Improvements applicable to Switches used for Electrical Purposes.
Year: 1890

page_text: Date of Application, 24th Nov., 1890
Complete Specific tion Left, 24th Aug., 1891-Accepted, 24th Oct., 1891
PROVISIONAL SPECIFICATION.
[Communicated from abroad by ARTHUR W. TOURNAY HINDE, of Tallooma,
Edgecliffe Road, Waverly, Sydney, N.S.W.]
Improvements applicable to Switches used for Electrical Purposes.
WOODHOUSE & RAWSON UNITED LIMITED, Electrical Engineers & Contractors,
88 Queen Victoria Street London E.C. in the County of Middlesex, do hereby
declare the nature of this invention to be as follows:-
The object of this invention is to simplify the construction of electrical switches
of the various types set forth and to produce reliable and compact appliances for
general and special purposes as may be required. For this purpose we preferably
make use of the laminated form of switch arm or brush though obviously we do not
necessarily confine ourselves to that exact form.
In one arrangement of our improved type as for instance in forming a double
pole switch we prefer to use a single spindle and mount thereon but insulated from
the spindle two pairs of brushes arranged by preference at points diametrically
opposite each other each pair is carefully insulated from the other but any two
brushes forming a pair are electrically connected and arranged to form arms of
different radii this being very compactly effected by fastening the longer radius one
on the top of the other contact plates to suit the brushes and springs handles stops
and other accessories are of course necessary. As alternative plans we may put
the two brushes forming a pair in horizontal alignment instead of vertical or use a
single double ended brush on each side of the spindle attached to a common lever.
For combined charge and discharge or combined dynamo and lamp switches we
may use either of the above arrangements the difference being that each pair of
brushes is quite independent of the other in its movement though rotating around
the same spindle.
For resistance varying switches a convenient arrangement consists in one half of
either of the above forms that is the centre of rotation is quite extraneous to the
switch brush.
For use with accumulators we arrange two similar brushes separated but lying
parallel to each other and only electrically connected by a resistance but with the
spindle as above explained extraneous to the brushes.
November 24th 1890
OODHOUSE & RAWSON UNITED, LIMITED,
GEORGE WORRALL, Secretary pro tem.
COMPLETE SPECIFICATION.
Improvements applicable to Switches used for Electrical Purposes.
We, WOODHOUSE AND RAWSON UNITED LIMITED, Electrical Engineers and
Contractors, of 88 Queen Victoria Street, London in the County of Middlesex, 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 object of this invention is, to simplify the construction of electrical switches
of the various types set forth, and to produce reliable and compact appliances for
general or special purposes as may be required.
For this purpose, we preferably make use of a laminated form of switch arm or
brush, though obviously we do not confine ourselves to that exact form,

page_text: The invention may be understood by reference to the accompanying drawings, in
which similar letters refer to similar parts.
In one arrangement of our improved type. (see Fig. 1.), as for instance in forming
a double pole switch we prefer to use a single spindle through the opening and
mort thereon, but insulated from the spindle two pairs of brushes A-B & C-D
arranged by preference, at points diametrically opposite each other. Each pair is
carefully insulated from the other (insulation is shewn hatched in the figure) but
any two brushes forming a pair are electrically connected, the current therefore
taking the course shown by the arrows, and are arranged to form arms of different
radii, this being very compactly effected by fastening the longer radius, one on the
top of the other as shown. Contact plates to suit the brushes and springs, handles,
stops, and other accessories are of course necessary, according to the special purpose
for which the switch is to be used 'but for clearness as such accessories are common
more or less to all switches it is deemed unnecessary here to illustrate same. As
alternative plans we may put the two brushes forming a pair in horizontal
alignment instead of vertical, as shown in Fig. 2. with dissimilar radii, and in
Fig. 4 with one common radius, in this latter a conducting segunent joins up the
IS
two brushes the discs F F being insulated or of insulating material, or we may use
a single double-ended brush (as shown in plan and elevation of Fig. 3) on each side
of the spindle attached to a common insulated lever.
For combined charge and discharge or combined dynamo and lamp switches we
may use either of the above arrangements the difference being that each pair of
brushes is quite independent of the other in its movement though rotating around
the same spindle.
For resistance varying switches a convenient arrangement consists in one half of
either of the above forms, thus types illustrated in Figs. 5 and 6 are approximately
halves respectively of Figs. 1 and 3, that is in these the centre of rotation is quite
extraneous to the switch brush.
For use with accumulators we arrange two similar brushes separated but lying
parallel to each other (see plan in Fig. 7) and only electrically connected by a
resistance H, but with the spindle as above explained extraneous to the brushes, in
this type of switch, one brush at say G is shortened so that no contact is made at
that end and the resistance H is therefore never short circuited.
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
Ist. The construction or combination of the parts of a switch used for electrical
purposes whereby for a double pole or similar type one common spindle is made
available, the brushes being arranged in vertical alignment as illustrated in and
described in reference to Fig. 1, or in horizontal alignment as illustrated in and
described in reference to Figs. 2. 3. 4.
2nd. The construction or combination of the parts of a switch used for electrical
purposes, whereby for a resistance varying or similar type of switch, the brushes
are arranged as illustrated in and described in reference to Figs. 5 & 6.
3rd. The construction or combination of the parts of a switch used for electrical
purposes whereby for an accumulator or similar type of switch, the brushes are
arranged as illustrated in and described in reference to Fig. 7.
Dated this 24th day of August 1891.
WOODHOUSE & RAWSON UNITED, LIMITED,
W. T. Switchbury, Secretary.