Improvements in and connected with Mounting Incandescent Lamps for Safety Purposes, particularly applicable to Electric Miners' Safety Lamps.
Year: 1892

page_text: Date of Application, 15th Jan., 1892
Complete Specification Left, 17th Oct., 1892-Accepted, 14th Jan., 1893.
PROVISIONAL SPECIFICATION.
Improvements in and connected with Mounting Incandescent Lamps
for Safety Purposes, particularly applicable to Electric Miners'
Safety Lamps.
I THEOPHILUS COAD, 52 Chancery Lane London W.C. Electrician do hereby
declare the nature of this invention to be as follows:-
:~
According to this invention the incandescent lamp is held on a flexible support
so as to offer no resistance to a blow if it should be knocked against anything and
any action which moves it out of its normal position breaks the electric circuit and
so immediately puts out the lamp which relights on coming back to its normal
position.
In carrying out the above I mount on front of a suitable battery a holder for the
incandescent lamp, preferably a short length of tube in front of which is attached
a disc of india rubber with a hole in center. The incandescent lamp is preferred
to be connected to a wooden cup or holder arranged to fit in the hole in the india
rubber and be held therein by a groove.
The leads for the current pass from the
terminal hooks of the lamp through the wood and project beyond in the shape of
two stems; these bear on contact points within the tubular holder.
A slight
movement of the lamp on one side breaks contact or short circuits the battery and.
puts out the lamp; this is brought back to its normal by spring appliance when it
relights by the circuit being completed.
As the making and breaking contact is behind the india rubber disc no
inflammable gases can be ignited by the sparking.
The incandescent lamp could be so held as to be pushed through the india
rubber disc as additional security against accident.
Dated. this 15th day of January 1892.
FREDERIC PRINCE,
Agent for Applicant.
COMPLETE SPECIFICATION.
Improvements in and connected with Mounting Incandescent Lamps
for Safety Purposes, particularly applicable to Electric Miners'
Safety Lamps.
I THEOPHILUS COAD of 52 Chancery Lane, London, W.C., Electrician, 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 :-
According to this invention the incandescent lamp is held on or by a flexible
support so as to offer no resistance to a blow if it should be knocked against
anything and any action which moves it out of its normal position, breaks the
electric circuit or short circuits the lamp and so immediately puts out the same,
which relights on coming back to its normal position. As the making or breaking
the contact behind the flexible holder which is preferred to be an india-rubber
disc fitted gas tight, no inflammable gas can get behind it so that no explosive gases
can be ignited should there be any sparking.
To enable my invention to be properly understood I will proceed to describe the
same with aid of the accompanying drawings.
Figure 1 is a side view of a miner's lamp complete showing the above invention
in section.
Figure 2 a back view of the safety part detached from battery.

page_text: :
A is the battery on the front of which is secured by screws a brass envelope B
electrically connected at C to one pole of the battery in the front of this envelope B
is secured an india rubber dise E through the centre of which is fixed a wooden
cup F into the front of which is cemented the incandescent lamp G one terminal
hook of this lamp is connected to the inside of B by a short length of wire and so
by the lead C is in electrical connection with one pole of the battery. Through the
centre of the back of cup F is a rod H which carries a star J of conductive metal
held normally just clear of the inside of envelope B. The end of rod H is
connected to the other pole of the battery by a short length of wire, connected to
the lead K. It will thus be readily understood that the lamp as in its normal
position that is as shown at Figure 1, is in proper electrical connection with the
battery but should the lamp be pushed on one side which the flexibility of the india
rubber disc admits of, one of the points of the star J comes in contact with the
inside of B and so short circuits the lamp, which when the pressure that holds it
out of its normal position is removed it comes back to its usual position when the
point of star breaks contact with the inside of B and so the circuit is again
completed and the lamp relights. For further protection the incandescent lamp is
covered by a glass envelope L secured by screwed on collar M.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
'claim is
The arrangement for flexibly supporting an incandescent lamp which admits of
it being "short circuited" when it is moved out of its normal position, substantially
as hereinbefore described and illustrated by the accompanying drawings.
Dated 17th day of October 1892.
FREDERIC PRINCE,
1, Quality Court, Chancery Lane, London, Agent for Applicant.