Year: 1888

page_text: A communication from abroad by GEORGE WESTINGHOUSE, Junior, of Pittsburg,.
County of Alleghany, State of Pennsylvania, United States of America,
Engineer.
1, WILLIAM PHILLIPS THOMPSON F.C.S. M.I.M.E. of the Agency for Foreign Patent
Solicitors, 6 Lord Street, Liverpool and 6 Bank Street, Manchester, both in the County
of Lancaster, and 323 High Holborn, in the County of Middlesex, Civil Engineer, 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
The invention relates to the construction of switches for controlling the circuit-
connections of dynamo-electric generators, delivering currents of high potential.
The object of the invention is to provide convenient and reliable means for securing
the connections without danger to the operator, and in such manner that the
apparatus will not be injured by the sparks formed upon completing and interrupting
the connections.
The invention will be described in connection with the accompanying drawings.
Figures 1 and 2 show one form of the switch in connection with a safety device,
figure 1 being a plan and figure 2 a side view. Figures 3 and 4 are respectively a
front elevation and a side view of another form.
Referring to the figures 1 and 2, A represents a base of non-conducting material
such as wood. There are two switches shown, one being employed for cach pole of
the generator. One only, however, need be described in detail. A conductor Lis
fastened to a binding plate a secured to the base A. This plate is provided with a
fusible strip c', which connects it with a second plate 6. This plate 6' may be con-
nected, by means of a suitable switch-plug with a binding-plate e'. This plate e¹ is
in turn connected by a conductor with a spring contact-plate A. A second contact-
plate is employed for receiving a conductor L' passing to the apparatus to be
supplied with currents. This second plate is upon the opposite side of the switch
from the plate k' thus separating the conductor L' from the conductor f as far as
practicable.
A lever K is employed for connecting the two spring plates with each other when
desired. This lever is pivoted at n and is provided with a handle n' of non-conducting

page_text: material. The lever is formed with a biade or knife-edge k which passes hetween the
respective springs, and, thus forming good connections. The movement of
the lever may be sudden and thus form the connections quickly. The blade is
preferably widened toward its outer end so as to make contact with both sets of
springs at about the same time.
The base is preferably fastened in a vertical position so that when the switch is
closed the handle n'is toward the wall and projecting downward. By simply throwing
the handle outward the switch will be opened. This is of great service in that it
renders it very easy to determine the condition of the several switches of a group at
a glance.
As it frequently chances in connecting generators together, or from other causes,
such as the formation of short-circuits, the safety-strip c may be burned out, it is
desired to provide, in connection with the switch, a second safely strip c². This
connects the plate e¹ with a plate a². The plate a³ may be electrically connected with
the plate a¹ by a switch-plug, in case the safety-strip c' is burned out. This affords a
ready method of substituting a new fusible strip without delaying the operation of the
machines. For the purpose of holding the lever K in either of its two positions, a
springs is placed in the socket N. This serves to press a rounded pin & against the
squared end of the lever K, and it prevents accidental displacement.
Where it is desired to connect the terminals of any given electric circuit with
either of two pairs of conductors at will, the form shown in figures 3 and 4 is
useful. A lever is employed carrying four contact blades, with four sets of contact
plates whereby the blades may serve to complete the connections of a source of
electricity with one pair of conductors when in one position, with another pair in
another position, and to sever all its connections when in an intermediate position.
Referring to figures 3 and 4, the base A carries two plates a' and a² insulated from
each other. The circuit-controlling lever B is constructed with two arms or levers 61
and pivoted at one end to the respective plates at and a². These are of metal and
are connected at their remaining ends with a transverse plate or bar of metal
insulated therefrom, as shown, by the thimble rings c¹, c. This bar b carries a
handle B of non-conducting material by means of which the entire structure may be
turned upon the pivots, ². These pivois extend through upright lips upon the
plates a, a, and preferably the pivots turn in these lugs and are fastened into the
arms 6 and 6, by screws e¹ and so that they cannot slip out.
The arm carries two circuit-closing blades f¹ and g¹ projecting from opposite
sides. The arm is likewise provided with blades, one only of which, y, is
shown. It is designed that these blades shall serve to complete the connections
of different electric circuits according to the position of the circuit-controlling lever.
Thus, when the lever is down to the position shown in the drawings, the blade will
be in contact with two contact plates H and K, and the corresponding blade upon
the arm will be in contact with two plates H and K. When the lever is thrown
in the opposite direction the blade g' and the corresponding blade will be in contact
with the plates M₁ and N and M2 and N2 respectively.
The plate His preferably formed with two lips ', h, projecting upon opposite
sides of the blade, and likewise the plate K¹ has two lips k¹, k, for receiving the
sane blade. These lips may be of resilient copper and sufficiently near together
to be forced apart by the blade as it enters and thus afford good frictional contacts
with the blades. The other plates M, N, etc., are similarly constructed. The contact
lips,, are preferably fastened into their several plates by screws or rivets v, v.
For convenience of construction the plates K' and N are formed in one piece, being
shaped to project upon opposite sides of the pivoted plate a¹; and likewise the
plates K and Ñ³.
The blades upon the respective levers widen toward their outer ends and the ends
of the lips carried upon the respective contact plates are bevoled to correspond, the
angles being such that contact will be made with the several sets of plates approxi-
mately at the same time when the lever is turned in either direction.
It is designed that the terminals of a source of electricity, such for instance as an

page_text: alternate-current electric generator A³, shall have its respective poles connected by the
conductors 1 and 2 with the plates K¹, N1, and K2, N2. The plates H and H³ are
respectively connected with main lines or feeders L and L for instance, and the
plates M and M2 are connected with other lines L³ and L. By throwing the
handle B of the lever B in one direction or the other, circuit connections may thus
be made from the generator to either pair of lines at will.
For the purpose of interrupting the connections of the generator the lever may be
placed in a position midway between the sets of plates, and for the purpose of holding
it in such position, bolts are inserted in the plates a¹ and a². These are normally
forced upward against the corresponding arm or 2 by a spring r.
At the proper
point in each arm or there is proferably formed an indentation as shown at
receiving the head of the bolt and holding the arm midway between the sets of plates.
These springs and bolts also afford sufficient friction to hold the lever B in any
desired position.
for
The lever itself is not in connection with the generator or source of electricity, when
the switch is in its intermediate position and the parts are so arranged as to complete
the connections with the outside conductors simultaneously with or approximately
simultaneously with the completion of the connections with the generator.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, as communicated to me by
my foreign correspondent, I declare that what I claim is :-
1. The combination with a movable lever, of two insulated contact devices both of
which are insulated from the lever and located in the plane of movement of the lever
and each consisting of lips or springs pressing toward each other and a contact blade
upon the lover adapted to make electrical connection with both of said devices by
passing between the contact lips, said blade being narrowed or beveled toward the
pivot of said lever, whereby electrical connection is made with both contact devices at
the same time.
2. The combination with a supporting base, of two arms or levers in different
planes, a handle for moving the same, contact plates carried upon the respective sides
of each lever, and two sets of contact-blades applied to each lever, said blades being
narrowed toward the point of support of the levers, and said contact plates being
beveled in a corresponding direction.
3. The combination with two levers located in different planes and a single han lle
with which both are connected, of two sets of contact-plates applied to each lever, one
contact-plate of each set being connected with a corresponding contact-plate on the
other set, and a retaining device normally tending to hold the levers in a position
midway between the sets of contact plates.
Dated this 28th day of May 1888
WM. P. THOMPSON & Co.,
Agents for the Applicant.