JP4615069B2 - Writing instrument - Google Patents

Description

  The present invention relates to a writing instrument. More specifically, the present invention relates to a writing instrument comprising a shaft cylinder made up of a front shaft and a rear shaft that can be screwed together and a refill accommodated in the shaft cylinder.

  Conventionally, in Japanese Utility Model Publication No. 61-42851, “In a writing instrument that contains an ink storage cylinder and is assembled by screwing the rear shaft and the front shaft, the tail end of the rear shaft is pressed against the tail end of the ink storage cylinder. An ink storage cylinder having a thin-walled annular protrusion that receives the pressure of the portion and a distal end outer peripheral portion that forms a sealing structure by being pressed against the inner tapered surface of the tip shaft by the above-described pressing. It is disclosed.

  In the conventional writing instrument, since the elastically deforming portion at the rear end of the refill that contacts the inner wall of the rear shaft is an annular protrusion, a large amount of elastic deformation cannot be obtained and a large dimensional variation in the axial direction cannot be sufficiently absorbed. .

Japanese Utility Model Publication No. 61-42851

The present invention solves the above-mentioned conventional problems, can sufficiently absorb the dimensional variation in the axial direction of the refill and the shaft tube, and further ensures reliable air inside the refill as the ink is consumed. It is intended to provide a writing instrument that can be captured.

[1] The present invention includes a shaft cylinder 2 composed of a front shaft 3 and a rear shaft 4 that are configured to be screwable with each other, and a pen tip 6 that protrudes outward from a tip hole 34 of the front shaft 3 and The refill 5 is accommodated in the shaft cylinder 2, and a locking wall portion 73 is provided at the front end portion of the refill 5 to be locked with the inner wall of the front shaft, and an air hole is provided at the rear end portion of the refill 5. And an elastically deformable portion that is press-fitted into a rear end opening of the ink containing tube 8 of the refill 5 and is elastically deformable in a radial direction by pressure contact with the inner wall of the rear shaft. The tail plug 9 having 94 is provided (claim 1).

[2] Preferably, the tail plug 9 is press-fitted into the rear end opening of the ink containing cylinder 8, and the rear end surface of the ink containing cylinder 8 connected to the rear of the press-fitted part 92. It is good also as a structure provided with the cyclic | annular collar part 93 to contact | abut, and the elastic deformation part 94 which can be elastically deformed in the radial direction integrally protruding behind the collar part 93 (Claim 2).

(Operation) The tail plug 9 having an elastically deformable portion 94 that is elastically deformable in the radial direction by press contact with the inner wall of the rear shaft is pressed into the rear end of the ink containing cylinder 8 of the refill 5 to thereby elastically deform. Due to the elastic deformation of the portion 94 in the radial direction, the dimensional variation in the axial direction of the refill 5 and the shaft tube 2 can be sufficiently absorbed.

[3] Preferably, the elastic deformation portion 94 of the tail plug 9 may include a plurality of projecting pieces 94 that are integrally projected rearward from the flange portion 93 and elastically deformable in the radial direction. (Claim 3) [4] More preferably, three projecting pieces may be arranged at equal intervals behind the flange (claim 4).

(Operation) Since the elastic deformation portion includes a plurality of projecting pieces 94 protruding rearward from the rear end of the refill 5 and elastically deformable in the radial direction, large elastic deformation in the radial direction can be obtained. And the dimensional dispersion | variation in the axial direction of the axial cylinder 2 can fully be absorbed.

[5] Preferably, a gap 96 is formed between the protrusion 94 and the protrusion 94 so that the inside of the refill 5 and the outside of the refill 5 can be vented through the gap 96 and the air hole 95. Good (Claim 5).

(Operation) In the pressure-contact state with the inner side wall of the rear barrel 4 and the projecting pieces 94 of the rear end of the refill 5, since a gap 96 between the protrusion 94 and the projecting piece 94, the gap 96 and the air Via the hole 95, the inside of the refill 5 and the outside of the refill 5 can be ventilated. Thereby, the air hole 95 for taking in air inside the refill 5 is not closed with ink consumption, and there is no possibility that writing becomes impossible.

[6] In the writing instrument 1 of the claims 1, in the ink accommodating tube 8, and houses an ink 81, a follower 82 advancing with consumption of and the ink 81 is disposed at the rear end of said ink 81 (Claim 6 ) is preferable.

(Operation) In the pressure contact state between the rear end portion of the refill 5 and the inner wall of the rear shaft 4, the air hole 95 at the rear end portion of the refill 5 is not closed, so that the follower 82 is smoothly advanced as the ink 81 is consumed. be able to.

[7] The writing instrument 1 of the claim 1, wherein it is obtained by forming a lubricant layer to the pressure contact portion of the elastic deformation portion 94 and the inner side wall of the rear shaft 4 (claim 7) is preferable.

Thereby, it is possible to smoothly press-contact sliding between the inner side wall of the rear barrel 4 and the resilient deformation part 94, it can be reduced screwing force when screwing operation of the rear axle 4 and front barrel 3, screwing operation To make it easier. The lubricant layer may be formed on either the surface of the elastic deformation portion 94 or the inner wall surface of the rear shaft 4.

Further, as a specific means for forming a lubricant layer to the pressure contact portion of said elastic deformation portion 94 and the inner side wall of the rear shaft 4, for example, lubricants of the elastic deformation portion 94 surface or rear axle 4 or applied to the inner side walls, or, if the elastically deformable portion 94 or the rear shaft 4 made of molded synthetic resin, by adding the lubricant to the synthetic resin material, after the surface or of the elastic deformation portion 94 on the inner side wall of the shaft 94 can be formed a lubricant layer.

The present invention can sufficiently absorb the dimensional variation in the axial direction of the refill and the shaft tube , and can take air into the refill accompanying the consumption of ink.

It is a longitudinal cross-sectional view which shows one Example of this invention. It is an AA line expanded sectional view of FIG. It is a front view of the refill in FIG. FIG. 4 is an enlarged bottom view of the refill of FIG. 3.

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

  One embodiment of the present invention is shown in FIGS. The writing instrument 1 of the present embodiment includes a shaft cylinder 2 composed of a front shaft 3 and a rear shaft 4 that can be screwed together, and a refill 5 that is accommodated in the shaft cylinder 2 in an exchangeable manner.

Front shaft The front shaft 3 is a cylindrical body obtained by injection molding of a synthetic resin (for example, polycarbonate). On the outer surface of the front shaft 3, a small-diameter portion 31 (cap attaching portion), a large-diameter portion 32 (gripping portion) connected to the rear of the small-diameter portion 31, and a rear of the large-diameter portion 32 are connected. A male screw portion 33 is formed. A tip hole 34 is opened at the tip of the small-diameter portion 31, and the nib 6 of the refill 5 accommodated in the shaft cylinder 2 protrudes from the tip hole 34.

On the inner surface of the front shaft 3, there is formed a regulation wall portion that abuts a locking wall portion provided at the tip of the refill 5 and prevents the refill 5 from moving forward. The restriction wall portion includes a plurality of plate-like ribs 35 extending in the axial direction, and an axial air passage is formed between the plate-like ribs 35 and the plate-like ribs 35.

-Rear shaft The rear shaft 4 is a bottomed cylindrical body obtained by injection molding of a synthetic resin (for example, polycarbonate). On the inner surface of the front end opening of the rear shaft 4, a female screw portion 41 to which the male screw portion 33 of the front shaft 3 can be screwed is formed. Further, an inclined wall-like pressing wall portion 42 is formed on the inner surface of the rear end portion of the rear shaft 4 to press the elastic deformation portion (that is, the protruding piece 94) of the tail plug 9 radially inward.

Refill The refill 5 includes a pen tip 6, a pen tip holding cylinder 7 in which the rear portion of the pen tip 6 is press-fitted and held, and an ink storage cylinder in which a rear portion 72 of the pen tip holding cylinder 7 is press-fitted and fixed to the tip opening. 8 and a tail plug 9 press-fitted and fixed to the rear end opening of the ink containing cylinder 8. The ink containing cylinder 8 is filled with an ink 81 (specifically, water-based gel ink) and a grease-like follower 82 that moves forward as the ink 81 is consumed.

-Pen tip The pen tip 6 forms a tip edge and a ball receiving seat by pressing and deforming the tip of a metal pipe (for example, stainless steel pipe) inward, and the tip edge and It is a ball-point pen tip which holds a ball rotatably between a ball seat.

-Pen point holding cylinder The pen point holding cylinder 7 is a cylindrical body obtained by injection molding of a synthetic resin (for example, polypropylene). The pen point holding cylinder 7 is formed between a front part 71 that holds the pen point 6, a rear part 72 that is press-fitted into the front end opening of the ink containing cylinder 8, and the front part 71 and the rear part 72. A flange 73 that abuts on the front end surface of the ink containing cylinder 8 is integrally formed.

  The front surface of the collar portion 73 of the pen tip holding cylinder 7 is engaged with the plate-like rib 35 (that is, the regulating wall portion) on the inner surface of the tip shaft 3 in the axial direction when the refill 5 is accommodated in the shaft cylinder 2. It becomes a stop wall.

  A plurality of ribs 74 extending in the axial direction are formed at equal intervals on the outer surface of the front portion 71 of the pen tip holding cylinder 7, and the ribs 74 are pressed against the inner surface of the tip hole 34 of the tip shaft 3. An air passage is formed between the inner surface 34 and the outer surface of the pen tip holding cylinder 7. Further, a plurality of radial grooves 75 are formed at equal intervals in the collar portion 73 (that is, the locking wall portion) of the nib holding cylinder 7, and the collar portion 73 and the plate-like rib 35 (that is, the regulation wall portion). When is locked, an air passage is formed at the locking point.

-Tail plug The tail plug 9 is a cylindrical body obtained by injection molding of a synthetic resin (for example, polypropylene). On the outer surface of the tail plug 9, there is a small diameter portion 91, a large diameter portion 92 that is connected to the rear of the small diameter portion 91 and press-fitted into the inner surface of the rear end opening of the ink containing cylinder 8, and the large diameter portion 92 A ring-shaped flange portion 93 that is connected to the rear side of the ink-receiving cylinder 8 and abuts against the rear end surface of the ink storage cylinder 8, and a plurality of (specifically, three) protrusions that protrude integrally behind the flange portion 93. 94 (that is, an elastically deformable portion) is integrally formed. In addition, an air hole 95 is provided in the axial center of the tail plug 9 so that the space behind the follower 82 in the ink containing cylinder 8 and the outside of the ink containing cylinder 8 are communicated with each other so as to allow ventilation. The

  The protruding pieces 94 are arranged at equal intervals around the axial air hole 95. The projecting piece 94 is elastically deformed radially inward, with the outer surface thereof being pressed against the inclined pressing wall portion 42 on the inner surface of the rear shaft 4. In addition to the above-described configuration (that is, a configuration in which the pressing wall portion 42 is pressed against the outer surface of the protruding piece 94 and the protruding piece 94 is elastically deformed radially inward), the pressing wall portion 42 is formed on the inner surface of the protruding piece 94. The protrusion 94 may be elastically deformed outwardly in the radial direction.

  The tail plug 9 is formed of a synthetic resin material to which a lubricant is added, and a lubricant layer is formed on the surface of the tail plug 9. As a result, when the front shaft 3 and the rear shaft 4 are screwed together, the projecting piece 94 and the inclined pressing wall portion 42 come into pressure contact with each other while sliding smoothly, so that the screw tightening force can be reduced and the screwing operation can be performed. It becomes easy. In addition, the lubricant layer can prevent the protruding piece 94 from biting against the inclined pressing wall portion 42, whereby the refill 5 can be easily detached from the rear shaft 4, There is no risk of removing the tail plug 9 from the rear end of the refill 5 when it is removed from the shaft.

  Further, in this embodiment, in the state where the refill 5 is accommodated in the shaft cylinder 2, the projecting piece 94 and the projecting piece 94 elastically deformed in the radial direction are not in close contact with each other, and between the projecting piece 94 and the projecting piece 94. This is a configuration having a gap 96. Therefore, the protrusion 94 can be further elastically deformed in the radial direction. Thereby, even if a large writing pressure is applied during writing, the writing pressure can be absorbed by the elastic force of the projecting piece 94.

DESCRIPTION OF SYMBOLS 1 Writing instrument 2 Shaft cylinder 3 Lead shaft 31 Small diameter part 32 Large diameter part 33 Male thread part 34 Tip hole 35 Plate-like rib (regulation wall part)
4 Rear shaft 41 Female thread portion 42 Pressing wall portion 5 Refill 6 Pen tip 7 Pen tip holding cylinder 71 Front portion 72 Rear portion 73 Hook portion (locking wall portion)
74 Rib 75 Groove 8 Ink receiving cylinder 81 Ink 82 Follow-up body 9 Tail plug 91 Small diameter portion 92 Large diameter portion 93 ridge portion 94 Projection piece (elastic deformation portion)
95 Air hole 96 Clearance

Claims (7)

A shaft cylinder composed of a front shaft and a rear shaft that are configured to be screwable with each other, and a refill that includes a pen tip that protrudes to the outside from a tip hole of the front shaft and is accommodated in the shaft cylinder, At the tip of the refill, a locking wall portion that locks with the inner wall of the tip shaft is provided,
It is a cylindrical body made of synthetic resin having air holes at the rear end of the refill , and is press-fitted into the rear end opening of the ink-filling cylinder of the refill and is radially brought into contact with the inner wall of the rear shaft. A writing instrument provided with a tail plug provided with an elastically deformable elastically deformable portion . A portion in which the tail plug is press-fitted into the rear end opening of the ink containing cylinder, an annular collar portion that is provided continuously behind the press-fitted portion and contacts the rear end surface of the ink containing cylinder, and a collar portion. The writing instrument according to claim 1, further comprising: an elastically deformable portion that is elastically deformable in a radial direction and integrally projects rearwardly. The writing instrument according to claim 2, wherein the elastically deforming portion of the tail plug is provided with a plurality of protruding pieces that are integrally protruded rearward from the collar portion and can be elastically deformed in the radial direction. The writing instrument according to claim 3, wherein three projecting pieces are arranged at regular intervals behind the collar. The writing instrument according to claim 3 or 4 , wherein a gap is formed between the protruding pieces and the inside of the refill and the outside of the refill can be vented through the gap and the air hole. The writing instrument according to any one of claims 1 to 5, wherein ink and a follower that is disposed at a rear end of the ink and moves forward as the ink is consumed are accommodated in the ink storage cylinder. Writing instrument according to any one of claims 1-6 comprising forming a lubricant layer to the pressure contact portion between the inner side wall of the rear shaft and the elastic deformation portion.

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