JPS641109Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a sharp pencil with a lead return mechanism that not only allows the lead to be fed out using a rear end notch method, but also allows the lead to be returned to the lead storage portion after use.

In a conventional sharp pencil having a lead detent member, after use, the lead is held by the lead detent member and then clamped by the chuck. Even when the chuck is set in the expanded state, it is firmly held by the core detent member. Therefore, it cannot be returned to the core tank. However, if the lead can be returned to the lead tank, the risk of lead breakage due to external impact can be greatly reduced, and it will also be possible to develop new sharp pencils with a revolver-type lead storage structure. shall be.

By the way, the applicant devised the U.K. 50-
Publication No. 827 discloses a protection mechanism in which an operating cylinder with a spiral cam groove is rotatably provided on the shaft cylinder, and a fixed linear cam groove is also provided, with a protruding knob that engages with both cam grooves. A pipe is disposed between the operating barrel and the shaft barrel, so that the protective pipe can be moved in and out by rotating the operating barrel, and the narrow rod for guiding the lead at the tip of the sharp pencil is covered by the protective pipe when carried. , a device to protect this has been disclosed. This retracting mechanism is extremely simple in structure and operation. Therefore, by applying this mechanism, the inventor of the present invention
I considered whether it would be possible to remove the core detent member from the chuck that was holding the lead and thereby release the inserted state between the core and the core detent member, and after various studies, I was able to complete the present invention. Ta.

In other words, the present invention rotatably provides an operation cylinder in which a spiral cam groove is formed on a shaft cylinder equipped with a chuck mechanism that allows the core to be fed out by operating a rear end notch.
A slider with a fixed linear cam groove and a protruding knob that engages with both cam grooves is placed between the operation cylinder and the shaft cylinder, and a core detent member is installed inside the slider. It is a sharpening pencil with a mechanism.

The present invention will be described in detail with reference to embodiments shown in the drawings.

In FIG. 1, reference numeral 1 denotes a shaft cylinder consisting of a small-diameter front portion 1a and a large-diameter rear portion 1b. The rear end of the large-diameter rear portion 1b is open to allow a portion of a core tank 6, which will be described later, to protrude. The small diameter front portion 1a ends at the sliding guide portion 2 of the chuck ring 3, and the core detent member 12 is not attached. However, the shaft cylinder 1 includes a chuck ring 3 that can move back and forth within the sliding guide 2, a chuck 4 that fits inside the chuck ring 3, and a chuck spring 5 that biases the chuck 4 backward.
A core tank 6 is equipped with a known chuck mechanism consisting of the following parts and is connected to the rear of the chuck 4.
The lead can be fed out by operating the rear end notch.

The operating cylinder 8 has a spiral cam groove 7 formed on its inner surface.
It is the same as the prior art described above in that it is rotatably attached to the front end of the large-diameter rear portion 1b and that a linear cam groove 10 is provided opposite the spiral cam groove 7. The spiral cam groove 7 may be formed directly on the inner surface of the operating barrel 8, or a ring-shaped member 9 formed with the spiral cam groove 7 as shown in FIG. 4 may be attached to the inner surface of the operating barrel 8. You can do it like this. Like the spiral cam groove 7, the linear cam groove 10 may also be formed directly on the outer surface of the small diameter front portion 1a of the shaft cylinder 1, or the linear cam groove 10 as shown in FIG. As shown in FIG. 1, the formed ring-shaped member 11 may be fixed by inserting one end into the continuous stepped portion of both portions 1a and 1b.

The core detent member 12 is attached to a slider 13 that is separate from the barrel 1, and the slider 13 is disposed between the operating barrel 8 and the small diameter front portion 1a of the barrel 1, and is provided protruding from the slider 13. The knob 14 is engaged with both cam grooves 7 and 10. In the illustrated example, the knob 14 protrudes only on one side, but when the linear cam groove 10 is directly bored into the shaft cylinder 1,
It will protrude on both sides.

The first core 15 is held by the chuck 4.
To return the wick 15 to the wick tank 6 from the state shown in the figure,
The knob 14 of the slider 13 is pushed by the spiral cam groove 7 by rotating the operating cylinder 8, and guided by the linear cam groove 10, so that the slider 13 and the core detent member 12 installed therein are moved straight. In this way, the inserted state between the core 15 and the core detent member 12 is finally released, as shown in FIG. Next, as shown in Fig. 3, by performing a rear end knock operation, the chuck 4 is expanded, and by pointing the tip of the sharp pencil upward, the lead 15 falls into the lead tank 6 under its own weight. I can do it. When the rear end knob operation is released, the mouth of the chuck 4 is closed again, and when the operating cylinder 8 is rotated in the opposite direction, the slider 13 returns to the state shown in FIG. 1. Note that normal centering is performed regardless of the operation tube 8.
It goes without saying that this can be done by operating the rear end knob.

As described above, although the present invention is extremely simple in both structure and operation, it is possible to release the inserted state between the core 15 and the core detent member 12, which is the original purpose of the present invention. It is extremely superior in that the core can be returned.

[Brief explanation of the drawing]

Figures 1 to 3 are cross-sectional views sequentially showing the states of the sharp pencil according to the present invention when re-centering, and Figures 4 and 5 show the formation of a spiral cam groove and a linear cam groove. It is a perspective view showing an example when doing so. DESCRIPTION OF SYMBOLS 1...Shaft cylinder, 2...Chuck ring sliding guide part, 3...Chuck ring, 4...Chuck, 5
...Chuck spring, 7...Spiral cam groove, 8...
Operation barrel, 10... linear cam groove, 12... core detent member, 13... slider, 14... knob.

Claims (1)

[Scope of utility model registration request] The shaft cylinder 1 is equipped with chuck mechanisms 2, 3, 4, and 5 that can feed out the core by operating a rear end notch, and is rotatably provided with an operation cylinder 8 in which a spiral cam groove 7 is formed, and a fixed linear cam. A slider 13 having a groove 10 and a protruding knob 14 that engages with both cam grooves 7 and 10 is disposed between the operating cylinder 8 and the shaft cylinder 1, and a core detent member 12 is installed inside the slider 13. A sharp pencil with a core return mechanism.