Year: 1897

page_text: I, GEORGE WILLIAM DE TUNZELMANN, Electrical Engineer, of 2 and 4 Penywern
Road, Earl's Court, London S.W. do hereby declare the nature of this invention to
be as follows:-
Whereas it is frequently desirable to be able to tilt a suspended incandescent lamp
furnished with a shade or reflector, at various angles in such a manner as to throw
the light in any required direction, I have devised a method of effecting this object
by simpler means than those hitherto in use for the purpose.
I rigidly attach to the lampholder, preferably in a plane at right angles to the axis
thereof and symmetrically to that axis, a platform carrying a shifting weight,
which latter, by being varied in position, alters the centre of gravity of the system
consisting of the lamps, the shade or reflector, and the platform with its shifting
weight, and causes the system to assume the required orientation or direction when
in equilibrium.
The method of carrying this into practice which I prefer, is to construct the
platform of a pair of saucer, shaped sheets of metal or other suitable material joined
together so as to form a closed surface, or the closed surface may be formed in any
other convenient manner.
I generally make the platform circular; but I do not confine myself to this form
and may make it of any other convenient shape.
The space within the closed surface is partly filled with some heavy substance in a
comparatively fine state of division. I find that shot, or shot mixed with sand are
suitable substances, but I do not confine myself to them.
It will then be found that the direction of the beam of light from the lamp can be
varied through a solid angle of considerable magnitude by simply placing the shade
or platform in the position required, which it will then maintain.
The upper and lower surfaces may, if preferred, consist of a pair of cones, and,
whether saucers or cones are employed, the lower surface may be either concave or
convex, the latter preferably when the weight is required to be as small as possible.
If the lower surface of the platform is concave it may then itself form the shade or
reflector, or it may be attached above the same.
Another method of carrying out my invention is to use a continuous or interrupted
tube partly filled with shot, shot and sand, or other suitable substance and rigidly
fixed to the lampholder, shade, or reflector, and preferably parallel to the lower edge
of the latter.
Another method again is to make the platform into a collar moveable about the
axis of the lampholder, and to which is attached a projecting arm carrying a weight,
the position of which on the projecting arm can be varied at will.
Dated this First day of January 1897.

page_text: An Improved Electric Light Fitting.
I, GEORGE WILLIAM DE TUNZELMANN 2 and 4 Penywern Road London, S.W.
Electrical Engineer, 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 :-
Whereas it is frequently desirable to be able to tilt a suspended incandescent
electric lamp furnished with a shade or reflector, at various angles in such a manner
as to throw the light in any required direction, I have devised a method for effecting
this object by simpler means than those hitherto in use for the purpose. I rigidly
attach to the lamp holder, preferably in a plane at right angles to the axis thereof,
and symmetrically to that axis, a platform carrying a shifting weight, which latter
'by being varied in position alters the centre of gravity of the system consisting of the
lamp, the shade or reflector and the platform with its shifting weights, and causes
the system to assume the desired orientation or direction when in equilibrium.
The method of carrying this into practice which I prefer, is to construct the
platform of a pair of saucer-shaped sheets of metal or other suitable material jointed
'together so. as to form a closed surface, or the closed surface may be formed in any
other convenient manner.
-
I generally make the platform circular, but I do not confine myself to this form,
and may make it in any other convenient shape.
The space within the closed surface is partly filled with some heavy substance in
a comparatively fine state of division. I find that shot, or shot mixed with sand, are
suitable substances, but I do not confine myself to them.
It will then be found that the direction of the beam of light from the lamp can be
varied through a solid angle of considerable magnitude, by simply placing the shade
or platform in the position required, which it will then maintain.
The upper and lower surfaces of such a platform may, if preferred, consist of a pair
of cones, and whether saucers or cones are employed, the lower surface may be either
concave or convex. The latter is preferable where the weight is required to be as
small as possible. If the lower surface of the platform is concave, it may then itself
form the shade or reflector, or it may be attached above the same.
Another method of carrying out my invention is to use a continuous or interrupted
tube partly filled with shot, shot and sand, or other suitable substance, and rigidly
fixed to the lampholder, shade or reflector, and preferably parallel to the lower edge
of the latter.
Another method again is to make the platform into a collar movable about the
axis of the lampholder, and to which is attached a projecting arm carrying a weight,
the position of which on the projecting arm can be varied at will.
For purposes of illustration, I will now refer to the annexed drawings which shew
a method of carrying out my invention.
Figure 1. is a sectional side elevation.
Figure 2. sectional side elevation in tipped position.
Figure 3. plan view.
The receptacle a contains an amount of shot, sand, or other movable counterpoising
substance, and the position of this substance in the receptacle will determine the
angle at which the lamp will hang. The substance is inserted in the receptacle or
platform by any convenient apertures such as shewn.
Although for purposes of illustration I have shewn one way in which I carry out
my invention, it will be obvious that there are various modifications as to the shape

page_text: of the receptacle or platform and the manner of carrying out the principle of my
invention. The platform or receptacle may be used as a reflector if desired.
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
1. An improved electric light fitting for the purpose of enabling the angle of hanging
lamps to be varied, consisting of a platform or receptacle_carrying a movable
counterpoise such as shot and sand for the purpose of enabling the angle of the lamp
to be varied according to the position of the movable counterpoise in the receptacle
or on the platform secured to said lamp.