JPH045347Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to an opening/closing device for a lead cartridge of a cassette type mechanical pencil.

[Conventional technology]

Recently, for example, the so-called cassette type cartridge, which stores writing leads as shown in Figure 7, has been replaced, eliminating the need to refill each lead individually and allowing the replacement and refilling of writing leads without getting your hands dirty. A mechanical pencil is suggested.

The lead cartridge 101 of a conventional cassette-type sharp pencil only has a cap 102 fitted on the tip. When replacing or replenishing the lead of a mechanical pencil, first remove the tip cap 102 and discard it, then replace the lead cartridge. It was fitted into the outer cylinder 103 of the sharp pencil with the tip open.

Therefore, if the lead cartridge 101 is turned downward even slightly after the tip cap 102 is removed, there is a problem in that the lead 104 will pop out from inside the lead cartridge 101.

Therefore, when replacing the core, it is necessary to always hold the core cartridge 101 upward while carefully fitting it into the outer cylinder 103.

Further, when removing the lead cartridge 101 from the outer cylinder 103, there was a problem that if the lead cartridge 101 was turned downward even slightly, it would fly out from inside the lead cartridge 101 and remain in the outer cylinder 103.

On the other hand, in the conventional one, as shown in FIG. 8, a lead cartridge 101 storing a large number of leads 104,
A lead guide 105 into which this lead cartridge 102 is removably inserted is housed in the outer cylinder 103. In order to pick up the remaining lead in the outer cylinder 103 with the lead card cartridge 101, a tapered inner surface is formed on the inner surface of the tip. The chamfered portion 107 is necessary, and the outer cylinder 1
As shown in the figure, it is necessary to provide an inner stepped wall 106 with a stepped shape, and this inner stepped wall 106 restricts the lead cartridge 101 to a small diameter, reducing the lead storage capacity. There was a problem. In addition, the inner stepped wall portion 106 as described above
Since the outer cylinder 103 having a shape cannot be extruded,
Injection molding must be performed, and in this case there was a problem that the mold was more expensive than extrusion molding.

This idea was made to solve the above problem.The lead passage hole opens only when the writing instrument is engaged with the writing instrument for replacing or replenishing the lead, and closes when it is not engaged. To provide an opening/closing device for a lead cartridge, which prevents the lead from popping out when replacing the lead cartridge, eliminates waste parts, enables extrusion molding of a writing instrument outer cylinder, and increases the lead storage capacity of the lead cartridge. With the goal.

[Means for solving problems]

The core cartridge opening/closing device according to this invention is
A chuck-type opening/closing mechanism, which is divided into multiple parts in the radial direction and has an inward elastic force and is provided on the lead cartridge, opens the lead conduction hole when the lead cartridge is elastically engaged with the lead guide, and closes when it is not engaged. An outward engaging piece is provided.

[Effect]

In the lead cartridge opening/closing device of this invention, the lead conduction hole opens when the outward engaging piece of the chuck type opening/closing mechanism snaps into engagement with the lead guide.
Closes when not engaged.

Of course, if the lead is held in the lead chuck and protrudes from the lead guide, it goes without saying that the lead opens the lead passage hole even before the lead is elastically engaged with the lead guide.

〔Example〕

An embodiment of this invention will be described below based on the drawings.

First, in FIG. 1, 1 is the outer barrel of the sharpening pencil, 2 is the tip screwed onto the tip of the outer barrel 1, and 3 is the outer barrel of the sharpening pencil.
is a part of the lead delivery mechanism disposed inside the outer cylinder 1, and has a lead chuck 5 for biting the lead 4, and a lead guide 6 is fitted to the rear end of the lead chuck 5. . Here, it is of course possible to add a chuck joint between the lead chuck 5 and the lead guide 6 to the design.

The lead guide 6 has a function of sending out the leads 4 one by one to the lead chuck 5, and has a front fitting hole 60 into which the rear end of the lead chuck 5 is fitted, as shown in FIGS. 2 and 3. A core feeding hole 61 with an inner diameter that is connected to this front side fitting hole 60 and can feed only one core 4, and a large diameter chuck storage hole 62 that is connected to the rear end of this core feeding hole 61 and has a stepped shape.
A large-diameter step-shaped rear fitting hole 63 is connected to the rear end and into which the core cartridge 7 is removably fitted.
and coaxially. Note that this rear fitting hole 6
A large number of holes (not shown) are bored in the peripheral wall of 3 for smooth attachment and detachment from the core cartridge 7.

A lead cartridge 7 is removably fitted into the lead guide 6 via an opening/closing mechanism 8.

The opening/closing mechanism 8 of the first embodiment has a rear cylinder portion 8 whose rear side is fitted into the tip opening of the core cartridge 7.
0, and a fourth portion provided at the tip of this rear cylinder portion 80.
It has elastic opening/closing pieces 81, 82, and 83 that are divided into a plurality of diametrically divided parts, such as three parts as shown in the figure and two parts as shown in the fifth figure.

These elastic opening/closing pieces 81, 82, 83 have inward elastic force and are expandable/contractable in the diametrical direction, and the cores 4 having different core diameters are electrically connected to their axial center portions. Core conduction hole 84 with an inner diameter that can be
is formed.

That is, when used only for leads 4 having the same core diameter, the lead conduction hole 84 is connected to the chuck storage hole 62 of the lead guide 6 by the outwardly engaging pieces 81a, 82a, 83a.
When engaged, the size is such that only one type of core 4, such as 0.5 mm, 0.7 mm, or 0.9 mm, can be electrically conductive. Next, the core 4 of different diameter (for example, 0.5mm and
0.7mm core),
The core conduction hole 84 is formed to have an opening size that allows conduction to any of the cores 4 when engaged with the lead guide 6, and is deformable to an opening size that does not allow conduction to any of the cores 4 when the engagement is released. has been done.

An inner wall tapered portion 85 is provided on the distal end side of the core through hole 84 .

And each elastic opening/closing piece part 81, 82, 83
are integrally formed with outward engaging pieces 81a, 82a, and 83a, respectively, which extend obliquely rearward in the axial direction and extend longer than the inner diameter of the chuck storage hole 62 of the lead guide 6.

The elastic opening/closing pieces 81, 82, 83 are press-fitted into the chuck storage hole 62, and the outward engaging pieces 81a, 82a, 83a are elastically engaged with the inner circumferential surface of the chuck storage hole 62. When they are not elastically engaged, the elastic opening/closing pieces 81, 82, 83 and the core through hole 84 are closed by the inward elastic force.

Therefore, from this state, the elastic opening/closing pieces 81, 82, 83 are inserted into the chuck storage hole 62 of the lead guide 6.
Insert the outward engaging pieces 81a, 82a, 83a.
When these outward engaging pieces 81 are elastically engaged,
When a, 82a, and 83a are deformed in the diameter-reducing direction, the elastic opening/closing pieces 81, 82, and 83 are elastically deformed in the diameter-expanding direction, and the core through hole 84 is opened.

Next, the operation will be explained.

To replace the lead or to check the lead midway, the lead cartridge 7 fitted into the lead guide 6 is removed together with the opening/closing mechanism 8. At the time of this removal, the core conduction hole 84 is automatically closed to a diameter of 0.5 mm or less, for example, to which the core 4 cannot conduct. Therefore, when the lead cartridge 7 is pulled out, there is no risk that the lead 4 in the lead cartridge 7 will come off through the opening at its tip and remain in the outer cylinder 1 or spill out of the outer cylinder 1.

Furthermore, since there is no risk of residual core generation, there is no need to provide a chamfered part such as a taper on the inner surface of the tip of the core cartridge 7, so there is no need to provide a chamfered portion such as a taper on the inner surface of the tip when molding the core cartridge 7. There are no manufacturing problems. Furthermore, unlike in the past, it is no longer necessary to provide an inner stepped wall inside the outer cylinder 1, so the outer cylinder 1 can also be formed by inexpensive extrusion molding, and the diameter of the core cartridge 7 can also be reduced. It can be made thicker and the amount of core storage can be increased dramatically. In addition, the lead feed hole 61 of the lead guide 6 and the opening mechanism 8
If the core 4 remains across the core conduction hole 84 of
When the elastic engagement is released, the elastic opening/closing pieces 81, 82, 83
is elastically deformed in the diametrical direction, and is chucked by the elastic opening/closing pieces 81, 82, 83 and pulled out. Therefore, after removing the lead cartridge 7, if the lead 4 is pulled out from the lead passage hole 84 or pushed into the lead cartridge 7, the remaining lead 4 can be removed when the lead cartridge 7 is replaced. There is no risk of breakage or lead guide 6 clogging due to the broken core 4.

Then, when a new core cartridge 7 is pushed in from the rear end of the outer cylinder 1, the outward engaging piece 8 of the opening/closing mechanism 8
1a, 82a, and 83a are press-fitted into the rear inner cylindrical portion 61 of the lead guide 6 and are snap-fitted, whereby,
The lead passage hole 84 of the opening/closing mechanism 8 is opened as described above, and the lead 4 can be supplied. When replacing the core cartridge 7, the outward engaging piece 81
Since the lead conduction hole 84 is closed until the leads a, 82a, and 83a are inserted into the chuck storage hole 62, there is no risk that the lead 4 in the lead cartridge 7 will pop out as in the conventional case. In addition, there is no need to hold the sharp pencil upside down and keep the lead cartridge 7 facing upward while replacing the pencil.
To perform the replacement work of a lead cartridge 7 extremely simply and easily regardless of the direction of the sharp pencil.

In particular, in the opening/closing mechanism 8, the plurality of elastic opening/closing pieces 81, 82, 83 each have an outward engaging piece 81.
a, 82a, 83a, and can be opened and closed in the radial direction via these outwardly engaging pieces 81a, 82a, 83a, so that it is possible to store cores 4 of the same diameter or different core diameters. The new lead cartridge 7 can be attached to the lead guide 6 in the manner described above to enable supply of the new lead 4.

That is, the opening/closing mechanism 8 has the outward engaging piece portion 81
a, 82a, 83a, the elastic opening/closing piece 81,
Since the opening/closing degree of the opening/closing operations of 82 and 83 is adjusted, the cores 4 of different diameters as well as cores of the same diameter can be used.

FIG. 6 is a sectional view of the opening/closing mechanism 8 according to the second embodiment.

In this embodiment, inside the chuck storage hole 62 of the lead guide 6, the rear end side gradually becomes smaller in diameter, and the outer diameter of the smaller diameter end is the elastic opening/closing piece part 81, 82, 83.
A tapered cylindrical portion 64 having a slightly smaller diameter than the natural opening diameter is provided. When the lead cartridge 7 is inserted into the outer cylinder 1, the tapered cylindrical part 64 has an outward engaging piece 8 on the inner peripheral surface of the chuck storage hole 62 of the lead guide 6.
1a, 82a, 83a are elastically engaged and the tapered end portions of the elastic opening/closing pieces 81, 82, 83, which are deformed to open, are press-fitted, thereby opening the outward engaging pieces 81a, 82a, 83a. will be carried out even more smoothly. In addition, as a result, the core conduction hole 8
4 can be opened even more reliably.

[Effect of idea]

As described above, according to this invention, the chuck type opening/closing mechanism, which is divided into a plurality of parts in the radial direction and has an inward elastic force and is provided on the lead cartridge, is provided with a lead conduction mechanism when the lead cartridge is elastically engaged with the lead guide. Open the hole,
By providing an outward engaging piece that closes when not engaged, the lead conduction hole opens when the outward engaging piece snaps into engagement with the lead guide, and closes when not engaged. There is no risk of the lead popping out when replacing the writing instrument, and the chuck-type opening/closing mechanism closes when replacing the lead cartridge, allowing the remaining lead from the writing instrument to be removed, thereby preventing the remaining lead from breaking. There is no possibility that the broken lead will cause the writing instrument to become clogged, and the lead cartridge can be replaced very simply and easily.

In particular, the opening/closing mechanism allows the core cartridge to share not only cores of the same diameter but also cores of different diameters, and eliminates the need for discarded parts such as caps of conventional core cartridges.
Moreover, since there is no need to provide a thick stepped wall portion of the outer cylinder, it is possible to extrude the writing instrument outer cylinder, and many excellent effects can be obtained, such as increasing the lead storage capacity of the lead cartridge.

[Brief explanation of drawings]

Fig. 1 is a schematic perspective view of a cassette-type sharp pencil according to an embodiment of this invention, Fig. 2 is a sectional view of the lead cartridge attachment part of the same mechanical pencil before assembly, and Fig. 3 shows the same after assembly. 4 and 5 are front views of each opening/closing mechanism in the same essential parts, FIG. 6 is a sectional view of the opening/closing mechanism according to the second embodiment, and FIG. 7 is a perspective view of a conventional core cartridge. , FIG. 8 is a longitudinal sectional view of a conventional sharpening pencil of this type. 4 is a lead, 6 is a lead guide, 7 is a lead cartridge, 8 is a chuck type opening/closing mechanism, 81a, 82a,
83a is an outward engaging piece portion, and 84 is a core through hole.

Claims (1)

[Scope of utility model registration request] Lead 4 is removably fitted to the sharp pencil.
a lead cartridge 7 for replenishing and replacing the lead cartridge; a chuck-type opening/closing mechanism 8 that is divided into a plurality of parts in the radial direction and having an inward elastic force and is provided on the lead cartridge 7; The outward engaging piece 8 opens the core conduction hole 84 when the lead guide 6 is engaged with the lead guide 6, and closes it when the lead guide 6 is not engaged.
1a, 82a, and 83a.