Combined Apparatus for Regulating the Supply of Electricity to Lamps, Motors, and other Electrical Apparatus.
Year: 1898

page_text: Date of Application, 31st Oct., 1898
Complete Specification Left, 31st July, 1899-Accepted, 2nd Sept., 1899
Combined Apparatus for Regulating the Supply of Electricity to
Lamps, Motors, and other Electrical Apparatus.
We, ERNEST EDGLEY PRESTWICH and LESLIE NEWMAN BURT, trading as
Prestwich & Burt, of 65, River Front, Kingston-on-Thames, in the County of
Surrey, Electrical Engineers, do hereby declare the nature of this invention
to be as follows:-
Our invention comprises combined apparatus and resistances or choking coils
for regulating the current supply to electrical apparatus generally, but more
especially to multiple circuits feeding lamps, motors, and the like, and has for its
object to provide simple and handy means whereby the degree of light, power or
speed as the case may be can be rapidly and easily adjusted and regulated
as required.
Our invention is, for example, particularly useful in theatres, and such like
places, where it is required to vary the light intensity for scenic effects or other-
wise with great rapidity and frequency. The means we employ may be used
for regulating the current supply to a number of circuits or to any one or any
combination of such circuits.
According to our invention we connect in each circuit to be regulated an
adjustable resistance or choking coil, which for alternate currents may be a choking
coil and for continuous currents a resistance of suitable kind; and in combination
with each such resistance we employ a mechanical apparatus suitably connected
to each of same whereby the position of the moving part of any one or any com-
bination of such resistances can be regulated and the current supply varied as
required. The said apparatus comprises a rotary shaft carried in bearings and
provided with a handle or operating means and speed gear if required. Upon
the shaft, at convenient distances apart, are fixed a number of notched wheels
corresponding to the number of electric circuits separately employed; alongside
of each such notched wheel is mounted loose on the shaft a grooved pulley which
is provided with means such as a hand lever with spring detent for locking the
loose pulley to the fast wheel when required; also a retaining device is provided
by which the locking device may be rendered inoperative when that particular
circuit is not in use. Each of these pulleys is separately connected by a cord
or the like to the moving part of one of the circuit resistances above referred to,
and the said connection may be made either directly or indirectly through the
medium of an endless band or otherwise; guide pulleys are used for change of
direction, and counterweights where necessary.
To vary the current in any of the circuits the resistance therein is first
adjusted by freeing the detent from the notched wheel by the hand lever, suffi-
ciently rotating the pulley and relocking same to its fast wheel in required

page_text: position, thereby increasing or decreasing the resistance until the required effect
is produced. On rotating the pulley shaft by the handle or otherwise only the
wheels which are locked as described to the operating pulleys will act upon the
resistances in the corresponding circuits, the remainder being idle. Thus by
simple operation of the locking levers and the rotary shaft the whole or any
required combination of the circuits can be used or omitted, and the current in
those used varied to suit requirements.
Dated this Thirty-first day of October 1898.
Combined Apparatus for Regulating the Supply of Electricity to
Lamps, Motors, and other Electrical Apparatus.
We, ERNEST EDGLEY PRESTWICH and LESLIE NEWMAN BURT, trading as
Prestwich & Burt, of 65, River Front, Kingston-on-Thames, in the County of
Surrey, 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:.
Our invention comprises combined apparatus and resistances or choking coils
for regulating the current supply to electrical apparatus generally, but more
especially to multiple circuits feeding lamps, motors, and the like, and has for its
object to provide simple and handy means whereby the degree of light, power, or
speed, as the case may be, can be rapidly and easily adjusted and regulated
as required.
Our invention is, for example, particularly useful in theatres and such like
places where it is required to vary the light intensity for scenic effects or other-
wise with great rapidity and frequency. The means we employ may be used
for regulating the current supply to a number of circuits or to any one or com-
bination of such circuits.
In further description we will refer to the accompanying drawings, of which
Figs. 1 and 2 are respectively side and front elevations of an apparatus made in
accordance with our invention as applied to alternate current circuits, and
Fig. 3 is a side elevation of an apparatus as applied to continuous current
circuits.
According to our invention we connect in each circuit to be regulated an
adjustable resistance, which for alternate currents may be a choking coil Jas
in Figs. 1 and 2, and for continuous currents a resistance of suitable kind such
as J in Fig. 3, and in combination with each such resistance we employ a
mechanical apparatus suitably connected to each of same whereby the position
of the moving part of any one or any combination of such resistances can be
regulated and the current supply varied as required. The said apparatus com-
prises a rotary shaft A carried in bearings and provided with a handle or
operating means B and speed gear such as worm gear if required. Upon the
shaft A, at convenient distances apart, are fixed a number of notched wheels D
corresponding to the number of electric circuits separately employed; alongside
of each such notched wheel is mounted loose on the shaft a grooved pulley E
which is provided with means such as a hand lever F and spring
detent for locking the loose pulley E to the fast wheel D
required; also a retaining device is provided by which the locking
when

page_text: in use.
device may be rendered inoperative when that particular circuit is not
For this purpose the handle F1 of the lever F is made telescopic therein
and formed in one with or connected to the detent g, a bayonet joint f together
with a return spring is provided so that by withdrawing the handle and
detent g against the spring the detent is withdrawn from engagement with
the notched wheel D and the parts are locked in this position or released by said
bayonet joint f. Each of the pulleys E is separately connected by a cord or the
like to the core of the choking coil J, Figs. 1 and 2, or, as in Fig. 3, to the
moving part or sliding contact of one of the circuit resistances JI; the said
connection may be made either directly or indirectly through the medium of an
endless band or otherwise; guide pulleys such as are used for change of
direction, and counter weights where necessary as at W, Fig. 3, or as shown in
Figs. 1 and 2 the core j of coil J may itself serve as the weight, and it is provided
at its lower end with a switch contact block o insulated from the coil and
arranged to fit into and make contact with switch jaws p p when the core jis
completely out of the coil J, thus cutting the latter out of the circuit, the
connections of the switch being suitably arranged for this purpose. This device
may also be applied to the arrangement shown in Fig. 3.
from
In operation, to vary the current or pressure in any of the circuits,
the resistance therein is first adjusted by freeing the detent
the notched wheel D by withdrawing the handle F, and then by the hand
lever Fsufficiently rotating the pulley E and relocking same to its fast wheel D
in required position, thereby increasing or decreasing the resistance until the
required effect is produced. On rotating the pulley shaft A by the handle B
and gear C or otherwise, only the wheels D which are locked as described to the
operating pulleys E will act upon the coils J or resistances J which are in the
corresponding circuits, the remained being idle. Thus by simple operation of
the locking levers F and the rotary shaft A the whole or any required combination
of the circuits 1, 2, 3, and so forth can be used or omitted, and the current
in those varied to suit requirements. Should the cords break, the pulley give way,
or the stop catch slip, the weight of the core i would cause it to fall, the
switch op making contact, thus allowing the full current to flow, that is, on
theatre or other lighting circuits the lights would be fully incandesced, whereas
in the ordinary regulating gears the reverse action occurs.
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. The use in combination with a number of circuits and a series of resistances
for said circuits, of a rotatable shaft adapted to be connected and disconnected as
required by a detent or locking device to a number of wheels or pulleys loose
and adjustable on said sliaft and suitably connected to and adapted to operate
and adjust the series of resistances or choking coils for each circuit so that by
adjusting or locking or releasing said pulleys or rotating the shaft any required
combination of the circuits can be omitted or regulated to suit requirements,
substantially as described.
2. The combined apparatus for use in the regulation of a number of electric
circuits comprising a number of choking coils or resistances controlling a number
of corresponding separate circuits, each coil or resistance having its core or
moving contact connected by cords or equivalents to a pulley or wheel loose upon
a rotatable shaft, operating handles on said loose pulleys having a spring-pressed
detent device for adjusting and connecting and disconnecting same to notched
wheels fixed to the shaft so that the position of each pulley and its coil or
resistance may be adjusted independently, and the speed gear for rotating said
shaft to adjust at one movement the whole of the pulleys and resistances
connected thereto, substantially as set forth.
3. The improved combined apparatus for regulating the supply of electricity

page_text: to lamps, motors, and other electrical apparatus, constructed, arranged, and
adapted for use and operation substantially in the manner set forth in reference
to the accompanying drawings.
Dated this is ty
For the Applicants,
J. C. CHAPMAN,
70, Chancery Lane, London, W.C., Chartered Patent Agent,