JP2002166692A - Retractable mechanical pencil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a retractable mechanical pencil, in which the bending between a chuck 1 and a lead tank 2 is solved and, at the same time, the assembling properties of which is improved. SOLUTION: An elastic body is externally fitted onto a connector 6. By frictionally fitting the elastic body onto the inner surface of a barrel 14, the connector 6 is detachably provided in the barrel 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a knock mechanical pencil for mounting a mechanism comprising a chuck, a fastener, a washer, a spring and a connector at the front of a barrel.

[0002]

2. Description of the Related Art In a conventional knock mechanical pencil, a mechanical portion is attached by sandwiching a washer between a front end of a barrel and a step portion of a base.

[0003]

Therefore, in the conventional knock mechanical pencil, when the inner surface of the front part of the barrel is made to have a large diameter, between the core tank connected to the chuck and the inner surface of the barrel. When a gap is generated and the lead tank is pressed forward with a strong force to feed the lead, the lead may be bent at a connecting portion between the chuck and the lead tank, causing a malfunction such as malfunction or failure of the lead to be drawn.

When the front inner surface of the barrel is set slightly larger in diameter than the core tank, a spare core is stored in the core tank and an eraser support or knob is attached to the rear of the core tank. Since the core tank cannot be inserted from the front of the barrel, there is a problem that productivity is significantly impaired.

An object of the present invention is to provide a knock mechanical pencil that solves the above-mentioned problems.

[0006]

SUMMARY OF THE INVENTION The present invention comprises a chuck,
A core tank connected to the rear of the chuck, a fastener externally fitted to the head of the chuck, a fastener for fastening the chuck, a washer for receiving the fastener, and a spring for urging the chuck rearward in the longitudinal direction. A coupling for receiving the washer, a shaft cylinder provided with the coupling at the front portion, and a base detachably attached to the front portion of the shaft cylinder. The connecting member is detachably provided to the shaft cylinder by frictionally fitting the body to the inner surface of the shaft cylinder.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A knock mechanical pencil according to the present invention will be described below with reference to FIGS. First, chuck 1
A core tank 2 made of a synthetic resin pipe connected to the chuck 1, a fastener 3 fitted externally to the head of the chuck 1, and
A mechanical part of the knock mechanical pencil is constituted by a washer 4 for receiving the fastener 3 and a spring 5 stretched between the washer 4 and the core tank 2.

A connecting member 6 having an inner hole 6A slightly larger in diameter than the outer diameter of the core tank 2 is fitted to the core tank 2 and a rubber O-ring is inserted into a concave groove 6B of the connecting member 6. 7 is externally fitted to the state shown in FIG.

Further, after storing the spare core 8 in the core tank 2, an eraser support 9 is connected to the rear part of the core tank 2. An eraser 10 is provided inside the rear of the eraser support 9, and a knob 11 for covering the eraser 10 is detachably fitted to the outside of the rear of the eraser support 9.

The crown 12 has a clip 13 integrally formed on the upper side and a small diameter portion 12A formed on the front. A protrusion 12B is formed on the outer peripheral surface of the small-diameter portion 12A immediately below the clip 13, and a protrusion 12C extending in the longitudinal direction is formed on the outer peripheral surface opposite to the protrusion 12B. Further, opening windows 12D extending in the longitudinal direction are formed on both sides of the small-diameter portion 12A so as to face each other, and the small-diameter portion 12A where the projection 12B is located is configured to be elastically deformable as appropriate.

The crown 12 has a small-diameter portion 12A inserted from the rear end of the barrel 14, and a projection 12C of the crown 12 is fitted into a keyway 14A of the barrel 14. In addition, the cap 12
When the small diameter portion 12A is inserted, the projection 12B of the crown 12 is fitted into the locking window 14B of the barrel 14, and the crown 12 is fixed to the barrel 14.

The mechanical section of the knock mechanical pencil,
The connecting member 6, the eraser support 9 and the knob 11 are inserted from the front of the barrel 14, the O-ring 7 of the connecting member 6 is frictionally fitted to the inner surface of the barrel 14, and the connecting member 6 is detachable from the barrel 14. Provided.

Accordingly, since the core tank 2 is guided by the inner hole 6A of the connecting member 6, there is no fear of bending at the connecting portion between the chuck 1 and the core tank 2. In addition, the eraser support 9 and the knob are attached to the core tank 2. 11 is provided, and then the mechanism is replaced with the barrel 1
4 can be easily assembled.

If the mechanical part fails, the barrel 1
4 can be easily replaced by removing the connecting tool 6.

Further, the front small diameter portion 14C of the barrel 14 has
A non-slip grip 15 made of a thermoplastic elastomer or silicone rubber is attached. This barrel 14
The washer 4 is clamped between the front end of the connecting tool 6 and the inner step 16A of the base 16 by screwing the base 16 into the front part of the base.

In addition, a core holder 17 made of an elastic material such as rubber for holding the core 8 with an appropriate force is incorporated in the base 16.

[0017]

In the above-described knock mechanical pencil according to the present invention, since the lead tank is guided by the inner hole of the connecting tool, there is no fear of bending at the connecting portion between the chuck and the lead tank. After the eraser support and the knob are attached to the mechanism unit, the mechanism can be inserted into the shaft cylinder, so that an effect that the assembly can be easily performed can be obtained.

Further, when the mechanical part breaks down, the effect that the mechanical part can be easily replaced by removing the connecting member from the barrel is also provided.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a knock mechanical pencil according to the present invention.

FIG. 2 is an enlarged sectional view taken along line AA of FIG.

FIG. 3 is an enlarged sectional view showing a connecting tool and an O-ring.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Chuck 2 Core tank 3 Fastener 4 Washer 5 Spring 6 Connector 7 O-ring 14 Shaft barrel 16 Base

Claims (2)

[Claims] 1. A chuck, a core tank connected to a rear portion of the chuck, a fastener externally fitted to the head of the chuck, a fastener for fastening the chuck, a washer for receiving the fastener, and a longitudinal rearward of the chuck. A spring for biasing the shaft, a coupling for receiving the washer, a shaft cylinder having the coupling at the front thereof, and a base detachably attached to the front of the shaft cylinder. A knock-type mechanical pencil, wherein a body is externally fitted, the elastic body is frictionally fitted to an inner surface of the barrel, and a connecting tool is detachably provided on the barrel. 2. The knock mechanical pencil according to claim 1, wherein the elastic body is constituted by an O-ring made of rubber.