JPH0159901B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a foam tube with a surface treatment such as an embossed pattern used for a heat-retaining tube or the like.

When making thermal insulation tubes from thermoplastic resin foam, conventionally, a foam sheet with an embossed surface is slitted into a narrow strip, which is then molded into a cylindrical shape through a wrapper-shaped molding device. The joints are thermally bonded.

For this reason, the manufacturing of the foam sheet, surface treatment such as slitting and embossing, and tube-making process are all separate processes, resulting in poor production efficiency. I had a problem with it getting worse.

The present invention has been made in view of the above-mentioned problems, and involves cutting the abdomen open on an extruded thermoplastic resin foam tube line to form a sheet body, and then re-tubing the sheet body. By applying surface treatment such as embossing to the foam, it is possible to manufacture foam tubes with higher roundness and desired surface treatment with higher production efficiency than conventional foams. An object of the present invention is to provide a method for manufacturing a body tube.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

In FIG. 1, reference numeral 1 indicates a foam tube (round tube) of crosslinked polyolefin resin, which is continuously extruded and foamed from an extrusion molding machine 2, cooled by a cooling device (not shown), and then transported along a predetermined path. It is guided to the tube laparotomy cutter device 3 at the later stage. The tube laparotomy cutter device 3 has a guide rod 4 with a conical tip located on the above-mentioned path, and a cutter 5 that hangs down from the guide rod 4 with the cutting edge on the distal end side of the guide rod 3, and the guide rod 4 is formed by extrusion molding. It is fixed to a fixing member (not shown) via a mounting frame 6 toward the machine 2 side. The rear end portion of the guide rod 4 is smoothly widened and flattened toward the rear end to form a guide portion 4a having a flat upper surface. Since the guide rod 4 is on the path along which the foam tube 1 travels as described above, the foam tube 1 guided to the tube laparotomy cutter device 3 automatically fits into the guide rod 4 and passes through the guide rod 4. During this process, the abdomen is opened from below with the cutter 5, and the opened foam tube 1 is gradually expanded into a sheet shape by the shape guide portion 4a of the guide rod 4 and placed on the roll surface of the take-up roll 7. Since the rear end of the guide rod 4 reaches near the top of the roll surface of the take-up roll 7, the foam sheet 1A rests on the top of the roll surface. A film crimping roll 8 is arranged with its roll surface facing the topmost portion. Further, an embossing roll 9 is arranged with the roll surface facing approximately 90 degrees from the topmost part, and the embossing roll 9 is placed between the roll 9 and the crimping roll 8 on the roll surface of the take-up roll 7. A heater 10 is provided to radiate heat toward the vehicle.

The foam sheet 1A placed on the roll surface of the take-up roll 7 passes under the film pressing roll 8, and during this passage, the film 11 is pressed onto the outer surface. This film 11 is a reinforcing or decorative film. As shown in FIG. 4a, the foam sheet 1A to which the film has been crimped moves while remaining on the roll surface of the take-up roll 7 and reaches the bottom of the embossing roll 9. During this movement, the heater 10
Since it has been heated and softened by the embossing roll 9, when it passes under the embossing roll 9, the embossed pattern on the roll surface of the roll 9 is transferred to the outer surface. The foam sheet 1A having an embossed pattern is introduced into a guide tube 12 (a cross section is shown in FIG. 2). Since the foam sheet 1A is obtained by cutting open the foam tube 1, it enters the guide tube 12 while receiving the restoring force of the tube shape due to the shape memory effect of the crosslinked resin foam. While passing through the guide tube 12, the foam sheet 1A that has entered the guide tube 12 is shaped into a foam tube as shown in FIG. It almost restores to the shape of 1. The retractable tube-shaped foam 1B that has passed through the guide tube 12 is heated and melted at the seam portion by a hot air heater 13, and then guided to a belt-type tube forming device 14. This cylinder forming device 14
As shown in FIG. 3, the upper belt 15 and the lower belt 16 each have a molded surface close to a semi-cylindrical surface, so that the heated and melted joints of the open tube-shaped foam 1C are pressed against each other. , and are fused while passing through the cylinder forming device 14.

Thus, a product tube 1C, which is substantially dimensionally identical to the foam tube 1 extruded from the extruder 2, but with an embossed pattern and covered with a reinforcing or decorative film, is produced in a continuous line. be done.

As described above, according to the present invention, a foam extruded into a tube shape is once opened to form a sheet body, this sheet body is subjected to surface treatment, and then retubed to form a tube shape foam. By restoring it, the shape memory effect of the resin foam can be used to perform the re-tubing process, so it is possible to improve the roundness and achieve the desired shape compared to the conventional method. It is possible to obtain a foam tube that has undergone surface treatment, and since the process from foam extrusion to re-tubing is performed in-line, production efficiency can be greatly increased compared to conventional methods.

[Brief explanation of drawings]

FIG. 1 is a flow diagram of a production line for explaining an embodiment of the present invention, FIG. 2 is a sectional view of the guide tube in FIG. 1, and FIG. 4a and 4b are a perspective view of the foam sheet and a cross-sectional view of the open tube foam in FIG. 1, respectively. 1... Foam tube, 1A... Foam sheet, 1C... Product tube, 2... Extrusion molding machine,
3...Tube laparotomy cutter device, 4...Guide rod, 4a...Shape guide section, 5...Cutter, 7
... Take-up roll, 8 ... Roll for film pressure, 9 ... Roll for embossing, 10 ... Heater, 11 ... Reinforcement or decorative film, 1
2...Guide pipe, 13...Hot air heater, 14...
... Belt type tube forming device, 15, 16... Belt.

Claims (1)

[Claims] 1. A thermoplastic resin foam tube that is extruded into a tube shape and travels is guided into a sheet shape while being cut open on the travel path, and the foam that has become a sheet is supported on the travel surface by a predetermined distance to form a sheet. After running with the body intact, the shape is restored to the shape of an open tube, the open part of the foam with the restored shape is heated and thermally bonded, and when the running surface is supported, embossing and/or reinforcing or decorative films are crimped. A method for producing a surface-treated foam tube, characterized by applying the treatment to the surface of the foam.