Improvements in Induction Electrical Machines.
Year: 1894

page_text: Date of Application, 12th Feb., 1894-Accepted, 17th Mar., 1894
COMPLETE SPECIFICATION.
Improvements in Induction Electrical Machines.
I, FREDERICK TUDSBURY of Edwinstowe, Newark, in the County of
Nottingham, Electrician, do hereby declare the nature of my said invention and in
what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement:-
The object of my invention is to increase the power and efficiency of induction
electrical machines as at present made.
My improvements are more particularly applicable to machines of the
"Wimshurst" type which is a statical induction electrical machine of simple
construction capable of producing a continuous discharge between its terminal
electrodes.
This machine as at present constructed consists of two cylinders, one within the
other, or two discs face to face, mounted upon a fixed horizontal spindle and rotated
in opposite directions at a slight distance apart.
The cylinders or discs thus employed are constructed of ebonite, glass or other
suitable material and are provided on their outer or friction surfaces with metallic
inductors, or carriers disposed at equal distances apart. These metallic inductors
or carriers are attached to the cylinders or discs by cement and the whole of their
superficies is exposed to the act.on of the neutralizing brushes and collectors.
It is with regard to this particular portion of the apparatus that my improve-
ments are directed.
In lieu of the method just described for attaching the metallic inductors or
carriers I enclose them between two sheets or discs of the material of which the
cylinders or discs are made or by embedding the metallic inductors or carriers and
afterwards covering or closing them over.
Where the inductors or carriers are placed between two sheets or discs I cement
them together with a non-conduct ng material so that each inductor or carrier is
insulated from its neighbour or when ebonite is employed in the construction of
the cyl nders or discs the inductors or carriers may be embedded and covered
before vulcanizing.
I provide on each inductor or carrier a metallic stud or connecting bit which
pierces to the outer or friction surface of the cylinder or disc as the case may be.
As a further improvement I place the inductors or carriers so that the studs or
connecting bits are exposed in two or more rows or lines so that two or more
neutralizing brushes or one wide brush may be employed on each arm.
Thus where two neutralizing brushes are employed on each arm, every alternate
inductor or carrier would be placed with the studs or connecting bits at opposite
ends, and where three neutralizing brushes are employed on each arm an
intermediate inductor or carrier would be used with the stud or connecting bit
placed in the centre. By which means two or three lines of contact would be
provided and the electricity generated would pass from the inductors or carriers
through the medium of these studs or connecting bits and in this way a more
powerful current set up.
I do not confine myself to the number or arrangement of the metallic inductors
or carriers with their studs or connecting bits nor to the number of neutralizing
brushes employed.
The nature of my invention will be better understood on reference to the
accompanying sheet of drawings in which,
Fig. 1, represents the plan of a portion of the outer or friction surface of a
cylinder shewing the arrangement and disposition of the inductors or carriers with
their studs or connecting bits where two neutralizing brushes are employed and,

page_text: Fig. 2, represents a similar plan where three neutralizing brushes are employed.
Figs. 3 and 4, represent similar arrangements as applied to a disc.
The same letters refer to similar parts throughout the several views.
a, is the outer or friction surface of the cylinder or disc.
b, b, are the metallic inductors or carriers.
c, c, are the metallic studs or connecting bits on the same.
Having now particularly described and ascertained the nature of my inven-
tion and in what manner the same is to be performed I declare that what I
claim is,
1. In an induction electrical machine covering embedding or enclosing the
metallic inductors or carriers in or between the material of which the cylinders or
discs are constructed and providing them with studs or connecting pieces to pierce
the outer or friction surface of the said cylinders or discs in the manner and for
the purposes substantially as herein described and illustrated.
2. In an induction electrical machine placing and arranging the metallic
inductors or carriers covered, embedded or enclosed as described in Claim 1, in
such a manner that the studs or connecting pieces may be brought in line of
contact with one wide or with two, three, or more narrow neutralizing brushes in
the manner and for the purposes substantially as herein described and illustrated.
Dated this 6th day of February 1894.
R. HEBER RADFORD,
Agent for the Applicant.