JPH1058885A - Ball point pen tip - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ball point pen tip to be manufactured at low cost and durable for the strong stroke of a pen for a long period of time for which the precision mechanical working or the sophisticated working is not required and in which the unevenness of quality is scarcely generated. SOLUTION: A ball point pen tip is composed of a globular ball 16, a hollow outer tube 11 having the inner diameter larger than the outer diameter of the ball and one end drawn inward and one hollow inner tube 13 or two hollow inner tubes or more having the inner diameter smaller than the outer diameter of the ball, and the inner tube 13 is fixed in the outer tube 11 by caulking or the like. The end face 13a of the inner tube is positioned on the inner side of an end face 17 of the outer tube in the axial direction, and a ball housing 18 for retaining the ball between the drawn section 7 of the outer tube 11 and the inner tube end 13a is formed by the arrangement. Also the dimension of a clearance 12 between the inside 14 of the inner tube 13 and/or the outer tube 11 and the inner tube 13 is so set as to generate capillary force.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ballpoint pen tip for supplying ink to a ball at a tip portion by capillary force.

[0002]

2. Description of the Related Art The tip of a ball-point pen (hereinafter referred to as a ball-point pen tip) comprises a ball housing for holding a ball and an ink supply unit for supplying ink (oil-based or water-based) to the ball. Heretofore, such a ball-point pen tip has been manufactured by machining as exemplified in, for example, Japanese Patent Publication No. 62-16837. That is, the ball housing of the ball-point pen tip is formed by drilling a space in which a ball fits at one end of a solid round bar, forming a ball seat seat for supporting the ball on the inner surface thereof, and further forming a ball seat seat along a part thereof. The groove is manufactured by processing a plurality of grooves, and ink is uniformly supplied to the ball from the grooves. The ink supply section is formed by drilling through a small hole from the ball housing to the end of the ballpoint pen tip.

[0003] The above-mentioned mechanically-processed ball-point pen tip has a problem that extremely high precision is required for processing the ball housing and an extremely thin and long hole is required for processing the ink supply section. For this reason, each manufacturing facility
In addition to being expensive, there is a problem that adjustment and quality control of the apparatus are difficult, and consumables (tools and the like) increase, resulting in a high running cost and a high manufacturing cost of a ballpoint pen tip.

[0004] In order to solve the above-mentioned problems, an ink conducting core is fixed inside a thin tube, ink is supplied by the ink conducting core, and at the same time, a ball is held at the tip of the ink conducting core. In addition, ballpoint pen tips designed to reduce costs have been invented and filed (for example, Japanese Utility Model Publication No. 59-24556, Japanese Utility Model Publication No. 60-3).
No. 9268, No. 61-26079, No. 2-3
06).

For example, as shown in FIG. 4, the "ballpoint pen tip" of Japanese Utility Model Publication No. 2-306 is a center of a tip holder 3 to which a pipe-like tip 1 holding a ball 2 at a tip end portion 1b is attached. In the hole 3a, a rod 4 made of a synthetic resin whose tip is in contact with the rear side of the ball, an elastic liquid-containing member 5 for urging the ball forward through the rod member, and an ink guide member for ink connection with the elastic liquid-containing member. 6 at least, and at least the ball 2 has a tip
The diameter at least at the front end of the center hole 1a of the pipe-shaped tip is made larger than the diameter of the ball so as not to hinder backward displacement until it is flush with the tip of the ball.
In this figure, reference numeral 4a denotes a rear end of the rod-shaped body 4, and 7 denotes a front end of the barrel.

[0006]

However, the above-mentioned prior art ball-point pen tips have a particularly high writing power because the writing power when the ball-point pen is used acts on the ink conducting core (for example, the synthetic resin bar 4) via the ball. When the value is high, there is a problem that the ink conduction core is degraded due to use for a long time, and the ball is depressed inside so that the ball can be used.

The present invention has been made to solve such a problem. In other words, an object of the present invention is to provide a ball-point pen tip that does not require precise machining or complicated processing steps, has less variation in quality, has a low manufacturing cost, and can withstand high writing power for a long time. It is in.

[0008]

According to the present invention, a spherical ball, a hollow outer tube having an inner diameter larger than the outer diameter of the ball and having one end narrowed inward, and an inner diameter fixed in the outer tube. A hollow inner tube smaller than the outer diameter of the ball, wherein the end surface of the inner tube is located axially inward from the end surface of the outer tube to hold the ball between the constricted portion of the outer tube and the inner tube end. Forming a ball housing, wherein the gap inside the inner tube and / or the gap between the outer tube and the inner tube is sized to generate a capillary force;
A ballpoint pen tip is provided.

According to a preferred embodiment of the present invention, the number of the hollow inner tubes is one or more, and the outer tube has a plurality of circumferentially spaced caulking portions. The part fixes the inner tube.

[0010] In the structure of the present invention, a cavity for generating a capillary force is formed by combining hollow tubes in a multiplex manner.
It is arranged so that ink can be supplied to the balls, has a very simple structure without a drilling step, has little variation in quality, and as a result, can reduce costs and improve productivity. In a preferred embodiment, the ink flow path of the capillary formed by multiplexing the hollow tubes is an annular gap formed inside the inner tube and / or between the outer tube and the inner tube. In addition, the width is sufficiently small to obtain the necessary capillary force, and the total cross-sectional area of the ink supply channel is large, so that the ink supply amount necessary for the rotation of the ball can be sufficiently secured.

In addition, since the ball housing and the ink supply portion can be formed by the rigid outer tube and the inner tube made of metal or the like, even if the writing power is particularly high, there is almost no settling of the inner tube and the ball does not collapse. Can withstand high writing power for a long time.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. In the drawings, common parts are denoted by the same reference numerals. FIG. 1 is a configuration diagram showing a first embodiment of the present invention. In this figure, (A) is a longitudinal sectional view of a double-pipe ball-point pen tip constituted by two hollow pipes, and (B) is its A-
It is a cross-sectional view in the A line. As shown in this figure, the ball-point pen tip 10 of the present invention has a spherical ball 16, 1.
It consists of one hollow outer tube 11 and one hollow inner tube 13.
The outer tube 11 has an inner diameter larger than the outer diameter of the ball 16, and has a narrowed portion 17 (a crimped portion in the figure) narrowed inward at one end (the left end in the figure). Further, the outer tube 11 has a plurality of different caulking portions 15 spaced apart in the circumferential direction. The caulking portion 15 may be provided at one location in the axial direction, or at two or more locations. The outer tube 11 is made of metal and may be formed in advance into a hollow straight tube by a separate process.

The hollow inner tube 13 has an inner diameter smaller than the outer diameter of the ball 16 and is fixed in the outer tube 11 by a caulking portion 15 so as not to move in the axial direction. This inner tube 13
Is preferably made of metal like the outer tube 11, but other straight tubes, for example, a plastic tube can also be used.
The end face 13a (the left end in this figure) of the inner pipe 13 is the outer pipe 1
1 is located axially inward from the end face (restricted portion 17) of the outer tube 11, and the ball 16 is located between the restricted portion 17 of the outer tube 11 and the inner tube end 13a.
Is formed. In addition, each of the tubes 11 and 13 is set to have such a size that the inner side 14 of the inner tube 13 and / or the gap 12 between the outer tube 11 and the inner tube 13 generate a capillary force. In FIG. 1, a gap 12 is an annular gap having a capillary force necessary for supplying ink to the ball 16, and a gap 14 is an inner tube 13 having a hollow capillary force and supplying ink to the ball. It is an inner space.

FIG. 1 (C) is another embodiment of FIG. 1 (B). As shown in this figure, it is more preferable to insert a monofilament 19 into the inner side 14 of the inner tube 13 for the purpose of enhancing the capillary force. This monofilament 19 is made of metal or plastic, and is particularly inserted into the hollow of the inner tube 13 without being fixed by caulking or the like, thereby adjusting the gap between the inner surface of the inner tube 13 and the capillary force. Can be strengthened. The cross-sectional shape of the monofilament 19 may be circular as shown, or may be any other shape, for example, a triangle, a square, or the like.

FIG. 2 is a configuration diagram showing a second embodiment of the present invention. In this figure, (A) is a longitudinal sectional view of a multi-tube type ball-point pen tip constituted by eight hollow tubes, and (B) is a transverse sectional view taken along the line BB.
In this figure, the ballpoint pen tip 10 of the present invention comprises a spherical ball 16, one hollow outer tube 11, and seven hollow inner tubes 13. One of the seven hollow inner tubes 13 is located at the center of the outer tube 11, and the remaining six surround it. Further, the entire seven hollow inner tubes 13 are fixed by the caulking portion 15 so as not to move in the axial direction. Furthermore,
End portions 13a of seven hollow inner tubes 13 and throttle portions 1 of outer tubes 11
Ball housing 18 for holding ball 16 between
Are formed. Further, in this figure, the end surface 13a of the inner tube 13 forming the ball housing 18 is processed obliquely, but the present invention is not limited to this, and may be cut vertically. Other configurations are the same as those of the ballpoint pen tip of FIG.

That is, in the ball-point pen tip 10 shown in FIG. 2, the inner tube 14 and / or the gap 11 between the outer tube 11 and the inner tube 13 are formed by inserting seven inner tubes 13 into the outer tube 11. It is formed in such a size as to generate a force, and generates a capillary force necessary for supplying ink to the ball 16.

FIG. 3 is a configuration diagram showing an example of using the ballpoint pen tip of the present invention. That is, this drawing is a vertical cross-sectional view in which the ballpoint pen tip 10 according to the first and second embodiments is incorporated in a pen body as a writing implement. In FIG. 3, 1
1 is an outer tube of a ballpoint pen tip, 16 is a ball, 1
7 is a caulking portion for preventing the ball 16 from falling off, 15 is a caulking portion for fixing the outer tube 11 and the inner tube 13 and tightening the whole, 7 is an ink introduction core connected to the ballpoint pen tip 10 and has a capillary. Supplies ink necessary for the rotation of the ball by flowing along a multi-capillary tube through an ink introduction core. Reference numeral 8 denotes a holder for fixing the ballpoint pen tip 10, which has a role of maintaining the connection with the ink introduction core 15.

As exemplified in the above two embodiments,
By combining the hollow tubes 11 and 13, the annular gaps 12 and 14 formed from the contact point generate capillary force. Therefore, these gaps 12 and 14 are used as ink supply flow paths necessary for ink supply, and are formed on the ball 16. Ink can be supplied. Therefore, as compared with the technology manufactured by the conventional drilling process, the process is simple, the quality is easily controlled, and the cost reduction can be calculated.

That is, the configuration of the present invention comprises the hollow tube 11,
13 are formed in such a manner as to form capillaries 12 and 14 for generating a capillary force, and are arranged so that ink can be supplied to the ball 16. Variations are reduced, and as a result, costs can be reduced and production can be improved.

Further, since the ball housing 18 and the ink supply portions 12 and 14 can be formed by the rigid outer tube 11 and the inner tube 13 made of metal or the like, even if the writing power is particularly high, the inner tube 13 is hardly sagged. As a result, the ball 16 does not collapse and can withstand high writing power for a long time.

It should be noted that the present invention is not limited to the above-described embodiment, but can be variously modified without departing from the gist of the present invention.

[0022]

As described above, in the ball-point pen tip of the present invention, the capillarity is obtained by the gaps 12 and 14 generated by arranging a plurality of hollow tubes 11 and 13, and the space 18 in which the ball 16 can be inserted. Can be set. The ballpoint pen tip is completed by fixing the arranged hollow tubes 11 and 13 and caulking the inserted ball 16 so as not to fall off. Therefore, unlike the conventional technology, the process such as drilling can be omitted altogether, so the structure is simple, the reliability of quality is high, and the cost reduction can be calculated. Can be.

Therefore, the ballpoint pen tip of the present invention can be manufactured without requiring precise machining and complicated machining steps.
It has excellent effects such as low quality variation, low manufacturing cost, and high durability for a long time.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a first embodiment of the present invention.

FIG. 2 is a configuration diagram showing a second embodiment of the present invention.

FIG. 3 is a configuration diagram showing an example of using the ballpoint pen tip of the present invention.

FIG. 4 is a configuration diagram of a conventional ballpoint pen tip.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 tubular tip 2 ball 3 tip holder 4 synthetic resin rod 5 elastic liquid containing 6 ink guide member 7 ink introduction core 8 holder 10 ballpoint pen tip 11 hollow outer tube 12 gap between outer tube and inner tube 13 hollow inner tube 14 inside Inside of tube 15 Caulked portion 16 Ball 17 Restricted portion (Caulked portion) 18 Ball housing 19 Monofilament

Claims (2)

[Claims] 1. A spherical ball, a hollow outer tube having an inner diameter larger than the outer diameter of the ball and one end narrowed inward, a hollow inner tube fixed in the outer tube and having an inner diameter smaller than the ball outer diameter, Wherein the end surface of the inner tube is located axially inward of the end surface of the outer tube to form a ball housing for holding a ball between the constricted portion of the outer tube and the end of the inner tube; A ball-point pen tip, wherein a gap between the inner and / or outer tube and the inner tube is set to a size that generates a capillary force. 2. The hollow inner tube is one or two or more, and the outer tube has a plurality of caulking portions spaced apart in a circumferential direction, and the inner tube is fixed by the caulking portions. The ballpoint pen tip according to claim 1, wherein: