Improvements in Dynamo-electric Generators and Motors.
Year: 1887

page_text: This Specification was, upon the 18th day of December 1891, Amended under
Sections 18 to 21 of the Patents, Designs, and Trade Marks Act, 1883.
PROVISIONAL SPECIFICATION.
Improvements in Dynamo-electric Generators and Motors.
We, WALTER THOMAS GOOLDEN, and LLEWELLYN BIRCHALL ATKINSON, both of
2 Victoria Mansions, Westminster, 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 provision of means for enclosing the brushes and commutators
of such machines so as to render them suitable for working in the presence of
inflammable or explosive gases, and under circumstances where it is necessary to
exclude the atmosphere from these parts, the improvements relating more parti-
cularly to those cases where it is not necessary or advisable to enclose the whole
armature.
In the case of a dynamo-electric generator, or motor, either of the open coil, or
close coil, type and having a commutator of few parts or so constructed as to allow of
small wires or connections being used to connect the armature coils to the segments
of the commutator, a hollow shaft may be used through which the wires or connections
pass to the commutator, placed, in this case, outside, or beyond, the bearing or journal.
When so placed the whole commutator may be enclosed, up to the journal, the brushes
and their holders being either placed completely inside the casing, or held partly
protruding in the enclosed brush holders composed of a movable or fixed casing
carrying the brush holders proper.
Should the commutator connections be too large, or for other reasons the above
method of carrying this invention into effect become undesirable then the object may
be attained by the employment of the following means.
The brushes in this case are wholly, or partly, enclosed in a casing, or chamber,
which may form part of the brush holder, and may be either fixed or movable so as to
allow of the adjustment of the brushes. The casing, or chamber, encloses the com-
mutator and has its end nearest the armature so formed as to embrace a packing ring,
analogous to the packing ring of an engine's piston rod, and by this means the

page_text: commutator is completely isolated from the outer atmosphere. The packing material
employed would be an insulating material, asbestos being very suitable for the
purpose.
To avoid the possible short circuiting of the armature coils that might be caused by
the fine copper particles, (due to the wearing of the commutator and brushes)
becoming attached to the packing, a ring of insulating material, or of metal insulated
from it, may be suitably secured to the commutator, the packing bearing on this ring
instead of on the commutator direct.
In this case the packing may be of asbestos, metal gauze, or other material, or
spring rings may be employed for the purpose. The chamber surrounding the com-
inutator may be provided with openings for ventilation, or inspection, the openings
being protected by gauze, glass, mica or other suitable material. The chamber may
be filled with a non-supporter of combustion, such as carbonic acid gas, or it may
be arranged so as to be capable of receiving a supply of such gas should it be
necessary.
It will be understood that in certain cases an absolute air-tight packing of the
commutator within the casing, or chamber, may not be necessary, it being sufficient
to reduce the air space between the commutator, or the ring carried by it, and
the casing, to such a small amount, as will prevent the passage of flame, absolute
contact between the commutator, or its ring, and the casing being avoided.
Dated this 2nd day of December 1887.
F. SEATON SNOWDON,
Agent for the Applicants.

page_text: Improvements in Dynamo-electric Generators and Motors.
We, WALTER THOMAS GOOLDEN, and LLEWELLYN BIRCHALL ATKINSON, both of
2 Victoria Mansions, Westminster, London, S. W., 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 provision of means for onclosing the brushes and com-
mutators of such machines so as to render them suitable for working in the
presence of inflammable, or explosive, gases, and under circumstances where it is
necessary to exclude the atmosphere from these parts, the improvements relating
more particularly to those cases where it is not necessary, or, from the nature of its
construction, advisable to enclose the whole armature.
In the case of a dynamo electric generator, or motor, either of the open coil, or
close coil, type and having a commutator of few parts, or so constructed as to allow
of small wires or connections being used to connect the armature coils to the
segments of the commutator a hollow shaft may be used through which the wires, or
connections, pass to the commutator placed, in this case, outside, or beyond, the
bearing or journal. When so placed the whole commutator may be enclosed, up to
the journal, the brushes and their holders being either placed completely inside the
casing, or held partly protruding in the enclosed brush holders, composed of a movable
or fixed casing carrying the brush holders proper.
This method of carrying our invention into effect is shown by Figures 1 and 2 of
the accompanying drawings, of which Fig. 1 is a side elevation partly in section, and
Fig. 2 an end elevation.
In these figures the ends of the coil wires, proceeding from the armature a,
are carried through the opening into the hollow shaft, passing through the
When
bearing C, and coming out to the commutator collector sections at d.
employing brushes of the forward thrust box type they are fixed into the case e
through insulating pieces i, the whole case being capable of movement round the end
of the bearing bracket C, where it is fixed, or clamped, after being properly adjusted,
by means of the bolts and nuts shown. The end of the case is removable for
inspection or adjustment of the interior parts, a side opening k, being also provided
for the like purpose.
Should it be desired to employ brush holders swinging on pivots, or otherwise, the
case e would be so proportioned as to admit of its carrying the entire brush holders
and brushes, the same being mounted on a separate carrier which may be attached
to the inside of the casing in any suitable manner, as will be well understood.
Should the cominutator connections be too large or for other reasons the above
described method of carrying this our invention into effect become undesirable then
the object may be attained by employing the following means.
The brushes in this case are, as in the hereinbefore described arrangement, partly,

page_text: or wholly, enclosed in a casing, or chamber, which may form part of the brush
holder, and may be either fixed or movable so as to allow of the adjustment of the
brushes.
The casing, or chamber, encloses the commutator and has its end nearest the
armature so formed as to embrace a packing ring, analogous to the packing ring of an
engine's piston rod, and by this means the commutator is completely isolated from
the outer atmosphere. The material employed for the packing ring would be an
insulating material, asbestos being a very suitable material for the purpose, while
further to avoid the possible short circuiting of the armature coils that might be
caused by the fine copper particles (due to the wearing of the commutator and
brushes) becoming attached to the packing, a ring of insulating material, or of metal
insulated from it, may be suitably secured to the commutator, the packing bearing on
this ring instead of on the commutator direct.
In this case the packing may be of asbestos, metal gauze, or other suitable material,
or spring rings may be employed for the purpose. The chamber surrounding the
commutator may be provided with openings for ventilation or inspection, the openings
being protected by gauze, glass, mica, or other suitable material. The chamber may
be fitted with a non-supporter of combustion, such as carbonic acid gas, or it may
be arranged so as to be capable of receiving a supply of such gas should it be
necessary.
9
This method of carrying our invention into effect is shown by Figures 3 and 4 of
the accompanying drawings, of which Fig. 3 is a side elevation, partly in section, and
Fig. 4 and end elevation
In these figures a is the armature whose coils are connected, by the radial coil
connections b, to the segments of the commutator d.
The brushes of the forward thrust box type are carried by insulating pieces i
passing through the chamber, or case, e, which as in the previously described arrange-
ment illustrated by Figs. 1 and 2, is capable of being rocked for the purpose of
altering the position of the brushes on the commutator d. On the commutator dis
placed an insulating ring, which is securely fixed by being carried between two
inclined wedging rings g,g. The end of the case e nearest the armature is constructed
to receive a packing gland h, which on being screwed home presses on the packing
ring and so brings it into contact with, and all round, the insulating collar.
It will be understood that in this method of carrying our invention into effect
brushes of the rocking bar, or other type, may be employed, the chamber, or casing, e,
being proportionately enlarged, and suitably constructed, as was shown with reference
to the first described method.
When designed to cover, or protect, the commutators of dynamo-electric machines
having ring armatures, the insulating collar, (as shown at ƒ Fig. 3) may be carried
direct on the shaft, the wires connecting the coils on the armature with the segments
of the commutator, and which wires, in this type of machine, run parallel with the
shaft for some distance, passing through suitable holes, or slots, in the collar. By this
means the collar may be mounted direct on the shaft instead of on the commutator as
shown in Fig. 3.
It will be understood that in certain cases an absolute air tight packing of the
commutator within the chamber, or casing, is not necessary, it being sufficient to
reduce the air space between the commutator, or the ring carried by it, and the
casing, to such a small amount as will prevent the passage of flame, absolute
contact between the commutator, or its ring, and the casing being avoided.
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 construction of dynamo electric-generators, or motors, having an air-
tight or nearly air tight, or flame proof case surrounding the commutator, and in
which case the brushes are whelly, or partly, contained, the other parts of the-armature
being open to the atmosphere:

page_text: Second. First. The combination of a commutator placed on the side of the bearing
remote from the armature with a casing containing the brushes and continuous with
the bearing in the manner substantially as hereinbefore described and shown in Figs. 1
and 2 of the accompanying drawings.
Third Second. The combination of a commutator with a casing containing the
brushes and a packing ring for maintaining an air tight, or flame proof joint at the
commutator surface or its equivalent in the manner substantially as hereinbefore
described and shown in Figs. 3 and 4 of the accompanying drawings.
Dated this 1st day of September 1888
F. SEATON SNOWDON,
Agent for the Applicants.

page_text: Date of Application, 2nd Dec., 1887
Complete Specification Left, 3rd Sept., 1888
Complete Specification Accepted, 5th Oct., 1888
We, WALTER THOMAS GOOLDEN, and LLEWELLYN BIRCHALL ATKINSON, both of
2 Victoria Mansions, Westminster, 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 provision of means for enclosing the brushes and commutators
of such machines so as to render them suitable for working in the presence of
inflammable or explosive gases, and under circumstances where it is necessary to
exclude the atmosphere from these parts, the improvements relating more parti-
cularly to those cases where it is not necessary or advisable to enclose the whole
armature.
In the case of a dynamo-electric generator, or motor, either of the open coil, or
close coil, type and having a commutator of few parts or so constructed as to allow of
small wires or connections being used to connect the armature coils to the segments
of the commutator, a hollow shaft may be used through which the wires or connections
pass to the commutator, placed, in this case, outside, or beyond, the bearing or journal.
When so placed the whole commutator may be enclosed, up to the journal, the brushes
and their holders being either placed completely inside the casing, or held partly
protruding in the enclosed brush holders composed of a movable or fixed casing
carrying the brush holders proper.
Should the commutator connections be too large, or for other reasons the above
method of carrying this invention into effect become undesirable then the object may
be attained by the employment of the following means.
The brushes in this case are wholly, or partly, enclosed in a casing, or chamber,
which may form part of the brush holder, and may be either fixed or movable so as to
allow of the adjustment of the brushes. The casing, or chamber, encloses the com-
mutator and has its end nearest the armature so formed as to embrace a packing ring,
analogous to the packing ring of an engine's piston rod, and .by this means the

page_text: commutator is completely isolated from the outer atmosphere. The packing material
employed would be an insulating material, asbestos being very suitable for the
purpose.
To avoid the possible short circuiting of the armature coils that might be caused by
the fine copper particles, (due to the wearing of the commutator and brushes)
becoming attached to the packing, a ring of insulating material, or of metal insulated
from it, may be suitably secured to the commutator, the packing bearing on this ring
instead of on the commutator direct.
In this case the packing may be of asbestos, metal gauze, or other material, or
spring rings may be employed for the purpose. The chamber surrounding the com-
mutator may be provided with openings for ventilation, or inspection, the openings
being protected by gauze, glass, mica or other suitable material. The chamber may
be filled with a non-supporter of combustion, such as carbonic acid gas, or it may
be arranged so as to be capable of receiving a supply of such gas should it be
necessary.
It will be understood that in certain cases an absolute air-tight packing of the
commutator within the casing, or chamber, may not be necessary, it being sufficient
to reduce the air space between the commutator, or the ring carried by it, and
the casing, to such a small amount as will prevent the passage of flame, absolute
contact between the commutator, or its ring, and the casing being avoided.
Dated this 2nd day of December 1887.

page_text: Improvements in Dynamo-electric Generators and Motors.
We, WALTER THOMAS GOOLDEN, and LLEWELLYN BIRCHALL ATKINSON, both of
2 Victoria Mansions, Westminster, London, S.W., 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 provision of means for enclosing the brushes and com-
mutators of such machines so as to render them suitable for working in the
presence of inflammable, or explosive, gases, and under circumstances where it is
necessary to exclude the atmosphere from these parts, the improvements relating
more particularly to those cases where it is not necessary, or, from the nature of its
construction, advisable to enclose the whole armature.
In the case of a dynamo electric generator, or motor, either of the open coil, or
close coil, type and having a commutator of few parts, or so constructed as to allow
of small wires or connections being used to connect the armature coils to the
segments of the commutator a hollow shaft may be used through which the wires, or
connections, pass to the commutator placed, in this case, outside, or beyond, the
bearing or journal. When so placed the whole commutator may be enclosed, up to
the journal, the brushes and their holders being either placed completely inside the
casing, or held partly protruding in the enclosed brush holders, composed of a movable
or fixed casing carrying the brush holders proper.
This method of carrying our invention into effect is shown by Figures and 2 of
the accompanying drawings, of which Fig. 1 is a side elevation partly in section, and
Fig. 2 an end elevation.
In these figures the ends of the coil wires, proceeding from the armature a,
are carried through the opening into the hollow shaft, passing through the
bearing C, and coming out to the commutator collector sections at d. When
employing brushes of the forward thrust box type they are fixed into the case
through insulating pieces i, the whole case being capable of movement round the end
of the bearing bracket C, where it is fixed, or clamped, after being properly adjusted,
by means of the bolts and nuts shown. The end of the case, is removable for
inspection or adjustment of the interior parts, a side opening k, being also provided
for the like purpose.
Should it be desired to employ brush holders swinging on pivots, or otherwise, the
case e would be so proportioned as to admit of its carrying the entire brush holders
and brushes, the same being mounted on a separate carrier which may be attached,
to the inside of the casing in any suitable manner, as will be well understood.
Should the commutator connections be too large or for other reasons the above
described method of carrying this our invention into effect become undesirable then
the object may be attained by employing the following means.
The brushes in this case are, as in the herein before described arrangement, partly,

page_text: or wholly, enclosed in a casing, or chamber, which may form part of the brush
holder, and may be either fixed or movable so as to allow of the adjustment of the
brushes.
The casing, or chamber, encloses the commutator and has its end nearest the
armature so formed as to embrace a packing ring, analogous to the packing ring of an
engine's piston rod, and by this means the commutator is completely isolated from
the outer atmosphere. The material employed for the packing ring would be an
insulating material, asbestos being a very suitable material for the purpose, while
further to avoid the possible short circuiting of the armature coils that might be
caused by the fine copper particles (due to the wearing of the commutator and
brushes) becoming attached to the packing, a ring of insulating material, or of metal
insulated from it, may be suitably secured to the commutator, the packing bearing on
this ring instead of on the commutator direct.
In this case the packing may be of asbestos, metal gauze, or other suitable material,
or spring rings may be employed for the purpose. The chamber surrounding the
commutator may be provided with openings for ventilation or inspection, the openings
being protected by gauze, glass, mica, or other suitable material. The chamber may
be fitted with a non-supporter of combustion, such as carbonic acid gas, or it may
be arranged so as to be capable of receiving a supply of such gas should it be
necessary.
This method of carrying our invention into effect is shown by Figures 3 and 4 of
the accompanying drawings, of which Fig. 3 is a side elevation, partly in section, and
Fig. 4 and end elevation.
In these figures a is the armature whose coils are connected, by the radial coil
connections, to the segments of the commutator d.
The brushes of the forward thrust box type are carried by insulating pieces i
passing through the chamber, or case, e, which as in the previously described arrange-
iment illustrated by Figs. 1 and 2, is capable of being rocked for the purpose of
altering the position of the brushes on the commutator d. On the commutator d is
placed an insulating ring f, which is securely fixed by being carried between two
inclined wedging rings g, g. The end of the case e nearest the armature is constructed
to receive a packing gland h, which on being screwed home presses on the packing
ring and so brings it into contact with, and all round, the insulating collar.
It will be understood that in this method of carrying our invention into effect
brushes of the rocking bar, or other type, may be employed, the chamber, or casing, e,
being proportionately enlarged, and suitably constructed, as was shown with reference
to the first described method.
When designed to cover, or protect, the commutators of dynamo-electric machines
having ring armatures, the insulating collar, (as shown at ƒ Fig. 3) may be carried
direct on the shaft, the wires connecting the coils on the armature with the segments
of the commutator, and which wires, in this type of machine, run parallel with the
shaft for some distance, passing through suitable holes, or slots, in the collar. By this
means the collar may be mounted direct on the shaft instead of on the commutator as
shown in Fig. 3.
It will be understood that in certain cases an absolute air tight packing of the
commutator within the chamber, or casing, is not necessary, it being sufficient to
reduce the air space between the commutator, or the ring carried by it, and the
casing, to such a small amount as will prevent the passage of flame, absolute
contact between the commutator, or its ring, and the casing being avoided.
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 construction of dynamo electric generators, or motors, having an air-
tight, or nearly air tight, or flame proof case surrounding the commutator, and in
which case the brushes are wholly, or partly, contained, the other parts of the armature
being open to the atmosphere

page_text: Second. The combination of a commutator placed on the side of the bearing remote
from the armature with a casing containing the brushes and continuous with the
bearing in the manner substantially as hereinbefore described and shown in Figs. 1
and 2 of the accompanying drawings.
Third. The combination of a commutator with a casing containing the brushes and
a packing ring for maintaining an air tight, or flame proof joint at the commutator
surface or its equivalent in the manner substantially as hereinbefore described and
shown in Figs. 3 and 4 of the accompanying drawings.