JP2010105371A - Retractable writing utensil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve problems that, when an utensil is left while making a pen nib side face downward, and the rising, setting, and storage of the pen nib are repeatedly carried out, a difficult volatility liquefied material contacts with and penetrates to the pen nib inserted at a front edge of a writing utensil body from a periphery of a writing utensil body so that the difficult volatility liquefied material is mixed with an ink in the pen nib to beat the ink and to make writing thin in the retractable writing utensil in which a difficult volatility liquefied material is arranged at a sliding portion where a writing utensil body rubs and moves while contacting in order to assure the inhibition of abrasion, liquid tightness, and air tightness. <P>SOLUTION: In the retractable writing utensil, a writing utensil body 2 having a pen nib 3 is arranged at a front edge freely movably back and forth in a surrounding sheath object 1, and the writing utensil body 2 slides to and contacts with the other part material when making the writing utensil body 2 move back and forth so that the pen nib 3 may project and retreat from the surrounding sheath object tip opening 1a by an operation. In the retractable writing utensil, the difficulty volatility liquefied material is intervened in the sliding/contacting portion, and an annular movement control portion for the difficult volatility liquefied material is arranged between the sliding/contacting portion and the pen nib 3. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention provides a writing instrument main body having a pen tip at the tip that can be moved back and forth in the exterior body, and when the writing instrument body is moved back and forth so that the pen tip protrudes / immerses from the exterior body tip opening by operation. The present invention relates to a retractable writing instrument that is in sliding contact with other members.

Patent Document 1 discloses a multi-core writing instrument in which a writing instrument main body having a pen tip that is installed so as to be movable back and forth in the exterior body is made to appear and disappear alternately from the front end of the exterior body by an operation. And this multi-core type writing instrument forms the hardly volatile liquid substance layer in the part which mutually contacts when the writing instrument main body moves back and forth.
Further, in Patent Document 2, a hardly volatile liquid material is applied to the inner surface of a cap that is detachable with respect to the shaft cylinder of the writing instrument, and the hardly volatile liquid material applied to the inner surface of the cap causes There has been disclosed a cap-type writing instrument that has a reduced coefficient of friction and can prevent damage and printing of the surface of the shaft tube, peeling of a paint film, and prevention of corrosion when the surface treatment is incomplete.
Japanese Patent Laid-Open No. 9-207494 Japanese Utility Model Publication No. 62-154982

In the invention described in Patent Document 1, the hardly volatile liquid material arranged at the portion where the writing instrument bodies are in sliding contact with each other by being left with the pen tip facing down or repeatedly appearing in and out of the pen tip. In some cases, the sliding contact associated with the gravity or the appearance operation may reach the tip of the pen tip along the outer peripheral surface of the writing instrument body. When the hardly volatile liquid material reaches the nib, there is a problem that the hardly volatile liquid material mixes with the ink in the nib or repels the ink, thereby thinning the handwriting.
Moreover, although the dent is formed in the outer surface of the writing instrument main body in the invention described in Patent Document 2, in the case of a cap type, depending on the operation of removing or fitting the cap, the inner surface of the cap may come into contact with the pen tip. When the gripped hand is attached, the hardly volatile liquid material adheres to the front shaft before the dent, so that the hardly volatile liquid material adheres to the pen tip or the front shaft near the pen tip. The volatile liquid material may reach the nib and come into contact with the pen tip, as in the case of Patent Document 1, the hardly volatile liquid material is mixed with the ink in the nib, There was a problem that ink did not get on the writing surface or the handwriting was thinned.

  That is, the present invention is arranged such that the writing instrument body having a pen tip at the tip is movably moved back and forth in the exterior body, and when the writing instrument body is moved back and forth so as to protrude and immerse the pen tip from the exterior body tip opening by operation, In a retractable writing instrument in which the writing instrument body is in sliding contact with another member, a hardly volatile liquid substance is interposed in the sliding contact part, and the movement with respect to the annular hardly volatile liquid substance is performed between the sliding contact part and the pen tip. The gist of an in / out type writing instrument with a restricting section is provided.

  The writing instrument main body is housed in the exterior body, and the non-volatile liquid substance intervening in the sliding contact part of the writing instrument main body does not come into direct contact with the hand etc., and there is an annular shape between the sliding contact part of the writing instrument main body and the pen tip. By providing a movement restriction part for the hardly volatile liquid material, it becomes an obstacle when the hardly volatile liquid material flows along the outer peripheral surface of the writing instrument main body to the pen tip side, and the hardly volatile liquid material moves to the pen tip. By suppressing contact and intrusion, it is possible to suppress as much as possible that ink does not adhere to the writing surface or thin the handwriting.

  Since the movement restricting part for the annular refractory liquid material is a variable diameter part with a different diameter of the writing instrument body, the path to the pen tip can be increased, and the diameter has changed. As a result, a dent or a convex portion is formed, so that a barrier of a hardly volatile liquid material is formed, and the progress of the hardly volatile liquid material can be suppressed.

  Further, when the movement restricting portion for the hardly volatile liquid material is a pore that holds the hardly volatile liquid material by a capillary force, the hardly volatile liquid material reaching the pore is absorbed by the capillary force of the pore. It can be retained and further progress can be suppressed.

  Furthermore, when the movement restricting portion for the hardly volatile liquid material is a portion where the arithmetic average roughness (Ra) is larger than the sliding contact portion, a portion that is wettable with respect to the hardly volatile liquid material will be formed. The movement from the movement restricting portion having a large arithmetic average roughness (Ra) can be suppressed.

  The writing instrument body is a member that has a pen tip at the tip and contains ink therein. As the nib, a ballpoint pen, a fiber converging body, a porous body such as urethane, or a synthetic resin nib having a communication hole can be used as appropriate. In addition, the ink may be stored in a free state directly in the main body without penetrating into an ink storage body such as a fiber converging body or using an ink storage body. As for the ink used, dyes and / or pigments can be used as colorants, and water and organic solvents can be used as appropriate as the main medium.

  For the operation of moving the writing instrument body, various known methods such as a knock member arranged at the rear end of the retractable writing instrument and a slide mechanism on the side part can be adopted. Further, an elastic member such as a coil spring can be arranged between the members to help drive by operation and to seal the lid member.

  The sliding contact part with respect to the other members of the writing instrument body is between the writing instrument bodies in the case of a multi-core writing instrument, between the tip opening of the exterior body and the writing instrument body in the case of a retractable writing instrument, and between the writing instrument body and the exterior body. And a member disposed between the writing instrument body and the exterior body. In the case of a multi-core writing instrument, the writing instrument body is slidably contacted to reduce the shaft diameter. In the case of a retractable writing instrument, the pen tip of the writing instrument body is reduced by reducing the tip diameter of the exterior body in order to suppress pen tip play. Touch the tip.

A device that seals the accommodation space of the pen tip by the sliding contact portion requires a lid member that opens / liquid-tightly and air-tightly closes the front end opening of the exterior body. The lid member for opening / liquid-tight and air-tightly closing the distal end opening of the exterior body opens / liquid-tight and air-tightly closes the distal end opening of the pen tip accommodating space in conjunction with the longitudinal movement of the writing instrument body. That is, when the writing instrument main body moves forward, the tip opening of the pen nib accommodation space is opened to allow the pen nib to protrude, and the writing instrument body is retracted and accommodated in the nib accommodation space. The front end opening of the space is closed.
The lid member may be a door that opens outward or inward by a hinge, or may be opened and closed in a shutter manner by rotating around the central portion of the member. A structure that seals from the inside of the tip opening of the nib housing space in contact with the inner edge of the opening, even when the internal pressure in the sealed chamber increases due to temperature changes, etc. This prevents the lid member from opening. Furthermore, if the center portion of the member is rotated, the radius of rotation can be minimized, which is convenient when the writing instrument itself is thin. In addition, in the case of sealing the nib accommodation space by the sliding contact part, the sliding contact part with respect to the other members of the writing instrument main body, at least one of the contacting parts in order to hermetically seal the nib accommodation space in a liquid-tight and airtight manner, It can be formed of synthetic resin, rubber, elastomer or the like. In particular, when it is made of butyl rubber, it is excellent in chemical resistance and gas resistance, so that it is sealed well. One or a plurality of sliding contact portions may be provided, and the sealing reliability can be improved by using a plurality of sliding contact portions.

As the hardly volatile liquid material disposed in the sliding contact portion, any material having a freezing point of −22 ° C. or lower, a boiling point of 145 ° C. or higher, and a viscosity of 10 to 500,000 MPa · s (20 ° C.) may be used. Soybean oil, rapeseed oil, corn oil, safflower oil, rice oil, cottonseed oil, sesame oil, peanut oil, olive oil Plant oils such as palm oil and the like. Synthetic lubricating oils include hydrocarbon-based synthetic lubricating oils such as Α-olefin (poly-Α-olefin), polybutene (polyisobutylene), alkylbenzene, and diester (dibasic acid ester). ), Fatty acid ester synthetic lubricating oil such as polyol ester (hindered ester), silicone oil, silicate ester, silane, etc. Silicone synthetic lubricating oils, fluorinated synthetic lubricating oils such as chlorofluorocarbons, perfluoropolyethers and fluoroesters, phenyl ethers and phosphoric acid esters. These can be used alone or in combination. Moreover, what gelatinized these may be used.
In particular, when synthetic resin, rubber, elastomer, or the like is used for the members that make up the sliding contact portion, it is chemically stable against solvents such as ink, and has releasability and non-adhesive properties. , Straight silicone oils such as polydimethylsiloxane, polymethylhydrogensiloxane, polymethylphenylsiloxane, and cyclic dimethylsiloxane that have low surface tension and are easy to spread on the surface of the material, and the side chain and / or both ends are modified with organic groups Amino modification, epoxy modification, carbinol modification, mercapto modification, carboxyl modification, methacryl modification, polyether modification, phenol modification, silanol modification, aralkyl modification, fluoroalkyl modification, long chain alkyl modification higher fatty acid ester modification, higher fatty acid content Modified silicone oil such as . In addition, straight silicone oils such as polydimethylsiloxane, polymethylhydrogensiloxane, polymethylphenylsiloxane, and cyclic dimethylsiloxane are less susceptible to environmental changes and the like because their viscosity changes with temperature are small.

The movement restricting portion for the hardly volatile liquid material is to prevent the hardly volatile liquid material from reaching the pen tip, and the diameter changing portion may be formed in an annular shape in the writing instrument body. By making the moving distance of the hardly volatile liquid material longer by the diameter changing portion, the hardly volatile liquid material is prevented from proceeding before the diameter changing portion. When the variable diameter portion has a step shape, the vertical cross-sectional shape can be variously adopted as a polygonal shape such as a triangle or a square, a circular shape, or a part of an elliptical shape. When the rising angle of the wall of the stepped portion is 90 ° or more, it is possible to make it more resistant to the expansion of the hardly volatile liquid material. Moreover, the movement control part with respect to a hardly volatile liquid substance may be one, or may be plural, and if it is made plural, the inhibitory effect can be acquired further.
Moreover, the movement control part with respect to a hardly volatile liquid substance should just be a pore which hold | maintains a hardly volatile liquid substance with capillary force. The forming method may be a method in which pores are provided between walls of two or more convex portions, or a minute gap is provided by grooves or concave portions. Capillary force can be expressed by the pores, and the hardly volatile liquid material can be accumulated by the capillary force, and the hardly volatile liquid material can be prevented from reaching the pen tip. The shape and size of the convex portion and the shape and depth of the groove and the concave portion can be set as appropriate. The size of the pores is appropriately set according to the surface tension of the hardly volatile liquid material, and the depth of the pores is appropriately set according to the coating amount of the hardly volatile liquid material.
Moreover, it may be formed continuously, or may be formed with a gap, and may be formed between the pen tip and the sliding contact portion. Can be obtained. Also, it may be a two-step gap with different widths, or it may be tapered so that the width gradually decreases as the depth increases, or it may be a multi-step gap in a staircase shape. The smaller the size, the greater the capillary force, and the more easily the non-volatile liquid material can be maintained in the pores.

  Further, the movement restricting portion for the hardly volatile liquid material may be one in which a large number of minute holes are arranged in an annular shape toward the axial center, or may be one in which a porous penetrating material is arranged in an annular shape. . Capillary force is expressed by the porosity, and the hardly volatile liquid material can be accumulated by the capillary force, and the hardly volatile liquid material is prevented from reaching the pen tip. In this case, the cross-sectional shape of the hole may be a circle, or a polygonal shape such as a triangle or a quadrangle, and the number and depth of the holes are appropriately set according to the application amount of the hardly volatile liquid material.

Moreover, even if the movement restricting portion for the hardly volatile liquid material is a portion where the arithmetic average roughness (Ra) is larger than that of the sliding contact portion, the movement restricting portion has an arithmetic average roughness ( Since Ra is a large portion, it spreads in the movement restricting portion for the hardly volatile liquid material, and the hardly volatile liquid material can be retained in the movement restricting portion for the hardly volatile liquid material. This suppresses the hardly volatile liquid material from reaching the pen tip. Examples of the method in which the movement restricting portion has a larger arithmetic average roughness (Ra) than the sliding contact portion include physical means and chemical means. As a physical means, it is possible to use a direct polishing paper or the like, blasting, or a resin-molded product obtained by blasting a die by blasting or the like. Moreover, as a chemical means, the method of attaching an etching process and microparticles | fine-particles to the surface is mentioned. In any case, the movement restricting portion may be a portion having an arithmetic average roughness (Ra) larger than that of the sliding contact portion, and may be used alone or in combination.
In addition, you may combine said method individually or in multiple numbers.

An example is shown in FIG.
A writing instrument body 2 is arranged in the exterior body 1 so as to be movable back and forth. The writing instrument body 2 is provided with a pen tip 3 at the tip, accommodates an occlusion body 4 in which ink is occluded at the back of the interior, and the rear end of the pen tip 3 is connected to the tip of the occlusion body 4 in an insertion shape. The rear end of the main body 2 is closed by a tail plug 5. The tail plug 5 is detachable by screwing with the writing instrument body 2 and is airtightly attached, so that the occlusion body 4 accommodated in the writing instrument body 2 can be replaced. In other words, the occlusion body 4 can be replaced when the ink is consumed, and the product can be used repeatedly without being disposable. Therefore, the waste is reduced, and it is environmentally friendly and economically useful. can do.

  The writing instrument body 2 includes a small-diameter portion 2a in which a pen-tip holder 6 with a nib 3 fixed by caulking is inserted at the tip, and a large-diameter portion 2b in which the occlusion body 4 is accommodated. There is a shoulder 2c between the small diameter portion 2a and the large diameter portion 2b. A plurality of ribs are formed between the shoulder portion 2c and the small diameter portion 2a to suppress the bending of the small diameter portion 2a.

  As shown in FIG. 2 which is an enlarged view of the I part of FIG. 1, the pen tip 3 is an extruded product made of a synthetic resin in which an ink passage is formed, and is caulked and fixed to a metal pen tip holder 6. The pen tip holder 6 is pressed into the tip hole of the writing instrument body 2 together with the pen tip holder 6. In addition, the air circulation groove | channel is formed in the front-end | tip hole inner side of the writing instrument main body 2 so that air exchange is possible. In addition, a step portion for determining the press-fitting position of the pen tip holder 6 is formed inside the tip hole of the writing instrument main body 2, and the step portion is used to make a fiber converging body different from the synthetic resin pen tip. The pen nib that can be inserted and fixed.

  A synthetic resin lid member 7 is arranged in the vicinity of the front end opening 1a of the exterior body 1. The lid member 7 is fixed in the exterior body 1 with a rotation shaft formed at a substantially central position of the member, and is disposed so as to be rotatable about the rotation shaft. The lid member 7 includes a lid portion 7a which is a sealed portion with an O-ring 8 made of butyl rubber disposed in the front end opening portion 1a of the exterior body 1, an open portion 7b through which a pen tip can pass, and a side surface portion 7c. ing. An inner projection 7d is formed on the inner side of the side surface portion 7c of the lid member 7, and an outer projection 7e is formed around the rotation axis on the outer side of the side surface portion 7c. The inner protrusion 7d of the lid member 7 is formed on the rear end side of the side surface portion 7c. An annular member 9 made of synthetic resin is disposed behind the lid member 7, and an elastic airtight member 10 made of butyl rubber is further disposed behind the lid member 7, and the elastic airtight member 10 and the annular member 9 are connected by abutment. ing.

  A coil spring 11 is disposed so as to cover the small diameter portion 2 a with one end abutting against the shoulder 2 c of the writing instrument body 2, and the writing instrument body 2 is urged backward by the coil spring 11. The other end of the coil spring 11 is in contact with the elastic airtight member 10, and the elastic airtight member 10 is biased forward by the elastic force of the coil spring 11. The elastic force to the front of the coil spring 11 is transmitted to the annular member 9 connected to the elastic airtight member 10 via the elastic airtight member 10, and is transmitted to the outer protrusion 7 e of the lid member 7. An outer circumferential contact portion 10a and a contact inclination preventing circumferential contact portion 10b are provided on the outer side of the elastic airtight member 10, and two inner circumferential contact portions 10c are provided on the inner side. The outer circumferential contact portion 10a is in contact with the inner wall surface of the exterior body 1 and the inner circumferential contact portion 10c is in contact with the outer peripheral surface of the small diameter portion 2a of the writing instrument body 2 to form a sliding contact portion.

  The sliding contact portion is coated with polydimethylsiloxane having a freezing point of −50 ° C. or less, a boiling point of 200 ° C., and a viscosity of 10,000 mPa · s (20 ° C.) as a hardly volatile liquid material. It achieves a low friction coefficient. In addition, a hardly volatile liquid material is disposed between the two formed inner circumferential contact portions 10c and between the outer circumferential contact portion 10a and the contact tilt prevention circumferential contact portion 10b. The sliding of the writing instrument body and the elastic airtight member is good. Even when the writing instrument main body 2 is moved back and forth repeatedly, a hardly volatile liquid material is supplied to the sliding contact portion, and the slidability is continuously maintained. In addition, since two (a plurality) of inner circumferential contact portions 10c of the elastic airtight member 10 are formed, the sealing with the small diameter portion of the writing instrument body is made more reliable. The circumferential contact between the O-ring 8 and the lid portion 7a of the lid member 7, the circumferential contact between the outer circumferential contact portion 10a of the elastic airtight member 10 and the inner wall surface of the exterior body 1, and the elastic airtight member 10 The inner peripheral contact portion 10c and the peripheral contact between the outer peripheral surface of the small diameter portion 2a of the writing instrument main body 2 maintain the pen tip in an airtight state. Further, since the elastic airtight member 10 is disposed at a position close to the lid member 7, the accommodation space of the pen tip 3 is made small, and the nib drying in the accommodation space is suppressed as much as possible. In particular, in the case of a thin nib, the size of the accommodation space of the nib greatly affects the drying of the nib in the accommodation space, so that the nib drying is more effectively suppressed.

  A locking projection 2d and a release projection 2e are formed behind the writing instrument body 2. A clip 12 is attached to the rear of the exterior body 1, and a gear member 13 is attached to the inside of the tip of the clip 12. The gear member 13 can be fitted into the locking protrusion 2d of the writing instrument body 2 through the hole 1b formed in the side wall of the exterior body 1. When the tail plug 5 is pressed, the writing instrument body 2 moves forward against the spring force of the coil spring 11. An inclined surface 2f is provided at the tip of the small diameter portion 2a of the writing instrument body 2, and the inclined surface 2f and the inner projection 7d provided on the inner side of the lid member 7 come into contact with each other, and the advancement of the writing instrument body 2 is received. The lid member 7 rotates around the rotation axis. In a state where the opening 7b of the lid member 7 and the tip opening 1a of the exterior body 1 are brought together, the contact between the inner projection 7d and the inclined surface 2f is released, and the inner projection 7d moves along the side surface of the small-diameter portion 2a. . The rotation of the lid member 7 stops and the open state is maintained. When the writing instrument main body 2 further advances, the pen tip 3 protrudes from the tip opening 1a of the exterior body 1. As the lid member 7 rotates, the outer protrusion 7e of the lid member 7 comes into contact with the end surface of the annular member 9, and the elastic airtight member 10 connected to the annular member 9 by contact with the annular member 9 includes a coil spring 11 It moves backward while resisting the resilience of. The inner projection 7d of the lid member 7 is formed on the rear end side of the side surface portion 7c, and the position where the inner projection 7d and the inclined surface 2f come into contact with each other can be positioned behind the side surface portion 7c of the lid member 7. Therefore, the length on the front side of the inclined surface 2f can be increased. That is, the internal space of the lid member 7 can be efficiently used as the accommodation space for the pen tip 3, and the pen tip protruding length can be maintained long. In addition, the diameter of the inner wall of the exterior body 1 is slightly larger from the rear than the portion in contact with the outer circumferential contact portion 10 a of the elastic airtight member 10. As the elastic airtight member 10 moves rearward as the lid member 7 rotates and opens, the outer circumferential contact portion 10a moves rearward while releasing contact with the inner wall of the exterior body 1. When the accommodation space of the nib 3 is closed by the lid member 7, the inner wall of the exterior body 1 and the elastic airtight member 10 are in close contact with the outer circumferential contact portion. Is larger in diameter from the rear than the portion of the elastic airtight member 10 that is in contact with the outer circumferential contact portion 10a, so that the elastic airtight member 10 and the inner wall of the exterior body 1 move backward. The sliding resistance can be further reduced. The contact inclination prevention circumferential contact portion 10b of the elastic airtight member 10 prevents the inclination when the elastic airtight member 10 moves rearward. When the pen tip 3 is projected, the locking projection 2d formed on the writing instrument body 2 and the gear member 13 are locked, and the protruding state of the pen tip 3 is maintained. When the tail plug 5 is pressed again, the writing tool main body 2 further advances, so that the release protrusion 2e formed on the writing tool main body 2 comes into contact with the gear member 13 and pushes it up, and the locking protrusion 2d and the gear member 13 are pushed up. The locked state is released. When the locked state is released, the writing instrument main body 2 moves rearward due to the elastic force of the coil spring 11, and the pen tip 3 is in an immersive state. By releasing the locked state, the writing instrument body 2 moves rearward, and the inner projection 7d separates from the surface along the small diameter portion 2a. At the same time, the elastic airtight member 10 moves forward due to the elastic force of the coil spring 11. To do. When the elastic airtight member 10 moves forward, the annular member 9 connected by contacting the elastic airtight member 10 also moves forward, and the elastic force of the coil spring 11 is outside formed on the outside of the lid member 7. This is transmitted to the protrusion 7e, and the lid member 7 is rotated in the opposite direction to that when the pen tip protrudes, and the front end opening 1a of the exterior body 1 is closed by the lid portion 7a of the lid member 7. At this time, the pen nib 3 is accommodated in the lid member 7, and the pen nib 3 does not come into contact with the rotating lid member 7 so that the pen nib is not damaged. In addition to butyl rubber, the O-ring 8 and the elastic hermetic member 10 include isobutylene rubber, butadiene rubber, styrene / butadiene rubber, nitrile rubber, chloroprene rubber, butyl rubber, ethylene propylene rubber, chlorosulfonated polyethylene, chlorinated polyethylene, acrylic rubber, Silicon rubber, acrylonitrile butadiene rubber, urethane rubber, fluoro rubber, epichlorohydrin rubber, polysulfide rubber, olefin-based thermoplastic elastomer, styrene-based thermoplastic elastomer rubber or elastomer can be exemplified and stored in the ink occlusion body It only needs to be excellent in chemical resistance to ink and gas permeability that affects sealing performance, but butyl rubber has excellent chemical resistance and gas permeability resistance, so it can seal well. . Butyl rubber is excellent in both chemical resistance and gas permeation resistance. Halogenated butyl rubber, in particular, has a small compression set, so that elastic deformation during sliding is easy to return to its original shape when stationary, and a good seal is achieved. And can be slid.

  In the front side portion of the writing instrument main body 2, an annular recess 2g is formed as a diameter change portion. The wall of the pen tip side of the recess 2g is formed of a hardly volatile liquid material when the hardly volatile liquid material travels along the outer peripheral surface of the writing tool body due to the back and forth movement of the writing tool body 2 or gravity and falls to the pen tip side. By increasing the moving distance, it functions as a movement restricting unit for the hardly volatile liquid material that suppresses the progression of the hardly volatile liquid material to the front. Furthermore, if the diameter on the pen tip side is made larger than the diameter on the rear side of the concave portion 2g, it is possible to further prevent the hardly volatile liquid material from flowing to the pen tip.

FIG. 4 shows another example. FIG. 5 shows an enlarged view of a portion II in FIG.
A writing instrument body 2 is disposed in the exterior body 1 so as to be movable back and forth. The writing instrument main body 2 includes a pen tip 3 at the tip, and houses an occlusion body 4 in which the coating liquid is occluded at the rear, and the rear end of the pen tip 3 is connected to the tip of the occlusion body 4 so as to be inserted. ing. Further, a clip portion 2h exposed outside the exterior body 1 from the side hole is formed on the rear outer side of the writing instrument main body 2, and a locking projection 2i is formed at the tip of the clip portion 2h. In accordance with the advancement and retraction of the writing instrument main body 2, the locking projection 2i of the clip part 2h is formed in the forward position locking recess 1c and the backward position locking recess 1d of the writing instrument body 2 formed on the side wall of the exterior body 1. Engage with each other to form a protruding state and a receiving state of the pen tip 3 from the front end opening 1a of the exterior body 1. In addition, an annular protrusion 1e is formed on the inner wall of the exterior body 1, and serves as a sliding contact portion with respect to the writing instrument body.

A lid member 7 is accommodated in the interior of the exterior body 1 in the vicinity of the front end opening. The lid member 7 circumferentially contacts the O-ring 8 made of butyl rubber disposed in the front end opening 1a of the exterior body 1 to close the opening 1a, and the annular protrusion 1e of the exterior body 1 and the writing instrument described above. The pen tip sealed chamber 14 is formed by the sliding contact portion with the outer peripheral surface of the main body.
The lid member 7 is fixed in the exterior body 1 by a rotation shaft (not shown) formed at a substantially central position of the member, and is arranged to be rotatable around the rotation shaft. Further, the lid member 7 has an abutting portion (not shown) with respect to the writing instrument main body 2, receives the advance of the writing instrument main body 2, rotates around the rotation axis, and the open portion of the lid member 7 is used as an exterior body. The nib sealing chamber 14 is opened together with the opening of the tip 1. Then, the writing instrument main body 2 moves forward, and the pen tip 3 is exposed from the tip opening 1a of the exterior body 1.

  The writing instrument body 2 has a small-diameter portion 2a on the front side that is a portion that accommodates the pen tip 3 as an outer shape and a large-diameter portion 2b that is a portion that accommodates the occlusion body 4, and a shoulder portion 2c is formed between the two. A coil spring 11 is disposed so as to cover one end of the shoulder portion 2c and cover the small diameter portion 2a. The other end of the coil spring 11 urges the lid member 7 via the spring receiving member 15, and the spring receiving member 15 and the lid member 7 have a contact portion (not shown). ing. When the writing instrument body 2 is retracted, the pressing force in the forward direction on the lid member 7 by the writing instrument body 2 is released. At this time, the elastic force of the coil spring 11 is exerted via the spring receiving member 15 and the contact portion. The lid member 7 is applied to the lid member 7, and the lid member 7 is rotated in the reverse direction to that when the opening portion 1 c is opened to return the opening portion 1 a to the closed state.

An annular protrusion 1e on the inner wall of the exterior body 1 abuts on an annular recess 2g formed on the outer wall of the writing instrument body 2 to form a sliding contact portion. The sliding contact portion is coated with polydimethylsiloxane having a freezing point of −50 ° C. or less, a boiling point of 200 ° C., and a viscosity of 10,000 mPa · s (20 ° C.) as a hardly volatile liquid material. Low friction coefficient of sliding is realized.
The annular recess 2g of the writing instrument body 2 has a wall part 2h on the longitudinal pen tip side and a wall part 2i on the rear side in the longitudinal direction, and when the writing instrument body 2 moves forward and backward from the exterior body 1, The annular protrusion 1e of the outer package 1 slides between the wall 2h and the wall 2i on the rear side in the longitudinal direction. The hardly volatile liquid material disposed in the sliding contact portion located in the concave portion 2g is difficult to travel to the pen tip side over the wall portion 2h as the convex portion. That is, the wall 2h functions as a movement restricting unit for the hardly volatile liquid material that suppresses the progress of the hardly volatile liquid material. Similarly, the rear wall 2i suppresses the progress of the hardly volatile liquid substance to the rear, and suppresses the situation where the hardly volatile solvent is insufficient in the sliding contact portion due to unnecessary wetting and spreading of the hardly volatile solvent. is doing.

Using the form used in the invention described in FIG. 1, a sample coated with various volatile liquid materials was used as a sample after the pen tip retracting operation was performed 1000 times.

(Check handwriting after pen tip movement)
A sample was written and the state of the handwriting was confirmed.

Since the sliding contact portion of the writing instrument main body also serves as a sealing portion, liquid-tightness and air-tightness are maintained near the mirror surface. Therefore, the arithmetic average roughness may be 0.5 to 5.0 μm, and preferably 0.5 to 3.0 μm.
In addition, the movement restricting portion of the hardly volatile liquid material preferably has an arithmetic average roughness of 10 μm to 30 μm. When the arithmetic average roughness of the sliding contact portion of the writing instrument body and the movement restricting portion of the hardly volatile liquid material is a combination of the above ranges, the movement restricting portion with respect to the hardly volatile liquid material wets and spreads, and the hardly volatile liquid material is removed. It can be made to stay in the movement control part with respect to a hardly volatile liquid substance. This suppresses the hardly volatile liquid material from reaching the pen tip.

The longitudinal cross-sectional view which shows an example. The enlarged view of the I section in FIG. FIG. 2 is a series of operation diagrams of pen tip protrusion / immersion in the example of FIG. 1. The longitudinal cross-sectional view which shows another example. The enlarged view of the II section in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Exterior body 1a Front opening 1b Hole 1c Recessed position locking recess 1d Retracted position locking recess 1e Annular protrusion 2 Writing tool body 2a Small diameter part 2b Large diameter part 2c Shoulder part 2d Locking protrusion 2e Release protrusion 2f Inclined Surface 2g Concave 3 Pen tip 4 Occlusion body 5 Tail plug 6 Pen tip holder 7 Lid member 7a Lid portion 7b Open portion 7c Side surface portion 7d Inner projection 7e Outer projection 8 O ring 9 Annular member 10 Elastic airtight member 10a Outer circumferential contact Part 10b Contact inclination preventing circumferential contact part 10c Inner circumferential contact part 11 Coil spring 12 Clip 13 Gear member 14 Clip 15 Gear member

Claims (4)

When the writing instrument main body with the tip of the pen is movably moved back and forth in the exterior body, and the writing instrument main body is moved back and forth so that the pen tip protrudes and immerses from the opening at the front end of the exterior body by operation, In a retractable writing instrument that slidably contacts, a refractory liquid material is interposed in the slidable contact portion, and a protrusion and recess that arranges a movement restricting portion for an annular refractory liquid material between the slidable contact portion and the pen tip. Formula writing instrument. The retractable writing instrument according to claim 1, wherein the movement restricting portion is an annular diameter changing portion. The retractable writing instrument according to claim 1 or 2, wherein the movement restricting portion for the hardly volatile liquid material is a pore for holding the hardly volatile liquid material by a capillary force. The intrusive writing instrument according to any one of claims 1 to 3, wherein the movement restricting portion for the hardly volatile liquid material is a portion having an arithmetic average roughness (Ra) larger than that of the sliding contact portion.