JP5300688B2 - Writing instrument shaft - Google Patents

Description

  The present invention relates to a shaft tube of a writing instrument in which a grip made of a soft material is detachably attached to a grip portion of a shaft tube body.

  Conventionally, in the grip of a writing instrument made of a soft material to be attached to the gripping portion of the shaft cylinder, an uneven portion formed in a concave or convex shape on the surface of the grip has been provided for the purpose of improving the anti-slip effect when gripped. The grips of writing instruments are well known.

  In the shaft of such a writing instrument, in the "shaft body" of JP-A-2005-41040, a plurality of annular protrusions are provided on the outer surface of the grip, and the width of the annular protrusion and / or the width of the annular groove is made different. An axial tube of a writing instrument that provides a good grip feeling of the grip is disclosed.

  Japanese Utility Model Laid-Open No. 7-15373, “Grip of Shaft”, describes a writing instrument in which a gap is formed between the grip and the shaft tube, and the grip is bent inward when gripped to obtain elasticity. A shaft cylinder is disclosed.

  Furthermore, Japanese Patent Application Laid-Open No. 2002-337495 “Grip member of writing instrument” discloses a grip in which an infinite number of fine line-shaped irregularities extending in the axial direction are uniformly provided on the inner wall of the grip.

Japanese Patent Laid-Open No. 2005-41040 Japanese Utility Model Publication No. 7-15373 JP 2002-337495 A

  By the way, as in Patent Document 1, in order to obtain a higher anti-slip effect and a good grip feeling in a grip formed with a convex portion, it is important that the grip is easily deformed when gripped. In order to easily deform the convex portion, it is conceivable to increase the height of the convex portion to increase the thickness, or to make the material used soft.

  However, in order to increase the wall thickness, it is necessary to increase the grip outer diameter. When the hardness is specified in order to make the material to be used soft, there is a problem that the usable soft material is limited.

  Further, as in Patent Documents 2 and 3, by forming a gap between the grip and the shaft tube, the grip can be bent inward when the grip is gripped, and the grip feeling can be improved. There is a problem that a gripping force that the grip is bent inward is required.

  An object of the present invention is to provide a writing tool shaft that is easily deformed even when the gripping force for gripping the grip is small and that is equipped with a grip with good assemblability.

  In order to achieve the above object, the present invention provides an axial tube of a writing instrument in which a grip made of a soft material is detachably attached to a grip portion of a shaft tube main body, and the grip is attached to an outer wall of a tip portion of the grip. A concave groove extending from the tip end surface of the grip along the axial direction of the axial tube body on the inner wall of the tip end portion of the grip. And a width of the groove is gradually reduced from the front end surface of the grip toward the rear end.

  Further, the thickness of the grip facing the bottom wall of the groove is larger than the width of the groove.

  Furthermore, the inner wall of the tip end portion of the grip is provided with an inner wall inclined portion whose inner diameter gradually decreases toward the tip end face side of the grip.

  Furthermore, a tip member is detachably screwed to the tip of the shaft tube main body, and the grip is compressed between the rear end surface of the tip member and the shaft tube body. And

  According to the configuration of the present invention, on the inner wall of the tip portion of the grip, a plurality of concave grooves extending from the front end surface of the grip along the axial center direction of the shaft cylinder body are formed, and the width of the concave groove is The grip wall is gradually reduced from the front end surface side toward the rear end direction, and an outer wall inclined portion having a gradually increasing diameter toward the front end direction of the grip is formed on the outer wall of the front end portion of the grip. is there. As a result, at the time of writing, the fingertip that grips the grip easily comes into contact with the outer wall inclined portion formed on the outer wall of the tip of the grip, and the outer wall inclined portion is thicker and further has a groove in the concave groove formed on the inner wall. Since the width is large, the approach from both the outer wall side and the inner wall side of the grip is easy to deform when gripped, and a good feel can be obtained.

  Further, at the time of writing, the fingertip that grips the grip comes into contact with the outer wall inclined portion formed on the outer wall of the tip of the grip, and writing can be performed by applying a force to the paper surface side. As a result, a force also acts on the axial center side of the shaft cylinder of the writing instrument from the inclined portion of the outer wall described above, and it is effective even if the gripping force of the grip is small due to the synergistic effect with the concave groove formed on the inner wall of the grip. The grip can be deformed.

  Further, by gradually reducing the width of the concave groove from the front end surface side to the rear end surface side of the grip, rotation of the grip can be suppressed and assemblability can be improved. By providing the groove on the inner wall of the grip, it is possible to reduce the contact area between the shaft cylinder body and the inner wall of the grip and improve the assemblability. In order to improve the assembling property, it is preferable to increase the groove width. However, in view of the effect of preventing rotation and the assembling property, and the ease of deformation when gripped as described above, the width of the groove is reduced. It is most effective to gradually reduce the grip from the front end surface side to the rear end surface side. In addition, by gradually reducing the width of the concave groove from the front end side of the grip toward the rear end, it is possible to increase the restoring force when rotated compared to the case of forming a groove of the same width. I think that.

  Further, by providing an inner wall inclined portion on the inner wall of the tip end portion of the grip such that the inner diameter gradually becomes smaller toward the tip end face side of the grip, the thickness of the outer wall inclined portion can be made thicker. In addition, since the depth of the groove can be increased, it is preferable because it can be easily deformed when gripped.

  Furthermore, the thickness of the grip facing the bottom wall of the concave groove is larger than the width of the concave groove, so that the amount of deformation does not increase more than necessary, and distortion, cracking, etc. due to repeated deformation The occurrence of defects can be suppressed.

  Furthermore, the tip member is detachably screwed to the tip of the shaft tube main body, and the grip is compressed and mounted between the rear end surface of the tip member and the shaft tube body, whereby the grip and the tip are It is possible to prevent the gap between the member, the grip and the shaft main body, and further improve the grip rotation prevention force. Further, since the contact area between the rear end surface of the tip member and the tip end surface of the grip is reduced by the concave groove, it is possible to improve assemblability such as insufficient tightening when the tip member is screwed.

  The present invention was able to provide a writing cylinder that is easily deformed even with a small gripping force for gripping and is equipped with a grip with good assembling ability.

It is a figure which shows one Embodiment of the writing instrument of this invention. FIG. 2 is an enlarged view of a main part, partly omitted in FIG. 1. It is an enlarged view of the grip in FIG. It is a figure which shows j assembly process in which one part was omitted in FIG. It is an AA expanded sectional view in FIG. It is BB expanded sectional drawing in FIG. It is explanatory drawing which shows the writing state of the writing instrument of this invention.

  Next, embodiments of the grip 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 embodiments.

  The shaft 1 of the writing instrument of Example 1 shown in FIGS. 1 to 7 includes an outer shaft 5 in which a front shaft 2 and a rear shaft 3 are screwed together via an intermediate shaft 4 and a clip is integrally provided on the rear shaft 3. And a metal base 7 is detachably screwed to the front end portion of the front shaft 2. In addition, a writing tool in which a grip 6 using a translucent silicone rubber with a Shore hardness of Hs (JIS A) 50 as a soft material is attached to the front shaft 2 and compressed between the base 7 and the intermediate shaft 4 in the axial direction. The shaft cylinder 1 is obtained.

  In this embodiment, a ballpoint pen refill 13 in which a writing pen ink (not shown) is filled in the ink storage cylinder 13 in the rear shaft 3 and a ballpoint pen tip 14 having a ball as a writing medium is mounted on the tip. The ball pen refill 13 is urged and stored in the rear end direction of the rear shaft 3 by the coil spring 8 and includes a projecting / retracting mechanism including a rotating cam 11 disposed in the rear shaft 3, and protrudes from the rear shaft 3. When the knocking body 9 urged rearward by the coil spring is pressed, the push-in rod 10 and the rotating cam 11 actuate the retracting mechanism, and the ball-point pen tip 14 of the ball-point pen refill 13 is maintained protruding from the tip opening 7 a of the base 7. This is illustrated as a knock-type ballpoint pen that can be written.

  The grip 6 has a substantially arc-shaped outer wall inclined portion 6a that gradually increases in diameter in the direction of the front end surface 6d of the grip 6 on the outer wall of the front end portion, and a front end surface 6d of the grip 6 on the inner wall of the grip 6. Three concave grooves 6c extending along the axis J direction of the shaft cylinder main body are formed from the inner wall inclined portion 6b whose inner diameter gradually decreases in the direction and the tip surface 6d of the grip 6, and the concave groove 6c. The widths L1 and L2 of the grip 6 are formed so as to gradually become smaller from the front end surface 6d of the grip 6 toward the rear (L1> L2).

  Since the grip 6 is mounted in a state where the base 7 is screwed and compressed in the axial direction, the front end surface 6d of the grip 6 and the rear end surface 7b of the base 7 and the grip 6 and the step portion 4a of the intermediate shaft 4 are connected. Generation | occurrence | production of a clearance gap between can be suppressed. At this time, since the contact area between the rear end surface 7b of the base 7 and the front end surface 6d of the grip 6 is reduced by the concave groove 6c on the front end surface 6d of the grip 6, insufficient tightening when the base 7 is screwed, etc. Assemblability can be improved.

  Further, since the widths L1 and L2 of the concave groove 6c are gradually reduced from the front end surface 6d to the rear end surface side of the grip 6 (L1> M1), the grip 6 is easy to mount and prevents rotation. By making the thicknesses H1 and H2 of the grips facing the bottom wall of the groove 6c larger than the widths L1 and L2 of the facing grooves 6c (H1> L1, H2> L2), the amount of deformation is reduced. Generation of defects such as distortion and cracks due to repeated deformation can be suppressed without increasing the size more than necessary. Further, by forming the inner wall inclined portion 6b, the thickness of the outer wall inclined portion 6a is increased and the depth of the concave groove 6c is increased, so that the inner wall inclined portion 6b can be easily deformed.

  When writing in detail, when the fingertip 15 holding the grip 6 is brought into contact with the outer wall inclined portion 6a at the tip of the grip 6 and a force (in the direction of arrow a1 in FIG. 2) is applied to the paper surface 16, the outer wall is inclined. Since force also acts from the portion 6a in the axial center J direction (arrow a2 in FIG. 2), the gripping force can be stably held even when the gripping force is small, and the gripping force is formed by the concave groove 6c formed on the inner wall of the grip 6. The grip 6 can be easily deformed even if is small, and a good grip feeling can be obtained.

  In addition, the weight of the writing instrument is not particularly limited. However, when the weight is heavy, specifically, 15 gf or more, a high writing pressure can be obtained even if the writing pressure applied by the user is small. Therefore, it is preferable.

  Examples of the soft material of the present invention include elastically deformable silicone rubber, natural rubber, butyl rubber, fluorine rubber, vinyl chloride resin, butadiene rubber, urethane rubber, polyethylene resin, other synthetic rubbers, thermoplastic elastomers, etc. It can be appropriately selected from among generally known soft materials. In addition, it is preferable to make the grip transparent or translucent because the groove on the inner wall of the grip can be visually recognized from the outside, so that a decorative effect can be obtained.

  Further, if the hardness of the soft material of the present invention is less than 40 in JIS A, the deformation when gripped is large, the writing pressure in the paper surface direction tends to be dispersed, and writing tends to be difficult. Since the grip feeling becomes worse, it is 40 or more and 100 or less, preferably 50 to 80.

  In addition, the shape of the outer wall inclined portion is not particularly limited as long as it gradually increases in diameter toward the tip of the grip, but by making it substantially arc-shaped, it is easy to fit on the fingertip and feels good when gripped. Therefore, it is preferable.

  Further, in the present embodiment, for convenience, the shaft cylinder main body is configured by the front shaft, the intermediate shaft, the rear shaft, and the outer shaft, but the configuration of the shaft tube is particularly limited, such as forming these integrally. is not.

  The length of the concave groove formed on the inner wall of the tip of the grip is not particularly limited as long as it is formed on the inner wall of the tip of the grip. It is preferable to use a concave groove communicating with the rear end surface.

  The shaft tube of the writing tool of the present invention is not limited to the type of the writing body, the knock type, and the cap type, and can be widely implemented as a writing tool in which a grip is attached to the grip portion of the shaft tube.

DESCRIPTION OF SYMBOLS 1 Writing instrument shaft 2 Front shaft 3 Rear shaft 4 Intermediate shaft 5 Outer shaft 6 Grip 6a Outer wall inclined portion 6b Inner wall inclined portion 6c Groove 7 Cap 8 Coil spring 9 Knock body 10 Push rod 11 Rotating cam 12 Ball pen refill 13 Ink storage Tube 14 Ballpoint pen tip 16 Fingertip 16 Paper G Maximum outer diameter L1, L2 Groove width M1, M2 Groove depth H1, H2 Thickness

Claims (4)

In a shaft tube of a writing instrument in which a grip made of a soft material is detachably attached to a grip portion of the shaft tube main body, the diameter gradually increases toward the tip of the grip on the outer wall of the tip of the grip. In addition to forming a sloped outer wall, the inner wall of the tip of the grip has a plurality of grooves extending from the tip end surface of the grip along the axial direction of the shaft cylinder body, and the width of the groove However, the axial tube of the writing instrument is gradually reduced from the front end surface of the grip toward the rear. The shaft cylinder of the writing instrument according to claim 1, wherein the thickness of the grip facing the bottom wall of the concave groove is larger than the width of the concave groove. The shaft cylinder of the writing instrument according to claim 1 or 2, wherein an inner wall inclined portion whose inner diameter gradually decreases toward the tip end face side of the grip is provided on the inner wall of the tip end portion of the grip. A tip member is detachably screwed to a distal end portion of the shaft tube main body, and the grip is compressed and mounted between a rear end surface of the tip member and the shaft tube body. Item 4. The writing instrument shaft according to any one of Items 1 to 3.

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