JP2007276117A - Ball-point pen tip - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a ball-point pen tip having effects, in which no clogging of ink develops and its stable delivering is obtained. <P>SOLUTION: In the ball-point pen tip, which comprises at least a ball serving as a coating member and a ball holder, which rotatably holds the ball under the state that some part thereof is stuck out of an opening, under the condition that both the ends of the ball holder communicate with each other by a communicating hole as an ink passage, an inwardly projecting part serving as the terminal point of rearward movement of the ball is provided at the midway of the communicating hole, a plurality of ink-flowable grooves, which communicates the smaller diametral part of the communicating hole formed by the inwardly projecting part and the ball holding chamber having the ball arranged therein with each other and does not communicate with the hind part of he inwardly projecting part, the opening of the groove of the communicating hole to the smaller diametral part has a portion slightly inclined ahead. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method of manufacturing a ballpoint pen tip including at least a ball as an application member and a ball holder that rotatably holds the ball in a state where a part of the ball protrudes from an opening.

The ballpoint pen tip enables ejection by using a gap between the ball holding chamber and a ball held in the ball holding chamber as an ink flow path. Therefore, the outermost part of the ink passage for supplying ink to the ball holding chamber is processed near the wall surface.
JP-A-10-217665

  Processing of the ink passage for supplying ink to the ball holding chamber is performed by a shearing process called broaching. However, since force is applied to obtain shearing, a portion that is not processed, for example, the trueness of the ball holding chamber is processed. There was a problem that the circular shape was lost, the gap with the ball became non-uniform, and the handwriting was disturbed or the ink leaked.

  That is, the present invention is summarized as a ballpoint pen tip manufacturing method in which an ink passage for supplying ink to a ball holding chamber of a ball holder that holds a ball as a writing member is formed before the ball holding chamber is formed.

  Since the ink path that will be sheared in the subsequent process is formed in advance, the influence of the shearing process can be reduced as much as possible after the subsequent machining, and clean handwriting can be formed with stable ink ejection. is there.

  The ballpoint pen tip of the present invention uses a pipe material in which a non-circular hole is formed in advance. Of course, the formation of a radial ink passage called a ditch is usually performed in advance.

An example will be described based on the drawings.
What is described in FIG. 1 is a pipe body 1 manufactured by drawing. An appropriate shape can be formed by the shape of the insert at the time of drawing. FIG. 2 shows a longitudinal cross-sectional view. In this example, a regular pentagonal hole 2 is formed, and the hole 2 is formed in the entire hand direction along the pipe body.
As shown in FIG. 3, the part which becomes a ball holding chamber is then formed by cutting. That is, the ball holding chamber planned portion 3 is formed by forming the opening portion of the hole 2 in a circular shape in cross section by cutting with an appropriate depth. A basic ballpoint pen tip shape is formed by disposing the ball 4 in a portion to be a ball holding chamber and caulking the tip 5 so that the ball 4 is retracted.

  Since the ball-point pen tip created in this way is formed in advance with an inner process that becomes a shearing process, the ink flow path can be formed uniformly and a good handwriting is formed.

External view of pipe material. The longitudinal cross-sectional view of FIG. I-I 'line cross-sectional view of FIG. The longitudinal cross-sectional view which shows the state after ball holding chamber formation.

Explanation of symbols

1 Pipe body 2 Hole 3 Ball holding chamber planned part 4 Ball 5 Tip part

Claims (2)

A method of manufacturing a ballpoint pen tip, wherein an ink passage for supplying ink to a ball holding chamber of a ball holder for holding a ball as a writing member is formed before the ball holding chamber is formed. 2. The method of manufacturing a ballpoint pen tip according to claim 1, wherein the ink passage is formed by a pipe forming process by extrusion or drawing.

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