JP2002103875A - Ball-point pen - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ball-point pen which has a barrel formed of a conventionally used material, instead of a specific material and further, has such advantages that the forcing part of a tip holder is forced to prevent the tip holder from easily coming off, the tip part of the barrel hardly develops cracks and shear-thinning ink is directly packed in the barrel. SOLUTION: The ball-point pen is of such a construction that the tip holder having a fitted ball-point pen tip with a ball housed, in a freely rotating manner, in the tip is mounted by forcing the forcing part into the tip part of the barrel in which the shear-thinning ink and a grease-like follower to follow in accordance with the ink consumption are directly packed, the follower being positioned after the ink. In this ball-point pen, the forcing part of the tip holder is extended in the axial direction and the rear end of the forcing part is positioned at the rear end beyond the gripping part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ball-point pen in which a grease-like follower that directly follows the consumption of ink and the ink having shear thinning viscosity are directly packed in a shaft cylinder.

[0002]

2. Description of the Related Art A ball-point pen of a direct filling type in which ink is directly stored in a shaft cylinder is well known. Recently, ballpoint pens have also been provided as a product in which a shaft cylinder is directly filled with an ink provided with shear thinning viscosity and a grease-like follower that follows the ink as the ink is consumed.

[0003] Most of the structure of such a ballpoint pen is
It has a structure in which a ball-point pen tip having a ball rotatably provided is mounted directly on the tip of a shaft cylinder made of synthetic resin directly filled with ink or on the tip of a chip holder made of synthetic resin.

[0004]

By the way, in the shaft cylinder,
In a ball-point pen containing a low-viscosity aqueous ink, a pen core having a comb groove for temporarily storing the aqueous ink is provided, and a portion of the tip end portion of the barrel that press-fits the press-fit portion of the chip holder is made of ink. No contact. However, in the case where the ink having the shear thinning property is directly packed in the shaft cylinder, the pen core is not provided due to the property of the ink (since the viscosity is high as long as no shear force is applied), and the shaft cylinder is not provided. The portion of the tip of the tip holder into which the press-fitting portion of the chip holder is press-fitted is always in contact with the ink.

[0005] Further, in the latter case where the ink having the shear-thinning property is directly packed in the latter shaft cylinder, the press-fitting portion of the chip holder is press-fitted and firmly press-fitted so that the chip holder does not fall off easily. Since it is made possible, internal stress is always generated at the tip of the barrel, and furthermore, the strength of the resin forming the barrel is deteriorated by the ink, and the former low-viscosity aqueous ink is stored. Cracks are more likely to occur at the tip of the shaft cylinder into which the press-fitting portion of the tip holder is press-fitted. Further, there is also a problem that a stress is applied to the press-fitted portion of the chip holder due to a writing pressure at the time of writing, and a crack is generated at a tip portion of the barrel, and the ink leaks outside from the crack.

In order to solve the above problem, it is conceivable to take measures such as selecting and using a resin having ink resistance which is hardly eroded by ink as a material of the barrel, but increases the manufacturing cost of the barrel. Also, since it is possible to press-fit the press-fitting part of the chip holder and firmly fix it so that it does not easily come off, compatibility with the resin forming the barrel and the resin forming the chip holder Has to be taken into account.

In view of these problems, the present invention can form the shaft cylinder with a conventionally used material, instead of forming the shaft cylinder and the chip holder with specific materials, and further press-fit the press-fit portion of the chip holder. Another object of the present invention is to provide a ball-point pen which is not easily dropped off, hardly generates cracks at the tip end of the barrel, and is directly filled with ink having shear thinning viscosity in the barrel.

[0008]

SUMMARY OF THE INVENTION According to the present invention, there is provided a tip holder having a ballpoint pen tip provided with a ball rotatably provided at a tip thereof, which is provided with an ink having a shear-thinning viscosity inside and an ink consuming portion at a rear portion of the ink. In a ball-point pen having a press-fit portion press-fitted into a tip end of a grease-like follower that is directly packed with a follower and mounted, the press-fit portion of the holder of the chip holder is extended in the axial direction, and the The rear end of the press-fitting portion is located at the rear end from the grip portion of the barrel.

Further, the rear end of the press-fitting portion of the tip holder is located at a rear end of the grease-like follower.

The grip portion according to the present invention is a portion for gripping the shaft cylinder when writing, and a grip member having a grip member or irregularities formed on the grip portion and having a non-slip structure is also known.

[0011]

Embodiments of the present invention will be described with reference to the drawings. Those indicating the same members and the same portions are denoted by the same reference numerals. A ball-point pen 1 according to the first embodiment shown in FIGS. 1 and 2 has a chip holder 3 made of POM resin and a shaft cylinder 2.
Is formed of PC resin. At the front end of the chip holder 3, there is provided a fitting hole 4 communicating with an ink passage 5 opened at the rear end. A ballpoint pen tip 8 having a tip end rotatably provided with a ball 9 is attached to the fitting hole 4, A press-fit portion 3a on the rear end side of the chip holder 3 is mounted by press-fitting on the distal end opening 2a of the cylinder 2. Press-fit part 3 of chip holder 3
a is extended in the axial direction, and the press-fitting portion 3a of the chip holder is provided.
The rear end 3b of the grip member 10 attached to the grip portion H is set at a position closer to the rear end than the rear end 10a.

Inside the barrel 2, an ink 11 having a shear-thinning property and a grease-like follower 12 which comes into contact with the rear end of the ink 11 and follows the consumption of the ink are directly packed. A tail plug 6 having an air hole 7 communicating the inside and the outside of the barrel 2 is attached to the rear end opening 2b of the barrel 2, and ink 11 and a follower 12 are provided at the rear end opening of the barrel. 2b. The grip portion H of the barrel 2 is formed with a small diameter, and the grip member 10 is mounted thereon by two-color molding.

The rear end portion 3b of the press-fit portion of the chip holder 3
Is located on the rear end side of the rear end portion 10a of the grip member 10 (grip portion H), the distance G for press-fitting between the barrel 2 and the chip holder 3 is increased, and leakage of ink can be prevented. it can. In addition, the chip holder does not easily fall off the shaft cylinder even if it is not strongly pressed. Further, since the writing pressure at the time of writing applies a force from the grip portion, the tip of the writing pressure is set by positioning the rear end portion 3b of the press-fit portion on the rear end side from the rear end portion 10a of the grip member 10. Since the stress applied to the press-fit portion 3a of the holder can be dispersed, cracks hardly occur.

To obtain the ballpoint pen 1, a ballpoint pen tip 8 is inserted into the fitting hole 4 at the tip of the tip holder 3, and the press-fit portion 3 a of the tip holder 3 is pressed into the tip of the barrel 3. Then, the barrel 11 is filled with the ink 11 and the follower 12, and the tail plug 6 may be attached to the rear end opening 2b of the barrel 2.

A ball-point pen 21 according to a second embodiment shown in FIG. 3 has a fitting hole in which an ink passage 15 opened at the rear end communicates with the tip of the tip holder 13 in the same manner as the first embodiment. A ballpoint pen tip 8 having a ball 9 rotatably provided at the tip thereof is attached to the fitting hole 14, and a press-fit portion 13 a at the rear end side of the tip holder 13 is further inserted into the tip opening 2 a of the barrel 2. Installed by press fitting. Inside the barrel 2, an ink 11 having a shear thinning property and a grease-like follower 12 which comes into contact with the rear end of the ink 11 and follows the consumption of the ink are directly packed.

The press-fitting portion 13a of the tip holder 13 is further extended in the axial direction than in the first embodiment, and the press-fitting distance G 'between the barrel 2 and the tip holder 13 is made longer.
The rear end portion 13b of the press-fitting portion of the chip holder 13 is located on the rear end side with respect to the rear end portion 12a of the grease-like follower 12.

The rear end 13b of the press-fitting portion of the chip holder
Is positioned on the rear end side of the rear end portion 12a of the grease-like follower 12, so that the ink 11 does not come into contact with the shaft cylinder 2, so that the strength of the resin forming the shaft cylinder 2 due to the ink 11 does not deteriorate. It is preferred.

In this embodiment, for convenience, the chip holder is formed of POM resin and the shaft cylinder is formed of PC resin. However, the present invention is not limited to this. For example, PP resin, PET resin, AS resin and the like are conventionally used. A tip holder or a shaft cylinder can be formed of a material.

[0019]

Since the ball-point pen of the present invention has the above-described structure, the barrel can be formed of a conventionally used material, instead of a specific material, and the press-fit portion of the tip holder can be formed. Was press-fitted, it was not easily dropped off, a crack was hardly generated at the tip of the barrel, and a ballpoint pen directly filled with ink having shear thinning viscosity was obtained in the barrel.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a main part of a ball-point pen according to a first embodiment of the present invention.

FIG. 2 is an enlarged view of a main part in FIG.

FIG. 3 is a cross-sectional view of a main part of a ball-point pen according to a second embodiment of the present invention.

[Theory of code]

 1, 21 Ballpoint pen 2 Shaft barrel 3, 13 Tip holder 3a, 13a Press-fit portion 3b, 13b Rear end of press-fit portion 8 Ballpoint pen tip 9 Ball 10 Grip member 11 Ink 12 Follower 12a Follower rear end portion G, G 'Shaft barrel and tip Press-fit part with holder H Gripping part

Claims (2)

[Claims] 1. A chip holder comprising a ballpoint pen tip having a ball rotatably provided at a tip thereof is provided with an ink having a shear-thinning viscosity inside, and a grease-like follower following the ink with consumption of the ink at a rear portion of the ink. In a ball-point pen in which a press-fit portion is press-fitted into a tip portion of a directly-filled barrel, the press-fit portion of the holder of the chip holder is extended in the axial direction, and the rear end of the press-fit portion of the chip holder is a shaft. A ball-point pen located at a rear end of a holding portion of a cylinder. 2. The ball-point pen according to claim 1, wherein a rear end of the press-fitting portion of the tip holder is located rearward of a grease-like follower.