JP2004322485A - Refill of ball-point pen - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an easily assembled refill of a ball-point pen with a smaller ball diameter, no distinction between the front and the rear of an ink housing tube of which is necessary at assembling and in the tail end opening of the ink housing tube of which an ink filling nozzle can be easily inserted. <P>SOLUTION: In the refill of the ball-point pen, in which a joint 2 having a tip 1 with a rotatably held ball 11 within and being mounted thereto is fittingly attached to the tip opening of a synthetic resin ink housing tube 3, a part 31, which has a diameter larger than the inner diameter of the ink housing tube and to which the joint 2 is fittingly attached, is formed at both the ends of the ink housing tube. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a refill housed in a barrel of a ballpoint pen.
[0002]
[Prior art]
The refill housed in the barrel of the ballpoint pen has a tip that rotatably holds the ball attached to a joint, and this joint is fitted to the opening at the tip of the ink containing tube. The ink container is filled with a so-called gel ink, which has a statically high viscosity and decreases in viscosity due to the shearing force caused by the rotation of the ball, and a grease-like backflow preventing agent is arranged at the tail end of the ink. Many. Then, as the ink is consumed, the backflow preventing agent advances, but the barrel and the ink storage tube are formed of a transparent synthetic resin so that the remaining amount of the ink can be visually checked. Then, when the remaining amount of ink is exhausted, it is replaced with a new refill.
[0003]
The ball size is typically 0.5 mm in diameter for general office ballpoint pens, but due to the diversification of applications for ballpoint pens, balls larger than 0.5 mm or conversely Ballpoint pens using small balls have been put to practical use. Also, the ink storage tube is often used because a transparent PP pipe cut to a predetermined length is inexpensive and easy to manufacture.
[0004]
[Problems to be solved by the invention]
By the way, even if the ball pens have different ball diameters, the shaft cylinder is shared, and thus the outer diameter and length of the ink storage tube are also shared. However, a ball pen having a small ball diameter of, for example, about The amount of ink consumed to write the handwriting length is small. On the other hand, the durability of the tip, which holds the ball freely in rotation, is limited.Thus, despite the small diameter of the ball, the ink reservoir is shared and the same amount of ink as in the case of a ball-point pen with a large ball diameter. When the ink is filled in the ink container, the durability of the chip and the amount of the filled ink cannot be balanced, and the ink may remain even when the durability of the chip is exhausted and writing becomes impossible. Therefore, it is necessary to replace the refill even though the ink is present, and the impression given to the user becomes worse.
In addition, if the ink storage tube is shared with a ball-point pen having a large ball diameter, that is, if the ink filling amount is reduced by using an ink storage tube having a large inner diameter, a long blank space is formed at the tail end of the ink storage tube. In this case as well, there is a disadvantage that the impression given to the user at the time of purchase becomes worse.
[0005]
For this reason, in the case of a ballpoint pen having a small ball diameter, it is necessary to reduce the inner diameter of the ink storage tube. However, a joint shared with a ballpoint pen having a large ball diameter is fitted to the tip opening of the ink storage tube. In addition, it is necessary to form a joint fitting portion having a diameter larger than the inner diameter in the opening at the tip of the ink storage tube. For this reason, at the time of assembling, it is necessary to identify the front and rear of the ink storage tube before assembling. Ink is filled by inserting the ink filling nozzle from the tail end opening of the ink storage tube. However, if the inside diameter of the tail end opening of the ink storage tube is small, it is difficult to insert the ink filling nozzle.
[0006]
Accordingly, the present invention provides a ballpoint pen refill which does not require the front and rear of the ink storage tube to be distinguished at the time of assembly, and in which the ink filling nozzle can be easily inserted into the tail end opening of the ink storage tube and the assembly is easy. Aim.
[0007]
[Means for Solving the Problems]
In order to achieve this object, the present invention provides a refill for a ball-point pen having a small ball diameter, wherein a tip that freely holds the ball is attached to a joint, and the joint is a synthetic resin ink container. In the ball-point pen refill fitted to the distal end opening, a joint fitting portion having a diameter larger than the inner diameter of the ink storage tube is formed at both ends of the ink storage tube.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings. In FIG. 1, a chip 1 formed into a shell shape by stainless steel holds a ball 11 freely in a ball house at the tip thereof. The ball 11 is a sphere made of cemented carbide and having an outer diameter of, for example, 0.38 mmφ, and has a smaller diameter than a standard ball. The ball 11 is pressed against the inward piece at the tip of the tip 1 by the spring 12, and the ball 11 and the inward piece at the tip of the tip 1 constitute a valve mechanism. The tip 1 is fitted in the opening at the end of the joint 2. The joint 2 has a flange portion 21 formed at the center portion, and the tail end side of the flange portion 21 is a fitting portion 22. The joint 2 is common to ballpoint pens having different ball diameters.
[0009]
As shown in FIG. 2, the ink storage tube 3 is formed of a synthetic resin into a cylindrical shape, and the joint fitting portions 31, 31 to which the fitting portions 22 of the joint 2 are fitted at both ends, respectively. Is formed. A low annular projection 32 is formed on the inner peripheral surface of the joint fitting portion 31. When the fitting portion 22 of the joint 2 is fitted, the projection 32 is attached to the outer peripheral surface of the fitting portion 22. It can be firmly fitted by pressing, and the ink does not leak. The outer diameter of the ink storage tube 3 is, for example, 6 mmφ, the inner diameter is 2.5 mmφ, and the inner diameter of the opening of the joint fitting portion 31 is 4.5 mmφ, but the total length and the outer diameter are the same as those of ballpoint pens having different ball diameters. Has become.
[0010]
From the ink storage tube 3 to the inside of the chip 1, the so-called gel ink I, which has a statically high viscosity and decreases in viscosity due to the shearing force due to the rotation of the ball, is filled. Is arranged. Then, as the ink I is consumed by writing, the backflow preventing agent 4 advances.
[0011]
As described above, since the joint fitting portions 31 and 31 are formed at both ends of the ink storage tube 3, there is no directionality before and after the ink storage tube 3, and the fitting portion 22 of the joint 2 is connected with the joint. It is not necessary for the assembling apparatus to distinguish between the front and the rear of the ink storage tube 3 when fitting to the part 31, so that the assembling apparatus can be simplified accordingly. Further, the ink filling nozzle is inserted from the tail end opening of the ink containing tube 3 to fill the ink containing tube 3 with the ink. Has an advantage that the ink filling nozzle can be easily inserted from the tail end opening of the ink storage tube 3 even though the inner diameter of the ink storage tube 3 is small.
[0012]
【The invention's effect】
As described above, the present invention relates to a ball-point pen refill in which a tip having a ball rotatably held therein is attached to a joint and the joint is fitted to a tip opening of a synthetic resin ink containing pipe. Since the joint fitting portion having a diameter larger than the inner diameter of the ink storage tube is formed on both ends of the ink storage tube, it is a refill for a ballpoint pen having a small ball diameter, and it is necessary to identify the front and rear of the ink storage tube at the time of assembly. In addition, it is possible to provide a ball-point pen refill that is easy to insert the ink filling nozzle into the tail end opening of the ink storage tube and easy to assemble.
[Brief description of the drawings]
FIG. 1 is a sectional view of an embodiment of the present invention.
FIG. 2 is a sectional view of an ink storage tube.
[Explanation of symbols]
REFERENCE SIGNS LIST 1 chip 11 ball 12 spring 2 joint 21 flange 22 fitting portion 3 ink storage tube 31 fitting fitting portion 32 annular protrusion 4 backflow inhibitor I ink

Claims (1)

In a ball-point pen refill in which a tip rotatably holding a ball is attached to a joint, and the joint is fitted to a tip opening of a synthetic resin ink storage tube,
A ball-point pen refill, wherein a joint fitting portion having a diameter larger than the inner diameter of the ink storage tube is formed at both ends of the ink storage tube.

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