Improvements in Electrical Switches.
Year: 1893

page_text: Date of Application, 17th May, 1893
Complete Specification Left, 24th Jan., 1894-Accepted, 3rd Mar., 1894
PROVISIONAL SPECIFICATION:
Improvements in Electrical Switches.
We RICHARD GEORGE ÉVERED, Director of Evered and Company Limited
of Barnet Works Birmingham in the County of Warwick Manufacturers and
ALFRED WATSON Associate of the Institution of Electrical Engineers Foreman
of Works at Barnet Works, Birmingham aforesaid do hereby declare the nature of
this invention to be as follows:-
Our improvements consist in constructing and arranging in the manner herein-
after explained the parts of electrical switches. Switches made according to our
invention are especially adapted for use with electrical incandescent lamps and we
will describe our invention as applied to an electrical incandescent lamp.
To one of the fixed terminals in the holder of the lamp (by connecting or dis-
connecting which terminals the current is established and interrupted) a lever is
When moved in
attached the said lever turning upon the terminal as a fulcrum.
one direction the end of the long arm of the said lever is brought under and presses
against a spring arm fixed on the end of the other terminal, which we will call the
second terminal, and by reversing the motion of the lever the long arm of the lever is
disconnected with the fixed terminal. When the terminals are in an electric
circuit the said circuit is closed when the lever is in the former position and broken
when the lever is in the latter position. A spring pressing on the said lever forces
it when at liberty to move out of contact with the second terminal. The forward
motion of the long arm of the lever (that is the motion by which the current is
closed) is effected in the following manner. The short arm of the said lever is
nearly at right angles to the long arm and it is by pressure effected as hereinafter
described on the said arm that the long arm is made to advance and close the
circuit. An annular collar turning loosely on the body of the holder has a series
of radial notches on its inner edge. The terminals are situated within the collar
and the internal diameter of the collar is such that when any of its unnotched parts
are presented to the short arm of the lever they press upon the said short arm so aя
to give the long arm its forward motion and close the circuit. When by turning
the said collar one of the notches in its inner edge is brought opposite the short
arm of the lever the said short arm snaps into the said notch by the action of the
lever spring and the long arm of the lever is suddenly withdrawn from the second
terminal and the circuit is suddenly broken. Thus by turning the said collar the
circuit is opened and closed during one rotation as many times as there are notches
in the collar. There is little or no danger in the careless turning of the collar as
the operator by the lighting up or extinguishing of the lamp at once knows when
he has turned the collar into the required position.
Dated this 17th dow of Mov 1893
W. T. WHITEMAN,
Agent for the Applicants.

page_text: Improvements in Electrical Switches.
We RICHARD George Evered. Director of Evered and Company Limited,
of Barnet Works Birmingham in the County of Warwick, Manufacturers, and
ALFRED WATSON, Associate of the Institution of Electrical Engineers, Foreman
of Works at Barnet Works, Birmingham, aforesaid do hereby declare the nature of
the said invention and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement :-
Our improvements consist in constructing and arranging in the manner herein-
after explained the parts of electrical switches. Switches made. according to our
invention are especially adapted for use with electrical incandescent lamps and we
will describe our invention as applied to an electrical incandescent lamp.
To one of the fixed terminals in the holder of the lamp (by connecting or dis-
connecting which terminals the current is established and interrupted) a lever is
attached, the said lever turning upon the terminal as a fulcrum. When moved in
one direction the end of the long arm of the said lever is brought under and presses
against a spring arm fixed on the end of the other terminal which we will call the
second terminal, and by reversing the motion of the lever the long arm of the lever
is disconnected from the fixed terminal. When the terminals are in an electric
circuit, the said circuit is closed when the lever is in the former position and
broken when the lever is in the latter position. A spring pressing on the said
lever forces it when at liberty to move, out of contact with the second terminal.
The forward motion of the long arm of the lever (that is the motion by which the
current is closed) is effected by pressure on the short arm in the following manner.
An annular collar turning loosely on the body of the holder has a series of radial
notches in its inner edge. The terminals are situated within the collar and the
internal diameter of the collar is such that when any of its unnotched parts are
presented to the short arm of the lever they press upon the said short arm so as to
give the long arm its forward motion and close the circuit. When by turning the
said collar one of the notches in its inner edge is brought opposite the short arm of
the lever the said short arm snaps into the said notch by the action of the lever
spring and the long arm of the lever is suddenly withdrawn from the second
terminal and the circuit is suddenly broken. Thus, by turning the said collar the
circuit is opened and closed during one rotation as many times as there are notches
in the collar.
.
Figure 1 of the accompanying drawing represents partly in elevation and partly
in vertical section an electrical incandescent lamp holder with which an electrical
switch constructed according to our invention is combined; such combined lamp
holders and switches are known in commerce as electrical switch lamp holders;
Figures 2 and 3 represent cross sections of the same taken on the line A A
Figure 1, the circuit in the switch being represented closed in Figure 2 and open
in Figure 3;
Figure 4 represents in vertical section the insulator of the switch lamp holder
and the parts carried by it for the purpose of showing the connection between the
lever of the switch and one of the spring plunger contacts of the holder and
Figure 5 represents in elevation and plan the lever of the switch detached.
The same letters of reference indicate the same parts in the several figures of
the drawing.
b is the electrical incandescent lamp holder carrying the insulator a and spring
plunger contacts 1, m (see Figure 4). On the top of the insulator a the fixed
terminals of the switch are arranged. Turning on the fixed terminal is the
lever e, e. The fixed terminal consists of a spring fork shaped arm between the
branches of which the long arm e' of the lever on the other terminal c³ passes when

page_text: turned into the position represented in Figures 1 and 2. By turning the lever e, e
in one direction its long arm e³ is pressed into contact with the terminalf thereby
completing the circuit in the switch as hereinafter explained and by reversing the
motion of the lever e, e³ the long arm e³ is disconnected from the fixed terminal f
and the circuit in the switch is broken. Thus by turning the lever e, e² in one
or other direction contact between the fixed terminals c², is made or broken and
the electric circuit in the switch closed or opened as hereinafter described.
g
The motions of the lever e, e² on the terminal care effected in the following
manner. Situated and turning loosely on the body of the holder b is a collar
milled externally and having in its inuer edge three equidistant notches g*. Coiled
on the terminal is a wire spring the free end 72 of which bears against a
projection on the short arm e of the lever, the other free end of the said
spring bearing against a fixed projection on the plate c carrying-the terminal c².
When by turning the collar g in the direction of the arrow Figure 3 one of the
notches is presented to the short arm e of the lever the said short arm snaps into
the said notch g2 by the action of the spring and the long arm e² of the lever is
suddenly withdrawn from the terminal as represented in Figure 3 and the
electrical circuit in the switch is broken. By bringing the collar into such a
position that one of the unnotched parts is brought to bear against and push
forward the short arme of the lever the long arm e² of the said lever is pressed
into contact with the fixed terminal fand the circuit is completed.
Although we have described and represented the collar gas having three
equidistint notches g² in its inner edge yet the said collar may have only one or
two or more than three notches, the circuit in the lamp being opened and closed on
the rotation of the collar through a complete rotation as many times as there are
notches in the collar.
manner.
'
The conducting wires are connected to the switch lamp holder in the following
One of the conducting wires passes down the hole p in the insulator a
and is connected to the spring plunger contact l. The other conducting wire passes
down the hole n in the insulator a and is connected to the terminalf through the
metallic piece and screw d (see Figure 1). Assuming a lamp to be in position in
the holder, the terminals, of the switch connected and the current to be passing
through the lamp, the said current passes down the spring plunger contact / through
the carbon filament of the lamp, up the other spring plunger contact m to the
terminal then through the lever e, e² of the switch to the other terminal/
connected to the other conducting wire as hereinbefore described.
Figures 6, 7, 8, 9, 10 and 11 of the accompanying drawing represent our improve-
ments applied to an ordinary electrical switch, that is, a switch independent of an
incandescent lamp holder.
Figure 6 represents the said switch partly in elevation and partly in section;
Figure 7 represents in elevation a portion of the same, the said elevation being
taken at right angles to the elevation Figure 6. Figures 8 and 9 represent plans
of the switch with the outer cover or case removed; Figure 10 represents in
elevation, and plan the lever of the switch detached. Figure 11 represents a
modification of the switch as hereinafter described.
k is the case or outer cover of the switch having at opposite points holes or
depressions for taking upon pins or studs 93, 93 on the upper side of the collar g.
The rotation of the collar y is effected by turning the case or cover k. The case
or cover k may however be fixed, the collar g in this case being by preference
made of a slightly greater diameter than the case or cover and having its outer
edge milled to facilitate the rotation of the collar. As the action of the switch
Figures 6, 7, 8, 9 and 10 is essentially the same as that described and represented
in combination with the electrical incandescent lamp holder Figures 1, 2, 3 and 4
and as corresponding parts in the two switches are marked with the same letters of
reference, we do not think it necessary further to describe the same.
Where thought desirable the plate c of the terminal e³ may be prolonged as
represented in the modification Figure 11 and brought under the end of the

page_text: terminal which in this case consists of a single projecting arm.
The long-arm e
of the lever in this modification is cranked at its end and is so arranged that when
moved into contact with the terminal the circuit is completed by the cranked end
of the long arm e² of the lever connecting the terminalf with the part of the
plate e immediately under it.
Having now particularly described and ascertained the nature of our invention
and in what manner the same is to be performed we declare that we claim as our
invention of "Improvements in Electrical Switches ";-
In electrical switches the combination of a spring lever of the construction
described with an internally notched collar for operating the said spring lever for
making or breaking contact in the switch, the parts being arranged, combined and
operated substantially in the manner hereinbefore described and illustrated in the
accompanying drawing.
Dated the Twenty-second day of January 1894.
RICHARD GEORGE EVERED.
ALFRED WATSON.