JPH0434065Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a ballpoint pen refill having an air circulation hole or groove for adjusting internal pressure in the tail plug that fits into the rear end opening of the barrel.

(Prior Art) An ink storage body loaded into a shaft cylinder is generally formed by covering the circumferential side surface of a large number of filamentous chemical fibers with an outer skin, and the rear end surface is usually exposed. Therefore, if a ballpoint pen refill is subjected to an impact due to a knock operation or a fall accident, the ink in the ink storage body may scatter from the rear end face and enter the air circulation hole or groove of the tail plug, causing ink to leak from there. The internal fibers of the ink storage body protrude from the rear end surface due to the inertia force, which blocks the holes or grooves and causes ink to leak from the ballpoint pen tip at the tip. There were problems such as poor contact. And for the above problems,
○A non-ink filled part is provided at the rear end of the ink absorber.Also, to solve the problem, ○The internal fibers at the rear end of the ink absorber are fixed to each other by welding or adhesive. Traditional technical means exist.
However, in the case of ○B, the writing distance is shortened due to a decrease in the amount of ink filled, and in the case of ○B, the writing distance is short, and the cost increases in the case of ○B. The purpose of the present invention is to solve the above-mentioned drawbacks of (B) and (B) while also solving the problems of (b) and (b).

(Means for Solving the Problems) The ballpoint pen refill of the present application, which was devised to achieve the above object, has an air circulation hole or groove for adjusting internal pressure in the tail plug that fits into the rear end opening of the barrel. In the provided ballpoint pen refill, a cylindrical internal tail plug is attached to the rear end of the ink absorber loaded into the barrel, and covers the rear end surface and the peripheral side of the rear end of the ink absorber. The present invention is characterized in that a protrusion is provided on the inner surface of the stopper or the outer surface of the ink storage body to create a required gap between the outer surface of the ink storage body and the inner surface of the internal tail plug.

(Example) Figures 1 to 3 relate to a ballpoint pen refill according to the first embodiment, in which a tail plug 3 having an air circulation groove 2 is press-fitted into the rear end opening of the barrel 1. Inside the shaft cylinder 1 is a cylindrical ink having a cylindrical shape in which the circumferential side of a bundle of a large number of filamentous chemical fibers is covered with an outer skin 4a, and a relay core 6 connected to the front end to guide the ink to the ballpoint pen tip 5. The ink storage body 7a is loaded, and as shown in FIG. It has a cylindrical shape slightly larger than the diameter, and has rib-like ribs that extend in the axial direction at two opposing locations on the inner surface of its circumferential surface and continue in a U-shape across the inner surface of the rear end surface. An internal tail plug 9a provided with a protrusion 8a is attached to the rear end of the ink storage body 7a as shown in FIG. 1, and as shown in FIGS. A gap 10a communicating with the ink flow groove 2 of the tail plug 3 is provided between the inner surface of the tail plug 9a and the inner surface of the tail plug 9a.

Next, FIG. 4 shows an internal tail plug 9b of a ballpoint pen refill according to a second embodiment, and the structure of the second embodiment is the same as that of the above-mentioned first embodiment except for this internal tail plug 9b. It is. The internal tail plug 9b is formed, for example, by pressing and recessing the outer surface of a metal cylindrical body to provide a protrusion 8b on the inner surface. The internal tail plug 9b can be formed by resin molding similarly to the internal tail plug 9a of the first embodiment, but it can also be formed using a metal material as described above.
The first point is that the protrusion 8b can be formed even in the next processing.
This is different from the internal tail plug 9a of the embodiment. Further, since the concave groove 11 formed on the outer surface can also be used as an air circulation groove, the outer diameter can be expanded until the circumferential surface comes into contact with the inner surface of the shaft cylinder, and there is an advantage that the rear end of the ink storage body can be fixed.

Next, FIG. 5 shows the ballpoint pen refill of the third embodiment, showing an ink storage body 7c and an internal tail plug 9c.
This figure shows how it is installed. The internal tail plug 9c has a simple cylindrical shape without any protrusions on its inner surface, and instead has an outer skin 4c of the ink storage body 7c.
An axial rib-shaped projection 8c is provided on the outer surface of the shaft. In this case as well, a gap 10c is created between the inner surface of the internal tail plug 9c and the outer surface of the ink storage body 7c. The structure other than the ink storage body 7c and the internal tail plug 9c is the same as that of the first embodiment.

In the first to third embodiments described above, the internal tail plug is separate and independent from the tail plug, but an embodiment in which the internal tail plug and the tail plug are integrated is also possible.

(Function) In the ballpoint pen refill of the present application, air guided into the barrel from the air circulation hole or groove of the tail plug is caused by the gap created by the protrusion between the internal tail plug and the ink storage body to Air circulation is ensured by being guided to the rear end surface. When an impact is applied to the ballpoint pen refill due to a knock operation or a fall accident, the protrusion from the rear end surface of the internal fibers of the ink storage body is first blocked by the rear end surface of the internal tail plug; Ink scattered from the rear end surface of the ink storage body is stored in the gap between the internal tail plug and the ink storage body. The ink stored in this gap is again absorbed into the ink storage body from the rear end surface by capillary action.

(Effects of the invention) The structure and operation of the invention are as described above, and it is possible to write after the ink storage body without reducing the ink storage amount of the ink storage body and shortening the writing distance, or without increasing the cost. It prevents ink that has been scattered from the end surface from leaking out of the air circulation holes or grooves of the tail plug, and prevents ink from leaking from the ballpoint pen tip at the tip by blocking the air circulation holes or grooves, and also prevents ink from leaking from the rear end surface of the ink storage body. This has the effect of preventing poor contact with the relay core due to the protrusion of the internal fibers of the pen, and maintaining a good writing condition at all times regardless of external impact.

[Brief explanation of drawings]

Figures 1 to 3 relate to the first embodiment of the present invention, in which Figure 1 is a vertical cross-sectional view of the entire ballpoint pen refill with the middle part omitted, and Figure 2 is a cross-sectional view of the stopper A-A in Figure 1. The cross-sectional view and FIG. 3 are partially cut away perspective views of the internal tail plug. FIG. 4 is a perspective view of the internal tail plug according to the second embodiment of the present invention, and FIG. 5 is a perspective view of the internal tail plug attached to the ink storage body according to the third embodiment of the present invention. 1... shaft cylinder, 2... air circulation groove, 3... tail plug,
4a, 4c...Outer skin of the ink absorbing body, 5...Ballpoint pen tip, 6...Relay core, 7a, 7c...Ink absorbing body, 8a, 8b, 8c...Protrusion, 9a,
9b, 9c...Internal tail plug, 10a, 10c...Gap, 11...Concave groove.

Claims (1)

[Scope of utility model registration request] In a ballpoint pen refill, which has an air circulation hole or groove for adjusting internal pressure in the tail plug that fits into the rear end opening of the barrel, there is a rear end face of the ink absorber at the rear end of the ink absorber loaded into the barrel. A cylindrical internal tail plug that covers the circumferential surface of the rear end is attached, and a required space is provided between the outer surface of the ink storage body and the inner surface of the internal tail plug on the inner surface of the internal tail plug or the outer surface of the ink storage body. A ballpoint pen refill characterized by being provided with a protrusion that causes a .