Coating implements with material supply – Solid material for rubbing contact or support therefor – Including means to advance material
Patent
1992-11-03
1994-10-11
DeMille, Danton D.
Coating implements with material supply
Solid material for rubbing contact or support therefor
Including means to advance material
401 82, 401 94, 401115, B43K 2116, B43K 2902
Patent
active
053541413
DESCRIPTION:
BRIEF SUMMARY
BACLGRPIMD OF THE INVENTION
1. Field of the Invention
The present invention relates to a mechanical pencil with a shaking type lead-feeding mechanism for forwardly moving a lead holding chuck with an inertial force of a weight upon shaking a cylindrical casing so as to feed a pencil lead.
2. Background Art
In the above-mentioned type of mechanical pencil, a weight is disposed in a cylindrical casing thereof in such a way that the weight reciprocally is movable in the longitudinal direction of the cylindrical casing. When the casing is shaken in the longitudinal direction thereof, the weight is quickly moved toward a writing point. With an inertial force of the weight, a lead holding chuck is moved toward the writing point against the resilient force of a spring. Thus, the pencil lead is fed. In this type of mechanical pencil, a shoulder portion with which the weight collides and comes in contact is disposed on the chuck side. In addition, this mechanical pencil is provided with a stopper which prevents the weight from dropping out of the rear end of the cylindrical casing upon a rearward motion of the weight due to a reaction to the forward motion thereof. This stopper is formed as an outer collar on a cylindrical lead reservoir connected to the rear portion of the lead holding chuck. The stopper limits the rearward movement of the ring-shaped weight slidably mounted on the outer surface of the lead reservoir.
However, in the conventional mechanical pencil with the shaking type lead-feeding mechanism, whenever the weight moves rearward and comes in contact with the stopper, the lead reservoir also moves rearward due to a rearward shock applied thereto. Thus, the chuck also moves rearward. At this time, the chuck is closed instantaneously by a tightening ring. As a result, the pencil lead in the chuck is sometimes damaged or broken thereby.
Moreover, this type of mechanical pencil is also provided with a knock member at the rear end of the cylindrical casing so as to supply pencil leads and feed the pencil lead being chucked. When a rubber eraser is mounted on the knock member, and the eraser is used, the chuck is moved forward whereby the pencil lead is fed. To solve this problem, the knock member should be urged by a spring with a relatively strong resilient force in the longitudinally rearward direction of the casing.
However, this mechanical pencil has a large number of parts. In addition, since the mechanical pencil should be assembled in a state where the spring is compressed, productivity in the manufacture of the mechanical pencil is low, whereby the manufacturing cost thereof is high. Moreover, when the knock member is to be knocked to feed the lead, the spring with the relatively strong resilient force should be compressed by the knock member. Therefore, the finger of the user for knocking the knock member sometimes hurts. On the other hand, when the eraser is part of the knock member, if a short eraser floats from the bottom of the hole of an eraser holder, the eraser may sink into the eraser holder.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a mechanical pencil with a shaking type lead-feeding mechanism in which the rearward motion of the weight neither causes the chuck to damage or break a pencil lead therein, nor requires a strong force for the operation of the knock member.
To achieve this object, a mechanical pencil having a shaking type lead-feeding mechanism, according to the present invention, comprises a cylindrical casing having a front end portion for writing and a rear end portion, a lead holding chuck disposed in the cylindrical casing adjacent to the front end portion, a lead reservoir connected to a rear portion of the lead holding chuck for storing a pencil lead to be fed to the chuck, a weight reciprocally movable in a longitudinal direction of the cylindrical casing along the lead reservoir, for applying an inertial force to the chuck when the cylindrical casing is shaken, the inertial force causing the chuck to feed the pencil lead, and a knoc
REFERENCES:
patent: 4205924 (1980-06-01), Sumita
patent: 4352580 (1982-10-01), Ando
patent: 4619539 (1986-10-01), Kageyama
patent: 4929107 (1990-05-01), Kageyama et al.
DeMille Danton D.
Pilot Precision Kabushiki Kaisha
LandOfFree
Mechanical pencil with shaking type lead-feeding mechanism does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Mechanical pencil with shaking type lead-feeding mechanism, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Mechanical pencil with shaking type lead-feeding mechanism will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1654410