JP5489903B2 - mechanical pencil - Google Patents

Description

  The present invention relates to a mechanical pencil that can easily discharge a remaining core that can no longer be held by a chuck.

  Conventionally, the head part of the chuck is composed of a front taper part and a rear taper part, a middle piece is fixed to a guide pipe having a through window at an appropriate position, and a front tightening ring and a core holder are constructed in the base. The lead holder is recessed from the guide pipe through-hole that holds the center piece to hold the lead, and the return spring has a resilient force stronger than the guide pipe holding force of the lead holder provided between the base and the center piece. Thus, there is known a knock-type mechanical pencil constituted by abutting the middle piece against the front end of the chuck. (See Patent Document 1)

  However, the knock type mechanical pencil has a risk that the lead holder may be worn out and the next lead may be discharged.

Japanese Utility Model Publication No. 55-10726

  The problems to be solved are that the lead holder is rubbed and worn by the guide pipe, and that the next lead is discharged when the remaining lead is discharged.

  In the present invention, a lead holder is built in the tip member, and an expanding member is slidably disposed in the longitudinal direction at the rear of the lead holder, and the expanding member is urged rearward in the longitudinal direction by a spring, and a chuck And a fastener that is externally fitted to the chuck, a coupling that receives the fastener, and a chuck spring that biases the chuck rearward in the longitudinal direction. A return spring with a mounting load larger than the load is urged rearward in the longitudinal direction, and a pressing member interlocking with the connecting tool in the longitudinal direction is provided, and this pressing member is inserted in the sliding groove of the shaft cylinder so as to be slidable in the longitudinal direction. Then, an elastic piece is formed on the core holder, the core is held with an appropriate force by the elastic piece, and the core is fed out by pressing the core tank connected to the chuck. In both cases, the pressing member is pressed to advance the mechanism portion, the expanding portion presses the expanding member to advance, and the expanding member expands the elastic piece of the core holder so that it is not held by the chuck. The remaining core is discharged.

  The present invention can easily discharge a shortened remaining core that is not held by the chuck, improves the durability of the core holder, and may cause the next core to be discharged when the remaining core is discharged. There are no advantages.

FIG. 1 is a cross-sectional view showing a writing state of the mechanical pencil according to the first embodiment of the present invention. Example 1 FIG. 2 is a cross-sectional view illustrating a remaining core discharge state in the mechanical pencil according to the first embodiment of the present invention. Example 1 FIG. 3 is an enlarged cross-sectional view of the main part showing the remaining core discharge state of FIG. Example 1 FIG. 4 is a cross-sectional view showing a writing state in the mechanical pencil of Example 2 of the present invention. (Example 2) FIG. 5 is a cross-sectional view showing a writing state of the mechanical pencil according to the third embodiment of the present invention. (Example 3) FIG. 6 is a cross-sectional view showing a writing state in the mechanical pencil of Example 4 of the present invention. Example 4 FIG. 7 is a cross-sectional view illustrating a remaining core discharge state in the mechanical pencil according to the fourth embodiment of the present invention. Example 4 FIG. 8 is a cross-sectional view showing a writing state of the mechanical pencil according to the fifth embodiment of the present invention. (Example 5) FIG. 9 is a cross-sectional view showing a remaining core discharge state in the mechanical pencil according to the fifth embodiment of the present invention. (Example 5)

  A short pencil that can no longer be held by the chuck can be easily discharged, and a mechanical pencil that improves the durability of the lead holder has been realized.

  Hereinafter, the mechanical pencil according to the first embodiment of the present invention will be described with reference to FIGS. 1, 2, and 3. Moreover, let the left side of FIG. 1 be the front, and let the right side be back. First, the core holder 2 made of synthetic resin is press-fitted and fixed to the rear part of the metal guide pipe 1. An outer collar 2A is formed on the core holder 2 and three elastic pieces 2B extending rearward in the longitudinal direction are formed at equal intervals in the circumferential direction. Further, a front inner collar 3A is formed at the front end of the synthetic resin middle piece 3, and the front part of the middle piece 3 is formed in half by a kerf. Moreover, the metal expansion pipe 4 is fixed to the rear inner flange 3B formed at the rear end of the middle piece 3 so as to protrude forward from the rear inner flange 3B. The middle piece 3 and the expansion pipe 4 constitute an expansion member. The front inner collar 3A of the middle piece 3 is locked to the outer collar 2A of the core holder 2, and a spring having a mounting load of about 50 g between the outer collar 2A of the core holder 2 and the rear inner collar 3B of the middle piece 3 5 is attached and the middle piece 3 is urged rearward in the longitudinal direction. The guide pipe 1, the core holder 2, the middle piece 3, the expansion pipe 4 and the spring 5 are built in the tip member 6 so as to be slidable in the longitudinal direction.

  Further, a fastener 8 is externally fitted to the head portion 7A of the chuck 7 whose front part is divided into a plurality, and the fastener 8 is loosely fitted in the concave groove 9A of the connector 9 so as to be slidable in the longitudinal direction. A lead tank 10 is press-fitted and fixed to the rear part of the chuck 7, and a chuck spring 11 having an attachment load of about 300 g is attached between the front end of the lead tank 10 and the inner flange 9 </ b> B of the connector 9. Energize backward in the longitudinal direction. The head 7A of the chuck 7 urged rearward in the longitudinal direction is pressed by the fastener 8 and the chuck 7 is closed to hold the core 12 firmly. The fastener 8 is pressed against the inner collar 9B of the connector 9. A plurality of spare cores 12 are accommodated in the core tank 10 to constitute a mechanism unit.

  Furthermore, a sliding groove 13A that extends in the longitudinal direction and opens in the rear portion of the shaft tube 13 is formed. The mechanism portion is inserted from the rear side of the shaft tube 13, and the base portion 14 </ b> A of the clip 14 is inserted through the sliding groove 13 </ b> A of the shaft tube 13 and fixed to the connector 9. This clip 14 becomes a pressing member. Further, a return spring 15 having a mounting load of about 500 g is attached between the inner stage 13B of the shaft tube 13 and the outer stage 9C of the connector 9, and the mechanism part is urged rearward in the longitudinal direction, and the base part 14A of the clip 14 is provided. Is brought into contact with the rear end edge of the sliding groove 13A of the shaft tube 13. Further, the tip member 6 is detachably screwed to the front portion of the shaft tube 13, and a rubber grip 16 is provided between the tip member 6 and the outer stage 13 </ b> C of the shaft tube 13 so that a knock-type mechanical pencil is provided. Configure.

  The mechanical pencil performs writing in the state shown in FIG. When the lead 12 is fed out, the chuck 7 is advanced by pressing the lead tank 10 to feed out the lead 12. At this time, the attachment load of the return spring 15 is larger than the attachment load of the chuck spring 11, so that the connector 9 does not move forward. Accordingly, the fastener 8 together with the chuck 7 advances in the concave groove 9 </ b> A of the connector 9, and the core 12 is fed out.

  Further, when the core 12 is worn by writing and the core 12 has a length (remaining core) that cannot be held by the chuck 7, when the clip 14 as the pressing member is pressed, the return spring 15 is compressed. The mechanism moves forward. Then, the front end of the chuck 7 comes into contact with the rear end of the middle piece 3 to advance the middle piece 3. Then, the expansion pipe 4 moves forward together with the middle piece 3, the expansion pipe 4 is inserted into the elastic piece 2B of the core holder 2, and the elastic piece 2B is expanded to the remaining core discharge state shown in FIG. Then, when the tip of the writing instrument is directed downward, the remaining core held by the elastic piece 2B is dropped from the tip of the guide pipe 1 and discharged as shown in FIG. At this time, since the chuck 7 is closed, there is no possibility that the core 12 in the core tank 10 is dropped through the chuck 7. If the pressing of the clip 14 is released, the writing state shown in FIG. 1 is obtained. If the lead tank 10 is pressed in this state, the chuck 7 advances and the next lead 12 is followed. Moreover, since no remaining core remains in the core holder 2, the next core 12 is immediately followed and writing can be performed.

  Hereinafter, the mechanical pencil according to the second embodiment of the present invention will be described with reference to FIG. In addition, the same member as FIG. 1 attaches | subjects the same code | symbol, and abbreviate | omits the description. A slide groove 113A that extends in the longitudinal direction and is opened in the longitudinal direction is formed at the rear portion of the shaft tube 113, and a clip 114 is integrally formed with the shaft tube 113 at a position facing the slide groove 113A. The mechanism portion is inserted from the rear side of the shaft tube 113, the base portion 17A of the pressing member 17 is inserted into the sliding groove 113A of the shaft tube 113 and fixed to the connector 9, and the operation portion 17B of the pressing member 17 is connected to the shaft tube 113. Projects from the surface to form a knock-type mechanical pencil.

  When discharging the remaining core with the mechanical pencil, the operating portion 17B of the pressing member 17 is pressed to advance the mechanism portion, and the expansion pipe 4 expands the elastic piece 2B of the core holder 2.

  Hereinafter, the mechanical pencil according to the third embodiment of the present invention will be described with reference to FIG. In addition, the same member as FIG. 1 attaches | subjects the same code | symbol, and abbreviate | omits the description. A sliding groove 213 </ b> A is formed extending in the longitudinal direction from the rear end of the shaft cylinder 213. Further, a clip 214 as a pressing member is integrally formed at the rear portion of the connector 109 having the lead tank 110 built therein. The mechanism portion is inserted from the rear side of the shaft tube 213, and the base portion 214A of the clip 214 configured integrally with the connector 109 is inserted into the sliding groove 213A of the shaft tube 213. Further, the rear shaft 18 is screwed to the rear portion of the shaft cylinder 213, and the rear end of the connector 109 is brought into contact with the front end of the rear shaft 18 to constitute a knock type mechanical pencil.

  When discharging the remaining core with the mechanical pencil, by pressing the clip 214 as a pressing member, the return spring 15 is compressed and the mechanism part advances, and the expansion pipe 4 is the elastic piece 2B of the core holder 2. To expand.

  Hereinafter, the mechanical pencil according to the fourth embodiment of the present invention will be described with reference to FIGS. 6 and 7. In addition, the same member as FIG. 1 attaches | subjects the same code | symbol, and abbreviate | omits the description. A fastener 8 is externally fitted to the head portion 7A of the chuck 7 whose front portion is divided into a plurality, and the fastener 8 is loosely fitted in a concave groove 209A of the connector 209 so as to be slidable in the longitudinal direction. A connector 19 is press-fitted and fixed to the rear portion of the chuck 7, and an outer collar 19 </ b> A is formed on the connector 19. Further, a pipe-shaped core tank 210 is press-fitted and fixed to the rear portion of the connector 19. A chuck spring 111 having an attachment load of about 100 g is attached between the front end of the connector 19 and the inner flange 209B of the connector 209, and the chuck 7 and the core tank 210 are urged rearward in the longitudinal direction. The head 7A of the chuck 7 urged rearward in the longitudinal direction is pressed by the fastener 8 and the chuck 7 is closed to hold the core 12 firmly. Further, the fastener 8 is pressed against the inner collar 209B of the connector 209. A plurality of spare cores 12 are stored in the core tank 210, and a cylindrical weight body 20 is slidably provided on the outside of the core tank 210 to constitute a mechanism portion.

  Further, an inner collar 21A is formed in the middle portion of the inner shaft 21, a knock member 22 is inserted from the rear of the inner collar 21A, and a core 23 is inserted from the front of the inner shaft 21, and a center portion is inserted in the front portion of the knock member 22. The child 23 is press-fitted and fixed. Further, a rear spring 24 having an attachment load of about 150 g is attached between the inner flange 21A of the inner shaft 21 and the outer stage 22A of the knock member 22.

  Next, the mechanism portion is inserted from the rear of the shaft tube 313, the tip member 106 is detachably screwed to the front portion of the shaft tube 313, and a rubber is interposed between the tip member 106 and the outer casing 313D of the shaft tube 313. A grip 116 made of metal is provided. The mechanism portion is inserted from the rear side of the shaft tube 313, and the rear shaft 118 is detachably screwed to the rear portion of the shaft tube 313. Further, a return spring 115 having an attachment load of about 500 g is attached between the inner stage 313B of the shaft tube 313 and the outer stage 209C of the connector 209, and the mechanism is urged rearward in the longitudinal direction. Then, the outer flange 209D of the connector 209 is brought into contact with the front end of the inner shaft 21, and the rear end of the inner shaft 21 is brought into contact with the rear end inner flange 118A of the rear shaft 118. Further, the rear end of the lead tank 210 is appropriately separated from the inner collar 22B of the knock member 22. Further, the weight body 20 is loosely fitted between the outer casing 19A of the connector 19 and the front end of the core 23, and is slidable in the longitudinal direction.

  Further, the base 314 </ b> A of the clip 314 is inserted through the sliding groove 118 </ b> B of the rear shaft 118 and is fixed to the inner shaft 21. This clip 314 serves as a pressing member and constitutes a swing-out mechanical pencil.

  The mechanical pencil performs writing in the state shown in FIG. When the lead 12 is fed out, the chuck 7 is advanced by the inertial force of the weight body 20 generated by shaking the shaft tube 313 and the lead 12 is fed out.

  If the lead 12 is worn by writing and the lead 12 becomes a length (remaining lead) that cannot be held by the chuck 7, when the clip 314 as the pressing member is pressed, the inner shaft 21 moves forward. The front end of the inner shaft 21 presses the outer flange 209D of the connector 209 to compress the return spring 115, and the mechanism part advances. Then, the front end of the chuck 7 comes into contact with the rear end of the middle piece 3 to advance the middle piece 3. Then, the expansion pipe 4 moves forward together with the middle piece 3, the expansion pipe 4 is inserted into the elastic piece 2B of the core holder 2, and the elastic piece 2B is expanded to the remaining core discharge state shown in FIG. When the tip of the writing instrument is directed downward, the remaining core falls from the tip of the guide pipe 1 and is discharged. At this time, since the chuck 7 is closed, there is no possibility that the core 12 in the core tank 210 is dropped through the chuck 7. When the pressing of the clip 314 is released, the writing state shown in FIG. 6 is obtained. When the knock member 22 is pressed in this state, the inner flange 22B of the knock member 22 comes into contact with the rear end of the lead tank 210, and the chuck 7 advances by moving the lead tank 210 forward so that the next lead 12 is followed. . Moreover, since no remaining core remains in the core holder 2, the next core 12 is immediately followed and writing can be performed.

  Hereinafter, the mechanical pencil according to the fifth embodiment of the present invention will be described with reference to FIGS. 8 and 9. In addition, the same member as FIG. 1 attaches | subjects the same code | symbol, and abbreviate | omits the description. A rear inner collar 103B is formed at the rear end of the middle piece 103 constituting the expanding member, and an outer collar 103C is formed at the rear end of the middle piece 103. The expansion pipe 4 is fixed to the rear inner flange 103B. The middle piece 103 and the expansion pipe 4 constitute an expansion member. Further, the guide pipe 1, the core holder 2, the middle piece 103, the expansion pipe 4 and the spring 5 are incorporated in the tip member 206 so as to be slidable in the longitudinal direction. Further, the front end of the connector 309 is configured to be able to come into contact with the outer casing 103C of the middle piece 103 to constitute a knock type mechanical pencil.

  The mechanical pencil performs writing in the state shown in FIG. When the lead 12 is fed out, the chuck 7 is advanced by pressing the lead tank 10 to feed out the lead 12. At this time, since the attachment load of the return spring 15 is larger than the attachment load of the chuck spring 11, the connector 309 does not move forward. Accordingly, the fastener 8 together with the chuck 7 moves forward in the concave groove 309 </ b> A of the connector 309 and the core 12 is fed out.

  Further, when the core 12 is worn by writing and the core 12 has a length (remaining core) that cannot be held by the chuck 7, when the clip 14 as the pressing member is pressed, the return spring 15 is compressed. The mechanism moves forward. Then, the front end of the connector 309 comes into contact with the outer casing 103C of the middle piece 103, and the middle piece 103 is advanced. Then, the expansion pipe 4 moves forward together with the middle piece 103, the expansion pipe 4 is inserted into the elastic piece 2B of the core holder 2, and the elastic piece 2B is expanded to the remaining core discharge state shown in FIG. Then, the remaining core held by the elastic piece 2B is dropped from the tip of the guide pipe 1 and discharged. At this time, since the chuck 7 is closed, there is no possibility that the lead 12 in the lead tank 10 will pass through the chuck 7. If the pressing of the clip 14 is released, the writing state shown in FIG. 8 is obtained. If the lead tank 10 is pressed in this state, the chuck 7 advances and the next lead 12 is followed. Moreover, since no remaining core remains in the core holder 2, the next core 12 is immediately followed and writing can be performed.

  In addition, this invention is not limited to the said Example, Members, such as a shaft cylinder, a rear shaft, a tip member, a coupling tool, a core holder, a center piece, a guide pipe, a core tank, a clip, an inner shaft, a knock member, A plurality of members may be fixed and integrated.

  The present invention can be applied to a mechanical pencil that can easily discharge a short remaining core that is no longer held by the chuck and that does not cause the next core to be discharged when the remaining core is discharged.

2 core holder 2B elastic piece of core holder 2 5 spring 6 tip member 7 chuck 8 clamp 9 coupling tool 10 core tank 11 chuck spring 12 core 13 shaft cylinder 13A sliding groove of shaft cylinder 13 return spring 106 tip member 109 connection Tool 110 Core tank 111 Chuck spring 113 Shaft cylinder 113A Sliding groove 115 of shaft cylinder 113 Return spring 209 Connector 210 Core tank 213 Shaft cylinder 213A Sliding groove of shaft cylinder 213 313 Shaft cylinder

Claims (1)

  A lead holder is incorporated in the tip member, and an expansion member is slidably disposed in the longitudinal direction at the rear of the lead holder. The expansion member is urged rearward in the longitudinal direction by a spring, and the chuck and chuck A mechanism part is configured to include an externally fitted fastener, a coupling tool that receives the fastener, and a chuck spring that urges the chuck rearward in the longitudinal direction, and the mechanism part is mounted larger than the mounting load of the chuck spring. A pressing member that is urged rearward in the longitudinal direction by a return spring of the load and that is interlocked with the mechanism portion in the longitudinal direction is provided, and the pressing member is inserted into the sliding groove of the axial cylinder so as to be slidable in the longitudinal direction. Projecting from the surface, further forming an elastic piece on the core holder, holding the core with an appropriate force by this elastic piece, and pushing out the core tank by pressing the core tank connected to the chuck, By pressing the pressing member and moving the mechanism part forward, the expanding part is pressed and moved forward by the mechanism part, and the elastic piece of the core holder is expanded by the expanding member, and the shortened residue that is not held by the chuck Mechanical pencil characterized by discharging the lead.

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