Improvements in Glow Lamps and Holders.
Year: 1893

page_text: Date of Application, 15th Aug., 1893
Complete Specification Left, 15th June, 1894-Accepted, 21st July, 1894
PROVISIONAL SPECIFICATION.
Improvements in Glow Lamps and Holders.
We, EDWARD MANN of Palace Chambers, 9 Bride Street, Electrical Engineer
and JAMES HOPWOOD of Queen Ann's Mansions, Carpenter both in the City of
Westminster, London do hereby declare the nature of this invention to be as
follows:
The objects of our invention are mainly to save first cost and to economize
current. For this purpose we construct the lamp with two filaments and three
lamp terminals.. The two filaments may be of the same or of different capacity or
candle power. By this means we are enabled to keep one of the filaments in
reserve till the other is burnt out and then to put it into action by reversing the
position of the lamp in its holder. We are also enabled to produce or obtain a
small or a great light by using either one or both of the filaments, and this we may
effect by means of a third wire; the switch would in that case be so arranged that
either the lamp is wholly off, or partially on (that is to say, one filament in circuit)
or wholly on (that is to say, both filaments in circuit); or we may put in circuit
either a filament of small power or one of larger power.
Dated this 15th day of August 1893.
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.
Improvements in Glow Lamps and Holders.
We, EDWARD MANN, of Palace Chambers, 9 Bridge Street, Electrical Engineer,
and JAMES HOPWOOD of Queen Anne's Mansions, Carpenter, both in the City of
Westminster, London, 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 main objects of our invention are to economize current while affording
facility for varying the intensity of the light of glow lamps. Hitherto it has not
been possible to vary the intensity of the light without the interposition of
resistance which involves loss of current. But it has been considered very desirable
in many cases (for instance in cabins on board ships or in hospital wards or bed-
rooms) to be able to vary the light from full on to a subdued fight, and in other
instances to vary the light in other proportions, provided it could be done in a
suitable and economical manner.
Our invention consists in the application of two or more incandescent filaments
of the same or of different candle powers enclosed in the same or separate bulbs
on a holder, fitting or bracket in combination with a multiple-way switch all as
hereinafter described. We may thus for instance combine two or three filaments
of the same or different candle power within the same bulb and arrange a switch
in the holder so as to be able to turn on current to one, two or all filaments, or we
may enclose each filament in a separate bulb; or we may combine with one switch
and arrange on one holder or fitting one filament within one bulb and one, two or
three filaments within another, or the object of the invention may be attained in
various other ways as will be understood from the examples which we will now
describe.

page_text: Figure 1 shews an Edison screw socket lamp with two filaments and double
terminal and arranged for skin return circuit ;
Figure 2 is plan of socket.
Figures 3 and 4 are similar views of a double filament lamp with bayonet joint
socket and two terminals with skin return.
Figure 5 is a vertical part sectional view of a holder with switch B adapted to
turn on current either (in case of a two way switch) to a 2 filament lamp C of say
16 C.P., or to a single filament lamp D of say 2 C.P.; or in case of a three way
switch the latter would be to turn on either one or other or both or in case of a
four way switch either one or both filaments in the lamp C could be put into
action.
Figure 5 shews two lamps C and D on the same holder and having a multiple
way switch B arranged above the holder.
In Figure 6 is shewn a lamp bracket A provided with two glow lamps C and D
of the construction Figures 1 to 4 or Figure 5 and having a common multiple
switch B. Assuming as an example that C is of the 16 C.P. and D of 2 C.P. the
switch will admit of C and D being on together thus emitting a light of 18 C.P.
or C alone emitting 16 C.P. or D alone emitting 2 C.P. But the candle power of
the two lamps may be equal or in any other desired proportion.
Figure 7 shews an equivalent construction in which the switch B is placed
below.
Figure 8 shews a bracket A to which are connected a glow lamp D and a glow
lamp in a globe C¹ the leads for each lamp being led to a four-way switch away
from the bracket and placed at the door of the room or in any other desired position,
the results obtainable being also in this case the same as in Figure 6.
Figure 9 shews an arrangement like Figure 6 except that the two glow lamps
are within globes C¹ and D¹.
In Figures 10 and 11 are shewn two arrangements with a glow lamp D and a
glow lamp in a globe C¹.
In Figure 12 is shewn a bracket or standard A which carries a glow lamp D and
two glow lamps within globes C¹ and C¹.
In the above Figures 6 to 12 the lamp C or C¹ may be with two filaments each
for instance of 8 C.P. The switch B would then be so arranged that the light
emitted could be either of 2 C.P. (say from the lamp D) or 10 C.P. (from the
lamp D and one of the filaments in a lamp C) or 18 C.P. (from the lamp D and
from both filaments in a lamp C). In the case of the lamp stand Figure 12, if
cach lamp C¹ had two filaments of 8 C.P. each (or one of 16 C.P.), the light
emitted may with a four-way switch be either 2 C.P., or 16 C.P., or 34 C.P.
Figure 13 a plan view, Figure 14 a central section and Figure 15 a plan with
the cap removed of a three-way switch applicable to the brackets for the lamps
shewn in Figures 1 to 6 and also in principle to the fittings Figures 7 to 12. The
main lead is at N connected to the metal plate E the latter having a spring
portion E which makes contact with the metallic corner mounting F¹ which is
fitted to the switch plug F. The other side of the corner mounting F¹ makes
contact with the spring part E2 of the metal plate Ex which we will suppose leads
to a 2 C.P. lamp. The metal plate Exx we suppose to be connected to a lamp of
16 C.P. and the metal plate Exxx to "off.” It will thus be understood that the
switch may be turned either to Ex or to Exx or to E***.
For a four-way switch the plug F would be a pentagon in section for a five-way
switch a hexagon and so on. If a four-way switch is for instance applied to a lamp
with two filaments of different candle powers within the same bulb as in Figures 1
to + either of the burners may be used alone, or they may both be used in series
or in parallel so that four degrees of light are afforded.
Figures 16, 17 and 18 shew a two-way switch of somewhat similar construction
to Figures 13-15 so that we may for instance have the current turned on either to
a 2 C.P. or a 16 C.P. filament.
Figure 19 shews diagrammatically six different positions which a switch may

page_text: take, one say for putting into circuit a 2 C.P. lamp, the next an 8 C.P. and a 2 C.P.,
the next an 8 C.P., an 8 C.P. and a 2 C.P., the next an 8 C.P. and an 8 C.P., the
next an 8 C.P., and the last the off position.
It will be understood from the foregoing that the saving in current effected by
our invention also involves a saving in the life of those filaments which are turned
off when their light is not required.
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 application and use of a holder provided with multiple switch and skin
return circuit and a lamp containing two or more filaments substantially as and for
the purposes set forth.
2. The application and use of a holder provided with multiple switch and two
lamps each containing one or more filaments substantially as and for the purposes
set forth.
3. The application and use of holders and multiple switch as firstly and secondly
claimed in combination with fittings or brackets as described and shewn.
Dated this 15th day of June 1894.
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.