IMPROVEMENTS IN MAGNETO-ELECTRIC MACHINES
Year: 1877

page_text: LETTERS PATENT to William Robert Lake of the firm of Haseltine Lake
& C° Patent Agents Southampton Buildings London for an Invention of
"IMPROVEMENTS IN MAGNETO-ELECTRIC MACHINES communicated to him from
Abroad by Edward Weston of Newark New Jersey United States of America.
"
PROVISIONAL SPECIFICATION left by the said William Robert Lake at
the Office of the Commissioners of Patents on the 14th December 1877.
WILLIAM ROBERT LAKE of the firm of Haseltine Lake & C° Patent
Agents Southampton Buildings London "IMPROVEMENTS IN MAGNETO-ELECTRIC
MACHINES [A Communication to him from Abroad by Edward Weston of
Newark New Jersey United States of America.]
"
This Invention relates to certain improvements in the machine described in the
Specification of former Letters Patent dated the 6th day of November A.D. 1876
N° 4280
The said Improvements comprise the combination, with a commutator as described
in the said former Specification, of two brushes attached to a pivotted disc whose
axis coincides with the axis of the commutator-shaft, the disc being provided with
one or more set-screws whereby it may be clamped in variable positions for the
purpose of regulating the strength of the current."
The present improvements also relate to a device for automatically closing and
breaking the circuit which device is constructed as follows that is to say. A disc
is attached to a shaft which has its bearing in the end of a pillar and is rotated by
means of a belt from the shaft of the machine to a pulley placed in a suitable
position. The said disc is provided with two radial slots each of which contains a
sliding switch-block which is pressed inward toward the axis of the disc by an
adjustable spiral spring
The shaft to which the said disc is attached projects outward from the disc and
is covered with a shell constructed of wood or other suitable non-conducting

page_text: This
material to answer the purpose of an insulator Upon the outside of the said shell
there is a metallic hub against the periphery of which the said switch-blocks rest
when they yield to the action of the said spiral springs. A brush is attached to
another pillar and constantly beais upon the periphery of the said hub.
pillar is connected by means of a wire with one line wire and the first named pillar
is connected by means of a wire with the other line wire both of these connections
being made between the machine and the vat or vessel used for containing the
solution in the electro-plating or electro-typing process. When therefore the machine
is at rest or when its speed falls to a prescribed point the said switch-blocks form
an electrical contact with the said hub and the electrodes are thus provided with a
short circuit through a portion of the line wires and through the first named con-
necting wire to the pillars, brush, hub, switch blocks, disc, and the other said
connecting wire
In this arrangement the main circuit which includes the machine and the vat or
vessel is always unbroken but the short circuit which includes the circuit closer
and breaker and its connections present so much less resistance than that presented
by the wire forming the coils in the machine that the current from the electrodes is
nearly all discharged by the short circuit and no sufficient portion of it to effect the
polarization of the magnets can reach the machine. On the contrary, when the
machine has acquired the desired rate of speed centrifugal force acting upon the
switch-blocks throws them out of contact with the said hub and thus breaks the
short circuit and compels the operative current from the machine to pass through
the electro-plating or electro-typing vat or vessel
With regard to the device described in the said former Specification for effecting
the same objects by using mercury I desire to point out that any suitable con-
ducting fluid may be used if found desirable in place of the mercury.
The said improvements also relate to another mode of preventing the change of
polarity of the inagnets which is carried into practice as follows that is to say.
The line wires of the machine are permanently connected by a bridge-wire which
includes a resistance-coil-By means of this bridge-wire or "shunt" the machine is
always provided with a short circuit and the electro-magnets are therefore kept
constantly excited but when the operative circuit is closed the larger portion of the
current generated by the machine passes through the operative circuit because of
the excessive resistance in the short circuit-For the purpose of electro-deposition
I may use another device in combination with a dynamo-electric machine and an
electro plating or electro typing solution
The said device consists of a moveable armature capable of forming a section of
either circuit and held in the short circuit by a spring or weight until withdrawn
therefrom and placed in electrical connection with the long loop by the attraction
of an electro-magnet excited by the current from the machine. The current is by
this means diverted from one circuit into another.
In my improved machine I construct the soft iron cores of the magnets, hollow, for
the admission of a stream of water or air for the purpose of keeping the magnets
cool. The said hollow cores may be connected with a water supply or if the
machine works in water, openings may be provided to admit water to the magnet
cores.
I sometimes construct an outer shield or case which is water-tight and encloses
the magnets and armatures. Then by first coating the machine with paraffine or
other suitable insulating material I am enabled to work the armatures in water and
thus keep the machine cool-The said shield or case forms a chamber through
which a circulation of water may be maintained by means of an induction pipe at
the bottom and an eduction pipe at the top or by any other suitable means.
the machine as formerly constructed and as described in the said former Specification
the bearing of the shaft at the commutator end was placed outside the conmutator
but in my improved machine the commutator is placed outside which arrangement
facilitates removal for cleaning or otherwise
In

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Robert Lake in the Great Seal Patent Office on the
13th June 1878.
WILLIAM ROBERT LAKE of the firm of Haseltine Lake & Co Patent
Agents Southampton Buildings London "IMPROVEMENTS IN MAGNETO-ELECTRIC
MACHINES"-A communication to me from abroad by Edward Weston of Newark,
New Jersey, United States of America
This invention relates to certain improvements in the machine described in the
specification of former Letters Patent dated 6th day of November A.D. 1876 N° 4280.
The said improvements are as follows
First the combination with a commutator as described in the specification of
the said former letters Patent, of two brushes attached to a pivoted disc whose
axis coincides with the axis of the commutator-shaft, the disc being provided with
several concentrically curved slots for the admission of set-screws by means of
which the disc, and consequently the brushes, may be clamped in variable positions
for the purpose of regulating the strength of the current, the range of adjustment
of the disc, and consequently of the brushes being limited to the distance between
the position where the current obtainable from the machine will be of the lowest
strength and the position where such current will be of its highest strength.
The second feature of the present improvements relates to devices for auto-
matically closing and breaking the circuit and which consist substantially of a
rotating disc provided with two radial slots containing sliding switch-blocks, which
are pressed inward toward the axis of the disc by adjustable spiral springs.
The shaft to which the disc is attached is provided with a suitable bearing in the
upper end of a metallic pillar and at one end has a pulley by means of which it
is rotated. At the other end the shaft projects outward from the disc and is
covered with a sbell of wood or other suitable insulating material whereon there
is mounted a metallic hub against the periphery of which hub the switch-blocks
rest when they occupy the position due to the preponderating influence upon them
of the spiral springs. A brush attached to a vertical pillar is made to bear con-
stantly upon the periphery of this insulated hub and is electrically connected with
one line wire, while the pillar supporting the shaft of the disc is electrically
connected with the other line wire both of these connections being made between
the machine and the vat used for containing the electrolytic solution. When the
machine is at rest or whenever its speed falls to a prescribed point, the switch-
blocks in consequence of the action upon them of the spiral springs, form an
electrical contact with the hub, and the electrodes in the vat are thus provided
with a short circuit through a portion of the main line wires and through the
connecting wires to the pillars which support the rotating disc and the brush that
bears upon the hub. "In this arrangement the main circuit which includes the
machine and the electro-plating vat is always unbroken but the short circuit or
bridge which includes the circuit closer and breaker presents when closed so much
less resistance than that presented by the wire forming the coils in the machine,
that any reverse current from the electrodes in the vat is nearly all discharged by
the short circuit or bridge and no portion of it sufficient to effect the polarization
of the magnets can reach the machine. On the contrary, when the machine has
acquired a pre-determined speed of rotation, centrifugal force acting upon the switch-
blocks throws them out of contact with the hub and thus breaks the short circuit
and compels the entire current from the machine to pass through the electro plating
or electro-typing vat or vessel.
The third feature of these improvements also relates to the preservation of the
polarity of the magnets in the machine and consists in combining with the main
or operative circuit of the same a constantly closed differential circuit of prescribed

page_text: resistance. This object is conveniently effected by a bridge connecting the two
line-wires and including a resistance-coil. By means of this bridge or shunt
the machine is provided with a constantly closed short circuit which keeps the
electro-magnets in the said machine constantly excited. When the operative circuit is
closed the larger portion of the current generated by the machine passes through
the operative circuit because of the excessive resistance in the short circuit. The
short circuit or bridge containing the resistance coil may be advantageously
employed in connection with another bridge containing an automatic circuit closer
and breaker either such as herein described or like that described in my former
specification in which the object is accomplished by using a rotating cup containing
mercury the mercury assuming a position either in or out of the circuit according
to whether it occupies the position due to the preponderating influence upon it
of gravity simply, or whether it occupies another position induced by the
preponderating influence upon it of the centrifugal forces generated by its own
rapid rotation.
Any suitable conducting fluid may be used in place of the mercury.
The fourth feature of the said improvements relates to a device for koeping the
machine cool when in operation and consists in the use of magnets having hollow
cores connected with water-supply pipes by means of which a circulation of water
is maintained through the said cores.
The fifth feature of the said improvements also relates to a device for keeping
the machine cool and consists in coating the interior parts of the said machine
with paraffine or other suitable insulating material and in arranging the parts in
a water-tight shell provided with an induction-pipe at the bottom and an eduction
pipe at the top by means of which pipes a circulation of cold water is maintained
through the shell.
The first part of this invention is shown in figures 1 and 3. Figure 1 is a side
view of an improved dynamo-electric machine constructed according to this
invention showing the said machine partly in central vertical longitudinal section.
Figure 3 is a front view of the same.
The said machine has a cylindrical iron shell A supported on a suitable bed-
plate A¹, and closed at the ends by the heads a, and b, which are secured to the
cylinder by means of the screws a¹ and b¹. These heads are centrally perforated to
afford bearings for the shaft C. The driving pulley c, is fixed on one end of the
shaft C and the commutator D is fixed on the other end. The commutator is like
that described and shewn in my said former specification and currents are collected
from the commutator by means of two brushes E and E'. Those brushes are
secured in bosses e, e', cast upon the cylinder-head a and the screws by which
the cylinder-head is fastened to the cylinder pass through concentric slots a²,
in the cylinder-head a. By loosening the screws a² the cylinder-head a may
be turned back and forth upon its axis, the range of its motion being limited
by the length of the slots a³. The brushes being affixed to the head a move with
it and are hence capable of simultaneous adjustment by the turning of the cylinder-
head a. The rotating armature F and the stationary electro-magnets G, G, in the
interior of the machine have the same relation to each other as those shown in the
specification of my former letters patent. The holding screws a¹ and the slots a²,
are so arranged with reference to the position of the brushes and to the positions
of the stationary electro-magnets G that when the screws a' are in contact with
one end of the slots a³ the current collected by the brushes from the commutator is
of the lowest strength and when the screws a³, are in contact with the other end of
the slots a³, the current collected by the brushes from the commutator is of the
highest attainable strength.
The second part of this invention is shewn in side elevation in figure 1 and in
front elevation in figure 2. It consists of a rotating disc H mounted in the upper
end of a metallic post H³, the base of which is electrically connected with one of
the binding posts J of the machine. The disc H, is provided with two radial
slots h each of which contains a switch-block ¹. Each switch-block is pressed

page_text: toward the centre of the disc by the expanding spiral springs h³ which are
adjustable by means of the set-screws h³. The switch-blocks project outwardly
from the face of the disc, and when the apparatus is stationary form an electrical
contact with the hub I which is supported on a bushing 1' of insulating material
covering the projecting portion of the shaft whereon the disc H is mounted.
Another metallic post i electrically connected with the other binding post j
supports a brush which bears constantly upon the periphery of the hub I.
When therefore the switch-blocks are in contact with the hub a continuous
electrical connection is made from one binding post to the other through the
brush, hub I switch-blocks h³, disc H and post H. The disc-shaft is provided
with the driving pulley H³, and the disc is rotated by means of the belt H which
is driven by the pulley Hon the main shaft C of the machine. The spiral springs h
are so adjusted that when the machine, and consequently the disc H, is rotated at
a predetermined rate of speed, centrifugal force acting upon the switch-blocks
throws them outward and thus breaks the electrical connection between the
posts and i. The binding posts J and ; are connected by means of the
wires J, J, and with the machine, this connection being for convenience made
on the under side of the bed-plate A' as shown in figure 6. The line wires K, k
of the operative circuit are connected in the usual way with those portions of the
binding posts which project above the bed-plate. It will thus be seen that this
mechanical circuit closer and breaker is not contained in the operative circuit but
acts either to open or close a short circuit between the binding posts, the resistance
of which is so small compared with that portion of the circuit composing the coils
surrounding the electro-magnets in the machine, that the greater part of any
reverse current from the electrodes with which the machine may be in circuit will
pass through the short circuit in preference to passing through the coils surrounding
the magnets in the machine.
The third feature of this invention is illustrated in figure G which is a view of
the underside of the bed-plate A¹ of the machine, and shows the bases of the
binding posts J and j and of the posts i and H', which belong to the said
mechanical circuit closer and breaker. It will be seen that the two binding posts
are electrically connected by means of the wires L, and the opposite ends of the
resistance coil M. If therefore the operative circuit should from any cause be
broken, the current from the machine is afforded a path through the constantly
closed circuit containing the resistance coil M.
This constantly closed circuit or bridge connecting the wires of the operative
circuit has such great resistance by reason of the inclusion in it of the coil M
that when the operative circuit is closed no material portion of the operative
current is diverted from the operative circuit.
and
The fourth feature of the said invention is illustrated in Figures 4 and 5.
Figure 4 is a side view of one of the electro-magnets in the said machine;
Figure 5 is a transverse section through the line x, x in Figure 4. The cone N
of the magnet is made hollow to form the interior chamber n. This chamber is
provided with two pipes n', n' connected with a water supply and by means of
which a circulation of cold water is maintained within the chamber n when the
machine is in operation.
The fifth part of the said Invention consists in coating the interior parts of tho
machine-that is to say, the armaturo F and the stationary electro-magnets G, with
paraffine or other suitable insulating material and in making the cylinder in which
the magnets are contained water tight by means of the packing rings O O' Figure 1
between the heads a and b and the ends of the cylinder and by providing the
cylinder with the induction pipe o and the eduction pipe o' by means of which u
circulation of water is maintained through the said cylinder when the machine is in
operation
Having thus fully described the said invention as communicated to me by my
Foreign Correspondent and the manner of performing the same I wish it understood
that I Claim in a dynamo-electric machine.

page_text: First Two or more brushes for collecting currents of electricity from a rotating
commutator and deriving their support from a disc having a definitely limited
capacity of adjustment upon an axis coinciding with the axis of the commutator,
as above described.
Secondly The radially slotted disc mounted upon a shaft rotated by the
machine or by the power which drives the same, and which is provided with the
moveable switch-blocks and the insulated hub in combination with a brush
affixed to the upper end of a standard, as and for the purpose set forth.
Thirdly The combination of the main or operative circuit of a dynamo-electric
machine with two bridges each electrically connecting the two wires of the main
circuit, one bridge containing a resistance-coil and affording a constantly closed
differential circuit of pre-determined resistance, and the other bridge containing a
contact maker and breaker, as above described.
Fourthly The combination of magnets having hollow cores with water-supply
pipes, by means of which a circulation of water is maintained through such cores
for the purpose of keeping them cool when the machine is in operation.
Fifthly The method of preventing the overheating of dynamo-electric machines
by coating the interior parts of the machine with paraffine or other suitable
insulating material and enclosing such coated parts in a water-tight chamber pro-
vided with an induction and eduction pipe, by means of which a circulation of
cold water is maintained in and through such chamber, while the machine is being
operated.
In witness whereof I the said William Robert Lake have hereunto set my hand
and seal this Twelfth day of June in the Year Of Our Lord One thousand eight
hundred and seventy eight.