Improvements in and relating to Dynamo-electric Generators.
Year: 1896

page_text: PROVISIONAL SPECIFICATION.
Improvements in and relating to Dynamo-electric Generators.
We, CHARLES HENRY WADE, of 7 St. James's Square, Chartered Accountant,
and JAMES MOORES and HENRY OLIVER FARRELL, both of Hanging Ditch, Electri-
cal Engineers, all of Manchester, in the county of Lancaster, do hereby declare
the nature of this invention to be as follows:-
This Invention relates to mechanical generators of electric current such as may,
for example, be used in connection with a bicycle or other vehicle for producing
current for lighting an incandescent lamp or lamps of small c.p.
In carrying out our Invention we wind the armature coils upon a laminated or
ordinary core, and arrange the armature by preference between are poles of an
electro-field-magnet. This magnet may be wound in such a manner that its
coils may be in series, in shunt, or in series-shunt, as may be preferred or deter-
mined by the conditions of use. It is preferred also to construct the core of the
field magnet of parallel iron wires, or of thin sheet iron in laminae. It may be
of the horse shoe type with arc pole pieces. In a usual form of construction we
may use an ordinary double channel armature having a single coil, and arrange
the field magnet poles in segments or sections vertical to the axis of the armature
and parallel with each other, but so that on one side, commencing at one end,
each section arc is a step higher or lower than the preceding arc. On the other
side, there is a similar arrangement, but in the opposite direction, so that a higher
arc on one side is balanced by a lower one on the opposite side.
In order to obtain a fairly constant output in presence of variations of speed,
we may divide the armature coils or coil into sections, and arrange that, by means
of a centrifugal governor, a tachometer, a fan or vanes, a solenoid or differential
coils or the like, a section or successive sections of the coil may be cut out with
increase of speed and the reverse. Or we may wind the coil or coils with parallel
conductors and the reverse in like circumstances. If the speed should be con-
stant and it should be desired to allow for a variable out-put, we may deal with
the field-magnet coils in a similar manner, and so also, if the speed be variable,
to secure a fairly constant out-put.
In substitution for the ordinary brushes, we may employ spring_controlled
contact pieces: or, using brushes or their equivalent, we may employ spring
controlled equivalents for the commutator bars.
Dated this 29th day of October 1896.
W. E. HEYS & SON,
Agents for the Applicants.

page_text: Improvements in and relating to Dynamo-electric Generators.
We, CHARLES HENRY WADE, of 7 St. James's Square, Chartered Accountant,
and JAMES MOORES and HENRY OLIVER FARRELL, both of Hanging Ditch, Electri-
cal Engineers, all of Manchester, in the county of Lancaster, 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 dynamo-electric generators such as may be employed
in connection with bicycles or other vehicles for producing current for lighting
an incandescent lamp or lamps and which generators are driven from the wheels
or axles of the vehicle. The object of the invention is to ensure the production of
current having a range of voltage or pressure within narrower limits than the
limits of the variations of speed.
In a generator constructed to embody these improvements the field magnets
may be of any usual form or construction and the armature which may be of any
convenient type may be mounted within the pole pieces in any usual manner.
The armature coil or coils is or are divided into sections. Each coil is con-
tinuous in itself but at given points branches are led out and are connected to
suitable terminals. Thus, taking a coil divided into three sections as an example,
two branches are led out. When the speed is slow the whole of the coil may be
in circuit. Upon an increase of speed one of the sections is cut out and the
current is led through the first branch, thus leaving a fewer number of the coil
turns to be energised by the field magnets. Upon a further increase of speed
another section is cut out and the current is lead out through the second branch,
thus still more reducing the number of active turns of the coil. The cutting out
of the coils upon an increase of speed may be conveniently effected by means of
a centrifugal governor, a tachometer, a fan, or the like driven from the armature
or from the wheel or axle of the vehicle. Upon a decrease of speed successive
sections of the coil are put into circuit so as to increase the active number of
turns.
The accompanying drawings to which we will hereinafter refer illustrate in
what manner our invention may be carried into effect.
At one end of the armature there is a disc A of insulating material on which
are secured the two customary curved commutator bars B, and B¹ Figure 1. It
is supposed that the armature coil C is divided into two sections only as indicated
in Figures 1, 2, 3, and 4. At the back of the disc, as will be more fully described
later, are arranged three contact terminals T', T², T. One end of the armature
coil is connected to the terminal T¹ by the conductor W. From an intermediate
point in the coil a branch conductor W2 is brought out and connected to the
terminal T. The other end of the coil is connected by the wire W3 with the
commutator bar B, and the other commutator bar B is connected to the ter-
minal T3. A stud or pin P is fixed eccentrically upon the disc and carries a
spring S furnished at its end with a contact block D. This block D is capable
of movement in contact with the terminals T1, T2, T, under the influence of
variations in the speed of rotation, and is of such dimensions and form that it
must always be in contact with T3, and with either T or T2 T3 is the common
terminal from which the current is led out as indicated by Figure 3.
When the machine is running at a low speed the block D is in contact with the
terminals T, T3, and the circuit is through the whole of the armature coil, con-
ductor W, terminal T, contact block D, and terminal 13. Upon an increase of
speed, and at a point determined by the strength of the spring S, the contact
block will move and make contact with the terminals T2, T3. The circuit is now

page_text: through part only of the coil, conductor W2, terminals T2 and T3, and to com-
mufator bar B¹ as before.
The special form of contact block shewn in Figure 4 is preferably employed.
In this block are two movable pins d whose heads run upon the terminals T',
T2, T3, with which they are kept in close contact by the small spiral springs s
between the heads of the pins and the block.
The modification represented by Figure 6 differs in the number of sections
in the coil and consequently in the number of branches. The contact block may
be connected to one of the commutator bars and in this case need only come into
contact with one terminal at a time.
Other devices than the block mounted upon a spring may be employed for
making contact with successive terminals. For example a sliding block capable
of moving in a radial groove against the influence of a spring may be employed.
In place of the ordinary brushes customarily used with armature commutators
we may employ the spring controlled pins or contact pieces shewn in Figure 5.
In one form pins H, H are mounted in the support I which is parallel with the
disc A. The stems of these pins pass into or through the support and their heads
come into contact with the curved commutator bars with which they are kept in
contact by the springs . The pins may be in metallic contact with the machine
terminals M, M through the plates J, J.
In a modified arrangement bars may be placed upon the support I and the
commutator bars upon the disc A may be substituted by the spring controlled
contact pieces.
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:
1. In a dynamo-electric generator, an armature the coil of which is divided
into two or more sections any one or more of which may be cut out of circuit
upon an increase in speed and replaced in circuit upon a reduction of speed,
substantially as and by the means and for the purpose herein set forth and as
illustrated by the accompanying drawings.
2. In a dynamo-electric generator, the combination with the armature of a
contact block which moves upon an increase or decrease of speed to reduce or
increase the active number of turns of the coil upon the armature, constructed
and arranged substantially as hereinbefore described and as illustrated by the
accompanying drawings.
3. In dynamo-electric generators, spring controlled pins or the like for collect-
ing the current from the commutator bars, constructed and arranged substantially
as hereinbefore described and as illustrated by the accompanying drawings.
Dated this 20th day of July '1 1897
W. E. HEYS & SON,
Agents for the Applicants.