JP3885315B2 - Sharp pencil - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sharp pencil in which a chuck body for holding and releasing a core is disposed in a shaft cylinder.
[0002]
[Prior art]
Japanese Utility Model Laid-Open No. 4-104492 is known as a sharp pencil having a knocking member for operating the lead feeding mechanism at the rear end of a shaft cylinder of the sharp pencil incorporating the lead feeding mechanism. A cushion spring is provided at the rear of the chuck to prevent breakage of the core due to excessive writing pressure, and the elastic force of the cushion spring can be varied.
[0003]
[Problems to be solved by the invention]
However, in the above prior art, although the breakage of the core can be prevented by the cushion spring, if the writing is continued, the core is reduced in part, and the end surface of the core becomes elliptical, and as a result, the width of the writing line is reduced. It gradually became thicker. Here, in order to maintain the width of the thin writing line, there is a method of writing with a thin core, but the breaking strength is low because the core is thin. There is also a method of changing the writing instrument and rotating the writing instrument itself. That is, by rotating the writing tool itself, the lead is indirectly rotated, and the other end face of the lead is directed to the writing (paper) surface. However, such an operation is troublesome and troublesome because the writing instrument must be changed and rotated each time.
[0004]
[Means for Solving the Problems]
The present invention has been made in view of the above problems, and is a sharp pencil in which a chuck body for gripping and releasing a core is disposed in a shaft cylinder, and the core is gripped by the chuck body. In the state, a chuck body rotating means for rotating the chuck body by retreating the core is disposed in the shaft cylinder, and the chuck body rotating means is a rotor and a rotor that contacts the slider. And a cam portion provided on the inner wall surface of the shaft cylinder, and surrounds a chuck ring for opening and closing the chuck body at the front portion of the chuck body, and at the rear end of the chuck ring, A slider is brought into contact directly or via a core, and a rotor that moves as the slider moves is brought into contact with the slider. tea which is located in front of the child And click body, together with the rotor is biased forward by the elastic member, and there is not rotatable but to allow movement back and forth the slider relative to the barrel, the rear portion of the chuck body A lead tank is fixed to the lead tank, and the rotor cannot be rotated with respect to the lead tank, but it can be moved back and forth, and a lead protection tube is moved back and forth at the tip of the shaft cylinder. The gist is that the core protection tube is urged forward by a resilient member.
[0005]
【Example】
An example will be described with reference to FIGS. A core tank 2 for storing a plurality of cores is disposed in the shaft cylinder 1 so as to be movable back and forth (hereinafter, the lower side in the figure is referred to as the front and the upper side is referred to as the rear). A chuck body 3 for holding and releasing the core is fixed to the front end of the core tank 2, and a chuck ring 4 for opening and closing the chuck body 3 is inserted and attached to the chuck body 3. ing. Further, a tip member 5 is detachably fixed to the front end of the shaft tube 1 by means such as screwing, and a core detent member 6 is provided inside the tip member 5, A slider-8 having a core protection tube 7 attached to the tip is slidably (moving back and forth). Reference numeral 9 denotes a chuck spring having elasticity such as a coil spring that urges the chuck body 3 backward.
[0006]
A slider 10 is inserted into the core tank 2, and the front end of the slider 10 is in contact with the rear end of the chuck ring 4 via a core 11. 10 and the chuck ring 4 may be brought into direct contact with each other. On the other hand, longitudinal ribs 12 are formed at equal intervals on the outer periphery of the rear end of the slider 10, and the rear end surface of the slider 10 is a mountain-shaped protrusion whose top is a portion that contacts the longitudinal rib 12. A plurality of 13 are formed at equal intervals.
The protrusion 13 is engaged with a cam portion 14 formed on the inner wall surface of the intermediate portion of the shaft tube 1. More specifically, the cam portion 14 has a longitudinal projection 15 that is long in the longitudinal direction with respect to the shaft cylinder 1 and a length shorter than the longitudinal projection 15 and smaller than the inner diameter of the shaft cylinder 1. The upper end surface of the vertical protrusion 15 and the upper end surface of the vertical groove portion 16 are connected by an inclined surface 17. A plurality of the vertical protrusions 15 and the vertical groove portions 16 are formed at equal intervals on the inner peripheral surface of the shaft tube 1. Here, the longitudinal ribs 12 (mountain-shaped protrusions 13) of the slider 10 are engaged with the longitudinal groove portions 16 of the cam portion 14, and are not rotatable with respect to the cam portion 14 (shaft cylinder 1). Yes, but it can move up and down.
[0007]
A rotor 18 is urged forward by an elastic member 19 and abuts the upper end of the slider 10. The rotor 18 has a vertical protrusion 20 on the outer peripheral portion, and an inclined surface 21 is formed at the lower end of the vertical protrusion 20. The vertical protrusion 20 is in contact with the inclined surface 17 of the cam portion 14.
A through hole 22 through which the core tank 2 passes is formed at the center of the rotor 18, but the rotor 18 and the core tank 2 are not rotatable but can be moved in the vertical direction. It has become. Specifically, a recess 23 is formed at a position opposite to the through hole 22, and a protrusion 24 formed on the core tank 2 is engaged with the recess 23 (see FIG. 3). .
[0008]
A spring receiver 25 is fixed to the rear of the rotor 18 to prevent the elastic member 19 from moving backward (dropping off).
Further, an inner peripheral projection 29 is formed inside the tip member 5 and behind the slider-8. An elastic member 30 such as a coil spring is stretched between the inner peripheral projection 29 and the slider-8 to urge the slider-8 forward. Incidentally, the urging force of the elastic member 30 is set to be larger than the holding force for holding the lead L by the lead detent member 6. That is, even if the lead L moves backward, the slider 8 moves forward by sliding on the surface of the lead L.
Further, an eraser holder 27 holding an eraser 26 is detachably press-fitted to the rear end of the core tank 2. A knock (eraser) cap 28 that also serves as a pressing operation section is detachably press-fitted into the eraser holder 27.
[0009]
Next, the operation will be described. When the lead is extended, the knock (eraser) cap 28 is pressed in the same manner as a general sharp pencil. By this pressing operation, the lead tank 2 moves forward while sliding through the through hole 22 of the rotor 18. As the lead tank 2 moves forward, the chuck body 3 moves forward. At this time, the lead L is also moved forward, and the chuck body 3 expands eventually. Here, when the pressing operation of the knock cap 28 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 lead is reduced and the writing line becomes thick during writing, the lead L is pressed slightly against the paper (writing surface) during writing. By this pressing operation, the lead L moves backward and the slider 8 also tries to move backward, but the slider 8 is moved forward by the elastic member 30 so that the tip of the lead protection tube 9 and the tip of the lead L are connected. They are in a flush state (see FIG. 5). Further, the chuck body 3 and the slider 10 are retracted by the retraction operation of the core L, and preparation for the rotation operation of the core L is made. Here, when the protruding amount of the core L from the core protection tube 9 is relatively large, the core L is rotated.
When the core L is further pressed against the paper surface in the above state, the slider 8 moves backward together with the core L (see FIG. 6). At this time, the chuck body 3 and the chuck ring 4 holding the core L are also retracted. Further, as the chuck ring 4 moves backward, the slider 10 moves backward, and the rotor 18 moves backward while resisting the elastic member 19 by moving the slider 10 backward. Then, by the retreating operation of the rotor 18, the protrusion 17 of the rotor 18 reaches the top of the vertical protrusion 15 of the cam portion 14, and eventually slides down while rotating on the inclined surface 17 of the next (adjacent) vertical protrusion 15 ( It moves forward and returns to the base position: see FIG. The engagement state between the protrusion 13 of the slider 10 and the inclined surface 21 of the rotor 18 gives the rotor 18 a turning stake, and then the engagement state between the inclined surface 21 and the inclined surface 17 The rotor 18 rotates while moving forward by the urging force of the elastic member 19. The core tank 2 is rotated by the rotation of the rotor 18, and the chuck body 3 fixed to the core tank is rotated. Then, the core L held by the rotation of the chuck body 3 also rotates.
In this example, when the lead L is retracted (applying a pressing action), the slider 8 moves forward, so that the tip of the lead L is covered, and breakage of the lead L due to the pressing operation force can be prevented. it can.
Note that, depending on the setting of the resilience of the resilient member 19, specifically, if the resilience is reduced, it can be rotated each time the core is separated from the paper surface.
Further, even when the core L protrudes only slightly from the core protection tube 7, specifically, even when there is no protrusion amount until the rotor 18 reaches the top of the inclined surface 17 of the cam portion 14, the slider- Since 8 moves backward (with the core L), the core L can be rotated. Moreover, since the core (chuck body) is retracted by pressing the core against the paper surface, the cushioning action works as in the prior art, and the breakage of the core can be prevented.
[0011]
【The invention's effect】
The present invention provides a sharp pencil in which a chuck body for gripping and releasing a core is disposed in a shaft cylinder, and the chuck is retracted by retracting the core in a state where the core is gripped by the chuck body. The chuck body rotating means for rotating the body is disposed in the shaft cylinder, and the chuck body rotating means is provided on the slider, the rotor that contacts the slider, and the inner wall surface of the shaft cylinder. A chuck portion that surrounds a chuck ring that opens and closes the chuck body at the front portion of the chuck body, and directly or via a core at the rear end of the chuck ring. The rotor that moves with the movement of the slider is brought into contact with the slider, and the slider , the chuck body positioned in front of the slider , and the rotation by the elastic member of the child Write to is energized, also with some not rotate but to allow movement back and forth the slider relative to the barrel, a lead tank is fixed to the rear of the chuck body, wherein on the lead tank Although the rotor cannot be rotated with respect to the core tank, it is arranged so that it can move back and forth, and a core protection tube is attached to the tip of the shaft cylinder so that it can be moved back and forth. Therefore, the lead can be rotated by a simple operation of simply pressing the lead against the paper surface, so that the lead is not reduced and a writing line having a certain width can be drawn.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing an example of the present invention.
FIG. 2 is a partial cross-sectional perspective view showing main parts.
FIG. 3 is a cross-sectional view taken along line AA in FIG.
4 is an enlarged longitudinal sectional view of a main part of FIG.
FIG. 5 is an enlarged longitudinal sectional view showing a main part showing the rotation operation of the core.
FIG. 6 is an enlarged longitudinal sectional view showing a main part showing the rotation operation of the core.
[Explanation of symbols]
1 shaft cylinder 2 core tank 3 chuck body 4 chuck ring 5 tip member 6 core detent member 7 core protection tube 8 slider
DESCRIPTION OF SYMBOLS 9 Chuck spring 10 Slider 11 Core 12 Vertical rib 13 Protrusion 14 Cam part 15 Vertical protrusion 16 Vertical groove part 17 Inclined surface 18 Rotor 19 Repellent member 20 Vertical protrusion 21 Inclined surface 22 Through-hole 23 Concave part 24 Protrusion part 25 Spring Receiver 26 Eraser 27 Eraser holder
28 Knock cap 29 Circumferential protrusion 30 Elastic member

Claims (1)

A sharp pencil in which a chuck body for gripping and releasing a core is disposed in a shaft cylinder, and the chuck body is rotated by retracting the core while the core is gripped by the chuck body. The chuck body rotating means is disposed in the shaft cylinder, and the chuck body rotating means includes a slider, a rotor in contact with the slider, and a cam portion provided on the inner wall surface of the shaft cylinder. A chuck ring for opening and closing the chuck body is surrounded by a front portion of the chuck body, and the slider is brought into contact with the rear end of the chuck ring directly or via a core. The rotor that moves as the slider moves is brought into contact with the slider, and the slider , the chuck body positioned in front of the slider , and the rotor are elastically moved. urged forward by a member Were also with some not rotate the slider relative to the barrel but allows the movement back and forth, a lead tank is fixed to the rear of the chuck body, the core of the rotor to the lead tank Although it is not rotatable with respect to the tank, it is arranged so that it can move back and forth, and a core protection tube is attached to the tip of the shaft cylinder so that it can be moved back and forth. Sharp pencil characterized by