JP2003231387A - Ball-point pen - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a ball-point pen capable of suppressing the backlash of a pen point and capable of obtaining a good writing feeling. <P>SOLUTION: The ball-point pen comprises a ball-point pen tip 4 having a writing ball 13 held to the leading end thereof in a rotatable manner, a shaft cylinder 1 having a through-hole 14 formed to the leading end thereof to house an ink housing part 17 and constituted so as to protrude the ball-point pen tip 4 from the through-hole 14 and a resin joint for connecting the ball-point pen tip 4 and the ink housing part 17 and having contact parts (5c and 6e) coming into contact with an ink guide hole 12 for guiding ink to the ball-point pen tip 4 and the leading end of the shaft cylinder 1. The contact parts are formed at a plurality of places in an axial direction. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ballpoint pen in which a ballpoint pen refill is housed in a barrel.

[0002]

2. Description of the Related Art Conventionally, as a method of suppressing rattling of a pen tip caused by a gap between a ball-point pen tip and a front opening, an elastically deformable one is disclosed, for example, in Japanese Utility Model Laid-Open No. 6-83376. With multiple vertical taper ribs on the outer circumferential surface of the joint integrally molded with different resin in the outer peripheral direction, and screwing the cap onto the joint vertical ribs, the rattling of the joint rattles inside the cap. Prevent.

However, when the joint is long in the axial (front-rear) direction, there is a high possibility that the nib will rattle due to the bending of the joint member itself. Further, in the case where the joint is divided into a plurality of parts, the pen tip may shake due to the effect of rattling of the fitting portion between the joint members, and the writing feeling during use may be impaired.

[0004]

SUMMARY OF THE INVENTION The present invention solves the above problems and provides a ball-point pen capable of suppressing the rattling of the pen tip and obtaining a good writing feeling.

[0005]

A ballpoint pen of the present invention that achieves the above object has a ballpoint pen tip rotatably holding a writing ball at its tip, a through-hole at its tip, and an ink containing tube inside. A shaft cylinder from which the ballpoint pen tip projects from the through hole, an ink guide hole that connects the ballpoint pen chip and the ink storage tube, and guides ink to the ballpoint pen tip, and abutting contact with the tip of the shaft cylinder. In a ball-point pen including a resinous joint having a portion, the contact portions are formed at a plurality of axial positions. "A plurality of locations in the axial direction" means that the contact portions are provided at different positions that are displaced in the axial direction. The joint is formed by an integrally molded product made of elastically deformable resin or by fitting a plurality of parts. With such a configuration, the pen tip can be fixed at a position displaced in the axial (front-back) direction, so that it is possible to prevent the pen tip from rattling due to the bending that occurs in the joint member itself. In this specification, the front side means the ballpoint pen tip side, and the rear side means the non-ballpoint pen tip side.

The joint is composed of a first joint provided axially forward and a second joint provided axially rearward, and between the first joint and the second joint. A valve chamber is formed, a ball valve is arranged in the valve chamber, and a ball receiving seat with which the ball valve can abut is formed on the ink guide hole of the second joint. It is also preferable to provide a contact portion on each of the second joints. In the case where the joint is divided into multiple parts, the fitting point between the joint members may be affected by rattling, causing the pen tip to shake, which also impairs the writing feel during use. With such a configuration, it is possible to prevent rattling and obtain good writing feeling.

Further, it is preferable that the contact portion is a vertical rib arranged in the axial direction. If the area of the abutting part that comes into contact with the tip of the barrel is large, the amount of deformation of the abutting part will be large, and the force required to deform the abutting part will also be large, and it will take time and effort to replace the ballpoint pen refill, It may occur that the ball can not be fixed sufficiently, causing the ball-point pen refill to rattling. According to the present invention, the force required to deform the contact portion can be reduced, the refill replacement of the ballpoint pen is facilitated, and the ballpoint pen refill can be sufficiently fixed. Furthermore, the use of ribs makes it possible to ensure sufficient air circulation.

Further, it is desirable that the vertical ribs have a tapered shape whose height decreases toward the front. The tapered shape makes it possible to easily prevent the influence of dimensional variation in the axial direction.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention is shown in FIGS. 1, 2 and 3. Referring to FIG. 1, the ball-point pen of the present invention includes an outer cylinder 15 which is a cylindrical rod whose front and rear are open, and an outer cylinder 1.
The ball-point pen refill 3 is housed in the outer cylinder 15 by the front opening 2 screwed to the tip of the ball. In the present embodiment, the shaft cylinder 1 is composed of the front port 2 and the outer cylinder 15.
The front port 2 is not always necessary, and may be a component integrated with the outer cylinder 15. The shaft cylinder 1 is provided at an appropriate position.
The ventilation hole or the ventilation groove is provided by forming a ventilation hole that communicates with the inside of the, or by providing a groove in the screwed portion to which the front port 2 is fixed. Tail plug 11 press-fitted and fixed to the rear end of the outer cylinder 15
A ventilation hole communicating with the inside of the shaft cylinder can be provided (not shown). The method of fixing the front port 2 is not limited to screwing, but press-fitting fixing or the like may be used.

Although various kinds of ink can be used in the ink containing tube 7, the ink has a high static viscosity, and the viscosity is lowered by the rotation of the ball during writing, so that the ink can flow out. The shear thinning ink 8 is contained, and the rear end thereof is filled with a grease-like follower 9 that is movable as it contacts the ink surface and moves following the exhaustion of the ink. The ink containing tube 7 is made of, for example, transparent PP that suppresses ink evaporation.
Resin molded products are used.

FIG. 2 is a longitudinal sectional view of an essential part showing the periphery of the ball-point pen tip of the first embodiment shown in FIG. Tip 2
Is made of metal and has a conical shape with open front and rear ends, and an annular front port inner step portion 2a is formed on the inner peripheral surface so as to have a smaller diameter toward the front. Also, pipe type (needle type)
The ball-point pen tip 4 is press-fitted and fixed to the first joint 5. The first joint 5 is fitted to the second joint 6 via a first joint fitting cylinder portion 5a provided at the rear end. At this time, the first joint flange portion 5d comes into contact with the tip of the second joint 6 and its rearward movement is restricted. The second joint 6 is also fitted in the ink containing tube 7. Also at this time, the second joint flange portion 6d comes into contact with the tip of the outer cylinder 15 to restrict the rearward movement. Both the first joint 5 and the second joint 6 are made of elastically deformable synthetic resin. The front opening 2 can also be made of resin.

A valve chamber 6b is provided between the first joint 5 and the second joint 6.
Is equipped with the ball valve 10, and the first joint 5
A notch 5b is provided at the rear end. In the writing state with the ballpoint pen tip 4 facing downward, the ball valve 10 contacts the first joint 5, and the ink flows into the ballpoint pen tip 4 with the rear end notch 5b of the first joint 5 as a gap.
Further, when the ballpoint pen tip 4 is directed upward, the ball valve 10 comes into contact with the ball seat 6c in the second joint 6 to seal the ink flow path. No movement to the side occurs. Therefore, backflow is prevented.

The front opening 2 is screwed to the outer cylinder 15, and the height decreases toward the front, which is an abutting portion provided on the outer circumference of the second joint, on the front opening inner step portion 2a behind the front opening 2. The taper-shaped second joint vertical ribs 6e are made to come into contact with each other in a biting manner, and the front end inner step portion 2a in front of the front end 2 is elevated toward the front which is an abutting portion provided on the outer periphery of the first joint 5. The first joint vertical ribs 5c, which decrease in height, are brought into abutment with each other. In the present embodiment, the contact portions are provided at a plurality of locations (two locations) that are displaced in the axial (front-back) direction, but two or more locations may be provided.
With such a configuration, rattling can be easily prevented, and a good writing feeling can be obtained. still,
In the present embodiment, the joint is shown to be formed by two parts, but it is naturally possible to provide a plurality of abutting parts on one part in the axial direction.

FIG. 3 is a longitudinal sectional view of an essential part showing the periphery of the ball-point pen tip of the second embodiment of the present invention. In the second embodiment, the first joint 5 has a constant height on the outer peripheral surface of the first joint 5.
The joint vertical rib 5c is provided so as to extend in the axial direction, and the first joint rib 5c is in contact with the inner peripheral surface of the straight through hole 14 of the front end 2. Other than this, it is the same as the second embodiment shown in FIG. Also in this case, rattling can be easily prevented, and a good writing feeling can be obtained. The ribs may be arranged in the reverse direction. That is, the vertical ribs having a certain height can be provided on the second joint 6 and the tapered vertical ribs can be provided on the first joint 5. Further, vertical ribs having a constant height can be provided on both the first joint 5 and the second joint 6.

[0015]

According to the present invention, it is possible to provide a ballpoint pen capable of suppressing rattling of the pen tip and obtaining a good writing feeling.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a first embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of an essential part showing the vicinity of the ball-point pen tip of the first embodiment shown in FIG.

FIG. 3 is a longitudinal sectional view of an essential part showing the vicinity of the ball-point pen tip of the second embodiment of the present invention.

[Explanation of symbols]

1-axis cylinder 2 tip 2a Front end inner step 3 ballpoint refill 4 ballpoint pen tip 5 first joint 5a 1st joint fitting cylinder 5b cutout 5c 1st joint vertical rib 5d 1st joint collar part 6 second joint 6b valve chamber 6c ball seat 6d 2nd joint collar part 6e Second joint vertical rib 7 Ink storage tube 8 ink 9 followers 10 ball valve 11 tail plug 12 ink guide hole 13 Writing Ball 14 through holes 15 Outer cylinder

Claims (4)

[Claims] 1. A ball-point pen tip rotatably holding a writing ball at its tip, a through hole is formed at the tip, an ink containing tube is housed inside, and the ball-point pen tip projects from the through hole. A ball-point pen comprising a shaft cylinder, a resin joint that connects the ball-point pen tip and the ink containing tube, and has an ink guide hole that guides ink to the ball-point pen tip and a contact portion that contacts the tip of the shaft cylinder. The ball-point pen characterized in that the contact portions are formed at a plurality of positions in the axial direction. 2. The first joint provided on the front side in the axial direction.
And a second joint provided axially rearward, forming a valve chamber between the first joint and the second joint, and arranging a ball valve in the valve chamber, A ball receiving seat with which the ball valve can come into contact is formed on the ink guide hole of the second joint, and a contact portion is provided in each of the first joint and the second joint. The ball-point pen according to claim 1. 3. The ballpoint pen according to claim 1, wherein the contact portion is a vertical rib extending in the axial direction. 4. The ball-point pen according to claim 3, wherein the vertical rib has a tapered shape whose height decreases toward the front in the axial direction.