JP6564701B2 - Writing instrument - Google Patents

Description

The present invention relates to a writing instrument.

Conventionally, in this type of writing instrument, for example, in Patent Document 1, an attachment body formed of rubber, synthetic resin, or the like is fitted into the opening of the shaft tube, and the rubber near the writing portion of an internal mechanism such as a cartridge-type ballpoint pen. A structure is disclosed in which a fitting body formed of synthetic resin or the like is attached, and an inclined surface of the fitting body is closely fitted to an opening of the attachment body.

JP 61-112700 A

The writing instrument of Patent Document 1 has a structure in which a fitting body as a separate part is inserted in the vicinity of a writing portion of an internal mechanism (corresponding to the cartridge of the present application) such as a ballpoint pen. For this reason, there is a possibility that the fitting body and the internal mechanism such as the ballpoint pen are disengaged due to the writing pressure at the time of writing, and the pen tip is immersed in the shaft tube. Moreover, the writing instrument of the said patent document 1 increases manufacturing cost with the number of parts of internal mechanisms, such as a ball-point pen, increasing with a fitting body.

Further, in the writing instrument of Patent Document 1, the inclined surface of the fitting body may bite into the opening of the mounting body of the shaft tube due to the writing pressure at the time of writing, and it may be difficult to remove the internal mechanism such as a ballpoint pen. In addition, since the writing instrument of Patent Document 1 has a structure in which the cap is also fitted to the fitting body, the fitting body may further bite the attachment body due to a strong pushing operation of the cap when the cap is attached, There is a risk of pulling out an internal mechanism such as a ballpoint pen by mistake when removing the cap.

The present invention solves the above-mentioned conventional problems, and there is no fear that the pen tip will be immersed in the shaft tube during writing, and the fitting state between the shaft tube and the cartridge can be changed by writing or removing the cap. Accordingly, it is an object of the present invention to provide a writing instrument that is always easy to remove the cartridge and that can prevent the cartridge from being accidentally pulled out when the cap is removed, and can suppress an increase in the number of parts of the cartridge.

In the present invention, “front” refers to the pen tip side, and “rear” refers to the opposite cartridge side.

The first invention of the present application includes a shaft cylinder 2, a cartridge 3 provided with a pen tip 4 at the front end and detachably attached to the front end opening of the shaft cylinder 2, and a cap 7 attached to the pen tip side. The cartridge 3 includes a pen tip 4, a pen tip holder 5 to which the pen tip 4 is fixed, and an ink storage cylinder 6 to which a rear portion of the pen tip holder 5 is press-fitted and fixed. The pen point holder 5 has a tapered front part 51 to which the pen point 4 is fixed, and an insertion part that is formed behind the tapered front part 51 and has an outer diameter smaller than the rear end of the tapered front part 51. 52, a press-fit portion 53 that is formed behind the insertion portion 52, has an outer diameter smaller than that of the insertion portion 52, and is press-fitted and fixed to the front end opening of the ink containing cylinder 6, and the tapered front portion 51 and a step portion 54 formed between the insertion portion 52. In the state in which the cartridge 3 is inserted into the front end opening of the shaft cylinder 2, the tapered front portion 51 is positioned in front of the front end of the shaft cylinder 2, and the stepped portion 54 is at the front end of the shaft cylinder 2. The outer surface of the insertion portion 52 is detachably fitted to the inner surface of the front end opening of the shaft cylinder 2 and a gripping portion 51a for attaching / detaching the cartridge is formed on the outer surface of the tapered front portion 51. The cap 7 is fitted to the outer surface of the front end portion of the shaft tube 2 in a state where the cap 7 is attached to the pen tip side, and the cap 7 is in a non-contact state with the tapered front portion 51. To do.

Since the writing instrument 1 of the first invention employs the above-described form, the step 54 of the pen tip holder 5 is brought into contact with the front end of the shaft tube 2, so that the pen tip 4 is placed in the shaft tube 2 during writing. Because the cap 7 is in a non-contact state with the tapered front portion 51, the fitting state between the shaft cylinder 2 and the cartridge 3 does not change when the cap is attached and detached, and the cartridge 3 can be easily removed at all times. In addition, there is no possibility that the cartridge 3 is accidentally pulled out when the cap 7 is removed, and an increase in the number of parts of the cartridge 3 is suppressed, and a simple structure is obtained.

The second invention of the present application is characterized in that, in the writing instrument 1 of the first invention, an anti-slip portion is formed in the grip portion 51a.

In the writing instrument 1 according to the second aspect of the present invention, the anti-slip portion is formed on the grip portion 51a, so that the cartridge 3 can be easily attached and detached and can be easily gripped during writing. Specifically, the anti-slip portion includes a concavo-convex portion formed on the surface of the grip portion 51a, or a skin made of an elastic material. Examples of the concavo-convex portion include a plurality of annular convex portions or concave portions, a mesh-shaped convex portion or concave portion, and a plurality of dot-shaped convex portions or concave portions.

There is no risk of the pen tip immersing in the shaft during writing, and the fitting state between the shaft and the cartridge does not change when writing or removing the cap, making it easy to remove the cartridge at all times. There is no risk of pulling out the cartridge from time to time, and an increase in the number of parts of the cartridge can be suppressed.

It is a longitudinal cross-sectional view of embodiment of this invention. It is a principal part expanded longitudinal cross-sectional view of FIG. It is a front view which shows the cartridge of FIG. It is an enlarged front view which shows the pen tip holder of FIG.

Embodiments of the writing instrument of the present invention will be described with reference to the drawings. (See FIGS. 1 to 4)

The writing instrument 1 of the present embodiment includes a shaft tube 2, a cartridge 3 that includes a pen tip 4 at the front end and is detachable from the front end opening of the shaft tube 2, and a cap 7 that is attached to the pen tip side. Is provided.

-Shaft tube The shaft tube 2 is a cylindrical body having both ends made of synthetic resin or metal.

Inner fitting portion An inner fitting portion 21 is formed on the inner surface of the front end opening of the shaft tube 2. The inner fitting portion 21 is composed of an annular smooth surface. An outer fitting portion 52 a of a small diameter portion of the pen tip holder 5 is detachably fitted to the inner fitting portion 21. In addition to the annular smooth surface, the inner fitting portion 21 may be an inward projection (for example, an annular projection, a plurality of point-like projections distributed in a circumferential manner, etc.).

Cap fitting portion A cap fitting portion 22 in which the inner surface of the cap 7 is detachable is formed on the outer surface of the front end portion of the shaft tube 2. The cap fitting portion 22 is formed by an outward projection. The outward projection includes, for example, an annular projection or a plurality of dot-like projections distributed in a circumferential shape. The cap fitting portion 22 may be formed of an annular smooth surface in addition to the outward projection.

Friction member A friction member 8 made of a low-abrasion elastic material (for example, silicone resin, SBS resin, SEBS resin, etc.) is press-fitted and fixed to the rear end opening of the shaft cylinder 2. The friction member 8 thermally discolors the handwriting with frictional heat generated by rubbing the handwriting of the thermochromic ink.

Cartridge The cartridge 3 includes a nib 4, a nib holder 5 to which the nib 4 is fixed to the front part, and an ink containing cylinder 6 to which the rear part of the nib holder 5 is fixed to the front end.

-Pen tip The pen tip 4 employs a ball-point pen tip having a ball held rotatably at the front end.
The ball-point pen tip accommodates a projectile that urges the ball forward and closes the ball to the inner surface of the front edge. By bringing the ball into close contact with the inner surface of the front end edge, ink leakage from the nib 4 and air mixing during writing are prevented. In addition to the ballpoint pen tip, the pen tip 4 may be a marking pen body made of a fiber processed body or a porous body.

-Pen point holder The pen point holder 5 is made of a synthetic resin cylindrical body having both ends opened. The pen tip 4 is fixed to the front end opening of the pen tip holder 5. The rear end portion of the nib holder 5 is press-fitted and fixed to the front end opening of the ink storage cylinder 6.

The outer surface of the pen point holder 5 includes a tapered front portion 51 at the front end portion, and an insertion portion 52 that is formed behind the tapered front portion 51 and has an outer diameter smaller than the outer diameter of the rear end of the tapered front portion 51. And a press-fit portion 53 formed behind the insertion portion 52 and having an outer diameter smaller than the outer diameter of the rear end of the insertion portion 52, and between the tapered front portion 51 and the insertion portion 52. A first step portion 54 to be formed, and a second step portion 55 formed between the insertion portion 52 and the press-fit portion 53 are provided.

1
In a state where the outer surface (outer fitting portion 52a) of the insertion portion 52 is fitted to the inner surface (inner fitting portion 21) of the front end opening of the shaft tube 2, the tapered front portion 51 is more than the front end portion of the shaft tube 2. Located in front. A grip 51a is formed on the outer surface of the tapered front portion 51 when the cartridge is attached or detached (when the cartridge is replaced). The outer diameter of the rear end portion of the tapered front portion 51 is set to be substantially the same as the outer diameter of the front end of the shaft tube 2. Thereby, the area | region of the front-end part outer surface of the axial cylinder 2 of the back can be hold | gripped from the said large diameter part outer surface at the time of writing. The tapered front portion 51 has a front end portion that is tapered.

An anti-slip portion comprising an uneven portion (an uneven portion formed by a plurality of annular protrusions and a plurality of annular grooves) is formed on the surface of the grip portion 51a. Thereby, stable gripping at the time of cartridge attachment / detachment and writing can be performed.

The outer diameter of the rear end portion of the tapered front portion 51 is set to be smaller than the inner diameter of the opening portion of the cap 7 of the shaft tube 2. Thereby, the non-contact state between the inner surface of the cap 7 and the pen tip holder 5 is maintained.

An outer fitting portion 52 a that is detachably fitted to the inner fitting portion 21 on the inner surface of the front end opening of the shaft tube 2 is formed on the outer surface of the insertion portion 52. The outer fitting portion 52a is formed by an annular outward projection. The outer fitting portion 52 a is fitted with the inner fitting portion 21 (annular smooth surface) on the inner surface of the front end opening of the shaft tube 2. In a state where the outer fitting portion 52a is fitted to the inner fitting portion 21 on the inner surface of the front end opening of the shaft tube 2, the first step portion 54 and the front end of the shaft tube 2 are brought into contact with each other in the front-rear direction. The backward movement of the tip holder 5 is restricted. In addition, the outer fitting portion 52a may be an annular smooth surface.

The outer surface of the press-fit portion 53 is formed by an annular smooth surface. The outer surface of the press-fitting portion 53 is press-fitted and fixed to the inner surface of the front end opening of the ink storage cylinder 6. In a state where the outer surface of the press-fitting portion 53 is press-fitted and fixed to the inner surface of the front end opening of the ink storage cylinder 6, the second step portion 55 and the front end of the ink storage cylinder 6 are brought into contact with each other in the front-rear direction.

Ink storage cylinder The ink storage cylinder 6 is a cylindrical body having both ends opened, and is obtained by extrusion molding of a synthetic resin. The outer diameter of the ink containing cylinder 6 is set smaller than the outer diameter of the outer fitting portion 52 a of the insertion portion 52. Thereby, the ink containing cylinder 6 can be smoothly inserted into the front end opening of the shaft cylinder 2. The ink storage cylinder 6 contains ink (water-based or oil-based ink) and a follower (for example, a high-viscosity fluid) that fills the rear end of the ink and moves forward as the ink is consumed. In the present embodiment, preferably, an aqueous thermochromic ink is employed as the ink. The thermochromic ink is preferably a reversible thermochromic ink that changes color or disappears by heating. A tail plug may be fixed to the rear end portion of the ink containing cylinder 6.

Cap The cap 7 is formed of a bottomed cylindrical body having one end opened and the other end closed, and is obtained by a synthetic resin molded body. A fitting portion 71 that can be fitted to the cap fitting portion 22 of the shaft cylinder 2 is formed on the inner surface of the opening of the cap 7. The fitting portion 71 is formed by an inward projection. The inward projections (for example, annular projections, a plurality of dot-like projections distributed in a circumferential manner, etc.) get over and are engaged with the cap fitting portion 22 (outward projection). The fitted portion 71 may be an annular smooth surface in addition to the inward projection.

-Air passage A first air groove 56 in the radial direction is formed in the first step portion 54, and a second air groove 56 is formed on the outer surface of the insertion portion 52 in the front-rear direction communicating with the first air groove 56. An air groove 57 is formed, and an air flow gap 9 communicating with the second air groove 57 is formed between the outer surface of the ink containing cylinder 6 and the inner surface of the shaft cylinder 2. In the state where the cap 7 is removed from the pen tip side and the cartridge 3 is inserted into the shaft cylinder 2, the first air groove 56, the second air groove 57, and the air circulation gap 9 store ink. The air flow between the rear end opening of the tube 6 and the outside air becomes possible.

In the state where the cartridge removal cartridge 3 is inserted into the shaft cylinder 2, the cap 7 is removed from the pen tip side, the outer surface of the shaft tube 2 is gripped by one hand, and the grip portion 51a of the pen tip holder 5 is gripped by the other hand. The cartridge 3 can be removed from the barrel 2 by grasping and pulling.

When the cartridge insertion cartridge 3 is detached from the shaft cylinder 2, when the hand gripping the grip 51 a of the pen tip holder 5 is inserted into the front end opening of the shaft cylinder 2 from the rear end of the ink containing cylinder 6, the pen The first step portion 54 of the tip holder 5 is brought into contact with the front end of the shaft tube 2, and the insertion portion 52 of the pen tip holder 5 is inserted into the inner surface of the front end opening of the shaft tube 2. As a result, the cartridge 3 is inserted into the shaft tube 2.

In the writing instrument 1 according to the present embodiment, the first step portion 54 of the pen tip holder 5 is brought into contact with the front end of the shaft tube 2, so that the pen tip 4 can be prevented from being immersed in the shaft tube 2 during writing. . Further, since the cap 7 is in a non-contact state with the tapered front portion 51, the fitting state between the shaft cylinder 2 and the cartridge 3 is not changed by attaching and detaching the cap, and the cartridge 3 can be easily removed at all times. There is no risk of pulling out the cartridge 3 by mistake when removing the cartridge 7. In addition, an increase in the number of parts of the cartridge 3 can be suppressed and a simple structure can be obtained.

In the writing instrument 1 according to the present embodiment, the anti-slip portion is formed in the grip portion 51a, so that the cartridge 3 can be easily attached and detached and can be easily gripped during writing.

DESCRIPTION OF SYMBOLS 1 Writing instrument 2 Shaft cylinder 21 Inner fitting part 22 Cap fitting part 3 Cartridge 4 Pen tip 5 Pen tip holder 51 Tapered front part 51a Gripping part 52 Insertion part 52a Outer fitting part 53 Press-fit part 54 1st step part 55 Second step portion 56 First air groove 57 Second air groove 6 Ink storage cylinder 7 Cap 71 Fit portion 8 Friction member 9 Air flow gap

Claims (2)

A writing instrument comprising a shaft cylinder, a cartridge provided with a pen tip at the front end and detachable at a front end opening of the shaft cylinder, and a cap attached to the pen tip side,
The cartridge includes a nib, a nib holder to which the nib is fixed, and an ink storage cylinder to which a rear portion of the nib holder is press-fitted and fixed,
The pen point holder includes a tapered front part to which the pen point is fixed, an insertion part formed behind the tapered front part and having an outer diameter smaller than a rear end of the tapered front part, and the insertion part. A press-fit portion that is formed rearward and has an outer diameter smaller than that of the insertion portion and is press-fitted and fixed to the front end opening of the ink storage cylinder, and is formed between the tapered front portion and the insertion portion. A step portion,
In a state where the cartridge is inserted into the front end opening of the shaft tube, the tapered front portion is positioned in front of the front end of the shaft tube, and the stepped portion is brought into contact with the front end of the shaft tube. The outer surface of the part is detachably fitted to the inner surface of the front end opening of the shaft cylinder, and a gripping part at the time of cartridge attachment / detachment is formed on the outer surface of the tapered front part,
The writing instrument, wherein the cap is fitted to an outer surface of a front end portion of the shaft cylinder in a state where the cap is attached to the pen tip side, and the cap is in a non-contact state with the tapered front portion. The writing instrument according to claim 1, wherein an anti-slip portion is formed on the grip portion.

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