JP2002356085A - Writing utensil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ball-point pen which does not cause an ink leakage even when a ball comes off and does not obstruct an ink discharge during routine writing. SOLUTION: This writing utensil is of such a structure that a communicating porous elastorepulsive body is connected to a ball pressing spring in an ink guide hole.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ball as a writing member using an ink composition, a correction liquid composition, a cosmetic composition or the like, and a ball having a diameter smaller than the diameter of the ball. The present invention relates to a writing implement provided with a ball-point pen tip comprising a ball holder protruding from a portion and arranged in an ink through-hole.

[0002]

2. Description of the Related Art A writing instrument provided with a so-called ball-point pen tip, in which a ball as a writing member is partially protruded from an opening at the tip end of an ink through-hole of a ball holder, and is held in a hollow ink tank such as a pipe. For example, ink containing ink in a free state directly, ink that is impregnated and stored in an ink absorbing material such as a fiber bundle, and the like. There are known ones that supply the ink to the ink through-hole and those that draw out the ink through direct communication of the hole without using an ink relay member. In any case, when writing ink for writing, the ink is discharged from a fine gap between the ball and the tip end opening of the ink through hole of the ball holder.・ The flow characteristics and the ball's own weight prevent the ink from leaking due to the peripheral contact with the vicinity of the tip opening. The ball is positively moved by using a resilient material such as a coil spring. There is also known one that presses it to the vicinity to prevent ink leakage during non-writing. In any case,
The ball of the writing member is still used as a valve for preventing ink leakage during non-writing. Therefore, when a writing implement is dropped or the like is applied by applying an impact or by abrasion caused by rubbing against a rotating ball, the ball may fall out, and there is a problem that ink which is no longer regulated leaks out. . To prevent such an accident, when the ball falls off,
For example, in the invention described in Japanese Patent Application Laid-Open No. H11-34572, a lid member made of rubber, metal, or resin is connected to a coil spring for urging the ball forward. There is disclosed an apparatus in which a ball comes in contact with a valve seat portion provided in an inner step portion of an ink through hole when the ball is dropped.

[0003]

In the case where the lid member as described above is used, since the ink is present in the ink passage hole of the ball holder, the amount of ink flow is substantially restricted.
In order to obtain the fresh handwriting of a ballpoint pen and the smooth writing feel, a wide gap can be obtained even with a small amount of ball movement, such as when widening the gap between the ball that ejects ink and the ball holder during writing and drawing out more ink. In order to form the ball, the holding action of the ball is weak, and the ball easily falls off due to an impact or the like. However, this has been an obstacle to supplying a large amount of ink. SUMMARY OF THE INVENTION It is an object of the present invention to provide a writing instrument which prevents ink leakage when a ball comes off and which does not hinder ink derivation for writing.

[0004]

That is, the present invention comprises a ball as a writing member, and a ball holder which is partially protruded from a tip opening having a diameter smaller than the diameter of the ball and arranged in an ink passage. In a writing instrument having a ballpoint pen tip, a soft communicating porous body and a resilient body for urging the soft communicating porous body forward are arranged in the ink through-hole, and the soft communicating porous body is removed when the ball is removed. Are circumferentially in contact with the ink through-hole and are pressed against the inner wall of the ink through-hole by the urging force of the repellent body and are compressed to close the ink through-hole so that substantially no ink passes through the ink through-hole. The writing instrument is the gist.

[0005] The communicating porous material may be any material having a communicating polynomial that does not hinder the flow of ink in a non-compressed state. Various materials, porosity, pore diameter, hardness, etc. are used depending on the ink used. Can be selected.

When the ball is removed, the elastic body compresses the communicating porous body to close the communicating porous,
It is in circumferential contact with the inner wall of the ball holder to substantially block the ink flow through the ink through hole. For example, it is easy to assemble as a ballpoint pen tip, easy to control the elasticity, and reactivity with ink. In consideration of the influence on the ink circulation, a coil spring can be suitably used. The repellent body may be biased forward by abutting the ball in order to positively make a circumferential contact between the ball and the ball holder during non-writing. In this case, a gap for discharging ink is formed between the ball and the ball holder without hindering the ball from moving backward by the writing pressure at the time of writing and drawing out the ink. The elastic load (elastic force) of the elastic body needs to be appropriately selected in relation to the hardness of the communicating porous body to such an extent that the communicating porous body is compressed.

[0007]

The ink can pass through the inside of the resilient body having the communicating pores, so that the ink ejection in the ink guide hole is not hindered. When the ball falls, the spring extends from the pressed state, that is, the compressed state, toward the tip of the pen tip, thereby crushing the resilient body having the communicating pores, thereby closing the communicating state and closing the ink. prevent.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. The one shown in FIG. 1 is an example of a member called a refill of a so-called knock-type ball-point pen which is used by being housed in a body having a knock mechanism as an exterior body (not shown). A pipe body, which is an extrusion molded product of a polypropylene resin, is used as an ink cylinder 1, and a high viscosity fluid 3 composed of an aqueous ink 2 having shear thinning viscosity and gelled polybutene as a backflow prevention plug, and a floating body 4 immersed in the ink cylinder 1 Accommodating.
The ballpoint pen tip 5 as a pen tip is connected to the ink cylinder 1 via the joint member 6 and is connected to the inner hole of the ballpoint pen tip 5 by ink. In the ballpoint pen tip 5, a coil spring 7 for urging the ball 8 forward is compressed and arranged between the inner step 6a of the joint member and the ball 8 as a writing member in order to suppress ink leakage during non-writing.

As shown in FIG. 2, which is an enlarged view of a portion I in FIG.
The ballpoint pen tip 5 basically includes a ball 8 as a writing member and a ball holder 9 for holding the ball. A tip opening is provided at the tip of an ink through hole 10 which is an inner hole of the ball holder 9. The ball 8 partially projects from 10a. The portion of the ball holder 9 near the tip opening 10a is reduced in diameter so that the tip opening 10a is smaller in diameter than the ball 8 to prevent the ball 8 from coming off. The distal end portion of the coil spring 7 is a linear portion 7a that comes into contact with the ball 8 to urge the ball 8 forward (downward in the figure). This is to allow the ball 8 to pass through the small diameter portion 10b of the ink receiving hole 9a in the portion of the ball receiving seat 9a that controls the retraction of the ball 8, and presses the center position of the ball as much as possible so that the circumferential contact between the ball 8 and the vicinity of the front end opening 10a is achieved. This is to ensure that there is no bias in contact.

A plug member 11 made of porous ether-based polyurethane resin communicates with the linear portion 7a of the coil spring 7.
Are skewered. In a normal state (the state shown in the figure) where the plug member 11 does not receive the repelling force of the coil spring but receives a little but little, the ink can relatively freely pass through the communicating pores and is necessary for writing. It is made so as not to hinder the efficient ink distribution. Such communication pores may be appropriately selected in relation to ink by producing a polyurethane resin by controlling the size of the holes, the number of holes, and the like. Further, by disposing the coil spring 7 in a skewered manner, the coil spring 7 can be handled integrally with the coil spring 7, which is advantageous in assembling the ballpoint pen tip and the writing instrument.

FIG. 3 shows a state in which the ball 8 has been removed by an impact or the like. The coil spring 7 protrudes from the ball holder 9, and the plug member 11 is compressed and deformed between the plug member 11 and the inner step of the ball holder 9. In this state, the pressing force (elasticity) of the coil spring
The communication holes are crushed by this, and the flow of ink is shut off by closing each hole. Therefore, there is no fear of ink leakage even if the ball 8 comes off.

As described above, according to the present invention, when the ball falls off, the repellent body having the communicating hole connected to the spring in the ink guide hole stops the ink flow, so that the ink leakage is prevented, and the ink flow is not normally hindered. You can get a writing instrument.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an example.

FIG. 2 is an enlarged view of a portion I in FIG.

FIG. 3 is a diagram corresponding to FIG. 2, showing an operating state.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ink cylinder 2 Water-based ink 3 High-viscosity fluid 4 Floating body 5 Ballpoint pen tip 6 Joint member 6a Inner step 7 Coil spring 7a Linear part 8 Ball 9 Ball holder 9a Ball receiving seat 10 Ink hole 10a Tip opening 10b Small diameter part 11 stopper Element

Claims (3)

[Claims] 1. A writing implement having a ball-point pen tip comprising a ball as a writing member and a ball holder which is disposed in an ink through-hole by partially projecting from a tip opening having a diameter smaller than the diameter of the ball. In the hole,
A soft communicating porous body and a repellent body for urging the soft communicating porous body forward are arranged, and when the ball is removed, the soft communicating porous body comes into circumferential contact with the ink through hole and the resilient body is repelled. A writing implement characterized in that it is pressed against the inner wall of the ink through-hole by the urging force of the body and is compressed, thereby closing the ink through-hole so that ink does not substantially pass through. 2. The resilient body according to claim 1, wherein the communicating porous body has a hardness of less than 80 as measured by an Asker F-type hardness meter, and the repellent load of the repellent body is 40 mN or more and 300 mN or less. Writing implement. 3. The communication porous body is an ether-based polyurethane resin.
Writing instrument described in.