JPS6115832B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a felt-tip pen that can be obtained quickly and inexpensively by simultaneously processing a barrel and a fiber bundle by extrusion molding.
The present invention relates to a method for manufacturing a felt-tip pen that facilitates the drawing process of the tip of the barrel to enable the insertion of a pen core such as a small book, and also allows for smooth ink flow.

In a felt-tip pen in which a barrel and a fiber bundle are integrally formed inside the barrel by extrusion molding, several air grooves are formed on the inner surface of the barrel along the longitudinal direction of the barrel. Therefore, if the tip of the barrel is drawn in this state, the air groove will be blocked, so instead of drawing, draw the tip of the barrel a as shown in Figure 1.
A method is used in which the tip of the fiber bundle b is shaved off to expose the inner fiber bundle b, the tip of the fiber bundle is hardened, and then shaved to directly form the pen nib c. However, according to this method, since the diameter of the fiber bundle b is large, although it is possible to form a pen for thick writing, it is difficult to form a pen for medium thick or thin writing.

In view of the above-mentioned drawbacks of the conventional art, the present invention provides a felt-tip pen in which a barrel and a fiber bundle are integrally formed, so that it is suitable for small books and the like like a normal felt-tip pen.

Now, the method of the present invention will be described below with reference to the drawings of the embodiment. The fiber bundle 3 is simultaneously formed by extrusion molding, and the shaft tube 1 containing the fiber bundle 3 is cut to a required length, and the rear end of the shaft tube is closed-molded by electric heating. Next, a screwdriver-like twisting tool 4 is inserted into the fiber bundle 3 through the open end of the barrel, and is rotated to the right or left. Since the twisted fiber bundle 3 contracts in the longitudinal direction, a cavity 5 is formed on the inner surface of the tip of the shaft tube.

In this state, a corresponding part of the hollow part 5 is drawn from the outside to form a shaft tip 6, an air hole 8 is made in the shaft tip, and the fiber bundle is impregnated with ink. 7 is pushed into the fiber bundle 3 through the shaft tip 6, the felt-tip pen is completed.

As described above, according to the method of the present invention, in the step of inserting the twisting tool 4 into the barrel 1 and twisting the fiber bundle 3, the fiber bundle shrinks and a cavity 5 is formed at the tip of the barrel. This makes it possible to draw the tip of the shaft, which was previously impossible with felt-tip pens in which the fiber bundle and barrel are extruded. Since the fiber bundle 3 has a small outer diameter, it does not block the air groove 2 on the inner surface of the shaft cylinder 1, and therefore, air circulation is excellent and the ink flow is smoothed.

Further, the rear end of the barrel of the felt-tip pen obtained according to the present invention may be closed as in the above embodiment, or may be closed with a tail plug as in a normal felt-tip pen, or it may be hardened into a fiber bundle 3 as shown in the third figure. It is also possible to infiltrate the tip of the fiber bundle with an agent and shave off the tip of the fiber bundle exposed from the barrel 1 to form the pen tip p for thick writing.

Note that the pen core 7 can be attached to the nib 6 by applying a solvent to the outside of the nib in advance to make it stick, or by making the nib a larger diameter and fitting tightly into the nib. I can do it.

[Brief explanation of the drawing]

The figures show examples; Fig. 1 is a partially longitudinal side view of a felt-tip pen obtained by a conventional method;
2A to 2D show the process of implementing the method of the present invention, A is a perspective view of the integrally molded shaft tube and fiber bundle, B is a vertical side view of the same, and C is a fiber bundle formed by a twisting tool. D is a longitudinal sectional side view of the main part showing the completed state of the felt-tip pen with a fine writing pen inserted into the tip of the shaft; FIG. 3 is another embodiment of the felt-tip pen obtained by the method of the present invention. FIG. 3 is a partially longitudinal side view showing an example. 1 is a shaft cylinder, 3 is a synthetic fiber bundle, 4 is a twisting tool, 5 is a hollow part, 6 is a shaft tip, and 7 is a pen core.

Claims (1)

[Claims] 1. A shaft cylinder with a synthetic fiber bundle provided inside is formed by extrusion molding, and a screwdriver-like twisting tool is inserted into the synthetic fiber bundle from the open end of the shaft cylinder and rotated to twist the shaft cylinder. A method for manufacturing a felt-tip pen, in which a hollow part is formed inside the tip part, a corresponding part of the hollow part is drawn from the outside to form a tip part, and a pen core is inserted into the tip part. .