Improvements in the Bulbs of Electric Incandescent Lamps.
Year: 1898

page_text: Improvements in the Bulbs of Electric Incandescent Lamps.
I, CURT BARTENSTEIN, of 27, Skalitzerstrasse, Berlin, in the Empire of Germany,
Manufacturer, do hereby declare the nature of this invention to be as follows:-
This invention relates to improvements in bulbs for electric incandescent lamps,
which bulbs are provided with peculiar grooves, ridges or ribs for the purpose of
obtaining a higher illuminating effect.
In contradistinction to previous arrangements of ridges or ribs, applied to lamp-
bulbs solely for decorative purposes the ridges, grooves or ribs, forming the subject
of this invention are so arranged, as to produce an intense reflection upon each
other. As a matter of fact, most of the rays produced in ordinary bulbs of electric
incandescent lamps pass vertically to the direction of the filaments, whilst the
latter, seen from the side, cover each other, thus causing an uneven distribution
of the rays, which produces a disagreeable sensation upon the eye of the spectator.
This defect is completely removed by the device forming the subject of this
invention. According to the latter, the rays are reflected in opposite directions
to that of the longitudinal grooves, ridges or ribs, whereby a more intense illu-
minating effect is produced.
In carrying my invention into practice the stem is joined to the bulb proper
which latter is formed of preferably double cone shape. In this bulb the grooves,
ridges or ribs reflecting the light in opposite directions are provided. These
strongly pronounced grooves, ridges or ribs may be produced by melting.
According to this invention the shape chosen in each case is of course, not of so
much importance as the fact, that the bulbs, provided with longitudinal grooves,
ridges or ribs, are so shaped as to produce and facilitate the reflecting effect in
opposite directions.
Dated this 14th day of Sentember 1898
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.
CURT BARTENSTEIN, of 27, Skalitzerstrasse. Beslin, in the Empire of Germany,
Manufacturer, do hereby declare the nature of this invention, and in what manner
the same is to be performed, to be particularly described in and by the following
statement:
This invention relates to improvements in bulbs for electric incandescent lamps,

page_text: which bulbs are provided with peculiar grooves, ridges or ribs for the purpose of
obtaining a higher illuminating effect.
In contradistinction to previous arrangements of ridges or ribs, applied to lamp-
bulbs solely for decorative purposes, the ridges, grooves or ribs, forming the subject
of this invention are so arranged, as to produce an intense reflection upon each
other.
As a matter of fact, most of the rays produced in ordinary bulbs of electric
incandescent lamps pass vertically to the direction of the filaments, whilst the
latter, seen from the side, cover each other, thus causing an uneven distribution
of the rays, which produces a disagreeable sensation upon the eye of the spectator.
This defect is completely removed by the device formed the subject of this inven-
tion. According to the latter, the rays are reflected by the longitudinal grooves,
ridges or ribs in opposite directions whereby a more intense illuminating effect
is produced.
In the accompanying drawing;-
Figure 1 represents a mushroom-shaped bulb in elevation; and
Figure 2 is a section through the bulb on the line of Figure 1.
In carrying my invention into practice the stem a is joined to the bulb b proper
which latter is preferably formed of double cone shape. In this bulb b the grooves,
ridges, or ribs c, reflecting the light in opposite directions are provided. These
strongly pronounced grooves ridges or ribs may be produced by melting, and cor-
respond in size to those represented in Figure 2.
Instead of the form shown in full lines in Figure 1 the bulb of the incandescent
lamps may, if desired, have the shape shown by dotted lines, the chief objects
being to provide the bulbs with longitudinal ridges or ribs and to give them such
a form as to produce and assist in mutual reflection.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:
A bulb for electric incandescent lamps, provided with strongly pronounced longi-
tudinal grooves, ridges or ribs, produced by melting, which said grooves, ridges
or ribs, on imparting to the bulb a suitable shape (for instance a flattened, a
biconical or mushroom-shape) produce an opposite reflection, thereby yielding a
more intense illuminating effect.
Thin 91 Joy of Ta
1800
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.