AN IMPROVED FORM OF HOLDER & SWITCH COMBINED FOR INCANDESCENT ELECTRIC LAMPS
Year: 1885

page_text: Electric Lamps.
I ALFRED GRUNDY of 62 Morrison Street Shaftesbury Park London SW
Electrician do hereby declare the nature of my invention for AN IMPROVED FORM
OF HOLDER & SWITCH COMBINED FOR INCANDESCENT ELECTRIC LAMPS to be as
follows:-
Firstly a disc of ebonite wood or other nonconducting material being suitably
connected to the pendant bracket or other electrolier is provided with two pieces
of brass or other conductor one on either side to which the leading wires are con-
nected by binding screws These pieces of conducting material are let into the
circumference of the insulating disc so that their outside edges shall be level with
the said circumference The slot in which they are laid being rather more than
double their width and about a quarter of an inch longer.
Secondly a similar disc of insulating material has attached to either side an arm
of metal of the same width as the contact pieces on the first part, one end of each
of these metal arms is provided with a shoulder of such a width as to turn in the
space left between the first mentioned metal pieces and the ends of the slots.
-
The other ends of these two metal arms are made of a fan shape and so bent as
to partially encircle the neck of the lamp and hold it in position, while connection
is made between these arms and the lugs of the lamp by means of a suitable
binding screw.
The lamp being properly secured to the 2nd part and the leading wires connected
to the first part, push the shouldered ends of the metal arms in the slots alongsido
the contact pieces. No connection will be made until the 2nd part is turned to the
right when the shoulders will engage the contact pieces and the lamp will light, to
extinguish the lamp turn it to the left when contact will be broken. To prevent
the lamp from falling out when switched off the upper ends of the slots are made
slightly deepest.

page_text: Improved Form of Holder and Switch Combined for Incandescent
Electric Lamps.
I, ALFRED GRUNDY of 62 Morrison Street London SW Electrician do hereby
declare the nature of my invention for AN IMPROVED FORM OF HOLDER AND
SWITCH COMBINED FOR INCANDESCENT ELECTRIC LAMPS and in what manner the
same is to be performed, to be particularly described and ascertained in and by
the following statement :-
An upper part of Wood ebonite or other insulating material A (see Figs. 1. 2.
or 3 in which the symbols are all synonymous) is secured in a suitable manner to
the pendant bracket or other support having a hole or holes through the same
longitudinally for the passage of the leading wires. B is a groove circumferentially
round the part A at a convenient distance from the bottom. C is a piece of brass
or other conductor one on either side of the part A opposite to each other the ends
being turned underneath the part A where are binding screws S for securing the
leads the two pieces of metal (one of which only can be seen in Fig. 2) becomes
the terminals or electrodes of the pendant bracket or other electrolier.
A disc of suitable insulating material, D has on opposite sides pieces of spring
brass or other conductor with a shoulder made to fit in the circular groove B, these
metal arms are spread out in a fan shape.so as to partially encircle the neck of the
lamp and hold it rigidly in position see G. Two blocks of metal H H are fixed to
the arms E and provided with a binding screw and washer for securing the lugs of
the lamp, the lamp being attached to the part D and pushed upward until the
shoulders of the arms clip in the groove B the lamp can be switched on or off at
will by turning the part D a quarter of a turn in either direction.
The lamps can be fixed to spare parts D at leisure and in the event of a lamp
wanting replacing it can be done instantaneously without danger of fuzing the
lugs or getting dangerous shocks.
The weight of metal in the conducting parts and all the connections being of a
thoroughly firm nature the variable resistance due to spiral springs hooks etc. is
done away with thus greatly increasing the efficiency of the lamp.
The part A may be secured to the pendant by means of a socket and screw as N
Fig. 1 by a female thread as in Fig. 2.
By a male nipple as Fig. 3 or in any other suitable or convenient manner.
Suitable stops are placed at suitable distances to prevent overturning the part D
so that whenever that part is turned until the shoulder of the arm E comes in
contact with these stops, the contact is either wholly made or wholly broken.
As the contact of both electrodes is broken at the same moment no sparking can
take place.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is
A combined lamp holder and switch for incandescent lamps substantially as
herein before set forth.