JPS59133021A - Method and apparatus for manufacturing bulged pipe - Google Patents

Abstract

PURPOSE:To form a bulged pipe with a fixed thickness and free in the number of bulge the interval thereof and the size by bulging a part of a pipe with deformation of an elastic body in a gentle U-shape so as to be moded in a bending die. CONSTITUTION:A pipe P is clamped on both sides thereof with a fixed die 11 and a mobile die 15. As the tip of a core metal 1 is pressed to pressurize an elastic body 2, the pipe is bulged in a U-shape with the deformation of the elastic body. Upon the release of the pressurization, the elastic body is returned to the original state. With the mobile die 15 contacting a stopper 24, the fixed die 11 is advanced. Said bulged section P1 is turned to a U-shaped P2 corresponding to a space formed with a protruded wall 16 of the mobile die 15 and a recess 12 of the fixed die 11. The clamped state of the bending die is released. After the bending die is backed to the original state, with the reclamping thereof, the U-shaped P2 advances by one pitch. The bulging work can be done continuously for the pipe by repeating the operation sequentially.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for manufacturing a corded pipe.

Conventionally, known methods for stringing out pipes include hydraulic nozzle processing and bulge processing using an elastic body such as urethane rubber. However, the conventional processing direction is to insert a pipe, which will serve as a molding base material, into a mold that has been previously formed into a predetermined shape (e.g., bellows shape, gourd shape, etc.), pressurize the inside of the pipe, and then mold it into the predetermined shape. It was something to do. Therefore, the processed product is necessarily thinner than the base material, and there is a drawback that uniform strength cannot be obtained at each part. To avoid this, it is necessary to have a device that pushes the base material according to its deformation, or it is extremely difficult to design and manufacture it.Furthermore, since the shape of the mold is fixed, for example, the number of strings to be drawn, the distance between them, etc. However, when changing the size, etc., a corresponding mold must be manufactured each time.

The present invention has been made in order to improve the above-mentioned drawbacks, and provides a method and apparatus for manufacturing a corded pipe that has a substantially constant wall thickness and can arbitrarily change the number, spacing, size, etc. of the corded pipes. The purpose is to

Below, the present invention will be explained with reference to the drawings.
In the figure, ■ is a core metal whose center part is connected with an elastic body 2 such as urethane rubber, and the base end of the core metal 1 (left side in the figure) can be freely attached to and detached from a core support device 4 fixed to a base plate 3. A collar 5 is movably attached to the proximal end side of the core bar 1 for initial positioning of a pipe to be fitted onto the core bar 1.

This core bar 1 is raised and lowered by a core bar support device 4.

Reference numeral 6 denotes a cylinder for primary bending of the pipe provided on the tip side of the core metal 1, and its piston rod 7 is opposed to the tip of the core metal 1.

8 and 8' are bending molds of the same shape, each of which is perpendicular to the core metal 1 by a clamp cylinder 9, and the elastic body 2 of
It is provided so that it can be freely moved towards and away from the ground. This bending mold 8 (8”
), as shown in FIG.
A movable mold 15 that can be moved toward and away from the fixed mold is provided.

That is, the fixed mold 11 is fixed to the end face of the mold mount 10, and has a recess 12 formed inside its tip, and a spring chamber 13 with an enlarged diameter in the center and a pin insertion hole 14 with a small diameter communicating with the spring chamber 13.
has. On the other hand, the movable mold 15 has a projecting wall 16 facing the recess 12 at its tip, and a slide pin 17 protruding from the inner surface of the central part has a coil spring 18 wound around it between it and the spring chamber 13. Holt axis 19 coupled to 17
Insert the two adjustment screws 20 through the pin insertion hole 14.
Supported by Therefore, the movable mold 15 is urged by the coil spring 18 and separates from the fixed mold 11 in this state, and the distance between the molds is adjusted by the adjustment screw 20, that is, the projecting wall 16
The distance d between the recess 12 and the recess 12 can be adjusted.

Reference numeral 21 denotes a mounting plate for the bending dies 8, 8', which is moved forward and backward in the axial direction of the core metal 1 on the base end side of the core metal 1 by a secondary bending cylinder 22. Reference numeral 23 denotes a pedestal that supports the tip side of the core metal 1, and this pedestal 23 is provided with a stopper 24 for the movable mold 15.

Next, a fourth example of the manufacturing method of the present invention using the above-mentioned apparatus will be described.
This will be explained with reference to figures (a) to (g).

First, by operating the core metal support device 4, the core metal 1 is bent into a mold 8,
8', and after extrapolating the pipe P from its tip side, lower it to the position of the bending molds 8 and 8'.

Next, as shown in (A), the clamp cylinders 9.9 are operated, and both sides of the pipe P are clamped from both sides by the bending mold part, the fixed mold 11, and the movable mold 15. At this time, the molds 11 and 15 are pressed against the inside of the elastic body 2.

Next, when the next bending cylinder 6 is operated and the piston rod 7 presses the tip of the core metal 1, the elastic body 2 is pressurized (b), as shown in (b) (the recess 12 of the fixed mold 11 and the movable mold 1
The bulge 2a is formed between the protruding wall 16 of 5 and the projecting wall 16 of 5. As a result, the pipe P is drawn in along with the deformation of the elastic body 2, and bulges P1 in a mountain shape following the bulge 2a.

Next, if the pressure applied by the -th bending cylinder 6 is released, (
As shown in c), the elastic body 2 returns to its original shape.

Next, the mold mount 10 is moved by the operation of the secondary bending cylinder 22.
When the movable mold 15 is moved, the movable mold 15 comes into contact with the strike collar 24 as shown in (d), but in this case, the distance between the movable mold 15 and the fixed mold 11 is maintained by the intervention of the coil spring 18.
When further moved, the fixed mold 1 resists the elastic force of the spring 18.
1 moves forward, and as shown in (e), the bulge 21 portion deforms into a sharper chevron shape P2. That is, if the chevron type P2 is the movable type 1
However, in this case, since it is a kind of crushing, the thickness of the chevron-shaped portion 22 remains unchanged. It has almost the same thickness as the original pipe P.

Next, the bending molds 8, 8 are bent by the operation of the clamp cylinder 9.
' is released from the clamped state, and the secondary bending cylinder 22 is operated to make a mold (10
to retreat.

Next, when the bending molds 8 and 8' are completely returned to their original states and clamped again, the chevron-shaped portion P2 advances by a certain angle, as shown in FIG. They are in contact with each other.

Hereinafter, by sequentially repeating the steps (a) to (g), it is possible to continuously string out the chevron-shaped P2 portion, that is, the pipe.

As explained above, in the present invention, a core metal with an elastic body such as urethane rubber interposed between two core metal rods is inserted into a vibrator, and one core metal rod number of the two core metal rods and the other core metal rod are inserted into a vibrator. By pressing it to the side and deforming the elastic body to shorten the overall length of the core metal, a part of the pipe is pulled in and bulged into a gentle mountain shape, and then the pipe is placed in a bending mold that accommodates the bulge. The structure is such that the bulging part is crushed in the axial direction of the core metal (pressure is applied and formed into almost the same shape as the four parts of the bending mold), so the wall thickness is almost the same as that of the pipe used as the material. It is possible to continuously manufacture corded pipes.Also, the height and spacing of the corded parts can be changed by simply changing the spacing between the fixed and movable molds and the space formed in both molds. I can do it.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which Fig. 1 is a plan view of a pipe string pulling device, Fig. 2 is a side view thereof, Fig. 3 is an enlarged explanatory view of the bending mold 8, and Fig. 4 (A). ~(1.) is an explanatory diagram of the operating state. DESCRIPTION OF SYMBOLS 1... Core metal, 2... Elastic body, 8, 8'... Bending type, 11... Fixed type, 12... Recessed part, 15... Movable type. Patent applicant Seiwa Fuko Co., Ltd. 103

Claims (2)

[Claims] (1), urethane rubber, etc. (l) is placed between the two core rods.
4' Insert the core metal with the body interposed into the pipe, press one core metal rod of the core metal rod toward the other core metal rod side, deform the elastic body, and shorten the total length of the core metal. A step of drawing in a part of the pipe and bulging it into a gentle mountain shape, and applying pressure to crush the bulge in the axial direction of the core metal in a bending die that accommodates the bulge. A method for manufacturing a corded pipe, which comprises a step of forming the four parts into a shape that is almost the same as the four parts of a bending mold. (2) A core support device for fixing one end of a core metal with an elastic body such as urethane rubber interposed between two core metal rods, and a core support device for fixing the other end of the core metal on a Heas board. Equipped at a predetermined interval from each other with primary bending cylinders that press to deform the elastic body and shorten the core metal to bulge the pipe sheathed on the core metal into a gentle mountain shape; A bending mold, in which a fixed mold and a movable mold form a concave portion that can approach and separate from the bulging portion of the pipe and accommodates the bulged portion, is placed between the core metal support device and the primary bending cylinder. movable in one direction along the axis of the movable mold, and a slot for regulating the movement of the movable mold.
- A manufacturing device for a corded pipe, which is equipped with a collar and a secondary bending cylinder that presses the bending die to form the bulge into approximately the same shape as the recess.