JP5396832B2 - Shaft cylinder - Google Patents

Description

  The present invention relates to a shaft cylinder in which leather is wound around an outer peripheral surface of a cylindrical shaft.

The materials used for the writing instrument shaft are mainly divided into resin and metal. Many shafts made of resin are inexpensive for office use, and shafts made by injection molding using a thermoplastic resin are used as they are. Further, the metal shaft has a heavy feeling and is generally used with resin coating or decorative plating for the purpose of corrosion prevention and decoration. For this reason, the metal shaft is mainly used for a writing instrument which is said to be a high-quality product with a relatively high purchase price.
Also, in order to differentiate from other companies and to give a high-class feel, products that have cowhide, sheep leather, lizard leather, etc. wound around the shaft have been introduced to the market. In order to wrap around the writing instrument shaft neatly, both ends of the leather are slanted and bonded to prevent the joint part from rising, or pushed into the shaft to process the joint part. It was.
Therefore, in the prior art, the fiber part of the cut part of the leather is prevented from fraying by use by bonding the ends of the leather or pushing the leather protruding from the base part into the shaft. .

However, as for the shaft cylinder wound with leather, as in the prior art, the emphasis is placed on the processing of the leather seam, and the situation is that attention has not been paid to the leather parts at both ends of the shaft cylinder. .
Therefore, in the prior art, the leather protruding from both ends of the base portion of the shaft tube is cut off with a knife or the like along the end surface of the shaft tube, or the leather protruding from the base portion of the shaft tube is removed from the base portion. It was processed by wrapping leather inside. And the fiber part was still exposed to the end surface of the leather with the shaft cylinder cut off.
In addition, parts such as a tip member and a core are joined to both ends of the shaft cylinder wound with leather in order to provide a writing instrument function. The leather protruding from the base material portion of the shaft cylinder is sandwiched and joined by the tip member and the base material portion of the shaft cylinder, and the leather end face is fixed and the fibrous portion is prevented from fraying.
JP-A-2004-291380 JP 2001-233221 A

  To prevent the fiber part of the leather on the end face of the shaft tube from fraying, cover the end surface of the leather with the tip member, or fix the leather between the tip member and the shaft tube or between the core and the shaft tube. Can prevent fraying. However, in order to cover the leather on the end surface of the shaft tube, it is necessary to fix the tip member or core having an inner diameter larger than the outer diameter of the shaft tube to cover the leather on the end surface of the shaft tube wound with leather. There is. Therefore, if the clearance between the outer diameter of the shaft cylinder and the inner diameter of the tip member (core) is not appropriate, the leather surface portion will protrude outside the tip member, or there will be a gap between the leather surface portion and the inner diameter portion of the tip member. There was a problem that it would be unfavorable in terms of appearance as soon as it was made.

On the other hand, when fixing leather with a leather-wound shaft tube and a tip member, the leather protruding from the base portion of the shaft tube is folded inside the shaft tube, and the tip member or core is inserted through the folded leather. Or insert the space inside the tip member to store the portion of the leather that protrudes from the base material portion of the shaft tube. There is a way to fix.
Bending the leather protruding from the base part of the shaft tube inside the shaft tube, and inserting and fixing the tip member and the core inside the shaft tube through the folded leather, if the leather is thick The thicker the portion is, the more easily the wrinkled portion is wrinkled.
In addition, in order to sandwich and fix the leather protruding from the base portion of the shaft tube between the shaft tube and the tip member, while pulling the leather protruding from the base portion of the shaft tube so as not to sag or wrinkle, the tip member Must be fixed to the shaft cylinder, and all of the protruding part of the leather must be stored cleanly inside the tip member. There were several simultaneous work processes to fix the assembly, and the assembly was also complicated. Therefore, the appearance defect on assembly increased.
Therefore, when assembling a writing instrument, it was not possible to provide a leather-wound cylinder that can be manufactured stably without deteriorating appearance quality.

As an improvement measure, the end cylinder of the shaft tube is thermoformed, and further, the end surface of the leather thermoformed by the tip member is covered, so that there is no problem in appearance quality at the joint portion of the shaft tube and the tip member. The present invention has been found out and can be completed.
That is, a barrel adhered coating leather with an adhesive rubber on the outer peripheral surface of the cylindrical axis, R-shaped or tapered by a metal trowel that is thermally leather outer peripheral side of the at least one end of the barrel Jo to thermoformed, the ends of the leather obtained by the heat molding, and summarized in that coated by a member attached to an end of the barrel.

  Since the leather on the end face of the shaft cylinder wrapped with leather is thermoformed and the part joined to the tip member has a uniform outer diameter, a high-quality writing instrument that uses the leather-wound cylinder is industrially stable. Can now be manufactured.

  In the present invention, since the end face of the leather of the shaft cylinder around which the leather is wound is thermoformed, the leather that can stably manufacture the writing instrument without deterioration in the appearance quality at the joint portion between the tip member and the core and the shaft cylinder is wound. A shaft cylinder was realized. In addition, by covering the end surface of the thermoformed leather with a tip member or core, an extra gap can be created at the joint between the leather-wound shaft tube and the part, or the fibrous portion of the leather end surface can be It was possible to provide a shaft cylinder wrapped with leather that does not protrude from the core and has no deterioration in appearance quality.

  The present invention will be described in detail with reference to the drawings. This is an example in which the present invention is applied to a shaft cylinder of a writing instrument such as a ballpoint pen or a mechanical pencil. Reference numeral 1 denotes a base material of the present invention, which is made of copper or aluminum and an alloy thereof. The forming method of the substrate 1 is not particularly limited because conventional techniques such as cutting and press forming can be applied. In order to improve the affinity of the adhesive for attaching the leather to the substrate, the surface of the substrate may be etched with a chromic acid solution or black chrome plating may be formed.

Reference numeral 2 is leather. It is a general leather that is sold as a material used in bags, gloves, and clothing. The type of leather is not particularly limited as long as it is a commercially available leather such as cow, sheep, lizard, crocodile, and ostrich. Leather is cut in advance according to the size of the substrate to be wrapped, and the thickness is adjusted while scraping the fibrous part on the back side, and carefully wrapped around the substrate using an adhesive so as not to be wrinkled. It is done. Finally, in order to prevent dirt and give a glossy feeling, there is no problem even if the leather surface (silver surface) is subjected to clear coating with lacquer.
The thickness of the leather is preferably 0.1 mm to 1 mm, but is not particularly limited. If the leather thickness is less than 0.1 mm, the strength of the leather is small and it is easy to tear, and leather with unevenness such as lizard leather cannot be used. In addition, if it exceeds 1 mm, it becomes technically difficult to treat the joint of the leather, and there are various problems such as poor workability when attaching leather, and the diameter of the shaft tube becomes thick. Occur. Further, since the thickness of the leather is adjusted by rinsing the fibrous portion (mesh-like layer) on the back side, it is generally not uniform when viewed as a whole.

Reference numeral 3 denotes a tip member. The tip member 3 is a part that is fixed to the tip end side of the shaft tube 1 in the writing instrument and causes the refill (ball pen body) 5 for writing to appear and disappear. The material of the tip member 3 is a metal or a resin, but brass, aluminum, or ABS resin is preferable particularly when surface treatment such as plating is performed. The tip member 3 is fixed in front of a shaft tube (base material) wound with leather by screwing, press fitting, or adhesion. The tip member 3 in FIG. 2 is an example that is fixed to a base material with a screw.
Further, a collar portion 3a is formed at the upper end portion of the tip member 3, and the front end portion of the leather 2 wound around the shaft cylinder is covered by the collar portion 3a.

  Reference numeral 4 denotes a core. The core 4 is a component that connects the front portion (base material 1) and the rear portion (rear shaft 6) in the writing instrument. Resin and metal are used as the material of the core 4, and metal is preferred when strength is required and surface treatment is performed. The core 4 is fixed behind the shaft cylinder (base material 1) wound with leather by screwing, press-fitting, or adhesion. The core 4 in this example is fixed to the base material 1 by press-fitting and adhesion.

Next, the thermoforming of the leather on the end face of the shaft cylinder 7 around which the leather 2 is wound will be described in detail. FIG. 1 is a longitudinal sectional view of a shaft cylinder 7 wound with leather 2 that has been thermoformed. The leather 2 is animal skin and a mass of protein. Therefore, it melts by heat. The end face is thermoformed using this property. It was confirmed that the end surface of the leather that was melted by heat and then cooled and hardened also melted the fibrous portion that caused fraying. The thermoforming methods include a method of instantaneously heating with a flame, a method of bringing a baked iron heated with an electric heater or the like into contact with the leather 2, a shaft cylinder 7 wrapped around the leather 2 being rotated at high speed and brought into contact with a metal, etc. Although the method of melting by the method can be used, it is not particularly limited.
The melting temperature is not particularly limited because it varies depending on the history of leather 2, such as the type and individual differences of leather 2, and the tanning state. However, if the temperature is too low, it does not melt, and if the temperature is too high, there is a risk that the leather 2 will be burnt or burned and the leather 2 will be altered.
The shape of the molding is preferably a shape as shown in FIGS. 1 or 3 (a) and (b), but is not particularly limited. (A) of FIG. 3 is an example which thermoformed the end surface of the leather cut | disconnected at right angle by the cross-sectional shape as it is. Specifically, only the end surface of the leather 2 in contact with the thermal iron is melted by pressing the end surface of the shaft cylinder 7 vertically against the thermal iron having a horizontal surface. The shape of (a) of FIG. 3 is effective when covering the end surface of the leather 2 thermoformed by the side surface of the collar portion 4a of the core 4.
3B, the end surface of the leather 2 is rounded, and when the tip member 3 covers the end surface of the leather 2, the end surface of the shaft cylinder does not get caught in the collar portion 3a of the top end portion of the tip member 3. It is thermoformed so as to enter.

Example 1
A cylindrical press-molded metal shaft (base material 1) made of an aluminum alloy was used. A ring-marked lizard leather 2 having a thickness of about 0.25 mm was adhered and pasted to the base material 1 using a commercially available rubber adhesive. After that, the leather 2 protruding from both ends of the base portion of the shaft tube was cut along the shaft tube end surface with a knife, and the shaft tube 7 around which the leather 2 was wound was created. Next, in order to perform thermoforming, a metal trowel having a tapered shape on the inner side surface in which a conical or frustoconical depression was formed on the end surface of the cylinder was used. The metal iron was heated to 230 ° C., and the shaft cylinder was pressed against the iron for 5 seconds so that the center line of the iron coincided with the center line of the shaft cylinder, and then gradually cooled to room temperature. As a result, a shaft cylinder 7 having a longitudinal sectional shape as shown in the sectional view of FIG. 1 was obtained. The thickness of the end face of the heat-formed leather 2 in the part contacting the tip member 3 was 0.2 mm.

Next, the shaft cylinder 7 wound with the leather 2 subjected to the thermoforming treatment and the tip member 3 are screwed and bonded. The tip member 3 has a shape having a flange 3a at the upper end so as to cover the leather of the end face of the shaft tube. The shaft cylinder 7 wound with the tip member 3 and the leather 2 is designed to be screwed. The clearance for covering the end surface of the shaft cylinder wound with the leather 2 is 0.25 mm from the outer shape of the base material 1 to the inner diameter of the flange portion 3 a of the tip member 3. A commercially available epoxy adhesive (two-component curable type) was applied to the threaded portion 1a of the substrate 1, and the tip member 3 was screwed and joined so as to cover the thermoformed portion with the flange portion 3a.
The joint of the shaft cylinder 7 wound with the leather 2 and the tip member 3 was cleanly processed, and a high-quality writing instrument shaft cylinder in which the soft texture of the leather was felt was obtained.

(Example 2)
The metal shaft (base material 1) by the cylindrical cutting which consists of copper alloys was used. A cowhide leather 2 having a thickness of 0.5 mm was adhered and pasted to the base material 1 using a commercially available rubber adhesive. After that, the leather 2 protruding from both ends of the base 1 of the shaft cylinder 7 was cut along the end surface of the shaft cylinder 7 with a knife, and the shaft cylinder 7 around which the leather 2 was wound was created. Next, the shaft cylinder 7 was pressed vertically for 10 seconds on a baking iron having a flat surface heated to 200 ° C., and only the end surface contacting the iron was subjected to thermoforming. A shaft cylinder 7 having a longitudinal sectional shape as shown in FIG. 3A in which only the cut surface of the leather 2 was thermoformed was obtained.

Next, the shaft cylinder 7 and the core 4 wound with the leather 2 subjected to the thermoforming treatment are press-fitted and bonded. The core 4 serves as a stopper so as to have a prescribed press-fitting depth when press-fitted into the shaft tube, and covers the end face of the thermoformed leather so that the end face of the leather 2 does not directly contact the finger. A flange portion 4a is formed in the intermediate portion. The outer diameter of the collar part 4a is 0.2 mm larger than the outer diameter of the shaft cylinder 7 around which the leather 2 is wound.
A commercially available epoxy adhesive (two-component curing type) was applied to the inner diameter portion of the substrate 1, and the core 4 was press-fitted and fixed. The thermoformed end face of the leather 2 is not covered as in the first embodiment, but is in surface contact with the side face of the flange 4a of the core 4 and is not exposed on the surface.
A high-quality writing instrument shaft was obtained in which the joint between the shaft cylinder 7 and the core 4 wound with the leather 2 was processed neatly and the soft texture of the leather was felt.

(Comparative Example 1)
A cylindrical press-molded metal shaft (base material 1) made of a copper alloy was used. A ring-marked lizard leather 2 having a thickness of 0.25 mm was adhered and pasted to the base material 1 using a commercially available rubber adhesive. After that, the leather 2 protruding from both ends of the base 1 of the shaft cylinder 7 was cut along the end surface of the shaft cylinder 7 with a knife, and the shaft cylinder 7 around which the leather 2 was wound was created. The thickness of the end surface of the leather 2 at the portion in contact with the tip member 3 was 0.3 mm.

Next, the shaft cylinder 7 wound with the leather 2 and the tip member 3 were screwed and bonded together. The tip member 3 has a shape having a flange portion 3a at the upper end portion so as to cover the leather of the end surface of the shaft tube. The shaft cylinder 7 wound with the tip member 3 and the leather 2 is designed to be screwed. The clearance for covering the end surface of the shaft cylinder wound with the leather 2 is 0.25 mm from the outer shape of the base material 1 to the inner diameter of the flange portion 3 a of the tip member 3. A commercially available epoxy adhesive (two-component curable type) was applied to the threaded portion 1a of the substrate 1, and the tip member 3 was screwed and joined so as to cover the thermoformed portion with the flange portion 3a.
Since the thickness of the end face of the leather 2 at the portion in contact with the tip member 3 was 0.3 mm, the end face of the leather 2 protruded beyond the collar portion 3a portion of the tip member 3, and the appearance of the leather protruded. The part was caught on the finger and the usability was bad.

  Since such a form in which both ends of the leather-wound shaft tube are thermoformed is adopted, the present invention can be applied not only to writing instruments but also to cosmetic tools and gripping parts.

It is the longitudinal cross-sectional view which expanded the end surface of the axial cylinder of this invention. It is a longitudinal cross-sectional view of the writing instrument of the present invention. (A) It is the longitudinal cross-sectional view of the axial cylinder which showed the example of the melt molding of this invention. (B) It is the longitudinal cross-sectional view of the axial cylinder which showed the example of the melt molding of this invention.

DESCRIPTION OF SYMBOLS 1 Base material 1a Thread part 2 Leather 3 Tip member 3a collar part 4 Core 4a collar part 5 Refill (ball-point pen body)
6 Rear shaft 7 Shaft cylinder

Claims (1)

A barrel adhered coating leather with an adhesive rubber on the outer peripheral surface of the cylindrical axis, the R-shaped or tapered by a metal trowel that is thermally leather outer peripheral side of the at least one end of the barrel A shaft cylinder characterized by being thermoformed and covering the end of the thermoformed leather with a member attached to the end of the shaft cylinder.

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