Improvements in Electric Switches.
Year: 1896

page_text: Date of Application, 2nd Nov., 1896
Complete Specification Left. 3rd Aug, 1897-Accepted, 4th Sept., 1897
PROVISIONAL SPECIFICATION.
Improvements in Electric Switches.
MORTON BLENCOWE COTTERELL Electrical Engineer, Waverley Gravelly Hill, near
Birmingham, HUBERT RUSSELL, Electrical Engineer 13 Lanier Road, Lewisham, do
hereby declare the nature of this invention to be as follows:-
In electric switches the combination of the following: improvement in the manner
of operating an electric switch by means of a loose lever whereby, either in the
process of closing the circuit or in exerting the lever preparatory to releasing the
contact piece, a spring is compressed or brought into a state of tension, the same
acting on the contact piece & imparting to it a tendency to break contact. The
contact piece is held in check by an improved mechanical device which is either
released automatically on the controlling lever reaching a certain point in its swing
(which point is capable of adjustment) or else independently by a mechanical device.
The contact piece is replaced by the reverse action of the loose lever and is locked
automatically by the mechanical device above referred to.
Dated this 1st day of November 1900
HUBERT RUSSELL.
MORTON BLENCOWE COTTERELL.
mprovemen 11
Switches.
We, MORTON BLENCOWE COTTERELL, Electrical Engineer of Waverley Gravelly Hill,
in the County of Warwick, and HUBERT RUSSELL, Electrical Engineer of 13 Lanier
Road, Lewisham, in the County of Kent, do hereby declare the nature of this
invertion and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement :-
Our invention has for its object improvements in electric switches as hereafter
described, and the same will be best understood by describing the invention with
reference to the accompanying drawings, wherein,
Fig. 1. is a side elevation of an electric switch constructed according to our
invention.
Fig. 2. is a plan of an electric switch constructed according to our invention.
Fig. 3. is a front elevation of an electric switch constructed according to our
invention.
Fig. 4. is a back elevation of an electric switch constructed according to our
invention.
A copper brush or U piece A, pivotted with respect to one end to the saddle C by
the pin M, completes an electrical contact between the two contact pieces B, B.
[Price 8d.]

page_text: When the switch is in the "on" position as shown in Fig. 1. the trigger or locking
piece D acting about the pin L and impelled by the spring K takes up a position
beneath the brush or U piece A preventing any movement of the switch in the
direction of the "off" position. A handle G is attached to a rocker or lever E acting
about the pin M. This lever, which it will be seen acts about the same centre as the
U piece A, is attached thereto by a spring J which is so arranged that when the
brush and lever are in the position shown in Fig. 1. J is out of tension, but on moving
the handle G in an upward direction the spring J is gradually brought into a state
of tension tending to urge the brush A out of the contacts B, B. As before explained
H is locked in its position by the trigger D. Now the lever E is provided with
two projections, or cams N, N, and these are so placed that on the lever E being
raised by the handle G to a certain predetermined distance the cams N, N, pressing
on the trigger D, cause its removal from beneath the U piece and the latter is free
to fly up into the "off" position.
We also apply the principle of this invention in slightly modified manner
particularly for use on high voltage circuits. For instance we attach the lever E
rigidly to the pin M and dispensing with the trigger D as shown we place a catch or
clip on the contacts B, B for the purpose of locking the brush A in position, whereby
the locking effect above described is obtained. In this case we employ cord or
cat-gut or other insulating material which we attach to the pin M as regards one of
its ends and to the catch above referred to as regards its other end. Then on the
lever E being moved in an upward direction, the pin M also revolves, winding the
cord, cat-gut or other insulating material referred to above, tightly, and by these
means releasing the catch, which as described releases the brush. By altering the
tension of the cord, cat-gut or other insulating material an adjustment may be
effected having regard to the exact moment of break of the brush and its contacts in
relation to the distance through which the lever is moved. Or the same may be
effected in any other similar manner; we quote the above as two particular
applications of the invention.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what we
claim is :-
1. In electric switches the use of a lever arm, as distinct from the contact arm
in combination with a spring so arranged that the spring is not in tension until the
lever arm is withdrawn from the contact arm.
2. The use in electric switches of a stop, catch, clip, bolt, pawl, shutter, or other
device to hold the contact arm in the "on" position and there keep it locked until
such time as the actuating spring is in sufficient tension to throw the contact
arm out of contact upon the withdrawal of the said stop, catch, clip, bolt, pawl,
or shutter or other device.
3. In electric switches a means of adjusting the time of breaking of contact in the
relation to the movement of a loose lever as above described.
Dated this 29th day of July 1897
M. BLENCOWE COTTERELL.
HUBERT RUSSELL.