US2145667A

US2145667A - Watchman's service system

Info

Publication number: US2145667A
Application number: US102108A
Authority: US
Inventors: Norman H Saunders; Morris E Griffins
Original assignee: Associated Electric Laboratories Inc
Current assignee: Associated Electric Laboratories Inc
Priority date: 1936-09-23
Filing date: 1936-09-23
Publication date: 1939-01-31
Anticipated expiration: 1956-01-31

Description

Jam. 31, 1939- N. H. SAUNDERS ET AL 56 WATCHMANS SERVICE SYSTEM i Filed Sept. 23, 1936 3 Sheets-Sheet 1 'INVENTORS NORMAN H. SAUNDERS BY 5 MORRIS E. GP/FF/NS.

ATTORNEY.

Jan. 31, 11939. N. H. SAUNDERS ET AL I 2,145,6fi7

WATGHMAN S SERVICE SYSTEM Filed Sept 23, 1956 s Sheets-Sheet 2 INVENTORS NORMAN H. SAUNDERS MORRIS E. GP/FF/NS If. 31, 1939.. N. H. SAUNDERS ET AL y fi WATCHMAN'S SERVICE SYSTEM Filed Sept. 23, 1936 3 Sheets-Sheet 3 G Hl T0 CONN BANKS k .INVENTORS NORMAN H. SAUNDERS BY MORRIS GR/FF/NS.

ATTORNEY Patented Jan. 31, 1939 UNITED STATES WATCHMANS SERVICE SYSTEM Norman H. Saunders, Homewood, and Morris E.

Griffins, Western Springs, 1111., assignors to Associated Electric Laboratories, Inc, Chicago, 111., a corporation of Delaware Application September 23, 1936, Serial No. 102,108

12 Claims.

The present invention relates in general to watchmens service systems, and more in particular to a watchmans service system which is auxiliary to or forms part of an automatic private branch exchange telephone system. The object of the invention is to produce a new and improved watchmans system of this character.

The invention and the various features of improvement which it includes will be described hereinafter with reference to the accompanying drawings, which show by means of conventional circuit diagrams the equipment by which. the invention is carried out and also so much of the equipment of an automatic private branch exchange as is necessary to enable the invention to be understood.

In the drawings Fig. 1 shows an automatic telephone station which may be a station of a private branch exchange.

Fig. 2 shows control apparatus for a particular route, and

Fig. 3 shows equipment at a supervisors station.

Referring to the drawings, Fig. 1 shows at the left an automatic telephone station A, which is a station of the private branch exchange. The exchange may be of nine-hundred line capacity, that is, there may be nine-hundred stations such as station A. Each station has a line switch such as LS in which its line terminates at the automatic switchboard and which is used for outgoing calls.

Calls are completed by means of selectors and connectors. The lineswitches such as LS may be divided into groups and each group has access to a group of selectors. The selectors have access in common to nine groups of connectors. One of the selectors is shown at S, Fig. 1, but no connectors are shown as they are not involved in the invention.

The lineswitches may be of the well known rotary type in which the wipers have no home position and move in a forward direction only. The selectors and connectors may be of the well known Strowger type.

The requisite number of telephone stations located at strategic points throughout the premises served by the branch exchange are selected as watchmens stations. There may be as many as sixty of these watchmens stations according to the present disclosure, and since this is a much greater number of stations than can be taken care of by one watchman it will be assumed that they are divided into three groups or routes, each handled by a different watchman. Station A is the No. 1 station on route 1, which includes a total of ten stations, although any single route may have as many as twenty-four stations.

For each route there is provided a control apparatus. Fig. 2 shows the control apparatus for route 1, which comprises a timing switch TS, a station switch SS, and a checking switch CS, together with the relays and circuit connections shown. The three switches mentioned may be ordinary twenty-five point rotary lineswitch mechanisms.

The stations selected as watchmens stations differ from the rest of the telephone stations by having their test conductors in the exchange connected to the banks of one of the station switches such as SS, Fig. 2. Explaining this briefly, it has been mentioned that station A is the No. l watchmans station on route 1. The test conductor 9 is therefore connected, by means of a conductor lfil, to the first contact in the bank of wiper I33 of station switch SS, Fig. 2, it being recalled that the control apparatus in Fig. 2 is the control apparatus for route 1. The test conductors of watchmans stations 2, 3, etc., on route 1 are connected in regular order to the second, third, etc. contacts in. the bank of Wiper I33. Thus conductor I62 extends to the test conductor of station No. 2, while conductor I63 extends to the test conductor of station No. 3. In order to avoid complicating the drawings, the complete circuit connections of only one station have been shown, but it is thought that the arrangement will be clearly understood from the foregoing. The stations on routes 2 and 3 are of course connected up the same way, except that instead of being connected to the station switch in Fig. 2, the test conductors of the stations on routes 2 and 3 are connected to the station switches associated with the corresponding routes.

When a watchman makes a report from a station he uses the automatic telephone at such station and the exchange switchboard to establish a connection with the control apparatus for the particular route he is on and to which the reporting station belongs. In order to enable the proper route control apparatus to be selected from any station a plurality of route switches are provided. There may be two of these switches, one of which is shown complete at RS, the other being indicated at RS. These route switches are of the single motion rotary type, lineswitch mechanisms may be used; but are directively controlled and have access to the three control apparatuses for the three routes. The first level of the banks of the selectors such as S may be used to give access to the route switches.

Common to all the routes is a recording device R indicated by the dotted rectangle in Fig. 2. This recording device may be of the type shown in Sengebusch Patent No. 1,862,200, but other electrically operated recording devices could be used. The Sengebusch recording device comprises a row of sixty individual station magnets to the first ten recording positions. 20

and a parallel row of sixty type wheels, each of which bears the minutes designations from 1 to 60. There is also a common type wheel bearing the hours designations. Time controlled mechanism periodically advances the minutes wheels and the hours wheel to keep them set in accordance with the time of day. When any magnet is operated from the corresponding station, apparatus is set in motion which presses a chart against the minutes wheel corresponding to the operated magnet, thereby printing the time in the correct station column on the chart. After each printing operation the chart is advanced, and once every hour the hours wheel is caused to print. The complete recorder, therefore, affords means for making a time record on a single chart of reports from sixty stations.

The ten stations on route 1 may be assigned To accomplish this the first ten contacts in the bank oi. wiper I34 of station switch SS, Fig. 2, are connected to the first ten magnets of the recorder. Fig. 2 shows four of these magnets and the circuit connections. If there are fifteen stations on route 2, these stations may be assigned to fifteen positions in the recorder beginning with position sixteen, leaving five vacant positions for growth in route 1; and the assignment is effected by conmeeting the first fifteen bank contacts in the bank of the wiper similar to I34 of the station switch of the route 2 control apparatus to fifteen consecutive magnets of the recorder, beginning with the sixteenth magnet. Assignment of the stations on route 3 is made in a similar manner.

The system contemplates that a head watchman or supervisor will be on duty during the hours when the watchmen are on their rounds, and the equipment shown in Fig. 3 is provided for the use of this supervisor. The supervisors telephone is shown at B, and is provided with a lineswitch LS for making outgoing calls. OGK is a key for connecting up the lineswitch LS and MK is a. monitor key for communicating with a watchman when the watchman is reporting. There are as many keys MK as there are route switches such as RS. TL is a trunk lamp associated with monitor key MK and individual to route switch RS. TL is a second trunk lamp for the key MK and the route switch RS. GK is a guard key for notifying reporting watchmen that the supervisor wants to communicate with them, and G is a guard lamp. The key GK and lamp G are common to the route switches. RL are route lamps, one for each route, and RA are route alarm lamps. SL are station lamps, one for each station. These station lamps are preferably arranged in three rows, opposite the three route lamps and three route alarm lamps. LRK is a combined listening and ringing key. Associated with this key is a trunk circuit and trunk line leading to a telephone C, which may be located at the nearest police station.

The operation of the system will now be described, considering for this purpose the round of the watchman on route 1. It will be understood that the watchman visits the stations on his route in regular order, beginning with station #1, and reports in from each station. As each report is made the time is recorded on the recording device in the column corresponding to the reporting station and thus a complete record is made which can be checked at any time in order to determine if the watchman has performed his duties properly.

apparatus shown in Fig. 2. This is all that the watchman has to do in order to report from the station. The digits which the watchman has to dial in this instance are the digits 1 and 1, that is, the watchman dials the number 11. He dials this same number from each station on his route. It may be stated here that the watchman on route 2 always dials the number 12, while the watchman on route 3 always dials the number 13.

Responsive tothe removal of the receiver at station A, a bridge is closed across the line conductors 2 and 3, which energizes the line relay 3 of the lineswitch LS. On energizing, relay 3 closes a circuit for the switching relay 4 in series with the stepping magnet 8, and at the same time connects the test wiper I to the junction of the switching relay and stepping magnet. If at this time the wipers of the lineswitch are standing on a busy trunk line, the contact engaged by the test wiper I will have a ground potential on it and the switching relay 4 will be short circuited. This ground potential is also efiective to energize the stepping magnet 8, advancing the switch wipers in search of an idle trunk line. In the present case it will be assumed that the selector S with which the wipers of the lineswitch LS are associated is idle, and consequently when the line relay 3 energizes the switching relay 4 energizes immediately thereafter, and extends the line conductors 2 and 3 through to the wipers 5 and 6 and thence to the line relay I5 of the selector S. The energization of the switching relay disconnects the line relay 3 but this relay is slow to fall back and holds up the switching relay 4 until ground is received back over the release trunk conductor II. The switching relay 4 also establishes a connection between the test wiper 'I and the test conductor 9.

When the connection is extended to the selector S by the lineswitch LS, as above described, the line relay I5 is energized over the calling line and closes a circuit for the slow-acting release relay I6 at 30. On energizing, the latter relay grounds the release trunk conductor at 33 to establish a. holding circuit for the switching relay 4 of lineswitch LS. Relay It also connects the test wiper 24 to the upper winding of the test relay I8 at 32 and prepares a circuit for the vertical magnet 20 at 3 I. Relay IT is also energized at this time, by ground on the release trunk conductor I I, the circuit extending through the upper pair of off-normal springs ON. Ground on conductor II also energizes the lower or polarizing winding of the electropolarized test relay I8.

The watchman may now dial the first digit of the number 11, thereby interrupting the circuit of the line relay I5 a single time, and causing this relay to fall back once and transmit an impulse to the vertical magnet 20. Responding to this impulse, the vertical magnet raises the shaft carrying wipers 22-24 one step, so that the wipers stand opposite the first level of contacts in their banks. When the shaft is raised, the three sets of off-normal springs are shifted and at the upper set the circuit for the upper winding of relay I1 is broken. This relay does not fall back immediately, however, because it receives an impulse from the line relay I5 in parallel with the vertical magnet 20. A short interval after the switch has been stepped up by this impulse, relay II falls back, and the line relay. I5 now being in energized position, a circuit is closed for the rotary magnet 2i. This circuit includes the lower pair of offnormal springs ON, which are now closed. Upon the closure of this circuit the rotary magnet begins to operate in the manner of a buzzer, as it interrupts its own circuit, and rotates the switch shaft carrying wipers 22-25 in search of an idle route switch, such as RS.

The idle condition of a route switch is indicated by the presence of a battery potential on the associated test conductor such as 4|, and assiuhing that the route switch RS is idle, test conductor II will have a battery potential on it, the potential being derived by the normal connection of this conductor to the upper winding of relay 52. When the hunting selector S arrives at contacts 25--21, therefore, which are associated with the switch RS, the test wiper 2-1 will find a battery potential and the test relay I8 will be energized over its upper winding to ground on the release trunk conductor I I. On energizing, relay Ill connects the release trunk conductor II with the test wiper 24 at 28, opens the release magnet circuit at 29, and switches the incoming line conductors from the line relay I5 to the wipers 22 and 23. The line relay I5 accordingly falls back and breaks the circuit of the release relay I5, but this latter relay is slow acting and maintains ground on the release conductor II until a holding ground is fed back from the selected route switch RS. Relay I8 holds up by its lower winding alone.

When the route switch RS is selected as described in the foregoing, relay 52 is energized in series with relay II and after I8 has operated, relay 52 holds up by ground fed forward over 1!. Also the line relay 55 is energized over the calling line and at 6E! closes a circuit for the slow-acting relay 5i. On energizing, relay 5| grounds the release trunk conductor 41 at 64, thereby completing a holding circuit for the selector S and lineswitch LS. In addition to the foregoing, relay 5I prepares locking circuits for relays 54 and 55 at B2, prepares an energizing circuit for relay 56 at 63, and prepares a stepping circuit for stepping magnet 51 at 65. It may be mentioned at this time that the line relay 5|], on energizing, closes a circuit for the trunk lamp TL, Fig. 3, at 5!. The lighting of this lamp indicates to the supervisor that a watchman is calling in on the first route switch RS.

The watchman may now dial the second digit in the number 11, with the result that the line relay 55 deenergizes once and transmits one impulse to the stepping magnet 51, the circuit extending from ground at Gil by way of 55, 61, and winding of 51 to battery. The stepping magnet 51 responds to this impulse by advancing wipers 88 one step, so that the wipers 85-81 establish connection over conductors 89-9I with the control apparatus in Fig. 2. When the wiper 88 leaves its normal position it breaks the circuit for the upper winding of relay 52, but this relay holds on momentarily due to receiving the stepping impulse in parallel with the magnet 51. When relay 52 falls back it breaks the stepping circuit at 61, and at 66 completes a circuit for the switching relay 55. The energizing circuit for the switching relay 55 extends from ground at 18 by way of contacts of switching relay 56' of route switch RS, contacts controlled by armature 19 of relay 55, lower winding of relay 55, 55, 53, I5, 13, and upper winding of relay 56 to battery. Relay 55 energizes over the above circuit and establishes a locking circuit for itself at 19. At 18 relay 55 breaks the chain circuit over which it was initially energized, and this prevents the energization of switching relay 55 in the other route switch, if another watchman should report in at this time. In addition to the above, relay 55 grounds wiper 85 at 15, prepares a circuit for relay 55 at 11, establishes a holding circuit for relay 5I at 80, and at 8! substitutes the booster battery 82 for the previously established ground connection to the release trunk conductor 4|. The purpose of this latter operation will be explained presently. The object in closing the holding circuit for relay 5I is to hold up the connection and insure its being recorded in the event that the watchman should hang up his receiver prematurely.

The operation of the control apparatus in Fig. 2 may now be considered. When relay 55, Fig. 1, grounds wiper 85 at 15, a circuit is completed over conductor 89 for relay Illll. A branch of this circuit extends to the route lamp RL for route 1 and lights the lamp to notify the supervisor that a report is being made from a station on route 1. On energizing, relay IIII] closes a circuit for relay II]! at H2, and a circuit for test relay I52 at III. Relay I52 is a quick acting relay, while relay I5! has a slug at its upper end and is slow to energize. Relay I02 is also a marginal relay and cannot operate from a grounded test conductor. That is, it is unable to energize when supplied with current from the exchange battery alone. At the present time, however, since the booster battery 82 has been connected up by relay 55, Fig. 1, and since the station switch SS is standing in first position, corresponding to the first watchmans station, the test relay I52 has a circuit which includes the exchange battery and the booster battery 82 in series, and it immediately energizes, opening the circuit for relay 161 at II1 before this relay can operate, and closing a locking circuit for itself at H6. The initial energizing circuit of relay I62 may be traced from ground by way of booster battery 82, the protective resistance associated with this battery, 8|, 54, II, 21, 24, 28, II, I, III,

5, ISI, I33 in first position, upper winding of relay I52, I15, III, the exchange battery, and thence to ground.

The energization of relay I52 closes the recording circuit at II8. This circuit extends from ground by way of H8, I29, wiper I35 in first position, and thence through the first individual station recording magnet of the recorder R to battery. Responsive to the operation of this magnet the recorder prints the time in the column allocated to station #1 of the first route. The circuit of the recording magnet is only momentarily closed, as relay I I15 is energized over a portion of the same circuit and opens the portion extending to the recorder at I29. Relay I55 also takes ground of? the conductor I10 at I32, but this conductor remains grounded at I20 as long as relay I52 remains energized. Relay I05 also closes the circuit of relay I04 at IBI.

Upon energizing, relay III I prepares a circuit for the stepping magnet I31 at I28, opens the automatic homing circuit including the said magnet at I25, closes a circuit for relay I63 at I21, and grounds conductor 90 at I25. The circuit of relay I53 may be traced from ground by way of wiper I55 in first position, I21, and winding of relay I53 to battery. On energizing, relay I53 places ground on wiper I35 at I24, thereby lighting up the #1 station lamp SL in the row assigned to route 1. In addition to the foregoing,

relay I03 prepares a locking circuit for itself at I23 and completes a circuit for connecting stepping magnet I38 of the timer switch TS to the timer T, represented herein by a cam which is assumed to be continuously rotating at the rate of one rotation per minute. The timer may be common to all the control apparatus of the several routes. The circuit for the stepping magnet I38 extends from ground by way of the contacts of the timer, I2I, I I9, I30, and winding of magnet I 38 to battery. This circuit is closed momentarily once every minute.

The efiect of grounding conductor 90 at I25 of relay I04 will now be considered. A circuit is completed for relay 55 which extends from ground by way of 525, 90, 80, TI, and winding of relay 55 to battery. On energizing, relay 55 looks itself at II, closes a circuit for buzzer relay 53 at I2, and opens the circuit of relay 55 at 13. Relay 55 accordingly falls back and opens the holding circuit for the release relay 5I at 80. The circuit for the buzzer relay 53 extends from ground in Fig. 3 by way of normally closed contacts of key GK, conductor 93, I2, 68, and winding of buzzer relay 53 to battery. Relay 53 interrupts its own circuit at 60 and produces a tone current which is transmitted through the small condenser to the lower side of the line incoming to the route switch RS. This gives the watchman, who is waiting on the line with the receiver to his ear, a signal indicating that the recording apparatus has been operated, and the watchman accordingly hangs up the receiver at station 1 and proceeds on his way to station #2.

When the receiver is replaced at station A the line relay 50 falls back and opens the circuit of release relay 5|. Relay 55 having deenergized as already explained, release relay 5| is able to deenergize and unlock relay 55, which falls back and opens the buzzer circuit at I2. Relay 5I also closes a homing circuit which may be traced from ground at the lower make-before-break contacts of relay 55 by way of the strapped contacts in the bank of wiper 88, wiper 38, 55, oifnormal contacts ON, interrupter contacts of stepping magnet 5'5, and winding of the said stepping magnet to battery. Magnet 57 is intermittently operated over the above self interrupted circuit and advances the wipers -88 step by step to home position, where the circuit is broken at wiper 83 and at the oiT-normal contacts.

While the route switch RS is being restored to normal position, the release trunk conductor 4| remains grounded over wiper 88, but when the switch reaches home position this ground is removed and since relay 5! has deenergized the release trunk conductor 4! will become ungrounded, which breaks the holding circuits for the selector S and the lineswitch LS. At the selector S the switching relay I8 falls back and closes a circuit for the release magnet I9 over 29, 30, SI, and the second pair of off-normal springs ON. The release magnet restores the switch in the well known manner and its circuit is broken at the ofi-normal contacts when the switch reaches normal position. At the lineswitch LS relay 4 falls back, but the wipers remain standing on the selector S. The falling back of relay 4 connects up the line relay 3, so that another call can be made from station A.

Returning now to the control apparatus in Fig. 2, when relay 50, Fig. 1, falls back as previously explained, it takes ground off wiper 85 at I6, and thereby breaks the circuit of relay I00, also extinguishing the route lamp RL. Relay I00 accordingly falls back, breaks the circuit for the upper winding of relay I02 at III, and opens the locking circuit including the lower winding of relay I02 at IIZ. Relay I02 accordingly deenergizes and breaks the original energizing circuit of relay I05 at H8. Whether relay I05 falls back or not at this time depends on whether or not the timing switch TS has taken a step from normal position. Only a very short time, perhaps two seconds, has elapsed since the timing circuit was closed at I2I by the energization of relay I03 and the chances are that the timing switch has not been advanced. Under these circumstances, relay I05 immediately falls back when its circuit is broken at I I8, with results which will be presently explained.

However, it may happen once in a while that the timer T will send an impulse to the stepping magnet I38 between the pulling up of relay I03 and the falling back of relay I02, and under these circumstances the timing switch TS will have taken one step at the time relay I02 falls back and breaks the circuit of relay I05 at IIB. Explaining the operation under this condition of affairs, relay I05 does not deenergize, but remains locked up over a circuit which extends from ground by way of wiper I39 of TS, contact I29, and winding of relay I05 to battery. Relay I02 being deenergized and relay I05 being energized,

a homing circuit is established for the timing switch TS which extends from ground by way of wiper I39, interrupter contacts of stepping magnet I38, IIQ, I30, and winding of the stepping magnet I30 to battery. Magnet I38 operates over the above circuit to automatically advance the wipers of the timing switch to normal position, where the circuit is broken at wiper E39 and the switch stops.

When wiper I39 arrives at home position, the

locking circuit of relay I05 is broken and the relay deenergizes, breaking the circuit of relay I04 at I3I and closing at the same point a circuit for the stepping magnet I31 of the station switch SS. Relay I04 is slow to release and the stepping circuit for magnet I3? is maintained until relay I04 J has had time to fall back. The impulse thus delivered to magnet I3! operates the magnet and upon its deenergization the wipers I33I30 are moved from first to second position. When relay I04 de-energizes it opens the initial energizing circuit of relay I 03 at I2'I, but relay I03 is slow acting and holds on until the advance of the switch SS from first to second position establishes a locking circuit which may be traced from ground by way of wiper I35 in second position, bank strapping, I23, and winding of relay I03 to battery. Relay I03 holds up over this circuit until the watchman has called in from the last station on route 1.

The falling back of relay I05 and the continued energization of relay I03 serve to connect the timer T with the stepping magnet I38 of the timer switch over an obvious circuit which includes contact I2I of relay I03 and the back contact I30 of relay I05. The advance of wiper I30 from first to second position extinguishes the #1 station lamp SL for route 1, and lights up the #2 station lamp. This indicates to the supervisor that the watchman on route 1 has left the #1 station and is on his way to the #2 station.

Reviewing briefly the condition of the apparatus at this juncture, the station switch has been advanced from position 1 to position 2, so that the test relay I02 has been connected through wiper I33 with conductor I02, which extends to and connects with the test conductor of station #2. Thus a circuit has been prepared so that the test relay I02 can respond when the report is made by the watchman from the #2 station. The #2 lamp SL for route 1 has been lighted over wiper I 36 so that the supervisor knows that the watchman is on his Way to the #2 station on his route. Also the timing switch TS is advancing at the rate of one step per minute. The primary purpose of this timing switch is to light the route alarm lamp RA for route 1 in case the watchman fails to report at any station on time. The time allowed for the watchman to go from one station to the next is variable within certain limits, but as disclosed herein the time is about ten minutes, as the conductor I'II over which the alarm is brought in is connected to the tenth contact of the bank of wiper I40. Obviously the time could be changed by shifting this conductor to a different contact.

In order to explain the function of the timing switch more fully, it will be assumed now that the watchman fails to report from the #2 station within the time allowed. After ten steps have been taken by the timing switch TS, a circuit is completed for relay I Ill, the circuit extending from ground at I32 by way of wiper I40, conductor Il' i and winding of relay I Hi to battery. On energizing, relay I It looks itself at I51, prepares a circuit for the ringing relay 203 at I58, and closes a circuit for the route alarm lamp RA of route 1 at Hill. The lighting of the route alarm lamp notifies the supervisor of the fact that the watchman on route 1 has failed to report at some station within the proper time, and glancing at the station lamps SL the supervisor sees at once that the station at which the watchman is overdue is station #2.

The supervisor may now follow any one of several courses. As the watchmans rounds are preferably staggered as to time, the watchmen for routes 2 and 3, or one of them, may be at the supervisors ofiice where the watchmen spend their time when they are not actually travelling on their rounds. If another watchman is present, therefore, the supervisor will generally send him out to investigate.

In the event that none of the other watchmen are around, the supervisor may call one of them by operating the guard key GK, Fig. 3. The guard key GK is common to both of the route switches RS and RS and when it is operated ground is removed from conductor 93 and the corresponding conductor extending to the other route switch. It follows from this that the next watchman to report fails to obtain a signal by the operation of the buzzer such as 53 and he will wait until the supervisor can talk to him.

Assume for instance, that the watchman on route #2 calls in from some station on his route and seizes the route switch RS. Having dialled the number by which the report is effected, the watchman will listen in the receiver for the signal which notifies him that recording has taken place and that he is free to proceed to the next station. As explained hereinbefore this signal is produced by the energization of relay 55, which closes a circuit for the buzzer relay 5-3 at i2. Under the present conditions, however, the circuit of the buzzer relay 53 cannot be closed because it has been opened at the key GK. The supervisor knows that the watchman has completed dialling because of the lightkey MK in order to establish a connection between his telephone line 20620'I and the line incoming to the route switch RS. After removing the receiver at telephone B the supervisor is now able to talk to the waiting watchman and give him instructions with regard to investigating the reason for the failure of the watchman on route 1 to report at station #2.

It will be assumed now that either with or without the assistance of the second watchman, the Watchman on route 1 arrives at station #2 and reports in.

The number 11 is dialled as previously explained, and the switches are operated in the same manner, connection being established from the #2 station over its associated lineswitch such as LS, the selector S or a similar selector, and one of the route switches, the route switch RS, for instance. The control apparatus in Fig. 2 operates in the same manner as previously described. Relay IIlfi energizes, followed by the energization of relay I02. The energization of relay I02 is followed by the operation of the recorder R and an instant later relay I05 operates. Relay Iil5 operates relay Iii l, which grounds conductor 90 and energizes relay 55 to close the buzzer circuit and break the circuit of relay 56. If the supervisor has restored key GK the watchman will receive a signal in the usual manner and will hang up the receiver and proceed to the next station. In this case, however, the supervisor will probably have left the key GK in operated position so that the watchman will be sure not to leave the #2 station before the supervisor can talk to him. The automatic switches in use by the watchmen for reporting, of course, do not release until the watchman hangs up the receiver. After receiving the Watchmans explanation, the supervisor may restore the key GK and also the key such as MK which was used for establishing the talking connection. The watchman hangs up and proceeds to the next station.

When the relay 5G in Fig. l deenergizes, it allows relays I and I02, Fig. 3, to be deenergized, and the falling back of the latter relay breaks the locking circuit of relay Mb, relay being still in operated position. Relay IIii accordingly falls back and extinguishes the route alarm lamp RA of route 1. Relay Hi2 also breaks the initial energzing circuit of relay Hi5, but this relay remains locked up over wiper E39 of the timing switch until the timing switch. has been restored to normal. The restoration of the timing switch to normal takes place immediately following the deenergization of relay M2, as previously explained. When the timing switch reaches normal position relay IE5 is unlocked and deenergizes, breaking the circuit of relay iild. Relays I05 and I04 now transmit an impulse to stepping magnet I3! of the station switch SS, which responds to the impulse by advancing the wipers I33l36 to third position. The move-- ment of the wiper I33 from second to third position prepares the circuit of the test relay E02 by way of conductor I63, which is connected to the test conductor of the #3 station. The movement of wiper I35 from second to third position extinguishes the #2 station lamp SL on route 1 and lights the #3 station lamp.

Reverting now to the point where the watchman on the #1 route failed to report in at the #2 station within the allotted time, it will be assumed that no Watchman is available to send out to investigate, and it will be assumed further that the routes are so far apart that it is not practicable to call a watchman from one of the other routes to investigate the trouble on route #1. In these circumstances the supervisor will usually deem it necessary to go himself to investigate the trouble. Before leaving, however, he may call the police station at which telephone C is located, which is done by removing the re ceiver from the telephone B and operating the key LRK first to ringing position and then to listening position. When the key LRK is moved to ringing position, or to the right as it is shown in the drawings, ground is placed on conductor 205 of the trunk extending to the police station and at the same time the generator GEN is connected to the other conductor 204. This rings the bell at telephone C. When the key LRK is thrown to the left, the

line conductors

206 and 201 are extended through to the impedance coil 200, and at the same time a circuit is closed for relay 202. This relay, on energizing, connects the

trunk conductors

204 and 205 with the impedance coil 20I. The telephones B and C are then supplied with talking battery through

impedance coils

200 and 20!, respectively, and since the coils are connected by means of condensers, a talking circuit will be established, over which the supervisor can talk to the officer in charge at the police station. The supervisor may inform the oflicer of the possibility of trouble so that preparations can be made to send assistance if it should be required. After the conversation is finished the supervisor hangs up the receiver at telephone B, restores key LRK, and proceeds with his investigation, leaving the office temporarily unattended.

It will be assumed now that the watchman has merely been delayed for some reason or other, perhaps he has stopped to investigate some noise that turns out to be a false alarm. Accordingly the supervisor will send him on to report from station #2 and will return to his office. On reaching the office the supervisor may call up the police station in the manner previously described and notify them that no assistance is required.

It may happen, however, that the supervisor will run into some real trouble, making it impossible for him to return to his oifice. After about ten minutes has elapsed, as determined by the timing switch TS, a circuit is completed for the ringing relay 203. This circuit may be traced from ground at I 32 by way of wiper I40, conductor I12, I58. 2I2, and winding of relay 203 to battery. Relay 293 looks itself over conductor 2| I toground at I32 and closes a ringing circuit over the trunk line 204205 at 2I5 and 2 IS. The completion of this ringing circuit rings the bell at telephone C continuously. Knowing from this that the supervisor is in trouble, the police station will send assistance immediately. The: bell continues to ring until order is restored and the proper report is made from the #2 station, whereupon relay I I0 is unlocked as previously described to extinguish the route alarm lamp, and at the same time relay 203 is unlocked to break the ringing circuit over the line of telephone C.

The operation of the checking switch CS, Fig. 2,

will now be explained. For this purpose it may be assumed that the station switch SS is in the third position, the #3 station lamp SL for route 1 is lighted, and the watchman on route 1 is presumably on his way from station #2 to station #3. It will be assumed now that instead of reporting from station #3 the Watchman skips this station and reports in from station #4. Under these circumstances the checking switch CS is operated With results which will be pointed out.

It will be assumed that the watchman reports in by means of a lineswitch similar to lineswitch LS, the selector S, and the route switch RS. When relay 56 in the route switch RS operates and grounds wiper 85, a circuit is completed for relay I00 in the manner already described. Relay I00 connects the exchange battery to the upper winding of relay I02 at III, and at II 2 closes a circuit for the slow-to-energize relay IOI. Relay I02 fails to operate now because the station switch SS is standing in third position, whereas the watchman is reporting from the #4 station, and the booster battery 82 will be connected by way of the test conductor of the fourth station to conductor I64, connected to the fourth contact in the bank of Wiper I33. Consequently the test circuit will be open at the bank of wiper I33 and test relay I 02 will fail to operate, as stated. After an instant relay IOI operates, since its circuit is not opened at I I1, and transfers the exchange battery testing connection to the relay I09 at H5. In addition, relay IOI closes an operating circuit for the stepping magnet I60 of the checking switch CS, said circuit extending from ground at I32 by way of I i3, conductor I13, interrupter contacts of the stepping magnet I60, and the winding of the stepping magnet to battery. The above circuit is interrupted by the stepping magnet I60 each time it energizes and accordingly the checking switch CS is advanced step by step in search of the reporting station.

When wiper I4! reaches the fourth contact in its bank it will pick up the booster battery potential on conductor I64, thereby energizing test relay I09. Relay I09 locks itself to grounded conductor I13 at I50, and at I5I closes a shunt around the interrupter contacts of the stepping magnet I 60, which holds the magnet energized and prevents further stepping of the switch. In addition to the foregoing, relay I09 grounds wiper I44 at I54, thereby lighting the #4 station lamp SL on route 1, and also closes a circuit for the route alarm lamp RA for route 1 at I56. Finally, relay I09 closes the recording circuit at I52 and I53. This circuit extends from ground by way of I53, I41, I52, wiper I42, and the fourth individual station magnet of the recorder to battery. The recorder is operated to record the time in the usual way. Relay I08 is operated over a portion of the recording circuit after an instant and opens the circuit at I41. Relay I03 also closes a circuit for relay I01, but this relay is slow to energize and a momentary ground is therefore applied to conductor 9 I.

Responsive to the grounding of conductor 9|, relay 54, Fig. 1, energizes over a circuit which extends from ground by way of I48, I49, 9|, 81, and winding of relay 54 to battery. On energizing, relay 54 locks itself at 60 and opens the circuit of relay 55 at 10. It will be noted that relay 54 does not close a circuit for the buzzer relay 53 and consequently no signal will be heard by the watchman.

At the ofiice the supervisor sees the lighted route alarm lamp RA associated with route #1, and since the #3 station lamp and also the #4 station lamp are lighted, the supervisor will know why the route alarm lamp has been brought in. That is, he will know that this is not due to a delayed report but is due to reporting in from the #4 station instead of from the #3 station. The supervisor also knows by the lighted trunk lamp TL that the watchman is using the route switch RS and accordingly he will throw the monitoring key MK to talk to him. Preferably the watchman will be advised that he has reported in from the wrong station and will be instructed to go back and report from station #3.

The release of relay 5E responsive to the energizing of relay 55 of course unlocks the release relay 5i so that the switching equipment will be released when the watchman hangs up. Relay 56 falling back also ungrounds wiper 85 and breaks the circuit of relay IBIJ. Relay It?! accordingly falls back and breaks the circuit of relay IEBI, which deenergizes and opens contacts H3. Conductor I'IS remains grounded, however, over contacts I55 of relay IGQ and relay I09 remains locked up. This keeps the #4 station lamp and the route alarm lamp lighted while the watchman is on the way back to the #3 station.

When the watchman eventually reports in from the #3 station, relay I69 is energized and its energization will now be followed by the energization of relay m2 in the normal manner. The various results that ensue from the opera tion of relay I02 have been fully explained and consequently need not be gone over again. It may be stated, however, that When relay I02 falls back, ground is removed from conductor I ill at I2Il and is not replaced until relay Hi5 falls back. As a result of the ungrounding of conductor I'Ifl relay I89 becomes unlocked and the stepping magnet I60 is deenergized. The switch CS is not of the homing type and the wipers remain standing where they were. The falling back of relay I09, of course, puts out the route alarm lamp and ungrounds the wiper I M; over which the #4 station lamp has been lighted. Iowever, this #4 lamp is maintained in lighted condition due to the advance of the station switch SS from third position to fourth position. It will be apparent that if the watchman had called from the #6 station, for example, instead of from the #4 station, then the corresponding lamp, brought in through the medium of the checking switch CS, would now be extinguished.

Continuing with the regular operation of the system, it will be assumed that the watchman reports from the remaining stations in regular order. The station switch SS is stepped ahead each time that a report is made, and following the report from station #10 will be stepped to the eleventh position. The advance of wiper I35 from position 10 toposition 11 breaks the locking circuit of relay I03 and this relay accordingly falls back. On deenergizing, relay I63 closes a circuit for the stepping magnet I3! which extends from ground by way of wiper I35 in eleventh position, I22, I25, interrupter contacts of the stepping magnet I31, and winding of said magnet to battery. The magnet I3? energizes over this circuit, breaks the circuit, and on falling back advances the station switch SS from eleventh to twelfth position. In the twelfth position of wiper I35 a circuit is completed for magnet I3! which extends from ground by way of wiper I35 in twelfth position, I23, I26, interrupter contacts of stepping magnet I31, and winding of said magnet to battery. The stepping magnet I371 operates automatically over the last mentioned circuit until switch SS is advanced to position 1, where the circuit is broken at wiper I35. This restores the equipment to its normal position, where it stays until the watchman goes over his route again and reports in from station #1.

An. explanation will now be made of the operation and function of relay I06, Fig. 2, which is associated with the checking switch CS. The purpose of this relay is to prevent the tieing up of a route switch such as RS if the test relays I02 and IE9 fail to operate for some reason. A possible cause for the failure of these test relays to ing paragraph, relay IIlZ fails to operate following the operation of relay I95], and relay IdI operates to transfer the test circuit to test relay I5 9 and to start the operation of the checking switch CS. Under the assumed condition the test relay I69 will not be able to operate, and consequently the checking switch CS will continue to run and on passing through its twenty-fifth position will complete a circuit for relay I66. This circuit extends from ground by way of i I I, wiper Hit in twenty-fifth position, and winding of relay IIIS to battery. On energizing, relay IIlIi locks itself at M5, so that it remains energized after the wiper I43 has passed along, and at M6 prepares a circuit for grounding conductor SI.

ill!

Since the checking switch CS is started from some random position, it may not have tested all of the stations on passing its twenty-fifth position, but it completes the test on the second rotation, and since the test relay I09 is still unable to pull up, the switch eventually passes through its twenty-fourth position again, whereupon a circuit is completed for relay 54. This circuit extends from ground by way'of II i', wiper I43 in twenty-fourth position, I46, M9, til, 8?, and winding of relay i l to battery. On energizing, relay 5t breaks the circuit of relay 55, which falls back and breaks the circuit of relay Hit. The deenergization of this relay brings about the deenergization of relay IIII, which is followed by the stopping of the checking switch CS and the deenergization of relay I06, as will be readily understood.

The deenergization of relay 56 opens the holding circuit of relay 5I and leaves the route switch under the control of the watchman. The watchman has heard no signal and consequently he will think at first that the supervisor wants to talk to him and will wait on the line. Not hearing the supervisor come in the watchman will soon realize that something is wrong and will call the supervisor in the usual way through the automatic switching equipment of the branch exchange. When such a call comes in to the supervisor, the ringer 229 is operated and the supervisor answers the call by throwing the key OGK and removing the receiver at telephone B. The watchman is thus able to notify the supervisor that he is unable to obtain a signal responsive to reporting in from a station and the supervisor will investigate and see what the trouble is.

The invention having been described, that which is believed to be new and for which the protection of Letters Patent is desired will be pointed out in the appended claims.

What is claimed is:

1. In a watchmans system, a plurality of telephones used as reporting stations, common control apparatus including a station switch, means for maintaining said switch connected only to the station from which the next report is to be made, a recorder, means including said switch and an individual station circuit connection for controlling said recorder to record the next report when received, and means for automatically ill advancing said station switch to prepare for the next report.

2. In a watchmans system, a plurality of telephones of an exchange serving as watchmens reporting stations, test conductors for each of said stations, control apparatus including a station switch, a test circuit including said-switch and successive ones of said test conductors, means including the exchange equipment for enabling the watchman at any reporting station to gain access to said control apparatus and close said test circuit, means controlled over the test circuit for recording the report, and means for automatically advancing said station switch to include a different test conductor in the test circuit after each report is made.

3. In a watchmans system, a plurality of automatic telephones serving as watchmens reporting stations, said reporting stations being located on a plurality of different routes, a plurality of route switches, automatic switching equipment through which any reporting station may gain access to an idle route switch, an individual control apparatus for each route, means whereby the watchman at any reporting station, having gained access to a route switch, may directively control the same to establish connection with the particular control apparatus which is individual to the route on which the reporting station is located, and means for recording the time the connection is established.

4. In a watchmans system, a plurality of watchmens reporting stations, control apparatus common to said stations and adapted to receive and record reports from such stations only in a particular order, other common control apparatus adapted to receive and record reports in random order, and means whereby said second mentioned apparatus is enabled to respond to a report only if such report cannot be received by said first mentioned control apparatus.

5. In a watchmans system, a plurality of watchmens reporting stations, control apparatus common to a plurality of reporting stations and adapted to receive and record reports from such stations only in a particular order, other common control apparatus adapted to receive and record reports that cannot be received by said first mentioned apparatus, and means for actuating an alarm each time the second mentioned control apparatus is brought into use to receive and record a report.

6. In a watchmans system, a plurality of telephones of an exchange serving as reporting stations, common control apparatus for receiving and recording reports from said stations, means whereby said apparatus is enabled to receive a report at any given time from only a particular station, means including the exchange equipment whereby a connection can be extended by the watchman from any reporting station to said control apparatus, and means for transmitting a signal to the watchman only if the connection has been extended from the particular station from which the control apparatus is adapted to receive a report at that time.

'7. A system according to claim 6, characterized by the provision of means under control of a supervisor for preventing a signal being transmitted to a reporting watchman for the purpose of inducing the watchman to wait at the reporting station, and means whereby the supervisor can complete a talking connection with the reporting station.

8. In a watchmans system which comprises a plurality of routes, with a plurality of reporting stations on each route, supervisors equipment including an individual station lamp for each station on each route, said station lamps being grouped in accordance with the routes to which the associated stations belong, means for maintaining a station lamp in each group lighted to indicate the station from which the next report is to be received, and means responsive when any report is received for lighting the route lamp of the route to which the reporting station belongs.

9. In a watchmans system, a plurality of telephones of an automatic exchange used as reporting stations, common control and recording apparatus, means including equipment of the automatic exchange whereby the watchman may gain access to said common apparatus to record a report from any station, means for preventing the release of said exchange equipment while the report is being recorded, and means effective after an interval in case the control apparatus fails to function for rendering said release preventing means inoperative, whereby the watchman is enabled to restore said equipment.

10. In a watchmans system, a plurality of telephones of an automatic exchange used as reporting stations, common control and recording apparatus including a test relay for controlling the recorder and means for preselecting the test conductor of the next station due to report, means including part of the automatic exchange equipment for extending a connection from such station to said common apparatus, a holding cir cuit for the operated exchange equipment, a booster battery, and means responsive to the establishment of the said connection for closing a circuit for said relay which includes said booster battery, said holding circuit, a part of the preselected test conductor, the said relay, and the exchange battery in series with said booster battery.

11. In a watchmans system, a plurality of telephones used as reporting stations, common control apparatus including a switch, a conductor for each of said stations terminating in said switch in a predetermined order, a test circuit including said switch, means controlled over said test circuit and one of said conductors responsive to a call from one of said stations for recording that call and for operating said switch to connect with the conductor of the next station, and means responsive to calls from successive stations for controlling said switch to successively connect the conductors of reporting stations to said test circuit in the predetermined order.

12. In a combined telephone and watchmans service system, a plurality of telephones of a telephone exchange serving as watchmens reporting stations, a central ofiice, means operable by the watchmen at said stations for extending talking connections therefrom to said central office in a definite order, means at said central ofiice for notifying the watchman that his call has been registered at the central oflice, and means at said central ofi'ice for preventing the watchman from receiving such notification when the connection is extended from a station not in the prescribed order.

NORMAN H. SAUNDERS. MORRIS E. GRIFFINS.