Improvements in and relating to Dynamo-electric Machines and Motors.
Year: 1897

page_text: Date of Application, 14th Dec., 1897-Accepted, 19th Feb., 1898
COMPLETE SPECIFICATION.
Improvements in and relating to Dynamo-electric Machines and
Motors.
We, THE BRITISH THOMSON-HOUSTON COMPANY LIMITED, of 83, Cannon
Street, in the City of London, Electrical Engineers, do hereby declare the nature
of this invention (which has been communicated to us from abroad by EDWARD
D. PRIEST, of Schenectady, in the County of Schenectady, State of New York,
United States of America) and in what manner the same is to be performed, to
be particularly described and ascertained in and by the following statement:__
The present invention relates to dynamo-electric machines, motors, and details
thereof, and more particularly to those designed for propelling vehicles upon
electric railways. Its object is to provide an electric motor specially adapted for
electric railways having increased capacity without increase of its over-all dimen-
sions.
The field magnet frame is cast in a single piece, and provided with removable frame
heads in which the armature bearings are supported, the frame heads also con-
stituting the ends of the motor. The bearings are supported from the inner faces
of the heads and extend inwards under the overhanging ends of the armature
winding and commutator shell, so that the motor presents a smooth exterior appear-
ance. By this arrangement the motor frame can occupy all of the available space
on the car truck without providing for the bearing extensions sometimes employed
on other motors.
In fully describing the invention reference will be made to the accompanying
drawings in which Fig. 1 is a side elevation of a motor embodying this invention;
Fig. 2 is a section taken on the line 2-2 of Fig. 1; Figs. 3 and 4 are detail views
showing the construction of the laminated pole pieces; Fig. 5 is a cross-section
showing the arrangement of brush holders; Fig. 6 is a sectional view showing the
construction of the ring which supports the brush holder studs; Fig. 7 is a side
elevation of the means employed in removing the armature from the motor, and
Fig. 8 is a perspective view of a field spool support.
Referring more particularly to Figs. 1 and 2, the field magnet A is shown as
cast in one piece, with short rearwardly extending lugs A¹ forming a part of the
axle bearings. Removable caps A2 are provided for the bearings, and formed
integral therewith are boxes A³ in which are placed oil and waste for lubricating
the axle B.
At the front end of the motor is a trunnion C which supports the motor by en-
gaging with a cross bar of the truck; any other of the well known means may
however be employed instead of the trunnion.
The motor has four poles, each provided with a coil D which is surrounded by
a cast metal spool D¹ protecting it from injury. Heretofore it has been customary
to divide the-field frame of electric railway.motors into two parts, either on a line

page_text: through the centres of the armature and axle, or on a diagonal. With a motor
having four wound poles and divided on the centre line, it is necessary to place
the coils at an angle of 45° with the line of division, which necessitates increasing
the distance from the centre of the armature to the under side of the motor, to
allow for the adjacent lower ends of the coils; it also necessitates increasing the
length of the motor for the same reason. When the motor is split on a diagonal,
and the coils are carried on the upper and lower parts, there are certain mechanical
reasons which make it objectionable, mainly on account of the increased cost of
machine work, and the arrangement of the bearings. By casting the field magnet
in one piece, I dispense with the joint between the parts, which increases the effici-
ency of the motor by providing a better path for the lines of force, and at the same
time the machining is decreased. Preferably laminated pole pieces E are en-
ployed similar to those shown in Figs. 3 and 4. The pole pieces consist of a
number of counter part punchings assembled and secured together by rivets E¹
and then bolted to the field magnet by bolts E2.
The inner edge of each punching is cut in two radii, one-half being concentric with
the armature and the other half gradually receding therefrom as the end is
approached. In assembling, the punchings are alternated, the non-concentric
ends of certain punchings lying between the concentric ends of adjacent punchings.
The object of this arrangement is to produce a "stiff field," so that a distinct
line of commutation will be preserved, and by gradually increasing the distance
between the armature and point e, a gradual stiffening of the field is produced
for the centre of the pole piece in both directions.
In assembling the parts of the motor, the field coils D, which have been separately
wound and insulated, are placed in their respective positions and secured by means
of the shoulders formed on the laminated pole pieces; the pole pieces being secured
by bolts E³..
In Fig. 8 is shown a slight modification of the support for the field coils. This
consists of a sheet metal punching & having upwardly extending pieces d¹ which
protect the inner surface of the field coil D (shown in dotted lines) from injury.
When punched, the pieces d¹ are in the same plane with the main body d of the
support and are formed by diagonal cuts which extend from the corners toward
the centre. These pieces are then bent backward and the shoulders thus formed
on two of the sides rest upon the shoulders formed on the removable pole pieces E,
and support the coil. By this construction, a very cheap, strong support is
obtained.
The field magnet is provided with circular removable frame heads F and F¹,
forming bearings for the armature shaft G³, which are mounted in shoulders formed
on the frame and are secured thereto by bolts L. The heads of the bolts are
partially surrounded by lugs L₁, and extending through the lugs and bolt heads
are cotter pins La preventing the bolts from turning. In addition to supporting
the bearings, the heads form the ends of the motor, and form with the field magnet
casting a completely enclosed structure. By making the heads circular, the cost
of machining is reduced to a minimum. The heads are similar in construction,
varying only in slight detail; the head F on the gear end is made greater in
diameter than the head F to facilitate the insertion of the field coils and the arma-
ture. The head Fi is provided with a projection Fª extending inwardly under the
coil support I, and forms a support for the brasses F³. The inner end of the pro-
jecting head is provided with a curved flange F5 which acts as a receptacle for oil
received from the oil thrower I' and prevents it from working outward. If however
the oil works past this flange and along the under surface of the coil support until
it reaches the flange or oil thrower I2, it will be conveyed into the receptacle F4,
which in turn communicates with the receptacle F on the outside of the motor.
A sheet iron cover F is provided which forms one side of an enclosing chamber 18
in which are placed oil and waste for lubricating the armature shaft through suit-
able holes, shown dotted in the brasses and supports. In addition to the cover F
the head F on the commutator end is provided with a cover F1, for protecting the

page_text: end of the armature shaft from dust. The cover is provided with a depression
in which is mounted a spring f. engaging with the head of the screw-threaded
stud f.
The armature G is provided with a body G¹ of laminae mounted upon a sleeve G²,
which is secured to armature shaft G³. The gear end of the sleeve is provided with
a flange G, and between it and the head J are clamped the laminae. The flange
is provided with an extension I which forms a support for the over-hanging ends of
the armature conductors. Formed integral with the coil support is the, oil
thrower I which protects the armature winding from oil from the bearing. A
second oil thrower I is also formed integral with the sleeve and throws oil into
the receptacle formed by the flange F³ of the bearing. The armature head J is
secured in place by a nut J'; and in addition to clamping the laminae, it serves as
a support for the overhanging ends of the armature conductors.
The commutator is provided with a shell K which is rigidly secured to the
shaft G. Formed integral with the shell is a beveled clamping device K¹, and
between this and the. adjustable clamp K³ are the commutator. segments. Cast
integral with the shell is an outwardly flaring flange K acting as an oil thrower
and conveying any oil which may escape from the bearing into the receptacle F.
Situated above and below the commutator are covers M and M¹; the cover M
being held in position by means of a suitable clamp M², and being removed when
it is desired to inspect the commutator and brushes. The cover M¹ is secured to
the magnet frame by bolts and is removed when it is desired to clean the motor
or inspect the lower field coil.
In Figs. 5 and 6 is shown a slight modification of the invention, in which the
field magnet frame is substantially a cube and four brush. holders are employed,
instead of two, as with the usual construction. The frame head F is circular and
mounted in a shoulder formed on the field magnet A, and is secured thereto by
bolts L. The bearing and commutator being the same as described in connection
with Figs. 1 and 2, further description is unnecessary. Bolted to the inside of
the frame head are pieces N forming supports for the grooved ring O;.. this ring
is supported in such manner that it can be rotated when it is desired to inspect
the brushes, and is normally held in the position shown by the locking device P.
As an additional support the ring is provided with a square shoulder which engages
with projection F9 on the frame head.
The brush holders are carried by the grooved ring and each is provided with
an elliptical stud Q, of metal, which is surrounded with a layer of mica or other
insulating material Q and a metal sleeve Q2. Formed integral with the stud Q
is a plate Q3 which is secured to the grooved ring by means of bolts Q*; slots Q5
being provided in the plate to permit adjusting.
The brush holder proper consists of a rectangular box or socket R having rear-
wardly projecting lugs R¹ through which the stud Q extends. It is preferred to
shrink the box or socket upon the elliptical stud, since by so doing the construction
is simplified and the cost of manufacture decreased. A lug R2 is also provided and
to this is secured the armature lead. Upon the lug R2 is formed a stud R³ having
split ends in which are mounted a pair of spiral springs R*; the springs keeping
the brushes in contact with the commutator. The outer end of each spring is pro-
vided with a handle R5 employed in raising the spring to renew the carbon brush.
To increase the conductivity between the brush and socket, a flexible metal strip R6
is secured to the socket by screw r and to the brush by a spring clip R7. This being
a four pole. machine, the top and bottom brushes are cross connected by a cable S, -
and the two side brushes by cable S¹.
To inspect the brushes and holders, the cover M is removed from the opening
at the top of the motor, the locking device P is raised; the grooved ring O can
then be rotated by hand, bringing the different brushes to the top. By, this con-
struction it will be seen that all of the brushes may be inspected and the armature
removed without disturbing the brush holders.
Referring to Fig. 7, the means for removing the armature will be described;

page_text: by any suitable means the motor is lowered into the pit below the vehicle, or other
suitable place and is placed upon the truck T. The truck consists of a base T¹
provided with wheels permitting it to travel to and fro on tracks T. The tracks
are mounted upon a suitable base which is provided with vertically extending
supports U U¹ at its outer ends. In the support U¹ is mounted a centre U2 corres-
ponding to the dead centre in a lathe, and in the support U is mounted an
adjustable centre 03 provided with a hand wheel and a locking device U. The
locking device consists of a pivoted arm engaging with notches U5 in the hub
of the hand wheel.
To remove the armature, the motor is placed upon the truck T, the latter being
moved to the left-hand side of the base, and the centre U³ is adjusted so that the
armature is supported between it and the centre U2 in the same manner as in a
lathe; the bolts L are then removed from the frame head F and the field magnet
moved to the right to the position shown. The armature is now in a position to
be examined, or it may be removed by suitable means to a more convenient place.
In some instances it is desirable to remove the pinion V and the frame head F
from the machine before removing the armature, but ordinarily the arrangement
shown would be employed.
By arranging the armature bearings so that they are substantially within the
field magnet frame and under the overhanging ends of the armature winding and
commutator shell, it becomes practicable to use a much larger motor on a standard
truck than heretofore, the field magnet being of such size that it occupies the entire
space on the truck instead of allowing for projecting bearings as commonly em-
ployed.
Though the invention is herein shown and described in combination with a rail-2
way motor, because it has its greater utility in connection therewith, it is evident
that certain of the features of the invention can be used with other kinds of motors
and generators.
Having now particularly described and ascertained the nature of the said inven-
tion (as communicated to us from abroad) and in what manner the same is to be
performed, we declare that what we claim is:
1. In an electric railway motor, the combination of a field magnet frame, a bearing
for maintaining the field magnet in alignment with the car axle, a separate frame head
at one end of the motor, said field magnet and head forming an enclosed structure
protecting the armature and commutator, and armature bearings extending under 3
the projecting parts of the armature.
2. In an electric motor, the combination of an iron clad field magnet frame
enclosing the armature and commutator; with an armature having a winding of
the barrel form with ends projecting beyond the body of laminae and supports for
the projecting ends of the winding, and an inwardly projecting armature bearing 4
on the gear end of the motor beneath the adjacent winding support, as set forth.
3. In an electric motor, the combination of a field magnet frame, an armature
having a winding with an overhanging end, a coil support for the overhanging end of
the winding, a commutator liaving an outwardly flaring shell, and armature bear-
ing projecting under the coil support and commutator shell.
4. In an armature, the combination of a body of laminae, a sleeve to which the
laminae are secured, a shaft rotating with the sleeve, and an oil thrower or throwers
formed integral with the sleeve.
4
5. In a commutator for a dynamo electric machine, the combination with a shell
which is rigidly secured to a moving part of the machine, a clamping device formed 5
integral therewith, an adjustable clamp, and an outwardly flaring flange on the
shell acting as an oil thrower.
6. In an electric motor, the combination of a field magnet frame cast in one
piece and supported by suitable bearings upon the car axle, an armature, circular
removable frame heads, armature bearings mounted therein, and a receptacle or 5

page_text: chamber on the frame head adapted to receive the oil which works: outward from
the bearing.
7. In an electric motor, the combination of a field magnet frame cast in one piece,
a sleeve upon which the armature laminae are supported, a shaft rigidly connected
to the sleeve, a flange formed on the sleeve against which the laminae abut, a coil
support formed integral with the sleeve, an oil thrower also formed on the sleeve,
and a, removable frame head provided with a bearing which projects under the
end of the sleeve and coil support.
8. In a dynamo electric machine, the combination of a cast field magnet, and
laminated removable pole tips secured thereto, the laminae consisting of counter-
part punchings each having one half of its face concentric with the armature and
the other half curved on a larger radius towards the pole tip.
9. In a dynamo electric machine, the combination of a cast field magnet,
laminated removable pole pieces bolted thereto, the laminae consisting of counter
part punchings each having one half of its face concentric with the armature,
and the other half describing an are of a circle which is non-concentric with the
armature, the laminae being assembled so that non-concentric ends of certain
laminae are between the concentric ends of adjacent laminae.
10. In a dynamo electric machine, the combination of an enclosing field magnet,
an armature, removable frame heads enclosing the end of the motor, projections
upon the heads forming supports for the armature bearings a ring mounted for
rotary movement upon one of the heads, and brush holders carried by the ring.
11. In a dynamo electric machine, the combination of an enclosing field magnet
frame, an armature, removable frame heads forming supports for the armature
bearings, a ring mounted for rotary movement upon one of the heads, elliptical
brush holder studs secured to the ring, and surrounded by insulation, and brush
sockets shrunk upon the studs.
12. In a brush holder, the combination of an elliptical stud, a support therefor,
a brush socket, a lug thercon for securing the socket to the stud, spiral springs
engaging with the brushes mounted in the sockets, and a stud to which the springs
are secured.
13. In a device for removing armatures from motors, the combination of a base,
tracks upon the base, a motor carriage adapted to travel on the tracks, standards
secured to the base, a fixed centre mounted in one of the standards and adapted
to extend through the motor when the armature is removed, and an adjustable
centre mounted in the other standard, the arrangement of centres being such that
the motor armature is supported between them when the motor frame is moved in
a direction to uncover the armature.
14. In a dynamo electric machine having a removable pole piece, the combination
of an energizing coil and a support therefor consisting of a sheet metal punching
having upwardly extending pieces formed integral therewith, the pieces protecting
the inner portion of the coil from the pole and the main body of the punching
the bottom of the coil.
15. An electric motor having an iron clad field magnet frame, an armature and
commutator having overhanging surfaces at opposite sides of the motor, and bear-
ings for the armature shaft extending inward and underneath the overhanging
portions of the armature and commutator, whereby space in the direction of the
armature shaft is economised, as set forth.
16. In an electric motor of the iron clad type, the combination of an armature
having an overhanging end projecting from the core, a field magnet, and a bearing
for the armature shaft extending inward and underneath said overhanging end of
the armature.
17. In an electric railway motor, the combination of a field magnet, bearings
for maintaining it in alignment with the car axle, separate frame heads at the
ends of the motor, armature bearings extending under the projecting parts of the
armature, and separated there from by a space, and an oil conveyer or thrower
located between the bearings and the armature.

page_text: 18. In a brush holder, the combination of a metal stud; a layer of insulation,....
surrounding the stud, a metal sleeve surrounding the insulation, a brush box.
shrunk upon the stud, and a spring for applying pressure to the brush....
LAYA
For the Applicants,
J. C. CHAPMAN,
Chartered Patent Agent,
70, Chancery. Lane, London, W.C::
BOTAA TAA
For the Applicants,
J. C. CHAPMAN,
Chartered Patent Agent,
70, Chancery. Lane, London, W.C: