JPS6321637B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sharp pencil that supplies lead that wears out during writing in an amount equivalent to the amount of wear without changing the gripping condition of the sharp pencil during writing. .

Conventionally, this type of sharpening pencil was published in 1973
-125123 and 50-926 are proposed.
Although these proposals have made it possible to supply lead cores as described above, the following disadvantages still remain. That is, the guide pipe disclosed in JP-A-49-125123 and the lead guide disclosed in JP-A-50-926 must be resiliently repelled in the direction of the writing surface by a spring or the like.
When writing, it is necessary to write against the repulsive force of the spring; in other words, the guide pipe and lead guide must be pressed against the writing surface by the repulsive force of the spring. This is an inconvenience in that the brush strokes cannot be done smoothly. This inconvenience may even damage the writing surface if it is soft.

The present invention has been made to solve the above-mentioned conventional disadvantages, and will be described in more detail with reference to embodiments shown in the accompanying drawings.

In FIG. 1, reference numeral 1 is a main body, and the main body 1
A front member indicated by the reference numeral 2, an intermediate member 3 connected to the front member 2, a rear member 4 connected to the intermediate member 3, and an end closing the rear part of the rear member 4. It is composed of member 5. A hole 6 is provided in the tip member 2, and a lead core L is inserted into the hole 6.
A holding member 7 is attached to the rear part of the holding member 7 to lightly hold the tip member 7, and the front part thereof protrudes from the tip member 7, and a lead core guide tube 8 is disposed within the hole 6 so as to be able to freely move forward and backward. . A small diameter hole 9 into which the lead core L is loosely fitted is provided in the intermediate member 3. A lead core locking member 11 is slidably disposed in the small diameter hole 9, the front part of which abuts against the rear end of the lead core L, and the rear part of which is a tapered part 10. A hole 12 is provided in the rear member 4, and an engaging member 13 that can be positioned between the inner wall of the hole 12 and the tapered portion 10 is movably disposed within the hole 12. There is.

Next, the operation of this embodiment will be explained with reference to FIGS. 1 to 3.

The state shown in FIG. 1 indicates the start of writing, and when writing is started in this state, the main body 1 is pressed in the direction of the writing surface P by the pressure of writing. When the main body 1 is pressed as described above, since the lead L is pressed against the writing surface, the writing pressure is applied to the lead L and the lead in contact with the rear end of the lead L. It acts to press the locking member 11 in a direction opposite to the direction in which the main body 1 is pressed. When such a pressing force is applied to the lead core locking member 11, the lead core locking member 1
1 tries to move toward the rear of the main body 1, but the engaging member 13 tries to move toward the writing surface P (i.e., toward the front of the main body 1) due to its own weight and comes into contact with the tapered portion 10 and the inner wall of the hole 12. Because
With respect to the movement of the lead core locking member 11 described above, a wedge effect is produced by the tapered portion 10, the engaging member 13, and the inner wall of the hole 12, so that the lead core locking member 11 and the lead core L are attached to the main body 1. On the other hand, it is set in a fixed state. Therefore, when the main body 1 is pressed in the direction of the writing surface P, the lead L is pressed against the writing surface P, and writing is possible in this state. As you continue to write, the lead L will be consumed and worn by the amount of writing you do, but as this wears out, the lead guide tube 8 will also slide on the lead L while holding the lead L lightly by the holding member 6. and move backwards.
(See Figure 2). When the main body 1 is lifted and the tip of the lead lead L and lead guide tube 8 are moved away from the writing surface P after appropriate writing, the lead lead L and lead locking member 11 are removed.
The force applied to it is completely released. By releasing the force on the lead core locking member 11, the force that causes the wedge action between the tapered portion 10, the engaging member 13, and the inner wall of the hole 12 is also released. In this state, no external force is applied to the lead core L, the lead core locking member 11, the lead core guide tube 8, and the engaging member 13 other than their own weight, so the lead core guide tube 8 is attached to the lead core L.
At the same time, the main body 1 moves forward due to its own weight, and the rear part of the lead core guide tube 8 comes into contact with the inner front part of the tip member 2, thereby supplying the worn amount of the lead core L and stopping its movement. At the same time, since the force that causes the wedge action at the rear of the lead core locking member 11 is released as described above, the pressing force exerted by the tapered portion 10 on the inner wall of the hole 12 of the engaging member 13 is also eliminated, and therefore the lead core The locking member 11 also moves forward of the main body 1 by its own weight together with the engaging member 13, and the above-mentioned lead core guide tube 8
The movement of the object stops when the object stops. (See Figure 3). When the tip of the lead L is pressed against the writing surface P again in this state, a wedge effect is generated by the tapered portion 10, the engaging member 13, and the hole 12 as described above, and writing becomes possible. In this way, lead cores L are sequentially supplied as much as they are worn.

Next, the embodiment shown in FIG. 4 will be described. In this embodiment, the shapes of the engaging member 13 and the tapered portion 10 of the previous embodiment are changed, and the other structures are the same as those of the previous embodiment, and will therefore be omitted. Reference numeral 411 is a lead core locking member.
1 has a tapered portion 410 at the rear thereof, and a flange 412 is formed at the small diameter end of the tapered portion 410. Reference numeral 413 is a rolling element such as a sphere disposed between the tapered portion 410 and the inner wall of the hole 12 of the rear member 4.

Next, the operation of the embodiment shown in FIG. 4 will be explained. The wedge action and movement action are the same as in the previous embodiment, but in this embodiment, since the engaging member 413 is a rolling element, the wedge action can be released and the lead core locking member 411 can be smoothly moved. The flange 412 also has the function of preventing the engagement member 413 from detaching from the lead core locking member 411.

As described above, a main body, a lead core guide tube having a holding member for lightly holding a lead core inside the body disposed in the distal end portion of the main body so as to be freely moved forward and backward, and a lead core guide tube whose front portion is held by the lead core guide tube. a lead core locking member slidably disposed within the main body and capable of coming into contact with the rear end of the lead, and a lead core locking member movably disposed within the main body and engaging with the rear end of the lead core locking member According to the present invention, the supply for the wear of the lead lead L can be sequentially performed by separating the tip of the sharp pencil from the writing surface. There is no need to change the gripping position. Furthermore, during writing, the lead guide tube only lightly holds the lead through the holding member, so
This allows smooth retraction and provides a smooth writing feeling.

Incidentally, in each of the above embodiments, an example was described in which a wedge action was adopted as the engagement means, but the present invention is not limited to such a structure, and the writing pressure is applied to the lead. When pressure is applied to the lead, the lead locking member that comes into contact with the lead does not move toward the rear of the main body, and when the writing pressure on the lead is released, the lead locking member can easily move toward the front of the main body. Various such structures can be adopted.

[Brief explanation of the drawing]

Fig. 1 is a vertical sectional view showing an embodiment of the present invention, Fig. 2
3 and 3 are explanatory diagrams of the operation of the present invention, and FIG. 4 is a diagram showing another embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Main body, 7... Holding member, 8... Lead core guide tube, 11... Lead core locking member, 13... Engaging member.

Claims (1)

[Claims] 1. A main body, a lead core guide tube having a holding member that is arranged in the tip of the main body so as to be freely forward and backward and that lightly holds the lead core inside, and a rear part of the lead core whose front part is held by the lead core guide tube. a lead core locking member that is slidably disposed within the main body so as to be able to abut against the end portion; The engaging member is capable of coming into contact with the lead when writing pressure is applied to the lead, and prevents the lead locking member from moving toward the rear of the main body when writing pressure is applied to the lead. A sharp pencil that allows the lead locking member to move toward the front of the main body when released.