JPH0683384U - Ballpoint pen - Google Patents

Abstract

(57) [Summary] [Purpose] To improve the cap fitting of a ballpoint pen.
Even if there are many combinations of shaft cylinder and cap engagement parts,
The mold facilitates adjustment of the engaging part and control of molding conditions. Further, it is possible to avoid the problem of locking the cap and the front and rear of the barrel. [Structure] A ball-point pen in which a tip is projected, a base is attached to the tip of a barrel, and a tail plug is fixed to the rear end of the barrel. Engagement portions formed by ridges and groove portions and step portions with which the insertion side end portion of the cap abuts are integrally formed, and the inner hole portion of the resin cap engages with each engagement portion of the shaft cylinder. The parts are integrally formed in separate and independent positions, and the cap is detachably attachable to the front end and the rear end of the barrel while the end part and the step part are in contact with each other.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an improvement in cap fitting of a ballpoint pen.

[0002]

[Prior art]

 Conventionally, it has been publicly known that caps are detachably fitted to the front and rear of a ball-point pen barrel. As No. 1, the cap is simply fitted to the front and rear of the barrel with frictional engagement, and the fitting is too strong or too weak due to dimensional variations, which makes the fitting feel tight. poor. Further, there is a drawback that the shaft cylinder is easily scratched. 2, a fitting or an engaging portion composed of a groove and a groove is provided on the outer periphery of the mouth of the cap or the barrel, and an engaging portion for engaging with the engaging hole is provided in the inner hole of the cap to be fitted. In some cases, a tail plug is attached by friction or the like to the rear end of the shaft cylinder, and an engaging portion is provided on the outer periphery of the tail plug to fix the cap. In some cases, an engaging portion composed of a ridge and a groove is provided on the front outer periphery and the rear outer periphery of the shaft cylinder, and the engaging portions are provided on the inner holes of the caps so that they can be locked respectively. However, in the cases of 2 and 3, only one engaging portion is provided in the inner hole of the cap so that the cap can be locked to the front and rear of the barrel.

[0003]

[Problems to be solved by the device]

 The present invention is an improvement of cap fitting of a ballpoint pen, and is intended for a widely-used desk-top ballpoint pen. In order to be able to provide a large amount of this type of ballpoint pen at low cost, the barrel and cap are formed of resin molded products, and the number of molds used for molding is extremely large. Therefore, the number of combinations of the shaft cylinder and the cap to be fitted is squared, which is even more than that when considering the fitting of the cap and the shaft cylinder back and forth. It is extremely difficult to make everything uniform, and conventionally, variations have been controlled as much as possible by adjusting the mold dimensions and controlling molding conditions. An object of the present invention is to achieve the fitting of the cap and the shaft cylinder under easier conditions than ever before.

[0004]

A ball-point pen of the present invention devised to achieve the above object is a ball-point pen in which a tip is projected and a tail plug is fixed to a rear end of a shaft cylinder. Is a resin molded product, and the front and outer circumferences are integrally formed with a step portion where the engaging portion composed of a ridge and a groove and the insertion side end portion of the cap come into contact with each other, and the inner hole shaft of the resin cap is formed. The respective engaging parts of the cylinder and the engaging parts that engage with each other are integrally formed at separate and independent positions, and the cap is attached and detached with the end part and the step part contacting the front and rear of the shaft cylinder, respectively. It is characterized by being configured so that it can be freely fitted.

[0005]

【Example】

 1 to 3 show an embodiment of the present invention. First, as shown in the figure, the shaft cylinder 1 is a resin molded product, and an engaging portion 2 composed of a ridge and a groove portion is provided on the outer periphery of the front end thereof, and an end portion 14 of a cap 10 described later is provided at the rear end of the engaging portion 2. A step portion 3 that abuts is formed. Further, similarly to the above, an engaging portion 4 including a ridge and a groove portion is formed on the rear outer periphery of the shaft cylinder 1, and a step portion 5 with which the end portion 14 of the cap 10 abuts is formed at the front end of the engaging portion 4. .

In addition, the joint 8 is provided with a press-fitting cylinder portion in which a linear rib is provided at a required position in the first half, and a ring-shaped collar portion is formed at the rear end of the rib, and the rear end of the rib is The outer diameter of the collar is almost the same. Further, it has a fitting cylinder portion in the latter half thereof, and the ink containing tube 9 is fixed to the fitting cylinder portion. A tip 7 holding a tip ball is press-fitted into the tip fitting hole at the tip of the press-fitting cylinder from the rear end side.

Further, the joint 8 is integrally formed of an elastically deformable synthetic resin, and has a valve chamber provided at the rear side in communication with the tip fitting hole. A conical ball seat is provided at the rear of the valve chamber. In addition, the valve chamber is fitted in the inner circumference of the tip fitting hole, and the axis of the hole of the valve chamber is appropriately eccentric with respect to the axis of the chip fitting hole, and a groove is provided on one side of the valve chamber hole. The ball valve is loosely fitted in the valve chamber. Further, a guide hole communicating with the ball receiving seat is formed in the rear of the valve chamber.

Further, a cylindrical ink containing tube 9 is press-fitted and fixed to the outer periphery of the fitting tubular part by abutting the tip thereof to the rear end of the collar part, and the inner diameter part of the ink containing tube 9 is guided to the joint 8. It communicates with the hole. The ink containing pipe 9 is statically highly viscous, and is filled with ink having a shear thinning property that reduces the viscosity by the rotation of the tip ball during writing and allows the ink to flow out. The rear end of the ink is filled with a transparent or semi-transparent grease-like follower that prevents the evaporation of the ink and contacts the ink surface as the ink is consumed and can move following it. A pipe material having a specific gravity substantially equal to that of the follower is immersed in the follower. A tail plug 15 is fixed to the rear end of the barrel 1.

Next, from the tip of the shaft cylinder 1 to the joint 8, the tip 7 and the refill having the ink containing tube 9 filled with the ink and the follower fixed thereto are inserted, and the collar portion of the joint 8 is attached to the front surface of the shaft portion. With the rear end edge abutted, the outer periphery of the linear rib provided at the required position of the press-fitting cylinder portion is abutted against the inner step portion of the mouthpiece 6 in a biting manner, and the mouthpiece 6 of the shaft tube 1 is abutted. It is screwed onto the shaft.

By the way, in the cap 10 fitted on the tip of the shaft, the clip 13 is positioned on the outer peripheral side surface of the cap 10 and the tubular portion at the rear end is crimped to the rear end hole. In addition, a ventilation hole penetrates through the rear end of the tubular portion. A cylindrical inner cap having a small chamber is provided behind the inner hole of the cap 10, and the inner cap is integrally formed with a required number of ribs between the inner cap and the inner hole. As described above, an air passage communicating between the cap insertion port and the air hole is formed between the ribs. Further, the cap 10 has protruding engagement portions 11 and 12 formed in the inner hole portion on the insertion side at separate and independent positions. In addition, a seal stopper made of a non-absorbent, non-continuous bubble elastic body is fixed to the tip of the small chamber of the inner cap, the tip of the tip 7 and the base 6 are tightly fitted in the small chamber, and the tip ball is sealed. It is pressed into contact with the tool.

[0011]

[Action]

 As shown in FIG. 2, when the cap 10 is fitted to the tip 7 side, the engaging portion 11 elastically deforms to the engaging portion 2 with the end portion 14 of the cap abutting the step portion 3 of the barrel 1. Positioned and locked by. As shown in FIG. 1, when the cap 10 is fitted to the tail plug 15 side, the engaging portion 12 is elastic to the engaging portion 4 with the end portion 14 of the cap abutting the step portion 5 of the barrel 1. It is positioned and locked by deformation. That is, since the step portions are formed on the front and rear outer peripheries of the barrel 1 together with the engaging portions, the separate engaging portions 11 and 12 of the cap 10 are reliably classified into the engaging portions of the respective barrels. It can be locked.

[0012]

[Effect of device]

 The structure and operation of the ball-point pen of the present invention are as described above. By forming separate and independent engaging portions in the inner hole of the cap, extremely many combinations of fitting adjustment separate the front and rear of the barrel. This makes it possible to reduce mold size adjustment and control of molding conditions. Further, unlike the conventional case, the engaging portion at one place of the cap does not engage at the two places of the barrel, so that even if there is a gap between the dimensions of the engaging portions at the two places of the barrel, This has the effect of preventing a problem in locking the shaft cylinder (correcting one fitting side to be stronger and loosening the other side).

[Brief description of drawings]

FIG. 1 is a half cross-sectional view of a ball-point pen that is an embodiment of the present invention, showing a state in which a cap is fitted behind a barrel.

FIG. 2 is an enlarged cross-sectional view of a front half of a ball-point pen that is an embodiment of the present invention, showing a state in which a cap is fitted to the tip of a barrel.

FIG. 3 is an enlarged cross-sectional view of the rear half of the ball-point pen that is an embodiment of the present invention.

[Explanation of symbols]

 1 Shaft Cylinder 2 Engagement Part 3 Step Part 4 Engagement Part 5 Step Part 6 Base 7 Chip 8 Joint 9 Ink Storage Tube 10 Cap 11 Engagement Part 12 Engagement Part 13 Clip 14 End Part 15 Tail Plug

Claims (1)

[Scope of utility model registration request] 1. A ball-point pen having a tip attached to a tip of a barrel and a tail plug fixed to a rear end of the barrel, wherein the barrel is a resin molded product, and its outer periphery and rear side. An engaging portion formed by a ridge and a groove portion and a step portion with which the insertion side end portion of the cap abuts are integrally formed on the outer periphery, respectively, and are engaged with the engaging portions of the shaft cylinder in the inner hole portion of the resin cap. The engaging portions are integrally formed separately at independent positions, and the cap is configured to be detachably fitted to the front and rear of the barrel with the end portion and the step portion in contact with each other. A ball-point pen characterized by that.