JP2005172088A - Connecting structure of resin pipe and its connecting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a connecting structure of resin pipes and its connecting method without leakage even when used with gas, which hardly slips off even under a high pressure, capable of drastically enhancing reliability, easily connectable even upon use of a multiple layered tube, and which hardly causes leakage while maintaining the characteristic of a multiple layered tube, thereby enhancing reliability. <P>SOLUTION: 1 denotes a tube with a single layered or a multiple layered structure made of thermoplastic resin material, 2 a joint equipped with a nipple part 3 made of thermoplastic resin material, and an end 1a of the tube 1 is press-fitted to the outside of the nipple part 3 of the joint 2 and connected to be integrally structured. In the first embodiment of this invention, a boundary joint face X of the end 1a of the tube 1 and the nipple part 3 of the joint 2 is fusion-bonded to be integrally structured. As the means for this fusion bonding, a general fusion-bonding means can be used, but in the embodiment of this invention, a laser device 4 is used from the outside of the part which is fitted and connected. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a resin pipe connection structure and a connection method thereof, and more specifically, a resin pipe connection structure in which a boundary joint surface between a tube end portion and a joint nipple portion is melt-bonded and integrally formed, and its It relates to a connection method.

  Conventionally, the structure of resin joints is to seal by fitting one end of the tube with an O-ring interposed in the nipple of the joint, and to prevent the tube from coming off, it is hooked on an uneven ridge formed on the nipple of the joint. (For example, refer to Patent Document 1). Such a resin joint structure is a joint used for liquids such as gasoline and alcohol, and can be used because the pressure is relatively low. However, when such a resin joint is used for a high-pressure gas pipe, the performance against gas leakage and disconnection is insufficient and the reliability is low.

  As another conventional resin joint structure, there has also been proposed a method in which the end faces of two fluororesin pipes and joints are heated with infrared rays and bonded to each other (see, for example, Patent Document 2). ). However, such a joint method is a method in which the end face of the shaft or the thick end face is butted and joined, so that it is difficult to join thin film tubes.

  Also, in recent years, the characteristics required for piping have become complicated, and piping materials have chemical stability to the fluid to be used, quantity characteristics of component extraction from the piping material to fluid, characteristics of fluid component permeation, It is required to satisfy the required specifications such as pressure strength against internal pressure and temperature characteristics. In order to satisfy these required specifications, pipes are multi-layered.

Further, in the case of tube-like piping, the end face when it is multi-layered becomes a plurality of types of resins, so that melt bonding becomes difficult for the following reasons.
(A). Multiple materials have different melting points and high infrared absorption frequencies, and it is difficult to simultaneously bring each resin material into a molten state suitable for bonding.
(B). It is often necessary to use a film-like layer because of the specifications such as the above required characteristics, material cost constraints, and pipe flexibility.
JP 2002-228087 A Japanese Patent Publication No. 3-43054

  The present invention pays attention to such a conventional problem, and since the boundary joint surface between the tube and the joint is integrally formed by fusion bonding, there is no leakage even if it is used for gas, and it is difficult to come out even if the pressure becomes high. The reliability of the resin piping that can remarkably increase the reliability and can be easily joined even when the multilayer tube is used, and it is difficult to leak while maintaining the characteristics of the multilayer tube. It is an object of the present invention to provide a connection structure and a connection method thereof.

  In order to achieve the above object, the present invention provides a resin pipe connection structure according to the present invention, wherein the tube end part and the joint nipple part are press-fitted and joined to each other. The gist is that the boundary joint surface between the terminal portion and the nipple portion of the joint is integrally formed by melting and bonding.

  Further, according to another connection structure of the resin pipe of the present invention, the tube and the joint are formed of a resin material that transmits laser light or a resin material that absorbs laser light, and the end portion of the tube and the nipple portion of the joint At the time of press-fitting, the laser beam is arranged so that at least the laser beam irradiation side is a resin material that transmits the laser beam, and the boundary junction surface between the end portion of the tube and the nipple portion of the joint is irradiated with the laser beam from the laser device. The gist is that they are integrally formed by irradiation and melt bonding.

  Here, the tube is configured in a multilayer structure made of different materials, and the boundary joint surface between the end portion of the tube and the nipple portion of the joint is configured to be the same material, and the end portion of the tube and the joint At least one of the boundary joint surfaces with the nipple portion is formed in an uneven surface shape.

  It is also possible to interpose a sleeve that absorbs laser light between the boundary joint surfaces between the end portion of the tube and the nipple portion of the joint, and the resin material that absorbs laser light contains carbon black. It is also possible to add a dye or pigment that absorbs visible light and transmits infrared light to at least one of the tube and the joint. When the tube has a multilayer structure, the innermost layer surface is formed of a fluororesin.

  As described above, since the boundary joint surface between the tube and the joint is integrally formed by melting and bonding, there is no leakage even if it is used for gas, and it is difficult to come out even at high pressure, so the reliability can be remarkably enhanced. Is.

  Further, the resin pipe connection method of the present invention is such that when the tube end portion and the nipple portion of the joint are press-fitted, press-fitting is performed such that the laser light irradiation side is a resin material that transmits the laser light, The gist of the present invention is that the boundary joining surface between the joint and the nipple portion of the joint is melted by irradiating a laser beam from a laser device to melt the boundary joining surface integrally.

  In this way, the boundary joint surface between the end portion of the tube and the nipple portion of the joint is melted by irradiating laser light from a laser device, and the boundary joint surface is integrally welded, so that it can be used for gas. There is no leakage, it is difficult to come out even at high pressure, and the reliability can be remarkably improved. It can be easily joined even when a multilayer tube is used, and leakage is maintained while maintaining the characteristics of the multilayer tube. It is difficult and can improve reliability.

Since the present invention integrally forms the boundary joint surface between the tube and the joint by melting and bonding as described above, the following excellent effects can be obtained.
(a) There is no leakage even if it is used in gas, and it is difficult to come out even at high pressure, and the reliability can be remarkably improved.
(b) It is possible to easily join even when a multi-layer tube is used, and it is difficult to leak while maintaining the characteristics of the multi-layer tube, and the reliability can be improved.
(c) Since a conventional sealing member such as an O-ring is not required, impurities such as plasticizers contained in the rubber material are not extracted into the fluid, which may adversely affect the apparatus using the piping. No.
(d). Since the laser device is a conventional laser device, it is possible to perform a safe operation, to easily and efficiently produce the equipment, and to reduce the cost.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a half sectional view of a resin pipe connection structure showing a first embodiment of the present invention, wherein 1 is a single-layer or multilayer tube made of a thermoplastic resin material, and 2 is a nipple made of a thermoplastic resin material. The joint provided with the part 3 is shown, and the end part 1a of the tube 1 is press-fitted into the outside of the nipple part 3 of the joint 2 and joined to form an integral part.

  In the first embodiment of the present invention, the boundary joint surface X between the end portion 1a of the tube 1 and the nipple portion 3 of the joint 2 is integrally formed by fusion bonding.

  As the means for melting and bonding, a general melting means can be used, but in the embodiment of the present invention, one selected from a known semiconductor laser, solid laser, gas laser, etc. from the outside of the joined joint. One laser device 4 is selected and used. As a condition in this case, the tube 1 and the joint 2 are made of a transparent thermoplastic resin material that transmits the laser beam Q, or absorbs the laser beam Q (it is difficult to transmit the laser beam). For example, a black thermoplastic resin Form each with material.

  The number of laser devices 4 is not limited to one, and a plurality of laser devices can be used, and the position where the laser beam Q is irradiated is the boundary between the terminal portion 1a of the tube 1 and the nipple portion 3 of the joint 2. The whole or part of the bonding surface X is irradiated.

  And when the end portion 1a of the tube 1 is press-fitted into the nipple portion 3 of the joint 2 and fitted, at least the side that irradiates the laser beam Q is disposed so as to be a resin material that transmits the laser beam Q, The boundary joint surface X between the end portion 1a of the tube 1 and the nipple portion 3 of the joint 2 is integrally formed by irradiating the laser beam Q from the laser device 4 and melt-bonding it.

  For example, in the first embodiment of FIG. 1, the end portion 1 a of the tube 1 is press-fitted into the nipple portion 3 of the joint 2 to be fitted, and the tube 1 is transparent thermoplastic resin material that transmits the laser beam Q. The joint 2 is made of a black thermoplastic resin material that absorbs the laser light Q.

  In the case of the second embodiment shown in FIG. 2, the end portion 1a of the tube 1 is press-fitted into the inside of the nipple portion 3 of the joint 2 so that the joint 2 is connected to the laser beam Q in this case. The tube 1 is formed of a black thermoplastic resin material that absorbs the laser light Q.

  In the first embodiment of FIG. 1, when laser light Q is irradiated from the laser device 4 to the boundary joint surface X between the terminal portion 1 a of the tube 1 and the nipple portion 3 of the joint 2, the thermal energy of the laser light Q is changed to the tube 1. The nipple portion 3 of the joint 2 is heated through the end portion 1a of the joint 2 and the thermal energy is transmitted to the end portion 1a of the tube 1 so that the boundary joint surface X between the joint 2 and the end portion 1a of the tube 1 is melted. Will be melted and bonded.

  In addition, in order for the boundary joint surface X of the terminal part 1a of the tube 1 and the nipple part 3 of the joint 2 to fuse | melt reliably, is the terminal part 1a of the tube 1 and the nipple part 3 of the joint 2 closely_contact | adhered? The gap needs to be 0.05 mm or less, but the end portion 1a of the tube 1 and the nipple portion 3 of the joint 2 are press-fitted as described above, so that the gap can be closely attached.

  Further, when a hard resin tube is used, it is assumed that the adhesion is deteriorated at the time of fitting. In this case, for example, the outer side of the nipple portion 3 of the joint 2 in FIG. A step 5 is provided, and the end portion 1a of the tube 1 is press-fitted into the outside of the nipple portion 3 of the joint 2 so as to be joined, and a half sectional view showing another embodiment and the inside of the nipple portion 3 of the joint 2 in FIG. As shown in the semi-sectional view showing another embodiment in which the step portion 5 is formed in an uneven surface shape and the end portion 1a of the tube 1 is press-fitted into the inside of the nipple portion 3 of the joint 2 and joined, By providing the step 5 in which the boundary joint surface X of the nipple part 3 is formed in a concavo-convex surface shape, the contact pressure at the boundary joint surface X can be increased, thereby improving the quality and reliability of the connection part. Become.

  It is also possible to provide a step on the outer surface of the tube 1 so as to achieve the same effect as described above.

  Since other configurations and operations are the same as those in the first embodiment, the same reference numerals are given and description thereof is omitted.

  Further, a sleeve 6 formed of a resin material that absorbs laser light Q is interposed between the boundary joint surface X between the end portion 1a of the tube 1 and the nipple portion 3 of the joint 2 in FIG. Is inserted into the outside of the nipple portion 3 of the joint 2 and is joined in a semi-sectional view, or between the boundary joint surface X between the end portion 1a of the tube 1 and the nipple portion 3 of the joint 2 shown in FIG. A half-sectional view showing another embodiment in which a sleeve 6 made of a resin material that absorbs laser light Q is interposed and the end portion 1a of the tube 1 is press-fitted inside the nipple portion 3 of the joint 2 and joined. As described above, the sleeve 6 for absorbing laser light is fitted between the interface 1 between the end portion 1a of the tube 1 and the nipple portion 3 of the joint 2, and the laser device 4 is fitted to the sleeve 6 portion. Irradiated with laser light Q That when, in the sleeve 6 by the thermal energy of the laser light Q is melted and the boundary joining surface X of the terminal portion 1a and the nipple portion 3 of the joint 2 of the tube 1 can be hot-melt adhesive.

  In this embodiment, the tube 1 and the joint 2 are both made of a transparent thermoplastic resin material through which the laser beam Q is transmitted, or a transparent heat through which the laser beam Q is transmitted on the side irradiated with the laser beam Q. A tube 1 or a joint 2 made of a plastic resin material is provided.

  Since other configurations and operations are the same as those in the first embodiment, the same reference numerals are given and description thereof is omitted.

  By adopting such a resin piping connection structure, the end portion 1a of the tube 1 and the nipple portion 3 of the joint 2 can be manufactured with a resin material free of contaminants, and as a result, used for applications where impurities are hated. In doing so, the extract from the piping material can be prevented from being mixed into the fluid.

  Furthermore, as a material for absorbing the laser light of the tube 1, the sleeve 6 and the joint 2 in each of the above embodiments, by adopting carbon black, the laser light absorption rate is high, efficient, and inexpensive. There is an advantage that can be manufactured. In addition, when a dye or pigment that absorbs visible light and transmits infrared light is added to the tube 1 or the joint 2, a tube having a wavelength in the infrared region, such as a YAG laser, is used without impairing the fusibility. The color of 1 can be set arbitrarily, and the visibility can be enhanced even when used in an apparatus used for many pipes.

  In the above embodiments, the tube 1 is described as a single-layer tube or a multi-layer tube connection structure. However, in the case of a single-layer (one type of resin) tube, a laser device is not particularly used. It is possible to melt and bond the joint 2 with another fusing device or the like. However, as shown by the dotted lines in FIG. 1 and FIG. 2, when the innermost layer and the outermost layer of the tube 1 have a multi-layer structure formed of different resin materials 1x, it is difficult to join the pipes with the conventional fusion device, and the seal The reliability such as the property is also low.

  In particular, when a joint is manufactured using a material based on the same fluororesin as the innermost layer of the tube 1 and added with a material that absorbs laser light, the surface in contact with the fluid should be made of only the fluororesin. Thus, the multilayer tube can be easily melt-bonded.

  As described above, the boundary bonding surface X between the end portion 1a of the tube 1 and the nipple portion 3 of the joint 2 is melted by irradiating the laser beam Q from the laser device 4 so that the boundary bonding surface X is integrally melt bonded. By doing so, there is no leakage even if it is used for gas, it is difficult to come out even at high pressure, and the reliability can be remarkably improved, and it is possible to easily join even when using a multilayer tube, It is difficult to leak while maintaining the characteristics of the multilayer tube, and the reliability can be increased.

It is a half section view of the state where the end of the tube showing the first embodiment of the present invention was pressed and joined to the outside of the nipple portion of the joint. It is a half sectional view of the state where the end part of the tube which shows a 2nd embodiment of this invention was made to press fit inside the nipple part of a joint, and was joined. FIG. 10 is a half sectional view showing another embodiment in which the outer side of the nipple part of the joint is formed in an uneven surface shape to provide a step, and the end part of the tube is press-fitted into the outer side of the nipple part of the joint and joined. FIG. 10 is a half cross-sectional view showing another embodiment in which the inner side of the nipple portion of the joint is formed into a concavo-convex surface to provide a step, and the end portion of the tube is press-fitted inside the nipple portion of the joint and joined. In addition to interposing a sleeve made of a resin material that absorbs laser light between the boundary joint surface between the end of the tube and the nipple of the joint, the end of the tube is press-fitted outside the nipple of the joint and joined together It is a half sectional view showing an embodiment. In addition to interposing a sleeve made of a resin material that absorbs laser light between the boundary joint surface between the end of the tube and the nipple of the joint, the end of the tube is pressed into the inside of the nipple of the joint and joined. It is a half sectional view showing an embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Tube 1a End part of tube 2 Joint 3 Nipple part 4 Laser apparatus 5 Level | step difference 6 Sleeve X Boundary interface Q Laser beam

Claims (9)

A resin pipe connection structure formed by press-fitting and joining a tube end portion and a joint nipple portion,
A resin pipe connection structure characterized in that a boundary joint surface between a terminal portion of the tube and a nipple portion of a joint is integrally formed by fusion bonding. The tube and the joint are formed of a resin material that transmits laser light or a resin material that absorbs laser light. At the time of press-fitting between the end portion of the tube and the nipple portion of the joint, at least the laser light irradiation side is a laser. It is arranged so that it becomes a resin material that transmits light, and the boundary joint surface between the end portion of the tube and the nipple portion of the joint is integrally formed by irradiating a laser beam from a laser device and melt-bonding it. Characteristic resin piping connection structure. 3. The resin pipe connection structure according to claim 2, wherein the tube is formed in a multilayer structure made of different materials, and a boundary joint surface between the end portion of the tube and the nipple portion of the joint is made of the same material. The resin pipe connection structure according to claim 2 or 3, wherein at least one of the boundary joint surfaces between the end portion of the tube and the nipple portion of the joint is formed in an uneven surface shape. The resin pipe connection structure according to claim 2, 3 or 4, wherein a sleeve for absorbing laser light is interposed between boundary joint surfaces between the end portion of the tube and the nipple portion of the joint. The resin pipe connection structure according to claim 2, 3 or 4, wherein the resin material that absorbs the laser light contains carbon black. The resin pipe connection structure according to claim 2, 3 or 4, wherein a dye or pigment that absorbs visible light and transmits infrared light is added to at least one of the tube and the joint. The resin pipe connection structure according to claim 2, 3, 4, 5, 6 or 7, wherein the innermost layer surface is formed of a fluororesin when the tube has a multilayer structure. At the time of press-fitting between the tube end and the fitting nipple, press-fit so that the laser light side is a resin material that allows the laser beam to pass through, and enter the boundary interface between the tube end and the fitting nipple. A method for connecting resin pipes, characterized in that a laser beam is irradiated from a laser device to melt and a boundary joint surface is integrally melt-bonded.

Images