JPH0939471A - Ball-point pen - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid danger such as suffocation even if a cap and a tail plug are deteched from the shaft cylinder of a ball-point pen to be swallowed. SOLUTION: In a ball-point pen wherein the refill 2 of the ball-point pen is charged in a shaft cylinder and the leading end of a tip 14 is positioned so as to be protruded from the leading end port of the shaft cylinder by the tail plug fixed to the rear end of the shaft cylinder in contact with the rear end of the refill 2, a venting hole 26 enabling air to pass is bored in the rear end of the tail plug and an air passage venting air from an insertion port to a rear end is provided to the cap 20 provided to the leading end of the shaft cylinder.

Description

Detailed Description of the Invention

[0001]

This invention relates to the safety of ballpoint pens.

[0002]

2. Description of the Related Art Although it is extremely rare, since infants swallow their caps and suffocate, a means has been taken to allow air circulation even when swallowed by a cap of a writing instrument.

[0003]

DISCLOSURE OF THE INVENTION The present invention is directed to a widely-used desk-top ballpoint pen. This type of ballpoint pen is consumed in large quantities, and there is a high chance that infants will unfortunately swallow it. Therefore, it is an object of the present invention to provide a highly safe ballpoint pen by equipping the removable small parts with air circulation means.

[0004]

[MEANS FOR SOLVING THE PROBLEMS] A ball-point pen refill is mounted in a barrel, and a tip plug is fixed to the rear end of the barrel by contacting the rear end of the ball-point refill so that the tip of the tip comes out from the tip opening of the barrel. In a ball-point pen positioned so as to project, a vent hole through which air can flow is formed in the rear end of the tail plug, and a cap attached to the front of the barrel is pulled out from the insertion opening to the rear end. An air flow passage is provided.

[0005]

1 to 3 show an embodiment of the present invention. First, as shown in the figure, the shaft cylinder 1 is a transparent resin molded product, and has a mouth end portion 3 integrally at its tip, an engaging portion composed of a protrusion and a groove portion on the outer periphery thereof, and a step portion at the inner hole. 3'is formed. Further, a step portion with which the end portion of the cap 20 abuts is formed at the rear end of the engaging portion.

The joint 4 has ribs 12 inclined in the first half.
Is formed at a required position, a ring-shaped collar portion 6 is formed at the rear end of the rib, and the rear end of the rib 12 is connected to the outer diameter of the collar portion 6 to be substantially the same. ing. Further, the rear shaft portion 7 is provided in the latter half, and the ink containing tube 18 is fixed to the rear shaft portion 7. Further, the tip ball 15 is provided in the tip hole of the front shaft portion 5.
The chip 14 holding the is pressed in from the rear end side.

Further, the joint 4 is integrally formed of an elastically deformable synthetic resin of the same color as the ink color, and a valve chamber 8 is provided at the rear side in communication with the tip hole of the front shaft portion 5.
A conical ball receiving seat 10 is provided at the rear of the valve chamber 8. Further, the valve chamber 8 is accommodated in the inner circumference of the tip hole,
The axial center of the hole of the valve chamber 8 is appropriately eccentric with respect to the distal end hole, that is, the axial center of the press-fitting shaft portion of the tip, and the groove portion 9 is provided on one side of the valve chamber hole, and the ball valve 13 is loosely fitted in the valve chamber. To be done. or,
Behind the valve chamber 8 is a guide hole 11 communicating with the ball receiving seat 10.
Are formed.

On the outer periphery of the rear shaft portion 7, a cylindrical ink accommodating tube 18 is press-fitted and fixed by abutting its tip against the rear end of the collar portion 6, and the inner diameter portion of the ink accommodating tube 18 is guided to the joint 4. It communicates with the hole 11. Ink 19 having a high viscosity statically in the ink containing tube 18 and a shear thinning viscosity that allows the ink to flow out due to a decrease in viscosity due to the rotation of the tip ball during writing.
Further, the rear end of the ink 19 is filled with a transparent or semi-transparent grease-like follower 27 which prevents the evaporation of the ink and is movable in contact with the ink surface as the ink is consumed. There is. A pipe-shaped follower rod 28 having a specific gravity substantially equal to that of the follower is immersed in the follower 27. The follower stick may be solid. A tail plug 29 is detachably attached to the rear end of the barrel 1.

Next, from the rear end of the barrel 1, the ballpoint pen refill 2 to which the tip 14, the ink 19, and the ink containing tube 18 filled with the follower 27 are fixed is inserted from the rear end of the barrel 4 into the tip portion 3 of the barrel. The front shaft 5 of the joint on the step 3 '
In the state where the outer periphery of the inclined rib 12 provided at the required position is butted against each other, the rear end of the ink containing tube 18 is provided in the inner hole of the tail plug 29 at the required portion 31 of the rib 30. The tail plug 29 is screwed and fixed to the rear end of the barrel 1 so as to abut. The tail plug 29 has an outer periphery formed with an engagement portion including a protrusion and a groove portion, and a step portion with which the end portion of the cap 20 abuts on the front end of the engagement portion.

By the way, the cap 20 attached to the tip of the shaft
Is a transparent resin molded product having excellent elasticity, and the clip 24 is positioned on the outer peripheral side surface of the molded product to press the rear end tubular portion 25 into the cap rear end hole. Further, a ventilation hole 26 penetrates the rear end of the tubular portion 25. Further, a cylindrical inner cap 21 having a small chamber is formed behind the inner hole of the cap 20, and the inner cap 21 is integrally connected by a required number of ribs 22 provided between the outer wall of the inner cap 21 and the inner wall of the cap. From the above,
Vent hole 2 from the cap insertion port through between the ribs
An air flow passage communicating with 6 is formed. Also, the cap 2
In No. 0, the engaging portions of the protrusions are formed at two separate and independent positions in the inner hole portion on the insertion side. Further, a seal plug 23 made of a non-absorbent and non-continuous bubble elastic body is fixed to the tip of the small chamber of the inner cap 21, and the tip of the tip 14 and the mouth end portion 3 are fitted closely in the small chamber. Tip ball 1
5 is pressed against the seal plug 23 as appropriate.

[0011]

With the above configuration, the cap 20 and the tail plug 29
Even if is disengaged from the shaft cylinder and is swallowed, an air flow passage is secured.

[0012]

The structure and operation of the ball-point pen of the present invention are as described above, and it is possible to avoid the risk of suffocation even if there is an accident of swallowing.

[Brief description of drawings]

FIG. 1 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. 2 is an enlarged cross-sectional view of the rear half of the ball-point pen that is an embodiment of the present invention.

FIG. 3 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 on the tail plug side of a barrel.

[Explanation of symbols]

 1 shaft cylinder 2 ball-point pen refill 3 tip part 3 `step part 4 joint 5 front shaft part 6 collar part 7 rear shaft part 8 valve chamber 9 groove part 10 ball receiving seat 11 guide hole 12 rib 13 ball valve 14 tip 15 tip ball 16 press fitting Shaft 17 Rear end 18 Ink storage tube 19 Ink 20 Cap 21 Inner cap 22 Rib 23 Seal plug 24 Clip 25 Tube 26 Vent hole 27 Follower 28 Follower rod 29 Tail plug 30 Rib 31 Step 32 Vent

Claims (4)

[Claims] 1. A ball-point pen refill is mounted in a barrel, and a tip end of the tip is projected from a tip port of the barrel by a tail plug abutting against the rear end of the ball-pen refill and fixed to the rear end of the barrel. In the positioned ballpoint pen,
A ball-point pen having a hole through which air can flow in the rear end of the tail plug. 2. A rib having a stepped portion is formed at a required position on the inner wall of the tail plug, and a vent hole is formed at a rear end of the tail plug in communication with a gap formed between the rib and the rib. 2. The ball-point pen according to claim 1, wherein the rear end of the ball-point pen refill is in contact with the step portion and the tail plug is fixed to the rear end of the barrel. 3. The ball-point pen according to claim 1, wherein the cap attached to the front side of the shaft cylinder is provided with an air flow passage extending from the insertion port to the rear end. 4. The cap attached to the tip of the shaft is formed integrally with an inner cap for tightly fitting the writing tip portion in a small chamber, and a rib is formed at a required position between the inner wall of the cap and the outer wall of the inner cap. Then, a ventilation hole is provided from the insertion side of the cap to the rear end through the gap between the ribs, and the tip of the tip is pressed against the inside of the inner cap. 4. The ball-point pen according to claim 3, wherein a seal plug having the seal plug is provided.