Improvements in Lamps.
Year: 1898

page_text: Date of Application, 31st May, 1898-Accepted, 1st Oct.,
1898
COMPLETE SPECIFICATION.
Improvements in Lamps.
1, CHARLES LANCASTER MARSHALL, of 879, Mount Prospect Avenue, Newark,
Essex County, New Jersey, United States of America, Manufacturer, do hereby
declare the nature of this invention and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:
This invention relates generally to lamps, and particularly to oil or spirit lamps
of that class which produce light through the heating to incandescence of a suit-
able refractory body, such as a gauze mantle of refractory material. The lamp
herein described is particularly adapted for the use of petroleum or kerosene oil,
though it may also use more valatile oils, such as naphtha' or may use spirits, such
as alcohol.
The objects of the invention are, first, to provide an improved burner for oil.
and spirit lamps, adapted for heating a suitable refractory mantle to incandescence
and by which a light of great intensity may be produced, without smoking of
the mantle, or the production of noise by the lamp, and which is simple and com-
paratively inexpensive in construction, and easily operated; second, to provide
a lamp of the above class so designed and constructed that when the lamp is
lighted, the change from the yellow or luminous flame, produced when the lamp
is first lighted, to the non-luminous flame, takes place very quickly and may be
made to take place automatically third, to prevent distrubance of the lamp when
in operation by wind or external air draughts; fourth, to provide an improved
gasifier for the lamp; fifth, to provide improved means for protecting the mantle
from injury when the draft chimney is being removed and replaced, and for
protecting the draft chimney against breakage by the heat produced by the
burner; and sixth, to provide an improved mantle supporting and adjusting
device.
:
These objects are attained in the improved lamp herein described and illus-
trated in the drawings which accompany and form a part of this specification, in
which the same reference numerals indicate the same or corresponding parts, and
in which
Figure 1 is an elevation of a complete oil lamp embodying my invention;
Figure 2 is a central vertical section of the burner of the lamp;
Figure 3 is a detail side elevation of the mantle supporting and adjusting device;
Figure 4 is a detail elevation and partial section of one form of gasifier; and
Figures 5 and 6 are similar views of other forms of gasifiers which may be
used instead of the form shown in Figure 4.
In lamps of the class to which this invention relates, and which are particularly
adapted for burning petroleum or kerosene oil, with a blue or colorless flame of
great heating power, the wick tube of the burner is surrounded by a casing or
skirt, into which, as well as into a central draught tube, air is admitted. The
air currents rising through the skirt are concentrated, at a point at or near the

page_text: with considerable accuracy, so that little or no bending of the rod 11 to perfect
the adjustment is necessary.
Air is admitted to the burner at two points, viz., at the mouth of the draft
tube 2, in the base of the lamp, and at the bottom of the skirt 4 of the burner,
through openings in a bead 14, provided for that purpose.. The skirt 4 is imper-
forate, except in its extreme lower portion, so that air entering the burner through
the openings in the skirt become vertical currents before they can influence the
flame in any way. In this manner, disturbance of the action of the lamp by
external air draughts is avoided. The use of a skirt or outer casing provided with
air openings in its lower part only, well away from the flame, instead of with
perforations close to the chimney gallery as has been the case in most lamps
heretofore used, is an important feature of the invention, as the flame is steadier,
the heat more intense, and the tendency of the flame to go back to the luminous
condition temporarily, when a current of air strikes the lamp suddenly, (a serious
fault of the former lamps of this class,) is avoided.
Most of the air entering the openings in the lower end of the skirt 4 passes up
through the interior of the draft collar 5, but some of the air passes through a series
of perforations in the draft collar, where it divides, one current passing between
the draft collar and the ring 9, and the other passing between the ring 9 and
chimney 7. These air currents serve to prevent overheating of the ring 9 and
chimney 7, and the current of air passing between the draft collar and the ring 9
also assists, to some extent, to produce complete combustion with the non-
luminous flame."
Instead of providing perforations in the draft collar 5, as illustrated in Figure 2,
and as above described, the chimney gallery 15 may be perforated below the
chimney 7 but above the lower out-turned flange of the draft collar. But I find
that it is preferable to take the air which prevents overheating of the ring 9 and
chimney 7, from the interior of the skirt 4, as a more intense flame is thereby
produced and a shorter chimney may be used.
Another important feature of the invention is the method of connecting the
chimney gallery 15 and draft collar 5 to the skirt 4, as thereby the use of soldered,
brazed, or riveted joints is avoided. The chimney gallery 15 is provided, at its
bottom, with an outwardly extending flange, which is bent over a corresponding
flange or bead upon the upper end of the skirt 4, and the parts pressed together.
The draft collar 5 is provided with a similar outwardly extending flange, which
fits into a recess on the inside of the chimney gallery 15. A locking ring 16
fits into a similar recess on the inside of the skirt 4, beneath the draft collar, and
the width of this locking ring 16 is such that it must be pressed into place, and
when in place presses the flange of the draft collar 5 tightly against the
chimney gallery 15. Friction and pressure then hold all of the parts locked
together firmly.
The skirt 4 is connected to-a' nipple: 13, by means of a bayonet catch, one pin 12
of which is shown in Figure 2, the said nipple screwing into the top of the oil
reservoir. By turning the skirt 4 until the catch is open, the skirt, with the
chimney and mantle, may be removed for the purpose of lighting, cleaning, or
trimming the lamp.
17
The operation of the lamp is as follows:
To light the lamp, the skirt 4, with the chimney and mantle, is first removed,
and the wick is adjusted so that it is somewhat above the top of the wick tube,
but is slightly below..its normal height, which is reached when the top of the
wick is about halfway between. the wick tube, and the flange 6 of the gasifier.
The wick is then lighted, and the skirt 4, with the chimney and mantle thereon,
is replaced, on the nipple 13. At first the lamp burns with a yellow or luminous
flame, but the flame is not high enough to smoke the mantle; but after a few
seconds have elapsed, so that the gasifier 6 and surrounding parts are well heated,
the wick is raised slightly. The flame then changes to the blue or colorless con-
dition, the combustible gases from the wick passing into the gasifier 6 through