Improvements in the Connections of Electric Motors with the Sources of Electricity from which they are Supplied.
Year: 1892

page_text: Date of Application, 16th Sep'., 1392
Complete Specification Left, 16th June, 1893-Accepted, 22nd July, 1993
PROVISIONAL SPECIFICATION.
Improvements in the Connections of Electric Motors with the
Sources of Electricity from which they are Supplied.
We, WOODHOUSE & RAWSON UNITED, LIMITED, and WILLIAM STEPNEY
RAWSON, all of No. 88 Queen Victoria Street, in the City of London, Electrical
Engineers, do hereby declare the nature of this invention to be as follows:-
This invention relates to the connections of an electric motor to the batteries,
either primary or secondary, which supply it, in such a manner as to provide against
danger to the motor from excess of current, and yet to allow of its being worked
with more or less current at various speeds. For this purpose, in the simplest
arrangement of connections according to this invention, we employ two batteries or
groups of batteries, which are connected to the motor through a switch so arranged
that they can supply the motor either parallel or in series.
Between the one battery or group and the switch we place a safety fuse or cut-
out such as will give way when the current exceeds the amount that the motor can
safely take.
Between the other battery or group of batteries and the switch we place a
stronger safety fuse or cut-out that will stand a greater current. In starting the
motor, we connect the batteries to it parallel, and then, as only about half the
current comes from each battery, the weaker cut-out does not give way. After
starting, the batteries are connected in series to the motor, and then, if the current
should by any circumstance become greater than is consistent with safety to the
motor, the weaker cut-out will give way and open the circuit. The other battery
may then be connected through the stronger cut-out to keep the motor going until
the weaker cut-out be made good again. In order to provide against delay in
restoring the circuit when a safety cut-out gives way, we prefer to provide several
of the weaker kind and a switch with a corresponding number of contacts so that
when the circuit is opened by one of the cut-outs giving way, it can be immediately
closed by moving the switch to introduce another of these.
Dated this 16th day of September 1892.
ABEL & IMKAI,
Agents for the Applicants.
COMPLETE SPECIFICATION.
Improvements in the Connections of Electric Motors with the
Sources of Electricity from which they are Supplied.
We, WOODHOUSE & RAWSON UNITED LIMITED, and WILLIAM STEPNEY
RAWSON all of No. 88 Queen Victoria Street in the City of London, 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 the connections of an electric motor to the batteries,
either primary or secondary, which supply it, in such a manner as to provide against
danger to the motor from excess of current, and yet to allow of its being worked
with more or less current at various speeds. For this purpose, in the simplest
arrangement of connections according to this invention, we employ two batteries or
groups of batteries which are connected to the motor through a switch so arranged
that they can supply the motor either parallel or in series. A switch of this kind
is described in the Specification No. 3234 of 1892. Between the one battery or

page_text: group and the switch we place a safety fuse or cut out such as will give way when
the current exceeds the amount that the motor can safely take. Between the other
battery or group of batteries and the switch we place a stronger safety fuse or cut
out that will stand a greater current. In starting the motor, we connect the
batteries to it parallel, and then, as only about half the current comes from each
battery, the weaker cut out does not give way. After starting, the batteries are
connected in series to the motor, and then, if the current should by any circum-
stance become greater than is consistent with safety to the motor, the weaker cut
out will give way and open the circuit. The other battery may then be connected
through the stronger cut out to keep the motor going until the weaker cut out be
made good again. In order to provide against delay in restoring the circuit when
a safety cut out gives way, we prefer to provide several of the weaker kind, and a
switch with a corresponding number of contacts, so that, when the circuit is opened
by one of the cut outs giving way, it can be immediately closed by moving the
switch to introduce another of these. A multiple cut out of this kind is described
in the Specification No. 5141 of 1892.
Fig. 1 is a diagram shewing two batteries B1 B2, each of which may be a group
of batteries, connected by switch S parallel to a motor M, one of the leads from B
having in its course a cut-out a which will give way when the current exceeds what
the notor can safely take, the lead from B' having a stronger cut out A. Should a
give way, the motor will receive current from B' alone until the cut out a be made
good. Fig. 2 shews the two batteries connected to M in series. Should a in this
case give way the switch can be moved to the position shewn in Fig. 1 keeping B₁
in circuit with the motor through the stronger cut out A.
Having now particularly described and ascertained the nature of our inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
In combination with a pair of batteries or of groups of batteries and a switch for
connecting the pair parallel or in series to a motor, two safety cut outs of different
strengths, substantially as and for the purpose set forth.
Dated this 16th day of June 1893.
ABEL & IMRAY,
Agents for the Applicants.