Year: 1887

page_text: Date of Application, 15th Apr., 1887
Complete Left, 14th Jan., 1888
Complete Accepted, 24th Feb., 1888
We, HENRY WILLOCK RAVENSHAW, of Bull Green Works, Halifax, Yorkshire ;
WALTER THOMAS GOOLDEN, and ALEXANDER PELHAM TROTTER, both of 2 Victoria
Mansions, Westminster, in the County of Middlesex, Electrical Engineers, do hereby
declare the nature of this invention to be as follows:-
This invention relates to improvements in dynamo electric machines having
armatures of the drum type and has for its object the construction of such machines
so as to afford the greatest amount of bearing surface for the shaft or spindle carrying
the armature while at the same time allowing of a considerable reduction being made
in the length of the said shaft.
This is effected by building up the armature upon a hollow bush, or hub, having a
cylindrical opening of a sufficient diameter, for a certain portion of its length, to
allow of the shaft, together with its bearing, passing into the opening, while for the
remainder of its length the opening is of a reduced diameter sufficient only to allow
of the shaft passing through it.
"
The hollow bush, or hub, is firmly keyed upon the shaft, and the usual "spiders
and iron cores are secured thereon. The winding is carried longitudinally along the
surface of the armature, and suitable connections are made with the sections of the
commutator, which may be placed at either end of the armature.
To prevent the turnings of the winding where they pass diametrically across the
end of the armature touching the bearing that projects into that end of the armature
the hollow bush, or hub, may he prolonged for such a distance, in the form of a hollow
cylinder, as to form a fence or guard to the bearing, or a thin cylinder of any suitable
material may be secured to the hollow bush, or hub, in such a manner as will ensure
its projecting over the bearing for the desired distance. Or a number of thịn bars,

page_text: Or strips, either straight or turned up at their outer ends, and curved to the contour of
the hollow bush, or hub, may be employed in place of the hollow cylinder. The
turnings, of the winding, pass round the outside of the thin cylinder, or bars, which,
if of metal, would be suitably insulated, and are thus prevented from coming in
contact with the bearing. The thin cylinder may be provided with a cap, or flange
piece, at its outer end to retain the wires in place.
The armature may rotate between the pole pieces of any suitably formed field
magnets, though it is preferred that the field magnets should be so yoked together as
to allow of the yoke piece being utilised to form part of the bearing for the shaft.
Dated this 15th day of April 1887.
F. SEATON SNOWDON,
Agent for the Applicants.

page_text: COMPLETE SPECIFICATION.
Improvements in Dynamo Electric Machines.
We, HENRY WILLOCK RAVENSHAW, of Bull Green Works, Halifax, Yorkshire;
WALTER THOMAS GOOLDEN, and ALEXANDER PELHAM TROTTER, both of 2 Victoria
Mansions, Westminster, in the County of Middlesex, Electrical Engineers, do hereby
declare the nature of this invention and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:
This invention relates to improvements in dynamo electric machines having
armatures of the drum type and has for its object the construction of such machines
so as to afford the greatest amount of bearing surface for the shaft or spindle carrying
the armature while at the same time allowing of a considerable reduction being made
in the length of the said shaft.
a
This is effected by building up the armature upon a hollow bush, or hub, having
cylindrical opening of a sufficient diameter, for a certain portion of its length, to
allow of the shaft, together with its bearing, passing into the opening, while for the
remainder of its length the opening is of a reduced diameter sufficient only to allow
of the shaft passing through it.
The hollow bush, or hub, is firmly keyed, or otherwise secured, upon the shaft and
the usual "spiders" and iron cores are secured thereon. The winding is effected in
any desired manner, and suitable connections are made with the sections of the
commutator, which may be placed at either end of the armature.
To prevent the turnings of the winding where they pass diametrically across the
end of the armature touching the bearing that projects into the armature, when the
turnings occur at that end of the armature, the hollow bush, or hub, may be prolonged
for such a distance in the form of a hollow cylinder as to form a fence, or guard, to
the bearing, or a thin cylinder of any suitable material may be secured to the hollow
bush, or hub, in such a manner as will ensure its projecting over the bearing for the
desired distance. Or a number of thin bars, or strips, either straight, or turned up
at their outer ends, and curved to the contour of the hollow bush, or hub, in which
they are suitably secured, may be employed in place of the hollow cylinder.
The turnings, of the winding, pass round the outside of the thin cylinder, or bars,
which, if of metal, would be suitably insulated, and are thus prevented from coming
in contact with the bearing. The thin cylinder may be provided with a cap, or
flange, piece at its outer end to retain the wires in place and prevent their slipping
endwise off the cylinder.
The armature may rotate between the pole pieces of any suitably formed field
magnets which may be so yoked together as to allow of the yoke piece being utilised
to form part of the bearing for the shaft if desired.
The hereinbefore described method of construction is more particularly applicable
in the case of dynamo electric generators whose motion is derived direct from a high
speed engine having its shaft coupled direct to the shaft of the armature, or whose

page_text: shaft may be prolonged so as to allow of the armature being mounted thereon. In
the latter case and when using a Brotherhood, Willans, or other similar type' of high
be
speed engine, the stuffing box gland, through which the engine shaft passes, may
prolonged so as to form the armature bearing, the field magnets being supported from
the engine bed plate in any suitable manner.
Having thus indicated the nature of our invention and shown in what manner the
same is to be carried into effect we will now proceed to more particularly describe the
same by reference to the accompanying sheet of drawings.
Figure 1 is an elevation, partly sectional, of an armature constructed in accordance
with this invention. Fig. 2 showing the method employed for, passing the turnings
of the wires across the end of the amature into which the bearing projects.
The shaft, A, runs in the long bearing B, which may either be carried by the
standard C, mounted on the engine bed plate D as shown, or may form part of the
engine bearing as hereinbefore described. The hollow bush, or hub, H, carries
the usual spiders, on which the core is mounted, and is firmly keyed on to the shaft at
any suitable point. The hub is prolonged at H₁ so as to form a fence, or guard, to the
bearing B which projects into this part of the hub.
The shaft A may be carried through the armature and have the commutator
mounted on its outer end A¹, or the commutator may be mounted on the hollow bush,
or cylinder, H¹, the brush holders being then supported by a bracket attached to the
standard C.
The bed plate D may be continued under the armature and have the field magnets,
of any suitable form, bolted onto it, or the field magnets may be so constructed
as to allow of their being bolted onto, or otherwise carried by, the end of the bed
plate D.
The turnings of the wires t, t, are, when the commutator is mounted at A' (Fig. 1)
carried round the hollow bush, or cylinder, H¹ and may, as shown at Fig. 2, he
retained in place by pins, or projections, i, i, constructed in accordance with our
previous application for Letters Patent No. 5303, dated April 12th 1887.
It will be understood that when the commutator is mounted on the hollow bush, or
cylinder, H¹, the turnings of the wires will simply pass across the outer face of the
armature, which will then terminate as, approximately, indicated by the dotted
line a a of Fig. 1.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed we declare that what
we claim is :
First. The method of constructing the armature of a dynamo electric machine so
as to allow of the use of a single bearing for its shaft to run in, substantially as
hereinbefore described and illustrated by Figs. 1 and 2 of the accompanying
drawings.
Second. The alternative method of constructing the armature of a dynamo electric
machine so as to allow of the use of a single bearing for its shaft to run in by
mounting the commutator on the hollow bush, or cylinder, H².
Dated this 14th day of January 1888.
F. SEATON SNOWDON,
Agent for the Applicants.