JP5742434B2 - mechanical pencil - Google Patents

Description

  The present invention relates to a mechanical pencil in which a core feeding mechanism is disposed in a shaft cylinder and the core feeding mechanism is operated by a weight body disposed in the shaft cylinder.

Conventionally, a shaft feeding mechanism consisting of a chuck body, chuck ring (clamping ring), chuck spring, and core tank, and a weight body (pendulum) are arranged in the shaft cylinder (mechanical pencil body) so that it can be moved back and forth. There is known a mechanical pencil in which a chuck body is advanced by an inertial force of a weight body generated by shaking and a lead is drawn out.
Such a mechanical pencil has a disadvantage that the weight provided in the shaft cylinder moves back and forth due to unintentional vibration such as when it is carried, and the lead comes out. Various proposals have been made to solve this problem.
An example of the structure is a swing-out mechanical pencil having a structure that prevents the lead from unintended vibration by a structure that fixes the weight itself (Japanese Patent Laid-Open No. 2008-173953 (Patent Document 1)).

In the mechanical pencil described in Patent Document 1, a weight body having a length in the longitudinal direction of the shaft cylinder and provided with grooves on the entire circumference in the radial direction is provided in the shaft cylinder so as to be movable back and forth, and the weight. A lock lever having a lock portion that engages with the body and an operation piece having a pressing protrusion that presses the lock portion are incorporated in the shaft tube. When the operation piece is rotated while the weight body is stopped, the lock portion is pressed in the inner diameter direction of the shaft tube by the pressing protrusion of the operation piece and deformed. And it falls into the groove dug in the weight body, and as a result, the weight body is fixed and the unwinding of the core due to unintended vibration is prevented.
In Patent Document 1, an engagement claw is provided on each of the lock portion and the operating body, and the engagement claw is engaged. When unlocking the weight body, i.e., when using a mechanical pencil, by rotating the operating body in the opposite direction to the locking state, the locking part is engaged with the operating body by the engaging claw. It is moved in the outer diameter direction of the shaft tube. At this time, the engagement between the weight body and the lock portion is released, and the weight body can be moved back and forth, so that a normal lead feeding operation can be performed.

JP 2008-173953 A

  In the prior art described in Patent Document 1, since the weight body is locked by deforming the lock portion of the lock lever, a load is applied to the lock portion. For this reason, there has been a high possibility that the lock of the weight will fail due to cracks in the lock of the weight or break of the lock due to long-term use.

The present invention is a mechanical pencil in which a core feeding mechanism is disposed in a shaft cylinder having a front shaft and a rear shaft, and the core feeding mechanism is operated by a weight body disposed in the front shaft, the shaft is fixed to the fixing member, the eggplant from the weight body or any one of a part at least magnets of the fixed member, without at least a magnet or ferromagnetic part of the other, said fixed and said weight body When the member is disposed at the opposing position, the weight body and the fixing member can be fixed by magnetic force, and when the weight body and the fixing member are disposed at the non-facing position, the weight body and The first gist is that the fixing member can be released. A front shaft and a cap for the front shaft are provided, a core feeding mechanism is disposed in the front shaft, and the core feeding mechanism is disposed in the front shaft. The shaft actuated by the weight body A fixed member is fixed to the cap, and a part of either the weight or the fixing member is made of at least a magnet, and the other part is made of at least a magnet or a ferromagnetic material, The cap and the fixing member can be switched between a facing position and a non-facing position by enabling the cap to be attached to and removed from the front and rear of the front shaft, and the weight and the fixing member are opposed to each other. The weight body and the fixing member can be fixed by a magnetic force when arranged at a position, and the weight body and the fixing member are arranged when the weight body and the fixing member are arranged at a non-opposing position. The second gist is that the can be canceled .

The present invention is based on the first aspect, in which a mechanical pencil is arranged in a shaft cylinder having a front shaft and a rear shaft, and the core feeding mechanism is actuated by a weight body disposed in the front shaft. a is, the rear shaft is fixed to the fixing member, the eggplant from the weight body or any one of a part at least magnets of the fixed member, without at least a magnet or ferromagnetic part of the other, When the weight body and the fixing member are arranged at the opposing positions, the weight body and the fixing member can be fixed by a magnetic force, and when the weight body and the fixing member are arranged at the non-opposing positions. The weight body and the fixing member can be released, and the second gist is to have a front shaft and a cap of the front shaft, arrange a core feeding mechanism in the front shaft, and Actuated by a weight disposed in the front shaft It is a mechanical pencil, and a fixing member is fixed to the cap. A part of either the weight body or the fixing member is made of at least a magnet, and the other part is made of at least a magnet or a ferromagnetic material. The weight and the fixing member can be switched between a facing position and a non-facing position by making the cap detachable from the front and rear of the front shaft, and the weight and the fixing member are The weight body and the fixing member can be fixed by a magnetic force when arranged at the opposing position, and the weight body and the fixing member when the weight body and the fixing member are arranged at a non-opposing position. Since it can be released , the weight can be locked well over a long period of time.

BRIEF DESCRIPTION OF THE DRAWINGS It is an external view of the whole mechanical pencil of 1st Example. FIG. 2 is an exploded perspective view of FIG. 1. FIG. 2 is a longitudinal sectional view of FIG. 1 (at the time of releasing the weight body). FIG. 4 is a longitudinal sectional view of FIG. 1 in which the cross-sectional position is 90 degrees different from that of FIG. FIG. 4 is a sectional view taken along line AA in FIG. 3. FIG. 4 is a sectional view taken along line BB in FIG. 3. It is CC sectional view taken on the line of FIG. FIG. 6 is an enlarged perspective view of a front part of a rear shaft 4. 2 is an enlarged perspective view of a rear part of a front shaft 3. FIG. It is a longitudinal cross-sectional view (when fixing a weight body) of FIG. It is an external view (at the time of releasing fixation of a weight body) of the whole mechanical pencil of 2nd Example. FIG. 12 is a longitudinal sectional view of FIG. 11 (at the time of releasing the weight body). FIG. 13 is an enlarged partial rear view of FIG. 12. It is an external view (at the time of fixation of a weight body) of the whole mechanical pencil of 2nd Example. FIG. 15 is a longitudinal sectional view of FIG. 14 (when the weight body is fixed). FIG. 16 is a rear partial enlarged view of FIG. 15. It is an external view (at the time of releasing fixation of a weight) of the whole mechanical pencil of 3rd Example. FIG. 18 is a longitudinal sectional view of FIG. 17 (at the time of releasing the fixing of the weight body). FIG. 19 is an enlarged partial rear view of FIG. 18. It is an external view (at the time of fixation of a weight body) of the whole mechanical pencil of 3rd Example. FIG. 21 is a longitudinal sectional view of FIG. 20 (when the weight body is fixed). FIG. 22 is an enlarged view of the front part of FIG. 21.

The operation will be described. A mechanical pencil in which a core feeding mechanism is disposed in a shaft cylinder having a front shaft and a rear shaft, and the core feeding mechanism is actuated by a weight body disposed in the front shaft, and is fixed to the rear shaft. the member is fixed, together with the forms from the weight body or any one of a part at least magnets of the stationary member, and at least without a magnet or a ferromagnetic material, said fixing member and said weight body part of the other face The weight body and the fixing member can be fixed by a magnetic force when arranged at a position, and the weight body and the fixing member are arranged when the weight body and the fixing member are arranged at a non-opposing position. In addition, it has a front shaft and a cap for the front shaft, and a core feeding mechanism is arranged in the front shaft, and the core feeding mechanism is operated by a weight body arranged in the front shaft. It ’s a mechanical pencil A fixing member is fixed to the cap, and a part of either the weight body or the fixing member is made of at least a magnet, and the other part is made of at least a magnet or a ferromagnetic material. The weight body and the fixing member can be switched between a facing position and a non-facing position by being detachable from the front and rear of the shaft, and the weight body and the fixing member are arranged at the facing position. In some cases, the weight body and the fixing member can be fixed by magnetic force, and the weight body and the fixing member can be released when the weight body and the fixing member are disposed at non-opposing positions. The weight is fixed by a magnetic force (attraction) acting between the weight and the fixing member. Accordingly, the weight body can be fixed without applying a load to the components related to the fixing of the weight body and without causing excessive deformation. As a result, the weight body can be fixed well over a long period of time.
In the present invention, the lead feeding mechanism has at least a chuck body, a chuck ring, a chuck spring, and a lead tank.

  The specific configuration of the first embodiment of the present invention will be described below with reference to FIGS. The shaft cylinder 1 is fitted to a front member 2, a front shaft 3 that is detachably screwed to the rear end of the front member 2, and a rear end of the front shaft 3 that is rotatably attached to the front shaft 3. And a rear shaft 4.

Inside the shaft tube 1, a lead feeding mechanism for feeding the lead L is disposed so as to be movable back and forth. In this embodiment, the lead feeding mechanism is unitized, and hereinafter referred to as a lead feeding unit 5. The core feeding unit 5 will be described in detail.
A core tank 6 for storing a plurality of cores L is disposed in the shaft cylinder 1 so as to be movable back and forth. A chuck body 7 for holding and opening the cores L is disposed in front of the core tank 6. It is fixed. A chuck ring 8 that opens and closes the chuck body 7 is surrounded by a front outer periphery of the chuck body 7. In addition, a slide member 9 that slides in the tip member 2 is disposed in front of the chuck body 7 so as to be movable back and forth, and the lead L that is fed out is retracted inside the slide member 9. A core detent member 10 made of a rubber-like elastic body to be blocked is fixed. Further, an elastic body 11 made of an O-ring or the like for providing a sliding resistance with the tip member 2 is disposed on the outer periphery of the slide member 9. Reference numeral 12 denotes a core having a large-diameter collar on the front side, and the core 12 is disposed so as to cover the chuck ring 8. The flange portion of the core 12 is sandwiched between the tip member 2 and the front shaft 3, and the lead feeding unit 5 is positioned in the front shaft 3. Reference numeral 13 denotes an elastic member such as a coil spring that urges the core tank 6 and the chuck body 7 backward. The elastic member (chuck spring) 13 includes the core 12 and a weight body 14 described later. Is stretched between the receiving member 15 and the receiving member 15. The weight body 14 is housed in the front shaft 3 so as to be movable back and forth, and the receiving member 15 of the weight body 14 is fixed to the outer peripheral portion of the connecting portion between the core tank 6 and the chuck body 7. An eraser receiving member 16 is fitted into the rear end of the core tank 6, and an eraser 17 is detachably attached to the rear end portion of the eraser receiving member 16. Reference numeral 18 denotes a knocking member which is detachably attached to the eraser receiving member 16 and is arranged at the rear portion of the rear shaft 4.
When the shaft cylinder 1 is swung in the vertical direction, the weight body 14 in the shaft cylinder 1 moves back and forth, and by applying a forward force to the receiving member 15, the chuck body 7 moves forward and the core L is drawn out. .
The lead L can be extended by pressing the knock member 18 downward.

Next, the structure related to the weight body 14 and the fixation / release of the weight body 14 will be described in detail.
Inside the front shaft 3, there is formed a fan-shaped housing portion 19 having a fan-like cross section every 90 degrees, penetrating in the longitudinal direction, and each of the weight housing portions 19 has a fan-like cross section. The weight body 14 is accommodated so as to be movable back and forth with respect to the front shaft 3 (FIGS. 5 and 6). In this embodiment, the weight body 14 is composed of an iron member 20 and a magnet 21 fixed to the rear end portion of the iron member 20, and the iron member 20 and the magnet 21 are fixed by adhesion ( FIG. 3).
On the other hand, inside the rear shaft 4, a fan-shaped shape fixing member storage portion 22 corresponding to the weight storage portion 19 of the front shaft 3 is formed every 90 degrees. A fixed magnet (fixed member) 23 having a fan-shaped cross section is fixed to the lower end of the fixed member storage portion 22 of the rear shaft 4 (FIGS. 4 and 7). The magnets 21 in the front shaft 3 are arranged such that the surfaces facing each other when the magnets are arranged at opposing positions are different magnetic poles.
Here, as described above, the rear shaft 4 is rotatably fitted to the front shaft 3. The front shaft 3 and the rear shaft 4 are fitted by a rib portion 24 formed at the front end of the rear shaft 4. More specifically, four leg portions 25 that are evenly arranged in the radial direction extend in front of the outer peripheral portion of the rear shaft 4. The front end of the leg portion 25 is an arrow-shaped rib portion 24 that is convex in the outer diameter direction (FIGS. 3 and 9), and the rib portion 24 of the rear shaft 4 is formed behind the front shaft 3. The rear shaft 4 can be rotated with respect to the front shaft 3 by being fitted into the circumferential recess 26, but is fixed so as not to drop off. In addition, a rib portion (positioning rib portion) 27 for positioning the rear shaft 4 is formed every 90 degrees in the circumferential concave portion 26 formed behind the front shaft 3 (FIG. 8). Each time the rear shaft 4 is rotated 90 degrees with respect to the front shaft 3, the positioning rib portion 27 and the rib portion 24 disposed in front of the rear shaft 4 come into contact with each other, and rotation is restricted.

When the weight storage part 19 of the front shaft 3 and the fixing member storage part 22 of the rear shaft 4 are in a non-opposing relationship, that is, the position where the weight storage part 19 and the fixing member storage part 22 differ by 90 degrees. If there is a relationship, the attractive force between the magnet 21 fixed behind the weight body 14 and the fixed magnet 23 of the rear shaft 4 is weakened or cannot receive the attractive force, and the weight body 14 can move back and forth. (FIGS. 3 and 4). When the shaft cylinder 1 is swung in the vertical direction, when the weight body 14 moves forward, a forward force is applied to the receiving member 15 of the weight body 14, the chuck body 7 moves forward, the lead is extended, and the normal swing-out is performed. Can be used as a mechanical pencil.
On the other hand, when the rear shaft 4 is rotated so that the weight housing portion 19 of the front shaft 3 and the fixing member housing portion 22 of the rear shaft 4 are opposed to each other, the rear shaft 4 is fixed to the rear end portion of the weight body 14. The magnet 21 and the fixed magnet 23 in the fixed member storage portion 22 of the rear shaft 4 are attracted to fix (lock) the weight body 14 (FIG. 10). As a result, the weight body 14 does not move even if the shaft cylinder 1 is swung in the vertical direction, for example when being carried, and unintended centering can be prevented. When used again as a swing-out mechanical pencil, the rear shaft 4 may be rotated by a certain amount to release the fixation between the weight body 14 and the fixed magnet 23. In the present embodiment, the fixing of the weight body 14 and the fixed magnet 23 is released by rotating the rear shaft 4 by 90 degrees.
As described above, the weight body is fixed and released using magnetic force, so that the weight body is fixed and released without applying a load to the parts related to fixing the weight body and without causing excessive deformation. I can do it. As a result, the weight body can be fixed well over a long period of time.

In addition, when a magnetic force is used for fixing / releasing the weight body as in this embodiment, the weight body of the front shaft and the fixed magnet in the rear shaft are fixed while making a “click” sound, Since the vibration at the time of fixing is transmitted to the hand, it is possible to recognize other than visually that the weight body has been correctly fixed. In addition, the user can enjoy the sound and feel at the time of fixing that cannot be obtained by other methods of fixing the weight.
Further, when magnetic force is used as in the present embodiment, the number of parts related to fixing / releasing the weight body can be reduced, and the shaft diameter of the portion related to the fixing structure can be reduced. For this reason, the range of mechanical pencil designs can be expanded.
And the structure which fits a front axis | shaft and a rear axis | shaft like a present Example can align easily at the time of an assembly, and can improve productivity.

In this embodiment, the weight body is made of an iron member and a magnet, and the fixing member is a fixed magnet. However, at least part of either the weight body or the fixing member is made of a magnet, and the other It is sufficient that a part is made of at least a magnet or a ferromagnetic material, and the combination can be arbitrary. It is only necessary that the weight body and the fixing member can be fixed by a magnetic force.
For example, both the weight body and the fixing member may be composed only of a magnet, or only the surface where the weight body and the fixing member face each other is a magnet, and the other part may be composed of an arbitrary member. Further, the weight body may be made of a ferromagnetic material, and the fixing member may be made of a magnet, or vice versa. Only the surface where the weight body and the fixing member face each other is a ferromagnetic material or a magnet. This part may consist of arbitrary members. It is only necessary that the weight body and the fixing member can be fixed by a magnetic force.

  Further, in this embodiment, the front shaft weight storage portion and the rear shaft fixing member storage portion are formed in two rooms, and one weight and fixing member are stored in each room. The number and the number of weights and fixing members stored in the storage units can be arbitrarily determined. Depending on how much the rotation angle of the rear shaft is used to fix and release the weight and how much the magnetic force between the weight and the fixing member is to be stored, it can be stored in the front and rear shafts. What is necessary is just to determine the number of the room of a part, the number of the weight body and fixing member which are put in the storage part, and the strength of magnetic force. As in this embodiment, when the weight body and the fixing member are stored one by one in the radially opposing positions, the core is more stable than the case where the weight body / fixing member is disposed only in one of the storage portions. You can pay out.

  In addition, in this embodiment, identification display printing of fixation / release is provided on the front shaft 3 and the rear shaft 4 so that the fixation and release of the weight body can be visually recognized. More specifically, an indication meaning “fixed” is printed on the outer peripheral surface behind the front shaft 3 corresponding to the weight housing portion 19, and an indication meaning “release” is displayed on the other rear portion of the front shaft 3. To print. On the other hand, a display meaning “fixed” is also printed on the outer peripheral surface of the front side of the rear shaft 4 corresponding to the fixed member storage portion 22. In this way, the weight is fixed or released depending on whether the "fixed" display on the front shaft 3 and the "fixed" display on the rear shaft 4 are in a facing relationship or in a non-facing relationship. Can recognize the state of the body. Of course, the means for recognizing and releasing the weight body is not limited to the identification display printing on the shaft tube as in the present embodiment. As a means of identification display other than printing, a means such as providing a window hole in front of the front shaft so that the weight body cannot be seen from the window hole when the weight body is fixed to the rear shaft can be considered. .

Next, a second embodiment of the present invention will be described with reference to FIGS. The second embodiment is an example of a mechanical pencil that can fix and release a weight body by allowing a rear shaft having a fixing member (fixed magnet) to move in the front-rear direction of the front shaft. In the following, description of the same configuration as in the first embodiment is omitted.
In this embodiment, the rear shaft 4 can be moved back and forth with respect to the front shaft 3 and is disposed so as to include the front shaft 3. At this time, a groove portion 28 having a length in the longitudinal direction formed on the front shaft 3 is engaged with a rib portion 29 formed on the inner surface of the rear shaft 4 and having a width corresponding to the groove portion 28 of the front shaft 3. Therefore, the movement of the rear shaft 4 in the radial direction and the front-rear direction with respect to the front shaft 3 is restricted (FIGS. 13 and 16). Although there is no need to restrict the movement of the rear shaft 4 in the radial direction relative to the front shaft 3, it is useful when positioning between the front shaft and the rear shaft is necessary for reasons such as design.
Here, the rear shaft 4 can be positioned with respect to the front shaft 3 at two locations, front and rear. This configuration will be described in detail. On the outer peripheral surface of the front shaft 3, two recessed portions having substantially the same shape are formed at different positions in the longitudinal direction of the shaft tube (recessed portions 30 and 31). A convex portion 32 having a shape corresponding to the concave portion of the front shaft 3 is formed. By fitting the concave portions 30, 31 of the front shaft 3 and the convex portion 32 of the rear shaft 4, the rear shaft 4 can be positioned at two front and rear positions with respect to the front shaft 3. In this embodiment, the contact surfaces of the concave portions 30 and 31 of the front shaft 3 and the convex portions 32 of the rear shaft 4 in the axial tube direction are inclined surfaces 33, and the concave portions 30 and the concave portions 31 of the front shaft 3 are used. The outer diameter of the front shaft in between is made slightly small so that the rear shaft 4 can be moved back and forth with respect to the front shaft 3 easily.
Further, the internal configuration of the front shaft 3 and the rear shaft 4 will be described in detail. The front shaft 3 is formed of a cylindrical member, and a core feeding unit 5 including a weight body 14 made of an iron material is disposed therein. The weight body 14 has a cylindrical shape and includes the core feeding unit 5. On the other hand, a cylindrical fixed magnet (fixing member) 23 is arranged in front of the rear shaft 4.

In this embodiment, when the rear shaft 4 is moved rearward with respect to the front shaft 3, that is, when the convex portion 32 of the rear shaft 4 is fitted in the concave portion 30 of the front shaft 3, The fixed magnet 23 is located at a different location in the longitudinal direction of the shaft tube 1. That is, there is a space in the longitudinal direction of the shaft tube 1 between the weight body 14 and the fixed magnet 23, and the attractive force between the weight body 14 and the fixed magnet 23 is weakened or cannot receive the attractive force. The weight body 14 can be moved back and forth (FIGS. 12 and 13). Then, when the shaft cylinder 1 is swung up and down and the weight body 14 moves forward, a forward force is applied to the receiving member 15 of the weight body 14, the chuck body 7 moves forward, and the lead L is fed out. Can be used as a swing-out mechanical pencil.
On the other hand, when the rear shaft 4 is moved to the front of the barrel 1, that is, when the convex portion 32 of the rear shaft 4 is fitted in the concave portion 31 of the front shaft 3, the weight body 14 and the fixed magnet 23 Is located at a location where the longitudinal directions of the shaft cylinder 1 overlap. For this reason, the weight body 14 and the fixed magnet 23 are attracted, and the weight body 14 is fixed (FIGS. 15 and 16). As a result, the weight body 14 does not move even if the shaft cylinder 1 is swung in the vertical direction, for example when being carried, and unintended centering can be prevented.
In addition, when using again as a swing-out type mechanical pencil, the rear axis | shaft 4 should just be moved back with respect to the front axis | shaft 3, and the fixed of the said weight body 14 and the fixed magnet 23 should just be cancelled | released. As described above, when the convex portion 32 of the rear shaft 4 is fitted in the concave portion 30 of the front shaft 3, the weight body 14 is released from being fixed.
As described above, the weight body is fixed and released using magnetic force, so that the weight body is fixed and released without applying a load to the parts related to fixing the weight body and without causing excessive deformation. I can do it. As a result, the weight body can be fixed well over a long period of time.

In this embodiment, the facing area between the weight body and the fixed magnet (fixing member) can be increased, and the weight body can be more reliably fixed.
Further, in this embodiment, the visibility related to fixing and releasing the weight body is improved. This is because the external appearance of the entire mechanical pencil changes between when the weight is fixed and when it is released. In addition, the rear part of the front shaft exposed when the rear shaft is moved forward with respect to the front shaft is made a different color from others, or the identification display is described on the rear part of the front shaft. The visibility related to the fixation and release of the weight body is further improved.

  In this embodiment, the weight body is made of a ferromagnetic iron member and the fixed member is a fixed magnet. However, as in the first embodiment, the weight body is made of an iron member and a magnet and fixed. The member may be a fixed magnet. Not limited to this, any part of the weight body or the fixing member may be made of at least a magnet, and the other part may be made of at least a magnet or a ferromagnetic material. It can be. It is only necessary that the weight body and the fixing member can be fixed by a magnetic force.

Finally, a third embodiment of the present invention will be described with reference to FIGS. The third embodiment is a modification of the rear shaft of the second embodiment, and is an example of a cap-type mechanical pencil in which a weight fixing member is disposed in a cap (rear shaft). In the following description, description of the same configuration as in the second embodiment is omitted.
In this embodiment, the rear shaft 4 can be attached to and detached from the front and rear of the front shaft 3. The rear shaft 4 is a so-called cap. In this embodiment, the rear shaft 4 is provided with a clip, but this clip may or may not be provided.
A circumferential concave portion 34 is provided on the front outer peripheral surface of the front shaft 3, and a circumferential concave portion is also formed on the large-diameter collar portion of the eraser receiving member 16 of the core feeding unit 5 included in the front shaft 3. 35 is provided. On the other hand, a circumferential rib portion 36 is provided inside the rear shaft (cap) 4, and the rib portion 36 in the rear shaft (cap) 4 is the concave portion 34 of the front shaft or the concave portion of the eraser receiving member 16. By fitting in 35, the rear shaft (cap) 4 is fixed to the front shaft 3 or the eraser receiving member 16.
The internal configuration of the front shaft 3 and the rear shaft (cap) 4 will be described in detail. The internal structure of the front shaft 3 is the same as that of the second embodiment. The cylindrical weight body 14 disposed in the front shaft 3 is composed of a magnet. On the other hand, the rear shaft (cap) 4 has a cylindrical shape with one end in the longitudinal direction. Below, let the opening side of the rear axis | shaft (cap) 4 be the front, and let a bottomed side be back. A cylindrical fixed magnet (fixing member) 23 is disposed in front of the rear shaft (cap) 4. The fixed magnet 23 has a magnetic pole different in the radial direction from the weight body 14 in the front shaft 3, and the fixed magnet 23 and the weight body 14 in the front shaft 3 are positioned to face each other. It is arranged so that attractive force works when it hits.

In this embodiment, when the rear shaft (cap) 4 is fitted behind the eraser receiving member 16, that is, the front shaft 3, the weight body 14 and the fixed magnet 23 differ in the longitudinal direction of the shaft tube 1. Located in the place. That is, there is a space in the longitudinal direction of the shaft tube 1 between the weight body 14 and the fixed magnet 23, and the attractive force between the weight body 14 and the fixed magnet 23 is weakened or cannot receive the attractive force. The weight body 14 can be moved back and forth (FIGS. 17 and 18). Then, when the shaft cylinder 1 is swung up and down and the weight body 14 moves forward, a forward force is applied to the receiving member 15 of the weight body 14, the chuck body 7 moves forward, and the lead L is fed out. Can be used as a swing-out mechanical pencil.
On the other hand, when the rear shaft (cap) 4 is fitted in front of the front shaft 3, the weight body 14 and the fixed magnet 23 are located at a position where the longitudinal direction of the shaft tube 1 overlaps. For this reason, the weight body 14 and the fixed magnet 23 of the rear shaft (cap) 4 are attracted to fix the weight body 14 (FIGS. 21 and 22). As a result, the weight body 14 does not move even if the shaft cylinder 1 is swung in the vertical direction, for example when being carried, and unintended centering can be prevented.
When used again as a swing-out mechanical pencil, the rear shaft 4 is removed from the front of the front shaft 3 and fitted to the rear of the front shaft 3 (the eraser receiving member 16) to release the weight body 14 from being fixed. Just do it. Further, the rear shaft 4 may be left off from the front of the front shaft 3, and even in this case, the fixing of the weight body 14 is released.
As described above, the weight body is fixed and released using magnetic force, so that the weight body is fixed and released without applying a load to the parts related to fixing the weight body and without causing excessive deformation. I can do it. As a result, the weight body can be fixed well over a long period of time.

Even in the present embodiment, as in the second embodiment, the facing area between the weight body and the fixed magnet can be increased, and the weight body can be more reliably fixed.
Further, in this embodiment, the operations related to the release of the fixing of the weight body and the fixing of the weight body, that is, the operation related to when the mechanical pencil is used and not used (the operation of removing the cap from the front shaft, To attach to the front shaft). For this reason, the operation | movement which concerns on fixation / release of a weight body is intuitive, and the operativity becomes more excellent.

  In this embodiment, the weight is made of a magnet and the fixed member is a fixed magnet. However, as in the first embodiment, the weight is made of an iron member and a magnet, and the fixed member is a fixed magnet. good. Not limited to this, any part of the weight body or the fixing member may be made of at least a magnet, and the other part may be made of at least a magnet or a ferromagnetic material. It can be. It is only necessary that the weight body and the fixing member can be fixed by a magnetic force.

DESCRIPTION OF SYMBOLS 1 Shaft cylinder 2 Lead member 3 Front shaft 4 Rear shaft 5 Center feeding unit 6 Core tank 7 Chuck body 8 Chuck ring 9 Slide member 10 Core detent member 11 Elastic body 12 Core 13 Repelling member (chuck spring)
DESCRIPTION OF SYMBOLS 14 Weight 15 Receiving member 16 Eraser receiving member 17 Eraser 18 Knock member 19 Weight body accommodating part 20 Iron member 21 Magnet 22 Fixed member accommodating part 23 Fixed magnet (fixing member)
24 Rib part 25 Leg part 26 Circumferential concave part 27 Positioning rib part 28 Rib part 29 Rib part 30 Concave part 31 Concave part 32 Convex part 33 Inclined surface 34 Circumferential concave part 35 Cylindrical concave part 36 Circumferential rib Part L core

Claims (4)

A mechanical pencil in which a core feeding mechanism is disposed in a shaft cylinder having a front shaft and a rear shaft, and the core feeding mechanism is actuated by a weight body disposed in the front shaft, and is fixed to the rear shaft. the member is fixed, together with the forms from the weight body or any one of a part at least magnets of the stationary member, and at least without a magnet or a ferromagnetic material, said fixing member and said weight body part of the other face The weight body and the fixing member can be fixed by a magnetic force when arranged at a position, and the weight body and the fixing member are arranged when the weight body and the fixing member are arranged at a non-opposing position. A mechanical pencil characterized in that it can be released . The rear shaft is rotatable with respect to the front shaft, and the weight housing portion housing the weight body and the fixing member housing portion housing the fixing member are opposed to each other by the rotation of the rear shaft with respect to the front shaft. The mechanical pencil according to claim 1, wherein the mechanical pencil can be switched to a non-facing position . The rear shaft can be moved back and forth with respect to the front shaft, and the weight and the fixing member can be switched between a facing position and a non-facing position by moving the rear shaft back and forth with respect to the front shaft. The mechanical pencil according to claim 1. A mechanical pencil having a front shaft and a cap for the front shaft, a core feeding mechanism disposed in the front shaft, and the core feeding mechanism being operated by a weight disposed in the front shaft, A fixing member is fixed to the cap, and at least a part of either the weight body or the fixing member is made of a magnet, and the other part is made of at least a magnet or a ferromagnetic body. When the weight and the fixing member can be switched between a facing position and a non-facing position by allowing the weight and the fixing member to be attached to and detached from the front and rear, the weight body and the fixing member are disposed at the facing positions. The weight body and the fixing member can be fixed by a magnetic force, and the weight body and the fixing member can be released when the weight body and the fixing member are arranged at non-opposing positions. Features Mechanical pencil.

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