JP2007044704A - Apparatus for forming pipe material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a forming apparatus which can uniformly fasten a plurality of split dies by a single driving source. <P>SOLUTION: First, a pipe material is fitted on a mandrel 30 to carry out the drawing and caulking of the pipe material. At this time, the upper and lower split dies 11, 12 composing an outer die 1 are in an opened state. From this state, the upper split die 11 composing the outer die 1 is moved downward. As a result, four split dies 21, 22, 23, 24 composing an inner die 2 equally move toward their center, and an exhaust pipe can be drawn and caulked at the same time by means of forming surfaces 26, 27 formed on the inside surfaces of the four split dies. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a molding apparatus capable of simultaneously performing drawing and / or caulking on a pipe material, particularly a double pipe such as an exhaust pipe.

  There are apparatuses disclosed in Patent Document 1 and Patent Document 2 as apparatuses for forming a pipe material between molds. In Patent Document 1, as a molding device for caulking a ground terminal as a tubular member, a structure in which a punch for embossing is attached to six divided molds in which hexagonal molded parts are formed when the mold is clamped Is disclosed.

  Patent Document 2 discloses a structure in which an inner mold is disposed in an outer mold and a molding portion is provided in the inner mold as a bulge molding apparatus.

JP 2002-233918 A JP 2003-251418 A

  In the molding apparatus disclosed in Patent Document 1, each divided mold is advanced and retracted by a hydraulic cylinder. For this reason, the number of hydraulic cylinders increases, the apparatus becomes large, and the force acting on each divided mold is not necessarily equal. Furthermore, drawing and caulking cannot be performed simultaneously.

  On the other hand, since the forming apparatus disclosed in Patent Document 2 is for bulge processing, a pressure fluid is supplied to the inside of the pipe material, and the pipe material is formed while spreading outward, and the forming pressure is equally applied to the pipe material. However, it is not suitable for drawing or caulking. Moreover, when a pipe material is a double pipe, the shape which can be shape | molded with many restrictions will be restricted.

  In order to solve the above problems, a molding apparatus according to the present invention includes an outer mold and an inner mold disposed in the outer mold, and the outer mold is composed of upper and lower divided molds. One of the divided molds can be moved forward and backward relative to the other, and the upper and lower divided molds are formed with a slide surface that defines the arrangement space of the inner mold. It is divided into four split molds, the outer surfaces of these four split molds are slide surfaces that are in sliding contact with the upper and lower split mold slide surfaces, and the inner surfaces of the four split molds are molding surfaces. It was set as the structure by which the elastic member urged | biased in an opening direction was provided between the side surfaces of a split type | mold.

  In the above, even if the upper and lower split molds are tilted 90 ° and placed on the left and right, the function as the molding apparatus does not change. Therefore, the upper and lower split molds defined in this application include those split on the left and right.

  Further, it is most effective that the slide surface is inclined by 45 ° with respect to the upper and lower divided type forward and backward moving directions. Furthermore, when the forming surface is formed with a drawing forming surface and a caulking forming surface, and the caulking forming surface is formed across adjacent divided molds, an equal load is applied to each divided mold. To do.

  Furthermore, an example of a method for forming a tube material using the above-described forming apparatus is to insert a double pipe into a cored bar arranged at the center of the four divided molds constituting the inner mold, and then to mount the outer mold. Molding formed on the inner surface of the four split molds by moving one of the upper and lower split molds in the closing direction and moving the four split molds constituting the inner mold evenly toward the center by this movement. The double pipe is subjected to drawing and caulking at the same time.

According to the molding apparatus according to the present invention, the molding pressure acting on the pipe material is equalized for each split mold of the inner mold, so that it is possible to perform precise drawing and caulking.
Further, according to the present invention, drawing and caulking can be performed simultaneously, and the number of conventional processes can be reduced.
Furthermore, the pressing force at the time of shaping | molding is performed uniformly by providing the shaping | molding surface to which it crimps over the adjacent division | segmentation type | mold.

  Preferred embodiments of the present invention will be described below with reference to the drawings. Here, FIG. 1 is a front view of the mold opening state of the molding apparatus according to the present invention, FIG. 2 is a perspective view of one split mold among the four split molds constituting the inner mold of the molding apparatus, FIG. 3 is a front view of the molding apparatus in the mold opening state, and FIG. 4 is a view showing an end portion of the exhaust pipe after molding.

  The molding apparatus includes an outer mold 1 and an inner mold 2. The outer mold 1 includes upper and lower split molds 11 and 12, and the upper split mold 11 engages with a slide member 13 and moves forward and backward with respect to the lower split mold 12 by driving a hydraulic cylinder and a motor (not shown). .

  Smooth slide surfaces 11a and 11b having an inverted V shape are formed on the lower surface of the split mold 11 above the outer mold 1, and a smooth slide having an inverted V shape is formed on the lower surface of the split mold 12 below. Surfaces 12a and 12b are formed, and the inner mold 2 is arranged in a space surrounded by the slide surfaces 11a, 11b, 12a and 12b.

  Further, clearance recesses 11c and 12c are formed between the slide surfaces 11a and 11b and between the slide surfaces 12a and 12b, into which corners of the split mold of the inner mold 2 described later enter when the mold is closed. Yes.

  The inner mold 2 is divided into four divided molds 21, 22, 23 and 24, and the outer surfaces of these four divided molds are slid onto the slide surfaces 11a, 11b, 12a and 12b of the upper and lower divided molds 11 and 12, respectively. The sliding surfaces 21a, 22a, 23a, and 24a are in contact with each other, and the four divided mold inner surfaces 21b, 22b, 23b, and 24b are formed as molding surfaces, and further between the four divided mold side surfaces 21c, 22c, 23c, and 24c. Are provided with springs 25 as resilient members for urging the four split molds in the opening direction.

  As shown in FIG. 2, a drawing surface 26 for drawing and a forming surface 27 for caulking are formed on the inner surfaces 21b, 22b, 23b, 24b of the four split molds. In particular, when the mold forming surface 27 for caulking is clamped, the two divided molds are formed so that the caulking process forming surface 27 of the adjacent divided mold continuously forms one molding surface for caulking. It is formed across.

  Further, a cored bar 30 for extrapolating a tube material to be formed is disposed at the center of the four divided dies 21, 22, 23, 24.

  In the above, for example, in order to perform drawing processing and caulking processing on one end of an exhaust pipe having a double-pipe structure, first, the exhaust pipe is extrapolated to the core metal 30. At this time, the upper and lower divided molds 11 and 12 constituting the outer mold 1 are in an open state, and the four divided molds 21, 22, 23 and 24 constituting the inner mold 2 are caused by the elastic force of the springs 25. Pushed in the opening direction, the four split mold slide surfaces 21a, 22a, 23a, and 24a are in sliding contact with the slide surfaces 11a, 11b, 12a, and 12b of the upper and lower split molds 11 and 12 without a gap.

  From this state, the upper split mold 11 constituting the outer mold 1 is moved downward. Then, the split molds 21 and 22 of the inner mold 2 are pushed downward by the slide surfaces 11a and 11b of the split mold 11 of the outer mold 1, and as a result, the split molds 21 and 22 are relatively moved to the slide surfaces 11a and 11b. And the movement is combined with the downward movement, and moves toward the center of the core 30 as indicated by the arrow in the figure.

  Further, the split dies 22 and 23 constituting the inner mold 2 also move toward the center of the core metal 30 by the same principle. As a result of the above movement, the four divided molds 21, 22, 23, 24 constituting the inner mold 2 move evenly toward the center, and the exhaust surfaces are formed by molding surfaces 26, 27 formed on the inner surface of the four divided molds. Pipes are drawn and caulked at the same time. The end of the exhaust pipe after molding is shown in FIG.

  In the embodiment, both the drawing surface 26 for drawing and the molding surface 27 for caulking are formed on the inner surface of the four divided dies constituting the inner mold 2, but only one of them is formed. May be.

Front view of the mold opening state of the molding apparatus according to the present invention Perspective view of one split mold among four split molds constituting the inner mold of the molding apparatus Front view of the mold opening state of the molding apparatus of the molding apparatus Figure showing the end of the exhaust pipe after molding

Explanation of symbols

1 ... Outer mold,
DESCRIPTION OF SYMBOLS 11, 12 ... Upper and lower split type 11a, 11b, 12a, 12b ... Slide surface 11c, 12c ... Escape recessed part 13 ... Slide member 2 ... Inner die 21, 22, 23, 24 ... Split type 21a, 22a of inner die , 23a, 24a ... Slide surfaces 21b, 22b, 23b, 24b ... Inner side surface of inner mold 21c, 22c, 23c, 24c ... Side surface of inner mold 25 ... Spring 26 ... Molding surface for drawing 27 ... For caulking process Molding surface 30 ... Core

Claims (4)

In a molding apparatus that performs drawing or caulking on a pipe material, the molding apparatus includes an outer mold and an inner mold disposed in the outer mold, and the outer mold is divided into upper and lower divided molds. One of these upper and lower divided molds can be moved forward and backward relative to the other, and the upper and lower divided molds are formed with slide surfaces that define the arrangement space of the inner mold. The inner mold is divided into four divided molds, the outer surfaces of the four divided molds are slide surfaces that are in sliding contact with the upper and lower divided mold slide surfaces, and the inner surfaces of the four divided molds are molding surfaces. In addition, a tubular member forming apparatus is characterized in that a resilient member for biasing the four divided molds in the opening direction is provided between the side surfaces of the four divided molds. 2. The tube forming apparatus according to claim 1, wherein the slide surface is inclined by 45 ° with respect to the advancing and retracting directions of the upper and lower divided dies. 3. 3. The tube forming apparatus according to claim 1, wherein a drawing forming surface and a caulking forming surface are formed on the forming surface, and the caulking forming surface is formed across adjacent divided dies. An apparatus for forming a pipe material characterized by being made. A pipe material molding method using the molding apparatus according to claim 1 to 4, wherein a double pipe is inserted into a core metal arranged at the center of four split molds constituting the inner mold, Next, one of the upper and lower divided molds constituting the outer mold is moved in the closing direction, and by this movement, the four divided molds constituting the inner mold are moved evenly toward the center, and the four divided molds are A method for forming a pipe material, wherein the double pipe is subjected to drawing and caulking simultaneously with a molding surface formed on an inner surface.