JPH0671164U - Writing crown attachment structure - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a structure for attaching a crown of a writing instrument that can be easily pulled out by hand and does not fall off during transportation. [Structure] An inward projection 5 is provided on an inner peripheral wall of a recess 4 at a rear end of a shaft tube 3. On the other hand, an outward protrusion 2 is provided on the outer peripheral wall of the front portion of the crown 1.
The inward projection 5 and the outward projection 2 are fitted over each other.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a tail crown mounting structure for a writing instrument. More specifically, the present invention relates to a tail cap mounting structure for a writing instrument in which a tail cap is mounted in a recess provided at the rear end of a barrel.

[0002]

[Prior art]

 The conventional tail cap is a decorative element that is mounted in the recess of the rear end of the barrel, and does not require an airtight function like tail plugs, so its mounting is sufficient with a weak fitting force that does not easily slip off. Generally, fitting means such as press fitting has been adopted. (For example, FIG. 3 of Japanese Utility Model Laid-Open No. 3-124895)

[0003]

[Problems to be solved by the device]

 However, the conventional tail crown mounting structure is an easy fitting means such as press fitting in which the outer wall of the tail crown and the inner wall of the recess are frictionally engaged with each other, and the fitting force is weak. The fitting force was loosened due to variations and changes over time, so that it could be easily pulled out by hand, or it might fall out during transportation, transportation, or use.

There is also a risk that an infant may accidentally put the fallen crown in his mouth and clog his throat.

The present invention is intended to solve the above-mentioned conventional problems, and provides a tail cap attachment structure for a writing instrument that can be easily pulled out from a recess and does not fall off during transportation. It is what

[0006]

[Means for Solving the Problems]

 The present invention is a tail cap mounting structure for a writing instrument in which a tail cap 1 is mounted in a recess 4 provided at the rear end of a shaft cylinder 3, and an inward projection 5 is provided on an inner peripheral wall of the recess 4 at the rear end of the shaft cylinder 3, On the other hand, it is required that the outward projection 2 is provided on the front outer peripheral wall of the caudal crown 1 so that the inward projection 5 and the outward projection 2 fit over each other.

The outward protrusion 2 is preferably pressed against the inner peripheral wall of the recess 4 in front of the inward protrusion 5, and the inward protrusion 5 is pressed against the outer peripheral wall of the crown 1 behind the outward protrusion 2. It is preferable to be touched.

Further, it is preferable to provide a guide portion 6 on the inner peripheral wall of the recess 4 behind the inward protrusion 5 with which the outward protrusion 2 is in sliding contact.

The outward protrusions 2 and the inward protrusions 5 may be annular protrusions or a plurality of protrusions arranged circumferentially at appropriate intervals, and these may be appropriately combined. Further, the cross-sectional shape is effectively an arcuate shape, a triangular shape having a taper, a trapezoidal shape, a sawtooth shape, etc., and its size (axial length) is appropriate. Also, of course, the outer diameter (or circumscribed circle diameter) of the outward projection 2 is at least larger than the inner diameter (or inscribed circle diameter) of the inward projection 5.

[0010]

[Action]

 The inward protrusions 5 and the outward protrusions 2 are temporarily elastically deformed in the radial direction when they are fitted over each other. After fitting, the inward projection 5 and the outward projection 2 are locked in the axial direction, so that the crown 1 cannot be easily removed from the recess 4.

Further, the inward projection 5 is pressed against the outer peripheral wall of the caudal crown 1, and the outward projection 2 is pressed against the inner peripheral wall of the concave portion 4, so that the caudal crown 1 is surely fitted in the concave portion 4 after the ride-over fitting. Friction locked to prevent axial rattling. In particular, it is effective when the inward projection 5 and the outward projection 2 are separated from each other without being pressed due to dimensional variation in the axial direction after the overpass fitting.

The guide portion 6 is slidably contacted with the outward protrusion 2 of the caudal crown 1 when the crown 1 is inserted and before the overrunning fitting, and guides the outward protrusion 2 to the contact position with the inward protrusion 5 to ensure the reliability. Enables smooth crossover mating.

[0013]

【Example】

 Embodiments of the present invention will be described with reference to the drawings. The first embodiment is shown in FIGS.

The shaft cylinder 3 is made of a plastic molded body, an ink storage member 7 and a pen tip 8 are attached to a front portion thereof, and an ink tank 31 for storing ink in a raw ink state behind the ink storage member 7. Are formed. The ink storage member 7 is a conventionally known member that temporarily holds the overflow ink according to the fluctuation of the internal pressure of the ink tank 31. Moreover, a ballpoint pen body is adopted as the pen tip 8 here.

A concave portion 4 is integrally formed at the rear end of the shaft cylinder 3 by a cylindrical wall portion 32 extending from the rear end of the shaft cylinder 3 and a bottom wall 33 protruding conically on the ink tank 31 side. To be done. In addition, the crown 1 is mounted in the recess 4 described above.

On the inner peripheral wall of the concave portion 4, a guide portion 6 composed of four vertical ribs 61 arranged near the opening end of the concave portion 4, and an annular inward projection 5 arranged in front of the guide portion 6. Is provided. The vertical rib 61 is composed of a tapered portion 63 at the rear end and a planar sliding contact portion 62 in front of the tapered portion 63, and the inscribed circle diameter of the sliding contact portion 62 does not fit with the outward projection 2 of the crown 1. The diameter of the circumscribed circle of the outward projection 2 is set to be approximately the same.

The tail crown 1 is composed of a collar portion 11 and a cylindrical portion 12, and an annular outward protrusion 2 bulging outward is formed on a front outer peripheral wall of the cylindrical portion 12. The outer diameter of the outward protrusion 2 is larger than the inner diameter of the inward protrusion 5 of the recess 4.

After the tail cap 1 is fitted over the recess 4 and fitted, the outward projection 2 and the inward projection 5 are pressed into contact with each other in the axial direction, and the outward projection 2 is attached to the inner peripheral wall of the recess 4 and the inward projection 5 is The crown 1 is pressed against the outer peripheral wall of the cylindrical portion 12 in the radial direction and frictionally engaged, so that a firm fit that is hard to come off can be achieved. Further, the collar portion 11 of the tail cap 1 contacts the rear end of the barrel 3 and is exposed to the outside. In this embodiment, the crown 1 is made of plastic having the same color as the ink, and allows the color of the ink to be identified from the outside.

Further, in the present embodiment, since the annular outward protrusion 2 is slidably contacting the vertical rib 61 on the inner wall of the recess 4, not only is reliable overpass fitting possible, but also the overpass at the time of insertion. The air in the recess 4 cannot be compressed because the outside air communicates with the inside of the recess 4 until just before the fitting. This enables a smooth insertion without requiring a large force when inserting.

In addition to the ballpoint pen body, the pen nib 8 may be a fountain pen nib, a fiber pen body, a plastic pen body, a small tube pen body, or the like. Further, in the present embodiment, the writing instrument is one in which raw ink is contained in the shaft cylinder 3 in front of the recess 4, but in addition to this, a writing instrument in which an ink storage body is incorporated in the shaft cylinder 3 and a shaft The writing instrument cartridge may be incorporated in the cylinder 3.

A second embodiment is shown in FIGS.

A guide portion 6 including an annular sliding contact portion 62 and an annular tapered portion 63 is provided on the inner peripheral wall of the recess 4, and an annular inward projection 5 is provided in front of the guide portion 6. The bottom wall 33 of the recess 4 also serves as the bottom wall of the ink tank 31, and has a flat surface.

The tail cap 1 is composed of a collar portion 11 and a cylindrical portion 12 continuous with the collar portion 11. On the outer peripheral wall of the cylindrical portion 12, four spherical outward projections 2 are formed at equal intervals. The circumscribed circle diameter of the outward projection 2 is larger than the inscribed circle diameter of the inward projection 5 and is set to be substantially equal to the inner diameter of the guide portion 6. Further, in this embodiment, since the four spherical outward projections 2 and the annular guide portion 6 are in sliding contact with each other, the outside air and the inside of the recess 4 communicate with each other at the time of insertion, so that the inside of the recess 4 is not compressed. As with the first embodiment, smooth insertion is possible.

After the ride-over fitting, the outward projection 2 is pressed and engaged with the inward projection 5 of the concave portion 4 in the axial direction and is pressed against the inner wall of the concave portion 4 to be fitted more firmly. Other configurations are similar to those of the first embodiment.

A third embodiment is shown in FIG. A large-diameter portion 13 (precession portion) is provided at the base of the cylindrical portion 12 of the tail cap 1, and the large-diameter portion 13 is pressed against the guide portion 6 on the inner peripheral wall of the recess 4. This prevents the rattling crown 1 from rattling in the radial direction. Other configurations are similar to those of the first embodiment.

Further, although not shown, also in the crown 1 of the second embodiment, a plurality of protrusions (precession preventing portions) having appropriate intervals are provided at the base of the cylindrical portion 12 in the vicinity of the collar portion 11, and after the crossing over fitting. The projection can be brought into pressure contact with the guide portion 6 on the inner peripheral wall of the recess 4 to suppress radial rattling.

[0027]

[Effect of device]

 According to the present invention having the above-mentioned configuration, even if the radial fitting is loosened due to dimensional variation or aging, it cannot be easily pulled out by hand. Alternatively, it will not fall off during transportation or transportation. In addition, since it does not fall out easily, it is possible to prevent accidents where a baby accidentally puts it in his mouth.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a writing instrument to which a crown mounting structure according to a first embodiment of the present invention is applied.

FIG. 2 is an enlarged vertical sectional view of a main part of FIG.

FIG. 3 is an explanatory diagram showing the state before mounting the caudal crown in FIG. 2;

FIG. 4 is an explanatory diagram showing a process of attaching the tail cap of FIG.

FIG. 5 is an enlarged vertical cross-sectional view of a main part of the second embodiment of the present invention after the crown is attached.

FIG. 6 is an explanatory diagram showing the state before mounting the caudal crown in FIG. 5;

FIG. 7 is an explanatory diagram showing a process of attaching the crown of FIG.

FIG. 8 is an enlarged vertical sectional view of an essential part showing a third embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Crest 11 Collar part 12 Cylindrical part 13 Large diameter part 2 Outward projection 3 Shaft cylinder 31 Ink tank 32 Cylindrical wall part 33 Bottom wall 4 Recess 5 Inward projection 6 Guide part 61 Longitudinal rib 62 Sliding contact part 63 Tapered part 7 Ink Storage member 8 Pen tip

Claims (3)

[Scope of utility model registration request] 1. A tail cap mounting structure for a writing instrument, wherein a tail cap is mounted in a recess provided at a rear end of a shaft cylinder, and a recess 4 at a rear end of the shaft cylinder 3.
An inward projection 5 is provided on the inner peripheral wall, while an outward projection 2 is provided on the front outer peripheral wall of the crown 1, and the inward projection 5 and the outward projection 2 are provided.
A structure for attaching a crown of a writing instrument, which is characterized in that it fits over. 2. The outward protrusion 2 is pressed against an inner peripheral wall of a concave portion 4 in front of the inward protrusion 5, and / or the inward protrusion 5 is pressed against an outer peripheral wall of the crown 1 behind the outward protrusion 2. The structure for attaching the crown of the writing instrument according to claim 1, wherein 3. The inner peripheral wall of the recess 4 at the rear of the inward projection 5,
The tail crown attachment structure for a writing instrument according to claim 1, further comprising a guide portion 6 with which the outward protrusion 2 is in sliding contact.