JP2019081387A - Writing instrument - Google Patents

Abstract

To provide a writing instrument capable of preventing a lead from breaking at writing time with no need of any attentions paid to a writing angle or a writing pressure.SOLUTION: A writing instrument comprises: a lead delivery mechanism 4 disposed in a barrel 2, the lead delivery mechanism 4 configured to deliver a lead 11 inside the barrel 2 through a tip 3d of a front opening 3 disposed on a front side of the barrel 2 when operated; and an elastic deformation part 16 disposed on a rear side of the front opening 3, including a front end part 16a continuously connected with a latter part 3c of the front opening 3 and a rear end part 16b engaged with a connection part 12 disposed inside the barrel 2. In addition, an expansive part 16d, which can expand outward, is formed in the elastic deformation part 16.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a writing instrument. More specifically, the present invention relates to a writing tool having a core feeding mechanism disposed in a shaft cylinder and operating the core feeding mechanism to feed the core in the shaft cylinder from the tip of a tip of a tip provided in front of the shaft cylinder. .

DESCRIPTION OF RELATED ART Conventionally, the writing instrument provided with the core delivery mechanism which draws out the cores for writing, such as a pencil, a color pencil, and a crayon, is known. When writing using a writing instrument provided with this lead-out mechanism, it is necessary to cause the lead to protrude from the end of the writing tool by operating the lead-out mechanism, but the amount of protrusion of the lead is When it becomes long, the protruding part may be broken, and a structure for preventing core breakage is regarded as important.
The core-break preventing structure is a structure that is particularly required in a sharp pencil that draws out a thin, flexible, and easily broken core among writing instruments.

As a structure of a mechanical pencil which prevents core breakage, there is known a technique for preventing core breakage by a pen pressure buffer means when a certain pressure or more is applied to the core at the time of writing. For example, Patent Document 1 describes a mechanical pencil that contracts a buffer spring to retract a core when an excessive pen pressure is applied to the core to prevent core breakage.
In the mechanical pencil described in Patent Document 1, a buffer spring is fitted to a core pipe fixed to the rear of a chuck that holds the core, and an excessive writing pressure in the axial direction with respect to the core and the chuck When it is applied, the buffer spring contracts to retract the chuck and the core. Therefore, when writing with the mechanical pencil standing upright to the writing surface, the writing pressure is transmitted to the buffer spring through the core as it is, but when writing with the mechanical pencil inclined to the writing surface, the writing is applied to the core As for the writing pressure, the force applied in the axial direction of the core decreases and the force acting in the axial direction increases. Therefore, when writing with the mechanical pencil inclined to the writing surface, the core may not be able to withstand the writing pressure and may be broken without contraction of the buffer spring, and the core may not be broken. It was necessary to write while paying attention to the writing angle of the mechanical pencil.

As a configuration other than the patent document 1, in the patent document 2, when an excessive writing pressure is applied to the core at the time of writing, the writing unit including the base and the core feeding mechanism tilts to the fulcrum in the shaft main body. Mechanical pencils that prevent core breakage are described.
In the mechanical pencil described in Patent Document 2, core bending can be prevented by tilting the writing unit even when writing is performed while being inclined to the writing surface, but the writing pressure is further increased from the tilted state of the writing unit There is a possibility that the core may be broken due to load on the core, and it was necessary to write while paying attention to the writing pressure.

Japanese Utility Model Publication No. 56-130874 JP, 2010-264638, A

  An object of the present invention is to provide a writing instrument capable of preventing a core breakage without paying attention to a writing angle and a writing pressure at the time of writing, in view of the above-mentioned problems.

The present invention
1. A writing tool having a structure in which a core feeding mechanism is disposed in a shaft cylinder and the core feeding mechanism is operated to feed the core in the shaft cylinder from the tip of the tip of the tip provided in front of the shaft cylinder. A resilient member has a front end connected to a rear part of the front opening and a rear end connected to a connecting part provided inward of the barrel or a front part of the lead-out mechanism. A deformation portion is provided, and a bulging portion that bulges outward is formed in the elastic deformation portion, and when a pressure is applied to the core, the bulging portion of the elastic deformation portion is pressed against the inner surface of the shaft cylinder By elastically deforming, the distance between the front end portion and the rear end portion of the elastic deformation portion extends in the direction along the axial center, and the front end connected to the elastic deformation portion is forward with respect to the core feeding mechanism. And the front end of the core is protected by the tip of the tip.
2. A locking portion projecting inward is formed on the inner surface of the barrel, and the locking portion of the barrel and the locked portion provided on the outer surface of the connecting portion are locked to lock the barrel. The writing instrument as set forth in the above item 1, wherein the connecting member is configured to be capable of tilting in a direction perpendicular to the axis centering on the support portion.
3. The writing instrument according to any one of the above items 1 or 2, wherein a guide portion in which a side surface is in sliding contact with the inner surface of the tip is provided in front of the core feeding mechanism.
4. The writing instrument according to any one of the above items 1 to 3, wherein at least a part of the bulging portion of the elastically deformable portion is always in contact with the inner surface of the barrel.
5. The writing instrument according to any one of the above items 1 to 4, wherein the bulging portion of the elastically deformable portion comprises a plurality of flexible pieces.
6. The resilient member is disposed between the front portion of the connecting member and the stepped portion provided in the lead-out mechanism, and the lead-out mechanism is resiliently pushed forward by the resilient member. The writing instrument as described in any one of -5. ".

The writing instrument of the present invention can be used for a writing instrument that can draw out a writing core such as a pencil, a colored pencil, or a crayon, and can be suitably used for a sharp pencil that draws a thin, flexible and fragile core.
As the core feeding mechanism in the mechanical pencil, a known mechanical pencil core feeding structure can be used, and the operation method may be a rear end knocking type in which the core is fed out by knocking on the back of the core feeding mechanism. The delivery mechanism may be a side knock type in which the core is drawn by knocking from the side.
The elastic deformation portion may be formed integrally with the front end in the rear portion of the front end, and integrally with the connection portion or the core delivery mechanism in the front portion of the connection portion or in the front portion of the core delivery mechanism. It may be formed, and the tip and the connecting part or the core feeding mechanism and the elastically deforming part may be formed separately and connected to each other.

The shape of the bulging portion formed between the front end portion and the rear end portion of the elastically deforming portion is a thin portion that is bent to form a bulging portion with metal or hard resin that can obtain elasticity, and itself Differs in the case where the bulging portion is formed of elastic rubber or foamed resin.
When the bulging portion is formed of metal or hard resin, the cross-sectional shape is formed such that the front and the rear gradually expand relative to each other from the point of contact with the inner surface of the shaft cylinder, for example, the outer side narrows. A triangular shape, a trapezoidal shape, an arc shape, etc. can be adopted. Needless to say, the base is not provided when forming in a triangular shape or a trapezoidal shape so that the bulging part can be deformed, and when forming in a circular shape, no chord is provided, and in front of the bulging part It is necessary to make the rear freely spread in the direction along the axis.
When forming a bulging portion with rubber or foamed resin, the cross-sectional shape is formed into a triangular shape, a trapezoidal shape, or an arc shape filled with rubber or foamed resin, and the inside is tapered. The entire bulging portion is pressure-welded from the contact point to the inner surface as a base point, and it is necessary to make the front and the rear of the bulging portion extend in the direction along the axial center by collapsing inward.

The connecting portion in the present invention is provided between the shaft cylinder and the core feeding mechanism, and the core feeding mechanism is disposed at the axial center of the shaft cylinder, and a part of the core feeding mechanism is provided in the hole formed in the connecting portion. By inserting it, the center of the core feeding mechanism and the center of the shaft cylinder are aligned.
The connecting portion can be formed integrally or separately from the barrel, but at least a part of the connecting portion does not move relative to the barrel in order to arrange the core feeding mechanism at the axial center of the barrel. It is important to

The locking means between the locking portion provided on the shaft cylinder and the locked portion provided on the connecting portion may be fitted by press fitting the locking portion and the locked portion, and the locking portion and the locked portion A screw may be formed on the locking portion and screwed, and the locked portion of the connecting member may be abutted on the locking portion of the barrel so that the connecting member can not move forward relative to the barrel May be locked.
Further, as a method of tilting the connecting portion, the connecting portion is formed of a soft material such as a synthetic resin, and the connecting portion is configured to be tilted by bending, or the connecting portion is formed of a hard material such as metal. It may be configured to be locked so that the whole of the connecting portion can be tilted with the locking portion of as shown in FIG.
Furthermore, the length from the fulcrum to the tip of the connecting portion can be increased by forming the locking portion of the barrel serving as the fulcrum behind the central portion in the axial direction of the barrel. By doing so, it is preferable because it is easy to tilt when the connecting portion is bent with respect to the fulcrum or when the entire connecting portion is tilted.

Further, by continuously arranging a guide portion in sliding contact with the inner surface of the front end in the front of the core feeding mechanism, the elastic deformation portion elastically deforms at the time of writing to move the front end forward. By moving along the side surface of the guide portion, the front end does not become unstable, and the axial center of the front end and the axial center of the guide portion can be maintained in alignment, so that the front end is not loaded on the core. It can slide.
The guide portion may be formed integrally with the core feeding mechanism or may be formed separately, but if a core breakage occurs between the tip and the core feeding mechanism, the broken core can be removed As described above, it is preferable that the core feeding mechanism and the guide portion be separately formed, and that the guide member and the core feeding mechanism or the connecting portion including the core feeding mechanism be detachably attachable by screwing or the like.

  In addition, at least a part of the bulging portion of the elastically deforming portion is always in contact with the inner surface of the shaft cylinder, so that when the writing pressure is applied to the core, the bulging portion of the elastically deforming portion is elastically deformed The pen can support the core together with the tip, and when an excessive load is applied to the core, the bulging portion immediately starts elastic deformation and pushes the tip forward, so the tip is broken before the core is broken. The tip of the mouth can protect the core.

Furthermore, the bulging portion of the elastically deformable portion is constituted by a plurality of flexible pieces having the same shape and having the same shape, and the flexible piece is formed in a bowl shape or arc shape which bulges outward. Thus, when a pressure is applied to the core, the flexible piece is pressed against the inner surface of the barrel and elastically deformed so as to extend in the axial direction, thereby increasing the distance between the front end portion and the rear end portion of the elastically deformable portion. be able to.
In addition, when a plurality of flexible pieces are uniformly disposed on the outer periphery of the bulging portion, when writing pressure is applied to the core, a plurality of positions may be grasped and written in the circumferential direction of the writing instrument One of the flexible pieces is pressed against the inner surface of the shaft cylinder to start elastic deformation, and the other adjacent flexible pieces successively start elastic deformation, and the entire flexible piece extends along the axial center. The mouth can be moved forward, and core breakage can be prevented regardless of the position at which the writing instrument is held.

A resilient member is disposed between the front portion of the connecting member and the stepped portion provided in the lead-out mechanism, and the lead-out mechanism is resiliently urged forward by the resilient member, whereby the writing instrument is against the writing surface When writing is performed so as to be close to the vertical axis, when the writing pressure increases, the elastic member contracts and the core feeding mechanism retracts, the core is protected by the tip of the front opening, and the core is broken It can be prevented.
Here, when writing with the writing tool standing vertically, writing pressure applied to the core is applied almost all to the axial direction of the core, and the force applied to the axial diameter direction of the core becomes extremely small, so only the buffer spring acts Thus, the core and the core feeding mechanism can be retracted to protect the core at the tip of the tip.
Also, as the writing angle of the writing instrument is inclined, the force applied in the axial direction of the core decreases, and the force acting in the axial diameter direction of the core increases accordingly, so the connecting portion and the core feeding mechanism By tilting, the bulging portion of the elastically deforming portion is pressed against the inner surface of the barrel and elastically deformed, and the front opening moves forward to protect the core with the front end of the front opening. Therefore, as the writing tool is inclined to the writing surface, the writing pressure is more easily transmitted to the elastic deformation portion, and as the writing tool is closer to the writing surface, the writing pressure is easily transmitted to the buffer spring.

  In the present invention, when writing is performed with the writing tool inclined relative to the writing surface, the core can be protected by moving the tip to the front even if excessive writing pressure is applied to the core. It has become possible to provide a writing instrument capable of preventing core breakage without paying attention to pressure.

It is a side view of the mechanical pencil of a present Example. It is a longitudinal end view of FIG. It is the longitudinal end view which expanded the principal part. FIG. 4 is an end view taken along line A-A of FIG. FIG. 5A is an end view showing the normal state of the elastic deformation member, and FIG. 5B is an end view showing a state in which the elastic deformation member is stretched. It is the principal part end view which showed the state which inclines 60 degrees of writing angles of the mechanical pencil of FIG. 1 with respect to a writing surface, and writes. FIG. 7 is an end view of an essential part showing a state in which the tip is moved forward by applying an excessive writing pressure to the core in the writing state of FIG. 6; It is the principal part end elevation view which showed the state which stood up perpendicularly | vertically with respect to the writing surface, and writes in the mechanical pencil of FIG. FIG. 9 is an end view of an essential part showing a state in which an excessive writing pressure is applied to the core in the writing state of FIG. 8 and the core and the core feeding mechanism are retracted;

Hereinafter, the writing instrument of a present Example is demonstrated based on FIGS. 1-9. In order to make the description easy to understand, similar members in the drawings and similar portions are denoted by the same reference numerals. In the description of this embodiment, a pencil will be used as a writing instrument, and the side with the tip of the mechanical pencil will be expressed as the front, and the opposite side will be expressed as the rear.
In addition, in the mechanical pencil in a present Example, in the state before writing, it comprises in the state to which the axial center of the axial cylinder and the axial center of components other than axial cylinder corresponded.

  As shown in FIG. 1, a mechanical pencil 1 which is a writing instrument of this embodiment has a front end 3 in front of a barrel 2 and incorporates a core feeding mechanism behind the front end 3 and in the barrel 2 The core 11 pinched by the core feeding mechanism is made to project from the tip 3 d of the tip 3, and the knock member 5 inserted from the rear into the barrel 2 is mounted, and the knock member 5 is pressed forward. The core 11 is configured to be fed forward.

  Next, each configuration of the mechanical pencil 1 of the present embodiment will be described using FIGS. 2 and 3. More specifically, the chuck 7 having a plurality of divided front portions is inserted into the tip end hole 6 a of the cylindrical member 6 having a through hole penetrating in the front and back direction, and the clamp 8 is inserted into the head 7 a of the chuck 7. Then, the pipe-like core tank 9 is press-fitted and fixed to the rear of the chuck 7. In addition, a chuck spring 10 with an attachment load of about 400 g is attached between the inner flange 6b of the cylindrical member 6 and the front end of the core tank 9, and the chuck 7, the clamp 8, the cylindrical member 6, the core tank 9 and the chuck The spring 10 and the core 10 constitute a core feeding mechanism 4 for feeding the core 11.

  The centering mechanism 4 is inserted from the tip inner hole 12a of the connecting member 12 extending in the axial direction and having a through hole at the center, and the stepped portion 6d of the outer collar 6c provided on the cylindrical member 6 and the connecting member 12 A buffer spring 13 with a mounting load of about 350 g is attached as a resilient member between the step 12b of the tip inner hole, and the core feeding mechanism 4 is resiliently forward with respect to the step 12b of the tip inner hole of the connecting member 12. It has been released. In addition, a guide member 14 having a stepped through-hole is disposed in front of the connection member 12, and a female screw portion 14 a provided at the rear of the guide member 14 and a first one provided at the front of the connection member 12. The screw is detachably screwed on the male screw portion 12c. At this time, the outer ring 6c of the cylindrical member 6 abuts on the rear part 14b of the guide member 14, and the forward movement of the lead-out mechanism 4 is blocked. Further, the fastener 8 is loosely fitted between the front end 6e of the cylindrical member 6 and the inner step 14c of the guide member 14 so as to be movable in the longitudinal direction.

Furthermore, the connecting member 12 is inserted from the front inner hole 2a of the barrel 2 described above, and the stepped engaging portion 2c provided on the rear inner surface 2b of the barrel 2 receives the engaged portion 12d of the rear of the linking member 12 It is fixed by press fitting. Further, the core tank 9 is formed to project rearward from the rear end of the connecting member 12, and the knock member 5 described above is detachably mounted to the rear of the core tank 9.
In the present embodiment, the core tank 9 of the connecting member 12 and the core feeding mechanism 4 is formed of a synthetic resin which is a soft material, so that the core tank 9 of the core feeding mechanism 4 contained in the connecting member 12 and the connecting member 12. Is bent, and the connecting member 12 and the core feeding mechanism 4 are configured to tilt with the locking portion 2c as a fulcrum.

  The front end 3 described above is disposed in front of the guide member 14, and the front outer peripheral portion 14 d of the guide member 14 is inserted into the sliding portion 3 a provided in the inner hole of the front end 3. It is configured to be slidable in a direction along the axis of 14. Further, a core holding member 15 for holding the core 11 with a force of about 10 g is built in the front step portion 3 b of the inner hole of the front port 3. Furthermore, an elastic deformation member 16 connecting the front opening 3 and the connection member 12 is disposed between the front opening 3 and the connection member 12, and the front end portion 16a formed in a tubular shape at the front of the elastic deformation member 16 is a front opening While being press fitted and fixed to the rear part 3c of 3, the cylindrical rear end 16b is formed at the rear of the elastic deformation member 16, and the female screw 16c provided on the inner surface of the rear end 16b is provided on the outer periphery of the connecting member 12. The second male screw portion 12e is detachably screwed and connected.

As shown in FIGS. 4 and 5A, the elastic deformation member 16 is configured by eight flexible pieces 16e which bulge the bulged part 16d outward, and the eight flexible pieces 16e are bulged parts. It is uniformly disposed on the outer periphery of 16 d. In addition, the flexible piece 16e is formed in a bowl shape that bulges the top 16f outward, and the top 16f of the flexible piece 16e is configured to abut on the front inner surface 2d of the barrel 2. Furthermore, a concave groove 16g is formed in the top 16f, and when the top 16f of the flexible piece 16e abuts on the front inner surface 2d of the barrel 2, the top 16f is thinner than the straight portion 16h by the groove 16g. As shown in FIG. 5B, the flexible piece 16e is elastically deformed so as to extend in the axial direction with the straight portion 16h maintained with the apex 16f as a base point, and the front end 16a of the elastic deformation member 16 The rear end portions 16 b move away from each other.
In the present embodiment, the elastically deformable member 16 is formed by pressing using a metal material so that elastic deformation starts when a force of about 300 g is applied to the flexible piece 16e.
When the elastic deformation member 16 is inserted into the barrel 2, the top 16f of the flexible piece 16e abuts on the front inner surface 2d of the barrel 2 and is attached in a slightly deformed state. As a result, even if the dimensions of the barrel 2 and the elastic deformation member 16 vary, the flexible piece 16e and the front inner surface 2d of the barrel 2 can be brought into contact with each other. The axial center of the tip 3 fixed to the member 16 and the elastic deformation member 16 is guided to a state of being in agreement

Next, the situation where the lead 11 is drawn out by the mechanical pencil 1 of the present embodiment will be described with reference to FIG. FIG. 2 is a longitudinal cross-sectional view showing a state in which the core 11 is fed out from the tip 3d of the front opening 3. When writing is performed and the core 11 is worn in the core feeding state of FIG. By performing a knock operation to press forward, the chuck 7 and the fastener 8 move forward together with the core tank 9, and the core 11 is drawn out by the distance the fastener 8 has advanced. Thereafter, the clamp 8 abuts against the bore step 14c of the guide member 14 and the forward movement of the clamp 8 stops, and the head 7a of the chuck 7 separates from the clamp 8 and expands. The head 7a of 7 abuts on the core holding member 15, and the advancing of the chuck 7 is stopped.
When the pressure on the knock member 5 is released, the chuck 7 is retracted by the extension of the chuck spring 10, the head 7a of the chuck 7 is pressed by the fastener 8, the chuck 7 is closed, and the core 11 is held again. The state in which the core 11 of FIG. 2 is fed out from the front end 3 is maintained to enable writing.

Next, the case where the mechanical pencil 1 of the present embodiment is written at an angle of 60 ° with respect to the writing surface 100 will be described using FIGS. 6 and 7.
As shown in FIG. 6, when writing is performed by inclining the mechanical pencil 1 by 60 ° with respect to the writing surface 100, the axial center and tip 3 of the barrel 2 gripped under normal writing pressure (about 200 g to 300 g) When the writing pressure exceeding 300 g is applied to the core 11, the connecting member 12 and the locking portion 2c (see FIG. 2) of the barrel 2 are used as a fulcrum. As the core feeding mechanism 4 bends, the tip 3 tilts so as to approach the front inner surface 2d. Furthermore, since the top 16f of the flexible piece 16e of the elastically deformable member 16 is pressed against the front inner surface 2d of the barrel 2, the flexible piece 16e linearly extends from the bowl shape in the direction along the axial center. It elastically deforms and the distance between the front end 16a and the rear end 16b of the elastic deformation member 16 increases. At this time, the rear end portion 16 b of the elastically deformable portion 16 is screwed to the connecting member 12, and the connecting member 12 is press-fitted and fixed to the shaft cylinder 2, so that the shaft cylinder 2 held by the user is gripped The connecting member 12 does not move, and the front opening 3 moves forward along the front outer peripheral portion 14d of the guide member 14 together with the front end 16a of the elastic deformation member 16, as shown in FIG. The core 11 during writing is protected by the tip 3d of the mouth 3, and the core 11 can be prevented from being broken.
When the pressure applied to the core 11 is released from the state shown in FIG. 7, the flexible piece 16e extending linearly by elastic deformation returns to the original hook-like shape, and hence the front opening fixed to the elastic deformation member 16 3 is also retracted to expose the core 11, and the axis centers of the connecting member 12 and the core feeding mechanism 4 which has been tilted move so as to coincide with the axis center of the barrel 2, and return to the state of FIG.
In the mechanical pencil 1 of this embodiment, as the writing angle is inclined, the force in the axial direction with respect to the core decreases, and the force acting in the axial radial direction of the core increases. Therefore, the pen pressure applied to the core 11 is easily transmitted to the elastic deformation member 16 through the tip 3 as the mechanical pencil 1 is inclined, and the elastic deformation member 16 is elastically deformed so as to extend in the axial center direction of the core 11 It becomes easy to move tip 3 to the front.

Next, the case where the mechanical pencil 1 of the present embodiment is written vertically (90 °) with respect to the writing surface 100 will be described using FIG. 8 and FIG. 9 as shown in FIG. When writing while standing upright on the writing surface 100 without tilting the pen, the writing pressure applied to the core 11 is almost the same as that of the elastic deformation member 16 as when writing with the mechanical pencil 1 tilted. Since it does not propagate, the front end 3 does not advance. Therefore, when a pen pressure of 350 g or more is applied to the core 11, the force is transmitted to the core feeding mechanism 4 holding the core 11, and the buffer spring 13 resiliently contracting the core feeding mechanism 4 contracts. The core feeding mechanism 4 retreats. At this time, the middle step 3e of the front end 3 abuts on the front end 14e of the guide member 14 and does not retreat, and as shown in FIG. 9, only the core 11 and the core feeding mechanism 4 with respect to the front end 3 The core 11 is protected by the tip 3 d of the tip 3 by retreating.
When the writing pressure applied to the core 11 is released from the state of FIG. 9, the core 11 and the core feeding mechanism 4 move forward by extension of the buffer spring 13, and the core 11 protrudes from the tip 3d of the tip 3 and the state of FIG. Return to At this time, the front end 3 holding the core 11 by the core holding member 15 together with the core 11 also tries to move forward, but the core holding force of the core holding member 15 is set weak at about 10 g. The flexible piece 16e can not be deformed and the tip 3 does not move forward.

Further, even when writing with the mechanical pencil 1 tilted, since the writing pressure is transmitted to the core feeding mechanism 4 via the core 11, the core spring 11 contracts so that the core 11 and the core 11 are held by the core feeding mechanism. The force applied in the axial direction of the core 11 is reduced among the writing pressure applied to the core 11 as the mechanical pencil 1 is inclined but the load on the buffer spring 13 is reduced. A higher writing pressure is required. This becomes larger as the writing angle is inclined, and conversely, it becomes closer to the mounting weight (350 g) as the writing angle approaches perpendicular.
That is, the relationship between the buffer spring 13 and the elastic deformation member 16 in this embodiment is that the buffer spring 13 is more easily contracted as the writing angle approaches perpendicular, and the core 11 is retracted to protect the core 11 and the writing angle is The force is more easily transmitted to the elastic deformation member 16 as it is inclined, and the flexible piece 16 e of the elastic deformation member 16 is extended to advance the tip 3 and protect the core 11.
Therefore, it has become possible to provide a writing instrument capable of writing without paying attention to the writing angle even when writing with high writing pressure.

  The structure of the writing instrument according to the present invention can be used not only for mechanical pencils, but also for colored pencils having a feeding mechanism of rod-like materials, and writing instruments having a mechanism for delivering a writable core such as crayon and chalk.

1 ... Mechanical pencil,
Reference Signs List 2 shaft tube 2a front inner hole 2b rear inner surface 2c locking portion 2d front inner surface
3: tip opening 3a: sliding portion 3b: leading step portion 3c: rear end portion 3d: leading end portion 3e: middle step portion 4: core feeding mechanism,
5 ... knocking member,
6 ... cylindrical member, 6a ... tip end opening, 6b ... inner ring, 6c ... outer ring, 6d ... step portion, 6e ... front end portion,
7 ... Chuck, 7a ... head,
8 ... fasteners,
9 ... core tank,
10 ... Chuck spring,
11 ... core,
12 ... connection member, 12a ... tip inner hole, 12b ... stepped portion, 12c ... first male screw portion,
12d: locked portion 12e: second male screw portion
13 ... Buffer spring,
14 guide member 14a female screw portion 14b rear stage portion 14c inner hole step portion
14d: front outer periphery, 14e: tip,
15: Core holding member,
16: elastic deformation member, 16a: front end portion, 16b: rear end portion, 16c: female screw portion,
16d: bulging portion, 16e: flexible piece, 16f: top portion, 16g: groove portion, 16h: linear portion,
100 ... writing surface.

The present invention
1. A writing tool having a structure in which a core feeding mechanism is disposed in a shaft cylinder and the core feeding mechanism is operated to feed the core in the shaft cylinder from the tip of the tip of the tip provided in front of the shaft cylinder. ,
A bulging portion which bulges outward is formed at the rear of the tip, and the bulging portion is such that the front end is connected to the rear of the tip and the rear end is inside the barrel. It is front portion and continuously provided in the connecting portion or the core feeding mechanism is provided for those,
When writing pressure is applied to the core, the bulging portion is brought into pressure contact with the inner surface of the shaft cylinder, whereby the tip moves forward with respect to the core feeding mechanism, and the front end portion of the core is the tip A writing instrument characterized in that a tip portion of a mouth is protected and a guide portion for advancing the tip end along an axial direction is provided in front of the core feeding mechanism .
2. The guide portion is disposed behind the tip opening, and when the writing pressure is applied to the core, the tip opening is brought into sliding contact with the outer peripheral portion of the guide portion to move forward. Writing instruments described in Section.
3. A locking portion projecting inward is formed on the inner surface of the barrel, and the locking portion of the barrel and the locked portion provided on the outer surface of the connecting portion are locked to lock the barrel. The writing instrument according to any one of the above items 1 or 2, wherein the connecting member is configured to be tiltable in a direction perpendicular to the axis centering on the support portion.
4. The writing instrument according to any one of the above items 1 to 3, wherein at least a part of the bulging portion is always in contact with the inner surface of the barrel.
5. The writing instrument according to any one of the above items 1 to 4, wherein the bulging portion is provided with an elastic deformation portion having elasticity .
6. The resilient member is disposed between the front portion of the connecting member and the stepped portion provided in the lead-out mechanism, and the lead-out mechanism is resiliently pushed forward by the resilient member. The writing instrument as described in any one of -5. ".

Claims (6)

  A writing tool having a structure in which a core feeding mechanism is disposed in a shaft cylinder and the core feeding mechanism is operated to feed the core in the shaft cylinder from the tip of a tip of the tip provided in front of the shaft cylinder. At the rear of the mouth, the front end part is connected to the rear part of the front opening, and the rear end is a connecting part provided on the inner side of the cylinder or an elastic deformation part connected to the front part of the core feeding mechanism. The bulging portion bulging outward is formed in the elastic deformation portion, and when a pressure is applied to the core, the bulging portion of the elastic deformation portion is brought into pressure contact with the inner surface of the barrel and elastically deforms. As a result, the distance between the front end portion and the rear end portion of the elastically deformable portion spreads in the direction along the axial center, and the tip of the elastically deformable portion continuously moved forward with respect to the core feeding mechanism. A writing instrument characterized in that the front end of the core is protected by the front end of the front end   A locking portion projecting inward is formed on the inner surface of the barrel, and the locking portion of the barrel and the locked portion provided on the outer surface of the connecting portion are locked to lock the barrel. The writing instrument according to claim 1, wherein the connecting member is configured to be capable of tilting in a direction perpendicular to the axis centering on the support portion.   The writing instrument according to claim 1 or 2, wherein a guide portion which is in sliding contact with the inner surface of the tip opening is connected to the front of the core feeding mechanism.   The writing instrument according to any one of claims 1 to 3, wherein at least a part of the bulging portion of the elastically deformable portion is always in contact with the inner surface of the barrel.   The writing instrument according to any one of claims 1 to 4, wherein the bulging portion of the elastically deformable portion comprises a plurality of flexible pieces.   A resilient member is disposed between the front portion of the connecting member and the step portion provided in the core feeding mechanism, and the core feeding mechanism is resiliently forwardly moved by the resilient member. The writing instrument according to any one of claims 1 to 5.

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