JP3837840B2 - Sharp pencil - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sharp pencil in which a lead feeding mechanism is disposed inside a shaft cylinder, and a chuck body for gripping / releasing the lead and a lead tank for storing a plurality of lead are used as at least the structural requirements of the lead feeding mechanism.
[0002]
[Prior art]
One example is Japanese Utility Model Publication No. 53-124742. A conical core receiving part that separates a plurality of cores in the core tank is formed in the lower part of the core tank, and a chuck for gripping and releasing the core is provided below the core receiving part. A reduced diameter portion into which the body is press-fitted is formed. Further, the chuck body is press-fitted to an intermediate portion of the reduced diameter portion, and a step portion is formed between the lower end of the core receiving portion.
[0003]
[Problems to be solved by the invention]
However, in the above prior art, when the lead is gripped by the chuck body as shown in FIG. 1, the tip of the next lead slips and grips the conical part of the lead receiving part. The lower end portion comes into contact with the core, and the wedge effect acts here. The wedge action makes it difficult for the gripped core to be fed out, and it may become impossible to write.
In some cases, about two cores may simultaneously enter the inner diameter portion of the step formed between the upper end surface of the chuck body and the lower end of the core receiving portion. In such a case, the core is inserted into the chuck body. In some cases, the lead could not be penetrated, and the lead was raised at the stepped portion, making it impossible to feed the lead. This phenomenon occurs particularly when the gripped lead is shortened and the next lead enters the chuck body, or when a plurality of leads are inserted into a new sharp pencil.
[0004]
[Means for Solving the Problems]
The present invention has been made in view of the above problems, and a core feeding mechanism is arranged inside a shaft cylinder, and at least the core feeding mechanism includes a chuck body for gripping and releasing the core and a core tank for storing a plurality of cores. A sharp pencil as a constituent element of the mechanism, wherein a press-fit hole having an inner diameter smaller than the inner diameter of the core tank is provided in front of the core tank, the chuck body is fixed to the press-fit hole, and the chuck The rear end of the body is fixed in a state of protruding from the core receiving portion of the core tank, and the distance between the outer diameter of the rear end portion of the chuck body and the inner diameter of the core tank is set smaller than the diameter of the core to be used. The first gist is that a core feeding mechanism is arranged inside the shaft tube, a chuck body for gripping and releasing the core, a core tank for storing a plurality of cores, and an intervening space between the chuck body and the core tank. Disguised relay Shah and the claims of the at least the core feeding mechanism wood - a Pupenshiru, wherein forming the relay member to one core passage apertures core can pass, and also the rear end of the lead tank of the relay member The second gist is that the distance between the outer diameter of the rear end portion of the intermediate member and the inner diameter of the core tank is set smaller than the diameter of the core to be used while being fixed in a state of protruding from the core receiving portion. Is.
[0005]
【Example】
A first example will be described with reference to FIGS. A so-called compound writing instrument incorporating a ball pen and a sharp pencil will be described as an example. Inside the front shaft 1, a ball pen body 2 and a sharp pencil unit 3 are attached to the rear (hereinafter referred to as the rear in the figure and the lower as the front) by an elastic member 4 such as a coil spring. It is arranged so that it can be moved back and forth.
A rear shaft 6 to which the clip 5 is fixed is attached to the rear of the shaft tube 1 so as to move back and forth with respect to the shaft tube 1 and to be rotatable. Thereafter, a rod-like pendulum 7 is attached to the upper portion of the shaft 6 in a suspended state, and can be rotated (inclined) about the attachment portion 8. The rear shaft 6 is urged upward by a conical coil spring 9, and a cam groove 10 formed at the rear of the front shaft 1 and a cam projection 11 formed at the rear shaft 6. Due to the engagement, falling off (disassembling) from the front shaft 1 is prevented.
[0006]
Further, a pin 13 urged in the left direction in the figure by a spring 12 is disposed inside the rear shaft 6. On the other hand, the pin 13 is locked to the rear inner surface of the front shaft 1. A stepped portion 14 is formed. In the circumferential direction of the stepped portion 14, a concave portion 17 having an inclined protrusion 15 and an inner inclined surface 16 is formed.
Next, the operation method will be described. When the writing instrument (axis) is tilted, for example, in the right direction in the figure, the pendulum 7 is tilted about the mounting portion 8, and the tip thereof is located at the upper end portion of the ball pen body 2. When the rear shaft 6 is pressed downward in this state, the ball-point pen body 2 is pushed forward by the pendulum 7 and the pin 13 attached to the rear shaft 6 is locked to the step portion 14 of the front shaft 1. . Here, the ball-point pen body 2 protrudes from the front end of the front shaft 1 and the immersion is prevented.
In order to immerse the ball pen body 2 in the writing instrument (axis), the rear shaft 6 is rotated with respect to the front shaft. By this rotation operation, the pin 13 is retracted (raised) along the inclined surface 15 continuously formed with the locking step portion 14 and is finally dropped into the recess 17. At this time, the pin 13 returns to the (initial) state while being pressed by the action of the inner inclined surface 16 of the recess 17 and the elastic member 4. The pendulum 7 is also retracted and returned to the neutral position by the action of the coil spring 9.
[0007]
Next, the sharp pencil unit 3 that is a feature of the present invention will be described. A joint 20 having the same function as that of the core tank 19 is detachably fixed to the front end of the pipe-shaped core tank 19 having the cap 18 at the rear end. A core receiving portion 21 is attached to the lower end of the inner surface of the joint 20. A press-fitting hole 22 into which a chuck body to be described later is press-fitted is formed. A chuck body 23 for gripping and releasing the core is press-fitted and fixed in the press-fitting hole 22, and a core-passing hole through which one core can pass is provided at the center in the longitudinal direction of the chuck body 23. 23a is formed. Further, the rear end of the chuck body 23 is press-fitted in a state protruding from the inner surface of the core receiving portion 21. A chamfering process (outer peripheral chamfered part 25) is applied to the outer peripheral surface of the upper end of the projecting part 24 (of the chuck body) in order to eliminate burrs and returns when processed, and the inner peripheral surface also has a core. A chamfering process (inner peripheral chamfered portion 26) is applied so as to easily fall into the chuck body 23.
Further, the distance X between the inner diameter of the joint 20 and the outer diameter of the top portion 27 of the chuck body 23 formed by the outer peripheral chamfered portion 25 and the inner peripheral chamfered portion 26 is smaller than the diameter of the core used. .
[0008]
A chuck ring 28 for opening and closing the chuck body 23 is attached to the front portion of the chuck body 23 so as to surround it.
An outer shaft 29 is attached to the front of the joint 20 in an enclosed state, and the outer shaft 29 is urged forward by an elastic member 30. Further, a front member 31 is detachably fixed to the front end of the outer shaft 29 by screwing or the like, and a core that prevents the lead from retreating when the lead is fed out. A detent member 32 is press-fitted.
[0009]
Next, the operation will be described. Since the gap (distance X) formed by the inner diameter of the joint 20 and the outer peripheral diameter of the top portion 27 of the chuck body 23 is smaller than the diameter of the core used, the core does not enter the gap (distance X). Further, only one core can enter the chuck body 23.
Furthermore, since the rear end of the chuck body protrudes from the core receiving portion, the protruding amount may vary somewhat, so even if there are some dimensional variations in the overall length of the chuck body and joint, The variation can be absorbed by the protruding amount (the amount of press-fitting into the joint). In addition, no arrow or the like is formed on the rear side of the chuck body, which is easy to manufacture, and the inner surface of the core tank is not formed with a stepped portion for abutting the rear end of the chuck body. The tank is easy to manufacture.
[0010]
A second example will be described with reference to FIG. This is an example in which the outer diameter of the rear portion of the chuck body 33 is reduced. By forming the small-diameter portion 34, the chuck body 33 is shaken (center misalignment) and squeezed (shave) with respect to the press-fitting hole 22, which occurs when the chuck body 33 is assembled and press-fitted into the joint 20. This prevents entry of burrs (shavings) into the joint 20. Moreover, the uprightness in the temporary press-in of the chuck body and the joint before press-fitting is also good. Also in this example, the distance Y between the inner diameter of the joint 20 and the outer peripheral diameter of the top portion 35 of the chuck body 33 is smaller than the diameter of the core to be used.
[0011]
A third example will be described with reference to FIG. This is an example in which the lead tank 36 and the chuck body 37 are connected by a joint member 38 through which one lead passes. Also in this example, the rear end of the intermediate member 38 is fixed in a state of protruding from the core receiving portion 39 of the core tank 36, and the distance between the outer diameter of the rear end portion of the intermediate member 38 and the inner diameter of the core tank 35. Z is set smaller than the core using it. In the above example, since the chuck body protrudes from the core receiving portion of the core tank, the front end of the core and the rear end of the chuck body come into contact with each other, and the core separation is improved.
[0012]
【The invention's effect】
The present invention provides a sharp pencil in which a lead feeding mechanism is disposed inside a shaft cylinder, and a chuck body for gripping / releasing the lead and a lead tank for storing a plurality of lead are used as at least the structural requirements of the lead feeding mechanism. A press-fit hole having an inner diameter smaller than the inner diameter of the lead tank is provided in front of the lead tank, the chuck body is fixed to the press-fit hole, and the rear end of the chuck body is a core receiving portion of the lead tank. is fixed in a state that allowed more projecting, that is set smaller than the diameter of the core to use the distance between the inner diameter of the outer diameter and the lead tank of the rear end of the chuck body to the first aspect, the barrel A core feeding mechanism is arranged inside, a chuck body for gripping and releasing the core, a core tank for storing a plurality of cores, and a relay member interposed between the chuck body and the core tank at least of the core feeding mechanism. Structure Requirements and the Sha - a Pupenshiru, wherein forming the relay member to one core passage apertures core can pass, and also the rear end of the relay member in a state that allowed protruding from the core receiving portion of the lead tank Since the second gist is that the distance between the outer diameter of the rear end portion of the intermediate member and the inner diameter of the core tank is set to be smaller than the diameter of the core to be used, the chuck body is gripped by the chuck body Of course, the next core to follow and the core newly inserted into the sharp pencil can be easily and smoothly fed out.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of an essential part showing a first example of the present invention.
FIG. 2 is an enlarged perspective view of a main part of FIG.
FIG. 3 is a left side view of FIG.
4 is a longitudinal sectional view showing the sharp pencil unit of FIG. 1. FIG.
FIG. 5 is an enlarged view of a main part of FIG.
6 is an enlarged view of a main part of FIG.
FIG. 7 is a longitudinal sectional view of an essential part showing a second example.
FIG. 8 is a longitudinal sectional view showing a third example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Front shaft 2 Ball-pen body 3 Sharp pencil unit 4 Repelling member 5 Clip 6 Rear shaft 7 Pendulum 8 Mounting part 9 Coil spring 10 Cam groove 11 Cam protrusion 12 Spring 13 Pin 14 Step part 15 Inclination protrusion 16 Inner surface inclination Surface 17 recess 18 cap 19 core tank 20 joint 21 core receiving portion 22 press-fit hole 23 chuck body 24 projecting portion 25 outer peripheral chamfered portion 26 inner peripheral chamfered portion 27 top portion 28 chuck ring 29 outer shaft 30 elastic member 31 tip member 32 core return Stopping member 33 Chuck body 34 Small diameter portion 35 Top portion 36 Core tank 37 Chuck body 38 Relay member 39 Core receiving portion

Claims (2)

A sharp pencil having a lead feeding mechanism disposed inside a shaft cylinder and having a chuck body for gripping / releasing the lead and a lead tank for storing a plurality of lead as at least constituent elements of the lead feeding mechanism, A press-fit hole having an inner diameter smaller than the inner diameter of the core tank is provided in front of the chuck body, the chuck body is fixed to the press-fit hole, and the rear end of the chuck body is protruded from the core receiving portion of the core tank. A sharp pencil characterized in that it is fixed in a state and the distance between the outer diameter of the rear end of the chuck body and the inner diameter of the core tank is set smaller than the diameter of the core used. A core feeding mechanism is arranged inside the shaft cylinder, and a chuck body for gripping and releasing the core, a core tank for storing a plurality of cores, and a relay member interposed between the chuck body and the core tank are at least provided for the core. A sharp pencil as a constituent element of the feeding mechanism, wherein a core passage hole through which one core can pass is formed in the intermediate member, and a rear end of the intermediate member protrudes from a core receiving portion of the core tank A sharp pencil characterized in that it is fixed in a squeezed state and the distance between the outer diameter of the rear end of the intermediate member and the inner diameter of the core tank is set smaller than the diameter of the core to be used.

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