JPH09156285A - Writing utensil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the number of parts and to simplify assembly by abutting and sticking a flange part nearly orthogonal to the axial center of a mouthpiece fitted to the opening of a barrel cylinder on/to the opening part of a sealing cylinder and closing the tip part containing an air hole on the barrel cylinder side when a cap adheres to the barrel cylinder. SOLUTION: When a cap 10 is fitted to the body of a writing utensil, the tip part containing a penpoint 9 and an air hole 15 enters a sealing cylinder 14. The opening edge part 16 of the sealing cylinder 14 abuts and sticks the flange part 18 of a mouthpiece 17 to seal the air hole 15 and the penpoint 9. Furthermore, the tip part of the penpoint is pushed into the bottom of the sealing cylinder 14 and the bottom is elastically deformed and the ink outflow part of the penpoint 9 is stuck and sealed up. Herein, when the flange part 18 of the mouthpiece 17 abuts and sticks the opening edge part 16 of the sealing cylinder 14, the opening edge part 16 is deformed and the internal cubic volume of the sealing cylinder 14 is made small and the internal pressure of the sealing cylinder 14 is raised. But, when pressing length of the opening edge part 16 of the sealing cylinder 14 corresponding to the flange part 18 of the mouthpiece 17 is made a slight amount, outflow of ink through the air hole 15 is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has an ink tank for directly storing ink without absorbing it into batting or the like, and ink pushed out of the ink tank when the air in the ink tank expands due to a temperature rise or the like. The present invention relates to an improvement in a writing instrument cap provided with an ink reservoir for temporarily retaining ink from dropping from a writing tip or an air hole.

[0002]

2. Description of the Related Art The cap of a conventional direct storage type writing instrument is such that the opening of the sealing tube can be moved in the axial direction so that the volume of the inside of the sealing tube does not change when the cap is removed. The conical surface of the die is abutted and sealed with an appropriate pressing force.

Here, the cap of the writing instrument of the batting system is attached to the shaft cylinder to seal the pen tip and the air hole, but when the cap is attached to the shaft cylinder in order to ensure the sealing, the shaft is attached from immediately before the attachment is completed. Since the inner space of the cap is reduced while the cylinder and the seal portion of the cap are closely fitted and the attachment is completed, the pressure inside the cap is increased and decreased when the cap is attached and detached. However, since the inside of the cap and the latter half of the barrel where the filling is stored are continuous as a space through the air hole of the barrel, the entire writing system of the batting system is pressurized and decompressed as a whole, and the pen tip is attached when the cap is attached or detached. Ink does not flow out from the air holes. However, in the direct storage type writing instrument, the volume in the seal cylinder is not changed when the cap is attached or detached. The air inside is compressed and the air passes through the ink reservoir through the ink reservoir and enters the ink tank as air bubbles, and the ink overflows and is retained in the ink reservoir. On the contrary, when removing the cap from the shaft cylinder, the air in the seal cylinder is decompressed contrary to the above phenomenon, so that the ink in the ink tank is drawn out and is also retained in the ink reservoir. Ink will be pulled out from the pen tip. In this way, each time the cap is attached or removed, the ink retention amount of the ink retention body increases, and finally the retention capacity is exceeded and ink is blown out from the air holes or ink flows out from the pen tip. However, in order to prevent this phenomenon, the above structure is adopted.

[0004]

SUMMARY OF THE INVENTION The cap of the conventional direct storage type writing instrument is a seal which is made of polypropylene or polyethylene and which is relatively hard when the cap is attached and detached so as not to pressurize and decompress and to seal the inside. The structure is complicated and the number of parts is large because the structure is such that the cylinder is movable in the axial direction and the opening edge is in close contact with the conical surface of the base of the writing instrument shaft cylinder. It is also a factor of rising costs. An object of the present invention is to make it possible to provide a cap that solves such a problem.

[0005]

The cap of the writing instrument of the present invention devised to achieve the above-mentioned object is provided with a cup-shaped seal tube made of rubber or the like having a high elasticity in the cap, and the cap is attached to the shaft. When attached to a cylinder, a flange part that is approximately perpendicular to the shaft center of the mouthpiece installed in the shaft cylinder opening comes into close contact with the opening end of the seal cylinder to seal the tip part including the air hole on the shaft cylinder side. When the collar of the mouthpiece contacts the seal tube, the end of the seal tube is compressed and the space inside the seal tube is pressurized, but the compression amount of the seal tube is reduced to a slight amount and the cap is not attached to the shaft. By controlling the position, the above problems are solved without causing any problems in practical use.

[0006]

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 instrument has an ink chamber 2 at the rear of the barrel 1 and an ink reservoir 5 having a number of grooves 3 and a longitudinal groove 4 communicating the grooves 3 on the outer peripheral surface in front.
Is mounted, an ink guide core 7 is inserted through a vertical hole 6 that opens in the axial direction at the center of the ink reservoir 5, and the tip of the ink guide core 7 contacts or sticks to a center core 8. The core 8 is connected to the tip of the pen tip, and ink is supplied from the ink chamber 2 to the pen tip 9 through the ink guide core 7 and the core 8.

Next, the cap 10 is formed with an engaging projection 11 on the inner surface in the vicinity of the opening edge for engaging with the convex portion of the barrel 1. The cap 10 engages with the convex portion 19 of the barrel 1, and the opening end of the cap is It comes into contact with the shaft cylinder step portion 20 and is attached to the shaft cylinder 1 at a fixed position. Further, a stepped portion 12 and a plurality of paddings 13 are formed on the inner wall surface of the cap 10, and a seal tube 14 made of a cup-shaped rubber whose bottom portion is formed thinner than the cylindrical portion is abutted on the stepped portion 12 to form the meat. Cap 1 that fits on the heap 13
Locked in place within 0.

[0008]

In the writing instrument constructed as described above, when the cap 10 is attached to the writing instrument main body, the tip including the pen tip 9 and the air hole 15 enters into the seal tube 14 and the opening edge 16 of the seal tube 14 is removed. The air hole 15 and the nib 9 are sealed by contacting and closely contacting the collar portion 18 of the base 17, and the tip of the nib is pushed into the bottom of the seal tube 14 and the bottom elastically deforms to tightly contact the ink outflow portion of the nib. And seal. Here, when the collar portion 18 of the mouthpiece 17 is brought into contact with and closely adheres to the opening edge portion 16 of the seal cylinder 14, the opening edge portion 16 is deformed and the internal volume of the seal cylinder 14 is reduced, so that the internal pressure in the seal cylinder 14 is increased. If the pressing pressure length of the opening edge 16 of the seal cylinder 14 of the collar 18 of the mouthpiece 17 is set to a slight amount, the inside of the seal cylinder 14 is only slightly compressed, and the ink flows into the reservoir 5. Since the ink that has entered the reservoir 5 returns to the ink chamber when the ink is consumed by writing for practical use, the ink is full in the reservoir 5 and the ink does not flow out from the air hole 15. There is no.

[0009]

The structure and operation of the present invention are as described above, and since it is not necessary to be movable while applying a pressing force in the cap unlike the conventional inner cap, the number of parts is reduced and the assembly is easy. Since it is simple, it is possible to maintain good quality at a low price.In addition, since the tip of the pen tip is also sealed, when the pressure inside the ink chamber rises and the ink is pushed out, Even if the clasp of the mouthpiece becomes inadequate, some ink will only enter the ink reservoir and ink will not leak from the pen tip.

[Brief description of the drawings]

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

FIG. 2 is a cross-sectional view of an AA portion of the cap with the shaft body of FIG. 1 removed.

[Explanation of symbols]

 1 Shaft Cylinder 2 Ink Chamber 3 Circumferential Groove 4 Vertical Groove 5 Ink Reservoir 6 Vertical Hole 7 Ink Induction Core 8 Medium Core 9 Nib 10 Cap 11 Engagement Protrusion 12 Step 13 Cement 14 Seal Cylinder 15 Air Hole 16 Opening Edge 17 Base 18 Collar 19 Convex 20 Shaft Step

Claims (1)

[Claims] 1. An ink direct storage type water-based ballpoint pen having a tank for directly storing ink at the rear of the shaft cylinder and an ink reservoir at the front of the shaft cylinder when a cap is attached to the shaft. The opening end of the seal cylinder made of highly elastic resin or rubber mounted inside the cap is in close contact with the flange surface almost perpendicular to the shaft core of the base mounted in the shaft opening and seals the pen tip A cap for a writing instrument characterized in that the ball of the pen tip and the ink outflow portion of the holder are sealed against the cylinder.