JPH025985Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention relates to the tail plug of a writing instrument, and more specifically, the present invention relates to a tail plug of a writing instrument, and more specifically, a tail plug fixed to the rear part of a metal barrel having an ink-impregnated batting inside. This invention relates to a tail plug for a writing instrument that is intended to reliably prevent ink from leaking.

(Prior Art) Conventionally, for example, writing instruments such as ballpoint pens and marking pens, which have fillings impregnated with water-based ink, refills thereof, and plotter pens (hereinafter referred to as writing instruments) have barrels made of metal. There is one formed in
Since the tail plug fixed to the rear of the metal barrel of these writing instruments is made of resin, the shape of the barrel and tail plug can change heat due to contraction and expansion of each of the barrel and tail plug due to temperature changes in certain environments. As a result, a small gap is created between the barrel and the tail plug, and as a result, there is often a problem that ink leaks from the tail plug side due to the capillary action.

Therefore, in an attempt to overcome these problems, several annular ribs are appropriately provided on the portion of the tail plug that fits into the rear inner wall surface of the shaft cylinder, or adhesive is used to increase the fixing strength. Attempts have been made to increase this, but satisfactory results have not yet been obtained.Furthermore, in recent years, the problem of ink leakage from the tail plug side has been caused by differences in deformation rates due to differences in materials. Based on this knowledge, there are also known models in which the shaft cylinder and tail plug are made of metal, but since both the shaft cylinder and tail plug do not exhibit soft elasticity, the dimensions of the inner and outer diameters of both are limited. In both cases, there remained room for improvement, as an extremely high degree of precision was required for the settings, which led to new problems such as increased costs.

(Purpose of the invention) This invention was created in view of the above circumstances,
Basically, the tail plug that is fixed to the rear part of the metal barrel is made of resin, but a metal support is inserted into the recessed hole inside the tail plug, thereby eliminating the problems of conventional writing instruments. The purpose is to provide a tail plug for the

(Structure of the invention) That is, the present invention provides a tail plug of a writing instrument that is fixed to the rear inner wall surface of a metal barrel having an ink-impregnated batting inside, and the tail plug is made of a resin material having a concave hole inside. The gist of this invention is a tail plug for a writing instrument, which is characterized by having a metal support fitted into the recessed hole.

Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings.

FIG. 1 shows the first embodiment of the present invention, and reference numeral 11 indicates a writing instrument shaft made of metal such as stainless steel or brass plated with various types of plating, and has a padding 12 impregnated with water-based ink or the like. A tail plug 13 made of a resin such as polypropylene or soft polyethylene is press-fitted into the rear inner wall surface of the writing instrument barrel 11, which is a cylinder. This tail plug 13 is
It has a recessed hole 14 inside, and inside the recessed hole 14 is a cylindrical metal plate made of stainless steel or brass plated with various types of plating, and has an outer diameter approximately equal to the diameter of the recessed hole 14. A support body 15 is fitted, and even if the tail plug 13 tries to deform due to temperature changes, this metal support body 15 is prevented, so that the writing instrument barrel 11 and the tail plug 13 are prevented from deforming. It is possible to prevent capillary action caused by a slight gap between the two, and at the same time, it is possible to eliminate ink leakage.

FIG. 2 shows a second embodiment of the present invention, which differs from the first embodiment in that one end face of a metal support 25 fitted into a recess 24 inside a resin tail plug 23 is shown in FIG. is located at a point that slightly protrudes from the end surface of the tail plug 23. This eliminates the need for the radial notch 16 at the inner end of the tail plug 13 as shown in FIG. This allows for proper air circulation.

FIG. 3 shows a third embodiment of the present invention, which differs from the first embodiment in that the metal support 35 fitted in the recessed hole 34 inside the resin tail plug 33 has a spherical shape. It differs from the example. As a result, in the case of this embodiment, since the metal support 35 has no directionality, the work of fitting the metal support 35 into the concave hole 34 of the tail plug 33 becomes very efficient.

Note that the shape of the metal support in the present invention is not limited to the above embodiments; for example, an appropriate number of notches may be provided at the inner end of the metal support,
The resin tail plug itself may have elasticity, as long as it has a shape that can prevent deformation due to temperature changes, and various forms may be used as long as the intended purpose is achieved. can be adopted.

(Effects of the invention) As described in detail above, the present invention provides a tail plug for a writing instrument that is fixed to the rear inner wall surface of a metal barrel having an ink-impregnated batting inside. It is made of resin with a concave hole, and a metal support is fitted into the concave hole, so the attachment part of the tail plug deforms due to environmental temperature changes, and this causes damage to the tail plug. It is possible to prevent ink leakage as much as possible, and when attaching the tail plug to the shaft cylinder, since the tail plug is made of resin, it has appropriate soft elasticity, so it can be used even if there is some deviation in the design dimensions. It exhibits excellent effects such as absorbing this and efficiently fixing it.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention.
Figures 2 and 3 are longitudinal sectional views of main parts of the writing instrument barrel in the first, second and third embodiments, respectively. 11, 21, 31... Writing instrument barrel, 12, 2
2, 32...Badding, 13,23,33...Tail plug,
14, 24, 34... recessed hole, 15, 25, 35...
...Metal support.

Claims (1)

[Scope of utility model registration request] In the tail plug of a writing instrument that is fixed to the rear inner wall surface of a metal barrel having an ink-impregnated batting inside, the tail plug is made of a resin having a recessed hole inside, and is a tail plug of a writing instrument characterized by having a metal support inserted therein.