Improvements in Electric Arc Lamps for Stage and the like purpose
Year: 1899

page_text: Date of Application, 27th Jan., 1899
Complete Specification Left, 27th Oct., 1899-Accepted, 2nd Dec., 1899
--PROVISIONAL SPECIFICATION.
Improvements in Electric Arc Lamps for Stage and the like purpose3.
I, JOHN WEBSTER, of 15, Bayswater Crescent, Roundhay Road, Leeds, in the
County of York, Electrical Engineer, do hereby declare the nature of this invention
to be as follows;-
My stage arc lamp consists of two arms forming the carbon holders carried in
suitable brackets carried upon a vertical pillar, the brackets being loose on the
spindle and kept in position by spiral springs between the central adjusting fixed
bracket and the said loose brackets. The central bracket carries a wheel and
adjusting screw, the said adjusting screw at its end being secured by nuts or
washers in a fork in which it revolves, and the fork carrying the cranked arms of
the two holders, preferably on one centre or pivot.
The pillar is carried upon a tray with adjustable bearings consisting of regulat-
ing screws, so as to minutely adjust the position of the pillar, either forwards,
sideways, or in any other direction required for focussing.
The adjusting screw of the central bracket is provided with automatic stops,
so that the carbon holders or arms cannot be closed or opened further than required.
For securing the lamp within the box a screw is provided in the tray bottom to
abut and tighten it against the tray when in position, and so prevent accidental
breakage.
The reflector is fixed upon one of the terminals of the arms behind the carbon,
and is slotted over the other, so that a constant equal light is diffused upon the
stage on an alternating current circuit.
JOHN E. WALSH,
Royal Exchange Chambers, Boar Lane, Leeds,
Patent Agent for the Applicant.
Improvements in Electric Arc Lamps for Stage and the like purposes.
I, JOHN WEBSTER, of 15, Bayswater Crescent, Roundhay Road, Leeds, in the
County of York, 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:--
My invention relates to are lamps for stage and like purposes, the object being
mainly to increase the light power of such lamps and to provide an improved
means of adjusting the carbon holders, so preventing the burning out of the carbon
holders.

page_text: DESCRIPTION OF DRAWINGS.
Fig. 1 is a side elevation of my improved lamp in position, the box or casing
being shown in section.
Fig. 2 is a plan of the lamp withdrawn from the box.
In constructing my improved stage are lamp I employ two arms A.A forming
or carrying the carbon holders, these arms being carried by brackets B B mounted
loosely on a vertical pillar C. The said brackets B B are retained in position by
spiral springs DD, which abut on the central adjusting bracket. E, which is
clamped at a suitable height by a thumbscrew F. The said bracket E carries an
adjusting screw G with wheel H, the screw G working in a screwed bush J on the
bracket so as to operate the fork K, which carries the cranked ends L L of the
arms A, A, preferably on one centre or pivot M. The said screw G is also provided
at each end with automatic stops to limit the opening and closing of the arms A A.
The pillar C is carried on a tray N, which slides between suitable guides P, P,
on the bottom of the box R, and carries a thumbscrew S. for focussing the lamp
and securing it' in position within the box to prevent accidental breakage.
The arms or carbon holders A, A, have preferably detachable ends secured by
bolts T and pivot T', and carrying pivotted carbon grippers YY operated by
screws ZZ. A reflector U is fixed to the upper arm behind the carbon, and is
slotted over the lower arm, so that a constant equal light is diffused upon the stage
on an alternating current circuit.
V is the lens slide with hinged cover W, and X is the slide for the coloured.
mediums.
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. In an electric arc lamp for stage and like purposes, the employment of carbon
holders carried by the adjustable cranked arms AL, AL, such arms being carried
on a pillar C by loose spring brackets B B, and being adjusted by a screw G
carried by an intermediate fixed bracket E, substantially as shown and described.
2. In an electric arc lamp having cranked carbon-holding arms with screw
adjustment, the employment of an adjusting screw with automatic stops at each.
end to limit the opening and closing of such arms and so prevent burning out the
carbon holders, substantially as shown and described.
3. In an electric arc lamp having cranked carbon-holding arms, the employ-
ment of a reflector fixed to the upper arm and slotted over the lower arm, sub-
stantially as shown and described.
4. In an electric arc lamp having carbon holders carried on a vertical pillar,
the means for focussing, adjusting, and fixing the lamp within the box or casing,.
substantially as shown and described.
Dated this 26th day of Octalion 1900.
JOHN E. WALSH,
Royal Exchange Chambers, Boar Lane, Leeds,
Patent Agent for the Applicant.