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Патент USA US2125876

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Aug- 9, 1938-
J. H. BARTHOLOMEW
I
2,125,876
AUTOMATIC LEVELING SYSTEM FOR ELEVATORS
Filed Oct. 10, 1956
L3
63
55
3 Sheets-Sheet 1
L2
1 N VENTOR.
JA/VEJ H a/w/mw/vm
wage/Q. Mm.
ATTORNEY.
Aug. 9, 1938.
2,125,876
J. H. BARTHOLOMEW
AUTOMATIC LEVELING SYSTEM FOR ELEVATORS
Filed Oct. 10, 1936
s Sheets-Sheet 2v
INVENTOR.
J/W?i ?KB/I/f’T/VOLO/VEW
Aug- 9; 1938.
J. H. BYARTHQLQ-MEW
2,125,816
AUTOMATIC LEVELING SYSTEM FOR ELEVATORS
INVENTOR.
BY
ATTO
EY.
Patented Aug. 9, 1938
UNH'EED STzii-t'i‘Exg
@Fi‘lilil
' 2,125,876
AUTOMATIC LEVELING SYSTEM FOR ELE
VATORS
James H. Bartholomew, Warsaw, N. Y.
Application October 10, 1936,, Serial No. 105.0%
19 Claims.
The present invention relates to an automatic
leveling system for elevator cars and more par
ticularly to an electro-mechanical type of auto
matic leveling system.
Although automatic leveling systems for ele
vators are known, the present practice is to em
ploy controls which are fully electrical and which
include complicated and expensive electrical
equipment and circuits and which are compara
O tively expensive to install and maintain.
The primary object of the present invention is
the provision of an electro-mechanical automatic
leveling system for elevators which is simple in
construction and essentially mechanical in op
15 eration.
Another object of the invention is an electro
mechanical leveling system for an elevator car
adapted to be leveled with respect to a plurality
of ?oors or landings, which is mechanically and
20 easily adjusted and which is economically main
tained.
‘
A further object is the provision of a leveling
-"
with the leveling relay shown as when the ele
vator car is level with the corresponding ?oor.
Fig. ‘l is also a side elevation similar to Fig. 2
but with the leveling relay shown as when the
elevator car is approaching the corresponding 5
floor.
Fig. 5 is a front elevation of the leveling relay
and limit arms for a ?oor and with the same in
positions also shown in Fig. 4 as when the ele
vator car is approaching the corresponding ?oor. iii
An elevator system according to the present in
vention is diagrammatically illustrated in Fig, 1
and may be installed in a structure iii which is
provided with a hatchway ii. A plurality 0':
floors or landings i2a, I21) and lZc are spaced 57-‘
along said hatchway II and a pair of hatchway
doors ‘l3 are mounted at each of said ?oors or
landings.
The elevator car M is guided within said
hatchway II in any suitable and conventional 20
manner. A cable drum 1 5 may be mounted above
the hatchway l I and may be encircled by a main
cable l6 which has one end attached to the car
I4 and the other 'end attached to a counter
relay corresponding to each floor of the elevator
hatchway, which is operative only when the ele—
vator car is adjacent the respective floorand
weight l‘! moving in said hatchway l i and coun
which is mechanically controlled by the position
terbalancing said car l4.
of the elevator car with respect to said floor.
Still another object of the invention is the pro—
vision of a leveling relay including a pair of
may be raised and lowered by rotation of said
cable drum l5 which is operated through any
known type of connection, such as a gear train,
Said elevator car M
control contacts, an armature carrying one of
by a suitable prime mover, such as an electric 39
said contacts, a magnetic coiljforlattract'ing" said
‘motor l8. Said motor i8 is connected by a. shaft
armature, and a contact arm carrying the other
of said contacts and moved to open the same
l9, indicated by the broken line in Fig. 1, to a
when the elevator car is level with the ?oor even
worm 20 which meshes with a worm wheel 2|
in turn connected to a cable drum l5 by a shaft
35 though said magnetic coil is still energized.
Other and further objects of the invention will
be suggested to those skilled in the art by the
22, also indicated by broken lines in Fig. 1.
though the invention is to be described with
respect’ to a traction type elevator drive from
accompanying disclosure.
’
an electric motor ‘to the elevator car, it is under
I
To attain the said above and ‘other objects,
40 the invention consists'in certain improvements
and combinations of parts an as fully set forth
in the following speci?cation and de?ned in the
appended claims.
.
Reference is hereby made to the accompany“
ing drawings wherein like reference characters
designate similar elements and wherein:
.
Fig. 1 is a complete diagrammaticillustration
of the invention including the essential mechan
55) ical members as well
circuits.
necessary electrical
~
-
Fig. 2 is a side elevation of the leveling relay
and limit .arms for one floor and showing the
relay in inoperative condition.
55
Fig. 3 is a side elevation similarv to Fig. 2 but
stood that the invention is equally applicable to
all types of drives and prime movers now known 40
to the art.
’ '
‘
The'electric motor i8 is preferably of the three
phase, two speed type and has a high ‘speed
winding 23 and a low speed winding 24. A three
phase source of electric power is available 45
through the supply mains Ll, L2 and L3. The
motor circuits are conventional, are connected
across said supply mains Ll, L2 and L3, and. are
illustrated by heavy lines in Fig. 1.
The high speed motor circuits comprise a con- 50
ductor 25 extending from supply main L! to one
leg of high speed winding 23 and including a
pair of contacts 26 and a pair of contacts 2?, a
conductor 28 extending from supply main L2
to another leg of high speed winding 23 and 55
2
2,125,876
including a pair of contacts 29, and a conductor
30 extending from supply main L3 to the other
leg of high. speed winding 23 and including a
pair of contacts 3|. Said high speed winding 23
of the motor I8 is reversed by reversing the con
nections of supply mains LI and L3 thereto.
For this purpose, a conductor 32 extends from
a point of conductor 25 to a point on conductor
30 and includes a pair of contacts 33, and a con
ductor 34, including a pair of contacts 35 ex
tends from a point on conductor 30 to one of
contacts 21 through which it is connected to
conductor 25.
The low speed motor circuits comprise a con
ductor 36 which is connected through conductor
25 to supply main LI, which extends to one leg
of low speed winding 24, and which includes a
pair of contacts 31, comprise a conductor 38
which is connected through conductor 28 to sup
ply main L2, which extends to another leg of low
speed winding 24, and which includes a pair of
contacts 39, and comprise a conductor 40 which is
connected through conductor 30 to supply main
L3, which extends to the other leg of low speed
winding 24, and which includes a pair of contacts
4|. Reversal of said low speed winding 24 may
be accomplished through a conductor 42 which
includes a pair of contacts 43 and which is be
tween conductors 36 and 40 to connect the last
mentioned leg of said low speed winding 24 to
supply main LI, through a conductor 44 which in
cludes a pair of contacts 45 and which is between
said conductors 36 and 40 to connect the ?rst
mentioned leg of low speed winding 24 to supply
main L3, and through a conductor 46 which in
cludes a pair of contacts 41 and which bridges a
portion of conductor 38 to connect the middle leg
of low speed winding 24 to supply main L2.
The motor control circuits may be connected
between supply mains LI and L2 and include a
tacts 21, and includes a rod 82 also attached to
armature 18 and carrying a contact arm 83 for
closing contacts 15. A spring 84 is connected to
said contact arm 83 normally to hold the same in
closed position and said contact arms 89 and BI
in open positions.
An up leveling contactor 85 comprises a coil 86,
an armature 81, and a rod 88 carrying a contact
arm 89 for closing contacts 39, a contact arm 90
for closing contacts 4|, and a contact arm 9| for
closing contacts 31. A down leveling contactor
92 comprises a coil 93, an armature 94, and a rod
95 carrying a contact arm 96 for closing contacts
41, a contact arm 91 for closing contacts 45, and
a contact arm 98 for closing contacts 43. Said
leveling contactors 85 and 92 are of a well known
type with armatures 81 and 94 both normally
biased to open positons but adapted to be moved
to closed positions upon energization of the re
spective coils 86 and 93.
The energization of said up and down leveling
contactors 85 and 92 is supervised by a plurality
of control circuits and by a plurality of leveling
relays 99, each of which 99a, 99b and 990 corre
sponds to each of floors I2a, I21) and I20 in the -
hatchway II. The particular construction of
such leveling relays 99 will next be described in
connection with Figs. 2—5 inclusive.
Each leveling relay 99 comprises a base mem~
ber I00 to which is attached a bracket IOI and a .'
magnetic coil I02. Said bracket IilI has a pair of
journals I03.
An armature I04 includes an arm
I05 which is pivoted between said journals I03 by
a pin I06 and includes a contact support I01
which is fastened to arm I05 and which carries
two motor control contacts I08 and I09.
The motor control contact I 08, see Figs. 2, 3 and
4, is mounted on a stem I I0 which has a threaded
end passing freely through contact support I01
car switch 48 including a pair of up terminals 49
and 50 and including a pair of down terminals
and carrying an adjustable nut I I I. A coil spring VII)
I I2 encircles stem III) and normally urges con
tact I08 to an extended position with nut III
5| and 52. Wires 53 and 54, respectively, connect
terminals 49 and 5| to supply main LI, while a
Cl wire 55 connects up terminal 50 to supply main
L2 and a wire 56 connects down terminal 52 to
supply main L2. A wire 51 is connected to sup
ply main L2, has a branch 58 which includes a
pair of contacts 59 and which is connected to
50 wire 55, and has a branch 60 which includes a
pair of contacts 6| and which is connected to
wire 56.
An up contactor 62 includes a coil 63 which is
in series with wire 55 and includes a rod 64 which
is operated by said coil 63 and which carries a
contact arm 65 for bridging contacts 59, a con
tact arm 66 for bridging contacts 26, and a con
tact arm 61 for bridging contacts 3|. A down
contactor 68 includes a coil 69 which is in series
with wire 56 and includes a rod 10 which is
operated by said coil 69 and which carries a con
tact arm 1| for bridging contacts 6|, a contact
arm 12 for bridging contacts 35, and a contact
arm 13 for bridging contacts 33.
The motor control circuits for the low speed
operation of the elevator car I4 include a bus wire
of motor control contact I08 may be varied by
adjustment of nut III. Contact I09» is also re 45
siliently and adjustably supported in an identical
manner by a stem I I3 and nut I I4, see Fig. 5.
Armature I04 includes abutments II5 which
comprise a T-shaped arm I I6 fastened to arm I05
and carrying a pair of adjustable thumb screws
H1 and H8. Said armature I04 and abutments
II5 are normally in the position shown in Fig. 2.
A pair of bearings H9 and I20 are mounted on
said base member I00, a contact arm I2I is jour
naled on bearing II9 by a pin I22, and a contact
arm I23 is journaled on bearing I20 by a pin I24.
A motor control contact I25 is mounted upon the
upper end of contact arm I2I by a stem I 26 which
is threaded into said contact arm I2I and locked
in an adjusted position by nut I21. A motor con 60
trol contact I28 is mounted upon the upper end
of contact arm I23 by a stem I29 which is thread
ed into said contact arm I23 and locked in its
adjusted position by a nut I30, see Fig. 4.
14 which is the only connection between supply
main L2 and said low speed motor control cir
cuits and which includes a pair of contacts 15.
A high speed control contactor 16 includes a coil
11 which is in series with wire 51, includes an
armature 18 operated by said coil 11, includes a
rod 19 which is attached to said armature 18
and which carries a contact arm 80 for closing
contacts 29 and a contact arm 8| for closing con
against said support I01, which extended position
The lower end of contact arm I 2| has a por
tion I3I which is provided with a bifurcated end
for supporting the axle I32 of a roller I33 while
a roller I34 is similarly supported upon the lower
end of portion I35 of contact arm I 23, see Fig. 4.
The contact arms I2I and I23 are so propor
70
tioned and balanced upon their respective bear
ings H9 and I20 that both of said contact arms
I2I and I23 have a normal tendency to rotate
in a clock-wise direction. Stops are respectively
provided to limit this normal movement of the 15
3.
2,125,876
contact arms iii and I23 and may each comprise
a thumb screw use extending through base mem
may engage the roller !33 on contact arm I“,
see
Ll, while the other contact arm l23 assumes
ber m8 and adjustably fastened thereto by nuts
[3]. Similarly stops are also respectively pro
its normal position abutting against the respec
vided to limit the rotation of the contact arms
till and its in a counter-clockwise direction and
may each comprise a thumb screw E38 extend
ing through base member E63 and adjustably fas
tencd thereto by nuts ltd.
Resilient members are mounted between said
armature ass and the respective contact arms
52! and H33 normally to separate the contacts
thereon. For instance, a leaf spring MS may be
fastened on contact support liil’ opposite contact
tive thumb screw 53%, or alternatively arcuate
sector M2 on. limit arm
floor E2, the gap between said arcuate sectors
will be opposite said rollers i153 and i345 so that 10
both contact arms l i and E28 will rest against
thumb screws 53¢ as shown in Fig. 3.
The radial extent or" limit arms 55? and I58
' rote sectors Mil and M52 may be greater
1
l . than the radius of control 15
arm l2! so as not to engage the same when the
magnetic coil M32 is not energized, see Fig. 2,
but adapted to bear on said contact arm li'il and
tending to separate motor control contacts Hi8
and H25 as shown in Fig. 3 when the magnetic
coil I532 is energized. A second leaf spring tail
may also be fastened to contact support Mil oppo
As will be readily understood, the ac
curacy of the leveling operation is increased when
" --
l e '
are shown in the diagrammatic illustration of
30 Fig. 1 and each element shown therein is des
ignated by the general reference numeral and
it oi‘ said limit arms is greater
rlius of drum
because the extremi
limlt arms l5? and E58 are then 20
than car speed and the movement
- car lb”.- is magnified at the end-s of said
Site contact arm E23 and tends to separate motor
control contacts Hi9 and W8 upon energization
of said coil H32, see Fig. 5.
As before mentioned. there are leveling relays
99a, 99b, and 990 corresponding to each of the
floors l
lzb, and Me. Only the essential ele
ments of said leveling relays 9530!, $917, and 99c
may engage the
roller ltli on contact arm 523. Furthermore, said
limit arms trail‘ and 5&3 are also adjusted on shaft
555 so that when car
is exactly level with the
limit
so that said rollers H33 and
25
a
l.
ated herein, the limit arms l5? and
we rotate in a clockwise direction when the car
5 moving upwardly and in a counter-clockwise
_ recti
it is moving downwardly, 30
when car
see arrows
Figs. 2, 8 and ll.
Also the zone
an alphabetical character corresponding to the
floor 112a, i217 or l2c at which the relay controls
a counter-clockwise direction when the car is
leveling.
moving upwardly.
A mechanical control means operated by the
elevator car M supervises the energization of the
magnetic coil iii? of the leveling relay 99 as well
as the positions of contact arms l2! and M3 as
stood that said arms may rotate in either direc
tion as long as their relative timing meets the
conditions later to be set forth.
said car iii approaches or stops at a ?oor or land
65% and i582), and idle and 85550 are pro
vided on shaft 555 and each pair corresponds to 40
one of the floors lilo, l2?) and We, see Fig. 1.
It is obvious that when the magnetic coil m2
of each leveling relay Qt} is not energized that the
ing.
Such. a mechanical control means includes a
control drum ill-2 mounted above the hatchway
H and encircled by a control cable M3 which
is fastened to the car M by a bracket 5M and
Which is maintained under tension by a pulley
M5 and a weight
, see Fig. 1. A shaft Ml is
journaled in bearing M3 and is attached to
One end of control drum M2. A gear M9 on
shaft Ml meshes with a gear 558 on a shaft
l?i which is iournaled in bearings E52.
The
ratio between gears M9 and H9 is selected so
that shaft iii-i makes less than one complete
revolution, or turns through about 340°, during
travel of the elevator car it along the entire
height of the hatchway ii. A plurality of zone
arms 553 are mounted in angular relation upon
said shaft iol and are each adjustable upon said
shaft l5! by means of set screws lEeél. Each
zone arm l53c, Highland
see Fig. 1, corre
sponds to each floor 52a, 52b and lilo.
Said mechanical control means also includes
a shaft
journaled in bearings Hi6 and at
tached to the other end of control drum M2. A
plurality of pairs
limit arms l5? and 558 are
__
is in icated by the arrows as rotating in
However, it is to be under
A. plurality of pairs of limit arms lbla and
contact
512i and W“ on each relay 99 are
intained
the posit ons illustrated in Fig. 2
by the abutments M5 on armature Hi4 so that
there is ample clearance between rollers £33 and
i313 and the arcuate sectors HM and i62 on the
limit arms l5? and 558, otherwise the thumb
"no
screws and/or M8 on said armature [94 are ad
justed so that there is suflicient clearance be
tween said rollers M3 and i345 and said sectors
i?l and H52.
Upon energization of the magnetic coil Hi2,
the attraction of armature its frees said contact
arms i2! and i273 so that the rollers i553 and H34
thereon move into the paths of the sectors l5! and
ill-.12 on limit arms till’ and
but such energi
zation of the magnetic coils
ltilb and I620
is selectively controlled and takes place only when
the elevator car it is near the corresponding floor
we, lflb or £20 in a roanner next to be described.
The energizing circuit for each magnetic coil
adjustably fastened to shafiL 555 by representative
includes a pair of zone contacts its and I64
set screws 559 and 5%, see Fig. 5. An ar‘cuate
sector 516i i mounted upon the end of limit arm
i5? and an arcuate sector 562 is mounted upon
the end oi.’ limit arm
Said limit arms E57 and
are angularly displaced with respect to each
m
other so that a
is provided between the ad.
‘ch
normally open, contact E54 being oper
ated by an actuating rod
Said actuating rod
jacent ends of said arcuate sectors i?l and 662,
see Figs. 2, 3 and 4. Said limit arms it“)? and
E56 are also spaced longitudinally of said shaft
15 I55 so that the arcuate sector It! on limit arm I57
60
i
is positioned so as to be operated by the zone
a whereupon
contacts i233 and E54
iosed, see Figs. 3 and ll. The zone arm H53 KY (
lgned and angularly adjusted on shaft l5!
so tnat said contacts
and i643 are closed only
the elevator car it is in the vicinity of the
r
corresponding to the particular set of
contacts i623 and
and zone arm i515.
Contact
4
2,125,876
I63 is connected to one side of magnetic coil I02
by a wire I66‘.
The several control circuits are connected to
supply main LI by a bus wire I61, see Fig. 1.
The energizing circuit for leveling relay 990 com
prises a wire I680 extending from bus wire I61
to zone contact I630, a wire I660 extending from
zone contact I640 to one side of magnetic coil
I020, and a wire I690 extending from the other
side of magnetic coil I020 to bus Wire 14. The
energizing circuit for leveling relay 990 includes
a wire I68b extending from bus wire I61 to zone
contact I631), a wire I661) extending from zone
contact I64b to magnetic coil I02b, and a wire
I69b extending from magnetic coil I021) to bus
wire 14. The energizing circuit for leveling re
lay 990 includes a wire I680 extending from bus
wire I61 to zone contact I630, a wire I660 from
zone contact I640 to magnetic coil I020, and a
wire I690 from magnetic coil I020 to bus wire 14.
The motor control contacts I08 and I09 on
the armature I04 are each connected to bus wire
I61, motor control contact I090 being connected
to bus wire I61 by wire I100, and motor control
contact I080 being connected to bus wire I61 by
a wire I1I0. Wires I10b, I1Ib, I100 and I1Ic,
respectively, connect motor control contacts I091),
I081), I090 and I080 to said bus wire I61. The
motor control contacts I280, I28b and I280 on
the contact arms I230, I23b and I230 are respec
ing contactor 85 in closed position which should
not be confused with the conditions when the
elevator is stopped at any particular floor.
Assume that the operator on the car I4 moves
the car switch 48 upwardly. The up terminals
49 and 50 of said car switch 48 are bridged and
up contactor 62 is placed across supply mains
LI and L2. Upon energization of up contactor
62, rod 64 is raised, contact arm 66 closes con
tacts 26, contact arm 61 closes contacts SH, and 10
contact arm 65 closes contacts 59 so that coil 11
of high speed contactor 16 is energized. Such
energization of said coil 11 moves rod 10 against
the action of spring 84 so that contact arm 89
closes contacts 29 and contact arm 8i closes con
tacts 21. The three phase high speed winding 23
of the motor I8 is now fully energized and the
car I4 will be raised at full speed.
At the same time energization of coil 11 has
moved rod 82 to withdraw contact arm 83 from 20
contacts 15 and since all other energizing or
control circuits are fed through contacts 15 they
can not now become operative during high, spear
operation of the car I4. For instance each time
that car I4 approaches one of the ?oors I20, 25
I20 or IE0, the zone arms I530, I531) or
E330
close the contacts I630 and I640, I63!) and I641),
I630 and I640, respectively, but since contacts
15 are open, none of the energizing circuits or
magnetic coils I02 can be energized so that the 30
tively connected by wires I120, I12?) and I120 to
leveling relays 99a, 99b and 990 maintain the
a wire I13 which leads to one side of the coil 86
position illustrated in Fig. 2 and the sectors I6I
and I62 of limit arms I51 and I50 pass rollers
I33 and I34 without engaging the same.
When the car is approaching a ?oor I2 at 35
which it is desired to stop, the operator moves
the car switch 48 to the open position shown in
Fig. 1. Assuming that the car has been moving
upwardly toward floor I20, see Fig. 1, the con
tactors 62 and 16 are opened and the high speed 40
winding 23 of motor I8 is cle-energized. At the
same time, however, zone arm I530 has operated
actuating rod I650 to close zone contacts I630
and I640. Now since contactor 16 is de-ener
gized contacts 15 are closed by contact arm 83
and magnetic coil I020 is energized through the
energizing circuit, as previously traced, between
supply mains LI and L2. Furthermore, the ar
of up leveling contactor 85, the other side of
said coil 86 being connected to bus wire 14 by
L9 221 a wire I14. The motor control contacts I250,
I251) and I250 on contact arms I2I0, I2Ib and
I2I0 are respectively connected by wires I150,
I15!) and I150 to a wire I16 which extends to
one side of coil 93 of the down leveling contactor
40 92, the other side of said coil 93 being connected
to bus wire 14 by a wire I11.
There are two motor control circuits for each
floor, one circuit being an up leveling control
circuit and the other a down leveling control
circuit. For instance the up leveling control cir~
cuit for ?oor I20 may be traced as follows: from
supply main LI, wire I61, wire I100, contacts
I090 and I280 respectively on armature I040 and
contact arm I230 of leveling relay 990, wire I120,
wire I13, up leveling contactor coil 86, wire I14,
bus wire 14, through contacts 15 and contact
arm 83 to supply main L2. The down leveling
control circuit for floor I20 is from supply main
LI, wire I61, wire I1I0, contacts I080 and I250
55 respectively on armature I040 and contact arm
I230 of leveling relay 990, wire I150, wire I16,
down leveling contactor coil 93, wire I11, bus
wire 14, through contacts 15 and contact arm 83
to supply main L2. The up and down leveling
60 motor control circuits for the other floors are
similar to those just traced and it is pointed out
that the motor control contacts are paired so that
motor control contacts I090 and I280, I080 and
I250, I090 and I280, I08b and I251), I090 and
65 I280, I080 and I250, make or break contact with
each other to close or open the respective motor
control circuits.
The operation of the automatic elevator level
ing system according to the present invention
70 will now be described.
When the elevator car I4 is stopped at a floor,
the contactors 62, 68, 16, 85 and 92 are all in
their normally open positions and all motor con
trol circuits and all motor circuits are open.
75 Fig. 1 illustrates another condition with up level
cuate sector I620 on limit arm I580 is now in
position to engage the roller I340 on contact 50
arm I230, see Fig. 1, and hold the motor control
contact I280 therein in position to make with
the contact I090 on armature I040 which is now
attracted by magnetic coil I020. On the other
hand, the arcuate sector I6I0 on limit arm I510 55
is not opposite roller I330 so that contact arm
I 2I0 swings to inoperative position against the
thumb screw I36 and motor control contacts
I02-0 and I250 remain open.
Since motor control contacts I090 and I280 60
are closed, the motor control circuit to up level
ing contactor 85 is completed across supply mains
Li and L2 so that the coil 86 is energized and the
rod 88 is operated to move contact arm 09
against contacts 39, contact arm 90 against con 65
tacts 4|, and contact arm 9| against contacts 31.
Closure of said contacts 31, 39 and 4| places the
three phases of the low speed motor Winding 24
across the three phase supply mains Ll, L2 and
L3 so that the elevator I4 continues to move up 70
wardly but at low speed.
Since contacts I380
and I250 are open, down leveling contactor 9?
can not be energized. This condition of the zone
arm I530, zone contacts I630 and I640 being
closed, blocking of contact arm I230 by limit arm 75
2,125,876
[58a to close motor control contacts l?9a and
Mia upon energization of magnetic coil Wild and
energization of up leveling contacting 85 to close
the motor circuits to the low speed up winding
24 of the motor I3 is indicated in Fig. 1.
The elevator car is now moving upwardly at
low speed. The arcuate sector lt?a and limit
arm l58a are so designed and located so that
roller Nita is disengaged and contact arm l23a
moves to its normal position under the action of
spring Ml which also causes a quick break be
tween motor control contacts iUSid and izlia
precisely when the platform of the elevator car
l4 becomes even or level with the floor 52a.
15 Opening of contacts lii8a and @2067» de-energizes
upleveling contactor 35 to open contacts 3?, 39
and M and de-energizes the motor winding 24
so that the car M is stopped. In case the opening
of contacts lElQa and l28a is not timed just
right, the limit arm 558a may be angularly ad
justed on shaft £55 to correct the time for
opening of said contacts lBSa and IZBa or the
adjustable mountings for contacts 589a or 128a
may be adjusted by appropriate adjustment of
nuts I [4 or 83% to retract or project said contacts.
If the car switch [33 is moved downwardly to
bridge the down terminals 51 and 52 thereof,
down contactor S8 and high speed contactor '86
are energized and the high speed winding 23 of
30 motor I8 is connected across supply mains Ll,
L2 and L3 in such phase relation that the motor
I8 is reversed and the car It moves downwardly.
At the same time contacts 75 are opened so that
none of the leveling control circuits can be
energized.
Opening of the car switch 48 as the car 84 is
lowered toward a floor at which it is desired to
stop will de-energize the high speed motor wind
ing 23 and contacts it“: will be closed by the con
current de-energization of high speed contactor
‘l6. Assume that the car it is moving down
wardly toward floor i2b, zone arm I531) will be
in engagement with actuating rod i651? and zone
contacts H531) and i642) will be closed to complete
the energization circuit through magnetic coil
“32b.
Limit arm ll'o'i'b is so located or timed
5
floor at which it is stopping the other roller will
ride up on the arcuate sector of the other limit
arm and the motor control contacts for moving
the car in the opposite direction will be closed.
Speci?cally, if such over shooting took place
during the down leveling at floor l2b as just de
scribed, rcller 534?) would ride up on arcuate sec
tor 5152b so that contact arm 5232) would be
moved to close motor control contacts HlSb and
l28b. It should be noted that the limit arms l5‘!
and E58 are moved independently of the main
cable NS for the car l4 so that stretching thereof
does not affect the proper timing or positioning
of said limit arms. Since the up motor control
contacts i 8% and i281)‘ are closed by such down 15
ward overshooting, up leveling contactor 85 is
energized and the car moves upwardly at low
speed but now under the control of limit arm
M21). The cessation of this return movement is
then controlled as previously explained with re 20
spect to the up leveling conditions.
It should also be noted that zone contacts H63
and I64 are always closed by zone arm 853 when
the car is at or near the corresponding ?oor I2
and irrespective of whether the car I4 is moving
or is stopped. Hence if for any reason the car
M should raise or drop after having come to a
stop level with the floor, the corresponding level
in‘:r relay 99 remains energized and the proper
roller E33 or 136 rides up on the corresponding
sector Hit or H62 so that the leveling operations
are repeated to re~level the car with respect to
the ?oor. The extreme normal positions of roll
ers i153 and we are predetermined by the ad
justment of thumb screws i365 so that said roll 35
ers E33 and 5341 will ride up on said sectors Hi!
and E62 during the re-leveling functions of the
leveling relay 99.
The zone arms W3 and limit arms l5] and H8
are preferably timed with respect to each other
so that the magnetic coil i532 of the leveling relay
is not energized at least until the leading edge
of the arcuate sectors lBl and 562 are in posi
tion to engage either roller i33 or ltd respectively.
This condition is assured because the zone arms 45
i533 move through a relatively small angle since
that its arcuate sector Hill) is now in position
to engage roller I332) when armature NW) is en
ergized and contact arm i2ib is swung upwardly
50 so that contacts i631) and i251) are closed. How
ever, since the car M is moving downwardly
roller 136?,“ is not engaged by the sector i622: on
limit arm i581) so that contacts H3919 and I282)
they are operated through reduction gears H29
are open under these conditions which are illus—
limit arms l5? and i583 may all be located at one
place such as in the pent-house or motor room
above the elevator hatchway. Hence it is a sim
CI in trated in Fig. 4.
Since contacts H381) and i251) are closed, the
and use while limit arms l5? and 958 are mov
ing at greater than car speed and travel through
a relatively large angle.
One outstanding feature of the automatic ele 50
vator leveling system of the present invention is
that the leveling relays 99, zone arms I53 and
motor control circuit to down leveling con
tactor 92 will be completed across supply mains
Li and L2 and the low speed down motor con
tacts d3, I35 and 47 will be closed by contact arms
ple matter to make any of the necessary adjust
ments to control the operation and accurate level
ing of the car. Such adjustments, as have been
98, 9V and 98, respectively, of said down leveling
of the zone arms E53 upon shaft l5! by means
contactor Q2.
The car it is now moving down
wardly at low speed and said arcuate sector Hill)
on limit arm it'll) disengages roller i331) under
' the action of spring 114% to open motor control
contacts iil?b and i251) precisely so that down
leveling contactor 92 is lie-energized and said
low speed down motor contacts 43, £55 and 41 are
opened to stop said car It with its platform level
~. with floor l2b.
Again in case this timing is not
quite accurate limit arm i571) may be angularly
adjusted on shaft E55 or contacts l08b and I25a
may be adjusted to correct the timing.
If, for any reason, such as slip in the brake
or cable stretch, the car t4 should overshoot the
previously explained, may be angular adjustment 60
of set screws EM, may be angular adjustment
of limit arms i511 and [58 upon shaft H55 by
means of set screws its and 160, respectively,
to alter the timing. of said limit arms l5‘! and
65
558 with respect to said zone arms i5?» and of
the arcuate sectors it! and M2 on limit arms
i5“! and‘ @558 with respect to said rollers E33 and
934%’, respectively, or may be leveling relay ad
justments such as adjustment of the motor con 70
trol contacts W8 and M9 by means of nuts iii
and’ M4 and motor control contacts I25 and H8‘
by means of nuts iZ'l and itt for ?ne adjustment
of the timing of the motor control contacts, such
as adjustment of the thumb screws H7, H8, I36
6
2,125,876
and I38 to vary the extreme positions of the con
tact arms iii and I23 for clearance between sec
tors IEI and I62 and rollers I33 and H4, see
Fig. 2, and for adjustent of the normal inopera
tive positions of said contact arms HI and I23,
see Fig. 3.
Although the high speed motor control cir
cuits are completed and opened by the car switch
48, it is obvious that other types of motor con
trol switches, such as push buttons, may be used
at the floors or on the cars. It is also understood
that standard equipment such as brakes, gate
switches, interlocks, etc., will in general be used
with the leveling system of the invention but such
equipment has not been illustrate-d or described
because the provision and application thereof
will be realized by those skilled in the art.
Since many variations of the invention are pos
sible, the present disclosure and description are
20 to be construed in an illustrative sense, the scope
or said invention being de?ned in the appended
claims.
Having now particularly described my inven
tion, what I desire to secure by Letters Patent of
the United States and what I claim is:
1. In an automatic system for leveling an ele
vator car with respect to a ?oor, the combina
tion with a prime mover connected to said ele
vator car and for moving the same with respect
30 to said floor, controlling means associated with
said prime mover for controlling the operation
thereof, a control circuit including a control coil
for operating said controlling means and includ
ing a pair of control contacts, and a leveling re
lay including an armature carrying one of said
control contacts, including a contact arm carry
ing the other control contact, and including a
magnetic coil adapted upon being energized to
attract and hold said armature in position for
engagement of the control contact thereon with
the control contact on said contact arm, of an
energizing circuit including zone contacts and
said magnetic coil, a zone arm connected to said
car and adapted to close said zone contacts for
energization of said magnetic coil only when said
car is near said floor, and a limit arm connected
to and having a movement corresponding to the
movement of said car, for engaging said contact
arm to hold it and the control contact thereon in
position for contact with the control contact on
said armature upon energization of said magnetic
coil, and disengaging said contact arm to open
said contacts and said control circuit so that said
controlling means is operated to stop said prime
mover precisely when the car is level with said
floor.
2. In an automatic system for leveling an ele
vator car with respect to a floor, the combina
tion with a motor connected to said elevator car
60 and for moving the same with respect to said
floor, a motor circuit including motor contacts
and said motor, a motor control circuit including
a contactor for operating said motor contacts
and including a pair of motor control contacts,
and a leveling relay including an armature car
rying one of said motor control contacts, a con
tact arm carrying the other motor control con
tact, and including a magnetic coil adapted upon
being energized to attract and hold said arma
ture in position for engagement of the control
contact thereon with the control contact on said
contact arm, of an energizing circuit including
zone contacts and said magnetic coil, a zone arm
connected to said car and adapted to close said
7,5 zone contacts for energization of said coil only
when said car is near said floor, and a limit arm
connected to and having a movement corre
sponding to the movement of said car, for engag
ing said contact arm to hold the motor control
contact thereon in position for contact with the
other motor control contact upon energization of
said coil, and adapted to disengage said contact
arm and permit separation of said control con
tacts.
3. In an automatic system for leveling an ele
vator car with respect to a floor, the combina
10
tion with a motor connected to said elevator car
and for moving the same with respect to said
floor, a motor circuit including motor contacts
and said motor, a motor control circuit including 15
a contactor for operating said motor contacts
and including a pair of motor control contacts
and a leveling relay including an armature car
rying one of said motor control contacts and
normally in an inoperative position, a magnetic 20
coil adapted upon being energized to move said
armature to an operative position, and a contact
arm carrying the other motor control contact
and normally in an inoperative position irre
spective of the energization of said magnetic coil,
of an energizing circuit including zone contacts
and said magnetic coil, a zone arm connected to
said car and for closing said zone contacts to en
ergize said magnetic coil and attract said arma
ture only when said car is near said ?oor, and 30
a limit arm connected to said car to move at a
speed corresponding to car speed and for main
taining said contact arm in operative position
as said car approaches said floor whereby said
motor contacts are closed.
4. In an automatic system for leveling an ele
vator car with respect to a ?oor, the combination
with a motor connected to said elevator car and
for moving the same with respect to said floor, a
motor circuit including motor contacts and said 40
motor, a motor control circuit including a con
tactor for operating said motor contacts and in
cluding a pair of motor control contacts, and a
leveling relay including an armature carrying one
oi~ said motor control contacts, having an abut 45
ment and normally in an inoperative position, a
magnetic coil adapted upon being energized to
move said armature to operative position, and a
contact arm carrying the other motor control
contact and normally in an inoperative position 50
irrespective of the energization of said magnetic
coil, of an energizing circuit including zone con
tacts and said magnetic coil, a zone arm connect
ed to said car and for closing said zone contacts
to energize said magnetic coil and attract said 55
armature to operative position only when said car
is near said floor, and a limit arm connected to
said car to move at a speed corresponding to car
speed and for maintaining said contact arm in
operative position as said car approaches said 60
?oor, said abutment on the armature engaging
said contact arm normally to maintain the same
out of the path of said limit arm when said mag
netic coil is not energized.
5. In an automatic system for leveling eleva
tors, the combination with an elevator assembly
including a hatchway having a plurality of floors,
an elevator car movable within said hatchway,
and a prime mover connected to said elevator car
and for moving the same with respect to said 70
?oor, controlling means associated with said
prime mover for controlling the operation there
of, a control circuit including a control coil for
operating said controlling means and including a
plurality of pairs of control contacts, each corre- I‘
2,125,876
sponding to one of said floors, and a plurality of.
leveling relays each corresponding to one of said
floors and to one pair of control contacts and each
including an armature carrying one of the respec
tive pair of control contacts, a contact arm carry
ing the other control contact of said pair, and
each including a magnetic coil adapted upon be
ing energized to attract and hold said armature
in position for engagement of the control con
10 tact thereon with the control contact on said
contact arm, of a plurality of energizing circuits
each including a pair of zone contacts and the
magnetic coil of one of said leveling relays, a
plurality of zone arms connected to said car and
15 each adapted to close the corresponding zone
contacts for energization of the respective mag
netic coil only when said car is near ‘the corre
sponding ?oor, and a plurality of limit arms all
connected to said car to move at a speed corre
sponding to car speed, each for engaging the
corresponding contact arm of the respective
leveling relay to hold it and the contact thereon
in position for contact with the control contact
on the associated armature upon energization of
25 the corresponding magnetic coil, and each dis»
engaging the corresponding contact arm precise~
ly when the car is level with the respective floor
to permit disengagement of the control contacts
on the ‘energized leveling relay.
6. In an electro-mechanical automatic system
for leveling an elevator car with respect to a
floor, the combination with a motor connected
to said elevator car and for moving the same with
respect to said ?oor, and a leveling relay for each
floor and including a pair of normally open motor
control contacts, a contact arm carrying one of
said motor control contacts, an armature carry-
ing the other of said motor control contacts, and
a magnetic coil for attracting said armature to
close said motor contact, of an energizing circuit
connected to said magnetic coil and including a
pair of zone contacts, and a mechanical control
means connected to said elevator car, including
azone arm for closing said zone contacts only when
said car is adjacent to said ?oor to energize said
coil and close said motor control contacts, and in
cluding a limit arm moving at a speed correspond
ing to car speed for engaging said contact arm to
maintain said motor contacts closed as the car ap
proaches said floor and for permitting said motor
contacts to open just as the car becomes level
with said ?oor.
'7. In an automatic leveling system for ele~
vators, the combination with an elevator car
within a hatchway having a plurality of landings,
a motor connected to said elevator car and for
moving the same within said hatchway, a leveling
7
8. In a leveling system for elevators, the com
bination with an elevator car within a hatchway
with a plurality of landings, a reversible motor
connected to said elevator car and for moving the
same within said hatchway, and a leveling relay Cr
for each landing and including two pairs of nor
mally opened motor control contacts, a pair of
contact arms each carrying one of each pair of
said motor control contacts, a single armature
carrying both of the other of said pair of motor 10
control contacts, and a magnetic coil for attract
ing said armature to close said motor control con
tacts, of a plurality of holding circuits each con
nected to the magnetic coil of each leveling relay
and including a pair of zone contacts, an up
motor control circuit including one pair of motor
control contacts on said leveling relay, a down
motor control circuit including the other pair of
motor control contacts on said leveling relay, and
a mechanical control means connected to said ele
vator car, including a zone arm for closing said
zone contacts only when said car is adjacent to
the corresponding landing to energize said mag
netic coil and attract said armature, and includ
ing a pair of limit arms moving at a speed cor 2 2-)
responding to car speed and each for engaging
one of said contact arms alternatively, one of
said limit arms engaging the contact arm carrying
one of the motor control contacts in the up motor
control circuit to maintain said contacts closed 30'
while the car is moving upwardly toward said
landing, and the other of said limit arms engag
ing the other contact arm carrying one of the
motor control contacts in the down motor control
circuit to maintain said contact closed while the
car is moving downwardly to said landing, neither
of said limit arms engaging the respective con
tact arms when the car is level with the landing
in which position both pairs of contacts are nor
mally open.
9. In a leveling assembly for an elevator car,
the combination with a limit arm having the end
thereof moving with the elevator car and through
a distance corresponding to the travel of said
car, of a leveling relay comprising a contact arm .1 ,
movably mounted and located normally to as
sume a position in the path of and adapted to
bear against said limit arm, an armature mov
ably mounted norm-ally to assume an inopera
tive position, an abutment adjustably connected
to said armature and adapted during inoperative
position of said armature to engage said contact
arm and hold it out of the path of said limit
arm, and a magnetic coil positioned and adapted
upon being energized to move said armature into
operative position and for disengagement of said
relay for each landing and including two pairs of
abutment and said contact arm so that said
contact arm may move into the path of said
control contacts, two contact arms each carrying
limit arm.
60 one contact of each pair of control contacts, a
magnetic coil, and an armature carrying the
other contact of each pair of control contacts, a
mechanical control means connected to said ele
vator car, including a set of zone arms rotating
65 only once for each passage of said car through
said hatchway, and including a set of pairs of
limit arms rotating at a speed corresponding to
car speed, an energizing circuit connected to the
magnetic coil of each leveling relay and includ~
70 ing a pair of zone contacts which are closed by
the corresponding zone arm as the car approaches
a landing, and a motor control circuit including
said control contacts which are opened by the ap
propriate limit arm when a car is level with the
75 landing.
10. In a leveling assembly for an elevator car,
the combination with a limit arm having the end
thereof moving with the elevator car and through
a distance corresponding to the travel of said
car, of a leveling relay comprising a base mem
ber, a contact arm movably mounted thereon
and located normally to assume a position in the
path of and adapted to bear against said limit
arm, a stop on said base member and for limit
ing the normal movement of said contact arm
into the path of said limit arm, an armature 70
movably mounted on said base member normally
to assume an inoperative position and engaging
said contact arm to hold it out of the path of
said limit arm, and a magnetic coil positioned
and adapted upon being energizedto move said 75
8
2,125,876
armature into operative position, in which posi
tion said contact arm is free normally to move
into the path of said limit arm and into engage
ment with said stop which determines the ulti
mate position of said contact arm.
11. Ina leveling assembly for an elevator car,
the combination with a limit arm having the
end thereof moving with the elevator car and
through a distance corresponding to the travel
ll) of said car, of a leveling relay comprising a
base member, a contact arm movably mounted
thereon and located normally to assume a posi
tion in the path of and adapted to bear against
said limit arm, an varmature movably mounted
on said base member normally to assume an in
operative position and having an abutment en
gaging said contact arm to hold it out of the
path of said limit arm, and a stop on said base
member for engaging said contact arm to limit
the movement of said contact arm out of the
path of said limit arm by the abutment on said
armature.
12. In a leveling assembly for an elevator car,
the combination with a limit arm having the end
thereof moving with the elevator car and through
a distance corresponding to the movement of said
elevator car, of a leveling relay comprising a con
tact arm movably mounted and located normally
to assume a position with a portion of said contact
arm in the path of and adapted to bear against
the end of said limit arm, a contact on said con
tact arm, an armature movably mounted to as
sume an inoperative position, a second contact
adjustably mounted on said armature and for
engaging said contact on the aforementioned
contact arm, and a magnetic coil positioned and
adapted upon being energized to move said arma
ture and adjustable contact toward said contact
arm for closure of said contacts at a time deter
40 mined by the adjustment of said adjustable con
tact.
13. In an automatic system for leveling an
elevator car with respect to a ?oor, the combina
tion with a pair of limit arms having the ends
thereof moving with the elevator car and
through a distance corresponding to the move
ment of said elevator car, of a leveling relay com
prising a pair of contact arms movably mounted
and each located normally to assume a position
with a portion thereof in the path of and to
bear against the end of the respective limit arm,
a contact on each of said contact arms, an
armature movably mounted normally to assume
an inoperative position and having a pair of
parts for engaging respective contact arms and
adapted to hold each contact arm out of en
gagement with the respective limit arm, a pair of
contacts on said armature, and a magnetic coil
positioned and adapted upon being energized to
move said armature toward said contact arm,
said limit arms being relatively displaced, one of
said limit arms engaging one contact arm when
the elevator car is above said floor for closure
of the corresponding contact on the armature
and said one contact arm, and the other of said
limit arms engaging the other of said contact
arms when the elevator car is below said floor
for closure of the corresponding contact on the
armature and said other contact arm.
14. In an automatic system for leveling an ele
vator car with respect to a floor, the combina
tion with a pair of limit arms having their ends
angularly displaced and rotating through a dis
tance corresponding to the travel of said car, of
75 a leveling relay comprising a pair of contact arms
movably mounted and located normally to assume a position with each contact arm in the
path of and adapted to bear against one of said
limit arms, a contact on each contact arm, an
armature movably mounted, adapted normally to
assume an inoperative position and for holding
said contact arm out of the path of the respec
tive limit arm, a pair of contacts on said arma
ture, and a magnetic coil positioned and adapted
upon being energized to move said armature to
ward said cont-act arm and releasing said con
tact arm to permit normal movement thereof,
one of said limit arms engaging one of said con
tact arms when said elevator car is above said
floor to hold said one contact arm in position
for closure of the corresponding contact on the
armature and the engaged contact arm upon en
ergization of said coil, the other of said limit
arms alternatively engaging the other of said
contact arms when said elevator car is below said
?oor to hold the other said contact arm in posi
tion for closure of the corresponding contact on
the armature and the engaged contact arm dur
ing energization of said coil, and neither of said
limit arms being opposite said contact arms when
the elevator car is level with said floor to per
mit both of said cont-act arms to move to nor
mal inoperative positions to open simultaneously
in spite of the energization of said coil.
15. In a leveling assembly for an elevator car, ->
the combination with a limit arm having the end
thereof moving with the elevator car and through
a distance corresponding to the movement of
said elevator car, of a leveling relay comprising a
contact arm movably mounted and located nor
mally to assume a position with a portion of said
contact arm in the path and adapted to bear
against the end of said limit arm, a contact on
said contact arm, an armature movably mounted
normally to assume an inoperative position and
having a part for engaging said contact arm to
hold the same out of engagement with said limit
arm, a second contact on said armature, and a
magnetic coil positioned and adapted upon being
energized to move said armature toward said 45
contact arm for closure of the contacts thereon as
long as said contact arm bears against said limit
arm, said contacts being separated upon disen
gagement of said contact arm and said limit arm
even though said magnetic coil is energized.
16. In a leveling assembly for an elevator car,
the combination with a limit arm having the end
thereof moving with the elevator car and through
a distance corresponding to the travel of said car,
of a leveling relay comprising a contact arm mov
ably mounted and located normally to assume a
position in the path of and adapted to bear
against the end of said limit arm, a contact on
said contact arm, an armature movably mounted
normally to assume an inoperative position and 60
for engaging said contact arm to hold the same
out of the path of said limit arm, a second con
tact on said armature, a magnetic coil positioned
and adapted upon being energized to move said
armature toward said contact arm for closure of
the contacts thereon during engagement of said
contact arm and said limit arm, and a resilient
means between said armature and said contact
arm, tending to separate said arms and causing
separation of said contacts immediately upon
disengagement of said contact arm and said limit
arm.
17. In a leveling system for an elevator car
moving with respect to a landing, the combina
tion with a shaft connected to said elevator car,
2,125,876
9
a limit arm on said shaft and having its end
direction,~a second contact adjustably mounted
moving through a distance corresponding to the
travel of said elevator car, and an adjustable
connection between said shaft and said limit arm,
upon said armature and positioned so as to en
of a leveling relay comprising a contact arm
movably mounted and located normally to as
sume a position with said contact arm in the path
of and adapted to bear against said limit arm,
a contact on said contact arm, an armature mov
gage the contact on said contact arm when said
coil is energized, an abutment adjustably mounted
on said armature and for engaging said contact
arm to hold the same against one of said stops
during normal position of said armature, a spring
arm between said armature and said contact arm
and for normally separating the contacts thereon
inoperative position and having a part for en
gaging said contact arm to hold the same out of
but adapted to be overcome for engagement of 1O
said contacts upon energization of said electro
magnetic coil, and a limit arm for engaging the
engagement with said limit arm, a second con
roller on said contact arm‘ to hold the contact on
tact upon said armature, and a magnetic coil
said contact arm in position for engagement with
the other contact upon energization of said coil.
10 ably mounted and adapted normally to assume an
positioned and adapted upon being energized to
move said armature toward said contact arm for
closure of the contacts thereon during engage
ment of said contact arm and said limit arm, said
contacts being separated, even though said coil
is energized, upon disengagement of said contact
arm and said limit arm, the moment of said dis
engagement being variable to take place precisely
when the car is level with said landing by adjust
ment of the limit arm with respect to said shaft.
18. In an electro-mechanical relay, the combi
25
nation with a base, an electro-magnetic coil
mounted upon said base, an armature pivoted on
said base normally to swing away from said coil
but adapted to be attracted toward said coil
upon energization thereof, a contact arm carry
ing a contact on one end and a roller on the other
end thereof and intermediately pivoted to said
base, a pair of stops adjustably mounted upon
said base, one to limit the rotation of said con
35 tact arm in one direction and the other to limit
the rotation of said contact arm in the opposite
19. In an electro-mechanical relay, the com
bination with a support, a contact arm carrying a
contact and movable to a contacting position,
a magnetic arm also carrying a contact, normally
in an inoperative position and movable to an ener
gized position, a resilient means between said
magnetic arm and said contact arm‘ for sepa
rating the same and the contacts thereon, a con
trol member for engaging said ‘contact arm and
moving the same to contacting position, and a
coil adjacent said magnetic arm and adapted
upon being energized to move said magnetic arm
to energized position and to move the contact
thereon into contact with the contact on said con
tact arm, said resilient means being adapted upon 30
disengagement of said control member and said
contact arm to separate the contacts on said
magnetic and control arms even though said coil
is still energized.
JAMES H. BARTHOLOMEW.
35
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