Improvements in Dynamo Electric Machines and Electric Motors.
Year: 1889

page_text: Date of Application, 12th Apr., 1889
Complete Specification Left, 2nd Sept., 1889-Accepted, 5th Oct., 1889
PROVISIONAL SPECIFICATION.
Improvements in Dynamo Electric Machines and Electric Motors.
I HERBERT NAPIER PRENTICE of 185 Princes Street Ipswich in the County of
Suffolk Electrician do hereby declare the nature of this Invention to be as follows:-
The object of my Invention is to provide a dynamo machine or motor in which
the armature wires and their connections are completely protected from injury by dirt
moisture or otherwise.
According to my Invention I completely cover encase or box in the armature
wires and their connections preferably in the following manner-In the armature
ring at the commutator end I form an annular groove or recess for receiving one end
of a tubular casing which extends forward to beyond the connections of the armature
wires with the commutator strips.
The other end. of this tubular casing is received in a recess or groove in a lisc of
insulating material mounted on the commutator forward of the attachment of the
wires to the strips. At the other end of the armature ring I form an annular groove
or recess in which is received the edge of a cap piece which extends over the
armature wire at that end and is provided with a central opening surrounding and
tightly fitting the shaft.
The main body of the armature I cover with felt or like material and over this I
place bands or wind wires.
All the joints are coeuraly and tightly mado en no to be dirt and water proof
Dril 1889.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in Dynamo Electric Machines and Electric Motors.
I HERBERT NAPIER PRENTICE of 185, Princes Street, Ipswich in the County of
Suffolk 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 provide a dynamo machine or motor in which the
armature wires and their connections are completely protected from injury by dirt
moisture or otherwise. According to my Invention I completely cover encase or box
in the armature wires and their connections preferably in the following manner which
I will explain with reference to the accompanying drawing which shews in Figure 1
a longitudinal section and in Figure 2 an external view of so much of a dynamo
machine as is necessary to illustrate my Invention. In the armature ring at the end
marked A at the commutator end I form an annular groove or recess a for receiving
one end of a tubular casing B which extends forward to beyond the connections of
the armature wires with the commutator strips at c. The other end of this tubular
casing B is received in a recess or groove in a disc of insulating material D mounted
on the commutator forward of the attachment of the wires to the strips. In the
armature ring at the end marked E I form an annular groove or recess e in which is
received the edge of a cap piece G which extends over the armature wires at that end
and is provided with a central opening surrounding and tightly fitting the shaft H
at i. The main body J of the armature I cover with felt or like material as at k and
over this I place bands or wind wires as shewn at I so as to encase or box in and
protect the armature wires, or the said encasing or boxing in of the said wires instead
of extending over the whole body of the armature may be confined to the recesses in

page_text: which the wires are situated. This may be done in such a way as to give a flush
periphery to the armature by forming undercut or V notches in the sides of the tops
of the teeth as shewn in Figure 3 and slipping thereinto strips a of insulating
material similarly formed at their sides or I may apply the insulating material in a
plastic form or in the form of a paste and allow it to harden. All the joints are
securely and tightly made so as to protect the wires from dirt moisture and the like.
Having now particularly described and ascertained the nature of my said Inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1st. A Dynamo electric machine or electric motor with the armature wires and their
connections completely covered encased or boxed in substantially as hereinbefore
described.
2nd. In combination with the armature, armature wires, and their connections, in
dynamo electric machines and electric motors the arrangement and combination of
the casing B cap piece G and an envelope for the main body of the armature sub-
stantially as herein before described and illustrated in the accompanying drawings.
3rd. In combination with the armature armature wires and their connections in
dynamo electric machines and electric motors the arrangement and combination of the
casing B and cap piece G substantially as hereinbefore described and shewn in the
accompanying drawings.
4th. The means for encasing or boxing in the armature wires substantially as
herein before described and illustrated in the several Figures of the accompanying
Drawings.
Dated this 2nd day of September 1889
H. NAPIER PRENTICE.