JPS6345333Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention was made with the aim of controlling the quality variation of a small tube type writing instrument in which the pen tip is composed of a small tube and a rod that is slidably arranged inside the small tube. It is something.

Among the small-tube type writing instruments having the above-mentioned type of nib, it is known that the sliding force is applied to the rod by an elastic liquid-containing material such as urethane foam placed behind the rod. . The liquid-containing member also plays the role of discharging ink and can be positioned as an ink conductor, and by using this member, extremely good handwriting can be obtained.

However, the use of elastic members has the disadvantage that it tends to cause variations in quality, especially variations in the sliding force applied to the rod. This drawback is
Because the member (hereinafter referred to as an ink conductor) has elasticity, it tends to cause variations in molding dimensions, and it is also difficult to align the member when it is placed behind the rod. Considering that the sliding force also serves as the driving force to release the dirt that has entered the small tube, it is recognized that this problem is an important point that should be improved.

The present invention has been made in view of the above points. Hereinafter, an embodiment of the present invention will be explained based on the attached drawings. In FIG. 1, reference numeral 1 is a tip attached to the tip of a shaft tube (not shown), and a small tube 2 is attached to the tip of this tip 1. It is supported protrudingly. Since it is desirable that the small tube 2 has excellent abrasion resistance, FIG. 1 shows a tubular body 2a made of stainless steel, for example, with a protruding piece 2b made of ceramic, for example, attached to the tip. A rod 3 is slidably disposed within the small tube 2, and its rear end 3a is supported by an ink conductor 4 inserted into a large diameter hole 1a of the tip 1. The rear part of the ink conductor 4 is connected to an ink storage body made of batting or the like housed in a shaft cylinder (not shown) or to a comb-like ink reservoir member (so-called bellows) in a raw ink type writing instrument, and ink flows from these members. The ink is supplied to the writing surface through the ink conductor 4 and the gap between the rod 3 and the small tube 2.

In the above, the ink conductor 4 is the key point of the present invention. This ink conductor 4 is made of a material that has substantially no elasticity before assembly and does not come into contact with ink. Examples of the material include polyvinyl alcohol formalized and foamed, and elastic urethane having open pores impregnated with polyvinyl alcohol without crushing the pores and then formalized.

Therefore, regardless of whether the ink conductor 4 is formed by cutting, punching, etc., or regardless of the desired shape after forming, the ink conductor 4 can be easily obtained with less variation in dimensions. . Furthermore, since the tip 1 has no elasticity when inserted into the tip 1, that is, it is "hard," it is difficult to achieve good positioning accuracy by inserting the rod 3 to its most advanced position or to a predetermined position. can. Furthermore, the ink conductor 4 can be fixed by press-fitting or using adhesive.
``Hardness'' is also useful for fixing the tip 1 to the tip 1. Regarding the "press fit" mentioned here, it is sometimes possible to utilize the force of swelling of the ink conductor 4 when ink is introduced into the ink conductor 4 after assembly.

As mentioned above, since the ink conductor 4 is "hard" with virtually no elasticity before it comes into contact with ink, various precisions such as forming and positioning can be improved, and as a result, assembled,
When ink is guided and the ink conductor 4 exhibits elasticity and acts as a sliding member against the rod 2, it can fully exert its sliding force, and
The practical effects of the present invention are extremely large, such as fewer defective products even in mass production.

However, within the scope of the gist of this invention,
Various modifications are possible, such as providing a locking step for positioning the ink conductor 4 in the large diameter hole 1a of the chip 1 in FIG. The front member, which is fully inserted into the chip 1, is used as a sliding member for the rod, and the rear member is a fiber bundle, a resin sintered body, or a general material made by resin extrusion. It can also be used as an ink conducting member.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a main part showing an embodiment of the present invention. 1...chip, 2...tubule, 3...rod, 4...
...Ink conductor.

Claims (1)

[Scope of utility model registration request] A pen tip is constituted by a small tube and a rod that is slidably disposed within the small tube, and a sliding force is applied to the rod by an elastic ink conductor that is placed behind the rod. A small tube type writing instrument characterized in that the ink conductor has no elasticity before assembly, that is, in a state where it does not come into contact with ink.