JPH1110269A - Form rolling device for headed shaft shaped products - Google Patents

Abstract

PROBLEM TO BE SOLVED: To satisfactorily form a reduced part without causing an unnecessary stepped part on a rear face of the headed part in forming a reduced part under a head of a stock having a head part to one end of a shaft part. SOLUTION: A projecting line 4, which forms a reduced part under a head of a stock by gradually protruding from an end part X' of a rolling start side to an end part X' of a form rolling completion side, is provided at a side part of a stock head part side in working faces of a pair of flat dies 2, in which faces facing each other are made to a working face. A prescribed range X1 from the end part X' of a rolling start side of a face facing a head rear face of the stock in the flat die 2 is made into a tapered face 5c, which erects from a position lower than a form rolling completion side part of the face 5 and presses up a head rear face of the stock to be form rolled.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for forming various types of metal shaft products, and more particularly to an apparatus for rolling a shaft product having a head to a lower part of a neck.

[0002]

2. Description of the Related Art Rolling devices are used for processing various axial products such as processing a rod member having a spherical head used for a ball joint and forming a thread groove of a bolt. As a rolling device, for example, JP-B-63-5
As disclosed in Japanese Patent No. 7135, an axial material is sandwiched between a pair of elongated flat dies each having a surface facing each other as a processing surface, and in this state, these dies are relatively moved in the longitudinal direction. It is known that a material is rolled between both dies to plastically deform a peripheral surface of the material into a predetermined shape in accordance with irregularities provided on a processing surface of the die.

[0003] Using this rolling device, as shown in Fig. 13, a material A having a head A2 at one end of a shaft portion A1 is used to form a head B2 at one end of a shaft portion B1. And a reduced diameter portion B3 just below the head B2 at the so-called lower part of the neck.
When manufacturing the product B having the following formula, as shown in FIG.
The processing surface of the pair of flat dies C, C has a head A2 of the material A.
Along the side where the is located, gradually protrudes from the end C1 on the rolling start side to the end C2 on the rolling end side, and finally has a cross-sectional shape corresponding to the reduced diameter portion B3 of the product B. Ridge C3 is provided.

The processing surfaces of the pair of flat dies C, C are opposed to each other, and the shaft A1 of the material A is sandwiched between the ends C1, C1 on the rolling start side of the two dies C, C. ,
From this state, one of the dies C is relatively moved in the longitudinal direction with respect to the other die C while sandwiching the material A, and the material A is rolled between the two dies C. The lower part of the neck of A is reduced in diameter by the ridges C3 and C3,
From the ends C2 and C2 of the two dies C and C on the rolling end side, the product B having the reduced diameter portion B3 of a predetermined shape is discharged.

[0005]

When the flat product C having the head is manufactured by rolling using the flat dies C, C, the following problems occur.

That is, as shown in FIG.
When the ridges C3 and C3 of the material bite into the lower part of the neck of the material A, and the bite amount gradually increases, the volume dislocation of the material from the lower part of the neck to the upper and lower as shown by arrows a and b occurs. However, of these, the volume dislocation a toward the head A2 causes the head A2 to gradually move to the upper surface C of the dice C, C.
4, C4, and the lower surface of the material head A2 and the upper surfaces C4, D4 of the dies C, C generated by the lifting.
As shown by the symbol y, the material subjected to the volume dislocation protrudes into the gaps x and x between C4 and C4. Therefore, FIG.
As shown in the figure, when a reduced diameter portion B3 of a predetermined shape is formed at the lower part of the neck as the final product B, the reduced diameter portion B3 and the head B2 are formed.
The gap x caused by the above-mentioned lifting
Is generated, and the lower part of the neck is not formed into a predetermined shape.

Therefore, conventionally, such a reduced diameter portion has been formed by cutting, but in this case, it takes a long time to form, and it is necessary to treat chips, and in the case of rolling, There is a problem that productivity is worse than that.

[0008] In addition to the forming of the diameter-reduced portion B3, a molding process or a burnishing process for finishing the head portion B2 may be performed. When the head B2 rises, the positional relationship between the reduced diameter portion B3 and the head B2 becomes inconsistent, so that the flat die for forming the reduced diameter portion and the flat die for processing the head are integrated into two. It becomes difficult to continuously process the part, and the reduced diameter part B
After the molding of No. 3, the head B2 must be processed again using another rolling device.

Therefore, the present invention can form a reduced diameter portion in a lower part of a neck in a favorable manner, efficiently and efficiently at the time of rolling of an axial product having a head.
It is an object of the present invention to provide an apparatus capable of continuously processing the head following the formation of the reduced diameter portion.

[0010]

Means for Solving the Problems In order to solve the above problems, the present invention is characterized in that it is configured as follows.

First, the invention according to claim 1 of the present application (hereinafter referred to as the invention)
According to the first invention), a shaft-shaped material provided with a head in advance is sandwiched between a pair of elongated flat dies each having a processing surface facing each other, and these dies are relatively moved in the longitudinal direction. By rolling the material between the two dies to form a reduced diameter portion at the lower part of the neck of the material, a rolling device is provided on the work surface of the pair of flat dies on the side of the material head side. A projection is formed from the end on the forming start side to the end on the rolling end side so as to protrude to form the reduced diameter portion at the lower part of the neck of the material, and is opposed to the lower surface of the head of the material in these flat dies. A predetermined range from the end on the rolling start side of the surface to be rolled up from a position lower than the portion on the rolling end side of the surface to form a tapered surface that pushes up the head of the rolling material. .

Further, the invention according to claim 2 of the present application (hereinafter referred to as “the invention”)
The second invention) is a method according to the first invention, in which the head of the material is machined on the rolling end side of a pair of flat dies provided with a ridge forming a reduced diameter portion at the lower part of the neck of the material. It is characterized in that a head processing portion to be applied is continuously provided.

With such a configuration, the following effects can be obtained according to the inventions of the present application.

First, in any of the first and second inventions, a predetermined range from the end on the rolling start side of the surface of the pair of flat dies facing the lower surface of the head of the material is set on the rolling end side of the surface. Since it is a tapered surface that rises from a lower position than the part, the material supplied and sandwiched between the ends on the rolling start side of the pair of flat dies is more than the case where the tapered surface is not provided Also, the head is set at a lower position. Then, from this state, when the material rolls between the pair of flat dies and moves toward the end on the rolling end side of both dies, the tapered surface causes the lower surface of the head to move upward, that is, the neck. Will move while being pushed up in the direction of extension.

Therefore, even if a volume dislocation toward the head of the material occurs due to the formation of a diameter-reduced portion at the lower part of the material neck by the ridges of the pair of flat dies, the volume dislocation moves upward of the head. The head is not lifted off the side surface of the flat die. As a result, the lower part of the neck is formed into a predetermined shape in which the reduced diameter portion smoothly continues to the lower surface of the head.

Since the lifting of the head is prevented as described above, the positional relationship between the reduced diameter portion and the head becomes constant when the formation of the reduced diameter portion is completed. As in the second invention, a head processing portion for performing a predetermined processing on the head of the material is continuously provided on a rolling end side of a pair of flat dies provided with a ridge portion forming a reduced diameter portion. Thus, following the formation of the reduced diameter portion, the head can be formed into a final shape or burnished.

[0017]

Embodiments of the present invention will be described below. In addition, the rolling device according to this embodiment is:
A rod member for a ball joint is manufactured. As shown in FIG. 13, a material A having a head portion A2 formed at one end of a shaft portion A1 as shown in FIG. B2 just below, that is, the reduced diameter part B in the lower part of the neck
The product B provided with No. 3 is manufactured.

As shown in FIG. 1, the rolling device 1 has a pair of elongated flat dies 2, 2 whose surfaces facing each other are processing surfaces, which are mounted on support members 3, 3, respectively. ing. One of the dies is a fixed die 2 ', which is fixed at a predetermined position. The other die is a moving die 2 ", and one end 2a of one end of the rolling start side is fixed to the fixed die 2'. End 2 on the same side as the start of rolling
From the rolling start position a close to a, through the state of overlapping with the fixed die 2 ', the other end 2b on the rolling end side of the other end approaches the end 2b of the fixed die 2' on the same rolling end side. It is possible to move in the longitudinal direction over the rolling end position a,
Driving means (not shown) for moving this is provided.

The fixed die 2 'and the movable die 2 "have exactly the same structure. As shown in FIG. 2, a fixed diameter forming portion X is formed in a fixed range from the end 2a on the rolling start side. ,
Further, a range from a portion overlapping a predetermined dimension to the end portion to the end portion 2b on the rolling end side is a head processed portion Y.

The reduced diameter portion forming portion X is provided along the side of the work surface of the die 2 on the side of the material head A2, and the material A that rolls between the pair of dies 2 is provided. A ridge 4 forming the reduced diameter portion B3 is provided at the lower part of the neck. The ridge portion 4 has a predetermined range X1 on the starting end portion X 'side.
3, the cross section is triangular as shown in FIGS. 3, 4 and 5, and in the predetermined range X2 of the intermediate portion, as shown in FIGS. 3 and 6, the cross section of the triangular cross section is A flat portion is provided on the top to form a trapezoidal cross section. Further, in a predetermined range X3 on the side of the end portion X ″, the trapezoidal cross section has a final shape corresponding to the shape of the neck-down diameter reduced portion B3 in the final product B. It is provided so as to continuously protrude from the starting end portion X ′ side and change to the final shape through each of the above shapes.

The above-mentioned predetermined range X1 on the side of the starting end X 'of the reduced diameter portion forming portion X is a tapered portion, and as shown in an enlarged view in FIG. The upper surface 5 facing the lower surface is a tapered surface 5a that rises gently from a position lower by a predetermined dimension z than the ranges X2 and X3 on the side of the middle portion and the end portion X ″.

On the other hand, the head processing portion Y has a configuration in which a concave groove 6 is provided along the longitudinal direction so as to be located above the upper surface 5 of the reduced diameter portion forming portion X. This groove 6
As shown in FIG. 7, the cross-sectional shape of the product B is a circular arc along the shape of the material head A2. Is provided so as to gradually change to a final shape corresponding to

Next, the operation of the rolling device 1 when manufacturing the product B shown in FIG. 14 will be described.

First, as shown by a solid line in FIG. 1, a movable die 2 "is fixed to an end 2a on the rolling start side by a fixed die 2 '.
Is set at the rolling start position a corresponding to the end 2a on the same rolling start side, and in this state, the material is formed between the ends 2a, 2a on the rolling start side of the working surfaces of the dies 2, 2. Supply A. At this time, as shown in FIG.
2 are supplied such that the lower surface thereof faces the upper surfaces 5 and 5 of both dies 2.

Then, from this state, when the movable die 2 "is moved in the direction of arrow C shown in FIG.
Rolling between the two, at this time, both dies 2,
The projecting ridges 4 and 4 provided on the processing surface of No. 2 bite into the lower part of the neck of the raw material A, and as shown in FIG. Then, as the cross-sectional shapes of the ridges 4, 4 gradually change as shown in FIGS. 4 to 6, the material A is formed into the reduced-diameter portion forming portions X, X of the two dies 2.
At the time of rolling to the end portions X ″, X ″ of the peripheral groove A3
Has a trapezoidal final shape, and the forming of the reduced diameter portion B3 in the product B is completed.

Further, since the two dies 2 and 2 are provided with a head processing portion Y continuously to the reduced diameter portion forming portion X,
Along with the movement of the movable die 2 ″, the material A enters the head processing portions Y, Y of the dies 2, 2, and the head A2 is held in the concave grooves 6, 6 in the processing portions Y, Y. Will be.
Then, as shown in FIG. 7, the material A is further rolled, so that the head A2 is finished in the final shape. Thereafter, as shown by a chain line in FIG.
When the end portion 2b on the side of the end of rolling has moved to the vicinity of the end 2b of the fixed die 2 'on the side of the end of rolling as well, the product B is discharged from between the dies 2 and 2.

As described above, according to the rolling device 1, as shown in FIG. 14, an axial product B having a reduced diameter portion B3 at the lower part of the neck can be obtained. To
By using the flat dies 2 and 2 as described above, the lower surface of the head B2 can be formed well.

That is, the upper surfaces 5 and 5 of the dies 2 and 2 whose lower surfaces of the head A2 of the material A are opposed to each other are connected to the end 2 on the rolling start side.
Since the tapered surfaces 5a, 5a rise gently in a predetermined range X1 from a, as shown in FIG. 8, while the material A rolls in the predetermined range X1 from the start of rolling,
The lower surface of the head A2 rolls while being pushed upward. Therefore, the ridges 4 on the dies 2 and 2
Even if the material dislocations 4 cause the material volume dislocations a and b to move up and down from the bite portion, the volume dislocations a
As a result, the head A2 does not rise from the upper surfaces 5, 5 of the dies 2, 2. Therefore, a problem that a stepped portion B4 as shown in FIG. 17 is formed in the lower portion of the neck of the product B due to the gap generated by the lifting is prevented, and the product B in which the lower portion of the neck is well molded can be obtained. Will be.

In addition, since the head A2 is prevented from being lifted during the formation of the reduced diameter portion, when the reduced diameter portion A3 is formed, the head A2 is not connected to the reduced diameter portion A3. The positional relationship will be constant. Therefore, material A
Moves smoothly from the reduced diameter part forming part X of the dies 2 and 2 to the head processing part Y, and the finishing of the head A2 in the processing part Y is continuous following the forming of the reduced diameter part A3. It will be performed in a typical manner.

The head processing portion Y may be formed by subjecting the head A2 of the material A to a final shape, or may be subjected to burnishing for finishing the surface of the corresponding portion A2.

The rolling device according to the above-described embodiment rolls a rod member having a spherical portion on the head for a ball joint.
For example, products D, E, F, and G shown in FIGS. 9 to 12 and other shaft-shaped parts having heads of various shapes are similarly applied.

[0032]

As described above, according to the rolling device according to the present invention, when a reduced diameter portion is formed at the lower part of the neck of a shaft-shaped product having a head, an unnecessary stepped portion is formed on the lower surface of the head. The reduced diameter portion is favorably formed without the occurrence of cracks. Further, according to the second aspect of the invention, it is possible to continuously perform a molding process, a burnishing process, and the like on the head, following the molding of the reduced diameter portion.

According to the present invention, in particular, the productivity is higher than in the case where the reduced diameter portion is formed by cutting, and since no chips are generated, high productivity can be obtained. As a device for manufacturing a shaft-shaped product with a head having a reduced diameter portion at the lower part of the neck, a device for efficiently manufacturing a good product is realized.

[Brief description of the drawings]

FIG. 1 is a schematic plan view of a rolling device according to an embodiment of the present invention.

FIG. 2 is a front view of a flat die in the rolling device.

FIG. 3 is an enlarged front view of a main part of the flat die of FIG. 2;

FIG. 4 is a sectional view taken along the line AA in FIG. 3;

FIG. 5 is a cross-sectional view taken along the line O-O of FIG. 3;

FIG. 6 is a cross-sectional view taken along a car line in FIG. 2;

FIG. 7 is a sectional view taken along a key line in FIG. 3;

FIG. 8 is an explanatory diagram of volume displacement of a material at the time of forming a reduced diameter portion.

FIG. 9 is a front view showing another example of a product formed by the rolling device of the present invention.

FIG. 10 is a front view showing another example of the product.

FIG. 11 is a front view showing another example of the same product.

FIG. 12 is a front view showing another example of the product.

FIG. 13 is a front view showing a material of a product that is a target of the rolling device according to the embodiment of the present invention.

FIG. 14 is a front view of the same product.

FIG. 15 is a front view showing a general configuration of a flat die for rolling.

FIG. 16 is an explanatory diagram of volume dislocation of a material shown as a conventional problem.

FIG. 17 is a front view of a product showing a conventional problem.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rolling device 2 Flat die 2a End on the rolling start side 2b End on the rolling end side 4 Ridge 5 Surface facing the lower surface of the head of the material (upper surface) 5a Tapered surface X Reduced diameter forming part Y Head processing part A Material B, D, E, F, G Product B1 Shaft part B2 Head B3 Reduced diameter part

Claims (2)

[Claims] An axial material having a head provided in advance is sandwiched between a pair of elongated flat dies each having a machined surface facing each other, and these dies are relatively moved in the longitudinal direction. A rolling device for a shaft-shaped product with a head that forms a reduced diameter portion at the lower part of the neck of the material by rolling the material between the two dies. On the side of the material, there are provided ridges which gradually project from the end on the rolling start side to the end on the rolling end side to form the reduced diameter portion below the neck of the material. A predetermined range from the end on the rolling start side of the surface opposite to the lower surface of the head of the material in the die rises from a lower position than the portion on the rolling end side of the surface, and the lower surface of the head of the rolling material is Rolling of shaft-shaped products with a head characterized by a tapered surface that pushes up apparatus. 2. A head processing part for processing the head of the material is continuously provided on a rolling end side of a pair of flat dies provided with a ridge forming a reduced diameter portion at a lower part of a neck of the material. The apparatus for rolling a shaft-shaped product with a head according to claim 1, wherein: