JPH0442151Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to a lead delivery mechanism for a sharp pencil in which an elastic body for chuck tightening is engaged with the lead chuck to facilitate assembly work.

[Conventional technology]

Heretofore, as this type of sharpening pencil, there has been one shown in FIG. 5, for example.

In the figure, the tip of the core pipe 101 includes a lead chuck 102, a chuck tightening ring 103, a sleeve 104, and a spring 10 for buffering excessive pen pressure.
5. A core delivery mechanism 107 consisting of a spring 106 for chuck tightening is fitted. Here, the assembly of the core delivery mechanism 107 to the core pipe 101 is as follows:
After inserting the chuck tightening ring 103, sleeve 104, and chuck tightening spring 106 from the rear end of the lead chuck 102, the core pipe 101
This is done by fitting the lead chuck 102 to the tip of the lead chuck.
Therefore, the tip of the core pipe 101 is pushed backward by the biasing force of the chuck tightening spring 106, making this fitting operation difficult and
It is necessary to press the spring 106 with fingers or a jig (not shown), which poses problems such as lower assembly efficiency.

[Summary of the idea]

This idea was made to solve the above problems, and by engaging a specially shaped elastic body for chuck tightening with the lead chuck, the lead delivery mechanism can be integrated into one piece. It is an object of the present invention to provide a lead delivery mechanism for a sharp pencil that can dramatically improve the efficiency of assembly work such as assembly to a lead pipe by combining the parts and making them handleable as one block.

〔Example〕

An embodiment of this invention will be described below with reference to the drawings.

As shown in FIG. 1, a core pipe 2 that is slidable in the axial direction is disposed within the outer cylinder 1, and a core delivery mechanism 3 is attached to the tip of the core pipe 2.

The lead delivery mechanism 3 includes a lead chuck 4 for mandrel fitting fitted to the tip of the core pipe 2, a chuck tightening ring 5 fitted externally in the axial direction on the head of the lead chuck 4, and a chuck tightening ring 5 fitted to the head of the lead chuck 4 in the axial direction. A cushion sleeve 6 that restricts the movement of the ring 5 in the axial direction and has a cushion portion 6a for cushioning excessive writing pressure.
and an elastic body 7 for chuck tightening that is attached between the cushion sleeve 6 and the tip of the core pipe 2.
and has.

Here, the lead chuck 4 has a rear end stepped portion 4 that bites into the inner wall of the core pipe 2 when the lead chuck 4 is fitted with the core pipe 2.
a, and an intermediate step portion 4b that comes into contact with the tip of the core pipe 2.
and has. The rear step portion 4a is for more securely fitting the lead chuck 4 into the core pipe 2, and can be omitted if necessary.

Further, as shown in the second figure, the elastic body 7 is formed into a substantially drum-like shape having a small-diameter body portion 7a having the smallest diameter at the center. The small-diameter body portion 7a is formed to have a smaller diameter than either the stepped portion 4a or 4b of the lead chuck 4, and is locked to the small-diameter body portion 4a or 4b before the core pipe 2 is attached (hereinafter referred to as a free state). (In this embodiment, the small-diameter body portion 7a of the elastic body 7 is locked to the intermediate stage portion 4b of the lead chuck 4.) Therefore,
In the lead feeding mechanism 3, in the free state, as shown in the third figure, the small diameter body 7a of the elastic body 7 is locked to either the stepped portion 4a or 4b of the lead chuck 4, so that it can be handled as a flock. It's summery.

Next, the operation of this invention will be explained.

To assemble the lead feeding mechanism 3, the chuck tightening ring 5, sleeve 6, and elastic body 7 are sequentially inserted from the rear end of the lead chuck 4, and the small diameter body 7a of the elastic body 7 is engaged with the stepped portion 4b of the lead chuck 4. make it stop In this state, the core delivery mechanism 3 is integrally connected by the elastic force of the elastic body 7 that is elastically attached between the sleeve 6 and the stepped portion 4b, and can be handled as one block. .

Therefore, when attaching the core delivery mechanism 3 to the core pipe 2, there is no need to press the elastic body 7 with fingers or a jig as in the conventional method, and the assembly can be easily performed, dramatically improving assembly efficiency. Here, in the process of fitting the lead chuck 4 to the tip of the core pipe 2, the rear end of the elastic body 7 is pressed by the tip of the core pipe 2 and moves forward against its own elastic force. The lead chuck 4 is inserted for a sufficient length into the tip of the core pipe 2, and is firmly fitted as shown in the fourth figure.

Incidentally, in the above embodiment, the small diameter body portion 7a of the elastic body 7
is locked to the middle step portion 4b of the lead chuck 4, but the present invention is not limited to this, and the rear end step portion 4a
Alternatively, it may be locked to a large-diameter locking part other than the stepped part.

Further, in this embodiment, a cushion sleeve is used as the sleeve 6, but it may be a normal sleeve, and it does not matter whether or not there is an elastic body for a cushion at the rear end of the sleeve 6.

〔effect〕

As described above, according to this invention, the small-diameter barrel of the approximately drum-shaped elastic body for chuck tightening is locked with the locking part of the lead chuck, so that the lead delivery mechanism is integrally connected, so to speak. It can be handled as one block, and has extremely excellent effects such as being able to efficiently perform assembly work such as assembling the core pipe.

[Brief explanation of drawings]

Fig. 1 is a vertical sectional view of the main part of a sharpening pencil to which an embodiment of this invention is applied, Fig. 2 is a plan view of an elastic body for tightening the chuck, and Fig. 3 is a free state of an embodiment of this invention. FIG. 4 is a longitudinal sectional view of one embodiment of this invention when the core pipe is fitted, and FIG.
The figure shows a longitudinal cross-sectional view of a conventional sharpening pencil. 4... Lead chuck, 4a, 4b... Locking part (stepped part), 5... Chuck tightening ring, 6... Sleeve, 7... Elastic body for chuck tightening, 7a...
Small diameter trunk.

Claims (1)

[Scope of utility model registration request] A lead chuck 4 for attaching the lead chuck, a sleeve 6 that abuts the chuck tightening ring 5 loosely fitted to the head of the lead chuck 4, and a small diameter body 7a disposed between the sleeve 6 and the lead chuck 4. and a roughly drum-shaped chuck tightening elastic body 7 which is locked to a locking part of the lead chuck 4.