JPH02303Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an improvement of a synthetic resin nib body used in writing instruments such as felt-tip pens and marking pens.

(Prior art) Most conventional synthetic resin pen nibs have a radial ink flow path in the center as a basic structure, but slight differences in the structure of the ink flow path may affect the writing feel and ink flow. Since writing conditions such as supply level may vary slightly, a large number of synthetic resin nib bodies with different structures have been proposed.

(Problem to be solved by the invention) The relationship between hardness and smoothness in the pen tip body seems to arise from contradictory factors in terms of writing feel. That is, the important factor that determines the smoothness is the hardness of the material constituting the nib body, and the structure of the nib body is added as a factor to this. As the hardness of the material of the nib body, that is, the synthetic resin (Delrin, polyester, etc.) increases, the smoothness of the pen becomes less smooth, resulting in a ``lumpy'' brush feel. If the hardness of the material is low, there will be problems such as wear and the appearance of directionality quickly, so it is necessary to have a hardness above a certain level.

This invention not only provides a good brush feel, but also has flexibility and elasticity with a moderate amount of stiffness.
Furthermore, the present invention provides a synthetic resin pen nib body that has repulsion elasticity and elastic recovery force that allow the stem rib to quickly return to its original position even if it is deformed by writing pressure.

(Means for Solving the Problem) In order to achieve the above object, the present invention provides a cylindrical composite in which the cross-sectional shape of the ink flow path formed in the axial direction is formed radially from the center. In the resin pen nib body, the ink flow path includes an annular member having a substantially circular cross-sectional shape that partitions the ink flow path from the outside, and a plurality of trunk-shaped members extending from the annular member toward the center and having a length that does not reach the center. The plurality of stem-like ribs are spaced apart from the radial ink flow path, which is arranged every other time and has a substantially triangular cross-sectional shape near its base. and a second stem-like rib that is thick near its base and becomes thinner toward the center, and has branch-like ribs on both sides thereof. A small rib protruding from the annular member is provided in the space defined by the trunk rib.

(Function) By adopting this configuration, the pen tip body of the present invention has flexibility and stiffness as a whole, and each stem-like rib has rebound elasticity, so the strength, tome, and splash peculiar to a brush are improved. I can write the characters I can.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a longitudinal sectional view of a writing instrument equipped with a synthetic resin nib body, in which 1 is a synthetic resin nib body, 2 is a shaft part, and 3 is a synthetic resin nib body 1 attached to a shaft part 2. 4 is a pad impregnated with ink, and 5 is a plug for sealing the rear end of the shaft.

FIG. 2 is an enlarged perspective view of the tip of the synthetic resin pen point body 1, and FIG. 3 is an enlarged cross-sectional view thereof.

The structure of the pen tip body will be explained with reference to FIGS. 2 and 3. The pen point body is obtained by extruding a molten synthetic resin through a die, so it has a cylindrical shape as a whole. An ink flow path 6 having a radial cross-sectional shape extends in the direction of the central axis of the pen tip body 1 . The ink flow path 6 is
The ink flow path 6 is defined by an annular member 7 having a substantially circular cross-sectional shape that partitions the ink flow path 6 from the outside, and a plurality of stem-like ribs 8 and 9 extending from the annular member 7 toward the center and having a length that does not reach the center. ing.

One of the first stem-like ribs 8 has a portion near its base.
It has a generally triangular space 8a in cross section, and this space 8a is separated from the radial ink flow path 6. A small rib 10 protruding from the annular member 7 is provided in the partitioned space 8a.
It is located in the center of the

The other second trunk-like rib 9 is thick near its base, becomes thinner toward the center, and branch-like ribs 9a and 9b protrude from both sides thereof.
Since the branch-like ribs 9b are shorter than the branch-like ribs 9a near the base, the cross-sectional shape of the stem-like ribs 9 is approximately triangular or chevron-shaped.

The tip of the stem-like rib 8 is located closer to the center than the tip of the other stem-like rib 9. In other words, the stem-like rib 8 is longer than the other stem-like rib 9. And they are arranged every other time. Moreover, these stem-like ribs 8 and 9 are
By setting appropriate intervals between the holes of the die during manufacturing, it is possible to form a surface with a circular cross-section in a connected state, thereby making it possible to form stem-like ribs 8,
The outer wall surface of No. 9 has many irregularities to retain ink.
It can contribute to guidance.

(Effects) Since the present invention has the above-described configuration, the first stem-like rib 8 having a substantially triangular space
The vicinity of the tip is more likely to bend than the space. However, when the writing pressure exceeds a predetermined level, the two walls that partition the approximately triangular space also deform and bend, but since the two walls are in tension with each other, they quickly return to their original positions.
This operation is due to the fact that the stem rib 8 has a free end. A second plate having branch-like ribs 9a and 9b.
The short branch-like ribs 9 are hard as a whole, but the area near the tip, that is, the one-third from the tip, is thinner and therefore more flexible than the base. The base of the stem-like rib 9 is "bark" and is therefore the part that is least likely to bend among the stem-like ribs, but once it bends, it has the strongest elastic recovery force.

Therefore, since the area near the center is softer than the area near the outer periphery, it is possible to obtain a firm and flexible writing feeling, and the approximately triangular space 8a of the stem rib 8 deforms when pressure is applied to the writing. , the action of returning to the original position in the removed state is repeated, and this action and capillary action give activity to the ink in the space 8a, and the ink flows along the radial ink flow path and the approximately triangular space 8a. Since the ink flows down and merges at the tip of the ink brush, it is excellent in terms of ink supply, and this also has the effect of assisting the sliding of the pen tip.

The branch-like ribs 9a, 9b and the small ribs 10 are provided to strengthen the capillary action of the ink flow paths in the vicinity of the respective ribs. In particular, in order to obtain flexibility and elastic recovery force, and to narrow the radial ink flow path located on the outside of the stem rib 8, the two walls of the stem rib 8 that partition the approximately triangular space 8a are made long. This weakens the capillary action of the space 8a, so it is extremely important to provide the small ribs 10.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a writing instrument equipped with a synthetic resin nib body, FIG. 2 is an enlarged perspective view of the nib body of the present invention, and FIG. 3 is an enlarged cross-sectional plan view thereof. 1... Pen tip body, 6... Radial ink flow path,
7... Annular member, 8, 9... Trunk rib, 8a...
Space, 9a, 9b... branch-like ribs, 10... small ribs.

Claims (1)

[Scope of utility model registration request] In a cylindrical synthetic resin pen nib body in which the cross-sectional shape of the ink flow path formed in the axial direction is formed radially from the center, the ink flow path has a cross section that partitions the ink flow path from the outside. It is partitioned by an annular member having a substantially circular surface shape and a plurality of stem-like ribs extending from the annular member toward the center and having a length that does not reach the center, and every other one of the plurality of stem-like ribs. A first stem-like rib having a space separated from the radial ink flow path having a cross-sectional shape and a substantially triangular shape near its base, and a first stem-like rib that is thick near its base and goes toward the center. and a second stem-like rib that is thin and has branch-like ribs on both sides thereof, and a small rib protruding from the annular member is provided in the space defined by the first stem-like rib. A synthetic resin nib body that is characterized by: