JPS627512Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to the improvement of a ballpoint pen nib in which a ball is held at the tip of a thin tube so as to be able to roll freely. The purpose is to obtain a suitable high-quality ballpoint pen nib.

Conventionally, such ballpoint pen nibs have been used, for example, in 1973.
-42566, etc., a ball is held at the tip of a capillary so that it can roll freely, and a wire made of metal such as stainless steel or synthetic resin is inserted into the capillary, and the outer periphery of the capillary is caulked inward at multiple locations to secure the wire. A structure is known in which a pen tip is fixed at a central position within a thin tube, and the pen tip is communicated with an ink cylinder via a holder, an ink guide mechanism, and the like. However, a pen nib with such a structure has a drawback that it is difficult to use it as a nib for fine characters, especially when the writing line width is about 0.2 to 0.6.

In other words, when making a pen nib for fine characters, for example, when making a pen with a writing line width of 0.3 m/m, the outer diameter of the thin tube is 0.8
~1.5m/m, inner diameter 0.7~1.4m/m, length 4.0~7.0
m/m, ball diameter 0.3 to 0.5 m/m, and wire rod outer diameter 0.6 to 1.3 m/m, making parts extremely small and requiring higher precision in parts and assembly. This structure has a large number of small parts connected to each other, so there are many joints, which requires a lot of effort to assemble, resulting in poor productivity.In addition, high precision cannot be achieved in the product, resulting in large variations in quality. There are drawbacks.

In addition, there is a drawback that the wire rod moves due to an impact such as a fall, resulting in poor contact at the bonded portion, which may cause defects such as running out of ink or making it impossible to write.

The present invention eliminates such drawbacks.

Examples will be described in detail below.

FIG. 1 is an assembled vertical sectional view of a ballpoint pen using the pen tip of the embodiment of the present invention.

Reference numeral 1 denotes a shaft cylinder, and the shaft cylinder 1 houses an ink storage body 2 made of a fiber bundle or the like in which ink is stored. Further, a tail plug 3 is fitted to the end of the barrel 1, and a pen tip A is fitted and fixed into the fitting hole 4 at the tip.

Reference numeral 5 designates an ink guiding core made of a resin-processed fiber bundle or a sintered body of synthetic resin, with one end inserted into the pen nib A and the other end inserted into the ink storage body 2, and the ink is absorbed into the ink storage body 2 by capillary action. The pen tip A is configured to suck the ink and lead it to the pen tip A.

The pen tip A consists of a ball 6, a thin tube 7 made of metal such as stainless steel, polyacetal resin, etc., and an ink guide member 8.

The ink guide member 8 is made of synthetic resin such as polyacetal or polycarbonate, and has a small diameter ink guide rod part 9 and a large diameter holding part 10 coaxially integrally molded. The tip of the ink guide rod 9 is recessed to form a ball seat 11, and the cross-sectional view 90
An axial V-shaped groove 12 communicating with the ball seat 11 is formed in the ° direction.

Then, a thin tube 7 whose inner diameter is approximately equal to the outer diameter of the guide rod portion 9 is press-fitted and fixed to the ink guide rod portion 9, and a ball 6 is inserted between the inner caulked portion 7' at the tip of the thin tube 7 and the ball seat 11. The space between the non-contact surface between the outer peripheral surface of the guide rod 9 and the inner peripheral surface of the thin tube 7, that is, the V-shaped groove 12, is the ball 6.
The ink guide gap 13 is in communication with the ink guide gap 13.

Reference numeral 14 indicates an ink guiding hole opened in the axial direction of the holding part 10, and the upper end of the ink guiding hole 14 communicates with the ink circulation gap 13, and the lower end communicates with the holding part 1.
A holding hole 16 formed for mounting and fixing an ink guide core 5 having an annular stepped portion 15 formed at the lower part of the ink guide core 5.
is connected to.

Reference numeral 17 denotes an ink reservoir formed between the inner end of the holding hole and the guide core 5. Incidentally, the ink reservoir 17 may be omitted, or the ink cylinder may be directly attached to the holding hole 16. Therefore, when writing, the ink stored in the occluding body 2 is led out to the ball seat 11 through the guide wick 5, the ink reservoir 17, the ink guide hole 14, and the ink guide gap 13 by capillary action, and by the rolling of the ball 6. I can write.

Particularly in this embodiment, since the ink guide gap 13 communicates with the outer circumference of the ball seat 11, the ink can be drawn out very smoothly and there is no risk of blurring even during high-speed writing.

The guide gap may be formed by forming a large number of slit-like grooves in the axial direction of the guide rod portion 9 using the ink or the like used, and forming a large number of narrow slit-like grooves, or by forming a large number of narrow slit-like grooves.
As shown in the figure, an appropriate structure can be adopted, such as forming the guide rod part 109 into a columnar shape with a small diameter to form an annular guide gap 113.

To assemble this pen nib A, for example, place the ball 6 with the thin tube 7 forming the tip caulked part 7 facing downward.
It is very easy to assemble by simply inserting the guide rod 9 of the ink guide member 8 into the thin tube 7 and then press-fitting the guide rod part 9 of the ink guide member 8 into the thin tube 7 until the ball 6 is clamped and fixed in a rotatable manner between the caulked part 7' and the ball seat 11. I can do it.

Note that the method of fixing the thin tube and the ink guide member is other than press fitting, as shown in FIG.
8 and fixed by caulking portion 118', or by bonding with instant adhesive. Also, when assembling the ballpoint pen, use the pen tip A.
Since it is possible to construct an integrated product in which the ink guiding core 5 or the ink cylinder is attached to the holding hole 16 of
It can be easily assembled by simply attaching and fixing the holding portion of the pen tip to the barrel. Since the present invention is constructed as described above, it can be assembled extremely easily.

Furthermore, since an ink guide member in which the ink guide rod and the holding part are integrally formed is used, there are fewer parts and fewer connecting parts. In addition, the ink guide member can be mass-produced by injection molding of synthetic resin, and high dimensional accuracy can be obtained, making it particularly suitable for fine point pen nibs that require high precision. Obtainable.

[Brief explanation of the drawing]

Fig. 1, sectional view of a ballpoint pen using the pen nib of the embodiment, Fig. 2, sectional view of the main part of the embodiment, Fig. 3,
Fig. 2 a-a sectional view, Fig. 4, Fig. 2 b-b sectional view, Fig. 5, Fig. 2 c-c sectional view, Fig. 6, other embodiment sectional views, Fig. 7, FIG. 6 dd sectional view. A... Pen tip, 6... Ball, 7... Thin tube,
8,108... Ink guide member, 9,109...
Ink guiding rod part, 10, 110...holding part, 1
3,113... Ink guide gap, 14,114...
...Ink guiding hole.

Claims (1)

[Scope of utility model registration request] In a ballpoint pen nib in which a ball is rotatably held at the tip of a thin tube, the ink guiding member is made of integrally molded synthetic resin and has a small diameter ink guiding rod part and a large diameter holding part connected in the axial direction. An ink guiding rod is inserted into the thin tube, and an ink guiding gap that communicates with the ball is formed between the outer peripheral surface of the ink guiding rod and the inner peripheral surface of the thin tube, and the gap is formed in the axial direction of the holding portion. 1. A ballpoint pen nib, characterized in that an ink guide hole communicating with the ink guide hole and a holding hole into which an ink guide core or an ink cylinder is attached and fixed are opened, and the thin tube is fixed to the ink guide member by appropriate means.