Improvements in Holders for Incandescent Electric Lamps.
Year: 1890

page_text: Date of Application, 9th Aug., 1890
Complete Specification Left, 8th May, 1891-Accepted, 13th June, 1891
PROVISIONAL SPECIFICATION.
Improvements in Holders for Incandescent Electric Lamps.
I, EDWIN PERCIVAL ALLAM of Elm Bank, Romford, in the County of Essex
Electrical Engineer, do hereby declare the nature of this invention to be as
follows:-
My invention has for its object to provide certain improvements in holders for
incandescent electric lamps as hereafter described. I will describe my invention as
applied to so called bayonet socket holders and loop holders.
According to my invention I employ a collar piece to which a cylindrical base is
screwed, of slate, china or other non-conductor of electricity. The said base is
drilled with two holes on one diameter. Into these holes the contact pieces can be
slidden. These said contact pieces consist, in a bayonet socket holder, of a screw
and washer for holding the external wires, the contacts with the cap on the lamp
being made preferably by a plunger. In a loop holder instead of a plunger a spiral
spring terminating in a hook is employed. The holes in the insulating base are
enlarged at the top to allow screws and washers to enter to a depth so that the top
of the screws are a little below the surface of the base after the external wire is
inserted in the said screw.
On the side of each enlarged hole is provided a groove in which the external wire
The entire contact
is placed after leaving the bottom of the head of the screw.
pieces can be taken out of the base for case in fixing the external wires. The head
of the screw is thus entirely beneath the surface of the base rendering it impossible
for the two external wires to touch each other. In order that the two external
wires may be firmly clamped to the holder I employ a circular disc of india rubber,
leather, or other clastic non-conductor of electricity. This disc has a small hole in
the centre through which the external wires pass. The disc is clamped down on the
top of the base by means of the part which forms the top of the holder and
which is capable of being screwed down over the collar. Thus the length of each
external wire which runs horizontally from the groove made in the enlarged
part of each hole in the base along the surface of the base to the hole in
the disc is clamped tightly between the top surface of the insulating base and
the bottom surface of the disc thus relieving the joint made at the screws from any
strain.
יה
ليم
1
1
1000
COMPLETE SPECIFICATION.
Improvements in Holders for Incandescent Electric Lamps.
I, EDWIN PERCIVAL ALLAM, of Elm Bank, Romford in the County of Essex,
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 :-
My invention has for its object to provide certain improvements in holders for
incandescent electric lamps as hereafter described, and the same will be best
understood by describing the invention with reference to the accompanying
drawings wherein
Figure represents a vertical section of a so called bayonet socket holder
constructed according to my invention.

page_text: Figure 2 represents a vertical section of a so called loop holder constructed
according to my invention;
Figure 3 is a plan of Figures 1 and 2 taken at the line A B and for the sake of
showing the holders clearly they are drawn on a somewhat larger scale than they
would be usually made.
On
According to my invention I employ a collar piece a to which is screwed the
cylindrical base 6 of slate, china, or other non-conductor of electricity. The said
base is drilled with two holes on one diameter. Into these holes can be slidden
the contact pieces c¹². These said contact pieces consist (in a bayonet socket
holder) of a screw and washer d' d for holding the external wires, the contacts with
the cap on the lamp being made preferably by a plunger as at e¹ e². In a loop
holder instead of a plunger a spiral spring terminating in a hook is employed. The
holes in the insulating base are enlarged at the top to allow the screws and
washers and d² to enter to a depth so that the top of the screws are a little below
the surface of the base after the external wire is inserted in the said screw.
the side of each enlarged hole is provided a groove Figure 3 in which the external
wire is placed after leaving the bottom of the head of the screw. I make no claim
as to the construction of these contact pieces, my improvement consisting of the
arrangement shown whereby the entire contact pieces can be taken out of the base
for ease in fixing the external wires and whereby the head of the screw is entirely
beneath the surface of the base b, thus rendering it impossible for the two external
wires to touch each other. In order that the two external wires may be firmly
clamped to the holder I employ a circular disc of india rubber, leather, or other
elastic non-conductor of electricity as shown at y Figures 1 and 2. This disc has a
small hole in the centre through which the external wires pass. The disc y is
clamped down on the top of the base by means of the part which forms the top
of the holder and which is capable of being screwed down over the collar. Thus
the length of each external wire which runs horizontally from the groove, made in the
enlarged part of each hole in the base b, along the surface of the base to the hole
in the disc y is clamped tightly between the top surface of the insulating base
and the bottom surface of the discy thus relieving the joint made at the screws from
any strain.
Having now particularly described and ascertained the nature of my said inven-
tion and the manner in which the same is to be performed I declare that what I
claim is :-
:
First The improved holders for incandescent electric lamps consisting of
the parts as hereinbefore described and illustrated by the accompanying
drawings.
Second: In holders for incandescent clectric lamps, the means described and
illustrated in the accompanying drawings, whereby the contact pieces with their
screws and washers can be taken away from the rest of the holder for case in
affixing the external wires.
Third: In holders for incandescent electric lamps, the means described and
illustrated in the accompanying drawings, whereby the screws and washers for
affixing the external wires are arranged beneath the surface of the insulating base
of the said holder.
Fourth In holders for incandescent electric lamps the means described and
illustrated in the accompanying drawings whereby the external wires are clamped
to the said holder.
1 1
1 1
1001
Witness-
E. G. BREWER,
33, Chancery Lane, London.
EDWIN PERCIVAL ALLAM.