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

page_text: Date of Application, 21st July, 1887
Complete Left, 19th May, 1888
Complete Accepted, 21st July, 1888
Improvements in Dynamo-electric Generators and Motors.
We, H. C. BULL & COMPANY, Limited and HENRY CLAY BULL, Engineer, both
of 31, Poultry, London do hereby declare the nature of the said invention to be as
follows:-
According to this Invention dynamos are provided with a novel form of the electro
magnet whereby the lines of force are caused to move all in one way. This is
accomplished by having the magnets in two parts, that is to say each magnet is in
the form of an ordinary magnet divided into two parts either at the centre, or at a
reasonable distance from it and on the side of the magnet where the metal has been
removed any non conducting substance is substituted for one of the parts of the
magnet. One of the portions and the non conducting material is wound with the
conducting wire and the other portion of the magnet which has been removed is
securely fastened against the outside coils. This arrangement brings one face of the
magnet close against the coils while the other face of the magnet is separated from
the coils by the non conducting substance and the other portion, or half of the
magnet, as the case may be, has its active face pressed tightly against the outside of
the coils near the non conducting substance.
The effect of this arrangement is to cause the lines of force to move always in one
direction, thus dispensing with the use of commutators in either a dynamo or motor
constructed on these lines.
In providing a dynamo, or motor with this magnet we prefer to construct them as
follows: The motor or dynamo shaft is fitted in suitable bearing boxes to admit of
them running at a high velocity. In between these bearing boxes is a hollow iron,
or steel cylinder which also has a pair of bearing boxes outside the shaft. The
journals on this cylinder are hollow and of. sufficient size to in no way touch the

page_text: driving shaft. In connection with this cylinder which may be of any convenient
length, or diameter there are provided any number of the magnets surrounding its
outer circumference. The cylinder receives its movement when acting as a dynamo,
or delivers its movement when acting as a motor to the driving shaft through the
medium of a dog of non-conducting material arranged similarly to the driving dog
used in turning in a lathe. The cylinder is turned perfectly true and straight. The
inner, or active faces of the magnets are bored out perfectly true. This admits
of the surfaces moving very closely together without touching and as there are no
coils whatever wound on the inner cylinder a very high rate of speed can be obtained
without danger to the machine.
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1
H. C. BULL & COMPANY, LIMITED.
HENRY CLAY BULL.
By Cheesbrough & Royston,
Agents.
COMPLETE SPECIFICATION.
Improvements in Dynamo-electric Generators and Motors.
We, H. C. BULL AND COMPANY Limited and HENRY CLAY BULL, Engineer, both
of 31 Poultry, London, do hereby declare the nature of the said invention and in
what manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :—
2
According to this Invention dynamo-electric generators or motors are provided
with a novel form of electro field magnet in which the lines of force are caused to
move all in one way. This is accomplished by having the magnets in two parts, that
is to say each magnet is in the form of an ordinary magnet divided into two parts
either at the centre or at a reasonabl distance from it; and on the side of the magnet-
where the metal has been removed any non-conducting substance substituted for one
of the parts of the magnet, one of the said portions, and the non-conducting material,
is wound with the conducting wire and the other portion of the magnet which has
been removed is securely fastened against the outside coils.
This arrangement brings one face of the magnet close against the coils, while the
other face of the magnet is seperated from the coils by the non conducting substance,
and the other portion, or half of the magnet, as the case may be, has its active

page_text: face pressed tightly against the outside of the coils near the non-conducting
substance.
The effect of this arrangement is to cause the lines of force to move always in one
.direction, thus dispensing with the use of commutators, in either, a dynamo, or motor
constructed on these lines.
In providing a dynamo or motor with this magnet, it is preferred to construct them
as follows: The motor or dynamo, shaft is fitted in suitable bearing boxes to admit
of them running at a high velocity.
In between these bearing boxes is a hollow iron or steel cylinder, which also has
a pair c" bearing boxes outside the shaft. The journals on this cylinder are hollow
and of sufficient size to in no way touch the driving shaft. In connection with this
cylinder, which may be of any convenient length, or diameter there are provided any
number of the magnets surrounding its outer circumference.
The cylinder receives its movement, when acting as a dynamo, or delivers its
movement, when acting as a motor through the driving shaft, through the medium
of a dog of non conducting material, arranged similarly to the driving dog used in
turning in a lathe. The cylinder is turned perfectly true and straight.
The inner, or active faces of the magnets are bored out perfectly true.
This admits of the surface of the cylinder moving very closely to the magnets
without touching, and as there are no coils whatever wound on the inner cylinder, a
very high rate of speed can be obtained without danger to the machine.
The magnets are wound with wire in any known suitable manner.
For instance,
for high tension they are wound in series and the current passed around all in series.
For light tension the magnets may be wound in seperate series of two or more
magnets each.
In the case in which all the magnets are wound in series the return wire to the
machine passes round the first magnet, and then round each magnet in series and
serves as the main lead after leaving the last magnet.
A machine embodying the above described construction and arrangement of parts
is illustrated in the annexed sheets of drawings which together with the following
description of same, and the foregoing description of this invention, are sufficient to
enable others skilled in the art to which this invention belongs, to make and put the
same into practice.
The drawings form part of this Specification, and are marked with figures and
letters of reference, which correspond with those used in the following explanation.
Likė letters and figures are used to denote like parts throughout the views.
With reference to the Drawings
Figure 1 is a sectional elevation of a machine provided with improvements
according to this invention.
Figure 2, is a section through the line of the machine shown in figure 1, and
Figure 3 is. a plan of the machine. In the drawing, A designates field magnets
which are arranged in three sets of three each; B is the iron or steel cylinder, the
ends 6 of which are mounted in bearings b'; C is the shaft of the machine which is
mounted in bearings D, and one of the ends carries a disc d. This disc is provided
with a dog d¹, of non-conducting material which also fits into the dise 62 formed upon
the journal of one of the covers b. The bearings b¹ are insulated from the bed E by
non-conducting material e. It will be observed that the shaft C is placed con-
centrically in the journals of the covers b, but does not touch them. Hence the
cylinder B is entirely insulated.
The magnets A are held by clamps a, which are placed on both sides of them.
Between the clamps and the magnets non-conducting material is provided for the
purpose of insulating the latter from the clamps, F are frames secured to the bed E
and provided to support and secure the clamps a. This is effected by bolts and nuts
which pass through the frames F and flanges formed on the clamps a.
A divided magnet A consists partly of a metallic core a¹ and partly of non-
conducting material a², around which a coil of wire a³, is wound, and outside of this
coil and on the side next the non-conducting material, the second portion a* of the

page_text: +
metallic core is placed. The three portions a¹ a³, a and the coil a³, which constitute
a magnet A, are held in position by the clamps a as above described. The core a¹ is
grooved externally so as to recieve the coils a³ and bears upon the part a².
All the electricity generated or used by the machine is passed through the coil a³.
The external piece a*, of the magnet is also grooved to fit over the coil a³, as shown.
The cylinder B as above named, is turned true and straight, and the inner, or
active faces of the magnets A are bored out correspondingly true this admits of the
surface of the cylinder moving very closely to the magnets without touching. The
effect of the construction of magnets above described is to cause the electric lines of
force to move in one direction only, thereby rendering the use of commutators
unnecessary, in either a dynamo-electric generator, or motor constructed on the lines
herein specified. The construction of the cylinder B and the arrangement of
magnets thereto permits of a high rate of speed being obtained without danger to the
machine.
To generate a current the cylinder is revolved at a high velocity the electricity
thereby generated being passed through the coils of the magnets as described; and
conversely, to use the machine as an electric motor the electricity is supplied to the
coils of the magnets and the cylinder B is thereby rotated: from the shaft of the
cylinder the power may be transmitted in any known way.
Having now particularly described and ascertained the nature of this Invention and
in what manner the same is to be performed what is claimed is :
First. In dynamo-electric generators or motors, magnets constructed with cores
consisting of a metallic piece and a piece of non-conducting substance, such metallic
and non-conducting pieces being wound with a wire coil and a second metallic piece
placed outside the said coil and against the non-conducting piece; as, or substantially
as and for the purposes set forth.
Second. The dynamo electric generator or motor, herein described with reference
to the drawings, consisting essentially of a series of magnets A, constructed as
described, and a rotary cylinder B; operating and constructed as or substantially as
set forth.
H. C. BULL & Co., LTD.
HENRY CLAY BULL.
By Cheesbrough & Royston,
15, Water Street, Liverpool,
Patent Agents.