JPH10278481A - Cap of writing utensil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a seal sleeve from coming off the cap even in the case where it is joined with the tip end of a shaft by inserting the seal sleeve in the inner sleeve of the cap, engaging the flange of the seal sleeve to the opening- step part, mount-fixing a fixture sleeve thereon in the cap, and holding the seal sleeve by the inner sleeve and fixture sleeve. SOLUTION: When a cap is mounted on the writing utensil main body, a seal sleeve 15 consisting of elastic rubber or the like is close-contacted with the tip end outer peripheral surface of a chip support by its inside opening periphery 20, and by being close-contacted in contact-pressed relation onto the end part of a mouthpiece and end surface 25 of the seal sleeve 15, the opening part of an air groove is closed. Thus, the seal sleeve 15 comes in close contact with the tip end outer peripheral surface of the chip support and the end part of the mouthpiece with the result that adhesive force exerts the member through self-adhesiveness of the seal sleeve 15; even if the seal sleeve 15 is press-fitted in the inner sleeve 14, it comes off the inner sleeve 14 due to its joint to the shaft side as the cap is detached; however, the flange 16 of the seal sleeve 15 is engaged with the fixture sleeve 18 so that it never comes off the inner sleeve 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for fixing a sealing cylinder made of a resin or rubber having high elasticity for sealing an air port and a pen tip of a writing instrument in a cap.

[0002]

2. Description of the Related Art Conventionally, a sealing cylinder made of rubber or the like having a high elasticity is fixed to a cap of a writing instrument by using an inner cylinder provided inside the cap and having an inner diameter slightly smaller than an outer diameter of the sealing cylinder. It has been fixed by press fitting to a plurality of ribs whose tangent diameter is slightly smaller than the outer diameter of the seal cylinder.

[0003]

In the above-mentioned conventional method of fixing a seal cylinder made of resin or rubber with high elasticity to the inside of a cap of a writing instrument, when the cap is attached to the writing instrument body, the inner edge of the opening of the seal cylinder or The flange is in close contact with the periphery of the air port at the front of the barrel to seal the air port, but the sealing cylinder is made of elastic resin or rubber, etc. There was a problem that it came off the shaft side when the working cap was attached and detached, and came off. An object of the present invention is to make it possible to provide a cap that solves such a problem.

[0004]

In order to achieve the above object, a writing instrument cap according to the present invention, which is devised to achieve the above object, has a sealing cylinder made of highly elastic rubber or the like inserted into an inner cylinder of the cap and an opening step of the inner cylinder. Lock the flange of the seal cylinder to the part, further fix the fixed cylinder in the cap on the seal cylinder, sandwich the seal cylinder with the inner cylinder and the fixed cylinder, and fix the seal cylinder in the cap,
The above problem is solved by preventing the seal cylinder and the shaft from coming off from the cap even if they stick together.

[0005]

FIG. 1 shows an embodiment of the present invention, which will be described in detail with reference to the drawings. The main body of the writing implement has an ink chamber 2 at a rear portion of the barrel 1 and an ink reservoir 5 having a plurality of circumferential grooves 3 and a longitudinal groove 4 for communicating the circumferential grooves 3 on the outer peripheral surface in front.
A vertical hole 6 penetrating in the axial direction is formed at the center of the ink storage body 5, an ink guide core 7 is inserted through the vertical hole 6, and a tip of the ink guide core 7 is The relay core 9 is inserted into the chip 8, and the ink is supplied from the ink chamber 2 to the ball at the tip of the chip 8 through the ink guide core 7 and the relay core 9.

Here, the function of the ink reservoir will be described. The amount of the ink filled in the ink chamber 2 is reduced according to writing, but the reduced air is intermittently formed as bubbles from the circumferential groove 3 through the vertical groove 4. The function of keeping the ink chamber in the ink chamber at a constant pressure, and the air entering the ink chamber expands due to the temperature rise and the decompression of the outside air. The ink is pushed out of the ink chamber by the expansion of the air, and the ink reservoir 5 The ink is stored in the circumferential groove 3 through the vertical groove 4 and has a function of preventing ink from dripping from a pen tip or an air port. Furthermore, if the temperature and the like return to the original state and the air in the ink chamber contracts and returns to the original state, the ink stored in the circumferential groove returns to the ink chamber via the vertical groove 4 and returns to the previous state.

Next, the cap 10 has an engagement projection 12 formed on the inner surface near the opening edge for engaging with the projection 11 of the barrel 1 so as to be engaged with the projection 11 of the barrel 1 and to have the opening end of the cap 10 open. The portion comes into contact with a step portion 13 provided at a front portion of the barrel 1, and is attached at a fixed position to the barrel 1. Further, a stepped inner cylinder 14 is integrally formed in the cap 10,
The inner cylinder 14 has a sealing cylinder 15 made of elastic rubber or the like.
Is inserted into the inner cylinder 14 and the flange 16 of the seal cylinder 15 is
4, and the fixed cylinder 18 is inserted through the cap opening to abut the opening end of the inner cylinder 14, and at the same time, the bulge 19 provided on the inner surface of the cap with respect to the cap 10. Hook the open end of the fixed cylinder 18
The seal tube 15 is fixed between the inner tube 14 and the fixed tube 18 and fixed in the cap 10 by fixing to 0 or press-fitting and fixing to the cap 10.

When the cap 10 is attached, the seal tube 15 made of rubber or the like having a high elasticity first comes into contact with the bottom of the tip 8 to make contact with the tip thereof to seal the ink outflow portion of the chip 8. When the inner opening edge 20 of the seal cylinder 15 is fitted in the middle of the corner radius of the tip end of the chip support 21 and the attachment of the cap 10 is completed, the end face 25 of the seal cylinder 15 comes into contact with the end 24 of the base 23. The inner opening edge 20 of the seal cylinder 15 is brought into close contact with the outer peripheral surface 22 of the tip support 21 while being pressed and adhered, and the opening 27 of the air groove 26 is closed.

[0009]

In the writing instrument constructed as described above, when the cap 10 is attached to the writing instrument body, the seal cylinder 15 made of rubber or the like having a high elasticity has an inner opening edge 20 whose outer peripheral surface at the front end of the tip support 21. 22 and the end 2 of the base 23
The opening 27 of the air groove 26 is closed by abutting and pressing against the end face 25 of the seal cylinder 15 against the end face 4. Thus, the sealing cylinder 15 comes into close contact with the tip outer peripheral surface 22 of the chip support 21 and the end 24 of the mouthpiece 23, and the self-adhesive force of the sealing cylinder 15 acts on the above-mentioned member, so that the sealing cylinder 15 is pressed into the inner cylinder 14. Even when the cap 10 is fitted, when the cap 10 is attached and detached, it may adhere to the shaft side and come off the inner cylinder 14, but the flange 16 of the seal cylinder 15 is caught by the fixed cylinder 18 and does not come off from the inner cylinder 15.

[0010]

The construction and operation of the present invention are as described above. Even if the seal cylinder adheres to the shaft end when the cap is detached, the seal cylinder is caught by the fixed cylinder and does not come off the cap without fail. It becomes possible to mount the seal cylinder in the cap.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a writing instrument of the present invention.

FIG. 2 is a cross-sectional view of the off-axis cap of FIG. 1;

FIG. 3 is a sectional view of a fixed cylinder attached to a cap.

FIG. 4 is a view on arrow A of the fixed cylinder of FIG. 3;

FIG. 5 is a sectional view of the shaft without the cap of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Shaft cylinder 2 Ink chamber 3 Peripheral groove 4 Vertical groove 5 Ink storage body 6 Vertical hole 7 Ink guide core 8 Chip 9 Relay core 10 Cap 11 Convex part 12 Engagement projection 13 Step part 14 Inner cylinder 15 Seal cylinder 16 Flange part Reference Signs List 17 Support rib 18 Fixed cylinder 19 Swelling portion 20 Inner opening edge 21 Chip support 22 Front outer peripheral surface 23 Base 24 End portion 25 End surface 26 Air groove 27 Opening

Claims (1)

[Claims] 1. A cap for a writing implement which stores ink at a rear portion of a barrel and has a pen tip at a tip of a shaft, and is made of an elastic resin or rubber or the like which seals an air port provided at a front portion of the shaft. Insert the resulting seal cylinder into the inner cylinder provided in the cap, then mount the fixed cylinder in the cap above the seal cylinder, fix it in the cap, sandwich the seal cylinder between the inner cylinder and the fixed cylinder, and seal Writing instrument cap that fixes the cylinder inside the cap.