JPH0232977B2 - - Google Patents

Abstract

PURPOSE:To close securly an end of a pipe, by pressing a hot plate to the end of a synthetic resin pipe having longitudinally extending through-holes in the circumferential wall, and rotating the plate about the axis of the pipe to seal the through-holes with the melted resin. CONSTITUTION:The through-holes 2 formed in the synthetic resin pipe P and open to opposite ends of the pipe circumferential wall 1 extend longitudinally between an inner surface of pipe circumferential wall 1a and an outer surface 1b. The hot plate is pressed to the end of the pipe P, and is rotated gradually about the axis of the pipe in one direction to heat and melt the pipe end part so that the melted resin 21 is sealed into the through-holes 2 and at the same time the excess of the resin 21 projects from both the inner and outer peripheries of the pipe end part to form melted flashes 2c, 2d, and thereafter the hot plate is removed to form a slightly protruded part 2b. Then, a disk 5 having pairs of bits 6, 7 located at four equi-spaced positions along concentric circles having radii corresponding to the inner and outer radii of the pipe P is pressed to the pipe end part, and is rotated to cut off the flashes 2c, 2d by the cutting tools 6, 7.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for closing the end face of a synthetic resin pipe (hereinafter simply referred to as a perforated pipe) having a through hole in the pipe peripheral wall in the pipe axial direction. The purpose is to seal the molten resin in the opened through hole to ensure that the end surface of the tube is closed.

As shown in FIG. 6, in the perforated pipe described above, a through hole 2 that opens to both end faces of the pipe peripheral wall 1 is formed to penetrate in the pipe axial direction between the pipe peripheral wall inner surface 1a and the outer surface 1b. An insertion port 3 is formed at one end, and a socket 4 is formed at the other end, and the two pipes are connected by inserting the insertion port 3 of one pipe into the socket 4 of the other pipe.

Perforated pipes made of synthetic resin such as polyvinyl chloride resin are used as sewage pipes, etc., but if both ends of the hole are left open when buried underground, groundwater may seep in through the hole. It is important that both ends of the through hole are reliably closed, since there is a drawback that sewage water flowing into the main pipe or conversely flowing out into the ground. For this reason, the conventional method has been to close the end face of the tube, but this has not been satisfactory.

The present invention is designed to eliminate the above-mentioned drawbacks, and is made by pressing a hot plate against the end face of a perforated tube, and rotating the hot plate around the tube axis to allow the molten resin to flow through the through hole opened at the end face of the tube. The molten burrs protruding from the inner and outer peripheries of the tube end surfaces are then cut and removed.

This will be explained below with the help of drawings. FIG. 5 shows a state in which the open end of the through hole 2 is not completely closed by the conventional method and a small hole 2a remains. improved by

That is, pressing a hot plate against the tube end of the perforated tube P,
When the hot plate is gradually rotated in a fixed direction about the tube axis or alternately rotated in opposite directions at fixed time intervals to heat and melt the tube end, the molten resin is caused by the rotation of the hot plate. As a result, the excess molten resin is sealed in the through hole 2 in a dragged state, and on the other hand, the excess molten resin protrudes from the inner and outer peripheries of the tube end face, resulting in molten burrs.

In FIG. 1, the through hole 2 is completely sealed and closed by the molten resin 21, and molten burrs 2c are formed on the inner and outer peripheries of the tube end surface.
2d is a partially sectional front view showing a state where 2d has occurred. FIG.

Note that when the hot plate is removed, the molten resin 21 that closes the through hole 2 will swell slightly to form a protrusion 2b, so after flattening it by pressing a cold plate against it as shown in Figure 2, the inner and outer peripheries of the tube end should be Melted burrs 2c, 2
Cut and remove d using a byte.

As shown in FIG. 4, a pair of cutting tools 6 and 7 are provided on one surface of a disc 5 at 90° intervals along concentric circles corresponding to the inner and outer diameters of the perforated pipe P, and the disc 5 is rotated. Then, the molten burrs 2c and 2d on the inner and outer peripheries of the tube end are scraped off using bits 6 and 7 to finish the tube end free of molten burrs as shown in FIG.

The hot plate and room temperature plate may preferably be coated with Teflon (registered trademark) to prevent the molten resin from adhering and to facilitate its separation.

As described above, the present invention can easily and reliably close the through-hole end of a perforated pipe, and the perforated pipe whose through-hole end is closed does not allow groundwater or sewage to flow in or out through the through-hole 2. Not only is there no molten burr on the inner and outer peripheries of the tube ends, there are advantages such as easy and reliable connection by inserting the insertion port of the tube into the socket, which is of great practical benefit.

[Brief explanation of drawings]

Figures 1 to 3 are partially cutaway front views showing the steps of the closing method according to the present invention, Figure 4 is a perspective view of a cutting tool for cutting and removing molten burrs, and Figure 5 is a failure to close a through hole according to the conventional method. A partially cutaway front view showing the condition;
FIG. 6 is a cutaway perspective view of the perforated tubes connected to each other. 1 is a tube peripheral wall, 2 is a through hole, 2c and 2d are melted burrs, 6 and 7 are cutting tools for cutting burrs, and P is a perforated tube.

Claims (1)

[Claims] 1. Pressing a hot plate against the end face of a synthetic resin pipe that has a through hole in the pipe axial direction on the pipe peripheral wall, and enclosing the molten resin into the through hole opened in the pipe end face while rotating the hot plate around the pipe axis. 1. A method for closing an end face of a synthetic resin pipe having a through hole in the pipe axial direction in the pipe peripheral wall, the method comprising: cutting off and removing molten burrs protruding from the inner and outer peripheries of the pipe end face.