Improvements in connection with Alternate Ourrent Aro Lamps and Lanterns,
Year: 1898

page_text: Date of Application, 24th Dec., 1898
Complete Specification Left, 22nd Sept., 1899-Accepted, 18th Nov., 1899
PROVISIONAL SPECIFICATION,
Improvements in connection with Alternate Ourrent Aro Lamps and
Lanterns,
We, WILLIAM MORRIS MORDEY, of 82, Victoria Street, in the City of West-
minster, Electrical Engineer, and HENRY BEVIS, of 71, Queen Victoria Street,
in the City of London, Electrical Engineer, do hereby declare the nature of this
invention to be as follows.
An objection to alternate current are lights arises from the noise they make
which 18 often sufficient to prevent their use for interior lighting
The object of this invention is to so suppress or reduce this noise as to remove
this objection.
We have found by experiment that this result can be attained by very simple
arrangements having for their object in the first place the prevention of tians-
mission of sound through air, and in the second place, the checking or damping
of sound vibration in the parts of the lamp, the globe, the case o lantern and
the supports We attain the first object by preventing, as far as is practicable,
all air communication between the arc itself, and the outer atmosphere. Where
complete closing in of the arc is not practicable, we restrict and lengthen or
muffle the air passages
The second object 18 attained by using anti-vibration
substances such as asbestos or rubber as supports, covers, or linings, for the
various parts of the lamp which are subject to or are capable of taking up and
tiansmitting the sound vibration The methods of carving out the invention
above set forth can be varied considerably with different kinds of lamps without
departing from the essential principles thereof. By systematically applying
these principles so far as the electrical and other conditions admit, to types o
forms of lamps, lanterns and projectors in common use, we are able to so reduce
the noise issuing from them that the present objection to their employment is
removed
COMPLETE SPECIFICATION
Improvements in connection with Alternate Ourrent Are Lamps and
Lanterns.
We, WILLLIM MORRIS MORDEY, of 82, Victoria Street, m the City of West-
minster, Electrical Engineer, and HENRY BEVIS, of 71, Queen Victoria Sucet,
[Price 8d 1

page_text: in the City of London, 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:--
An objection to alternate current arc lights arises from the noise they make
which is often sufficient to prevent their use for interior lighting
The object of this invention is to so suppress or reduce this noise as to remove
this objection
We have found by experiment that this result can be attained by very simple
arrangements having for their object in the first place the prevention of trans-
mission of sound through air, and in the second place the checking or damping
of sound vibration in the parts of the lamp, the globe, the case or lantern and
the supports. We attain the first object by preventing, as far as 18 practicable,
all air communication between the are itself, and the outer atmosphere Where
complete closing in of the arc is not practicable, we restrict and lengthen or
muffle the air passages
The second object is attained by using anti-vibration
substances such as asbestos or rubber as supports, covers, or linings, for the
various parts of the lamp which are subject to or are capable of taking up and
transmitting the sound vibration The methods of carrying out the invention
above set forth can be varied considerably with different kinds of lamps without
departing from the essential principles thereof By systematically applying
these principles so far as the electrical and other conditions admit, to types or
forms of lamps, lanterns and projectors in common use, we are able to so reduce
the noise 188uing from them that the present objection to their employment is
1emoved
In the accompanying illustrative drawings 18 shewn a projector for use in
stage lighting according to this invention
Fig 1 being a section on the line A B, Fig 2;
Fig 2 a plan, and
Fig 3 a section on the line C D, Fig. 2
The arc lamp 1 shown is of the hand regulating type, and has preferably
attached to the lower carbon holder 2 a globe 3, on the upper end of which rests
a cover 4, having a hole therethrough of sufficient size to allow the carbon 5 in
the upper carbon holder to move up or down as required The globe 3 with
its cover 4 acts to prevent, as far as practicable, air communication between the
are itself and the atmosphere
7 is a box oi casing, provided with a removable cover 8 formed with a longi-
tudinal slot fitted with a slide 8* to which the arc lamp 1 may be attached and
which can be adjusted so as to focus the arc; it is fixed in position by a set
screw 8b
The interior of this box or casing is lined with suitable materials,
such as iron, and asbestos in the form of sheets, the iron 9 being placed against,
or separated by an air space from the outer walls of the box casing, and the
asbestos 10 being placed against the sheets of iron 9 11 18 a lens placed in an
opening in the front wall of the box or casing, which may be arranged to slide
in grooves so as to be capable of removal; arranged above and below the lens are
projections 12 formed with grooves 12* for holding the coloured glasses used for
obtaining various effects If necessary the box oi casing 7 may be pivotally
suspended as shown in Fig 3
As will be understood, this invention may be applied to various kinds of are
lamps in addition to that shown in the diawings, which is given merely as an
illustration of the application of the invention to one form of lamp and lantern
For example, an ordinary alternate curient are lamp with globe may be rendered
practically silent by closing the au passages between the inside of the globe and
the external air, and by causing the globe to rest on a pad or cushion of asbestos,
or other suitable material, instead of as usual, directly on the metal support and
by arranging the weather protector or upper case so as to rest on the top of the
globe in a similar way, with an intervening air-excluding and anti-vibration
cushion or separator.

page_text: Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, we declare that what
we claim 18
1 In alternate current aic lamps or lanterns, preventing the transmission of
sound from the aic through air, by completely closing it in or restricting and
lengthening or muffling the air passages and checking or damping the sound
vibrations in the parts of the lamp or lantern by supporting, covering or lining
those parts thereof which are subject to or capable of taking up and transmitting
the sound vibrations with antivibiation substances, substantially as described
2. Alternate current arc lamps o lanterns constructed and arranged sub-
stantially as described with reference to and shewn in the accompanying
drawings
For the Applicant,
W
LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C, Chartered Patent Agent.
W LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C, Chartered Patent Agent.