Year: 1898

page_text: I, REGINALD BELFIELD, of 32, Victoria Street, in the City of Westminster,
Electrician, do hereby declare the nature of this invention to be as follows :-
The invention relates to controllers for electric motors and particularly to that class
of controllers which embody means for controlling the power and speed of motors
employed for propelling railway vehicles, and also means for so arranging and regulat-
ing the circuits of the motors that they may act as generators and thus produce a
braking effect such is necessary to reduce the speed of and bring to rest the vehicle
which is normally propelled by them when acting as motors.
According to the present invention the controller is constructed with two switches
one of which is operated to vary the resistance in circuit with the motors and to
change the connection when the motors are supplied with electric current, the
positions of the switch under these conditions being conveniently designated "power"
positions; this main switch is further-more arranged to connect the motors in parallel
in a closed local circuit and to vary the resistance in such circuit when external
sources of current have been cut off, the motors in such case acting as generators and
exerting a powerful braking effect, these latter positions of the switch are called
"braking" positions. The second of the two switches in the controller consists of a
two part reversing switch constructed so that either part may be disconnected from
the other part and be moved to such a position as to cut the corresponding motor
out of circuit and at the same time prevent the movement of the first or main switch
beyond the positions corresponding to a series connection of the motors.
The chief feature of the present invention is as follows: The reversing handle
of the controller does not directly actuate the reversing switch but only operates
to alter the disposition of the parts connecting the two switches, after which the
first movement of the regulating handle actuates the reversing switch so as to
connect the motors for forward or backward movement of the car according to
the manner in which the reversing handle was first moved. When the regulating
or main operating switch is moved from its first power position to its first braking
position the second or the reversing switch is automatically actuated so that the
connections of the motors are reversed this being necessary to secure the braking
effect. When the main operating switch is moved from the first braking position
into the first power position the reversible switch is actuated in the opposite
direction so as to restore the motor connections to what they were originally.
Furthermore, the reversing handle of the controller is as usual capable of being
operated only when the regulating or main operating switch is in the zero position
and the motors disconnected from the power circuit, and the regulating handle can
only be moved after the reversing handle has been operated.

page_text: Means for practically carrying out the invention are illustrated in the accompanying
drawings,
Figure 1 being a front elevation of the controller the top portion of the cover
being in section the side cover being removed and the lower portion of the frame
being broken away.
Figure 2 is a front elevation on an enlarged scale of the upper portion of the
controller and the operating mechanism.
Figure 3 is a plan view of most of the mechanism shewn in Figure 2, the frame
and cover of the controller being shewn in section, and one side being broken
away.
Figure 4 is a plan view of mechanism for operating the reversing switch shewn in
one of its extreme positions, that is, in the first braking position.
Figure 5 is a view similar to Figure 4 shewing the controller in the first power
position, the reversing switch being set so that the circuits of the motors are reversed
with reference to the position shewn in Figure 4.
Figure 6 is a view, partially in plan and partially in section, of the controller
shewing details of the cut out switch.
Figure 7 is a detail view of a feature of the cut out device.
Figure 8 is a diagram of the controller and the motor and resistances in circuit
therewith, the surface of the main controller drum and that of each of the reversing
switch drums being shewn as developed in a plane.
Figure 9 is a diagram shewing the circuits of the motors and resistances
corresponding to the various power and brake positions of the controllers.
Referring now particularly to Figures 1 to 7 inclusive, 1 is the base or back portion
of the frame which is ordinarily fastened to the dash board of the vehicle, and 2 is a
cover through which project a shaft 3 that is coupled to and constitutes an extension
of the main controller drum shaft 3ª, and a shaft 4 that is in alignment with the
reversing switch shaft 4 but rotates independently thereof. The shaft 3 is
provided with the usual operating arm 5 and handle 6, and the shaft 4 with a
handle 7. The front sheet metal cover 8 may be of the usual construction and may
be hinged or otherwise fastened to the back or base portion 1. The main controller
drum 4b is provided with contact pieces 8 and 820, properly arranged to
co-operate with stationary contact fingers c to c16, as is usual in devices
of this character, so as to secure the desired changes in the circuit connections and
variations in resistance. The structure of these contact pieces and contact fingers is
not claimed by me as new, and the arrangement of the same will be more conveniently
described hereinafter in connection with Figures 8 and 9 of the drawings which shew
the circuits and circuit connections.
The abutting ends of shafts 3 and 3ª are fastened together by means of a
coupling 9-10 SO as to permit ready removal of the drum when desired.
The coupling 9-10 rotates in a bearing 11 and the upper portion of shaft 3 in
a bearing 12. Below this coupling 9-10 and bearing 11 the usual notched indicating
plate 13 is located, this plate being keyed to the shaft 3ª, or otherwise rigidly
fastened thereon and provided on its upper side with an annular rib 14, the latter
being cut away on one side to form a notch 15 the purpose of which will hereinafter
appear. The notched plate 13 is provided on its under side with a rib 16 which
extends throughout a portion of the circumference only. Below the rib 16 and between
that and the drum proper is a disc 17 of insulating material.
On the shaft 3 and between the bearings 11 and 12 are rigidly fastened two cam
plates 18 and 19.
Projecting from the bearing 11 is an extension 20, and projecting from the bear-
ing 12, in vertical alignment with the extension 20, is a similar extension 21.
The upper end of the shaft 4 is provided with a pinion 22, the pinion proper
being located just above the end of the shaft and being provided
with an integral extension in the form of a sleeve 22 which is fastened to
the shaft by means of a pin 23 and is supported in a bearing 24. The lower end of
the shaft 4 rests upon the top of the shaft 4*, the hollow pinion constituting a lateral

page_text: bearing therefor. Just above the pinion 22 the shaft 4 is turned down to form a
relatively small crank pin 25 which is surrounded by a rectangular block 26 having a
sufficiently loose fit thereon so that the pin may easily turn in the block. Fastened
to the shaft 4 just above the wrist. pin 25 and block 26 by means of a pin 27, or other-
wise, is a head 28 provided with projecting arms so constructed and arranged as to
form two deep notches 29 and 30 and an intermediate shallow notch 31. Just above
the head 28 a bearing 32 for shaft 4 is provided. An arm 33 is pivotally mounted at
its inner end near the back plate of the controller and is provided with a roller 33ª
at its outer end which is in position to engage at all times with one or other of the
notches 29, 30 and 31. Rigidly, connected with the arm 33 is an arm 34 which is
provided at its outer end with a lateral projection 35 of such form and dimensions as
to enter the recess 15 in the annular rib 14 when the roller 33" is in the middle
notch 31 of the head 28. A third arm 36, which is or may be a part of arm 34, is
provided at its outer end with a pin 37 which supports one end of a coiled spring 38.
The other end of the coiled spring 38 is provided with a hook 39 that engages with a
pin 40 on a holding pawl or lever 41, one end of this holding pawl or lever 41 being
sleeved or journalled upon the reversing switch drum shaft. 4 and the other end being
provided with a roller 42 which engages with the notches in the edge of the plate 13.
The arms 33, 34 and 36 preferably constitute parts of a single piece or casting
journalled at top and bottom upon suitable pins or studs, one of which is shewn at
43 in Figure 2.
Journalled in the extension brackets 20 and 21 by means of pintles 44* is a
head 44 having an upper arm or extension 45 in which is journalled a roller 46,
this roller being in the plane of the cam plate 18 on the shaft 3. The head 44 is
also provided with a lower arm 47 the outer end of which is provided with a
roller 48 in the plane of the cam plate 19 so as to engage with its cam surface.
Pivoted to the outer side of the head 44 is one end of an arm 49. This arm 49 is
broadened to form a head 50 having at its outer sides, near its outer end, down-
wardly projecting flanges 51, one of these flanges being provided with a rack 52 and
the other with a similar rack 53, these racks being constructed and arranged to
mesh with the teeth of the pinion 22, but being spaced apart such a distance that
when the pinion is in full engagement with one of the racks it is out of engagement.
with the other. The main or upper portion of the head 50 is provided with a long
slot 50 to receive the rectangular block 26, so that as the handle 7 is moved from
one position to another, the crank pin 25 will move the block 26 and thus shift the
racks 52 and 53 so as to bring the one or the other into engagement with the teeth
of the pinion 22. This block 26 also serves as a guide for the arm 49 and
head 50 as the same are reciprocated by the action of the cam plates 18 and 19
against the head or block 44.
The reversing switch comprises two drums 54 and 55, which are respectively
provided with the necessary contact strips p to p' and på to p15 to co-operate with
stationary contact fingers d to do and e to eas the drums are rotated to effect a
reversal of the armature circuits of the motors. Each of the drums 54 and 55 is
sleeved upon the shaft 4* and each is normally locked to the shaft by means of a
pin 56 which enters a suitable recess in the shaft and is held therein by means of a
spring 57, the outer end of the pin being provided with a ring 58 or other device
which may be readily grasped by the hand to withdraw the pin from its socket in the
shaft when it is desired to unlock the drum.
Rigidly fastened to the upper end of the drum 54 is a plate 59 having a peripheral
cam surface 59* at one side and a notch or socket 60 at the end of the cam surface.
The lower end of the drum 55 is provided with a plate 59 that is a duplicate of the
one at the top of the drum 54. Journalled in the frame 1, between the main drum
and reversing drums, is a long rod 61 to which are rigidly fastened two arms 62, the
upper arın 62 being in the same horizontal plane as the upper plate 59 and having
its rounded end held against the edge of the plate by a spring (not shewn). The
lower arm 62 is in the same horizontal plane as the lower plate 59. A third arm 63
is rigidly fastened at one end to the shaft or rod 61, the outer end of said arm being

page_text: provided with a hook 64 in the plane of the rib 16, this construction being such that
when it is desired to cut either motor out of circuit, the pin 56 of the corresponding
drum is withdrawn from its socket in the shaft 4 and the drum is turned to the
right until the outer end of the arm 62 corresponding to the plate 59 of that drum
drops into the socket 60. By reason of the cam surface 59 of this plate and the
distance of the socket 60 from the axis on which the drum turns, the arm 63 will be
moved inward towards the main controller drum a sufficient distance to bring the
hook 64 in the path of movement of the segmental rib 16 and thus prevent the
movement of the main drum beyond the last running position corresponding to
the connection of the motors in series when both motors are in circuit.
Referring now to Figures 8 and 9 of the drawings, M and M' are the motors, ƒ, ƒ¹³,
being the field magnets, and a, a¹, the armatures. r, 1, 2 and 3, are the resistances,
and c, c1, c2, c³, c4, cb, c, c7, c³, c³, c10, cll, c12, c13 and c¹ the contact fingers on one side
of the main drum, and c15, c16, the contact fingers on the other side of said drum. s is
the contact strip on the drum 4b corresponding to finger c; s¹ and 82, the strips
corresponding to finger c¹; s³ and s, the strips corresponding to finger c²; 86 and 6,
the strips corresponding to fingers 3 and c¹5; 87, the strip corresponding to finger c;
88, so and s10, the strips corresponding to finger c5; 811 and 12, the strips corres-
ponding to finger c; 13 and 14, the strips corresponding to finger c7; 815 and 816, the
strips corresponding to c; s17, 818 and 810, the strips corresponding to c; 20 and 821,
the strips corresponding to finger c¹0; 822 and 823, the strips corresponding to finger
cl; 8, the strips corresponding to finger c¹; 825, the strip corresponding to finger
c18; 826 and 827, the strips corresponding to fingers c14 and c¹6.
The several operative power positions of the controller drum and the notches in
the notched plate 13 corresponding thereto are designated by the numbers I, II, III,
IV, V, VI, VII, VIII, IX, and X, and the off position by O. The several braking
positions and the corresponding notches in the plate 13 are designated as A, B, C, D
and E. In Figure 8 these various notches in the plate 13 are indicated as in vertical
alignment with the corresponding spaces or positions on the drum. For convenience
of location of the holding pawl 41, these notches are not actually so located with
reference to the contact strips on the drum, but the operation is the same as it would
be if they were located as indicated in Figure 8.
It will be seen from the illustration in Figures 8 and 9, that in position I, the
motors are in series and that the portions 1, 2 and 3 of the resistance are in circuit.
In position II portion of the resistance is cut out, leaving the portions
2 and 3 of the resistance in circuit and the motors in series. In position III
portions and 72 of the resistance are cut out leaving portion in circuit
and the motors in series. In position IV all of the resistance is cut out, leaving the
motors in series. In position V portions 72, 73 of the resistance are again cut in and
the motors are in series. In position VI the same amount of resistance as in position
V is included in circuit and motor M' is cut out. In position VII the conditions are
the same as in position VI. In position VIII the same amount of resistance is in
circuit as in position VII and the motors are in parallel. In position IX portions 7+1
and 2 of the resistance are cut out, leaving the motors in parallel, and in position X
all of the resistance is cut out and the motors are in parallel, this being the last
running power position.
During the changes corresponding to positions I to X of the main drum, the contact
fingers d, d, d², e, e¹, and e² of the reversing switch are in position y and the fingers
ds, ds, da, e³ and et are in position y¹ or the first named set of fingers are in position z
and the second named set in position z¹. As the main drum passes to position A,
the sets of reversing switch fingers pass from positions y and y¹ to positions z aud z¹,
or vice versa, according to which positions they occupied during the power connection
of the motors.
In position A the motor connections are therefore reversed and the motors are
connected in parallel with all of the resistance in circuit, including the additional
resistance that was not used in any of the power positions. In position B the
connection is the same with one portion of the resistance cut out; in position C, the

page_text: same with another portion of the resistance cut out; in position D, the same with a
still further section of resistance cut out; and in position E, the same circuit.
connections with all resistance cut out.
Referring now to the figures of the drawings illustrating the mechanism of the
controller in connection with Figures 8 and 9, in each of Figures 1, 2, 3, and 6, the
main controller drum is shown in the O or off position, and the reversing switch
handle 7 is in its intermediate position, so that the roller 33ª on the arm 33 is in
the middle notch 31 of the head 28. By reason of this position of the parts, the
end 35 of arın 34 is located in the slot 15 in the annular rib 14, thus preventing any
movement of the controller drum in either direction. In order to operate the con-
troller the reversing switch handle 7 is moved either from left to right to bring the
roller 33 into notch 30 or from right to left to bring such roller into notch 29,
depending upon the direction in which it is desired to move the vehicle. In which-
ever direction the handle is moved, the notch receiving the roller 33" is of such depth
that the spring 38 will serve to withdraw the end 35 of arm 34 from the recess 15
and thus release the controller drum. It will also be seen that when the controller
drum is in this "off" or zero position, the pinion 22 is midway of the rack with which
it is in mesh and that the rollers 46 and 48 are respectively in engagement with
those portions of the peripheries of cam plates 18 and 19 that join the portions of
maximum and minimum radii. If the handle 7 of the reversing switch is moved
from left to right, the crank pin 25 acting upon the block 26 and the latter upon the
head 50 will serve to move the rack 52 into engagement with the pinion 22 and to
move the rack 53 completely out of engagement with such pinion. If the controller
drum handle be moved from the right to left, that is, in the direction of the arrow,
Figure 3, to bring the roller 42 on the pawl 41 into notch I, the cams 18 and 19
will be correspondingly moved so as to bring the roller 46 on arm 45 into engage-
ment with that portion of the periphery of the cam 18 having the greatest radius
and to bring the roller 48 on the arm 47 into contact with that portion of the
periphery of the cam plate 19 having the smallest radius. This action of the cam
plates upon the head 44 will move the head 50 and its racks 52 and 53 longitudinally
and thus serve by means of the engagement of the racks with the pinion 22 to
rotate the reversing switch drums so as to bring the contact fingers into positions y
and y. This position of the cam plates and the co-operating head 44 and its
rollers 46 and 48 is shewn in Figure 5. The illustration of the said figure is, how-
ever, different from that just described in that the position of the rack corresponds
to the extreme left-hand position of the reversing switch handle and the head 28,
thus ensuring the movement of the reversing switch drum in the opposite direction
to that described and therefore ensuring the reverse connection of the motors.
continued movement of the controller handle from right to left until position X is
reached, i.e., until the roller 42 rests in notch X, will effect the various changes
represented in the first ten positions indicated in Figure 9 of the drawings, and
no movement of the reversing switch will take place for the reasons that the portions
of the cam plates 18 and 19 having the respective maximum and minimum radii
remain in engagement with the rollers 46 and 48 on the arms 45, and 47 of the
head 44.
A
The notch X being the last running or operating notch corresponding to a maximum
speed of the motors; the handle of the controller will be moved in the opposite
direction, i.e., from left to right to decrease the speed of the motors or to bring them
to rest. The position of the reversing switch and its operating mechanism will
obviously remain unchanged until the notch I comes again into engagement with the
roller 42. In passing from notch I to notch O the parts will be moved into the
position shewn in Figure 3 except that one of the racks will be in mesh with
the pinion. Assuming that it is desired to secure the braking effect incident to
operating the motors as generators, the rotation of the drum will be continued from
left to right and when notch A comes into engagement with the roller 42, the action
of the cams upon the rollers 46 and 48 in the arins 45 and 47 will have shifted the
head 50 and its racks from right to left into the position shewn in Figure 4, thus

page_text: giving the necessary partial rotation to the reversing switch drums necessary to
bring the contact fingers into position z and z¹. The relation of the motors and
resistances is indicated at position A in Figure 9 of the drawings, this being the
position affording the minimum braking effect by reason of the fact that the maximum
amount of resistance is included in the circuit.
If the rotation of the drum be continued from left to right from notch to notch
until the notch E is reached, the various changes indicated in Figure 9 will be
effected, the final braking position E being that in which the motors are connected
in parallel in the local circuit as generators with no external resistance in such
circuit. When it is desired to again apply power to the car, the controller drum will,
of course, be rotated from right to left, and as the roller 42 passes from notch A to
notch T, the reversing switch will again be actuated by reason of the cam plates, the
racks and pinion and the intermediate mechanism. If it is desired to run the vehicle
in the opposite direction to that described, it is merely necessary to move the
reversing switch bandle 7 to bring the roller 33* into notch 29, thus moving the
rack 53 into full engagement with the pinion 22, as is indicated in Figure 5,
this change being necessarily made when the main drum is in the zero or
"off"
position, since the rib 14 on the notched plate 13 will prevent any movement of
the arms 33 and 34 and the head 28, when the drum is in any other position.
If one of the motors becomes disabled, or for any other reason it is desired to
cut either of the motors out of circuit, the pin 56 of the corresponding drum will
be withdrawn from its socket and the drum rotated from left to right so that
the respective sets of fingers will occupy positions x and x¹, this position of the
drum being reached when the notch 60 in the plate 59 is in position to receive
the end of arm 62. The rod 61 will be thus turned and will move the hook 64
of the arm 63 into position to be engaged by the end of rib 16 when the roller
reaches notch IV in the plate 13, it being obviously unnecessary and undesirable
to move the controller drum through the points corresponding to parallel con-
nection of the motors when there is only one motor in circuit.
I have not undertaken to illustrate and describe in detail the wiring of the con-
troller, although the same is shewn in part in Figure 1, since the invention is not
specially concerned with the wiring and anyone skilled in the art could make the
necessary connections and arrangements of circuits from the illustrations, and
description given.
While I have shewn and described specific mechanism for operating the controller
parts, in order that a full disclosure of means for practising the invention may be
inade, I do not regard the invention as limited to any specific details of construction,
the only requisite being that the mechanism employed shall be operative and capable
of effecting the desired functions.
Improvements in Controllers for Electric Motors.
I, REGINALD BELFIELD, of 32, Victoria Street, in the City of Westminster,
Electrician, 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 invention relates to controllers for electric motors, and particularly to that
class of controllers which embody means for controlling the power and speed of

page_text: motors employed for propelling railway vehicles, and also means for so arranging and
regulating the circuits of the motors that they may act as generators and thus
produce a braking effect such is necessary to reduce the speed of and bring to rest
the vehicle which is normally propelled by then when acting as motors.
According to the present invention the controller is constructed with two switches,
one of which is operated to vary the resistance in circuit with the motors and to
change the connection when the motors are supplied with electric current, the
positions of the switch under these conditions being conveniently designated
"power" positions; this main switch is furthermore arranged to connect the motors
in parallel in a closed local circuit and to vary the resistance in such circuit when
external sources of current have been cut off, the motors in such case acting as
generators and exerting a powerful braking effect, these latter positions of the switch
are called "braking" positions. The second of the two switches in the controller
consists of a two part reversing switch constructed so that either part may be dis-
connected from the other part and be moved to such a position as to cut the
corresponding motor out of circuit and at the same time prevent the movement of
the first or main switch beyond the position corresponding to a series connection
of the motors.
The chief feature of the present invention is as follows:-The reversing handle of
the controller does not directly actuate the reversing switch, but only operates to
alter the disposition of the parts connecting the two switches, after which the first
movement of the regulating handle actuates the reversing switch so as to connect
the motors for forward or backward movement of the car according to the manner in
which the reversing handle was first moved. When the regulating or main operating
switch is moved from its first power position to its first braking position the second
or the reversing switch is automatically actuated so that the connections of the
motors are reversed, this being necessary to secure the braking effect. When the
main operating switch is moved from the first braking position into the first power
position the reversing switch is actuated in the opposite direction so as to restore the
motor connections to what they were originally. Furthermore, the reversing handle
of the controller is as usual capable of being operated only when the regulating or
main operating switch is in the zero position and the motors disconnected from the
power circuit, and the regulating handle can only be moved after the reversing handle
has been operated.
Means for practically carrying out the invention are illustrated in the accompany-
ing drawings,
Figure 1 being a front elevation of the controller, the top portion of the cover
being in section, the side cover being removed, and the lower portion of the frame
being broken away.
Figure 2 is a front elevation on an enlarged scale of the upper portion of the
controller and the operating mechanism.
Figure 3 is a plan view of most of the mechanism shewn in Figure 2, the
frame and cover of the controller being shewn in section, and one side being broken
away.
Figure 4 is a plan view of mechanism for operating and reversing switch shewn in
one of its extreme positions, that is, in the first braking position.
Figure 5 is a view similar to Figure 4, shewing the controller in the first power
position, the reversing switch being set so that the circuits of the motors are reversed
with reference to the position shewn in Figure 4.
Figure 6 is a view, partially in plan and partially in section, of the controller shewing
details of the cut out switch.
Figure 7 is a detail view of a feature of the cut out device.
Figure 8 is a diagram of the controller and the motors and resistances in circuit.
therewith, the surface of the main controller drum and that of each of the reversing
switch drums being shewn as developed into a plane.
Figure 9 is a diagram shewing the circuits of the motors and resistances corre-
sponding to the various power and brake positions of the controllers.

page_text: Referring now particularly to Figures 1 to 7 inclusive, 1 is the base or back portion
of the frame which is ordinarily fastened to the dash board of the vehicle, and 2 is a
cover through which project a shaft 3 that is coupled to and constitutes an extension
of the main controller drum shaft 3*, and a shaft 4 that is in alignment with the
reversing switch shaft 4ª but rotates independently thereof. The shaft 3 is provided
with the usual operating arm 5 and handle 6, and the shaft 4 with a handle 7. The
front sheet metal cover 8 may be of the usual construction and may be hinged or
otherwise fastened to the back or base portion 1. The main controller drum 4b is
provided with contact pieces s to 828, properly arranged to co-operate with stationary
contact fingers c to c¹, as is usual in devices of this character, so as to secure the
desired changes in the circuit connections and variations in resistance. The structure
of these contact pieces and contact fingers is not claimed by me as new, and the
arrangement of the same will be more conveniently described hereinafter in con-
nection with Figures 8 and 9 of the drawings which show the circuits and circuit
connections.
The abutting ends of shafts 3 and 3" are fastened together by means of a
coupling 9-10 so as to permit ready removal of the drum when desired. The
coupling 9-10 rotates in a bearing 11 and the upper portion of shaft 3 in a bearing 12.
Below this coupling 9-10 and bearing 11 the usual notched indicating plate 13 is
located, this plate being keyed to the shaft 3, or otherwise rigidly fastened thereon
and provided on its upper side with an annular rib 14, the latter being cut away on
one side to form a notch 15, the purpose of which will hereinafter appear. The
notched plate 13 is provided on its under side with a rib 16 which extends throughout
a portion of the circumference only. Below the rib 16 and between that and the
drum proper is a disc 17 of insulating material.
On the shaft 3 and between the bearings 11 and 12 are rigidly fastened two cam
plates 18 and 19.
Projecting from the bearing 11 is an extension 20, and projecting from the
bearing 12, in vertical alignment with the extension 20, is a similar extension 21.
The upper end of the shaft 4 is provided with a pinion 22, the pinion proper being
located just above the end of the shaft, and being provided with an integral extension
in the form of a sleeve 22" which is fastened to the shaft by means of a pin 23 and
is supported in a bearing 24. The lower end of the shaft 4 rests upon the top of the
shaft 4, the hollow pinion constituting a lateral bearing therefor. Just above the
pinion 22 the shaft 4 is turned down to form a relatively small crank pin 25 which is
surrounded by a rectangular block 26 having a sufficiently loose fit thereon so that
the pin may easily turn in the block. Fastened to the shaft 4 just above the wrist
pin 25 and block 26 by means of a pin 27, or otherwise, is a head 28 provided with
projecting arms so constructed and arranged as to forin two deep notches 29 and 30
and an intermediate shallow notch 31. Just above the head 28 a bearing 32 for
shaft 4 is provided. An arm 33 is pivotally mounted at its inner end near the back
plate of the controller and is provided with a rollor 33ª at its outer end which is in
position to engage at all times with one or other of the notches 29, 30 and 31.
Rigidly connected with the arm 33 is an arın 34 which is provided at its outer end
with a lateral projection 35 of such form and dimensions as to enter the recess 15 in
the annular rib 14 when the roller 33* is in the middle notch 31 of the head 28. A
third arm 36, which is or may be a part of arm 34, is provided at its outer end with
a pin 37 which supports one end of a coiled spring 38. The other end of the coiled
spring 38 is provided with a hook 39 that engages with a pin 40 on a holding pawl
or lever 41, one end of this holding pawl or lever 41 being sleeved or journalled upon
the reversing switch drum shaft 4 and the other end being provided with a roller 42
which engages with the notches in the edge of the plate 13.
The arms 33, 34 and 36 preferably constitute parts of a single piece or casting
journalled at top and bottom upon suitable pins or studs, one of which is shown at 43
in Figure 2.
Journalled in the extension brackets 20 and 21 by means of pintles 44 is a
head 44 having an upper arm or extension 45 in which is journalled a roller 46, this

page_text: roller being in the plane of the cam plate 18 on the shaft 3. The head 44 is also
provided with a lower arm 47 the outer end of which is provided with a roller 48 in
the plane of the cam plate 19 so as to engage with its cam surface. Pivoted to the
outer side of the head 44 is one end of an arm 49. This arm 49 is broadened to
form a head 50, having at its outer sides, near its outer end, downwardly projecting
flanges 51, one of these flanges being provided with a rack 52, and
the other with a similar rack 53, these racks being constructed and
arranged to mesh with the teeth of the pinion 22, but being spaced apart such a
distance that when the pinion is in full engagement with one of the racks it is out
of engagement with the other. The main or upper portion of the head 50 is
provided with a long slot 50 to receive the rectangular block 26, so that as the
handle 7 is moved from one position to another, the crank pin 25 will move the
block 26, and thus shift the racks 52 and 53 so as to bring the one or the other into
engagement with the teeth of the pinion 22. This block 26 also serves as a guide
for the arm 49 and head 50 as the same are reciprocated by the action of the cam
plates 18 and 19 against the head or block 44.
The reversing switch comprises two drums 54 and 55, which are respectively
provided with the necessary contact strips p to p', and ps to p, to co-operate with
stationary contact fingers d to d³, and e to e¹, as the drums are rotated to effect a
reversal of the armature circuits of the motors. Each of the drums 54 and 55 is
sleeved upon the shaft 4", and each is normally locked to the shaft by means of a
pin 56 which enters a suitable recess in the shaft and is held therein by means of a
spring 57, the outer end of the pin being provided with a ring 58 or other device
which may be readily grasped by the hand to withdraw the pin from its socket in the
shaft when it is desired to unlock the drum.
Rigidly fastened to the upper end of the drum 54 is a plate 59 having a peripheral
cam surface 59 at one side and a notch or socket 60 at the end of the cain surface.
The lower end of the drum 55 is provided with a plate 59 that is a duplicate of the
one at the top of the drum 54. Journalled in the frame 1, between the main drum and
reversing drums is a long rod 61 to which are rigidly fastened two arms 62, the
upper arm 62 being in the same horizontal plane as the upper plate 59 and having
its rounded end held against the edge of the plate by a spring
(not shewn). The lower arm 62 is in the same horizontal plane as
the lower plate 59. A third arm 63 is rigidly fastened at one
end to the shaft or rod 61, the outer end of said arm being provided with a
hook 64 in the plane of the rib 16, this construction being such that when it
is desired to cut either motor out of circuit, the pin 56 of the corresponding drum is
withdrawn from its socket in the shaft 4" and the drum is turned to the right until
the outer end of the arm 62 corresponding to the plate 59 of that drum drops into
the socket 60. By reason of the can surface 59 of this plate and the distance of the
socket 60 from the axis on which the drum turns, the arın 63 will be moved inward
towards the main controller drum a sufficient distance to bring the hook 64 in the
path of movement of the segmental rib 16 and thus prevent the movement of the
main drum beyond the last running position corresponding, to the connection of
the motors in series when both motors are in circuit.
Referring now to Figures 8 and 9 of the drawings, M and M are the motors, f, f¹;
being the field magnets and a, a, the armatures. ,, and are the resistances,
and c, c', c², c³, c², c³, c", c², c³, c", clo, cli, c¹², c¹³, and c¹ the contact fingers on one
side of the main drum, and e¹³ c, the contact fingers on the other side of said drum.
* is the contact strip on the drum 4h corresponding to finger c, which is connected to
the trolley or current supply wire; 81 and 2, the strips corresponding to finger c¹;
83 and 4, the strips corresponding to finger c²; s and 86, the strips corresponding to
fingers and c; 87, the strip corresponding to finger c; 88, 89 and 10, the strips
corresponding to finger c; 8¹¹ and 12, the strips corresponding to finger c; 13 and 81+,
the strips corresponding to finger c; 85 and 810, the strips corresponding to finger cs;
81, 819 and 8, the strips corresponding to cº; 8 and 82, the strips corresponding to
B

page_text: finger c¹0 22 and 8, the strips corresponding to finger cll; 824, the strip corresponding
to finger c¹; 825, the strip corresponding to finger c¹³ which is connected to earth E;
826 and 27, the strips corresponding to fingers c¹¹ and c¹6.
The several operating power positions of the controller drum and the notches in
the notched plate 13 corresponding thereto are designated by the numbers I, II, III,
1V, VIII, IX, and X, and the off position by O. Between the positions IV. and
VIII. there are other positions, which are designated in Figures 8 and 9 by the
lines marked V, VI, VII, these are not operative positions of the controller, but
are merely positions in which preparation is made for joining the motors in
parallel by re-inserting the resistance and braking the circuit of the motor;
consequently there are no notches provided on the plate 13 corresponding to these
positions since the controller drum is not intended to be kept in any of the three
for any length of time. The several braking positions and the corresponding
notches in the plate 13 are designated as A, B, C, D and E. In Figure 8 these
various notches in the plate 13 are indicated as in vertical alignment with the
corresponding spaces or positions on the drum. For convenience of location of
the holding pawl 41, these notches are not actually so located with reference to
the contact strips on the drum, but the operation is the same as it would be if they
were located as indicated in Figure 8.
It will be seen from the illustration in Figures 8 and 9 that in position 1, the
current enters at the contact finger c, which is in contact with the strip s, and from
thence passes to the strip 85 to the contact finger c³ in contact therewith, thence
through the resistance 71, 72, 73 to the contact finger c¹ and thence to the fixed contact
finger of the reversing switch.
If we assume that the contact fingers d, d¹, d², e, e¹ e are in the position y, and the
fingers d³, d, d, and are in the position y¹, the current will pass from the
contact, through the strip to the contact d through the armature a of the first
motor to the finger d²; which is in contact with the strip p, from the strip p' the
current passes to the strip p and thence to the finger 3, through the field magnet
coil to the finger d³, through the strip p to the finger d to the contact finger c¹¹ to
the strip 22, strip 20, finger clo, finger es, strips, strip s", finger c', the finger c³,
the strip s8, the strip s", the finger cand from thence to the finger c¹ of the reversing
switch; from the finger e¹ through the strip p¹³, the finger e, the armature a¹ of the
second motor, the finger e², the strip pls, the strip 2, the finger e³, the field magnet
coil of the second motor to the contact finger c¹³; from the contact finger c¹³
the current passes to the other supply main. Hence in this position the motors
are in series and the portions 21, 22, 2, of the resistances are in circuit. In position II.
portion of the resistance is cut out, leaving the portions 72 and 3 of the resistance
in circuit and the motors in series. In position III. portions 1 and 2 of the
resistance are cut out, leaving portion 3 in circuit and the notors in series. In
position IV. all of the resistance is cut out, leaving the motors in series. In
position V. portions 72, 7 of the resistance are again cut in and the motors are
in series. In position VI. the same amount of resistance as in position V. is included
in circuit and motor M¹ is cut out. In position VII. the conditions are the same as
in position VI. In position: VIII. the same amount of resistance is in circuit as in
position VII. and the motors are in parallel. In position IX. portions 1 and 2 of the
resistance are cut out, leaving the motors in parallel, and in position X. all of the
resistance is cut out and the motors are in parallel, this being the last running power
position.
During the changes corresponding to positions I. to X. of the main drum, the
contact fingers d, d', d², e, e¹ and e² of the reversing switch are in position y and
the fingers d, d, da, es and et are in position or the first named set of fingers are
in position and the second named set in position ¹. As the main drum passes
to position A, the sets of reversing switch fingers pass from positions and y¹ to
positions and 21, or vice versa, according to which positions they occupied during
the power connection of the motors.

page_text: In position A the motor connections are therefore reversed and the motors are
connected in parallel with all of the resistance in circuit, including the additional
resistance that was not used in any of the power positions. The circuits will be
as follows:-
Beginning at the armature a of the first motor the current will pass to finger d,
the contact stripp, the contact strip p, the finger 3, the field magnet f, the finger,
the contact strip p, the finger d' to the finger on the main drum. From the
other end of the armature & the circuit is through the finger d², the contact strip p*,
the finger.d, the finger c¹, the resistances 23, r², and to the finger c15, the contact
strips, the contact strip 8, the contact strip 10, the finger c³, the finger c, the
contact strips, the contact strip 81, the finger c³, the finger co, the contact strip 821,
the contact strip 23, the finger c¹ to the finger c¹², and from thence in the manner before
mentioned to the armature & again. From the armature ¹ of the second motor the
current will pass in one direction to the finger c, the contact strip the contact
strip ps, the finger e, the field magnet coil 1, the finger c¹³, the strip 25, the strip 24
to the finger c¹³. In the other direction the current passes to the finger e, the
strip p, the finger el, the finger ca, the strip 8, the strip 8 to the finger c
at the beginning of the resistance 23. There will also be a connection between
the finger c and the finger c¹ through the strips 82, 82, that is to say, the point of
junction of the armature a and its field magnet coil will be joined to the point of
junction of the armature coil a¹ and its field magnet coil f; in position B the con-
nection is the same with one portion of the resistance cut out; in position C, the
same with another portion of the resistance cut out; in position D, the same with a
still further section of resistance cut out, and in position E, the same circuit connec-
tions with all resistance cut out.
Referring now to the figures of the drawings illustrating the mechanism of the
controller in connection with Figures 8 and 9, in each of Figures 1, 2, 3 and 6, the
main controller drum is shewn in the 0 or off position, and the reversing switch
handle 7 is in its intermediate position, so that the roller 33" on the arm 33 is in the
middle notch 31 of the head 28. By reason of this position of the parts, the end 35
of arm 34 is located in the slot 15 in the annular rib 14, thus preventing any move-
ment of the controller drnm in either direction. In order to operate the controller
the reversing switch handle 7 is moved either from left to right to bring the roller 33*
into notch 30 or from right to left to bring such roller into notch 29, depending upon
the direction in which it is desired to move the vehicle. In whichever direction the
handle is moved, the notch receiving the roller 33ª is of such depth that the spring 38
will serve to withdraw the end 35 of arm 34 from the recess 15 and thus release
the controller drum. It will also be seen that when the controller drum is in
this "off" or zero position, the pinion 22 is midway of the rack with which it is in
mesh, and that the rollers 46 and 48 are respectively in engagement with those
portions of the peripheries of cam plates 18 and 19 that join the portions of maximum
and minimum radii. If the handle 7 of the reversing switch is moved from left to
right, the crank pin 25 acting upon the block 26 and the latter upon the bead 50
will serve to move the rack 52 into engagement with the pinion 22 and to move the
rack 53 completely out of engagement with such pinion. If the controller drum
handle be moved from the right to left, that is, in the direction of the arrow, Figure 3,
to bring the roller 42 on the pawl 41 into notch I, the cams 18 and 19 will be cor-
respondingly moved so as to bring the roller 46 on arın 45 into engagement with that
portion of the periphery of the cam 18 having the greatest radius and to bring the
roller 48 on the arm 47 into contact with that portion of the periphery of the
cain plate 19 having the smallest radius. This action of the can plates upon
the head 44 will move the head 50 and its racks 52 and 53 longitudinally and
thus serve by means of the engagement of the racks with the pinion 22 to rotate the
reversing switch drums so as to bring the contact fingers into positions y and y¹.
This position of the cam plates and the co-operating head 44 and its rollers 46 and 48
is shewn in Figure 5. The illustration of the said figure is, however, different from
that just described in that the position of the rack corresponds to the extreme left-

page_text: hand position of the reversing switch handle and the head 28, thus ensuring the
movement of the reversing switch drum in the opposite direction to that described
and therefore ensuring the reverse connection of the notors. A continued movement
of the controller handle from right to left until position X is reached, i.e., until the
roller 42 rests in notch X, will effect the various changes represented in the first ten
positions indicated in Figure 9 of the drawings, and no movement of the reversing
switch will take place for the reason that the portions of the cam plates 18 and 19
having the respective maximum and minimum radii remain in engagement with
the rollers 46 and 48 on the arms 45 and 47 of the head 44.
The notch X being the last running or operating notch corresponding to a
maximum speed of the motors, the handle of the controller will be moved in the
opposite direction, i.e., from left to right to decrease the speed of the motors or to
bring them to rest. The position of the reversing switch and its operating mechanism
will obviously remain unchanged until the notch I comes again into engagement with
the roller 42. In passing from notch I to notch the parts will be moved into the
position shewn in Figure 3 except that one of the racks will be in mesh with the
pinion. Assuming that it is desired to secure the braking effect incident to operating
the motors as generators, the rotation of the drum will be continued from left to right
and when notch A comes into engagement with the roller 42, the action of the
cams upon the rollers 46 and 48 in the arms 45 and 47 will have shifted the
head 50 and its racks from right to left into the position shewn in Figure 4,
thus giving the necessary partial rotation to the reversing switch drums necessary
to bring the contact fingers into position and 21. The relation of the motors
and resistances is indicated at position A in Figure 9 of the drawings, this being the
position affording the minimum braking effect by reason of the fact that the maximum
amount of resistance is included in the circuit. If the rotation of the drum be
continued from left to right from notch to notch until the notch E is reached, the
various changes indicated in Figure 9 will be effected, the final braking position E
being that in which the motors are connected in parallel in the local circuit as
generators with no external resistance in such circuit. When it is desired to again
apply power to the car, the controller drum will, of course, be rotated from right to
left, and as the roller 42 passes from notch A to notch I the reversing switch will
again be actuated by reason of the cam plates, the racks and pinion and the inter-
mediate mechanism. If it is desired to run the vehicle in the opposite direction to
that described, it is merely necessary to move the reversing switch handle 7 to bring
the roller 33ª into notch 29, thus moving the rack 53 into full engagement with the
pinion 22, as is indicated in Figure 5, this change being necessarily made when the
main drum is in the zero or "off" position, since the rib 14 on the notched plate 13
will prevent any movement of the arms 33 and 34, and the head 28, when the drum
is in any other position. If one of the motors becomes disabled, or for any other
reason it is desired to cut either of the motors out or circuit, the pin 56 of the
corresponding drum will be withdrawn from its socket and the drum rotated from left
to right so that the respective sets of fingers will occupy positions and x, this
position of the drum being reached when the notch 60 in the plate 59 is in position
to receive the end of arm 62. The rod 61 will be thus turned and will move the
hook 64 of the arın 63 into position to be engaged by the end of rib 16 when the
roller reaches notch IV in the plate 13, it being obviously unnecessary and undesirable
to move the controller drum through the points corresponding to parallel connection
of the motors when there is only one motor in circuit.
I have not undertaken to illustrate and describe in detail the wiring of the
controller, although the same is shewn in part in Figure 1, since the invention is not
specially concerned with the wiring and anyone skilled in the art could make the
necessary connections and arrangements of circuits from the illustrations and
description given.
While I have shewn and described specific mechanism for operating the controller
parts, in order that a full disclosure of means for practising the invention may be
inade, I do not regard the invention as limited to any specific details of construction,

page_text: the only requisite being that the mechanism employed shall be operative and capable
of effecting the desired functions.
Having now particularly described and ascertained the nature of iny said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. A series-parallel controller in which the reversing handle does not directly
actuate the reversing switch, but determines the position of the parts so that when
the controlling and regulating switch handle is moved the reversing switch is
automatically actuated to connect the motors in the desired manner.
2. A controller of the class described and having a main regulating switch and a
reversing switch for governing the direction of movement of the car, the two switches
being so connected that when the main switch is moved from a position in which
current is supplied to the motors to one in which the motors act as generators the
reversing switch is automatically operated to reverse the motor connections and
vice versa.
3. In a controller of the class described the devices for automatically actuating the
reversing switch constructed and operating substantially as described with reference
to Figures 2, 3, 4 and 5 of the accompanying drawings.
4. In a series parallel controller a two-part reversing switch one part corresponding
to each motor and either part capable of being disconnected from the switch shaft
and rotated so as to cut its corresponding motor out of circuit.
5. The devices for limiting the movement of the main switch when one of the
motors is cut out, constructed and operating substantially as described with reference
to Figures 3, 6 and 7 of the drawings.
6. Controllers constructed and operating substantially as described with reference to
the accompanying drawings.
W. P. THOMPSON & Co.,
322, High Holborn, London, W.C., Patent Agents for the Applicant.