JP2022104014A - Pressure-type writing tool - Google Patents

Abstract

To obtain a pressure-type writing tool capable of temporarily pressurizing and ejecting ink without being affected by a change in the amount of ink inside the ink storage tube, and allowing a user to adjust the amount of ink outflow.SOLUTION: The pressure-type writing tool includes a barrel, a writing body that is housed inside the barrel and is arranged so that it can move relative to the barrel in the axial direction, a bullet that urges the writing body forward, and a piston member that is inserted into the writing body from behind and is arranged so that it cannot move relative to the barrel. The writing body is provided with at least a pen tip and an ink storage tube. The ink storage tube contains ink, and an ink backflow preventive body is loaded behind the ink. At the front end of the piston member, a pressurizing portion is formed inside the ink backflow preventive body. As the writing body retracts due to the writing pressure during writing, the pressurizing portion pressurizes the ink backflow preventive body from behind.SELECTED DRAWING: Figure 3

Description

The present invention relates to a pressurized writing instrument. More specifically, the present invention relates to a pressurized writing instrument that is pressurized by the writing pressure at the time of writing.

Conventionally, it is widely known that a liquid is discharged from a tip hole provided in the front of the main body, such as a writing tool such as a ballpoint pen or a marker, a pen-shaped correction fluid, or a coating tool such as liquid glue. A structure that can increase the amount of runoff is also known.

For example, in a writing instrument, as in Patent Document 1 (Japanese Unexamined Patent Publication No. 2000-335173), a pressurizing mechanism is provided behind the ink accommodating tube to pressurize the inside of the ink tank in conjunction with the pressing operation of the knock body. , Patent Document 2 (Japanese Unexamined Patent Publication No. 2017-119406) uses a structure that pressurizes the inside of the ink tank by using the writing pressure at the time of writing to increase the amount of ink flowing out from the pen tip. It is considered to make the brush stroke thicker or darker.

Further, in the coating tool, as in Patent Document (Japanese Unexamined Patent Publication No. 9-290598), by pressing the side surface of the flexible container to pressurize the inside, the correction fluid flows to the tip of the chip and the paper surface or the like. It has a structure to be applied to, and is used in correction fluid to correct typographical errors.

Japanese Unexamined Patent Publication No. 2000-335173 Japanese Unexamined Patent Publication No. 2017-119406 Japanese Unexamined Patent Publication No. 9-290598

However, in the writing tools of Patent Document 1 and Patent Document 2, since the pressurization by the pressurizing mechanism has a structure of pressurizing the air layer behind the ink contained in the ink tank, the ink is written by writing. When the amount of ink in the tank decreases, the volume of air to be compressed increases and it becomes difficult to apply pressure.As a result, the amount of outflow changes due to the difference in the amount of ink remaining. there were.

Further, in the writing instruments of Patent Document 1 and Patent Document 2, in the pressurized state, the ink always under pressure at the time of writing is forcibly ejected, and the user can reduce the amount of ink outflow. It wasn't thought of being able to adjust.

Further, in the case of the coating tool of Patent Document 3, for example, in the case of a pen-type correction fluid, the amount of the correction fluid flowing out tends to change depending on the force applied by the user who pushes the side surface of the container during pressurization, and the amount of the correction fluid flows out many times. Sometimes my fingers got tired when I had to push the container. Further, in the case of liquid glue in which the liquid glue is housed in a flexible container, the liquid glue may be discharged too much by pushing the container too strongly, and the moisture may cause the paper to be twisted.

An object of the present invention is that the ink can be temporarily pressurized and ejected without being affected by a change in the amount of ink inside the ink containing tube, and the user can adjust the amount of ink outflow. To get a pressure-type writing tool.

The present invention includes a shaft cylinder, a writing body housed inside the shaft cylinder and arranged so as to be relatively movable in the axial direction with respect to the shaft cylinder, and an elastic body that urges the writing body forward. The writing body is provided with a piston member inserted into the writing body from behind and arranged so as not to be movable relative to the barrel, and the writing body is provided with at least a pen tip and an ink accommodating tube. Ink is built in the ink accommodating tube, an ink backflow preventive body is filled behind the ink, and a pressure is applied to the front end of the piston member, which is disposed in the ink backflow preventive body. A pressure-type writing tool in which a portion is formed, and the writing body retracts due to the writing pressure at the time of writing so that the pressure portion pressurizes the ink backflow prevention body from the rear. be.

According to the present invention, a pressurizing portion is formed at the front end of the piston member, which is arranged in the ink backflow prevention body, and the pressurizing portion is retracted by the writing pressure at the time of writing. By pressurizing the ink backflow preventive body from the rear, it is possible to directly pressurize the ink backflow preventive body adjacent to the ink only at the time of writing. As a result, the ink can be temporarily pressurized and ejected without being affected by the change in the amount of ink inside the ink storage tube, and the user can adjust the amount of ink outflow.

Preferably, the pressurizing portion is always arranged in the ink backflow preventive body until the ink is completely consumed by writing. According to this, the ink is temporarily pressurized and ejected without being affected by the change in the amount of ink inside the ink storage tube from the start of use of the writing tool to the writing state where the ink is completely consumed. Can be done.

Preferably, the ink containing tube includes a small diameter portion and a large diameter portion. In this case, the ink accommodating tube can be filled with a necessary and sufficient amount of the ink backflow preventive body, and even if the ink is consumed and the ink backflow preventive body advances with the use of the pressure type writing tool of the present invention, the ink backflow preventive body is added. The pressure part does not separate from the ink backflow prevention body. As a result, the ink can be temporarily pressurized and ejected without being affected by the change in the amount of ink inside the ink storage tube from the start of use of the writing tool to the writing state where the ink is completely consumed. It will be more possible.

Preferably, the ink is housed only in the small diameter portion, the ink backflow preventive body is housed across the small diameter portion and the large diameter portion, and the pressurizing portion is the ink backflow preventive body in the large diameter portion. It is arranged only in. As a result, the pressurizing portion can reliably pressurize the ink backflow preventive body at the time of writing. Also, when writing is stopped and the writing pressure is no longer applied, the cursive moves forward with respect to the barrel. In other words, the piston member (pressurized portion) moves relative to the ink backflow prevention body in the direction of exiting. In this case as well, since there is sufficient space between the pressure portion and the large diameter portion to allow the ink backflow prevention body to flow, it is possible to prevent the ink from being pulled strongly backward and air from flowing in from the pen tip. be able to.

According to the present invention, a pressurizing portion is formed at the front end of the piston member, which is arranged in the ink backflow prevention body, and the pressurizing portion is retracted by the writing pressure at the time of writing. By pressurizing the ink backflow preventive body from the rear, it is possible to directly pressurize the ink backflow preventive body adjacent to the ink only at the time of writing. As a result, the ink can be temporarily pressurized and ejected without being affected by the change in the amount of ink inside the ink storage tube, and the user can adjust the amount of ink outflow.

It is a schematic vertical sectional view of the pressure type writing tool in embodiment of this invention, and is the figure which shows the state which the cap is attached. It is a schematic vertical sectional view of the pressure type writing instrument in the state which the cap of FIG. 1 is removed, and is the figure which shows the non-writing state (the state which the writing pressure is not applied to the pen tip). It is an enlarged vertical sectional view of a main part of the pressure type writing tool of FIG. FIG. 3 is an enlarged vertical sectional view of a main part showing a state in which a weak writing pressure is applied in the pressure-type writing instrument according to the embodiment of the present invention. FIG. 3 is an enlarged vertical sectional view of a main part showing a state in which a strong writing pressure is applied in the pressure-type writing tool according to the embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the pressurized writing instrument 10 of the present embodiment, "front" refers to the pen tip 13a side, and "rear" refers to the opposite side.

FIG. 1 is a schematic vertical sectional view of a pressurized writing instrument 10 according to an embodiment of the present invention, and is a diagram showing a state in which a cap 11 is attached. FIG. 2 is a schematic vertical cross-sectional view of the pressure-type writing instrument 10 in a state where the cap 11 of FIG. 1 is removed, and is a diagram showing a non-writing state (a state in which writing pressure is not applied to the pen tip 13a). Further, FIG. 3 is an enlarged vertical sectional view of a main part of the pressurized writing tool 10 of FIG.

The state of the pressure-type writing instrument 10 of FIGS. 1 to 3 is a state in which writing pressure is not applied to the pen tip 13a, and the front contact portion 13cc of the writing body 13 (holder 13ca) is a shaft cylinder 12 (front shaft). 12aa) is in contact with the front stopper 12ab.

On the other hand, FIG. 4 is an enlarged vertical cross-sectional view of a main part showing a state in which a weak writing pressure is applied in the pressure-type writing instrument 10 according to the embodiment of the present invention. Further, FIG. 5 is an enlarged vertical sectional view of a main part showing a state in which a strong writing pressure is applied in the pressure-type writing tool 10 according to the embodiment of the present invention.

The state of the pressure-type writing instrument 10 of FIGS. 4 and 5 is a state in which writing pressure is applied to the pen tip 13a, and the front contact portion 13cc of the writing body 13 (holder 13ca) is a shaft cylinder 12 (front shaft). 12aa) is in a state of being separated from the front stopper 12ab. Further, in FIG. 5, since a strong writing pressure is applied, the rear contact portion 13bc of the writing body 13 (ink storage tube 13b) abuts on the rear stopper 12bb of the barrel 12 (rear shaft 12ba). It is in a state of being.

<Shaft tube>
The pressurized writing instrument 10 of the present embodiment shown in FIGS. 1 to 5 includes a cylindrical shaft cylinder 12 having an opening at the front end. In the present embodiment, the axle cylinder 12 has a front shaft 12aa and a rear shaft 12ba, and as shown in FIG. 1, a cap 11 is attached to the front of the front shaft 12aa. Although the pressurized writing tool 10 of the present embodiment is a cap type writing tool, the present invention can also be applied to a knock type writing tool that does not require a cap to be attached.

As shown in FIGS. 1 to 5, since the front shaft 12aa and the rear shaft 12ba are detachably fixed by screw connection (screw), the cursive 13 described later can be replaced at any time. However, the front shaft 12aa and the rear shaft 12ba may be fixed by a fitting bond or may be integrally formed.

The barrel 12 includes a front stopper 12ab that regulates the forward movement of the cursive 13 and a rear stopper 12bb that regulates the backward movement of the cursive 13. As shown in FIGS. 3 to 5, in the present embodiment, the front axle 12aa is provided with the front stopper 12ab, and the rear axle 12ba is provided with the rear stopper 12bb.

When no writing pressure is applied to the pen tip 13a, the front stopper 12ab comes into contact with the front contact portion 13cc of the cursive body 13 (holder 13ca). As a result, the amount of protrusion of the pen tip 13a from the front end opening of the front shaft 12aa becomes constant in a state where the writing pressure is not applied to the pen tip 13a, and the feeling of use at the beginning of writing by the user is always unified.

Further, when a strong writing pressure is applied to the pen tip 13a, the rear stopper 12bb comes into contact with the rear contact portion 13bc of the writing body 13 (ink storage tube 13b). As a result, even when an excessively high writing pressure is applied to the pen tip 13a, the ink 14 (ink backflow preventive body) can be excessively pressed to prevent the ink 14 from being excessively ejected from the pen tip 13a. can. In the state where the writing pressure is not applied to the pen tip 13a, as a matter of course, the ink 14 is not pressurized (the state where the pressure is not applied to the rear end of the ink composition), so that the pen tip 13a is from the tip. No ink leakage occurs.

Further, a tail crown 18 may be provided at the rear end of the barrel 12, and in the present embodiment, the tail crown 18 is a friction body made of an elastic material. For example, as shown in FIG. 1, a mounting hole may be formed in the rear end portion of the rear shaft 12ba in the rear direction, and a friction body made of an elastic material may be press-fitted into the mounting hole. As a result, the friction body can be fixed to the outer surface of the rear end portion of the rear shaft 12ba. Further, the rear shaft 12ba to which the friction body (tail crown 18) is fixed to the rear end is connected to the rear end portion of the front shaft 12aa, so that the friction body is always fixed to the rear end of the axle cylinder 12. Will be. The tail crown 18 may be made of resin (for example, polypropylene, polyethylene, polycarbonate, ABS, etc.).

As the elastic material constituting the friction body, for example, a synthetic resin (rubber, elastomer) having elasticity is preferable, and for example, a silicone resin, an SBS resin (styrene-butadiene-styrene copolymer), and a SEBS resin (styrene-ethylene-butylene) are preferable. -Styrene copolymer), fluororesin, chloroprene resin, nitrile resin, polyester resin, ethylenepropylene diene rubber (EPDM) or a mixture of two or more rubber elastic materials, and a mixture of rubber elastic material and synthetic resin. And so on.

The elastic synthetic resin constituting the friction body is preferably not a highly wear-resistant elastic material (for example, an eraser) but a low-wear elastic material in which almost no wear residue (eraser) is generated during friction. .. Further, the friction body may be provided on the outer surface of the rear end portion of the barrel 12 in various ways. For example, an embodiment in which a friction body made of an elastic material is press-fitted, engaged, screwed, fitted, bonded, bonded, or formed on the outer surface of the rear end of the barrel 12 or the outer surface of the rear end of the rear shaft 12ba by two-color molding or the like. Alternatively, the entire shaft cylinder 12 or the entire rear shaft 12ba may be integrally formed of an elastic material.

<Cursive>
Inside the barrel 12, a cursive 13 arranged so as to be relatively movable in the axial direction with respect to the barrel 12 is housed. In the present embodiment, the writing body 13 includes a pen tip 13a, a synthetic resin holder 13ca holding the rear outer surface of the pen tip 13a, and an ink storage tube 13b fixed to the rear end of the holder 13ca. The cursive 13 may not have a holder, and the pen tip 13a and the ink storage tube 13b may be directly fitted to each other.

The cursive 13 may include a tail plug (not shown) attached to the rear end opening of the ink storage tube 13b. The breechblock is provided with an air hole that opens toward the rear end. The air holes allow ventilation between the inside and the outside of the ink storage tube 13b. When the tail plug is provided at the rear end opening of the ink storage tube 13b, the elastic body 17, which will be described later, comes into contact with the rear portion of the tail plug and urges the cursive body 13 forward. Further, when the tail plug has axial elasticity, even if an excessively high writing pressure (a writing pressure higher than the writing pressure at which the rear stopper 12bb contacts the rear contact portion 13bc) is applied to the pen tip 13a, the tail is used. The stopper absorbs excessive writing pressure and can protect the pen tip 13a without damaging it.

The cursive 13 includes a front contact portion 13 bc that regulates the forward movement of the cursive 13 and a rear contact portion 13 bc that regulates the backward movement of the cursive 13. As shown in FIGS. 3 to 5, in the present embodiment, the holder 13ca is provided with the front contact portion 13cc, and the ink storage tube 13b is provided with the rear contact portion 13bc.

When no writing pressure is applied to the pen tip 13a, the front contact portion 13cc comes into contact with the front stopper 12ab of the barrel 12 (front shaft 12aa). As a result, as described above, when the writing pressure is not applied to the pen tip 13a, the amount of protrusion of the pen tip 13a from the front end opening of the front shaft 12aa becomes constant, and the user feels at the beginning of writing is always unified. To.

Further, when a strong writing pressure is applied to the pen tip 13a, the rear contact portion 13bc comes into contact with the rear stopper 12bb of the barrel 12 (rear shaft 12ba). As a result, as described above, even when an excessively high writing pressure is applied to the pen tip 13a, the ink 14 (ink backflow preventive body) is excessively pressurized and the ink 14 is excessively ejected from the pen tip 13a. Can be prevented. In the state where the writing pressure is not applied to the pen tip 13a, as a matter of course, the ink 14 is not pressurized (the state where the pressure is not applied to the rear end of the ink composition), so that the pen tip 13a is from the tip. No leakage of ink 14 occurs.

<Pen tip>
The pen tip 13a protrudes from the opening at the front end of the shaft cylinder 12 (front shaft 12aa), and writing is possible. The pen tip 13a is, for example, a metal ballpoint pen tip that rotatably holds a ball at the front end. Inside the pen tip 13a, a spring that presses the ball at the front end forward is housed. The spring has, for example, a configuration in which a rod portion is provided at the front end portion of the compression coil spring, and the front end of the rod portion is in contact with the rear surface of the ball.

When not writing, the forward urging of the spring causes the ball to be in close contact with the inner surface of the inwardly facing front edge of the front end of the ballpoint pen tip. This prevents the ink 14 from leaking from the front end of the pen tip 13a and the ink 14 from evaporating. Further, the pressurized writing instrument 10 of the present invention is more preferable because the spring is provided inside the pen tip 13a to prevent undesired leakage of ink 14 due to pressurization.

<Ink storage tube>
The ink 14 described later is built in the ink storage tube 13b, and the ink backflow prevention body 15 is filled behind the ink 14. Further, in the present embodiment, the ink accommodating tube 13b includes a small diameter portion 13ba in the front and a large diameter portion 13bb in the rear. In this case, the ink accommodating tube 13b can be filled with the necessary and sufficient amount of the ink backflow preventive body 15, and the ink 14 is consumed with the use of the pressure type writing tool 10 of the present invention, and the ink backflow preventive body 15 advances. Even so, the pressurizing portion 16a, which will be described later, does not separate from the ink backflow prevention body 15. As a result, the ink 14 is temporarily pressurized and ejected without being affected by the change in the amount of ink inside the ink accommodating tube 13b from the start of use of the writing tool to the writing state in which the ink 14 is completely consumed. Is more possible.

Further, as shown in FIGS. 3 to 5, in the present embodiment, a chamfered portion is provided at a corner portion formed on the inner surface of the connecting portion between the small diameter portion 13ba and the large diameter portion 13bb. The chamfered portion refers to a portion where a C surface, an R surface, or the like is formed, and can be applied to both a concave corner portion and a convex corner portion. The chamfered portion in the present embodiment is a convex curved surface R chamfer and a concave curved surface R chamfer.

According to this, when writing is stopped and the writing pressure is no longer applied, the piston member 16 (pressurizing portion 16a) moves relative to the ink backflow prevention body 15 in the direction of exiting, and instead the ink backflow prevention body 15 Moves forward relative to each other. At that time, since the ink backflow prevention body 15 can smoothly flow from the large diameter portion 13bb toward the small diameter portion 13ba, the ink 14 is pulled backward and air flows in from the pen tip 13a. Can be prevented.

The ink 14 is housed only in the small diameter portion 13ba, the ink backflow prevention body 15 is housed across the small diameter part 13ba and the large diameter part 13bb, and the pressurizing part 16a is housed in the ink backflow prevention body 15 in the large diameter part 13bb. It is arranged only in. As a result, the pressurizing portion 16a can reliably pressurize the ink backflow prevention body 15 at the time of writing. Further, when writing is stopped and the writing pressure is no longer applied, the cursive body 13 moves forward with respect to the barrel 12. In other words, the piston member 16 (pressurized portion 16a) moves relative to the ink backflow prevention body 15 in the direction of exiting. Also in this case, since there is a sufficient space between the pressurizing portion 16a and the large diameter portion 13bb for the ink backflow prevention body 15 to flow, the ink 14 is strongly pulled backward and air flows in from the pen tip 13a. It is possible to prevent it from happening.

<Ink>
In the present embodiment, the ink 14 housed in the ink storage tube 13b is a heat-discolorable ink. The heat-changing ink is preferably a reversible heat-changing ink. The reversible heat-discoloring ink is a heat-decoloring type that decolorizes by heating from the color-developing state, a color memory-preserving type that alternately stores and retains the color-developing state or the decoloring state in a specific temperature range, or heats from the decoloring state. It is possible to configure various types individually or in combination, such as a heating color-developing type that develops a color and returns to a decolorized state by cooling from the color-developed state.

Examples of the coloring material contained in the reversible thermochromic ink include (a) an electron-donating color-developing organic compound, (b) an electron-accepting compound, and (c) a reaction in which both of them are chemically bonded (c). A reversible thermochromic pigment in which a reversible thermochromic composition containing at least three essential components of a reaction medium that determines the occurrence temperature of a color reaction) is encapsulated in a microcapsule is preferably used.

The ink 14 used in the present invention is not limited to the heat-changing ink, and other ink compositions other than the heat-changing ink can also be used. For example, a writing ink, a correction fluid, a liquid glue, a cosmetic liquid, or the like may be appropriately selected depending on the intended use as a liquid ejector. The writing ink is not particularly limited to oil-based ink and water-based ink, and ink having shear thinning property can also be used.

Further, a heat-changing ink using a reversible heat-changing pigment containing a heat-changing material as a colorant contains a coloring material in a capsule, so that it is generally difficult to increase the writing density. By using the pressurized writing instrument 10 having the structure of the present invention, it is possible to increase the writing density by increasing the amount of ink outflow due to pressurization.

As a method for increasing the brush stroke concentration of the heat-changing ink containing the reversible heat-changing pigment, the amount of the reversible heat-changing pigment as a colorant may be increased, or the particle size of the reversible heat-changing pigment may be increased. Although it may be increased, when the amount of the reversible thermochromic pigment is increased, the viscosity of the ink becomes high and it becomes difficult for the ink to flow out, and when the particle size of the reversible thermochromic pigment is increased, the pigment becomes the ink. It becomes difficult to pass through the flow path, and there is a possibility that it becomes difficult for ink to flow out. However, even with such an ink, the pressure-type writing tool 10 having the structure of the present invention can forcibly eject the ink by pressurizing the ink. Therefore, the configuration of the present embodiment is adopted for the heat-discolorable writing tool. It is also recommended to do.

Further, even an ink having a relatively high specific gravity solid content such as titanium oxide or a bright pigment in the liquid and having a high viscosity when allowed to stand so that the solid content does not settle in the liquid can be added to the structure of the present invention. The pressure type writing tool 10 can forcibly eject the ink by pressurizing the ink, similarly to the heat-changing ink containing a reversible heat-changing pigment. Further, even when a dry liquid adheres to the tip, such as a correction fluid or liquid glue, the liquid can be pressurized to facilitate discharge. As described above, the pressurized writing tool 10 of the present invention has a structure suitable as a ejection tool for various liquids (ink 14).

The ink composition for writing tools used in the present invention is not particularly limited, such as oil-based ink, water-based ink, and shear-reducing viscosity ink, but when the writing tip is separated from the paper surface even in the writing state (writing). Since it is not pressurized (in the state where no pressure is applied), it can be suitably used for inks with relatively low viscosity, and it is possible to increase the amount of ink outflow and improve the writing density by pressurization, so that it is reversible. It is preferably used for a heat-changing ink containing a heat-changing pigment and a writing tool for writing on a non-penetrating surface.

<Ink backflow prevention body>
Examples of the ink backflow prevention body 15 include a liquid plug. The faucet consists of, for example, a non-volatile liquid and / or a refractory liquid (base oil). Specifically, vaseline, spindle oil, castor oil, olive oil, refined mineral oil, liquid paraffin, polybutene, α-olefin, α-olefin oligomer or co-oligoene, dimethyl silicone oil, methylphenyl silicone oil, amino-modified silicone oil, poly. Examples thereof include ether-modified silicone oil and fatty acid-modified silicone oil, which may be used alone or in combination of two or more.

Non-volatile liquids and / or non-volatile liquids may be thickened to a suitable viscosity by adding a gelling agent. Examples of the gelling agent include silica having a hydrophobic surface treated, fine particle silica having a methylated surface, aluminum silicate, swelling mica, a clay-based thickener such as bentonite or montmorillonite having a hydrophobic treatment, and magnesium stearate. , Fatty acid metal soaps such as calcium stearate, aluminum stearate, zinc stearate, trivendilidene sorbitol, fatty acid amide, amide-modified polyethylene wax, hydrophobic mash oil, dextrin-based compounds such as fatty acid dextrin, and cellulose-based compounds. Polybutene or silicone oil is preferably used as the base oil of the ink backflow preventive body 15, and fatty acid amide or silica is preferably used as the thickener.

<Repellent>
Further, inside the barrel 12, an elastic body 17 for urging the cursive body 13 forward is provided. The rear portion of the elastic body 17 is in contact with or locked to a spring stopper provided at the rear portion of the rear shaft 12ba. In this embodiment, the spring stopper corresponds to a partition wall provided behind the rear shaft 12ba. The front portion of the elastic body 17 is in contact with the rear end (rear end of the ink storage tube 13b) of the cursive body 13 and urges the cursive body 13 forward.

The tension of the elastic body 17, that is, the load that the writing body 13 moves backward when the writing pressure is applied to the pen tip 13a is preferably 20 gf (low writing pressure state) to 400 gf (high writing pressure state). More preferably, it is 50 gf (low writing pressure state) to 300 gf (high writing pressure state). That is, in a low writing pressure state, the front contact portion 13cc of the cursive 13 begins to separate from the front stopper 12ab of the barrel 12, and the cursive 13 begins to move backward. On the other hand, in a high writing pressure state, the writing body 13 moves backward until the rear contact portion 13bc of the writing body 13 comes into contact with the rear stopper 12bb of the barrel 12.

<Piston member>
Further, inside the barrel 12, a piston member 16 inserted into the cursive 13 from behind and arranged so as not to move relative to the barrel 12 is provided. At the front end of the piston member 16, a pressurizing portion 16a arranged in the ink backflow prevention body 15 is formed, and the writing body 13 retracts due to the writing pressure at the time of writing, so that the pressurizing portion 16a becomes ink. The backflow prevention body 15 is pressurized from the rear.

Further, as shown in FIGS. 3 to 5, in the present embodiment, a chamfered portion is provided at a corner portion formed around the pressure portion 16a, which is the front end of the piston member 16. The chamfered portion refers to a portion where a C surface, an R surface, or the like is formed, and can be applied to both a concave corner portion and a convex corner portion. In this embodiment, the convex C chamfer is applied.

According to this, when writing is stopped and the writing pressure is no longer applied, the piston member 16 (pressurizing portion 16a) moves relative to the ink backflow prevention body 15 in the direction of exiting, and instead the ink backflow prevention body 15 Moves forward relative to each other. At that time, since the ink backflow prevention body 15 can smoothly flow from the rear of the piston member 16 toward the pressurizing portion 16a, the ink 14 is pulled backward and air flows in from the pen tip 13a. You can prevent that.

The piston member 16 is preferably made of resin (for example, polypropylene, polyethylene, polyacetal, etc.) or stainless steel. When the piston member 16 is made of polypropylene, polyethylene, or polyacetal, the ink backflow prevention body 15 does not easily adhere to the outer surface of the piston member 16, so that the ink backflow prevention body 15 does not hinder the advance of the ink backflow prevention body 15 due to ink consumption. Suitable.

The pressurizing portion 16a is always arranged in the ink backflow prevention body 15 until the ink 14 is completely consumed by writing. According to this, the ink 14 is temporarily pressurized without being affected by the change in the amount of ink inside the ink accommodating tube 13b from the start of using the writing tool to the writing state in which the ink 14 is completely consumed. It can be discharged.

The haunting type writing tool 10 having the above configuration operates as follows.

In the present invention, the shaft cylinder 12, the writing body 13 housed inside the shaft cylinder 12 and arranged so as to be relatively movable in the axial direction with respect to the shaft cylinder 12, and the writing body 13 are attached to the front. The writing body 13 includes a repulsive projectile 17 and a piston member 16 inserted into the writing body 13 from behind and arranged so as not to be relatively movable with respect to the barrel 12. It is provided with at least a pen tip 13a and an ink accommodating tube 13b, an ink 14 is built in the ink accommodating tube 13b, an ink backflow prevention body 15 is filled behind the ink 14, and a front end of the piston member 16. Is formed with a pressurizing portion 16a disposed in the ink backflow prevention body 15, and the writing body 13 retracts due to the writing pressure at the time of writing, so that the pressurizing portion 16a causes the ink backflow. By pressurizing the preventive body 15 from the rear, the ink backflow preventive body 15 adjacent to the ink 14 can be directly pressurized only at the time of writing. As a result, the ink 14 can be temporarily pressurized and ejected without being affected by the change in the amount of ink inside the ink storage tube 13b, and the user can adjust the outflow amount of the ink 14.

In other words, by directly pressurizing the ink backflow prevention body 15 adjacent to the ink 14 only during writing, the amount of ink 14 flowing out from the pen tip 13a can be temporarily increased, and the handwriting can be arbitrarily thickened. Alternatively, it can be thickened. Further, in the pressure type writing tool 10 according to the structure of the present invention, unlike the pressure mechanism in the conventional pressure type writing tool, the ink backflow prevention body 15 does not pressurize the ink 14 or the air layer behind the ink backflow prevention body 15. In addition, since the structure is such that pressure is directly applied to the ink 14 to facilitate ejection, the user can adjust the outflow amount of the ink 14 without being affected by the change in the amount of ink inside the main body.

Further, the pressurizing unit 16a is always arranged in the ink backflow prevention body 15 until the ink 14 is completely consumed by writing, so that the ink 14 is completely consumed from the start of use of the writing instrument. The ink 14 can be temporarily pressurized and ejected without being affected by the change in the amount of ink inside the ink accommodating tube 13b until the state is reached.

Further, by providing the ink accommodating tube 13b with a small diameter portion 13ba and a large diameter portion 13bb, the ink accommodating tube 13b can be filled with a necessary and sufficient amount of the ink backflow preventive body 15, and the pressurizing type of the present invention can be provided. Even if the ink 14 is consumed and the ink backflow prevention body 15 advances with the use of the writing tool 10, the pressurizing portion 16a does not separate from the ink backflow prevention body 15. As a result, the ink 14 is temporarily pressurized and ejected without being affected by the change in the amount of ink inside the ink accommodating tube 13b from the start of use of the writing tool to the writing state in which the ink 14 is completely consumed. Is more possible.

Further, the ink 14 is housed only in the small diameter portion 13ba, the ink backflow prevention body 15 is housed straddling the small diameter portion 13ba and the large diameter portion 13bb, and the pressurizing portion 16a is housed in the large diameter portion 13bb. It is arranged only in the ink backflow prevention body 15 inside. As a result, the pressurizing portion 16a can reliably pressurize the ink backflow prevention body 15 at the time of writing.

Further, when writing is stopped and the writing pressure is no longer applied, the cursive body 13 moves forward with respect to the barrel 12. In other words, the piston member 16 (pressurized portion 16a) moves relative to the ink backflow prevention body 15 in the direction of exiting. Also in this case, the ink 14 is housed only in the small diameter portion 13ba, the ink backflow prevention body 15 is housed across the small diameter portion 13ba and the large diameter portion 13bb, and the pressurizing portion 16a is housed in the large diameter portion 13ba. By disposing only in the ink backflow prevention body 15 in the portion 13bb, it is possible to largely guide the ink 14 backward and prevent air from flowing in from the pen tip 13a. Further, the air inflow from the pen tip 13a, which may occur when writing is stopped and the writing pressure is no longer applied, contains the above-mentioned spring that presses the ball at the front end forward inside the pen tip 13a. By being there, it can be prevented more. Therefore, it is preferable to provide the above-mentioned spring in the present invention.

10 Pressurized writing instrument 11 Cap 12 Shaft cylinder 12aa Front shaft 12ab Front stopper 12ba Rear shaft 12bb Rear stopper 13 Cursive 13a Pen tip 13b Ink storage tube 13ba Small diameter part 13bb Large diameter part 13bb Rear contact part 13ca Holder 13cc Front contact part 14 Ink 15 Ink backflow prevention body 16 Piston member 16a Pressurizing part 17 Repellent body 18 Tail crown

Claims (4)

A cursive, a cursive housed inside the cursive and arranged so as to be relatively movable in the axial direction with respect to the cursive, a cursive that urges the cursive forward, and the cursive. A piston member inserted into the body from the rear and arranged so as not to move relative to the barrel is provided.
The cursive is provided with at least a pen tip and an ink accommodating tube, the ink accommodating tube contains ink, and the back of the ink is filled with an ink backflow preventive body.
A pressure portion disposed in the ink backflow prevention body is formed at the front end of the piston member, and the pressure portion retracts due to the writing pressure at the time of writing, so that the pressure portion becomes the ink. A pressure-type writing instrument characterized in that the backflow prevention body is pressurized from behind. The pressure-type writing tool according to claim 1, wherein the pressure-pressing unit is always arranged in the ink backflow preventive body until the ink is completely consumed by writing. The pressurized writing tool according to claim 1 or 2, wherein the ink storage tube includes a small diameter portion and a large diameter portion. The ink is housed only in the small diameter portion, the ink backflow preventive body is housed across the small diameter portion and the large diameter portion, and the pressure portion is housed in the ink backflow preventive body in the large diameter portion. The pressurized writing instrument according to claim 3, wherein only the pressure type writing tool is arranged.

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