JPH0342232A - Apparatus for folding back end part of synthetic resin pipe - Google Patents

Abstract

PURPOSE:To closely bond the folded-back end part of a lining synthetic resin pipe to the outer peripheral surface of the end part of an outer pipe by expanding an annular split body to expand the end part of the lining synthetic resin pipe and folding back the lining synthetic resin pipe to the outer peripheral surface of the end part of the outer pipe and fitting the pipe and part in an annular groove. CONSTITUTION:The end part of the lining synthetic resin pipe 42 protruding from the end part of an outer pipe 41 is softened under heating and an annular split body 2 expanded in its diameter is inserted in the end part of said resin pipe 42. Next, a cylinder 3 is operated and the diameter of the annular split body 2 is expanded to expand the end part of the lining synthetic resin pipe 42. When a press plate 1 is moved to the right when the inner diameter of the annular split body 2 is expanded so as to become larger than the outer diameter of the outer pipe 41, the end part of the lining synthetic resin pipe 42 is folded back to the outer peripheral surface of the end part of the outer pipe 41. When the press plate 1 is further moved to the right, the end part of the outer pipe 41 covered with the lining synthetic resin pipe 42 is fitted in an annular groove 11 and the folded-back end part of the lining synthetic resin pipe 42 is closely bonded to the outer peripheral surface of the end part of the outer pipe 41.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention provides a method for manufacturing a lined pipe by covering the inner surface of an outer pipe such as a concrete pipe or a metal pipe with a lining synthetic resin pipe. The present invention relates to a synthetic resin pipe end folding device used when folding back the end of a lined synthetic resin pipe protruding from the end to cover the outer peripheral surface of the end of an outer pipe.

(Prior art and its section II) The present applicant previously proposed an end folding device for a synthetic resin pipe in Japanese Patent Application Laid-Open No. 104314/1983.

However, with this folding device, the inner mold is simply inserted into the lining synthetic resin tube that protrudes from the end of the outer tube, and the end is expanded at the collar. In some cases, the end portion of the outer tube did not expand sufficiently, and the outer circumferential surface of the end portion of the outer tube was not neatly covered with the end portion of the folded inner synthetic resin tube.

The present invention solves this problem and provides a device that can neatly fold back the end of a lined synthetic resin pipe to reliably cover the outer peripheral surface of the end of the outer pipe.

(Means for Solving the Problems) The present invention is a device for folding back the end of a lined synthetic resin pipe protruding from the end of an outer pipe onto the outer peripheral surface of the end of the outer pipe, the device having an annular groove. It consists of a pressing plate and an annular divided body divided into a plurality of pieces in the radial direction. Each annular segment is connected to a cylinder at the front of the press plate and expands in diameter radially.
It is characterized by being arranged so that its diameter can be reduced.

(Function) When the diameter of the annular segment inserted into the end of the inner synthetic resin pipe is expanded, the end of the inner synthetic resin pipe that protrudes from the end of the outer pipe expands, expanding the outer periphery of the outer pipe. folded to the side.

Therefore, when the end of the outer tube is inserted into the annular groove provided in the pressing plate, the end of the folded inner synthetic resin tube comes into close contact with the outer peripheral surface of the end of the outer tube.

(Example) Hereinafter, an example of the present invention will be described in detail based on the drawings. FIG. 1 is a partial vertical sectional view showing an embodiment of the folding device, and FIG. 2 is a front view of the folding device shown in FIG. 3 is a cylinder, and 4 is a lining pipe in which the inner surface of an outer pipe 41 such as a concrete pipe or a metal pipe is covered with an inner synthetic resin pipe 42 such as vinyl chloride resin.

An annular groove 11 having a predetermined depth is provided on the front surface of the pressing plate, and the diameters of the inner and outer walls of the annular groove 11 are such that the end of the outer tube 41 is covered with a lined synthetic resin tube 42. The diameter is set so that it can be inserted in the closed state. Also, press plate 1
An annular divided body 2 is provided on the front side of the annular groove 11 concentrically with the annular groove 11.

The annular division #2 is a ring body having an outer diameter approximately equal to the inner diameter of the lining synthetic resin pipe 42, which is divided into a plurality of parts in the radial direction. Although FIG. 2 shows an annular divided body 2 that is divided into four equal parts in the circumferential direction, each annular divided body may be divided into two to three equal parts, or six or more equal parts. 2
is supported by a support rod 21 and arranged to be able to expand and contract in diameter radially. That is, the support rod 21 is dovetail-fitted to the fixing plate 12 provided on the front surface of the pressing plate 1, and is slidably connected in the radial direction.

On the other hand, a support member 13 is vertically installed on the fixed plate 12.
A cylinder 3 operated by hydraulic pressure or compressed air is fixed to the support member 13, and a shaft 31 of the cylinder 3 is connected to a fixing member 22 vertically disposed on the support rod 21.

Therefore, when the cylinder 3 operates and the shaft 31 extends, as shown in the upper half of FIG. 1 (and FIG. 2),
The annular divided body 2 is in a reduced diameter state.

When the shaft rod 31 of the cylinder 3 is retracted from this state, the fixing plate 12 and the dovetail? The fitted support rods 21 move in the radial direction, and the annular divided body 2 expands in diameter.

Next, a process of folding back the end of the lining synthetic resin pipe 42 to the outer peripheral side of the end of the outer pipe 41 using this device will be explained. Outer tube 4
1 is covered with the lining synthetic resin pipe 42, first, the end of the lining synthetic resin pipe 42 protruding from the end of the outer pipe 41 is heated and softened.

Therefore, as shown in the upper half of FIG. 1, the annular segment 2 with a reduced diameter is inserted into the end of the lined synthetic resin pipe 42. Next, as shown in the lower half of FIG. Thus, the cylinders 3- are actuated to expand the diameter of each annular segment 2 at the same time, thereby expanding the end portion of the lining synthetic resin pipe 42. When the inner diameter of each annular divided body 2 expands to be larger than the outer diameter of the outer tube 41, the pressing plate 1
Move to the right side of Figure 1. Then, the end of the lining synthetic resin pipe 42 is folded back onto the outer peripheral surface of the end of the outer pipe 41.

Therefore, when the pressing plate 1 is further moved to the right side in Fig. 1,
The end of the outer tube 41 covered with the lining synthetic resin tube 42 is fitted into the annular groove 11, and the folded end of the lining synthetic resin tube 42 comes into close contact with the outer peripheral surface of the end of the outer tube 41. .

(Effects of the Invention) As described in detail above, the folding device of the present invention expands the end portion of the synthetic resin lining pipe by expanding the diameter of the annular division body, so the folding device of the present invention widens the end portion of the synthetic resin lining pipe. Since the end of the tube can be folded back on the outer circumferential surface of the tube, and the tube end is fitted into the annular groove, the folded end of the lined synthetic resin tube can be brought into close contact with the outer circumferential surface of the end of the outer tube. I can do it.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a partial vertical sectional view showing one embodiment of a folding device, and FIG. 2 is a front view of the folding device shown in FIG. 1. 1... Pressing plate 11... Annular groove 12
...Fixing member 13...Supporting member 2...
...Annular divided body 21...Support rod 3...
... Cylinder 31 ... Axis rod 41 ...
...Outer pipe 42...Inner joint resin pipe 4...
・・・・Lining pipe

Claims (1)

[Claims] A device for folding back the end of the lined synthetic resin pipe (42) protruding from the end of the outer pipe (41) onto the outer peripheral surface of the end of the outer pipe (41), and having an annular groove (11). Pressing plate (
1) and an annular divided body (2) divided into multiple pieces in the radial direction.
An end of a synthetic resin pipe, characterized in that each annular segment (2) is connected to a cylinder (3) on the front surface of the pressing plate (1) so as to be able to expand and contract in diameter radially. Part folding device.