Year: 1887

page_text: Date of Application, 19th Sept., 1887
Complete Specification Left, 19th June, 1888
Complete Specification Accepted, 19th Nov., 1888
We, WALTER THOMAS GOOLDEN and LLEWELYN BIROHALL ATKINSON, of 2 Victoria
Mansions, Westminster, in the County of Middlesex, and Bull Green Works, Halifax,
Yorkshire, Electrical Engineers, do hereby declare the nature of this invention to be
as follows:
This invention relates to improvements in dynamo-electric generators and motors,
and has for its object the providing of means whereby the whole of the moving parts
of such machines, together with the brushes and their holders, are protected against
the effects of the weather, and which means also allow of machines so constructed
being safely worked, and efficiently ventilated, while in the presence of explosive gases,
such as obtain in coal mines, without the risks attending upon the use of such machines
as heretofore constructed, and when working under the like conditions.
The invention consists in applying to dynamo-electric-generators, or motors, a casing
or covering, preferably of non-magnetic metal, and which may conveniently be
made of wire gauze. The casing starting at the pole pieces, or magnet bars, is con-
tinuous with the pedestals carrying the shaft, or the casing may be so constructed as
to form the carriers of the bushes, in which the shaft revolves.
The casing may be made in parts, or be provided with openings to allow of ready
access to the interior parts for examination, while in order to admit of the working of
the brushes and commutator being inspected windows, of glass, horn, or other suitable
substance are provided.
The spaces between the pole pieces, on the periphery of the armature, are also
enclosed by metallic gauze, or other suitable covering, so that the whole armature,
commutator and brushes, shall be completely encased as a protection against atmospheric
changes, or to exclude explosive gases according to the situation in which the machine
is employed.
When specially designed for use with machines intended to be used in coal mines,
or other dangerous places, the covering may consist of two or more casings arranged
as outer, inner, and, if necessary intermediate coverings, provision being made to
maintain a circulation of air, or other cooling medium, between the outer and inner

page_text: casings, by which the heat, radiated from the armature and other working parts, would
be conveyed away, or ventilation may be effected by the use of air passages, or
channels, so arranged, however, and of such a length and position, as not to vitiate
the object in view, videlicet, the efficient ventilation of the working parts of a
dynamo-electric generator, or motor, in such a manner as will allow of the ingress of
air to the interior parts while not allowing of the egress of flame therefrom.
To prevent any flame that might arise from the brushes doing injury to the internal
parts of the machine, when working in a gas impregnated atmosphere, the covered
chamber in which the armature revolves may be provided with a pipe leading to a
vessel charged with carbonic acid gas, or other non-supporter of combustion, a stop
cock serving to control the supply of the same to the chamber.
Or the air caused to pass between the casings, for the purpose of ventilation, may be
impregnated with some such non-supporter of combustion.
Though described as being applied to machines where it is desired to exclude the
atmosphere, or gases, it will be understood that the invention is equally applicable to
motors working tramcars, or in other positions where dust may be encountered.
Dated this 19th day of September 1887.
F. SEATON SNOWDON,
Agent for the Applicants.

page_text: COMPLETE SPECIFICATION.
Improvements in Dynamo-electric Generators and Motors.
We, WALTER THOMAS GOOLDEN and LLEWELYN BIRCHALL ATKINSON, of 2, Victoria
Mansions, Westminster, in the County of Middlesex, and Bull Green Works, Halifax,
Yorkshire, Electrical Engineers, 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 relates to improvements in dynamo-electric generators and motors,
and has for its object the providing of means whereby the whole of the moving parts
of such machines, together with the brushes and their holders, are protected against
the effects of the weather, and which means also allow of machines so constructed
being safely worked, and efficiently ventilated, while in the presence of explosive
gases, such as obtain in coal mines, without the risks attending upon the use of such
machines as heretofore constructed, and when working under the like conditions.
The invention consists in applying to dynamo-electric generators, or motors, a
casing, or covering, preferably of non-magnetic metal, and which may conveniently be
made of wire gauze.
The casing, starting at the pole pieces or magnet bars, is continuous with the pedestals
carrying the shaft, or the casing may be so constructed as to form the carriers of the
brushes, in which the shaft revolves.
The casing may be made in parts, or be provided with openings to allow of ready
access to the interior parts for examination, while in order to admit of the working of
the brushes and commutators being inspected, windows of glass, horn, or other
suitable substance are provided. The spaces between the pole pieces, on the periphery
of the armature, are also enclosed by metallic gauze, or other suitable covering, so
that the whole armature, commutator and brushes, shall be completely encased as a
protection against atmospheric changes, or to exclude explosive gases according to the
situation in which the machine is employed.
When specially designed for use with machines intended to be used in coal mines,
or other dangerous places, the covering may consist of two or more casings arranged
as outer, uner, and, if necessary, intermediate coverings, provision being made to
maintain a circulation of air, or other cooling medium, between the outer and inner
casings by which the heat, radiated from the armature and other working parts,
would be conveyed away, or ventilation may be effected by the use of air passages,
or channels, so arranged, however, and of such a length and position as not to
vitiate the object in view, videlicet, the efficient ventilation of the working parts of a
dynamo-electric generator, or motor, in such a manner as will allow of the ingress of
air to the interior parts while not allowing of the egress of flame therefrom.

page_text: To prevent any flame that might arise from the brushes doing injury to the internal
parts of the machine when working in a gas impregnated atmosphere the covered
chamber in which the armature revolves may be provided with a pipe leading to a
vessel charged with carbonic acid gas, or other non-supporter of combustion, a stop
cock serving to control the supply to the chamber. Or the air caused to pass between
the casings for the purpose of ventilation, may be impregnated with some such non-
supporter of combustion.
Though described as being applied to machines where it is desired to exclude the
atmosphere, or gases, it will be understood that the herein before describal invention is
also equally applicable to motors working tramcars, or in other positions where dust,
or dampness, may be encountered.
Having thus set forth the nature of our invention we will now proceed to more
particularly describe how the same is carried into effect by reference to the accom-
panying drawings.
Figure 1 shows, an arrangement, partly in elevation and partly in section, in which
the casing is so constructed as to include the bearings in which the shaft, or spindle,
rotates, while Figure 2 shows an arrangement, also partly in section and partly in
elevation, in which the shaft, or spindle, rotates in bearings carried by the ordinary
pedestals of the machine.
In Figure 1 the casing CC is constructed in any desired number of parts, bolted
together so as to ensure the joints being air-tight, and is suitably secured to the top of
the magnet bars M. M. and the pole pieces in which the armature A revolves.
The casing, made of any suitable non-magnetic metal, or alloy, such as gun-metal,
passes between the magnet bars, to each of which it is rigidly, and air-tightly secured,
and thus completely envelopes the armature, while the prolongation at D carrying the
bearing E in which the shaft S rotates prevents the ingress of air to this end of the
armature.
The
Similarly the brushes B, B, and commutator C, are protected from the effects of the
atmosphere, or danger when working in a gas impregnated atmosphere, by the box
liko receptacles G G secured to the prolongation H of the casing C
receptacles G, G, are provided with glass, or other, windows g through which the
working of the brushes B, B, and commutator may be readily seen, while the
prolongation H is continued to H' so as to form a bearing for the end S¹ of the shaft,
or spindle.
Though not shown in connection with any system of ventilation it will be under-
stood that the interior of the case C, C, may be placed in communication, by means
of suitable pipes and stop cocks, with any source from whence air, or, if required, a
non-supporter of combustion, such as carbonic acid gas, may be supplied.
In the arrangement shown in Figure 2 the shaft S, S', is carried by the
pedestals P, P¹, bolted to, or forming part of, the bed or foundation plate in the
ordinary way.
The casing C, C, is attached to the top of the magnet bars M and secured to
the pole pieces as in the case of the arrangement shown in Figure 1, the brushes B
and commutator C being protected by the cylindrical casing G₁ provided with suitable
windows and bolted, or otherwise secured airtight to the deep flanged prolongation H
of the casing C, while provision for ventilating the armature is made as follows. The
prolongation Di terminates, at its outer extremity, at a circular aperture 6, through
which the cylindrical neck c of an inwardly domed, or dished, plate, or casting, J
passes. The dome J is so proportioned and placed with reference to the prolonga-
tion D', to which, or the pedestal P, it is suitably secured, as to allow a passage a
between the two of such dimensions only as will allow the ingress of air to the interior
of the casing C, but will prevent the egress of flame therefrom. It will be under-
stood that to further prevent the egress of flame the adjacent faces of the dome J
and prolongation D₁ may be provided with a number of thin ribs, or vanes, so
disposed and formed as to constitute a number of minute channels lying either
in planes parallel to the axis of rotation of the shatt S, S¹, or more or less oblique
thereto.

page_text: Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is
First. The method of completely surrounding, or encasing, the armature, com-
mutator and brushes of a dynamo-electric generator, or motor, by an airtight non-
magnetic metal, or gauze, casing in the manner substantially as herein before described,
and shown by Figure 1 of the accompanying drawings.
Second. Supplying air, or a non-supporter of combustion, or air impregnated with
a non-supporter of combustion, to the interior of the airtight casing surrounding the
armature, commutator and brushes of a dynamo-electric generator, or motor in the
manner substantially as hereinbefore described with reference to Figure 1 of
the accompanying drawings.
Third. The herein before described method of encasing the armature, commutator and
brushes of a dynamo-electric generator, or motor, in such a way as will allow the free
ingress of air, for ventilation, to such parts, but will prevent the egress of flame
therefrom, in the manner substantially as described with reference to Figure 2 of the
accompanying drawings.