Improved Method of Fitting the Covers of Electric Light Fittings to their Base Parts.
Year: 1899

page_text: Date of Application, 28th Dec., 1899
Complete Specification Left, 26th Sept., 1900-Accepted, 1st Dec., 1900
INVOVIDIONAL DIEUITIVATION.
Improved Method of Fitting the Covers of Electric Light Fittings
to their Base Parts.
ANDREAS PETER LUNDBERG and GUSTAF CHARLES LUNDBERG, both of Bradbury
Electrical Works, Bradbury Street, Kingsland, London, N., Electrical Engi
neers, do hereby declare the nature of this invention to be as follows:-
This invention relates to improvements in the fixing of covers of porcelain,
glass, wood, opal etc. of electric light switches, wall connections etc. to their
base parts. We take a circular ring of metal of suitable size, and turned over
at the edge for neatness, no ragged edge of metal being visible when the ring is
fitted in position. This turned over lip is continued in two or more narrow
prongs for the purpose of fixing
In the porcelain, wood or other cover it is desired to fit to a base part, we
provide a centre hole suitably shaped to take the pronged ring, and round the
circumference of such hole, we provide two or more slots or holes corresponding
with the number of prongs on the metal ring.
The metal ring is then inserted and the prongs pushed through their respective
holes or slots, the ring being fixed to the cover by the prongs being bent over
on the inside, the result being a very neat, strong and satisfactory job. The
method of fitting and the springy nature of the metal prongs, reduces to a great
extent the possibility of strain being produced and consequent cracking when
fitted to covers of procelain or similar material, caused by expansion of the metal
in a different degree to the material it is fitted into, by rise of temperature.
A screw thread for attachment to the base part is provided on either the out-
side or inside surface of the ring as desired, and the prongs prevent any
possibility of it turning round independently of the cover.
Dated this 28th day of December 1800
ANDREAS PETER LUNDBERG.
GUSTAF CHARLES LUNDBERG.
Improved Method of Fitting the Covers of Electric Light Fittings
to their Base Parts.
We, ANDREAS PETER LUNDBERG and GUSTAF CHARLES LUNDBERG, both of
Bradbury Electrical Works, Bradbury Street, Kingsland, in the County of
Middlesex, Electrical Engineers, do hereby declare the nature of this invention,
[Pain Q71

page_text: 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 improvements in the fixing of covers of porcelain,
glass, wood, opal etc. of electric light switches, wall connections etc. to their
base parts.
And in order that our invention may be thoroughly understood, we now pro-
ceed to describe the accompanying drawing thereof, reference being had to
letters and figures marked thereon.
Fig. 1, is a plan of the top of cover with the ring fitted thereto.
Fig. 2, is a view of the inside of the cover...
Fig. 3, is a part in section and a part in elevation of the ring before it is
fixed to the cover.
Fig. 4, is a part in section and a part in elevation of the ring and cover.
Fig. 5, is a plan of the bottom of the ring before it is fixed to the cover.
We take a circular ring a of metal of suitable size, and turned over at the
edge c for neatness, no ragged edge of metal being visible when the ring a is
fitted in position. This turned over lip is continued in two or more narrow
prongs for the purpose of fixing.
In the porcelain, wood or other cover it is desired to fit to a base part, we pro-
vide a centre hole e with a flange e¹ on which the edge c of the ring rest suitably
shaped to take the pronged ring, and round the circumference of such hole we
provide two or more slots for holes corresponding with the number of prongs d
on the metal ring a.
The metal ring is then inserted and the prongs & pushed through their
respective holes or slots f and clinched to the inside of the cover the ring being
fixed to the cover by the prongs & being bent over or clinched on the inside as
in Fig's. 2, and 4, the result being a very neat, strong and satisfactory job.
The method of fitting and the springy nature of the metal prongs, reduces to
a great extent the possibility of strain being produced and consequent cracking
when fitted to covers of porcelain or similar material, caused by expansion of
the metal in a different degree to the material it is fitted into, by rise of tem-
perature.
A screw thread for attachment to the base part is provided on the inside
surface of the ring as desired, and the prongs prevent any possibility of it turn-
ing round independently of the cover.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what
we claim is :-
=
1. The method of fixing the covers of electric light fittings to their base parts,
substantially as above described.
2. The ring fitted to a cover for electric light fittings, substantially as above
described and according to the accompanying drawing.
"
3. In electric light fittings, the combination and arrangement of the ring
edge prongs d and screwed thread g, substantially as herein described and
according to the accompanying drawing.
4. In electric light fittings, the combination and arrangement of the clenched
prongs of the ring and the slots in the cover, substantially as herein described
and according to the accompanying drawing.
Dated this 26th day of September 1900.
J. P. BAYLY,
18, Fulham Place, London, W., Agent for the Applicants.