Dynamo Electric Machines.
Year: 1886

page_text: Dynamo Electric Machines.
I, JOHN ROPER, of Trafalger Street, Bradford in the County of York Electrician
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:-
This invention consists in a metallic cap or cover fixed over the end of the
revolving armature of a dynamo electric machine whereby dust and metallic
particles from the commutator are prevented from entering the core of the arma-
ture and thereby interfering with its insulation or efficiency, and at the same
time the connecting wires between the commutator and the various coils of the
armature are covered over and protected from disarrangement or injury.
My invention will be more clearly understood by reference to the drawings
froming part of this specification in which Figure 1 represents a front elevation
partly in section of the cap or cover hereinafter described, Figure 2. represents a
sectional elevation of the cap or cover in the line of the axis of the armature,
Figure 3 represents an elevation of the inner side of the cover or cap and Figure.4
represents so much of the end of the armature with the cap placed thereon as is
required to demonstrate the manner in which the cap is applied.
Similar letters of reference indicate similar parts in each of the drawings.
The metallic cap or cover represented at A. fits upon the end of the armature B
which is nearest to the commutator C, and is carried on the shaft D by means of
arms which are either cast integrally with the boss and the cap or cover, or they
are fixed thereto by means of screws or rivets, and a hole G is formed in the boss
to receive the shaft D.
The cap or cover A slightly overlaps the ends of the coils of wire of the arma-
ture B, thereby forming a dust-proof joint, and the outside of the cap nearest to
the commutator is closed by means of a disc E of slate or other suitable non
conducting material, which disc is secured to the lugs F formed or fixed inside the
periphery of the cap or cover A This disc of slate or other non conducting
material is fixed to the lugs F by means of screws, by removing which the disc
can be taken out, in order to allow access to the interior of the armature, and to
the connecting wires from the commutator to the armature.

page_text: The cover with the slate disc, when secured in its proper position, prevents dust
or the fine metallic particles arising from the commutator from being carried into
the armature, where they would interfere with the insulation and the effective
working of the machine.
The cap with its closing disc hereinbefore described also forms a shield for the
protection of the wires which connect the various coils of which the armature is
principally composed, and the metallic arms upon which the cap or cover is
mounted form a support or frame for the armature, but have no electrical connec-
tion therewith.
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed, I declare that what
I claim is
In connection with a dynamo-electric machine a cap or cover placed upon the
end of the armature, the arms of which cap or cover are insulated from the wires
of the commutator and of the armature, and the outer opening of which cap is
closed by means of a disc of slate or other non conducting material, all operating
for the purpose, and constructed substantially in the manner described, and repre-
sented in the accompanying drawings.
1
1
1000