JP2007253548A - Barrel of writing utensil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide the barrel of a writing utensil by a simple structure, in which a snout member does not easily come off due to the lessening of the clamping force of the snout member and a gripping member is arranged under its compressed state. <P>SOLUTION: In the barrel of the writing utensil, in which the threading between a front shaft and a rear shaft completes by advancing the stepped part of the front shaft into the rear shaft under the condition that the gripping member is arranged between the stepped part formed in the front shaft and the rear end surface of the snout member and, at the same time, the outer diameter of the stepped part of the front shaft and the inner diameter of the rear shaft, the gripping member is loosely fittingly arranged between the stepped part of the front shaft and the rear end surface of the snout member by making the length of the gripping member shorter than the distance between the stepped part of the front shaft and the rear end surface of the snout member. By forming the outer diameter of the gripping member larger than the outer diameter of the stepped part of the front shaft and the inner diameter of the rear shaft and by making the distance between the edge face of the snout member and the tip surface of the rear shaft shorter than the length of the gripping member, the pinching arrangement of the gripping member under its compressed state is realized between the tip surface of the rear shaft and the rear end surface of the snout member. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention constitutes a barrel body by screwing a front shaft and a rear shaft, and a tip member is attached to a tip portion of the front shaft, and a grip is provided between the rear end surface of the tip member and the front end surface of the rear shaft. The present invention relates to a shaft tube of a writing instrument which is formed by sandwiching a member in a compressed state.

  Conventionally, a shaft cylinder body is configured by screwing a front shaft and a rear shaft, and a grip member is disposed between a step portion of the front shaft and a rear end surface of a tip member screwed to a tip portion of the shaft tube. One writing instrument shaft is known.

  In such a structure of the shaft of the writing instrument, the grip member is sandwiched between the step portion of the front shaft and the rear end surface of the tip member screwed to the front end portion of the shaft tube, and is arranged in a compressed state. This is because the grip member may move back and forth and rotate during writing, or when the lip member is screwed, the rear end surface of the lip member and the front end surface of the grip member and / or the rear end surface of the grip and the front shaft This is to prevent a gap from being formed between the parts.

  However, in order to compress the grip member, the rear end surface of the tip member and the tip end surface of the grip member need to be screwed in surface contact, and therefore, when the tip member is screwed, compared to the case where the grip member is not compressed. As a result, it is difficult to screw the lip member, and due to insufficient tightening of the lip member, the lip member is easily detached and may be detached during movement or use.

  As means for solving such a problem, the applicant of the present application disclosed in Japanese Patent Application Laid-Open No. 2002-219896 “Shaft of writing instrument” by forming a recess in the front end surface of the grip member and the rear end surface of the grip member. However, when the tip member is small or the tip member is made of metal, there is a problem that even if the tip member is gripped, it is slippery and difficult to screw. .

By the way, the screw cylinder of the writing instrument in which the front shaft and the rear shaft are screwed together ends when the front shaft and the rear shaft come into contact with each other. Therefore, if an excessive force is applied during screwing, the front shaft and / or the rear shaft may be damaged. Therefore, it is necessary to adjust the force for screwing the front shaft and the rear shaft. Due to insufficient tightening of the front shaft and the rear shaft, the front shaft and the rear shaft may be easily detached.
"Japanese Patent Laid-Open No. 2002-21989"

  In view of these problems, the present invention provides a writing instrument shaft cylinder with a simple structure that reduces the clamping force of the lip member and prevents the lip member from being easily detached, and the grip member is disposed in a compressed state. It is in.

  The present invention comprises a shaft cylinder main body by screwing a front shaft and a rear shaft, a tip member is screwed to a front end portion of the front shaft, and a stepped portion formed on the front shaft and a rear end surface of the tip member A grip member is disposed between the front shaft and the outer diameter of the step portion of the front shaft is made smaller than the inner diameter of the rear shaft, and the step portion of the front shaft enters into the rear shaft and the front shaft and the rear shaft A writing tube formed by finishing screwing, wherein the distance between the step portion of the front shaft and the rear end surface of the tip member is smaller than the distance between the step portion of the front shaft and the rear end surface of the tip member. The grip member is disposed in a fitting shape, and the rear end outer diameter of the grip member is formed larger than the outer diameter of the step portion of the front shaft and the inner diameter of the rear shaft, and between the end surface of the tip member and the front end surface of the rear shaft The grip member is compressed between the front end surface of the rear shaft and the rear end surface of the mouthpiece member by making the distance of less than the length of the grip member. Characterized in that by holding the state are then arranged.

  Further, the front shaft and the rear shaft are detachably screwed.

  According to the present invention, it is possible to provide a writing instrument shaft cylinder with a simple structure in which the clamping force of the tip member is reduced and the tip member is not easily detached, and the grip member is disposed in a compressed state.

  Next, examples of the shaft cylinder of the writing instrument of the present invention will be described with reference to the drawings, but the present invention is not limited to the following examples.

Example 1
The shaft cylinder 1 of the writing instrument shown in FIG. 1 to FIG. 4 constitutes a shaft cylinder main body by detachably screwing the rear end male screw portion 2c of the front shaft 2 and the female screw portion 3c of the rear shaft 3, A female screw portion 5c of the tip member 5 formed by cutting brass on the tip male screw portion 2b is detachably screwed between the rear end surface 5b of the tip member 5 and the tip surface of the step portion 2a of the front shaft 2. A gripping member 4 previously formed from a thermoplastic elastomer is disposed to obtain a writing cylinder 1.

  Further, the clip member 10 is provided on the rear shaft 3, and the protrusion 12 is provided between the protrusion 12 extending toward the clip member 10 provided on the outer wall of the rear end portion of the rear shaft 3 and the inner wall surface of the clip member 10. A coil spring 13 is provided so as to cover the inner wall surface 10a at the tip of the clip member 10 and is always attached to the outer wall surface side of the rear shaft 3 by being elastic. Further, by pressing the rear end portion 10b of the clip member 10 toward the rear shaft 3, the connecting portion S between the both side walls 10c of the clip member 10 and the column 11 of the rear shaft 3 is used as a fulcrum, and the distal end portion of the clip member 10 is used. The inner wall surface 10a can be separated from the outer wall surface of the rear shaft 3.

  The shaft cylinder body composed of the front shaft 2 and the rear shaft 3 includes a knock body 6 disposed so as to protrude outward from the rear end of the rear shaft 3, and a receiver in the rear shaft 3 in front of the knock body 6. The rotary cam 7 is disposed by being biased in the direction of the rear shaft rear end 3a by a coil spring 8 disposed in contact with the member 14, and a cam groove (not shown) formed on the inner wall of the rear shaft. The rotary cam is provided with a retracting mechanism, and the shaft 1 of the writing pen of the knock type ball-point pen in which the rear end portion of the ball-point pen refill 8 having the ball-point pen tip 9 attached to the tip of the rotary cam 7 is press-fitted.

  In the shaft cylinder 1 of the writing instrument of the present invention, first, the grip member 4 is disposed on the front shaft 2 and the tip member 5 is screwed. At this time, the length L of the grip member 4 is smaller than the distance M between the rear end surface 5b of the front end member 5 and the front end surface of the step 2a of the front shaft 2 after the front shaft 2 and the front end member 5 are screwed (L By doing <M>, the grip member 4 is disposed in a loose fit between the front end surface of the step portion 2a of the front shaft 2 and the rear end surface 5b of the tip member 5. As a result, even if the tip member 5 is small and made of metal and is slippery, there is no resistance due to the grip member 4, so the tip member 5 can be easily and reliably screwed.

  Further, the grip member 4 is disposed in a loose fit between the front end surface of the step portion 2a of the front shaft 2 and the rear end surface 5b of the tip member 5, so that the front shaft can be moved rearward at the time of assembling or replacing the ballpoint pen refill. The grip member does not fall off even if it is removed from the shaft.

  Thereafter, the front shaft 2 on which the grip member 5 is loosely fitted is screwed to the rear shaft 3. At this time, the rear end outer diameter F of the grip member 5 is formed larger than the outer diameter G of the step portion 2a of the front shaft 2 (F> G), and the outer diameter G of the step portion 2a of the front shaft 2 is set to the rear. The inner diameter H of the front end portion of the shaft 3 is smaller (G <H), and between the rear end surface 5b of the tip member 5 and the front end surface 3b of the rear shaft 3 after the front shaft 2 and the rear shaft 3 are screwed. When the front shaft 2 and the rear shaft 3 are screwed together by making the distance N smaller than the length L of the grip member (N <L), the step portion 2a of the front shaft 2 enters the rear shaft 3, and the grip The front end surface 4a and the rear end surface 4b of the member 4 are in contact with the rear end surface 5b of the tip member 5 and the front end surface 3b of the rear shaft 3, and are compressed between the rear end surface 5b of the front end member 5 and the front end surface 3b of the rear shaft 3. It is arranged.

  By gripping the grip member 4 in a compressed state by screwing the front shaft 2 to the rear shaft 3, it is easier to grip than in the case of screwing the tip member 5 and clamping the grip member 4 in a compressed state. Since it is difficult to slide, it can be easily screwed and the assembly workability is improved.

  Further, the screwing of the front shaft 2 and the rear shaft 3 ends when the step portion 2a of the front shaft 2 and the inner wall step portion 3d of the rear shaft 3 come into contact with each other. Since the grip member 4 is compressed and clamped, a resistance force due to the compression of the grip member 4 is applied before the front shaft 2 and the rear shaft 3 are screwed together. 3 can be made difficult to break.

  Since the ballpoint pen refill 8 disposed in the shaft 1 of the writing instrument can be replaced by removing the front shaft 2 from the rear shaft 3, the ballpoint pen refill 8 can be replaced without removing the tip member 5. This is preferable because the replacement work becomes easier.

  In the embodiment of the present invention, the rear shaft is formed by one part for convenience, but it is not particularly limited, for example, it is formed by two parts of the middle cylinder and the outer cylinder. In the embodiments, the grip member is formed of a thermoplastic elastomer. However, the grip member of the present invention is elastically deformable natural rubber, silicone rubber, butyl rubber, fluorine rubber, vinyl chloride resin, butadiene rubber, urethane rubber. It may be appropriately selected from elastic bodies generally known as grip members such as polyethylene resin and other synthetic rubbers. Further, the tip member is not limited to metal, and may be appropriately selected from materials generally known as the tip member such as a resin material.

  It can be widely implemented as a writing cylinder, and it is difficult to easily remove the lip member due to insufficient tightening of the lip member, which is effective when commuting or traveling to school. Also, the ballpoint pen refill can be easily replaced by removing the front shaft and the rear shaft.

It is a longitudinal cross-sectional view which shows the axial cylinder of the writing instrument of this invention. It is a principal part expanded sectional view in FIG. It is the figure which abbreviate | omitted partially showing the assembly process of the tip member in FIG. 1, a front axis | shaft, and a rear axis | shaft. It is a figure which shows the state which screwed the tip member and the front shaft in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Writing cylinder 2 Front shaft 2a Step part 2b End male screw part 2c Rear end male screw part 3 Rear shaft 3a Rear end 3b Front end face 3c Female thread part 3d Inner wall step part 4 Grip member 4a Front end face 4b Rear end face 5 Tip member 5a Rear End surface 5b Female thread portion 6 Knock body 7 Rotating cam 8 Ballpoint pen refill 9 Ballpoint pen tip F Grip member rear end outer diameter G Stepped portion outer diameter H Rear shaft tip end inner diameter L Grip member length M Rear end surface of the tip member Between the step part of the front shaft and the length N between the rear end surface of the tip member and the front end surface of the rear shaft

Claims (2)

A shaft cylinder body is formed by screwing the front shaft and the rear shaft, a tip member is screwed to the front end portion of the front shaft, and a grip member is formed between the step portion formed on the front shaft and the rear end surface of the tip member. The outer diameter of the step portion of the front shaft is made smaller than the inner diameter of the rear shaft, and the step portion of the front shaft enters the rear shaft to screw the front shaft and the rear shaft. A finished writing instrument barrel, which is smaller than the distance between the step portion of the front shaft and the rear end surface of the tip member, and is freely fitted between the step portion of the front shaft and the rear end surface of the tip member. And the rear end outer diameter of the grip member is larger than the outer diameter of the step portion of the front shaft and the inner diameter of the rear shaft, and the distance between the end surface of the tip member and the front end surface of the rear shaft is By reducing the length of the grip member, the grip member is compressed between the front end surface of the rear shaft and the rear end surface of the tip member. Barrel of a writing instrument, characterized in that lifting to are then arranged. The writing instrument according to claim 1, wherein the front shaft and the rear shaft are detachably screwed together.

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