JPH09267594A - Writing instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the generation of ink leakage even when an impact is applied by forming a weak capillary section without comb teeth in a temporary ink storage section of a temporary ink storage component and opening an air vent for the substitution of ink and air on the weak capillary section. SOLUTION: A temporary ink storage component 4 constituted of a pen point holder section 2 and a temporary ink storage section 3 is installed on the open side of a cylinder 1. A plurality of comb teeth 11 are formed as the temporary ink storage section 3, and slits 13 communicated with spaces 12 among respective comb teeth 11 and a central opening 10 are formed. A section of wide distance out of respective comb tooth 11 is formed as weak capillary section 15 in the temporary ink storage 3. An air flow passing opening 16 for the substitution of ink and air opened on the weak capillary section 15. The leakage of ink can be prevented by the arrangement even when the impact or the like is applied.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temporary ink reservoir having a comb-shaped temporary ink reservoir as a flow control member for supplying ink contained in an ink tank in a free state to a pen tip. And a writing instrument having the following.

[0002]

2. Description of the Related Art A writing instrument having a temporary ink reservoir having a temporary ink reservoir having a comb-shaped longitudinal section as a flow control member for supplying ink, which is freely contained in an ink tank, to a pen tip. Is known as a so-called raw ink type writing instrument, which can use an ink tank that stores a large amount of ink, can supply abundant ink to the pen tip, and is known to provide fresh handwriting. . However, since a large amount of ink is supplied to the nib, it is designed with great care in controlling ink leakage and ink shortage.

That is, a raw ink type writing instrument having a temporary ink reservoir member as an ink flow control member is a temporary ink reservoir member when the ink in the ink tank is supplied to the pen tip. The outside air is supplied into the ink tank through the space between the main body of the writing instrument to prevent the inside of the ink tank from becoming negative pressure. Therefore, the opening of the air hole communicating with the outside air is basically formed in the pen tip holder portion that substantially connects the temporary ink reservoir member and the writing instrument main body.

[0004]

The temporary ink reservoir member serves as a portion in which excess ink is temporarily retained in the inter-comb space of the comb-shaped section having a capillary force. Therefore, it is open to the space between the temporary ink reservoir member, which is a portion that supplies air into the ink tank, and the writing instrument body. That is, the ink accumulated in the space between the comb teeth of the temporary ink reservoir member is only retained by the capillary force, and is present in the portion open to the space communicating with the outside. Therefore, when an impact is applied to the writing instrument itself, the ink temporarily stored in the temporary ink reservoir member is easily scattered in the space communicating with the outside world.
There is a problem that the scattered ink adheres to the inner wall of the main body of the writing instrument and appears as an ink leak to the outside through the space where air communicates.

[0005]

That is, according to the present invention, a temporary ink reservoir having a comb-shaped longitudinal section is provided as a flow control member for supplying ink, which is freely contained in an ink tank, to a pen tip. In a writing instrument having a temporary ink reservoir member, a weak capillary force portion having no comb teeth is formed in the temporary ink reservoir portion of the temporary ink reservoir member, and ink-air displacement is performed in the weak capillary force portion. The gist is a writing instrument characterized in that a ventilation hole for is opened.

[0006]

First, the air passage for supplying air to the ink tank is designed so as not to directly communicate with the opening of the air flow passage. That is, the temporary ink reservoir member is formed in the middle portion thereof and opened in a portion where ink hardly exists. This is the reason why this portion is used as a weak capillary force portion without forming comb teeth that exert a capillary force. Originally, it is preferable to set the portion having no capillary force at all, but since it is not practical, the weak capillary force portion is used. Also, this weak capillary force section is also connected to the temporary ink reservoir by a slit so that even if ink gets in, the ink will quickly move to other temporary ink reservoirs and will not reach the air circulation holes. is there.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
The one shown in FIG. 1 is an example of a refill of a so-called writing instrument that is used by being stored in an exterior body (not shown). A temporary ink reservoir member 4 including a pen tip holder portion 2 and a temporary ink reservoir portion 3 is attached to the opening side of a metal bottomed cylindrical body 1 containing ink in a free state, and the bottom side is an ink tank. A ballpoint pen tip 7 is attached to the pen tip holder portion 2 of the temporary ink reservoir member 4 via a joint pipe 6 as a portion 5. The temporary ink reservoir member 4 is fixed by being fitted into the inner-cover protrusion 8 whose diameter is reduced by the plastic deformation of the bottomed tubular body 1 made of metal. Further, the ink relay core 9 made of a fiber bundle reaches the ink tank portion 5 from the inner hole of the ballpoint pen tip 7 through the central hole 10 of the temporary ink reservoir member 4.

The temporary ink reservoir member 4 has a plurality of comb teeth 11 as the temporary ink reservoir portion 3, and a slit 13 communicating with the space 12 between the comb teeth and the central hole 10 is formed. When pressure is applied to the ink tank portion 5 due to temperature change or the like, excess ink pushed out by the pressure is not supplied to the ballpoint pen tip 7 via the ink relay core 9 and passes through the slit 13 to the space 12 between the comb teeth 11. It is temporarily stored.

In addition to the slit 13, an air circulation groove 14 for supplying air into the volumetric ink tank portion 5 of the ink used for writing is formed in communication with the space 12 between the comb teeth. ing. The air circulation groove 14 is different from the slit 13 which is a moving portion of the ink between the space 12 between the comb teeth and the ink tank portion 5, and is a space in which the capillary force is hard to work, and the presence of ink does not hinder the circulation of air. It is done like this.

In the case of this example, a water-based pigment ink having a viscosity of 10 cps or less and a surface tension of about 20 to 50 dyn / cm and a temporary ink reservoir member 4 made of acrylonitrile butadiene styrene are used, and the ink for the temporary ink reservoir member 4 is used. Has a contact angle of about 20 ° to 50 °, and the distance between the comb teeth 11 (width of the space 12) and the width of the slit 13 are 0.1 mm to, considering the ink holding ability by the capillary force.
It is set to about 0.5 mm.

As shown in FIG. 2, which is an enlarged view of the portion I of FIG. 1, in the temporary ink reservoir 3 in which the comb teeth 11 are formed, the portion where the distance between the comb teeth 11 is wide is a weak capillary portion. 1
Formed as 5. The weak capillary tube portion 15 has almost no ink holding ability as compared with the other inter-comb space 12 and the slit 13, and is a portion in which ink is relatively hard to exist. By the way, in this example, the width of the weak capillary portion 15 is set to 1.0 mm. In addition, as shown in FIG. 3 which is a cross-sectional view taken along the line AA of FIG.
An air circulation hole 16 is opened at the tip of the pen tip holder 2. The opening portion at the tip of the pen tip holder portion 2 of the air flow passage 14 is opened over the entire circumference of the joint pipe 6.

Such a writing instrument is usually used in such a form that the pen tip is on the bottom and the ink tank part is on the top. As described above, excess ink when pressure is applied to the ink tank portion 5 is stored in the inter-tooth space 12 through the slit 13.

At this time, when an impact is applied, the ink stored in the inter-comb space 12 is scattered and adheres to the inner wall 1a of the bottomed cylindrical body 1. Since the ink attached to the inner wall 1a is not regulated, it will be transmitted to the inner wall 1a and fall to the pen tip side by attractive force. The opening, which is the most pen tip side portion of the bottomed tubular body 1, is sealed by the pen tip holder portion 3 so that ink does not leak out from here.

The weak capillary portion 15 is not formed at the pen tip side portion of the temporary ink reservoir 3 which is the portion corresponding to the opening of the bottomed cylinder 1. This is because if it is formed in this portion, it will be attacked by the ink adhering to the inner wall 1a. Therefore, the inter-comb space 12 is formed at the most pen tip side portion of the temporary ink reservoir 3, and even if the ink adhering to the inner wall 1a reaches the vicinity of the opening of the bottomed cylinder 1, it is positioned at that portion. The inter-comb space 12 and the slits 13 are taken in. That is, the air circulation hole 16 does not enter the weak capillary portion 15 having the opening, and the air circulation hole 16 does not enter.
The occurrence of ink leakage is suppressed as much as possible.

Another example is shown in FIGS. Although the basic structure is the same as the above-described example, ink leakage is further suppressed by devising the positional relationship between the air circulation hole 16 that is open to the outside and the air circulation groove 14 and the slit 13 that supply air to the ink tank portion 5. This is an example. That is, as shown in FIG. 5 which is a view taken along the line B-B and FIG. 6 which is a view taken along the line C-C, a slit 13 having a relatively strong capillary force is opened in the air circulation hole 16, and the capillary force is increased. The weaker air circulation groove 14 is positioned farthest from the air circulation hole 16. The ink attached to the inner wall of the cylinder 1 due to an impact or the like can move to the pen tip side due to gravity, but at this time, the air circulation groove 14 is a space having a weak capillary force and little ability to hold the ink, so the inner wall The ink adhering to is easily moved through this air circulation groove 14 portion. Normally, the weak capillary portion 15 and the slit 13 that open the air circulation hole 16 prevent the ink from reaching the air circulation hole 16, but when further impact or centrifugal force is applied, the air circulation groove 14 is formed. There is a possibility that the ink that has passed through will move to the air circulation hole 16. Therefore, even if the ink that has passed through the air circulation groove 14 reaches the weak capillary portion 15 where the air circulation hole 16 opens, there is a distance until it reaches the air circulation hole 16 and ink leakage is suppressed accordingly. It is possible. In FIG. 4, the slit 13 and the air circulation groove 14 are not shown, but they are shown by broken lines. The left side of the drawing is a broken line showing the slit 13, and the right side of the drawing is a broken line showing the air circulation groove 14.

Another example is shown in FIGS. 7 and 8, and is a cross-sectional view corresponding to FIGS. 5 and 6 described above. In this example, the ink adhering to the wall surface of the cylinder 1 does not reach the weak capillary portion 15 where the air circulation hole 16 opens even if the ink attached to the wall surface of the cylinder 1 reaches the air circulation groove 14 without impairing the air circulation function of the air circulation groove 14. This is one example. That is, the air circulation groove 14 and the slit 13 are formed at the same position and communicate with each other. Therefore, even if the ink reaches the air circulation groove 14, the ink can be collected in the slit, which is a portion having a relatively strong capillary force.

In addition to the above, various modifications can be made without departing from the gist of the present invention. For example, in the illustrated example, the refill having the ballpoint pen nib is shown, but it is also possible to use it as a writing instrument by itself without using an exterior body, and as a pen nib, a felt pen, a continuous porosity may be used. It may be a synthetic resin pen tip or the like. Further, the bottomed cylindrical body 1 may be a molded product of synthetic resin in addition to metal, and a tail plug may be attached to the rear end portion. Examples of the temporary ink reservoir member 4 include acrylonitrile styrene, acrylonitrile styrene, styrene, polyoxymethylene, and the like, and surface treatment such as ink-philic treatment may be performed in consideration of wettability with ink.
Further, in forming the weak capillary portion 15, in addition to forming a wide portion between the comb teeth, the surface treatment of the ink-forming portion is partially performed, and the surface shape of the portion is a mirror surface as compared with the peripheral portion. You can also do so.

[0018]

As described above, the writing instrument of the present invention is a raw ink type writing instrument which employs a temporary ink reservoir member having a comb-shaped cross section, but is unlikely to cause ink leakage even when an impact is applied. is there.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment.

FIG. 2 is an enlarged view of a portion I in FIG.

FIG. 3 is a sectional view taken along the line AA of FIG.

FIG. 4 is an enlarged cross-sectional view of an essential part showing another embodiment.

5 is a cross-sectional view taken along the line BB of FIG.

6 is a sectional view taken along the line CC in FIG.

FIG. 7 is a view corresponding to FIG. 5 showing still another embodiment.

FIG. 8 is a view corresponding to FIG. 6 of the embodiment shown in FIG.

[Explanation of Codes] 1 cylinder 1a inner wall 2 pen tip holder part 3 temporary ink reservoir part 4 temporary ink reservoir member 5 ink tank part 6 joint pipe 7 ballpoint pen tip 8 inner wrapping protrusion 9 ink relay core 10 center hole 11 comb Tooth 12 Space 13 Slit 14 Air circulation groove 15 Weak capillary 16 Air circulation hole

Claims (1)

[Claims] 1. A writing instrument comprising a temporary ink reservoir having a comb-shaped temporary ink reservoir as a flow control member for supplying ink, which is freely contained in an ink tank, to a pen tip. In the temporary ink reservoir member, a weak capillary force portion having no comb teeth is formed in the temporary ink reservoir portion, and the weak capillary force portion has ink.
A writing instrument having a vent hole for air replacement.