JPH1199791A - Ball-point pen refill - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ball-point pen refill fitted with a valve mechanism for preventing back-flow of ink in which structure is simple and also assembly is easy. SOLUTION: The ball-point pen refill is constituted by connecting an ink- holding tube 1, in which water base ink or gel ink is filled and a back-flow prevention body following together with consumption of ink is arranged in the rear end of ink, to a ball-point pen tip 3 by a joint 2. In this case, a valve chamber 21 provided with a seat part 22, on which a valve ball 23 is seated when writing utensils loaded with the ball-point pen refill are directed upward, is formed in the inside of the joint. A spring 5 is arranged in the inside of a ball-point pen tip and a receiving rod part 51 integrally extended from the tail end of the spring to the direction of an axial line is projected from the opening of the tail end of the ball-point pen tip. When the writing utensils are directed downward, a valve ball 4 abuts on the receiving rod part and is made so as not to abut on an opening 33 of the tail end of the ball-point pen tip.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ballpoint pen refill filled with a low-viscosity aqueous ink or a gel ink having a statically high viscosity but decreasing in viscosity by rotation of a ball.

[0002]

2. Description of the Related Art Unlike a high viscosity oil-based ink, a ball-point pen refill using a low-viscosity water-based ink or a gel ink has a small ink flow resistance and a large amount of ink consumption during writing. To increase the ink storage capacity. Therefore, the ink flows backward due to its own weight or impact and leaks from the tail end opening of the ink storage tube.Therefore, at the rear end of the ink, there is provided a grease-like backflow prevention body that moves following the consumption of ink during writing. It is arranged to prevent backflow of ink.

However, even when such a backflow prevention member is arranged at the rear end of the ink, when the writing implement equipped with the ballpoint pen refill is turned upward, the ink immediately below the ball of the ballpoint pen tip runs out, and air flows into the upper part of the ink storage tube. When the ink enters, the head of the ink directly hits the backflow preventive body, so that the grease-like backflow preventive body is disassembled and no longer serves as a stopper, and ink may leak.

For this reason, a valve mechanism is arranged in a joint for connecting the ball-point pen tip and the ink storage tube, and when the writing instrument is turned upward, the valve mechanism is closed so that the ink head does not fall on the backflow preventer. . In other words, in the joint,
In many cases, a valve chamber having a seat is formed, a valve ball is arranged in the valve chamber, and the valve ball is seated on a seat of the valve chamber when the writing instrument is turned upward.

[0005]

In a ballpoint pen refill having such a valve mechanism, when writing is performed with the writing implement facing downward, when the valve ball dropped from the seat completely blocks the tail end opening of the ballpoint pen tip, the ink drops. Is not supplied, the valve ball must not block the tail end opening of the ballpoint pen tip.

For this reason, conventionally, for example, after a valve ball is inserted into a valve chamber, a cylindrical member having a vertical groove formed on an inner surface thereof is driven into the valve chamber, and when the writing instrument is turned downward, the valve ball is inserted into the cylinder. The ink is supplied to the ball-point pen tip through the vertical groove of the cylindrical member while being in contact with the end of the cylindrical member. However, such a structure has a problem in that the number of parts is increased and assembly is troublesome.

Accordingly, an object of the present invention is to provide a ballpoint pen refill with a valve mechanism for preventing ink backflow, which has a simple structure and is easy to assemble.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a method for fixing a ball-point pen tip at the tip of a joint, filling the tip of the joint with an aqueous ink or gel ink, and consuming ink at a rear end of the ink. In a ball-point pen refill in which an ink storage tube in which a backflow prevention body that follows is disposed is connected to the rear of the joint, a seat portion on which a valve ball is seated when a writing implement equipped with the ball-point refill is turned upward in the joint. Forming a valve chamber having
A spring is arranged in the ball-point pen tip, and a receiving rod part integrally extending in the axial direction from the tail end of the spring projects from the tail-end opening of the ball-point pen tip. So that it does not touch the tail end opening of the ballpoint pen tip.

[0009]

Embodiments of the present invention will be specifically described below with reference to the drawings. In FIG. 1, an ink container 1 and a ballpoint pen tip 3 are connected by a joint 2. The inner diameter of the ink container 1 is about 8 mmφ, which is larger than that of a ballpoint pen made of oil-based ink. The ink container 1 is filled with the ink 11, and the ink 11 is an aqueous ink having a low viscosity or a gel ink having a high viscosity in a static state, but the viscosity is reduced by rotation of a ball. .

At the rear end of the ink 11, a grease-like backflow prevention body 12 is arranged. A piece 13 made of resin having the same specific gravity as the backflow prevention body 12 is provided in the backflow prevention body 12.
Is arranged. The piece 13 is arranged to reinforce the grease-like backflow prevention body 12 when the inner diameter of the ink storage tube 1 is large or when the viscosity of the ink 11 is extremely low, and has a cylindrical shape. However, a rod shape, a cylindrical shape, a cup shape, or the like having an irregular cross section may be used.
The backflow prevention body 12 contacts the rear end surface of the ink 11 and moves following the consumption of the ink 11.

The ball house 3 at the tip of the ballpoint pen tip 3
As shown in FIG. 2, the tip ball 4 is rotatably held inside the ball 2 with a part thereof protruding from the ballpoint pen tip 3. The spring 5 is disposed in the inner hole 33 of the ballpoint pen tip 3,
Presses the tip ball 4. Therefore, at the time of non-writing, the tip ball 4 is pressed against the inward tip edge 31 of the ballpoint pen tip 3 to seal the tip of the ballpoint pen tip 3,
Evaporation and ejection of ink from the tip of the ballpoint pen tip 3 are prevented. A receiving rod portion 51 extending integrally in the axial direction is formed at the tail end of the spring 5, and the receiving rod portion 51 protrudes from the tail end opening 34 of the ballpoint pen tip 3.

The inner hole of the joint 2 is a valve chamber 21.
1 is formed with a tapered seat portion 22 facing the front end. In the valve chamber 21, a valve ball 23 whose outer diameter is slightly smaller than the inner diameter of the valve chamber 21 is disposed so as to be able to move back and forth. That is, a valve mechanism including the valve ball 23 and the seat 22 is incorporated.

When the writing instrument equipped with such a ballpoint pen refill is turned upward, as shown in FIG.
The valve ball 23 sits on the seat 22 and the valve mechanism closes. Therefore, the ink in the ball-point pen tip 3 is not
Stays in the ballpoint pen tip 3 without backflow
The head of the ink 11 in the ink storage tube 1 is
Does not take two. Therefore, the ink does not flow backward and leak from the tail end opening of the ink storage tube 1.

Next, when writing with the writing implement facing downward, as shown in FIG.
3 abuts against the leading edge of the receiving rod 51 protruding from the tail end opening 34 of the ballpoint pen tip 3, but since the outer diameter of the valve ball 23 is slightly smaller than the inner diameter of the valve chamber 21,
There is little room for the valve ball 23 to move left and right, and the valve ball 23 does not fall any further. Therefore, the valve ball 23 does not block the tail end opening 34 of the ballpoint pen tip 3.
For this reason, first, writing becomes possible with the ink remaining in the ball-point pen tip 3, so that “fading” at the beginning of writing does not occur. Since the opening 34 is not closed, the ink in the ink storage tube 1 is supplied into the ballpoint pen tip 3 and writing can be continued.

[0015]

As described above, the ball-point pen refill of the present invention forms a valve chamber having a seat in which a valve ball is seated when a writing instrument having the ball-point pen refill is turned upward in a joint, A spring is placed inside the tip, and a receiving rod part that extends integrally from the tail end of the spring in the axial direction projects from the tail end opening of the ballpoint pen tip, and when the writing instrument is turned downward, the valve ball is attached to this receiving rod part. The back end of the ballpoint pen tip does not come into contact with the tail end opening of the ballpoint pen tip, preventing ink from flowing back due to upward writing or impact.However, the receiving rod that extends in the axial direction from the tail end of the spring points the writing implement downward. Prevents the valve ball from closing the tail-end opening of the ball-point pen tip, thus preventing the valve ball from closing the tail-end opening of the ball-point pen tip Dedicated parts is not required that. Therefore, the number of parts is small, and it is easy to assemble.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a ballpoint pen refill;

FIG. 2 is a cross-sectional view of a main part of the ballpoint pen refill of the present invention, showing a state in which the ballpoint pen refill is directed upward.

FIG. 3 also shows a state in which it is turned downward.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ink accommodating pipe 11 Ink 12 Anti-reflux agent 13 Piece 2 Joint 21 Valve room 22 Seat 23 Valve ball 3 Ballpoint pen tip 31 Inward leading edge 32 Ballhouse 33 Inner hole 34 Ballpoint pen tip tail end opening 4 Tip ball 5 Spring 51 Receiving rod part 52 Straight end part

Claims (1)

[Claims] 1. A tip of a joint is fixed with a ballpoint pen tip, and is filled with aqueous ink or gel ink.
At the rear end of the ink, in a ball-point pen refill in which a follower that follows ink consumption is arranged at the rear end of the ink and connected to the rear of the joint, when the writing implement equipped with the ball-point refill is turned upward in the joint. A valve chamber having a seat portion on which a valve ball is seated is formed, a spring is arranged in the ballpoint pen tip, and a receiving rod portion extending integrally from the tail end of the spring in the axial direction projects from the tail end opening of the ballpoint pen tip. A ballpoint refill characterized in that when the writing instrument is turned downward, the valve ball contacts the receiving rod portion and does not contact the tail end opening of the ballpoint pen tip.