Year: 1886

page_text: I, THOMAS COOPER John Thomas, of 5 Carlton Road, Hornsey, in the County
of Middlesex, Engineer, do hereby declare the nature of this invention to be as
follows:-
In some overhead lamps, such for examples, as are described in the specifications
of former Letters Patent respectively No. 3564, dated 16 August 1881, No. 4179,
dated 29 August 1883, No. 5415 dated 25 March 1884, and No. 1449, dated
2 February 1885, all granted to J. F. Shallis & myself, the burner or burners is or
are so situated that the flame or flames is or are surrounded by an opaque wall or a
reflector and the light has to be projected downward and laterally into the chamber
or place to be illuminated.
Now the object of this invention is to provide bowls for lamps of the kind in
question so formed as to aid in diffusing the light from such a lamp within a
railway carriage compartment or other place in a more efficient way than obtains
with bowls of ordinary forms. For this purpose portions of the bowl are made
inclined substantially as hereinafter described. As examples, several forms (each
susceptible of modification) are illustrated in the accompanying sheet of drawings.
Referring to Fig. 1, the wall A is inclined, that is to say, it resembles an
inverted hollow truncated cone, and the bottom B of the bowl is made with its
inner surface convex and its outer surface concave, the inner surface being cover d
with opal C.. Figure 2 illustrates a modification in which the wall A is in the
form of an inverted hollow truncated cone and the botton B is of hollow conical
shape partly covered at its inner surface with opal C.
In Fig. 3 the wall A is partly vertical and partly curved and a portion of the
bottom B is externally concave, whilst internally it is formed with annular
ridges a and channels b. The bowl illustrated in Figure 4 has a wall A resembling
an inverted hollow truncated cone with a flat bottom B covered with opal C.
Fig. 5 illustrates a modification in which the upper part of the wall A is in the
formn of an inverted hollow truncated coue, whilst the part that unites it to the
flat bottom B is curved. The illustrations above referred to are given with
the object of facilitating an understanding of the general nature of my invention,
and it is to be understood that other forms of bowls may be made with the walls
inclined or the bottoňus curved or inclined, or both, in accordance with my
invention, and with or without ridges and channels for the purpose referred to
above, and I would remark that I do not limit myself to the application of opal to
the forms illustrated; and, furthermore, that, in some cases, it may be dispensed
with in bowls of the forms in connection with which I have shown its application.

page_text: I, THOMAS COOPER JOHN THOMAS, of 5, Carlton Road, Hornsey, in the County
of Middlesex, Engineer, do hereby declare the nature of this invention and in
what manner the same is to be performed to be particularly described and ascer-
tained in and by the following statement :-
:
In some overhead lamps, such for examples, as are described in the specifications
of former Letters Patent respectively No. 3564, dated 16 August 1881 ; No. 4179
dated 29 August 1883; No. 5415 dated 25 March 1884; and No. 1449 dated
2 February 1885 all granted to J. F. Shallis and myself, the burner or burners is
or are so situated that the flame or flames is or are surrounded by an opaque wall
or a reflector and the light has to be projected downward and laterally into the
chamber or place to be illuminated.
Now the object of this invention is to provide bowls for lamps of the kind in
question so formed as to aid in diffusing the light from such a lamp within a
railway carriage compartment or other place in a more efficient way than obtains
with bowls of ordinary forms. For this purpose portions of the bowl are made
inclined substantially as hereinafter described. As examples, several forms (each
susceptible of modification) are illustrated in the accompanying two sheets of
drawings.
Referring to Fig. 1 the wall A is inclined that is to say it resembles an inverted
hollow truncated cone and the bottom B of the bowl is made with its inner surface
convex and its outer surface concave the inner surface being covered with opal C.
Figure 2 illustrates a modification in which the wall A is in the form of an inverted
hollow truncated cone and the bottom B is of hollow conical shape partly
covered at its inner surface with opal C.
In Fig. 3 the wall A is partly vertical and partly curved and a portion of the
bottom B is externally concave, whilst internally it is formed with annular
ridges a and chanuels b. The bowl illustrated in Figure 4 has a wall A resembling
an inverted hollow truncated cone with a flat bottom B covered with opal C.
Fig. 5 illustrates a modification in which the upper part of the wall A is in the
form of au inverted hollow truncated cone, whilst the part D that unites it to the
flat bottom B is curved.
Fig. 6 illustrates in vertical section another form of bowl shown applied to a part
of an overhead lamp of the kind hereinbefore mentioned.
The wall A of the bowl is in the form of an inverted hollow truncated cone as
in Figs. 1, 2, and 4 and is connected to the part B of the bottom by an annular
part of which a portion E has its upper and lower surfaces Hat and another
portion F has its upper and lower surfaces conoidal.
The illustrations above referred to are given with the object of facilitating an
understanding of my invention, but it is to be understood that other forms of
bowls (with or without opal) may be made with parts such as A Figs. 1, 2, 4, 5,
and 6, or such as B Figs. 2 and 6, or such as Bab Fig. 3, and in some cases,
opal may be dispensed with in bowls of the forms in connection with which I have
shown its application.
}

page_text: Having now particularly described and ascertained the nature of this inven-
tion, and in what manner the same is to be performed I declare that what
I claim is :-
1. A bowl for an overhead lamp formed with a part resembling an inverted
hollow truncated cone substantially such as A in Figs. 1, 2, 4, 5, and 6 of the
drawings annexed.
2. A bowl for an overhead lamp formed with a part resembling a hollow cone
substantially such as B in Figs. 2 and 6 of the drawings annexed.
3. A bowl for an overhead lamp formed with a bottom B made concave externally
and provided at its interior surface with annular ridges a and channels b sub-
stantially as described with reference to Fig. 3 of the drawings annexed.
4. Lamp bowls formed substantially as hereinabove described with reference
respectively to and shewn in Fig. 1, Fig. 2, Fig. 3, Fig. 4, Fig. 5 and Fig. 6 of the
drawings annexed.