JPH0751755A - Device for forming bead on pipe material - Google Patents

Abstract

PURPOSE:To form bead on the outer peripheral surface of a pipe material in one action. CONSTITUTION:The bead forming device is constituted with a holding mold 4 for holding a pipe material 1 to immobile state, a wedge member 7 inserted into the inner periphery of the pipe material 1 held in the holding mold 4 as close as possible, balls 12 deciding the inner periphery of the bead and a driving means 17 for pressing the wedge member 7. The wedge member 7 has a first and a second wedge members 8, 9, divided into two at the central part in the axial direction and the first wedge member 8 provides a first inclining surface 13 for giving so sufficient stroke as to lift by almost half length of the diameter of the ball 12 from the position of the lower hole 1a of the pipe material 1 to the ball 12. The second wedge member 9 provides a second inclining surface 14 projecting to outside of the pipe member 1 by giving the remaining stroke to the ball 12 and a ball holding hole 15 for holding the ball 12 at the lower end position of this inclining surface 14. The pressing part 16 for pressing the second wedge member 9 by abutting on the rear part of the second wedge member when the first inclining surface 13 reaches the position connected with the second inclining surface 14 is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bead forming apparatus for forming a bead on the outer peripheral surface of a pipe material.

[0002]

2. Description of the Related Art A bead 2 may be formed on the side surface of a pipe material 1 for connecting another pipe material to the outer peripheral surface of the pipe material or for other purposes, as shown in FIG.

In the conventional molding of the bead 2, the pipe material 1 is held in a mold, and a piece 3 as shown in FIG. 8 is passed through a prepared hole formed in the peripheral surface of the pipe material 1. The bead 2 is formed by expanding the prepared hole.

[0004] In this molding, the piece 3 is held immovable immediately below the prepared hole of the pipe material 1, a rod is inserted from the outside of the pipe material 1 through the prepared hole, and this rod is attached to the piece 3 of the pipe material 1. After being connected to the screw hole 3a by screwing or the like, the bead 2 is formed by pulling this rod and passing the piece 3 through the prepared hole.

[0005]

However, in the above-mentioned prior art, means for holding the piece 3 in the pipe material 1 in an immovable state, means for screwing the rod into the piece 3, means for pulling out the rod, etc. are individually required. However, since the apparatus is diverse, not only the apparatus itself becomes complicated, but also the number of steps is increased and the processing cycle is long, which causes various problems in terms of workability and work efficiency.

In view of this, the present invention uses a ball for forming a bead, and makes it possible to perform positioning and holding of the ball and bead forming operation only by behavior in one direction,
Accordingly, it is an object of the present invention to provide a bead molding device for a pipe material, which is capable of simplifying the device and also shortening the processing cycle.

[0007]

As a means for solving the problems of the above-mentioned prior art, the present invention provides a holding die for holding a pipe material in an immovable state, and a holding die from one side of the holding die. A wedge member that is inserted into the inner periphery of the pipe material held therein as closely as possible, a ball that determines the inner periphery of the bead to be molded, and a drive means that presses the wedge member, The wedge member is 2 at the center in the axial direction.
A first slope having divided first and second wedge members, the first wedge member providing the ball with a stroke sufficient to raise approximately half the diameter of the ball from a position between the ball and the prepared hole of the pipe material. The second wedge member is provided with a second inclined surface for giving a residual stroke to the ball to project to the outside of the pipe material, and a ball holding hole for holding the ball at a lower end position of the inclined surface. The rear portion of the wedge member is provided with a pressing portion that abuts against the rear portion of the second wedge member and presses the rear portion when the first inclined surface reaches a position where the first inclined surface is continuous with the second inclined surface.

[0008]

The ball is held in the ball holding hole of the second wedge member, and the first wedge member is pushed in to push the ball up in the ball holding hole by the first inclined surface of the first wedge member, so that the prepared hole of the pipe material is opened. Spread out. When the ball is pushed up by about half its own diameter, the ball reaches the level of the second inclined surface of the second wedge member, and at this time, the pressing portion of the first wedge member abuts against the rear portion of the second wedge member. Since this is pushed in, the ball is delivered to the second inclined surface of the second wedge member, and thereafter, the ball is pushed up by the second inclined surface of the second wedge member and passes through the prepared hole, at which time the bead molding is completed. At the same time, the balls are discharged to the outside of the pipe material. Therefore, one action of pressing the wedge member completes all the steps from holding the ball at a predetermined position, forming the bead, and discharging the ball.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the embodiments shown in the drawings. FIG. 1 shows a cross section of an embodiment of a bead molding apparatus according to the present invention. A holding die 4 for holding a pipe material 1 in an immovable state is composed of an upper die 4A and a lower die 4B, and a pipe is provided on a mating surface thereof. The material 1 has a mold surface to which half of the fitting is fitted, and stoppers 5 and 5 for determining the position of the tip of the pipe material 1 in the insertion direction are provided on the mold surface. Further, a bead forming hole 6 having an inner diameter corresponding to the outer diameter of the bead 2 to be formed is formed in the upper mold 4A.

The wedge member 7 has a circular cross section having an outer diameter which is inserted into the inner periphery of the pipe material 1 held in the holding die 4 from one side of the holding die 4 as closely as possible. The wedge member 7 is composed of a first wedge member 8 and a second wedge member 9 which are bisected at the center in the axial direction, and the mating surfaces of these wedge members 8 and 9 are shown in cross section in FIG. Ridge 1
There are 0 and a groove 11, and they are slidably fitted together.

The first wedge member 8 has a ball 12 for forming a bead 2 through the prepared hole 1a of the pipe material 1.
A (steel ball) is formed with a first inclined surface 13 that gives a stroke sufficient to raise the diameter of the ball 12 by approximately 1/2 from the lower position of the prepared hole 1a of the pipe material 1.

The second wedge member 9 has a second inclined surface 14 for giving the remaining stroke to the ball 12 so as to project the ball 12 to the outside of the pipe material 1, and the ball 12 at the lower end position of the inclined surface 14. Ball holding hole 15 for holding
Are formed. This second wedge member 9 is a pipe material 1
Has substantially the same length as and is shorter than the first wedge member 8.

At the rear portion of the first wedge member 8, when the first inclined surface 13 reaches a position which is continuous with the second inclined surface 14, it abuts on the rear end 9a of the second wedge member 9. A pressing portion 16 that presses is formed.

A hydraulic cylinder or the like is used as the pressing means 17 for pressing the first wedge member 8 in the arrow X direction. The upper die 4A is clamped to the lower die 4B by a hydraulic cylinder 18.

Next, the operation of the above embodiment will be described. The pipe material 1 (FIG. 4) in which the bead forming pilot hole 1a is previously drilled is set in the holding mold 4 such that the pilot hole 1a is aligned with the bead molding hole 6 of the upper mold 4A. Ball holding hole 1 of the second wedge member 9 of the wedge member 7 to be inserted inside
The ball 12 is loaded in the inside of the 5.

When the first wedge member 8 is inserted in the direction of the arrow X by the driving means 17 after being set in this way, the ball 12 is gradually pushed up by the advance of the first inclined surface 13, and the ball 1 in the prepared hole 1a of the pipe material 1 is pushed. Push it apart (state in Figure 5).

When the ball 12 is pushed up by about ½ of its own diameter, the first wedge member 8 is located at the position indicated by the symbol Y in FIG. 1, and the first inclined surface 13 of the first wedge member 8 is located.
And the second inclined surface 14 of the second wedge member 9 are in a continuous state.

At this time, the pressing portion 16 of the first wedge member 8 comes into contact with the rear end 9a of the second wedge member 9 and starts pushing the second wedge member 9. As a result, the ball 12 is pushed up by the second inclined surface 13 of the second wedge member 9, and when the region of the second inclined surface 13 has finished moving forward, the second wedge member 9 is moved to the position indicated by the symbol Z in FIG. When the ball 12 is positioned, the bead 2 is formed between the ball 12 and the inner peripheral surface of the hole 6 of the upper die 4A by raising the peripheral edge of the prepared hole 1a (state of FIG. 6), and the ball 12 is bead-formed as it is. It is discharged from the use hole 6 to the outside.

Thereafter, when the hydraulic cylinder 18 of the upper die 4A of the holding die 4 is operated to separate the upper die 4A from the lower die 4B, the beaded pipe material 1 is exposed and pulled to the right in FIG. It can be removed by pulling it out.

The holding die 4 is clamped by the hydraulic cylinder 18
Of course, mechanical means other than the above may be used, and it is needless to say that the right and left split type may be used instead of the vertical split type.

[0021]

As described above, according to the present invention, since the bead can be formed by only one action of inserting the wedge member when forming the bead on the peripheral surface of the pipe material, a single drive source is used. Well, the device configuration can be greatly simplified. Also, since the beads for bead molding only have to be inserted into the ball holding holes of the second wedge member, it is not necessary to provide any special holding means, which significantly shortens the processing cycle and improves workability and work efficiency. Can be significantly increased.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a bead molding apparatus according to the present invention.

2 is a cross-sectional view of the wedge member in FIG.

3 is a plan view of a second wedge member in FIG.

FIG. 4 is a cross-sectional view showing a pipe material before bead processing.

FIG. 5 is a sectional view of a pipe showing a state during bead molding.

FIG. 6 is a cross-sectional view of the pipe material showing a state after bead molding is completed.

FIG. 7 is a perspective view of a pipe material on which beads are formed.

FIG. 8 is a perspective view showing a conventional bead molding piece.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pipe material 1a Prepared hole 2 Bead 4 Holding type 6 Bead forming hole 7 Wedge member 8 First wedge member 9 Second wedge member 12 Ball 13 First inclined surface 14 Second inclined surface 15 Ball holding hole 16 Pressing portion 17 Drive means

Claims (1)

[Claims] 1. A holding die for holding a pipe material in an immovable state,
A wedge member that is inserted into the inner circumference of the pipe material held in the holding mold from one side of the holding mold as closely as possible, a ball that determines the inner circumference of the bead to be molded, and the wedge. Drive means for pressing the member, wherein the wedge member has a first and a second wedge member that are bisected at a central portion in the axial direction, and the first wedge member is attached to the ball under the pipe material. A second inclined surface having a first inclined surface that gives a stroke sufficient to raise approximately half the diameter of the ball from the position between the second wedge member and the second wedge member that gives the remaining stroke to the ball and projects to the outside of the pipe material. A surface and a ball holding hole for holding a ball at a lower end position of the inclined surface, and the second wedge member is provided at a rear portion of the first wedge member when the first inclined surface reaches a position where the first inclined surface is continuous with the second inclined surface. Abut the rear part and press it Bead molding devices of the pipe, characterized by comprising a pressing portion.