Improvements in Electric Switches or Circuit Breakers.
Year: 1894

page_text: Date of Application, 9th Oct., 1894-Accepted, 10th Nov., 1894
COMPLETE SPECIFICATION.
Improvements in Electric Switches or Circuit Breakers.
We, FRANK STEVENS, Mechanic, of 3840 Lynwood Street, and ROBERT
RODWELL KESTEVEN, Merchant, of 407 South 13th Street, both of Philadelphia,
in the County of Philadelphia, 'State of Pennsylvania, United States of America,
do hereby declare the nature of this invention and in what manner the same is to
be performed to be particularly described and ascertained in and by the following
statement:-
This invention relates to electric switches or circuit breakers; and it has for its
object to provide a simple, cheap and effective switch, which may be applied and
used in a house or room without disfigurement, and which shall insure the complete
making or breaking of the circuit when operated, and to these ends my invention
consists in a switch embodying the features of construction, arrangement and mode
of operation substantially hereinafter more particularly pointed out.
Referring to the accompanying drawing wherein I have shown the preferred
embodiment of my invention:
Fig. 1 is a perspective view of the complete switch;;
Fig. 2 is a side view showing the switch open;
Fig. 3 is a part sectional view showing the mode of operating the switch;
and
Fig. 4 is a vertical rear section of the switch.
As above indicated the switch is intended more particularly to be applied to a
house, desk or wall where it shall be exposed to the smallest extent and interfere
the least therewith, and to this end it is adapted to be inserted in a proper mortise
or recess in the wall or desk leaving only the face plate with the push buttons
exposed.
Thus, in the drawings A represents the face plate which may be of
any suitable
material, preferably capable of a high finish, as metal, and it may be provided with
openings a, whereby it may be secured in position. Extending through the face
plate are the push buttons B, B, and these are fitted in openings in the face plate,
the edges of which may be reamed or chamfered as shown. Secured to the face
plate is a frame C which is preferably of insulating material and which may be
rectangular in shape and is adapted to support the terminals of an electric circuit.
In the present instance I have shown the spring contacts D D¹ as secured to the side
of the frame by screws, which may also be binding screws for the wires or
conductors.
Carried by the frame C or face plate A is a support E to which is pivoted a
rocking arm or lever F.
H is a contact lever pivoted as at G to the frame C and having its free end
adapted to make and break circuit with the contacts D!.
I is a spring connected at one end as ath to the lever H at or near its free end,.
and at its other end to the lever F, as at f. I prefer to connect the spring with a
carried by the lever F and projecting into a slot has shown in the drawing
più
TDQJ1

page_text: for the purpose hereinafter described. The pin and slot connection may however
be omitted. For a double pole switch the lever F may be provided on one end
with contacts to make and break circuit with the contacts D as shown.
J.
11
"
The push buttons B B' are mounted in sockets in the frame and provided with
springs J, which normally press them outward, and they are provided with
stems K, K', passing through openings in the frame and carrying fingers or
toes L, L'. These fingers or toes are preferably shaped and serve the purpose
of preventing the push buttons slipping out of their sockets and of operating the
rocking lever F in the manner hereinafter set forth.
The operation of the device is as follows:
Supposing the parts to be in the position shown in Fig. 3 with the lever H thrown
to close the circuit through the contacts D¹. If now the push button B, which may
be marked "off," or made black as shown, to distinguish it from the other button B¹
marked "on," or made white, is pushed in, it will act through the toe L upon the
end of the lever F and will rock the lever on its fulcrum. As the lever F is rocked
its pin is moved in the slot on the lever H until it reaches the end of the slot
and acts upon the lever H. The movement of the lever F causes the pin f to act
positively upon the lever H and thus rocks it upon its fulcrum so as to move its end
in the contacts D'. During this movement however the point of connection of the
spring 1 with the lever F is moved above the line connecting the fulcrum of the
lever H and the point of connection hand consequently the tension of the spring
acts to suddenly move the lever 'H and to snap its end out of contact with or
away from the contacts D', thus breaking the circuit and throwing the parts into
the position shown in Fig. 2.
The object of employing the pin fand slot is that the positive pressure of the
pin on the lever H acts to move the lever H, for a part at least of its movement,
so that the tension of the spring I is not alone relied upon to move the lever and
break the circuit. There is considerable friction to be overcome between the
contacts and the lever in breaking the circuit and by employing the pin fand
sloth, or an equivalent construction, so that a positive action of the lever F on
the lever H is obtained to overcome that friction, either partially or wholly, the
work to be performed by the spring is decreased, and at the same time the quick
action of the spring is obtained to snap the lever open and prevent arcing.
If desired, however, the pin and slot construction may be omitted and the spring I
may be relied upon alone to operate the lever H; and so far as my invention is
concerned with the employment of the spring pressed push buttons B, 13¹ for
actuating the switch, it is immaterial whether this construction be employed or not.
In closing the switch the button B is pushed in, and the toe L" thereof acting on
the other end of the lever F rocks it and causes the pin f to act upon the lever H
and close it the spring I assisting in the closing. It will be seen that in whichever
position the parts are left either with the circuit closed or broken the tendency of
the spring is to maintain the pivoted and the rocking levers in that position, until
forcibly made to assume a contrary position, and when the circuit is made or broken
it is instantaneously accomplished, avoiding the danger of arcing, and the contact
lever sliding over the contact the parts are kept bright and afford good electric
communication. In order to prevent the push buttons turning in their sockets a
feather may be arranged on the side of the extension which operates in a recess in
the socket and maintains the toes L. in proper position to impinge upon the rocking
lever H. For a double pole switch in which the end of the lever makes contact
with contacts D, it is apparent that the movements of the lever F in making and
breaking the circuit take place at the same time with the movements of the
lever H.
The invention is thus applicable to either a single or double pole switch.
The frame C and operative parts may be enclosed in an enveloping cover shown

page_text: Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is:
The electric switch or circuit breaker constructed and operating substantially as
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :
The electric switch or circuit breaker constructed and operating substantially as
described.
Da of Contambor A.D 1804
FRANK STEVENS.
ROBERT RODWELL KESTEVEN.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicants.