JP5094473B2 - Pressurized writing instrument - Google Patents

Description

  The present invention relates to a pressure-type writing instrument in which a pumping-type pressure mechanism is provided at a rear end portion of an ink containing tube and a pressure mechanism portion is operated by pressing of a knock body.

  Conventionally, a pressure-type writing instrument in which a pumping-type pressure mechanism is provided at the rear end of the ink containing tube and the pressure mechanism is operated by pressing the knocking body is disclosed in Japanese Patent Application Laid-Open No. 2000-335173. As disclosed in “Ball Pen”, a structure in which the inside of the ink filling tube is pumped into a pressurized state in association with the pushing operation of the knock mechanism so as to be kept sealed is well known.

  In such a pressure-type writing instrument, when the pressurized state is released, it is necessary to return the sealed space to the original amount corresponding to the compressed space, and the pressurized space is released. At this time, if the pressure in the pressurizing space reaches near atmospheric pressure due to ink consumption or the like, a negative pressure state lower than the atmospheric pressure is reached, and the ink for the writing instrument filled in the ink containing tube is ink. There was a possibility that the ink would move to the rear end side of the storage cylinder and ink backflow would occur.

By the way, in Japanese Patent Application Laid-Open No. 2007-62114 “ballpoint pen”, by using a porous body having a communication hole in the pressure member and / or the seal member, the pressurized air is released over time when the pressure member is in a pressurized state for a long time. Thus, a structure for releasing the pressurizing space is disclosed.
JP 2000-335173 A JP 2007-62114 A

  However, in Patent Document 1, in order to prevent the ink for writing instruments from moving to the rear end side of the ink storage cylinder, it is necessary to take measures against negative pressure by increasing the ink viscosity and reducing the fluidity of the ink. It was necessary to sacrifice the writing taste.

  In Patent Document 2, although the pressure is gradually reduced over time, a negative pressure may be generated when releasing the pressurized space during normal use. It does not prevent backflow due to movement toward the end side.

  An object of the present invention is to prevent a negative pressure state lower than the atmospheric pressure from being generated at the rear end portion of the ink storage cylinder when releasing the pressure state in a pressure-type writing instrument that pressurizes by a pressing operation of a knock body. It is to provide a pressure-type writing instrument.

According to the present invention, the shaft cylinder has a writing tip portion at the tip of the ink storage cylinder, and stores a writing body that is directly filled with the ink for the writing instrument, and is added to the rear end portion of the ink storage cylinder. By providing a pressure mechanism and pressing the knock body disposed by being biased rearward by a coil spring, the pressure mechanism is operated, and a locking portion provided on the knock body is integrated with the shaft cylinder. The urging force of the coil spring is obtained by locking the locked portion formed on the formed or attached member, maintaining the pressurized state, and releasing the locking portion locked on the locked portion. A pressure-type writing instrument capable of releasing the pressure state by the pressure mechanism, wherein the pressure mechanism comprises at least a cylinder capable of communicating with the rear end portion of the ink containing cylinder, a first sealing portion, and a second sealing portion. The knock body can be moved back and forth and interlocked with the cylinder. The first sealing part and the second sealing part seal the inside of the cylinder by the advancement of the knock body, and then the cylinder is advanced in conjunction with the knock body. The air is compressed and pressure is applied to the rear end portion of the ink containing cylinder , and either the first sealing portion or the second sealing portion is pressed against the end surface of the cylinder to form a seal. When the body is retracted , the first sealing part or the second sealing part pressed against the end surface of the cylinder is retracted by the biasing force of the coil spring to release the sealing in the cylinder, and in the cylinder and after the ink storage cylinder. After the end is set to the same pressure as the atmospheric pressure, the cylinder is retracted.

  Further, the writing body is urged and stored in the rear end direction of the shaft cylinder by the second coil spring, and the locking body provided on the knock body is integrated with the shaft cylinder by pressing the knock body. When the locking tip formed on the member formed or attached to the hooked portion is locked to maintain the writing tip of the writing body protruding from the tip of the shaft tube, and the locking portion is unlocked, 2 It is provided with a retracting mechanism capable of immersing the writing tip of the writing body into the shaft tube by the urging force of the coil spring, and the mounting load of the coil spring is smaller than the mounting load of the second coil spring. Features.

  The first sealing portion and the second sealing portion are made of an elastic body.

Furthermore, the other sealing part of the first sealing part or the second sealing part is press-fitted into the cylinder, and the first sealing part or the second sealing part press-fitted into the cylinder in conjunction with the retreat of the cylinder. It is characterized by releasing the press-fitting of the sealed part .

Furthermore, the first sealed part or the second sealed part that is in pressure contact with the end face of the cylinder has a thin-walled deformed part that facilitates deformation.

Furthermore, the viscosity of the ink for writing instruments is an oil-based ink having a viscosity of 10000 mPa · s or less at 20 ° C. and a shear rate of 3.8 sec ⁻¹ .

  In the present invention, the forward movement means moving in the direction of the tip opening of the shaft cylinder, and the movement in the opposite direction is defined as backward movement.

  The present invention relates to a pressure-type writing instrument that pressurizes by a pressing operation of a knock body, and a pressure type that does not generate a negative pressure state lower than atmospheric pressure at the rear end portion of the ink storage cylinder when the pressure state is released. We were able to provide writing instruments.

  Next, examples of the shaft cylinder of the writing instrument of the present invention will be described with reference to the drawings, but the present invention is not limited to the following examples.

Example 1
1 to 8, a pressure-type writing instrument 1 is configured such that a front shaft 2 and a rear shaft 3 are screwed together to constitute a shaft cylinder body, and a writing body 11 disposed in the shaft cylinder body is disposed in the piston 5. The O-ring 16 is detachably press-fitted and the second coil spring 14 presses the piston 5 and the writing body 11 press-fitted into the piston 5 through the spring receiving member 13 toward the rear end of the rear shaft 3. This is a pressure-type writing instrument 1 that is provided with a mechanism for extending and retracting the writing tip portion 12 that is slidably disposed by being biased.

The mechanism of appearing and retracting the writing tip 12 of the writing body 11 is conventionally known. When the knocking body 4 is pressed in the direction of the tip opening 2a of the front shaft 2 (in the direction of arrow F in FIG. 1), the knocking body 4 The locking portion 4b formed on the outer wall of the clip 10 is locked to the locked portion 10a at the tip portion of the clip 10, and the writing tip portion 12 of the writing body protrudes from the tip opening portion 2a of the front shaft 2. By maintaining and pressing the rear end of the clip 10 (in the direction of arrow G in FIG. 2) to release the locking portion 4b locked to the locked portion 10a of the clip, the biasing force of the second coil spring 14 it is retractable mechanism is Ru can be immersed in cursive writing tip 12 the front axle 2 of the distal end opening 2a of.

  The clip 10 has a third coil spring 15 disposed between the outer wall of the rear end portion of the rear shaft 3 and the inner wall of the clip 10, so that the tip portion of the clip 10 faces the outer wall surface of the rear shaft 3. It is always bulleted and attached. Further, by pressing the rear end portion of the clip 10 (in the direction of arrow G in FIG. 2), the connecting portion R between the clip 10 and the rear shaft 3 serves as a fulcrum, and the tip inner wall portion of the clip 10 is the outer wall surface of the rear shaft 3. It can be separated from.

The writing body 11 is provided with a writing tip portion 12 composed of a ballpoint pen tip holding a ball rotatably at the tip of an ink containing cylinder, and ink inside at 20 ° C. and a shear rate of 3.8 sec ⁻¹ (10 rpm). Oil-based ballpoint pen ink (not shown) having a viscosity of 8000 mPa · s is directly filled.

  The rear end portion of the writing body 11 is press-fitted and held in the piston 5, and communicates the inside and outside of the piston 5 through an air hole 5 a formed in the piston 5. Further, a cylinder 6 is disposed so as to cover the piston 5, and a step formed on the outer wall of the piston 5 abuts on a step formed on the inner wall of the cylinder 6. It arrange | positions so that a movement in the front-end | tip opening part 2a direction of the axis | shaft 2 is possible. A coil spring 9 is disposed between the outer wall of the piston 5 and the knock body 4, and the knock body 4 is always urged toward the rear end of the rear shaft 3.

  The pressurizing mechanism provided in the rear shaft 3 includes a piston 5, a first sealing portion 7, and a second sealing portion 8. When the pressure is applied, the knock body 4 first has a front end opening 2 a of the front shaft 2. By moving forward, the first sealing part 7 and the second sealing part 8 seal the inside of the cylinder 6. Thereafter, in conjunction with the knock body 4, the cylinder 6 moves forward toward the front end opening 2 a side of the front shaft 2, thereby compressing the air in the sealed cylinder 6. Since the cylinder 6 and the rear end portion of the writing body 11 can communicate with each other by the air hole 5 a of the piston 5, the mechanism applies pressure to the rear end portion of the writing body 11.

Further, when releasing the pressurization state, the second sealing portion 8 is also retracted by the urging force of the coil spring 9 in conjunction with the backward movement of the knock body 4 toward the rear end of the rear shaft 3 to release the sealing. In this mechanism, the inside of the cylinder 6 and the rear end portion of the writing body 11 are set to the same pressure as the atmospheric pressure, and then the cylinder 6 is retracted in conjunction with the retraction of the knock body 4 to release the press-fitting of the first sealed portion 7. .

  The pressurizing mechanism and the retracting mechanism will be described in detail. When the knock body 4 is advanced in the direction of the distal end opening 2a of the front shaft 2 from the position where the writing distal end 12 of FIG. 3 is immersed, first, as shown in FIG. A thin deformed portion 8 a of the second sealing member 8 made of an elastic body and mounted in the knock body 4 is in pressure contact with the rear end surface 6 b of the cylinder 6. After that, as shown in FIG. 5, the first sealing member 7 made of an elastic body, which is attached to the piston 5, is press-fitted into the inner wall surface 6 c at the tip of the cylinder 6 to seal the inside of the cylinder 6. Further, when the knock body 4 moves forward in the direction of the front end opening 2a of the front shaft 2, the front end surface 4c of the knock body 4 comes into contact with a step formed on the outer wall of the cylinder 6 as shown in FIG. Is advanced in the direction of the front end opening 2 a of the front shaft 2. When the cylinder 6 sealed inside is advanced in the direction of the front end opening 2 a of the front shaft 2, the space in the cylinder 6 is compressed until the inner wall 6 c of the cylinder 6 comes into contact with the outer wall step of the piston 5.

  At this time, since the rear end portion of the writing body 11 is press-fitted into the piston 5 and the piston 5 communicates with the cylinder 6 through the air hole 5a, the space portion in the cylinder 6 is compressed. Since the space in the piston 5 is also compressed, pressure can be applied to the rear end of the writing body 11.

  When the knock body 4 is further advanced in the direction of the front end opening 2 a of the front shaft 2, as shown in FIG. 7, the locking portion 4 b formed on the outer wall of the knock body 4 is locked to the locked portion 10 a at the front end of the clip 10. The writing tip 11 can be maintained in a state where the writing tip 11 protrudes from the tip opening 2 a of the front shaft 2.

When the locking portion 4b locked to the locked portion 10a of the clip 10 is released, the knock body 4 is first retracted toward the rear end of the rear shaft 3 by the urging force of the coil spring 9. At this time, as shown in FIG. 8, the second sealing member 8 that is in pressure contact with the rear end surface 6 b of the cylinder 6 also moves backward with the knock body 4 toward the rear end of the rear shaft 3. The sealing of the rear end portion of the cursive body 11 is released to make it the same pressure as the atmospheric pressure. At this time, since the knock body 4 is loosely fitted in the fitting hole 4a of the knock body 4 so that the fitting protrusion 6a provided on the cylinder 6 can be moved back and forth, only the knock body 4 is located behind the rear shaft 3. Retreat in the end direction.

  Thereafter, the knock body 4 is retracted in the rear end direction of the rear shaft 3 until it abuts on the step portion 3a in the rear shaft 3, but the fitting provided on the cylinder 6 on the front end surface of the fitting hole 4a of the knock body 4 After the mating protrusion 6a abuts, the cylinder 6 also moves backward in the direction of the rear end of the rear shaft 3 in conjunction with the knock body 4, so that the first sealing member 7 press-fitted into the cylinder 6 is released.

Incidentally, when releasing the locking portion 4 b which engages the engaged portion 10a of the clip 10, by the biasing force of the second coil spring 14, cursive 11 press-fitted to the piston 5 and the piston 5, the cylinder 6, the knock body 4 is retracted in the direction of the rear end of the rear shaft, and the writing front end portion 12 of the writing body 11 is immersed from the front end opening 2 a of the front shaft 2. (State of FIG. 3)

  As described above, the pressurizing mechanism of the present invention moves the rear end surface of the cylinder 6 in conjunction with the backward movement of the knock body 4 in the rear end direction by the urging force of the coil spring 9 when releasing the sealed space. The cylinder 6 is moved in the direction of the rear end of the rear shaft 3 until the second sealing member 7 that has been in pressure contact with 6b is retracted, the sealing is released, and the rear end of the writing body 11 is at the same pressure as the atmospheric pressure. Since it does not retreat, it does not become a negative pressure state whose atmospheric pressure is lower than atmospheric pressure.

  If the inside of the cylinder can be sealed, the sealing method is not particularly limited, but either the first sealing part or the second sealing part is pressed against the end surface of the cylinder to form a seal, and the seal is released. Occasionally, by adopting a structure in which the sealing is released from the side in pressure contact with the end face of the cylinder, it can be easily released, for example, less force is required for releasing.

In addition, when either the first sealed part or the second sealed part is press-fitted into the cylinder, when the knock body moves backward toward the rear end of the shaft cylinder, the knock body gradually increases until the press-fit is released. In order to retreat, the impact of releasing the knocking body is mitigated.

  The first sealing portion and the second sealing portion are most preferably formed of an elastic body in consideration of sealing performance. As elastic bodies, elastically deformable butyl rubber, fluorine rubber, butadiene rubber, styrene butadiene rubber, urethane rubber, other synthetic rubbers, thermoplastic elastomers, and other generally known elastic bodies are used. In consideration of the hermeticity depending on the amount, it is preferable to use a non-air permeable or non-air permeable elastic body, and most preferably epichlorohydrin rubber (CO).

  In addition, the shape of the first sealed portion and the second sealed portion is not particularly limited, but the first sealed portion or the second sealed portion that is in pressure contact with the end surface of the cylinder has a thin deformed portion that facilitates deformation. Thus, the sealing performance can be improved.

  The pressure to pressurize is not particularly limited, but considering the insufficient pressurization due to overwriting and the ball falling off at the tip of the tip due to overpressure, etc., 1.05 to 2 times the atmospheric pressure, Preferably, it is 1.1 times or more.

  In the present embodiment, for the sake of convenience, the writing tip of the writing body is not limited to a knock-type writing instrument that protrudes and protrudes from the tip opening of the shaft cylinder, but the writing tip of the writing body protrudes and protrudes from the tip opening of the shaft cylinder. When using the knock type writing instrument, when the knock body is pressed by making the mounting load of the second coil spring that biases the writing body larger than the mounting load of the coil spring that biases the knock body, First, after the coil spring that urges the knock body is compressed to form a pressurized state, the writing tip portion of the writing body can be projected, which is preferable.

  In this embodiment, the piston is press-fitted and attached to the rear end of the cursive body, but the ink container and the piston may be integrally formed. In addition, the loose-fitting structure of the cylinder and the knock body can be moved back and forth by the distance to release the sealing of the second sealing portion when the knock body is retracted, and the cylinder can be retracted in conjunction with the retraction of the knock body. There is no particular limitation.

Further, in this example, oil ballpoint pen ink, which is a Newtonian ink, is used for the sake of convenience, but it is not particularly limited, such as oil-based ink or water-based ink imparted with shear thinning, correction liquid, glue, etc. When the viscosity at 20 ° C. and a shear rate of 3.8 sec ⁻¹ (10 rpm) exceeds 10,000 mPa · s, the writing quality deteriorates, so that it is 10000 mPa · s or less, preferably 8000 mPa · s or more. Moreover, since it will be easy to generate | occur | produce from a chip | tip tip if it is less than 100 mPa * s, it is most preferable to set it as 100 mPa * s or more and 10000 mPa * s or less.

The ink viscosity can be measured using a Brookfield DV-II viscometer (No. 27 rotor) under an environment of 20 ° C. and a shear rate of 3.8 sec ⁻¹ (10 rpm). Although not shown, it is most preferable to incorporate a coil spring that presses the ball into the chip to suppress ink leakage from the tip of the chip.

  Since the pressure-type writing instrument of the present invention is not limited to the type of ink and the nib and the appearance mechanism, it can be widely used as a knock-type writing instrument and a pressure-type writing instrument.

1 is a longitudinal sectional view showing a pressure-type writing instrument of Example 1. FIG. It is a figure which shows the state which the writing front-end | tip part of the writing body in FIG. 1 protruded. It is a principal part expanded sectional view in FIG. It is the principal part enlarged view which a part of which showed the state which the 2nd sealing part pressed against the cylinder. It is the principal part enlarged view which abbreviate | omitted partially which shows the state which sealed the inside of a cylinder. It is the principal part enlarged view which abbreviate | omitted one part which shows the pressurized state. It is the principal part enlarged view which abbreviate | omitted partially which shows the state which the writing front-end | tip part of the cursive body protruded. It is the principal part enlarged view which abbreviate | omitted partially which shows the state which cancelled | released the sealing state.

Explanation of symbols

1 pressurized writing instrument 2 front axle 2a distal opening 3 after the shaft 3a stepped portion 4 knock body 4a fitting hole 4b locking portion 4c leading end surface 5 a piston 5a air holes 6 cylinder 6a engaging projection 6b rear end face 6c inner wall 7 a one sealing part 8 second sealing portion 8a thin deformable section 9 the coil spring 10 clips 10a engaged portion 11 cursive 12 writing tip 13 the spring receiving member 14 and the second coil spring 15 the third coil springs 16 O-ring

Claims (6)

The shaft cylinder has a writing tip at the tip of the ink storage cylinder, and stores a writing body that is directly filled with ink for the writing instrument, and a pressure mechanism is provided at the rear end of the ink storage cylinder. The pressing mechanism is operated by pressing the knocking body arranged to be biased rearward by a coil spring, and the locking portion provided on the knocking body is integrally formed or attached to the shaft cylinder. Locked to the locked portion formed on the member, maintained in a pressurized state, and released from the locked portion locked to the locked portion, thereby being pressurized by the biasing force of the coil spring A pressure-type writing instrument capable of releasing the pressure, wherein the pressure mechanism comprises at least a cylinder capable of communicating with a rear end portion of the ink containing cylinder, a first sealing portion, and a second sealing portion, and the knock body The cylinder can be moved back and forth and interlocked with the cylinder. By the advancement of the knock body, the first sealed portion and the second sealed portion seal the inside of the cylinder, and then the cylinder is advanced in conjunction with the knock body to compress the air in the sealed cylinder. Then, pressure is applied to the rear end portion of the ink containing cylinder , and either the first sealing portion or the second sealing portion is pressed against the end surface of the cylinder to form a seal, and when the knock body is retracted, The first sealing part or the second sealing part pressed against the end face of the cylinder is retracted by the urging force of the coil spring , the sealing inside the cylinder is released, and the rear end part of the cylinder and the ink containing cylinder are enlarged. A pressure-type writing instrument in which the cylinder is retracted after the same pressure as the atmospheric pressure. The writing body is urged and stored in the rear end direction of the shaft cylinder by the second coil spring, and the locking body provided on the knock body is formed integrally with the shaft cylinder by pressing the knock body. Alternatively, the second coil is obtained by locking the hooked portion formed on the attached member to keep the writing tip of the writing body protruding from the tip of the shaft tube and releasing the locking of the locking portion. It is provided with a retracting mechanism capable of immersing the writing tip of the writing body into the shaft tube by the biasing force of the spring, and the mounting load of the coil spring is smaller than the mounting load of the second coil spring. The pressure-type writing instrument according to claim 1. The pressure-type writing instrument according to claim 1 or 2, wherein the first sealing portion and the second sealing portion are made of an elastic body. The other sealed part of the first sealed part or the second sealed part is press-fitted into the cylinder, and the first sealed part or the second sealed part is press-fitted into the cylinder in conjunction with the retreat of the cylinder. The press -type writing instrument according to any one of claims 1 to 3, wherein the press-fitting is released . The pressure-type writing instrument according to any one of claims 1 to 4, wherein the first sealing portion or the second sealing portion that is in pressure contact with the end surface of the cylinder has a thin-walled deformation portion that facilitates deformation. . The pressure-type writing instrument according to any one of claims 1 to 5, wherein the viscosity of the ink for the writing instrument is 10000 mPa · s or less at 20 ° C and a shear rate of 3.8 sec ^-1 .

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