An Improvement in Railway Carriage Roof Lamps and an Improved Glass in Connection therewith.
Year: 1887

page_text: Date of Application, 16th Mar., 1887
Complete Left, 14th Dec., 1887
Complete Accepted, 20th Jan., 1888
An Improvement in Railway Carriage Roof Lamps and an Improved
Glass in Connection therewith.
I HENRY DEFRIES of 4 Cleveland Gardens, Hyde Park, London, in the County
of Middlesex, Gentleman, do hereby declare the nature of this invention to be as
follows:-
This Invention relates to an improvement in Railway Carriage Roof lamps
whereby the lamp glass will be less exposed to breakage than in the ordinary
construction of such lamps.
The glasses of railway Carriage roof lamps are usually made with an outwardly
projecting flange or lip for attachment to the lamp; this flange and the metal fixing
bead forming when combined a projecting ring on the exterior of the lamp which is
found very objectionable, inasmuch that when the lamp is being passed through the
roof of the Carriage this ring often strikes the edge or sides of the opening, the jar
thus given constantly resulting in the breakage of the lamp glass.
By my invention I entirely obviate this cause of breakage, as I leave no projection
on that part of the lamp which is to pass within the Carriage, and I obtain this even
surface by making my lamp glass with a groove or recess, forming a non projecting
bead at the top of the glass, in lieu of the ordinary outwardly projecting flange or
lip; and by slightly increasing the thickness of the glass immediately below the
groove I compensate for the increased thickness of the bead at the top of the lamp
glass when it is covered by the metal bead fixing it to the lamp.
J
I may obtain additional thickness of glass below the groove by a band of glass, or
by more metal at that point, as I may find most desirable; and further, I may have a
glass band, or an increased thickness of glass, inside behind the groove should I find
the glass weakened at that point.
A Lamp thus made offers no projection that can strike against the opening in the
roof of the Carriage while being passed through it, but presents a perfectly even
surface up to the actual seating or socketing flange.
Din Cinamik dav CAL 1007

page_text: I may obtain additional thickness of glass below the groove (F) by a band of glass
or by more metal at that point (see I Fig. 3) as I may find most desirable; and
further, I may have a glass bead, or an increased thickness of glass, inside behind the
groove should I find the glass weakened at that point.
A Lamp thus made offers no projection that can strike against the opening in the
roof of the carriage while being passed through it, but presents a perfectly even
surface up to the actual scating or socketing flange (H).
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 use of a Railway Carriage Roof lamp having the glass fixed to the lamp by
a non projecting bead substantially as described.
2. A Railway Carriage Roof lamp glass having the recess F and non projecting
bead G substantially as described.
3. A Railway carriage roof lamp glass having the recess F, non projecting bead G,
and increased thickness of metal at I substantially as described.
Dated this Fourteenth day of December 1887.