Year: 1887

page_text: Date of Application, 23rd Aug., 1887
Complete Left, 18th May, 1888
Complete Accepted, 22nd June, 1888
I, EDWARD FREDERICK HERMANN HEINRICK LAUCKERT of Charlton in the County
of Kent, Electrical Engineer, do hereby declare the nature of this invention to be as
follows:-
It has been found advantageous to substitute for the ordinary wire conductors on
the armatures of dynamo machines bar conductors or conductors of comparatively large
size of a rectangular sectional form.
But with such conductors when made of large dimensions the disadvantage arises that
Foucault currents are set up in them whereby they become heated to an injurious
degree.
According to my invention I remedy this defect in the following manner.
Instead of employing a solid bar conductor, I twist together a number of wires to
form a strand which I then subject to powerful compression so as to press the wires
closely together and to cause the strand to assume an oblong or approximately
rectangular sectional form similar to the solid bar conductor.
For this purpose according to one arrangement the wire strand is made on a cable
machine in the usual way and is afterwards drawn through a die having the required
configuration, or according to another arrangement the wire strand is hammered into
shape by means of a steam hammer and dies or pressed into shape by hydraulic power
or otherwise.
The stranded bar thus produced is then insulated for use in the same way as the
ordinary solid bar.
Dated this 23rd day of August 1887.
ABEL & IMRAY,
Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in Dynamo-electric and Electro Dynamic Machines.
I, EDWARD FREDERICK HERMANN HEINRICK LAUCKERT, of Charlton, in the County
of Kent, 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
It has been found advantageous to substitute for the ordinary wire conductors on the
armatures of dynamo machines, bar conductors, or conductors of comparatively large
size of a rectangular sectional form. But with such conductors when made of large
dimensions the disadvantage arises that Foucault currents are set up in them whereby
they become heated to an injurious degree.
According to my invention I remedy this defect in the following manner.
Instead of employing a solid bar conductor, I twist together a number of wires to
form a strand which I then subject to powerful compression so as to press the wires
closely together and to cause the strand to assume an oblong or approximately
rectangular sectional form similar to the solid bar conductor.
For this purpose, according to one arrangement the wire strand is made on a cable
machine in the usual way, and is afterwards drawn through a die having the required
configuration, or according to another arrangement the wire strand is hammered into
shape by means of a steam hammer and dies or pressed into shape by hydraulic power
or otherwise.
The stranded bar thus produced is then insulated for use in the same way as the
ordinary solid bar.
Fig. 1 of the accompanying drawings is a magnified view shewing the transverse
section of a conducting bar of rectangular form made up of a number of wires twisted
into a strand, and then compressed or hammered as above described.
Fig. 2 is a side view, Fig. 3 an end view, and Fig. 4 a plan shewing how connection
may be made at the end of the bar without materially affecting conductivity at the
junction, the end of the bar being for this purpose subjected to such increased pressure
as reduces its width sufficiently to admit of room for the connecting fork which embraces
it not exceeding the general width of the bar.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. A bar conductor for the armatures of electric machines consisting of a twisted
strand of wire compressed to a rectangular section, substantially as herein described.
2. The herein described method of making bar conductors for the armatures of
electric machines by first twisting wires together into a strand and then subjecting
the strand to compression or hammering causing it to assume a rectangular transverse
section.
1
1000