JP2009078485A - Shaft body and writing utensil using the shaft body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the separation of joint portion of a shaft tube and the generation of looseness caused by the swelling with sweat in the shaft body formed with two or more shaft tubes each being inserted to and contacted with the other. <P>SOLUTION: In a shaft body formed with two or more shaft tubes each being inserted to and contacted with the other, at least one shaft tube is made of non-permeable resin which is opaque to a laser beam, and at least one shaft tube contacting the shaft tube is made of a permeable resin which is penetrable by a laser beam, and the contacting portion of these shaft tubes are welded and joined by the irradiation of a laser beam. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to the joining of a shaft body, particularly a shaft body provided with a gripping part, and examples of the shaft body include writing instruments such as ballpoint pens and mechanical pencils, elongated containers such as lipsticks and eyeliners, fishing rods, Examples include tools such as door knobs and drivers.

There are various means such as fitting, screws, bonding, thermal welding, ultrasonic welding, which are provided with concave and convex portions for locking, for joining the shaft cylinders forming the shaft body, and these are the purpose and strength of joining, Various inventions have been made from the viewpoint of man-hours and costs.
Japanese Utility Model Publication No. 59-122286 (Fitting with uneven portions: Mitsubishi) Japanese Utility Model Publication No.59-122285 (Screw: Mitsubishi) Japanese Utility Model Publication No. 3-29453 (thermal welding: Pentel) Japanese Utility Model Publication No. 3-103780 (ultrasonic welding: Mitsubishi)

However, if sufficient joint strength cannot be obtained due to material characteristics and structural restrictions, the joint portion may be detached or peeled off when the shaft is used, making it unusable. In particular, when an elastic resin is used for the gripping part or the like, the oil contained in the elastic resin inhibits the curing of the adhesive or weakens the activity of the adhesive component. There was a problem that smooth joining was difficult and loosening due to displacement or swelling of the gripping part occurred. In addition, the use of a strong adhesive causes problems such as the appearance of dents because the resin dissolves in the organic solvent contained in the component.
Further, in the case of heat welding, since a heat seal or the like is wound around the outer surface, there is a problem that a welding mark remains on the outer surface.
Further, in the case of ultrasonic welding, since vibration is absorbed by the elastic resin, it is difficult for the resins to be dissolved, and a sufficient welding strength cannot be obtained. Here, if the output of the ultrasonic wave is increased, heat is transmitted to parts other than the bonding surface, resulting in a defective appearance and damage to the hard resin material to be bonded. It was.

  Therefore, the present invention provides a shaft body formed by inserting and abutting one of two or more shaft cylinders into the other, and at least one of the shaft cylinders is made of an impermeable resin that is not transmissive to laser light. The material, and at least one of the shaft cylinders in contact with it is made of a transparent resin that is transmissive to the laser light, and the contact portion between the shaft cylinders is welded and joined by laser light irradiation. The second gist is that an elastic resin is used as at least one of the resins. Further, a third gist is that the shaft cylinder using the elastic resin is a gripping portion, and a fourth gist is that the shaft body is used for a writing instrument.

  The shaft body may be formed by inserting one of two or more shaft cylinders into the other and contacting. At least one of the shaft cylinders is made of a non-transparent resin that is not transmissive to laser light, and at least one of the shaft cylinders that contacts the shaft cylinder is made of a transmissive resin that is transmissive to laser light. To do. Other shaft cylinders are not particularly limited as long as they can be used as a shaft body such as resin, wood, and stone. These materials may be one kind or a mixture of two or more kinds.

  In the laser welding method, the laser light transmitted through the transparent resin material reaches the contact surface of the non-transparent resin material and is absorbed, and the laser light absorbed on the contact surface is accumulated as energy. As a result, the contact surface of the non-permeable resin material is heated and melted, and the contact surface of the transparent resin material is heated and melted by heat transfer from the contact surface of the non-permeable resin material. In this state, if the contact surfaces of the permeable resin material and the non-permeable resin material are pressure-bonded to each other, they can be joined together. In the joint portion thus obtained, the joining surfaces are melted and joined, and between the joining surfaces, both resins constituting both molded members are melted and are intertwined with each other. It has a strong bonding state and a high pressure strength by constituting a strong bonding state. For this reason, the contact portions of the shaft tubes need to be in close contact with each other when they are irradiated with laser. As means for close contact, there are methods such as applying pressure from the outside, screwing the shaft cylinders together, press-fitting, fitting by partial unevenness, and press-contacting one of the shaft cylinders by the elasticity using an elastic resin. However, there is no particular limitation as long as the abutting portions of the shaft cylinders that irradiate the laser are in pressure contact with each other. Since melting occurs only at the bonding interface (bonding surface), the surface is not violated, and no appearance problem occurs.

  The type of resin and / or elastic tree used for the transparent resin material is not particularly limited as long as it can transmit laser light as a heating source at a predetermined transmittance or higher. As the resin, polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), polyethylene resin (PE), polypropylene resin (PP), polystyrene resin (PS), acrylonitrile styrene resin (AS), acrylonitrile styrene butadiene resin (ABS), Methacrylic resin (PMMA), polyacetal resin (POM), polyamide resin (PA) such as nylon 6 resin (PA6) and nylon 66 resin (PA66), polycarbonate resin (PC), polyethylene terephthalate resin (PET), polybutylene terephthalate (PBT), ethylene tetrafluoride resin (PTFE), elastic resins include acrylic resin, silicone resin, fluorine resin, vinyl chloride, urethane resin, polyurethane resin, polyethylene resin, elastomer gel, Reethylene gel, urethane rubber, ethylene acrylic rubber, epichlorohydrin rubber, acrylic rubber, ethylene propylene rubber, chloroprene rubber, natural rubber, isoprene rubber, chlorinated polyethylene, nitrile rubber, styrene elastomer, olefin elastomer, ester elastomer, urethane Although an elastomer etc. are mentioned, if a shape can be maintained, it will not specifically limit. These resins and / or elastic resins may be one kind or a mixture of two or more kinds.

  The hardness of the elastic resin may be appropriately selected within a hardness range of 0 to 90 degrees for Shore A or 0 to 90 degrees for Asker C, and is not particularly limited. However, an elastic resin of 60 degrees or less on Shore A and 80 degrees or more on Asker C becomes hard and less sticky or swells on the surface. Therefore, it is an elastic resin of 60 degrees or less on Shore A and 80 degrees or less on Asker C. It is desirable.

  The type of resin and / or elastic resin used for the non-transparent resin material is not particularly limited as long as it can absorb laser light as a heating source without transmitting it. As the resin, polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), polyethylene resin (PE), polypropylene resin (PP), polystyrene resin (PS), acrylonitrile styrene resin (AS), acrylonitrile styrene butadiene resin (ABS), Methacrylic resin (PMMA), polyacetal resin (POM), polyamide resin (PA) such as nylon 6 resin (PA6) and nylon 66 resin (PA66), polycarbonate resin (PC), polyethylene terephthalate resin (PET), polybutylene terephthalate (PBT), ethylene tetrafluoride resin (PTFE), elastic resins include acrylic resin, silicone resin, fluorine resin, vinyl chloride, urethane resin, polyurethane resin, polyethylene resin, elastomer gel, Reethylene gel, urethane rubber, ethylene acrylic rubber, epichlorohydrin rubber, acrylic rubber, ethylene propylene rubber, chloroprene rubber, natural rubber, isoprene rubber, chlorinated polyethylene, nitrile rubber, styrene elastomer, olefin elastomer, ester elastomer, urethane Examples thereof include elastomers, and examples thereof include those in which a predetermined colorant such as carbon black, dye, pigment, or the like, which has sufficient absorbability for laser light, is mixed in a resin and / or elastic resin. In addition, an organic coloring material may be used as long as it exhibits sufficient absorbability with respect to laser light. Examples of such a coloring material include copper phthalodianine pigments.

  The combination of the resin used for the permeable resin material and the resin used for the non-permeable resin material is a combination of those compatible with each other. Resins such as combinations of nylon 6 and nylon 66, combinations of PET and PC, combinations of PC and PBT, and combinations of styrene elastomer and polypropylene resin (PP) in addition to combinations of resins of the same type And a combination of elastic resins, and a combination of elastic resins such as a combination of an olefin elastomer and urethane rubber, but any combination of compatible resins may be used.

The type of laser light used as a heating source is such that the transmittance in the transparent resin material is a predetermined value or more in relation to the absorption spectrum or plate thickness (transmission length) of the transparent resin material that transmits the laser light. Those having such wavelengths are appropriately selected. For example, a YAG: Nd ³⁺ laser (laser light wavelength: 1060 nm) or a semiconductor laser (laser light wavelength: 500 to 1000 nm) can be used. Irradiation conditions such as laser output, irradiation density and processing speed (moving speed) can be set as appropriate according to the type of resin, the absorption capacity of the permeable resin material, and the like. If the output of the laser beam is low, it becomes difficult to melt the joint surfaces of the resin materials, and if the output is high, the resin material evaporates or changes in quality and the strength is lowered.

  The fine solid 4 is disposed between the shaft body and the grip portion and / or in a space provided in the grip portion. Specific examples of the fine solid 4 include hard balls such as stainless steel, white and white, zirconia and ruby balls, ores such as diamond, ruby, sapphire, agate and quartz, rocks such as granite and marble, polyethylene, polyethylene terephthalate , Vinyl chloride, ABS, AS, PMMA, polypropylene, polycarbonate and other resins and their foams, acrylic resin, silicone resin, fluororesin, urethane resin, polyurethane resin, dimethyl silicone, methyl vinyl silicone, methyl phenyl vinyl silicone , Methyl fluoroalkyl silicone (fluorosilicone), fluoro-dimethyl copolymer silicone, urethane rubber, ethylene acrylic rubber, epichlorohydrin rubber, acrylic rubber, ethylene propylene rubber, chloroprene rubber, natural rubber , Isoprene rubber, chlorinated polyethylene, nitrile rubber, styrene elastomer, olefin elastomer, ester elastomer, urethane elastomer and other elastic resins, nylon, silk, cotton and other fibers, glass, etc. There is no particular limitation as long as it can be formed. These fine solids may be one kind or a mixture of two or more kinds.

  As the shape of the fine solid 4, various shapes of solid such as particles, fibers, and irregular shapes can be used. When a fine solid having a shape close to a true sphere, such as a hard sphere, is arranged, the deformation is fast when gripped, and the shape is restored quickly when released. When an irregularly shaped fine solid obtained by pulverizing rocks or glass is arranged, the gripping is slow, but there is a feeling of gripping, and the shape is remembered to some extent when released. The size of the fine solid varies depending on the size of the space, but is not particularly limited as long as it is smaller than the minimum width of the space. Further, the size of these fine solids may be one kind or a mixture of two or more kinds.

  In addition to the fine solid 4 in the space provided between the shaft body and the grip part and / or inside the grip part, an elastic resin or gel-like substance is used to assist the fluidity and shape retention of the fine solid. Auxiliary material 5 such as or a viscous material may be provided. Examples of viscous materials include silicone oils such as KF96 (manufactured by Shin-Etsu Chemical Co., Ltd.), silicone oil compounds such as tsk5370 (manufactured by Ge Toshiba Silicone), and petroleum-based oils such as Retinax Grease CL (manufactured by Showa Shell Sekiyu KK). Grease. As gel-like substances, silicone gels such as KE-1052, sifel 827 (manufactured by Shin-Etsu Chemical Co., Ltd.), alpha gel (manufactured by Geltech Co., Ltd.), SilGel612 (manufactured by Asahi Kasei Wacker Silicone Co., Ltd.), human skin gel ( Urethane gels such as those manufactured by Exeal Corporation are available.

  According to the present invention, in a shaft body formed by inserting and abutting one of two or more shaft cylinders into the other, at least one of the shaft cylinders is made of a non-transparent resin that is not transparent to laser light. In addition, at least one of the shaft cylinders that abut on it is made of a transparent resin that is transmissive to laser light, and the abutting portions of the shaft cylinders are welded and bonded together by laser light irradiation, thereby providing strong bonding Is realized. Even in the case of an elastic resin that has conventionally required the use of a primer and difficult to join firmly, both resins melt and enter each other to form an entangled state. And withstand pressure strength. In particular, the elastic resin often used as a gripping part has a problem of loosening due to swelling due to sweat. However, since both resins are melted to realize a strong welding, the problem is solved. In addition, since a sealed structure can be created by welding, the enclosure does not leak even if a fine solid and / or viscous material is placed in the space provided between the impermeable resin and / or the permeable resin. Is possible.

  In the present invention, a contact portion between a shaft tube formed of a non-transparent resin that is not transmissive to laser light and a shaft tube formed of a transmissive resin that is transmissive to laser light is used for the laser light. The main feature is welding by irradiation. We have made it possible to weld elastic resin, which has not been able to obtain strength and durability that can withstand use. Furthermore, a shaft body with an unprecedented tactile sensation has been realized by creatively inventing a sealed structure using strong welding.

Example 1
FIG. 1 is a component diagram of Example 1 in which the present invention is used for a shaft of a writing instrument. 2 is a cross-sectional view taken along the line AA ′ of FIG. Reference numeral 1 is a shaft cylinder 1, reference numeral 2 is a shaft cylinder 2, and reference numeral 3 is a welded portion.

  Carbon black as a laser-absorbing material is added to the shaft cylinder 1 injection molded using an elastomer (actimer AE-2040S, manufactured by Riken Technos Co., Ltd., Shore A hardness: 40 °) that is transmissive to laser light. A shaft cylinder 2 injection-molded using 5% by weight of polyethylene was inserted. Both ends of the shaft tube 2 are fixed and attached to a device that rotates in the radial direction. While rotating, the laser beam is irradiated around the welded portion 3 with a semiconductor laser device (wavelength 940 nm, output 40 W). The cylinder 2 was welded around the entire circumference of the welded part 3. The shaft tube 1 and the shaft tube 2 were not completely melted and detached, and no loosening occurred even when swollen with sweat or the like.

Example 2
FIG. 3 is a component diagram of Example 2 in which the present invention is used for a writing instrument shaft. 4 is a cross-sectional view taken along line aA ′ of FIG. Reference numeral 1 is a shaft cylinder 1, reference numeral 2 is a shaft cylinder 2, reference numeral 3 is a welded portion, reference numeral 4 is a fine solid, and reference numeral 5 is an auxiliary material. There is a space between the shaft tube 1 and the shaft tube 2, and the space 7 is sealed by welding the two contact portions of the shaft tube 1 and the shaft tube 2 all around to form the welded portion 3. 7 is filled with a fine solid 4 and an auxiliary material 5.

  A laser-absorbing material (LAW-1800, Orient Chemical Industry Co., Ltd.) is injected into the shaft cylinder 1 which is injection-molded using an elastomer (Lavalon MJ5302C, manufactured by Mitsubishi Chemical Corporation, Shore A hardness: 50 degrees). A shaft cylinder 2 injection-molded using polypropylene mixed with (made by Co., Ltd.) was inserted. Glass beads (Unibeads UB-1921LN, manufactured by Union Co., Ltd.) are arranged as a fine solid 4 in the space formed between the shaft tube 1 and the shaft tube 2, and silicone gel (KE-1052, Shin-Etsu Chemical Co., Ltd.) is placed in the gap. Product). Both ends of the shaft tube 2 are fixed, attached to a device rotating in the radial direction, and irradiated with laser light with a semiconductor laser device (wavelength 940 nm, output 40 W) while rotating, the shaft tube 1 and the shaft tube 2 are welded at two locations. . The shaft tube 1 and the shaft tube 2 were not completely melted and detached, and no loosening occurred even when swollen with sweat or the like. Further, since glass beads and silicone gel arranged in the space are sealed by welding, they do not leak to the outside. The glass beads change their position appropriately according to the pressure when grasped, and the movement is made softer by the silicone gel. For this reason, the grasping part 2 is deformed into the shape of a grasped finger and exhibits effects such as ease of holding and difficulty in sliding. The inner glass beads themselves are hard and elastic due to the silicone gel, so that they do not deform too much when grasped firmly, and a good feeling with a waist is obtained.

Example 3
FIG. 5 is a component diagram of Example 3 in which the present invention is used for a shaft of a writing instrument. 6 is a cross-sectional view taken along line AA ′ of FIG. Reference numeral 1 is a shaft cylinder 1, reference numeral 2 is a shaft cylinder 2, reference numeral 3 is a welded portion, reference numeral 4 is a fine solid, reference numeral 5 is an auxiliary material, reference numeral 6 is a shaft cylinder 3, and reference numeral. 7 is a space. The shaft tube 1 is formed in a bag shape, and a sealed space 7 is formed by welding the contact portion with the shaft tube 2 serving as a lid all around to form a weld portion 3. A fine solid 4 and an auxiliary material 5 are enclosed.

  A bag-shaped shaft tube 1 is formed by using an elastomer (Lavalon MJ6302C, manufactured by Mitsubishi Chemical Co., Ltd., Shore A hardness: 60 degrees) that is transparent to laser light on a shaft tube 3 that is injection-molded using polypropylene. Color molded. Glass beads (Unibeads UB-1921LN, manufactured by Union Co., Ltd.) are arranged as fine solids 4 in the space formed in the shaft tube 1, and silicone gel (KE-1052, manufactured by Shin-Etsu Chemical Co., Ltd.) is placed in the gap. Filled. A shaft cylinder 2 injection-molded using polypropylene mixed with a laser absorbing material (LAW-1800, manufactured by Orient Chemical Industry Co., Ltd.) was inserted between the shaft cylinder 1 and the shaft cylinder 3. The shaft tube 2 and the shaft tube 3 are fitted by unevenness. Both ends of the shaft tube 3 were fixed, attached to a device rotating in the radial direction, and irradiated with laser light with a semiconductor laser device (wavelength 940 nm, output 40 W) while rotating, the shaft tube 1 and the shaft tube 2 were welded. The shaft tube 1 and the shaft tube 2 were not completely melted and detached, and no loosening occurred even when swollen with sweat or the like. Further, since glass beads and silicone gel arranged in the space are sealed by welding, they do not leak to the outside. The glass beads change their position appropriately according to the pressure when grasped, and the movement is made softer by the silicone gel. For this reason, the grasping part 2 is deformed into the shape of a grasped finger and exhibits effects such as ease of holding and difficulty in sliding. The inner glass beads themselves are hard and elastic due to the silicone gel, so that they do not deform too much when grasped firmly, and a good feeling with a waist is obtained.

Example 4
FIG. 8 is a component diagram of Example 4 in which the present invention is used for a writing instrument shaft. 9 is a cross-sectional view taken along the line AA ′ of FIG. Reference numeral 1 is a shaft cylinder 1, reference numeral 2 is a shaft cylinder 2, reference numeral 3 is a welded portion, reference numeral 4 is a fine solid, reference numeral 5 is an auxiliary material, reference numeral 6 is a shaft cylinder 3, and reference numeral. Reference numeral 7 denotes a space, and reference numeral 8 denotes a through hole provided in the shaft cylinder 2. The shaft cylinder 1 is formed into a bag shape, and a fine solid 4 and an auxiliary material are formed in a space 7 formed by welding the contact portion with the shaft cylinder 2 serving as a lid all around to form a weld portion 3. 5 is arranged.

  A bag-shaped shaft tube 1 is formed by using an elastomer (Lavalon MJ6302C, manufactured by Mitsubishi Chemical Co., Ltd., Shore A hardness: 60 degrees) that is transparent to laser light on a shaft tube 3 that is injection-molded using polypropylene. Color molded. Glass beads (Unibeads UB-1921LN, manufactured by Union Co., Ltd.) were arranged as fine solids 4 in the space 7 formed in the shaft tube 1. A shaft cylinder 2 injection-molded using polypropylene mixed with a laser absorbing material (LAW-1800, manufactured by Orient Chemical Industry Co., Ltd.) was inserted between the shaft cylinder 1 and the shaft cylinder 3. The shaft tube 2 and the shaft tube 3 are fitted by unevenness. Both ends of the shaft tube 3 were fixed, attached to a device rotating in the radial direction, and irradiated with laser light with a semiconductor laser device (wavelength 940 nm, output 40 W) while rotating, the shaft tube 1 and the shaft tube 2 were welded. Silicone gel (SilGel612 (manufactured by Asahi Kasei Wacker Silicone Co., Ltd.)) was filled from the outside through the through-hole 8 in the space 7 in which the fine solid 4 was disposed. No loosening occurred even when swollen with sweat, etc. Further, the glass beads and silicone gel arranged in the space 7 leaked to the outside because the shaft tube 1 and the shaft tube 2 are welded. Since the through-hole 8 is smaller than the glass bead, the glass bead in the space does not come out to the outside.The silicone gel is deformed by pressure, but the deformation amount is limited, and the pressure is applied. However, the glass beads that have moved due to pressure do not block the through-holes 8 because they move more easily inside the space 7 than the leaks from the narrow through-holes 8. Therefore, the silicone gel is stopped before it leaks to the outside, and the glass beads change their position appropriately according to the pressure when grasped, and the movement is softened by the silicone gel. It is deformed into the shape of a finger and is easy to hold and difficult to slide.The inner glass beads themselves are hard and elastic with silicone gel, so they do not deform too much when gripped firmly and have a waist A good feel is obtained.

Comparative Example 1
The shaft cylinder 1 of Example 1 was fixed using an adhesive. However, the elastomer of the shaft cylinder 1 is an elastic resin containing an oil component in the material and is a difficult-to-adhere substance. When swollen with sweat or the like, the adhered portion is peeled off and loosened.

Comparative Example 2
The welding in Example 2 was performed using a heat welding machine. Thermal welding is a method of transferring thermal energy through a material and welding the interface. However, since the heat generation source is brought into contact with the shaft tube 1 to transmit heat, the surface of the shaft tube 1 is melted by heat until it is welded, and the appearance is soiled.

Comparative Example 3
The welding of Example 3 was performed using an ultrasonic welding machine. Ultrasonic welding is a method in which vibration is transmitted through a material and the interface is welded. However, since the elastomer of the shaft tube 1 is an elastic material and the vibration is attenuated, the welding is incomplete, and it is detached during use.

  The present invention relates to a shaft body formed by inserting and abutting one of two or more shaft cylinders into the other. Examples of shafts include writing instruments such as mechanical pencils, ballpoint pens, correction pens, tools such as cutters and engraving swords, drivers, input pens used in PDAs (personal digital assistance) and electronic notebooks, bicycle handles, etc. Wide range.

It is component drawing of Example 1 which used this invention for the shaft of a writing instrument. It is the a-A 'line sectional view of Drawing 1. It is component drawing of Example 2 which used this invention for the shaft of a writing instrument. FIG. 4 is a sectional view taken along line a-A ′ of FIG. 3. It is component drawing of Example 3 which used this invention for the shaft of a writing instrument. FIG. 6 is a sectional view taken along line a-A ′ of FIG. 5. It is a principal part enlarged view of FIG. It is component drawing of Example 4 which used this invention for the shaft of a writing instrument. FIG. 9 is a sectional view taken along line a-A ′ of FIG. 8. It is a principal part enlarged view of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Shaft cylinder 2 Shaft cylinder 3 Welding part 4 Fine solid 5 Auxiliary material 6 Shaft cylinder 7 Space 8 Through-hole

Claims (7)

In a shaft body formed by inserting and abutting one of the two or more shaft cylinders into the other, at least one of the shaft cylinders is made of a non-transparent resin that is not transmissive to laser light and abuts on the material A shaft body characterized in that at least one of the shaft cylinders is made of a transparent resin that is transmissive to laser light, and abutting portions of the shaft cylinders are welded and joined by laser light irradiation. 2. The shaft body according to claim 1, wherein an elastic resin is used for at least one of the resins. The shaft body according to claim 2, wherein the shaft cylinder using the elastic resin is a grip portion. By welding and joining the abutting portions of the shaft cylinders by laser light irradiation, a fine solid and / or elastic resin and / or a space provided between the shaft cylinders and / or in the space inside the shaft cylinder, and / or Or the viscous body was arranged, The shaft body in any one of Claims 1-3 characterized by the above-mentioned. The shaft according to any one of claims 1 to 4, wherein the fine solid disposed in the space is in the form of particles and / or fibers. The shaft according to any one of claims 1 to 6, wherein the viscous material arranged in the space is a gel material. A writing instrument using the shaft body according to claim 1.

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