JPH11301172A - Ball-point pen - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ball-point pen which has an appearance having favorable portability and using handiness, and in which a water-color ink of an intermediate viscosity, or an oil-based ink of a low viscosity is filled. SOLUTION: For this ball-point pen wherein two ball-point pen refills 3a, 3b are loaded in a barrel cylinder 1 so that respective tip ends of tips may be projected from mouth tip parts 2a, 2b at both ends of the barrel cylinder 1, an ink housing tube 13 of the refills 3a, 3b is formed in such a manner that a small diameter part 15 is formed at the leading part of the tip, and behind the small diameter part 15, large diameter parts 14a, 14b where an ink is filled, are formed and a cross sectional shape for which the large diameter parts 14a, 14b of the two refills 3a, 3b are joined is placed under a state wherein the cross sectional shape is approx. bought into contact with the inside of an approx. oval shaped cross sectional shape of the inner periphery of the barrel cylinder 1, and in an ink housing tube 13, water-color ball-point pen ink having a so-called shear viscosity reducing, or an oil-based ink of a low viscosity, which flows out due to the reduction of the viscosity by the rotation of a leading end ball 9 accompanying a wring, is filled, and at the rear end of the ink, a follower 24 comprising a grease-form semi-transparent non-drying substance, which moves following the consumption of the ink accompanying a writing, is filled.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double-headed ball-point pen provided with tip ends protruding from both ends of a shaft cylinder.

[0002]

2. Description of the Related Art In general, there is known a double-type writing instrument in which a plurality of refills of a small-diameter oil-based ballpoint pen are mounted so that the tip of the tip can be selectively protruded and retracted from an axis. There is also known a ball-point pen in which two small-diameter refills of oil-based ball-point pens are mounted in the shaft cylinder such that tips of the tips protrude from the mouth portions at both ends of the shaft cylinder.

Conventionally known oil-based ballpoint pens have high resistance to the rotation of the ball when the ink flows out of the pen tip because the ink used for it has a high viscosity of several thousand mPa · S or more. Therefore, there is a drawback that writing is bad.
In addition, there is a problem in that the amount of ink flowing out from the tip during writing is small, there is a dent phenomenon, the writing line is uneven, the writing density is low, and a high writing pressure is required. As an improvement of the oil-based ball-point pen, recently, a ball-point pen for water-based ink called medium viscosity using an ink having the above-mentioned intermediate viscosity range between water and oil (several mPa · S to several thousand mPa · S) has been developed. This has the property that the viscosity is reduced by the rotation of the tip ball and the ink flows out smoothly,
This is a ballpoint pen using a relatively low-viscosity water-based ink having a so-called shear thinning property. However, since this ink has a drawback that the ink easily dries, a cap for sealing the writing tip is usually required. In addition, the amount of outflow of ink is increased, and it is necessary to increase the diameter of the ink storage tube and increase the amount of ink to be filled in order to extend the writing life.
A medium-viscosity aqueous ballpoint pen is usually filled with a grease-like translucent non-drying substance called a follower at the rear end of the ink storage tube. It can be considered that evaporation from the gap of the ball holding portion is reduced.

As an improvement of the oil-based ball-point pen, a ball-point pen using a low-viscosity oil-based ink having excellent drying resistance is conceivable. However, the amount of the ink flowing out is increased and the ink storage tube is required to extend the writing life. It is necessary to increase the diameter of the ink and increase the filling amount of the ink. Also, due to the low viscosity of the ink, if the tip side faces downward and there is a gap between the tip ball and the tip holding portion, the ink will bleed (DC) or the amount of ink flowing out during writing will increase. There are drawbacks.

That is, when a water-based ballpoint pen having a shear-thinning property and an oil-based ballpoint pen having a low viscosity are mounted in a two-shaft cylinder due to a thick ink container tube, the barrel becomes extremely thick, resulting in portability and ease of use. There is a problem that becomes worse. In addition, since both the medium-viscosity aqueous ink and the low-viscosity oil-based ink have low viscosities, there is a phenomenon that the ink easily flows backward or direct current.

[0006] A liquid applicator using a white pigment to correct a mistake or the like is known. In the related art, since a white pigment and a solvent are easily separated from each other, ink, a ball, and the like are sealed in a flexible container in this kind of liquid applicator, and it is necessary to shake and agitate the liquid applicator before use. In addition, in order to discharge the ink, the pressure is applied by pressing the side of the container.

[0007]

SUMMARY OF THE INVENTION A first object of the present invention is to mount two large-diameter ball-point rifles in a barrel so that the tips of the tips protrude from the lips at both ends of the barrel. It is possible to provide a ballpoint pen which is filled with a medium-viscosity aqueous or low-viscosity oil-based ink in a portable and easy-to-use appearance. A second object of the present invention is to provide a ballpoint pen refill for writing errors and a refill for writing ballpoint pen on a single shaft without the need for agitation and the trouble of pressing the side of the container. It is possible to provide a simple double-headed ballpoint pen.

[0008]

The present invention has the following arrangement to achieve the above object. The ballpoint pen according to the first aspect of the present invention is a ballpoint pen in which two ballpoint pen refills are mounted in the barrel so that the tips of the tips protrude from the mouth portions at both ends of the barrel. The tube has a small diameter portion at the tip side of the tip and a large diameter portion at the back of which is filled with ink. The cross-sectional shape of the large diameter portion of the two refills is a roughly oval cross section of the inner circumference of the barrel. An aqueous ballpoint pen ink or a low-viscosity oil-based ink having a so-called shear thinning viscosity is formed in a substantially inscribed state in the surface shape, and the viscosity is reduced by the rotation of the tip ball accompanying writing and flows out in the ink storage tube. The back end of the ink is filled with a follower made of a grease-like translucent non-drying substance that moves following the consumption of the ink accompanying writing.

According to a second aspect of the present invention, there is provided a ballpoint pen according to the first aspect, wherein the refill includes a tip for holding the tip ball, and the tip ball having an inner edge of a ball holding portion at the tip end. Always press and close
It has a spring provided to release the close contact state during writing.

According to a third aspect of the present invention, there is provided a ballpoint pen according to the first aspect, wherein the refill is provided with a valve chamber in which a ball valve is loosely fitted in contact with a rear end of the chip. At the rear of the chamber, there is provided a ball receiving seat for preventing a backflow of ink due to the close contact of a ball valve, and a guide hole communicating from the ball receiving seat to the ink storage tube.

According to a fourth aspect of the present invention, there is provided the ball-point pen according to the first aspect, wherein the tail plug having a ventilation groove for communicating the inside of the shaft cylinder with the outside air at the rear end of the ink storage tube. At the same time, the rear ends of the tail plugs abut against the rear end of the lip, and the tip is held in a protruding state from the tip of the opposing lip.

According to a fifth aspect of the present invention, there is provided a ball-point pen according to any of the first to fourth aspects, wherein at least one of the refills of the ball-point pen is filled with a white gel-like ink in an ink storage tube. Consisting of

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As an example, the ink applied to the refill of a ballpoint pen of the present invention is an aqueous ink having a so-called shear thinning property and an oily ink having a low viscosity. As a second aspect, the ballpoint pen of the present invention includes a writing pen for correcting a typographical error, in which at least one of the ballpoint pens is filled with a gel ink having a white color, and a so-called water-based, oil-based ink, low-viscosity oil-based ink or ordinary oil-based material having a shear thinning property. It is provided by combining a writing pen with a writing pen filled with ink. Further, the white gel ink contains at least a white pigment such as titanium oxide and polymer hollow fine particles and a gelling agent, and is a white pigment that is blended so that sedimentation of the pigment is suppressed and fluidity is not impaired. Ink.

First, FIG. 1 to FIG. 3 show an embodiment of the present invention. In the figure, the refills 3a and 3b have basically the same configuration, and are formed by attaching chips having different ink colors and writing lines.

As shown in the drawing, the tip 8a is caulked so that the tip ball 9 is rotatably held with the tip ball 9 substantially in contact with a seat having a channel into which ink can flow. Further, the spring 10 is inserted into the chip inner hole, and the rear end of the shaft portion 18 is appropriately caulked so that the winding portion at the rear end of the spring 10 cannot be pulled out. (Caulking portion 19) Further, it is extremely important that the tip ball 9 comes into close contact with the inner surface of the ball holding portion of the chip for drying of the writing tip and for preventing direct current of ink. Therefore, the tip ball 9 is held. Grinding of the inner surface to improve the surface roughness of the inner surface of the chip and close contact accuracy by caulking, and secondary plastic working to increase the caulking accuracy are considered. In addition, a surface treatment or the like is taken into consideration for the surface in close contact with the tip ball.

The front end of the spring 10 becomes a straight rod portion 11, and the tip of the rod portion 11 contacts the rear end of the tip ball 9 in a pressed state. The tip ball 9 is brought into close contact with the inner edge of the ball holding portion of the chip 8a by the pressing.

The joint 4 has a tip 1a of the shaft portion 1 of the tip 8a.
An inner hole portion 22 for crimping 8 is formed. Further, a shaft portion 5 is formed at the rear end, and the shaft portion 5 is firmly fixed to the front end hole of the small diameter portion 15 of the ink storage tube 13.

A valve chamber 6 is provided behind the inner hole 22 of the joint 4 by loosely fitting the ball valve 12, and a tapered or spherical ball receiving seat 20 is provided behind the valve chamber 6. Hole 7
Are provided eccentrically with respect to the axis. A groove 2 is formed on one side of the inner wall of the valve chamber 6 so that ink flows in the axial direction.
1 is provided. When the tip 8a faces downward, the ball valve 12 that is loosely fitted in the valve chamber 6 contacts the tip of the shaft 18 of the tip in a state of being biased to the rear end, thereby forming an ink flow path to the tip bore. Then, the ink in the ink storage tube 13 flows into the chip inner hole through the groove 21, the ink flow path, and the like through the guide hole 7. Conversely, in the upward state, the ball valve 12
Is closely contacted with the ball receiving seat 20 to prevent the ink from flowing backward.

The ink container 13 is filled with ink 23 of a ball-point pen. Further, the rear end of the ink 23 is a grease-like translucent material that can move following the ink surface by contact with the ink surface as the ink is consumed. Follower 24 made of non-drying material
Is filled. Further, a resin follower rod 25 having a specific gravity substantially equal to that of the follower 24 is immersed in the follower 24 as necessary in order to prevent deformation due to dropping, knock impact, or the like. A tail plug 16a is fixed to the rear end of the ink storage tube 13. The tail plug 16a is provided with a ventilation groove 17a for communicating the inside of the ink storage tube 13 with the outside air.

The ink storage tube 13 is, for example, a transparent polypropylene resin molded product. In addition, the ink storage tube 13 is selected from a material having an excellent clear drain property. The large diameter portion 14a of the ink container 13 is a non-deformed one having a relatively large cross-sectional area.
Refills of two ballpoint pens are inserted into the inner circumference of the substantially oval outer diameter shaft of the barrel 1 without waste.

Next, the configuration of the ballpoint pen will be described. First, a tip 2a is fixed to one end of the barrel 1 by engagement with a projection or a groove formed therebetween, and a refill 3a is inserted from the other end of the barrel 1 so that the tip of the tip 8a is It protrudes from the front end opening of the portion 2a. Subsequently, the refill 3b is inserted from the other end of the barrel 1 from its tail plug 16b side,
The rear end of the tail plug 16b is in contact with the rear end of the lip 2a. In this state, the tip 2b is fixed to the other end of the barrel 1 by engagement with a protrusion or a groove formed therebetween. At this time, the tip 8b of the refill 3b projects from the tip end of the tip 2b, and the rear end of the tip 2b is connected to the refill 3a.
Abuts on the rear end of the tail plug 16a, and the tip is thus held in a protruding state from the respective tip.

[0022]

First, the ball-point feel 3a is a chip 8
With the ball valve 12 facing upward, the ball valve 12 is located at the ball receiving seat 20 of the valve chamber 6 and seals the guide hole 7, so that the ink is written upward and the back of the tip ball 9 of the chip runs out. Also, there is no backflow due to the head hanging on the ink. Therefore, when the tip 8a is turned downward, the ink can immediately flow out, and the writing is prevented from being rubbed. (By the way, in the structure without a ball valve, the ink acts in the backward direction when writing upwards, so that air is trapped in the chip and the ink does not follow immediately when writing downwards, causing scuffing.)

In a writing state in which the tip 8a is directed downward, the ball valve 12 abuts on one of the rear ends of the tip 8a, and the other side has a flow path through which ink can flow into the tip 8a. Then, the ink 23 that has entered the valve chamber 6 from the ink storage tube 13 through the guide hole 7 is guided to the back surface of the tip ball 9. In this state, the tip ball 9 is brought into close contact with the inner edge of the tip holding portion by the pressing of the rod shaft portion 11, so that the back surface of the tip ball is dried and the direct current of ink is prevented. Further, since the tip ball 9 is slightly retracted by the writing pressure, a gap is generated and ink can flow out, and the ink smoothly flows by rotation of the tip ball 9 by writing.

On the back surface of the tip ball 9, there is a channel (a seat for the tip ball having a plurality of ink inflow grooves penetrating toward the chip inner hole), and a rod shaft portion 11 passes through the center hole of the channel. . The ink in the chip is guided to the back surface of the tip ball 9 through the ink inflow groove and the gap between the center hole and the rod shaft portion 11.

[0025]

The configuration and operation of the ballpoint pen of the present invention are as described above, and it is possible to provide a ballpoint pen filled with a medium-viscosity aqueous or low-viscosity oily ink in a portable and easy-to-use appearance. . In addition, there is no backflow of ink and no direct current phenomenon, the drying resistance of the pen tip is maintained and the cap can be left for a long time without removing the cap. Is prevented.
Also, by using the white gel ink, there is no problem that the white pigment and the solvent are separated as in the conventional case, and there is no trouble in stirring the ink or pressing the side of the container. It is possible to provide a convenient double-headed ball-point pen in which a correction ball-point pen and a writing ball-point pen are mounted on one shaft.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an entire ballpoint pen according to an embodiment of the present invention.

FIG. 2 is an enlarged sectional view of one end of FIG.

FIG. 3 is a sectional view taken along the line AA in FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Shaft cylinder 2a Tip 2b Tip 3a Refill of ballpoint pen 3b Refill of ballpoint pen 4 Joint 5 Shaft 6 Valve chamber 7 Guide hole 8a Tip 8b Tip 9 Tip ball 10 Spring 11 Rod 12 Ball valve 13 Ink storage tube 14a Large Diameter part 14b Large diameter part 15 Small diameter part 16a Tail plug 16b Tail plug 17a Vent groove 17b Vent groove 18 Shaft part 19 Caulking part 20 Ball receiving seat 21 Groove 22 Inner hole part 23 Ink 24 Follower 25 Follower rod

Claims (5)

[Claims] 1. A ball-point pen having two ball-point pen refills mounted in a shaft cylinder such that tips of the tips protrude from the mouth portions at both ends of the shaft cylinder, wherein the ink storage tube of the refill has a small diameter toward the tip side. The part is formed by forming a large diameter part behind which ink is filled,
The cross-sectional shape of the two refills, including the large diameter portions, is substantially inscribed in the substantially oval cross-sectional shape of the inner circumference of the barrel, and the viscosity of the ink storage tube is increased by the rotation of the tip ball accompanying writing. A grease-like semi-transparent ink that is filled with an aqueous ballpoint pen ink or a low-viscosity oil-based ink having a so-called shear-thinning property, which is discharged at a lower rate, and moves at the rear end of the ink following the consumption of the ink accompanying writing. A ballpoint pen filled with a follower made of a dry substance. 2. The refill is provided such that the tip ball always presses and comes into close contact with the tip holding the tip ball and the inner edge of the ball holding portion at the tip tip, and the contact state is released during writing. 2. The ballpoint pen according to claim 1, comprising a spring. 3. A refill is provided with a valve chamber in which a ball valve is loosely fitted in contact with a rear end of a chip, and a ball valve is closely attached to a rear portion of the valve chamber to prevent a backflow of ink and a ball receiving seat. 2. The ballpoint pen according to claim 1, further comprising a guide hole extending from the seat to the ink storage tube. 4. A tail plug having a ventilation groove communicating between the inside of the barrel and the outside air is fixed to the rear end of the ink storage tube, and each refill has a rear end of the tail plug and a rear end of a lip. 2. The ball-point pen according to claim 1, wherein the tip is held in a protruding state by contacting the tip with the tip of the mouth portion. 5. The ballpoint pen according to claim 1, wherein at least one of the refills of the ballpoint pen is formed by filling a white gel-like ink in an ink storage tube.