JPH10236061A - Ball-point pen - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce cost by forming recessed deformation parts on two portions in the axial direction through plastic deformation at an appropriate position of the outer periphery of an ink reservoir pipe of the chip rear end, providing a ball valve at a partial protrusion of the inner peripheral part thereof, filling ink of a low density, and arranging a grease follower. SOLUTION: The chip 10 of a ball-point pen is provided at the tip end and an ink reservoir pipe 2 is also provided at the rear thereof, recessed deformation parts 3, 5 are formed in the axial direction through plastic deformation at the outer peripheral part of the ink reservoir pipe 2 at an appropriate rear position from the rear end of the chip 10. The deformation part 3 is formed with a partial protrusion 4 in the inner peripheral part by partial deformation, and the deformation part 5 is formed with an entire ball receiving seat 6 in its inner peripheral part by an entire circumferential deformation, and further a ball 9 is loosely put in a valve chamber 7 formed between the protrusion 4 and the ball receiving seat 6. The ink reservoir pipe 2 is filled with low viscosity ink 15, and a grease-like follower 16 is disposed at the ink rear end, which follows with the consumption of ink.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ballpoint pen filled with a low-viscosity ink.

[0002]

2. Description of the Related Art The ink of a conventionally known oil-based ballpoint pen has a high viscosity, and a small amount of ink flows out by rotation of a tip ball during writing. In addition, there are problems such as unevenness, unevenness of writing lines, low density, and high writing pressure. In addition, as an improvement of the conventional oil-based ballpoint pen, a relatively low-viscosity ink is used. Are known. However, since this ink has a drawback that the ink easily dries, a cap for sealing the writing tip is required. Therefore, a low-viscosity oil-based ink with excellent drying resistance is conceivable. However, the amount of the ink flowing out is also large, and in order to increase the writing life, the diameter of the ink storage tube is increased to increase the amount of ink loaded. . The same applies to the water-based ink. However, since the viscosity of the ink is smaller than that of the conventional oil-based ballpoint pen ink, 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 the weight and impact of the ink. For this purpose, a grease-like follower is provided at the rear end of the ink, which normally moves following the consumption of the ink during writing, but suppresses the backflow of the ink against its own weight or impact. However, even when the follower is provided, if the ink on the back side of the tip ball runs out when writing upward, there is a danger that the ink or the head will be added directly, causing a remarkable backflow and soiling the hands and clothes. In addition, since the viscosity of the ink is low and the amount of outflow is large, if the tip side faces downward and a gap is formed between the tip ball and the tip holding portion, the ink may bleed (direct current). Further, there is a problem that the ink on the back surface of the tip ball tends to flow backward after upward writing or after an impact such as knocking or dropping, so that writing blur occurs.

FIGS. 5 to 7 show a conventional ballpoint pen, which has already been disclosed by the present applicant. In this ball-point pen, a tip of a ball-point pen is fixed to the tip of an ink container filled with ink, and a valve member is disposed in the ink container tube so as to face the rear end of the chip. A ball receiving seat is formed at the rear end of the valve chamber in communication with the guide hole, and a resilient piece which has a slit portion at a required location in front of the valve chamber and is elastically displaceable is formed. A protrusion is formed on the inner surface of the elastic piece, and the ball valve is loosely fitted into the valve chamber between the ball receiving seat and the protrusion. The valve member has a conical or spherical ball receiving seat that comes into close contact with the ball valve when the ball valve comes into contact with the ball valve. The ball valve is easily fitted into the valve chamber by being easily inserted into the valve chamber, disposed in the tube and restrained at the outer periphery of the front part, so that the ball valve cannot be pulled out and is loosely fitted into the valve chamber.

[0004]

The ballpoint pen using the low-viscosity ink of the present invention is a refill that can be mounted on a cap-type writing instrument or a knock-type writing instrument that allows the writing tip to protrude and retract from the tip of the shaft. In addition, the conventional one has a problem that the cost is high because it is constituted by a structure having a joint between the tip and the ink storage tube, or by the structure of the above-mentioned conventional example or an injection molded product integrally having the joint part. Is to be resolved.

[0005]

The present invention has the following arrangement to solve the above-mentioned problems. The ballpoint pen according to the first aspect of the present invention is provided with a tip of a ballpoint pen at the tip and an ink storage tube at the rear, and an outer peripheral portion of the ink storage tube at an appropriate position behind the rear end of the tip by plastic deformation.
At the same time, a recessed deformed portion is formed at the location, a partial ridge is formed at the inner circumference at the front location, and a full-circle ball receiving seat is formed at the inner circumference at the rear location. A ball valve is loosely fitted in a valve chamber formed between the ridge portion and the ball receiving seat. The ink storage tube is filled with low-viscosity ink, and ink is consumed at the rear end of the ink. And a grease-like follower that follows the ink is provided.

According to a second aspect of the present invention, there is provided a refill of a knocking ballpoint pen according to the first aspect, wherein the refill of the knocking ballpoint pen is provided with a small diameter provided in a tip end portion of a spring at an inner hole of a tip. Part presses the rear end of the tip ball, and the tip ball comes into close contact with the inner edge of the ball holding portion at the tip of the tip, preventing ink from flowing out. A mechanism is provided to prevent direct current and reverse flow of the ink so that the state is released and the ink can flow out with the rotation of the tip ball.

According to a third aspect of the present invention, there is provided the refill of a knocking ballpoint pen according to the second aspect of the present invention, wherein the refill of the knocking ballpoint pen has a linear rod shaft formed in front of the spring. The tip of the rod shaft portion presses the rear end of the tip ball so that the tip ball comes into close contact with the inner edge of the ball holding portion at the tip of the tip.

[0008]

1 to 3 show a ball-point pen according to a first embodiment of the present invention. First, a tip 10 of a ball-point pen and an ink storage tube 2 are provided at the tip and an outer peripheral portion of the ink storage tube 2 is plastically deformed at an appropriate rear position from the rear end of the tip 10 to form two recessed deformed portions 3 in the axial direction. 5 are formed, and the deformed portion 3 is partially deformed to form a partial ridge 4 on its inner peripheral portion, and the deformed portion 5 is formed on its inner peripheral portion by full-circular deformation. All-round ball seat 6
Is formed, a ball valve 9 is loosely fitted into a valve chamber 7 formed between the ridge portion 4 and the ball receiving seat 6, and the ink storage tube 2 is filled with low-viscosity ink 15. A grease-like follower 16 is provided at the rear end of the ink and follows the ink as the ink is consumed. If necessary, a resin follower rod having substantially the same specific gravity as the follower is immersed in the follower 16. (Not shown)

As the ink storage tube 2, an extruded tube made of polypropylene resin or a metal tube is used. The plastic working of the ink container 2 made of polypropylene resin is performed by heat and pressure using a tool.

FIG. 4 shows a ballpoint pen according to a second embodiment of the present invention. The tip 10a is caulked so that the tip ball 14 is rotatably held with the tip ball 14 substantially in contact with a seat having a channel into which ink can flow. (Ball holding portion 14a) and tip 10a
The spring 17 is inserted into the inner hole of the
The rear end of 1a is appropriately caulked (caulked portion 11b), and the rear end of the spring 17 is provided so as not to be pulled out.

A linear rod 17a is formed in front of the spring 17, and the front end of the rod 17a is pressed against the rear end of the ball 14. Note that the tip ball 14 is pressed by the ball holding portion 14a of the tip 10a.
(Formed by caulking or the like).

[0012]

FIGS. 1 and 2 show a state in which the tip 10 is turned upward. At this time, the ball valve 9 is located in the ball receiving seat 6 of the valve chamber 7 and seals the guide hole 8, so that the ball valve 9 is written upward. Even if the ink on the back surface of the tip ball 14 of the chip runs out, the ink is caught by the head and does not flow backward. Therefore, when the chip 10 in FIG. 3 is turned downward, the ink can immediately flow out, and the writing is prevented from being flared. (By the way, in the structure without the ball valve, the ink acts in the backward direction in the upward writing, so that air is entrapped in the chip, and the ink does not immediately follow in the downward writing, resulting in rubbing.)

In a writing state in which the tip 10a is directed downward as shown in FIG. 4, the ball valve 9 comes into contact with the ridge 4, and the ball valve 9 comes into the valve chamber 7 from the ink storage tube 2 via the guide hole 8. The entered ink flows into the chip inner hole through a gap formed between the ridges. On the back surface of the tip ball 14, there is a channel (a seat for the tip ball having a plurality of ink inflow grooves penetrating toward the chip inner hole).
The rod 17A of the spring 17 is provided in the center hole of the channel.
Penetrates. The ink in the tip passes through the ink inflow groove and the gap between the center hole and the rod shaft portion 17a, and the tip ball 14
You will be guided to the back.

In this state, the rod shaft 1 of the spring 1
When the tip 7a is pressed, the tip ball 14 becomes the ball holding portion 1 of the chip.
Since it is close to the inner edge of 4a, direct current of ink is prevented. In addition, the tip ball 14 is slightly retracted by the writing pressure, so that a gap is generated and ink can flow out, and the ink flows out by rotation of the tip ball 14 by writing, and there is no dent,
High-density writing becomes possible.

[0015]

The configuration and operation of the ballpoint pen according to the present invention are as described above. The mechanism for preventing direct current and backflow of ink can be easily formed in an automatic assembling machine by plastic deformation of the ink container tube. As a result, it is possible to provide a ballpoint pen at low cost. In addition, when the ink storage tube is a transparent tube made of polypropylene resin or the like, the ink can be seen up to the rear end of the chip, and there is an advantage that the ink remaining amount can be recognized as in the case of the conventional oil-based ballpoint pen.

[Brief description of the drawings]

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

FIG. 2 is an enlarged sectional view of a forward part of FIG. 1;

FIG. 3 is an enlarged cross-sectional view of a tip portion of the ballpoint pen according to the first embodiment, showing a state where a chip is directed downward.

FIG. 4 is an enlarged cross-sectional view of a tip portion of a ballpoint pen according to a second embodiment, showing a state where a chip is directed downward.

FIG. 5 is a longitudinal sectional view showing the entire ballpoint pen of the conventional example, and shows a state in which a chip is directed upward.

FIG. 6 is an enlarged cross-sectional view of a forward part of FIG. 5;

FIG. 7 is an enlarged cross-sectional view of a tip portion of a conventional ballpoint pen, and shows a state where a tip is directed downward.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ball-point pen 2 Ink storage tube 3 Deformation part 4 Protrusion part 5 Deformation part 6 Ball receiving seat 7 Valve room 8 Guide hole 9 Ball valve 10 Chip 10a Chip 11 Shaft part 11a Shaft part 11b Caulking part 12 Inner hole 13 Ink groove 14 tip ball 14a ball holding portion 14b receiving seat 15 ink 16 follower 17 spring 17a rod shaft portion 17b winding portion 20 ballpoint pen 21 valve member 22 valve chamber 23 guide hole 24 elastic piece 25 slit portion 26 ridge 27 ball receiving seat 28 Ball valve

Claims (3)

[Claims] 1. A tip of a ball-point pen and an ink storage tube at the rear end are provided, and two concave portions are formed by plastic deformation on an outer peripheral portion of the ink storage tube at a position appropriately rearward from a rear end of the tip. In addition, a partial ridge portion is formed on the inner peripheral portion of the front portion, and a full-circle ball receiving seat is formed on the inner peripheral portion of the rear portion, and the ridge portion and the ball receiving seat are formed. A ball valve is loosely fitted in a valve chamber formed between the ink tank and the ink storage tube. The ink storage tube is filled with low-viscosity ink, and a grease-like follower that follows the ink as the ink is consumed at the rear end of the ink. A ball-point pen characterized by being arranged. 2. A small-diameter portion provided at a forward end of a spring presses a rear end of a tip ball in an inner hole portion of a tip, and the tip ball comes into close contact with an inner edge of a ball holding portion at a tip end of the tip to form ink. A mechanism that prevents outflow and prevents direct current and backflow of ink so that ink can flow out with rotation of the tip ball by releasing the close contact between the tip ball and the inner edge of the ball holding portion of the tip by writing pressure. A part is provided.
The ballpoint pen described in 1. 3. A straight rod portion is formed in front of the spring, and the tip of the rod portion presses the rear end of the tip ball, so that the tip ball comes into close contact with the inner edge of the ball holding portion at the tip end. The ballpoint pen according to claim 2, wherein the ballpoint pen is configured to perform the following.