JPH1178352A - Direct liquid type writing utensil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid an ink leakage trouble and, at the same time, suppress the production cost of a writing utensil through a simple structure. SOLUTION: In this writing utensil, an ink absorber 4 made of porous material is arranged between a penpoint 2 and an ink tank 3. In the ink absorber 4, an ink retaining part 5 (a taperingly compressed part), in which the capillary force becomes gradually stronger from the front part of the ink absorber to its rear part, is provided. At the rear end of the ink retaining part 5, a liquid densified part 6 (a straightly compressed part), the capillary force of which is stronger than that in the ink retaining part 5, is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a direct liquid writing instrument. More specifically, the present invention relates to a direct liquid writing instrument in which ink is directly stored in an ink tank and an ink occluding body made of a porous material is arranged between a pen tip and the ink tank. still,
In the present invention, “front” indicates the pen tip side, and “rear” indicates the ink tank side.

[0002]

2. Description of the Related Art Conventionally, in a writing instrument of this kind, for example,
Japanese Utility Model Publication No. 56-33739 discloses that a writing body is fixed to the tip of a barrel, and an ink occluding body having a capillary action, which comes into contact with the rear part of the barrel, communicates with the outside air between the inside of the barrel. The ink storage body is mounted in the shaft cylinder so that a ventilation path can be provided, and a compression member is attached to the rear end of the ink storage body to form a tight gap in the ink storage body at the mounting portion. A writing instrument "in which a portion and an ink tank provided in the rear portion of the barrel are connected by a communication hole."
(See Fig. 6)

[0003] In Japanese Utility Model Laid-Open No. 2-48377,
"In a writing implement with an ink outlet between the ink tank and the tip writing body, the capillary force of the ink adjusting porous body that is placed on the outer periphery of the ink outlet is brought into contact with the ink outlet. , And a porous body for ink adjustment of a writing instrument, in which the outer portion is weakened. (See Fig. 7)

[0004]

However, in the above-mentioned writing instrument (see FIG. 6), the capillary gap at the rear end of the ink occlusion body B is dense due to compression, but most of the other parts are straight, and the capillary is small. The gap width (ie, capillary force) of the gap is substantially uniform. Therefore, when the pen tip is stored in a downward state, most of the retained ink A in the ink storage B tends to concentrate below the ink storage B (that is, in front of the ink storage B). As a result, at the time of impact such as dropping or removing the cap, the ink may leak to the outside.

Further, in the above-mentioned conventional writing instrument, since the ink A tends to concentrate on the front portion of the ink storage body B, when the pressure in the ink tank C is reduced due to a temperature change or the like, the ink A on the front side of the ink storage body B is discharged. It is not easy to return to the ink tank C, and it is easy for air to enter the ink tank C while the ink A remains at the front of the ink storage body B. As a result, when the expansion and contraction of the air in the ink tank C is repeated, the residual ink A in the front part of the ink occluding body B gradually increases, and finally there is a possibility that the ink may leak from the pen tip side. .

In addition, in the above-mentioned conventional writing implement, most of the stored ink A is distributed to the front of the ink occluding body B, and air tends to enter the rear of the ink occluding body B. A ventilation path D that communicates with the outside air is required between the shaft cylinder inner surface. If the air passage D is not present, if the air behind the ink occluding body B expands due to a temperature rise or the like, the ink may be pushed out. Therefore, in the conventional writing implement, the air passage D is provided so as to prevent air from being trapped in the rear portion of the ink occluding body B so as to avoid ink leakage. However, in order to form the air passage D between the inner surface of the barrel and the outer surface of the ink occluding body B, not only is the production time and the production cost increased, but also the member such as the barrel is made of a synthetic resin molded body. In the case of forming, if grooves or ribs for the ventilation path are formed on the inner surface, sinks may occur on the outer surface, which may cause poor appearance and poor airtightness when the cap is attached.

[0007] Further, the conventional writing implement (see FIG. 7).
Changes the capillary force of the ink adjusting porous body B (corresponding to the ink absorbing body B of the present application) in the radial direction, and is strong near the ink outlet E (corresponding to the ink guiding member of the present invention). Even if the outer portion is set weaker, the capillary force is uniform in the axial direction. Therefore, when stored in a state where the pen tip is facing downward, the porous body B for ink adjustment
When the ink A is concentrated on the front part, the ink may leak to the outside at the time of impact such as dropping or at the time of removing the cap.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to provide a direct liquid writing instrument which avoids an ink leakage accident and has a simple structure and a reduced production cost.

[0009]

[Means for Solving the Problems]

(First Invention) The present invention is directed to a direct liquid writing instrument 1 in which an ink occluding body 4 made of a porous material is disposed between a pen tip 2 and an ink tank 3. It is required that an ink retaining section 5 is provided in which the capillary force gradually increases from the front to the rear (claim 1).
(See FIGS. 1, 2, 3, 4, and 5)

The direct liquid writing implement 1 (Claim 1) is provided with an internal pressure of the ink tank 3 in a pen point downward state by an ink holding section 5 in which a capillary force is gradually strengthened from a front part to a rear part of the ink storage body 4. Even if the ink rises, the ink from the ink tank 3 is prevented from being concentrated on the front part of the ink occluding body 4, and as a result, the ink splatters or leaks to the outside at the time of an impact such as dropping or removing the cap. Can be avoided.

The capillary force T and the pen tip water head pressure G In the direct liquid writing instrument 1 of the first aspect, the capillary force T at an arbitrary position in the ink holding section 5 in a state where the pen tip is directed downward is defined as: The head pressure G at the height H from the pen tip 2 to the arbitrary position is made larger than the head pressure G, and the difference between the capillary force T and the head pressure G is calculated from the front end of the ink reservoir 5 to the rear of the ink reservoir 5. It is preferable that the width is gradually increased toward the end (claim 2). (See Fig. 2)

Accordingly, the direct liquid writing implement 1 (claim 2) transfers the overflowing ink in the ink tank 3 when the internal pressure rises from the rear of the ink storage body 4 (ie, the ink storing section 5) to the front. The ink can be distributed over the ink occluding body 4 in the conventional manner, and the air does not enter the rear of the ink occluding body 4 as in the related art.

Therefore, when the pressure inside the ink tank 3 is reduced due to a temperature change or the like, the ink in the ink occluding body 4 (ie, the ink storing section 5) is arranged in order from the front when the direct liquid type writing instrument 1 (Claim 2) is used. It returns smoothly to the ink tank 3 without interruption. As a result, air does not enter the ink tank 3 with the ink remaining at the front part of the ink storage body 4. That is, even if the expansion and contraction of air in the ink tank 3 is repeated, the ink does not remain at the front portion of the ink occluding body 4.
It can be further prevented.

Furthermore, the direct liquid writing instrument (Claim 2)
Since air is not trapped in the rear part of the ink occluding body 4, ink leakage can be avoided without intentionally providing a ventilation path as in the related art. For this reason, the writing implement itself has a simple structure, so that the manufacturing cost can be reduced and the writing implement can be provided at low cost. In addition, when the member such as the shaft cylinder 7 is formed of a synthetic resin molded body, there is no risk of causing poor appearance due to sink marks and poor airtightness when the cap is attached.

In the pen tip downward state, the pen tip water head pressure G changes with the height H from the pen tip 2 to an arbitrary position of the ink holding part 5, that is, G = (ink density ρ) × ( It is represented by gravitational acceleration g) × (height H) and acts in the direction of the pen tip (downward). Further, the ink occlusion body 4
Is set by the size of the voids of the porous material (that is, the density of the porous material), and acts in the ink tank direction (upward).

Contrary to the present invention, when the capillary force T is smaller than the pen tip head pressure G (that is, when T <G), when the pen tip is in the downward state, the ink is absorbed as in the prior art. There is a possibility that the ink may be retained more preferentially in the front part of the ink storage body 4 than in the rear part of the body 4. Further, the capillary force T
The difference (TG) between the head pressure G and the pen tip water head pressure G is gradually reduced from the front of the ink storage body 4 toward the rear of the ink storage body 4. There is a possibility that the ink may be retained more preferentially in the front part of the ink storage body 4 than in the rear part of the body 4.

Liquid-tight part In the direct liquid writing instrument 1 according to claim 1 or 2,
It is preferable that a liquid-tight portion 6 having an appropriate length in the axial direction, which has a stronger capillary force than the ink holding portion 5, is provided at the rear end of the ink holding portion 5 (claim 3). (See FIGS. 1 and 2)

In the direct liquid writing implement 1 (claim 3), the liquid-tight portion 6 is always liquid-sealed with a holding ink. Due to the liquid seal, when the ink is returned from the ink storage unit 5 to the ink tank 3 when the ink tank 3 is depressurized, air is removed from the ink tank 3 before all the ink in the ink storage body 4 is returned to the ink tank 3. 3 is prevented. Therefore, the ink tank 3
When the pressure is reduced, the ink in the ink storage unit 5 can be returned to the ink tank 3 in preference to the air. That is, since the air is not replaced while the ink remains in the ink storage unit 5, the ink is stored in the ink storage unit 5. Does not remain, and there is no possibility that the ink leaks from the front portion of the ink occluding body 4.

Since the liquid-tight portion 6 has an appropriate length in the axial direction, the liquid sealing performance is ensured. The position of the liquid-tight part 6 is preferably the rear end of the ink-absorbing body 4, so that the ink-retaining capacity of the ink-retaining part 5 formed in front of the liquid-tight part 6 is maximized from the ink-absorbing body 4. Can be obtained without waste.

Compression In addition, in the direct liquid writing implement 1 according to any one of claims 1 to 3,
Compressing the outer or inner surface of the ink occluding body 4 in the radial direction,
It is preferable that the capillary force is set to a predetermined strength by changing the gap width of the capillary gap (claim 4). (See FIGS. 1, 2 and 3)

In the case of the fourth aspect, the ink storage body 4
Before compression, it is preferable to have a capillary gap distribution having a uniform gap width in advance, so that after compression, a desired capillary gap distribution (ie, a distribution of capillary forces) can be reliably obtained. it can.

As a method of compressing the ink occluding body 4, for example, a method of compressing the ink occluding body 4 by press-fitting the ink occluding body 4 into the shaft cylinder 7 when attaching the ink occluding body 4, or a method of compressing the ink occluding body 4 A method in which a unit in which 4 is compressed in advance is attached to the shaft cylinder 7 is appropriate.

Further, the constitution of claim 1 (the ink absorbing member 4)
3. An arrangement in which the ink holding section 5 is provided with a strength that is gradually increased from the front to the rear of the ink holding section 5 or an arbitrary position in the ink holding section 5 with the pen point downward. Is higher than the pen head pressure G at a height H from the pen tip 2 to the arbitrary position, and the difference between the capillary force T and the pen head pressure G is calculated by the ink holding unit 5. In order to gradually increase the size from the front end toward the rear end of the ink storing portion 5, the outer or inner surface in the radial direction of the ink occluding body 4 is compressed in a tapered shape, and the gap width of the capillary gap in the axial direction (ie, the capillary tube) It is preferable to change the strength of the force.

By the tapered compression, the width of the capillary gap of the ink occluding member 4 is continuously reduced from the front to the rear of the ink occluding member 4, that is, the capillary force of the ink occluding member 4 is reduced. The strength is continuously increased from the front part to the rear part of the ink occluding body 4, so that the capillary force can be easily and reliably set as described in claim 1 or 2, which is advantageous in manufacturing. Note that the tapered shape includes a substantially continuous change in which the diameter is increased (or reduced) in a fine stepwise manner.

The place where the ink occluding body 4 is compressed into a tapered shape may be either the outer surface or the inner surface of the ink occluding body 4. A configuration in which the outer diameter of the ink occlusion body 4 is gradually reduced from the front to the rear (FIG. 1), while a type in which the inner surface of the ink occlusion body 4 is compressed is, for example, a center hole 41 of the ink occlusion body 4. (FIG. 3) in which the inner diameter of the front end increases from the front to the rear. In addition, the location where the ink occlusion body 4 is compressed in a tapered shape may be on both inner and outer surfaces of the ink occlusion body 4.

The liquid-tight portion 6 (liquid seal portion) is preferably formed by compressing the outer surface or the inner surface of the rear portion of the ink occluding body 4 into a straight shape. Accordingly, the liquid-tight portion 6 having an appropriate length in the axial direction can be easily and reliably formed, which is advantageous in manufacturing as in the case of the above-described tapered compression (see FIGS. 1 and 2). In addition, besides this,
The liquid-tight portion 6 may be constituted by a slit 73 provided in a partition 71 between the ink tank 3 and the ink occluding body 4.

Ink guide member In the direct liquid writing implement 1 according to any one of claims 1 to 4,
An ink guide member 9 having a capillary force stronger than the capillary force of the ink absorber 4 (that is, a capillary force stronger than the liquid-tight portion 6) is provided in the ink absorber 4, and the ink tank 3 and the pen are provided. It is preferable that the communication with the point 2 is established (claim 5).

In this way, the direct liquid writing implement (Claim 5) allows the ink in the ink tank 3 to be constantly supplied to the pen tip 2 via the ink guide member 9 so that the handwriting can be supplied without interruption. Is obtained.

The ink guide member 9 makes the inner surface of the ink storage member 4 (the ink storing portion 5 and the liquid-tight portion 6) come into direct contact with the outer surface of the ink storage member 4 to directly exchange ink with the ink storage member 4. The configuration for performing the above is preferable. Therefore, when writing,
The ink remaining in the ink occluding body 4 can be directly supplied to the pen tip 2 without returning to the ink tank 3, and the ink in the ink occluding body 4 can be quickly and reliably consumed from the pen tip 2. This is effective for preventing ink from remaining in the ink occluding body 4.

By making the capillary force of the ink guide member 9 stronger than the capillary force of the ink occluding member 4 (the ink retaining portion 5 and the liquid-tight portion 6), the ink in the ink tank 3 is made to shine by the ink occluding member 4. The ink is supplied to the ink guiding member 9 preferentially, and the ink is always supplied to the pen tip 2.

It is preferable that the rear end of the ink guide member 9 is exposed or protrudes into the ink tank 3 from the rear end of the ink storage body 4. Thereby, the ink tank 3
To the pen tip 2 from the printer.

The material of the ink guiding member 9 is appropriately selected from the group consisting of a resin of a fiber bundle or a heat-sealed body, and an extruded or injection-molded body of a synthetic resin having an ink outlet in the axial direction.

(Second Invention) The present invention relates to a pen tip 2
A direct liquid writing implement 1 in which an ink occluding body 4 made of a porous material is arranged between the ink occluding body 3 and the ink tank 3. The outer surface of the ink occluding body 4 is gradually reduced in diameter from the front to the rear. It is necessary to provide an ink retaining section 5 which is compressed so as to make the gap width of the capillary gap of the ink occluding body 4 gradually smaller from the front to the rear (claim 6). (See FIGS. 1 and 2)

Accordingly, in the direct liquid type writing instrument 1 (claim 6), since the capillary force of the ink holding section 5 is set to be stronger as it goes backward, the internal pressure of the ink tank 3 rises with the pen point downward. However, the ink from the ink tank 3 is not concentrated on the front portion of the ink occluding body 4, and as a result, the ink can be prevented from splashing or leaking to the outside at the time of an impact such as a drop or when the cap is removed. In addition, since the strength of the capillary force is changed by compressing the outer surface of the ink occluding body 4, the manufacturing becomes easy and the inexpensive direct liquid writing instrument 1 can be provided. Further, the direct liquid writing implement 1
(Claim 6) is preferably provided with the liquid-tight portion 6 according to claim 3.

(Third Invention) The present invention also relates to a pen tip 2
A direct liquid writing instrument 1 in which an ink occluding body 4 made of a porous material is disposed between the ink occluding body 3 and the ink tank 3. The diameter of the ink occluding body 4 gradually decreases from the front to the rear. The tapered compression section 5 is provided, and a straight compression section 6 having a smaller diameter than the tapered compression section 5 is provided at the rear end of the tapered compression section 5 (claim 7). (See FIGS. 1 and 2)

The density of the ink occluding material 4 made of a porous material can be continuously increased from the front portion to the rear portion by the tapered compression portion 5, and the capillary force is increased from the front to the rear portion of the ink occluding material 4. It can be strengthened continuously toward. Thereby, the tapered compression part 5
In order to prevent the ink from being concentrated at the front end of the ink occluding body 4 (tapered compression section 5),
It is possible to prevent the ink from scattering or leaking to the outside at the time of impact such as dropping or removing the cap. In addition, the tapered compression enables easy and reliable setting of the capillary force, which is advantageous in manufacturing.

The straight compression section 6 is always liquid-sealed with ink. Due to the liquid seal, when ink is returned from the tapered compression section 5 to the ink tank 3 when the ink tank 3 is depressurized, air is released before all the ink in the tapered compression section 5 is returned to the ink tank 3. It is prevented from being taken into the ink tank 3. Therefore, when the pressure in the ink tank 3 is reduced, the ink in the tapered compression section 5 can be returned to the ink tank 3 in preference to air, that is, the air is not replaced while the ink remains in the tapered compression section 5. Since the ink does not remain in the tapered compression part 5, there is no possibility that the ink leaks from the front part of the ink storage body 4.

(Fourth Invention) Further, the present invention relates to a pen tip 2
A direct liquid writing implement 1 in which an ink occluding body 4 made of a porous material is arranged between the ink occluding body 3 and the ink tank 3, wherein the inner surface of the ink occluding body 4 gradually increases in diameter from the front to the rear. The ink reservoir 5 is provided so as to be compressed so that the width of the capillary of the ink occluding body 4 is gradually reduced from the front to the rear.
Is required. (See Fig. 3)

Thus, in the direct liquid type writing instrument 1 (claim 8), the capillary pressure of the ink holding section 5 is set to be stronger as it goes backward, so that the internal pressure of the ink tank 3 rises with the pen point downward. However, the ink from the ink tank 3 is not concentrated on the front portion of the ink occluding body 4, and as a result, the ink can be prevented from splashing or leaking to the outside at the time of an impact such as a drop or when the cap is removed. In addition, since the strength of the capillary force is changed by compressing the inner surface of the ink occluding body 4, the manufacturing becomes easy and the inexpensive direct liquid writing instrument 1 can be provided. Further, the direct liquid writing implement 1
(Claim 8) is preferably provided with the liquid-tight portion 6 of claim 3.

(Fifth Invention) The present invention also provides a pen tip 2
A direct liquid writing implement 1 in which an ink occluding body 4 made of a porous material is disposed between the ink occluding body 3 and the ink tank 3. The diameter of the ink occluding body 4 gradually increases from the front to the rear. And a straight compression portion 6 having a larger diameter than the tapered compression portion is provided at the rear end of the tapered compression portion 5 (claim 9).

Accordingly, in the direct liquid writing instrument 1 (claim 9), the density of the ink occluding body 4 made of a porous material is continuously increased by the tapered compression section 5 from the front to the rear. And the capillary force can be continuously increased from the front to the rear of the ink storage body 4. As a result, the ink enters the tapered compression section 5 from the rear end thereof, and the ink is not concentrated on the front of the ink occluding body 4 (tapered compression section 5). Can be prevented from scattering or leaking out of the ink. In addition, the tapered compression enables easy and reliable setting of the capillary force, which is advantageous in manufacturing.

The straight compression section 6 is always liquid-sealed with ink. Due to the liquid seal, when ink is returned from the tapered compression section 5 to the ink tank 3 when the ink tank 3 is depressurized, air is released before all the ink in the tapered compression section 5 is returned to the ink tank 3. It is prevented from being taken into the ink tank 3. Therefore, when the pressure in the ink tank 3 is reduced, the ink in the tapered compression section 5 can be returned to the ink tank 3 in preference to air, that is, the air is not replaced while the ink remains in the tapered compression section 5. Since the ink does not remain in the tapered compression part 5, there is no possibility that the ink leaks from the front part of the ink storage body 4.

Ink occluding body The ink occluding body 4 of the present invention (claims 1 to 9)
Is a porous material, specifically, a heat-fused body of a fiber bundle, a resin processed body of a fiber bundle, a resin processed body of felt, a heat-fused body of felt, a needle punched body of felt, Examples thereof include open cells made of synthetic resin.

Pen tip The pen tip 2 of the present invention (claims 1 to 9) may be any as long as the ink supplied from the ink guide member 9 can be discharged. , Fiber bundle resin or heat fusion processed body, felt processed body, synthetic resin open cell, synthetic resin extruded body, ballpoint pen tip, fountain pen type plate pen, small tubular pen, and the like. Also,
The pen tip 2 and the ink guide member 9 may be configured as a single member, and the ink guide member 9 may be configured to also serve as the pen tip 2.

Ink tank Ink tank 3 of the present invention (claims 1 to 8)
May be formed directly in the barrel 7 (see FIGS. 1 to 5), a separate ink cartridge may be connected to the rear end of the ink storage body 4 (see FIG. 7), or the rear end of the ink tank 3. A configuration in which ink can be replenished from the opening or the like is appropriate.

[0046]

Embodiments of the present invention will be described with reference to the drawings.

(First Embodiment) FIGS. 1 and 2 show a first embodiment of a direct liquid writing instrument 1 according to the present invention. FIG. 1 shows a state in which ink is not stored, and FIG. 2 shows a state in which a pen tip is downward with ink retained.

The direct liquid type writing instrument 1 mainly comprises a shaft cylinder 7 having an occlusion body accommodating portion 8 at a front portion and an ink tank 3 at a rear portion, and an ink occlusion member 4 accommodated in the occlusion body accommodating portion 8. And an ink guide member 9 which also penetrates into the ink occluding body 4 in the axial direction and also serves as the pen tip 2.

The shaft cylinder 7 is an injection-molded body made of a cylindrical synthetic resin (eg, polyethylene, polypropylene, etc.), and has an occluder having a tapered inner surface having a diameter decreasing toward the rear at the front. A body housing portion 8 is provided, and an ink tank 3 which is a space portion for directly storing ink is provided behind the occlusion body housing portion 8 via a partition wall 71. At the rear end opening of the ink tank 3 of the barrel 7,
A tail plug 74 is fixed.

The ink occlusion body 4 made of a heat-sealed body of a synthetic resin fiber bundle (for example, a polyester resin fiber bundle) is press-fitted into the occlusion body accommodating section 8 from the front end opening. Before the ink occlusion body 4 is press-fitted into the occlusion body accommodating section 8, the ink occlusion body 4 has a right cylindrical shape and has a uniform capillary gap (that is, a uniform capillary force). And the above-mentioned occlusion body accommodation part 8
Is a tapered (conical) inner surface whose diameter becomes gradually smaller toward the rear, so that the ink occluding body 4 is compressed along the tapered inner surface, and the density of the fiber increases from the front end to the rear end. Is continuously increased, and an ink retaining section 5 (tapered compression section) is formed in which the capillary force gradually increases from the front to the rear. Further, a straight inner surface having a diameter smaller than that of the tapered inner surface is formed at the rear end of the tapered inner surface of the occluding body housing section 8, whereby the rear end portion of the ink occluding body 4 is compressed into a straight shape. Thus, a liquid-tight part 6 (straight compression part) is formed.

At the axis of the ink occluding member 4, a rod-shaped ink guiding member 9 made of a resin processed material of synthetic resin fiber (for example, polyester fiber or acrylic fiber) is provided from the front to the rear of the ink occluding member 4. The ink guide member 9 is attached by piercing and penetrating so that the outer peripheral surface of the ink guide member 9 is the inner peripheral surface of the ink occluding body 4 (that is, the ink retaining section 5 and the liquid tight section 6).
Is in direct contact with A hard pointed member 91 is fixed to the rear end of the ink guide member 9, thereby improving the insertability into the ink occluding body 4. The front end of the ink guide member 9 is formed in an appropriate shape, and protrudes outward as a pen tip 2.

The partition 71 is provided with a cylindrical support 72 for holding a pointed member 91 at the rear end of the ink guide member 9, and protrudes into the ink tank 3. The cylindrical support portion 72 is provided with a slit 73 for communicating the ink tank 3 with the ink guide member 9 and for communicating the ink tank 3 with the ink occluding body 4 (liquid-tight portion 6).

A pen tip holding member 75 is fixed to the front end opening of the barrel 7, and holds the outer surface of the pen tip 2. The pen tip holding member 75 is provided with a rib 75a on its inner surface, abuts and supports the front end of the ink occluding body 4, and prevents the ink occluding body 4 from dropping off.

FIG. 2 explains the operation of the direct liquid writing instrument 1 of FIG. When the height from the pen tip 2 to an arbitrary position of the ink storage unit 5 is H, the capillary force at the arbitrary position in the ink storage unit 5 is T, and the pen head pressure at the height H is G, The capillary force T is 3 greater than the pen tip head pressure G (that is, T> G). Further, the difference (TG) between the capillary force T and the pen tip head pressure G increases from the front end of the ink storage unit 5 to the rear end of the ink storage unit 5.

Therefore, when the ink tank 3 is filled with ink and stored with the pen tip 2 facing downward, the ink in the ink tank 3 overflows to the ink occluding body 4 according to the change in the internal pressure of the ink tank 3. . The spilled ink is continuously held in the liquid-tight portion 6 at the rear end of the ink occluding body 4 and in the ink storing portion 5 in front of the liquid-tight portion 6 without allowing air to enter. As a result, when the ink tank 3 is depressurized, the return back of the ink from the ink storage unit 5 to the ink tank 3 is made smooth without interruption.

(Second Embodiment) FIG. 3 shows a second embodiment of the direct liquid writing instrument 1 of the present invention.

The direct liquid writing instrument 1 mainly comprises a shaft cylinder 7 having an occluder housing section 8 at the front and an ink tank 3 at the rear, and an ink occluder 4 housed in the occluder housing section 8. And an ink guide member 9 which also penetrates the ink occluding body 4 in the axial direction and also serves as the pen tip 2.

The shaft cylinder 7 is an injection-molded body made of a cylindrical synthetic resin (for example, polypropylene, polyethylene, etc.), and has a tapered insertion portion 81 having a tapered front portion having a smaller diameter toward the front. Is provided with an annular occlusion body accommodating section 8 provided in the above. An ink tank 3, which is a space for directly storing ink, is provided behind the storage unit 8 via a partition 71. The ink tank 3 of the barrel 7
A tail plug 74 is fixed to the rear end opening.

The partition 71 is provided with the ink tank 3.
A slit 73 is provided for communicating the ink storage unit 4 with the ink storage unit 4, and the insertion portion 81 protruding forward on the storage unit storage unit 8 side is integrally connected. The insertion portion 81
It comprises a straight outer surface of the base and a tapered outer surface tapering forward from the straight outer surface.

The ink occlusion body 4 made of a heat-sealed body of a synthetic resin fiber bundle (for example, a polyester fiber bundle) is press-fitted into the occlusion body accommodating portion 8 from the front end opening. Since the occlusion body accommodating portion 8 is provided with the insertion portion 81 at the axis thereof, when the ink occlusion body 4 is press-fitted, the insertion portion 81 is inserted into the axis of the ink occlusion body 4. The inner surface of the axial center of the ink occluding body 4 is compressed along the tapered outer surface and the straight outer surface of the insertion portion 81. The ink retaining portion 5 (tapered compression portion) in which the gap width of the capillary gap is continuously reduced toward the rear portion and the capillary force is gradually increased from the front portion to the rear portion by the tapered outer surface.
At the same time, the liquid-tight portion 6 (straight compression portion) is formed by the straight outer surface.

An ink guide member 9 made of a resin processed body made of synthetic resin fiber (for example, polyester fiber, acrylic fiber, etc.) is inserted through the axis of the insertion portion 81. The rear end of the ink guide member 9 projects into the ink tank 3, while the front end of the ink guide member 9 projects outside the front end of the barrel 7 as the pen tip 2.

As in the first embodiment, a pen tip holding member 75 is fixed to the front end opening of the barrel 7, and holds the outer surface of the pen tip 2. The pen tip holding member 75 is provided with a rib 75a on the inner surface, and the rib 75a supports the front end of the ink occluding member 4 so as to prevent the ink occluding member 4 from falling off.

(Third Embodiment) FIG. 4 shows a third embodiment of the direct liquid writing instrument 1 according to the present invention. This is because the ink occluder 4
Before assembling into the shaft cylinder 7, the capillary gap is gradually made denser from the front end to the rear end. Since compression is not used, the shape is a straight cylindrical shape.
The operation and effect of this embodiment and other configurations are the same as those of the first embodiment.

(Fourth Embodiment) FIG. 5 shows a fourth embodiment of the direct liquid writing instrument 1 of the present invention. The ink occluding body 4 is composed of a plurality of annular bodies 4a, 4b, 4c, 4d, 4e, and 4f having different capillaries densities, which are made of synthetic resin open cells;
Those having a large capillary gap (ie, having a weak capillary force) 4f and those having a small capillary gap (ie, having a strong capillary force) 4a are stacked in order from the front end to the rear end so that the capillary force gradually increases toward the rear. It is a configuration that is set. The operation and effect of this embodiment and other configurations are the same as those of the first embodiment.

[0065]

According to the first aspect of the present invention, even if the internal pressure of the ink tank rises with the pen pointed downward, the direct liquid writing instrument concentrates the ink from the ink tank on the front part of the ink occluding body. As a result, it is possible to prevent the ink from scattering or leaking to the outside at the time of impact such as dropping or removing the cap.

According to the present invention, the direct liquid type writing instrument can distribute the overflowing ink in the ink tank when the internal pressure is increased from the rear part of the ink occluding body to the front part thereof. As described above, the ink is concentrated at the front of the ink occluding body so that air does not enter the rear of the ink occluding body. Therefore, even if the expansion and contraction of air is repeated in the ink tank, the ink does not remain in the ink storage body, so that it is possible to further prevent the ink from leaking at the time of impact such as dropping or at the time of removing the cap.

Furthermore, the direct liquid writing instrument (Claim 2)
Because air is not trapped in the rear of the ink storage body,
Ink leakage can be avoided without intentionally providing a ventilation path as in the related art. For this reason, the writing implement itself has a simple structure, so that the manufacturing cost can be reduced and the writing implement can be provided at low cost. In addition, when a member such as a shaft cylinder is formed of a synthetic resin molded body, there is no risk of causing poor appearance due to sink marks and poor airtightness when the cap is attached.

According to the third aspect of the present invention, when the ink tank is depressurized, the ink of the ink occluding body can be returned to the ink tank without interruption, and the ink does not remain in the ink occluding body. There is no risk of ink leaking from the front of the ink occluding body.

According to the fourth aspect of the present invention, the direct liquid writing instrument can easily and reliably set the strength of the capillary force, which is advantageous in manufacturing.

According to the fifth aspect of the present invention, the ink in the ink tank is always supplied to the pen tip through the ink guide member, and the ink can be discharged without interruption in the handwriting. I do.

According to the sixth aspect of the present invention, even when the internal pressure of the ink tank rises with the pen pointed downward, the direct liquid writing instrument concentrates the ink from the ink tank on the front part of the ink storage body. As a result, it is possible to prevent the ink from scattering or leaking to the outside at the time of impact such as dropping or removing the cap. In addition, since the strength of the capillary force is changed by compressing the outer surface of the ink occluding body, the manufacturing becomes easy and an inexpensive direct liquid writing instrument can be provided.

According to the present invention, since the ink is not concentrated on the front portion of the ink absorbing member by the tapered compression portion, the direct liquid writing instrument of the present invention has the advantage that the ink can be removed at the time of impact such as dropping or removing the cap. Splashes and leakage to the outside can be avoided. In addition, the strength of the capillary force can be easily and reliably set by the tapered compression, which is advantageous in manufacturing. In addition, the straight compression section allows the ink in the ink occluding body to return to the ink tank without any interruption, so that the ink does not remain in the ink occluding body and there is no possibility that the ink leaks from the front portion of the ink occluding body.

According to the present invention, even if the internal pressure of the ink tank rises with the pen pointed downward, the ink from the ink tank concentrates on the front part of the ink storage body. As a result, it is possible to prevent the ink from scattering or leaking to the outside at the time of impact such as dropping or removing the cap. In addition, since the strength of the capillary force is changed by compressing the inner surface of the ink occlusion body, the manufacturing becomes easy and an inexpensive direct liquid writing instrument can be provided.

According to the present invention, since the ink is not concentrated on the front part of the ink absorbing member by the tapered compression part, the direct liquid type writing instrument according to the ninth aspect of the present invention has the advantage that the ink can be used at the time of impact such as dropping or at the time of removing the cap. Splashes and leakage to the outside can be avoided. In addition, the strength of the capillary force can be easily and reliably set by the tapered compression, which is advantageous in manufacturing. In addition, the straight compression section allows the ink in the ink occluding body to return to the ink tank without any interruption, so that the ink does not remain in the ink occluding body and there is no possibility that the ink leaks from the front portion of the ink occluding body.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a first embodiment of the present invention.

FIG. 2 is a longitudinal sectional view for explaining the operation of the first embodiment of the present invention.

FIG. 3 is a longitudinal sectional view showing a second embodiment of the present invention.

FIG. 4 is a longitudinal sectional view showing a third embodiment of the present invention.

FIG. 5 is a longitudinal sectional view showing a fourth embodiment of the present invention.

FIG. 6 is a longitudinal sectional view showing a conventional example.

FIG. 7 is a longitudinal sectional view showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Direct liquid writing implement 2 Pen tip 3 Ink tank 4 Ink occlusion body 4a-4f Annular body 5 Ink storing part (tapered compression part) 6 Liquid tight part (straight compression part) 7 Shaft cylinder 71 Partition wall 72 Cylindrical support part 73 Slit 74 Tail plug 75 Pen tip holding member 75 a Rib 8 Occlusion body storage section 81 Insertion section 9 Ink guide member 91 Pointed member 10 Ink H Height from pen tip to any position of ink holding section T The above in ink holding section Capillary force at arbitrary position G Nib head pressure at height H

Claims (9)

[Claims] 1. A direct liquid type writing instrument having an ink occluding body made of a porous material disposed between a pen tip and an ink tank, wherein the ink occluding body is provided with a capillary tube gradually from a front portion to a rear portion thereof. A direct liquid type writing implement characterized by having an ink holding section with increased strength. 2. The method according to claim 1, wherein the capillary force at an arbitrary position in the ink holding portion is made larger than the head pressure of the pen tip at a height from the pen tip to the arbitrary position in the downward state of the pen tip. 2. The direct liquid writing implement according to claim 1, wherein the difference in the head pressure of the pen tip is gradually increased from the front end of the ink holding section toward the rear end of the ink holding section. 3. A direct liquid writing instrument according to claim 1, wherein a liquid-tight part having a stronger capillary force than the ink holding part and having an appropriate length in the axial direction is provided at a rear end of the ink holding part. . 4. The capillary force is set to a predetermined strength by radially compressing an outer surface or an inner surface of the ink occluding body and changing a gap width of the capillary gap. Direct writing instrument. 5. The ink storage device according to claim 1, further comprising an ink guide member having a capillary force greater than that of the ink storage member, and communicating between the ink tank and the pen tip. The direct liquid writing implement according to 1, 2, 3, or 4. 6. A direct liquid type writing instrument in which an ink occluding body made of a porous material is disposed between a pen tip and an ink tank, wherein the outer surface of the ink occluding body extends from the front to the rear. A direct-liquid writing implement, comprising: an ink retaining portion that is compressed so as to have a gradually smaller diameter and a gap width of a capillary gap of the ink occluding body is gradually reduced from a front portion to a rear portion thereof. 7. A direct liquid writing instrument having an ink occluding body made of a porous material disposed between a pen tip and an ink tank, wherein the ink occluding body is provided on an outer surface of the ink occluding body from a front portion to a rear portion thereof. A direct liquid writing instrument, comprising: a tapered compression portion having a gradually decreasing diameter; and a straight compression portion having a smaller diameter than the tapered compression portion is provided at a rear end of the tapered compression portion. 8. A direct liquid type writing instrument in which an ink occluding body made of a porous material is disposed between a pen tip and an ink tank, wherein an inner surface of the ink occluding body is arranged from a front portion to a rear portion thereof. A direct-liquid writing implement, comprising: an ink retaining portion that is compressed so as to have a gradually larger diameter, and the gap width of the capillary gap of the ink occluding body is gradually reduced from the front to the rear. 9. A direct liquid type writing instrument having an ink occluding body made of a porous material disposed between a pen tip and an ink tank, wherein the ink occluding body is provided on an inner surface of the ink occluding body from a front portion to a rear portion thereof. A direct liquid writing instrument, comprising: a tapered compression portion having a gradually increasing diameter; and a straight compression portion having a larger diameter than the tapered compression portion is provided at a rear end of the tapered compression portion.