Improvements in Holders for Incandescent Electric Lamps.
Year: 1891

page_text: Date of Application, 4th Apr., 1891
Complete Specification Left, 29th Dec., 1891--Accepted, 30th Jan., 1892
PROVISIONAL SPECIFICATION.
Improvements in Holders for Incandescent Electric Lamps.
We, WILLIAM MCGEOCH, Junior, and ANDREW JACKSON MCGEOCH, of
108, Argyle Street, Glasgow, in the County of Lanark, North Britain, Electrical
Engineers, do hereby declare the nature of this invention to be as follows, that is
to say:
Our said invention has for its object, the constructing and combining of the
parts of holders for electric incandescent lamps in an improved manner, and
especially so that the "wiring" or attachment of the electric conducting wires
may be effected with facility with certainty of insulation and in a satisfactory
manner.
In carrying out our invention according to one modification we employ a metal
shell or casing which may be like any suitable known kind comprising two parts
connected together by an external screw coupling ring or otherwise. In one part
of the casing there is fixed a small block of vulcanised fibre, or porcelain, or other
suitable non-conducting material, fitted with spring contact pins. In the other
part of the casing there is fitted a smaller non-conducting block or disk made with
two perforations through it for the ends of the conducting wires. The conducting
wires are threaded through the perforations and have their ends fixed upon the
inner side of the non-conducting disk by screws with or without small plates or
washers. The heads of the screws make contact with the spring pins hereinbefore
referred to when the two parts of the casing are screwed together. The non-
conducting disk and the non-conducting block are made one with a diametrical
rib and the other with a counterpart groove which engage with each other when
the parts are put together and prevent short circuiting by a wire end accidentally
getting across from one fixing screw to the other.
The spring contact pins in the non-conducting block may be of a kind in use,
but are by preference of an improved kind, each consisting of two headed pins
connected by a spring wire helix which is soldered to them.
According to another modification one end of each spring contact pin is screwed
to screw into the outer non-conducting disk and is made with a small washer to
serve for fixing and making contact with the conducting wire. In this modification
the spring contact pins are fixed to the outer disk and when the parts are put
together are entered through the holes in the inner non-conducting block.
separate screw may be used in each case to fix the end of the conducting
wire, and the spring contact pin may be fixed by screwing upon the head of such
screw.
A
The outer non-conducting disk or piece may project through the cover of
the shell and be itself directly fixed by screwing to the carrying bracket or
fittings.
Dated this Third day of April 1891.
EDMUND HUNT,
Applicants' Agent.
COMPLETE SPECIFICATION.
Improvements in Holders for Incandescent Electric Lamps.
We, WILLIAM MCGEOCH, Junior, and ANDREW JACKSON MCGEOCH of
108 Argyle Street Glasgow in the County of Lanark, North Britain, Electrical
Engineers, do hereby declare the nature of this invention and in what manner the
[Price 6d.]

page_text: same is to be performed, to be particularly described and ascertained in and by the
following statement :-
Our invention has for its object the constructing and combining of the parts of
holders for electric incandescent lamps in an improved manner, and especially so that
the wiring or attachment of the electric conducting wires may be effected with
certainty of insulation.
Reference to the accompanying drawings, in which like letters indicate like
parts, will assist in ascertaining how our invention is carried into practice.
We employ a metal shell or casing which may be like the known kind comprising
two parts A. and C connected together by an external screw coupling ring B, or in
any other suitable way. Into the part of the casing a block D of vulcanised
fibre, porcelain, or other suitable non-conducting material is fitted. This block D
has two perforations, F, F, through which the conducting wires are threaded and
their ends fixed upon the inner (having regard to its position in the holder) side of
the block by screws, S, S, with or without small plates or washers. A second
block, G, also made of suitable non-conducting material is fitted inside the part A
of the casing. Two cylindrical cavities, H, H, in block G fit over the screws S, S,
and are made of sufficient depth and width that each may hold one of the spring
pins E, E. These pins E, E, are shown in Fig. V. in the position they should be
in when the blocks are put together. The top of block G is perforated in two
places so as to connect with the cavities (as shown in the drawing Fig. VI.) and so
enable the spring pins to make contact with the lamp when in position on the top
of block G. When the two blocks, D and G, are in position and the two parts of
the casing screwed together the heads of the screws S, S, will make contact with
the spring pins E, E.
A rim or projection, R, round the lower part of block G is useful to keep the
block in position in part A. of the casing, which in its turn is enlarged at its lower
end so as to fit over this rim. For the same purpose of ensuring retention of the
blocks in their proper position a small groove cut on one side (and in corresponding
parts) of cach of the ends of the blocks, D and G, near where they meet is
desirable, so that a catch, T, on the rim of the part A of the casing may hold
therein. A diametrical rib, I, at the bottom of the block G which is made to fit
(and, when the parts are put together, to engage in) a counterpart groove, K, cut
on the upper side of the block D, between the screws, S, S, further assists to keep
the blocks in their proper position whilst it effectually prevents short circuiting by
a wire end or terminal getting across from one fixing screw to another or touching
the casing.
The spring contact pins may be of the kind generally used, but we prefer an
improved kind consisting of a headed pin soldered to a spring wire helix.
The lamp may be attached either to the casing as at present or directly to the
block by screwing or other suitable mode.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is:-
The method of insulating each of the terminals from one another and from
the casing of a holder for incandescent electric lamps substantially as above
described.
Dated this 20th day of Danish…. 1001
WILLIAM MCGEOCH, JUNR.
ANDREW JACKSON MCGEOCH.