Improvements in Controlling-apparatus for Electro-motors.
Year: 1894

page_text: Date of Application, 30th July, 1894-Accepted, 8th Sept., 1894
COMPLETE SPECIFICATION.
Improvements in Controlling-apparatus for Electro-motors.
We, JEAN BAPTISTE GUSTAVE ADOLPHE CANET, of 3 Rue Vignon, Paris, in
the Republic of France, and ANDRÉ HILLAIRET of 22 Rue Vicq d'Azir, Paris,
aforesaid, Engineers, do hereby declare the nature of this invention and in what
manner the same is to be performed to be particularly described and ascertained
in and by the following statement :-
This invention relates to means for controlling the working of electro-motors
used for operating bodies or machines such as elevators, winches, travelling bridges,
ships' and other turrets, and tramway and railway vehicles, the movements of which
are limited in extent and require to be reversed from time to time.
In such cases it is desirable, both as regards safety and in order to prevent
damage to the stops used to limit the movement of the aforesaid bodies or
machines, that the electro-motor operating the same shall be stopped automatically
when the body or machine arrived at the said stops, and this invention relates
to means whereby this result can be effected in a simple, convenient and effective
manner.
In the accompanying drawings,
Figs. 1 to 5 inclusive illustrate one construction of apparatus according to our
invention,
Fig. 1 being a central vertical section partly in elevation ;
Fig. 2 a horizontal section on the line II II of Fig. 1 ;
Fig. 3 a section on the line III III of Fig. 1;
Fig. 4 a section on the line IV IV of Fig. 1; and
Fig. 5 a diagram showing the electrical connections of the apparatus.
Figs. 6 and 7 illustrate a modified construction,
Fig. 6 being a similar view to Fig. 1, and
Fig. 7 a diagram showing the electrical connections.
Figs. 8 to 18 inclusive, illustrate further modifications hereinafter more fully
explained.
Referring to Figs. 1 to 5 inclusive, the controlling apparatus comprises the
following parts: An operating shaft 1 on the upper end of which is a handle 2
capable of being moved to the right and to the left over a fixed arc 3; a switch
for electrically connecting the stops as required (hereinafter called the stop-
switch); a switch for reversing the direction of motion of the electro-motor and
hereinafter called the reversing-switch; transmitting-sectors; an intermediate
horizontal shaft; a double electro magnetic clutch comprising two sleeves loose
on the intermediate shaft and carrying two electro-magnets, a movable double
armature keyed on the shaft, and coupling sectors fixed on the sleeves; a shaft on
which is mounted a brush carrier and which is provided with a bevel-pinion
constantly in gear with the coupling-sectors; the brush-carrier proper or operating
arm carrying the brushes and the short-circuiting contact-pieces; a spring for
returning the brushes and their connection to their normal positions; a com-
mutator i and a rheostat composed of flat coils of copper wire placed one above
the other.
The casing of the apparatus which is of conducting material, is constructed of
three cast-iron standards 4, which are suitably stayed together, are fixed at their
lower ends to a cast-iron base-plate 5, and carry at their upper ends a cover 6.
This cover, through which extends the operating-shaft 1, is provided with two
sight-holes 7 closed by screw-plugs 8. To the standards 4 three bent metal sheets 9

page_text: are secured by a row of screws or by other suitable means, so as to form a cylindrical
casing. One of these sheets is made semi-cylindrical so as to allow of the removal
of the coils of the rheostat in case of damage without its being necessary to remove
the upper parts of the apparatus.
The operating-shaft 1 ends in a squared portion on which the handle 2 is
fitted. The shaft 1 is guided partly by the cover 6 and partly by a collar
In order to
(not shown) carrying an arc 3 over which the handle 2 moves.
regulate its movement, the handle 2 carries a pin or projection 10 which is forced
by a helical spring 11 to enter notches 12 in the arc 3. The object of these
notches is to enable the handle to be kept at a zero-mark, and also to cause the
handle, when operated, to make a short stoppage when the pin or projection 10
ineets the left hand and right hand stops, that is to say, at the precise moment
when the armature comes into contact with the sleeve of the electro magnetic
clutch.
The stop-switch is an ordinary switch consisting of four fixed contact-
pieces 15, 16, 17, and 18 (Fig. 2) mounted on a base-piece 13 of insulating
material such as marble and of a movable contact 14 keyed or otherwise secured
on the operating shaft 1. The contact-piece 15 is in constant electrical connection
with the entering terminal of a shunt circuit from the main circuit, and is of such
an extent as to remain always in contact with the movable contact 14 during the
whole range of its movement. The contact-piece 18 is arranged diametrically
opposite to the contact-piece 15 and is a neutral or dummy contact-piece for
enabling the shunt circuit to be broken when the operating handle 2 is at zero.
The contact-pieces 16 and 17 which are arranged on the right and left of the
neutral contact piece, are connected respectively to the right-hand stop 16ª (Fig. 5)
through the electro-magnet 31 of the double acting clutch and to the left-hand
stop 17 (Fig. 5) through the other electro-magnet 32 of the said clutch. This
arrangement enables a portion of the main current to be sent into the stop and the
coupling sleeve on that side to which the handle 2 is moving, and thus to effect
the movement of the part to be operated, as will be hereinafter more fully
described.
The reversing-switch is similar to the stop-switch and is located immediately
under the latter. It consists (Fig. 5) of a movable contact 19 keyed on the
operating-shaft 1 and of six fixed contact-pieces 20, 21, 22, 23, 24 and 25. Two
of the fixed contact-pieces, namely 20 and 21 are in constant electrical connection
with the entering terminals of the generator-circuit; two, namely 23 and 24 are
electrically connected to the brushes of the electro-motor M (Fig. 5), one of
them 23 through the commutator and the rheostat ; and the remaining two, namely
22 and 25, are unconnected and constitute neutral or dummy contacts corre-
sponding to the zero position of the handle 2. Whatever may be the position
of the movable contact 19, it is always in contact with the two second mentioned
contact-pieces 23 and 24, and as it moves either to the right hand or to the left
it connects them alternately with one or the other brush of the motor M. In
this manner the circuit is always broken at the zero position of the handle 2,
and the entering terminal of the current for the electro-motor M is reversed
according to the direction of movement of the movable contact 19.
The transmitting-sectors 26 and 27 are formed of two portions of gun-metal
bevel wheels. One sector 26 is keyed on the vertical operating-shaft 1; and the
other 27 is keyed on the horizontal intermediate shaft 28. The shaft is thus
directly operated by the movement of the lever 2.
The horizontal intermediate shaft 28 is carried in two bearings 29 and 30, fixed
to two of the standards 4. On the shaft 28 there are arranged, in addition to the
transmitting-sector 27, the two electro-magnets 31 and 32 and the double
armature 33, 34 of the double acting magnetic clutch.
The magnetic clutch comprises the two electro-magnets 31 and 32 which corre
spond to the two directions of rotation of the electro-motor M and are enclosed in
cylindrical casings 31* 32* mounted loosely on the shaft 28. The coils of these

page_text: electro magnets are contained in an annular space situate between the core proper
and the casing 31* or 32* which with the corresponding armature, closes the
magnetic circuit of the electro-magnet. The circuits of the electro-magnets
comprise the stops 16 and 17" and the stop-switch and constitutes a shant from the
main circuit. To each of the casings 31* 32* there is fixed a gun-metal bevel
coupling-sector 35 or 36 respectively. Between the two electro magnets 31 and 32
there is situated the movable double armature 33, 34, which is formed in one with
a sleeve 37 keyed on the horizontal intermediate shaft 28.
Each of the discs 33
and 34 forming an armature, is provided with a tooth 38 (Fig. 4) which at the
outset of the operation, engages in a recess 39 formed in the casing of the corre-
sponding electro magnet 31 or 32 and serves to ensure the operation of the said
electro magnet, and consequently of its coupling-sector 35 or 36. The distance
existing between the tooth and its bearing in the recess at the position of zero, is
such as to permit of the establishment of the magnetic field before the stop engages
in the recess.
The brush-carrying shaft 40 is non-rotatable and is fixed with its axis in line
with that of the vertical operating-shaft 1. A gun-metal sleeve 41 is mounted
loosely on the shaft 40 and carries an operating arm 42. The end of the sleeve 41
is provided with teeth so as to form a bevel pinion gearing with both of the
coupling-sectors 35 and 36.
The brush-carrier consists of an operating-arm 42 on one end of which is mounted
a holder 44 carrying brushes that are constantly in contact with the periphery of
the commutator-like collector 43. The arm 42 carries also a contact-piece 45,
which short-circuits the induction coils of the electro-motor M when the handle 2
is brought back to zero. The short-circuiting is effected by means of two suitably
arranged rubbing-contacts 46 and 47 each of which is electrically connected to one
terminal of the electro-motor M, and both of which are electrically connected by
the contact-piece 45 at the zero position of the handle 2. The returning-spring 48
is a spiral spring, one of the ends of which is attached to the non-rotatable shaft 40
by means of a ring 49, whilst the other end is attached to the brush-carrier 42.
The object of the spring 48 is to bring the brushes back to the neutral contact
piece of the commutator when the circuit of the magnetic coupling is automatically
broken by the action on one of the stops 16 and 17ª of the part operated by the
electro-motor M.
The collector 43 is constructed similarly to the commutator of a dynamo; and its
contact-pieces are connected to the several coils constituting the resistances 50 of the
rheostat. In the middle is the neutral contact-piece which is separated from the
others by insulating material.
The resistances 50 are placed at the lower part of the casing of the apparatus and
are formed of a series of flat coils of copper wire placed one above another. The
entering and exit wires of these coils are connected to the contact-pieces of the
commutator, by means of which they are coupled up in series. The successive coils
constituting the resistances are separated by discs 51 of insulating material for
example wood.
The operation of the apparatus is as follows :-
At
When current is sent into the motor from the delivering switch-board of the
generating dynamos, and the handle 2 is in its zero position, there is, on account of
the arrangement of the apparatus, no circuit made. By moving the handle 2 in
one or the other direction, the vertical shaft 1 is caused to operate the movable
part 14 of the stop-switch in such a manner as to send the current into the electro-
magnet of the magnetic clutch that corresponds to the direction of the motion.
the same time the movable contact-piece of the reversing-switch moves in such a
manner as to send the current into the motor in the direction desired. By
continuing to move the lever 2, the horizontal intermediate shaft 28 is caused
to rotate, by means of the transmitting sectors 26 and 27; and the movable
armature 33 and 34 becoming attracted on account of the passage of the current
through say the electro-magnet 31 corresponding to the position of the lever 2, the

page_text: said magnet and its casing are compelled to move towards the armature 33, 34 so that
the tooth 38 is caused to engage in the recess 39 formed in the said casing. The
lever 2 now rotates the coupling-sector 35 and consequently the pinion 41 fixed on
the brush-carrier 42. The brush-carrier is thus moved and the brushes leave the
neutral contact-piece and come into contact with the active contact-pieces of
the collector 43. The short-circuiting now ceases and current is sent into the
electro-motor M at a low potential through the rheostat. This potential increases
with the movement of the lever 2 until the brush arrives at the contact-piece which
corresponds with the force required for starting. At this moment the electro-
motor M starts and its velocity of rotation will go on increasing until the lever 2 has
arrived at the limit corresponding to the maximum velocity. To each position of
the lever 2 there corresponds a definite velocity, so that by the arrangement
described, the velocity of the electro-motor can be made to assume various values
between the maximum and minimum limits. When the lever 2 is moved back to
zero in order to stop the electro-motor, the motor has its current cut off and becomes
short-circuited, which ensures its instantaneous stoppage. If, when the motor
has been started with a certain velocity, the lever 2 be let go in the position
corresponding to that speed, the stop 16 or 17b (Fig. 5) on the body or machine
operated by the electro-motor M will act at the limits of the travel, upon the
electric contact stops 16 or 17ª respectively and the current will be cut off
automatically from the electro-magnet 31 or 32, whereupon the corresponding
electro-magnet will be moved away from the armature 33, 34 by a helical
spring 28. At the same time, the electro-motor will be short-circuited and stop
instantaneously.
Figs. 6 and 7 illustrate a modification of the herein before described apparatus
which differ from the latter in that the connection between the operating shaft 1 and
brush-carrier 42 is effected by a single magnetic clutch 31 acting continuously
instead of by two clutches alternately in gear, with their circuits broken every time
the handle 2 moves into the zero position. The general arrangement of the casing
is unaltered. Also, the reversing-switch, the brush carrier, the commutator, and
the rheostat, do not differ in any way from those hereinbefore described. The
modifications relate only to the stop-switch, the transmitting-sectors, the intermediate
shaft, and the magnetic clutch.. The stop-switch is an ordinary switch provided
with three fixed contact-pieces 52, 53 and 54, (Fig. 7) mounted on a marble or
other insulating base, with a movable contact 14 keyed or otherwise suitably fixed
on the operating-shaft 1. The contact-piece 52 is in constant electrical connection
with the entering terminal of a shunt circuit from the main circuit and is of
sufficient extent to remain always in contact with the movable contact 14 over the
entire range of movement of the said movable contact. The fixed contact-
pieces 53 and 54 are arranged symmetrically to each other with regard to the zero
position of the movable contact 14, and correspond to the range of movement of
the handle 2 in its two directions of movement. Their two ends remote from the
contact-piece 52 are sufficiently near to be electrically connected by the movable
part 14 when the latter is at zero. Each of the contact-pieces 53 and 54 is
connected with the circuit of one of the electrical stops 16 and 17" in such
a manner that the return portion of the circuit of the clutch is formed through both
of the electrical stops at the same time when the handle 2 is in the zero-position
and by one stop only, namely the one corresponding to the direction of the
movement, when the movable contact 14 is turned. This arranged, the stop-switch
never breaks the circuit of the electro-magnetic clutch, and consequently can never,
in any position whatever, cause the slightest sparking.
The transmitting-sectors 26 and 27 are formed by two portions of gun-metal
bevel-wheels, one 26 of which is keyed on the vertical operating shaft, and the
other 27 is fixed by screws on the casing of the electro-magnet 31.
The intermediate horizontal shaft 28 is carried in two bearings 29 and 30 fixed to
the standards 4 of the casing. On the shaft 28 are loosely mounted the electro-
magnet 31, its armature 34, and the two coupling sectors 35 and 36.

page_text: The magnetic clutch, which serves to couple the operating-shaft 1 to the brush-
carrier 42. comprises the electro-magnet 31 mounted loosely on the shaft 28. The
coils of this electro-magnet are contained in an annular space situate between the
core proper and the outer portion of the shell and casing as and for the purpose
hereinbefore described with reference to the arrangement shown in Figs. 1 to 5
inclusive. The circuit of the electro-magnet is a shunt from the main circuit, and
connects the stops 16 and 17ª in parallel when the switch for the stops is in the
zero-position. In front of the magnet core and also mounted loosely on the
intermediate shaft 28 is the armature 34 of the electro-magnet 31. This armature 34
carries parallel to the shaft 28, a pin 56 which is embraced with a slight amount of
play at each side by two tail-pieces 57 & 58 on the two coupling sectors 35 & 36.
These sectors are loose on the shaft 28 and constantly engage in the coupling
pinion 41 in such a manner that when the apparatus is in operation only one sector
is transmitting motion at any time. The other sector is moved in the opposite
direction by the pinion 41 without actuating any mechanism, and is brought back
into its initial or zero position when the operating-handle 2 is returned to zero.
The two sectors 35 and 36, are always symmetrically situated with
vertical plane containing their axis, in whatever position the handle 2
armature 34 carries on its flat surface, a tooth adapted to engage in a i,
in the shell or casing of the magnet 31 in the manner described with re
the construction shown in Figs. 1 to 4.
ard to a
The
.
"med
to
In the zero position the armature is kept away from the shell by a heal
spring 28, so that the aforesaid tooth is not engaged in its recess and the armature 34
is independent of the shell or casing of the magnet 31.
In this modified arrangement, when the current is turned on to the electro-motor
by means of the switch-board of the generating dynamo and the lever 2 is in its
zero position, then in consequence of the arrangements hereinbefore described no
current will pass except through the electro-magnet 31 which thus causes the
shaft 1 to become connected with the brush carrier 42.
On moving the handle 2 in one or the other direction, the motion of the
vertical shaft 1 is imparted to the movable part 14 of the stop-switch in such a
manner as to allow of the return of the current from the electro-magnet 31 only
through the stop 16 or 17ª corresponding to the direction of the motion.
the same time the movable contact piece 19 of the reversing switch will move so
as to send the current into the motor M in the desired direction.
At
The extent of movement of the handle 2 that is sufficient to effect this double
operation, corresponds exactly to the amount of play left between the pin 56 of the
armature 34 of the electro-magnet 31 and the tail-pieces 57 & 58 of the two
sectors 35 & 36. Consequently, the induced or armature coils of the motor M will
still be short-circuited and no motion of the motor will be produced. On continuing
to operate the handle 2, the brush-carrier 42 will be operated by the coupling
sectors 35 and 36 and the pinion 41. The brushes are then moved away from the
neutral contact-piece of the rheostat and come into contact with the active contact-
pieces thereof; the short-circuiting ceases, and the current is sent into the motor M
at a low potential. The potential increases with the extent of travel of the handle 2
until the brushes arrive at the contact-piece corresponding to the potential requisite for
starting. At this moment the motor M starts and its velocity of rotation will
gradually increase as the handle 2 moves towards its extreme position, which
corresponds to the maximum velocity. To every position of the handle 2 there
corresponds, as before, a definito velocity, which may thus be caused to assume all
values comprised between zero and the predetermined maximum.
When the handle 2 is moved back towards zero, the returning spring 48 causes
the corresponding sector 35 or 36 and the brushes to move back through all the
positions assumed during the first movement. The velocity of the motor M is thus
caused to diminish gradually until the motor stops altogether. At zero, the short-
circuiting is again produced. On continuing the motion of the handle 2 the

page_text: °
stop-switch and the reversing switch change the stop 16" or 17" in connection
therewith and the direction of the connections respectively. The second coupling
sector 35 or 36, as the case may be, then in its turn drives the pinion 41, and
consequently also the brush-carrier 42 until the electro-motor M assumes a rotary
movement in the opposite direction to that of the previous movement. By moving
the handle 2 very rapidly alternately to each side of zero, the notor M may be
caused to make successive fractional revolutions of any desired small extent.
Furthermore supposing the motor to be rotating at any given velocity, and the
lever 2 to be left in the position corresponding to that speed one of the stops 16 or 17°
of the part of the body or machine operated by the motor, will act, at the extreme
limit of the range of travel, upon the corresponding electric stop 16 or 17ª, and
the shunt current will be cut off automatically. At the same time, the motor will
be short-circuited and stopped instantaneously.
In order to start the motor
anew, the handle 2 must first be brought to zero. In this position the movable
contact 14 of the stop-switch will come into contact with the fixed contact-piece 53
or 54 corresponding to the other stop. The circuit is then closed, and all is ready
for motion in the opposite direction. Any false movement is impossible, because
the coupling circuit is remade only by the stop 16 or 17ª that has not operated,
and consequently only a return movement can be imparted to the moving part.
Any reverse movement of the handle 2 would have the result of again breaking the
coupling circuit.
The modified arrangement illustrated in Fig. 8 differs from that shown in Fig. 6
only by the omission of the two toothed sectors 26 and 27; in this case the operating
shaft 1 of the reversing-switch is connected directly to or formed in one with the
shaft 28 so that it is perpendicular to the axis of the rheostat. The mode of
operation is the same as that of the arrangement just described.
In the modified arrangement illustrated in Fig. 9, the bevel-sectors 35 & 36 are
replaced by spur-sectors, having respectively internal and external teeth. The
shaft 1 drives the shell of the electro-maguet 31 by means of two spur-sectors 26
& 27. The mode of operation is the same as that described with reference to
Figs. 6 & 7.
In the modified arrangement illustrated in Fig. 10, the two sectors 26 & 27 used
in the previously described arrangements are dispensed with, and the casing of the
electro-magnet 31 is keyed directly on the shaft of the reversing switch. The
mode of operation of this arrangement is the same as that of the arrangements
described with reference to Figs. 6 & 7.
In the arrangements illustrated in Figs. 6, 8, 9 and 10, when the operating
handle 2 is moved back into the zero-position the spiral spring 48 returns the
sectors 35 and 36 and the commutator-brushes to their initial positions. In order
to be able to stop and reverse the electro-motor by means of the handle 2 and
without any action on the part of the electric stops 16 and 17° notwithstanding the
failure of the spiral spring 48 for instance through the breakage of the same, the
following arrangement may be employed :-In the arrangement illustrated in
Figs. 14, 15, and 16 the solid pin 56 (Figs. 6, 8 and 10) is replaced by a tubular
pin 56 in which is arranged a cylinder 55 pressed outwards by a belical spring 55".
The cylinder 55 carries at one end a cross-piece 59 adapted to slide in two slots
formed in the pin 56. Each of the tail-pieces of the sectors 35 and 36 is formed
at its free end with a notch in which one of the ends of the cross-piece 59 is adapted
to engage (Fig. 16).
When the handle 2 is in the zero or stopping position, the cylinder 55 is situate
in front of the end of a stud 60 (Fig. 15) which compresses the helical spring 55.
On moving the handle 2 in any direction, the casing of the magnet 31 and the
armature will be rotated together with the cylinder 55; the end of the cylinder 55
thus escapes from the stud 60; and the helical spring 55° pushes the cylinder 55
outwards and causes.one of the ends of the cross piece 59 to enter the recess in the
tail-piece situate on the side towards the direction of movement. On moving the

page_text: IV
handle 2 back into the stopping position the pin 50 draws pach
piece that was previously pushed forward and thereby returns the two sectors 35
and 36 and the brushes of the commutator into the stopping position.
In the arrangement shown in Figs. 11, 12, and 13, the two bevel sectors 35
and 36, form one piece; and the sector 36 only is provided with a tail-piece 58,
which is formed with a notch in its end in which engages the pin 56 of the casing of
the magnet 31 (Fig. 12). The sectors 35 and 36 are arranged relatively to each
other (Fig. 12) in such a manner that the extreme tooth at the end of one sector
and the extreme tooth at the adjacent end of the other sector shall respectively
simply touch the pinion 41 (Fig. 13) so that when, in consequence of the movement
of the handle 2, the casing of the magnet 31 is rotated together with the sectors 35
and 36, one of the latter will engage with the pinion 41, and the other will move
away from the said pinion, so that when the handle is turned to the right or to the
left one or the other of the sectors 35 or 36 will actuate the pinion 41, and as the
two sectors engage alternately with the said pinion when moving in opposite
directions, the result will be that the pinion will be rotated in the same direction
whether the handle be turned in one direction or the other from its zero position.
In this arrangement, the sectors 26 and 27 may be dispensed with, as in the
arrangement shown in Fig. 8.
In all the arrangements hereinbefore described, the spiral spring 48 which serves
to return the brush carrier into the stopping position, may be replaced by an
equivalent device such as by a coiled spring fixed to the end of a cord a (Fig. 1)
wound on a drum or barrel fixed on the brush-carrier; or by a balance weight
working between two rollers or in a tube and attached to a cord wound on a barrel
fixed to the brush-carrier of the commutator.
The
The modification illustrated in Figs. 17 and 18 has the same object as the
modifications illustrated in Figs. 11 to 16 inclusive. In this arrangement, the
intermediate shaft 28, instead of being horizontal, is arranged vertically in line
with the operating-shaft 1. The shaft 28 carries a metal sleeve 61 which ends in
a pinion 62 at its upper part and on which is fixed the electro-magnet 31.
armature 34 is keyed to or forms one piece with the brush-carrier 42 and is loose
on the shaft 28. The connection between the operating-shaft 1 and the inter-
mediate shaft 28 is effected by means of a slotted guide 63 provided at its lower
part with a rack 64 gearing into the pinion 62. This slotted guide receives a
to-and-fro movement by means of a roller 65 carried by an arm 66 keyed on the
lower end of the operating-shaft 1. The armature 34 having been attracted by
the electro-magnet 31 and the operating-lever 2 being at zero, the various parts
will be in the position shown in full lines in Fig. 18. If, then, the handle 2 be
moved in one or the other direction, the lever 66 will be moved to a corresponding
extent, but without causing auy movement of the rack so long as the roller 65
rolls on that portion of the slide 63 that is co-axial with the operating-shaft 1.
This period corresponds to the duration of the motion of the switches whilst
changing the stop 16 or 17" (Figs. 5 and 7) for the time being electrically
At this moment
connected, and reversing the current in the electro-motor M.
the rolling motion of the roller 65 in the slide 63 causes the rack 64 to move and
to rotate the pinion 62 and thus shift the brushes on the cominutator 43. In
returning the handle to zero, the same phases are reproduced but in a reverse
manner the motion of the slide 63 causing the return of the brush-carrier 42
independently of the returning-spring 48. Similarly, when the operating handle 2
has passed beyond zero in order to change the direction of rotation of the electro-
motor M, the reversal takes place first, as in the previous case. and then the
rack 64 by its longitudinal motion (which is the same as when the rotation of the
handle is in the reverse direction) carries with it the pinion 62 and the brush-
carrier 42. The apparatus herein before described and its various modifications
may be controlled directly by means of a hand operated lever as illustrated in
the accompanying drawings, or from a distance by means of electro-motors,
solenoids, or other suitable electrical apparatus.

page_text: Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
1. Apparatus for starting stopping & controlling an electro-motor adapted for
operating bodies or machines of the kind hereinbefore referred to having a limited
movement, comprising an operating-shaft 1 on which are keyed the movable part 14
of a stop-switch haring four fixed contact-pieces, and the movable part 19 of a
reversing-switch having six fixed contact-pieces of which two viz. 20 and 21 are to
be electrically connected with the entering terminals of the circuit from the
generating dynamo when the apparatus is in use, two others viz. 23 and 24 are to
be electrically connected with the terminals of the electro-inotor, with which the
apparatus is combined, whilst the other two viz. 22 and 25, are neutral or dummy
contacts, an electro-magnetic clutch consisting of two electro-magnets 31 and 32
mounted to turn freely on an intermediate shaft 28, and a movable double
armature 33, 34 fast on the said shaft, the two shafts being connected by sectors 26
and 27, a rheostat provided with a commutator 43, a shaft 40 co-axial with the
shaft and carrying an operating arm 42 having a brush-carrier 44 with brushes
which are constantly in contact with the periphery of the said commutator 43; and
a returning spring 48 fixed to the shaft 40 and to the brush-carrier 42 and serving
to move the brushes back onto the neutral contact-piece of the commutator when
the circuit of the electro-magnetic clutch is broken automatically by means of the
electrical stops operated by the bodies or machines operated by the motor, all
substantially as herein before described with reference to and shown in Figs. 1 to 15
inclusive of the accompanying drawings.
2. Apparatus of the kind specified in the preceding claim modified substantially
as hereinbefore described with reference to and shown in Figs. 6 and 7 of the
accompanying drawings so that the connection between the operating-shaft 1 and
the brush-carrier 42 is effected by a single magnetic clutch.
3. Apparatus of the kind referred to in Claim 1, modified substantially as
herein before described with reference to and shown in Fig. 8 of the accompanying
drawings so that the toothed sectors 26 and 27 (Figs. 1 to 4 and Fig. 6) are
dispensed with and the olf
ersing-switch is brought perpendicular to
that of the commutator.
4. Apparatus of the kind 11. to in Claim 2, modified substantially as
described with reference to and shown in Fig. 9 of the accompanying drawings,
so that the axle of the reversing-switch rotates the casing of the electro-magnet 31
by means of two toothed sectors 35 and 36.
5. Apparatus of the kind referred to in Claim 2, modified substantially as
herein before described with reference to and shown in Fig. 10 of the accompanying
drawings, wherein the casing of the electro-magnet 31 is keyed direct on the axle
of the reversing-switch.
6. In apparatus of the kind referred to in Claim 1, a tubular pin within which
is arranged a cylinder 55 carrying a cross-piece 59 each of the ends of which is
adapted to engage in a notch formed in the end of one of the tail-pieces of the
sectors 35 and 36 used for operating the brush-carrier from the electro-magnetic
clutch, substantially as described with reference to and shown in Figs. 14, 15
and 16 of the accompanying drawings, whether or not the sectors 26 and 27 be
dispensed with substantially as herein before described with reference to and shown
in Fig. 8 of the accompanying drawings.
7. Apparatus of the kind referred to in Claim 2 modified substantially as
herein before described with reference to and shown in Figs. 11, 12 and 13 whereby
the brush-carrier is operated from the armature of the electro-magnetic clutch
through two sectors 35, 36 made in one piece and having a single tail-piece engaged
by the said armature.
8. Apparatus of the kind specified in Claim 1, modified substantially as
berein before described with reference to and shown in Figs. 17 and 18 of the

page_text: accompanying drawings, so that the intermediate shaft 28 is co-axial with the
operating-shaft 1 and the magnet 31 is fixed on the shaft 28 by means of a sleeve
as set forth.
Dated this 30th day of July 1894.
F. WISE HOWORTH,
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicants.