Dec. 17, 1963
|_. L. TANGUY, JR
3,114,902
ITEM TRANSPORT MONITORING SYSTEM
Filed Dec. 24, 1959
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INVENTOR
LEWIS L. TANGUY,JR.
BY
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ATTORNEY
Dec. 17, 1963
14,902
L. L. TANGUY, JR
ITEM TRANSPORT MONITORING SYSTEM
Filed Dec. 24. 1959
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Dec. 17, 1963
L. L. TANGUY, JR
3,114,902
ITEM TRANSPORT MONITORING SYSTEM
Filed Dec. 24. 1959
6 Sheets-Sheet 3
Dec. 17, 1963
L. |_. TANGUY, JR
3,114,902
ITEM TRANSPORT MONITORING SYSTEM
Filed Dec. 24. 1959
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LEWIS L. TANGUY,JR.
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ATTORNEY
Dec. 17, 1963
I_. L. TANGUY, JR
3,114,902
ITEM TRANSPORT MONITORING ‘SYSTEM
Filed D80. 24, 1959
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LEWIS L. TANGUY,JR.
BY
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ATTORNEY
United States Patent 0
I
3,114,9(92
ITEM TRANSPGRT MQNHTORWG SYSTEM
Lewis L. Tanguy, .lr., Phoenixville, Pa., assignor to Bur
roughs Corporation, Detroit, Mich, a corporation of
Michigan
Fiied Dec. 24, E59, Ser. No. 861,963
10 Claims. (Ci. 340—25§)
3,114,902
Patented Dec. 17, 1963
2
departure of an item can be detected and appropriate
signals can be produced therefor.
In accordance with another primary feature of the pres
ent invention there is provided a plurality of sets of timing
circuits and detecting circuits with each set assigned and
coupled to a different one of the stations mentioned above,
and with each detecting circuit further coupled to the
station subsequent to its assigned station. Each timing
This invention relates to automatic item transport sys
tems, and more particularly to a monitoring arrangement 10 circuit delays a signal from its assigned station for a pre
determined time which has a relationship to the time that
for detecting the movement of items transported by such
it
takes an item moving at a preferred speed to travel
a system and for providing signals signifying whether or
not the system is properly operating.
When work is performed on items in an automatic
from the assigned station to the subsequent station. Each
detecting circuit detects if a signal from the- subsequent
process, it is often necessary to transport the items along 15 station occurs within the predetermined time and provides
a signal if there is a failure of such subsequent station
a path through many stations where the work is per
signal occurrence within the predetermined time.
formed. At each of the stations the item is subjected to
The foregoing and other objects and features of this
certain physical and/or analytical operations, and it is
invention
will be best understood by reference to the fol
then moved on to the next station. For instance, when
lowing
description
of an embodiment of the invention
bank checks and deposit slips are fed through a bank 20
taken in conjunction with the accompanying drawings,
check sorter device, these checks have pre-printed or
wherein
punched information read from them (an analytical op
FIG. 1 is a schematic diagram of the item transport
eration) at one station; have additional information trans
path in a bank check sorter system;
ferred to them at a printing station (a physical operation);
FIG. 2 is a block diagram of the electrical circuitry
and are directed to a particular receiving pocket (another
without circuit details;
physical operation) at yet another station. Another ex
FIGS. 3a and 3b together represent a block diagram
ample of an item transport arrangement is found in the
of the system in detail; and
manufacture of certain airplane motors where a rough
FIGS. 4a and 4b are schematic diagrams of delay multi
casting is inserted in the system and is then automatically
vibrator
circuits;
transported through a number of operating stations for
FIGS.
5a and 5b are respectively a schematic diagram
grinding, milling, waxing, etc. The item which started as
of a beam-of-light circuit and a waveform of a signal;
a rough casting emerges from the automatic manufac
FIG. 6 shows the relationship of FIGS. 3a and 3b to
turing process as a ?nished cylinder.
each other.
In such item transport arrangements, especially if they
In FIG. 1 there is shown a schematic diagram of an
item transport system used in a bank check sorting device.
The invention will be described in connection w'th the
item transport system of a bank check sorter, but it should
be understood that the invention can be used effectively
with any item transport arrangement such as those which
to the items.
40
are employed in automatic manufacturing processes.
With regard to the “necessary” monitoring operations,
Consider ?rst the over-all operation of the bank check
?rst, the system should recognize when there has been a
sorter as shown in FIG. 1. The items 11, which are checks
failure to feed an item into the system. Such a failure
in our example, are held in a hopper 13 from whence they
in all probability would signify an empty input station
are fed into the system at the insert point 15 by a friction
(input hopper), or conceivably a jam at the input station.
feed device. As the input belt 17, which is driven by
Secondly, the system should recognize when the items are
wheels 19 which in turn are driven by motor 27, moves in
moving at a speed through the item transport path which
contact
with the checks they are fed, or driven by fric
is substantially different from the rated item speed of the
tion. The novel feeding of checks into this system is
system. Such an irregular transport of items might indi
described and claimed in the co-pending application en~
cate a jam has occurred or could lead to jams thereby
are high speed systems, at least two basic monitoring op
erations are deemed necessary while other monitoring
operations may be considered optional in order to insure
that the movement of the items is being carried on prop
erly and in order to prevent jams which result in damage
damaging the items. In another instance such impro
priety in item transport might signify some type of slipping
of the items being transported along the path.
As to the optional category it is often desirable to
recognize if any of the items is oversized, and in another
instance it is often desirable to know whether or not the
items are following one another too closely and are
therefore underspaced with respect to one another.
It is an object of the present invention to provide an
titled “Sheet Stack Advance Mechanism” by Misbin et al.,
Serial No. 772,552, ?led November 7, 1958, now Patent
No. 3,032,339, and which is assigned to Burroughs Cor
poration.
The checks, after leaving the hopper, are moved along
the entire transport path 21 to the chute blades 23. In
accordance with the information read from each check
a chute blade is selected for each check to guide it to the
proper stacker pocket. Only a small number of the
stacker pockets are shown in FIG. 1.
The checks are
improved item transport monitoring system.
driven through the entire transport path by a series of
It is a further object of the present invention to provide
an item transport monitoring system which detects the
speed of an item between two points along the item trans
drive rollers which are driven by motors 25, 27 and 29.
port path.
At various points along the transport path 21 there are
found beam-of-light stations (BOL-a through BOL—g),
located to sense the entry and departure of a check, and
It is a further object of the present invention to provide 65 in response thereto produce appropriate signals. If the
checks are detected as travelling improperly, for‘ instance
an item transport monitoring system which detects when
slower than they should be, the monitoring system gen
there has been a failure to feed an item into the item
erates a signal which is transmitted to stop the motors 25,
insert location of the path.
In accordance with a primary feature of the present 70 27 and 29 in order to prevent driving additional items
along the path. The system philosophy is that by stopping
invention there is provided a plurality of stations along
any further movement of items when an irregular trans
the path of item transport. At each station the entry and
port condition is detected, possible jam conditions, which
3,114,902
3
normally result from irregular item feeding and move
ment, will be prevented before they actually happen.
Further, if a jam has occurred, the termination of item
movement will prevent damage to items which may be
driven into the jammed items.
In the bank check sorting system we are herein consid
ering the items leaving the hopper 13 are travelling at a
speed of 150 inches per second. Their speed is increased
4
in an interim storage means.
This same feeder clutch
signal is simultaneously passed through the signal delay
means 43. As was suggested earlier, the signal delay
means 43 will delay this ?rst station signal for a period
of time which is slightly longer than the time it should
take for an item moving at the preferred speed (150
inches per second) to travel from the input point 15 to
the BOL-a station 37. The coincidence device 45, whose
role will become better understood hereinafter, is con
with the burst roller 31, and they continue to travel at 10 nected to receive the output signls from ?ip-?op 41 when
it is in its set condition and from the signal delay means
400 inches per second throughout the system. Further,
43. The coincidence 45 may be any well-known AND
in the bank check sorting system under consideration here
gate, and as is understood in electronic circuit design
certain information found on the checks is read at the read
when a coincidence device is fully conditioned, it pro
head station 33. The information read at 33 is processed
vides in response an output signal.
and eventually provides for the selection of the proper one
In accordance with the earlier discussion relating to
of the chute blades 23. The operation of the reading sys
the comparison between a delayed ?rst station signal and
tem and the selection of the chute blades are respectively
an undelayed second station signal to determine whether
described and claimed in co-pending US. patent applica
to 400 inches per second when the items come in contact
tions entitled “Voltage Comparison Circuit” by Shaeffer
or not an item is moving between two stations at a pre
et al., Serial No. 789,983, ?led January 29, 1959, and 20 ferred speed, we must examine the transmission of the
second station signal, Ta. The Ta signal is transmitted
“Item Handling Apparatus” by Hanstein et 211., Serial No.
directly along line 49 ‘to place ?ip-?op 41 in its reset
837,004, ?led August 31, 1959, and now abandoned, both
condition. The coincidence device 45 and the ?ip-?op 41
of which are assigned to the Burroughs Corporation.
act together to perform the comparison between the
'For a better understanding of the invention and the de
tailed description thereof which is to follow, consider in 25 delayed feeder clutch signal and the undelayed Ta sig
nal. It becomes evident in FIG. 2 that if the ?ip-?op 41
this regard the general operation of a pair of monitoring
is not reset by a Ta signal before the delayed feeder
stations in connection with an item travelling therebe
clutch signal reaches the coincidence device 45, there will
tween. If an item is travelling between two stations at
be an alarm signal produced on line 47 since coincidence
a preferred speed and the distance between the two sta
tions is ?xed, and further, if the distance is divided by 30 device 45 will be fully conditioned by the output signals
the speed, the time that the item should take to travel
this ?xed distance is known or predetermined. The mon
from flip-flop 41 and the signal delay means 43.
In essence, then, by permitting the Ta signal to erase
actually moves from one station to the next within this
the stored ?rst station or feeder clutch signal and there
by prevent the coincidence device 45 from becoming
fully conditioned or in the alternative by permitting the
predetermined time. As will become evident hereinafter,
delayed feeder clutch signal to fully condition the coin
itoring system of the present invention operates to detect
whether or not an item travelling between two stations
the detection of whether or not the item has arrived at
the second station within the predetermined time is ac
cidence device 45 if such erasure does not take place, the
complished (using the trailing edge signal as a reference)
coincidence device 45 acts with the ?ip-?op 41 as a com
paring means to compare the arrival times between a
at the preferred speed, by further generating a signal
When this operation is considered in particular with
by generating a signal when an item has departed from a 40 delayed ?rst station signal and undelayed second station
signal. ‘If the delayed ?rst station signal arrives ?rst in
?rst monitoring station, by then delaying this signal for
time, then the item is recognized as travelling too slowly
an amount of time which is slightly longer than the time
and an alarm signal is generated.
it would take the item to travel between the two‘ stations
when the item has departed from the second station, and 45 the feeder clutch signal and the Ta signal, we ?nd that if
by ?nally transmitting the delayed ?rst station signal and
no item is fed into the system or if the item never passes
the undelayed second station signal to a comparing de
vice. Obviously if the item has not departed from the
BOL-a station 37 there will be no Ta pulse emanating
second station thereby not generating its signal before the
delayed signal from the ?rst station (remembering that
signal produced on line 47 indicating that either there
from source ‘38 and therefore there will be an alarm
50 has been no item fed or there has been an irregular item
station) arrives at the comparing device, the comparing
device should recognize that the item is travelling slower
than the preferred speed.
transport between the input point 15 and the station 37.
We can summarize then that the feeder clutch signal and
a trailing edge signal from the BOL-a station 37 operate
together in conjunction with the signal delay means 43,
flip-flop 41 and coincidence device 45 to detect whether
For a more detailed study, consider now FIG. 2 in
or not an item has been fed into the system and/or
it has been delayed for more than the amount of time
that it should have taken the item to get to the second
whether or not an item is travelling at its rated speed
conjunction with FIG. 1. FIG. 2 is a general block dia
between input point 15 and station 37.
gram of the system. When the system is turned on and
Further, assume that an item has been properly fed
the start device activated (either manually or by aux
and has passed station 37 at its rated speed; has been
iliary equipment), there is a signal from the feeder clutch
accelerated by burst roller 31; and has passed the BOL-b
signal source 35. Such a feeder clutch signal energizes
station 51. Examining FIG. 2 we ?nd that the trailing
the feeder clutch (not shown) which in turn engages the
edge signal Ta emanating from source 38 works in con
motors 25, 27 and 29 of FIG. 1, which in turn drives
junction with a ‘trailing edge signal Tb emanating from
the input belt 17 and the drive rollers to move the checks
from the hopper past the roller 19- and past the BOL-a 65 source 53. The Ta signal which passes along line 49‘ to
reset ?ip-flop 41 simultaneously sets ?ip-?op 55. This
station 37. When a check departs from the BOL-a sta
tion 37 -a trailing edge (Ta) signal is generated by signal
Ta signal in addition is simultaneously passed through
the signal delay means 57. The operation is virtually
Initially examine the function of the two signals (the
identical to the operation of the feeder clutch signal and
feeder clutch signal and the Ta signal) which have been 70 the Ta signal described above. In other Words, if ?ip
generated as described above. The feeder clutch signal,
?op 55 is in its set condition thereby providing an output
source 38, FIG. 2.
which can be considered the ?rst station signal, is trans
mitted directly by wire 39 to place the ?ip-?op 41 in its
set condition. This signi?es that the item has departed
from the ?rst station and its departure has been recorded
signal, at the time that there is an output signal from
the signal delay means 57, these two output signals will
fully condition the coincidence device 59 to generate an
3,114,902
alarm signal on line 61. However, such an alarm signal
may be prevented if, in fact, the trailing edge pulse from
Tb source 53 is transmitted along the line 63 to reset ?ip
?op 55 before the Ta pulse is transmitted from the delay
means 57. This last-described ‘operation differs from the
?rst (feeder clutch signal——Ta signal) described opera
tion only in that the delay of the Ta signal effected by the
signal delay means 57 in all probability will be different
from the delay of the feeder clutch signal effected by the
signal delay means 43. The respective delay times of
the signal delay means 43 and 57 will depend upon the
distance between the associated BOL stations and the
rated speed of the items in transport between the stations.
It becomes clear that a Ta pulse from source 38 and a Tb
pulse from source 53 work in conjunction with signal
delay means 57, flip-flop 55 and coincidence device 59 to
detect if an item passing between the BOL-a station 37
and the BOL-b station 51 is travelling at the preferred
speed.
As can be seen in FIG. 1, as the items travel along the
6
between the BOL-f station 107 and BOL-g station 111 in
FIG. 1. It is further evident that the Lg pulse from
source 109 works in combination with Tg pulse from
source 113 to monitor the transport of an item through
the station BOL-g.
Throughout the description there has been and will
be reference made repeatedly to an AND gate and to
an OR gate. The ground rule to be followed in under
standing the present description, in view of the particular
10 AND gates and OR gates used, is in essence: each AND
gate requires positive input signals simultaneously ap
plied to each of its input leads to fully condition the
AND gate which in response provides a negative voltage
output. When an AND gate is not fully conditioned it
is providing a positive voltage output. Each OR gate
requires that at least one of its input lines be: conditioned
negative to provide a positive output signal. When none
of the input leads to an OR gate is negative its output is
negative.
item transport path 21, past the station 51, they continue
Such an electronic gating device is described in the
operate in conjunction with the signal delay means 71,
?ip-?op 73 and coincidence device 75 to detect whether
With respect to the references to ?ip-?ops throughout
the present description it is to be understood that a ?ip
co-pending application entitled “Switching Networks,” by
to move past the BOL-c station 65 and past the BOL-d
oward E. Tompkins, Serial No. 612,848, ?led September
station 67. At the BOL-c station 65 there is generated a
28, 1956. It should be understood, however, that other
To pulse, and at the BOL—d station 67 there is generated
a Td pulse. in FIG. 2 it becomes evident that the Tb 25 types of AND and OR gates may be used provided the
auxiliary circuitry used therewith is correctly provided.
pulse from source 53, and the Tc pulse from source 69',
or not an item passing between the station 51 and sta
tion 65 in FIG. 1 is travelling at its rated speed. The
operation of this last-mentioned circuit, which may pro
vide an alarm signal on line 77, is virtually identical to
the operation of the circuit described above in connec
tion with the Ta and Tb pulses excepting for a possible
difference in the signal delay times.
Similarly the Ta’ pulse from source 79 and the Tc pulse
from source 69 operate in conjunction with the signal
delay means 81, flip-?op 83 and coincidence device 85
?op herein may be any wellknown bistable multivibrator.
When a ?ip-flop has been placed (set or reset) in a
particular condition the ?ip-?op will provide a positive
voltage output from the terminal corresponding to that
condition while providing a negative voltage output sig
nal from the terminal corresponding to the other condi
tion.
FIG. 3 shows a detailed block diagram of the monitor
ing system not including optional equipment. When the
system is turned on all of the ?ip-?ops are placed in their
respective reset conditions. The feeder clutch signal
to provide an alarm signal on line 87 when there has been
an irregular item transport between stations 65 and 67 40 source 35 provides a signal with which the feed mech
anism is started. This feeder clutch signal is transmitted
of FIG. 1. The delay means 71 and 81 are designed to
along three paths, ?rst along the line 115 to the AND
delay the respective input signals thereto inaccordance with
gate 45; second, along the line 119 to the pulse standard
the rated speed of the items, and the distance between the
izer 121; and third, directly to AND gate 123.
stations whose signals these respective delay means are
The feeder clutch signal is a DC. signal, or a constant
assigned to handle.
45 voltage condition as contrasted by comparison with a
For design reasons the bank check sorter with which
pulse type signal. First consider the application of the
the present invention is described, switched from a trail
feeder clutch signal to the pulse standardizer 121. The
ing edge reference to a leading edge reference at station
pulse standardizer circuit may be any well-known R-C
BOL-c. It is to be understood at this point that the
circuit which responds to an initial voltage shift and pro
system could operate entirely with a trailing edge refer
vides a standard pulse in response thereto. A speci?c
ence or entirely with a leading edge reference, or any
example of a pulse standardizer is described hereinafter
combination of intermixed references as may suit the
in connection with FIG. 4. When the feeder clutch sig
needs of the system. At the BOL~d station 67 there is
nal is applied to pulse standardizer 121 there is trans
generated an Ld pulse which is so labeled in order to
mitted therefrom a negative pulse signal on line 125 to
designate a leading edge pulse generated at the BOL-d 55 the
OR gate 127.
station 67. The Ld pulse from source 89 in FIG. 2 is
According
to the ground rule previously stated, OR
directly transmitted to set ?ip-flop 91 and simultaneously
gate 127 accepts the negative pulse on line 125 and
transmitted through the signal delay means 93. As was
transmits a positive pulse on line 129 to the AND gate
described in connection with the circuits above, if the
131. Connected to AND gate 131 by line 133 is a “not
?ip-?op $1 is in its set condition providing an output there
disabled feeder” signal source 135. Optional equipment
from, at the time that there is an output signal from the
or auxiliary equipment, not shown in FIG. 3, may pro
signal delay means 93, these two output signals will fully
vide a negative signal on line 133 when it is necessary
condition the coincidence device 95 to produce an alarm
to temporarily terminate a recirculation of a Ta signal.
output signal on line 97. The alarm signal on line 97 can
For instance, optional equipment described and claimed
be prevented if, in fact, the Le pulse from source 99 (from
in co-pending application entitled “Monitoring System”
BOL-e station 181 in FIG. 1) is transmitted via line
by John Pedersen, ?led December 24, 1959, Serial No.
183 to reset ?op-flop 91 prior in time or before there is
861,828, now US. Patent No. 3,046,538, will detect when
an output signal from the signal delay means 93.
two items are underspaced or an item is overlength. Such
A further examination of FIG. 2 readily reveals that
an underspaced condition will give rise to a “disabled
the BOL-e pulse from source 99 works in combination
feeder” signal, or negative signal, from source 135 on
with the BOL-f pulse from source 185 to monitor the
line 133 to AND gate 131. If there is no condition
item transport between the BOL-e station 101 and BOL—f
warranting the “disabled feeder” signal a positive voltage
station 107 in FIG. 1. It is also evident in FIG. 2 that the
will appear on line 133. This last-mentioned positive
L1‘ pulse from source 105 works in combination with the Lg
voltage condition, in conjunction with the previously men
pulse from source 189 to monitor the item transport be
tioned positive voltage pulse on line 129, fully conditions
3,114,902
7
AND gate 131 to provide a negative output pulse there
from.
The negative pulse from the AND gate 131 is trans—
mitted to set ?ip-?op 41 and is simultaneously trans
mitted to OR gate 139. In response to this negative pulse
at OR gate 139 there is provided a positive output on
line 141 which is inverted by inverter 143 to become a
negative input signal on line 145 to the delay multi
vibrator 147. As will be more fully explained herein
8
the jam signal from being generated if in fact items are
‘progressing along the item transport at their rated speed.
When an item [has passed through the BOL-a station
37 in FIG. 1, there is provided a positive Ta pulse from
source '38 in ‘FIG. 3. The inhibiting role of a Ta pulse
is predicated on an acceptable Ta signal being generated
at BOL—a station 37. In the particular system under con
sideration it was felt that there should be some assurance
that a “good” Ta pulse had been generated. There are
conditions present in the feeding operation which
after in connection with FIG. 4 the delay multivibrator 10 some
might impede the provision of a “good” Ta pulse, al
is basically a monostable multivibrator which responds
though these possibilities have empirically been found
to a negative pulse and provides a negative voltage out
to be remote.
put for a predetermined time thereafter, and a positive
The Ta signal from source 318 is transmitted to the
voltage shift at the end of this predetermined time. The
standardizer 191, which in turn provides a negative
predetermined time for the delay multivibrator is slightly 15 pulse
output pulse to the delay multivibrator 193‘ and simul
longer than the time it should take an item which is
taneously to the delay circuit 195. The delay multivi
travelling at the preferred speed to travel from the input
point through BOL-a station 37. The negative voltage
condition appearing on line 149 for the predetermined
bratolr 1193 responds to a negative pulse of a predeter
mined amplitude and provides a negative output signal
therefrom (labelled gate) for a predetermined time.
time is inverted at inverter 151 to provide a positive
If the delay multivibrator 193 is not responsive to a Ta
voltage condition on line 153 for the predetermined time.
pulse there will be provided a positive voltage output
The positive voltage condition on line 153 is fed back
signal therefrom.
to the OR gate 155 causing this OR gate to transmit a
Assume that there is a Ta pulse of sufficient amplitude
negative voltage condition on line 157 for the delay time
to activate the delay circuit ‘195 but not of su?icient
of the multivibrator 147. Although the gate 155 is labeled 25 amplitude to activate the delay multivibrator 193. The
an OR gate, it is interesting to note that since line 156
weak Ta pulse would be transmitted through the delay
must stand by high for this last-described feed back to
line 195 to be inverted at the inverter ‘21111 and would
occur, gate 155 can be considered an AND gate in this
operation. The negative voltage condition on line 157
conditions the OR gate 139 to provide a positive voltage
condition on line 141 which again is inverted by inverter
143 to provide a negative input voltage on line 145. At
the end of the predetermined time (delay time of multi
vibrator 147) there will be transmitted on line 14‘) a
positive voltage shift which by virtue of the feedback
loop just described will terminate the negative input signal
on line 145.
This positive voltage shift being inverted at inverter
15‘1 becomes a negative signal, and being again inverted
at inverter 1159* becomes a positive signal which is trans
mitted to the pulse standardizer 161. The pulse stand
ardizer 1611 responds to a positive voltage shift to provide
provide a positive voltage signal on input line 203 to
AND gate 259.
Since delay mu1tivibrator-19'3 was not
responsive there would be a positive signal therefrom
which when inverted at inverter 2617 would provide a
negative signal at AND gate 269'. The negative signal
would not permit AND gate 2.119 to provide an output
to reset ?ipdlop 41. Therefore the output from the set
side of ?ip-flop 41 would set ?ip-?op 175, and as de
scribed before, provide a jam signal.
‘Now consider what happens when there is provided
an acceptabiie Ta pulse from the pulse standardizer 191.
40 In response to this. acceptable Ta pulse the multivibrator
1'93 provides a negative voltage output signal for a pre
determined time. The negative pulse from delay multi
vibrator 193, after being inverted at inverter 207 renders
a negative output pulse on line .163‘ which is inverted by
(along with the previously described positive signal from
inverter 1615 to provide a positive input pulse on line 169
inverter 2111), the AND gate 259 fully conditioned. The
to the AND gate ‘45. It should be recalled at this point
negative output from AND gate 213*?‘ is transmitted along
that ?ip-?op 41 was placed in its set condition which pro
line 2111 to reset ?ip-?op 41. It will be recalled that the
vides a positive voltage condition on the input line 171
positive voltage signal from the flip-flop 41, being in its
to ANDv gate 45 and that the positive feeder clutch signal
set condition, was necessary in order to render AND gate
was directly transmit-ted by line 11-5 to the AND gate 45.
45 fully conditioned, and the output ‘from AND gate 45
The three positive voltage conditions at the input lines of
in turn through ?ip-?op 175, driver 1'77, energized relay
AND gate 45 render that AND gate fully conditioned,
179 to open contacts 181 as described above, thereby
thereby providing a negative pulse signal on line 173
providing a jam signal on line ‘1831. In other words, when
to set ?ip-?op 175. The pulse on line .173 has a duration
?ip-?op 41 is reset the AND gate 45 is prevented from
of the pulse on line 169.
being fully conditioned. tl‘herefore, if the delayed pulse
When ?ip-flop 175 is placed in its set condition the 55 which eventually appears on line 1619‘, which is an input
negative level from its reset terminal is transmitted along
line to AND gate 45, arrives after Ta and attempts to
line 5176‘ through the OR gate 185 to the inverter 187 to
fully condition this AND gate, this attempt will be in
initiate a jam signal at ‘terminal 189. Simultaneously the
vain. This operation, while more detailed, is identical
signal from the set terminal of flip-flop 175 through the
to the operation discussed in connection with FIG. 2,
driver ‘177 energizes the latching relay 179 to open the 60 and particularly in connection with ?ip-?op 41 and coinci
relay contact points 181. Relay 17%, along with relays
182 and 11-84, is a ilatchingqtype relay to provide a sus
tained jam memory if the power is turned OFF before
having cleared a jam and the power is subsequently turned
dence device 45.
It will be recalled that the feeder clutch signal from
source 35 is a constant voltage signal or DC signal.
The comparison between stations is based on a compari
on again. When the relay contacts 181 are opened a 65 son of properly timed pulses and therefore it is desirable
negative signal is transmitted on line 183 through the
to develop pulse-type signals ‘from the feeder clutch sig
OR gate 185 through the inverter 187 to aid in provid
nal, or provide pulses controlled by the feeder clutch
ing a jam signal at terminal 189. The jam signal in the
signal, if there is to be a comparison between a feeder
bank check sorter system is used to terminate the motor
operation but this signal can be used to merely warn the 70 cil‘u’tch signal and a Ta pulse from source 33. As was ex
plained before, a pulse-type signal is generated at the
operator by virtue of a light or a buzzer. Obviously, and
pulse standardizer 121 in response to the positive change
in accordance with our discussion in connection with FIG.
of voltage at the input when the operation is initially
2, it would not be desirable to provide a jam signal every
started. Thereafter this pulse is directed through the
time the feeder clutch was energized. Consider then the
circuitry as described earlier in order to provide a com
operation of the Ta pulse from source 38 which prevents
9
3,114,902
10
parison (in time) with a Ta pulse. The DC signal
from source 35, when the system is operating “free ?ow"
as compared with “demand,” does not provide a pulse
for each item subsequent to the ?rst for comparison, and
in order to do so, a Ta pulse is circuitry—rou-ted (recircu
lated) and controlled by the feeder clutch signal to pro
vide a pulse representing an item in transport at the item
input station.
When the Ta pulse is generated at source 38 it is trans
on line 233 is applied to AND gate 59. This operation
has been described above in connection with FIG. 2, and
especially in the description of the operation of ?ip-?op
5
55 and coincidence device 59.
The signal delay means 227 and 229 are split as shown
in order to provide a storage for a subsequent item in the
delay multivibrator 227 while in fact the system is op
erating or comparing a delayed signal from a previous
item being transmitted from delay multivibrator 229.
mitted through the pulse standardizer 191 to delay multi
The signal from Tb source 53 operates in conjunction
vibrator $193. The output from delay multivibrator 193 10
is transmitted along two paths, one of which has been
with the Tc signal from source 69 in a fashion virtually
identical to the operation between the Ta and Tb pulse
previously described, i.e., to inverter 2&7. The negative
output signal ‘from the delay multivibrator 193 is trans
just described. In other words, a Tb pulse passing through
a positive delayed (Ta) output on line 1249 to serve as an
tween the Tc pulse with the Td pulse, are transmitted to
set ?ip-?op 245 and the jam signal which ensues is as
delay multivibrator 257 and delay multivibrator 259 and
mitted along the second path to inverter 2113 where it
becomes a positive pulse. This positive pulse from in— 15 inverter 261 attempts to fully condition the AND gate
75 before a TC‘ pulse from source 69 transmitted along
verter 2413 is then transmitted along the line 215 to AND
line 263 resets flip-?op 73. Similarly a Tc pulse from
gate 123. For the purpose of explanation at this point,
source 69 is transmitted through delay multivibrator 265,
consider that there is a positive voltage on the “not
the delay multivibrator 267 and the inverter 269 and
demand” line 217. These three positive signals, i.e., the
feeder clutch signal, the “not demand” signal and the out 20 attempts to fully condition the AND gate 85 before a Td
pulse from source 79 transmitted along line 273 resets
put from inverter 213 fully condition the AND gate 12-3
the flip-flop 83. The output signals from a comparison
to provide a negative signal on line 219. The negative
between the Tb and the Tc pulse, and a comparison be
signal on line 219‘ conditions the OR gate 127 to provide
operative substitute for the feeder clutch signal.
The positive pulse on line 129 along with the positive
D.C. level on line 133 fully conditions the AND gate
131 to provide an output pulse which performs the same
role as did the output pulse from the pulse standardizer
121, as previously described. If the feeder clutch signal
is not supplied to the AND gate 123 the Ta pulse will not
be transmitted the'rethrough. Such a feeder clutch signal
control arrangement effectively provides a pulse from the
item insert point to be used for comparison with a Ta
pulse subsequently generated.
described before.
As was suggested earlier, in the bank sorter system
which we are considering here, it was desirable for design
purposes to switch to a leading edge reference at the
B0141 station. The leading edge signal Ld from source
89 is transmitted through the delay multivibrator 277, the
inverter 279 in an attempt to fully condition the AND
gate 95 before the leading edge pulse Le from source 99
is transmitted on line 281 to reset the ?ip-?op 91. Simi~
larly a leading edge signal Lf from source 195 is com
pared with a delayed leading edge signal Le from source
99, and the leading edge signal Lg from source 109 is
compared with the delayed L7‘ signal from source 105.
the feeder clutch signal 35 to the pulse standardizer 121;
a comparison (in time) of this initial pulse with a subse 40 When the item is passed through the last station, the
BOL-g station, the system is slightly varied. Since there
quent station pulse from station BOL-a to detect whether
In summation, thus far we have examined the genera
tion of a pulse when the system is turned ON by virtue of
or not items are being properly transported between the
insert point and the BOL-a station; the generation of a
jam signal it this last-mentioned comparison fails to ?nd
Ta occurring prior in time to the delayed initial pulse;
is no advanced station with which a signal from this sta
tion could be compared, the item is merely monitored by
comparing its leading edge pulse with its trailing edge
pulse. This can be seen by considering that an Lg pulse
and a recirculation of the (Ta) pulse to provide a pulse 45 from source 199 is delayed by the delay multivibrator
291 which subsequently attempts to fully condition the
representation for an item subsequently being transported
AND gate 293 before the Tg pulse from source 113 re
into the insert station.
sets ?ip-flop 295.
To carry on further, and in accordance with the previous
In connection with the comparison between the L)‘ pulse
discussion of FIG. 2, we know that the Ta pulse from
and the Lg pulse there is also a slightly varied arrange
source 38 will be compared with the Tb pulse from source
ment. The L]‘ pulse from source 105 is initially trans
53. The Ta pulse from source 38, after it leaves the
mitted to the AND gate 283 whose other input line is
AND gate 2G9, is transmitted along line 223 to inverter
connected to a “not demand” signal. It will be noted
225 to provide a positive pulse from inverter 225 which
that the BOL-f station as seen in FIG. 1 is near the end
is transmitted to the delay multivibrator 227. The output
from delay multivibrator 227 is transmitted along two 55 of the transport path or near the entry to the chute blades.
In one of the operations with which the bank sorter sys
paths, the ?rst of which is to the delay multivibrator 229.
tem is used, it is possible to pass a single item through
The output from the delay mulitvibrator 229 is inverted
the system. When this happens the status is considered as
at inverter 231 and transmitted on line 233 to the AND
“demand.” In a “demand” operation the item is trans
gate 59. The second path along which the output from
delay multivibrator 227 is passed is along line 237 to 60 ported to a stand-by station 284 whereat the item is
stopped. At some later time the item is transported from
set ?ip-?op 239. The output from the set condition ter
the stand-by station to the chute blades 23. So long as
minal of ?ip-?op 239 is transmitted via line 241 to fully
the status is “not demand” or is a “free flow” of items,
condition (along with the signal on line 233) and AND
there is provided a positive signal on line 285‘ and line
gate 59. When the AND gate 59 has been fully condi
tioned its output signal is transmitted along line 243 to 65 287. If in fact a single item is being processed a “demand”
signal or a negative signal will appear on line 285 and
set ?ip-‘lop 245, and the output therefrom through the
driver 247 energizes relay 132. The negative signal on
line 251 from the reset terminal of ?ip-?op 245 to the OR
line 237 respectively, disenabling gates 283 and 289.
The philosophy for this arrangement is twofold. First,
if the item is stopped at the stand-by station which is after
the Li signal has been generated but before an Lg signal
gate 185 immediately initiates a jam signal. When the
relay 182 is energized the relay contacts 249 are opened 70
has been generated, there would be a false “alarm” sig
and a sustained jam signal is supplied, as described
nal produced. The Lg signal under these circumstances
earlier.
would not be available to inhibit the L)‘ pulse and hence
The generation of this last-described jam signal is pre
the Lf pulse would cause an alarm signal. Therefore in
vented if the Tb pulse from source 53, transmitted along
the “demand" mode, since the item is stopped at the
line 253, resets ?ip-?op 239 before the delayed Ta pulse
standby station, the Lf signal is prevented from being
3,114,902
'
11
12
.
transmitted through the AND gate 283 by the application
trailing edge or the positive voltage shift 337, the circuit
of a negative “demand” signal to AND gate 283. Sec
ondly, in the “demand” mode when the item is ejected
is measured by the duration of the negative gate signal
339. If this gate signal is to be terminated early, this
from the stand-by station it’s leading edge signal Lg
would ?nd no leading edge signal Lf to be compared
against since the Li signal would have been inhibited at
gate 283 as just described. Therefore, the Lg signal is
also inhibited at gate 289 by a negative signal on line 237.
There is further included in FIG. 3 an eject pulse at
source 297, which pulse is delayed at multivibrator 299, 10
transmitted through the pulse standardizer 391, passed
through the OR gate 303, to attempt to fully condition
the AND gate 293. This attempt byrthe eject pulse to
fully condition the AND gate 293 may be prevented by
a Tg pulse from 113 resetting the flip-flop 295. The eject
pulse is somewhat analogous to the feeder clutch signal.
An eject pulse is applied when an item is to be trans
ported from the standby station. The initiation of the
eject signal is compared against the Tg pulse as just de
scribed.
There are further shown in FIG. 3 two mechanical
switches 305, 307. Actually in the system there are many
such switches conveniently located to monitor the speed
of the roller mechanisms such as the burst roller 31 shown
in FIG. 1 and rollers not shown which lie beyond the
chute blades entry. When the rollers are at rated speed,
each of the pairs of switch contacts 305, 367, etc. are
closed so that the voltage appearing at junction point
309 is relatively positive, thereby not providing a signal
to cause the ?ip-?op 311 to be set. In the copending US. 30
application entitled “Item Handling Apparatus” by F. V.
Palasciano, Serial No. 816,005, ?led May 26, 1959, now
Patent 3,022,907 and assigned to Burroughs Corporation,
such mechanical switching means are described and
claimed.
Consider now FIGS. 4a and 4b which are schematic dia
grams of di?ierent arrangements of delay multivibrators,
versions of which are used throughout the system. When
the delay multivibrator in FIG. 4a is in its quiescent state
there is current ?ow from the ground terminal 313 to the
negative voltage terminal 315. This provides a relatively
negative potential at point 317. Simultaneously the
transistor 319 is conducting and the junction point 321
is at a potential slightly less than ground. The potentials
at 317 and 321 provide an initial charge across the ca
pacitor 323 as shown by the symbols. With the transistor
319 conducting, point 335 is slightly less than ground and
therefore transistor 327 is conducting. In the quiescent
can be considered as a signal delay device whose delay
may be done by applying a positive signal to terminal
34-3.
The delay multivibrator of FIG. 4b is an arrangement
to provide a pulse output. The circuit operates as did
the circuit of 4a excepting that emitter follower transistor
327 is not present. Instead a pulse standardizer circuit
341 is connected to point 335. When transistor 319 is
cut off, during the gate time, the condenser 324 discharges.
When the transistor 319 commences conducting, the con
denser 342 commences charging and during its charging
time the transistor 34-4 is turned off (until base 354 be
comes sufficiently negative to turn on transistor 344)
thereby providing the pulse 345 at output terminal 350.
Th-roughout the system there is frequent reference made
to a pulse standardizer identi?ed in FIG. 4b as the circuit
3%. The time to charge the condenser 342 is dependent
upon the RC time constant as determined by the capacitor
342 and the resistor 352. The time necessary to charge
the condenser 3452 is relatively short and hence there is a
pulse type output 346 appearing at terminal 354}.
In FIG‘. 5 there is shown a schematic of a beam-of
lig'nt circuit. The photosensitive transistor 351 responds
to light striking its base element. Obviously the transis
tor can be replaced by some other form of photosensi
tive device. When a leading edge of a check crosses the
beam of light the photosensitive transistor 351 conducts
less and the point 353 experiences a negative voltage shift,
while when the check has travelled through the station
and the beam of light again impinges on transistor 351
causing it to conduct more, the point 353 experiences a
positive voltage shift. Waveform 355 shows the leading
and trailing edge voltage shifts as they appear on the
secondary Winding 357 of the transformer. These two
signals are ampli?ed at the ampli?er 359.
Consider the leading edge voltage shift 36]. of wave
form 355. If this signal becomes more negative than
the level 363 the transistor 365 conducts and goes to sat
uration providing an ampli?ed leading edge signal 367
which may be inverted to appear as an ampli?ed lead
ing edge signal 369 if the operation requires it. If the
trailing edge voltage shift 371 becomes more positive than
level 373 the transistor 375 becomes cut off to provide
the ampli?ed trailing edge signal 377.
With a preferred embodiment of the present invention
described above the signal delay means delayed a signal
When there is a negative voltage applied to terminal 50 for a period of time slightly longer than the time that it
329, the transistor 325 commences to conduct, causing
would take for an item travelling at a preferred speed
the potential of point 317 to become closer to ground.
to move from one station to the next. Such a delay
The positive voltage developed across the capacitor 323
time was chosen because of the particular monitoring
is now measured from a voltage level closer to ground
duties of the system related to checking that an item was
at point 317 thereby cutting off the transistor 319. When 55
travelling at the preferred speed. The present invention
the transistor 319 is out off, the transistor 327 commences
could be adapted to be used with a system where the
to conduct more heavily, providing a relatively negative
monitoring duties are to check that the items are not
output at terminal 331. The transistor 319 will remain
travelling faster than the rated speed, in which case the
cut off until the capacitor 323 discharges to a point
where the potential of the base of transistor 319 is at 60 signal delay means would delay the signals for less than
the time it would take an item to travel between two
ground or slightly below ground. The time needed for
stations at a preferred speed. The present invention
such a discharge is dependent upon the RC time con
might also be adapted to provide a tolerable period in
stant as determined by the capacitor 323 and the resistor
333. There is a feedback operation involved by virtue
which an item should arrive at a second station after
of the feedback circuit 349 which provides regenerative
having been observed at the ?rst station. In this last
action at transistor 325. When the capacitor 323 is suf
mentioned application the signal delay means would delay
?ciently discharged, the transistor 319 will commence con
the signal for a shorter period of time than the time
state transistor 325 is not conducting.
ducting, raising the potential of the point 335 substan
it would take an item to travel from one station to
tially close to ground level, thus reducing the conduction
the next at the preferred speed. The output of the
of transistor 327. When the transistor 327 is conduct 70 delay means would be connected to trigger a monostable
ing, as in its quiescent state, there is seen at the output
terminal 33-1 a positive voltage shift thereby providing
the lagging edge of the negative pulse.
The standard negative gate signal provided at the out
put terminal 331. is used in various ways. By using the
multivibrator or some equivalent device to provide a gat
ing signal. The gating signal would start before the
item should arrive and end after it should have arrived.
If in fact the item arrived before the gating signal started,
3,114,902
or after it ended, the item would be considered to be
respectively travelling too fast or too slowly.
While I have described‘ above the principles of my
invention in connection with speci?c apparatus, it is to
be clearly understood that this description is made only
by way of example and not as a limitation to the scope
of my invention as set forth in the objects thereof and
in the accompanying claims.
What is claimed is:
14
to the rated speed of said item in transport and the dis
tance between said ?rst and second station, signal detect
ing means connected to receive said delayed ?rst moni
tor signal and to receive said second monitor signal to
detect which one of said signals has been ‘received prior
in time, bistable means connected to said detecting means
to be transferred to its ?rst state if said ?rst monitor
signal has been received by said detecting means prior
in time, a signal sustaining means connected to receive
port along an item transport path comprising, ?rst moni 10 an output signal from the ?rst state of said bistable means
to‘ be responsive thereto and provide a sustained signal in
tor signal source means located at a ?rst station along
the event said bistable means should be erroneously
said item transport path to produce a ?rst monitor sig
altered.
nal when an item has been transported within said ?rst
5. A monitoring system for use along an item trans
station, second monitor signal source means located at 15
port path comprising, item transport means including an
a second station along said item transport path to produce
item transport path and means for causing items to travel
a second monitor signal when an item has been trans
1. A monitoring system for use with items‘ in trans
ported within said second station, signal delay means
the length of said item transport path, feeder monitor
connected to said ?rst monitor signal source to receive
signal source means operative in conjunction with said
nected to receive said delayed ?rst monitor signal and
said transport path at an item input station, :feeder moni
tor signal delay means connected to receive said feeder
said‘ ?rst monitor signal and delay said ?rst monitor signal 20 item transport means to provide feeder monitor signals
when said transport means operates to feed items into
for a predetermined time, signal detecting means con
to receive said second monitor signal to detect which one
of said signals has been received prior in time, said sig
nal detecting means including a bistable device and a
coincidence device, said bistable device having a ?rst
state input adapted to receive said ?rst monitor signal, a
second state input adapted to receive said second monitor
signal and a ?rst state output, said coincidence device
monitor signals and respectively delay each of said feeder
monitor signals for a predetermined time, said predeter
mined time related to the rated speed at which items are
transported along said transport path, ?rst monitor signal
source means located at a ?rst monitoring station to
produce ?rst monitor signals as each item is transported
adapted to receive said delayed ?rst monitor signal and 30 Within said ?rst monitoring station, a bistable device hav
ing a ?rst state input adapted to receive said feeder moni
said ?rst state output of said bistable device to provide
tor signal a second state input adapted to receive said
and output whenever said‘ delayed ?rst monitor signal
?rst monitor signal and having a ?rst state output, a
occurs prior‘ to said second monitor signal and utility
coincidence detecting device coupled to said ?rst state
means connected to said signal detecting means and re
output of said bistable device and adapted to receive said
sponsive to the output of said coincidence device.
delayed feeder monitor signal for providing an output
2. A monitoring system for use with items in transport
along an item transport path comprising, ?rst monitor
signal source means located at a ?rst station along said
signal whenever said delayed feeder monitor signal occurs
prior to said ?rst monitor signal, and utility means cou
pled to said coincidence device and responsive to- the
item transport path to produce a ?rst monitor signal when
an item has been transported within said ?rst station, 40 output signal of said coincidence device.
6. A monitoring system for use along an item trans
second monitor signal source means located at a second
port path according to claim 5 wherein there is further
station along said item transport path to produce a sec
included signal control means connected to said feeder
ond monitor signal when an item has been transported
monitor signal source to be responsive to a single item
within said second station, signal delay means connected
transported through said transport path to inhibit a sec~
to said ?rst monitor signal source to receive said ?rst
ond of said feeder monitor signals from being generated
monitor signal and delay said ?rst monitor signal for a
even through said item transport means is operative.
predetermined time, said predetermined time being re
lated to the rated speed of said item in transport and the
distance between said ?rst and second station, a bistable
7. A monitor system for use along an item transport
path according to claim 5 wherein there are further in
?rst monitor signal, a second state input adapted to re
ceive said second monitor signal and a ?rst state output,
a coincidence detecting device coupled to said ?rst state
output of said bistable device and adapted to receive said
in response to said transport means operating at its rated
device having a ?rst state input adapted to receive said 50 cluded electromechanical switching means which are re
sponsive to the operation of said item transport means,
said switching means completing an electrical circuit path
delayed ?rst monitor signal for providing an output sig
speed and opening said electrical circuit path in response
to said transport means operating below its rated speed,
and alarm signal means connected through said electrical
circuit path to provide an alarm signal when said path is
nal whenever said delayed ?rst monitor signal occurs
prior to said second monitor signal.
opened.
3. A monitoring system for use with items in transport
8. A monitoring system for use with items in transport
along an item transport path according to claim 2 where
in said signal delay means delays a signal for a period 60 along an item transport path comprising, ?rst monitor
signal source means located at a ?rst station along said
of time that is related to the quotient of the distance be
item transport path to produce a ?rst monitor signal when
tween said ?rst and second station divided by the speed
an item has been transported within said ?rst station, sec
of said item in transport travelling therebetween.
ond monitor signal source means located at a second sta
4. A monitoring system for use with items in transport
along an item transport path comprising, ?rst monitor 65 tion along said item transport path to produce a second
monitor signal when an item has been transported within
signal source means located at a ?rst station along said
said second station, ?rst and second signal delay means
item transport path to produce a ?rst monitor signal when
to provide a temporary signal storage means for signals
an item has been transported within said ?rst station, sec
from a subsequent item at said ?rst signal delay means
ond monitor signal source means located at a second
while
said monitoring system is operating on a signal
station along said item transport path to produce a 70
from a prior item which signal is passing along said sec
second monitor signal when an item has been transported
ond signal delay means, said ?rst signal delay means
Within said second station, signal delay means connected
connected
to receive and delay said ?rst monitor signal
to said ?rst monitor signal source to receive said ?rst
for a ?rst predetermined time, said second signal delay
monitor signal and delay said ?rst monitor signal for
means connected to receive and delay said delayed ?rst
a predetermined time, said predetermined time related
monitor signal for a second predetermined time, each
3,114,902
15
of said ?rst and second predetermined times being related
to the rated speed of said items transport, signal detecting
means connected to receive said ?rst monitor signal (1)
from said ?rst signal delay means and (2) from said sec
ond signal delay means, said signal detecting means being
further connected to receive said second monitor signal
to detect if said ?rst monitor signal from said second
signal delay means is received prior in time, and utility
means coupled to said signal detecting means to be re
sponsive if said ?rst monitor signal from said second
signal delay means has been received by said detecting
means prior in time.
9. A monitoring system for use along an item trans
port path comprising, feed mechanism signal source
means operative in conjunction with item transport means 15
to provide a feed mechanism signal when said transport
means operates to feed items into said transport path
at an item input station, pulse generating means coupled
to receive said feed mechanism signal and generate an
initial feeder monitor signal in response to starting said 20
transport means, ?rst monitor signal source means located
at a ?rst monitor station along said path to produce ?rst
monitor signals as each item is transported :within said
?rst monitoring station, signal control means connected to
receive said feed mechanism signal and be controlled
thereby, signal recirculating circuitry coupled to receive
said v?rst monitor signals and recirculate them to said
signal control means, said control means passing said
recirculated ?rst monitor signals when said feed mecha
nism signal is applied thereto to provide feeder monitor 30
signals therefrom, feeder monitor signal delay means con
nected to receive said feeder monitor signals and respec
ti-vely delay each of said feeder monitor signals for a
predetermined time, said predetermined time related to
the rated speed at which items are transported along said
16
transport path, signal detecting means connected to re
ceive said delayed feeder monitor signals and said ?rst
monitor signals, said signal detecting means to detect
with respect to an associated ?rst monitor signal and
feeder monitor signal whether said ?rst monitor signal
is received prior in time to said delayed feeder monitor
signal, and utility means coupled to said signal detecting
means to be responsive if said ?rst monitor signal has
been received by said detecting means second in time.
10. A monitoring system according to claim 9 wherein
there is further included second control means coupled
to said signal control means to temporarily terminate
the recirculation of said ?rst monitor signals.
References Cited in the ?le of this patent
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2,931,916
2,982,404
2,982,943
3,024,414
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