JPH10329485A - Mechanical pencil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To only press a lead to a paper face so that the lead is rotated and thereby, eliminate the one-sided wear of the lead to form a writing line of constant width by providing a chuck for holding and releasing the lead in a shaft barrel and at the same time, arranging a rotary means for rotating the chuck through the backward movement of the lead. SOLUTION: A lead L is pressed to a paper face slightly strongly when the writing tip of the lead is thick due to the uneven wear of the lead during writing. Consequently, a chuck ring 4 moves backward by a pressing action through a chuck 3 holding the lead L. In addition, following the backward movement of the chuck ring 4, a sliding element 8 recedes to cause even a rotor 15 to move backward. As a result of this receding action of the rotor 15, the protrusion 17 of the rotor 15 reaches the top of a longitudinal protrusion 12 of a cam part 11, and slides down rotating over the inclined plane 14 of an adjoining longitudinal protrusion 12. The rotation of the rotor 15 is triggered by the engagement between the protrusion 10 of the sliding element 8 and the inclined plane 18 of the rotor 15, and next, the rotor 15 is caused to rotate by the engagement between the inclined plane 18 and the inclined plane 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sharp pencil in which a chuck body for gripping and releasing a core is disposed in a shaft cylinder.

[0002]

2. Description of the Related Art A sharp pencil having a knock member for actuating the centering mechanism is provided at the rear end of a shaft cylinder of a sharpening pencil having a centering mechanism.
-104492 is known. A cushion spring is provided at the rear of the chuck to prevent breakage of the core due to excessive writing pressure and to change the elasticity of the cushion spring.

[0003]

However, in the above prior art, although the breakage of the core can be prevented by the cushion spring, the core is reduced by writing and the end face of the core becomes elliptical. As a result, the width of the writing line gradually increased. Here, in order to maintain the width of the writing line in a thin state, there is a method of writing with a core having a small diameter. However, the breaking strength is reduced because the core is thin. There is also a method of changing the writing implement and rotating the writing implement itself.
That is, by rotating the writing implement itself, the lead is indirectly rotated, and the other end face of the lead is directed to the writing (paper) surface. However, each time the writing instrument must be changed and rotated, the operation is troublesome,
It was also annoying.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and is directed to a sharp pencil in which a chuck body for gripping / releasing a core is disposed in a shaft cylinder. And a chuck body rotating means for rotating the chuck body by the retreating operation.

[0005]

1 and FIGS. 3 to 6 show an example. A core tank 2 for storing a plurality of cores is disposed inside the barrel 1 so as to be movable back and forth (hereinafter, the lower side in the figure is referred to as front, and the upper side is referred to as rear). A chuck body 3 for holding and releasing the lead is fixed to the front end of the lead tank 2, and a chuck ring 4 for opening and closing the chuck body 3 is inserted and attached to the chuck body 3 in a surrounding state. ing. Further, a tip member 6 having a core detent member 5 provided therein is detachably fixed to the front end of the barrel 1 by means such as screwing. Reference numeral 7 denotes a resilient chuck spring such as a coil spring for urging the chuck body 3 forward.

A slider 8 is inserted into the core tank 2, and the front end of the slider 8 is in contact with the rear end of the chuck ring 4 via a core N. As shown in FIG. 2, the slider 8 and the chuck ring 4 may be directly in contact with each other. On the other hand, vertical ribs 9 are formed at equal intervals on the outer periphery of the rear end of the slider 8, and the rear end surface of the slider 8 has a mountain-like shape such that a portion corresponding to the vertical rib 9 is a top. Are formed at equal intervals. The protrusion 10
Is engaged with a cam portion 11 formed on the inner wall surface of the intermediate portion of the barrel 1. More specifically, the cam portion 11
Is a longitudinal projection 12 longer in the longitudinal direction with respect to the barrel 1, a length shorter than the longitudinal projection 12, and having a smaller inner diameter than the inner diameter of the barrel 1 but larger than the inner diameter of the vertical projection 12. The upper ends of the vertical projections 12 and the upper ends of the vertical grooves 13 are connected by an inclined surface 14. A plurality of the vertical projections 12 and the vertical groove portions 13 are formed at equal intervals on the inner peripheral surface of the shaft cylinder 1. here,
The protrusion 10 of the slider 8 is engaged with the vertical groove 13 of the cam portion 11 and cannot rotate with respect to the cam portion 11 (the shaft cylinder 1), but can move in the vertical direction. Has become.

[0007] The rotor 1 is provided at the upper end of the slider 8.
5 is urged forward by a repelling member 16 and is in contact therewith. The rotor 15 has a vertical projection 17 on an outer peripheral portion, and an inclined surface 18 is formed at a lower end of the projection 17. The vertical projection 17 is provided on the cam portion 11.
Abuts on the inclined surface 14. A through hole 19 through which the core tank 2 penetrates is formed in the center of the rotor 15, and the rotor 15 and the core tank 2 cannot rotate, but can move in the vertical direction. It has become. Specifically, at the position facing the through hole 19, the recess 2 is provided.
0 is formed, and the protrusion 21 formed on the core tank 2 is engaged with the recess 20 (see FIG. 4).

A spring receiver 22 for preventing the elastic member 16 from moving backward (dropping) is fixed behind the rotor 15. At the rear end of the core tank 2, an eraser holder 24 holding an eraser 23 is press-fitted detachably. A knock (eraser) cap 25 also serving as a pressing operation portion is detachably press-fitted into the eraser holder 24.

Next, the operation will be described. When the lead is extended, the knock (eraser) cap 25 is pressed in the same manner as a general sharp pencil. By this pressing operation, the lead tank 2 moves forward while sliding in the through hole 19 of the rotor 15. The chuck body 3 advances with the advance of the core tank 2, and at this time, the core L also advances, and the chuck body 3 expands soon. Here, when the pressing operation of the knock cap 25 is released, the lead tank 2 and the chuck body 3 retreat, and the lead L is gripped again. This completes the feeding of the lead.

[0010] If the core is reduced during writing and the writing pad becomes thicker, the core L is pressed slightly strongly on the paper surface (writing surface) during writing. By this pressing operation, the chuck ring retreats via the chuck body 3 holding the core L. Further, with the retraction of the chuck ring 4, the slider 8 retreats and the rotor 1
5 is also retracted (see FIG. 6). By the retreating operation of the rotor 15, the projection 17 of the rotor 15
Reaches the top of the vertical projection 12 and then the next (adjacent) vertical projection 1
2 while sliding down on the inclined surface 14 (moving forward and returning to the original position). The engagement state between the protrusion 10 of the slider 8 and the inclined surface 18 of the rotor 15 gives the rotor 15 a start of rotation, and then the inclined surface 18 and the inclined surface 14.
It rotates according to the state of engagement with. Here, depending on the setting of the resilient force of the resilient member 16, specifically, if the resilient force is reduced, the core can be rotated each time the core is separated from the paper surface. As a result of the above operation, the core tank 2 is rotated by the rotation of the rotor 15, and the chuck body 3 and the core L held by the chuck body 3 rotate. By pressing the core against the paper, the core (chuck body) retreats, so that the cushioning function works as in the prior art.
Breaking of the core can also be prevented.

[0011]

According to the present invention, there is provided a sharp pencil in which a chuck body for gripping and releasing a core is disposed in a shaft cylinder.
Since the chuck body is provided with chuck body rotating means for rotating the chuck body by the retreating operation of the core, the core can be rotated by a simple operation of merely pressing the core against the paper surface, and therefore, there is no loss of the core. , You can draw a line with a certain width.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a first example of the present invention.

FIG. 2 is a longitudinal sectional view showing a modification.

FIG. 3 is a partial cross-sectional perspective view showing main parts.

FIG. 4 is a sectional view taken along line AA of FIG. 1;

FIG. 5 is a vertical cross-sectional view showing a core feeding operation.

FIG. 6 is a longitudinal sectional view showing the rotation operation of the core.

[Explanation of symbols]

 Reference Signs List 1 shaft cylinder 2 core tank 3 chuck body 4 chuck ring 5 core detent member 6 tip member 7 chuck spring 8 slider 9 vertical rib 10 protrusion 11 cam portion 12 vertical protrusion 13 vertical groove portion 14 inclined surface 15 rotor 16 repellent Member 17 Vertical protrusion 18 Inclined surface 19 Through hole 20 Depression 21 Projection 22 Spring receiver 23 Eraser 24 Eraser holder 25 Knock cap

Claims (1)

[Claims] 1. A sharp pencil in which a chuck body for gripping and releasing a core is disposed in a shaft cylinder, said chuck pencil including chuck body rotating means for rotating said chuck body by a retracting operation of the core. .