An Improved Detachable Electric Lamp Jointing for Removable Lamps for Shop Fronts and similar situations.
Year: 1892

page_text: Date of Application, 3rd Oct., 1892-Accepted, 5th Nov., 1892
COMPLETE SPECIFICATION.
An Improved Detachable Electric Lamp Jointing for Removable
Lamps for Shop Fronts and similar situations.
I, WILLIAM RICHARD WYNNE of 72 Grey Street, in the City and County of
Newcastle-on-Tyne, 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 :-
This invention relates to an improved detachable electric lamp jointing for
removable lamps for shop fronts and similar situations.
As hitherto constructed the detachable jointing used in connection with outside
electric lamps has been very apt under certain circumstances to break contact and
to consequently extinguish the light in au intermittent fashion owing to the method
of construction employed and the present invention has for its object a detachable
jointing which shall be sufficiently rigid to prevent any such breakage of the
electrical contacts and at the same time admit of easy disconnection when such is
required.
will describe my invention in detail with reference to the accompanying
drawings in which
Figure 1 shows a front elevation, Figure 2 a side vertical sectional elevation
and Figure 3 a small scale general side elevation of my improved apparatus
and throughout the following description like marks of reference designate like
parts.
Referring to the drawings, a is a metal casing or bonnet designed to be per-
manently secured to the facial boarding above a shop window.
Secured within this casing is a plate a¹ of porcelain or other non-conducting
material.
The permanent electric mains or wires to are secured at a' and the current is
then free to pass on to the conductiug contact springs a.
Formed within the casing and on each side thereof, is an inclined groove 4,
and at its upper extremity each groove on either side of the casing is somewhat
enlarged and provided with a rest or bracket 5 for the lugs 6 hereinafter
mentioned.
These grooves serve as guides to two projecting lugs 6 formed on a separate
special casting 7.
The back of this casting is furnished with a door 8 secured to the casting by
screws and in the inside of this casting another porcelain or non-conducting plate 9
is fixed, to one side of which electrical contact surfaces 10 are screwed and on
the other side of which the insulated electric mains or wires w' are secured as
shown.
These wires are led down a pipe p, screwed into a boss in the casting, to the
electric lamp e.
It will be observed that the casting 7 with its door 8, plate 9 and its attachments
and pipe p forms of itself a piece of apparatus independent of the casting or
bonnet a but the inclination of the door 8 is designed to coincide with the
inclination of the front part of the casing a.
Thus when it is required to light the lamp e, the casting 7 is inserted within the
bonnet a and for this purpose it must be held at an inclination and the lugs 6 on
the casting must be slid up the grooves 4 until they reach the top thereof. The
bottom surfaces of the lugs can then be allowed to drop down into the bearings or
rests 5 and at the same time the casting 7 and its pipe p will gravitate into a
vertical position and the contact springs a will then be pressed against the contact
rn

page_text: surfaces 10 whereby the current from wires w will be enabled to pass to wires to
and so to light the lamp e.
When it is required to remove the lamp, the attendant firstly slightly lifts up
the casting 7 by means for instance of the pipe as a handle and then inclines it
until the lugs 6 are in a position to freely descend the grooves 4. The piece 7 and
its appurtenances can then be easily withdrawn from the bonnet a.
In this manner detachment and replacement is easily effected, and the method
described of attachment of the parts effectually prohibits any intermittent
extinguishing of the light which has hitherto been a source of considerable
inconvenience.
The bonnet or the detachable portion or both may if desirable be provided with
any ordinary means for the prevention of short-circuiting, e.g. by the provision of
fusible strips or wires.
In the drawing represents a reflector to throw the light onto the required
surface, F a facial board, m a moulding and g a window glass.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :
1. The improved detachable electric lamp jointing consisting in the use of a
bonnet containing internal lateral grooves terminating at their upper extremities in
rests or brackets and a separate casting or piece of apparatus furnished with lateral
lugs designed to slide up and down the said grooves and to rest in the said rests or
brackets, the said bonnet and the said separate casting or piece of apparatus being
provided respectively with electrical contact media for the purpose of conveying
or breaking the electric current between the lamp and the generating station, the
several parts being arranged and designed to operate substantially in the manner
and for the purposes herein set forth.
2. The detachable electric lamp jointing for shop-front and similar lamps
consisting in the novel arrangement of grooved bonnet in conjunction with the
detachable casting 7, the latter being designed to enter and assume a practically
rigid position within the bonnet while the lamp is in action and to be readily
detached therefrom by slightly raising it then inclining it and then lowering it the
several parts being arranged and designed to operate substantially as and for the
purposes set forth.
Dated thie 30th day of Sontombar 1802
A. CRAWHALL CHAPMAN,
3, St. Nicholas Buildings, Newcastle-on-Tyne, Patent Agent.