JPH053346Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Field of Application) The present invention relates to a cap for a writing instrument in which a spherical elastic body is disposed in the inner hole to seal the pen tip.

(Conventional technology) An example is shown in attached Figure 3.

Reference number 1 indicates a cap, and this cap 1
has a spherical elastic body 4 in the small-diameter deep part 3 of the inner hole 2.
are placed so that they do not fall off. Further, reference numeral 5 indicates a pen tip of the main body of the writing instrument, and the tip portion 6 is in contact with the elastic body 4 so as to be somewhat embedded therein.
Here, the use of the spherical elastic body 4 has the advantage that there is no need to pay attention to its directionality when arranging it.

(Problems to be Solved by the Invention) However, in the above-mentioned device, the elastic body is arranged in a substantially fixed state, so it may be damaged. As a result, for example, if the pen tip is pipe-shaped, fragments of the damaged elastic body become clogged within the pen tip, impeding ink discharge. Furthermore, in the case of pens such as fiber pens and resin pens, which do not necessarily have a strong nib, the nib itself may come apart or break.

(Means for Solving the Problems) The present invention provides a cap for a writing instrument in which a spherical elastic body is placed in the inner hole to seal the pen tip, and a protrusion is provided at the inner bottom of the inner hole. In addition to supporting the elastic body, the side wall of the elastic body can be slid on the inner hole wall surface so that the elastic body is also deformed at the contact portion with the protrusion due to the contact force applied to the elastic body from the pen tip when the cap is fitted. The main subject is a writing instrument cap characterized by a support.

(Example) An example is shown in the attached Figure 1. A spherical elastic body 4 is used as described above with reference to FIG. Here, examples of the material of the elastic body 4 include silicone rubber, isoprene rubber, natural rubber, urethane resin, butadiene resin, and the like.

The difference from the one shown in FIG. 3 lies in the presence of a hemispherical protrusion 11 provided at the center of the inner bottom 10 of the inner hole 2 of the cap 1. In the illustrated case, the protrusion 11 is formed integrally with the cap 1, but this protrusion 11
Due to the support by
The portion of contact with the elastic body 4 is also deformed, and the protrusion 11 becomes embedded in the elastic body 4. In addition, in order to satisfy the deformation of the elastic body 4 at this protrusion 11, the elastic body 4
The side wall of the inner hole 2 is slidably supported on the wall surface of the inner hole 2.

This protrusion 11 may be formed in any suitable shape other than a hemispherical shape. However, when sliding to a certain extent, it is preferable that the elastic body 4 is deformed more on the protrusion 11 side than on the nib 5 side. At this stage, it is preferable that the contact area with the elastic body 4 be smaller than that of the pen tip 5. the result,
It does not matter if the elastic body 4 is pierced by the protrusion 11. This is because the amount of piercing helps to absorb variations in the positional relationship between the pen tip 5 and the elastic body 4. The one shown in FIG. 2 is one example, in which the protrusion 11 is formed into a conical shape with a pointed tip. A portion of this pointed tip is stuck into the elastic body 4.

In addition to the above, various modifications may be made, for example, a plurality of ribs may be provided on the wall surface of the inner hole 2 that slidably supports the side wall of the elastic body 4 to suppress sliding resistance. Further, for example, the protrusion 11 may not be provided only at the center of the inner bottom 10 of the inner hole 2 of the cap 1, but may be provided in plurality, or may be shaped like a blade.

(Effects of the invention) The writing instrument cap of the present invention has a spherical elastic body in the inner hole that seals the pen tip, and a protrusion is provided at the inner bottom of the inner hole. In addition to supporting the elastic body, the side wall of the elastic body is slidable on the inner hole wall surface so that the elastic body is also deformed at the part where it contacts the protrusion due to the contact force applied to the elastic body from the pen tip when the cap is fitted. Since the elastic body is supported by the pen tip, the elastic body may be damaged by the pen tip, and the broken pieces of the elastic body may become stuck inside the pen tip and impede the ink ejection performance of the pen tip.
We prevent problems caused by excessive contact between the pen tip and the elastic body, such as the pen tip coming apart or breaking.
This can be sufficiently suppressed without creating a complicated structure.

[Brief explanation of the drawing]

Fig. 1 is a sectional view explaining an example of the present invention;
The figure is a cross-sectional view for explaining another example, and FIG. 3 is a cross-sectional view for explaining the prior art. DESCRIPTION OF SYMBOLS 1...Cap, 2...Inner hole, 3...Reduced diameter inner part, 4...Elastic body, 5...Nib, 6...Nib tip, 10...Inner bottom, 11...Protrusion .

Claims (1)

[Scope of utility model registration request] In a writing instrument cap that has a spherical elastic body in the inner hole that seals the pen tip, a protrusion is provided at the inner bottom of the inner hole, and this protrusion supports the elastic body and also allows the pen tip to close when the cap is fitted. 1. A cap for a writing instrument, characterized in that a side wall of the elastic body is slidably supported on a wall surface of the inner hole so that the elastic body is also deformed at a contact portion with the protrusion due to a contact force applied to the elastic body.