JP4393470B2 - Drawing method and apparatus - Google Patents

Description

  The present invention relates to a drawing method and apparatus for drawing a hollow cylindrical material, and more particularly to a drawing method and apparatus for forming an inner peripheral portion of a hollow cylindrical material.

  Conventionally, for example, a hollow cylindrical material (hereinafter referred to as “work”) is subjected to a drawing process, and the inner peripheral portion thereof is shaped according to the step of the mandrel (internal gear shape or stepped inner peripheral surface shape). When it is necessary to form, the work method is to fix the work to the rotating spindle, press the mandrel placed at the tip of the pressing table that faces the spindle and press it into the inner periphery of the work, and place it on the tool table. A method of spinning the outer peripheral surface of the workpiece with a drawn roller for drawing is employed (see, for example, Patent Document 1).

FIG. 5 shows a drawing apparatus used for this processing method. The drawing device 20 is provided with a chuck 4 disposed on the rotary main shaft 2 and a mandrel 3 disposed opposite to the rotary main shaft 2 and press-fitted into an inner peripheral portion of a work W attached to the chuck 4. It comprises a pressing table 8 and a tool table 5 provided with a drawing roller R3 for drawing the outer peripheral surface of the workpiece W attached to the chuck 4. The mandrel 3 is rotatably attached to the pressing table 8 via a bearing or the like so as to rotate together with the rotation main shaft 2.
The pressing table 8 is placed on a traveling rail 9a laid on the moving table 9 so as to move in parallel with the axial direction of the rotary spindle 2, and is arranged to be movable by appropriate means such as a pulse motor.
The tool base 5 is placed on a traveling rail 6a laid on the traveling base 6 so as to move at right angles to the axial direction of the rotary spindle 2, and can be moved by appropriate means such as a pulse motor in the same manner as the moving base 9. Arrange. Further, the traveling table 6 is also placed on a moving rail 7 a laid on the moving table 7 so as to be movable in the axial direction of the rotating spindle 2, and a pulse motor or the like like the pressing table 8 and the tool table 5. It is arranged to be movable by appropriate means.

By the way, as the shape of the mandrel 3, a desired shape for rolling the inner peripheral surface shape of the final product can be selected. For example, as shown in FIGS. The size of the cylindrical portion 3a, the stepped portion 3b having an outer diameter larger than the inner diameter of the material W, and the flange portion 3c for restricting the flow of the workpiece W by drawing are configured. In such a case, the drawing process is performed in the following steps.
The workpiece W, which is a workpiece, is gripped and fixed to the chuck 4 (see FIG. 6A). Then, the pressing base 8 is shifted to the main shaft 2 side, and the cylindrical portion 3a that is the tip portion of the mandrel 3 is inserted into the inner peripheral portion of the workpiece W (see FIG. 6B). Thereafter, the pressing base 8 is further moved to the main shaft 2 side, and the step portion 3 b of the mandrel 3 is pushed into the inner peripheral portion of the workpiece W. Thereby, the edge part of the workpiece | work W is expanded (refer FIG.6 (c)). At this time, a gap s is formed between the end face of the workpiece W and the flange portion 3c of the mandrel 3 according to the amount of meat flow generated when the inner diameter of the workpiece W is increased by drawing. .
While the mandrel 3 is pressed and inserted into the inner peripheral portion of the workpiece W or while being pressed and inserted, the rotary main shaft 2 is rotated by a driving device M such as an electric motor, and the squeezing roller R3 is moved as shown in FIG. It is made to contact | abut to the circumference part of W, and it draws toward the press stand 8 from the main axis | shaft 2 which is the direction of the arrow X along the original outer diameter (outer peripheral part) of the workpiece | work W.
When the squeezing is completed to the vicinity of the flange portion 3c of the mandrel 3 (see the two-dot chain line in FIG. 7A), the squeezing roller R3 is separated from the work W.

However, in the drawing method using this drawing device, the step of the mandrel 3 as shown in FIG. A gap is generated between the portion 3b and the inner peripheral portion of the workpiece W, and the outer periphery of the end portion is also slightly expanded and does not have a desired shape. Therefore, as shown in FIG. There has been a problem that the drawing process needs to be performed twice or more.
Japanese Patent Laid-Open No. 9-239472

  In view of the problems of the above-described conventional drawing method, the present invention provides a drawing method capable of forming a desired shape by a single drawing process in the drawing process for forming the inner peripheral portion of a hollow cylindrical material. And an apparatus for the same.

In order to achieve the above-described object, the drawing method of the present invention is such that a hollow cylindrical workpiece is attached to the tip of a rotating spindle, and a mandrel having a diameter larger than the inner diameter of the workpiece is provided from one end of the workpiece to the inner periphery. after expanding the end portion of the workpiece by pressing insert, a drawing method of applying a contact with drawing the squeegee roller to the outer peripheral surface of the workpiece, is expanded by pressing insertion of the mandrel The drawing work is performed by moving in the main shaft direction a drawing roller provided with a plurality of contact portions that contact the work peripheral surface on the peripheral surface of the drawing roller along the original outer diameter of the work. It is characterized by.

Further, the drawing apparatus of the present invention for carrying out the drawing method includes a chuck for gripping and fixing a cylindrical workpiece at the tip of the spindle, and pressing from one end side of the workpiece to the inner peripheral portion at a position facing the spindle. Comprising a pressing table provided with a mandrel having a diameter larger than the inner diameter of the workpiece for expanding the end of the workpiece by insertion, and a tool table provided with a drawing roller for drawing the workpiece. A drawing device in which a tool table is arranged so as to be movable in parallel and perpendicular to the spindle, and the drawing roller arranged on the tool table is in contact with a work peripheral surface and presses and inserts the mandrel. A feature is that a plurality of contact portions to which drawing is performed by moving the drawing roller in the main axis direction along the original outer diameter of the workpiece are provided at the end portion of the expanded workpiece.

According to the drawing method and apparatus of the present invention, the outer diameter of the workpiece is increased to the end of the workpiece that is expanded by pressing and inserting the mandrel onto the circumferential surface of the drawing roller. The workpiece is drawn by a drawing roller provided with a plurality of contact portions for drawing by moving the drawing roller along the main axis along the workpiece. On the other hand, it is possible to provide a drawing method and apparatus capable of performing a plurality of times of pressing with one drawing and forming into a desired shape with one drawing.

  Hereinafter, embodiments of the plastic working method of the present invention will be described with reference to the drawings. In addition, about the structure similar to a conventional apparatus, the same code | symbol and a series of code | symbol are attached | subjected, and description is abbreviate | omitted.

  1 to 3 show a first embodiment of the drawing method and apparatus of the present invention.

The drawing apparatus 1 of the present invention includes a main shaft 2 rotatably disposed on a frame 11 by a driving device M such as a motor, a chuck 4 for attaching a cylindrical workpiece W to the tip of the main shaft 2, and the main shaft. a pressing board 8 which is disposed the mandrel 3 on the tip is press-fitted to the inner peripheral portion of the workpiece W mounted on the chuck 4 with 2 facing the position, the tool base were provided with squeeze rollers R1 for performing drawing to the workpiece W 5 It consists of.

As in the conventional example, the tool table 5 is movable in a direction parallel to and perpendicular to the main shaft 2 by the traveling table 6 and the moving table 7. The traveling direction of the traveling platform 6 and the movable platform 7 is an example in which the traveling platform is moved in a direction orthogonal to the main shaft 2 and the moving platform 7 is moved in a direction parallel to the main shaft 2 as in the conventional example. May be configured in parallel with the main shaft 2 and the movable table 7 may be configured in a direction orthogonal to the main shaft 2.
Further, in this embodiment, an example is shown in which one tool base 5 is disposed and one squeezing roller R1 is processed, but the tool base 5 is disposed so as to be paired with the axis of the main shaft 2 as a boundary. However, the processing may be performed by the two squeezing rollers R1 arranged to face each other with the workpiece W interposed therebetween.

  The drawing roller R1 provided on the tool table 5 of the drawing apparatus 1 according to the present invention is provided with a plurality of contact portions that contact the work peripheral surface. In Example 1, as shown in FIG. Shows an example in which two contact portions a1 and a2 are provided.

  The abutting portions a1 and a2 are formed on the peripheral surface of the squeeze roller R1, and it is preferable to form a valley b between them and form a certain distance as shown in the figure.

  A forming method for forming the inner peripheral portion of the hollow cylindrical workpiece W using the drawing device 1 having the above-described configuration will be described.

  First, as in the conventional example, the tool table 5 is positioned at a position where it does not interfere with the chuck 4 disposed at the tip of the spindle 2 and the mandrel 3 disposed at the tip of the pressing table 8, and the workpiece W is conveyed manually or automatically. It is attached to the chuck 4 by an apparatus and fixed with a gripping pressure (see FIG. 6A).

  Thereafter, the pressing base 8 is moved to the main shaft 2 side, and the stepped portion 3b of the mandrel 3 is pushed into the inner peripheral portion of the workpiece W (see FIG. 3A). At this time, similarly to the conventional example, a gap between the end face of the workpiece W and the flange portion 3c of the mandrel 3 according to the amount of meat flow generated when the inner diameter of the workpiece W is increased by drawing. s is provided.

  Then, in a state where the mandrel 3 is pressed and inserted into the inner peripheral portion of the work W, or while being pressed and inserted, the rotation main shaft 2 is rotated by a driving device M such as an electric motor, and as shown in FIG. Is drawn from the main shaft 2 in the direction of the arrow X toward the pressing table 8 along the original outer diameter (outer peripheral portion) of the workpiece W. At this time, the drawing process is started from the point where the expansion line L is expanded by press-fitting the mandrel 3, and the contact part a1 of the drawing roller R1 presses the peripheral surface of the work W toward the mandrel 3 side. Although the drawing process is performed, the peripheral surface of the workpiece W that has been subjected to the drawing process is expanded by the spring back when the contact portion a1 of the drawing roller R1 passes. However, in the squeezing roller R1 of the present invention, the drawing process is performed while further pressing the peripheral surface of the workpiece W where the next abutting part a2 is to be expanded beyond the abutting part a1 and further beyond the valley part b. Therefore, the amount of return due to the spring back can be minimized and formed into a desired shape by a single drawing process.

  FIG. 4 shows a second embodiment of the drawing roller used in the drawing method and apparatus of the present invention.

  As shown in FIG. 4, the drawing roller R2 used in the drawing apparatus 1 of the present embodiment is provided with three contact portions that contact the peripheral surface of the workpiece W and two valley portions b therebetween. The drawing process can be performed while pressing the peripheral surface of the work W three times by one roller movement by the contact portions a1 to a3. Therefore, even in the case of a material having a springback characteristic larger than that in the first embodiment, or when the outer diameter difference between the cylindrical portion 3a and the step portion 3b of the mandrel 3 is large and the end portion of the workpiece W is greatly expanded. The amount of return due to the springback can be effectively minimized, and a desired shape can be formed by a single drawing process.

  The drawing method and apparatus of the present invention have been described based on the embodiments. However, the present invention is not limited to the configurations described in the above embodiments, and the configurations are appropriately set within the scope of the invention. Can be changed.

  As described above, the drawing method and apparatus of the present invention are provided with a plurality of contact portions that contact the work peripheral surface on the peripheral surface of the squeezing roller, minimizing the return amount due to the spring back, and performing a single drawing process. Since it has the property that it can be molded into a desired shape, it is suitable not only for applying to a new drawing device, but also by modifying the existing drawing device to change the drawing roller. Can be used.

It is a schematic plan view of the drawing apparatus of this invention. It is a front view of the drawing roller used for the drawing apparatus of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing which shows the processing method using the drawing apparatus of this invention, (a) is the state before drawing, (b) is the state which has started to perform drawing on a workpiece | work circumference part with a drawing roller. , (C) shows a state in which the drawing process has been completed on the workpiece circumferential portion by the drawing roller. It is a front view of another Example of the drawing roller used for the drawing apparatus of this invention. It is a schematic plan view of the conventional drawing apparatus. It is explanatory drawing which shows the processing method using the conventional drawing apparatus, (a) is the state before drawing, (b) is the state which inserted the cylindrical part of the mandrel into the workpiece | work, (c), The state where the step part of the mandrel is press-fitted into the workpiece is shown. FIGS. 7A and 7B are explanatory views showing a processing method using the conventional drawing apparatus following FIG. 6, in which FIG. 6A shows a state in which a work roller is drawn by a drawing roller, and FIG. FIG. 4C shows a state where the processed workpiece end portion has returned to the expanded state, and FIG. 5C shows a state where the workpiece circumferential portion has been drawn again by the drawing roller.

DESCRIPTION OF SYMBOLS 1 Drawing apparatus 2 Spindle 3 Mandrel 3a Cylindrical part 4 Chuck 5 Tool stand 8 Press stand R1 Drawing roller R2 Drawing roller a1 Contact part a2 Contact part a3 Contact part W Workpiece

Claims (2)

After a hollow cylindrical workpiece is attached to the rotating spindle tip, and a mandrel having a diameter larger than the inner diameter of the workpiece is inserted into the inner periphery from one end of the workpiece, and then the end of the workpiece is expanded. A drawing method in which a drawing roller is brought into contact with the outer peripheral surface of the workpiece to perform drawing , and the end of the workpiece expanded by pressing and inserting the mandrel is aligned with the original outer diameter of the workpiece. A drawing method characterized in that the drawing process is performed by moving a drawing roller having a plurality of contact portions in contact with the work peripheral surface on the peripheral surface of the drawing roller in the main axis direction . From a chuck that grips and fixes a cylindrical workpiece at the tip of the spindle, and an inner diameter dimension of the workpiece for expanding the end of the workpiece by pressing and inserting it from one end of the workpiece to the inner periphery at a position facing the spindle A drawing device comprising a pressing table provided with a mandrel having a large diameter and a tool table provided with a drawing roller for drawing a workpiece, wherein the tool table is arranged to be movable parallel to and perpendicular to the main shaft. The squeezing roller disposed on the tool table is in contact with the work peripheral surface and is expanded by pressing and inserting the mandrel along the original outer diameter of the work. A drawing apparatus comprising a plurality of contact portions for drawing by moving a drawing roller in a main axis direction .

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