JPS6139594Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention is designed to supply 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. This is about a sharpening pencil.

(Prior art and its problems) Conventionally, this type of sharpening pencil was published in Japanese Patent Application Publication No. 49.
-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 JP-A-50-926
The lead guide disclosed in the above issue must be resiliently repelled in the direction of the writing surface by a spring or the like, so when writing, it is necessary to write against the repulsive force of the spring, in other words, the guide It is inconvenient that writing must be performed with the pipe and lead guide pressed against the writing surface by the resiliency of the spring, and therefore the writing cannot be done smoothly. This inconvenience may even damage the writing surface if it is soft.

(Purpose of the invention) The present invention solves the above-mentioned conventional inconveniences, and also in cases where the main body is accidentally dropped and an impact force is applied to the lead guide, or when the lead lead breaks against the lead during writing. This is intended to absorb the impact force or writing pressure and prevent the lead from breaking when writing pressure is applied.

(Example) The present invention will be described in more detail according to an example 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 rod-shaped 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. A hole 12 is provided in the rear member 4, and within the hole 12 is an engaging member 13 which can come into contact with the inner wall of the hole 12 and the tapered portion 10 formed at the rear of the lead core locking member 11 due to its own weight. It is arranged so that it can be moved.
In the illustrated example, a plurality of plates (four pieces) are arranged as the engagement members 13 in the rear member 4, and one of the plates is caused by its own weight to connect with the inner wall of the hole 12 and the lead core locking member 1.
It is designed so that it can come into contact with the taper portion 10 of No. 1. Further, a C-shaped curved portion 14 is formed at the rear portion of the lead locking member 11, which is deformable when an excessive force exceeding the writing pressure is applied. The curved portion 14
Regardless of whether it is made of resin or metal, the curved portion 14 is deformed when excessive force is applied to it, and is able to return to its original shape with its own elasticity when the excessive force is removed.
This allows the lead core locking member 11 to be retracted in the longitudinal direction.

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

First, the supply of lead core will be explained.

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
The tapered portion 10, the engaging member 13, and the inner wall of the hole 12 create a wedge effect against the movement of the lead core locking member 11, 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 after completing appropriate writing and the tip of the lead lead L and lead guide tube 8 are moved away from the writing surface P, the force applied to the lead lead L and lead locking member 11 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, lead core locking member 11, lead core guide tube 8, and engaging member 13 other than their own weight, so the lead core guide tube 8 along with the lead core L is affected by its own weight. When the main body 1 moves forward and the rear part of the lead core guide tube 8 comes into contact with the inner front part of the tip member 2, the worn amount of the lead core L is supplied and its movement is stopped. 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 together with the engaging member 13 by its own weight, and stops its movement as the lead core guide tube 8 is stopped. (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 effect when an excessive force exceeding the writing pressure is applied to the lead guide tube 8 will be explained.

FIG. 4 shows a state in which an excessive force is applied to the lead core guide tube 8, and the lead core guide tube 8 and the lead core L tend to retreat with respect to the main body 1 due to the excessive force. At this time, the curved portion 14 formed on the lead core locking member 11 is deformed in response to the excessive force, and the lead core locking member 11 is contracted in the longitudinal direction, so that the lead core guide tube 8 and the lead core L are retreated. will be carried out. When the excessive force is released, the curved portion 14 returns to its original state by its own elasticity, and the lead core guide tube 8 and the lead core L also return to their original positions.

(Effects of the Invention) As described above, the present invention includes a main body, a lead core guide tube having a holding member that is arranged in the distal end of the main body so as to be freely forward and backward and that lightly holds the lead core inside, and a lead core locking member that is slidably disposed within the main body and capable of coming into contact with the rear end portion of the lead core held in the lead core guide tube; It consists of a tapered part of the lead locking member and an engaging member that can come into contact with the inner wall of the main body due to its own weight, and when writing pressure is applied to the lead lead, the lead locking member comes into contact with the lead lead toward the rear of the main body. In a sharp pencil that prevents movement and allows the lead locking member to move forward of the main body when writing pressure on the lead is released, writing can be performed at appropriate locations on the lead locking member. Since it is formed with a curved part that deforms when an excessive force exceeding the pressure is applied and can retract the lead locking member in the longitudinal direction, the supply for the wear of the lead lead L is reduced from the writing surface. This can be done sequentially by separating the tip of the sharp pencil, and therefore the lead can be fed without changing the gripping position of the sharp pencil when writing.
Further, since the lead lead guide tube only lightly holds the lead lead through the holding member, smooth retraction is possible and a smooth writing feeling can be obtained. Furthermore, even if an excessive force exceeding the writing pressure is applied to the lead guide tube due to falling or writing, the force is absorbed by the deformation of the curved part, so breakage of the lead lead can be prevented as much as possible. Various practical effects such as these can be achieved.

In the above embodiments, an example in which a wedge action was used as the engaging means was explained, but the present invention is not limited to such a structure, and it can be used when writing pressure is applied to the lead. A structure in which the lead locking member that comes into contact with the lead core does not move toward the rear of the main body, and the lead locking member can easily move toward the front of the main body when writing pressure on the lead lead is released. If so, various methods can be adopted.

[Brief explanation of the drawing]

Figure 1 shows an embodiment of the present invention, Figures 2-
FIG. 4 is an explanatory diagram of the operation 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,
14...Curved portion.

Claims (1)

[Scope of utility model registration request] a main body, a lead core guide tube having a holding member that is arranged in the distal end of the main body so as to be freely forward and backward and that lightly holds the lead core therein; and a rear end of the lead core whose front part is held by the lead core guide tube. a lead core locking member slidably disposed within the main body, and a lead core locking member movably disposed within the main body, and the tapered portion of the lead core locking member and the inner wall of the main body are brought into contact with each other by their own weight. It consists of an engaging member that can come into contact, and prevents the lead locking member that comes into contact with the lead lead from moving toward the rear of the main body when writing pressure is applied to the lead lead, and also prevents writing pressure from being applied to the lead lead. In a sharp pencil that allows the lead locking member to move forward of the main body when released, the lead locking member is deformed when an excessive force exceeding the writing pressure is applied to appropriate locations. A sharpening pencil characterized in that the lead core locking member is formed with a curved portion that can be retracted in the longitudinal direction.