JPH0116633Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a notch type sharpening pencil, and more specifically, a notch type sharpening pencil with a so-called centering length adjustment mechanism that allows the centering length to be adjusted with a single notch operation. It's about pencils.

Conventionally, as a knock-type sharp pencil with a centering length adjustment mechanism that allows the user to adjust the centering length according to the user's preference, the inner screw member that comes into contact with the rear end of the chuck ring is movable. There are known devices in which the member is moved forward and backward by rotating the member directly with a fingertip, and in which the internally threaded member is moved forward and backward by rotating the shaft tube or a part of the shaft tube. In both cases, the centering length can be adjusted by varying the distance between the front end of the chuck ring and the chuck ring movement prevention part formed inside the tip. There is an operational problem in that the tip must be removed each time, and although the latter has improved operability, the problem remains that the structure is complicated, and the centering length adjustment mechanism is still not included. There was still room for improvement regarding the mechanical pencil.

The present invention was developed in view of the above-mentioned problems, and it provides a new knock-type sharp pencil with a centering length adjustment mechanism that allows easy adjustment of the centering length and has a simple structure. It is on offer.

The present invention will be described in detail below based on embodiments shown in the accompanying drawings.

Reference numeral 1 denotes a barrel made of resin or the like. Inside the barrel 1, there is a core storage tube 3 to which a chuck 2, such as a three-split chuck, is connected to the front part, and an elastic body 4 made of a coil spring or the like. It is placed so that it is biased rearward.
5 has a core protection tube 6 arranged at the tip, and this core protection tube 6
This tip is made up of an elastic body 7 that imparts slight elasticity to the core at the rear of the tip, and this tip 5 is rotatably fixed to the tip of the shaft tube 1. A protrusion 1a is provided on the outer surface of the tip of the shaft cylinder 1, and a groove 5a corresponding to the protrusion 1a is provided on the rear inner surface of the tip 1, thereby serving as a rotating means. 8 is a chuck ring for fastening the chuck 2, and this chuck ring 8 is composed of a movable ring 9 and a fixed ring 10.
0 has a threaded portion 10a on the inner surface and a recess 10b on the outer surface that engages with a rib 1b formed on the inner surface of the tip of the shaft cylinder 1, and is movable only in the longitudinal direction. The movable ring 9 has a threaded part 9a formed on the outer surface of the fixed ring 10, and is screwed into the threaded part 10a of the fixed ring 10 in a freely expandable and contractable manner. Further, the front part of the movable ring 9 is formed with a flange part 9b having a non-circular cross section as shown in FIG.
The reason why the inner surface 5b of the movable ring 9 is made non-circular in cross section to correspond to this is to enable the movable ring 9 to move only in the longitudinal direction. Reference numeral 11 designates an inner stepped portion provided in the tip 5 to prevent the movable ring 9 from moving forward. In this example, a screw groove structure is adopted to make the chuck 8 expandable and retractable, but the screw portion 10a of the fixed ring 10 is made into a spiral groove, and the screw portion 9a of the movable ring 9 is replaced with a corresponding spiral groove. For example, a protrusion may be formed.

Next, the action will be explained.

When the tip 6 is fixed and only the barrel 1 is rotated, the rib 1b formed on the inner surface of the tip of the barrel 1
The fixing ring 10 that engages with will rotate together. Due to the rotation of the fixed ring 10, the movable ring 9 also tries to rotate in the same direction, but the rotation of the movable ring 9 is caused by the inner surface of the tip 5 having a non-circular cross section.
b and the outer surface of the flange 9b,
The movable ring 9 moves in the longitudinal direction along the threaded portion 10a of the fixed ring 10, and the total length of the chuck ring 8 becomes longer or shorter, and the distance L between the front end of the movable ring 9 and the inner stepped portion 11 (center (corresponding to the protrusion length) is shorter or longer. This operation can be similarly performed by fixing the barrel 1 and rotating the tip 6.

As described above, in the present invention, the moving distance of the chuck ring is changed by changing the total length of the chuck ring itself, which is made to be extendable and retractable by rotating the barrel or tip, so that the movement distance of the chuck ring can be changed by a single knob operation. It is excellent in that the centering length can be easily adjusted, the internal structure is not complicated, and the centering length can be adjusted easily and reliably.

In the embodiments, the present invention is shown as having a rear end notch type, but it can also be adopted as a side notch type, a side slide type, etc.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a longitudinal cross-sectional view of a main part, FIG. 2 is a cross-sectional view taken along the line A--A, and FIG. 3 is a cross-sectional view taken along the line B--B. 1...Main body, 2...Chick, 4...Elastic body,
5... Tip gold, 5b... Inner surface, 6... Core protection tube, 7
...Elastic body, 8...Chuck ring, 9...Movable ring, 9b...Brim portion, 10...Fixed ring.

Claims (1)

[Scope of utility model registration request] A chuck ring that fastens the chuck, which is urged backward by an elastic body, is brought into contact with the tip of the shaft cylinder, and a tip that is equipped with a core protection tube and an elastic body that holds the core is rotatable at the tip of the shaft cylinder. It gets stuck,
The chuck ring is composed of a movable ring and a fixed ring to be freely expandable and retractable, the fixed ring is disposed at the tip of the shaft cylinder so as to be movable only in the longitudinal direction, the outer surface of the flange of the movable ring is non-circular, and the inner surface of the tip is also formed. Correspondingly, this is a non-circular shape with a movable ring arranged so that it can move freely only in the longitudinal direction.