JP7129921B2 - mechanical pencil - Google Patents

Description

The present invention relates to mechanical pencils.

Conventionally, a lead tank is built inside the barrel, a chuck is provided in front of the lead tank and interlocked with the lead tank, the lead is accommodated in the lead tank, and the rear end of the mechanical pencil is pressed to open the front end of the barrel. A mechanical pencil that writes on paper with the lead protruding from the part is well known. to be replenished.

In such a mechanical pencil, if the inner diameter of the lead tank is large, it is difficult to smoothly supply the lead to the chuck.
On the other hand, if the inner diameter of the lead tank is small, only a small amount of lead can be accommodated in the lead tank, and it is necessary to frequently replenish the lead in the lead tank. Since it is not possible to check the lead consumption status from the outside, it is troublesome to carry around a mechanical pencil without a spare lead in the lead tank, or to unexpectedly break the lead during use. I was afraid.

In view of these problems, in Patent Document 1 (Japanese Utility Model Publication No. 61-78685), a lead tank containing a lead is made transparent, and a part of the lead tank is visible from the outside through a window provided in the barrel. A pencil is disclosed.
In Patent Document 1, the wick in the wick tank is visually confirmed directly through the window, but since the wick generally has a small diameter and is black in color, it is difficult to see whether or not the wick is present. I was afraid.

Japanese Utility Model Publication No. 61-78685

The present invention has been devised in consideration of such conventional problems. An object of the present invention is to obtain a mechanical pencil that allows easy confirmation of the situation from the outside.

The present invention
"1. A shaft cylinder having a front end opening from which a lead protrudes and a rear end opening for replenishing the lead, a lead tank built in the shaft cylinder, and the lead positioned in front of the lead tank. a chuck interlocking with the tank, a chuck spring for urging the chuck and the wick tank rearward, an accessory, an accessory holding member positioned behind the wick tank and holding the accessory, and the accessory and an operating portion positioned behind the holding member and protruding from the rear end opening of the shaft cylinder. By operating the operating portion, the chuck interlocked with the operating portion advances to feed out the lead. In the mechanical pencil, a display body is disposed in the shaft cylinder so as to be in contact with the rear end of the lead accommodated in the lead tank so as to be movable back and forth in the axial direction of the mechanical pencil. As the last core moves forward, the display body in contact with the rear end of the spare core follows and moves forward, and the movement state of the display body is displayed on the shaft cylinder to the outside of the shaft cylinder. a lead abutting portion which abuts on the rear end of the lead which is inserted into and removed from the lead tank and accommodated in the lead tank, and the lead abutting portion; When the width of the display portion is X and the width of the core contact portion is Y when the window is viewed from the front with the axial direction of the mechanical pencil up and down (2) a mechanical pencil characterized in that X and Y satisfy a relational expression of X>Y;
2. The display body is loosely attached to the accessory holding member, and in a state in which the accessory holding member is attached to the barrel or the core tank, the display is positioned in the barrel and moves back and forth in the axial direction. 2. The mechanical pencil according to item 1, wherein the display body can be removed from the barrel by detaching the accessory holding member from the barrel or the lead tank.
3. 3. The mechanical pencil according to item 1 or 2, wherein the window is formed by forming a transparent or translucent part of the barrel.
4. 4. The mechanical pencil according to any one of items 1 to 3, wherein the display body is biased toward the tip opening of the barrel by an elastic member.
5. 5. The mechanical pencil according to any one of items 1 to 4, wherein the spare lead can be retracted rearward from a state in which the lead contact portion of the display is in contact with the rear end of the spare lead. .
6. 6. The mechanical pencil according to any one of items 1 to 5, wherein the front end of the lead contact portion is positioned inside the lead tank when the display body is in the most retracted state. ”.

In the present invention, in a mechanical pencil that advances a chuck interlocked with the operation part by operating the operation part protruding from the rear end opening of the barrel to feed the lead, the presence or absence of the remaining lead in the lead tank and the consumption status can be easily confirmed from the outside.

FIG. 4 is a vertical cross-sectional view showing a state in which the mechanical pencil of the present embodiment has a spare lead in the lead tank. 2 is an A1-A1 cross-sectional view of the mechanical pencil of FIG. 1; FIG. FIG. 2 is a vertical cross-sectional view of the mechanical pencil of FIG. 1 showing a state in which there is no spare lead in the lead tank; 4 is a cross-sectional view of the mechanical pencil of FIG. 3 taken along line A3-A3; FIG. 4 is a cross-sectional view of the mechanical pencil of FIG. 3 taken along line B3-B3; FIG. FIG. 2 is a vertical cross-sectional view showing a state in which a lead is replenished in the mechanical pencil of FIG. 1; FIG. 2 is a longitudinal sectional view showing a state in which the eraser of the mechanical pencil of FIG. 1 is used; It is a longitudinal cross-sectional view showing a modification of the mechanical pencil. FIG. 11 is a partial vertical cross-sectional view showing another modification of the mechanical pencil; 9B is a partial longitudinal sectional view showing the operation of the mechanical pencil of FIG. 9A; FIG. 9B is a partial longitudinal sectional view showing the operation of the mechanical pencil of FIG. 9A; FIG. FIG. 10 is a partial vertical cross-sectional view showing still another modification of the mechanical pencil; 10B is a partial vertical cross-sectional view showing the operation of the mechanical pencil of FIG. 10A; FIG. 10B is a partial vertical cross-sectional view showing the operation of the mechanical pencil of FIG. 10A; FIG. FIG. 10 is a partial vertical cross-sectional view showing still another modification of the mechanical pencil; 11B is a partial longitudinal sectional view showing the operation of the mechanical pencil of FIG. 11A; FIG. 11B is a partial longitudinal sectional view showing the operation of the mechanical pencil of FIG. 11A; FIG. FIG. 10 is a longitudinal sectional view showing still another modification of the mechanical pencil; FIG. 10 is a longitudinal sectional view showing still another modification of the mechanical pencil; FIG. 10 is a vertical cross-sectional view showing a modified example of the rear barrel of the mechanical pencil; 14B is a CC cross-sectional view of the rear shaft of FIG. 14A; FIG. FIG. 10 is a longitudinal sectional view showing still another modification of the mechanical pencil; 15B is a longitudinal sectional view showing the operation of the mechanical pencil of FIG. 15A; FIG.

The mechanical pencil 1 of this embodiment will be described in detail below with reference to the drawings.

FIG. 1 is a vertical cross-sectional view showing a mechanical pencil 1 of this embodiment with a spare lead 91 in a lead tank 8, and FIG. 3 is a longitudinal sectional view showing the mechanical pencil 1 of FIG. 1 without a spare lead 91 in the lead tank 8, and FIG. 4 is a cross section A3-A3 of the mechanical pencil 1 of FIG. 5 is a cross-sectional view of the mechanical pencil 1 of FIG. 3 taken along the line B3-B3.
In this specification, the direction in which the central axis of the mechanical pencil 1 extends (longitudinal direction, vertical direction in a vertical cross-sectional view) is the axial direction, and the direction perpendicular to the axial direction is the radial direction (diameter direction). The circumferential direction of is defined as the circumferential direction. In addition, along the axial direction, the side closer to the surface to be written, such as a paper surface, is defined as the front side, and the side away from the surface to be written is defined as the rear side. That is, the upper side in the vertical cross-sectional view, that is, the side of the cap 5 is expressed as the rear side, and the lower side in the vertical cross-sectional view, that is, the side of the front end opening 3a of the shaft cylinder is expressed as the front side.

As shown in FIG. 1, the mechanical pencil 1 of this embodiment has a tip 3 at the front of a cylindrical barrel main body 2, and a rear barrel 4 at the rear of the barrel main body 2. 2, the tip 3, and the rear barrel 4 form a barrel, and a substantially cylindrical cap 5 with a closed rear end projects from a rear end opening 4a.
A substantially cylindrical accessory holding member 6 is inserted forward from the rear end opening 4a into the barrel main body 2, and the front end of the accessory holding member 6 is reduced in diameter to form a fitting portion 6a. , is inserted into a fitting portion 8a provided at the rear end of the lead tank 8, which will be described later.
As shown in FIG. 2, a plurality of engagement grooves 2a are formed on the rear inner peripheral surface of the barrel main body 2, and a plurality of engagement projections 6b are formed on the outer peripheral surface of the attachment holding member 6 to engage. The engagement between the groove 2a and the engaging projection 6b prevents rotation (restriction of rotation) between the barrel main body 2 and the accessory holding member 6. As shown in FIG.
As shown in FIG. 1, the rear end of the accessory holding member 6 is hollowed out in a cylindrical shape, and a cylindrical eraser 7 is inserted as an accessory. The eraser 7 is covered with the cap 5 which is detachably screwed with the cap 5 having a female screw portion 5a on the front inner peripheral surface.

A wick tank 8 made of a polypropylene pipe and having an inner diameter of 2.2 mm is arranged inside the barrel body 2 . is provided with a fitting portion 8a, and the fitting portion 6a provided at the front end of the accessory holding member 6 is inserted, and the front end of the wick tank 8 is inserted into a substantially cylindrical connector 10, A chuck 11 made of brass is press-fitted and fixed to the tip opening of the lead tank 8 .

The front portion of the chuck 11 is divided into a plurality of sections, and a ring-shaped fastener 12 is fitted onto the chuck head portion 11a. A chuck spring 13 is tightly fitted, and the chuck head 11a biased backward by the chuck spring 13 holds the core 9. As shown in FIG.
The tip 3 has a tapered shape with both ends opened, the lead 9 protrudes from the tip opening 3a, a lead holder 14 for holding the lead 9 is arranged inside, and a female screw part 3b is provided on the rear inner peripheral surface. and is screwed with a male screw portion 10a provided on the outer peripheral surface of the front portion of the connector 10. As shown in FIG.

The interior of the accessory holding member 6 is hollowed out in a cylindrical shape from the front end to a depth of about 3/4 of the total length, and slits 6d extending in the axial direction are formed on both side surfaces.
A substantially cylindrical display body 15 is arranged in the interior of the accessory holding member 6 so as to be movable back and forth. A spring 16 is tightly fitted between the accessory holding member 6 and the display body 15. Protrusions 15a are formed on both sides of the rear portion of the display body 15, the protrusions 15a are fitted into the slits 6d, and display portions 15b are provided on the sides of the protrusions 15a. there is
The front portion of the display body 15 is provided with a core contacting portion 15c whose diameter is reduced from the front end to about 1/2 of the total length, and the front end of the core contacting portion 15c is inserted into the lead tank 8. .
The barrel main body 2 is molded from a transparent resin, and the surface of the barrel main body 2 other than the window 2b is printed with a color to form the window 2b.
(In FIGS. 1, 2, 3, and 4, the portion indicated by the dashed line is the window portion 2b.)
As shown in FIGS. 2, 4, and 5, when the window 2b is viewed from the front, the width X of the display portion 15b of the display body 15 is 3 mm, and the width Y of the core contact portion 15c of the display body 15 is 3 mm. is 2 mm, and the width X1 of the window 2b is 3 mm.
Although not shown, the height of the window is 5 mm.
As shown in FIG. 1, when there is a spare lead 91 in the lead tank 8, the front end of the lead abutment portion 15c contacts the rear end of the spare lead 91 accommodated in the lead tank 8, thereby displaying Since the display portion 15b of the body 15 is located behind the window portion 2b of the barrel main body 2, the display portion 15b is not visible through the window portion 2b of the barrel main body 2.

It is preferable that the color of the display portion 15b and the color of the portion forming the periphery of the window portion 2b are different from each other. For example, when the display portion 15b has a dark color, it is preferable that the portion forming the periphery of the window portion 2b has a light color. In particular, when the display portion 15b has a dark color and the portion forming the periphery of the window portion 2b has a color close to white, the display portion 15b is visually recognized against the periphery of the window portion 2b. easier and preferred.

When the lead 9 is worn out due to writing, if the cap 5 is pushed forward against the elastic force of the chuck spring 13, the accessory holding member 6 screwed with the cap 5 will be pushed forward. The lead tank 8 fitted with the accessory holding member 6 moves forward, the chuck 11 moves forward while gripping the lead 9, and the fastener 12 contacts the inner surface of the tip 3 and moves. is stopped, and the core 9 is fed out until the fastener 12 comes off the chuck head 11a and the chuck head 11a expands.
Even if the chuck head 11a expands, the lead 9 is held by the lead holder 14 and will not drop from the tip opening 3a.
When the pressing of the cap 5 is stopped, the resilience of the chuck spring 13 causes the lead tank 8 to move rearward, the chuck 11 to move rearward, and the fastener 12 to come into contact with the front end of the connector 10 to stop and stop the chuck head. When the chuck head 11a is closed and the lead 9 is fixed, writing becomes possible.

Next, with reference to FIGS. 3, 4, and 5, a state in which the mechanical pencil 1 of the present embodiment does not have the spare lead 91 will be described in detail.
The lead 9 held by the chuck head 11a is used up by writing, and the last spare lead 91 stored in the lead tank 8 drops into the chuck 11 due to its own weight and contacts the rear end of the spare lead 91. As the display body 15 follows and moves forward, the display portion 15b of the display body 15 is visible through the window portion 2b of the barrel main body 2. As shown in FIG.
At this time, since the inner diameter of the lead tank 8 is small, lead supply to the chuck 11 is smooth.
Also, even if the mechanical pencil 1 is held with the tip opening 3a facing upward, the display body 15 is biased forward by the spring 16 and does not move backward, and the window 2b displays the lead tank 8. The display of the state in which there is no spare lead 91 inside is maintained. Note that the spring 16 can be omitted. In this case, the display body 15 advances by its own weight when the front end opening 3a is directed downward without the spare core 91. As shown in FIG. On the other hand, when the tip opening 3a is directed upward, the display body 15 retreats due to its own weight. Even in this case, the presence or absence of the spare lead 91 can be confirmed with the tip opening 3a facing downward.

Next, referring to FIG. 6, the state of replenishing the lead 9 to the mechanical pencil 1 of this embodiment will be described in detail.
When the barrel main body 2 is gripped with one hand and the cap 5 is gripped with the other hand and the cap 5 is pulled backward, the cap 5 engages the attachment holding member 6 with the female screw portion 5a on the front inner peripheral surface thereof. Since it is screwed into the male screw portion 6c on the outer peripheral surface of the rear portion of the cap 5, it does not detach from the accessory holding member 6 even if a force in the axial direction is applied. The fitting portion 6a at the front end of the accessory holding member 6 and the fitting portion 8a at the rear end of the lead tank 8 are disengaged, and the cap 5 and the accessory holding member 6 in which the eraser 7 is inserted are connected. It is pulled out from the mechanical pencil 1 in this state, and the rear end opening 4a is opened.
At this time, the display body 15 moves forward due to its own weight and the elastic force of the spring 16, but the projections 15a provided on both sides of the rear portion of the display body 15 move toward the slits provided on both sides of the accessory holding member. 6d, the projecting portion 15a abuts the front end of the slit 6d, preventing the display 15 from falling from the accessory holding member 6, and the display 15 is also removed from the mechanical pencil 1.
When the lead 9 is dropped into the mechanical pencil 1 from the rear end opening 4a, the lead 9 is accommodated in the lead tank 8. - 特許庁
By holding the barrel main body 2 with one hand and the cap 5 with the other hand, the accessory holding member 6 and display body 15, which are still connected to the cap 5, are removed from the rear end opening 4a of the mechanical pencil 1. When the lead 9 is inserted into the lead tank 8, the fitting portion 6a formed at the front end of the accessory holding member 6 is inserted into the fitting portion 8a provided at the rear end of the lead tank 8, and the lead 9 is inserted into the lead tank 8. Replenishment is completed.

Next, the state of using the eraser 7 of the mechanical pencil 1 of the present embodiment will be described in detail with reference to FIGS. 2 and 7. FIG.
When the barrel main body 2 is gripped with one hand and the cap 5 is gripped with the other hand and the cap 5 is rotated counterclockwise as viewed from the rear, the attachment holding member 6 to which the cap 5 is screwed is also rotated. Although a counterclockwise force is applied when viewed from the rear, the accessory holding member 6 has a plurality of engaging projections 6b formed on its outer peripheral surface and a plurality of engaging grooves formed on the rear inner peripheral surface of the barrel main body 2. 2a, it does not rotate with respect to the barrel body 2 even if a force is applied in the circumferential direction. and the female screw portion 5a provided on the inner peripheral surface of the cap 5 are unscrewed, and the eraser 7 inserted into the accessory holding member 6 is exposed and ready for use.

In the present embodiment, the width of the display portion 15b can be increased without increasing the inner diameter of the lead tank 8, and the moving state of the display body 15 can be visually recognized from the window portion 2b, thereby allowing the movement of the display body 15 to be accommodated in the lead tank 8. The presence or absence of the spare lead 91 and the consumed state can be easily confirmed from the window 2b, and the lead supply to the chuck 11 is smooth.
In addition, the cap 5, the eraser 7, the accessory holding member 6, and the display body 15 are all removed from the mechanical pencil 1 simply by pulling the cap 5 toward the rear in the axial direction with respect to the mechanical pencil 1. The end opening 4a can be opened, and the double trouble of first removing the cap 5 from the mechanical pencil 1 and placing it on the desk and then removing the accessory holding member 6 with the eraser 7 inserted and placing it on the desk. Therefore, the lead 9 can be easily replenished without losing the accessory holding member 6 holding the cap 5 or the eraser 7 or the display body 15. - 特許庁
Further, the eraser 7 can be exposed only by rotating the cap 5 in the circumferential direction with respect to the mechanical pencil 1, and the portion of the mechanical pencil 1 to be gripped when the eraser 7 is used and when the lead 9 is replenished. never changed.

In this embodiment, a display member 15 is arranged in the shaft cylinder so as to be in contact with the rear end of the lead 9 accommodated in the lead tank 8 so as to be movable back and forth in the axial direction. 9 moves forward, the display body 15 in contact with the rear end of the spare core 91 follows and moves forward, and the moving state of the display body 15 can be visually recognized from the outside of the barrel. A window portion 2b is provided, and a lead abutment portion 15c that abuts on the rear end of the lead 9 inserted into and removed from the lead tank 8 and accommodated in the lead tank 8, and a lead contact portion 15c behind the lead abutment portion 15c. When the width of the display portion 15b when the window portion 2b is viewed from the front is X, and the width of the core contact portion 15c is Y, X and Y are such that X>Y When the last lead 9 in the lead tank 8 enters the chuck 11, the display body 15 moves forward following the lead 9, and the display body 15 moves forward from the window portion 2b. Since the moving state of the lead 15 can be seen and the width of the display portion 15b can be widened without enlarging the inner diameter of the lead tank 8, lead supply to the chuck 11 is smooth, and the spare leads in the lead tank 8 can be smoothly fed. It is possible to obtain a mechanical pencil 1 in which the presence or absence of the lead 91 and the state of consumption of the lead 9 can be easily confirmed from the outside.

When there are a plurality of leads 9 including a spare lead 91 in the lead tank 8, the front end of the spare lead 91 comes into contact with the rear end of the chuck 11 due to its own weight, and the front end of the lead contact portion 15c of the display body 15 contacts. The display body 15 does not move forward by contacting the rear end of the spare core 91 due to its own weight.
On the other hand, when the lead 9 held by the chuck is used up and the spare lead 91 in the lead tank 8 becomes the last lead 9, when the last lead 9 enters the chuck due to its own weight, the spare lead 91 is lost. As the rear end moves forward, the display body 15 in contact with the rear end of the last core 9 follows the core 9 and moves forward due to its own weight.
Since the moving state of the display member 15 can be seen from the outside, the presence or absence of the spare lead 91 in the lead tank 8 and the consumption status can be easily confirmed.

The material of the display body 15 in the present embodiment is not particularly limited, and various materials such as resin and metal can be selected. You can choose the shape.
For example, when a plurality of leads 9 including a spare lead 91 are accommodated in the lead tank 8, the display body 15 abuts on the rear end of the spare lead 91, and in this state the display part 15b visible through the window part 2b. is white, and when the last lead 9 in the lead tank 8 moves forward, the display body 15 in contact with the rear end of the last lead 9 follows the lead 9 and moves forward. By making the display portion 15b visible through the window portion 2b red, the presence or absence of the spare lead 91 in the lead tank 8 can be easily confirmed from the outside by the color change of the window portion 2b from white to red, which is preferable.
In addition, by printing characters or imprinting symbols on the display portion 15b of the display body 15, the presence or absence of the spare lead 91 in the lead tank 8 can be easily confirmed from the outside by changing the pattern of the window portion 2b. can also
When a plurality of leads 9 including a spare lead 91 are accommodated in the lead tank 8, the display body 15 abuts on the rear end of the spare lead 91, and in this state, the display part 15b extends from the window part 2b. is not visible, and as the last lead 9 in the lead tank 8 moves forward, the display body 15 in contact with the rear end of the last lead 9 follows the lead 9 and moves forward. By making the display portion 15b visible through the window portion 2b, the presence or absence of the spare lead 91 in the lead tank 8 can be easily confirmed from the outside by making the display portion 15b visible through the window portion 2b. Or vice versa, when a plurality of leads 9 including a spare lead 91 are accommodated in the lead tank 8, the display part 15b can be seen through the window part 2b, and the display body 15 moves forward. By making the display portion 15b invisible through the window portion 2b, the presence or absence of the spare lead 91 in the lead tank 8 can be easily confirmed from the outside by making the display portion 15b invisible through the window portion 2b.
Further, in a state in which a plurality of leads 9 including a spare lead 91 are accommodated in the lead tank 8, the last lead 9 in the lead tank 8 moves forward beyond the width of the display portion 15b that can be seen through the window portion 2b. By increasing the width of the display portion 15b visible through the window portion 2b in a state in which the display body 15 moves forward following the core 9, or vice versa, the display portion visible through the window portion 2b is increased. By changing the width of the lead 15b, the presence or absence of the spare lead 91 in the lead tank 8 can be easily confirmed from the outside.
Furthermore, depending on the presence or absence of the spare lead 91 in the lead tank 8, the shape of the display portion 15b that can be seen through the window portion 2b may be changed.
Furthermore, the front end of the display body 15 is configured so as to abut not only the rear end of the spare lead 91 housed in the lead tank 8 but also the rear end of the lead 9 in the chuck 11. Since the display body 15 continuously moves forward as the core 9 wears, for example, the surface of the display section 15b is given a gradation in which the color tone and color density change continuously from the front to the rear. Alternatively, the remaining amount of the lead 9 in use may be continuously checked by changes in the color tone and color depth of the surface of the display portion 15b seen through the window portion 2b.
The width of the display portion 15b is the width of the display portion 15b in a direction (diameter direction) perpendicular to the axial direction of the mechanical pencil 1 when the window portion 2b is viewed from the front with the axial direction of the mechanical pencil 1 up and down. It indicates the length, and if the display portion 15b is columnar or cylindrical, it indicates the diameter.

In this embodiment, it is not necessary to increase the inner diameter of the core tank 8 even if the width of the display portion 15b is widened. A weight body is arranged in the gap so as to be movable back and forth in the axial direction of the mechanical pencil 1, and the chuck 11 is advanced by the weight body advanced by swinging the barrel back and forth, and the lead 9 is moved in the barrel. A retractable mechanical pencil equipped with a core retracting mechanism capable of retracting from the tip opening can be provided.
In addition, since it is not necessary to thicken the barrel of the part that is gripped by the hand when writing, even users with small hands can easily write.
The width X of the display portion 15b is preferably 2 mm or more and 5 mm or less from the viewpoint of ease of viewing and easiness of arrangement in the barrel. Since it is inserted into and removed from the wick tank 8 having a small inner diameter, it is preferably 1 mm or more and 4 mm or less, and the difference between X and Y is preferably 1 mm or more.
From the viewpoint of the moving state of the display 15 and the visibility of the display portion 15b, the width X1 of the window portion 2b is preferably 2 mm or more, and the length of the window portion 2b is preferably 3 mm or more.

The method of arranging the display body 15 in this embodiment is not particularly limited as long as it is arranged so as to be movable back and forth in the axial direction of the mechanical pencil 1. can be done.
For example, as the attachment holding member 6, an eraser holding member having an eraser 7 inserted into its rear end is used, and the display body 15 is loosely attached to the front of the eraser holding member, and the eraser holding member is attached to the rear end of the lead tank 8. is inserted, the display body 15 is positioned in the lead tank 8 and is movable back and forth in the axial direction. 15 moves forward so that the presence or absence of the remaining lead can be easily checked through the window 2b. Since the eraser holding member and the display body 15 can be removed together from the mechanical pencil 1 by a single action of pulling backward in the central direction, the cap 5 and the eraser holding member are first removed from the mechanical pencil main body, Then, it is possible to reduce the trouble of taking out the display body 15 from the lead tank 8 when replenishing the lead.
Also, when the cap 5 covering the eraser 7 is attached to the eraser holding member, the mounting/dismounting direction of the eraser holding member to/from the barrel or core tank 8 and the mounting/dismounting direction of the cap 5 to/from the eraser holding member. and are arranged in different directions, it is possible to further reduce the labor involved in replenishing the lead.
For example, the attachment/detachment of the eraser holding member to/from the lead tank 8 is performed by pushing forward/pulling backward in the axial direction of the mechanical pencil 1, and the cap 5 is attached/detached to/from the eraser holding member. by rotating the mechanical pencil 1 clockwise or counterclockwise in the circumferential direction, the barrel is gripped with one hand, the cap 5 is gripped with the other hand, and the cap 5 is rotated in the axial direction. The cap 5, the eraser 7, the eraser holding member and the display body 15 can be attached and detached from the mechanical pencil 1 all at once by pulling backward, and the lead 9 can be replenished. The cap 5 can be detached from the eraser holding member and the eraser 7 can be exposed and used by a single operation of holding, holding the cap 5 with the other hand, and rotating the cap 5 in the circumferential direction. The part to be gripped of the mechanical pencil 1 is not changed between when the lead 9 is replenished and when the eraser 7 is used.

The window portion 2b in the present embodiment is sufficient as long as the inside of the shaft tube can be visually recognized from the outside.
The window portion 2b may be provided by opening a hole communicating between the inside and outside of the barrel, or the window portion 2b may be provided by forming a part of the barrel transparent or translucent.
In particular, when a window portion 2b is provided by forming a part of the barrel transparent or semi-transparent, dust and dirt may enter the interior of the barrel and the core tank 8 from the outside, causing the display 15 to move back and forth. This is more preferable because it does not hinder the viewing of the display section 15b, or makes it difficult to see the display section 15b due to stains, scratches, or the like.
Alternatively, the window portion 2b may be provided by forming the barrel from a transparent or translucent material and applying colored printing or painting to the surface of the barrel other than the window portion 2b. The window portion 2b may be provided by attaching a colored film to the surface.
Alternatively, the entire shaft cylinder may be made of an opaque material, a portion corresponding to the window portion 2b may be opened, and a transparent body may be fitted to provide the window portion 2b. The window portion 2b may be provided by molding the entire shaft tube opaquely and molding the window portion 2b transparently.
Further, by using the window portion 2b as a lens, it is possible to make it easier to see the moving state of the display body 15 depending on the presence or absence of the spare lead 91 in the lead tank 8. FIG.

The structure in which the display body 15 of the present embodiment is brought into contact with the rear end of the lead 9 housed in the lead tank 8 and arranged so as to be movable back and forth in the axial direction of the mechanical pencil 1 is not particularly limited. It is preferable to arrange a coil spring (spring 16) inside the cylinder, fix one end of the coil spring to the accessory holding member 6, and fix the other end to the display body 15 to urge the display body 15 forward.
If there is a coil spring, even if the mechanical pencil 1 without the spare lead 91 in the lead tank 8 is held with the tip opening of the barrel facing upward, the display body 15 will be held by the coil spring. Since the display body 15 is urged forward, the display body 15 does not move backward due to its own weight. This is because the display of the empty state is maintained, and the presence or absence of the spare lead 91 in the lead tank 8 and the consumption state of the lead 9 can be easily confirmed from the outside.

The material of the wick tank 8 of the present embodiment is not particularly limited, and various materials such as resin and metal can be selected, but the inner wall surface thereof is preferably treated with silicone.
By applying the silicone treatment, even when the display body 15 comes into contact with the inner wall surface of the lead tank 8, the display body 15 is not prevented from moving smoothly back and forth.
Further, the rear end of the spare lead 91 rubs against the inner wall surface of the lead tank 8, so that the inner wall surface of the lead tank 8 is less likely to become dirty. As a result, the inner wall surface of the lead tank 8 is less likely to get dirty.

The shape of the wick tank 8 of the present embodiment is not particularly limited, and various shapes such as a cylindrical shape can be selected. .
By providing the enlarged-diameter portion, the front end of the enlarged-diameter portion serves as a lead support portion, and in a state in which a plurality of leads including the spare lead 91 are accommodated in the lead tank 8, the rear end portion of the spare lead 91 is positioned on the enlarged-diameter portion. It can be spaced apart from the inner wall surface.
In addition, by providing the enlarged diameter portion, when the lead 9 is replenished from the rear end opening of the barrel, the lead tank 8 can be replenished with the lead 9 as compared with the case where the lead tank 8's rear end serves as the entrance of the lead 9 as it is. Replenishment of the wick 9 is facilitated.
Also, when the mechanical pencil 1 is carried around with the spare lead 91 stored in the lead tank 8 and is subject to vibration, or when the mechanical pencil 1 is subjected to an impact such as being dropped, the rear end of the spare lead 91 will not move. The inner wall surface of the lead tank 8 is less likely to become dirty due to rubbing against the inner wall surface of the lead tank 8, and the moving state of the rear end portion of the lead 9 and/or the display body 15 can be confirmed through the lead tank 8 and the window portion 2b. becomes easier.
In addition, since the powder of the lead 9 generated when the rear end portion of the spare lead 91 rubs against the inner wall surface of the lead tank 8 is reduced, the inner wall surface of the lead tank 8 is less likely to be soiled due to the powder of the lead 9 adhering to it. , the moving state of the rear end of the lead 9 and/or the display body 15 can be easily confirmed through the lead tank 8 and the window 2b.
Furthermore, clogging of the core due to the powder of the core 9 entering into the chuck 11 or the like is less likely to occur.
In addition, when the spare lead 91 is stored in the lead tank 8, the length from the rear end of the spare lead 91 to the lead support part at the front end of the enlarged diameter part is L, and the horizontal plane passing through the lead support part and the spare lead 91 are aligned. If the lead tank 8 and the expanded diameter portion are formed so that the difference between the inner diameter of the lead tank 8 and the inner diameter of the expanded diameter portion is 2Lcos θ or more, where θ is the angle to be formed, a preliminary lead is formed in the lead tank 8 . Even when the core 91 is tilted, the rear end of the spare core 91 can always be kept away from the inner wall surface of the enlarged diameter portion, so that contact between the rear end of the core 9 and the core tank 8 can be effectively suppressed. .

As accessories in the present embodiment, in addition to the eraser 7 for correcting typographical errors, a ballpoint pen, a marking pen, correction tape, a touch pen for smartphones and tablet terminals, and the like can be used as appropriate.
As the core 9, a solid core containing a reversible thermochromic microcapsule pigment and capable of forming a reversible thermochromic handwriting by writing is used, and as an attachment, the color of the handwriting by the solid core is changed by the heat of friction with the paper surface. A friction member that can change color or be decolored can also be used.

Various modifications can be made to the above-described embodiment. Modifications will be described below with appropriate reference to the drawings. In the following description and the drawings used in the following description, the same reference numerals as those used for the corresponding portions in the above-described embodiment are used for the portions that can be configured in the same manner as in the above-described embodiment, Duplicate explanations are omitted.

FIG. 8 is a longitudinal sectional view showing a modified example of the mechanical pencil 1. As shown in FIG. In the illustrated mechanical pencil 1, the barrel comprises a front barrel 21 arranged between the barrel body 2 and the tip 3, and a barrel arranged inside the front barrel 21, the barrel body 2 and the rear barrel 4. and an inner shaft 22 . The front shaft 21 has a substantially cylindrical shape as a whole. A male screw portion 21a is provided on the front outer side of the front shaft 21, and a female screw portion 21b is provided on the rear inner side of the front shaft 21. As shown in FIG. The front shaft 21 is attached to the tip 3 by screwing the male threaded portion 21 a of the front shaft 21 into the female threaded portion 3 b of the tip 3 . The inner shaft 22 has a substantially cylindrical shape as a whole. A male screw portion 22a is provided on the front outer side of the inner shaft 22, and an engaging projection 22b is provided on the rear outer side of the inner shaft 22. As shown in FIG. The inner shaft 22 is attached to the front shaft 21 by screwing the male threaded portion 22 a of the inner shaft 22 into the female threaded portion 21 b of the front shaft 21 . In addition, the inner shaft 22 is attached to the rear shaft 4 by engaging the engagement projection 22b of the inner shaft 22 with the engagement hole 4b provided in the rear shaft 4 .

The inner shaft 22 has a window portion 22c. The window portion 22c is a portion that allows the user to view the display portion 15b of the display body 15 through the window portion 22c. In this modified example, the window portion 22c is configured as a through hole penetrating the inner shaft 22 from the inner surface to the outer surface. It may be configured by inserting another transparent member into the through hole provided in the shaft 22 . At least a portion of the barrel main body 2 positioned radially outward of the window portion 22c is made of a transparent member. Thereby, the user can visually recognize the window portion 22c of the inner shaft 22 through the transparent member. The term “transparent” as used herein includes not only colorless transparency but also colored transparency.

In the mechanical pencil 1 according to this modified example, the window portion 22c can be configured by a through hole, so the visibility of the display body 15 through the window portion 22c can be improved. Furthermore, since the window portion 22c is covered with the barrel main body 2, foreign matter such as dust can be prevented from entering the inside through the window portion 22c.

Further, in the mechanical pencil 1 according to this modified example, the outer surface of the inner barrel 22 can be decorated to provide a decorative portion. In this case, since the decorated portion of the inner shaft 22 is covered with the barrel body 2, the decorated portion will not be rubbed by the user's hand or an external member, and the decorated portion will wear out. loss can be prevented.

9A to 9C are longitudinal sectional views showing other modifications of the mechanical pencil 1. FIG. In FIGS. 9A to 9C, the dashed line indicates the axial position of the tip of the core contact portion 15c in FIG. 9A.

When there is a spare lead 91 in the lead tank 8, the leading end of the lead contact portion 15c of the display body 15 is in contact with the rear end of the spare lead 91 as shown in FIG. 9A. When the core 9 is consumed and the remaining length of the core 9 decreases, the front end of the core 9 protrudes forward from the tip opening 3 a of the tip opening 3 , and the rear end of the core 9 is positioned further than the rear end of the chuck 11 . It will be positioned forward. At this time, the front end of the spare core 91 may enter the chuck 11 as shown in FIG. 9B. In this case, the core 9 and the spare core 91 are aligned along the axial direction. At this time, the display body 15 is positioned forward of the position shown in FIG. 9A by the amount of the advance of the spare core 91 .

In this state, when the core 9 is retracted to store it, the spare core 91 is also retracted by being pushed by the core 9. - 特許庁In this modification, as shown in FIG. 9C, the display body 15 can be retracted rearward from the position where the core contact portion 15c contacts the rear end of the preliminary core 91 (the position shown in FIG. 9A). It is configured. Therefore, when the spare core 91 is pushed back by the core 9 , the display body 15 can also be retracted together with the spare core 91 . As a result, the spare lead 91 can be retracted rearward from the state in which the lead contact portion 15 c of the display body 15 is in contact with the rear end of the spare lead 91 . Preferably, the display body 15 is configured to be retractable rearward by 0.5 mm or more from the position where the lead contact portion 15c abuts the rear end of the spare lead 91 . More preferably, the display body 15 is configured to be retractable rearward by 2 mm or more from the position where the core contact portion 15c contacts the rear end of the spare core 91 . The position where the lead contact portion 15c contacts the rear end of the spare lead 91 means that the front end of the spare lead 91 is not positioned behind the lead 9 along the axial direction. With the front end of the lead 91 positioned radially outside the rear end of the lead 9, the lead contact part 15c is positioned at the frontmost position, whereby the lead contact part 15c contacts the rear end of the spare lead 91. point to the location.

10A to 10C are longitudinal sectional views showing still another modification of the mechanical pencil 1. FIG. In FIGS. 10A to 10C, dashed lines indicate the axial position of the tip of the core contact portion 15c in FIG. 10A.

In the example shown in FIGS. 10A to 10C, a relief portion 15d is formed at the tip of the core contact portion 15c of the display body 15. As shown in FIG. In the illustrated example, the relief portion 15d is formed of a recess 15e recessed rearward from the tip surface of the core contact portion 15c. It is preferable that the depth of the concave portion 15e along the axial direction is 2 mm or more.

When there is a spare lead 91 in the lead tank 8, the leading end of the lead contact portion 15c of the display body 15 is in contact with the rear end of the spare lead 91 as shown in FIG. 10A. When the remaining length of the core 9 is reduced, the rear end of the core 9 is positioned forward of the rear end of the chuck 11, as shown in FIG. 10B, as in the modification described with reference to FIGS. As shown, the front end of pre-core 91 can enter chuck 11 .

In this state, when the core 9 is retracted to store it, the spare core 91 is also retracted by being pushed by the core 9. - 特許庁In this modification, a concave portion 15e is formed at the tip of the core contact portion 15c of the display body 15. As shown in FIG. Therefore, the rear end of the spare core 91 can enter the recess 15e and retreat along the axial direction. As a result, the spare lead 91 can be retracted rearward from the state in which the lead contact portion 15 c of the display body 15 is in contact with the rear end of the spare lead 91 . In particular, when the depth of the concave portion 15e along the axial direction is 0.5 mm or more, the spare core 91 is shifted from the state in which the core contact portion 15c of the display body 15 is in contact with the rear end of the spare core 91. It is preferable because it can be retracted backward by 0.5 mm or more. Further, when the depth of the concave portion 15e along the axial direction is 2 mm or more, the spare lead 91 moves backward from the state in which the lead contact portion 15c of the display body 15 contacts the rear end of the spare lead 91. It is more preferable because it can be retracted by 2 mm or more.

11A to 11C are longitudinal sectional views showing still another modification of the mechanical pencil 1. FIG. In FIGS. 11A to 11C, dashed lines indicate the axial position of the tip of the core contact portion 15c in FIG. 11A.

In the example shown in FIGS. 11A to 11C, a relief portion 15d is formed at the tip of the core contact portion 15c of the display body 15. As shown in FIG. In the illustrated example, the relief portion 15d includes an inclined surface 15f provided at the tip of the core contact portion 15c. The slope 15f is inclined with respect to both the axial direction and the radial direction. The distance along the axial direction between the most forward point and the most rearward point on the slope 15f is preferably 2 mm or more.

When there is a spare lead 91 in the lead tank 8, the tip of the lead contact portion 15c of the display body 15 is in contact with the rear end of the spare lead 91 as shown in FIG. 11A. When the remaining length of the core 9 is reduced, the rear end of the core 9 is positioned forward of the rear end of the chuck 11, as shown in FIG. As shown, the front end of pre-core 91 can enter chuck 11 .

In this state, when the core 9 is retracted to store it, the spare core 91 is also retracted by being pushed by the core 9. - 特許庁In this modification, a slope 15 f is formed at the tip of the core contact portion 15 c of the display body 15 . Therefore, the rear end of the spare core 91 can retreat along the slope 15f. As a result, the spare lead 91 can be retracted rearward from the state in which the lead contact portion 15 c of the display body 15 is in contact with the rear end of the spare lead 91 . In particular, when the distance along the axial direction between the frontmost point and the rearmost point on the slope 15f is 0.5 mm or more, the spare lead 91 is positioned at the lead contact portion of the display body 15. 15c can be retracted rearward by 0.5 mm or more from the state in which it is in contact with the rear end of the spare core 91, which is preferable. Further, when the distance along the axial direction between the frontmost point and the rearmost point on the inclined surface 15f is 2 mm or more, the spare lead 91 is positioned so that the lead contact portion 15c of the display body 15 It is more preferable because it is possible to retreat 2 mm or more rearward from the state of contact with the rear end of the spare core 91 .

11A to 11C, with the front end of the spare lead 91 entering the chuck 11, it is retracted to accommodate the lead 9 in use, and is pushed by the lead 9. When the spare lead 91 is also retracted, the position of the spare lead 91 is radially displaced from the axis of the lead 9 (on the central axis of the mechanical pencil 1). , the state in which the core 9 and the spare core 91 are arranged in series along the axial direction is eliminated. Therefore, the retraction of the core 9 is prevented, and the breakage of the spare core 91 by being pushed by the core 9 is prevented.

As a further modified example of each modified example described with reference to FIGS. 9A to 11C, at least the core contact portion 15c of the display body 15 may be formed of a flexible material or an elastic member such as a spring. good. In this case, with the front end of the spare core 91 entering the chuck 11, the core 9 in use is retracted to accommodate it. By deforming the contact portion 15c, the rear end of the spare core 91 can be retracted. As a result, the spare lead 91 can be retracted rearward from the state in which the lead contact portion 15 c of the display body 15 is in contact with the rear end of the spare lead 91 . In particular, the material forming the core contact portion 15 c and the shape of the core contact portion 15 c are such that the preliminary core 91 is positioned rearward from the state in which the core contact portion 15 c of the display body 15 is in contact with the rear end of the preliminary core 91 . It is preferably selected so that it can be retracted to 0.5 mm or more. Furthermore, the material forming the core contact portion 15c and the shape of the core contact portion 15c are such that the preliminary core 91 is positioned backward from the state in which the core contact portion 15c of the display body 15 is in contact with the rear end of the preliminary core 91. More preferably, it is selected so that it can be retracted by 2 mm or more.

In the modifications described with reference to FIGS. 9A to 11C and further modifications of the modifications described above, the spare core 91 is such that the core contact portion 15c of the display body 15 is positioned behind the spare core 91. It is possible to retreat backward from the state in which it is in contact with the end. As a result, the spare lead 91 can be retracted rearward from the state in which the lead contact portion 15 c of the display body 15 is in contact with the rear end of the spare lead 91 . Therefore, it is possible to prevent the core 9 from being prevented from retreating due to the position of the spare core 91 behind the core 9 and to prevent the spare core 91 from being pushed by the core 9 and broken. Preferably, the spare lead 91 can be retracted rearward by 0.5 mm or more from the state where the lead contact portion 15c of the display body 15 is in contact with the rear end of the spare lead 91 . More preferably, the spare lead 91 can be retracted rearward by 2 mm or more from the state where the lead contact portion 15c of the display body 15 is in contact with the rear end of the spare lead 91 . In this case, since the spare core 91 is positioned behind the core 9, the core 9 is prevented from retreating, and the breakage of the spare core 91 due to being pushed by the core 9 is more effectively prevented.

FIG. 12 is a longitudinal sectional view showing still another modification of the mechanical pencil 1. As shown in FIG. FIG. 12 shows the mechanical pencil 1 with the tip opening 3a facing upward. In the illustrated example, the spring 16 is omitted compared to the embodiment described with reference to FIG. In other words, the mechanical pencil 1 shown in FIG. 12 does not have the spring 16. In this case, the display body 15 retreats due to its own weight when the tip opening 3a is directed upward. In the mechanical pencil 1 according to this modification, the front end of the lead contact portion 15c of the display body 15 is positioned inside the lead tank 8 when the display body 15 is in the most retracted state. That is, the front end of the lead contact portion 15c does not come off the lead tank 8 no matter where the display body 15 is placed. Such a configuration can be realized by appropriately setting the axial length of the core contact portion 15c.

Inside the lead tank 8 , dust may be generated by scratching the lead 9 and the spare lead 91 . According to the mechanical pencil 1 of this modified example, it is possible to prevent such dust from leaking out of the lead tank 8 even when the tip opening 3a faces upward and the display body 15 is in the most retracted state. Therefore, it is possible to prevent the mechanical pencil 1 from being soiled by dust.

FIG. 13 is a longitudinal sectional view showing still another modification of the mechanical pencil 1. As shown in FIG. In the illustrated mechanical pencil 1, the barrel body 2 has a first portion 2c and a second portion 2f arranged behind the first portion 2c. are detachable from each other. The first portion 2c and the second portion 2f each have a substantially cylindrical shape as a whole. A male screw portion 2d is provided on the front outer side of the first portion 2c, and a fitting portion 2e is provided on the rear outer side of the first portion 2c. The first portion 2c is attached to the tip 3 by screwing the male threaded portion 2d of the first portion 2c into the female threaded portion 3b of the tip 3 . A fitting portion 2g is provided on the front inner side of the second portion 2f, and an engaging portion 2h is provided on the rear inner side of the second portion 2f. The second portion 2f is attached to the rear axle 4 by engaging the engaging portion 2h of the second portion 2f with the engaging portion 4c provided on the front outer side of the rear axle 4 . The fitting portion 2e of the first portion 2c and the fitting portion 2g of the second portion 2f are detachably fitted to each other. As a result, the first portion 2c and the second portion 2f are assembled together. With such a configuration, the mechanical pencil 1 of this modification is divided into the front portion 1a and the rear portion 1b between the fitting portion 2e of the first portion 2c and the fitting portion 2g of the second portion 2f. It is possible. In a state in which the mechanical pencil 1 is divided into the front portion 1a and the rear portion 1b, the lead tank 8 opens rearward within the front portion 1a.

The accessory holding member 6 extends axially through the rear barrel 4 and the second portion 2f of the barrel body 2, and the front end of the accessory holding member 6 extends from the front end of the second portion 2f. It protrudes forward. Engagement projections 6 e are provided on the outer surface of the accessory holding member 6 , and by engaging the engagement projections 6 e with the front end of the rear axle 4 , the accessory holding member 6 is attached to the rear axle 4 and the barrel body 2 . is prevented from exiting backwards from the In the illustrated example, the front end of the accessory holding member 6 is in a state in which the fitting portion 2e of the first portion 2c and the fitting portion 2g of the second portion 2f of the barrel body 2 are fitted to each other, that is, sharp The front part 1a and the rear part 1b of the pencil 1 abut on the rear end of the lead tank 8 when assembled with each other.

The length of the core contact portion 15c of the display body 15 in the axial direction is such that the front end of the core contact portion 15c of the display body 15 extends from the accessory holding member 6 when the display body 15 is positioned at the frontmost position. It has a length that does not protrude forward from the front end. In particular, in the example shown in FIG. 13, when the display body 15 is positioned at the frontmost position, the front end of the core contact portion 15c of the display body 15 and the front end of the accessory holding member 6 are positioned in the axial direction. They are in approximately the same position.

In this modification, when replenishing the lead 9 (preliminary lead 91) in the lead tank 8, first, the fitting portion 2e of the first portion 2c of the barrel body 2 and the fitting portion 2g of the second portion 2f are , the mechanical pencil 1 is divided into a front portion 1a and a rear portion 1b. As a result, the lead tank 8 is opened rearward within the front portion 1a. Next, the lead 9 (preliminary lead 91) is inserted into the lead tank 8. As shown in FIG. After that, the fitting portion 2e of the first portion 2c and the fitting portion 2g of the second portion 2f of the barrel body 2 are fitted to each other, thereby assembling the front portion 1a and the rear portion 1b to each other.

According to the mechanical pencil 1 of this modified example, even if the mechanical pencil 1 is divided into the front portion 1a and the rear portion 1b when replenishing the lead 9 (the spare lead 91) in the lead tank 8, the display body 15 The front end of the lead contact portion 15c does not protrude forward from the front end of the accessory holding member 6. As shown in FIG. As a result, when the lead tank 8 is replenished with the lead 9 (preliminary lead 91), the lead abutting part 15c is not exposed to the outside, and the lead abutting part 15c, which is a relatively thin member, is not exposed to other members. It is possible to prevent bending or breaking by contact. In addition, since it is not necessary to remove the accessory holding member 6 from the barrel when refilling the lead 9 (the spare lead 91) into the lead tank 8, the accessory holding member 6 removed from the barrel may be damaged. It is possible to prevent it from being lost.

14A is a longitudinal sectional view showing a modified example of the rear barrel 4 of the mechanical pencil 1, and FIG. 14B is a transverse sectional view corresponding to the CC line of FIG. The rear axle 4 is shown with the retaining member 6 inserted. On the inner surface of the rear shaft 4 of this modification, a cam portion 4d including a cam slope extending spirally along the inner surface in the axial direction and the circumferential direction, an engaging groove 4e extending along the axial direction, is formed. In the illustrated example, two cam portions 4d are provided 180 degrees apart in the circumferential direction, and two engaging grooves 4e are provided 180 degrees apart in the circumferential direction. One cam portion 4d includes a first cam slope 4d1 that is inclined to one side in the circumferential direction with respect to the axial direction and faces rearward, and a first cam slope face 4d1 that is inclined to the other side in the circumferential direction with respect to the axial direction and faces rearward. and a second cam slope 4d2. The accessory holding member 6 also has two engaging projections 6b spaced apart by 180 degrees in the circumferential direction.

In this modified example, when the accessory holding member 6 is inserted into the rear axle 4 from behind, each engagement projection 6b of the accessory holding member 6 comes into contact with the first inclined cam surface 4d1 or the second inclined cam surface 4d2 of the cam portion 4d. It contacts and is guided toward each engagement groove 4e. Therefore, even if the accessory holding member 6 is inserted into the rear axle 4 without precisely aligning the engagement projections 6b and the engagement grooves 4e, the engagement projections 6b and the engagement grooves 4e are not aligned. and will mesh smoothly. Therefore, the attachment/detachment of the accessory holding member 6 to/from the barrel is improved.

15A and 15B are longitudinal sectional views showing still another modification of the mechanical pencil 1. FIG. In this modified example, a convex portion 6f is provided on the rear outer surface of the fitting portion 6a of the accessory holding member 6. As shown in FIG. The convex portion 6f is formed in an annular shape along the circumferential direction. The outer diameter of the projection 6f is slightly larger than the minimum inner diameter of the rear axle 4 (the inner diameter of the front portion). As a result, the projection 6f passes through the smallest inner diameter portion (front portion) of the rear barrel 4 when a relatively large force acts on the attachment holding member 6 along the axial direction due to the user's operation. However, when a relatively small force such as the weight of the cap 5, the accessory holding member 6, and the eraser 7 acts on it, it cannot pass through the minimum inner diameter portion of the rear barrel 4. Further, when the fitting portion 6a of the accessory holding member 6 is completely inserted into the fitting portion 8a of the lead tank 8 (see FIG. 15A), the projection 6f and the front end of the rear barrel 4 move in the axial direction. is larger than the axial length of the fitting portion 6a.

According to such a mechanical pencil 1, when the fitting between the fitting portion 6a of the accessory holding member 6 and the fitting portion 8a of the lead tank 8 is released due to impact such as dropping (see FIG. 15B). Even so, it is possible to prevent the accessory holding member 6 from coming off the barrel. As a result, the spare lead 91 in the lead tank 8 does not spill out of the lead tank 8. - 特許庁Also, it is possible to prevent the attachment holding member 6 from being lost from the barrel.

15A and 15B, a marking portion is provided on the outer surface of the accessory holding member 6, and the fitting portion 6a of the accessory holding member 6 is connected to the fitting portion 8a of the lead tank 8. When the fitting portion 6a is completely inserted into the fitting portion 8a, the marking portion cannot be visually recognized by the user. can be In this case, the user can recognize that attachment of the accessory holding member 6 to the shaft cylinder is insufficient by visually recognizing the marking portion. The specific form of the marking portion is not particularly limited.

As another modification, the front surface and/or the back surface of the window 2b may have a polyhedral shape. For example, the front surface and/or the rear surface of the window 2b may have a diamond-cut shape. As a result, the appearance of the display 15 is improved, and the presence or absence of the spare lead 91 in the lead tank 8 can be easily confirmed.

As another modification, when the lead tank 8 has a spare lead 91, the display body 15 can be seen through the window 2b. The inner wall surface of the may be visible. In this case, it is preferable that the inner wall surface of the core tank 8 and the inner wall surface of the shaft cylinder be colored in a color that is easy to distinguish from the display portion 15b of the display body 15 and visually recognizable.

1... mechanical pencil, 1a... front portion, 1b... rear portion,
2... Axle tube main body 2a... Engagement groove 2b... Window part 2c... First part 2d... Male screw part 2e... Fitting part 2f... Second part 2g... Fitting part 2h... Engagement Aibe,
3... tip, 3a... tip opening, 3b... female screw part,
4 Rear shaft 4a Rear end opening 4b Engagement hole 4c Engagement portion 4d Cam portion 4d1 First cam slope 4d2 Second cam slope 4e Engagement groove
5... cap, 5a... female screw part,
6... Attachment holding member 6a... Fitting portion 6b... Engagement projection 6c... Male screw portion 6d... Slit 6e... Engagement projection 6f... Convex portion
7 Eraser,
8... Core tank, 8a... Fitting part,
9... core, 91... spare core,
DESCRIPTION OF SYMBOLS 10... Connector, 10a... Male screw part, 11... Chuck, 11a... Chuck head,
12... Fastener, 13... Chuck spring, 14... Core holder,
Reference numeral 15: display body 15a: projecting portion 15b: display portion 15c: core contacting portion 15d: relief portion 15e: recessed portion 15f: inclined surface;
16... Spring,
21... Front shaft 21a... Male threaded portion 21b... Female threaded portion
22... inner shaft, 22a... male screw portion, 22b... engagement projection, 22c... window portion.

Claims (6)

A shaft cylinder having a tip opening from which a wick protrudes and a rear end opening for replenishing the wick, a wick tank built in the shaft cylinder, and a wick tank positioned in front of the wick tank and interlocking with the wick tank. a chuck spring for urging the chuck and the lead tank rearward; an accessory; an accessory holding member positioned behind the lead tank and holding the accessory; a mechanical pencil having an operating portion located at the rear and protruding from the rear end opening of the barrel, and operating the operating portion to advance the chuck interlocked with the operating portion to extend the lead. A display body is disposed in the shaft cylinder so as to be in contact with the rear end of the lead housed in the lead tank so as to be movable back and forth in the axial direction of the mechanical pencil, and the last lead in the lead tank. As the lead moves forward, the display body in contact with the rear end of the spare lead follows and moves forward. The display body is inserted into and removed from the lead tank and accommodated in the lead tank. When the width of the display portion is X and the width of the core contact portion is Y when the window portion is viewed from the front with the axial direction of the mechanical pencil up and down, X and Y satisfy the relational expression X>Y. The display body is loosely attached to the accessory holding member, and in a state in which the accessory holding member is attached to the barrel or the core tank, the display is positioned in the barrel and moves back and forth in the axial direction. 2. The mechanical pencil according to claim 1, wherein the display body is also removed from the barrel by detaching the accessory holding member from the barrel or the lead tank. 3. The mechanical pencil according to claim 1, wherein said window is formed by forming a transparent or translucent part of said barrel. 4. The mechanical pencil according to any one of claims 1 to 3, wherein said display body is biased toward said tip opening of said barrel by an elastic member. 5. The mechanical pencil according to any one of claims 1 to 4, wherein said spare lead can be retracted rearward from a state in which said lead abutting portion of said display is in contact with the rear end of said spare lead. 6. The mechanical pencil according to any one of claims 1 to 5, wherein a front end of said lead abutting portion is positioned within said lead tank when said display body is in the most retracted state.

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