Improvements in Electrical Switches.
Year: 1889

page_text: Date of Application, 6th Mar., 1889
Complete Specification Left, 6th Dec., 1889-Accepted 11th Jan., 1890
PROVISIONAL SPECIFICATION.
Improvements in Electrical Switches.
We, THOMAS PARKER of the firm of Elwell-Parker Limited, and EDMUND SCOTT
GUSTAVE REES, both of Commercial Road Wolverhampton, in the County of
Stafford, Electrical Engineers, do hereby declare the nature of this invention to be as
follows:-
This Invention relates to electrical switches and it has for its object to ensure a
good contact and a quick break of the circuit.
In a switch constructed according to these Improvements there are two diametri-
cally opposite fixed contacts, between which there is a stud on which a cross bar is
pivotted so as to be capable, when turned in one direction, of joining the fixed contacts
and thus closing the circuits, and when turned in the other direction, of disconnecting
the fixed contacts and thereby opening the circuit.
An inclined plane or inclined planes is or are employed in combination with the
cross bar in order to compel the movement of the cross bar along the stud during a
portion of its rotation. A spring preferably coiled around the stud is arranged so as
to tend to force the cross bar into the open position.
In opening the circuit, just as the ends of the cross bar are about to leave the fixed
contact bars or brushes, the spring and the inclined planes combine to force the ends
of the bar suddenly out of contact and thus make a quick break of the circuit.
The key by means of which the switch is operated, may be detachable and is formed
to centre on the stud with a projection on each side of the cross bar. These projec-
tions are so far apart as to allow considerable angular motion of the cross bar and of
the key independently of each other. Thus, when the sudden motion of the cross bar
takes place on the opening of the circuit, the cross bar can move freely without
encountering opposition and without necessitating an accelerated motion of the key.
Dated this 4th day of March A.D. 1889.
WILLIAM E. HEYS,
Agent for the Applicants...
COMPLETE SPECIFICATION.
Improvements in Electrical Switches.
We, THOMAS PARKER of the Electric Construction Corporation Limited, and
EDMUND SCOTT GUSTAVE REES, both of Commercial Road Wolverhampton in the
County of Stafford Electrical Engineers, 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 electrical switches and it has for its object to ensure a
good contact and a quick break of the circuit.
In a switch constructed according to these Improvements there are two diametri-
cally opposite fixed contacts between which there is a stud on which a cross bar
is pivoted so as to be capable of joining the fixed contacts and closing the circuit
when turned in one direction, and of disconnecting the contacts and thus opening
the circuit when turned in the other direction.
An inclined plane or inclined planes is or are employed in combination with the
cross bar in order to compel the cross bar to move along the stud during a portion
of its rotation. A spring, preferably coiled around the stud is arranged so as to tend
to force the cross bar into the open position.
The accompanying drawings illustrate in what manner our Improvements may be

page_text: carried into practical effect, and will be hereinafter referred to. In each of the
Figures similar parts are denoted by similar letters of reference.
Fig. 1 is a plan of one type of our Improved switch, shewing the circuit closed in
full lines and the circuit open in dotted lines. Fig. 2 is a cross section of the switch
shewn in Fig. 1 in the closed position, and Fig. 3 is a similar view of the switch in
the open position. Fig. 4 is a plan of a modified form of the switch with the cap
and key removed, and Fig. 5 is a cross section of the switch Fig. 4 with the cap and
key in place.
A A are the opposite fixed contacts to which the ends of the electric circuit are
connected in the usual manner. B is a central stud upon which the cross bar C is
mounted so as to be capable of movement in a vertical direction along the stud. The
cross bar is constructed so as to make contact with both the fixed contacts A A when
turned in the closed position. We prefer to make these contacts of the double brush
type as shewn in the drawings but any other suitable form of fixed contact may be
used.
DD are inclined planes which are formed either on the cross bar alone as in Figs. 4
and 5 or both on the cross bar and on on adjacent fixed part of the switch as shewn
in Figs. 2 and 3. On the stud and on the opposite side of the cross bar to that on
which the inclined planes are formed or arranged there is mounted a spiral spring E
which tends to force the cross bar along the stud in the direction of the inclined
planes. The effect of the inclined planes is to convert part of the rotary motion into
a vertical motion so that the resultant motion of the cross bar when operated by the
switch or handle is vertical and angular and the paths of the ends of the cross bar
will be spiral. This motion of the cross bar secures a good rubbing contact in opening
and closing the circuit.
As shown in Figs. 4 and 5 the inclined plane acts on a pin F which passes through
the stud B.
In opening the circuit, just as the ends of the cross bar are about to leave the fixed
contacts A A the spring and the inclined planes combine to force the ends of the bars
suddenly out of contact and thus make a very sudden break of the circuit.
The cross bar may be operated by a handle G as in Fig. 1 or by a key as in Fig. 4.
In either case that part of the key or handle which fits over the stud is provided with
two projections one on each side of the cross bar. These projections serve to give
motion to the cross bar but they are so far apart as to allow considerable angular
motion of the cross bar and of the handle or key independently of each other.
In opening the circuit the advanced part of one of the projections comes into
contact with the cross bar and pushes it forward until the point of last contact is
approached at this instant it is arranged that the further motion of the cross bar
shall be along the inclined plane and it is thus suddenly pushed by the spring
along and down the inclined plane. The distance between the projections on the
key or handle by means of which the cross bar is moved being considerable the
bar can advance freely without being stopped or impeded by the slower motion
of the handle or of the key.
;
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,
(1) An electric switch constructed and operated substantially as hereinbefore
described and as illustrated by the accompanying drawings.
(2) In an electric switch, the combination and arrangement with two fixed
contacts of a centrally pivoted cross bar working during a part of its rotation on
an inclined plane, a spring, and a handle or key; substantially as and for the
purpose hereinbefore described and as illustrated by the accompanying drawings.
Dated this 5th day of December A.D. 1889.
WILLIAM E. HEYS,
Agent for the Applicants.