JP7197649B2 - writing instrument - Google Patents

Description

The present invention relates to writing instruments.

Conventionally, in this type of writing instrument, for example, Patent Document 1 discloses that a mounting body formed of rubber, synthetic resin, or the like is fitted to the opening of a barrel, and a rubber body is attached near the writing portion of the internal mechanism of a cartridge-type ballpoint pen or the like. , a structure is disclosed in which a fitting body made of synthetic resin or the like is attached, and an inclined surface of the fitting body is tightly fitted into an opening of the fitting body.

JP-A-61-112700

The writing implement disclosed in Patent Document 1 has a structure in which a fitting body, which is a separate part, is fitted in the vicinity of the writing portion of the internal mechanism (corresponding to the cartridge of the present application) of a ballpoint pen or the like. As a result, there is a risk that the fitting body will be disengaged from the internal mechanism of the ballpoint pen or the like due to writing pressure during writing, and the pen tip will sink into the barrel. In addition, in the writing instrument of Patent Document 1, the fitting body increases the number of parts of the internal mechanism of the ballpoint pen or the like, resulting in an increase in manufacturing cost.

Furthermore, in the writing instrument disclosed in Patent Document 1, the inclined surface of the fitting body bites into the opening of the mounting body of the barrel due to writing pressure during writing, which may make it difficult to remove the internal mechanism of the ballpoint pen or the like. In addition, since the writing instrument of Patent Document 1 has a structure in which the cap is also fitted to the fitting body, there is a risk that the fitting body will further bite into the mounting body due to a strong pushing operation of the cap when the cap is attached. When removing the cap, there is a risk that the internal mechanism such as a ballpoint pen may be pulled out by mistake.

The present invention is intended to solve the above-mentioned conventional problems by eliminating the risk of the pen tip sinking into the barrel during writing, and furthermore, the fitting state between the barrel and the cartridge does not change when writing or attaching and detaching the cap. To provide a writing utensil in which a cartridge can always be easily detached from a cap, the cartridge is not pulled out by mistake when a cap is detached, and an increase in the number of parts of the cartridge can be suppressed.

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

A first invention of the present application comprises a barrel 2, a cartridge 3 having a pen tip 4 at the front end and detachable from the front end opening of the barrel 2, and a cap 7 attached to the pen tip side. wherein the cartridge 3 comprises 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 the rear portion of the pen tip holder 5 is press-fitted and fixed. , the pen tip holder 5 includes a tapered front portion 51 to which the pen tip 4 is fixed, and an insertion portion formed behind the tapered front portion 51 and having an outer diameter smaller than the rear end of the tapered front portion 51. 52, a press-fitting portion 53 formed rearward of the insertion portion 52, having an outer diameter smaller than that of the insertion portion 52, and being press-fitted and fixed to the front end opening of the ink container 6, and the tapered front portion. 51 and the insertion portion 52, and in a state in which the cartridge 3 is inserted into the front end opening of the barrel 2, the tapered front portion 51 is aligned with the barrel 2. 2, the stepped portion 54 abuts against the front end of the barrel 2, the outer surface of the insertion portion 52 is detachably fitted to the inner surface of the front end opening of the barrel 2, and the tapered A grip portion 51a for attaching and detaching the cartridge is formed on the outer surface of the front portion 51, and the cap 7 is fitted to the outer surface of the front end portion of the barrel 2 in a state where the cap 7 is attached to the pen tip side. , the cap 7 is in non-contact with the tapered front portion 51 .

Since the writing instrument 1 of the first aspect of the invention adopts the above configuration, the stepped portion 54 of the pen tip holder 5 is brought into contact with the front end of the barrel 2, so that the pen tip 4 stays within the barrel 2 during writing. Since the cap 7 is in a non-contact state with the tapered front portion 51, the fitting state between the barrel 2 and the cartridge 3 does not change when the cap is attached or detached, and the cartridge 3 can be easily removed at all times. In addition, there is no danger of pulling out the cartridge 3 by mistake 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.

A second invention of the present application is characterized in that, in the writing instrument 1 of the first invention, a non-slip portion is formed on the grip portion 51a.

In the writing instrument 1 of the second aspect of the present invention, the non-slip portion is formed on the grip portion 51a, thereby facilitating attachment and detachment of the cartridge 3 and facilitating gripping during writing. The non-slip portion may be, for example, an uneven portion formed on the surface of the grip portion 51a, or an outer skin made of an elastic material. Examples of the uneven portion include a plurality of annular protrusions or recesses, a mesh-like protrusion or recess, a plurality of dot-like protrusions or recesses, and the like.

There is no danger that the pen tip will sink into the barrel when writing, and the fitting state between the barrel and the cartridge will not change when writing or attaching/detaching the cap, making it easy to remove the cartridge and remove the cap. There is no possibility that the cartridge may be pulled out by mistake, and moreover, an increase in the number of parts of the cartridge can be suppressed.

1 is a longitudinal sectional view of an embodiment of the invention; FIG. FIG. 2 is an enlarged vertical cross-sectional view of a main portion of FIG. 1; FIG. 2 is a front view showing the cartridge of FIG. 1; 2 is an enlarged front view showing the pen tip holder of FIG. 1; FIG.

An embodiment of the writing instrument of the present invention will be described with reference to the drawings. (See Figures 1 to 4)

A writing instrument 1 of this embodiment comprises a barrel 2, a cartridge 3 having a pen tip 4 at the front end thereof and detachable from the front end opening of the barrel 2, and a cap 7 attached to the pen tip side. Prepare.

Axle cylinder The axel cylinder 2 is a cylindrical body made of synthetic resin or metal and having both ends opened.

Inner Fitting Portion An inner fitting portion 21 is formed on the inner surface of the front end opening of the barrel 2 . The inner fitting portion 21 has an annular smooth surface. The outer fitting portion 52a of the small diameter portion of the pen tip holder 5 is detachably fitted to the inner fitting portion 21. As shown in FIG. The inner fitting portion 21 may be an annular smooth surface or an inward projection (for example, an annular projection, a plurality of dotted projections distributed circumferentially, etc.).

• Cap Fitting Portion A cap fitting portion 22 to which the inner surface of the cap 7 is detachable is formed on the outer surface of the front end portion of the barrel 2 . The cap fitting portion 22 is formed by an outward projection. The outward projection is, for example, an annular projection or a plurality of dotted projections arranged circumferentially. The cap fitting portion 22 may be configured by an annular smooth surface instead of the outward projection.

Friction member A friction member 8 made of a low-wear elastic material (eg, silicone resin, SBS resin, SEBS resin, etc.) is press-fitted and fixed to the rear end opening of the barrel 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 pen tip 4, a pen tip holder 5 to which the pen tip 4 is fixed at the front, and an ink container 6 to which the rear of the pen tip holder 5 is fixed at the front end.

- Pen tip As the pen tip 4, a ball-point pen tip with a ball rotatably held at the front end is adopted.
A resilient body is housed within the ballpoint pen tip that urges the ball forward and brings the ball into close contact with the inner surface of the front edge. By bringing the ball into close contact with the inner surface of the front edge, leakage of ink from the nib 4 and entrainment of air during non-writing can be prevented. The pen tip 4 may be a marking pen body made of a fiber processed body or a porous body other than a ball-point pen tip.

- Pen tip holder The pen tip holder 5 is composed of a synthetic resin cylindrical body with both ends opened. A pen tip 4 is fixed to the front end opening of the pen tip holder 5 . The rear end of the pen tip holder 5 is press-fitted and fixed to the front end opening of the ink container 6 .

The outer surface of the pen tip holder 5 includes a tapered front portion 51 at the front end portion and an insertion portion 52 formed behind the tapered front portion 51 and having 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 stepped portion 54 is formed, and a second stepped portion 55 is formed between the insertion portion 52 and the press-fitting portion 53 .

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 barrel 2, the tapered front portion 51 positioned more anteriorly. A gripping portion 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 barrel 2 . As a result, when writing, the area of the outer surface of the front end portion of the barrel 2 behind the outer surface of the large-diameter portion can be gripped. The tapered front portion 51 has a tapered front end portion.

A non-slip portion is formed on the surface of the gripping portion 51a. As a result, it is possible to stably hold the cartridge when attaching/detaching the cartridge and when writing.

Further, 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 of the cap 7 of the barrel 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 is formed on the outer surface of the insertion portion 52 to be detachably fitted to the inner fitting portion 21 on the inner surface of the front end opening of the barrel 2 . The outer fitting portion 52a is formed by an annular outward protrusion. 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 barrel 2 . In a state in which the outer fitting portion 52a is fitted to the inner fitting portion 21 on the inner surface of the front end opening of the barrel 2, the first stepped portion 54 and the front end of the barrel 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 other than this.

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 containing cylinder 6 . In a state in which the outer surface of the press-fit portion 53 is press-fitted and fixed to the inner surface of the front end opening of the ink containing cylinder 6, the second stepped portion 55 and the front end of the ink containing 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 with both ends opened, and is obtained by extrusion molding of synthetic resin. The outer diameter of the ink containing cylinder 6 is set smaller than the outer diameter of the outer fitting portion 52a of the insertion portion 52. As shown in FIG. This allows smooth insertion of the ink container 6 into the front end opening of the barrel 2 . Ink (water-based or oil-based ink) and a follower (for example, high-viscosity fluid) filled at the rear end of the ink and advanced as the ink is consumed are stored in the ink storage cylinder 6 . In this embodiment, the ink is preferably a water-based thermochromic ink. The thermochromic ink is preferably a reversible thermochromic ink that changes color or disappears when heated. 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 with one end open and the other end closed, and is obtained by molding a synthetic resin. A fitted portion 71 that can be fitted to the cap fitting portion 22 of the barrel 2 is formed on the inner surface of the opening of the cap 7 . The fitted portion 71 is formed by an inward projection. The inward projection (for example, an annular projection, a plurality of circumferentially distributed point-like projections, etc.) is overridden and locked to the cap fitting portion 22 (outward projection). The fitted portion 71 may be an annular smooth surface instead of an inward projection.

Air passage A first radial air groove 56 is formed in the first stepped portion 54 , and a second air groove 56 is formed in the outer surface of the insertion portion 52 in the front-rear direction and communicates with the first air groove 56 . An air groove 57 is formed, and an air communication 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 . When the cap 7 is removed from the pen tip side and the cartridge 3 is inserted into the barrel 2, the first air groove 56, the second air groove 57, and the air circulation gap 9 accommodate the ink. Air can flow between the rear end opening of the cylinder 6 and the outside air.

- Cartridge Removal With the cartridge 3 inserted into the barrel 2, remove the cap 7 from the pen tip side, grasp the outer surface of the barrel 2 with one hand, and the grip portion 51a of the pen tip holder 5 with the other hand. The cartridge 3 can be removed from the barrel 2 by grasping and pulling the .

When the cartridge insertion/removal cartridge 3 is detached from the barrel 2, if the grip portion 51a of the pen tip holder 5 is grasped by hand and inserted into the front end opening of the barrel 2 from the rear end of the ink containing barrel 6, the pen The first stepped portion 54 of the tip holder 5 is brought into contact with the front end of the barrel 2 , and the insertion portion 52 of the pen tip holder 5 is attached to the inner surface of the front end opening of the barrel 2 . As a result, the cartridge 3 is inserted into the barrel 2 .

In the writing instrument 1 of the present embodiment, the first stepped portion 54 of the pen tip holder 5 abuts against the front end of the barrel 2, so that the pen tip 4 can be prevented from sinking into the barrel 2 during writing. . In addition, since the cap 7 is in a non-contact state with the tapered front portion 51, the fitting state between the barrel 2 and the cartridge 3 does not change when the cap is removed, and the cartridge 3 can always be easily removed. There is no risk of accidentally pulling out the cartridge 3 when removing the cartridge 7. Moreover, 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 of the present embodiment, the non-slip portion is formed on the grip portion 51a, thereby facilitating attachment and detachment of the cartridge 3 and facilitating gripping during writing.

1 writing instrument 2 barrel 21 inner fitting portion 22 cap fitting portion 3 cartridge 4 pen tip 5 pen tip holder 51 tapered front portion 51a grip portion 52 insertion portion 52a outer fitting portion 53 press-fit portion 54 first stepped portion 55 Second stepped portion 56 First air groove 57 Second air groove 6 Ink storage cylinder 7 Cap 71 Fitted portion 8 Friction member 9 Air circulation gap

Claims (2)

A writing instrument comprising a barrel, and a cartridge having a pen tip at the front end and detachably attached to a front end opening of the barrel,
The cartridge comprises a pen tip, a pen tip holder to which the pen tip is fixed, and an ink container to which the rear portion of the pen tip holder is press-fitted and fixed,
The pen tip holder includes a tapered front portion to which the pen tip is fixed, an insertion portion formed behind the tapered front portion and having an outer diameter smaller than a rear end of the tapered front portion, and the insertion portion. A press-fitting portion formed further rearward, having an outer diameter smaller than that of the insertion portion, and being press-fitted and secured to the front end opening of the ink container, is formed between the tapered front portion and the insertion portion. and a second stepped portion formed between the insertion portion and the press-fit portion and in contact with the front end of the ink container ,
in a state in which the cartridge is inserted into the front end opening of the barrel, the tapered front portion is located forward of the front end of the barrel, and the first stepped portion is in contact with the front end of the barrel; The outer surface of the insertion portion is detachably fitted to the inner surface of the front end opening portion of the barrel, the chamfered portion is provided between the second stepped portion and the rear end of the insertion portion, and the tapered front portion is provided. A gripping portion for attaching and detaching the cartridge is formed on the outer surface of the part ,
An inner fitting part made of an annular smooth surface is formed on the inner surface of the front end opening of the barrel, and the inner fitting part is detachably fitted to the outer surface of the insertion part of the pen tip holder. A writing instrument, characterized in that an outer fitting portion is formed with an outwardly directed projection of . 2. The writing instrument according to claim 1, wherein the grip portion is provided with a non-slip portion.

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