JP2557073Y2 - Ballpoint pen - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION The present invention uses ink having a so-called shear thinning viscosity, which has a high viscosity in a static state, and the viscosity is reduced by rotation of a ball at the time of writing so that the ink flows out. Regarding improvement of ballpoint pens.

[0002]

2. Description of the Related Art Heretofore, there has been known a so-called water-based ballpoint pen in which ink is incorporated in a so-called oil-based ballpoint pen using high-viscosity ink and a fibrous batting, and the ink is guided to a ballpoint pen tip via an ink guide core. ing. Each of them has some drawbacks, but one of the shortcomings is that oil-based ballpoint pens have a disadvantage in that the ink has a high viscosity, and thus the ink has a low writing density and a low writing density. Further, the water-based ball-point pen has disadvantages in that the use of the batting containing the ink increases the cost of members and increases the cost, and that the consumption of the ink is unknown. In addition, under such circumstances, for the purpose of improving each of the drawbacks, the ink having a high viscosity is statically reduced, and the viscosity is reduced by the rotation of the ball at the time of writing, so that the ink having the shear thinning viscosity is discharged. The ballpoint pen used is also known. However, ballpoint pens that use ink with shear thinning have a tendency to evaporate the ink and have a large amount of ink flowing out (to increase the writing density) by increasing the diameter of the ink storage tube to increase the amount of ink loaded. Have many. Further, since the viscosity of the ink is smaller than that of the ink of the oil-based ball-point pen, the flow resistance to the ink storage tube is small. Therefore, ink leakage (ink flows backward at the rear end of the ink storage tube) easily occurs due to a change in atmospheric pressure or temperature. For this reason, the ink is usually prevented from evaporating at the rear end of the ink and moves following the consumption of ink during writing, but a grease-like shape that suppresses the backflow of the ink against changes in atmospheric pressure and temperature Follower is provided. However, even when the follower is provided, when ink is written immediately below the tip ball when writing upwards, the ink head is added directly, causing a remarkable backflow, thereby contaminating the inside of the barrel and vent holes provided in the barrel. There is a danger of ink leaking from and soiling hands and clothes. The situation is not the ratio of the situation that occurs with oil-based ballpoint pens.

[0003]

The object of the present invention is to use an ink which has a high viscosity in a static state, and has a shear thinning viscosity in which the viscosity is reduced by rotation of a ball at the time of writing and the ink flows out. This is an improvement of the ballpoint pen described above, which can prevent the ink from flowing backward even when the atmospheric pressure and the temperature change and when writing upward, so that the inside of the shaft cylinder, hands and clothes can be prevented from being stained.

[0004]

The ballpoint pen according to the present invention, which has been devised to achieve the above object, has a tip fixed to the tip of a barrel, and an ink storage tube communicating with the tip is provided in the barrel. At the same time, the ink storage tube has a statically high viscosity, and the viscosity of the ink decreases when the ball rotates during writing. Is provided with a follower that can move following the prevention of ink evaporation and ink depletion, and a joint that fixes the chip is made of a resin molded product that can be elastically deformed. Or a tail plug made of an elastically deformable resin molded product is tightly fixed to the rear end of the barrel or the rear end of the ink storage tube, and is opposed to the follower of the ink storage tube in front of the tail plug. A valve chamber is provided at the rear of the valve chamber. In addition, the front inner surface has an axial ridge, and a shaft-shaped top having a tapered portion between which it can be in close contact with the frame receiving seat is provided so as to be non-extractably loosely fitted. I do.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention shown in FIGS. 1 and 2 has a locking cylinder 7 in the first half and a fitting cylinder 13 in the second half. An axial slit 8 is provided at a required position on the circumference, and a joint 3 is provided which is capable of elastically deforming the front end in a diameter reducing direction. In the inner hole of the locking cylinder portion 7, a tip fitting hole 12 and a holding portion 1 having substantially the same outer diameter as the tip 5 from the rear end.
1 and a gap 10 having an inner diameter appropriately larger than the outer diameter of the tip 5 is formed at the end thereof.
Are press-fitted from the rear end side.

The joint 3 is made of an elastically deformable synthetic resin and is integrally formed. A valve chamber 14 is provided at the rear in communication with the chip fitting hole 12. A tapered frame receiving seat 15 is provided at a rear portion of the valve chamber 14, and an axially projecting ridge is provided on an inner surface of the front portion so that a diameter of a virtual inscribed circle is smaller than a shaft diameter of a frame 19 described later. 16 are provided at a plurality of positions on the circumference, and a shaft-shaped top 19 having a tapered portion 20 at the rear portion between the frame receiving seat 15 and the ridge 16 is provided with a ridge 16.
The ridge 16 is inserted while being elastically deformed from the direction of FIG. A guide hole 18 communicating with the frame receiving seat 15 is formed behind the valve chamber 14. still,
The ink penetrates a gap formed between the inner circumference of the valve chamber 14 and the outer circumference of the top 19, but if necessary, the outer circumference of the top 19 is formed with a groove except for the tapered portion 20 for ink communication. Are provided.

A flange 17 is provided at the rear end of the engaging cylinder 7 of the joint 3, and a fitting cylinder 13 is provided behind the flange 17.
Is extended. A cylindrical ink storage tube 4 is press-fitted and fixed to the outer periphery of the fitting cylindrical portion 13 with its front end abutting on the rear end of the flange portion 17.
8 is connected. The ink container 4 is filled with an ink 22 having a statically high viscosity, a shear-thinning viscosity that allows the ink to flow out by rotating the ball at the time of writing so that the ink can flow out. The rear end is filled with a grease-like follower 23 which prevents evaporation of the ink and can move following the ink surface as the ink is consumed. The ink storage tube 4 is made of, for example, a transparent PP resin molded product that suppresses evaporation of ink.

Next, a writing portion, to which the chip 5 and the ink containing tube 4 filled with ink are fixed, is inserted into the joint 3 from the tip of the barrel 1, and the flange 17 of the joint 3 is inserted into the front surface of the shaft portion 6. The base 2 having the tapered portion 9 provided on the inner surface by abutting the edges.
Is screwed to the shaft portion 6 of the shaft cylinder 1 in a state where the tapered portion 9 is brought into contact with the front end edge of the locking tube portion 7 of the joint 3. Further, a ventilation hole 21 communicating with the inner hole of the barrel is formed at an appropriate position of the barrel 1, and a tail plug 24 is press-fitted and fixed to the rear end of the barrel 1. Note that a transparent resin molded product is used for the barrel 1 so that the amount of ink consumption can be determined.

In the second embodiment of the present invention shown in FIGS. 3 and 4, a locking cylinder 7 # is provided in the first half and a fitting cylinder 13 # is provided in the second half. Is provided with a joint 3 # provided with an axial slit 8 # at a required position on the circumference and capable of elastically deforming the front end in the radial direction. The inner hole of the locking cylinder 7 # has a tip fitting hole 12 # from the rear end, a holding portion 11 # substantially the same as the outer diameter of the chip 5, and a gap having an inner diameter appropriately larger than the outer diameter of the tip 5 at the tip. The tip 5 is press-fitted from the rear end side into the inner hole of the locking cylinder portion 7 #.

The joint 3 # is integrally formed of an elastically deformable synthetic resin, and has the tip fitting hole 12 #.
And a guide hole 14 # is provided at the rear in communication therewith. A flange 16 # is provided at the rear end of the engagement cylinder 7 # of the joint 3 #, and a fitting cylinder 13 # extends behind the flange 16 #. A cylindrical ink storage tube 4 is press-fitted and fixed to the outer periphery of the fitting cylindrical portion 13 # by abutting its front end against the rear end of the flange 16 #, and the inside diameter of the ink storage tube 4 is formed as a guide hole of the joint 3 #. 14
It is in communication with. The ink container 4 is filled with an ink 22 having a high viscosity statically, and having a shear-thinning viscosity so that the viscosity can be reduced by the rotation of the ball during writing and the ink can flow out. The rear end is filled with a grease-like follower 23 which prevents evaporation of the ink and is movable in contact with the ink surface as the ink is consumed. The ink storage tube 4 is made of, for example, a transparent PP resin molded product that suppresses evaporation of ink.

Next, a writing portion to which the tip 5 and the ink containing tube 4 filled with ink are fixed is inserted into the joint 3 か ら from the tip of the barrel 1, and a flange 16 of the joint 3 に is inserted into the front surface of the shaft portion 6. ｀
The base 2 provided with a tapered portion 9 on the inner surface thereof is brought into contact with the rear end edge thereof, and the tapered portion 9 is connected to the locking cylindrical portion 7 of the joint 3 ｀.
The screw is screwed to the shaft portion 6 of the shaft cylinder 1 in a state where the front end of the shaft is abutted against the shaft. Further, a ventilation hole 21 communicating with the inner hole of the barrel is formed at an appropriate position of the barrel 1, and a tail plug 2 is provided at the rear end of the barrel 1.
5 is press-fitted and fixed. Note that a transparent resin molded product is used for the barrel 1 so that the amount of ink consumption can be determined.

The tail plug 25 is made of an elastically deformable synthetic resin and is integrally formed. The tail plug 25 is press-fitted and fixed to the rear end hole of the barrel 1 in a substantially close fit manner. 4 is closely fitted in the inner hole of the rear end. Also, tail plug 2
5 has a valve chamber 26 at the front end thereof, a tapered frame receiving seat 28 at the rear of the valve chamber 26, and the diameter of the imaginary inscribed circle on the inner surface of the front is the shaft diameter of the frame 30. The protrusions 27 in the axial direction are provided at a plurality of positions on the circumference so as to be smaller than the top, and the top 30 having the tapered portion 31 at the rear portion between the frame receiving seat 28 and the protrusion 27 is Ridge 27 from the direction
Is elastically deformed and inserted into the valve chamber 26 to loosely fit. Further, a vent hole 29 communicating with the frame receiving seat 28 is provided to the rear end of the tail plug 25 behind the valve chamber 26.

FIG. 5 shows a third embodiment of the present invention. The difference from the second embodiment is that a tail plug 25 mm is provided.
Is closely fitted to the rear end hole of the ink storage tube 4. Also in this case, a valve chamber 26 # is provided at the front end of the tail plug 25 # facing the rear end of the follower 23, and the frame receiving seat 28 # and the ridge 27 are provided.
A shaft-like top 30 # having a ｀ and a tapered portion 31 # at the rear is loosely fitted in the valve chamber 26 #. In addition, a ventilation hole 29 至 る extending to the rear end of the tail plug 25 後方 behind the frame receiving seat 28 ｀.
Is provided, and a rear end of the barrel 1 # is closed, and a second ventilation hole 2 communicating with an inner hole of a predetermined side surface of the barrel 1 # is provided.
1 ｀ is provided.

[0014]

First, in the first embodiment, FIG. 1 shows a writing state in which the tip 5 is turned downward.
4 comes into contact with the ridges 16 of the ink cartridge 4, and the ink 22 that has entered the valve chamber 14 from the ink storage tube 4 through the guide hole 18 is
9, it is guided to the tip of the tip 5 after passing between the ridges 16. Although the ink has a statically high viscosity, the viscosity decreases due to the rotation of the ball at the tip of the chip 5, and a large amount of the ink flows out. FIG. 2 shows a state where the chip 5 is directed upward, and at this time, the tapered portion 20 of the top 19 is
Since it is located at the frame receiving seat 15 and seals the guide hole 18,
Even if the ink is written upward and the ink immediately below the ball of the chip runs out, the ink is caught by the head and does not flow backward. Further, in the present invention, since the front end edge of the upper locking cylinder 7 press-fitted into the chip fitting hole 12 of the locking cylinder 7 of the joint 3 abuts against the inner tapered portion 9 of the base 2, the locking is performed. An external force in the radial direction (diameter decreasing direction) toward the axis acts on the tip of the cylindrical portion 7 by the tapered portion 9, and the clamping force of the chip 5 located inside the cylindrical portion 7 is increased by the holding portion 11. Further, the tip of the locking cylinder 7 is appropriately reduced in diameter by the tapered portion 9 by the gap 10, and the tip 5 is loosened between the tip 5 and the base 2.

FIG. 3 shows a writing state in which the tip 5 is directed downward in the second embodiment. At this time, the top 30 of the tail plug 25 comes into contact with the ridge 27 of the valve chamber 26, and Since the outside air communicates with the rear end of the ink storage tube 4 through the vent hole 29 of the stopper 25, the ink 22 is guided from the ink storage tube 4 to the tip of the chip 5 through the guide hole 14 '. Although the ink has a statically high viscosity, the viscosity decreases due to the rotation of the ball at the tip of the chip 5, and a large amount of the ink flows out. FIG. 4 shows a state in which the chip 5 is turned upward, and at this time, the frame 30
Since the tapered portion 31 is located at the frame receiving seat 28 of the valve chamber 26 and seals the ventilation hole 29, the ink is written upward, the ink immediately below the ball of the chip is exhausted, the head is engaged, and the follower 23 is retracted together with the ink 22. At this time, the air in the space between the follower 23 and the valve chamber 26 is compressed, and further retreat of the follower 23 is suppressed. Therefore, the backflow of the ink is prevented. Also, in the case of FIG. 5 showing the third embodiment, the operation is exactly the same, and the description thereof will be omitted. Also, in the second embodiment, the tip 5 is pressed into the tip fitting hole 12 # of the locking cylinder 7 # of the joint 3 #, and the front end edge of the locking cylinder 7 # is tapered to the inner surface of the base 2. Because it abuts against the part 9, the locking cylinder part 7 ｀
An external force in the radial direction (diameter reduction direction) toward the axis acts on the tip of the tip 5, and the clamping force of the chip 5 located inside the tip 5 increases due to the holding portion 11 ｀. Further, the tip of the locking cylindrical portion 7 # is appropriately reduced in diameter by the tapered portion 9 due to the gap 10 #, and the tip 5 is prevented from rattling with the base 2.

[0016]

The configuration and operation of the ballpoint pen according to the present invention are as described above. A valve chamber is provided in a fitting or a tail plug closely fitted to the rear end of a shaft cylinder or the rear end of an ink storage tube. It is possible to prevent an accident in which the ink flows backward in the upward writing by the fitted frame and stains the inside of the shaft cylinder, hands, clothes, and the like. Further, since the fixing force of the press-fitting portion of the tip and the joint is strengthened, even if the fitting is loosened slightly, there is no danger of ink leakage or chip detachment. This also guarantees that the reduction in dimensional accuracy leads to a reduction in the number of processes and a reduction in the rejection rate, thereby enabling cost reductions and a high-pressure state in which the press-fitting state of the chip has been stabilized for a long time. This provides the effect of providing a quality product and the effect of providing a good brush feel because the tip and the base are rattled.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a main part of a ballpoint pen according to a first embodiment of the present invention, showing a state in which a chip is directed downward.

FIG. 2 is a longitudinal sectional view of a main part of the ballpoint pen according to the first embodiment of the present invention, showing a state in which a chip is directed upward;

FIG. 3 is a vertical sectional view of a main part of a ballpoint pen according to a second embodiment of the present invention, showing a state in which a chip is directed downward.

FIG. 4 is a vertical sectional view of a main part of a ballpoint pen according to a second embodiment of the present invention, showing a state in which a chip is directed upward;

FIG. 5 is a sectional view of a main part according to a third embodiment of the present invention;
This shows a state where the chip is turned upward.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Shaft cylinder 1 ｀ Shaft cylinder 2 Cap 3 Joint 3 ｀ Joint 4 Ink storage tube 5 Tip 6 Shaft 7 Locking cylinder 7 Locking cylinder 8 Slit 8 Slit 9 Tapered part 10 Gap 10 Gap 11 Holding part 11 ｀ Nipping portion 12 Chip fitting hole 12 ｀ Chip fitting hole 13 Fitting tube portion 13 ｀ Fitting tube portion 14 Valve chamber 14 ｀ Guide hole 15 Frame receiving seat 16 Protrusion 16 ｀ Flange portion 17 Flange portion 18 Guide hole 19 frame 20 taper portion 21 vent hole 21 ｀ vent hole 22 ink 23 follower 24 tail plug 25 tail plug 25 ｀ tail plug 26 valve room 26 ｀ valve room 27 ridge 27 ｀ ridge 28 frame receiver 28 ｀ frame receiver 29 Vent hole 29 ｀ Vent hole 30 top 30 ｀ top 31 Tapered section 31 ｀ Tapered section

Claims (1)

(57) [Scope of request for utility model registration] 1. A tip is fixed to a tip of a barrel, and an ink storage tube communicating with the tip is disposed in the barrel.
The ink storage tube has a statically high viscosity, and the viscosity of the ink decreases due to the rotation of the ball during writing, so that the ink flows out. Provide a follower that can move following the consumption of ink together with the prevention of evaporation, and a joint that fixes the chip is made of an elastically deformable resin molded product, and is provided with a valve chamber at the rear in communication with the rear end of the chip. A tail plug made of an elastically deformable resin molded product is tightly fitted to the rear end of the barrel or the rear end of the ink storage tube, and is opposed to the follower of the ink storage tube in front of the tail plug. Is provided with a tapered frame receiving seat at the rear part of the valve chamber, and a tapered part having an axial ridge on the inner surface of the front part and having a tapered part between which it can be in close contact with the frame receiving seat. A ballpoint pen characterized in that a top piece is loosely fitted so as not to be pulled out.