JP5753663B2 - Ballpoint pen - Google Patents

Description

  The present invention relates to a ballpoint pen having a center core that is movable in the axial direction within a shaft cylinder.

  Conventionally, as a technology in such a field, there is JP-A-2001-301382. The writing instrument described in this publication is a knock-type ballpoint pen, and the core is protruded from the tip of the writing instrument by pressing the knock bar, and the core is stored in the writing instrument by pressing the clip. Further, the knock bar is provided with an elastic tongue piece formed by a U-shaped slit, and the protrusion provided on the elastic tongue piece is projected from a long window formed in the shaft tube, and Along with the movement, the protrusion moves in the long window. And when exchanging the core, this projection is once pushed down with a finger, and the knock bar is pulled out later, and the core is pulled out of the shaft tube together with the knock bar.

JP 2001-301382 A

  However, in the above-described conventional ballpoint pen, when replacing the center core, the protrusion of the elastic tongue must be pushed down with the finger of one hand and pulled out with the knocking stick picked up with the finger of the other hand. There is a problem that the replacement work of the lead becomes complicated.

  An object of this invention is to provide the ball-point pen which changed the center core easily.

The present invention relates to a ballpoint pen having a core that is movable in the axial direction within a shaft cylinder.
A shaft cylinder formed with a slit for replacing the core extending in the axial direction until reaching the rear end;
A core holder that is inserted into the shaft cylinder and holds the core, and
The core holder is
A front cylinder part;
A core mounting part for holding the core;
A slide part that protrudes from the window part formed in the shaft cylinder in front of the core replacement slit and is locked in the window part,
The front end of the core holder is provided with a helical coil spring formed integrally with the front cylinder ,
The center core mounting part includes a center core insertion hole into which the center core can be inserted,
The window part is characterized by communicating with the slit for replacing the core.

  This ballpoint pen can move the center core in a writable state and a retracted state by moving the center core holder inserted in the shaft tube in the axial direction. Since the core replacement slit extends until it reaches the rear end of the shaft tube, if the slide part continues to move backward along the core replacement slit from the window part, and the slide part continues to retract, The core can be pulled out from the rear end of the shaft tube together with the center core holder. In this way, at the time of exchanging the core, the core holder and the core can be extracted from the shaft tube by simply moving the slide along the core replacement slit without removing the finger hung on the slide. As a result, the core can be exchanged smoothly and easily.

Further, the slide portion is biased in the radial direction of the shaft tube, and the slide portion is aligned with the front end of the core replacement slit by moving the slide portion in the radial direction of the shaft tube. It is preferable that the insertion portion is formed to extend in the front-rear direction.
By adopting such a configuration, the slit insertion part of the slide part can be inserted into the slit for core replacement by moving the slide part in the radial direction of the shaft tube and moving it backward. However, the slide portion does not inadvertently move along the core replacement slit and come out of the rear end of the shaft tube.

In addition, it is preferable that the width of the core replacement slit is narrower than the width of the slit insertion portion of the slide portion.
By adopting such a configuration, the slit insertion portion can be moved with resistance in the slit for replacing the core, so that the core holder is vigorously moved together with the core from the rear end of the shaft cylinder. It is possible to avoid a situation that often pops out.

Further, it is preferable that an insertion opening that extends rearward is provided at the rear end of the core replacement slit.
By adopting such a configuration, the slit insertion portion of the slide portion can be easily inserted into the slit for exchanging the core from the rear end of the shaft tube, and the core can be replaced more smoothly and easily. In particular, the width of the core replacement slit is narrower than the width of the slit insertion portion, which is optimal when the slit insertion portion is inserted into the core replacement slit while expanding the width of the slit.

In addition, it is preferable that a guide portion that narrows toward the front is provided at the tip of the slit insertion portion of the slide portion.
When such a configuration is adopted, it is easy to insert the slit insertion portion of the slide portion into the slit after the replacement of the core, and the center can be replaced more smoothly and easily. In particular, the width of the slit for exchanging the core is narrower than the width of the slit insertion portion of the slide portion, which is optimal when the slit insertion portion is inserted into the slit for exchanging the core while expanding the width of the slit.
Further, it is preferable that the core mounting portion has a core pressing convex portion protruding so as to narrow the core insertion hole.

  According to the present invention, the core can be easily replaced.

1 is an exploded perspective view showing an embodiment of a ballpoint pen according to the present invention. It is a top view of the axial cylinder of the ball-point pen concerning the present invention. It is a front view of the axial cylinder of the ballpoint pen concerning the present invention. It is sectional drawing which follows the IV-IV line of FIG. 1 is a longitudinal sectional view of a ballpoint pen according to the present invention. It is a front view which shows a center core holder. It is sectional drawing which follows the VII-VII line of FIG. It is a longitudinal cross-sectional view which shows the ball-point pen of a writing state. It is sectional drawing which shows the state which pulled out the core holder from the axial cylinder for center core replacement | exchange. It is a transverse cross section showing the state where the slit insertion part was inserted in the slit for core replacement. It is sectional drawing which shows the state which inserts a slit insertion part from the rear end of the slit for core replacement | exchange.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of a ballpoint pen according to the present invention will be described in detail with reference to the drawings. In the following description, the pen tip side is referred to as “front side”.

  As shown in FIGS. 1 to 4, the ballpoint pen 1 has a shaft cylinder 2 made of resin (for example, polypropylene), and a core insertion hole 2 a is formed in the shaft cylinder 2. The loaded core 3 can be exchanged. Furthermore, the front half part of the shaft cylinder 2 has an outer diameter formed into a hexagonal cross section so that it can be easily gripped during writing and is difficult to roll on a desk or the like. Further, a clip 4 is integrally formed at the rear portion of the shaft tube 2.

  The shaft insertion hole 2a of the shaft cylinder 2 extends from the front end to the rear end of the shaft cylinder 2, and resin (for example, from the opening 2b of the rear end 2c of the shaft cylinder 2 is inserted into the center core insertion hole 2a. A core holder 6 made of (polyacetal) is inserted. The center core 3 is inserted into the center core holder 6 from the rear end side, and the rear end portion of the center core 3 is held by the center core holder 6.

  As shown in FIGS. 1, 5, and 6, at the rear end of the core holder 6, there is a core mounting portion 7 that enables the rear end of the core 3 to be held and the core 3 to be inserted and removed. Provided at the front end portion of the core holder 6 is a helical coil spring 5 that is integrally formed with the front cylindrical portion 8. The core mounting part 7 and the front cylinder part 8 are connected by a connecting piece 9 having an elastic restoring force and extending in the direction of the axis L, and the core mounting part 7, the front cylinder part 8 and the connecting piece 9 Thus, the holder body 10 is configured.

  The holder body 10 and the helical coil spring 5 are integrally formed of resin. As a result, the number of parts can be simplified, and as a result, the cost can be reduced.

  Further, by adopting the connecting piece 9 in the holder body 10, it is possible to reduce the weight of the core holder 6, and since the connecting piece 9 has elasticity, some warping occurs in the core holder 6. Even in this case, the center core holder 6 can be moved along the axis L smoothly and surely in the center core insertion hole 2a.

  The middle core mounting portion 7 protrudes so as to narrow the middle core insertion hole 7a in the rear side cylindrical portion 7b, and a rear side cylindrical portion 7b having a bottomed middle core insertion hole 7a that enables the insertion of the middle core 3. And a triangular core-shaped convex pressing portion 7c. The top of the center core pressing projection 7c extends perpendicular to the axis L and enables line contact with the center core 3. Accordingly, the core 3 can be securely held, and the core 3 can be easily inserted and removed during replacement.

  Further, the core holder 6 has an elastic arm portion 11 whose tip is fixed to the front cylinder portion 8 of the holder main body portion 10. The arm portion 11 extends opposite to the connecting piece 9, extends in the axis L direction in the shaft cylinder 2, and has an urging force directed outward in the radial direction of the shaft cylinder 2. . A slide portion 12 is formed at the free end of the arm portion 11 so as to protrude in the radial direction of the shaft tube 2.

  The slide portion 12 protrudes outward from a slit 13 formed in the shaft cylinder 2, and the slit 13 extends in the direction of the axis L. The slit 13 is provided with two rectangular extension parts 14 and 15 having a wide width (see FIG. 3).

  As shown in FIGS. 6 and 7, the side surface 12 a of the slide portion 12 is provided with a locking convex portion 17 formed by expanding the width of the sliding portion 12, and the locking convex portion 17 is an extension of the slit 13. The parts 14 and 15 enter the shaft cylinder 2 from the inside.

  A widened operation portion 20 is formed at the top of the slide portion 12, and a retaining portion 21 that extends in the longitudinal direction of the slide portion 12 with the same width as the locking projection 17 is formed at the bottom of the slide portion 12. Is formed. Then, the locking projection 17 projects toward the operation unit 20 in the retaining portion 21. In the locking projection 17 having a trapezoidal shape, an inclined surface 17a is formed on the front side, and a locking surface 17b substantially orthogonal to the axis L is formed on the rear side.

  Due to the inclined surface 17 a, the slide portion 12 can easily sink into the shaft tube 2 when the slide portion 12 advances from the extended portion 15 of the slit 13. The locking convex portion 17 of the slide portion 12 protruding from the extended portion 14 is securely locked by the locking surface 17 b coming into contact with the wall surface of the extended portion 14 of the slit 13.

  As shown in FIGS. 5 and 8, the tip of the helical coil spring 5 is pressed by a spring abutting portion 2d formed as a step portion in the shaft tube 2 when the core 3 is in a writing state (see FIG. 8). When the core 3 is in the retracted state, it is separated from the spring contact portion 2d in the shaft cylinder 2 (see FIG. 5). The free length of the spiral spring 5 is set to a length that creates such a state. Specifically, as shown in FIG. 8, the free length of the helical coil spring 5 is set slightly longer than the distance between the front end of the front cylinder portion 8 and the spring abutting portion 2d at the time of writing.

  When such a configuration is adopted, when the core 3 is in a writing state (see FIG. 8), the spring force of the helical coil spring 5 can be applied, so that the core 3 is loose in the shaft tube 2 at the time of writing. It is possible to eliminate discomfort during use. Further, when the core 3 is in the retracted state (see FIG. 5), since the helical coil spring 5 is not loaded, the helical coil spring 5 made of resin is difficult to sag. Even if 5 is molded with resin, the initial spring force can be maintained for a long time.

  Thus, the core holder 6 is not retracted by utilizing the elastic force of the helical coil spring 5, but the core holder 6 is retracted manually and the core 3 is retracted (see FIG. 5), the helical coil spring 5 is always in an unloaded state.

  The operation of the ballpoint pen 1 will be briefly described.

  As shown in FIG. 5, when the core 3 is in the retracted state, the rear end 12 b of the slide portion 12 comes into contact with the rear end 13 a of the slit 13, and the rear portion 12 a is moved by the elastic force of the arm portion 11 The locking convex part 17 of the slide part 12 protrudes from the extended part 15. In this state, the core 3 is not in a writable state unless the operation unit 20 is pressed.

  From this state, the operation unit 20 is pushed down with a finger, and the slide unit 12 is moved forward along the slit 13. At this time, the slide portion 12 sinks while the inclined surface 17a hits the front wall surface of the extension portion 15.

  When the operation unit 20 continues to advance further, the locking projection 17 completely sinks into the shaft tube 2, and then, as shown in FIG. 8, when the finger is moved away from the operation unit 20, the locking projection 17 is It protrudes from the extended portion 14 on the front side by the elastic force of the arm portion 11. Then, the locking surface 17 b is pressed against the wall surface of the extended portion 14 of the slit 13 by the spring force of the helical coil spring 5. Thereby, the retraction of the core 3 is restricted during writing, and the core 3 is not retracted by the writing pressure.

(Center exchange structure)
As shown in FIG. 3, the shaft cylinder 2 is provided with a core replacement slit 30 extending from the rear end 13 a of the slit (window) 13 to the rear end 2 c of the shaft cylinder 2. The slit 13 and the core replacement slit 30 communicate with each other, and the width of the core replacement slit 30 is narrower than the width of the slit 13. And since the width | variety of the slit 30 for center replacement | exchange is narrower than the width | variety of the slide part 12, the rear end 13a of the slit 13 is contact | abutted to the rear end 12b of the slide part 12, and the latching state of the slide part 12 is carried out. Is maintained.

  As shown in FIG. 7, FIG. 9 and FIG. 10, the slide portion 12 has a slit insertion portion 31 inserted into the core replacement slit 30 between the operation portion 20 and the locking projection 17. It extends in the front-rear direction along the bottom surface 20 a of the operation unit 20. The width of the slit insertion portion 31 is slightly smaller than the width of the core replacement slit 30. Therefore, unless the operation unit 20 is pushed back, the slide unit 12 does not easily enter the core replacement slit 30 and is not in the middle core replacement. It does not move out along the slit 30 and come out of the rear end 2c of the shaft cylinder 2.

  As shown in FIGS. 3 and 11, the width W <b> 1 of the core replacement slit 30 is narrower than the width W <b> 2 of the slit insertion portion 31. By adopting such a configuration, the slit insertion portion 31 can be moved with resistance in the core replacement slit 30, so that the center core holder 6 can be moved from the rear end 2 c of the shaft tube 2 to the center. It is possible to avoid a situation in which the core 3 jumps out vigorously.

  In addition, an insertion port 30a is provided at the rear end of the core replacement slit 30 so as to expand rearward. The opening angle of the insertion port 30a is about 30 degrees. When such a configuration is adopted, the slit insertion portion 31 can be easily inserted into the core replacement slit 30 from the rear end 2c of the shaft tube 2, and the core 3 can be replaced more smoothly and easily. In particular, the width W1 of the core replacement slit 30 is narrower than the width W2 of the slit insertion portion 31 of the slide portion 12, and while the width W1 of the center replacement slit 30 is expanded, the slit insertion portion 31 is moved to the center replacement slit. It is most suitable when inserted in 30.

  Further, a guide portion 31a that narrows toward the front is provided at the tip of the slit insertion portion 31, and the guide portion 31a is formed at the same angle as the opening angle of the insertion port 30a. When such a configuration is adopted, the slit insertion portion 31 can be easily inserted into the core replacement slit 30 from the rear end 2c of the shaft tube 2, and the core 3 can be replaced more smoothly and easily. In particular, the width W1 of the core replacement slit 30 is narrower than the width W2 of the slit insertion portion 31 of the slide portion 12, and while the width W1 of the center replacement slit 30 is expanded, the slit insertion portion 31 is moved to the center replacement slit. It is most suitable when inserted in 30.

  As shown in FIGS. 9 and 10, when replacing with the new core 3, the bottom portion 20 a of the operation portion 20 is pushed with a finger until the bottom portion 20 a contacts the shaft cylinder 2 against the spring force of the arm portion 11, and the slide portion 12 is pushed. The shaft cylinder 2 is moved in the radial direction. In this state, the rear end of the slit insertion portion 31 and the front end of the core replacement slit 30 are aligned. Then, when the operation unit 20 is retreated with a finger as it is, the slit insertion portion 31 is inserted into the core replacement slit 30, and the operation unit 20 is continuously retreated, whereby the opening 2 b of the rear end 2 c of the shaft tube 2. The core holder 6 can be extracted together with the core 3.

  Since such a ballpoint pen 1 extends until the core replacement slit 30 reaches the rear end 2c of the shaft cylinder 2, the slide portion 12 extends from the window portion (slit) 13 along the core replacement slit 30. If the slide part 12 continues to be moved backward as it is, the core 3 can be extracted from the rear end 2 c of the shaft tube 2 together with the core holder 6. In this way, at the time of exchanging the center core, the core holder 6 and the center core 6 and the center core 6 can be moved only by moving the operation unit 20 along the center core replacement slit 30 without removing the finger hung on the operation unit 20 of the slide unit 12. Since the core 3 can be extracted from the shaft cylinder 2, the middle core 3 can be replaced smoothly and easily.

  DESCRIPTION OF SYMBOLS 1 ... Ball-point pen, 2 ... Shaft cylinder, 2c ... Rear end of axial cylinder, 3 ... Center core, 5 ... Spiral coil spring, 6 ... Center core holder, 10 ... Holder main-body part, 11 ... Arm part, 12 ... Slide part, 12a: side surface of slide portion, 13 ... window portion (slit), 13a ... rear end of slit, 14, 15 ... expansion portion, 17 ... locking convex portion, 20 ... operation portion, 30 ... slit for replacing core, 30a ... insertion slot, 31 ... slit insertion part, 31a ... guide part, L ... axis, W1, W2 ... width.

Claims (6)

In a ballpoint pen having a center core that is movable in the axial direction within the shaft cylinder,
The shaft cylinder in which the slit for exchanging the core extending in the axial direction until reaching the rear end is formed;
A core holder that is inserted into the shaft cylinder and holds the core, and
The core holder is
A front cylinder part;
A core mounting part for holding the core;
A slide portion that protrudes from a window portion formed in the shaft cylinder in front of the slit for replacing the core and is locked in the window portion,
The front end portion of the core holder is provided with a helical coil spring formed integrally with the front cylinder portion ,
The core mounting portion includes a core insertion hole into which the core can be inserted,
The ballpoint pen, wherein the window portion communicates with the core replacement slit.   The slide portion is biased in the radial direction of the shaft cylinder, and the slide portion is aligned with the front end of the core replacement slit by moving the slide portion in the radial direction of the shaft cylinder. The ballpoint pen according to claim 1, wherein the slit insertion portion is formed to extend in the front-rear direction.   The ballpoint pen according to claim 2, wherein the width of the slit for exchanging the core is narrower than the width of the slit insertion portion of the slide portion.   The ballpoint pen according to claim 2 or 3, wherein an insertion port is provided at a rear end of the slit for exchanging the core so as to expand toward the rear.   The ballpoint pen according to any one of claims 2 to 4, wherein a guide portion that narrows toward the front is provided at a tip of the slit insertion portion of the slide portion.   The ballpoint pen according to any one of claims 1 to 5, wherein the core mounting portion has a center pressing convex portion protruding so as to narrow the core insertion hole.

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