JP2005193583A - Mechanical pencil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mechanical pencil which can be smoothly shrunk only by energizing in a linear electrically driven shape memory alloy 14 to deliver a core 6, has a simple structure, can be miniaturized, is smoothly actuated and can easily write. <P>SOLUTION: The mechanical pencil is self-heat-generated and contracted by energizing in the electrically driven type shape memory alloy 14, and a chuck 1 is forwarded by utilizing the contract of this electrically driven type shape memory alloy 14 to deliver the core 6. In addition, as a core guide 8 is retreated by abrasion of the core 6 to make a switch ON, and thus the alloy 14 is energized so that the core 6 is automatically delivered without any operation. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a mechanical pencil capable of performing writing by contracting a current-driven shape memory alloy when energized.

2. Description of the Related Art Conventionally, a mechanical pencil that feeds a lead by energizing using the power of a motor or a solenoid is known. (See Patent Documents 1 and 2)
Japanese Utility Model Publication No.57-23187 JP-A-53-79625

  The problem to be solved is that using a motor requires gears and cams, which makes the structure complicated and large, making it impossible to use for mechanical pencils. Also, those using solenoids have a complicated structure and become large, and the movement is not smooth, which is very troublesome for the writer.

  The first gist of the present invention is to perform expansion of the chuck for holding the core by the current-driven drive type memory alloy.

  The second gist of the mechanical pencil, in which the lead is drawn out by the advance of the chuck, is to perform the advance of the chuck by an energization drive type shape memory alloy.

  Further, a third gist is to provide a chuck that allows the lead to advance but prevents retraction, and causes the lead to protrude by an electrically driven shape memory alloy.

  Furthermore, the fourth gist is that the current-carrying shape memory alloy is composed of a Ti—Ni-based or Ti—Ni—Cu-based shape memory alloy that shrinks by self-heating when an electric current flows.

  Furthermore, the fifth gist is that the lead is worn and the lead guide is pushed against the paper surface and retracted, thereby energizing.

  Furthermore, the sixth aspect is that energization is performed by manually turning on the switch.

  Furthermore, the seventh gist is that the switch is turned on by energizing the lead with a force equal to or higher than the writing pressure and energized.

  Furthermore, the eighth aspect is that the lamp is turned on when the current-carrying shape memory alloy is energized.

  The mechanical pencil of the present invention can be smoothly contracted and fed out by simply energizing a linear shape memory alloy, so that the structure is simple and small, and the operation is smooth and easy to write.

  A mechanical pencil that can be drawn out simply by energizing it, has a simple structure and is small in size, has smooth operation, has little vibration, and is very easy to write.

  A first embodiment of the present invention will be described with reference to FIGS. 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10. In addition, let the left side of FIG. 1 be the front, and let the right side be the back. First, in FIG. 1, a fastening ring 2 is externally fitted to the head of the chuck 1, and the front portion of the lead tank 3 is press-fitted and fixed to the rear portion of the chuck 1. In addition, a chuck spring 5 is stretched between the connector 4 that receives the tightening ring 2 and the lead tank 3 with a load of about 100 g, and the chuck 1 is normally urged rearward in the longitudinal direction by the force of the chuck spring 5. The tapered surface formed on the head of the chuck 1 is pressed against the fastening ring 2 to be closed, and the core 6 is strongly held. The fastening ring 2 is configured to be appropriately slidable in the longitudinal direction between the front end inner collar 4A and the inner stage 4B of the connector 4. A cutout portion 4C is formed in the connector 4, and a piece 7A formed at the rear portion of the core 7 is located in the cutout portion 4C and protrudes rearward in the longitudinal direction. Further, the protrusion 3A of the core tank 3 is inserted into the opening window 7B formed in the piece 7A of the core 7. A slide terminal 7C of the switch A is formed at the rear portion of the piece 7A of the core 7, a contact 7D is formed at the intermediate portion of the slide terminal 7C, and the rear portion of the slide terminal 7C is elastically deformed outwardly to be contact 7E. Is formed. A core guide 8 is screwed into the front portion of the core 7, and a rubber core holder 9 extending in the longitudinal direction is incorporated inside the core guide 8. It is preferable to arrange the lead holder 9 as far as possible because the lead 6 can be used effectively.

  An inner shaft 11 is built in the shaft cylinder 10, and a base 12 is screwed onto the inner shaft 11, whereby the connecting tool 4 is held between the inner stage 12 </ b> A of the base 12 and the front end of the inner shaft 11. Further, the core guide 8 and the core 7 are configured to be slidable as appropriate within the base 12 and the inner shaft 11. A contact 11B is formed in the inner hole 11A of the inner shaft 11, and a contact 11D is formed in the rear inner hole 11C having a slightly larger diameter than the inner hole 11A. Further, the rear portion 11E of the inner shaft 11 is formed with a small diameter. The contacts 7D, 7E, 11B, and 11D constitute a switch A. When the lead guide 8 slides in the longitudinal direction, the contact 11D and the contact 7E come in contact with each other, and the switch A is turned on and off. Although the contact 7D and the contact 11B slide, they are always in contact. Usually, the switch A is OFF. A concave groove 3B is formed in the rear portion of the core tank 3, and a C-shaped ring 13 is fitted into the concave groove 3B. The C-shaped ring 13 has a C-shaped cross section and can be bent with a slight force, and the front portion is formed on the tapered surface 13A. A contact point 13B of the switch B is formed at the rear end of the C-shaped ring 13.

  Further, one end of the current-carrying shape memory alloy 14 made of a thin wire is fixed to the inner shaft 11, and the other end of the current-carrying shape memory alloy 14 is fixed to the sliding member 15. This energization drive type shape memory alloy 14 has a property of being overheated and contracted when a current flows. Specifically, Ti-Ni-based or Ti-Ni-Cu-based shape memory alloys are conceivable, and biometal BMF100, BMF150, BMF200 or BMF250 (manufactured by Toki Corporation) is preferable. A return spring 16 is stretched between the inner shaft 11 and the sliding member 15 with a load at the time of attachment of about 20 g. Furthermore, a terminal 17 is built in between the front inner collar 15A and the rear inner collar 15B of the sliding member 15, and a spring 18 is stretched between the rear end of the terminal 17 and the rear inner collar 15B. The load at the time of attaching the spring 18 is set larger than the load at the time of attaching the chuck spring 5 and the return spring 16. However, it is set to be weaker than the general writing pressure of 300 g. Further, a contact 17A of the switch B is formed at the front end of the terminal 17. The switch B is turned ON / OFF by connecting / disconnecting the contact 13B and the contact 17A. Normally, the contact 13B and the contact 17A are separated from each other as shown in FIG.

  A push member 19 is disposed at the rear portion of the lead tank 3 so as to be slidable in the shaft cylinder 10, and the inner flange 19 </ b> A of the push member 19 and the rear end of the lead tank 3 are configured to contact each other. Further, the inner flange 19A of the pressing member 19 is formed with an opening hole 19B through which the core 6 can pass. A connecting portion 19 </ b> C extending from the pressing member 19 is inserted through the opening window 10 </ b> A of the shaft tube 10 and is connected to the slide button 20. Locking projections 10B as shown in FIG. 4 are formed on both sides of the opening window 10A of the shaft cylinder 10. Further, a contact point 19D is formed at the rear end of the connecting portion 19C, and a contact point 10C is formed at the rear end of the opening window 10A. A main switch is formed by the contact point 19D and the contact point 10C.

  When the slide button 20 is slid back and forth, the connecting portion 19C moves back and forth with a moderate moderation by the locking projection 10B of the opening window 10A, and the contact 19D and the contact 10C are brought into and out of contact with each other. Is turned on and off. Normally, the connecting portion 19C is positioned in front of the locking projection 10B of the opening window 10A, and the contact 19D and the contact 10C are separated from each other.

  A case 21 is detachably attached to the rear inner side 10 </ b> D of the shaft cylinder 10, and a battery 22, a fuse 23 and an eraser 24 are provided in the case 21. Further, a knob 25 is detachably screwed to the rear outer side 10E of the shaft tube 10. As the battery 22, various commercially available batteries can be used. For example, one or a plurality of lithium batteries CR123A or CR2 for cameras, 1.5V AAA batteries, or rechargeable batteries can be used. It is conceivable to use a battery. Further, the shaft tube 10 is provided with a clip 26 and a lamp 27, and the lamp 27 is wired in parallel with the energization drive type shape memory alloy 14. As the lamp 27, various lamps such as an LED lamp, a wheat bulb or a miniature bulb can be considered.

  FIG. 5 is a wiring diagram of the mechanical pencil of the first embodiment.

  In order to perform writing from the state of FIG. 1, the slide button 20 is moved backward to bring the contact point 19D and the contact point 10C into contact, the main switch is turned on, and the state of FIG. When writing is performed in this state, the core 6 protruding from the core guide 8 is worn and pressed against the paper surface, and the core guide 8 moves backward. Then, the contact 7E of the switch A falls into the rear inner hole 11C, and the contact 7E comes into contact with the contact 11D, resulting in the state shown in FIGS. Accordingly, current flows through the current-carrying shape memory alloy 14 and the lamp 27, and the current-carrying shape memory alloy 14 contracts due to self-heating, and the lamp 27 is lit. When the energization drive type shape memory alloy 14 contracts, the sliding member 15 advances, the contact 13B and the contact 17A come into contact with each other, and the switch B is also turned on.

  Further, when the energization drive type shape memory alloy 14 contracts, the C-shaped ring 13 is pushed by the terminal 17. At this time, when the writing pressure is applied to the core 6, the chuck 1 cannot advance, and the spring 18 is compressed. When the lead 6 is released from the paper surface and the writing pressure of the lead 6 is released, the C-shaped ring 13 pushed by the terminal 17 moves forward together with the lead tank 3, the chuck 1 moves forward, and the lead 6 is fed out. Since the writer can confirm the extension of the lead 6 when the lamp 27 is lit, the writing can be interrupted immediately. When the chuck 1 further expands after the tightening ring 2 contacts the front end inner flange 4A of the connector 4 and the chuck 1 further advances, the lead guide 8 is pushed forward by the chuck 1 and the contact 7E of the switch A is moved to the rear. It rides on the inner hole 11A from the inner hole 11C, the contact 7E of the switch A is separated from the contact 11D, and the switch A is turned OFF, and the state shown in FIG. 3 is obtained. The force that the contact 7E of the switch A rides on the inner hole 11A is set larger than the lead holding force of the lead holder 9, so that the lead guide 8 does not advance only when the lead 6 advances. Therefore, the lead 6 protrudes from the tip of the lead guide 8 by a certain amount. In this state, since the switch B remains in the ON state, the chuck 1 and the core guide 8 further advance. Then, the C-shaped ring 13 comes into contact with the rear end of the rear portion 11E of the inner shaft 11, and the C-shaped ring 13 is contracted inward to be in the state shown in FIG. When the C-shaped ring 13 is contracted, the C-shaped ring 13 is detached from the terminal 17 and sinks into the terminal 17, and the chuck 1, the core tank 3 and the C-shaped ring 13 are retracted by the force of the chuck spring 5, and the chuck 1 is instantaneously formed. Is closed to the state shown in FIG. Then, the contact 13B of the C-shaped ring 13 and the contact 17A of the terminal 17 are separated from each other, and the switch B is turned OFF. Accordingly, the current flowing through the current-carrying shape memory alloy 14 is stopped and cooled, so that the current-carrying shape memory alloy 14 gradually expands. However, since the chuck 1 is already closed, writing is immediately performed. It can be carried out. The lamp 27 is turned off simultaneously with the switch B being turned off. As the energization drive type shape memory alloy 14 expands, the slide member 15 is retracted by the return spring 16, and the terminal 17 moves rearward from the C-shaped ring 13 to return to the state shown in FIG. The time until the energization drive type shape memory alloy 14 is completely extended is about 2 seconds after the switch B is turned OFF. When the lead 6 in use is consumed, when the chuck 1 moves forward, the next lead 6 follows and contacts the rear end of the shortened lead 6. As the chuck 1 moves backward, the protrusion 3A of the lead tank 3 comes into contact with the rear end edge of the opening window 7B of the core 7, and the lead guide 8 and the core 7 are slightly moved backward. Therefore, even if the core 6 is slightly retracted when the chuck 1 is closed, the core guide 8, the core holder 9 and the core 7 are also slightly retracted, so that the shortened core 6 and the next core 6 are in contact with each other. The state is maintained, and even if writing is performed as it is, the core 6 in writing does not bounce. If the follower core does not fall into the chuck 1, the chuck 1 is further retracted than when the core 6 is held. Therefore, the core 7 is also retracted together with the core tank 3, and the switch A is turned ON again. 6 is carried out. This feeding operation of the lead 6 is repeated until the next lead 6 falls into the chuck 1. When the writing is finished, the slide button 20 is advanced to turn off the main switch, and the chuck 1 is expanded by the push member 19 so that the lead 6 protruding from the lead guide 8 is immersed and brought into a portable state. In this state, even if the lead guide 8 is pushed and the switch A is turned on, unnecessary power is not supplied because the main switch is turned off.

  In the unlikely event that energization is performed due to a malfunction, and an excessive current flows through the energization drive type shape memory alloy 14, the current is cut off by the fuse 23. Although not shown, a means for forcibly pulling the pushing member 19 forward and turning off the main switch when the energization drive shape memory alloy 14 is contracted more than necessary can be considered. Further, when the battery 22 is replaced or the lead 6 is stored in the lead tank 3, the case 21 is removed from the shaft tube 10.

  Note that the switch B is effective for reliably energizing, but the core 6 can be extended only by the switch A if the energization drive shape memory alloy 14 can be instantaneously contracted. Various means known in the art can be used as means for retracting the core guide 8 as the chuck 1 is retracted. Furthermore, various conventionally known means can be used as means for disposing the lead holder 9 in the lead guide 8 as far forward as possible.

  In the first embodiment, when the lead 6 is worn by writing, the lead guide 8 is retracted, the switch A is turned on, the chuck 1 is advanced, and the lead 6 is fed out by a certain amount. Therefore, the writer can continuously write without any operation.

  A mechanical pencil according to a second embodiment of the present invention will be described with reference to FIGS. 11, 12, 13 and 14. First, in FIG. 11 and FIG. 12, a core guide 108 is built in the base 112 so as to be slidable in the longitudinal direction, and the core 6 is made of a rubber that holds the core 6 inside the tip hole 108A of the core guide 108 with an appropriate force. A second core holder 28 is configured. A follower tube 29 is built in the lead guide 108 so as to be slidable in the longitudinal direction, and a lead holder 109 for holding the lead 6 with a slightly stronger force than the second lead holder 28 is built in the follower tube 29. Further, a slide terminal 30 made of a conductive elastic piece is fixed to the core guide 108, and the slide terminal 30 is configured to be bent inward. Normally, the inner surface of the slide terminal 30 contacts the outer flange 29A of the follower tube 29, and the inward bending of the slide terminal 30 is restricted. Further, a contact 112B is formed on the inner surface of the base 112, and the contact 30A and the contact 112B of the slide terminal 30 are formed slightly apart from each other. The contact 30A and the contact 112B constitute a switch A.

  Next, a concave portion 101A is formed on the head of the chuck 101 whose front portion is divided by slitting. Metal balls 31 are respectively disposed in the recesses 101A. In addition, one end of the current-carrying shape memory alloy 114 is fixed to the rear portion of the follower tube 29, and the other end of the current-carrying shape memory alloy 114 is fixed to the tip locking portion 101B of the chuck 101. The energization drive type shape memory alloy 114 is preferably Biometal BMX150 (manufactured by Toki Corporation) in which a wire having a property of small tensile force but large shrinkage is wound in a coil shape.

  Further, a return spring 116 with a load of about 20 g to 30 g is stretched between the outer flange 29A of the follower tube 29 and the front surface of the chuck 101, and the current drive type shape memory alloy 114 is extended by the normal return spring 116. ing. A chuck spring 105 is stretched between the rear end of the fastening ring 102 fixed to the base 112 and the outer collar 101C of the chuck 101 with a force of about 10 g.

  The follower tube 29 is urged forward in the longitudinal direction by the force of the return spring 116, and the protrusion 29 </ b> B formed on the outer flange 29 </ b> A of the follower tube 29 is in contact with the locking step 112 </ b> C of the base 112. Further, the chuck 101 is urged rearward in the longitudinal direction by the force of the return spring 116 and the chuck spring 105, and the ball 31 disposed in the recess 101 A is pressed against the tapered surface 102 A of the fastening ring 102 and closed. The held core 6 is allowed to advance but is prevented from moving backward.

  The shaft cylinder 110 is screwed to the rear portion of the base 112, and a pressing member 119 is provided at the rear portion of the chuck 101. The pressing member 119 is configured to be able to contact the rear end of the chuck 101. In addition, a slide button 120 is integrally formed with the push member 119 by a connecting portion 119 </ b> C, and the slide button 120 protrudes from the opening window 110 </ b> A of the shaft tube 110. Further, locking projections are formed on both sides of the opening window 110 </ b> A of the shaft tube 110. A contact point 119D is formed at the rear end of the connecting portion 119C, and a contact point 110C is formed at the rear end of the opening window 110A. A main switch is formed by the contact point 119D and the contact point 110C. When the slide button 120 is slid back and forth, the connecting portion 119C moves with an appropriate degree of protrusion by the locking projection of the opening window 110A, and the main switch is turned on by the contact 119D and the contact 110C coming in and out. It is turned off. Normally, the connecting portion 119C is located in front of the locking projection of the opening window 110A, and the contact 119D and the contact 110C are separated from each other. Further, a rubber elastic body 32 is provided in the concave groove 110F of the shaft cylinder 110, and the outer casing 101C of the chuck 101 is configured to be in frictional contact with the elastic body 32.

  A plurality of spare cores 6 are accommodated in the shaft tube 110, and a case 21 is detachably attached to the rear inner side 110D of the shaft tube 110, and a battery 22, a fuse 23, and an eraser 24 are provided in the case 21. It is done. Further, the knob 25 is detachably screwed to the rear outer side 110E of the shaft tube 110. The shaft tube 110 is provided with a clip 126 and a lamp 27, and the lamp 27 is wired in parallel with the current-carrying shape memory alloy 114.

  FIG. 12 is a wiring diagram of the mechanical pencil of the second embodiment.

  In order to perform writing from the state of FIG. 11, the slide button 120 is moved backward to bring the contact 119D and the contact 110C into contact with each other, and the main switch is turned on. When writing is performed in this state, the core 6 protruding from the core guide 108 is worn, and the core guide 108 is moved backward by being pushed by the paper surface. The slide terminal 30 moves backward together with the lead guide 108, the contact 30A of the switch A comes into contact with the contact 112B, the switch A is turned on, and the state shown in FIG. Then, a current flows through the current-carrying shape memory alloy 114 and contracts due to self-heating. At the same time, a current flows through the lamp 27 and the lamp 27 lights up. When the energization drive type shape memory alloy 114 contracts, the force of the return spring 116 is released, but the chuck 101 is urged rearward by the chuck spring 105, so the follower tube 29 is first pulled backward. Then, since the inner surface of the slide terminal 30 is in contact with the outer flange 29 </ b> A of the follower tube 29, the core guide 108 also moves backward together with the follower tube 29. Then, the rear end of the slide terminal 30 comes into contact with the receiving step 112D. Then, since the frictional resistance of the outer terminal 29A of the slide terminal 30 and the follower tube 29 is set to be stronger than the force of the chuck spring 105, the chuck 101 is then advanced against the force of the chuck spring 105, and the chuck 101 is moved forward. Expanded to release the wick 6. When the head of the chuck 101 comes into contact with the stepped portion 112E of the base 112, the advancement of the chuck 101 is stopped and the outer collar 101C of the chuck 101 is brought into frictional contact with the elastic body 32.

  Further, when the current-carrying shape memory alloy 114 is contracted, the follower tube 29 is retracted again, and the outer flange 29A of the follower tube 29 is detached from the slide terminal 30. Then, the slide terminal 30 is bent inward, the contact 30A is separated from the contact 112B, the switch A is turned off, and the state shown in FIG. 14 is obtained. The current-carrying shape memory alloy 114 expands when no current flows, and the follower tube 29 is advanced by the return spring 116. Further, the lamp 27 is turned off when the switch A is turned off. At this time, the slide terminal 30 is pushed by the outer flange 29A of the follower tube 29 and moves forward together with the follower tube 29. However, since the slide terminal 30 moves forward while being bent inward, the switch A is in the OFF state. Is maintained. Therefore, the lead 6 is held by the lead holder 109 and the second lead holder 28 and advances together with the lead guide 108 and the follower tube 29. At this time, when the core 6 in use becomes short and comes off the chuck 101, the chuck 101 is expanded, so that the next core 6 falls into the chuck 101 and the rear end of the core 6 in use. Abut. When the lead guide 108 comes into contact with the front inner stage 112F of the base 112, the advancement is stopped, but the follow-up tube 29 further advances, and the outer collar 29A enters the inside of the slide terminal 30. At this time, the lead 6 held by the second lead holder 28 advances in the lead holder 109, and the lead 6 protrudes appropriately from the lead guide 108. Further, the chuck 101 is urged rearward by the return spring 116 and the chuck spring 105, but since the outer flange 101 </ b> C of the chuck 101 is in frictional contact with the elastic body 32, it is delayed from the advancement of the core guide 108 and the follower tube 29. Then, the chuck 101 is closed and the state shown in FIG. 11 is restored.

  Also in the second embodiment, when the lead 6 is worn by writing, the lead guide 108 is retracted and the switch A is turned ON, the lead guide 108 is further retracted, the chuck 101 is expanded, and the lead 6 is successively expanded. To pay out. Therefore, the writer can continuously write without any operation.

  A mechanical pencil according to a third embodiment of the present invention will be described with reference to FIGS. 15, 16, and 17. In addition, the same member as FIG. 1 attaches | subjects the same code | symbol, and abbreviate | omits the description. First, in FIG. 15, the core 107 is formed with a piece 107A and an opening window 107B. Further, the inner shaft 111 is formed with an inner hole 111A and a rear portion 111E. Further, a push button type switch A is provided in the gripping portion of the shaft tube 210. When the lead 6 is worn by turning on the main switch and performing writing, the switch A is turned on by pushing the push button 33 with a finger so as to be in the state shown in FIG. Is to energize. The lamp 27 is also lit. When the energization drive type shape memory alloy 14 contracts and the core 6 is fed out by a certain amount and the C-shaped ring 113 is detached from the terminal 117, if the pressing force of the push button 33 is released, the switch A is turned OFF and the current flows. The current drive type shape memory alloy 14 is extended, and the lamp 27 is turned off to return to the state shown in FIG. As shown in FIG. 16, in the switch A, the lower part of the rubber push button 33 is formed with a large diameter, and a conductive terminal 34 is attached to the inside thereof. Further, a contact point 35 and a contact point 36 are disposed below the terminal 34. When the push button 33 is pressed, the state shown in FIG. 17 is obtained, the terminal 34 comes into contact with the contact 35 and the contact 36, and the switch A is turned on.

  The wiring diagram is exactly the same as FIG.

  A mechanical pencil according to a fourth embodiment of the present invention will be described with reference to FIGS. In addition, the same member as FIG. 1 attaches | subjects the same code | symbol, and abbreviate | omits the description. A cushion spring 37 is stretched between the connector 104 that receives the tightening ring 2 and the inner shaft 211. The force of the cushion spring 37 needs to be stronger than the writing pressure, and the load at the time of attachment is set to 500 g. The connector 104 is configured to be appropriately slidable in the longitudinal direction between the inner stage 212 </ b> A of the base 212 and the front end of the inner shaft 211, but is normally urged forward in the longitudinal direction by a cushion spring 37. Further, a through hole 104D is formed in the connector 104, and a piece 7A of the core 7 is inserted into the through hole 104D.

  In order to perform writing from the state of FIG. 18, the slide button 20 is moved backward to bring the contact point 19D into contact with the contact point 310C of the shaft tube 310, the main switch is turned on, and writing is performed. When the lead 6 is worn, when the lead 6 is pressed with a force stronger than the writing pressure, the chuck 1, the tightening ring 2, and the coupling tool 104 are moved back against the force of the cushion spring 37 together with the lead 6. Then, the lead guide 8 and the lead holder 9 are moved back together with the lead 6, the contact 7E of the switch A falls into the rear inner hole 211C, and the contact 7E comes into contact with the contact 211D. When the switch A is turned on, a current flows through the current-carrying shape memory alloy 14 and the lamp 27 is turned on.

  By confirming the lighting of the lamp 27, the force that presses the lead 6 is released, but since the switch A is ON, the current-driven shape memory alloy 14 starts to contract and the switch B is also ON. As in Example 1, a fixed amount of core 6 is fed out.

  The wiring diagram is exactly the same as FIG.

  A fifth embodiment of the present invention will be described with reference to FIG. First, the core tank 103 is cut into a U shape to form an elastic piece 103C, and a protrusion 103D is formed on the elastic piece 103C. The protrusion 103D is formed with an inclined front surface and a vertical surface at the rear end, and a contact 103E is formed at the rear end of the protrusion 103D. A switch B is constituted by the contact 103E of the protrusion 103D and the contact 117A of the terminal 117. When the current-carrying shape memory alloy 14 contracts, the contact 103E of the switch B and the contact 117A come into contact with each other, the switch B is turned on, and the protrusion 103D of the lead tank 103 is pushed by the terminal 117, so that the lead tank 103 moves forward. When the lead tank 103 is appropriately advanced, the inclined surface of the protrusion 103D of the lead tank 103 is brought into contact with the rear end of the rear portion 11E of the inner shaft 11, the elastic piece 103C is bent inward, and the protrusion 103D enters the terminal 117. Other configurations are the same as those in the first, third, or fourth embodiment.

  A sixth embodiment of the present invention will be described with reference to FIG. First, the elastic piece 217B is formed on the terminal 217, and the inward projection 217C is formed on the elastic piece 217B. The front end of the inward projection 217C is a vertical surface, and an inclined surface 217D is formed in front thereof. A contact point 217A is formed on the vertical surface of the inward projection 217C. Further, a recess 203F is formed in the lead tank 203, and a contact 203E is formed in the recess 203F. The contact 203E and the contact 217A constitute a switch B. When the current-carrying shape memory alloy 14 contracts, the contact 203E of the switch B and the contact 217A come into contact with each other, the switch B is turned on, and the inner protrusion 217C of the terminal 217 causes the recess 203F of the core tank 203 to be turned on. The leading edge is pushed and the lead tank 203 moves forward. When the lead tank 203 is appropriately advanced, the inclined surface 217D of the terminal 217 comes into contact with the rear end of the rear portion 11E of the inner shaft 11, the elastic piece 217B bends outward, and the recess 203F of the lead tank 203 becomes the inward protrusion 217C of the terminal 217. It's something that goes inside. Other configurations are the same as those in the first, third, or fourth embodiment.

  A seventh embodiment of the present invention will be described with reference to FIGS. In addition, the same member as FIG. 1 attaches | subjects the same code | symbol, and abbreviate | omits the description. Although the current-driven shape memory alloy 14 can be instantaneously contracted due to self-heating, it takes about 2 seconds to cool and elongate. A warning lamp 38 is newly provided to notify the writer not to write until the chuck 1 is closed. First, in FIG. 22, a step portion 303G is formed in the core tank 303, and a contact 303H is formed in the step portion 303G. Further, a contact 317A is formed on the terminal 317. The contact 303H and the contact 317A constitute a switch B. Further, a lamp 27 for notifying normal lead feeding and a warning lamp 38 for notifying the movement of the chuck 1 are provided at the rear part of the shaft tube 410. For example, if the lamp 27 for notifying the lead is red, the warning lamp 38 is set to yellow.

  FIG. 23 is a wiring diagram of the seventh embodiment.

  In order to perform writing from the state of FIG. 22, the slide button 20 is moved backward, the main switch is turned on, and writing is performed. When the lead 6 is consumed, the lead guide 8 is retracted by the paper surface and the switch A is turned on. Accordingly, a current flows through the energization drive type shape memory alloy 14 and the warning lamp 38 that notifies the movement of the chuck 1 is turned on. The energization drive shape memory alloy 14 contracts due to heat generation, and the sliding member 15 and the terminal 317 move forward. When the terminal 317 contacts the step portion 303G of the lead tank 303, the switch B is turned on and the lead tank 303 moves forward. At this time, the warning lamp 38 that informs the movement of the chuck 1 is also turned on. When the lead tank 303 further advances, the lead 6 is fed out by the chuck 1. Further, the chuck 1 moves forward, the fastening ring 2 is removed from the chuck 1, and the lead guide 8 moves forward by being pushed by the chuck 1. Then, the switch A is turned OFF, the current flowing through the current-carrying shape memory alloy 14 is stopped, and the lamp 27 for notifying the lead out is turned off. Accordingly, the current-carrying shape memory alloy 14 is cooled and stretched, but it takes about 2 seconds to fully stretch. The chuck 1 and the core tank 303 are urged rearward by the chuck spring 5 and the sliding member 15 and the terminal 317 are urged rearward by the return spring 16. 14, the chuck 1 and the core tank 303 are retracted while the contact 303H and the contact 317A are in contact with each other. Since the chuck 1 is expanded for 2 seconds, writing cannot be performed, but during this time, the warning lamp 38 is turned on to inform the chuck 1 that it is moving. When the current-carrying shape memory alloy 14 is completely extended, the head of the chuck 1 is pressed against the fastening ring 2 and closed, the contact 303H and the contact 317A are separated, and the switch B is turned off. Then, the warning lamp 38 is turned off and the writing state is set, and writing can be performed again.

  In the seventh embodiment, the lamp 27 is not always necessary. Of course, if both are provided, writing can be performed more reliably.

  Further, in the above embodiment, when an excessive current flows through the current-carrying shape memory alloy, the current is cut off by the fuse. However, the present invention is not limited to the above embodiment, and the polyswitch Etc. may be used. For example, it is also conceivable to use a pulse heating drive current that stops the current for a minimum of 2 seconds when a current is applied for 1 to 3 seconds.

  Furthermore, a smaller battery can be used by using a method of discharging charges stored in a capacitor or the like in order to flow a large amount of current in the early stage when the switch A is turned on.

  Furthermore, when writing with the next lead coming into contact with the rear end of the shortened lead, as a means to support the shortened lead as forward as possible, or as a means to eliminate the gap between the shortened lead and the next lead Various means known in the art can be used.

  Further, in the above-described embodiment, the side button is advanced to expand the chuck in order to immerse the protruding core, but as a means to advance the chuck, a knob protruding from the rear end is pressed, It is also possible to perform by pressing the side button. Further, as means for turning the main switch on and off, it is conceivable that the knob protruding from the rear end is rotated or moved back and forth.

  Since the lead-out operation can be performed by the energization drive type shape memory alloy, the lead can be drawn out automatically or by a simple operation, and the structure can be simplified and the size can be reduced.

It is sectional drawing which shows the mechanical pencil of Example 1 of this invention. (Example 1) It is an expanded sectional view which shows the AA line of FIG. (Example 1) 3 is an enlarged cross-sectional view of a main part showing a switch A of Example 1. FIG. (Example 1) FIG. 3 is an enlarged cross-sectional view illustrating a main part of the main switch according to the first embodiment. (Example 1) FIG. 3 is a wiring diagram according to the first embodiment. (Example 1) It is principal part sectional drawing which shows the state which turned on the main switch in Example 1. FIG. (Example 1) It is principal part sectional drawing which shows the state in which the core was consumed in Example 1 and the switch A was set to ON. (Example 1) FIG. 3 is an enlarged cross-sectional view of a main part illustrating a state where a switch A is turned on in the first embodiment. (Example 1) In Example 1, it is principal part sectional drawing which shows the state by which the energization drive type shape memory alloy contracted and the core was let out. (Example 1) In Example 1, it is principal part sectional drawing which shows the state which the chuck | zipper retreated and the switch B was set to OFF. (Example 1) It is sectional drawing which shows the mechanical pencil of Example 2 of this invention. (Example 2) FIG. 6 is a wiring diagram in Example 2. (Example 2) It is principal part sectional drawing which shows the state in which the core was consumed in Example 2 and the switch A was set to ON. (Example 2) In Example 2, it is principal part sectional drawing which shows the state which the energization drive type shape memory alloy shrunk | retracted, the core was extended | stretched, and the chuck | zipper was expanded. (Example 2) It is sectional drawing which shows the mechanical pencil of Example 3 of this invention. Example 3 6 is an enlarged cross-sectional view illustrating a switch A of Example 3. FIG. Example 3 It is an expanded sectional view showing the state where switch A of Example 3 was set to ON. Example 3 It is sectional drawing which shows the mechanical pencil of Example 4 of this invention. (Example 4) It is an expanded sectional view which shows the AA line of FIG. (Example 4) It is principal part expanded sectional drawing which shows the mechanical pencil of Example 5 of this invention. (Example 5) It is principal part expanded sectional drawing which shows the mechanical pencil of Example 6 of this invention. (Example 6) It is sectional drawing which shows the mechanical pencil of Example 7 of this invention. (Example 7) FIG. 10 is a wiring diagram in Example 7. (Example 7)

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Chuck 6 core 8 core guide 14 Current drive type shape memory alloy 27 Lamp 101 Chuck 108 Core guide 114 Current drive type memory memory alloy

Claims (8)

  A mechanical pencil characterized in that the chuck for holding the core is expanded by a current-driven shape memory alloy.   A mechanical pencil in which a lead is drawn out by advancement of a chuck, wherein the advancement of the chuck is performed by an energization drive type shape memory alloy.   A mechanical pencil characterized by providing a chuck that allows the lead to advance but prevents retraction, and causes the lead to protrude with a current-driven shape memory alloy.   The current-carrying shape memory alloy is composed of a Ti-Ni-based or Ti-Ni-Cu-based shape memory alloy that shrinks by self-heating when an electric current is applied. The mechanical pencil according to item 1.   The mechanical pencil according to any one of claims 1 to 4, wherein the lead is worn and the lead guide is pushed against the paper and retracted to conduct electricity.   The mechanical pencil according to any one of claims 1 to 4, wherein energization is performed by manually turning on the switch.   The mechanical pencil according to any one of claims 1 to 4, wherein the switch is turned on by energizing the core with a force equal to or higher than the writing pressure, and energization is performed.   The mechanical pencil according to any one of claims 1 to 7, wherein the lamp is turned on when the energization drive type shape memory alloy is energized.

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