JP2580007Y2 - Writing instrument cap - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a writing instrument cap. More specifically, the present invention relates to a writing instrument cap having an elastic seal portion in the cap body, which is in contact with the pen tip when attached to the writing instrument body and seals the pen tip, and closes a ventilation hole at the top of the cap body.

[0002]

2. Description of the Related Art Conventionally, in a writing instrument cap, ink may leak from an air hole of the writing instrument body by repeatedly pressurizing and depressurizing the inside of the cap by repeatedly attaching and detaching the cap to and from the writing instrument body. The proposal has been made. For example, Japanese Patent Application Laid-Open No. 61-270196 discloses that a vent hole communicating with the outside air is provided at the top of the cap, and a bean cap urged rearward by a spring is confined in the cap movably in the axial direction. There is disclosed a writing instrument cap having a structure in which a resilient seal body that seals a pen tip with the ventilation hole and the inside of the cap when inserted into the writing instrument body is fitted in the miniature cap.

[0003]

The above-mentioned conventional writing instrument cap requires members such as mini-caps and minute compression coil springs, so that the number of parts is large and the structure and assembly work are complicated. As a result, There were problems such as an increase in cost.

The present invention has been made to solve the above-mentioned conventional problems, and does not pressurize or depressurize the inside of the cap even when the attachment and detachment with the writing instrument body are repeated, and further reduces the number of parts and the structure and assembly. An object of the present invention is to provide a writing instrument cap that simplifies work.

[0005]

According to the present invention, an elastic seal portion 31 which comes into contact with a pen tip 43 to seal the pen tip 43 and close the ventilation hole 21 at the top of the cap main body 2 when the pen is attached to the writing instrument body 4 is provided. , A cap 1 of a writing instrument provided in a cap body 2, wherein the elastic seal portion 31, an elastic portion 32 having a self-restoring force and having one end connected to the elastic seal portion 31, and an inner wall of the cap body 2. Body 3 comprising a mounting portion 33 fixed to the other end and connected to the other end of the elastic portion 32
Is mounted in the cap body 2, and the elastic seal portion 31 is provided in the cap body 2 so as to be movable in the axial direction.

[0006]

When the cap 1 is attached to the writing instrument body 4,
The pen tip 43 comes into contact with the rear part of the elastic seal part 31 to be sealed. At the same time, the elastic portion 32 is extended and urges the elastic seal portion 31 rearward. Further, the elastic seal portion 31 is moved forward by the pen point 43 against the urging force of the elastic portion 32. Then, the vent hole 21 at the top of the cap body 2 is closed by the front part of the elastic seal portion 31, and communication with the outside air inside the cap body 2 is cut off.

When the cap 1 is removed from the writing instrument main body 4, the contact of the pen tip 43 with the elastic seal portion 31 is released, and the elastic seal portion 31 is moved rearward by the restoring force of the elastic portion 32. The vent 21 is opened. Then, the inside of the cap body 2 is communicated with the outside air.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.

FIGS. 1 to 3 show a first embodiment. The cap body 2 is a cylindrical body having an open rear end, and a vent hole 21 is provided at the center of the top. On the inner wall of the cap body 2, there are provided an annular projection 22 which fits over the writing instrument body 4 to secure airtightness inside the cap 1 and a steadying projection 23 which slides and engages with the writing instrument body 4. A seal 3 made of soft rubber is mounted on the inner wall of the cap body 2.

The seal body 3 has an elastic seal portion 31, a telescopic portion 32, and a mounting portion 33 integrally formed.

The mounting portion 33 has a cylindrical shape and is in contact with the contact step 25 at the inner part of the cap body 2 and is fitted to the inner wall of the cap body 2.

The elastic seal portion 31 has a curved front portion.
The rear part is formed in a planar shape. When the cap 1 is attached to the writing instrument main body 4, the front portion of the elastic seal portion 31 is in close contact with the air hole 21, and the rear portion of the elastic seal portion 31 seals the pen tip 43. Further, a tapered surface is formed at a rear end edge of the ventilation hole 21, and the elastic seal portion 31 is formed.
Is guided to the center of the ventilation hole 21 so that the elastic seal portion 3
1 is configured to reliably close the ventilation hole 21.

As shown in FIG. 3, the extendable portion 32 is radially extended from the elastic seal portion 31 and comprises four flexible connecting pieces connected to the mounting portion 33. . Since communication holes are provided between the connection pieces, air can be ventilated in the cap body 2 before and after the seal body 3. When attached to the writing implement main body 4, the elastic part 32 is extended and urges the elastic seal part 31 backward.
Note that the tension of the elastic portion 32 is set to be smaller than the fitting force with the writing implement main body 4 so that the cap 1 does not come off after being attached to the writing implement main body 4.

Further, since the elastic seal portion 31 and the expansion and contraction portion 32 are integrally formed by the seal member 3, the elastic seal portion 31 and the expandable portion 32 can be easily mounted in the cap body 2.

The writing implement main body 4 is a direct liquid type writing implement having a pen tip 43 of a conventionally known water-based ballpoint pen, and an ink retaining member 44 disposed between an ink tank at the rear of the barrel and the pen tip 43. At the tip of the barrel, there is provided an annular projection 42 which fits tightly with the cap 1, and an air hole 41 is provided in front of the annular projection 42. The air hole 41 is sealed from the outside air by the annular projection 42. Further, the interior of the cap main body 2 is in communication with the outside air until just before the cap 1 is fitted with the writing implement main body 4. Does not penetrate. When the cap 1 is detached from the writing instrument main body 4, the elastic seal portion 31 is immediately turned off.
Is separated from the vent hole 21, so that the pressure inside the cap body 2 is not reduced. Thereby, even if the attachment / detachment to the writing implement main body 4 is repeated, the ink does not leak from the air holes 41 of the writing implement main body 4.

In this embodiment, a direct liquid type writing instrument having an ink retaining member 44 at the front of the barrel is described.
Although not shown, the present invention is also effective for a writing instrument or the like having a movable stopper that moves forward with the consumption of ink in the ink tank, and can prevent operation failure of the movable stopper due to air intrusion.

FIGS. 4 to 6 show a second embodiment. The cylindrical cap body 2 is provided with a vent hole 21 at the center of the top, a small diameter portion 24 at the inner back, and a contact step 25 at the rear end of the small diameter portion 24. A plurality of ridges 2 in the axial direction are located at positions from the inner wall of the cap 1 slightly behind the abutting step 25 to the abutting step 25 and the inner wall of the small diameter section 24.
6 is extended.

A seal body 3 made of soft rubber is mounted on the inner wall of the cap body 2. The seal body 3 is
The elastic seal portion 31, a thin cylindrical elastic portion 32 extending behind the elastic seal portion 31, and a flange-shaped mounting portion 33 formed at the rear end of the elastic portion 32 are integrally formed.

When the seal body 3 is mounted on the inner wall of the cap body 2, the mounting portion 33 is brought into contact with the contact step 25 to be positioned, and the outer side in the radial direction is fitted by the ridge 26. Be worn. In addition, the protrusion 26 allows ventilation before and after the seal body 3 in the cap body 2.

When the cap 1 is attached to the writing instrument body 4,
The pen tip 43 is buried and sealed in the rear surface of the elastic seal part 31. On the other hand, the front surface of the elastic seal portion 31 is
1 and closes the ventilation hole 21. The elastic portion 32 is extended to urge the elastic seal portion 31 rearward. Other configurations and operations are the same as those of the first embodiment.

FIG. 7 shows a third embodiment. The cap body 2 has a vent hole 21 at the center of the top, a small diameter portion 24 at the inner back,
A contact step 25 is provided at the rear end of the small diameter section 24. A plurality of ridges 26 extend in the axial direction on the contact step 25 and the inner wall of the cap body 2 slightly behind the contact step 25.

A seal 3 is mounted on the inner wall of the cap body 2. The seal body 3 includes a bellows-like elastic portion 32.
At the rear end, a flange-shaped mounting portion 33 is integrally provided by a synthetic resin, and an elastic seal portion 31 made of a rubber material is fixed to a distal end of the elastic portion 32. On the front surface of the elastic seal portion 31, there is provided an annular projection 31a which can be in close contact with the peripheral wall of the ventilation hole 21.

The mounting portion 33 of the seal body 3 is positioned in the axial direction by the ridge 26 and simultaneously fitted in the radial direction. Therefore, ventilation is possible in the cap body 2 before and after the seal body 3. Also, during assembly,
The seal body 3 in which the elastic seal portion 31, the expansion and contraction portion 32, and the attachment portion 33 are integrally formed can be easily attached simply by inserting the seal body 3 from the rear end opening of the cap 1.

[0024]

According to the present invention, the cap of the writing instrument is configured as described above, so that the inside of the cap is not pressurized or depressurized even if the cap is repeatedly attached to and detached from the writing instrument body. In addition, the structure can be simplified and the assembling work can be facilitated.

[Brief description of the drawings]

FIG. 1 is a vertical cross-sectional view of a writing instrument body according to a first embodiment of the present invention, which is not attached to a writing instrument body.

FIG. 2 is a longitudinal sectional view of the first embodiment of the present invention in a state of being attached to a writing instrument main body.

FIG. 3 is a sectional view taken along line AA of FIG. 1;

FIG. 4 is a vertical cross-sectional view of the writing instrument body according to the second embodiment of the present invention, which is not attached to the writing instrument body.

FIG. 5 is a vertical sectional view of the second embodiment of the present invention in a state of being attached to a writing instrument main body.

FIG. 6 is a sectional view taken along line BB of FIG. 4;

FIG. 7 is a longitudinal sectional view of the first embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 cap 2 cap body 21 vent hole 22 annular projection 23 steady rest projection 24 small diameter section 25 contact step 26 ridge 3 seal body 31 elastic seal section 31a annular projection 32 elastic section 33 attachment section 4 writing implement body 41 air hole 42 annular Projection 43 Nib 44 Ink holding member

Claims (1)

(57) [Scope of request for utility model registration] When the electronic device is attached to the writing instrument main body, it comes into contact with the pen tip and seals the pen tip and the cap main body.
The cap 1 of a writing instrument provided with an elastic seal portion 31 for closing the vent hole 21 at the top in the cap body 2, wherein the elastic seal portion 31 has a self-restoring force and one end is connected to the elastic seal portion 31. Telescopic part 32 and cap body 2
A sealing body 3 including a mounting portion 33 fixed to an inner wall and connected to the other end of the elastic portion 32 is mounted in the cap body 2, and the elastic sealing portion 31 is provided in the cap body 2 so as to be movable in the axial direction. Writing instrument cap.