 mm between the thickness of the central portion of the disc-shaped portion, which is the main thin-walled portion, and the thickness of the outer peripheral portion. It showed good accuracy within the dimensional tolerance of.

As described above, according to the die forging die of the present embodiment in which a crown is provided on the surface on the anti-impression side of the upper and lower insert dies, the main thin portion of the die is flat, for example, like an Al wheel for a vehicle. Alternatively, even for thin-walled members in which the main surface thin-walled portion is formed in a pair in the upper and lower sides and it is difficult to provide a crown on the impression surface portion, a crown corresponding to the elastic deformation of the impression surface portion in the die forging process can be easily and reliably provided. .

The crown height d of the die forging die according to the present embodiment has the same material and thickness as the die forging die in advance, and a crown having various heights is provided on the back surface side. Using a pair of flat disc-shaped upper and lower insert dies, the Al alloy material is simply upset into a disc, and the crown height d provided on the back surface of these upper and lower flat dies and the center of the disc. It is set by grasping the correlation between the difference between the outer peripheral portion and the deformation amount. This is also approximated by multiplying the crown height δ of the first embodiment described above by a coefficient of 2 to 2.5. Be searched for.

In this embodiment, the upper and lower insert molds (11), (12) crown (11a), (12a), the upper and lower insert molds (11), (12) upper and lower main mold ( 15), it is provided directly on the surface of the (16) side, instead of this, by arranging the lens-shaped spacer of the same cross-sectional shape as the crown (11a), (12a) on the surface portion, the same effect. Obtainable.

However, the outer circumference in the above table is 130 mm from the center of the disk-shaped part.
It is a portion that is closer to the outer peripheral side.

Based on the dimensional inspection result of the Al alloy disc material obtained by the die forging die of the above-mentioned first embodiment and second embodiment,
The graph of FIG. 4 shows the variation of the thickness t at the distance r in the radial direction from the center of the disc-shaped portion, which is the main thin portion, in comparison with that of the die for die of the comparative example. .

In the graph of FIG. 4, the curves plotted by ● and connected by solid lines are those of the first embodiment, and the curves plotted by ○ are those of the second embodiment and by Δ, The curves plotted and connected by dotted lines are those of the comparative example.

As shown in the graph of FIG. 4, the comparative example plotted by Δ marks, that is, the Al alloy disc material by the conventional die forging die, the thickness of the disk-shaped portion, which is the main thin portion, is smaller than that of the outer peripheral portion. The thickness greatly increased toward the center, and the thickness of the center largely deviated from the predetermined dimensional tolerance (± 0.25).

On the other hand, according to the first and second embodiments plotted by ● and ○, that is, by the die forging die according to the present invention.
In the Al alloy disc material, although the thickness of the disc-shaped portion, which is the main thin portion, tends to gradually increase from the outer peripheral portion toward the central portion, the variation is minute and the entire radial cross section. A value satisfying a predetermined dimensional tolerance is shown over the range, confirming the excellent effect of the present invention.

As described above, the die forging die according to the present invention is provided on the impression surface portions of the upper and lower molds that form the main thin portion of the thin member in the upper and lower pairs, or on the anti-impression side surface of the pair of the upper and lower insert dies. By providing each part with a crown corresponding to the elastic deformation of the impression surface part in the die forging process, the amount of elastic deformation can be complemented, and thus the area is relatively large and the radius / thickness ratio is high. Even a thin member having a main thin portion can be die-forged with high accuracy.

[Effect of device]

As described above, the die forging die for a thin-walled member according to the present invention is capable of accurately die-forging a thin-walled member having a relatively large area and a main thin portion having a high radius / thickness ratio. Therefore, it is a practical effect that a die forged product made of Al and an Al alloy can be increased in size and thinned and refined in shape without impairing productivity.

[Brief description of drawings]

FIG. 1 is a front sectional view showing a die forging die of a first embodiment of the present invention. FIG. 2 is a front sectional view showing a die forging die of a second embodiment of the present invention. FIG. 3 is a front sectional view showing a disc material according to the present invention, and FIG. 4 is a graph showing a variation in thickness of a main thin portion of the disc material according to the present invention. (1) …… upper mold, (2) …… lower mold, (1a), (1b) …… crown, (3), (4) …… impression, (3a), (4a) …… impression Face part, δ ...... Crown height, (11) …… Upper insert mold, (12) …… Lower insert mold, (11a), (12a) …… Crown, (13), (14) …… Impression, (13a), (14a) …… Impression surface, (15) …… Upper main mold, (16) …… Lower main mold, (15a), (16a) …… Recessed part, d …… Crown height.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Koichi Ozaki, Koichi Ozaki 2-183, Kitamatsuyama-cho, Seto City, Aichi Prefecture (56) References JP-A-60-108136 (JP, A) JP-A-58-77734 (JP, A) JP-A-3-77736 (JP, A)

Claims (2)

[Scope of utility model registration request] 1. A die forging die for a thin-walled member comprising a pair of upper and lower dies (1), (2) having impressions (3), (4), wherein a main thin-walled portion of a material to be molded is vertically moved. Impression surface parts (3a) and (4a) of the upper and lower molds (1) and (2) that are molded as a pair, respectively, toward the center part of the surface, the crown ((3), (4)) that continuously increases toward the (4) side. 1a), (2a) is provided, a die for die for thin-walled members. 2. A pair of upper and lower insert molds (13), (12) having impressions (13), (14), and these upper and lower insert molds (13),
In a die forging die of a thin-walled member comprising a pair of upper and lower main dies (15) and (16) having recesses (15a) into which (12) is fitted, (16a), the upper and lower insert dies Upper and lower main molds for (13) and (12)
(15), the upper and lower surfaces of the (16) side, respectively, the upper and lower insert mold (13) for molding the main thin portion of the material to be molded in a vertical pair (13a), (12a), (14a) Crowns that are provided in the areas corresponding to each of them, and that continuously increase toward the center thereof toward the anti-impression surface portions (13a) and (14a).
(11a), (12a) is provided, the die for die for thin-walled member forging.