JP3034479B2 - Pen tip using ball as writing medium - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pen tip portion using a ball such as a ball pen, an applicator or a paste as a writing medium.
More specifically, the present invention relates to a pen tip having an inner wall surface at the tip end edge having a spherical shape similar to a ball.

[0002]

2. Description of the Related Art A ball is used as a writing medium, and a tip of the tip is swaged inward with a part of the ball protruding from the tip of the ball, thereby holding the ball rotatably. As a structure for preventing ink leakage when not in use, the inner wall of the tip end edge that comes into contact with the ball is formed into a spherical shape identical to the ball, and the tip of a writing implement that improves the valve function at the tip end includes: For example, as described in Japanese Patent No. 2524572, there is a manufacturing method in which the inner wall surface is deformed into a spherical shape having the same shape as a ball by staking with a staking jig inserted from the rear end side of the chip. It has been disclosed.

[0003]

In the above prior art, in order to obtain the same spherical shape as the ball on the inner wall surface of the tip end edge of the chip, it is necessary to apply a shock enough to move the ball by a required amount. In other words, the damage to the tip edge of the chip may be large and cracks may occur. Also, depending on the uneven thickness of the tip end edge or the misalignment of the ball with the rear end side hole and the ball,
There is a problem that the amount of deformation of the inner wall surface is not uniform.

[0004] In view of the above problems, the present invention has a uniform deformation amount, and does not cause cracks or other adverse effects on the chip.
Still another object of the present invention is to provide a pen tip which can be easily manufactured and has a writing medium using a ball obtained by deforming the inner wall surface of the tip end edge into the same spherical shape as the ball.

[0005]

In order to achieve the above object, according to the present invention, the tip of the chip is crimped inward to hold the ball, and then the ball is inserted by a support inserted from the rear end of the chip. Abutting against the inner wall surface of the tip end edge, and contacting the outer wall surface of the tip end edge from the front of the tip, and by hitting down a hammering tool, the inner wall surface is formed into the same spherical shape as the ball. It is.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention relates to a pen tip portion in which a writing medium is a ball obtained by deforming the inner wall surface of the tip end edge into a spherical shape having the same shape as the ball.

Further, in the present invention, the outer wall surface is formed into a curved shape by making a contact surface which comes into contact with the outer wall surface of the tip end edge of the hammering tool into a curved shape and knocking down the hammering tool. It has a shaped structure.

[0008] A ball having a curved outer surface at the tip end edge.
In consideration of the problem of paper contact and the like, a pen tip using a brush as a writing medium discloses a tip made by barrel polishing, a tip sprayed with abrasive powder, and the like.

However, in the above-described method of barrel polishing or spraying abrasive powder to round the outer wall surface of the tip end edge,
At the time of processing, the tip end edge is deformed. Also,
Since the polishing powder adheres to the inner wall surface of the tip end edge after the treatment, a cleaning step must be provided.Furthermore, it is difficult to remove all while preventing deformation of the tip end edge during cleaning. is there.

The present invention may also be applied to a pen tip having a structure in which a ball is pressed against the inner wall of the tip end edge by a coil spring, or a pressing element or a movable element is provided between the coil spring and the ball. Alternatively, the ball may be pressed. It is also possible to use a structure in which the ball is rotatably held in the ball holding chamber by a ball seat or a support on the inner wall surface of the ball holding chamber known in the prior art. .

[0011]

Embodiments of the present invention will be described with reference to the drawings. A stainless steel chip 1 as shown in FIGS. 1, 2 and 3 is cut to form a tungsten car having a ball diameter of 1.0 mm.
The ball holding chamber 3 is formed so as to hold the ball 2 made of a carbide-based steel material, and an ink flow passage hole 5 is provided in the center of the bottom wall 4 of the ball holding chamber 3. Next, the tip end edge 7 was swaged inward by the swaging tool 6 so that a portion of the ball 2 was projected outward from the tip end edge 7 and held rotatably.

Subsequently, a support 8 is provided from the rear end 1f of the chip 1.
Is inserted and fixed so that the ball 2 comes into contact with the inner wall surface 7a of the tip end edge. Next, the hammering tool 9 having a spherical contact surface 10 that abuts against the outer wall surface 7b of the tip end edge from the tip side 1e of the tip 1 is downed in the direction of the arrow, and the inner wall surface 7a of the tip end edge is lowered. Was deformed into a spherical shape having the same shape as that of the ball, and further, the tip 1 was manufactured by deforming the outer wall surface 7b at the tip end edge into a curved surface having the same shape as the contact surface of the hammering tool 9.

[0013]

The pen tip portion using the ball of the present invention as a writing medium has the above-described structure, so that it does not give an unreasonable impact to the tip end edge and has the same shape as the ball on the inner wall surface of the tip end edge. Since the spherical shape can be obtained, there is almost no difference in the amount of deformation due to variation in the quality of the chip, and there are advantages that the valve mechanism at the tip end of the chip can be easily supplied with stable quality.

[Brief description of the drawings]

FIG. 1 is a manufacturing process diagram of caulking processing

FIG. 2 is a manufacturing process diagram of a main part of the tip of the writing instrument of the present invention.

FIG. 3 is a manufacturing process diagram of a main part of the tip of the writing instrument of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Writing instrument chip 2 Ball 3 Ball holding chamber 4 Bottom wall 5 Ink passage hole 6 Caulking tool 7 Tip tip edge 8 Support post 9 Hammering tool 10 Contact surface 7a Inner wall surface of tip tip edge 7b Outer wall surface of tip end edge 1e Tip end side 1f Tip rear end side

Claims (2)

(57) [Claims] A ball is rotatably held by swaging a tip end edge inward in a state where a part of the ball projects from the tip end in a ball holding chamber at the tip end. After crimping the tip edge of the tip inside,
The ball (2) is brought into contact with the inner wall surface (7a) of the tip end edge by the column (8) inserted from the tip rear end side (1f), and the outer wall surface (7e) of the tip end edge is inserted from the tip end side (1e). 7b), the inner wall surface is formed in a spherical shape having the same shape as the ball by downing a hammering tool (9) in contact with the ball.
Bo is characterized in that the - nib portion to the writing medium Le. 2. The hammering tool (9), wherein a contact surface (10) for contacting an outer wall surface (7b) of a tip end edge is curved, and the outer wall surface (7b) is hammered.
2. A pen tip as a writing medium according to claim 1, wherein said pen tip is deformed into a curved surface having the same shape as a contact surface of said ring processing tool.