IMPROVEMENTS IN LAMPS FOR BURNING MINERAL OILS
Year: 1885

page_text: I JOHN THOMAS of 567 Caledonian Road in the County of Middlesex Lamp
Manufacturer do hereby declare the nature of my Invention for "IMPROVEMENTS
IN LAMPS FOR BURNING MINERAL OILS," to be as follows:-
My invention relates to improvements in that class of lamps known as railway
carriage roof lamps, and has for its object the construction of the lamps in such a
imanner that they may be adapted to burn mineral oils with safety.
And my invention consists in the first place in causing a large current of air to
circulate through the lamp and around the burner in such a manner as to keep
them cool, and thereby also to keep the temperature of the oil contained in the
burner from rising to such a point that such oil may be likely to become
inflamed.
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In order to effect this I construct the lamp with an outer case or body of the usual
cylindrical form, such case or body carrying at its lower part a glass globe or dish
to surround the light as required.
•
Within the said outer case or body of the lamp I arrange another body or
chamber which supports above it the oil cistern or reservoir, and from the lower
end of which body or chamber air tubes are so arranged as to carry the burner
between them at their lower extremities. These tubes serve to convey air into
the burner in order to support combustion, and also by suitable apertures in the
lower ends of such tubes, the air is caused to circulate in the globe or dish around
the burner and thereby to keep it cool as required..
In the second place in order that the flame of the lamp may be prevented from
increasing in size, I cause the draught of air supplied. to the flame in order to
support combustion to increase in proportion as the heat in the lamp increases, in
the following manner.
I arrange a diaphragm or false bottom in the above mentioned inner body or
chamber of the lamp having perforations or apertures for the admission of air to
the burner. In the interior of the lamp compound metal bars are secured at one
of their ends, and these bars carry plates or covers at their other ends which close
the perforations or apertures in the diaphragm when the lamp is cold. As the
temperature of the lamp rises, these bars (owing to the unequal expansion of the
metals of which they are composed) are caused to become curved and their free
ends which carry the plates or covers are moved, thereby opening the perforations
.מ

page_text: or apertures in the diaphragm so as to allow of a larger volume of air being
admitted to the burner and the interior of the lamp for the purpose of keeping the
same cool.
In the third place my invention provides a means of overcoming the tendency
of the oil to overflow the burner owing to the too rapid supply of the same from
the oil cistern or.reservoir, and thus becoming an element of danger when mineral
oils are employed.
My improvement consists in the arrangement of the oil cistern or reservoir in
the following manner. The oil cistern or reservoir is composed of cells or chambers
connected-and communicating with each other as hereinafter stated, and preferably
of an annular form and situated within the outer cylindrical body of the lamp
around the chimney of the same.
The communication between the said cells or chambers is at the bottom of each
cell or chamber. In the first or supplying cell or chamber there is a suitable pipe
provided to convey the oil to the burner, in the next cell there is a pipe arranged
so as to convey air from the burner and thereby displace the oil contained in such
cell or chamber as required.
The two above mentioned cells or chambers are caused to communicate with
each other by means of a dip-pipe of a U shape, passing from the bottom of the
second to the bottom of the first cell or chamber. When the oil contained in the
first or supplying cell or chamber is exhausted more oil passes into it through
the dip-pipe from the second cell or chamber. On this second cell or chamber
becoming emptied of oil, the third cell communicating with it is opened and
supplies the oil through the two first cells to the burner in the manner above
stated, and each of the rest of the series of cells in turn is caused to replenish the
burner. The communications or apertures between the second and. third cells (and
also between the other cells to the last cell), are made in the separating walls or
partitions between such cells or chambers, preferably at the bottom corners, so that
no oil can leave a cell until the oil in the preceding cell has been so far exhausted
as to allow of the entry of air for displacement through the communicating apertures
formed in the bottom of the separating wall or partition.
A suitable aperture or opening for the purpose of filling the oil reservoir or
cistern is arranged in the side of the first or supply cell or chamber.
Lastly In order to keep and maintain a steady light when travelling at great
speed, I allow, the gaseous products of combustion to escape in a lateral direction
by means of a suitably arranged perforated metal cone at the upper end of the
chimney of the lamp, such cone being protected in any suitable manner from the
effects of draught and entrance of dust or rain.

page_text: I JOHN THOMAS of 567 Caledonian Road in the County of Middlesex, Lamp
Manufacturer do hereby declare the naturo 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 :-
My Invention relates to improvements in that class of lamps known as railway
carriage roof lamps, and has for its object the construction of the lamps in such a
manner that they may be adapted to burn mineral oils with safety,
And my invention consists in the first place in causing a large current of air to
circulate through the lamp and around the burner in such a manner as to keep
them cool, and thereby also to keep the temperature of the oil contained in the
burner from rising to such a point that such oil, may be likely to become
inflamed.
In the accompanying drawings Fig. 1 is an elevation and Fig. 2 a vertical
section of the lamp. A is the outer case or body of the lamp of the usual
cylindrical form, such case or body carrying at its lower part a glass globe or dish B
to surround the light as required.
Within the said outer case or body of the lamp I arrange another body. or
chamber C which supports above and around it the oil cistern or reservoir D, and
from the lower end of which body or chamber air tubes E aro so arranged as to
carry the burner F between them at their lower extremities. These tubes serve to
convey air into the burner in order to support combustion and also by suitable
apertures G in the lower ends of such tubes the air is caused to circulate in the
globe or dish around the burner and thereby to keep it cool as required.
In the second place in order that the flame of the lamp may be prevented from
increasing in size, I cause the draught of air supplied to the flame in order to
support combustion to increase in proportion as the heat in the lamp increases in
the following manner.
Referring to the section Fig. 2 H is a diaphragm or false bottom in the above
mentioned inner body or chamber of the lamp having perforations or apertures H¹
for the admission of air to the burner. In the interior of the lamp compound
metal bars I, I, are secured at one of their ends to the chimney and these bars
carry plates or covers J, J, at their other ends which close some of the perforations
or apertures in the diaphragm when the lamp is cold.-As the temperature of the
lamp rises these bars (owing to the unequal expansion of the metals of which they
are composed) are caused to become curved and their free ends which carry the
plates or covers are moved, thereby opening the perforations or apertures in the
diaphragm so as to allow of a larger volume of air being admitted to the burner
and the interior of the lamp for the purpose of keeping the same cool.
In the third place my Invention is intended to provide a means of overcoming
the tendency of the oil to overflow the burner, owing to the too rapid supply of the
same from the oil cistern or reservoir, and thus become an element of danger when
mineral oils are employed.
My improvement under this head consists in the arrangement of the oil cistern
or reservoir D in the following manner. This oil cistern or reservoir (shown in
horizontal section in Fig. 3 and vertical section in Fig. 4) is composed of cells or.
chambers connected and communicating with each other as hereinafter stated, and
is preferably of an annular form and situated within the outer cylindrical body of
the lamp and around the chimney of the same.

page_text: The communication between the said cells or chambers is at the bottom of each
cell or chamber as shewn at K in Fig. 4. In the first or supplying cell or
chamber L (Fig. 3) there is a suitable pipe M provided) to convey the oil to the
burner, in the next cell N there is a pipe O arranged so as to convey air from
the burner and thereby displace the oil contained in such cell or chamber as
required.
The two. above mentioned cells or chambers are caused to communicate with
each other by means of a dip pipe P of a U shape forming a communication
between the bottoms of the two cells L and N.
When the oil contained in the first or supplying cell or chamber L is exhausted
and the oil in the burner below is also exhausted, air can pass up the pipe O into
the cell or chamber N, which allows oil in the chamber N to pass by means of the
dip pipe P into the cell or chamber L and thence by the pipe M to the burner.
This continues until the oil in the burner rises and covers the end of the pipe O,
then as no more air can pass up the pipe O no more oil can pass out of the cell or
chamber N. This action is repeated until all the oil in the cell or chamber N is
exhausted. When this is the case, the air is free to enter the third cell or
chamber and so on throughout the series. The communications or apertures
between the cells or chambers are made in the separating walls or partitions
between such cells or chambers preferably at the bottom corners, so that no oil
can leave a cell until the oil in the preceding cell has been so far exhausted as to
allow of the entry of air for displacement through the communicating apertures
formed in the bottom of the separating wall or partition.
A suitable aperture or opening R for the purpose of filling the oil reservoir or
cistern is arranged in the side of the first or supply cell or chamber L.-The
reservoir or cistern to be filled must be turned over on to its side with tho
aperture R uppermost.
Lastly In order to keep and maintain a steady light when travelling at great
speed, I allow the gaseous products of combustion to escape in a lateral direction
by means of a suitably arranged perforated metal cone S (Fig. 2) at the upper end
of the chimney of the lamp, such cone being protected in any suitable manner from
the effects of draught and entrance of dust or rain,
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed declare that what
I claim is
First. The means described for keeping the burner cool by causing a current of
air to pass into the dish or globe independently of the air for supporting combustion
substantially as described.
Secondly. The arrangement for regulating the flame by means of expansion bars
in the manner substantially as described.
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Thirdly. The arrangement for preventing overflow of oil by means of the
reservoir and pipes shewn in Figures 3 and 4 substantially as described.
Fourthly. The arrangement of a perforated cone at the top of the chimney for
maintaining a steady light substantially as described..
And lastly. The general arrangement and combination of the several parts of
the lamp substantially as described.
Dated this 22nd day of January 1886