JP6824019B2 - mechanical pencil - Google Patents

Description

The present invention relates to a mechanical pencil capable of writing by pulling out a predetermined amount of a writing core from the tip of a mouthpiece by a knock operation or the like.

Conventionally, there has been a problem that if a high writing pressure is applied to the writing core when writing with a mechanical pencil, the writing core exposed from the tip of the base is easily broken. As for the breakage of the writing core, if the writing pressure is constant, the smaller the angle between the axial direction of the mechanical pencil shaft and the paper surface (the more the shaft is laid down), or the more the writing core is exposed from the tip of the base. The longer the length of, the more remarkable it is.

In response to such a problem, Patent Document 1 (Japanese Patent Laid-Open No. 2015-123689) states that when a high writing pressure is applied to the writing core, the axial component of the writing pressure and the writing pressure are perpendicular to the axial direction. A mechanical pencil is described in which the components are absorbed by different mechanisms to reduce the breakage of the writing core.

Specifically, in the mechanical pencil of Patent Document 1, the base is supported by the shaft cylinder via an elastic body (spring), and the base is a cam slope whose diameter gradually decreases toward the rear in the axial direction of the shaft cylinder. have. Further, the shaft cylinder is formed with a pressing portion that presses the cam slope forward in the axial direction of the shaft cylinder. With such a configuration, the cam slope of the base is pressed forward by the pressing portion in the axial direction of the axial cylinder due to the writing pressure component (force in the outer diameter of the axial cylinder) in the direction orthogonal to the axial direction of the axial cylinder. Then, the base slides forward (jumps out) from the tip of the barrel. As a result, the length of the writing core exposed from the tip of the base is reduced.
Further, in the mechanical pencil of Patent Document 1, the lead feeding unit for feeding the writing core is urged forward in the axial direction (the front end direction of the base in the axial direction) by an elastic body (spring), and the mechanical pencil is in the axial direction of the shaft cylinder. It is supported by the barrel in a state of being relatively movable. Then, the core feeding unit including the writing core moves relative to the rear in the axial direction of the barrel, so that the component in the axial direction of the writing pressure is absorbed. As a result, the length of the writing core exposed from the tip of the mouthpiece is further reduced, and the breakage of the writing core is reduced.

In the mechanical pencil described in Patent Document 1, when a high writing pressure is applied to the writing core, the base is suddenly moved over the maximum length (stroke) at which the base can slide forward with respect to the barrel. It is designed to slide (jump out).

On the other hand, in the present inventor, when a high writing pressure is applied to the writing core, the base slides with respect to the shaft cylinder in the radial direction of the shaft cylinder, and the writing core is rearward with respect to the base. We developed a structure that slides in and filed it as an international application PCT / JP2016 / 068863. In such a mechanical pencil, breakage of the writing core can be effectively avoided, but in order to further improve the degree of perfection, it has been required to provide a better writing feeling.

JP-A-2015-123689

As a result of diligent studies, the inventor of the present invention has found that improving the slidability of the base that slides with respect to many other members is effective in improving the writing feeling.

The present invention is based on the above findings, and an object of the present invention is to reliably avoid breakage of the writing core when a high writing pressure is applied to the writing core, and to further smooth the writing feeling. To provide a mechanical pencil.

The present invention
"1. Shaft tube and
A core feeding unit for feeding the writing core, in which the rear region is supported in the barrel so that the front region can be flexed and deformed or tilted in the barrel.
An overhanging portion provided on the outer peripheral surface of the front region of the core feeding unit, and
A protruding portion provided on the inner peripheral surface axially rearward of the overhanging portion of the barrel,
A stretchable elastic body arranged in a compressed state between the overhanging portion and the protruding portion,
With
It is further provided with a base that is arranged in the tip region of the core feeding unit and is movable relative to the core feeding unit in the axial direction of the axle.
The core feeding unit has a core feeding unit main body whose front end is surrounded by the mouthpiece, and a holding member for holding the base in the core feeding unit main body in a retaining state.
The core feeding unit has a pressed portion on the holding member.
The barrel has a pressing portion in the front region and has a pressing portion.
At least one of the pressed portion and the pressed portion is a tapered surface whose diameter gradually increases toward the rear in the axial direction.
The base is
A tubular front region that projects axially forward from the front end of the barrel and surrounds the writing core that is fed from the core feeding unit.
A step portion of the front region, which is provided at the rear of the axle in the axial direction and extends outward in the radial direction of the axle.
Have,
The shaft cylinder has an inner collar protruding inward in the radial direction of the shaft cylinder in front of the step portion in the axial direction of the shaft cylinder.
The step portion and the inner collar come into contact with each other,
Before the front region of the lead feeding unit bends, deforms, or tilts in the barrel, the pressed portion and the pressed portion are in contact with each other, and the front region of the lead feeding unit is inside the barrel. In a mechanical pencil in which the pressed portion moves the pressed portion relative to the axially rearward with respect to the barrel when the mechanical pencil is deformed or tilted.
A mechanical pencil characterized in that the base has a lubricating plating layer containing a fluororesin in a metal plating on the surface.
2. 2. The mechanical pencil according to item 1, wherein the tin-cobalt-plated layer is provided on the surface of the base by exposing a part of the lubricating-plated layer. ".

According to the present invention, when a high writing pressure is applied to the writing core, the front region of the core feeding unit is bent and deformable or tilted in the shaft cylinder by a component perpendicular to the axial direction of the writing pressure. As a result, the core feeding unit including the writing core is moved relative to the axle in the axial direction against the urging force of the elastic body, so that the length of the writing core exposed from the tip of the base is reduced. To. Further, due to the axial component of the writing pressure, the core feeding unit including the writing core is further moved axially backward with respect to the barrel against the urging force of the elastic body, and the writing is exposed from the tip of the mouthpiece. The length of the wick is further reduced. As a result, breakage of the writing core is avoided when a high writing pressure is applied to the writing core. Further, at this time, the core feeding unit including the writing core is not moved (jumped out) axially forward with respect to the shaft cylinder, but is moved relative to the axially rearward with respect to the base. The length of the writing core exposed from the mouthpiece is reduced. This makes it possible to provide a mechanical pencil with a smooth writing feeling.

In the present invention, since the surface of the base is provided with a lubricating plating layer containing fluororesin in the metal plating, the frictional force can be reduced by rubbing against each member or the paper surface in contact with the base, resulting in a result. It is possible to provide a mechanical pencil in which the base or a member in contact with the base operates smoothly to make the writing feeling smoother.
Further, by providing the lubricating plating layer on the tip of the mouthpiece, the frictional resistance of the writing core at the tip of the mouthpiece is reduced, and as a result, the side surface of the writing core is scraped by rubbing against the tip of the mouthpiece. Can be prevented.

Furthermore, by providing a tin cobalt plating layer on the surface of the base by exposing a part of the lubricating plating layer, darkening due to the lubricating plating layer containing fluororesin in the metal plating is reduced, and a glossy feeling peculiar to metal is obtained. It can be maintained, and since a part of the lubricating plating layer is exposed, slidability can also be maintained.

It should be noted that preferably, the pressed portion of the core feeding unit is the tapered surface, and the tapered surface has any angle between 20 ° and 60 ° with respect to the axial direction of the barrel. The elastic body is a coil spring, and the load required to move the pressed portion relative to the axle in the axial direction against the urging force of the coil spring is 0.5 N to Any value between 8N.

In this case, when a high writing pressure is applied to the writing core, the core feeding unit including the writing core can be reliably moved rearward in the axial direction with respect to the barrel, so that the writing core is prevented from being broken. On the other hand, when an appropriate writing pressure is applied to the writing core, the core feeding unit including the writing core is not substantially moved rearward in the axial direction with respect to the barrel, so that the writing quality is not impaired.

According to the present invention, it is possible to avoid breakage of the writing core when a high writing pressure is applied to the writing core, and it is possible to provide a mechanical pencil having a smooth writing feeling.

It is a schematic vertical sectional view of the mechanical pencil of embodiment of this invention. It is a schematic vertical sectional view of the front area of the mechanical pencil of FIG. 1 when the writing pressure is not applied to the writing core. It is a schematic vertical sectional view of the front area of the mechanical pencil of FIG. 1 when the writing pressure is applied to the writing core. It is a perspective view which shows the state which disassembled the internal part in the mechanical pencil of FIG. It is a perspective view which shows the state which the internal part in the mechanical pencil of FIG. 1 was assembled. The cross section of the base is schematically shown, FIG. 6A is a diagram showing a state after plating, and FIG. 6B is a diagram showing a state in which holes are exposed on the inner surface of the base after plating.

FIG. 1 is a schematic vertical sectional view of the mechanical pencil 100 according to the first embodiment of the present invention, and FIG. 2 shows the mechanical pencil 100 of FIG. 1 when no pressure is applied to the writing core 70. FIG. 3 is a schematic vertical cross-sectional view of the front region, and FIG. 3 is a schematic vertical cross-sectional view of the front region of the mechanical pencil 100 of FIG. 1 when a writing pressure is applied to the writing core 70.

As shown in FIGS. 1 to 3, the mechanical pencil 100 of the present embodiment has a writing core 70 which is supported in the shaft cylinder 10 and the shaft cylinder 10 and whose front region can be tilted in the shaft cylinder 10. A lead feeding unit 40 for feeding is provided. The axle cylinder 10 of the present embodiment is made of transparent polycarbonate and is composed of a rear shaft 20 and a front shaft 30 whose rear region is fixed (screwed) to the front region of the rear shaft 20.

The core feeding unit 40 of the present embodiment is fixed to a polypropylene core pipe 41 extending in the axial direction of the shaft cylinder 10 inside the shaft cylinder 10 and to the front end portion of the core pipe 41 via a connector 49. A brass chuck 43, a brass tightening ring 42 fitted in the front region of the chuck 43, an outer cylinder 45 surrounding the chuck 43, and a core pipe 41 attached to the rear of the outer cylinder 45 in the axial direction. It has a return spring 44 and a force.

Specifically, as shown in FIGS. 2 and 3, the outer cylinder 45 has a flange 45c (overhanging portion) that supports the chuck 43 on the inner peripheral surface of the front region and overhangs the outer peripheral surface of the rear region. It has a rear cylinder 45a and a front cylinder 45b that is screwed into the front end region of the rear cylinder 45a and extends axially forward beyond the front end portion of the chuck 43. Further, the rear cylinder 45a has an inner collar 45d at the front end portion, and a return spring 44 is arranged in a compressed state between the inner collar 45d and the connector 49, and the core is arranged with respect to the outer cylinder 45. The pipe 41 is urged rearward in the axial direction. In this state, the chuck 43 is fastened by the tightening ring 42 and holds the writing core 70 so as not to retract.

Further, the shaft cylinder 10 (rear shaft 20) has a protruding portion 21 on the inner peripheral surface axially rearward of the flange 45c of the outer cylinder 45, and expands and contracts between the protruding portion 21 and the flange 45c. A possible coil spring 60 is arranged in a compressed state. With such a configuration, the core feeding unit 40 including the writing core 70 can move rearward in the axial direction with respect to the axle cylinder 10 against the urging force of the coil spring 60.

Further, the inner diameter of the rear region of the front shaft 30 is larger than the outer diameter of the flange portion 45c, and a gap is formed between the inner peripheral surface of the front shaft 30 and the outer peripheral surface of the flange portion 45c. As a result, the center feeding unit 40 is allowed to tilt with respect to the barrel 10.

Further, a brass base 52 is attached to the tip region of the core feeding unit 40. The base 52 of the present embodiment is arranged in the tip region of the core feeding unit 40, and can move relative to the core feeding unit 40 in the axial direction of the shaft cylinder 10. As shown in FIGS. 2 and 3, the base 52 is composed of a tubular front region 52a that guides the writing core 70 and a sleeve-shaped rear region 52b having a diameter larger than that of the front region 52a. .. The rear region 52b has a front small diameter portion 52c and a rear diameter expansion portion 52d, and the small diameter portion 52c and the diameter expansion portion 52d are connected by a shoulder portion 52e.
The mouthpiece 52 of the core feeding unit main body 40a is in a state of being prevented from coming off by the front cylinder 45b and the tubular holding member 40b in which the front cylinder 45b is internally fitted and fixed, and in a state of being slidable in the axial direction of the shaft cylinder 10. Attached to the tip area. Specifically, as shown in FIGS. 2 and 3, the holding member 40b includes a tubular main body 40c surrounding the rear region 52b of the base 52 and a stopper 40d formed in the rear end region of the main body 40c. ,have.
The inner surface of the main body 40c has a reduced diameter portion 40e whose inner diameter is smaller than other regions of the main body 40c. A flat surface 45e facing forward in the axial direction is formed on the outer surface of the outer cylinder 45 axially behind the reduced diameter portion 40e, and can be expanded and contracted between the shoulder portion 52e and the flat surface 45e of the base 52. A spring 55 in a compressed state is arranged.
With such a configuration, the base 52 is slidably held inside the holding member 40b in the axial direction of the main body 40c, and undesired detachment from the main body 40c is prevented. Further, the front end of the main body portion 40c is an opening, and the front region 52a of the mouthpiece 52 projects forward from this opening.

The holding member 40b has a pressed portion 53 at the front end portion. The pressed portion 53 of the present embodiment is configured as a tapered surface having an angle of 40 ° with respect to the axial direction of the barrel 10. Further, the axle cylinder 10 (front axle 30) has a pressing portion 32 protruding from the inner peripheral surface in the front region. In the present embodiment, as shown in FIG. 2, the pressing portion 32 and the pressed portion 53 are in contact with each other before the core feeding unit 40 is tilted. Then, as shown in FIG. 3, when the core feeding unit 40 is tilted, the pressing portion 32 moves the pressed portion 53 relative to the axle cylinder 10 in the axial direction rearward. In the present embodiment, the spring constant of the coil spring 60 is 1600 N / m, and the pressed portion 53 (tapered surface) is relatively moved rearward in the axial direction with respect to the axle cylinder 10 against the urging force of the coil spring 60. The load required for this is 5.0 N. Further, the spring constant of the coil spring 55 is 1000 N / m, and by setting the urging force of the coil spring 55 to be smaller than the urging force of the coil spring 60, the outer cylinder 45 shown in FIG. 2 is moved from a stationary state to the outside shown in FIG. The contact state between the base 52 and the inner flange 33 of the shaft cylinder 10 is maintained until the cylinder 45 starts to move.

Further, as shown in FIG. 1, the core feeding unit 40 is attached to the rear end of the core pipe 41 and further has a knock portion 48 for pressing the core pipe 41 forward in the axial direction with respect to the outer cylinder 45. doing. The knock portion 48 of the present embodiment has a sleeve portion 48a that is externally fitted to the rear end region of the core pipe 41 in the front in the axial direction, and a columnar eraser 80 can be removed in the rear in the axial direction. It has a holder portion 48b to hold. The internal space of the sleeve portion 48a and the internal space of the holder portion 48b are communicated with each other by an opening. As a result, by removing the eraser 80 from the holder portion 48b, the writing core 70 can be inserted into the core pipe 41 through the opening. Further, a dome-shaped knob 81 that covers the rear of the eraser 80 is detachably fitted to the holder portion 48b.

Further, in the present embodiment, the crown 23 is fixed to the rear end region of the rear shaft 20. A step portion 23a facing rearward in the axial direction is formed on the inner peripheral surface of the crown 23. Further, a flange portion 48c is formed on the outer periphery of the holder portion 48b, and a stretchable spring 48d is arranged in a compressed state between the flange portion 48c and the step portion 23a.

Next, the operation of the mechanical pencil 100 according to the embodiment of the present invention will be described.

First, prior to writing on the paper surface, if necessary, the knob 81 and the eraser 80 are removed from the holder portion 48b, and the writing core 70 passes through the opening that communicates the sleeve portion 48a and the holder portion 48b. It is put into the core pipe 41. Then, the eraser 80 and the knob 81 are attached to the holder portion 48b, and the knock portion 48 (knob 81) is pressed (knocked) in the axially forward direction with the front end of the mouthpiece 52 facing downward. As a result, the core pipe 41, the connector 49, the chuck 43, and the tightening ring 42 are advanced against the urging force of the return spring 44. In the middle of this advance, only the tightening ring 42 comes into contact with the contact step portion 45e formed on the front cylinder 45b of the outer cylinder 45. As a result, the tightening ring 42 is removed rearward from the chuck 43, the chuck 43 is opened, and the writing core 70 is extended. At the time of pressing (knocking), an appropriate resistance is provided by the urging force of the spring 48d arranged between the flange portion 48c of the knock portion 48 and the step portion 23a of the crown 23.

Then, when the pressed state of the knock portion 48 (knob 81) is released, the core pipe 41 is retracted together with the chuck 43 by the urging force of the return spring 44. Along with this, the tightening ring 42 is fitted again to the front region of the chuck 43, and the chuck 43 is tightened. As a result, the writing core 70 is sandwiched so as not to retract, and the state in which the writing core 70 is extended is maintained. Then, by appropriately repeating this series of pressing operations, the writing core 70 is exposed (delivered) to a desired length from the tip of the base 52 (see FIG. 2). Then, the front shaft 30 is gripped by the user, and the writing is performed by moving the shaft cylinder 10 as desired while bringing the writing core 70 into contact with the paper surface.

At the time of writing, the barrel 10 is generally gripped so that its axial direction makes an acute angle with respect to the paper surface (see FIGS. 2 and 3). Therefore, a writing pressure including a component perpendicular to the axial direction of the barrel 10 and a component in the axial direction is applied to the writing core 70. When a high writing pressure is applied to the writing core 70 during writing, the mechanical pencil 100 of the present embodiment absorbs a component perpendicular to the writing pressure and a component in the axial direction, respectively, from the tip of the base 52. Avoid breaking the exposed writing core 70.

Specifically, as shown in FIG. 3, the front region of the core feeding unit 40 is tilted by a component perpendicular to the axial direction of the writing pressure, and the pressed portion 53 of the front cylinder 45b is pressed by the pressing portion 32 of the front shaft 30. It is pressed backward in the axial direction of the barrel 10. As a result, the core feeding unit 40 including the writing core 70 is moved relative to the axle cylinder 10 in the axial direction rearward against the urging force of the coil spring 60. On the other hand, since the base 52 is urged forward in the axial direction with respect to the holding member 40b by the coil spring 55, the base 52 is not moved relative to the rear in the axial direction with respect to the barrel 10. As a result, the length of the writing core 70 exposed from the tip of the base 52 is reduced.

At the same time, the writing core 70 may be pressed axially backward with respect to the barrel 10 by the axial component of the writing pressure. As a result, the core feeding unit 40 including the writing core 70 is further moved rearward in the axial direction against the urging force of the coil spring 60. That is, the length of the writing core 70 exposed from the tip of the base 52 can be further reduced, and breakage of the writing core 70 can be avoided.

Then, when the writing pressure applied to the writing core 70 is weakened, the core feeding unit 40 including the writing core 70 is pushed back axially forward with respect to the barrel 10 by the urging force of the coil spring 60. As a result, the initial state (see FIG. 2) is restored.

According to the present embodiment as described above, when a high writing pressure is applied to the writing core 70, the front region of the core feeding unit 40 is tilted in the shaft cylinder 10 by a component perpendicular to the axial direction of the writing pressure. To. As a result, the core feeding unit 40 including the writing core 70 is moved rearward in the axial direction with respect to the axle cylinder 10 against the urging force of the coil spring 60, so that the writing core 70 exposed from the tip of the base 52 The length is reduced. Further, due to the axial component of the writing pressure, the core feeding unit 40 including the writing core 70 is further moved axially rearward with respect to the barrel 10 against the urging force of the coil spring 60, and is further moved rearward in the axial direction from the tip of the base 52. The length of the exposed writing core 70 is further reduced. As a result, breakage of the writing core 70 is avoided when a high writing pressure is applied to the writing core 70. Further, at this time, the base 52 is not moved (jumped out) axially forward with respect to the shaft cylinder 10, but the core feeding unit 40 including the writing core 70 is relatively moved backward with respect to the base 52. By doing so, the length of the writing core 70 exposed from the base 52 is reduced. Therefore, when the tip of the base 52 comes into contact with the paper surface, the length of the writing core 70 exposed from the base 52 is quickly increased by the urging force of the coil spring 60 by slightly reducing the writing pressure. Therefore, the catch between the tip end portion 52f of the base 52 and the paper surface can be quickly eliminated.

Further, in the base 52 of the present embodiment, the inner flange 33 of the shaft cylinder 10, the holding member 40b, the front cylinder 45b, or the front cylinder 45b, which the base 52 is in contact with, is provided by providing a lubricating plating layer containing fluororesin in the metal plating on the surface. The slidability with the spring 55 is improved, and as shown in FIG. 3, the center feeding unit 40 moves smoothly when the front region of the core feeding unit 40 is tilted by the component perpendicular to the axial direction of the writing pressure, and the writing feeling becomes smoother. Become.

Further, by providing the tin cobalt plating layer on the surface of the base 52 by exposing a part of the lubricating plating layer, darkening due to the lubricating plating layer containing fluororesin in the metal plating is reduced, and a glossy feeling peculiar to metal is reduced. In addition, since a part of the lubricating plating layer is exposed, slidability can also be maintained.

Next, the plating layer of the base will be described in detail with reference to FIG.
FIG. 6 schematically shows a cross section of the base, FIG. 6A shows a state after plating, and FIG. 6B is a view showing a state in which holes are removed from the inner surface of the base after plating.
In the plating layer 90 in this example, fluororesin-containing plating manufactured by Tsuneki Plating Industry Co., Ltd. was used.
Further, in the base 52 of this example, the lubricating plating layer 91 was applied at about 5 μm, and then the tin cobalt plating layer 92 was applied at about 0.3 μm. The volume concentration of the lubricating plating layer 91 is 20 to 24%.
As a result, in the plating layer 90, the tin cobalt plating layer 92 is widely present on the surface of the base 52, and the lubricating plating layers 91 are scattered on the surface of the base 52.
In the mouthpiece 52 of this embodiment, a through hole 52 g through which the writing core is inserted is preformed with a 0.58 mm drill to match the 0.5 mm writing core, and then a plating layer is formed on the surface as shown in FIG. 6A. 90 is provided. After that, the base 52 shown in FIG. 6B was completed by drilling holes with a drill of 0.58 mm. The tip portion 52f is an inclined surface whose diameter gradually increases toward the tip.
As shown in FIG. 6B, the plating layer 90 remains on the surface of the through hole 52 g of the mouthpiece 52 that has been drilled. This is because the cutting marks due to the drilling deviate from the position when the through hole 52g is formed in the base 52 in advance. In addition, the plating layer 90 remains at the tip portion that is not cut by drilling holes. Therefore, the friction between the through hole 52g of the base 52 and the writing core is reduced, and smooth operation can be performed. Further, the friction between the tip portion 52f and the writing core is also reduced, and it is possible to prevent the side surface of the writing core from being scraped by the rubbing against the tip portion 52f of the base 52.
The base 52 of the present embodiment can obtain the glossiness peculiar to the metal due to the tin cobalt plating layer 92 while obtaining the slippery effect of the lubricating plating layer 91, whereby the portion exposed from the barrel 10 or a transparent portion can be obtained. It is possible to improve the design of the portion that can be seen through the barrel 10.

10 Axle 20 Rear shaft 21 Protruding part 23 Head crown 23a Step part 30 Front shaft 32 Pressing part 33 Inner flange 40 Core feeding unit 40a Core feeding unit main body 40b Holding member 40c Main body 40d Stopper 40e Reduced diameter part 41 Core pipe 42 Tightening Ring 43 Chuck 44 Return spring 45 Outer cylinder 45a Rear cylinder 45b Front cylinder 45c Flange 45d Inner collar 45e Contact step 45f Flat part 48 Knock part 48a Sleeve part 48b Holder part 48c Flange part 48d Spring 49 Connector 52 Base 52a Front area 52b Rear area 52c Small diameter part 52d Large diameter part 52e Shoulder part 52f Tip part 52g Through hole
52h Step 53 Pressed portion 55 Spring 60 Coil spring 70 Writing core 80 Eraser 81 Knob 90 Plating layer 91 Lubricating plating layer 92 Tin cobalt plating layer 100 Mechanical pencil

Claims (2)

Axial tube and
A core feeding unit for feeding the writing core, in which the rear region is supported in the barrel so that the front region can be flexed and deformed or tilted in the barrel.
An overhanging portion provided on the outer peripheral surface of the front region of the core feeding unit, and
A protruding portion provided on the inner peripheral surface axially rearward of the overhanging portion of the barrel,
A stretchable elastic body arranged in a compressed state between the overhanging portion and the protruding portion,
With
Further provided with a base that is arranged in the tip region of the core feeding unit and is movable relative to the core feeding unit in the axial direction of the shaft cylinder.
The core feeding unit has a core feeding unit main body whose front end is surrounded by the mouthpiece, and a holding member for holding the base in the core feeding unit main body in a retaining state.
The core feeding unit has a pressed portion on the holding member.
The barrel has a pressing portion in the front region and has a pressing portion.
At least one of the pressed portion and the pressed portion is a tapered surface whose diameter gradually increases toward the rear in the axial direction.
The base is
A tubular front region that projects axially forward from the front end of the barrel and surrounds the writing core that is fed from the core feeding unit.
A step portion of the front region, which is provided at the rear of the axle in the axial direction and extends outward in the radial direction of the axle.
Have,
The shaft cylinder has an inner collar protruding inward in the radial direction of the shaft cylinder in front of the step portion in the axial direction of the shaft cylinder.
The step portion and the inner collar come into contact with each other,
Before the front region of the lead feeding unit bends, deforms, or tilts in the barrel, the pressed portion and the pressed portion are in contact with each other, and the front region of the lead feeding unit is inside the barrel. In a mechanical pencil in which the pressed portion moves the pressed portion relative to the axially rearward with respect to the barrel when the mechanical pencil is deformed or tilted.
A mechanical pencil characterized in that the base has a lubricating plating layer containing a fluororesin in a metal plating on the surface. The mechanical pencil according to claim 1, wherein the tin-cobalt-plated layer is provided on the surface of the mouthpiece by exposing a part of the lubricating-plated layer.

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