JPH081787A - Mutuall bonding of side surfaces of cylindrical bodies - Google Patents

Abstract

PURPOSE:To make the area of a bonded part constant and to stably obtain a bonded object having good appearance and constant quality by flatening a plurality of flexible cylindrical bodies having an almost circular dross-sectional shape to make the contact parts thereof constant before welding the cylindrical bodies. CONSTITUTION:The distance between horizontal rolls 6a, 6b is made smaller than the outer diameter of tubes 1a, 1b to press and flatten the tubes. The horizontal rolls 6a, 6b and vertical rolls 7a, 7b are rotated to bring the plate- shaped heater 5 positioned at the central part between the vertical rolls 7a, 7b into contact with the contact part 4 of the tubes 1a, 1b and the heater 5 is heated to 200 deg.C to fuse the contact part 4 to bond the tubes 1a, 1b. Next, the bonded tube is passed through the gap between a pair of the rotary vertical rolls 8a, 8b arranged in opposed relationship on the left and right sides of the peripheral direction of the tubes 1a, 1b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a substantially circular cross section.
The present invention relates to a method of adhering side surfaces of a tubular body having flexibility.

[0002]

2. Description of the Related Art A plurality of (usually two) cylindrical bodies having a substantially circular cross-section, such as a thermoplastic resin tube or a rod-shaped body, are bonded to each other in parallel with their side surfaces. The joined body is used, for example, as a heat-insulating pipe for a copper pipe for air conditioning. In the production of the above joined body, a tube made of a thermoplastic resin as a tubular body,
A conventional bonding method will be described by exemplifying a case where the two are bonded together. As shown in FIGS. 5 and 6, two cylindrical bodies 1a and 1b are arranged in parallel on the base 2 and the Is sandwiched between a pair of vertical rolls 3a and 3b, and at this time, the distance between the pair of vertical rolls 3a and 3b is made smaller than the sum of the outer diameters of the tubular bodies 1a and 1b. 1
A method has been known in which a and 1b are brought into contact with each other and pressed, and the contact portion 4 is brought into contact with, for example, a plate heater 5 so as to be heat-sealed.

[0003]

However, in the above method, when the two cylindrical bodies 1a and 1b are sandwiched between a pair of vertical rolls 3a and 3b and pressed, the two cylindrical bodies are pressed. 1a and 1b are excessively deformed, the area of the contact portion between their side surfaces becomes too large, and in the joined body after heat fusion, the inside of the tubular body is not circular as shown in FIG. The upper and lower parts may peel off and the appearance may deteriorate, or the two tubular bodies may be torn apart when the joined body is used. At that time, the tubular bodies do not peel off between the tubular bodies. There were problems such as the device itself being torn.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a flexible bonding method for bonding side surfaces of a cylindrical body having a substantially circular cross section. The object is to provide a method for making the area of the surface constant.

[0005]

A method for adhering side faces of a tubular body according to the present invention is a method of adhering side faces of a tubular body having a substantially circular cross section and having flexibility. The cylindrical bodies are arranged so that their central axes are substantially parallel to each other, and the centers of the cross sections of one cylindrical body and the cross section of the other cylindrical body, which are adjacent to each other or close to each other. The cylindrical bodies are compressed from the direction perpendicular to the straight line connecting them to flatten the cylindrical bodies, and in the flattened state, the cylindrical bodies are inserted from both sides of the straight line. While pressing the bodies against each other, the side surfaces including a part of the straight line of each of the tubular bodies are heat-sealed to each other.

The cylindrical body used in the present invention has a substantially circular cross section, and examples thereof include a tube and a rod-shaped body.

The tubular body is flexible, and is preferably flexible enough to be bendable by hand, and is preferably elastically recoverable.

A thermoplastic resin is preferable as the material of the cylindrical body, for example, polyethylene, polypropylene,
Examples thereof include polyvinyl chloride. The tubular body may be a foamed body in addition to the usual non-foamed one. Polyethylene foam is particularly preferred as the foam.

In the method for adhering the side faces of the tubular body of the present invention, "cross sections adjacent to each other" means that when one side face of one tubular body and the side faces of the other tubular body are brought into contact with each other, In the relationship between the cross-section of the tubular body and the cross-section of the other tubular body, the cross-sections that are adjacent to each other and contact each other. When the side surfaces of the body are brought into contact with each other, in the relationship between the cross section of one tubular body and the cross section of the other tubular body, they are not adjacent to each other, but slightly in the longitudinal direction of the tubular body. A cross section that is separated.

As a concrete example of the method for adhering the side surfaces of the tubular body of the present invention, for example, between the pair of horizontal rolls in which the adjacent tubular bodies are vertically opposed and arranged, After arranging so that the center axes of the bodies are substantially parallel to each other, it is further sandwiched between a pair of vertical rolls, which are positioned facing each other on the left and right of each of the tubular bodies, and between the pair of vertical rolls. Set the distance
After setting such that the side surfaces of the tubular bodies have a desired contact area when the tubular bodies are flattened by being compressed from the vertical direction by the pair of upper and lower horizontal rolls. A method may be mentioned in which the distance between the pair of upper and lower horizontal rolls is made smaller than the outer diameter of each tubular body, and each tubular body is compressed in the vertical direction.

In the above compression operation, the outer diameters of the cylindrical bodies are not made to be the same but different diameters are used, and the respective cylindrical bodies are separated from each other between a pair of upper and lower horizontal rolls. It is also possible to sandwich it between and compress.

[0012]

Operation: Adjacent tubular bodies are arranged so that their central axes are substantially parallel to each other, and the cross sections of one tubular body and the other tubular body are adjacent to each other or mutually. Since the tubular bodies are flattened by compressing the tubular bodies in the vertical direction in the respective cross-sections with respect to the straight line connecting the centers of the cross-sections close to each other, the radius of curvature of the side surface of each tubular body is reduced. Is small, and the contact area can be reduced when the respective cylindrical bodies are brought into contact with each other. Further, when the respective tubular bodies are pressed against each other from both sides of the straight line, since the respective tubular bodies are flattened, the resistance of each tubular body against the compressive force becomes large, and it becomes difficult to dent. It becomes easy to control the contact area constant. Therefore, according to the method for adhering the side surfaces of the cylindrical body of the present invention, the area of the adhering portion can be made constant.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. For convenience of description, the same members as those in the conventional example shown in FIGS. 5 and 6 are designated by the same reference numerals. FIG.
FIG. 2 is a schematic side view showing an embodiment of the bonding method of the present invention, and FIG. 2 is a view taken along the line II-II of FIG. Two foamed polyethylene tubes (outer diameter 35 mm, inner diameter 10 mm, wall thickness 12.5 mm, foaming ratio 30 cc / g) 1a and 1b having a circular cross section were used as the bonded cylindrical bodies. At the time of bonding, the tubular bodies 1a and 1b were advanced in the arrow direction of FIG.

First, the tubular bodies 1a and 1b are passed between a pair of horizontal rolls 6a and 6b which are vertically opposed to each other so that their central axes are substantially parallel, and then the tubular body 1 is provided.
The rolls a and 1b were passed between a pair of vertical rolls 7a and 7b arranged facing each other in the circumferential direction. In addition, a pair of horizontal rolls 6a and 6b and a pair of vertical rolls 7
A roll-to-roll distance adjusting device (not shown) for adjusting the distance between the pair of rolls is attached to each of a and 7b. At this time, the distance between the pair of vertical rolls 7a and 7b is made flat by making the distance between the pair of horizontal rolls 6a and 6b smaller than the outer diameter of the tubes 1a and 1b. When set, the cross sections of the tubes 1a and 1b are set to contact each other over a desired width. A pair of vertical rolls 7a, 7
If the distance between b is too short, when the tubes 1a and 1b are deformed, the cross sections of the tubes 1a and 1b contact each other too much, so that the desired bonded body cannot be obtained, and if too long, the tubes 1a and 1b When 1b is flattened, the cross-sections of tubes 1a and 1b do not touch each other. In this embodiment, the vertical roll 7a,
The distance between 7b was 83 mm.

Next, the distance between the horizontal rolls 6a and 6b is made smaller than the outer diameter of the tubes 1a and 1b, and the tubes 1a and 1b are pressed to be flat. Specifically, the distance between the horizontal rolls 6a and 6b is set to 28 mm,
When the tubes 1a and 1b were flattened, the cross sections of the respective tubes became elliptical and contacted each other over the width of about 5 mm of the cross section of each tube, and the contact portion 4 was made constant.

Next, the horizontal rolls 6a and 6b and the vertical rolls 7a and 7b are rotated to rotate the tubes 1a and 1b.
While advancing b in the direction of the arrow in FIG. 1, the plate-shaped heater 5 located in the central portion between the vertical rolls 7a and 7b,
The tubes 1a and 1b were brought into contact with each other and heated to a temperature of 200 ° C. to fuse the tubes 4a and 1b together.

Next, the bonded tubes 1a and 1b are arranged in a pair of rotating vertical rolls 8a and 8b which are arranged to face each other in the circumferential direction of the tubes 1a and 1b.
(Note that the roll 8b exists on the back side of the roll 8a in FIG. 1). At this time, the distance between the pair of vertical rolls 8a and 8b was set shorter than the longest outer diameter of the cross section of the joined body of the tubes 1a and 1b. In particular,
The distance between the pair of vertical rolls 8a and 8b was 70 mm. In this way, by making the distance between the pair of vertical rolls 8a and 8b shorter than the longest outer diameter of the cross section of the joined body, the two tubes 1a and 1b that were formed into an elliptical shape at the time of fusion bonding are left and right. It was pressed from and returned to a circular shape.

By the above operation, the two tubes 1a and 1b each had a substantially circular cross section, and a bonded body in which the bonding area was limited to a desired area was obtained.

In the above-mentioned embodiment, the vertical rolls 8a and 8b are provided so that the tubes forming the joined body have a circular cross section. If it is not necessary to make it circular, this roll need not be provided.

Further, in the above embodiment, the pair of horizontal rolls 6a and 6b and the pair of vertical rolls 8a and 8b are used.
As the above, one set is used for each, but one set may be provided for each, or two or more sets may be provided.

When the tubes 1a and 1b are flattened, the sections of the tubes 1a and 1b come into contact with each other over a desired width, and the contact portions 4 of the tubes 1a and 1b contact each other during fusion. In addition to the pair of vertical rolls 7a, 7b that also act so as not to separate, in the vicinity of the pair of vertical rolls 7a, 7b, one pair or two or more pairs of vertical rolls are used, Roll 7
It is also possible to assist the action of a and 7b (for example, a pair of vertical rolls 9a and 9b shown in FIG. 3 is used. Note that the roll 9b exists on the back side of the roll 9a in FIG. The distance between the pair of vertical rolls 9a, 9b was set to 83 mm in this example).

Further, in the above-mentioned embodiment, two flexible cylindrical members each having a substantially circular cross section are adhered.
It is also possible to bond three or more pieces in the same manner.

FIG. 4 is a schematic sectional view showing another embodiment of the present invention. In this embodiment, the cylindrical bodies 11a and 11b to be bonded have different outer diameters. In this case, the cylindrical body 11 having the larger outer diameter
b is a pair of horizontal rolls 1 which are arranged vertically facing each other.
The cylindrical body 11a having a smaller outer diameter that is pressed by the 2a and 12b is pressed by a pair of horizontal rolls 13a and 13b that are vertically opposed to each other, and the cylindrical bodies 11a and 11b are left and right in the circumferential direction. The pressing force was applied by a pair of vertical rolls 14a and 14b. In this way, a joined body could be obtained even with tubular bodies having different diameters.

[0024]

The structure of the method for adhering the side faces of the tubular body of the present invention is as described above, and each of the plurality of flexible tubular bodies having a substantially circular cross section is flattened. After the contact portion is made constant by fusing the contact portion, the area of the adhesive portion can be made constant, and the joined body having good appearance and constant quality can be stably obtained.

[Brief description of drawings]

FIG. 1 is a schematic side view showing an embodiment of a bonding method of the present invention.

FIG. 2 is a view taken along the line II-II of FIG.

FIG. 3 is a schematic side view showing another embodiment of the bonding method of the present invention.

FIG. 4 is a schematic cross-sectional view showing another embodiment of the bonding method of the present invention.

FIG. 5 is a schematic side view showing a conventional bonding method.

6 is a view taken along the line VI-VI of FIG.

FIG. 7 is a cross-sectional view showing an example of a conventional bonded body.

[Explanation of symbols]

 1a, 1b Cylindrical body 4 Contact part 5 Plate heater 6a, 6b Horizontal roll 7a, 7b Vertical roll

Claims (1)

[Claims] 1. A cross section having a substantially circular shape and flexibility.
In the bonding method of the side surfaces of the tubular body, adjacent tubular bodies are arranged so that their central axes are substantially parallel to each other, and a cross section of one tubular body and a cross section of the other tubular body, The tubular bodies are flattened by compressing the tubular bodies in a direction perpendicular to the straight lines connecting the centers of the cross-sections adjacent to each other or the cross-sections close to each other to flatten the tubular bodies. In a tubular body characterized in that the side surfaces including a part of the straight line of each tubular body are heat-sealed to each other while mutually pressing the tubular bodies from both sides of the straight line in the state of being Adhesion method between sides.