Improvements in Dynamo-electric Generators and Motors.
Year: 1889

page_text: Date of Application, 17th Apr., 1889
Complete Specification Left, 13th Jan., 1890-Accepted, 15th Feb., 1890
PROVISIONAL SPECIFICATION.
Improvements in Dynamo-electric Generators and Motors.
I, GEORGE EDENSOR DORMAN, of The Hawthorns, Stafford, in the County of
Stafford, Engineer, do hereby declare the nature of this invention to be as
follows:-
The object of my invention is by a more suitable disposition of materials than
heretofore employed, to considerably reduce the weight of iron and copper entering
into the construction of dynamoelectric generators and motors, to reduce the space
occupied by said machines, at the same time employing a simple and economical mode
of construction specially adapted to be made in cast iron. A dynamoelectric generator
or motor made according to my invention consists of cast iron tube, cast in halves,
cach half being bolted to the other half by means of lugs or flanges cast on the
exterior of said half tubes, on the interior of each half tube and centrally located a
pole piece being cast, and on the ends of each half tube a bracket or plate being cast
which may partially or completely enclose the ends of its half tube, said brackets
containing half of a boss, which when the two half tubes are bolted together I bore
out, at the same time or at the same setting at which the pole pieces are. bored out,
thus ensuring centrality of an armature to be supported between the pole pieces,
the shaft of said armature being supported in journals or bushes fixed in aforesaid
bosses.
Around the pole pieces within said cast iron half tubes I place exciting coils
previously wound and taped and afterwards bent or compressed in a mould or other-
wise, to exactly fit the curvature of the interior of the cast iron half tubes around said
pole pieces, the coils being made in one or for convenience in bending or compressing
in two or more sections, and one or more sections may be larger than the other
section or sections in the same coil, the coils thus made as nearly as possible except
where the pole pieces are situate filling the annular space formed between the
armature and cast iron tubes when the machine is put together. And in order to
prevent the coils from approaching too nearly to the armature I interpose curved
plates of brass or other suitable material connected or retained in place by end
cylinders. On the exterior of one of the half tubes, lugs or flanges or brackets being
cast to attach the machine to a base or foundation rails.
Dated this 16th day of April 1889
GEORGE EDENSOR DURMAN.
COMPLETE SPECIFICATION.
Improvements in Dynamo-electric Generators and Motors.
I, GEORGE EDENSOR DORMAN, of The Hawthorns. Stafford, in the County of
Stafford, Engineer, 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:-
The object of my invention is by a more suitable disposition of materials than
heretofore employed, to considerably reduce the weight of iron and copper entering
into the construction of dynamoelectric generators and motors, to reduce the space
occupied by the said machines at the same time employing a simple and economical
mode of construction. My invention being specially adapted to dynamoelectric
generators and motors in which the main structure of the machine is made in
cast iron.

page_text: A dynamoelectric generator or motor made according to my invention consists of a
cast iron tube, cast in halves, each half being bolted to the other by means of lugs or
flanges cast on the exterior of the said half tubes, on the interior, of each half tube
and centrally located a pole piece being cast, and on the ends of each half tube a
bracket or plate being cast, which may partially or completely enclose the ends of its
half tube, the said brackets containing the half of a boss, which when the two half
tubes are bolted together I bore out, at the same time or with the same cutter, at, or
with which the pole pieces are bored, thus ensuring the centrality of an armature to
be supported between the pole pieces, the shaft of the said armature being supported
in journals or bushes fixed in the aforesaid bosses.
Around the pole pieces within the said cast iron half tubes I place exciting coils,
previously wound, varnished and taped or insulated, and bent, or compressed, in a
mould or otherwise to exactly fit the curvature of the interior of the cast iron half
tubes, the coils being made in one, or for convenience in bending, or compressing in
two or more sections, and one or more sections may be larger, than the other section
or sections in the same coil, the coils thus made, as nearly as possible except where
the pole pieces are situated, filling the annular space formed between the armature
and cast iron tubes, when the machine is put together.
In order to prevent the coils from approaching too nearly to the armature I arrange
retaining rings of brass or other suitable material on either side of the pole pieces, the
said rings supporting the coils.
On the exterior of one of the half tubes iugs or flanges or feet being cast, to attach
the machine to a base or to foundation rails.
In the accompanying drawings, Figure 1 is a sectional view through the pole pieces
of a dynamoelectric generator or motor made according to this invention. Figure 2
is an end view shewing the field coils and journal bushes. Figure 3 is a side view
and partial longitudinal section shewing the field coils and journal bushes. Figure 4
is a plan of one half tube or casting, shewing the field coils in place around the pole
piece, and the retaining rings on either side of the said pole pieces. Figure 5 is an
end view of one of the sections of the field coils.
In the figures a, indicates the field coils, the retaining rings for supporting the
same, the various sections of the bent field coils being all of the same diameter or
each section being larger as it is more distant from the armature, as is shewn in the
figures. When the sections are of the same diameter, in order to fill the annular
space between the armature and tube as much as possible, which is preferable, to
secure the best results the sections should be of the same diameter as the coil or
section on the respective pole pieces, nearest the armature, this pair of coils being
preferably made to embrace the armature as completely as possible.
When the sections are all of the same diameter a short tube but of large diameter
and with deep pole pieces will be requiredto accomodate the necessaryamount of wire
or coils as compared with the construction in which each section is made of as large a
diameter as possible.
A commutator is shewn at d, when the end brackets K and M both enclose the
ends of the half tubes as at M, so that brushes of the normal type could not be
approached, brushes may be used which are fed through rectangular tubes to the
commutator,such tubes passing through suitable holes or slots in the castingsbut when
as is shewn in Figure 3, the bracket K is sufficiently open, rocking yoke and brushes
of ordinary type may be employed.
As the brackets K and M form part of the magnetic circuit of the machine, in order
to give the least resistance to the lines of force, they are preferably made to completely
enclose the ends of the half tubesfas shewn at M, this being additionally advantageous
in excluding damp or dust from the field coils and armature.
When economy in space and weight is desirable the corners ras seen in Figure 4
may be rounded so as to follow the contour of the field coils a.
The castings may be made in pure iron or any of its alloys with carbon or aluminium
when desirable or possible.

page_text: 6th. In a dynamoelectric generator or motor an iron tube or equivalent structure
cast in halves, the said tube containing two interior pole pieces, bent field or exciting
coils, around the said pole pieces,and having end brackets cast integral with oach half
tube,one or both ends of the said tube being completely enclosed by the said brackets,
substantially as herein described and shewn.
1000