US2082550A

US2082550A - Centralized traffic controlling system for railroads

Info

Publication number: US2082550A
Application number: US682829A
Authority: US
Inventors: Winfred T Powell
Original assignee: General Railway Signal Co
Current assignee: SPX Corp
Priority date: 1933-07-29
Filing date: 1933-07-29
Publication date: 1937-06-01
Anticipated expiration: 1954-06-01

Description

w. T. POWELL 2,082,550

CENTRALIZED TRAFFIC CONTROLLING SYSTEM FOR RAILROADS June 1, 1937.

Filed July 29, 1933 2 Sheets-Sheet 1 him '. INVENTOR BY W.T. Powell,

MZZZZdS H IS ATTORNEY.

- June 1, 1937. w, T, POWELL 2,082,550

CENTRALIZED TRAFFIC CONTROLLING SYSTEM FOR RAILROADS Filed July 29, 1933 2 Sheets-Sheet 2 V'L'Id k Ev 33% 3i i Q 9. Q n. 2 I41 "I r \9 o I"! W V q 3 w 6 W 2 '1" U N L I INVENTOR Ll. WT Powell,

HIS ATTO-RNEY.

Patented June 1, 1937 UNITED STATES CENTRALIZED TRAFFIC CONTROLLING SYSTEM FOR RAILROADS Winfred '1. Powell, Rochester, N. Y., assignor to General Railway Signal Company, Rochester,

Application July 29, 1933, Serial No. 682,829

14 Claims.

This invention relates to centralized traflic controlling systems for railroads and it more particularly pertains to means employed for interrelating the operation of a plurality of traffic controlling devices with the operation of the communication part of such a system.

In that type of centralized trafiic controlling system where a communication system of the station selective type is employed, control impulses are transmitted from the central control oflice to the several field stations during separate operating cycles. Similarly, indication impulses are transmitted to the control oilice in accordance with the positions of the various trafiic controlling devices at the several field stations and these indication impulses are transmitted to the control office, one station for each operating cycle. Since the present invention is directed to the transmission of controls from the control ofiice to the various field stations, the indication portion of the centralized trafiic controlling system is not disclosed.

The invention more specifically embodies means for associating a plurality of stored start conditions with the communication system in the order in which these start conditions are stored. For example, the operator in the control office may operate the three keys or starting buttons I53, 283 and 383, shown in Fig. l, in any desired order and in accordance with the present invention the associated stations will be selected in accordance with the order of operation of these buttons. In former systems of this type the starting buttons associated with the various field stations were actively associated with the communication system in the order of their location or connection in the code determining relay bank.

In view of the above and other considerations, the present invention proposes to provide means whereby the efiect of several changed conditions in the control ofiice, as determined by the operation of several starting buttons, may be suitably stored with the storing means becoming actively associated with the communication system, one at a time, and in the exact order of operation of the starting buttons.

Other objects, purposes and characteristic features of the present invention will be in part obvious from the accompanying drawings and in part pointed out as the description of the invention progresses.

In describing the invention in detail reference will be made to the accompanying drawings, in which:

Fig. 1 illustrates three keys or startin buttons and the associated relays which cooperate in associating these keys with the communication system in the order of operation.

Fig. 2 illustrates the manner in which the polar impulses are selectively applied to the communication line circuit as determined by the particular code determining relay. which associates the line circuit with the synchronous stepping relay bank by way of the code jumpers and lever devices.

A centralized trafiic controlling system organized as contemplated in accordance with the present invention is considered to comprise a control omce located at a convenient point and a plurality of field stations located throughout the territory under the control of the operator. The communication system connecting the control office with these field stations may be of any suitable type, but for convenience in describing the present invention, it is assumed that such a communication system is of the station selective duplex coded type as disclosed, for example, in the pending application of T. J. Judge, at al., Ser. No. 640,062 filed October 28, 1932, corresponding to British Patent 419,399. It is to be understood, however, that the specific form of a communication system is not essential to the functioning of the means embodying the present invention, but rather the means embodying the present invention may be considered as an adjunct to any communication system.

In.the communication system contemplated, as used in connection with the present invention, a' series stepping or control line circuit connects the control office with the several field stations and receives current impulses from a suitable source of energy located in the control oflice. This line circuit is indicated in the lower right-hand portion of Fig. 2 by reference charactors l0 and I2 which correspond to like reference characters in the above-mentioned prior application Ser. No. 640,062. A series message or indication line circuit likewise connects the control oflice with the various field stations but, as above mentioned, this portion of the system has been omitted from the present disclosure.

Slow acting relays SA and 28A of Fig. 2 correspond to relays SA and ZSA of the abovementioned prior application, and it will be understood that these relays are used to define the bounds of an operating cycle, that is, they are picked up at the beginning of a cycle and dropped at the end of the cycle.

Stepping relays IV, 2V, and 3V, as well as control cycle relay C, correspond to similar relays in the above-mentioned prior application. Likewise, line relay F, impulse relay EP, positive code determining relay PC and negative code determining relay NC, with their associated contacts, correspond to similar relays and contacts in the above-mentioned prior application.

Starting buttons or keys ISB, ZSB and 35B are provided for the purpose of initiating the communication system into cycles of operations for selecting corresponding ld stations. Change relays ICH ICH and ICH are associated with starting button ISB, these relays being selectively operated in accordance with the operation of the associated starting button and in accordance with the sequence of operation of this button. In other words, if when the communication system is in its normal-at-rest condition, starting button ISB is actuated before any of the other starting buttons, relay ICH will be picked up and stuck up. If button ISB is the second button actuated in a rapid sequence of operations, following the actuation of one of the other starting buttons, then relay ICH will be picked up and stuck up. If button ISB is the third button operated in the sequence of rapid actuations of the starting buttons following the actuation of two of' the other starting buttons, then relay ICH will be picked up and stuck up. Similarly, if button ISB is actuated three times in succession, relays lCH lCl-I and ICH will be picked up in rotation and as will be later described the communication system will select the station associated with button ISB three times in succession.

Change relays 2CH 2CI-I and ZCH are asso ciated with starting button 28B and these relays are picked up and stuck up as determined by the sequence in which button ZSB is actuated. For example, if button B is the first one actuated with the system at rest, then relay ZCH is picked up and stuck up. If button 283 is actuated second in turn then relay ZCH is picked up and stuck up. If button 25B is actuated third in turn then relay 20H is picked up and stuck up.

Relays 3CH 30H and 30K are selectively actuated in the order of actuation of button 383 in the same manner as described for the other two buttons. It will be understood that a system of larger capacity than that indicated in Fig. 1 will make use of the same principle of operation of the added buttons and change relays. For each starting-button and associated station added to the system a set of change relays is provided, the number of which equals the number of total starting buttons. This means that for each starting button added an additional change relay is added to each group shown in Fig. 1.

Sequence determining relays ISD, 28D and B are common to all change relays and are for the purpose of selecting the particular relay associated with a particular starting button as determined by the sequence in which that starting button is actuated. With the system in its normal-at-rest condition, relays ISD, 2SD and 38B are deenergized so that the first change relay of each series is selected for operation when an associated starting button is actuated. After this first actuation relay I SD picks up and extends the selecting circuit to the second change relay of all the groups, so that the next starting button actuated picks up the second change relay in the associated group. After this second operation relay 2SD is picked up and the third change relays of each group are selected, so that the actuation of the next or third starting button picks up the third change relay of the associated group. This order of operation is followed for as many steps as required as determined by the capacity of the system.

Code determining relays ICD, 2CD and 3CD correspond to similarly characterized relays in the above-mentioned prior application. These relays are picked up only one at a time during a cycle of operations for determining the character of the impulses applied to the communication circuit for selecting the required station and circuits for conditioning the control devices as determined by the position of the control le- 'vers (such as levers ISML, ZSML and 3SML) associated with the particular code determining relay which ispicked up.

A set of code jumpers, such as 40, and 58, corresponding to similar jumpers in the abovementioned application, select the polarity determining relays PC and NC in difierent combinations, as determined by code determining relay ICD being picked up during an operating cycle. Each code determining relay has a corresponding set of code jumpers connected in different combinations, as shown in Fig. 2. Contacts 62, I3 and 32 of relays ICD, 2CD and 3CD, as well as any other necessary contacts on these relays, selectively operate the polarity determining relays .PC ,and NC as determined by the positions of various lever devices selected by these contacts.

The impulses applied to the control line circuit are governed by relays PC and NC, the line circuit being energized by control battery CB. The interruptions of the energized line are provided by impulse relay EP picking up its back contact 52, all of which is completely disclosed and thoroughly discussed in the abovementioned prior application Ser. No. 640,062.

Instead of showing the actual connections to the terminals of suitable sources of potential, symbols have been employed to represent such terminals. The symbols and designate the opposite terminals of a suitable source of potential and the circuits with which these symbols are employed always have current flowing in the same direction.

It is believed that the operation and usefulness of the present invention will be best understood by further description being set forth from the standpoint of operation.

OPERATION Normal conditions With the system normally-at-rest all of the relays indicated in Fig. l and Fig. 2 are in their deenergized conditions. In order that the communication system may be initiated into operation from the control office, the upper windings of relays ICH 2CH and 3CH have minus potential applied thereto so that the actuation of any one of the starting buttons will pick up the corresponding one of these first change relays of each group.

Manual starting With the system in a condition of rest, or period of blank, it may be manually initiated into a cycle of operations for the transmission of controls to any desired station. Whenever such a cycle of operation is desired the operator first positions the control levers of that particular station with whichhe' desires to con-' meet and then actuates the corresponding start- I are provided so that the code call of only onestation is transmitted during any one particular cycle of operations and this particular station will be the one which corresponds to the first buttonactuated'; If severalbuttons are simultaneously actuated then, due to the connections starting at button ISB and'extending in series to the other starting buttons through back contacts, only button ISB is effective. In other words, itis necessary to operate the starting buttons in a sequential order restoring one before the next is actuated in order to sequen-v tially store the conditions requiring the selection of more than one station.

This feature is provided by the interlocking arrangement of the sequence determining relays and the change relays The sequence between control operations following the actuation of a number of starting buttons is more conv'eniently discussed by assuming the actuation of the three buttons illustrated in a particular orderor sequence. It will be assumed that the three buttons are operated in order 3, 1, 2. The system, will, therefore, record this order of operations and transmit to stations 3, 1 and 2 in rotation.

The actuation of button 383 closes a circuit for picking up relay 3CH 1 extending from back contact 3 of button ISB, back contact I of button ISB, front contact ii of button ISB, upper winding of relay 30H back contact 10 of relay lSD,back contact ll of relay 28D and back contact 12 ofwrelay 38D to Relay 30H closes a stick circuit for itself extending from front contact 63 and lower winding of relay 30H and the lower winding of relay ISD to Although the current which energizes and sticks relay 3CH 1 by way of its lower winding comes through the lower winding of relay ISD, this latter relay is not picked up at this time because current is flowing through its upper winding in opposition to that in its lower winding over a circuit which extends from resistance unit RS, back contact 4 of button ISB, back contact Bof button 2 SB, front contact i6 of button 35B, front contact 64 of relay 30H back contact 65 and upper winding of relay ISD to Since the value of resistance unit RS is approximately the same as the value of the lower winding of relay 3CH the current flow through the two windings of relay iSD is approximately equal and since these two windings are differentially connected the relay is not actuated.

When the operator restores button 383 to normal, however, relay iSD is actuated by means of the current-flowing through its lower windingalone, due to the fact that the current through its upper winding isinterrupted when front contact N of button 353 is opened. The actuation of relay ISD opens the circuit through its upper winding at back contact 65 so that the upper winding will not receive current upon another; actuation of button 383. At this time, relays 3CH and lSDare stuck up by current flowing throhghtheir lower windings in series.

When button 183 is ,actuated the only TCH relay which gets current is relay ICH since the potential as selected by chum-1|; 1| and 12 of the sequence determining relays "is now connected-to the upper winding of only relay ICH of this series. Relay lGI-I- is picked up over a circuit extending from front contact 2 of button ISB, upper winding of relay ICH front contact ll of relay ISD, back contact ll of relay ISD, and back contact ll of relay 38D to Relay 'ICH closes a stick circuit for itself extending from front contact 13 and lower winding of I relay ICH 2 and the lower winding of relay 2SDto Relay ISD is not picked up'at this time because of the current flowing through its upper winding which is equal and opposite to that through'its lower winding. This circuit extends from resistance unit RS, front contact 4 of button ISB, front'contact 14 of relay ICH back contact 15 of relay 28D, and the upper winding *of' relay 28D to when button ISB is restored to normal the current through the upperwinding of relay ZSD- is interrupted at front contact 4 of button ISB, which allows this relay to be actuated by means of the cur-. rent flowing through its lower winding alone. Relays I OH and 28D are now energized through the lower windings in series. I

When button 25B is actuated'the only relay in the second series which gets'current is relay 20H The circuit for picking up relay ZCH extends from back contact I of button I SB, front contact 5 of button 283, upper winding of relay ICH front contact ll of relay 28D and back contact 12 of relay 381) to Relay ICH closes a stick circuit for itself extending from front contact 16 and lower winding of relay 20H and the lower winding of relay 38D to Relay 38D is not picked up .at this time, because of an equal-and opposite effect in its upper winding due to current flowing over a circuit extending from resistance unit RS, back contact 4 of button ISB, front contact 8 of button 283, front contact ll of relay 2C1! back contact 18 and upper winding of relay ISD to When button 283 is restored to normal the circuit through the upper winding of relay 38D is interrupted at front contact 8 of button ISB so that relay ISD is actuated by means of the current which flows through its loweif winding alone. Relays 2CH 3 and 33B are nov; energized through their lower windings in series.

Polarity selection and transmission a I The communication system is initiated from the control oflice when any change relay is picked up. The picking up of a change relay is effective to pick up a common change repeating relay (not shown) which in turn picks up the control cycle relay C to mark this cycle as one for the transmission of controls. Since this particular part of the operation of the system isimmaterial toan understanding of the present invention, and since the system may be initiated in any desired manner, these detailed circuits have been omitted. 'One example 'of'the manner in whichthe system maybe initiated into acycle of operations, as a result of one or more change relays being picked up; is disclosed in the above-mentioned prior application Ser; No. 640,062. It be recalled that inthe assumed example, relays ICH, I CH and'ZCH were picked up in the order named andjstuck up. A Also, re-

The only code determining relay which can be picked up, at this time, is relay 3CD picked up over a circuit extending from front contact 66 of relay ISD, front contact I of relay ICH and winding of relay 3CD to Although all three sequence determining relays are picked up at this time, the energizing circuits for the other code determining relays are interrupted at back contact 66 of relay ISD.

The impulses placed upon the line circuit for the succeeding cycle of operations are of polarities determined in accordance with the positions of the code jumpers and the control levers rendered effective by the picking up of relay 3CD. As soon as relay ICD ispicked up following the energization of relay C, one or the other of the polarity control relays PC and NC is energized depending upon the position of the first code jumper.

More specifically, if code jumper II is in the position illustrated, relay NC is energized. but if this code jumper is in its dotted line position, relay PC is energized. For example, assuming code jumper III to be in the position illustrated, the circuit for energizing relay NC extends from front contact ll of relay C, back contacts 42, 43 and 44 of relays 3V, IV and IV, respectively, front contact Ii of relay 3013, code jumper I0, negative bus 48 and winding of relay NC to 1 The energization of relay NC applies a negative impulse to the control line circuit including conductors l0 and II. It is apparent, that code jumper II, in its alternate or dotted line position, causes the energization of relay PC which applies a positive impulse to the line circuit. Assuming, that relay PC is energized, the control line is energized from the positive terminal of battery CB over a circuit including back contact -50 of relay NC, front contact SI of relay PC, back contact 52 of relay EP, winding of line relay F, control line wire II, and through the various field station line relays in series to the return conductor II, andthence through front contact 53 of relay PC and back contact 54 of relay NC to the negative terminal of battery CB.

In the event that relay NC is energized, then contacts 50 and 54 of this relay reverse the connection from battery CH to the line circuit so that an impulse of negative polarity is ap plied to line conductor II. The energization .of

line relay F and the subsequent deenergization of the control line circuit by relay EP, results in the picking up of stepping relaylV, all in a manner explained in the above-mentioned prior application.

One or the other of the polarity control relays PC and NC will now be energized, as determined by the position of code jumper 30. Assuming jumper to be connected as illustrated in Fi 2, relay NC is energized over a circuit extending from front contact ll of relay C, back contacts 42 and 43 of relays 3V and IV. respectively, front contact 44 of relay IV, front contact II of relay ICD, code jumper II, negative bus ll and winding of relay NC to When the system takes its next step, a circuit is completed for energizing relay PC, which extends from front contact ll of relay C, back contact I of relay IV, front contact 43 of relay IV, front contact 23 of relay ICD, code jumper ll, positive bus 41 and winding of relay PC to It will be obvious that the jumpers II, II and Ii connected as shown cause a code of to be applied to the line for selecting the station corr to this code and associated with relay ICD.

When the system takes its next step by picking up relay IV, either relay PC or NC is energized over a circuit extending from through front contact ll of relay C, front contact I of relay 3V, and front contact 'II of relay ICD to positive code bus 41 or negative bus II, as selected by control lever ISML which is associated with contact II of relay ICD.

At the end of this cycle of operations, relay 8A is dropped which deenergizes the winding of relay ISA by the dropping of front contact II. During the interval between the dropping of relay SA and the dropping of relay ISA, a circult is effective to deenergize relay ICE and to maintain relay ISD energized. This circuit extends from back contact II of relay SA. front contact 34 of relay ISA, conductor I5, front contact I. of relay ISD to the right-hand terminal of the lower winding of relay ICH Since the left-hand terminal of this winding is connected to by way of front contact I of relay 3011 and since the upper winding of this relay is open, the effect of short circuiting the lower winding causes its release. This circuit from at back contact 33 of relay SA also extends through the lower winding of relay ISD to and since the upper winding of this relay is deenergized at this time, it remains in its actuated position.

When relay ISA drops its front contact 34, conductor is deenergized, which deenergizes the lower winding of relay ISD allowing this relay to drop its contacts. Another cycle will be immediately started because it has been assumed that relay iCl-F is picked up. This cycle will be effective to select station I as determined by relay ICD being picked up over a circuit extending from back contact I of relay ISD, front contact 69 of relay ISD, front contact I! of relay ICH, and winding of relay ICD to During this cycle, relays PC and NC are selectively conditioned to apply the code combination to the line circuit as determined by the combination of code jumpers ll, 55 and 58. Likewise, during this cycle, the control devices at the selected station will be conditioned in accordance with the selection of relays PC and NC as determined by the positions of the control levers, such as lever ISML selectively associated with front contact I of relay W by' front contact I of relay ICD.

At the end of this cycle of operations the momentary impulse applied to conductor 35 by the dropping of contact 33 of elay SA maintains relay ISD energized over the circuit extending from conductor 35, back contact 36 of relay ISD, front contact 31 of relay ISD and lower winding of relay ISD to This circuit also extends to the right-hand terminal of the lower winding of relay ICE and since the lefthand terminal of this winding is connected to at front contact 13 of this relay, it is short circuited causing the release of the relay. When relay ISA drops its front contact 34, conductor 35 is deenergized which deenergizes the lower winding of relay ISD allowing it to drop its contacts.

The third cycle of operations is initiated because there is still another change relay picked up (relay ICH), which is eifective to select station No. I as determined by relay ICD being energized. Relay ICD is picked up over a circuit extending from back contact 86 of relay I SD, back contact 89 of relay 2SD, front contact 49 of relay 3SD, front contact 39 of relay 2CH and winding of relay 2CD to Station 2 with code call is selected as determined by the polarity of the impulses applied to the line circuit by relays PC and NC. These relays are selectively picked up as determined by the positions of code jumpers 24, 25 and 26 selected in rotation by way of front contacts 21, 28 and 29 of relay CD by the selective operation of the stepping relays. The particular controlling devices at the selected station are governed in accordance with the lever positions as selected by additional contacts of relay 2CD, such as front contact l3 which selects lever 2SML.

At the end of this cycle of operations the momentary application of potential to conductor 35 maintains relay 3SD energized over the circuit extending through back contacts 36 and 31 of relays ISD and 23D, respectively, and front contact 38 of relay 3SD to through the lower winding of this relay. This impulse is also applied to the right-hand terminal of the lower winding of relay 2CH and since this relay has potential connected to the lefthand terminal of this winding through its front contact 16, the winding is short circuited and the relay is dropped. When relay 2SA drops its front contact 34, conductor 35 is deenergized which deenergizes the lower winding of relay 3SD allowing it to drop its contacts.

It is believed that the above examples are suflicient to indicate the manner in which the stations are selected in the exact order of operation of the starting buttons. It is obvious that ifthe starting buttons ISB, 28B and 3SB are operated in the order 3, 2, 1, then relays 3CH 20H and ICH are picked up. This effects the picking up of relays 3CD, 2CD and ICD, one at a time, in rotation, as the cycles are marked off by the operation of the sequence determining relays.

In the event that button ISB is actuated three times in rapid succession, then relays lCI-I ICH and ICH will be successively picked up, being selected in rotation by contacts 10 and II of relays ISD and 28D. In this event relay ICD is picked up for all three cycles so that the station associated with this code determining relay is selected three times in rotation.

It will be apparent that the code jumpers can be connected in any desired order for obtaining the required combinations of and impulses in the control line circuit. It will also be obvious that additional code jumpers may selectively connect the PC and NC relays to the stepping relay bank selective circuit by means of additional contacts on the CD relays when the size of the system requires these additional jumpers. It will also be apparent that the present invention may be applied to a communication system of the single circuit two-wire type in which controls and indications are transmitted over the same line circuit, instead of being applied to Que system disclosed in the abovementioned prior application Ser. No. 640,062, which relates to the use of separate line circuits for the transmission of controls and indications.

Having thus described a centralized trafiic controlling system as one specific embodiment of the present invention, it is desired to be understood that this form is selected to facilitate in the disclosure of the invention rather than to limit the number of forms which it may assume,

and it is to be further understood that various modifications, adaptations and alterations may be applied to the specific form shown to meet the requirements of practice without in any manner departing from the spirit or scope of the present invention except as limited by the appended claims.

What I claim is:-

1. In combination, a circuit, a plurality of.

keys, a plurality of code determining relays corresponding to said keys, a plurality of groups of storing relays corresponding to said keys, means responsive to the consecutive actuations of said keys for consecutively operating storing relays in the groups corresponding to the actuated keys, circuit means controlled by said storing relays for selecting said code determining relays, a step-by-step device operating through a cycle in response to the operation of any code determining relay, means controlled by said step-by-step device for transmitting a distinctive code to said circuit in accordance with the particular code determining relay which is operated, means for operating said code determining relays between cycles of said stepby-step device in the order of location of the operated storing relay in the associated group, and means for selecting the particular storing relay in the group associated with the actuated key in accordancewith the sequential order in which said key is actuated.

2. In combination, a circuit, a plurality of keys, a plurality of code determining relays corresponding to said keys, a plurality of groups of storing relays corresponding to said keys, a, plurality of sequence determining relays corresponding to the number of storing relays in each group, means responsive to the consecutive actuations of said keys for consecutively operating storing relays in the groups corresponding to the actuated keys, circuit means controlled by said storing relays for selecting said code determining relays, a step-by-step device operating through a cycle in response to the operation of any code determining relay, means controlled by said step-by-step device for transmitting a distinctive code to said circuit in accordance with the particular code determining relay which is operated, means for operating said code determining relays between cycles of said step-by-step device in the order of location of the operated storing relay in the associated group, and means including said sequence determining relays for selecting the particular storing relay in the group associated with the actuated key in accordance with the sequential order in which said key is actuated.

3. In a transmitter, the combination with a code transmitting means for sequentially transmitting a plurality of series of coded impulses in the same sequential order in which a plurality of manually operable devices are operated, code each button, means for permitting energization of only one of said relays at any one time, means controlled by any one of a plurality of orders of operation of said buttons and irrespective of the time intervals between for always prcdetermining a corresponding order of operation of said relays, and means governed by each of said relays for rendering the control lever of the corresponding button effective to distinctively operate said transmitter.

5. In a code transmitter, the combination with a plurality of control levers, a starting button for each lever, arelay controlled by each button, means for permitting energization of only one of said relays at any one time, means controlled by any one of a pluralityof orders of operation of said buttons and irrespective of the time intervals between for always predetermining a corresponding order of operation of said relays, means governed by each of said relays for rendering the control lever of the corresponding button effective to distinctively operate said transmitter, and means for stor-- ing the actuations of said plurality of buttons.

6. In a code transmitter, a circuit to which codes are applied,. means for operating said transmitter through a cycle, a plurality of starting buttons, code determining means rendered active in response to an actuation of any one of said buttons for applying a distinctive code to said circuit during said cycle in accordance with the particular button actuated, means controlled by a plurality of subsequent actuations of said button before the end of said cycle for subsequently and successively applying said distinctive code to said circuit once for each of said subsequent actuations, and means controlled by the actuation of any other of said buttons following said subsequent actuations for preventing the operation of any other code determining means as long as said first code determining means remains active.

7. In a code transmitter, a circuit to which different series of coded impulses are applied, a plurality of code determining relays for controlling the application of said series of impulses to said circuit, a starting button individual to each of said code determining relays, a plurality of storing relays, a plurality of sequence determining relays, means responsive to the sequential operation of said buttons in variable order for sequentially operating said sequence determining relays in an invariable order, means responsive to the sequential operation of said buttons in variable order for sequentially operating said storing relays in corresponding variable order, means controlled by said sequence determining relays for predetermining the order of operation of said code determining relays, and means controlled by said storing relays for selecting said code determining relays.

8. In a code transmitter; a plurality of keys; a plurality of code determining relays, one for each key; means including a chain of sequence determining relays operated in response to consecutive operations of said keys for causing said code determining relays to control the transmissionof codes corresponding to the operated keys; means controlled by said keys for determining that said sequence determining relays shall always be operated in a definite rotation to determine a definite rotation in the transmission of said codes; a release circuit controlled by consecutive operations of said transmitter; and means responsive to the consecutive control of said release circuit for restoring the operated sequence determining relays in the rotation in which they were operated.

9. In a code transmitter; a plurality of code determining relays each controlling the transmission of a distinctive code; a storage relay group associated with each of said code determining relays; a plurality of keys; :1 chain of sequence determining relays for connecting said keys to said storage relays sequentially, the storage relays of the groups to which the keys are connected being responsive to the operation of the associated key for operating one of said code determining relays and operating said sequence determining relays to connect said keys to the next storage relay group in sequence; a release circuit controlled by consecutive operations of said transmitter; and means controlled by said release circuit for releasing the operated storage relays and the operated sequence determining relays in the order in which they were operated.

10. In combination; a plurality of manually operable keys; .a plurality of groups' of double wound storing relays, one group for each key; a double. wound sequence determining relay for each key; pick up circuits for said storing relays controlled by said sequence determining relays; means responsive to a first actuation of any one of said keys for picking up the first storing relay in the associated group by energizing its pick up winding; means for sticking said first storing relay by energizing its stick winding in series with a first winding of the associated sequence determining relay, said associated sequence determining relay being prevented from picking up by the actuated key energizing its second winding; means responsive to the release of the actuated key for eifecting the picking up of said sequence determining relay by deenergizing its second winding; and means controlled by the picking up of said sequence determining relay for switching the circuits of said keys to the second sequence determining relay and the second storing relay in each group.

11. In combination; a plurality of manually operable keys; a plurality of groups of double wound storing relays, one group for each key; a double wound sequence determining relay for each key; pick up circuits for said storing relays controlled by said sequence determining relays; means responsive to a first actuation of any one of said keys for picking up the first storing relay in the associated group by energizing its pick up winding; means for sticking said first storing relay by energizing its stick winding in series with a first winding of the associated sequence determining relay, said associated sequence determining relay being prevented from picking up by the actuated key energizing its second winding; means responsive to the release of the actuated key for effecting the picking up of said sequence determining relay by deenergizing its second winding; means controlled by the picking up of said sequence determining relay for switching the circuits of said keys to the second sequence determining relay and the second storing relay in each group, and means for releasing the sequence determining relays in the order of their operation.

12. In combination; a plurality of manually operable keys; a plurality of groups of double wound storing relays, one group for each key; a double wound sequence determining relay for each key; pick up circuits for said storing relays controlled by said sequence determining relays;

means responsive to a first actuation of any one of said keys for picking up the first storing relay in the associated group by energizing its pick up winding; means for sticking said first storing relay by energizing its stick winding in series with a first winding of the associated sequence determining relay, said associated sequence determining relay being prevented from picking up by the actuated key energizing its second winding; means responsive to the release of the actuated key for effecting the picking up of said sequence determining relay by deenergizing its second winding; means controlled by the picking up of said sequence determining relay for switching the circuits of said keys to the second sequence determining relay and the second storing relay in each group, means for releasing the sequence determining relays in the order of their operation; and a plurality of code determining relays individually selected and energized by the picked up storing and sequence determining relays.

13. In a code transmitter, a plurality of code determining relays, means including each of said code determining relays for controlling the transmission of a series of combinations of coded impulses, a starting button individual to each of said code determining relays, a plurality of sequence determining relays, and means including said buttons and said sequence determining relays for effecting the distinctive control of said code determining relays in any one of a plurality of distinctive sequences of operations in response to the total possible sequences of operations of said buttons independent of the time intervals elapsing between successive operations of said buttons.

14. In a code transmitter, a plurality of code determining relays, means including each of said code determining relays for controlling the transmission of a series of combinations of coded impulses, a starting button individual to each of said code determining relays, a plurality of sequence determining relays, and means including said buttons and said sequence determining relays for effecting the control of said code determining relays in any one of a plurality of distinctive sequences of operations in response to a corresponding plurality of sequences of oper ations of said buttons independent of the time interval elasping between successive operations of said buttons.

WINFRED T. POWELL.