Year: 1887

page_text: Date of Application, 12th July, 1887.
Specification Accepted, 23rd Aug., 1887.
[Communicated from abroad by GEORGE WESTINGHOUSE, junior, of Pittsburg,
County of Alleghany, State of Pennsylvania, United States of America,
Engineer.]
1, WILLIAM PHILLIPS THOMPSON, F.C.S. M.I.M.E. of the Agency for Foreign
Patent Solicitors 6, Lord Street Liverpool and 6, Bank Street, Manchester both in
the County of Lancaster, and 323 High Holborn in the County of Middlesex, Civil
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 :—
The invention relates to the class of apparatus employed for transforming electric
currents of any given potential into currents of a different potential; such devices are
usually termed induction coils or electric converters.
The object of the present invention is to provide an electric converter which may be
conveniently employed in transforming the alternating currents of high potential
conveyed along the streets of a city or town by primary conductors, into secondary or
induced currents at such points as may be found desirable. To this end the invention
consists generally in constructing the converters in the form of cylinders of such size
as to be conveniently placed inside the lamp-posts placed along the line of primary
conductors. The cores of the converters are preferably built up of thin sheets or
plates of soft iron circular in form, which are stamped with two openings for receiving
the coils. The metal is cut through for each opening, leaving a tongue between the
same, which is inserted within the primary and secondary coils. The metal closes
about these coils thus surrounding them with thin laminae of soft-iron.
The invention further contemplates the employment of a continuous back-piece for
the laminated core. This hack piece may consist of a tube or cylinder of soft-iron
fitting over the core, or when the converter is placed within an iron lamp-post the
metal of the post may serve this purpose if so desired.

page_text: In the accompanying drawing, Figure 1 is a transverse section and Figure 2 a side
view partly in section of a converter embodying the features of the invention.
Figure 3 illustrates the application to a lamp-post.
Referring to the figures, A represents the core of a converter and P and S
respectively represent the primary and secondary coils. These coils are preferably
separately wound and the core is applied afterward. The core consists of a series
of discs of soft-iron, a, a, each having openings 61, 62 for receiving the coils. The
openings are cut open as shown at c¹ and c². The edges e¹ and e³ are bent back, when
the core is being built up, and the central tongues a' are inserted, alternate plates
being preferably applied from opposite sides.
The plates a, a are preferably covered with some non-magnetic substance, such for
instance as paper, upon one side. By placing the adjacent plates with their bare
surfaces in contact with each other and then placing the covered surface of the
succeeding plate against the corresponding surface of one of the first plates; and
continuing the same arrangement a very serviceable construction is secured.
When the core has been properly built up, the entire converter is placed in a solid
tube F of soft-iron, properly fitted thereto. The entire converter may then be
inserted within the post which is to contain it, and the primary coil has its circuit-
connections completed with the conductors designed to supply the currents thereto.
Conductors are led from the secondary coils in any desired manner. It may be
desired to place one or more incandescent electric lamps upon the post and supply
them with currents from the converter in a manner well understood.
The tube F may be dispensed with if desired; and in some instances the iron of
the posts will serve in lieu thereof. It will be understood, however, that the converter
is of use in other places than in the lamp-posts.
Having now particularly described and ascertained the nature of the said invention
and in what manner the same is to be performed, as communicated to me by my
foreign correspondent, I declare that what I claim is :-
1. The combination of primary and secondary conductors, a core of soft-iron plates
circular in form, each plate having two openings for receiving the coils, the metal
about each opening being cut apart, substantially as described, and a cylindrical
enclosing case for the same.
2. An electric converter consisting of primary and secondary coils, a core of
circular soft-iron plates or discs, and an enclosing tube of soft-iron.
3. An electric converter consisting of primary and secondary coils, a core of soft
iron cylindrical in form and composed of thin plates, in combination with a lamp-post
of iron having a cylindrical opening containing the same and in magnetic connection
therewith.
4. An electric converter consisting of primary and secondary coils, and a core
composed of soft-iron plates, and a solid back piece common to all the plates.
5. An electric converter consisting of primary and secondary coils, and a core
consisting of laminae of soft-iron magnetically separated through the greater portion
of their surfaces and magnetically united at their edges.
6. An electric converter consisting of the combination of primary and secondary
conductors, and a core of soft-iron plates, and an enclosing case of soft-iron.
7. The combinaton with the primary and secondary coils of a converter and a core
of soft-iron to which they are applied, of a soft-iron enclosing case for the same.