JP2011056532A - Spinning - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a spinning for molding a product having no thin portion. <P>SOLUTION: The spinning tapering a rotating work W by abutting a roller R thereon to mould the work W into a predetermined shape includes: a first step for moving the roller R in the other end along an axis O direction with the roller R pressed to the work W in a center axis O side; a second step for stopping the roller R closing to a specific portion P of the work W, for separating the roller R from the work W, and for forming a protuberance 97 protruding to the outside of a diameter direction at the specific portion P of the work W; and a third step for moving the roller R along the axis O with the roller R pressed to the work W in the center axis O side and compressing the protuberance 97, which increases the thickness of the specific portion P of the work W. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a spinning method. More specifically, the present invention relates to a spinning method for shrinking a cylindrical member and forming it into a predetermined shape.

  Conventionally, a wheel rim of an automobile is formed by reducing the diameter of the substantially center of a cylindrical workpiece and making the outer peripheral surface into a concave cross-sectional shape. A so-called spinning method is known as one method for forming such a wheel rim from a cylindrical workpiece. In this spinning processing method, a diameter of the workpiece is reduced by pressing a roller against the workpiece inward from the outer peripheral surface while rotating the cylindrical workpiece (see Patent Document 1).

JP 2004-314117 A

Here, a change in the plate thickness of the workpiece when the diameter of the cylindrical workpiece is reduced will be described.
FIG. 8 is a cross-sectional view showing the configuration of the workpiece Wu before processing and the workpiece Wp after processing. More specifically, FIG. 8 is a diagram illustrating an example in which a product Wp having a concave cross-sectional shape is formed by performing a conventional spinning process on a cylindrical workpiece Wu. In the spinning process, the workpiece R is moved along the axial direction while pressing the roller R against the workpiece Wu along the radial direction with respect to the workpiece Wu rotating about the axis parallel to the axial direction. Mold Wp.

  When the spinning process as described above is performed on the workpiece, each element of the workpiece extends along the axial direction and contracts along the radial direction. Basically, when the workpiece extends along the axial direction, the plate thickness of the workpiece decreases. However, when the workpiece contracts in the radial direction, the peripheral length decreases, and thus the plate thickness of the workpiece increases.

As described above, when the diameter of the cylindrical workpiece is reduced, the workpiece is contracted in the radial direction so that the material is excessively increased as a result, and the material is insufficient as a result of the workpiece extending along the axial direction. The portion where the plate thickness decreases occurs depending on the shape of the cross section.
For example, when a recess having a narrow and deep cross-sectional shape as shown in FIG. 8 is formed in the workpiece, the plate thickness at the most reduced diameter portion indicated by a broken line in FIG. 8 tends to be thin. In addition, among these, the plate thickness tends to be particularly thin at a portion having a large curvature indicated by a one-dot chain line.

  As described above, when a thin-walled portion is generated in the product, the strength of the entire product is lowered. For this reason, in order to ensure sufficient strength for a product, it is necessary to use a thick workpiece in anticipation of a reduction in the plate thickness in the conventional spinning method, and thus it is difficult to reduce the weight of the product.

  This invention is made | formed in view of the above-mentioned subject, and it aims at providing the spinning processing method which can shape | mold the product without a thin part.

  The present invention is a spinning processing method in which a cylindrical member is contracted by applying a spatula (for example, a roller R, which will be described later) to a rotating cylindrical member (for example, a workpiece W, which will be described later) and formed into a predetermined shape. A first step of moving the spatula toward the other end side along the axial direction while pressing the spatula against the cylindrical member toward a central axis (for example, an axis O described later), and the spatula When reaching a specific location (for example, a specific location P described later) of the cylindrical member, the spatula is stopped from moving while the spatula is separated from the cylindrical member, and the specific location of the cylindrical member is radially outward. A second step of forming a raised portion (e.g., a raised portion 97 to be described later), and the spatula is moved along the axial direction while pressing the spatula against the cylindrical member toward the central axis, By compressing the ridge Characterized in that it comprises a third step of the thickness of the specific part of the cylindrical member.

According to the present invention, the spatula is moved toward the other end side along the axial direction while pressing the spatula toward the central axis side of the cylindrical member, and when the spatula approaches the specific portion of the cylindrical member, the spatula is moved. Stop and move away from the cylindrical member. Thereby, the raised part which protrudes to a radial direction outer side can be formed in the specific location of a cylindrical member. And it moves along an axial direction, pressing a spatula to a cylindrical member to the center axis | shaft side, and compresses a protruding part. In this way, after forming the raised portion so that the circumference of the specific location becomes longer and expanding the diameter of the specific location, the circumference is reduced again by reducing the diameter of the specific location by compressing the circumference further. The specific portion can be thickened according to the length once extended.
Here, when a thin part occurs in the product, i.e., when a portion where the plate thickness is thinned when spinning processing is performed on the cylindrical member, the specific part is defined as a part of the cylindrical member that is a thin part. Is made thick by the above procedure. As a result of molding, the cylindrical member is subjected to such a thickening process at the initial stage of molding before the cylindrical member is molded into a product shape in anticipation of the plate thickness becoming thin. The plate thickness can be made uniform. Moreover, since a thin part does not generate | occur | produce in a product, a cylindrical member with a thin plate | board thickness can be used compared with the former, ensuring required intensity | strength.

  In this case, when the spatula is moved along the axial direction in the first, second, and third steps, it is preferable to compress the cylindrical member along the axial direction.

  According to the present invention, in the first and second steps, the spatula is moved along the axial direction while compressing the cylindrical member, so that a raised portion is formed at the moving destination of the spatula, that is, at a specific portion of the cylindrical member. Can be made easier. Further, in the third step, the material constituting the raised portion can be constrained in a specific location by compressing the cylindrical member along the axial direction, so that the raised portion is compressed toward the central axis and contracted. In this case, the specific portion can be more reliably thickened.

It is a mimetic diagram showing composition of a spinning processing system to which a spinning processing method of the present invention is applied. It is sectional drawing along the axis line O of the wheel rim manufactured by the spinning processing system which concerns on the said embodiment. It is sectional drawing which shows the workpiece | work and division | segmentation type | mold state in each process of the spinning processing method which concerns on the said embodiment. It is sectional drawing which shows the workpiece | work and division | segmentation type | mold state in each process of the spinning processing method which concerns on the said embodiment. It is sectional drawing which shows the workpiece | work and division | segmentation type | mold state in each process of the spinning processing method which concerns on the said embodiment. It is sectional drawing which shows the workpiece | work and division | segmentation type | mold state in each process of the spinning processing method which concerns on the said embodiment. FIG. 5 is a cross-sectional view taken along line VII-VII in FIG. 4. It is sectional drawing which shows the structure of the workpiece | work before a process and the workpiece | work after a process.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic diagram showing a configuration of a spinning processing system 1 to which a spinning processing method of the present invention is applied.

  The spinning processing system 1 includes a first split mold 21 and a second split mold 22 that hold a cylindrical workpiece W, a rotation device 3 that rotationally drives the workpiece W, a compression device 4 that compresses the workpiece W, and a roller R. And a control panel (not shown) that controls the entire system.

  As will be described in detail below, the spinning processing system 1 is configured to apply a roller R from an outer peripheral surface to a work W rotating around an axis O as a central axis, thereby reducing the work W and dividing the dies 21 and 22. This is formed into a shape along the outer peripheral surface of the. The cylindrical body manufactured by shrinking tube processing with this spinning processing system 1 is used for a wheel rim of an automobile, for example.

  The first split mold 21 and the second split mold 22 are provided on the left side in FIG. 1 and the right side in FIG. 1 along the same axis O, respectively. The outer peripheral surface of the first split mold 21 is formed in a shape that is shaped like the left side of the wheel rim, and the outer peripheral surface of the second split mold 22 is formed in a shape that is shaped like the right side of the wheel rim. Therefore, by matching these divided dies 21 and 22, a single mold having the shape of the wheel rim is formed.

  The first split mold 21 is connected to the rotating device 3 via a support column 23, and the second split mold 22 is connected to the compression device 4 via a support column 24. On the left end side of the first split mold 21 and the right end side of the second split mold 22, a left end flange portion 25 and a right end flange portion 26 with which the left end and the right end of the work W abut are respectively formed. Is fixed to the both flange portions 25 and 26. The first split mold 21 and the second split rotation 22 may each be provided with a clamp that fixes both ends of the workpiece W.

FIG. 2 is a sectional view taken along the axis O of the wheel rim 9 manufactured by the spinning processing system 1.
As shown in FIG. 2, the wheel rim 9 is formed by molding a workpiece along the outer peripheral surfaces of the split dies 21 and 22 in a state of abutting each other. A concave reduced diameter portion 91 is formed substantially at the center of the wheel rim 9. More specifically, the reduced diameter portion 91 has a first taper portion 92 and a taper larger than the first taper portion 92 in order from the left side to the right side in FIG. A second taper portion 93 that decreases in diameter, a linear portion 96 that extends parallel to the axial direction, a third taper portion 94, and a fourth taper portion 95 that expands in diameter with a smaller taper angle than the third taper portion 94, Consists of. Among these taper parts 92-95, the taper angle of the 2nd taper part 93 is the largest. Therefore, the sharpest acute angle of the wheel rim 9 is formed between the second taper portion 93 and the linear portion 96.

Returning to FIG. 1, the rotating device 3 rotationally drives the first split mold 21 together with the workpiece W and the second split mold 22 with the axis O as the central axis.
The roller moving device 6 rotatably holds a disk-shaped roller R with an axis substantially parallel to the axis O as a central axis, and moves the roller R in a three-dimensional space.
The compression device 4 presses the second split mold 22 toward the first split mold 21 with a predetermined thrust along the direction of the axis O. Thereby, in a state where the workpiece W is set in the split molds 21 and 22, a compressive force along the axis O direction acts on the workpiece W.

Next, a specific procedure of the spinning method by the spinning system 1 as described above will be described.
3 to 6 are cross-sectional views showing the state of the workpiece W and the split molds 21 and 22 in each step, respectively.

First, as shown in FIG. 3, the workpiece W is set in the split molds 21 and 22. More specifically, the left end side of the workpiece W is abutted against the flange portion 25 of the first split mold 21 and fixed, and the right end side of the workpiece W is abutted against the flange portion 26 of the second split mold 22 and clamped. Fix it.
Next, the second split mold 22 is driven to the first split mold 21 side along the axis O with a predetermined thrust, whereby a predetermined magnitude of compressive force is applied to the work W from both ends. Then, by rotating the first split mold 21 around the axis O as the central axis, the workpiece W is rotated while applying a compressive force.

Thereafter, the second split mold 22 is moved to the first split mold 21 while the roller R is pressed against the outer peripheral face of the rotating workpiece W from the outer peripheral face toward the central axis O in the procedure shown in FIGS. To approach. Thereby, as shown in FIG. 2 described above, the workpiece W is reduced in diameter and formed into a product shape corresponding to the shape of the outer peripheral surfaces of the split dies 21 and 22.
By the way, as described above, when the diameter of the cylindrical workpiece W is reduced, the workpiece W is contracted in the radial direction, so that the portion of the material increases as a result, and the workpiece extends along the central axis O direction. Therefore, a portion where the material is insufficient and the plate thickness decreases as a result is generated depending on the shape of the product. In particular, in the example of the present embodiment, a thin portion tends to occur between the second tapered portion 93 and the straight portion 96 in the product (see FIG. 2 described above).

  Therefore, in the spinning method according to the present embodiment, a portion where a thin portion is generated in a product is anticipated, and a thickness of a specific portion that becomes a thin portion as a result of molding is increased among workpieces before molding is completed. Processing is performed at the initial stage of molding. Below, the specific procedure of this thickening process is demonstrated.

The thickening process is mainly divided into three steps: a first step, a second step, and a third step.
First, in the first step, as shown in FIG. 4, while pressing the roller R from the outer peripheral surface to the center axis O side of the workpiece W, the roller R is moved from the second split mold 22 side along the axis O direction. It moves toward the one-part mold 21 side.
Next, in the second step, when the roller R reaches the specific location of the workpiece W, the movement of the roller R is stopped and the roller R is separated from the workpiece W. Thereby, the raised part 97 which protrudes to the radial direction outer side in the specific location P among the workpiece | work W in the early stage of shaping | molding is formed.

Here, the reason why the raised portion 97 is formed at the specific portion P by performing the above-described processing in the initial stage of molding will be described.
7 is a cross-sectional view taken along line VII-VII in FIG.

  As shown in FIG. 7, when the roller R is pressed against the rotating workpiece W, the roller R rotates along the outer peripheral surface of the workpiece W, and the workpiece W is sequentially contracted. At the stage where the deformation of the workpiece W in the radial direction is shallow, the increase in the material due to the reduced diameter of the workpiece W is larger than the decrease in the material due to the workpiece W extending along the axial direction. Moreover, since the workpiece | work W is compressed along the axial direction by the 1st division type and the 2nd division type as mentioned above, the extension along an axial direction is restrict | limited. For this reason, the plate thickness of the portion W2 contracted by the roller R is larger than the plate thickness of the portion W1 not contracted by the roller R.

  However, if the tube is contracted deeper than a predetermined depth, it becomes impossible to follow the volume change caused by the contraction tube only by such an increase in the plate thickness, so that a peripheral length difference occurs in the workpiece W. At this time, since the workpiece W is compressed along the axial direction and the post-processing hardening of the roller R in the moving direction is not generated, a raised portion 97 is formed at a specific portion P as shown in FIG. The

  Next, in the third step, as shown in FIG. 5, the roller R is pressed against the workpiece W toward the central axis O, and the roller R is pushed along the axis O direction rather than the raised portion 97. As shown in FIG. 6, the protruding portion 97 is compressed toward the central axis O by the roller R. As described above, the workpiece W is applied with a compressive force along the axis O direction, and the extension of the material along the axis O direction is limited. Therefore, when the raised portion 97 is compressed, the circumferential length is shortened. The specific part P becomes thick by the amount.

  As described above, in the thickening process of the present embodiment, the raised portion 97 is formed so that the peripheral length of the specific portion P is long, and the specific portion P is enlarged in diameter, and then the peripheral length is shortened again. The specific portion P can be made thick according to the length of the circumference by reducing the diameter of the specific portion P.

  After the thickening process as described above is performed and the specific portion P of the workpiece W is thickened, the roller R is pressed against the center axis O side of the workpiece W according to a predetermined procedure. It is formed into a shape along the outer peripheral surface. Here, the specific portion P that has been thickened becomes thinner in the process of forming into the shape of the split molds 21 and 22, but by making it thicker than the other parts, the plate thickness of the wheel rim is uniform as a result. Can be.

According to this embodiment, there are the following effects.
(1) When the roller R is moved toward the first split mold 21 along the axis O direction while pressing the roller R against the center axis O side of the workpiece W, the roller R reaches the specific portion P of the workpiece W. The movement of R is stopped and separated from the workpiece W. Thereby, the raised portion 97 that protrudes radially outward can be formed at the specific location P. Then, while pressing the roller R against the workpiece W toward the central axis O side, the roller R moves from the first split mold 21 side to the second split mold 92 side along the axis O direction to compress the raised portion 97. . Thus, after forming the protruding part 97 so that the circumference of the specific location P becomes long and expanding the diameter of this specific location P, it compresses again so that this circumference becomes short, and this specific location P is reduced in diameter. Thereby, the specific location P can be made thick according to the part for which the circumference was once extended.
Here, as a result of forming, the workpiece W is subjected to such thickening processing at the initial stage before forming the workpiece W into a product shape in anticipation of the plate thickness becoming thin. The plate thickness can be made uniform. Moreover, since a thin part does not generate | occur | produce in a product, the workpiece | work with a thin plate | board thickness can be used compared with the past, ensuring required intensity | strength.

  (2) In the first and second steps, by moving the roller R along the direction of the axis O while compressing the workpiece W, a raised portion 97 is formed at the movement destination of the roller, that is, a specific portion P of the workpiece W. Can be made easier. In the third step, the material constituting the raised portion 97 can be constrained in the specific portion P by compressing the workpiece W along the direction of the axis O, so that the raised portion 97 is compressed toward the central axis O side. When the tube is contracted, the specific portion P can be more reliably thickened.

  Note that the present invention is not limited to the above-described embodiment, and modifications, improvements, and the like within the scope in which the object of the present invention can be achieved are included in the present invention.

DESCRIPTION OF SYMBOLS 1 ... Spinning processing system 21 ... 1st division type 22 ... 2nd division type 9 ... Wheel rim 97 ... Raised part R ... Roller (spar)
P: Specific location

Claims (2)

A spinning method for shrinking a cylindrical member by applying a spatula to a rotating cylindrical member and forming the cylindrical member into a predetermined shape,
A first step of moving the spatula toward the other end side along the axial direction while pressing the spatula against the cylindrical member toward the center axis;
When the spatula reaches a specific part of the cylindrical member, the movement of the spatula is stopped, the spatula is separated from the cylindrical member, and the protrusion protrudes radially outward at the specific part of the cylindrical member. A second step of forming a part;
While pressing the spatula against the cylindrical member toward the central axis, the spatula is moved along the axial direction, and the raised portion is compressed to make a specific portion of the cylindrical member thick. A spinning process method comprising the steps of:   In the first and second steps, when the spatula is moved along the axial direction, the cylindrical member is compressed along the axial direction.

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