JPS6316279B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION In addition to being able to center the sharp pencil using the rear end notch like a normal sharp pencil, the present invention also allows for centering with the tip of the sharp pencil, or with the core that protrudes further from the tip of the sharp pencil. The present invention relates to a sharp pencil that can be centered by notching the tip (hereinafter referred to as tip notching), and is improved so that only a slight force is required when the tip is notched.

Regarding a sharpening pencil in which centering is possible with both the rear end notch and the tip notch, the applicant has
An application has already been filed for the structure shown in FIG.
To briefly explain this, by pressing against the paper surface etc. with the tip notch, the slider 3 integrated with the core tube 2 and the chuck device 4 that grips the core A are retreated into the shaft tube 1 without changing their mutual positional relationship. At that time, the elastic member 5 for the slider and the elastic member 6 for the tip and rear end notches were compressed, and the protrusion 3a of the slider 3 was engaged and locked with the locking member 7 on the shaft cylinder 1 side. Also, I will relieve the pressure on the paper etc. mentioned above. By releasing the pressure on the paper surface etc. in this way, the chuck device 4 and the core A gripped by the chuck device 4 are moved forward together with the restoring force of the elastic member 6 against the stationary slider 3, thereby centering. will be carried out. Eventually, the front end of the chuck actuating tube 10 of the chuck device 4 collides with the rear end of the slider 3, and the slider 3 is unlocked and returned to its initial position by the restoring force of the slider resilient member 5. The chuck device 4 likewise returns to its initial position. When the slider 3 returns, the core entraining member 12 of the slider 3
When a tensile force acts on the chuck body 8 of the chuck device 4 that grips the core A through the core A held by the core A, the chuck elastic member 11, which has a weak force, is compressed and the chuck body 8 and the trochanter 9 are compressed. Since the chuck force is weakened by advancing the lead A, the lead A can be pulled out from the chuck device 4 using the lead holding force of the lead-carrying member 12. As a result, the tip notch provides a centering length equal to the distance between the rear end of the slider 3 and the front end of the chuck device 4.

By the way, in order to pass the core A in the core storage tube 13 overcoming the resistance of the core-carrying member 12 at the beginning of use, etc., a known centering mechanism using a rear end notch is adopted.
As for the structure for this purpose, the elastic member 6 for the tip and rear end notches is connected to the rear cylinder 10 of the chuck operating tube 10.
The rear end surface of the seat body 14 is slidably fitted into the rear cylinder 10a and comes into contact with the locking part 10b, such as a step, provided on the rear cylinder 10a, and the front step 1a of the shaft cylinder 1, so that it cannot move forward any further. and the front end surface of the protrusion 13a of the core storage tube 13 which abuts against the rear stepped portion 1b of the shaft tube 1 and cannot retreat any further. Fit it into the front cylinder 13b of No. 13 somewhat tightly. Reference numeral 15 indicates such a friction fit location. Assuming that the rear end is clicked in accordance with the conventional method, the friction fit point 15 will remain until the chuck device 4 in the closed state comes into contact with the rear end of the slider 3.
Although sliding does not occur at the front end surface 13c of the core storage tube 13, sliding at the friction fit point 15 starts by applying a pressing force from the rear end notch even after contact, and the front end surface 13c of the core storage tube 13
Press the end surface 8a of the chuck body 8 with
The trochanter 9 moves forward and the chuck opens. After that, when the pressure by the rear end notch is stopped and the chuck device 4 is moved backward by the restoring force of the resilient member 6, the locking portion 10b of the chuck actuating tube 10 is
The chuck remains open and the overlap at the friction fit point 15 remains deep until it is prevented from moving back, such as by bumping into the friction fit point 15, but after that, sliding at the friction fit point 15 begins. Return to the beginning of the overlap,
The end surface 8a of the chuck body 8 and the front end surface 13c of the core storage tube 13 are separated, and the chuck elastic member 1
Since the chuck is closed with a return force of 1 and thus returns to the initial state, the desired centering operation can be performed by repeating the above operations.

In the case of the above-mentioned structure, if we consider again the pressing force at the time of the tip notch, we can see that the force required to compress the tip and rear end notch elastic members 6 and the slider elastic member 5 and the friction fit point 15 A force greater than the sum of the frictional resistance forces is required. However, as mentioned above, the friction fitting portion 15 is not originally involved in the centering function of the tip notch at all, and only increases the pressing force when the tip notch is pressed by the frictional resistance force. .

It can be said that the frequency with which inconveniences such as lead breakage occur with the tip of the tip that pushes the core tube 2 or the tip A is proportional to the strength of the pressing force when the tip is pressed, so it is desirable that the pressing force be equal to the pressure used during normal writing. The goal is to make sure that it is a minor problem that does not cause a setback.

Although the present invention can satisfy the above-mentioned requirements, for convenience of comparison with FIG.
The following is an explanation of the embodiments of the present invention shown in the figures to FIG. 3.

As mentioned above, in the case of FIG. 4, one elastic member 6 is used for both the tip and rear end notches,
The rear end of the elastic member 6 was supported by the rear stepped portion 1b of the shaft tube 1. On the other hand, in the present invention, the elastic member 6a for the front end notch and the elastic member 6a for the rear end notch.
The rear end of the tip notch resilient member 6a is supported by the rear step portion 1b of the shaft cylinder 1. A connecting member 16 having one end as a front portion 14'
is provided, and the front end of the tip notch resilient member 6a is supported by the rear end surface of the seat portion 17 formed at the rear end of the member 16. The resilient member 6b for the rear end notch is connected to the connecting member 16.
The protrusion 1 is stretched between the rear end surface of the front part 14' and the front end surface of the protrusion 13a of the core storage tube 13.
The rear end surface of 3a is supported by the front end surface of the seat portion 17. Other than the above-mentioned differences, everything else is the same as the example shown in FIG.

That is, in the present invention, the front part 14' of the connecting member 16 whose rear end is the seat part 17 is slidably fitted into the chuck operating pipe 10, and the locking part 1 of the chuck operating pipe 10 is
0b as well as the front step portion 1a of the shaft tube 1. A resilient member 6a for a tip notch is provided between the rear end surface of the seat portion 17 and the rear step portion 1b of the shaft cylinder 1.
Stretch it. The protrusion 13a of the core storage tube 13, which is in a somewhat tight fitting relationship with the chuck operating tube 10, is made engageable with the front end surface of the seat 17, and the rear end surface of the front portion 14' and the front end surface of the protrusion 13a are Its feature lies in the structure in which the rear end notch elastic member 6b is stretched between the two.

In such a configuration, the connecting member 16 and the seat portion 17 at the rear end are connected to the fourth
It corresponds to the shaft cylinder 1 and its rear stepped portion 1b in the figure, and since the presence of the tip notk elastic member 6a can be ignored, it is clear that even with this structure, centering operation can be performed without any blemish by the rear end notch. Explanation will be omitted.

Next, regarding the tip notch, the tip is first put in the state shown in Fig. 1, and the slider 3 integrated with the core tube 2 and the chuck device 4 for gripping the core A are attached without changing their relative positions. The slider 3 is retracted into the shaft cylinder 1 as shown in FIG.
In the process of engaging and locking the locking member 7 provided in the locking groove 1c on the shaft cylinder 1 side, the tip notch elastic member 6a is compressed via the connecting member 16, but the inside of the connecting member 16 is Resilient member 6 for the rear end notch to be stretched
b is not compressed, and the friction fit point 1
No sliding occurs at step 5 either. After locking the slider 3 in the retreated position, the pressure by the tip notch is released, and the chuck device 4 is advanced by the return force of the tip notk elastic member 6a, as shown in FIG. Even in the process of releasing the lock of the slider 3 by colliding the front end with the rear end of the slider 3, no sliding occurs at the friction fitting portion 15. Furthermore, the process of returning from the state shown in FIG. 3 to the state shown in FIG. Therefore, a slight pressing force is sufficient when the tip is notched since there is no frictional resistance at the friction fitting portion 15, which is extremely effective in preventing core breakage and wear and tear of the sliding part of the slider 3 when the tip is notched. It is.

[Brief explanation of the drawing]

1 to 3 are sectional views showing an embodiment of the present invention in the order of operation of the tip end knob, and FIG. 4 is a sectional view corresponding to FIG. 1 of an embodiment other than the present invention. DESCRIPTION OF SYMBOLS 1... Shaft cylinder, 1a... Front step part, 1b... Rear step part, 6a... Resilient member for tip notch, 6b...
Resilient member for rear end notch, 10...chuck operating tube, 13...core storage tube, 14'...front part, 16...
...Connecting member, 17... Seat part.

Claims (1)

[Claims] 1. A connecting member 16 whose rear end is a seat portion 17 is slidably fitted into the chuck operating tube 10 and can be locked to the locking portion 10b of the chuck operating tube 10 and the front step portion 1a of the shaft tube 1. A tip notch elastic member 6a is stretched between the rear end surface of the seat portion 17 and the rear end surface 1b of the barrel 1, and the core storage tube 13 is in a slightly tight fitting relationship with the chuck actuating tube 10. The protrusion 13a can be engaged with the front end surface of the seat 17, and a rear end notching elastic member 6b is stretched between the rear end surface of the front part 14' of the connecting member 16 and the front end surface of the protrusion 13a. A sharpening pencil with a notched tip.