JPH023901Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a refill tail plug for a writing instrument.

The refill of a ballpoint pen that uses water-based ink contains a batting that absorbs water-based ink inside, and when writing, this ink is transferred to the pen body and consumed, but the amount of air that is commensurate with the amount of ink consumed is enters the refill and is replaced with ink. For this reason, the refill is provided with a ventilation hole, and this ventilation hole is usually provided near the tip of the refill. This is because when the cap is fitted and the pen is placed in a pocket of clothing, the pen body will be in an upward position, so the vent holes should be placed above the batting to prevent ink from flowing out through the vent holes. On the other hand, when using a reflex type writing instrument with a cartridge press, the pen body is in a downward position when worn in a pocket, so if a ventilation hole is provided at the tip, the ink will flow out from this hole. Therefore, it is necessary to provide it at the tail end. Furthermore, since the batting is housed in the tail end, ink would flow out more easily if a ventilation hole were directly punched in the tail end of the refill, unlike the tip. In addition, there is a small gap between the inner surface of the barrel of the writing instrument and the outer surface of the refill body, so if a ventilation hole is provided on the side of the refill body and even a small amount of ink comes out from the outlet of this vent, this ink will flow onto the inner surface of the refill barrel. There is a problem that it adheres and oozes out onto the outer surface of the writing instrument body. For this reason, attempts have been made to provide ventilation grooves in the tail plug that is fitted to the rear end of the refill, but the reality is that nothing that completely satisfies both breathability and liquid tightness has not been achieved. .

Therefore, the purpose of the present invention is to provide a refill tail plug that has a simple structure, satisfies breathability and liquid tightness at the same time, and is suitable for a cap press knob-type writing instrument. An outer mold in which cavities with different inner diameters are formed, and the outer diameters are also different through a step, and the circumferential surface is in close contact with the cavity, and the step is separated or a part of the contact portion remains. It consists of a core that is fitted with the other parts spaced apart, and vertical ventilation holes are formed on the tightly attached peripheral surface.
And, the ventilation holes adjacent to each other through the step are 180 degrees apart from each other.
This is achieved by a tail plug for refill of a writing instrument, which is characterized by being sufficiently spaced apart or by being sufficiently spaced by sandwiching the close contact part of the stepped part.

The present invention will be specifically described below based on embodiments shown in the drawings.

In FIG. 1, the tip of the refill main body 11 has a small diameter, and a ballpoint pen tip 12 is fitted into the opening. A filling 13 is housed inside the refill main body 11, and the filling 13 is held under pinching pressure by the stopper 14 and the tail plug 10. This batting 13 is formed into a rod shape by aligning ultrafine fibers such as polyester, and has a large ink absorbing capacity. is transmitted to.

Here, the tail plug 10 is as shown in FIG.
It consists of two parts: an outer mold 1 and a core 2. The outer mold 1 is fitted into the opening at the tail end of the refil main body 11, and inside thereof two cavities having different inner diameters are formed via two inner steps 3. The core 2 is fitted into this cavity with its circumferential surface in close contact with it, and therefore, the outer diameter of this fitting portion changes sequentially through the outer step portion 4 as well. When mated, the outer step 4
The protrusion 5 contacts the inner step 3 to form a close contact portion, but there is a gap between the other outer step 4 and the inner step 3, forming a circumferential circuit 6. Of course, the circumferential circuit 6 may be a complete circle without forming a close contact portion. A vertical plane part is formed on the outer periphery of the fitting part of the core 2, so that when the core 2 is fitted into the outer mold 1, a ventilation hole 7 with a minute gap is formed in the vertical direction. Here, the plane parts adjacent to each other via the outer step part 4 are spaced apart by 180 degrees, and therefore the ventilation holes 7
are also 180 degrees apart. Therefore, the inside of the refil main body 11 is as follows: ventilation hole 7 → circumferential circuit 6 → ventilation hole 7 →
The circumferential circuit 6 is connected to the outside through the ventilation hole 7. However, it is not necessary that the vent holes 7 adjacent to each other via the circumferential circuit 6 are spaced apart by 180 degrees, and when a close contact portion is formed by the protrusion 5, it is preferable that the close contact portion be sandwiched and spaced apart by 180 degrees or more. .

When the ink in the filling 13 decreases due to writing, an equal amount of air enters the refill main body 11 through the above-mentioned path to keep the internal pressure constant. If the ink falls around the tail plug 10 when the writing instrument is turned in the opposite direction, it tries to exit through the above-mentioned path. However, since the circuit 6 is provided between the adjacent ventilation holes 7, the total length of this route is long, and therefore the ink does not reach the outside. Since the ventilation hole 7 has a half-moon shape, the ink that enters the hole gathers at both ends, and the center part can be ventilated, so that the ventilation is not hindered. Furthermore, even if the ink were to exit through the above-mentioned path, the outlet would be at the center of the tail plug 10 and not at the side of the refill body 11, so it would not adhere to the barrel and would not adhere to the outer surface of the writing instrument body. No oozing.

In this way, the present invention has a circumferential circuit between adjacent vertical ventilation holes, so it is possible to satisfy both breathability and liquid tightness with a simple structure, making it suitable for the pocket-type writing instruments of the cartridge press. It can be used as a tail plug for refills.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of the refill, Fig. 2 is a cross-sectional view of the tail plug, and Figs. 3 to 7 are respectively - of Fig. 2.
It is a sectional view taken along line, - line, - line, - line, - line. 1... Outer mold, 2... Core, 3... Inner section, 4...
...outer section, 6...circuit, 7...ventilation hole, 10...
... Tail plug, 11 ... Refill body, 12 ... Ballpoint pen tip, 13 ... Filling.

Claims (1)

[Scope of utility model registration request] an outer mold in which cavities with different inner diameters are formed through stepped portions, and outer molds with different outer diameters also through the stepped portions, the peripheral surface of which is in close contact with the cavity, and the stepped portions are spaced apart;
Alternatively, it consists of a core that is fitted with a part of the adhesion part remaining and other parts separated, and a vertical ventilation hole is formed on the adhesion periphery, and an adjacent ventilation hole is formed through the step part. A tail plug for a refill of a writing instrument, characterized in that the pores are spaced 180 degrees apart from each other or sufficiently spaced by sandwiching the close contact part of the stepped part.