JP2012030374A - Writing material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To retract a ball pen refill vigorously by a biasing force of a coil spring when a rear end of a ball pen refill is detached from a front end portion of a rear member, and a front end surface of a feeding mechanism disposed on the rear member Clash with force.
Then, the ink in the ballpoint pen refill moves backward with respect to the ink containing cylinder by the impact force of the collision. As a result, the ink located near the tip of the ball-point pen tip also retreats, and there is a risk that writing blur will occur.
A shaft cylinder is formed by connecting a front shaft and a rear shaft, a core body is disposed in the shaft cylinder, the core body is urged rearward by a resilient member, and A writing instrument in which a rear end portion of the core is protruded from a rear end portion of the front shaft in a state where the front shaft and the rear shaft are separated from each other.
[Selection] Figure 1

Description

  In the present invention, a female screw is formed at the rear portion of the front shaft, a male screw that is screwed to the female screw is formed at the front portion of the rear shaft, and the front shaft and the rear shaft are screwed together to form a shaft cylinder, The present invention relates to a writing instrument in which a core body is arranged in the shaft cylinder and the core body is urged rearward by a resilient member.

  As an example, a ballpoint pen refill containing ink imparted with shear thinning is urged and arranged in the direction of the rear end of the shaft cylinder by a coil spring on the main body of the shaft cylinder having a front end opening. A knock having a cam groove on the inner wall surface, and a rear member mounted with a feeding mechanism composed of a knock body engaging with the cam groove and a rotating cam is detachably mounted on the shaft cylinder body by screw fitting. A knock-type ballpoint pen is known in which the rear end of the shaft cylinder body is positioned closer to the rear end side of the shaft cylinder than the rear end portion of the ballpoint pen refill.

JP 2003-63192 A

By the way, in the assembly of the above prior art, a coil spring is inserted into the shaft cylinder main body, then a ballpoint pen refill is inserted, and finally the rear member is screwed into the shaft cylinder main body.
However, when screwing the rear member into the shaft cylinder body, the front end portion of the rear member comes into contact with the rear end portion of the ballpoint pen refill, and the screw screwing operation is continued in a state in which the contact is maintained. There is a risk. Since the rear end of the ballpoint pen refill is located in the shaft cylinder body and is hidden, the rear end portion of the ballpoint pen refill cannot be seen, and often the rear end portion of the ballpoint pen refill is at the front end portion of the rear member. It will abut. This phenomenon becomes prominent when assembling with an automatic machine or the like. Since the shaft body is assembled in a state where it is laid sideways, the rear end portion of the ballpoint pen refill is bent downward by gravity, and the front end portion of the rear member comes into contact with the bent portion.
In this abutting state, the ball pen refill is advanced against the spring force of the coil spring at the front end portion of the rear member, so that the repulsive force from the coil spring is excessively applied to the ball pen refill. It will be.
As a result, when the rear end of the ballpoint pen refill is disengaged from the front end portion of the rear member, the ballpoint refill retreats vigorously due to the biasing force of the coil spring, and the front end surface of the feeding mechanism disposed on the rear member It will crash into you.
Then, the ink in the ballpoint pen refill moves backward with respect to the ink containing cylinder due to the impact force caused by the collision, and as a result, the ink located in the vicinity of the tip of the ballpoint pen tip also moves backward, resulting in writing blurring. There is a risk.

  Therefore, the present invention forms a shaft cylinder by connecting the front shaft and the rear shaft, arranges the core body in the shaft cylinder, and urges the core body toward the rear by the elastic member. In addition, the gist is that the rear end portion of the core body protrudes from the rear end portion of the front shaft.

  In the present invention, a shaft cylinder is formed by connecting a front shaft and a rear shaft, a core body is disposed in the shaft cylinder, the core body is urged rearward by a resilient member, and Since the rear end portion of the core is protruded from the rear end portion of the front shaft, it is possible to provide a writing instrument in which the ink does not retreat and the writing is not blurred.

The external view which shows a 1st example. The longitudinal cross-sectional view of FIG. FIG. The longitudinal cross-sectional view of FIG. FIG. 5 is a cross-sectional view of FIG. 4. FIG. 4 is a left side vertical sectional view of FIG. 3. The longitudinal cross-sectional perspective view of a press operation member and a tail plug. The external view of a press operation member and a tail plug. The longitudinal cross-sectional view of FIG. The longitudinal cross-sectional view which isolate | separated the axial cylinder and the tail plug. The longitudinal cross-sectional view which isolate | separated the axial cylinder and tail plug which show a 2nd example. The longitudinal cross-sectional view which shows a 2nd example. The longitudinal cross-sectional view which isolate | separated the axial cylinder and tail plug which show a 3rd example.

  The operation will be described. Since the rear end portion of the core body is exposed, the rear end portion can be easily guided into the rear shaft.

A first example will be described with reference to FIGS. This is a so-called retractable writing instrument in which a ball-point pen body is disposed in the shaft body and the ball-point pen body is disposed so as to be able to retract. A relatively soft resin material (soft member 2) is coated on the surface of the shaft tube 1 formed of a relatively hard resin material and gripped. As an example of a relatively hard resin material forming the shaft tube 1, polycarbonate is used in this example, but polyethylene terephthalate, acrylic, acrylonitrile butadiene styrene copolymer (ABS), acrylonitrile styrene copolymer Examples include coalescence (AS) and polypropylene. In order to improve the stability of a ballpoint pen body to be described later on the inner surface of the shaft tube 1, protrusions, vertical ribs, and the like may be formed radially on the inner surface of the shaft tube 1. Moreover, as a comparatively soft resin material which forms the soft member 2, although the thermoplastic elastomer is used in this example, soft acrylic etc. are mentioned.
The tail plug 3 is detachably attached to the rear end opening of the shaft tube 1 by a screwing means, but may be a fixing means using a press-fitting structure. A shaft body 4 is constituted by the shaft tube 1, the soft member 2, and the tail plug 3, and the vicinity of the tip of the shaft tube 1 is tapered toward the tip. The length of the shaft tube 1 in the longitudinal direction is three times or more that of the tail plug 3. That is, the attachment portion between the shaft tube 1 and the tail plug 3 is a rear portion of the soft member 2 that is a gripping portion. By providing it behind the part which holds each other's screwing part (attachment part), while preventing breakage from a screwing part, the mutual member is prevented from loosening. Incidentally, if the screwed part is gripped, that is, if it is positioned in the vicinity of the center of the shaft cylinder, there is a risk that the gripping force and writing pressure concentrate on the gripped part and break from the part. By forming the screw portion, the portion is in a thin state, so that it is easy to break. Moreover, if a gripping force is applied to the screwed portion, a force is also applied in the circumferential direction. As a result, the members are loosened, and writing feels uncomfortable. Further, inside the shaft body 4, the ball-point pen body 5 is disposed in a state of being urged rearward by an elastic member 6 such as a coil spring, but is moved back and forth with respect to the longitudinal direction of the shaft body 4. The tip of the ball-point pen body 5 (the ball-point pen tip 7) can be projected and retracted from the tip opening of the shaft body 4. The elastic member 6 is stretched between an outer surface step portion 5 a provided in front of the ballpoint pen body 5 and an inner surface step portion 1 a formed in front of the shaft cylinder 1.
Further, the vicinity of the rear end of the ball-point pen body 5 is located inside the shaft cylinder 1 while the elastic member 6 is compressed in a state where the tail plug 3 is screwed to the shaft cylinder 1. In a state where the stopper 3 is detached, the elastic member 6 is extended, and the vicinity of the rear end of the ballpoint pen body 5 is exposed from the rear end opening of the shaft tube 1. That is, the distance obtained by adding the distance A from the outer surface step portion 5a of the ballpoint pen body 5 to the rear end portion of the ballpoint pen body 5 and the free length distance B of the elastic member 6 is from the inner surface step portion 1a of the shaft tube 1 to the shaft tube. 1 is formed longer than the distance C to the rear end (see FIG. 10).
On the other hand, a rotor 8 is arranged inside the tail plug 3 so as to be movable back and forth, and a slider 9 is also arranged behind the rotor 8 so as to be able to move back and forth. The vicinity of the rear end of the child 9 is exposed from the rear end opening of the tail plug 3, and the exposed portion serves as the pressing operation portion 10. That is, when the pressing operation portion 10 of the slider 9 is pressed back and forth with a finger or the like, the ball-point pen body 5 in the shaft body 4 moves back and forth, whereby the ball-point pen tip 7 moves from the tip opening of the shaft body 4. It will appear. In addition, the rotor 8 is positioned substantially at the center of the tail plug 3, and the lower end surface of the rotor 8 is in contact with the rear end of the ballpoint pen body 5. Note that claw portions 8a are formed on the edge portion of the rotor 8 at four positions at equal intervals in the downward direction. The claw portions 8a are successively reduced in the rear and inward directions. is doing. By causing the cylindrical portion 8 a to inscribe the rear end portion of the ball-point pen body 5, shake and eccentricity at the rear end portion of the ball-point pen body 5 are prevented. That is, the rear end portion of the ball-point pen body 5 is also located at the substantially central portion of the tail plug 3.
Reference numeral 11 denotes a clip integrally formed with the tail plug 3, but it may be formed of a separate member and fixed to the tail plug 3 by means such as adhesion or press fitting.

The soft member 2 covers a recess 1B formed in a portion gripped by the shaft tube 1, and the shaft tube 1 and the soft member 2 are formed of different members, and the soft member 2 is a shaft tube. Although it is in a state of being inserted into 1, it may be integrally molded by means such as two-color molding. And the wave-shaped grip part 12 which has fine height is formed in the surface of the front part of the soft member 2, However, A plain shape may be sufficient or many dots are formed etc. You may do it. The soft member 2 can be easily inserted by applying alcohol to the inner surface of the soft member 2 or the surface of the shaft tube 1. And after inserting, the applied alcohol evaporates.
An internal thread 13 to which the tail plug 3 is screwed is formed on the inner surface of the rear portion of the shaft tube 1.

The tail plug 3 is composed of a large-diameter cylindrical portion 14 to which the base of the clip 11 is connected and a small-diameter cylindrical portion 15 formed in front of the large-diameter cylindrical portion 14. The portion 15 is formed with a male screw 16 and a guide tube portion 17 that are screwed into the female screw 13 of the shaft tube 1.
Here, a ball portion 11 a is formed in the front portion of the clip 11, and the ball portion 11 a is in contact with the surface of the shaft tube 1. That is, when a notebook, a pocket or the like is sandwiched between the clip 11 (ball portion 11a), it is difficult to come off.
Further, arc portions 11b are formed on both sides of the ball portion 11a. When replacing the ball-point pen body 5, the tail plug 3 is detached from the shaft body 4. At this time, since the tail plug 3 and the shaft body 4 are relatively rotated, the surface of the soft member 2 is formed by a ball portion 11a. There is a high risk of sliding scratches. In order to prevent the sliding scratches, arc portions 11b are formed on both sides of the ball portion 11a.

A jaw portion 18 for preventing the pressing operation portion 10 from falling off is formed at an intermediate portion of the inner surface of the tail plug 3, and the rear end surface of the jaw portion 18 is inclined downward toward the center. An inclined portion 18a is formed. By forming the inclined portion 24 a in the jaw portion 18, it is possible to easily insert the pressing operation portion 10 into the tail plug 3.
Further, a guide projection 19 is formed on the outer peripheral surface in front of the pressing operation portion 10, and the guide projection 19 is engaged with a notch portion 20 cut out in the axial direction of the jaw portion 18. By this engagement, the positioning of the pressing operation unit 10 with respect to the tail plug 3 is completed.
Here, when the pressing operation part 10 is pushed into the tail plug 3, the locking protrusion 21 formed on the side surface of the pressing member 10 bends toward the center so as to get over the jaw part 18. However, when the locking projection 21 is engaged with the through hole 22 formed on the side surface of the small diameter cylindrical portion 15 of the tail plug 3, the return is elastically restored by its own restoring force at the moment of engagement. 22 is locked. This prevents the pressing operation unit 10 from falling off the tail plug 3.
A finely textured satin portion 19 a is formed on the side surface of the guide projection 19. On the other hand, the inner surface of the notch 20 is a mirror surface 20a. The contact resistance is reduced as much as possible by bringing the matte portion 19a of the inner surface protrusion 19 into contact with the mirror surface portion 20a.

Further, by forming the through hole 22 in the male screw 16 formed in the small diameter cylindrical portion 15 of the tail plug 3, the small diameter cylindrical portion 15 in which the male screw 16 is formed is easily bent inward. . That is, when the tail plug 3 is screwed to the shaft cylinder 1 with an excessive force, the small diameter cylinder portion 15 is bent inwardly to cause idling, and the idling action causes the shaft cylinder 1 and the tail plug. 3 is prevented from breaking or breaking. Further, if the above-described amount of bending is sufficiently obtained, the tail plug 3 can be assembled by a linear press-fitting operation without rotating the tail plug 3 with respect to the shaft tube 1.
A cam portion 18b is formed on the front end surface of the flange portion 18, and the cam portion 18b includes a shallow groove portion 18c and a deep groove portion 18d. And the said notch part 20 is formed in the deep groove part 18d.
Below the inner surface of the tail plug 3, an inner surface rib 23 for preventing the rotor 8 from falling off is formed in a circumferential shape. A rear inclined surface 23a and a front inclined surface 23b are formed behind and in front of the inner rib 23, and the inclination angle of the rear inclined surface 23a is gentler than the inclination angle of the front inclined surface 23b. When the tail plug 3 is formed by means such as injection molding, the releasability of the core pin is made favorable.

  Next, a procedure for inserting the resilient member 6 and the ball-point pen body 5 into the shaft tube 1 and a procedure for assembling the tail plug 3 will be described. First, the bullet member 6 is inserted into the barrel 1 from the rear end opening, and then the front portion of the ballpoint pen body 5 is inserted into the bullet member 6 from the rear end opening. insert. At this time, the vicinity of the rear end of the ballpoint pen body 5 is exposed from the rear end opening of the shaft tube 1. Next, the tail plug 3 is screwed into the rear end opening of the shaft tube 1. At this time, the mounting operation of the ball pen body 5 near the rear end with respect to the guide tube portion 17 of the tail plug 3 can be visually confirmed. it can. In combination with this, in the state where the rear end portion of the ball-point pen body 5 is exposed, most of the ball-point pen body 5 is inserted into the shaft tube 1. Since it is located in the region, the ball-point pen body 5 is in a stable state without shaking with respect to the shaft tube 1. Therefore, the rear end portion of the ballpoint pen body 5 can be easily and straightly inserted into the guide tube portion 17 and can be brought into contact with the lower end surface of the rotor 8. When the tail plug 3 is attached to the shaft tube 1, the rear end portion of the ballpoint pen body 5 is located inside the shaft tube 1. After the mounting, the rear end portion of the ball-point pen body 5 is positioned inside the shaft tube 1 so that the rotor 8 can be positioned inside the shaft tube 1 and the tail plug 3 can be formed short. Accordingly, as described above, the screwing portion of each member can be positioned further rearward of the grip portion, and breakage or the like can be prevented.

  A second example will be described with reference to FIGS. This is an example in which the rear end of the ball-point pen body 5 protrudes from the rear end of the shaft tube 1 even when the tail plug 3 is fixed to the shaft tube 1. This will be specifically described below. In a state in which the shaft tube 1 and the tail plug 3 are detached, the elastic member 6 is extended, and the vicinity of the rear end of the ballpoint pen body 5 is exposed from the rear end opening of the shaft tube 1. Here, when the tail plug 3 is screwed and fixed to the shaft tube 1, the ballpoint pen body 5 moves forward while compressing the elastic member 6, but even when the screwing is completed, the rear end of the ballpoint pen body 5 is It is in a state of protruding from the rear end portion of the shaft tube 1.

A third example will be described with reference to FIG. This is an example in which a tail crown 24 is attached to the rear end portion of the ballpoint pen body 5. This will be specifically described. In the rear end opening of the ball-point pen body 5, a tail crown 24 is fitted in a press-fit state. In a state in which the shaft cylinder 1 and the tail plug 3 are detached, the rear end portion of the ballpoint pen body 5 is located inside the shaft cylinder 1, but the tail crown 24 attached to the rear end of the ballpoint pen body 5. The vicinity of the rear end is exposed from the rear end opening of the shaft tube 1. The tail cap 24 is used in this example to prevent the backflow prevention body 25 disposed inside the ballpoint pen body 5 from falling off, but even if it is a tail plug (for refilling). It may be a connecting part with a rotor or other members.
As in this example, by attaching the tail crown to the rear end of the ballpoint pen body, for example, when the shape of the product changes, by changing the tail crown, the conventional ballpoint pen body or A cam mechanism or the like can be used. As a result, a ballpoint pen body or a cam mechanism can be used in common, and the price as a product can be reduced.
In the above, three examples are shown. In any of the examples, the center of gravity of the ballpoint pen body is located in the axial tube region. When the shaft tube and tail plug are detached, the ballpoint pen body is prevented from easily falling off the shaft tube. Further, by providing the center of gravity of the ballpoint pen body within the region of the shaft cylinder, the ballpoint pen body can be easily inserted into the shaft cylinder.

DESCRIPTION OF SYMBOLS 1 Shaft cylinder 2 Resin material 3 Tail plug 4 Shaft body 5 Ball-point pen body 6 Repellent member 7 Ball-point pen tip 8 Rotor 9 Slider 10 Press operation part 11 Clip 12 Grip part 13 Female screw 14 Large diameter cylindrical part 15 Small diameter cylindrical form Part 16 Male thread 17 Guide tube part 18 Jaw part 19 Guide protrusion 20 Notch part 21 Locking protrusion 22 Through hole 23 Inner rib 24 Tail crown 25 Backflow prevention body

Claims (6)

A shaft cylinder is configured by coupling the front shaft and the rear shaft, and a core body is disposed in the shaft cylinder, and the core body is urged rearward by a resilient member, and the front shaft A writing instrument in which the rear end portion of the core is protruded from the rear end portion of the front shaft in a state where the front shaft and the rear shaft are separated. The writing instrument according to claim 1, wherein a connecting portion between the front shaft and the rear shaft is disposed behind the grip portion. The writing instrument according to claim 1, wherein the front shaft and the rear shaft are coupled by screwing. The writing instrument according to any one of claims 1 to 3, wherein the center of gravity of the core body is positioned in a region of a front axis. The writing instrument according to any one of claims 1 to 4, wherein an ink having shear thinning viscosity is contained in the core body. In the state where the front shaft and the rear shaft are separated, the rear end portion of the core body protrudes from the rear end portion of the front shaft, but in the state where the front shaft and the rear shaft are combined, The writing instrument according to any one of claims 1 to 5, wherein the end portion is located inside the front shaft.