JPH06328555A - Bending method and device for synthetic resin pipe for bending - Google Patents

Abstract

PURPOSE:To soften a part and provide a processing method and a device for bending the part easily by using a synthetic resin pipe for bending manufactured by molding integrally a high frequency induction heat developing layer and a thick wall section of a pipe for the purpose of forming the synthetic resin pipe for performing the bending easily and heating the heat developing layer of the pipe. CONSTITUTION:A synthetic resin pipe 10 suitable for bending is used, and the heating of a bending section N is applied by emitting high frequency magnetic field positioned close to a high frequency magnetic field generating device E to a heat developing layer 2 formed on the bending section. The high frequency magnetic field of the high frequency magnetic field generating device is emitted to the heat developing layer formed in the middle of a pipe by the arrangement, and the bending of the bending part can be performed easily by heat softening the part only.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for bending a synthetic resin pipe for bending and an apparatus therefor. The inventor of this application is an inventor of a synthetic resin pipe for bending,
About this tube
The application is disclosed on the 6th of a month). The present invention intends to perform bending by applying a high frequency induction heating method to the above-mentioned tube.

[0002]

2. Description of the Related Art Thermoplastic synthetic resin pipes are heat set (heat molded) into various shapes and used in the following manner. For example, a coiled tube made by heat setting nylon and polyurethane tubes (pipes) is used as a hose for industrial, mechanical or air tools, a tube that has been bent in two or three dimensions is used as a fuel tube for automobiles, or Used as a pipe for other industrial parts.

In all of the bending methods for the above-mentioned pipes, the entire pipe or tube is preheated or heated to a required temperature, and under this heating condition, bending or the like is performed, and then a desired shape is obtained through a cooling means. Was getting the product. As the heating catalyst, gas, fluid, or solid (sand, mold) has been used.

[0004]

The conventional bending process is shown in FIG.
As shown in (a), the pipe 1'is heated by a heating device H ', and this is pushed into a mold M'shown in (b) to form two bent portions N', N ', and thereafter the mold is formed. Pipe 1'containing M '
The whole was cooled to manufacture the crank type pipe shown in (c).

As described above, in the conventional heat set, it is a matter of course that the two-dimensional and three-dimensional molding should be carried out, and the molding die (sand, mold, etc.) must be heated unless it is heated to the bent portion. However, there is a drawback that the entire die (bending device) that encloses the pipe must be cooled during cooling after molding.

The inventor of this application intends to effectively perform heat setting by using a bending synthetic resin tube which does not require a heating catalyst which has been conventionally required.

As shown in FIG. 9, the above-mentioned bending synthetic resin pipe has a tubular body 1 made of a thermoplastic synthetic resin, and the heat generating layer 2 has the same material as the molding material of the tubular body 1 not shown. The heating element is formed by kneading the above material and a metal heating material, and is designated by reference numeral 10.

[0008]

In order to achieve the above-mentioned object, the present invention heats a heating element in a bending portion of a bending synthetic resin tube by heating the heating element at this portion, and uses this heat as a catalyst. It is intended to soften only this part and perform two-dimensional or three-dimensional molding.

The basic method of the bending method will be described below with reference to FIG. As shown in (a), the high-frequency transmitters E, E are attached to the bent portions N, N of the pipe 10.
Is applied to heat the heating element in this region to weaken it, and then it is pushed into the mold M to form a crank mold as shown in (b), and thereafter only the bent portions N, N of the pipe 10 are formed. When (c) is cooled, the crank type pipe shown in (c) can be manufactured.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The high frequency transmitter used in the embodiment of the present invention will be described below with reference to FIG. FIG. 2 shows a basic device of a high-frequency transmitter as a conceptual diagram. The transmitter E is composed of an upper mold 3 and a lower mold 4 which can be opened and closed upward and downward. They are connected by 5, and both types are each given a free calling function. In addition, a desired cylindrical empty space C is provided inside both molds.
Are formed. Further, a publicly known high-frequency transmission device is selectively adopted as the both types of transmission means.

The following is a description of an embodiment in which bending is performed using the above high-frequency transmitter, with reference to FIGS. 3 and 4. First step, as shown in FIG. 3, bending synthetic resin tube 10
Position the bending part of the inside of the cylindrical chamber C of the high frequency device E,
This part is weakened by the heat generated by the heating element 2. In the second step, as shown in FIG. 4, the softening pipe is pushed into a bend forming mold M having a bent shape to form an L-shape.
After forming the L-shape, the mold is fixed via the cooling tool W.

Another embodiment of the present invention will be described below with reference to FIG. This embodiment shows a case where the invention is applied to a joint of a synthetic resin pipe. In FIG. 5, reference numeral 7 denotes a joint, and the heating element 2 is provided on the cylindrical wall of the joint body 1 of this joint, which has the same structure as that of the bending synthetic resin pipe described above.

When connecting the synthetic resin pipes 8, 8 made of the same material to the joint 7, high frequency transmission is performed with the respective tips of the connecting pipes 8, 8 inserted into the joint 7. The device E is actuated to heat the heating element of the joint body, and the heat melts the connecting portion, so that the joint body and the connecting pipe are welded and solidified.

Other Embodiments FIG. 6 shows a case where a coil ring tube is formed.
The synthetic resin tube 10 for bending is continuously heated and softened through the high frequency transmission device E, the winding drum mouth is operated, and the tube 10 is wound in a coil shape on the drum surface, and after molding. The coil ring tube K can be manufactured by quenching.

By using this method together, it is possible to form a two-dimensional or three-dimensional bent pipe. FIG. 7 shows a case of a large-diameter wall tube. In this case, as shown in the figure, two heating layers 2 and 2 (heating elements) are formed within the wall thickness of the tube body 1. The high-frequency transmitters E, E provided on the outer side and the inner side of the bending synthetic resin pipe 10 are operated to heat both the heating elements 2, 2 at the same time, and the thick portion of this portion is softened in a short time. Venting can be performed.

The present invention is not limited to the above-mentioned embodiment, and for example, flare processing of the tip of the pipe or bulging processing for forming a ridge in the middle portion of the pipe is desired by using a jig applicable to that purpose. You can get the product.

[0017]

As described above, according to the present invention, only a desired portion of a pipe is softened by a high-frequency transmitting device for a bending synthetic resin pipe in which a heat generating layer is integrally molded at an intermediate portion of the synthetic resin pipe. Since a desired mold can be obtained by freely bending and solidifying only this portion by cooling, workability can be improved as compared with conventional bending.

[Brief description of drawings]

FIG. 1 is a flow sheet of a processing method of the present invention.

FIG. 2 is an explanatory view of a main part of a high frequency transmitter according to the present invention.

FIG. 3 is an explanatory view of a method for bending a synthetic resin pipe for bending, which is a heating device thereof.

FIG. 4 is an explanatory view of a bending method of a bending synthetic resin pipe and a bending apparatus therefor.

FIG. 5 is a cross-sectional explanatory view of a main part when a bending synthetic resin pipe is applied to a joint.

FIG. 6 is an explanatory view of a method and apparatus for forming a bending synthetic resin tube into a coil ring tube.

FIG. 7 is an explanatory diagram of a tube structure and a heating means for heating a large diameter and large thickness tube of a bending synthetic resin tube.

FIG. 8 is an explanatory diagram of a conventional heat set.

FIG. 9 is an explanatory view of a bending synthetic resin tube.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 tubular body 2 heating layer (heating element) 3 upper mold 4 lower mold 7 joint 8 synthetic resin pipe for connection E high-frequency transmitter K coil ring tube N bent portion W cooling tool

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[Procedure amendment]

[Submission date] December 24, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] Full text

[Correction method] Change

[Correction content]

[Document name] Statement

Title: Method and apparatus for bending synthetic resin pipe for bending

[Claims]

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for bending a synthetic resin pipe for bending and an apparatus therefor. The inventor of this application is an inventor of a synthetic resin pipe for bending,
Regarding this tube, Japanese Patent Laid- Open No. 5-101891 (April 1993)
Application is disclosed on the 6th of a month) The present invention intends to perform bending by applying a high frequency induction heating method to the above-mentioned tube.

[0002]

2. Description of the Related Art Thermoplastic synthetic resin pipes are heat set (heat molded) into various shapes and used in the following manner. For example, a coiled tube made by heat setting nylon and polyurethane tubes (pipes) is used as a hose for industrial, mechanical or air tools, a tube that has been bent in two or three dimensions is used as a fuel tube for automobiles, or Used as a pipe for other industrial parts.

[0003] Any machining method bending for each tube described above was heated pipe, the entire tube to the preheat or required temperature, under the heating conditions, subjected to forming shape processing such as bending, desired shape through a subsequent cooling means Was getting the product. As the heating catalyst, gas, fluid, or solid (sand, mold) has been used.

[0004]

The conventional bending process is shown in FIG.
As shown in (a), the pipe 1'is heated by a heating device H ', and this is pushed into a mold M'shown in (b) to form two bent portions N', N ', and thereafter the mold is formed. Pipe 1'containing M '
The whole was cooled to manufacture the crank type pipe shown in (c).

[0005] As described above, the conventional heat set two-dimensionally, as the site to perform a three-dimensional formed shape course, forming shape mold to be heated up than the bending point (sand mold It is those that can not be set at equal). Before particular formed shape <br/> after cooling there is a disadvantage that must be cooled the whole mold (bending device) enclosing the pipe.

The inventor of this application intends to effectively perform heat setting by using a bending synthetic resin tube which does not require a heating catalyst which has been conventionally required.

As shown in FIG. 9, the above-mentioned bending synthetic resin pipe is made of a thermoplastic synthetic resin for the tubular body 1, and the high-frequency induction heating layer 2 is not particularly shown for molding the tubular body 1. For materials and high-frequency magnetic fields that have the same or compatibility with
Therefore, it is formed of a heating element kneaded with a heating material such as metal to be induction-heated, and is indicated by reference numeral 10.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a high-frequency wave in a bending portion of a bending synthetic resin pipe.
Magnetic field to heat the heating elements of the site by irradiating, the heat as the catalyst, a two-dimensional soften this site only, those wishing to make a three-dimensional formed shape.

The basic method of the bending method will be described below with reference to FIG. As shown in (a), a high-frequency magnetic field from the high-frequency magnetic field generators E, E is applied to the bent portions N, N of the pipe 10 to heat and weaken the heating element in this portion, and then the same. As shown in (b), the crank die is pushed into the die M to form a crank die, and then only the bent portions N, N of the pipe 10 are cooled, whereby the crank pipe shown in (c) can be manufactured.

[0010]

EXAMPLES are as follows will be described a high-frequency magnetic field onset raw <br/> apparatus used in an embodiment of the present invention by FIG. Figure 2 is a high-frequency basic device of the magnetic field onset generating device is intended as a conceptual diagram, on the occur device E, and a lower die 4 upper die 3 can be opened and closed under
The upper and lower molds are connected by a hinge part 5, and both molds generate a free magnetic field.
Has been given a raw function. Further, a desired cylindrical void C is formed inside the molds. Further, examples of both types of occur <br/> means, high-frequency magnetic field onset generating device publicly <br/> known with a high-frequency power source and a magnetic field generating coil is selectively employed.

[0011] is as follows if described with reference to FIGS. 3 and 4 an embodiment of a case of bending with the high-frequency magnetic field onset generating device. First step, as shown in FIG. 3, bending synthetic resin tube 10
The bent portion of the above is positioned in the cylindrical cavity C of the high-frequency magnetic field generator E, and this portion is weakened by the heat generated by the heating element 2. In the second step, as shown in FIG. 4, the softening pipe is pushed into a bend forming mold M having a bent shape to form an L-shape.
After forming the L-shape, the mold is fixed via the cooling tool W.

Another embodiment of the present invention will be described below with reference to FIG. This embodiment shows a case where the invention is applied to a joint of a synthetic resin pipe. In FIG. 5, reference numeral 7 denotes a joint, and the heating element 2 is provided on the cylindrical wall of the joint body 1 of this joint, which has the same structure as that of the bending synthetic resin pipe described above.

When connecting the synthetic resin pipes 8 and 8 made of the same material to the joint 7, the high frequency magnetic field is obtained with the respective tips of the connecting pipes 8 and 8 inserted into the joint 7. heating the heating element 2, 2 of the joint body by actuating the occurrence device E, to melt the connecting portion by the heat, and a joint body and the connecting tube welded shaped solidified connection can be obtained.

Other Embodiments FIG. 6 shows a case where a coil ring tube is formed.
Bending synthetic resin pipe 10 allowed to soften allowed continuous pressurization via a high-frequency magnetic field onset generating device E, actuates the winding drum D, wound the tube 10 in a coil shape to the drum surface, The coil ring tube K can be manufactured by quenching after molding.

By using this method together, it is possible to form a two-dimensional or three-dimensional bent pipe. FIG. 7 shows a case of a large-diameter wall tube. In this case, as shown in the figure, two heating layers 2 and 2 (heating elements) are formed within the wall thickness of the tube body 1. bending synthetic resin tube 10 of the outer and each high-frequency magnetic field onset generating device E provided inside, E
Is operated to heat both the heating elements 2 and 2 at the same time to soften the thick portion of this portion in a short time, and venting can be performed.

The present invention is not limited to the above-mentioned embodiment, and for example, flare processing of the tip of the pipe or bulging processing for forming a ridge in the middle portion of the pipe is desired by using a jig applicable to that purpose. You can get the product.

[0017]

EFFECTS OF THE INVENTION The present invention has a high level in the middle portion of a synthetic resin pipe.
By the high frequency magnetic field onset generating device relative to the integrally molded bending synthetic resin tube for processing frequency induction heating layer, is soft the desired site only of the tube, performs bending of this portion freely,
A desired mold can be obtained by cooling and solidifying only this portion, and workability can be improved as compared with conventional bending.

[Brief description of drawings]

FIG. 1 is a flow sheet of a processing method of the present invention.

2 is an explanatory view showing main components of a high-frequency magnetic field onset generating device according to the present invention.

FIG. 3 is an explanatory view of a method for bending a synthetic resin pipe for bending, which is a heating device thereof.

FIG. 4 is an explanatory view of a bending method of a bending synthetic resin pipe and a bending apparatus therefor.

FIG. 5 is a cross-sectional explanatory view of a main part when a bending synthetic resin pipe is applied to a joint.

FIG. 6 is an explanatory view of a method and apparatus for forming a bending synthetic resin tube into a coil ring tube.

FIG. 7 is an explanatory diagram of a tube structure and a heating means for heating a large diameter and large thickness tube of a bending synthetic resin tube.

FIG. 8 is an explanatory diagram of a conventional heat set.

FIG. 9 is an explanatory view of a bending synthetic resin tube.

[Reference Numerals] 1 tube 2 heating layer (heating element) 3 upper mold 4 for the lower mold 7 joint 8 connected plastic pipe E high-frequency magnetic field onset generating device K coil ring tube N bend W cooling device

Claims (2)

[Claims] 1. A synthetic resin tube for bending, in which a heat generating layer 2 is integrally molded in a tubular body 1, is heated by a high-frequency transmitter to heat only the portion to be bent, and the portion is softened. A bending method for a synthetic resin pipe for bending, characterized in that the bent pipe is pushed into a bending mold to perform bending, and immediately after that, this portion is cooled to perform bending. 2. A high frequency transmitter for use in the bending method according to claim 1.