JPH0733681U - Ballpoint pen - Google Patents

Abstract

(57) [Summary] [Purpose] It is possible to easily display the color of ink in a ball-point pen, prevent backflow of ink, and prevent rattling of the tip. [Structure] A ball-point pen refill equipped with an ink backflow prevention mechanism in which a tip of a ballpoint pen is pressure-bonded to the joint end, an ink storage tube is fixed to the rear end, and a ball valve is loosely fitted in the inner hole of the joint. It is a ball-point pen that is mounted inside and positioned so that the tip of the tip protrudes.A step is provided in the inner hole of the mouth part that is integrally provided at the tip of the barrel, and an inclined rib is provided on the outer periphery of the tip of the joint. The rib is provided so as to engage with the step portion of the tip of the mouth in a biting manner to prevent the chip from rattling. Further, the shaft cylinder is made of a transparent resin, and the joint is made of a resin having the same color as the ink color so that the ink color can be seen at a glance.

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, an ink backflow prevention mechanism for a ballpoint pen is disclosed in Japanese Utility Model Publication No. 4-52067. Further, a ballpoint pen refill is usually constructed by fixing a tip of a ballpoint pen to the tip of a tube-shaped ink containing tube, and providing a rib having a stepped portion at a plurality of points in an inner hole of a tip end of a shaft cylinder, It is known that the tip of the ink containing tube comes into contact with the step portion when the tip is in a protruding state by mounting a ball-point pen refill on the shaft cylinder to prevent backlash of the chip. It is well known that the barrel is made of transparent resin.

[0003]

[Problems to be solved by the device]

 The present invention is directed to a widely-used desk-top ballpoint pen. This type of ball-point pen is consumed in large quantities for office work, and there are high demands for economy and quality. As a request, 1. Know ink consumption. 2. The color display of the ink is easy to understand. 3. Do not let ink flow backwards until it is used up, and it will not become dirty or unreadable. 4. The tip should not rattle when writing. And so on. The present invention is particularly applicable to the above 2. And 3. And 4. Is an improvement.

[0004]

[Means for Solving the Problems]

 The ballpoint pen of the present invention devised to achieve the above object is such that the tip of the ball-point pen is crimped to the tip of the joint, the ink storage tube is fixed to the rear end, and the ball valve is attached to the inner hole of the joint. In a ballpoint pen in which a ballpoint pen refill equipped with an ink backflow prevention mechanism that loosely fits is mounted in the barrel and positioned so that the tip of the tip projects, an inner hole at the tip of the barrel that is integrally provided at the tip of the barrel A step is provided on the tip of the joint, and a tilted rib is provided at a desired position on the outer periphery of the tip of the joint, and the rib is engaged with the step of the inner hole in a biting manner to prevent backlash of the tip. At the same time, the joint is made of a resin of the same color as the ink color, and the barrel is made of a transparent resin.

[0005]

【Example】

 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 part 3 integrally at its tip, an engaging part consisting of a protrusion and a groove part on its outer periphery, and a step part in the inner hole. 3'is formed. Further, a step portion is formed at the rear end of the engaging portion, with which the end portion of the cap 24 described later comes into contact. Further, a tail plug 21 is detachably fixed to the rear of the barrel 1 and the outer periphery of the tail plug 21 has an engaging portion composed of a protrusion and a groove portion as described above and a cap 24 at the front end of the engaging portion. Is formed with a step portion with which the end portion of the contact portion abuts.

In addition, the joint 4 is provided with a front shaft portion 5 in which an inclined rib 12 is formed at a required position in a front half thereof, and a ring-shaped collar portion 6 is formed at a rear end of the rib to form the rib 12. The rear end of the collar 6 is connected to the outer diameter of the collar 6 to be substantially the same. 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. The tip 14 holding the tip ball 15 is press-fitted into the tip hole of the front shaft portion 5 from the rear end side.

The joint 4 is integrally formed of a synthetic resin that is the same color as the ink color and is elastically deformable, and a valve chamber 8 is provided at the rear of the joint 4 so as to communicate 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 fits inside the inner periphery of the tip hole, and the axis of the hole of the valve chamber 8 is appropriately eccentric with respect to the tip hole, that is, the axis of the press-fitting shaft portion of the tip, and at the same time, one side of the valve chamber hole A groove portion 9 is provided in the valve chamber, and a ball valve 13 is loosely fitted in the valve chamber. Further, a guide hole 11 that communicates with the ball receiving seat 10 is formed behind the valve chamber 8.

A cylindrical ink storage tube 18 is press-fitted and fixed to the outer periphery of the rear shaft portion 7 by abutting the tip thereof to the rear end of the collar portion 6, and the inner diameter portion of the ink storage tube 18 is guided to the joint 4. It communicates with the hole 11. The ink containing tube 18 is filled with the ink 19 having a statically high viscosity and a shear thinning property that reduces the viscosity by the rotation of the tip ball during writing and allows the ink to flow out. Further, the rear end of the ink 19 is filled with a transparent or semi-transparent grease-like follower 20 which prevents the evaporation of the ink and is movable in contact with the ink surface as the ink is consumed. A pipe material 20 'having a specific gravity substantially equal to that of the follower 20 is immersed in the follower 20. A tail plug 21 is detachably attached to the rear end of the barrel 1.

Next, the ballpoint pen refill 2 to which the tip 14, the ink 19, and the ink containing tube 18 filled with the follower 20 are fixed is inserted into the joint 4 from the tip of the barrel 1 and the tip portion 3 of the barrel 3 is inserted. The rear end of the ink containing tube 18 is fitted into the inner hole of the tail plug 21 with the outer periphery of the inclined rib 12 provided at a required position of the front shaft portion 5 of the joint on the stepped portion 3'butting against each other in a biting manner. The tail plug 21 is fixed to the rear end of the barrel 1 so as to come into contact with the stepped portion 23 of the rib 22 provided at the required position.

By the way, the cap 24 fitted on the shaft tip is a transparent resin molded product having excellent elasticity, and a clip is positioned on the outer peripheral side surface of the cap 24 to crimp the rear end cylindrical portion to the rear end hole. Further, a ventilation hole penetrates through the rear end of the tubular portion. A cylindrical inner cap 25 having a small chamber is provided behind the inner hole of the cap 24, and the inner cap 25 is integrally formed with a required number of ribs between the inner cap 25 and the inner hole portion. As described above, a ventilation path communicating with the ventilation hole from the cap insertion opening is formed between the ribs. Further, the cap 24 is formed with two engaging portions of protrusions at two separate and independent positions in the inner hole portion on the insertion side. Further, a seal stopper 26 made of a non-liquid absorbing and non-continuous bubble elastic body is fixed to the tip of the small chamber of the inner cap 25, and the tip 14 and the tip of the mouth portion 3 are closely fitted in the small chamber. The tip ball 15 is appropriately pressed against the seal plug 26.

[0011]

[Action]

 With the above configuration, backflow of ink is prevented against upward writing and impact. Further, since the rib 12 of the joint is engaged with the step portion 3 "of the tip portion 3 in a biting manner, the rattling of the tip 14 is prevented. Further, since the mouth portion 3 is transparent, the joint 4 can be seen through.

[0012]

[Effect of device]

 The structure and operation of the ball-point pen of the present invention are as described above, and since backflow of ink can be prevented, inability to write and stain are prevented. Since the joint is the same color as the ink color, the type of ink is clear. In addition, there is no rattling of the tip, so the writing feel is good.

[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 a rear half portion of a 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 behind a barrel.

[Explanation of symbols]

 1 Shaft cylinder 2 Ballpoint 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 press ball 16 Press fit Shaft part 17 Rear end part 18 Ink storage tube 19 Ink 20 Follower 20 'Pipe material 21 Tail plug 22 Rib 23 Step part 24 Cap 25 Inner cap 26 Seal plug body

Claims (1)

[Scope of utility model registration request] 1. A ball-point pen refill equipped with an ink backflow prevention mechanism in which a tip of a ballpoint pen is pressure-bonded to the tip of a joint, an ink containing tube is fixed to the rear end, and a ball valve is loosely fitted in an inner hole of the joint. In a ball-point pen that is mounted inside the shaft cylinder and positioned so that the tip of the tip projects, a step is provided in the inner hole of the mouth part that is integrally provided at the tip of the shaft cylinder, and a sloped shape is formed at the outer peripheral part of the joint ahead. The rib is provided at a required position, and the rib is engaged with the stepped portion of the inner hole in a biting manner to prevent rattling of the tip, and the joint is made of resin of the same color as the ink A ballpoint pen that is made of a transparent resin.