JPS6136383Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a neck mounting structure for a writing instrument in which the protrusion length of the pen tip that protrudes from an axially movable cap screwed onto the tip of a barrel can be adjusted.

Conventionally, a pen nib that is fitted into a cap is made to protrude from the base of the cap and comes into contact with an ink storage body, and the cap is screwed onto the tip of a barrel so that it can move in the axial direction, so that the pen nib can be protruded from the cap. A writing instrument in which the protruding length of the tip can be adjusted is well known (see, for example, Japanese Utility Model Application Publication No. 179248/1983).

According to this well-known example, since the base is screwed onto a part of the shaft cylinder (member 12), there is a disadvantage that, when mass-produced, variations occur in the screwed portion. In other words, the threaded joint between the cap and part of the shaft cylinder often becomes looser or tighter for each product when mass-produced. It is difficult to obtain a product with a tight threading degree, and if the threading thread is loose, looseness will occur in the threaded part, causing the pen tip to become curved and obstructing the flow of ink, and making writing difficult. There is a problem in that it is difficult to easily and finely adjust the ejection length of the pen tip by moving the cap smoothly in the axial direction, and a solution to this problem is desired.

This invention is proposed to solve the problem of tight screw threads among these problems.
When the neck seat is screwed onto the barrel, either one or both of the neck seat threaded part and the barrel barrel threaded part are configured to be deformable, so that the tight threaded part can be loosened to some extent, so that the neck seat can be tightened. Smooth axial movement,
To provide a writing instrument equipped with a useful neck mounting structure that allows easy fine adjustment of the protruding length of a pen tip.

To explain the embodiment with reference to the drawings, FIGS. 1, 2, and 3 show structural examples in which the shaft cylinder threaded portion 301 of the shaft cylinder 3 can be deformed.

The neck seat 1 is equipped with a thin tube 102 that can be projected from the tip separately or in the same body as necessary, and has a shaft tube 3 at the base.
A neck threaded portion 101 for threading onto the shaft cylinder threaded portion 301 is integrally provided in a protruding manner. The neck seat screwing part 101 has a cylindrical cross section, and a deformed screw 103 is provided on the outer circumferential surface, and this screw is screwed into the normal thread 302 of the shaft cylinder screwing part 301. The irregularly shaped screw 103 has three threads at appropriate intervals in the circumferential direction, as shown in FIG.
The outer circumferential surface of the neck threaded portion 101 protrudes at certain points, and is configured so that the outer circumferential surface of the neck threaded portion 101 becomes the root of the root. to slightly deform it in the cylindrical direction. A pen point 2 passes through the neck seat 1, and the base of the pen point protrudes from the pen point through hole of the neck seat 1 and is connected to the tip of an ink guiding core 4 fixed in the barrel cylinder 3.

If the base of the nib 2 is connected and fixed to the tip of the ink guiding core 4, there is no need to provide a nib holding structure in the nib through hole of the neck seat 1. The shaft cylinder threaded part 301 of the shaft cylinder 3 is constructed with a thin wall, and a normal thread 302 with a low thread is provided on the inner circumferential surface, and when the irregularly shaped screw 103 of the neck threaded part 101 is screwed, three places of this irregularly shaped screw are formed. The shaft-tube threaded portion 301 is compressed by the screw thread and deformed to some extent in the circumferential direction, and the tight threading is loosened to some extent to achieve a comfortable and moderate threading.

As described above, the irregularly shaped screw 10 has three threads formed on the outer circumferential surface of the neck threaded portion 101 of the neck seat 1.
3 is provided, and one side is a thin shaft cylinder threaded part 301 of the shaft cylinder 3.
A normal screw 302 with a low thread is provided on the inner peripheral surface,
When the irregularly shaped screw 103 is screwed into this regular screw, only three threads of this irregularly shaped screw are screwed together, so the contact area between both screws 103 and 302 is reduced, and the configuration with a tight screwing degree is somewhat difficult. Due to the three threads of the irregularly shaped screw 103 that is easily loosened and is screwed into the regular screw 302 with low threads, the shaft cylinder threaded portion 301 is compressed in the circumferential direction and deformed to some extent, causing both screws to loosen. The contact area between 103 and 302 is reduced, and the tightly screwed structure is changed to a structure that is more or less easily loosened. Therefore, even if the neck seat threaded portion 101 and the shaft cylinder threaded portion 301 have a slight dimensional error that would result in a tight configuration, the screws may loosen to some extent. The degree of screw engagement is appropriate, and the neck seat 1 can be moved smoothly in the axial direction, and the screwed portion can be configured without play.

The pen tip 2 in this example has a structure that can be removed or replaced.

As described above, the present invention is a writing instrument configured to move the cap screwed onto the tip of the shaft cylinder in the axial direction to adjust the protruding length of the pen tip that protrudes from the cap. Since the outer circumferential surface of the protruding neck threaded part is made up of an irregularly shaped screw with threads formed at multiple locations at appropriate intervals in the circumferential direction, there is a slight dimensional error that results in a tight configuration. Even if the neck threaded part and the shaft cylinder threaded part are screwed together, if one or both of them are deformed due to mutual screwing, it will become a little looser, and the threaded part will reach an appropriate degree, and the neck part will become loose. can be moved smoothly in the axial direction, and the protruding length of the pen tip can be easily and easily finely adjusted. At the same time, play occurs in the threaded part between the neck seat threaded part and the barrel barrel threaded part. It is possible to eliminate the concerns, eliminate defects that make it difficult to write, provide a useful writing instrument, and achieve the intended purpose.

[Brief explanation of the drawing]

FIG. 1 is a partially vertical front view showing the mounting structure of the present invention, FIG. 2 is a cross-sectional view taken along the - line in FIG. 1, and FIG. 3 is a partially vertical side view. In the figure, 1 is the neck seat, 101 is the neck threaded part, 103
2 is an irregularly shaped screw, 2 is a pen tip, 3 is a barrel, and 301 is a barrel threaded portion.

Claims (1)

[Scope of utility model registration request] The pen tip fitted into the cap is made to protrude from the base of the cap, and the cap is screwed onto the tip of the barrel so that it can move in the axial direction, making it possible to adjust the protruding length of the tip of the pen tip that protrudes from the cap. In the writing instrument constructed above, the neck seat mounting structure comprises an irregularly shaped screw having threads formed at a plurality of locations at appropriate intervals in the circumferential direction on the outer circumferential surface of the neck seat threaded portion protruding from the neck seat.