Improved Bowl for Electric and Lamps
Year: 1895

page_text: Date of Application, 2nd Nov., 1895-Accepted, 1st Feb., 1896
Improved Bowl for Electric and
Lamps,
A communication from JOHN LAWRENCE SPINK, Miller, and THOMAS WALTER
HORN, Barrister-at-Law, both of Number 31 Yonge Street, in the City of
Toronto, in the County of York and Province of Ontario, Canada.
.
1, ALFRED JULIUS BOULT of 323 High Holborn, in the County of Middlesex,
Chartered Patent Agent, 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 :-
The object of the invention is to devise a bowl or globe for electric and other
lamps which will collect and diffuse all the light rays emitted, and it consists,
essentially, of a glass bowl shaped substantially like the half of a lemon and
having moulded thereon circular horizontal prismatic ribs adapted to either
refract or reflect the light of the lamp and of a curved reflector fitted to the
top of the bowl, the whole being constructed in detail substantially as hereinafter
described.
Figure 1, is an elevation, partly in section, of this improved globe.
Figure 2, is an enlarged sectional detail of a portion of the globe.
Figure 3, is a plan view of the globe, with the curved reflector partly
broken away.
In the drawings, like letters of reference indicate corresponding parts in the
different figures.
A, is a glass bowl or globe moulded in one piece and having a series of circular
horizontal prismatic ribs B, moulded on the outside thereof.
C, is a circular curved reflector fitted on the top of the bowl and having an
opening through the top to permit of the passage of the carbons of the lamp. The
bowl is preferably made substantially of the shape of a half lemon with a small
opening at the bottom, but although we consider the shape of bowl shown as
preferable, yet the curves of the lower portion might be varied considerably without
prejudicing the utility of the apparatus. The indispensable feature being, that the
bowl must not be contracted above its greatest diameter, as it would otherwise be
impossible to withdraw the plunger used in the process of moulding. The shape of
the prismatic ribs may also be widely varied, though we consider it preferable to
use them of such a shape that rays of light from the arc striking the inside of
the upper face of the prismatic ribs will be totally reflected in a downward
direction, as indicated in Fig. 1, while light striking the lower prismatic ribs of the
globe will be refracted and bent from its downward course slightly towards the
horizontal.
The bowl is preferably made with a smooth interior surface, and the prismatic
ribs outside. Although it is possible to mould a bowl ribbed on the inside or even
ribbed on both sides, yet the arrangement shown will be found preferable.
In the drawing, the upper face of each prismatic rib makes substantially an
angle of one hundred and five degrees to the straight side of the bowl, or to
a tangent to the curved portions, while the lower face similarly makes an angle.
of forty-five degrees.
Although we show and describe a bowl as being moulded of a perfect
circular form, yet it might also be made of a polygonal shape, and a large
measure of utility obtained.

page_text: For many years, various means have been tried for diffusing and tempering the
intense glare of an electric arc, but no thoroughly satisfactory solution of the
-difficulty has yet been attained. Frosted and colored glasses absorb so much
light that they are useless where extensive illumination is required, but when my
improved bowl or globe is used, the rays proceeding from the arc are collected
and diffused in a horizontal and downward direction so as to not only give the
light much greater illuminating power, but also to so diffuse it that it may be looked
at without injury to the eye. As any rays not collected by the bowl are stopped
and reflected by the curved reflector on top, absolutely no light is wasted, and the
' utmost illuminating power is thus obtained from the lamp.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, as communicated to me
by my foreign correspondents we declare that what we claim is :-
1. As a new article of manufacture, a glass bowl or globe for electric and
other lamps moulded in one piece substantially of the shape of the half of a
lemon and having a series of circular horizontal prismatic ribs moulded thereon,
substantially as and for the purpose specified.
2. A glass bowl or globe for electric and other lamps of curved outline in
vertical section moulded in one piece and having a series of circular horizontal
prismatic ribs moulded thereon and shaped either to refract or reflect, substantially
as and for the purpose specified.
3. A glass bowl or globe for electric and other lamps moulded in one piece,
substantially of the shape of the half of a lemon, having a series of circular
horizontal prismatic ribs moulded thereon, in combination with a curved reflector
fitted to the top of the bowl, substantially as and for the purpose specified.
4. A glass bowl or globe for electric and other lamps, of curved outline moulded
in one piece with a large opening at the top and a small one at the bottom and
having a series of circular horizontal prismatic ribs moulded thereon, substantially
as and for the purpose specified.
5. A glass bowl or globe for electric and other lamps, moulded in one piece
substantially of the shape of the half of a lemon, having a series of circular
horizontal prismatic ribs moulded thereon, the upper face of each prismatic rib
being set at an angle of one hundred and five degrees to a tangent of the side of
the bowl, and the lower face similarly set at an angle of forty-five degrees,
substantially as and for the purpose specified.
6. A glass bowl or globe for electric and other lamps moulded in one or
more pieces, having a series of circular horizontal prismatic ribs moulded thereon,
the whole being bowl-shaped in vertical section, substantially as and for the
purpose specified.
Dated this 2nd day of November 1895.
BOULT & WADE,
Agents for the Applicant.