JPH0517273Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to a sharpening pencil that prevents the lead from breaking and is provided with a mechanism to prevent the lead from breaking.

[Conventional technology]

In a conventional sharp pencil, for example, as shown in FIG. 13, a lead chuck 101 for inserting a lead is fixed to the tip of a lead pipe 102. Therefore,
When the rear end cap 104 is pulled out to use the eraser 103, or when the lead is inserted into the lead pipe 102.
When the eraser 103 is pulled out to replenish the eraser, the core pipe 102 and the lead chuck 101 fixed thereto are pulled backward.
There were problems in that the core attached in step 1 could break, and that the core would also rotate when the core pipe 102 rotated.

In particular, as shown in FIG. 14, the outer cylinder 105 is divided into a front end outer cylinder 105a and a rear end outer cylinder 105b,
Moreover, in the case of a sharpening pencil in which the rear end outer cylinder 105b is fitted to the core pipe 102, as the core pipe 102 rotates, the lead and the rear end outer cylinder 105b
Since the device also rotates, it is very inconvenient for the user to use, and there is also a problem in that the user feels uncomfortable.

The object of this invention is to provide a sharpening pencil that solves the above-mentioned problems.

[Means for solving problems]

In the sharp pencil according to this invention, the gap a between the inner diameter of the lead chuck and the outer diameter of the lead is greater than or equal to the distance b that allows the lead chuck to move in the diameter direction of the outer cylinder, and the inner diameter of the lead pipe or its accessories The gap c with the outer diameter of the core is formed to be equal to or larger than the distance d that is the movement distance of the core pipe or its accessory in the direction of the outer diameter.

[Effect]

The sharp pencil in this invention is
Even if you drop it, it will definitely prevent the core from breaking.

〔Example〕

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

As shown in the first diagram, the sharpening pencil of this invention has a core pipe 2 housed in an outer cylinder 1 so as to be slidable in the axial direction, and a core pipe 2 which is formed separately from the core pipe 2 and is also slidable in the axial direction. Lead chuck 3 wearing a core
and has.

A first joint (an accessory part of the core pipe 2) 4 is fitted and connected to the tip of the core pipe 2, and a second joint (an accessory part of the core pipe 2) is connected to the first joint 4. The rear end portions of 5 are connected, for example, by screwing or the like.

Further, in front of the core pipe 2, a first internal thread 7 and a second internal thread 8 are arranged coaxially.

More specifically, the first internal thread 7 has a distal end thereof screwed into the rear end side of the tip tool 6.
The inward flange at the tip of the outer cylinder 1 is sandwiched between the rear end and the rear end.

In this way, the second internal thread 8 is removably screwed into the rear end side of the first internal thread 7 whose tip is removably connected to the tip 6 and the outer cylinder 1. ing.

As shown in the first figure, a part of this second internal thread 8 engages with a rotation prevention protrusion (rotation prevention part) 2a formed protrudingly on a part of the core pipe 2, and the core pipe 2
A rotation prevention groove 8a is provided to prevent rotation.

Therefore, the core pipe 2 has the second internal thread 8.
It is connected in a non-rotating state and slidably in the axial direction.

A first elastic body 9 is elastically attached between the second joint 5 and the second internal thread 8.

This first elastic body 9 not only serves to prevent rattling, but also biases the second joint 5 toward the lead chuck 3, so that no gap is created between the second joint 5 and a third joint 10 described later.

Since the first elastic body 9 biases in the direction of releasing the chuck tightening, it is configured to have a weaker biasing force than the second elastic body 12 described later.

Next, regarding the lead chuck 3, its rear end is fixed by screwing or the like to a third joint 10 which is slidable on the inner wall of the first internal thread 7 which functions as a sleeve. Further, the top end of the lead chuck 3 is tightened by a chuck tightening tube 11.

A second elastic body 12 for chuck tightening is attached between the third joint 10 and the first internal thread 7. Reference numeral 13 in the figure is a rubber packing that applies frictional force to the core 14.

In the above description, the lead chuck 3, the chuck tightening tube 11, and the second elastic body 12 constitute the lead delivery mechanism A.

Here, the inner diameter of the lead chuck 3 and the core 14 are
The gap a between the lead chuck 3 and the outer diameter of the outer cylinder 1 is
The distance b that can be moved in the diameter direction of the outer cylinder (a≧
b).

In addition, the gap c between the inner diameter of the second joint 5, which is an accessory part of the core pipe 2, and the outer diameter of the core 14 is the distance d that the second joint 5 can move in the outer cylinder diametrical direction within the outer cylinder 1. or more (c≧d).

According to the above configuration, the core pipe 2
When the rear end of the lead chuck is knocked, the lead chuck 3 is pushed forward by the second joint 5, and the core is fed normally.

In this invention, since the lead chuck 3 and the core pipe 2 are formed separately, even if the eraser and the rear end cap (both not shown) attached to the rear end of the lead pipe 2 are pulled out, the lead chuck 3 and the core pipe 2 are formed separately. Since the pulling force does not act on the lead chuck 3 at all, breakage of the core 14 due to excessive biting force of the lead chuck 3 as in the conventional case is reliably prevented.
Furthermore, since the core pipe 2 and the core delivery mechanism A are constructed so that there is no gap, there is a problem that residual core, core waste, etc. may become clogged between them, making it impossible to deliver the core. There isn't.

Furthermore, since the core pipe 2 is prevented from rotating, even in the case of the sharp pencil shown in FIG. 14, the core pipe 2 is prevented from rotating and the rear end outer cylinder does not rotate.

Furthermore, in the event that the sharpening pencil is dropped and collides with the floor or the ground, an impact force will act on the lead delivery mechanism A and the lead 14.
Since the relationships a≧b and c≧d hold as described above, the maximum clearance (gap a) that allows the maximum deflection of the core 14 in the core delivery mechanism A is the
The maximum clearance (distance b) that allows the maximum movement in the diametrical direction of the outer cylinder, which is the direction of deflection of the third joint 10 within the second joint 5, and the maximum deflection of the core 14 within the second joint 5. The maximum allowable clearance (gap c) is greater than the maximum clearance (distance d) that allows the second joint 5 to move in the diametrical direction of the outer cylinder, which is the direction in which the second joint 5 bends. , core breakage is reliably prevented.

Moreover, since the first elastic body 9 is attached between the core pipe 2 and the core delivery mechanism A, it is possible to prevent looseness between the core pipe 2 and the lead delivery mechanism A, leading to breakage of the core and malfunction. Smoothness etc. is reliably prevented.

2 to 5, as in the above embodiment,
The rotation of the core pipe 2 is prevented by a washer (rotation prevention part) 15 fitted near the tip of the core pipe 2 instead of the rotation prevention protrusion 2a formed on the core pipe 2, and the first elastic body The rear end of 9 is locked to create a shape with no gap between the third joint 10 and the tip of the core pipe 2, and to prevent play in the core pipe 2.
This prevents the core from breaking, etc., and ensures smooth operation.

This washer 15 has a cut groove 15a formed therein as shown in FIG.
It is formed so that it can be reliably engaged with 6a.
Also, a rotation prevention groove 16a that engages with the washer 15
is formed in a sleeve 16 that functions as a sleeve and is fixed to the tip 6 and the outer cylinder 1.

Note that the interior of the washer 15 is formed with a polygonal shape or a protrusion so that it can be reliably fitted with the core pipe 2.

In this embodiment as well, the gap a between the inner diameter of the lead chuck 3 and the outer diameter of the core 14 is the distance b over which the lead chuck 3 can move in the outer cylinder diameter direction within the outer cylinder 1.
or more (a≧b).

Further, the gap c between the inner diameter of the core pipe 2 and the outer diameter of the core 14 is formed to be at least a distance d (c≧d) by which the core pipe 2 can move within the outer cylinder 1 in the outer cylinder diameter direction.

As described above, in this embodiment as well, the lead feeding mechanism A consisting of the lead chuck 3 and the like and the core pipe 2 are formed separately with no gap, and the Since one elastic body 9 is landed and the relationships a≧b and c≧d hold, the same effects as in the above embodiment can be obtained.

FIG. 6 shows an embodiment in which play a is formed between the tip of the core pipe 2 and the first internal thread 7 in order to prevent rattling and ensure smooth operation, and the same effect as the above-mentioned embodiment is achieved. play.

In the embodiments shown in FIGS. 7 to 10, a first elastic body 9 for preventing rattling is attached between the core pipe 2 and the first internal thread 7, and the same effect as described above is obtained. play.

1st embodiment of FIG. 11, FIG. 12, and FIG. 10
The inside screw 7 is shown.

[Effect of idea]

As described above, according to this invention, the lead feeding mechanism consisting of the lead chuck etc. and the lead pipe are formed separately with no gaps, so even if the eraser at the rear end of the lead pipe or the cap at the rear end is pulled out. , its withdrawal force does not affect the lead chuck at all, and therefore,
Breakage of the lead or breakage of the lead due to the lead chuck during drawing does not occur at all, and there is no risk of clogging with remaining lead or lead waste between the lead delivery mechanism and the lead pipe.

Further, according to this invention, since the first elastic body is provided between the core pipe and the core delivery mechanism to eliminate looseness between the two, problems such as core breakage and unsmooth operation can be avoided.

Further, as described above, since the relationships of a≧b and c≧d hold true, even if the sharp pencil is dropped, the lead can be reliably prevented from breaking.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a main part of a sharpening pencil according to an embodiment of the invention, FIG. 2 is a cross-sectional view of a main part of a sharpening pencil according to another embodiment of the invention, and FIG.
4 is a plan view of the sleeve, FIG. 5 is a sectional view taken along the line A-A in FIG. A sectional view of the main parts of the pencil, Figure 11 is the 10th
The top view of the screw in the figure, Figure 12 is A- in Figure 10.
13 is a longitudinal sectional view showing a conventional sharpening pencil, and FIG. 14 is a plan view of a conventional sharpening pencil. 1...Outer tube, 2...Core pipe, 3...Lead chuck, 5...Accessories, 7, 8...Middle screw, 9
...First elastic body, 11...Chuck tightening tube, 1
2... Second elastic body, 14... Core, 16... Sleeve, A... Core delivery mechanism, a... Gap, b... Distance, c... Gap, d... Distance.

Claims (1)

[Claims for Utility Model Registration] (1) A core pipe 2 that is slidably housed in the outer cylinder 1 in the axial direction, and a core pipe that is located in the outer cylinder 1 in front of the tip side of the core pipe 2 The lead delivery mechanism A includes a lead chuck 3 that bites the lead 14 that comes out from the core pipe 2 and extends into the lead delivery mechanism A, and a chuck tightening mechanism that acts on the lead chuck 3. It has a tube 11 and a second elastic body 12 that urges the lead chuck 3 in the tightening direction, and when the core pipe 2 is pressed and moved in the core feeding direction toward the lead delivery mechanism A side, the second elastic body 12 This is a sharp pencil in which the tightening force of the lead chuck 3 is released by the elastic body 12 being pressed by the lead pipe 2 to reduce the biasing force, the lead chuck 3 having the lead chuck 3 connected to the lead chuck 3. A is formed separately from the core pipe 2 and the core delivery mechanism A with no gap, and between the core pipe 2 and the core delivery mechanism A, the core pipe 2 and the core delivery mechanism A are biased so that they are in constant contact with each other, and the second elastic body 12 A first elastic body 9 having a weak biasing force is provided, and a gap a between the inner diameter of the lead chuck 3 and the outer diameter of the core 14 allows the lead chuck 3 to move within the outer cylinder 1 in the outer cylinder diameter direction. The gap c between the inner diameter of the core pipe 2 or its accessory part 5 and the outer diameter of the core 14 is at least the distance b, and the gap c between the inner diameter of the core pipe 2 or its accessory part 5 and the outer diameter of the core 14 is such that the core pipe 2 or its accessory part 5 is in the outer cylinder 1 in the outer cylinder diametrical direction. A sharp pencil characterized in that it can be moved over a distance d or more. (2) The core pipe 2 is prevented from rotating by engaging with the sleeve 16 or the internal threads 7 and 8 in the outer cylinder 1 fixed to the outer cylinder 1. A mechanical pencil according to claim 1 of patent registration.