US2271653A - Divided multiplex channel - Google Patents

Description

Feb. 3, 1942. E. s. LARSON ET AL 2,271,653

DIVIDED MULTIPLEX CHANNEL Filed March' 15, 1939 3 Sheets-Sheet l INVENTOR. EDWARD S; LARSON ALBERT H. REIBER ATTORNEYS Feb. 3, 1942. s, LARSON ET AL 2,271,653

DIVIDEDMULTIPLEX CHANNEL Filed March 13, 1959 3 Sheets-Sheet, 2

s l n INVENTOR. EDWARD s. LARSON REIBER ALBERT H.

ORNEY:

Fb. 3,1942. E. s. LARSON Em 2, 71,6 3

DIVIDED MULTIPLEX CHANNEL Filed March 13, 1959 5 Sheets-Sheet 3 INVENTOR. EDWARD S. LARSON ALBERT H. REIBER Patented Feb. 3, 1942 DHIDED MULTIPLEX CHANNEL Edward S. Larson, Chicago, and Albert H. Reiber,

Evanston, Ill., assignors to Teletype Corporation, Chicago, 111., a corporation of Delaware Application March 13, 1939, Serial No. 261,444

20 Claims.

This invention relates primarily to a telegraph signaling system and more particularly to a system for transmitting messages concurrently from a variable number of transmitters over a single transmission path to a corresponding number of respectively related receivers.

An object of this invention is the transmission of concurrently stored messages one by one or part by part to several telegraph receivers in rotation.

Another object is the attainment of a continuous utilization of line time by the expedient of associating operatively with the transmission path only those receivers corresponding respectively to transmitters in which messages or parts of messages are stored and are awaiting transmission.

A still further object of this invention is to provide apparatus whereby a transmission path when assigned to a plurality of transmitters and associated receivers will be fully utilized by continuous transmission from a single transmitter to a single associated receiver whenever all other transmitters assigned to the path are idle or will be shared substantially equally between any two assigned transmitters when all other transmitters assigned to the path are idle, or will be shared substantially equally by all transmitters operating in rotation when all transmitters assigned to the path are in active condition.

A further object is to provide means responsive to signals transmitted over a first channel for selecting a substation and for qualifying it to record a message or a part thereof in combination with further means responsive to signals transmitted over a second channel for recording the message at the selected'and qualified substation.

Transmission paths mentioned above may be physical conductors, multiplex channels, radio channels or equivalent thereof.

To achieve the objects of this invention, means is provided for transmitting from a plurality of path sharing transmitters letter by letter in rotation, and for a modified method of operation, means is provided for transmitting line by line or message by message. As a provision for successful operation and for preventing any station from monopolizing the path, means is provided for limiting the length of time during which any station may occupy the path continuously without offering opportunity to other transmitters to seize the path, should one of the other transmitters be in active condition for transmission.

A more complete understanding of the invention may be had from the following description taken in conjunction with the accompanying drawings wherein:

Fig. 1 shows a circuit system for a transmitting station;

Fig. 2 shows a circuit system for a receiving station;

Fig. 3 shows a modified circuit system for a receiving station, and

Fig. 4 shows a modified circuit system for a transmitting station with message tenure limiting means.

Similar numerals refer to similar parts throughout the several views. Numerals 0 to 6, inclusive, are descriptive and are not to be taken as reference numerals.

In general, a transmission path is equipped at the transmitting end with a distributor of any type which connects the transmission path at all times to one of a plurality of transmitters assigned to that path. Transmitters are connected in rotation to the path. At the remote end of the'path a selector of any type responds to received recorder identification impulses and connects to the path the particular recorder associated with the then active transmitter. A message is recorded in a perforated tape and is transmitted from the tape. Recorder identification impulses may be sent from mechanism associated with the transmitter and are not necessarily transmitted from transmission tape. Limiting the tenure of a common path by any station or transmitter is accomplished by counting means operated by the transmitting means.

More specifically, there is illustrated in Figs. 1 and 2 jointly, a seven impulse system in which each character is transmitted by five character indicating combination impulses preceded by two recorder indicating combination impulses, the character indicating impulses being generated by a tape sensing device and the recorder indicating impulses being generated by contacts associated with the operating tape senser.

Referring to Fig. 1, a continuously driven power shaft Ill drives a start-stop cam sleeve H which carries rigidly fasten-ed to the sleeve four double lobe cams l2, l3, l4, and. I5, through a friction clutch, not shown. Each cam has two stop lugs 16 which on cams l2, I3, and I4 engage their armatures as I! respectively when the armatures are attracted, and which on cam I5 engage armature 18 when that armature is retracted. Armature I8 is bent laterally at its upper end toward cam IE to provide a lug which may be presented in the path of the lugs of cam l5 to arrest the cam, the body of armature I8 being positioned clear of the path of the lugs of cam I5. Each lobe operates a cam follower I9 and a number of electrical contacts associated therewith. Three tape sensers 2I, 22, and 23 are illustrated, each comprising a tape stepping magnet, five tape controlled tongues movable between two sets of five anvils, two resistors for limiting transmission currents, and a taut tape switch of well-known form. The tape sensers may be of a type illustrated and fully described in United States Patent No. 1,460,357 granted to E. E. Kleinschmidt.

A multiplex distributor 24 has five segments, collectively indicated by the numeral 25, which are connected by multiple branch conductors to five contact pairs 26 operable by cam I2 and to five similar contact pairs operable by cams I3, I4, and I5, respectively. The said contact pairs operable by cams I2, I3, and I4 are further connected to the tongues of tape sensers ZI, 22, and 23, respectively, while corresponding contacts operable by cam I are connected through a resistor to positive or spacing battery.

The distributor 24 has also two segments 21 and 28 for recorder identification signals. Segments 21 and 28 are connected to cam contact spring members 29 and 33 respectively, which, when in operated position, connect segment 21 through a resistor to negative or marking battery and connect segment 23 through a resistor to positive or spacing battery. When contacts of cam I2 are in unoperated position and contacts of cam I3 are in operated position, segment 21 will be connected through contact member 29 and contact member 3| and through a resistor to positive or spacing battery, while segment 28 will be connected through contact member 33 and contact member 34 to negative or marking battery. When contacts of cams I2 and I3 are in unoperated positions and contacts of cam I4 are in operated position, segment 21 will be connected through contact members 29 and 3 I, and segment 28 will be connected through contact members 33, and 34, and thence in common through contact members 32 and a resistor to negative or marking battery.

Distributor 24 has a continuous ring or feed ring 35 associated through brushes 3%! with segments 36 and 31. Segment 36 is connected through multiple branching conductors to the anvil of cam contact spring member 38 of cam I2 and to similar anvils of similar contact spring members of cams I3 and I4. When in operated position, each said cam contact spring member connects segment 36 over a local conductor to a terminal of one of the tape stepping magnets of tape sensers 2 I, 22, and 23, respectively, the other terminal of each said magnet being connected to negative battery.

Segment 31 is connected through winding of relay 4!! and a resistor to negative battery. Relay 40 when first energized disconnects positive battery from all holding circuits of magnets 44, 45, 46 to be described and connects positive battery in a testing circuit to discover all closed tape switches, through relay contact 4 I through winding of magnet 42 of cam I5, through all closed contacts of taut tape switches in tape sensers 2I, 22, and 23, through anvil and cam contact spring members 43 of cam I2 and through similar anvils and spring contact members of cams I3 and I4, all cam contact members being at that time transiently in normal or unoperated condition as will appear in description of operation of the system, and thence through all windings of cam magnets 44, 45, and 46 if all tape switches are discovered closed. When in normal or unoperated condition, the relay 40 connects positive battery through contact 41 to cam contact spring member 48 of cam I2 and by branching conductors to similar contact members of cams I3 and I4, thus forming a holding circuit for the cam magnet of any cam which is holding its contact members in operated condition, thus engaging members 43 and 48 and disengaging member 43 from its anvil.

In distributor 24, the collector ring 49 is connected to a line conductor 50 which extends to a distant station, Fig. 2.

Referring to Fig. 2 which illustrates a receiving circuit system to be associated with the transmitting system of Fig. 1, the line conductor 50 is connected through a line signal receiving relay 5I to ground. Contact members of relay 5| are connected to positive battery and to feed ring 53 of receiving multiplex distributor 54, the brushes of which are maintained in synchronism and in phase with the brushes of distributor 24 by any preferred means known in the art. Distributor 54 is provided also with feed ring 55, local segment 56, receiver indicating combinational segments 51 and 58 corresponding to segments 21 and 28 of Fig. 1, and five character indicating combinational segments 60 corresponding to segments 25 in Fig. 1.

Local segment 56 is connected through winding of starting relay 6| to negative battery. The armature of relay 6I is connected to positive battery, and the front contact point is connected through the winding of starting magnet 62 to negative battery. Segment 51 is connected through the winding of receiver selector relay 63 to negative battery, and segment 58 is connected through the winding of receiver selector relay 64 to negative battery. The five character combinational segments 60 are connected respectively through the windings of five code storage relays 65 to negative battery. Inner contact members of relays 63, 64 and 65 are connected to windings of the several relays and over a common conductor to the back contact point of starting relay 6I to form holding circuits for those relays, while outer contact members of relay banks 65 are connected to negative battery and to segments I to 5 of retransmitting distributor 66. Other connections of contacts of relays 63 and 64 will be explained in a description of operation to follow herein. Conductors 61, 68, and 69 may be local conductors connecting the selector relays 63 and 64 to three local receivers or printers H, 12, and 13, respectively, or may be extension line conductors connecting the central office selector relays 63 and 64 to three remote substation receivers H, 12, and 13.

Tape for each of the tape sensers 2|, 22, and 23 (Fig. 1) may be supplied by a reperforator con- I trolled by a transmitter at a remote substation,

as illustrated in connection with tape senser 2I wherein the tape 14 is supplied by a reperforator 15 operated by an electromagnet 16 controlled over a line conductor 11 by a substation transmitter 18. Reperforator 15 may be as illustrated and described in United States Patent 1,884,743 issued to E. E. Kleinschmidt, or of any other type desired. The transmitter 18 may be as illustratzcqlzand described in patent to Krum, No. 1,595,-

Operation of the system above described comprising Figs. 1 and 2 is as follows:

motion are approaching segments 21 and 28 while corresponding brushes 85 of receiving multiplex distributor 54, Fig. 2, are approaching corresponding segments 51 and 58.

Brushes 86 of distributor 54 have engaged segment 56 and have closed momentarily a circuit from positive battery through feed ring55, segment 56, and Winding of releasing and starting relay 6| to negative battery, energizing and operating the relay 6| momentarily, thus closing momentarily a circuit from positive battery through tongue and front contact point of relay 6| and winding of starting magnet 62 to negative battery, energizing magnet 62 and starting the brushes of distributor 66, which now are in motion.

On engagement of brushes 84 of distributor 24, Fig. l, with segment 21, a circuit will be formed momentarily from negative or marking battery through a resistor and cam controlled contact member 29, segment 21, collector ring 49, line conductor 56, and line relay 5| to ground, energizing relay 5| to hold its contact circuit closed. Immediately thereafter, brushes 85 in distributor 54 engage segment 51 and complete a circuit from positive battery through contacts of relay 5|, feed ring 53, segment 51, and winding of relay 63 to negative battery, energizing selector relay 63 which operates and forms its own holding circuit from negative battery through winding and inner-contacts of relay 63 and back contact and tongue of relay 6| to positive battery.

On engagement of brushes 84 of distributor 24 with segment 28, a circuit will be formed from positive or spacing battery through resistor and cam controlled contacts 33, segment 28, ring 49, line conductor 58, and line relay 5| to ground, en-

ergizing relay 5| to open its contact circuit. Im-

mediately thereafter, brushes 85 in distributor 54 engage and pass segment 58 without completing any circuit thus leaving selector relay 64 unenergized.

Selection of line 61 and recorder II now has been effected through contacts of operated relay 63 and unoperated relay 64, the circuit of line 61 now extending through top or outer closed contacts 86 of unoperated relay 64 and through top or outer contacts 8| of operated relay 63 to the feed ring of distributor 66 in preparation for transmission from contacts of storage relays 65.

Selection among lines 61, 68 and 69 is effected by permutational operation of selector relays 63 and 84, as follows: With neither selector relay operated, a condition which will be set up as a result of momentary energization of relay 6|, the three lines 67, 68 and 69 will be supplied with holding currents from negative battery through contacts of relays 63 and 64 in unoperated condition.

With selector relay 63 operated and relay 64 not operated, a condition which will be set up by receipt of current from segment 57 and no current from segment 58, when cam I2 is held by engagement with armature H, the line 61 will be seselected and will be connected to distributor 66 for transmission from contacts of storage relay set 65, while lines 68 and 68 will remain under control of holding currents. Circuit for line 61 extends through contacts unoperated, and contacts 8| operated to the collector ring of distributor 66, while circuit for line 68 extends through contacts 82 unoperated to negative battery and circuit for line 69 extends through contacts 83 unoperated to negative battery.

With selector relay 64 operated and relay 63 unoperated, a condition which will be set up by receipt of current from segment 58 and no current from segment 51, when cam I3 is held by engagement with the armature of magnet 45, the line 68 will be selected and will be connected to distributor 66 for transmission, while lines 61 and 69 will remain under control of holding currents. Circuit for line 68 extends through contacts 82 in operated condition and through contacts 81 unoperated to distributor 66, while circuit for line 61 extends through contacts 80 in operated condition to negative battery and circuit for line 69 extends through contacts 83 in operated condition and through contacts 8| unoperated to negative battery.

With both of the selector relays 63 and 64 operated, a condition which will be set up by receipt of current from both of segments 51 and 58, when cam I4 is held by engagement with armature of magnet 46, the line 69 will be selected and will be connected to distributor 66 for transmission, while lines 61 and 68 will remain under control of holding currents. Circuit for line 69 extends through contacts 83 in operated condition and through contacts 8| also in operated condition to distributor 66, while circuit for line 61 extends through contacts 88 in operated condition to negative battery and circuit for line 68 extends through contacts 82 in operated condition and through contacts 81 also in operated condition to negative battery.

Thus it is seen that any one of three extension lines 61, 68 and 69 may be selected by selective operation of only two selector relays taken one or two at a time, and it will be understood also that any one line in a group of lines not exceeding seven (2 2 2l) in number may be selected in like method by selective operation of only three selector relays taken one, two or three at a time, it being implied that with provision of three relays as 63 and 64 there would be provided also three segments as 51 and 58, three segments as 2? and 28, Fig. 1 and three sets of cam controlled contacts as 28 and 33 in each of the sets of contacts controlled by cams at I2, I3, I4, the provision of the added relays, segments and contacts now offering such a structure as will operate under control of seven cams such as I2, I3, I4, which would serve seven tape sensers such as 2|, 22', and 23. The flexibility of the system of the invention thus is implied in the herein embodied illustration showing but two selector relays.

Presuming that cam I2 is being held by armature I'I' so that line 61 has been selected, operation has been traced to an instant when brushes 84 and 85 are about to engage segments 25 and 60 respectively and when brush 13 in distribtuor 66 is about to engage the starting signal segment 88.

Now brushes of distributor 24 sweep over segments 25 completing five circuits from the five tape controlled tongues of tape senser 2| through five pairs of cam contacts 26 of cam I2, five segments 25, ring 49, line conductor 50, line relay 5| to ground, while synchronously the brushes of distributor 54 sweep over segments 68 and form in selective manner circuits for the energization of a code combination of storage relays of set 65. Each marking signal impulse closes the contact circuit of relay 5| through a segment 60 to energize a relay in set 65, while each spacing signal impulse opens the said circuit to leave a relay unenergized in set 65. Brushes 19 of distributor 66 complete a revolution, transmitting the signal code combination stored in the relay set 65 and stop in normal position under control of starting magnet 62. Thus, there has been completed the transmission to substation H of a code signal originated by transmitter l8 and stored in tape '14 until transmitted in rotational order over line conductor 54.

The cycle of code transmission operation is completed in the structure of Fig. 2 when brushes 86 engage segment 55, forming a circuit to energize the relay ti, unlocking relays 63 and 64 to release the used line and unlocking the relays of set 65 to delete the stored code signal, thus preparing the structure of Fig. 2 for receipt of an ensuing set of code signal impulses.

The cycle of code transmission operation is completed in the structure of Fig. 1 when brushes of distributor 24 pass segments 25 and engage segment 36. The used perforations of tape 14 are stepped out of the tape senser by operation of the stepping magnet of the tape senser which is energized by current from positive battery through feed ring 35, segment 36, operated cam contact member 38 and winding of the stepping magnet of the tape senser just used.

The next cycle of code transmission operation is begun in overlap manner, the distributor 66, Fig- 2 being still transmitting, when brushes 3!! in distributor 24 engage segment 31. Relay 40 is energized and operated over an obvious circuit disengaging contact 41 from positive battery and interrupting current in the holding circuit of cam magnet 44, deenergizing the magnet. The armature spring draws the armature of magnet 44 out of the path of lug l5, and a friction clutch, not shown, drives cam sleeve H and cams l2, 13, I4, and [5. Meanwhile, operated relay 40 has connected positive battery through contact 4|, winding of cam magnet 42, closed taut tape switches of tape sensers 2| and 23, anvils and cam contact spring members of cams l2 and I4, and

windings of cam magnets 44 and 46 to negative battery. Cam magnet 45 it not energized because the tape is taut and the taut tape switch is open in tape senser 22. Cam magnets 42, 44 and 46 are however operated. All of the cams thus rotate until the stop lug of cam l3 passes the unoperated armature of cam magnet 45 and until the stop lug of cam l4 engages the operated armature of cam magnet 48. At this time, cam I4 has moved its contact members into operated position interrupting the energizing circuit of cam magnet 46 which will be without current until 1 relay 42 supplies current in a holding circuit similar to the holding circuit described above for cam magnet 44. Cam magnets 42, 44, 45, and 46 are of slow-to-release construction, and cam magnet 46 retains its armature during this period. The brushes of distributor 24 now disengage from segment 3'! de-energizing relay 40, which releases its armature and forms a holding circuit for cam magnet 46 which alone is maintained energized.

The new cycle of code transmission operation continues as brushes 84 sweep over segments 21, 28 and 25 in the order of mention. Signal impulses will be generated by cam controlled contact set 32 and by contacts of tape senser 23, Fig. 1.

producing in the structure of Fig. 2 the conditions described in the paragraph above herein beginning, With both of the selector relays B3 and 64 operated. The perforated code signal sensed by tape senser 23 is transmitted to substation l3 and recorded there. The tape then is stepped in senser 23 by engagement of brush 3!! with segment 36 and in overlap manner the used line 69 is released and the used storage deleted from relay set by engagement of brush 86 with segment 56.

Presume for illustration that the tape step included in the first described cycle of transmission operation has opened the contact of the tape switch of tape senser 2|, leaving tape senser 23 as the only senser having a closed tape switch, then senser 23 will utilize the entire time of the multiplex channel.

Upon engagement of brush 39 with segment 31, at beginning a third cycle now to be described, with a sole closed tape switch, relay 49 becomes energized and operated. Contact 4'! is opened and de-energizes magnet 46. Contact 4| is closed to the armature contact member, closing a testing circuit to discover closed tape switches, which circuit under the presumed condition extends from positive battery through contact 4!, armature contact 99, winding of magnet 42, tape switch contact of senser 23 solely and terminates at the open contact of cam controlled contact set 9| which instantly is in operated condition as the last described cycle of code transmission was effected through contacts controlled by cam I4 and the armature 92 is instantly delayed by the structural limitations of magnet 46. Upon expiry of the delay period of magnet 46, the armature 92 retires and releases the cam l4 which permits the cam sleeve H to rotate and immediately the contact set 96 is returned to normalcy, extending the described testing circuit through contact set 9| and through winding of magnet 46 to negative battery, energizing both magnet 46 and magnet 42. Sleeve H now rotates, passes armature l8 because it is attracted, passes armature ll because it is not attracted, passes armature 93 because it is not attracted and stops on armature 92 now in attracted position. Brush 30 now disengages from segment 37, de-energizing relay 40 to form a holding circuit for magnet 46, and brushes 84 sweep over segments 2'7, 28, and 25, while brushes 35 sweep over segments 57, 58 and 63, accomplishing line selection in Fig. 2 and transmission of intelligence from tape senser 23, Fig. 1, to substation ?3, Fig. 2, in all details as in the second cycle above described, followed by clearance in the structure of Fig.2 through operation of relay ii and by tape step in senser 23 through engagement of brush 30 with segment 36. The described third cycle is repeated indefinitely, the senser 23 utilizing full time of the multiplex channel Should the tape of the sole opening senser 23 become taut, thereby opening the contacts of the tape switch of that senser and rendering all tape switch contacts open, then described testing circuit for detection of closed tape switches would extend from positive battery through contacts 4! and 9E and winding of magnet 42 and would stop at open contacts of all tape switches. Upon expiry of the delay period of magnet 46, the armature 92 retires and releases the cam l4 which permits cam sleeve H to rotate, the cam sleeve being stopped by engagement of cam 55 with unattracted armature E8 of unenergized magnet 42. At each revolution of brush 36 the relay 40 will be operated but no energizaticn of magnet 42 will occur so long as all tape switches remain open, and cam sleeve I I will not rotate.

Obviously, upon provision of slack tape in senser 23 the conditions for the above described third cycle will be set up, and by provision of slack tape in all sensers the cam sleeve H will rotate at each release to the next stop position, thus serving all stop positions and all tape sensers in uniform rotation.

Arbitrary constants suitably related in the dimension of time for operation of elements involving periods of delay may be noted as follows: Brushes of distributors 24 and 54, 300 revolutions per minute or .20 second per revolution. Cam sleeve I I, 1,500 revolutions per minute or .04 second perrevolution and .005 second from stop position to stop position. Segment 36 circuit is closed .01 second. Segment 31 circuit is closed .04 second. Delay of armature I1 after cessation of current in magnet 44 is .02 second. As a modified form of the invention, there is illustrated in Figs. 3 and 4 jointly an 8-impulse system embodying three novel features; namely, provision of three receiver indicating combinational impulses, provision of means for transmission line by line, and provision of means for limiting tenure of the line.

Referring to the modified structure illustrated in Fig. 4, a continuously driven power shaft H drives a start-stop cam sleeve III which carries four double lobed cams H2, H3, H4, and H5, through a friction clutch, not shown. Each cam has two stop lugs H6, which on cams I I2, H3, H4 engage armatures I I1, respectively, when attracted and which on cam I I5 engage armature H8 when that armature is retracted. Each lug operates a cam follower H3 and a number of electrical contacts associated therewith. Three tape sensers I2I, I22, and I 23 are illustrated, each having component parts as tape senser 2| Fig. 1.

A multiplex distributor I24 has five segments collectively indicated by numeral I25 which are connected by multiple branches to five contact pairs I26 operable by cam I I2 and to five similar contact pairs operable by cams H3, H4, and H5, respectively. The said contact pairs are further connected as in Fig. 1.

The distributor I24 also has three segments I21, I28, and I29 for receiver identification signals. Segment I21 is connected to cam contact spring member I30 which, when in operated position, is connected through a resistor to negative or marking battery and when in normal or unoperated position, is connected through a resistor to positive or spacing battery.

Segment I28 is connected to cam contact spring member I3! and segment I29 to spring I32 which springs operate under control cams H3 and H4 as does spring I30 under control of cam Distributor I24 has a feed ring I35 associated through brushes with segments I36 and I31. Segment I36 is connected through multiple branching conductors to anvil of contact spring member I38 of cam H2 and to similar anvils of similar contact spring members of cams I I3, I I4. When in operated position, each said cam contact spring member connects segment I36 over a local conductor to terminals of magnets of tape sensers I2I, I22, I23, respectively, the other terminal of each of said magnets being connected to negative battery. Segment I36 is connected also through winding of counting magnet I39 to negative battery. Segment I31 is connected through winding of relay I40, through contacts of code relays I33 and through a resistor to negative battery. Re-

lay I40, when in normal or unenergized condition, connects positive battery through a branching conductor to cam controlled contact elements as I48, which, when operated, engage a contact element as I43 and extend the circuit through a cam magnet as I44, I45, or I46, thus forming a holding circuit for an energized one of said magnets for which the cam follower I I9 is in operated condition. Relay I40, when energized, connects positive battery through winding of the magnet I42 of cam I I5 through all closed contacts of taut tape switches in tape sensers I2I, I22, and I23, and through cam contact members I 43 and corresponding cam magnets to negative battery. A further contact of relay I40 connects positive battery to winding of slow-to-operate relay MI and through a resistor to negative battery when relay I40 is in operated condition.

A ratchet segment I is attached or articulated to a striking member I5I which in normal or restored position, as shown, engages and holds apart a pair of contacts I52 and which in its fully operated position engages and pushes together a pair of contacts I53. About'10 steps of ratchet I50 representing a maximum of 70 characters in a printed line, are required to move member I5I from contacts I52 to contacts I53. Magnet I39 is provided with an armature I54 which carries a pawl I55 to drive the ratchet I50 in cooperation with a detent pawl I56. Pawl I55 is at the same time an armature member of magnet I40, and upon energization of magnet I40, the pawl I55 is withdrawn from the ratchet, engaging and withdrawing also the detent pawl I56, to permit return of the ratchet by a spring, not shown, to its unoperated position. An energizing circuit for magnet I40 includes ring I35, segment I31, winding of I 40, and contacts I53. A holding circuit for magnet I40 includes contact member I51, winding of I40, contact member I58, and contacts I52.

Apparatus illustrated in Fig. 3 duplicates apparatus illustrated in Fig. 2 except that segments 51 and 58 are replaced by segments I61, I68, I 69, and that relays 63 and 64 are replaced by relays I13, I14, and I15.

Operationof the modified system illustrated in Figs. 3 and 4 is similar to the operation of the system illustrated in Figs. 1 and 2 except in the details of selecting a substation and of abandoning a used transmitter.

In, condition shown, with slack tape in tape sensers I2I, I23, and with taut tape in tape senser I22, the system will function to transmit messages line, by line alternately from tape sensers I2I and I23. Magnet I44 is shown energized, with its armature in operated condition, and cam H2 is holding its electrical contact members in operated condition. Brushesof distributor I54 have passed segment I66, energizing relay I'II momentarily, which has provided current to energize magnet I12 momentarily to start the brushes of distributor I15. On engagement of brushes of distributor I 24 successively with segments I21, I28, and I29, one marking impulse and then two spacing impulses will be transmitted over line I and through relay NH and distributor I64 andwill be received by relays I13, I14, and I 15, energizing relay I13 alone, which forms its holding circuit to contacts of relay I 1I and which switches substation I8I and line I11 to the ring of commutator I16. Brushes of distributors I24 and I64 now sweep over segments I25 and I10, respectively, transmitting a character code signal into storage relays of set I65, which code signal is retransmitted by distributor I16 through contacts of relay I13 to substation or printer I8I. Brushes of distributor I24 now engage segment I36 stepping the tape in the operative senser I2I, also energizing magnet I39 to step ratchet I50 without result until its 70th step is made. Brushes of distributor I24 then engage segment I31, but without efiect as the circuit of magnet I40 is instantly open at all points. Brushes of distributor I64 then engage segment I66, energizing relay I1I, releasing the relay I13, and energizing magnet I12 to restart the distributor I16 after which the relay I13 and station I8I are reselected, and this reselection occurs before transmission of every code signal for that substation.

With a page printer home recorder at substation 18, Fig. l, the operator will use a carriage return code signal at the end of each line, which signal will appear in the tape at the reperforator 14. With similar carriage return signals in the tape of senser I2 I, transmission from such a signal having only the No. 4 impulse of marking nature will control armatures of relays I33 to close a circuit from negative battery and resistor to winding of relay I48, which, by engagement of distributor brushes with segment I31, will complete a circuit to energize that relay which forms its own locking-circuit, as described above, and by its armature I85 opens holding circuit of magnet I44 and closes a selecting circuit through winding of magnet I42, closed contacts of tape switches of sensers I2I and I23, cam contacts as I43, and magnets I44 and I46. Armature of magnet I 46 engages cam H4 and stops the cam sleeve II I, armature of slow to operate relay I4I engages its contact and closes a preliminary holding circuit for magnet I46. Energization of magnet I40 has withdrawn pawl I55 and detent pawl I56 from ratchet I50, and striker I5I returns under power of a retractile spring, not shown, to engageand open the contacts I52, thus de-energizing the magnet I40, the armature members of which now form the ultimate holding circuit for magnet I46, and also de-energize the relay The carriage return code signal in tape senser I2! which has caused the abandonment of tape senser I2I has not been transmitted, but will be transmitted when tape senser IZI is used again. Since complete return of striker I5I is required to release amature member I85 of magnet I40, the relay I4I is provided to form a preliminary holding circuit for magnet I46. Relay MI is slow enough to permit the cam sleeve III to make a complete revolution before any holding circuit is closed.

After the advance of cam sleeve III, distributors I24 and I64 will transmit two spacing impulses and then one marking impulse from cam contact members I30, I3I, and I32 severally, energizing relay I15 alone, after which distributor I16 transmits code signals through contacts of relay I15 to substation I83 which is coordinated with tape senser I23.

In case a sub-station apparatus as 18 controlling the operation of perforated tape for a tape senser as I2I should be of tape printer type rather than of page printer type, no code signal for carriage return would be produced for control of relays I33. In such case, transmission from tape senser I2I will proceed until striker I5I engages contacts I53 and presses them together producing the electrical equivalent of closed contacts in relays I33. When brushes of distributor I24 engage segments I31 with contacts I53 closed, relay I40 is energized over the obvious circuit and looks over the described holding circuit thus advancing the cam sleeve I I I and resetting the ratchet segment exactly as described in response to operation of coded contacts of relays I33. In case of error or accident as breaking of any tape so that a carriage return code signal is not presented to the tape senser, the contact I53 will operate to relieve the situation by advancing the cam sleeve I I I.

Cam sleeve III when started will stop, as described in connection with apparatus of Fig. 1, by engagement of a cam member with an armature such as H1 in attracted position or by engagement with armature H8 in retracted position should all tape switch contacts be open. In the latter event, brushes I30 at each revolution will engage segment I36 and will energize magnet I39 which will step the ratchet I50, ultimately closing contacts I53 which will permit brushes I30 while in engagement with segment I31 to energize and operate relay I40 but magnet I42 will not be energized and cam III will not start because all tape switch contacts are open. When any tape becomes slack and transmission is resumed as described in connection with Fig. 1, the ratchet I50 will be in position at random and thereafter may start cam sleeve III before receipt of a carriage return code signal but without detriment to the service being rendered.

The invention has been described in connection with specific illustrative systems which are capable of modification without departing from the spirit or scope of the invention, the invention being described by the scope of the appended claims.

What is claimed is:

1. The method of operating a telegraph system which comprises the steps of selecting a destination for a message by transmitting a permutation code signal over a communication channel, transmitting a permutation code signal representing a character of the said message over another channel, and repeating the described two steps for each character of said message.

2. The method of operating a telegraph system which comprises the steps of selecting a destination for a message by transmitting a permutation code signal representing a permutation callingcode signal for said destination, thereafter transmitting a permutation code signal representing a character of the said message and repeating the described two steps for each character of said message.

3. The method of operating a telegraph system which comprises the steps of selecting a destina tion for a message by transmitting a permutation code signal over a communication channel, transmitting a permutation code signal representing a character of the message over another channel to the selected destination, and repeating the described two steps for each character of said message.

4. The method of operating a telegraph system which comprises the steps of selecting a destination for a message by transmitting a permutation code signal representing a permutation callingcode signal for said destination, thereafter transmitting a permutation code signal representing a character of the message to the selected destination, and repeating the described two steps for each character of said message.

5. The method of operating-a telegraph system which comprises the operations of transmitting over two telegraph channels respectively, a permutation code signal representing a character-to be printed and a single signal impulse in predetermined time relation to the transmission period of the said code signal, selecting a destination by control of said single signal impulse, retransmitting said transmitted permutation code signal to said selected destination, and repeating the described operations for each character of the message.

6. In a telegraph system, a first multiplex communication channel, a second multiplex communication channel, a plurality of recorders, means responsive to a combination code signal individual to each of said recorders over said first channel to select and to condition one of said recorders for'operation, and means responsive to combinational code signal impulses over said second channel to operate the recorder conditioned for operation.

7. In a telegraph system, a multiplex communication channel, a plurality of recorders, means responsive to combination code signal impulses over said channel embodying a permutation calling-code signal individual to one of saidrecorders to select and condition said one of said recorders for operation, means responsive to a signal combination code signal of impulses over said channel to operate said selected recorder, and means to deconolition said recorder invariably after a single operation thereof.

8. In a multiplex transmitting station apparatus, a rotary switching device having a plurality of stop positions, means in said switching device operable in each stop position of the device for transmitting into a multiplex channel a signal individual to each of said stop positions, and further means at said transmitting station for transmitting into a different multiplex channel through said switching device in its then occupied stop position a permutation code signal of message nature.

9. In a multiplex transmitting station apparatus, a rotary switching device having a plurality of stop positions, and means in said switching device operable in each stop position of the device for establishing and transmitting into a multiplex channel a signal individual to and definitely identifying each of the said stop positions.

10. In a multiplex transmitting station apparatus, a multiplex destributor, a rotary switching device having a plurality of stop positions, means in said switching device operable in each stop position of the device for establishing and transmitting to said multiplex distributor a signal individual to the said stop position, further means for transmitting to said multiplex distributor under control of said switching device a code signal of a message, and starting means for said rotary switching device controlled by said multiplex distributor to start said rotary device after trans- 12. In a multiplex transmitting station apparatus, a switching device having a plurality of positions and a plurality of contacts, means in said switching device operable in each position of the device for transmitting into a multiplex channel a signal individual to each of said positions, and further means at said transmitting station for transmitting through contacts of said switching device in its then occupied position a permutation code signal of message matter.

13. In a telegraph transmitting station apparatus, a rotary device, stop means for said rotary device adapted to stop said rotarydevice in a specific angular position, switching means operated by said device in said specific position to connect to a multiplex channel a specific permutation transmitter of variant code signals, and further means in said device to connect to a further multiplex channel a permutation transmitter of an invariable code signal individual to that specific stop position of said rotary device.

14. In a telegraph transmitting station apparatus, a plurality of transmitters, a rotary device, stop means for said rotary device adapted to stop said rotary device in a specific angular position, switching means operated by said device in said specific position to connect to a multiplex transmitting distributor a specific permutation transmitter of variant code signals, and further means in said device to connect to said multiplex distributor a transmitter transmitting invariably a specific code signal individual to said specific angular stop position.

15. In a telegraph transmitting station apparatus, a rotary device, a plurality of stop means to stop said device in a plurality of stop positions respectively, a plurality of permutationcode variable-code signal transmitters associated respectively with stop positions of said device, switching means for said device operable in each stop position of said device to connect to a multiplex channel that one of said transmitters which is identified with the said stop position, and code means in said device operable in each stop position to transmit to a further multiplex channel a permutation code signal invariable for each stop position of said device and variant among all stop positions of said device.

16. The method of operating a telegraph system which comprises the steps of selecting a destination for a first message by transmitting a permutation code signal over a communication channel, transmitting a permutation code signal representing a component part of the first message over another channel, repeating the described two steps for a plurality of component parts of the first message, then transmitting a predetermined code signal representing a component part of the first message and effective also to indicate the end of the message, and following with said first two steps in alternation, but with selection of a different destination.

17. The method of operating a telegraph system which comprises the steps of selecting a destination for a message by transmitting a permutation code signal over a communication channel, transmitting a permutation code signal representing a component code'signal of the message over another channel to the selected destination, and repeating the described two steps for each component code signal of a message to one destination and continuing the described two steps over the same two channels but to a difierent destination repeatedly.

18. In a multiplex transmitting station apparatus, a plurality of transmitters, a switching device having a plurality of positions, means in said switching device operable in each position of the device for connecting one of said transmitters to a multiplex channel, and counting means at said transmitting station responsive to transmission of a preset number of code signals for changing said switching device to another one of said transmitters.

19. In a telegraph transmitting station apparatus, a plurality of transmitters, a rotary device, positioning means for said rotary device adapted to position said rotary device in specific angular positions, switching means operated by said rotary device in said specific positions to connect to a multiplex channel diflferent ones of said transmitters in rotation, and counting means operative upon transmission of a preset number of code signals to connect another of said transmitters to said multiplex channel.

20. In a telegraph transmitting station, a counting device operative upon transmission of a code signal, a stepping device, a plurality of transmitters, means in said stepping device to qualify one of said transmitters for transmitting selectively according to the instant position of the stepping device, and means in said counting device for advancing said stepping device out of its instant position effective upon attainment of a specific condition in said counting device.

EDWARD S. LARSON.

ALBERT I-I. REIBER.

Images