Improvements in Means or Apparatus for Regulating the Supply of Electrical Energy to Lamps and other Apparatus
Year: 1892

page_text: Date of Application, 4th Nov., 1892
Complete Specification Left, 14th Aug., 1893-Accepted, 23rd Sept., 1893
Improvements in Means or Apparatus for Regulating the Supply of
Electrical Energy to Lamps and other Apparatus.
We EDWARD PINDER DAVIS of 149 Finchley Road in the County of Middlesex,
Esquire, and ADRIAN CHARLES COLLINS of 61 Old Broad Street, in the City of
London, Electrical Engineer do hereby declare the nature of this invention to be as
follows:-
-
The object of the invention is to effect the regulation of the supply of electrical
energy to electric lamps and other electrical apparatus.
In carrying out our invention we in the case of say an incandescent lamp employ
two or more filaments in one and more than one enclosing vessel and we so connect
and support these filaments that they are removably in electrical connection with
suitable terminals in a holder and these terminals are placed in variable electrical
connection with a suitable series of contact pieces and the contact pieces are capable.
of being placed in contact in selected order with another set of contact pieces by
means of suitable conductors and these latter contact pieces are connected to the
source of electrical energy either continuous or alternating.
The details of the arrangements will be varied accordingly as the object to be
attained is the supply of electrical energy to an incandescent lamp, a motor, or
other means of utilizing the electric force.
For instance for a two filament incandescent lamp we socket the lamp with the
filaments in connection with four terminals and the four terminals in variable.
connection with eight contact pieces connected by two conductors insulated from.
each other connected with two other contact pieces in connection with the source
of energy.
Each pair of terminals may be referred to for distinction as terminals a, a', and
terminals b, b and the two series of contacts to which they are variably connected
as c, c', c, c, and d, d¹, d², a³.
In arranging the lamp for the whole power to pass through the two filaments.
say 16 candles for sake of illustration we should connect a and a¹ to c and b
and b, to d.
Again when only one half that power is required we should connect a, or a¹ to c
and, or to d¹. This is presupposing the resistances of the two filaments to be
equal but should the resistance of the one be greater than that of the other the
connections will be adjusted to vary the amount of current provided for.
Again should only one quarter of the total energy employed be required the
terminal a is connected to the contact piece c², the terminal b to the contact piece d
and the terminals a¹ and b¹are connected together through the contact pieces c³
and d thus throwing the two filaments into series.
This method of effecting the regulation and adjustment of the amount of current.
provided for at one time in a lamp, or other electrical apparatus enables us to
dispense with the necessity of securing equality in the resistances of the two or other
number of filaments or equivalent resistances as the energy absorbed is proportioned.
to the amount of resistance in the circuits.
Dated the 4th day of November 1892.

page_text: COMPLETE SPECIFICATION.
Improvements in Means or Apparatus for Regulating the Supply of
Electrical Energy to Lamps and other Apparatus.
-We EDWARD PINDER DAVIS of 149 Finchley Road in the County of Middlesex,
Esquire, and ADRIAN CHARLES COLLINS of 61 Old Broad Street in the City of
London, Electrical 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 object of the invention is to effect the regulation of the supply of electrical
energy to electric lamps and other electrical apparatus.
In carrying out our invention we in the case of say an incandescent lamp employ
two or more filaments in one and more than one enclosing vessel and we so connect
and support these filaments that they are removably in electrical connection with
suitable terminals in a holder and these terminals are placed in variable electrical
connection with a suitable series of contact pieces and the contact pieces are capable
of being placed in contact in selected order with another set of contact pieces by
means of suitable conductors and these latter contact pieces are connected to the
source of electrical energy either continuous or alternating.
The details of the arrangements will be varied accordingly as the object to be
attained is the supply of electrical energy to an incandescent lamp, a motor or other
means of utilizing the electric. force.
For instance for a two filament incandescent lamp we socket the lamp with the
filaments in connection with three terminals, and the three terminals, are in variable
connection with six contact pieces connected by two conductors insulated from each
other, connected with two other contact pieces in connection with the source of
energy. One of the terminals may be referred to as a² the other as a³ and the
third as a (which is a common return for both filaments) and the two series of
contacts to which they are variably connected as g, h, i, k and g, h, i and k². In
arranging the lamp for the whole of the power to pass through the two filaments
say 16 candles for sake of illustration we should connect at to g, h, i and and h
to a² and a³. Again when less than the whole power is required we should
connect a to g, h, i and a² to h. (This is presupposing the resistance of the two
filaments to be unequal; a more useful combination than two equal filaments.)
Again when less than the last power is required we should connect a* to g, h, i
and a³ to i.
Again should only one quarter of the total energy employed be required the
terminal a³ is connected to the contact piece k and the terminal a³ to the contact
piece thus throwing the two filaments in series.
This method of effecting the regulation and adjustment of the amount of current
provided for at one time in a lamp, or other electrical apparatus enables us to
dispense with the necessity of securing equality in the resistances of the two or
other number of filaments or equivalent resistances as the energy absorbed is
inversely proportional to the amount of resistance in the lanp or lamps.
DESCRIPTION OF THE DRAWINGS.
Fig. 1 shews an external view of an incandescent lamp and its holder.
Fig. 2 shews a vertical section of the same.
Fig. 3, shews a transverse section of the holder taken on the line A B of Fig. 2,
and shewing the lower portion thereof with the supports for contacts.
Fig. 4, shews an underside view of the lamp holder with lamp away.
Fig. 5 shews a plan view of the cap of the lamp, with filling and plates removed
and shewn with the connections of the separate filaments.
Fig. 6 shews a similar view of the lamp with the plates; but removed from the
holder.

page_text: invention.
Fig. 13 shews by a section, Fig. 14 by a plan, and Fig. 15 by an underside view
a switch for working with the holder.
Fig. 16 shews by a sectional view and Fig. 17 by an underside view an alternative
form of holder for use with the switch.
Fig. 18 is a plan view of a lamp cap adapted for use with the holder shewn in
the two previous figures.
Figs. 19 and 20 shew by a sectional view and underside view respectively another
alternative form of holder and Fig. 21 shews by a side view a cap for use with
the same.
Fig. 22 shews another form of holder in which hooked wires and a spiral spring
are used.
Figs. 23 and 24 shew by similar views to Figs. 19 and 20 another alternative
form of holder for use with the regulating switch and
Figs. 25 and 26 shew by plan view and side view respectively a lamp cap for
use with this holder.
Figs. 27, 28 and 29 shew another alternative form of holder to be used with the
switch.
Fig. 27 being a vertical section, Fig. 28 an underside view and Fig. 29 a section
shewing the top terminals and the clip.
Figs. 30, 31 and 32 shew a lamp with filaments similar to that shewn in Figs. 1
and 2 but for use with a different form of contacts.
Fig. 30 is a plan view shewing the clips for receiving these contacts. Fig. 31 a
plan view with filling and plates removed and shewing the connections of the
separate filaments and Fig. 32 is a side view.
Fig. 33 shews by diagram the arrangements of the respective wires to the holder
and the connections to the switch for carrying out the invention when applied to
electroliers not within reach say electroliers in high rooms suspended overhead or
in the lighting of theatres and other places.
Figs. 1 and 2 shew an ordinary incandescent lamp containing four carbon filaments
of different resistances of ordinary manufacture but so constructed as to carry
current at the required voltage without breaking. The filaments which are
figured a, a' b, bl C₁ c and d, d' are connected to the cap e fixed to separate plates
fastened by insulating cements as shewn in Fig. 6 viz. :-one end of a, al to the
plate marked a and the other end to the plate common to one end of each of the
other filaments marked a¹ b, c, d, the other ends of b, b, c, c' and d, dare
connected to the plates marked with their initial letter. These plates are so placed
in the brass collar, that while they are insulated from each other the contact M
(Fig. 4) can make connection on each singly or on any adjacent two. The
contact M consists of a square brush pressed down by a spring and so placed that
it will make contact on any of the plates. a, b, c, d, b, c and d and the contact N
a round spring plunger is placed so as to make contact on the plate a only, both
these contact pieces are fixed to an insulating block L Fig. 2 and are provided
with two screws which receive the + and series from the main supply. This
insulating piece and contacts are placed in a metal case I which is provided with a
screw at each end, one to take the top of the case G which is secured to it by the
binding ring H and the other to take the moveable portion of the holder K which
is loosely attached by the binding ring J.
This loose portion receives the cap of the lamp contact being made by M and N
and is provided with small knobs for turning and slots to take the projections of
the lamp cap.
The lamp being inserted and the current being switched on from the usual
source the filament a, a¹ is rendered incandescent and on turning the part K the
centre contact always remains on a while M moves over a, b, c¹, d¹. C. b and d
putting in a resistance of slightly varying degree for example in the case where
the filament a, a' is 1666 Ohms resistance which will give on a 100 volt circuit

page_text: 6 candle power b, will be about 42 Ohms resistance c, c¹ about 75 Ohms and d, d'
about 120 Ohms each of which also becomes luminous in turn but the same time
diminishes the light at the same time using a proportionate amount of current to
light produced.
Fig. 7 shews a section of a modified holder which contains three contact
pieces a², a³, a as shewn in Fig. 8 these contacts may be of bayonet form as here
shewn or they may be in form of hooks as in Fig. 22 or side contacts as in
Figs. 16, 17, 19, 20, 23, 24, 27 and 28. The contact pieces are connected with the
plates and 14.
These plates are secured to the insulating block c² which block receives the
vertical sheet of insulating material ³. Through the sheet ca spindle and knob d²
made of insulating material is passed through the centre, on this spindle is mounted
two metallic bars f,¹ Figs. 9 and 10 mounted one on each side of c³ and secured
to 2 by a collar and screw, these bars are turned by the spindle d' parallel over the
plates g, h, and k and ghi and k¹ which plates are in electrical connection by
means of insulated wire of very small gauge with 12 and 1 viz. 1 is connected
with hand, b³ with and i and k¹, and with g, h, i so that when flis on g,
hori, fis on g, h, i and when f¹is on k, f¹ is on k. The bars ff also make
movable contact on 1, which are connected with the source of electrical energy.
Fig. 11 shews by a plan view and Fig. 12 by a side view a lamp suitable to be
used with the bolder m, m', and n, n¹ are ordinary carbon filaments of different
resistances and constructed to work at the different voltages at which the source of
electrical energy is supplied; in this description ", n' shall be the higher resistance
and m m the lower. 'm', n' are connected to the plates and m to p and n to the
plates are insulated from each other by cement and contained in the brass ring t
which fits in the holder u (Fig. 7) or the connection of the filaments being made in
the same way the contacts may be eyes as in Fig. 22 or side connections as in
Figs. 18, 21, 25, 26, 30, 31, 32.
Now when this lamp is socketed in the holder u, a is making contact on s,
a² on p and a³ on . When the bars f, f¹ are turned on g, h, i and g respectively the
current flows through n' when f¹ is on g and hand fon g, h, i the current flows
through both filaments in parallel giving the maximum amount of light, when fis
on hon g, h, i the current flows through m m' when f¹ is on i, and fon g, h, i the
current flows through nn', and when is on hand f on the current flows
through both filaments in series thus lowering the light to its maximum and
while at the same time lowering of the light the number of amperes flowing
through the lamp is proportional to the light produced thus saving a considerable
amount of energy which is lost when resistance is used on the outer circuit.
The last two arrangements are only suitable for lamps that are within range for
manual regulation near the lamp, but in the case of electroliers in high rooms or
theatre lighting it is necessary to use a slightly different arrangement which is
similar in principle to the movable lamp but instead of the movable part a switch
with a number of contact pieces is used.
In Figs. 27 to 32 the lamp (Fig. 32) is similar as regards filaments to the one
(Fig. 2) the connections are arranged in a similar manner but are connected to
different form of contacts. These are shewn in Figs. 30, 31 and 32. v, y, z, ware
the side metallic terminals, the centre contact formed like an inverted conc. The
terminals v, y, a, w are insulated from each other by vulcanized fibre or miconite
pieces, (Fig. 30) while 2 is insulated from the others by the cementing medium
or the several contact pieces can be mounted on and in vulcanized fibre. The large
or main filament a al (Fig. 32) is connected on one pole to z and the other v, the
smallest filament b, 1 (Fig. 32) to y and v, the next c c¹ to and v and the next d, d²
to w and v.
The holder (Fig. 27) consists of metal as shewn at 1. Fig. 28 is plan view
thereof, it has 5 separate terminals which are marked v, y, a, w to correspond with
the terminals on the lamp cap and a cross cut cone to fit into inverted cone in the
cap also marked z.

page_text: These terminals are secured to a block of insulating material (Fig. 27) and
secured at the top with screws and the bottom a washer, the insulating block is kept
in place by a clip. The terminals x, y, t, w are insulated from each other by an
insulating ring 2 (Figs. 27 and 28). To socket the lamp in the holder it is
necessary to press the lamp with the slots v, y, a, wc and inverted cone against the
spring terminals, y, z, wo and cone =. The springs contract through the narrow
neck as shewn (Fig. 32) and when through expand and form contact and hold the
lamp in position. The holder is then wired as shewn in diagram Fig. 33 and
connected to a switch Figs. 13, 14 and 15 which is secured to some convenient
point such as a wall. Fig. 13 is a section, the metallic portions are mounted on
china or slate or any insulating incombustible material, fitted with a cover of the
same material and a similar handle which keys on and is screwed to the spindle 8
Fig. 13 which carries the connecting bar 3 this spindle is carried in a metallic
collar 4 in close contact and is secured by the screw 5 and washer 6, the collar is
connected to one of the leads from the main.
On the same china base are mounted 5 terminals four of which v, y, a, w are
connected electrically by insulated wires with u,,, w. Figs. 28 and 30 and the
fifth not being in electrical connection breaks contact.
All these contact pieces are so placed that the connecting bar 3 never breaks
contact but is either on one contact piece or the edges of any two. Fig. 15 shews
the holes for carrying away the wires and the way in which the contact pieces are
secured to the porcelain .e. by sunk screws. Now when this switch is wired with
the holders and lamps as shewn in diagram Fig. 33 and the connecting bar is on
the current flows through the main filament a a¹ when moved on to the smallest
filament b b is placed in series with a, a', when ou a, c, c¹ in series with a¹ when
on w. d d in series with a a when the light is lowest on account of the increased
resistance of the filament, and when the bar is moved on to the fifth contact pieces
the circuit is broken.
t
23
Figs. 16, 17, 18 shew another arrangement of Figs. 27 to 32. This holder is an
arrangement of the well known bayonet type adapted to suit this lamp.
Figs. 19, 20, 21 shew another arrangement t, y, c, w, are side spring contacts
working in a similar manner to Figs. 21, 28, 30, 32, and in this arrangement to
socket lamp in the holder the lamp is placed with its contacts, y, a, w on the
corresponding terminals v, y, a, w and pressed home when the centre cone
contact enters the inverted cone in the lamp collar and the spring contacts
flatten and when the lamp is far enough in, expand into the four recesses in
the collar, thus making good contact and holding the lamp in position in the
holder.
Fig. 22 shews a holder for using with a loop lamp; the platinum is taken
through the glass and made into loops, 5 in number, corresponding as regards
connections with v, y, z w and . The five terminals are five hooks fastened to
an insulating block. To socket the lamp it is placed against the lower end of the
spring 7 and pushed in until the hooks can be placed through the loops when the
hand is withdrawn and the spring pressing back to its normal condition makes.
contact and keeps the lamp in position.
Figs. 23, 24, 25 and 26 shew an inverted "bayonet" type in which the central
contact is a spring plunger and the four contacts corresponding to v, y, x, w consist
of stiff metallic studs insulated from each, other projecting sufficiently to fit into
4 slots (insulated from each other) in the lamp socket.
To socket the lamp the collar is inserted into the holder so that the four studs in
the holder will travel into the four slots in the collar and pressed home until the
plunger allows the lamp to be turned a quarter inch, when the studs become fixed
and are held in place by the plunger making good contact and keeping the lamp in
place.
On all the lamps a mark should be made corresponding with a similar one on the
holder so that in socketting the lamp the several contacts shall be in correct
connection.

page_text: Fig. 33 is a diagram shewing arrangement for wiring a group of lamps in
conjunction with a regulating switch.
One wire from the main supply is led to the lamps and connected at their
centres by branches. The other wire is led to the switch at o which is in
electrical connection with the switch bar 3. This bar makes continuous contacts
when turned by a handle on v, y, a and w. From , y, and w four wires of small
gauge insulated either separately or contained in one cover insulated from each
other, are led to the lamps which are connected to the lamp through the holder .by
branch wires on the separate terminals , a, y and w. Therefore when the switch 3
is moved over the contacts r, a, y and w the different filaments are consecutively
put in series with the main filament.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we wish it to be understood
that we do not claim generally the combination in one electric lamp of two or more
incandescent conductors and means of connecting them in an electric circuit either
in series or multiple are but we declare that what we claim is :-
In means or apparatus for effecting the regulation of the supply of electrical
energy to incandescent electric lamps and other like apparatus.
1. The use of two or more filaments of different resistances placed in an exhausted
transparent vessel with electrical connections to each filament so arranged that the
electric current can, at will, be caused to flow through one filament alone, or
through any of the other filaments put in series separately with the first or main
filament so as thereby alternatively to attain-with the flow through the main
filament alone a high degree of illumination-or with the flow through the
main filament and a smaller filament a lesser degree of illumination according to
the amount of resistance interposed and thereby at the same time securing a
decrease in the flow of the electric current, substantially as and for the purpose set
forth.
2. Placing two or more filaments of different resistances in an exhausted trans-
parent vessel and so connecting them that the current may be caused to flow
through each filament separately or through two or more of them in parallel or
through two or more in series thereby enabling several alternative degrees of
illumination to be obtained at will and at the same time using an amount of current
which varies directly according to the amount of illumination developed substantially
as set forth.
3. In apparatus in regulating the supply of electrical energy to incandescent
lamps so situated as to require regulation by means operated from a distance. The
combination or arrangement and use of a suitable conductor from the source of
electrical energy to one terminal of a switch having a suitable number of contact
pieces proportionate to the number of filaments in the lamp or lamps the
illumination of which it is designed to regulate. Suitable conductors arranged in
direct connection with the poles of the filaments of the lamps so as to admit of the
current being caused to pass through said filaments in selected order, and a lamp or
lamps having therein two or more filaments of different resistances substantially as
and for the purpose described and shewn in the diagram drawings Fig. 33 with
reference to the detail Figs. 13 to 32.
4. The various constructions or arrangements of lamps and their caps as set forth
with respect to Figs. 1, 2, 5, 6, 11 and 12.
5. The combination or arrangement and use of incandescent electric lamps caps
and sockets substantially as set forth with respect to Figs. 1 to 12.
6. The various constructions or arrangements of parts of incandescent electric
lamp sockets as described and shewn with reference to Figs. 2, 3, 4, 7, 8, 9
and 10.
7. The combination or arrangement of the parts of the various holders and their
lamps and lamp caps substantially as shewn and described with respect to Figs. 19,
20, 21, 23, 24, 25 and 26.

page_text: 8. In regulating the supply of electrical energy to incandescent electric lamps
the various combinations or arrangements of parts of lamp sockets or holders
substantially as shewn and described with respect to Figs. 19, 20, 23, 24, 27, 28
and 29.
9. In regulating the supply of electrical energy to incandescent lamps the
various arrangements or constructions of caps and filaments of incandescent lamps
substantially as described and shewn with respect to Figs. 22, 25, 26, 30, 31
and 32.
10. The various constructions or arrangements of lamp cap and lamp substan-
tially as shewn and described with respect to Figs. 27 to 32.
11. The various arrangements and combinations of parts of apparatus for
regulating the supply of electrical energy to lamps or other like apparatus
substantially as and for the purpose hereinbefore shewn and described.
Dated the 14th day of August. 1893.
WM. BROOKES & SON,
55 & 56, Chancery Lane, London, Agents for the Applicants.