JP2021094796A - mechanical pencil - Google Patents

Abstract

To provide a mechanical pencil that can form a state in which even a writing core with a small diameter does not pass through.SOLUTION: The mechanical pencil P includes a unit component 40 that forms a guide path R40 that guides the writing core. Here, at least a part of the guide path R40 is formed by a gap G of a plurality of parts 1 and 2 which are separate from each other and are arranged while providing the gap G, and can be switched between a state in which the gap G is smaller than the diameter of the writing core and a state in which the gap G is larger than the diameter of the writing core.SELECTED DRAWING: Figure 8

Description

The present invention relates to mechanical pencils.

As is well known, a mechanical pencil is a writing instrument used by feeding out a thin writing core formed of graphite or the like. In a general knock-type mechanical pencil, a core tank capable of accommodating a plurality of writing wicks is arranged in a shaft which is a tubular member, and a writing wick is placed on one end side (front end side) of the wick tank. A feeding mechanism is provided for feeding the paper, and a knock member for operating the feeding mechanism is provided on the other end side (rear end side).

In a general mechanical pencil having such a configuration, the knock member often also serves as a cap for closing the opening at the rear end of the lead tank, and when filling the mechanical pencil with the writing lead. The user removes the knock member from the lead tank and inserts the writing lead through the opening at the rear end.

However, the knock member removed from the core tank is easily lost, and there is a risk that the child may accidentally swallow it. Therefore, Patent Document 1 proposes a knock member that can fill the core tank with the writing core without removing it from the core tank while blocking the writing core from coming out of the core tank.

The knock member described in Patent Document 1 is a tubular member, and a member called a guide member is further provided inside the tubular member. This guide member is a member in which a writing core passage for passing the writing core is formed inside, and has a plurality of elastic piece portions extending forward. When the user does not apply an external force, the plurality of elastic pieces block the opening at the front end of the writing core passage, and the writing core cannot pass through the opening, whereby the writing core in the core tank cannot pass through. Is not going out. Then, when the user applies an external force that pushes the guide member forward, the guide member moves forward with respect to the knock member, and a plurality of elastic piece portions open outward (expand) accordingly. It is elastically deformed. That is, the opening area at the front end of the writing core passage increases due to the elastic deformation of the elastic piece portion. This allows the writing core to pass through the writing core passage. Therefore, the user does not have to bother to remove the knock member, but simply pushes the guide member forward with the writing core inserted from the opening at the rear end of the writing core passage to fill the core tank with the writing core. be able to.

According to such a configuration, since it is not necessary to remove the knock member as a cap from the core tank, the writing core can be quickly filled without any trouble, and the filled writing core can be discharged from the core tank. Can also be prevented. In addition, the removed knock member will not be lost. Such a configuration is also called a capless speed-in mechanism or the like.

Japanese Patent No. 5146863

As described above, the mechanical pencil described in Patent Document 1 is capable of switching between a state in which the writing core is passed and a state in which the writing core is not passed by elastically deforming a plurality of elastic piece portions included in the guide member. In order to prevent the writing core from passing reliably in the above state, the opening area of the writing core passage defined by the separation distance between the elastic pieces is smaller than that of the writing core in the state where no external force is applied. You need to be. That is, it is necessary to form a guide component in which a plurality of elastic piece portions are arranged close to each other with a gap smaller than the diameter of the writing core.

When such a guide part is manufactured by, for example, resin molding using a mold, a portion corresponding to a gap between a plurality of elastic piece portions is molded by a pin member or the like. However, in order to obtain a guide member capable of supporting a writing core having a small diameter such as 0.3 mm or 0.5 mm, it is necessary to prepare a pin having a smaller diameter than such a writing core having a small diameter. In reality, it is necessary to take dimensional tolerances into consideration, and it is very difficult in reality to create such a small-diameter pin and a mold having high dimensional accuracy corresponding to the pin.

Due to such circumstances, in reality, in the configuration as in Patent Document 1, only a mechanical pencil corresponding to a writing core having a relatively large diameter could be obtained.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a mechanical pencil capable of forming a state in which even a writing core having a small diameter does not pass through the writing core.

The present invention has taken the following measures in order to achieve such an object.

That is, the present invention is a mechanical pencil.
Unit parts that form a guide path to guide the writing core,
With
In the unit parts
At least a portion of the guideway is formed by the gaps of a plurality of parts that are separate from each other and are arranged with a gap.
It is possible to switch between a state in which the gap is smaller than the diameter of the writing core and a state in which the gap is larger than the diameter of the writing core.
It is characterized by that.

According to this configuration, at least a part of the guide path is formed by a gap provided between a plurality of parts that are separate from each other, so that a gap smaller than the diameter of the small-diameter writing core can be easily formed. it can. Therefore, it is possible to form a state in which even a writing core having a small diameter does not pass through the writing core.

Preferably, in the mechanical pencil,
The plurality of parts are two parts.
It is characterized by that.

According to this configuration, the number of parts can be reduced.

Preferably, in the mechanical pencil,
The unit component is attached to the rear end of a core tank for accommodating a writing core, and is configured so that the writing core that has passed through the gap is filled in the core tank.
It is characterized by that.

According to this configuration, by making the gap larger than the diameter of the writing core, the writing core can be filled in the core tank via the guide path, and the gap is made smaller than the diameter of the writing core. As a result, the writing core filled in the core tank can be closed so as not to go out. Therefore, when filling the writing lead, it is not necessary to remove the member that functions as the cap of the lead tank (that is, the knock member in a conventional general mechanical pencil), which saves time and effort.

Preferably, in the mechanical pencil,
The first part, which is one of the plurality of parts, is a tubular part.
A second component, which is another one of the plurality of components, is arranged inside the cylinder of the first component.
The gap is formed by a part of the inner wall surface of the first part and a part of the second part.
It is characterized by that.

According to this configuration, a gap is formed between the tubular first component and the second component arranged inside the cylinder, so that the configuration can be simplified.

Preferably, in the mechanical pencil,
The second part is
An elastic piece arranged with the gap between it and the inner wall surface of the first component.
With
The size of the gap changes due to elastic deformation of the elastic piece.
It is characterized by that.

According to this configuration, the size of the gap can be changed by a simple operation such as elastically deforming the elastic piece. That is, it is possible to switch between a state in which the writing core can pass and a state in which the writing core cannot pass by a simple operation.

Preferably, in the mechanical pencil,
The elastic piece is configured to be elastically deformed by the relative movement of the second component in the axial direction of the first component.
It is characterized by that.

According to this configuration, the size of the gap can be changed by a simple operation of relatively moving the second component in the axial direction of the first component.

Preferably, in the mechanical pencil,
The second part is a tubular part, and a plurality of slits extending in the axial direction are arranged at the end thereof in the circumferential direction, whereby a plurality of extending pieces are formed at the end. ,
By moving the second component relative to the axial direction of the first component, the tips of the plurality of extension pieces are elastically deformed in a direction in which they are separated from each other.
At least one of the plurality of extension pieces forms the elastic piece.
It is characterized by that.

According to this configuration, the second component is elastically deformed in a well-balanced manner, and the elastic piece is elastically deformed accordingly, so that the size of the gap can be stably switched.

According to the present invention, it is possible to obtain a mechanical pencil that can form a state in which even a writing core having a small diameter does not pass through the writing core.

The side view which shows the whole structure of the mechanical pencil which concerns on embodiment of this invention. A side sectional view of the mechanical pencil shown in FIG. FIG. 2 is an enlarged view showing a front end portion of the mechanical pencil shown in FIG. Side view and side sectional view of the guide part. A side view and a cross-sectional view showing the tip portion of the guide component in an enlarged manner. Side view and side sectional view of the knock part. A side view and a cross-sectional view showing the tip portion of the knock part in an enlarged manner. A side sectional view showing a state in which the guide component 2 and the like are housed in the knock component 1.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<1. Configuration>
The configuration of the mechanical pencil according to the embodiment will be described with reference to FIGS. 1 to 3. FIG. 1 is a side view showing the overall configuration of the mechanical pencil P according to the embodiment. FIG. 2 is a side sectional view of the mechanical pencil P shown in FIG. 1 cut along a plane including the axial direction. FIG. 3 is an enlarged view showing a front end portion of the mechanical pencil P in FIG. 2.

In the following description, the side on which the writing core D is sent out is referred to as the "front end" and the opposite side is referred to as the "rear end" in the axial direction of the mechanical pencil P. Further, the radial direction of the circle centered on the axis on the plane orthogonal to the axial direction of the sharp pencil P is called the "diameter direction", and the circumferential direction of the circle centered on the axis on the plane orthogonal to the axial direction of the sharp pencil P. Is called "circumferential direction". However, these directions are for convenience of explanation, and do not limit the directions when the mechanical pencil P is used.

The mechanical pencil P includes an outer cylinder 10, a core tank 20 housed inside the outer cylinder 10, a delivery mechanism 30 provided in front of the core tank 20, and a unit component 40 provided behind the core tank 20. To be equipped with.

(Outer cylinder 10)
The outer cylinder 10 is a member that forms the exterior of the mechanical pencil P, and includes a shaft portion 101, a tip 102, and a slider 103.

The shaft portion 101 is a long tubular member, and its cross section orthogonal to the axial direction is circular (may be polygonal, elliptical, or the like). Further, a grip or the like may be provided on the outer circumference of the shaft portion 101.

The tip 102 is a member in which a substantially conical portion whose diameter is reduced toward the front end and a substantially tubular portion are connected in the front-rear direction, and a through-passage R102 extending in the axial direction is formed inside the member. There is. The tip 102 is connected to the shaft portion 101 by press-fitting or screwing the tubular portion into the front end of the shaft portion 101. Then, when connected to the tip of the shaft portion 101, the rear end of the tubular portion is inserted between the double walls of the sleeve 304, which will be described later.

The slider 103 is a tubular member for protecting the writing core D from breaking, and is arranged at the front end portion of the gangway R102 formed in the tip 102 while allowing the sliding movement in the front-rear direction.

(Core tank 20)
The core tank 20 is a member for accommodating one or more filled writing cores D, and includes a main body portion 201 and a connecting portion 202.

The main body portion 201 is a long tubular member arranged inside the shaft portion 101, and the internal space thereof constitutes an accommodation space for accommodating a plurality of writing cores D. An annular protrusion 2011 extending in the circumferential direction is formed on a part of the inner wall of the main body 201 to prevent the writing core D housed therein from adhering to the inner wall of the main body 201 due to static electricity. ing. However, the protrusion 2011 is not an essential element and may be omitted.

The connecting portion 202 is a portion provided so as to close the front end of the main body portion 201, and a guide path (first guide path) R202 extending in the axial direction is formed inside the connecting portion 202. The first guide path R202 communicates with the internal space of the main body 201 at the rear end. The inner diameter of the first guideway R202 is slightly larger than the diameter of the writing core D, so that only one writing core D can pass through the first guideway R202 at a time. ing. The connecting portion 202 includes an extending portion 2022 protruding forward, which is connected to the rear end portion of the chuck 301, which will be described later.

(Sending mechanism 30)
The delivery mechanism 30 includes a chuck 301, a chuck ring 302, a chuck spring 303, and a sleeve 304.

The chuck 301 includes a main body portion 3011 which is a long tubular member. A guide path (second guide path) R301 extending in the axial direction is formed inside the main body portion 3011. The main body portion 3011 is connected to the connecting portion 202 of the core tank 20 at the rear end, and the second guide path R301 communicates with the first guide path R202. The diameter of the second guideway R301 is substantially the same as the diameter of the first guideway R202. A plurality of holding pieces 3012 are provided in front of the main body portion 3011 in succession with the main body portion 3011. The plurality of holding pieces 3012 are narrowed inward in the radial direction by fitting the chuck ring 302 described later into the tip portion thereof. When the chuck 301 is moved forward relative to the chuck ring 302, the plurality of holding pieces 3012 are released from the chuck ring 302 and expand outward in the radial direction.

The chuck ring 302 is an annular member, and is fitted to the outside of the tip portions of the plurality of holding pieces 3012 of the chuck 301 to narrow the tip portions of the plurality of holding pieces 3012 inward in the radial direction. The diameter of the chuck ring 302 is defined so that the separation distance of the tip portion of each holding piece 3012 is slightly smaller than the diameter of the writing core D when the chuck ring 302 is fitted from the outside. Therefore, in a state where the chuck ring 302 is fitted to the tip end portion of each holding piece 3012, the writing core D cannot pass through the second guide path R301. That is, when the writing core D does not exist in the second guide path R301, the new writing core D is stopped at the opening end in front of the second guide path R301, and the writing core D is in the second guide path R301. If it exists, the writing core D is sandwiched between the sandwiching pieces 3012 and stopped so that it cannot move back and forth.

The chuck spring 303 is a member formed of a coil spring or the like, and is arranged behind the chuck ring 302 to urge the core tank 20 and the chuck 301 connected to the core tank 20 to the rear.

The sleeve 304 is a tubular member having a double peripheral wall structure, and a main body portion 3011 of the chuck 301 is arranged in the inner peripheral wall while allowing slide movement in the front-rear direction. Further, the rear end of the tip 102 is inserted between the double walls of the sleeve 304. However, the sleeve 304 does not necessarily have to have a double structure as long as it holds the tip 102 while arranging the main body 3011 inside.

(Unit part 40)
The unit component 40 forms a guide path R40 for guiding the writing core D to be filled in the core tank 20, and is attached to the rear end of the core tank 20. The unit component 40 plays a role of blocking the writing core D filled in the main body 201 of the core tank 20 so as not to go out, and also plays a role of operating the delivery mechanism 30.

The unit component 40 includes a first component (hereinafter, also referred to as a “knock component”) 1 which is a tubular component, and a second component (hereinafter, also referred to as a “guide component”) 2 housed inside the cylinder. The knock component 1 serves as an outer member arranged outside the guide component 2. The knock component 1 and the guide component 2 are components that are separately formed from each other, and are combined to form a unit component 40.

(Guide part 2)
The guide component 2 will be described with reference to FIGS. 4 and 5. 4 and 5 are both views showing the guide component 2. Specifically, FIG. 4A is a side view of the guide component 2, and FIG. 4B is a side sectional view thereof. FIG. 4C is a view obtained by rotating FIG. 4A by 90 degrees around an axis, and FIG. 4D is a side sectional view thereof. FIG. 4 (e) is a view obtained by rotating FIG. 4 (a) by 180 degrees around the axis, and FIG. 4 (f) is a side sectional view thereof. FIG. 5 shows an enlarged view of the front end portion of FIG. 4 (d) and a cross-sectional view thereof as viewed from the direction of arrow A.

The guide component 2 is a substantially cylindrical component including a large diameter portion 21 having a relatively large outer diameter and a small diameter portion 22 having a relatively small outer diameter extending in front of the large diameter portion 21.

The inner wall of the guide component 2 constitutes a part of the peripheral wall of the guide path R40 for guiding the writing core D to be filled, and its diameter is slightly larger than the diameter of the writing core D. ing. However, the inner wall of the guide component 2 is an expanding surface 23 that gradually expands outward in the radial direction toward the rear in the vicinity of the opening end behind the guide component 2. As a result, the diameter of the rear opening end of the guide path R40 formed on the rear surface of the guide component 2 (that is, the introduction portion of the guide path R40) becomes larger than the diameter of the writing core D, and from here, the writing core D becomes larger. It is easy to put in.

Two slits 24 are formed in the small diameter portion 22 extending along the axial direction from the front end thereof to a position after the front-rear center. The two slits 24, 24 are formed at positions facing each other with the axis line interposed therebetween. As a result, the front side portion of the small diameter portion 22 is divided into substantially two equal parts in the circumferential direction around the axis, whereby two extension pieces 25 and 26 extending forward are formed in the front side portion. In the following, each extension piece 25, 26 formed by being divided by the slit 24 is referred to as an “elastic piece 25, 26”.

On the outer peripheral surface of each of the elastic pieces 25 and 26, a locking projection 27 projecting outward in the radial direction is provided. By accommodating the locking projection 27 in the through window 13 of the knock component 1 described later, the guide component 2 is locked so as not to fall out of the knock component 1.

The two elastic pieces 25 and 26 have different axial lengths. In the following, when distinguishing between the two elastic pieces 25 and 26, the relatively long elastic piece 25 is referred to as the "first elastic piece 25", and the relatively short elastic piece 26 is referred to as the "second elastic piece 26". It is called "elastic piece 26".

The inner peripheral surface of the first elastic piece 25 forms a part of the peripheral wall of the guide path R40, and the cross section orthogonal to the axis is substantially arcuate. The inner peripheral surface of the first elastic piece 25, which protrudes forward from the second elastic piece 26, includes a protrusion 251 protruding inward in the radial direction and a sliding surface 252 connected to the front thereof. Is provided.

The protruding side top surface 251a of the protruding portion 251 is a flat surface extending in the axial direction, extending in the chord direction when viewed from the axial direction, and projecting to the vicinity of the central axis of the guide path R40. Behind the top surface 251a, an inclined surface 251b that is radially outwardly inclined toward the rear is formed in connection with the top surface 251a. Further, in front of the top surface 251a, a wall surface 251c orthogonal to the axis is formed in connection with the top surface 251a.

The sliding surface 252 is a surface formed by cutting off the tip portion of the inner peripheral surface of the first elastic piece 25 in a substantially conical shape, and expands outward in the radial direction toward the front.

The inner peripheral surface of the second elastic piece 26, like the inner peripheral surface of the first elastic piece 25, forms a part of the peripheral wall of the guide path R40, and the cross section orthogonal to the axis is substantially arcuate. There is. At the tip of the inner peripheral surface of the second elastic piece 26, a step portion 261 and a sliding surface 262 connected in front of the step portion 261 are provided.

The step portion 261 is composed of a wall surface 261a orthogonal to the axis and a vertical wall surface 261b extending in front of the wall surface 261a. The vertical wall surface 261b is a flat surface extending in the axial direction, and extends in the chord direction when viewed from the axial direction.

The sliding surface 262 is a flat surface formed by obliquely cutting off the tip portion of the inner peripheral surface of the second elastic piece 26, which is inclined outward in the radial direction toward the front.

(Knock part 1)
The knock component 1 will be described with reference to FIGS. 6 to 8. 6 and 7 are both views showing the knock component 1. Specifically, FIG. 6A is a side view of the knock component 1, and FIG. 6B is a side sectional view thereof. FIG. 6 (c) is a view obtained by rotating FIG. 6 (a) by 90 degrees around an axis, and FIG. 6 (d) is a side sectional view thereof. FIG. 7 shows an enlarged view of a portion near the center of the front-rear direction of FIG. 6D, and a cross-sectional view of the portion near the center of the front-rear direction as viewed from the direction of arrow A. FIG. 8 is a side sectional view showing a state in which the guide component 2 and the like are housed in the knock component 1. FIG. 8A shows a state in which an external force is not applied to the guide component 2 and the guide component 2 is arranged at a rear position (hereinafter, also referred to as a “natural state”). On the other hand, FIG. 8B shows a state in which the guide component 2 is arranged at the front position (hereinafter, also referred to as “pushing state”) by applying an external force for pushing the guide component 2 forward. ..

The knock component 1 is a substantially cylindrical component including a large diameter portion 11 having a relatively large outer diameter and a small diameter portion 12 having a relatively small outer diameter extending in front of the large diameter portion 11.

The front portion of the internal space of the small diameter portion 12 is a space for accommodating the core tank 20. This portion is composed of a small-diameter inner wall portion 121 having a relatively small inner diameter and a large-diameter inner wall portion 122 having a relatively large inner diameter provided in front of the small-diameter inner wall portion 121, and is surrounded by the small-diameter inner wall portion 121. The knock component 1 is attached to the rear end of the main body 201 by fitting the rear end portion of the main body 201 of the core tank 20 (FIG. 8). The rear end surface of the small-diameter inner wall portion 121 communicates with the opening end in front of the guide path R40 (that is, the lead-out portion of the guide path R40) so that the writing core D passing through the opening end surface is filled in the main body portion 201. It has become.

On the other hand, the rear portion of the internal space of the large diameter portion 11 and the internal space of the small diameter portion 12 forms a space for accommodating the guide component 2 and forms a part of the peripheral wall of the guide path R40.

A pair of through windows 13 and 13 extending in the axial direction are formed in the vicinity of the rear end of the small diameter portion 12 at positions facing each other with the axis line interposed therebetween. Further, on the inner wall of the small diameter portion 12, a pair of convex strip portions 14 and 14 extending in the axial direction are formed at positions facing each other with the axis line interposed therebetween. The rear end portion of each convex portion 14 has a shape that protrudes inward in the radial direction while drawing a gentle curve toward the front. The pair of through windows 13 and 13 and the pair of ridges 14 and 14 are arranged on a plane forming 90 degrees with each other.

In a state where the guide component 2 is housed inside the knock part 1, the locking projection 27 of the guide part 2 is housed in the through window 13 and the ridge portion 14 is housed in the slit 24 (FIG. 8). .. By accommodating the locking projection 27 of the guide component 2 in the through window 13, the guide component 2 is locked so as not to fall out of the knock component 1. However, the front-rear length of the through window 13 is set to be sufficiently long with respect to the locking projection 27, whereby the guide part 2 is allowed to slide back and forth inside the knock part 1. The window. Further, by accommodating the ridge portion 14 in the slit 24, it is possible to avoid a situation in which the writing core D inserted from the rear opening end of the guide path R40 enters the slit 24 and is caught laterally. Slit. That is, the ridge portion 14 serves as a wall for preventing the writing core D from entering the slit 24 and being caught.

The rear portion of the small diameter portion 12 in the internal space is divided into approximately two equal parts in the circumferential direction by a pair of convex protrusions 14, 14, and the first space (first accommodation space) R12a is divided into two equal parts. The elastic piece 25 is housed, and the second elastic piece 26 is housed in the other space (second housed space) R12b. Further, in front of the first accommodation space R12a and the second accommodation space R12b, a substantially columnar space (communication space) R12c connected to the first accommodation space R12a is formed. The inner diameter of the communication space R12c is larger than the diameter of the writing core D.

On the surface (front end surface of the first accommodation space R12a) H1 formed between the front edge of the peripheral wall of the first accommodation space R12a and the trailing edge of the peripheral wall of the communication space R12c, a guide protrusion (a guide protrusion) protruding rearward ( The first guide protrusion) 15 is provided.

The protruding side top surface 15a of the first guide protrusion 15 is a flat surface orthogonal to the axis, and extends in an arc shape when viewed from the axial direction. The radial inner edge of the top surface 15a is connected to the first wall surface 15b extending parallel to the axis, and this is continuously connected to the peripheral wall of the connected space R12c. Further, the radial outer edge of the top surface 15a is connected to a conical side surface inclined surface 15c that expands radially outward as it goes forward. The radial outer edge of the inclined surface 15c is connected to the second wall surface 15d extending parallel to the axis.

The inclined surface 15c of the first guide protrusion 15 abuts on the sliding surface 252 of the first elastic piece 25 and serves as a guide surface for guiding the sliding surface 252. Further, the top surface 15a of the first guide protrusion 15 abuts on the wall surface 251c of the protrusion 251 of the first elastic piece 25 and serves as a locking surface for locking the wall surface 251c. That is, when the guide component 2 (FIG. 8 (a)) in the natural state moves relative to the knock component 1 by applying an external force that pushes the guide component 2 forward, the first elastic piece 25 moves forward in the first accommodation space R12a. At this time, the sliding surface 252 is guided by the inclined surface 15c, so that the tip of the first elastic piece 25 is elastically deformed outward in the radial direction. Then, when the movement proceeds to a certain point, the wall surface 251c comes into contact with the top surface 15a and is locked so that the first elastic piece 25 cannot move further forward (FIG. 8B).

On the other hand, a guide protrusion projecting rearward on the surface (front end surface of the second accommodation space R12b) H2 formed between the front edge of the peripheral wall of the second accommodation space R12b and the trailing edge of the peripheral wall of the communication space R12c. A portion (second guide protrusion portion) 16 is provided.

The second guide protrusion 16 is a flat surface extending in the axial direction, and includes a first wall surface 16a extending in the chord direction when viewed from the axial direction. The rear end of the first wall surface 16a is connected to an inclined surface 16b that inclines outward in the radial direction toward the rear. The radial inward edge of the inclined surface 16b extends in the chord direction when viewed from the axial direction, and is continuous with the flat top surface 16c orthogonal to the axis. The top surface 16c is connected to the top surface 17a on the protruding side of the facing protrusion 17, which will be described later.

The inclined surface 16b of the second guide protrusion 16 abuts on the sliding surface 262 of the second elastic piece 26 and serves as a guide surface for guiding the sliding surface 262. Further, the top surface 16c of the second guide protrusion 16 abuts on the wall surface 261a of the step portion 261 of the second elastic piece 26 and serves as a locking surface for locking the wall surface 261a. That is, when the guide component 2 (FIG. 8 (a)) in the natural state moves relative to the knock component 1 by applying an external force that pushes the guide component 2 forward, the second elastic piece 26 moves forward in the second accommodation space R12b. At this time, the sliding surface 262 is guided by the inclined surface 16b, so that the tip of the second elastic piece 26 is elastically deformed outward in the radial direction. Then, when the movement proceeds to a certain point, the wall surface 261a comes into contact with the top surface 16c, and the second elastic piece 26 is locked so that it cannot move further forward (FIG. 8B).

On the inner wall of the small diameter portion 12, a protruding portion 17 projecting inward in the radial direction is formed at a position facing the protruding portion 251 of the first elastic piece 25 in a natural state with the axis line interposed therebetween. ..

The protruding side top surface 17a of the facing protrusion 17 is a flat surface extending in the axial direction, extending in the chord direction when viewed from the axial direction, and projecting to the vicinity of the central axis of the guide path R40. .. At the rear end portion of the top surface 17a, a notch surface 171a which is formed by notching this in a substantially conical shape and which expands radially outward toward the rear is formed. Further, in front of the top surface 17a, a wall surface 17b orthogonal to the axis is formed in connection with the top surface 17a.

The facing protrusion 17 faces the protrusion 251 in a state where the first elastic piece 25 is housed in the first storage space R12a. Both the protruding side top surface 17a of the facing protrusion 17 and the protruding side top surface 251a of the protrusion 251 are flat surfaces extending in the axial direction and extend in the chord direction when viewed from the axial direction. Then, it overhangs to the vicinity of the central axis of the guide path R40. That is, these double-sided surfaces 17a and 251a are parallel surfaces to each other, and are arranged so as to face each other with a gap G provided between them. This gap G forms an open end (that is, a lead-out portion of the guide path R40) in front of the guide path R40 or a portion in the vicinity thereof. That is, in this mechanical pencil P, the lead-out portion (or a portion in the vicinity thereof) of the guide path R40 is formed by a gap G provided between the knock component 1 and the guide component 2, which are separate bodies.

The size of the gap G (that is, the distance between the top surface 17a of the facing protrusion 17 and the top surface 251a of the protrusion 251) is such that the guide component 2 is relatively moved back and forth with respect to the knock component 1. And it changes. That is, when the guide component 2 is relatively moved back and forth with respect to the knock component 1, the opening area of the lead-out portion (or a portion in the vicinity thereof) of the guide path R40 changes.

That is, when the guide component 2 is in the natural state (FIG. 8A), the size of the gap G is smaller than the diameter of the writing core D. Therefore, in this state, the writing core D cannot pass through the guide path R40. That is, when the writing core D does not exist in the guide path R40, the new writing core D cannot pass through the guide path R40 and is stopped behind the gap G, and the writing core D exists in the guide path R40. In this case, the writing core D is sandwiched between the knock component 1 and the guide component 2 in the gap G and is stopped so as not to move back and forth.

From here, when an external force that pushes the guide component 2 forward is applied and the guide component 2 in the natural state moves forward relative to the knock component 1, the elastic pieces 25 and 26 move their tips. It moves forward in each of the accommodation spaces R12a and R12b while elastically deforming outward in the radial direction (that is, elastically deforming in the direction in which the tips are separated from each other). As a result, the top surface 251a on the protruding side of the protrusion 251 is moved in the direction away from the top surface 17a on the protruding side of the facing protrusion 17, and the gap G is increased. Then, when the elastic pieces 25 and 26 are locked so as not to move forward any more (FIG. 8B), the size of the gap G becomes larger than the diameter of the writing core D. Therefore, in this state, the writing core D can pass through the guide path R40.

<2. Mode of use of mechanical pencil P>
When filling the writing core D in the mechanical pencil P, the user first puts the mechanical pencil P in an upright posture with the front facing downward from the opening end of the guide path R40 on the rear surface of the guide component 2. Insert D. Then, the writing core D falls in the guide path R40. At this time, if the guide component 2 is in a natural state (FIG. 8A), the size of the gap G provided between the knock component 1 and the guide component 2 is smaller than the diameter of the writing core D. Therefore, the writing core D cannot pass through here and is stopped here. When the user pushes the upper end of the writing core D downward, the writing core D enters the gap G by being guided by the inclination of the inclined surface 251b of the protrusion 251 and the notch surface 171a of the facing protrusion 17. It is held here.

From this state, when the user pushes the guide component 2 forward, the guide component 2 is moved forward relative to the knock component 1. Then, the size of the gap G changes, and this becomes larger than the diameter of the writing core D. As a result, the holding by the gap G is released, and the writing core D can pass through the gap G. The writing core D that has passed through the guide path R40 is guided into the main body 201 of the core tank 20 and filled there.

After that, when the user releases the application of the external force to the guide component 2, the guide component 2 elastically returns, so that the guide component 2 moves backward relative to the knock component 1. Then, the size of the gap G changes again, which becomes smaller than the diameter of the writing core D, and the writing core D cannot pass through the guide path R40. As a result, the writing core D filled in the core tank 20 is stopped so as not to go out through the guide path R40.

Further, when writing is performed using the new writing core D filled in the core tank 20, the user first puts the mechanical pencil P in the same standing posture as described above. In this way, only one of the one or more writing wicks D filled in the main body 201 of the wick tank 20 passes through the first guideway R201 and reaches the front opening end of the second guideway R301. .. At this time, until the unit component 40 is pressed, the writing core D cannot pass through the open end in front of the second guide path R301 and is in a stopped state.

When the user presses the unit component 40 and moves it forward, the core tank 20 connected to the unit component 40 moves forward, and the chuck 301 connected to the core tank 20 compresses the chuck spring 303. While moving forward. Then, the plurality of holding pieces 3012 are released from the chuck ring 302 and expand outward in the radial direction. As a result, the writing core D can pass through the opening end in front of the second guide path R301, and the writing core D moves forward in the second guide path R301.

After that, when the user releases the pressing of the unit component 40, the chuck spring 303 is urged to move the core tank 20 and the chuck 301 connected to the core tank 20 to the original rear position again. Then, the plurality of holding pieces 3012 are fitted to the chuck ring 302 and are narrowed inward in the radial direction. As a result, the writing core D cannot pass through the open end in front of the second guide path R301, and the writing core D cannot move back and forth. By repeating pressing and releasing the unit component 40 in this way, the writing core D is sent out to the slider 103, and the writing core D slides the slider 103 forward and moves it to the tip 102. It protrudes from the tip of the slider 103 while protruding from the tip of the opening. In this state, the user can write.

<3. Effect>
The mechanical pencil P according to the above embodiment includes a unit component 40 that forms a guide path R40 that guides the writing core D. Then, in the unit component 40, at least a part of the guide path R40 (in the above embodiment, the lead-out portion of the guide path R40 or a portion in the vicinity thereof) is arranged while providing a gap G, and is separate from each other. A state in which the gap G of a plurality of parts (knock part 1 and a guide part 2) is formed by the gap G, and the gap G is smaller than the diameter of the writing core D, and a state in which the gap G is larger than the diameter of the writing core D. It is switchable.

According to this configuration, at least a part of the guide path R40 is formed by a gap G provided between a plurality of parts 1 and 2 which are separate from each other, and therefore has a small diameter such as 0.3 mm or 0.5 mm. A gap G smaller than the diameter of the writing core D can be easily formed. Therefore, it is possible to form a state in which even a writing core D having a small diameter does not pass through the writing core D. That is, it is possible to realize a capless speed-in mechanism that can handle not only so-called thick cores but also so-called thin cores.

Further, in the mechanical pencil P according to the above embodiment, the above-mentioned plurality of parts are two parts (knock part 1 and guide part 2).

According to this configuration, the number of parts can be reduced.

Further, in the mechanical pencil P according to the above embodiment, the unit component 40 is attached to the rear end of the core tank 20 for accommodating the writing core D, and the writing core D that has passed through the gap G is the core tank. It is configured to be filled in 20.

According to this configuration, by setting the gap G to be larger than the diameter of the writing core D, the writing core D can be filled in the core tank 20 via the guide path R40, and the gap G can be filled with the diameter of the writing core D. By making it smaller than that, the writing core D filled in the core tank 20 can be closed so as not to go out. Therefore, when filling the writing lead D, it is not necessary to remove the member that functions as the cap of the lead tank 20 (that is, the knock member in a conventional general mechanical pencil), which saves time and effort.

Further, in the mechanical pencil P according to the above embodiment, the knock part (first part) 1 which is one of the plurality of parts 1 and 2 described above is a tubular part, and the plurality of parts 1 , 2 The guide part (second part) 2 which is another one is arranged inside the cylinder of the knock part 1. Then, a part of the inner wall surface of the knock component 1 (specifically, the top surface 17a of the facing protrusion 17) and a part of the guide part 2 (specifically, the top surface 251a of the protrusion 251 of the first elastic piece 25). ) And the gap G is formed.

According to this configuration, the gap G is formed by the tubular knock component 1 and the guide component 2 arranged inside the cylinder, so that the configuration can be simplified.

Further, in the mechanical pencil P according to the above embodiment, the guide component 2 includes an elastic piece 25 arranged so as to provide a gap G between the mechanical pencil P and the inner wall surface of the knock component 1, and the elastic piece 25 is elastically deformed. By doing so, the size of the gap G changes.

According to this configuration, the size of the gap G can be changed by a simple operation such as elastically deforming the elastic piece 25. That is, it is possible to switch between a state in which the writing core D can pass and a state in which the writing core D cannot pass by a simple operation.

Further, in the mechanical pencil P according to the above embodiment, the elastic piece 25 is elastically deformed by the relative movement of the guide component 2 in the axial direction of the knock component 1.

According to this configuration, the size of the gap G can be changed by a simple operation of relatively moving the guide component 2 in the knock component 1 axial direction.

Further, in the mechanical pencil P according to the above embodiment, the guide component 2 is a tubular component, and a plurality of slits 24 extending in the axial direction are arranged at the end thereof in the circumferential direction. A plurality of extension pieces (elastic pieces) 25, 26 are formed at the end portion, and the guide component 2 is relatively moved in the axial direction of the knock component 1, whereby the plurality of extension pieces 25, 26 of the plurality of extension pieces 25, 26 are formed. The tips are elastically deformed in the direction in which they are separated from each other. Then, at least one of the plurality of extension pieces 25, 26 forms the elastic piece 25.

According to this configuration, the guide component 2 is elastically deformed in a well-balanced manner, and the elastic piece 25 is elastically deformed accordingly. Therefore, the size of the gap G can be stably switched.

<4. Modification example>
In the above embodiment, two slits 24, 24 are formed at positions facing each other at the front end portion of the small diameter portion 22 of the guide component 2, whereby two extension pieces (elasticity) are formed in the portion. Pieces) 25 and 26 are assumed to be formed, but by arranging a plurality of three or more slits in the circumferential direction at the front end portion of the small diameter portion 22, three or more extending pieces are formed in the portion. (Elastic piece) may be formed. In this case, the gap formed between at least one of the three or more elastic pieces and the inner wall of the knock component 1 is at least a part of the guide path R40 (for example, a lead-out portion of the guide path R40, or a lead-out portion of the guide path R40, or A portion in the vicinity thereof) can be formed. Then, when the guide component 2 is relatively moved in the axial direction of the knock component 1, the size of the gap is changed by elastically deforming the tips of the plurality of extension pieces in the direction in which they are separated from each other. Can be made to.

On the contrary, the guide component 2 may include only one elastic piece. That is, in the above embodiment, the second elastic piece 26 may be omitted.

In the above embodiment, when the guide component 2 is moved forward relative to the knock component 1, both of the two elastic pieces 25 and 26 are elastically deformed in a direction in which the tips are separated from each other. However, the second elastic piece 26 does not necessarily have to undergo such elastic deformation, and only the tip of the first elastic piece 25 may be elastically deformed outward in the radial direction.

In the above embodiment, the size of the gap G is changed according to the operation of moving the guide part 2 relative to the knock part 1 back and forth, but the size of the gap G is changed. The mode of operation is not limited to this, and for example, the size of the gap G may be changed according to the operation of a lever or a button.

In the above embodiment, it is assumed that the unit parts 40 include three or more parts that are separate from each other, and the three or more parts are arranged with a gap provided so that at least a part of the guide path R40 is formed by the gap. It may be formed.

In the above embodiment, the unit component 40 forms a guide path R40 for guiding the writing core D filled in the core tank 20, but the unit component is similar to this and is the first of the delivery mechanism 30. 2 Guideway R301 may be formed.

In the above embodiment, the lead-out portion (or a portion in the vicinity thereof) of the guide path R40 is formed by the gap G provided between the knock component 1 and the guide component 2, but the guide path R40 The intermediate portion may be formed by a gap G provided between the knock component 1 and the guide component 2.

Further, the specific shape, specifications, and other detailed configurations of each part can be variously modified without departing from the spirit of the present invention. Needless to say, the embodiments and the configurations according to each modification may be appropriately combined.

P Mechanical pencil 10 Outer cylinder 20 Core tank 30 Delivery mechanism 40 Unit parts 1 Knock parts 13 Through window 14 Convex part 15 1st guide protrusion 15a Top surface 15c Inclined surface 16 2nd guide protrusion 16b Inclined surface 16c Top surface 17 Opposing protrusion 17a Top surface 17b Wall surface 2 Guide part 24 Slit 25 First elastic piece (extending piece)
251 Protrusion 251a Top surface of protrusion 251b Inclined surface of protrusion 251c Wall surface of protrusion 252 Sliding surface 26 Second elastic piece (extending piece)
261 Stepped part 261a Wall surface 261b Vertical wall surface 262 Sliding surface 27 Locking protrusion R40 Guideway G Gap

Claims (7)

Unit parts that form a guide path to guide the writing core,
With
In the unit parts
At least a portion of the guideway is formed by the gaps of a plurality of parts that are separate from each other and are arranged with a gap.
It is possible to switch between a state in which the gap is smaller than the diameter of the writing core and a state in which the gap is larger than the diameter of the writing core.
A mechanical pencil that features that. The mechanical pencil according to claim 1.
The plurality of parts are two parts.
A mechanical pencil that features that. The mechanical pencil according to claim 1 or 2.
The unit component is attached to the rear end of a core tank for accommodating a writing core, and is configured so that the writing core that has passed through the gap is filled in the core tank.
A mechanical pencil that features that. The mechanical pencil according to any one of claims 1 to 3.
The first part, which is one of the plurality of parts, is a tubular part.
A second component, which is another one of the plurality of components, is arranged inside the cylinder of the first component.
The gap is formed by a part of the inner wall surface of the first part and a part of the second part.
A mechanical pencil that features that. The mechanical pencil according to claim 4.
The second part is
An elastic piece arranged with the gap between it and the inner wall surface of the first component.
With
The size of the gap changes due to elastic deformation of the elastic piece.
A mechanical pencil that features that. The mechanical pencil according to claim 5.
The elastic piece is configured to be elastically deformed by the relative movement of the second component in the axial direction of the first component.
A mechanical pencil that features that. The mechanical pencil according to claim 6.
The second part is a tubular part, and a plurality of slits extending in the axial direction are arranged at the end thereof in the circumferential direction, whereby a plurality of extending pieces are formed at the end. ,
By moving the second component relative to the axial direction of the first component, the tips of the plurality of extension pieces are elastically deformed in a direction in which they are separated from each other.
At least one of the plurality of extension pieces forms the elastic piece.
A mechanical pencil that features that.

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