U.S. patent number 3,556,182 [Application Number 04/817,793] was granted by the patent office on 1971-01-19 for electric pencil sharpener.
This patent grant is currently assigned to Elm Industry Company, Limited. Invention is credited to Satoshi Tanigami.
United States Patent |
3,556,182 |
|
January 19, 1971 |
ELECTRIC PENCIL SHARPENER
Abstract
An electric pencil sharpener comprises a cylindrical cutter and
a rotary shaft having a pencil-feeding hole. A slider is disposed
at the rear inner portion of the hole and connected with a rod
extending through an axial hole in the rear portion of the shaft
and adapted to be moved in axial direction integrally with the
slider. The rear end of the rod projecting from the shaft is kept
in contact with a pivoted operation plate. As the plate is moved
backward by the point of pencil lead which is being sharpened, a
lamp on the arm of the plate is moved upward. The degree of
sharpness of the lead is indicated by the position of upwardly
moving light which can be inspected through windows in the front
panel.
Inventors: |
Satoshi Tanigami (Tokyo,
JP) |
Assignee: |
Elm Industry Company, Limited
(Tokyo, JP)
|
Family
ID: |
12367615 |
Appl.
No.: |
04/817,793 |
Filed: |
April 21, 1969 |
Foreign Application Priority Data
|
|
|
|
|
Apr 23, 1968 [JP] |
|
|
43/32754 |
|
Current U.S.
Class: |
144/28.5;
83/522.26; 340/680; 144/28.72 |
Current CPC
Class: |
B43L
23/02 (20130101); Y10T 83/865 (20150401) |
Current International
Class: |
B43L
23/00 (20060101); B43L 23/02 (20060101); B43l
023/06 () |
Field of
Search: |
;144/28,28.1,28.3,28.4,28.5,28.6,28.7,28.72 ;83/522 ;340/265,282
;77/5 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Andrew R. Juhasz
Assistant Examiner: James F. Coan
Attorney, Agent or Firm: George B. Oujevolk
Claims
1. In an electric pencil sharpener having a rotary shaft provided
with a pencil-feeding hole in conical form and a cylindrical cutter
supported on said rotary shaft and adapted to be rotated orbitally
and on its own axis, said cutter being disposed along the slanting
surface of the pencil-feeding hole, a structure comprising a slider
disposed in the inner rear portion of said pencil-feeding hole and
adapted to be freely moved along the axis of said rotary shaft, a
rod extending through an axial hole in the rear portion of said
rotary shaft and having a forward end connected to said slider and
a rear end projecting backward from said rotary shaft so as to move
integrally with said slider in the axial direction, an operation
plate kept in abutting contact with the rear end of said rod all
the time due to the weight of an arm supporting an indication lamp
to be moved up and down, and windows provided in the front panel of
a casing for inspecting from the front of the casing the indication
lamp attached to the forward end of the arm which is integral
2. The electric pencil sharpener as claimed in claim 1 wherein said
windows are arranged in an appropriate number in vertical row along
the direction of upward and downward movement of said indication
lamp so as to provide stagewise indications of the position of said
lamp, each of said windows
3. The electric pencil sharpener as claimed in claim 1 wherein
along the row of said windows are provided marks for indicating the
degree of sharpness of the pencil lead.
Description
The present invention relates to an electric pencil sharpener, more
particularly to a device for indicating the degree of sharpness of
the lead sharpened to see to what extent the pencil point has been
sharpened while it is being sharpened.
In order to indicate the sharpness of the lead in an electric
pencil sharpener, a certain type of device has been proposed in
which a lamp for indicating the sharpness is turned on and off.
However, in indicating the degree of sharpness of the lead
stagewise as in two or three stages with this type of device, there
is a need to provide a required number of indication lamps in
accordance with the number of the stages and contacts to open or
close the circuits of the indicating lamps, so that the structure
becomes inevitably complicated. The electric sharpener is therefore
quite disadvantageous in that the more complex the structure
becomes, the more likely it is that the sharpener is susceptible to
troubles, since the sharpener is rotated at an extremely high
speed.
An object of the present invention is to eliminate above-mentioned
disadvantages of conventional electric pencil sharpeners.
Another object of the present invention is to provide a device to
be used in an electric pencil sharpener for indicating the degree
of sharpness of the lead which is simple in structure and free from
troubles.
Still another object of the present invention is to enable a single
indication lamp to provide stagewise indications in two, three or
more stages of sharpness of the lead which is being sharpened so
that useless over-sharpening of the pencil may be precluded.
The features of the present invention will become apparent in an
embodiment shown in the accompanying drawings, in which:
FIG. 1 is a perspective view of an electric pencil sharpener in
accordance with the present invention, part of the casing being
broken away to show the interior structure;
FIG. 2 is a front view of FIG. 1 showing a pencil feeding portion
and an indicator of sharpness of the lead which are provided in the
front panel of the casing;
FIG. 3 is a side elevation in section taken along the line III -III
in FIG. 2; and
FIG. 4 is an electrical circuit diagram for driving a motor and
turning on an indication lamp.
As shown in the drawings, the casing of an electric pencil
sharpener comprises two upper and lower portions 1 and 2 which are
integrally joined together by means of screws (not shown). In the
front of the upper portion 1 is provided a pencil holder 4 having a
pencil-feeding inlet 3 and in the lower portion, a suitable number
of support legs 5 made of rubber or the like attached to the under
surface. In the front of the lower portion 2 is mounted a
drawerlike receptacle 6 for chips which is adapted to be pulled
out. In the interior of the casing is fixed a frame 7 which is
integral with the lower portion 2 and to which is fixedly secured,
by means of bolts (not shown), a bracket 8 for supporting a motor M
and an operation mechanism to be later described.
A rotary shaft 10 formed with a pencil feeding hole 9 in conical
shape is rotatably supported on the bracket 8. A follower gear 11
secured to the rotary shaft 10 at the rear end meshes with a pinion
12 keyed to the shaft of a motor M and through this meshing
engagement the rotary shaft is driven. The pencil feeding hole 9 in
the rotary shaft 10 is coaxial with the pencil-feeding inlet 3 of
the pencil holder 4 and it is also coaxially disposed with the axis
of rotation of the rotary shaft 10. Provided inside the front panel
13 of the bracket 8 is a sliding member 14 which is adapted to be
pushed in the radial direction upon insertion of the pencil to
close the switch of motor M.
The rotary shaft 10 further supports a cylindrical cutter 15 by an
axis 16 in rotatably manner while allowing the same to orbitally
rotate around the axis of the shaft 10, the cylindrical cutter 15
being provided with screwlike cutting edges exposed to the slanting
surface of the conical hole 9 for receiving the pencil. Integrally
formed with the cylindrical cutter 15 at its tail end is a
planetary gear 17 which is in meshing engagement with an internal
gears 18 fixed to the bracket 8, so that the cylindrical cutter 15,
while being orbitally rotated, is rotated on its own axis to cut
the forward end portion of the pencil pushed into the conical
pencil feeding hole 9 and to sharpen the lead. Since the rotary
shaft 10 rotates while supporting the cylindrical cutter 15, the
rotary shaft 10 is provided with a balancer to ensure rotation in
balanced condition. Designated at 20 is a cord connected to a power
source.
When the pencil is pushed in through a pencil-feeding inlet 3 of
the pencil holder 4, the sliding member 14 turns on the switch of
motor M, and upon the rotary shaft 10 being brought into high speed
rotation of the cylindrical cutter 15 is rotated orbitally while
being driven on its own axis to sharpen the pencil point in already
known manner.
In addition to the foregoing structure, in the most inner portion
of the conical pencil-feeding hole 9 of the rotary shaft 10 there
is disposed a slider 21 which is free to move forward and backward
along the axis of the rotary shaft 10. This slider 21 is attached
to the rotary shaft 10 with a portion thereof engaged with a guide
groove 22 formed in the rotary shaft 10 and adapted to be pushed
backward toward the rear of rotary shaft 10 by the point of pencil
lead which has been sharpened with the cylindrical cutter 15.
It will be seen in the drawings that in the backward portion of the
rotary shaft 10 is formed an axial hole 23, the shaft thus being
formed as a hollow cylinder. The back of the slider 21 is connected
with a front end of a rod 24 which extends through the hole 23 so
as to move freely in the axial direction, with the rear end of the
rod backwardly projected out of the rotary shaft 10. Behind the
rotary shaft 10 is provided an operation plate 25 to be brought
into abutting contact with the tail end of the rod 24. The lower
end of the operation plate 25 is pivoted on a shaft 26 which is
transversely supported on the bracket 8, the plate thereby being
adapted to be pivotally moved back and forth on the shaft 26.
Integrally formed with the operation plate 25 at a side portion
thereof is an arm 27 extending forward and provided with an
indicating lamp L at its forward end. As shown in FIG. 4, the
indication lamp L IS INSERTED IN THE CIRCUIT OF THE MOTOR M in
parallel therewith. The lamp is so adapted that it is turned on
simultaneously with the closure of the switch S.
When the slider 21 is pushed backward by the point of pencil lead,
the operation plate 25 is pivoted backward with the end of the arm
27 moved upward. That is to say, the indication lamp L is raised in
accordance with the degree of sharpness of the pencil lead. The
upward and downward movement of the arm 27 is guided by a vertical
groove 28 formed beside the bracket 8.
In the front panel of the upper portion 1 of the casing at a
portion corresponding to the position of the upward and downward
movement of the indication lamp L, a suitable number of windows 29
are arranged in vertical row. To the windows 29 are fitted
transparent plates 30 colored in appropriate colors as in red,
yellow, blue, etc. Accordingly, as the indication lamp L is brought
upwards, the light of indication lamp L, as it is moved upwards
from the lowermost position, can be observed through the windows 29
in the front panel of the electric pencil sharpener. Thus, the
sharpness of the lead can be inspected. In order to provide more
distinct indication, mark 31 showing the sharpness of lead is
printed beside the windows 29.
It will be understood from the foregoing description that the
sharpness indicator is very simple in structure and is very simply
in structure and is well fit for high speed rotation of the
electric pencil sharpener. The indicator is therefore perfectly
free from troubles and there is no need to employ more than one
indication lamp. Furthermore, the light passing through the colored
transparent plates serves to provide better indication of the lead
sharpness.
When the pencil which has been sharpened to a desired degree is
taken out of the feeding hole 9, the sliding member 14 projects
into the feeding inlet 3 to open the switch S for the motor M and
indication lamp L. The motor M is thus brought to a halt and the
indication lamp is turned off. Due to the weight of the arm 27, the
operation plate 25 is pivotally moved forward and the indication
lamp is thereby lowered. At the same time, the rod 24 is pushed to
move the slider 21 forward along the axis of the rotary shaft 10.
The movement of the slider is guided by the groove 22.
* * * * *