Improvements in or relating to Electric Incandescent Lamps.
Year: 1895

page_text: Improvements in or relating to Electric Incandescent Lamps.
A communication by FREDERICK ROBERTS POPE, of 5, Goltzinsstraat, Venloo,
in the Kingdom of Holland, Electrician.
I, AUGUSTUS EDWIN POPE, of Harley Buildings, Old Hall Street, in the City
of Liverpool, Electrician, do hereby declare the nature of this invention to be as
follows:-
Electric incandescent lamps at the present time are attached to their caps or
connections by means of plaster. Sometimes the lamp gets loose from the plaster,
and is then useless. In any case the caps are useless when the lamp is done, as the
cost of getting the plaster out exceeds the value of the cap. Now by this
invention I am enabled to use a cap a great number of times, and it is attached
much more easily, and by an ordinary workman, instead of having to be fixed at
the factory, and no plaster is used.
The invention practically consists in attaching the lamp by means of a screw or
bayonet joint or its equivalent, and then soldering, dinging, or otherwise fixing the
cap at this point. The lamp which has been forwarded to me by my brother in
Holland has shrunk or fastened on it a collar. This collar has a projecting flange
arranged roughly in a double screw form so that the two compressed-in projections
on the cap can pass through gaps in this flange, and be screwed along until they
wedge themselves tight between the glass and the screw-formed flange. The hole
in the cap now comes opposite part of the flange, a little solder is placed in
this hole, and the cap is irremovable without tools, but by melting the solder with
a hot iron can be immediately unscrewed again, and used for a fresh lamp. It is
obvious that a lamp might be used without any solder. In this case the screwed
flange could be formed in the glass itself. Further that almost any other form of
bayonet joint or screw, or its equivalent could be used in place of the flange, and
the two pins, or projections on the cap, thus a screw thread or flange could be on
the cap, and two pins project from the collar on the glass, and these pins when
they come opposite a hole in the cap could be soldered. Where glass projection
is used instead of a brass collar a cement not capable of softening with the heat.
of the lamp could be used instead of solder, or there could be a dinge in the glass,
and the cap could be pressed into it at this point. This plan however is not near
as good as the ones already described, and I merely mention it to show that the
fastening or locking can be made in a great number of ways.
Dated the 1st day of February 1895.
WM. P. THOMPSON & Co.,
Of 6 Lord Street, Liverpool, Patent Agents for the Applicant.

page_text: A communication by FREDERICK ROBERTS POPE, of 5 Goltzinsstraat, Venloo, in
the Kingdom of Holland, Electrician.
1, AUGUSTUS EDWIN POPE of Harley Buildings, Old Hall Street, in the City
of Liverpool, Electrician, 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 :-
Electric incandescent lamps at the present time have their caps attached to them
by means of plaster. Sometimes the lamp becomes loose from the plaster, and is
then valueless, in any case the caps and bulbs are useless when the lamp is done, as
the cost of extracting the plaster or removing the cap therefrom exceeds in value
the two materials when separated.
Now by this invention, I am enabled to use the caps and bulbs a great number of
times. By it the cap can also be attached much more easily and by an ordinary
workman instead of having to be fixed at the factory, and it has the further advan-
tage that no plaster is used.
The invention is best described by aid of the accompanying drawings, in which
Figure 1 is an elevation of a lamp, the lower part taken at a slight angle from
its axis;
Figure 2 a view of cap taken at a like angle,
Figure 3 sectional elevation of cap and lamp in position without the solder attached
but showing the hole through which the solder can be applied,
Figure 4 section of part of the cap showing one of the two pressed-in projec-
tions which alternate preferably at an angle of 120 degrees with the soldering
hole.
In these, A is the lamp body, B filament, C an annular flange fixed to the
lamp in its manufacture. This flange is bent out of shape in a screw form at two
different points, only one of which is shown distinctly in the drawings at D, the
other is at an angle thereto corresponding to the angle that two pressed out
projections G (hereafter described) make with each other. E E are two slots in
the flange corresponding in position and size to the two pins G. F is the cap
almost similar in all respects to the existing ones, but having an enlarged mouth to
admit the flange C. GG are two inwardly projecting pins formed by pressing
inward the substance of the cap. H soldering hole. II the ordinary pins used
for connecting the cap to the socket.
The mode of action is as follows:-
The lamp with its flange rigidly attached thereto is placed in the cap F, and
the cap is screwed round until the two projections G G, which have previously
entered the slots E, come against the bent-up portion D D₁ of the flange C, and
wedge themselves tight against the same, a little solder is then dropped into the
hole H which uniting with the flange C and the cap hold the latter perfectly firm
in place. By melting the solder with a hot iron the cap can be immediately
unscrewed. If however it be not required to fix the cap the flange D can be
moulded on the lamp itself. I do not however advise this arrangement as its cost
would probably be greater than forming the lamp with the glass flange while the
glass flange will not be nearly as effective, besides the difficulty of rigidly fixing it.
It is also obvious that by forming a continuation of the dange C slightly enlarged
and in box form it could be made to perform the further duty of a cap, but while
this is thoroughly practicable there are mechanical difficulties in the way, and I
merely mention it as a modification of my invention so as to prevent others hereafter
claiming it as an independent improvement on my said invention.

page_text: Having now particularly described and ascertained the nature of the said:
invention and in what manner the same is to be performed, as communicated
to me by my foreign correspondent, I declare that what I claim is :-
1. The combination with an incandescent lamp of a collar C and projecting
screw flange fixed thereon substantially as and for the purposes described.
2. The combination of the incandescent lamp A, the flange C fixed thereto,.
and a cap F having projections forming a bayonet joint with the flange of the said
collar, C, substantially as described.
3. The combination of the lamp A, the L flange C, bent-up portions D and
slots E with the cap F, and projections thereon G for the purposes herein
described.
4. The combination of the incandescent lamp A the flange C, the cap F with
interlocking projections on the said flange and a hole H, whereby the cap and flange
can be connected by soldering.
5. The combination of a lamp A having one or more projections thereon and
a cap having projections thereon and interlocking with the projections on the
lamp when the two are placed together and turned substantially as described.
6. An incandescent lamp having a metallic projection fixed thereto and a metallic
cap having a projection interlocking with the projection on the lamp in combination
with means for uniting the metal of the cap to the metal of the lamp by means of
solder, substantially as described.
7. As a new article of manufacture an incandescent lamp and its cap mechanically
joined and fixed up connections without solder.
1005
WM. P. THOMPSON & Co.,
Of Liverpool, Manchester, Birmingham, and London, Patent Agents..