JPH09150595A - Synthetic resin nib - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inhibit the occurrence of a trouble that writing can not be conducted due to clogging of an ink passage, by a method wherein the length of a small-diameter part in the longitudinal direction is made larger than that of a slit in the longitudinal direction. SOLUTION: The fore end part of a pen is a small-diameter part 3 formed by shaving off a covering part 2 and a slit 4 is formed in a part about 1/2 of this small-diameter part from the fore end thereof. The slit 4 is formed by immersing the fore end part in a swelling liquid for a material of a pen. When the fore end part of the pen is immersed in the swelling liquid, in other words, an opening part of an ink passage 1 is expanded due to swelling of the fore end part, a wall part forming the ink passage 1 is thereby split and the slit 4 is formed. When the fore end part of the pen is worn with writing and the small-diameter part 3 becomes short, the position of a support point of a writing load shifts therewith and a split length of the slit 4 increases as well. In this way, the length of the slit 4 is maintained in a certain degree and a function of removing dust is prevented from lowering with passage of time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises a small-diameter portion and a large-diameter portion, and the tip of the small-diameter portion is a writing portion in which an ink passage is opened, and a slit communicating with the ink passage is formed in the writing portion. The present invention relates to a synthetic resin nib.

[0002]

2. Description of the Related Art Conventionally, polyethylene, polypropylene,
Synthetic resin nibs made by extrusion molding methods such as polyacetal, polyamide, and polyether ether ketone have longitudinal communication holes that are ink passages, but the ink passages are used for writing on the writing surface such as paper. There was a problem that dust from the writing surface, fiber dust from the paper, abrasion dust from the synthetic resin nib itself, etc. clogging the ink passages and obstructing the ink ejection to form handwriting by abutting. .
For this reason, a slit is formed in the tip writing portion of the synthetic resin pen tip, and when writing, dust or debris that has entered the ink passage is discharged by utilizing the opening and closing of the slit by writing pressure.

An example is as shown in FIG. 3, in which an ink passage 101 is formed of a polyoxymethylene resin inside, and a polyoxymethylene covering portion 201 for maintaining strength is integrally formed outside. Is covered. The tip portion is polished in a tapered shape, and a slit 401 is formed as a small-diameter portion 301 up to a portion where the covering portion 201 is scraped away.

[0004]

The synthetic resin nib is
In the first place, since the material is softer than metal or the like, a soft writing feeling can be obtained, but due to the soft material, it was more easily worn than metal. That is, the writing part is worn away as the user writes. When the writing part becomes worn and the synthetic resin nib becomes shorter, the slit becomes shorter, and the function of discharging the dust and debris that entered the ink passage with the ink is not exerted, and the ink passage becomes clogged and writing becomes impossible. There was a problem that it could not be suppressed.

[0005]

[Means for Solving the Problem] That is, a writing portion having a small-diameter portion and a large-diameter portion, the tip of the small-diameter portion having an ink passage open, is formed with a slit communicating with the ink passage. In the synthetic resin nib, the length of the small diameter portion in the longitudinal direction is made longer than the length of the slit in the longitudinal direction.

[0006]

The synthetic resin pen tip of the present invention uses the change of the writing pressure applied to the writing part due to the shortening of the pen tip itself due to abrasion, and by changing the notch end point position of the slit, The function of removing dust and debris from the slit does not deteriorate with time. The notch end point position of the slit is formed on the tip side of the step portion which is the boundary portion between the small diameter portion and the large diameter portion of the synthetic resin pen tip consisting of the small diameter portion and the large diameter portion. When the length of the small diameter portion in the longitudinal direction is shortened due to abrasion, the writing pressure per unit volume applied to the small diameter portion increases, the slit tears to absorb this writing pressure, and the notch end point position moves. Therefore, the length of the slit is maintained to some extent, and the action of removing dust and debris does not decrease over time.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
FIG. 1 is a sectional view of a synthetic resin nib of the present invention, and FIG.
FIG. 2 is a view from the direction I of FIG. 1, in which a polyoxymethylene resin is extruded and then stretched to obtain a rod having an ink passage 1 formed therein, and a polyoxymethylene resin coating portion 2 for maintaining strength is provided outside. It is covered and integrally formed.

The tip portion is a small-diameter portion 3 which is ground by polishing with a polishing stone or the like to form a small-diameter portion 3.
The slit 4 is formed up to about 2 portions. The slit 4 can be formed by immersing the tip in a swelling liquid for the material of the pen tip. That is, when the tip of the pen tip is dipped in the swelling liquid, the tip swells and the opening of the ink passage 1 expands. As a result, the meat portion forming the ink passage 1 is torn and the slit 4 is formed.
In order to control the length of the slit 4 to be torn, it can be controlled to some extent by controlling the time, temperature, etc. for immersing in the swelling liquid.

As the tip of the pen tip wears and the small-diameter portion 3 becomes shorter as the user writes, the position of the fulcrum with respect to the writing load also moves, and the crack length of the slit 4 also advances. Therefore, the length of the slit 4 is maintained to some extent, and the action of removing dust and debris does not decrease over time.

In addition to the above, various modifications can be made without departing from the gist of the present invention. For example, in the above example, the pen tip member has a flat plate shape as a whole, but may have a circular or elliptical cross section. Further, a plurality of slits may be formed according to the opening area of the ink passage, or the slits may intersect with each other. Further, the writing instrument for connecting the synthetic resin nib of the present invention may be a so-called raw ink type writing instrument that accommodates ink in a free state, or a so-called batting type writing instrument in which a fiber bundle is impregnated with ink. . Further, the resin used as the pen tip can be colored with an ink color or the like.

[0011]

EFFECT OF THE INVENTION A comparative writing test was conducted between the synthetic resin nib of the present invention shown in FIG. 1 and the conventional synthetic resin nib shown in FIG. The resulting graph is shown in FIG. The solid line in the graph indicates the synthetic resin nib of the present invention shown in FIG. 1, and the broken line indicates the conventional synthetic resin nib shown in FIG. . With a spiral writing tester, writing angle 60 °, writing speed 7 cm / sec, writing load 1
Spiral writing was done at 50 g using an aqueous dye ink (viscosity 2.7 cps). The horizontal axis represents the writing distance, and the vertical axis represents the ink discharge amount per 100 m writing. This graph also shows that the synthetic resin pen tip of the present invention can write a long distance with a stable ink discharge amount.

From the above, the synthetic resin nib of the present invention is
Since the action of removing dust and debris does not decrease over time, stable long-distance writing can be realized.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment.

FIG. 2 is a view on arrow I in FIG.

FIG. 3 is a sectional view showing a conventional example.

FIG. 4 is a line graph showing the results of a writing test.

[Explanation of symbols]

 1 Ink passage 2 Cover part 3 Small diameter part 4 Slit

Claims (1)

[Claims] 1. A synthetic resin pen tip comprising a small diameter portion and a large diameter portion, the writing end portion of which has an ink passage opening at the tip of the small diameter portion, and a slit communicating with the ink passage is formed in the writing portion. The synthetic resin nib, wherein the length of the small diameter portion in the longitudinal direction is longer than the length of the slit in the longitudinal direction.