Improvements in Railway Carriage Roof Lamps and the like.
Year: 1889

page_text: Date of Application, 19th Sept., 1889
Complete Specification Left, 18th June, 1890-Accepted, 19th July, 1890
PROVISIONAL SPECIFICATION.
Improvements in Railway Carriage Roof Lamps and the like.
I, WILLIAM DEATHRIDGE, of No. 10, Pleasant Terrace, Mary Street, Balsall
Heath, Worcestershire, Lamp Maker, do hereby declare the nature of this invention
to be as follows:-
This invention consists of the herein described improvements in those roof lamps
for railway carriages and train cars which burn mineral oils.
For the purposes of my invention I employ an outer metal casing provided with a
lower inverted dome-shaped glass as at present. Inside the outer casing, and
preferably resting on the top of the glass, is a horizontal partition which is concave
underneath and serves as a reflector, and from this horizontal partition is suspended
a small vessel carrying the lamp wick and burner the said lamp wick and burner
being of any ordinary kind. Suitable small holes are provided in the said horizontal
partition through which air passes down to the flame. In the centre of the said
horizontal partition is an opening and around this opening is a chimney carried
upwardly into the upper part of the lamp casing. The said vessel carrying the lamp
wick and burner is supplied with oil by a tube leading from a reservoir outside the
lamp this reservoir being preferably of annular form supported on the top of the lamp
and encircling the central part of the same so as to allow a current of air all round
the reservoir and prevent as far as possible its becoming heated. The tube from the
internal oil vessel rises up to, or almost to, the oil reservoir and in this tube is a
smaller tube provided with a tap which is secured to the underside of the oil reservoir
this smaller internal tube being carried down to about the required level of the oil in
the vessel to which the wick and burner are fixed. The said annular reservoir is
preferably partly filled by a ring of cork, wood, or other suitable substance so as to
prevent the mineral oil contained therein from swimming about when the lamp is in
notion; this ring of cork, wood, or other suitable substance is preferably fixed upon
the bottom of the reservoir so as to allow the oil to flow very slowly through the
said small outlet tube to the said vessel inside the inverted glass dome. A suitable
filling hole provided with a screwed plug or other means is provided on the top of the
oil-reservoir. A small pipe is carried from near the top of the vessel to which the
lamp wick and burner are fixed through the horizontal partition so as to carry off any
vapours that may be formed in the said vessel and in the said vessel are also provided
one or more overflow pipes a certain distance below the top of the vessel these over-
flow pipes communicating with the bottom of the vessel so that if the oil in the vessel
should rise too high it will overflow through the said pipes into the inverted domė
shaped glass of the lamp.
When the said external oil reservoir is filled with the mineral oil and the inlet
closed by the screwed plug or other means so as to make the vessel air tight, the tap
in the outlet pipe is opened and the oil will flow down into the said vessel in the glass
dome and rise therein to a certain distance, its height being regulated as before stated
by the length of the internal outlet tube from the oil reservoir, and by the cork.or
other substance inside the annular vessel which by partly closing the outlet causes
the oil to flow out very slowly as it is consumed by the wick.
Dated this 18th day of September 1889.
CHARLES BOSWORTH KETLEY,
Agent for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in Railway Carriage Roof Lamps and the like.
I, WILLIAM DEATHRIDGE, of No. 10, Pleasant Terrace, Mary Street, Balsall
Heath, Worcestershire, Lamp Maker, 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 consists of the herein described improvements in those roof lamps
for railway carriages and tram cars which burn inineral oils, the object being to
minimise the risk of explosions therefrom and to render the parts more readily
accessible for cleaning etc.
On the accompanying drawing Fig. 1 represents in sectional elevation a railway
carriage roof lamp with my invention applied; Fig. 2 is a sectional elevation and
Fig. 3a plan of the removable partition of the same carrying tho small oil vessel and
the wick and burner; Fig. 4 represents in sectional elevation and plan the said small
oil vessel separately; and Fig. 5 is a sectional elevation and Fig. 6 a plan of the oil
reservoir and feeding tube of the said lamp separately.
The same letters of reference indicate the same or corresponding parts in all the
Figures of the drawing.
For the purposes of my invention I employ an outer metal casing a having an
ordinary lid and lower inverted dome-shaped glass c as at present. Inside the
casing a and preferably resting on the top of the glass c is the usual horizontal
partition which is concave underneath and serves as a reflector, and from this
horizontal partition is suspended by the pipes e and the small vessel g carrying the
lamp wick and burner i tho said lamp wick and burner being of any ordinary kind.
Suitable small holes are as usual provided in the horizontal partition d through
which air passes down to the flame. In the centre of the horizontal partition d is the
usual opening d¹ and chimney d carried upwardly into the upper part of the lamp
casing. The small vessel g carrying the lamp wick and burner is supplied with oil by
a tube leading from the reservoir outside the lamp this reservoir being preferably
of annular form as shewn and supported on the top of the lamp and encircling the
central part of the same so as to allow a current of air all round the reservoir and
prevent as far as possible its becoming heated. The tube from the internal oil
vessel grises almost up to the oil reservoir, (the top being just inside the cover of
the lamp) and in this tube f is a smaller tubes provided with a tap which is secured
to the underside of the oil reservoir k. The smaller tube s is carried down to about
the required level of the oil in the vessel g and its lower end is diminished in size to
quite a small aperture so as to check the flow of the oil. The annular reservoir k is
preferably partly filled by a ring m of cork, wood, or other suitable substance so as
to prevent the mineral oil contained therein from swimming about when the lamp is
in motion this ring m is preferably fixed against the bottom of the reservoir by
pegs n above so as to partly close the top of the tubes and cause the oil to flow very
slowly therethrough to the vessel y. A suitable filling hole provided with a screwed
plug o or other means is provided on the top of the oil reservoir. A small pipe e
is carried from near the top of the small vessel g through the partition d so as to
carry off any vapours that may be formed in the vessel g and in this vessel are also
provided one or more overflow or air pipes 'q'a certain distance below the top of
the vessel these overflow pipes communicating with the bottom of the vessel so that
if the oil in the vessel should rise too high it will overflow through these pipes g' q²
into the inverted dome shaped glass of the lamp. The pipes g¹g also admit air on
to the top of the oil in the vessel g which. passes out through the pipe e and keeps
the oil cool.
The boss on the oil vessel & into which the plug o is screwed projects at p for about
an eight of an inch more or less into the reservoir k so as to prevent the reservoir
being quite filled and ensure certain air space, otherwise the oil would not flow
down the vive s.

page_text: When the external oil reservoir is filled with the mineral oil to the level indicated
and the inlet closed by the screwed plug o so as to prevent any more air entering the
vessel, the tap in the ontlet pipe is opened and the oil will flow down into the
vessel in the glass doure and rise therein to a certain distance, its height being
regulated as before stated by the length of the internal outlet tube from the oil
reservoir, and by the cork or other substance m inside the annular vessel which by
partly closing the outlet causes the oil to flow out very slowly as it is consumed by
the wick.
It will be seen that the oil reservoir k and its tubes are entirely separate from the
lamp body so that they can be removed by simply being lifted off the same and as
readily replaced. In this example the reservoir k is supported in position by a
dished flange 2 just below the cock resting upon a corresponding projecting part b
on the top of the lid and by the reservoir resting upon two inclined projecting parts &
on the lid only one of which is shewn in the drawing.
As when the lamp is burning air circulates freely round the reservoir / and over
the oil in the vessel g, the oil is kept cool and any risk of explosion is avoided.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, 1 declare that what I
claim is:
-
1. In a mineral oil lamp of the kind herein described for the roofs of railway
carriages tramcars and for other like uses, the construction and arrangement of the
outside oil reservoir and its accessories and the pipes and s for the purposes and
substantially as herein before set forth and illustrated by the accompanying drawing.
2. In a mineral oil lamp of the kind herein described for the roofs of railway
carriages tramcars and for other like uses, the means herein described and illustrated
by the accompanying drawing for keeping cool the oil in the vessel g, consisting of
the pipes g', 2, or one or more of them supplying air to the top of the oil and the
pipe or pipes e for leading away any vapours in the vessel to above the partition d
substantially as hereinbefore set forth.
3 The combination and arrangement of parts constituting a mineral oil lamp for
the roofs of railway carriages tranicars and other like uses substantially as hereinbefore
described and illustrated by the accompanying drawing.
Dated this 16th day of June 1890.
CHARLES BOSWORTH AETLEY,
Agent for the Applicant.