Improvements in Electric Arc Lamps,
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improvements in Electric Arc Lamps,
We, WALLACE JAMES LAMBERT SANDY, of 20, John Street, Adelphi, in the
County of Middlesex, DOUGLAS CLAVELL BATE, of 127, East Dulwich Grove, in
the County of Surrey, and THOMAS GEER, of Ventnor Villa, Goldsmith Road, New
Southgate, in the County of Middlesex, Electrical Engineers, do hereby declare
the nature of this invention to be as follows:-
According to this invention the upper carbon is free to slide in a sleeve placed
centrally above the globe, being supported by a clutch preferably consisting of
two parallel bars connected together by links in which are holes approximately
the sizes of the carbon. The end of one of the parallel bars is connected to the
sleeve whilst the end of the opposite bar when the sleeve descends comes against
the cover of the globe or any suitable stop. When this takes place the clutch is
opened and ceases to grip the carbon which is then free to slide down the sleeve
by its own weight; on the other hand when the sleeve moves upwards the clutch
grips the carbon and raises it.
The motion of the sleeve is controlled in the usual manner by a solenoid or
solenoids.
On the sleeve is a plunger which moves up and down in a dash pot so pre-
venting any abrupt movement.
The dash pot may either be inside the solenoid or above it, in this latter case
the carbon may be of almost any length as a continuation of the sleeve may be
provided consisting of a non-magnetic material and the dash pot may be fixed at
the required height.
In an enclosed arc lamp the cover of the enclosing globe is made with a recess
in the centre, in which is a loose flange of smaller diameter than the recess;
through this flange the upper carbon is free to slide, any want of straightness in
the carbon being compensated for by the movement of the flange within the
recess. The joint between the cover and the globe may be made by fitting the
globe in a concentric groove which may be packed with asbestos or similar sub-
stance.
Dated this 4th day of May 1808
WALLACE JAMES LAMBERT SANDY.
DOUGLAS C. BATE.
THOMAS GEER,

page_text: Improvements in Electric Arc Lamps.
We, WALLACE JAMES LAMBERT SANDY, of 20, John Street, Adelphi, in the
County of Middlesex, DOUGLAS CLAVELL BATE, of 127, East Dulwich Grove, in
the County of Surrey, and THOMAS GEER, of Ventnor Villa, Goldsmith Road, New
Southgate, in the County of Middlesex, Electrical Engineers, 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:-
According to this invention the upper carbon is free to slide in a sleeve placed
centrally above the globe, being supported by a clutch preferably consisting of
two parallel bars connected together by links in which are holes approximately
the sizes of the carbon. The end of one of the parallel bars is connected to the
sleeve whilst the end of the opposite bar when the sleeve descends comes against
the cover of the globe or any suitable stop. When this takes place the clutch is
opened and ceases to grip the carbon which is then free to slide down the sleeve
by its own weight; on the other hand when the sleeve moves upwards the clutch
grips the carbon and raises it.
The motion of the sleeve is controlled in the usual manner by a solenoid or
solenoids.
On the sleeve is a plunger which moves up and down in a dash pot so pre-
venting any abrupt movement.
The dash pot may either be inside the solenoid or above it, in this latter case
the carbon may be of almost any length as a continuation of the sleeve may be
provided consisting of a non-magnetic material and the dash pot may be fixed at
the required height.
In an enclosed are lamp the cover of the enclosing globe is made with a hole
in the centre, in which is a loose flanged tube of smaller diameter than the hole,
through this flanged tube the upper carbon is free to slide, any want of straightness
in the carbon being compensated for by the movement of the flanged tube within
the hole. The joint between the cover and the globe may be made by fitting the
globe in a concentric groove which may be packed with asbestos or similar sub-
stance.
The drawing is a vertical section of a lamp constructed according to this inven-
tion.
a is the solenoid, 6 is its core which is hollow and contains the upper carbon c.
d is a plunger fixed to the core band working loosely in the solenoid a so forming
a dash pot. ele²e are four rods jointed together, e being fixed to the core b
whilst e hangs free. On the descent however of the core the end of e¹ comes
against the plate fx on the top of the lamp cover f which is preferably of slate
causing the rods to release the carbon. is a flanged tube loosely fitting the
hole in the cover f. The top of the globe / fits into a groove f in the eover
and bears against the washer j.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what
we claim is:-
1. The combination of a solenoid, a sleeve forming the core of the solenoid or
a continuation of it a clutch carried by the sleeve, a dash pot in or above the
solenoid and a plunger in the dash pot fixed to the sleeve,
2. A carbon clutch consisting of two vertical rods and two parallel and approxi-

page_text: mately horizontal rods pivotted to them, one of the vertical rods being fixed to
the core of the solenoid, the other hanging free but arrested by a stop- when the
core descends and the two horizontal rods having holes in them through which
the carbon passes.
3. The combination with the cover of the enclosing globe of a hole in it and a
loose flanged tube of smaller diameter than the hole.
4. Electric arc lamps substantially as described and illustrated in the drawing.
Dated this 6th day of February 1899.
DOUGLAS C. BATE.
WALLACE J. L. SANDY.
THOMAS GEER.