US2081652A

US2081652A - Synchronizing and speed control system and mechanism

Info

Publication number: US2081652A
Application number: US49766A
Authority: US
Inventors: Turner Harrison Irving; Anderson Carl Ludwig
Original assignee: EAGLE SIGNAI CORP
Current assignee: EAGLE SIGNAI Corp
Priority date: 1934-12-03
Filing date: 1935-11-14
Publication date: 1937-05-25
Anticipated expiration: 1954-05-25

Description

Mayv 25, 1937.

H. l. TURNER ET Al.

SYNCHRONIZING AND SPEED CONTROL SYSTEM AND MECHANISM Original Filedv Dec. 5, 1934 O6 v OOO' |008 IOIO l/OOZ O|4 IOIZ @iene TO OTHER "om "O32 MEOH'ANlsMs AT OTHER flole H054 LOCAL 05" ,i030 CONTROLLERS MASTER TIMER u-"Tees@ MECHANlsMs AT A LOCAL CONTROLLER SYNCHRO- 320- 3.@ ggg TRL im 42 29o 48o- @CAM 3|'Z/ 30 MT' 306 I 2% 30o 50e' Qca Qaoe ROT TMT 3041 I A Es O 204 VARY sPEE I l l l l L .1 zo 4,22 @24 ce2@ @ze @so L zaabzf. LOCAL 650 g CONTROLLER L ,i @edl OQO; Ien/,91H Q52] SPEQIAL SU PLY FOFl MOTQRIMI VQ;- E lI G4- @e4 36%/ UNEF-gg 'N8 670 1 -Q70 INVENTORS HARRlSON l. TURNER l 'Ezl F668, I CARL L. ANDERSON IL Il-67o BY 766m/ ATTORNEY Patented May 25, 1937l accises SYNCHRONIZHNG AND SPEED CGNFRL SYSTEM AND MECHNESIi/ Harrison iirving Turner and Cari son, Moline, Ill., poration, chusetts Original Ludwig Anderassignors to Eagle Signat Cor- Moline, Ill.,

a corporation of Massaapplication December 3,1934, seriai No. 755,742. Divided and this application November 14, 1935, Serial No. 49,76@

'i Ciairnsu This .invention relates to synchronizing and speed control systems and mechanisms, and more particularly to such systems and mechanisms as those utilized ,for governing the operation of a plurality of electric highway trafc signal controllers in situations where it is desirable to maintain preselected speeds and coordination oi operation between such controllers while permitting variations of durations and/or character- I) istics of components entering into cycles of changes of signal aspects irrespective of the character of electric current utilized.

Such synchronizing and speed control systems and mechanisms heretofore available for governi ing the operation of highway traiiic controllers have embodied characteristics which precluded variations of cycle durations as well as accurate synchronism therebetween and, to attain most perfect results, have necessitated utilization of electric current of special character.

Furthermore, the complex and intricate character of synchronizing and speed control systems and mechanisms which have heretofore been supplied for such service has resulted inthe dei sign and utilization of mechanism subject to disarrangementA and, when disarranged, requiring highly skilled services for effecting repair and readjustment.

It is therefore an important object of this in-l vention to provide such systems and mechanisms for associating a local highway trac signal controller with a master timer, which systems and mechanisms are capable of periodically and automatically effecting and maintaining synchronical relationship between said local controller and said master timer by synchronizing the operation and correcting the operating speed of said local controller.

Another important object of this invention is to provide such systems and mechanisms which are capable of periodically and automatically effecting needed revisions in the operating speed of said local controller, whereby to maintain substantially synchronical speed between the operation of said local controller and that of said master timer.

Another object of this invention is tov provide such systems and mechanisms for association with a local highway trafc signal controller as will be capable of periodically and automatically effecting revisions in the speed of operation of such local controller necessary tovcompensate for any change in speed therein such as may rel sult from atmospheric temperature variations or otherwise. fg

(CHL. .w25-293) Another. important object oi this'invention is to provide such systems and mechanisms in association with local highway trahie signai con.- trollers at a plurality of traiiic lane intersections whereby to govern the operating speeds of the respective controller in such relationship to a master timer as to cause displays signal aspects at respective lane intersections facilitating progressive movement of trails. l

Another important object of this invention is to provide such systems and mechanisms for aslsociation with local highway trailc signal controllers at a plurality of traffic lane intersections whereby to establish, periodically and automatically, concurrent attainment of predetermined synchronizing stages of respective controllers and thereafter act to maintain predetermined relationships between ensuing operative stages of respective controllers through automatic accomplishment of needed operating speed revisions at each local controller.,

Another vinmortant object of this invention is to provide such systems and mechanisms which, irrespective of the character of the electric current employedV for actuation thereof, may be utilized for establishing the times of occurrence of a predetermined operative stage and for maintaining predetermined relatlonships between such stage and other operative stagesa A further important object of this invention is to provide such improved systems and mechanisms which, for the accomplishment or all, any one or any group of the foregoing objects shall be of greater effectiveness and reliability, composed of a smaller number of parts severally characterized by strength', durability and'facility of assemblage, as well as amenable to a lower cost of manufacture.

Other and more specific objects and' advantages will appear in the following description of an illustrative embodiment of this invention, or will be apparent to those skilled in this art.

A traic signal system including a local highway traiic signal controller of a type with which this invention may be employed is fully shown and described in the zzo-pending application oi Harrison Irving Turner and Carl Ludwig Anderson, the present applicants, tiled December 3rd, 1934, Serial No. 755,742, for Signal Controlling and duration varying systems and mechanisms therefor, in which application this invention was originally disclosed and of which application this is a divison. A

Detailed description of the circuits and mechanism of such traffic signal system will-therefore be herein omitted.

In a preferred embodiment of this invention, the foregoing objects and others ancillary thereto are preferably accomplished as follows:

A master timer comprises mechanism for electrically energizing and deenergizing two channels which are associated with one or more local highway trafilc signal controllers; such eneagizations and deenergizations of channels occurring independentlyl at regular predetermined intervals and continuing for regular predetermined durations.

Such highway trafllc signal controllers may be of any desired type which is governed by a variable speed motor. In accordance with this invention, speed regulating means is associated with the motor of each such controller, which regulating means preferably comprises electrically operable actuating means, a speed revision determining cam, and contacts for actuation by the respective cams.

Said actuating means preferably comprises two motors applied for actuating mechanism associated with the controller motor so that respective ones of said driving means motors may be energized for effecting increase or decrease of the operating speed of its associated controller motor.

Should the speed of the controller governing motor be such as to cause attainment of a predetermined stage in the operatio'nfof the speed revision determining cam substantially in advance of a time preestablished therefor by the master timer, one of the master timer channels will be energized whereby one of the speed regulating motors will be energized to effect mechanism alterations such as will retard the operating speed of the controller governing motor.

Should the controller governing motor so operate as to cause attainment of another predeterv mined stage inthe operation of the speed revision determining cam at a time substantially later than that preestablished therefor by the master timer, said one of the master timer channels will be energized whereby the other of the speed regulating motors will be energized to effect mechanism alterations such as will increase or accelerate the operating speed of the controller governing motor.

Should said controller governing motor so operate as to cause attainment of still another predetermined stage in the operation of the speed revision determining cam at a time substantial-- ly co-extensive with the time during which said one of the master timer channels is energized, neither of the speed regulating motors will be energized and operation of the controller governing motor will continue without alteration of the speed thereof.

A synchronizing cam is associated with the remaining master timer channel and, upon attaining a predetermined stage, interrupts the normal current supply path to the controller governing motor whereupon should said motor be out of synchronism by a substantial amount it will be brought to rest and will be ,restarted only upon deenergization of said remaining master timer channel. Such deenergization will result in effective establishment of a special current supply path for said motor.

Should the synchronizing cam attain the foregoing predetermined stageA substantially simultaneously with or immediately following the deenergization of the said remaining master timer 4 bodiment, though practical, is by no means the only one which the invention may assume, wherefore the invention is not confined to any strict conformity with the more or less diagrammatic representation of the drawing but may be changed and modified in various particulars so long as such changes and modifications make no material departures from the invention, as more particularly set forth in the annexedlaims.

In the accompanying drawing, reference characters employed in the aforementioned application of which this is a division have been largely so employed as to facilitate comparison therewith, and like parts are designated by the same reference characters throughout the several views in which Figure 1 is a schematic "across-the-line" representation of circuit connections combined with a diagrammatic presentation of mechanisms and an arrangement of parts embodying this invention; and

Fig. 2 is a composite chart representative of various operating and circuit characteristics of an embodiment of this invention in comparison with those of a master timer.

In Fig. 1 of the drawing, mechanism and circuits indicated below a dash line h are for association with a local traillc signal controller. Such circuits and mechanism comprise a shaft 204 rotatable for establishing signal cycle durations and times of occurrence thereof for the associated local controller such as will be in predetermined relationship to cycles of other like controllers.

The shaft 204 is driven by means of an electric motor which may be of a type operable by direct current or of a type operable by alternating current. For convenience, such motor is indicated in the drawing as an alternating current` induction type motor Mi comprising an electromagnet 290, a disc 292, a shaft 294, a worm gear 296 and a worm wheel 298; said wheel 298 being secured to shaft 204 for effecting rotation thereof together with a gear 300 also fixed upon said shaft.

A gear 300', driven by the gear 300, is secured to a shaft 304 and acts therethrough to drive two cams which will be herein respectively referred to as the synchronizing cam 306 and the "speed control cam 308.

Contacts 400, 482 and 484 are associated with ,cam 306 and

contacts

490, 492 and 494 are associated with the cam 308.

Cam 306 comprises a cut-away portion 306 while cam 308 comprises a full raised portion 308, a semi-raised portion 30B' and a depressed end of said contact 400, for holding same in engagement with said contact 482, except when the cut-away portion- 306 of said cam is situated in the path of the end of said contact 480, at which time its bias will cause it to move into engagement with contact 4 04 and away from contact 462. l

The contact 490 associated with the cam 306 is situated between the contacts |92 and 094 and is biased for movement away from the former and into engagement with the'latter; said 4vcontacts 492 and i3d being so positioned with relation to said contact 490 that, in the course of the movement thereof, said contact 5130 will break with one before making with the other.

The cam 300 is situated in the path of the free end of said contact 490 for holding same in engagement with said contact 002 when the full raised portion 303 of said cam is situated in the path of the end of said contact 090; for holding said contact 030, against the urge of'its bias, in an intermediate or non-contacting position when the semi-raised portion 303' of said cam is situated in the path of said end; and for permitting said contact -to move, responsive to the urge of its bias, into engagement with contact 431i and away from contact @.32 when the depressed or cut-away portion 3053" of said cam is situated in the path of said contact.

lt is preferable that the

gears

300, 300 shall.

be of such character that simultaneous and synchronical movement will be imparted to the

shafts

204 and 304 and the parts carried there-y by to the end that a cycle of the local controller, as determined by the rotation of the `shaft 204, will coincide in all respects with a cycle of the

cams

306 and 308 carried by the shaft 304.

The motor MI has a shading coil 290 rotatable with a shaft 3|0 foreiecting revisions of the tordue applied to'the disc 292, in a well known manner.

Should motor Ml be of a direct current type, as hereinbefore suggested, the shaft 3|0 in rotating may serve to revise the torque of the motor Y MI by effecting'revisions in circuit resistance in any well known manner.

A disc 322 drives the shaft 3|0 through beveled gears 3|4 and 3|0 and is so associated with the electromagnets M2 and M3 that the excitation of one of said electromagnets will cause said disc to rotate said shaft in one direction and the excitation of the other of said electromagne'ts will cause rotation of said shaft in opposite direction. For convenience in description, the electromagnet M2 and the portion of the disc 322 associated therewith will be herein referred to as motor M2 and the electromagnet M3 and its associated portion of the disc 322 will be herein referred to as. motor M3.

From the foregoing it will be evident that energization of motor M2 will cause rotation of the coil 290 in one direction, and energization of the motor M3 will .cause rotation of said coil in the opposite direction.

The permanent magnet 3|8-is associated with disc 292, in a manner well understood by those skilled in the art, to serveas a magnetic brake and thereby maintain a comparatively slow and uniform speed of rotation of the disc 292 and to 'further serve to 'minimize coasting by hastening deceleration when driving current has been cut off. It will be obvious that direct current motor mechanism may be utilized in place of the a1- effect closed circuit conditioning upon deenergization of relay llt. Relay H6 has a front contact litt which is engaged by a movable contact |64 upon energization of said relay liti.

The master timer or controller T indicated in the upper portion oi Fig. 1 of the drawing above the dash line h comprises a motor M6, of alternating or direct current type, for driving a gear 600 which, in turn, drives a gear 602 .sci cured to a shaft d. Cams 006 and 608 are also fixed on said shaft 604. and have cut-away portions and 603 and .raised portions 606" and 000", respectively.

A tracer contact 030 is so associated with the cam 006 and with a contact titi that, when rotation of said cam carries its. raised portion 6.06 into the path of said tracer conta-ct, said contact 660 is moved into engagement with said contact SH2; and, when said raised portion 006" r is withdrawn and said cut-away portion 606 is presented, said Contact 6|0 is moved out of engagement with said contact 6|2.

A tracer contact 6M is so associated with the cam 60Btand with a contact BIS that, during presentation of the raised portion 608 of said cam, said tracer contact is separated from said contact BIB; and, when said raised portion 608" is withdrawn and said cut-away portion 608 is presented, said tracer contact isznoved to engage said contact 6|6.

Circuit connections The electrical connections provided between the mechanisms described are as follows:

Conductors |000 and |002 are for conducting energy from a suitable source of electric current supply to the master timer T.

A third bus conductor |030'is connected to source conductor |000; a fourth bus conductor |036 is connected vto source conductor |002 through a normally' closed switch |002; the four bus conductors |030, |032, .|034 and |036 thence extending from the master timer T to and for parallel connection with the synchronizing and speed control systems and mechanisms of each of one or more local controllers. Such connection to be hereinafter described in connection withthe exemplication of such a system and'mechanism associated with the single local controller indicated in Fig. 1.

A further connection at the master timer includes the switch 6|8 which, when closed, conin Fig. 1 ielown the dash line h) comprise the conductors 002 and'022 for conducting energy from a suitable" source of supply to such local controller. Such current supply may be either the same as that to which the conductors |000 and |002 of the master timer are connected, or one which is independent thereof.

Conductor 030 connects one end of Athe wind-` ing of relay 400 with master timer bus conductor |032, conductor 040 connects one end of the winding of relay 462 with master timer bus conductor |034, conductor 030 connects the remaining ends o! the'windings of relays 400 and 402 with the master timer bus conductor |000, a conductor 000 connects conductor 036 (and therefore bus |030) with one end of the winding of relay I|6, and a conductor 030 connects the remaining end of such winding to the master timer bus |030.

At each local controller to be synchronized and speed controlled by master timer T, connections corresponding toconductors 030, 040, 036 and 030.L should be made. t

Conductor 042 connects source conductor 002 with one terminal of each of the motors Ml, M2 and M3; the remaining terminals of which motors are respectively connected by conductors 000, 046 and 040 with contacts 400, 402 and 404.

Conductor 042 connects contact 400 of relay 402 with contact 400 of cam 300; conductor 044 connects contact 414 of relay 400 with contact 404 of cam 000; and conductors 006 and 102 connect contact 412 of relay 400 with contact 402 of cam 306. y o

A branch of conductor 192 leads to the movable contact |04 of relay ||0, and a conductor 000 connects the stationary contact |04 of relay ||6 with source conductor 022.

Conductor 020 connects the respective movable contacts 404 and 410 of relays 402 and 460 with source conductor 022.

Operation as follows:

mm source conductor un, through concluetor |004, motor M0, conductor |006, switch |000,

adjustable resistance |0|0 to current source 4conductor mz.

Prom source conductor |000 through rely 460 by way of conductors |030, 036, relay 400, conductors 030.1032 and |0|4, contacts 0|0 and 0|2 and conductor |0|2 to source conductor 4provided for causing energization of the motor MI. Such path leads from conductor 002 through conductor 042, winding of motor MI, conductor 050, contacts 400 and 4,02, conductor 192, contacts I 04, |04 and conductor 000 to source conductor 022. ,i

'I'he energization "of motor MI effects rotation of the shaft 294 together with the cams 300 and 006. Such rotation causes the cut-away portion 306 of the cam 306 to be presented to the tracer contact 400, whereupon the previously effective current supply path for the motor Ml is interrupted at contacts 400, 402; the contacts 400, 404 having just previously closed in preparation for the establishment of another current path for subsequent restarting and/or continued operation of said motor.

If, at the time of the interruption ofsuch previously effective current supply path of the motor MI, the cams' moving with the shaft 304 are somewhat in'advance of :synchronism of the mas- From source conductor |000 through relay ||6 by why of conductors |030, 000, 000, relay H0,

. conductors 030, |030 and source conductor |002 adjustment of the resistance- |0|0; the relay I I0 ter timer T, energization of relay 460 will cause its movable contact 410 to be separated from its stationary'contacts 412, 414, and no other energizing current path for motor MI will be immediately available.- The motor MI will therefore be brought to and maintained atrest until such time as another energizing current path is rendered available through deenergization of relay'400. This stage in the operation of the mechanism is sometimes referred to as the re-synchronizing period.

Assuming that the master timer T and the shaft 304

and'cams

300, 300 are in synchronism at the re-synchronizing period, as would ordinarily be the case, the cam 006 of the master timer T fwill. as there-synchronizing period is about to become effective, withdraw its raised portion 606" and present its cut-away portion 000' to the tracer contact 6|0, thus permitting this contact to separate from the contact 0|2, and thereby break the previously effective current path for energization of the relay 460.

Following such deenergization of said relay, its contact 410 moves -into engagement with the contacts 412, 414. 'Iwo paths are thus made available for supplying energizing current to motor MI. Both of these paths lead from the source conductor 002 through conductor 042. motor MI, conductor 000, contacts 400, 404, conductor 044, contact 414 to movable contact 410 where the two paths branch, one leading through the movable contact 410 and conductor 020 to source movable contact 410 to lcontact 412, thence through conductors 000, 102, contacts |64, |04

and conductor 000 to source conductor 022.

'Ihe purpose of these two paths in parallel will be hereinafter more fully explained in connection with the description'of the operation of the mechanism without the supervision oi'. a master timer.

When the motor MI thusresumes rotation of the

shafts

204, 304 and of the cams 300, 300l the cut-away portion 306 willbe withdrawn and the raised portion of the cam 000 will be presented for engagement with the tracer contact 400; which contact 400 will therefore move into engagement with the contact 482 andthereby close the originally described-energizing current path for motor MI, which path will thereafter remain closed until ythe cut-away portion 306' of cam 306 is again presented to the tracer contact 480, at the next re-synchronizing period; contact 480 being moved away from contact 484 after it has engaged contact 482.

It will be observed that the contour of the cam 606 is such as to maintain the contacts 6|0, 6|2 in closed relationship throughout approximately three-quarters of each revolution of the shaft 604, upon which said cam is xed; and that the contour of the cam 608 is. such as to permit closure of the contacts 6|4, 6H;y during approximately 6% of its rotation, incidental to the latter portion of theclosure of the contacts 6|0, 6I2.

During the closure of the contacts 6I0, 6|2, just referred to, a current path is effective from source conductor i000, through conductors |030, 836, relay 468, conductors 838, I|4, contacts 6I0, 6|2

and conductor i0|2 to source conductor i002, for

energizing relay 468.

Similarly, during closure of the contacts 6| 4, 616, a current path is effective from source conductor i000, through conductors |030, 836, relay 662, conductors 840, i034, l0l6, contacts 6l6, 6l4

and conductor 0l2 to source conductor |002 for energizing relay 462.

The relative times of occurrence and durations of energizations and deenergizations of the

relays

662 and 468, as well as the consequences thereof 'under `various conditions, are graphically represented in the charts of Fig. 2.

Between horizontal dashed lines 650 and 652, in the upper portion of the chart of Fig. 2, are

lines

660, 660 and 662 representative of the significant results of the operation of .the master timer T in establishing times of occurrence and durations of re-synchronizing and speed regulating periods; between horizontal dashed lines 652 and 654, the

lines

664, 666, 668, 610 are representative of the signicant results of the operation of a local' controller in synchronism with the master timer T, in terms of the conditioning thereof for response to the current path revisions incidental to the operation of said timer; between horizontal dashed lines 654 and 65,6 the lines 664', 666', 668' and 610' correspondingly indicate results effective in a local controller operating at a speed slower than that which would maintain an intended relationship thereof with the master timer; and between horizontal dashed unes 65s and 65s the unes ssa", stuw/,tsarl and 610" correspondingly indicate resul' /eiective in a local controller operating at a//Mpeed faster than that which would maintain an intended relationship thereof with the master timer.

The space between the dashed vertical lines 620 and 620' is representative of the time of one revolution of the shaft 604 together with the cams 606 and-608 moving therewith, and hence of the intended time for a cycle of signal presentations. The Vertical dashed

lines

622, 624

626, 628, 630, 632 and 634 are .spaced from the line 620 at distances respectively representative of approximately 4%, 25%, 50%, '75%, 90%, 92% and 98% of the duration of a, signal presentation cycle. l

Returning now to a considerationr of the signicant resultsof the operation of the master timer T, and associating such results with the representatlonsthereof in Fig. 2,-the line 660', extending from vertical line 620 to the vertical line k624, is representative of the time of occurrence within the cycle, and the duration, of the separation of the contacts 640, 6I2 due to withdrawal of the raised portion of the cam 606, together with the consequent deenergization of the relay 468, the contact 410 of which therefore moves into engagement with its contacts 412 and 414. For want of a better term, the phrase Special Supply for Motor MI has been applied to this line on the drawing.

The portion of the cycle during which the contact 410 is out of engagement with the contacts 412, 414 is indicated by the line 660. The line .662, extending from vertical line 632 to vertical line 634, is representative of the time of occurrence within the cycle, and the duration, of the closure of the contacts 464, 466 of the relay 462, resultant from withdrawal of the raised portion-of the cam 608 from the contact 6|4, which thereupon engages the contact 6l6.

The line 666,"extending from vertical line 622 to vertical line 620', is representative of the portion of the time occupied by one cycle of the operation of the master timer T, during which portion a local controller operating in synchronism with said timer will have its contact 480 held in connection with its contact 482 by the raised portion of its cam 306; the line 664, ex-

tending from vertical line 620 to vertical line 622, is representative of the portion of such cycle during which the contact 480 is permitted (by withdrawal of the raised portion of the cam 306) to engage the contact 484.

The line 668, which also extends from vertical line 620 to the vertical line 622, is representative of the portion of said cycle during vwhich the full raised portion 308" of the cam 308 causes the contact 490 to engage the contact 492; and

the line 610 is representative of the portion of said cycle during which said contact 490 is permitted to engage the contact 494, through presentation of the'depressedportion 308" of said caml 308 thereto. In the portion of such cycle represented by the space between the vertical lines 630 and 620', the contact 490 is supported by the semi-raised surface 308' in such a position that it does not engage either contact 492 or 494, and for this reason neither line 668 nor line 610 extends through this space.

Lines 664', 666', 668 and 610' are representative of

lines

664, 666, 668 and 610, respectively, for a local controller which is operating at a speed insuicient to maintain it in synchronism with the master timer;.and the lines 664", 666', 668" and 610" are correspondingly representative for-a local controller which is operating at a speed exceeding that which would maintain it in synchronism with the master timer.

Results of relay and contact positionings just described, in View of the current paths established therebetween as hereinbefore more fully explained, may be summarized as follows:

A local controller operating in synchronism with the master timer will maintain continuous operation of its motor MI, and-its motors M2 and M3 will not be energized. The continuous operation of the motor MI will be effected for the reason that (as represented by the synchronous inception of the lines 660' and 664 in.

Fig. 2) upon each occurrence of the resynchronizing period, the current path through the convtact 484 will be completed because the relay 468 is deenergized wheneventhe cut-away portion 306 of the cam 306 is presented to its contact 480, and said contact 480 has thereupon moved into engagement with said contact 484 and away nom the positioning of the contact m (by the.

from the contact' 2. Furthermore. the nonenergisation of the motors M2 and MI will result sani-raised portion Ill'nf the cam 3l!) out oi' engagement with the contacts 492 and l, throughout the time when relay 2 is energized by closure of the master timer contacts III, lli, resultant from presentation of the cut-away portion lll of its associated cam tu. Such cyclic relationship is indicated by the absence of lines l and |10 in the portion of the cycle occupied by the line 2, and by recurrence of the hnes l and l in relationship 'to vertical line 82|' identical with that of such lines to the vertical line 82|.

A local controller operating at a speed somewhat less (say not more than 20% slower) than that necessary for keeping it in synchronism with the master timer T, will maintain continuous Operation of its motor Mi and its motor M2 will not be energized However, its motor Ml.

will be energid'during a portion of the cycle vfor the purpose of revising the adjustment of the shaft III, and parts controlled thereby, in orderthatthespeedoithe motorMi maybe moderated 'nie continuous operation of the motor Ml will be veffected for the reason that. whenever the out-away portion III' of its associated cam 3 is presented to its contact I, and said contact l has thereupon moved into engagement with the contact l and away from the contact 2, the current path through the contact l will be completed because the relay I is at such timedeenergiseddue to the contacts III, .I2 of the master timer being separated by withdrawal o( the raised portion of the cam ill.

This is represented by the left-hand one of the linesill' which, starting at vertical line 02! simultaneously with the left-hand one of the lines nl', falls entirely within the portion of the cycle occupied by the latter line; and the recurrence or right-hand one of the lines 4' ,starts to the right of the vertical line 02|'. and, although not having its inception simultaneously with that of the associated one of the lines ttl', nevertheless falls entirely within that portion of thecycle whichis represented by saidline lil.

The non-energisation of the `motor M2 results from positioning of the contact "I away from the contact 2, throughout the energimtion of the relay 2 caused by closure of master timer contacts lll, lll, because the full raised portion ill" of the cam l does not at that time engage said, contact 0. Inasmuch, however, as the time from the start of the cycle for the cam tu to carry-m semi-madman ill' into engagement with the contact. l (as represend by line 810') exceeds the intended time (as represented by line 01|) to the extent by which said line 81B' projects to the right of the vertical line the contact t is permitted to remain in connection with the contact l during a portion of the closure of the contacts l, l of relay 2, (which portion is represented by the amount by which ell extends to the'right cf line O82 and is therefore concurrent A -with a part of the line 2) throughout which portion the motor Mttwill act through the shaft III, the gears llt, III to so rotate the shaft.V `Il as to cause acceleration of themotor MI.

'111e' mcelerating action of motor Mi will be v repeated, as lust described. at the corresponding the cycle of the local controller mechanism operated thereby to catch up with its intended relationship with the cycle of the master timer. It is evident that. in bringing about this result. the speed of the motor Ml will have been so increased that, once the cycle of the local controller has overtaken its intended relationship to the master timer, the speed of the motor MI will exceed that which would maintain such relationship. Action will therefore ensue, in a manner which will hereinafter be more fully explained. for suitably decreasing the speed of said motor MI.

The current path for energizing the motor M3. I

as just referred to, is as follows:

From source conductor 852 through conductor 842, motor M3, conductor l,

contacts

494, 490, conductor 942, contacts 466, III and conductor .2l to source conductor 822.

A local controller, operating at a speed greater than that necessary for keeping it in synchronism with the master timer T, will have the operation of its motor Mi suspended during a portion of each cycle, and its motor M3 will not be energized. However, its motor M2 will be energized during a. portion of the cycle for the purpose of revising the adjustment of the shaft 3l. and the parts controlled thereby, in order that the speed of the motor MI may be retarded.

The suspension of the operation of the motor Mi will occur when the cut-away portion 306' of its associated cam 306 is presented to its contact "l, and such contact has thereupon moved into engagement with the contact l and away from the contact 482; because the current path through the contact l will en be interrupted at the relay 8, energization of which will be sustained due to the contacts Bil, N2 of the master timer T remaining closed pending withdrawal of the raised portion of the cam t.

Upon deenergization of the relay 48|, energization of the motor Mi will be resumed, so that it will drive the mechanism operable thereby until a corresponding stage is attained in the next succeeding cycle. This is represented in Fig.4 2 by line BM", which is shown as starting at a point in the cycle corresponding with the termination of the line B66 and extending to the vertical line 622'.v

- The portion of the line 86E" between its inceprelay 4t2, as represented by the line 662.

The energization of the motor M2 results from the closure of the contacts 490. 492 during a portion of the energization of the relay 2, as indicated inlligi 2 by the distance which the line "l" extends to the left of the vertical line IN. Throughout such energization, said motor M2 will so rotate the shaft SIU as to cause retardation of the motor Ml. Such retardation will thereafter be repeated in the corresponding stage of each succeeding cycle until the speed of the motor Ml has been so decreased that the stage of the cycle of the local controller assumes its intended relationship to the cycle of the master afoise i 7 timer. It is evident that, in bringing about this result, the speed of the motor M| will have been so decreased that, once the cycl/ of the local controller has thus attained irrt/ended relationship with the master timer/the speed of said motor M| will be insufficient to maintain such relationship. Action r,will therefore ensue in a manner hereinbefore' more fully described for suitably increasing the speed of motor MI.

The current path for energizing the motor M2 as just referred to is as follows:

From source conductor 852 through conductor 842, motor M2, conductor 946,

contacts

492, 490, conductor 942, contacts 466; 464 and conductor 820 to source conductor 822.

Under ordinary operating conditions, the regulating actions which have just been described are not of extensive amplitude. If, however, a local controller has, by any means, gotten greatly out of step with the master timer, so that extensive rotation of the shaft 3|0 occurs before an approximation of synchronism is attained, a

so-called hunting actionvof the speed control` ling mechanism of progressively decreasing amplitude will continue until an adjustment of the shaft 3|0 has been attained which will cause operation of the motor MI at a speed such that the cycle of the local controller will substantially coincide With that of the master timer.

if it is desired to lengthen or shorten the cycle time of the associated controllers, this may be done by varying the resistance |0||l at the master timer whereupon the speed of the motor M6 will be correspondingly altered, with resultant revision of the positionings of the speed regulating shading coils 290 of the motor MI of all local controllers, in a manner hereinbefore more fully explained.

Should it be desired that the operation of the local controller be suspended, switch 6| 8 Should be moved to closed position, thus effecting continuous energization of relay 468 to cut off the normal current supplyto motor MI. Furthermore, switch |002" should be opened to permit deencrgizati on of relay I6, thus opening the path through contacts |64, |04 to motor MI.

In practical use, it has been found desirable that all current paths for the signal lights, motors, relays, etc., which lead from each local controller to source conductor 822 shall pass through its associated contacts |64, |04. Such practice enables the deenergization of relay I6 during energization of relay 468'to effect complete suspension of all/activities of the associated local controller'and its synchronizing and speed control system and mechanism, and to extinguish the signal lights.

The foregoing descriptions have been, for the most part, based upon the assumption that mechanism such as that shown below the dashed line h in Fig. l is to be utilized irl-conjunction with a master timer such as that shown above the dashed line h in Fig. l; however, controllers supervised or governed in accordance With this invention may be placed in service Without providing any connection therefrom with a master timer, as when installed at an isolated intersection or location so remotely situated with reference to other intersections or points needing trafc control as to in no way require master timer supervision.

Controllers supervised or governed in accordance with this invention, as hereinbefore more fully described, will maintain efficient operation even in the event of discontinuance of a previously effective resynchronizing or other connection with a master timer. Thus, should the benefits of a master timer be dispensed with or should power failure or circuit trouble interrupt the supervision of the local controller mechanism, such mechanism would continue operating at the speed last determined by the positioning of the shading coil 290'; motor Ml being continuously energized, irrespective of the positioning of contact 480, because of continuous deenergization of relay 468 and resultant engagement of its movable contact 410 with the stationary contacts 412 and 414. In such an event, if all of the current paths for the signal lamps, motors and relays of the local controller4 pass through contacts |64, |04, (as hereinbefore indicated as desirable) current flow for such motors, lamps and relays from source conductor 822 will pass uninterruptedly from such conductor 822 through conductor 820 contacts 410 and 412, conductors 896 and.'|92 to contact |64 at which point the path branches to lead through the various motors, lamps, relays and controlling circuits to the source conductor 852.

It will be evident from the foregoing that this i.

invention might have been illustrated in the accompanyingdrawing as embodied in any one of many different kinds of mechanism. That which has been selected for use as illustrative of the invention has been chosen as a matter of coni; venience, and not because it exhausts the scope of theinvention in its application to the various uses for which it is suited. Furthermore, it should be remembered that various features of this invention may be advantageously utilized singly or in I.

groups containing less than all of said features.

The explanations hereinbefore given as to illustrative applications of this invention to certain of the many possible uses thereof, when considered in connection with the accompanying drawing, are believed to be fully sufficient to enable those skilled in this art to readily apply this invention to all situations to which it is suited.

Claim is made to, and it is desired to secure by Letters Patent of the United States of America, all generic and specific features of the invention shown by the accompanying drawing and as hereinbefore more fully described,.including all features which may, as a matter oflanguage, bc said to fall between the scope of any of the folf.'

lowing claims.

We claim:

l. In a synchronizing and speed control system, means for periodically formulating impulses in respective ones of two channels, controlled mech- V:

anism having a predetermined cycleof operation and including a variable speed driving motor, means associated with one of said channels and rendered effective during each cycle of said mechanism for synchronizing said mechanism responsive to impulses of said Lormulating means in said one of said channels, means associated with and renderedresponsive to impulses in the other of said channels at predetermined stages in each means for periodically formulating impulses in respective ones of two channels, controlled mechanism having a predetermined cycle of operation and including a variable speed driving motor, means associated with one of said channels and effective during each cycle of said mechanism for synchronizing said mechanism responsive to impulses of said formulating means in said one of said channels, means associated with and responsive to impulses in the other oi' said channels for increasing or decreasing the speed of the driving motor resultant from premature or tardy time of attainment of predetermined stages in the operating cycle of said mechanism with respect to the time of occurrence of impulses in said other channel whereby the speed of said motor will be governed for substantially maintaining predetermined relationship between formulation of impulses and cycles of controlled mechanism operation.

3. In a synchronizing and speed control system, means for periodically formulating impulses, controlled mechanism having apredetermined cycle oi operation and including a variable speed driving motor, means eilective during each cycle of said mechanism for stopping csaid variable speed driving motor, means responsive to said impulses for rendering said stopping means in-l effective when said driving motor is substan-` tially in step with said periodic impulses, means responsive to said impulses for increasing or de-l creasing the speed of said driving motor resultant from premature or tardy time of attainment of .predetermined stages in the operating cycle of said mechanism with respect to the time of occurrence of said impulses whereby the speed of said motor will be governed for 'substantially Vmaintaining predetermined relationship between Iformulation of impulses and cycles of controlled mechanism operation.

4. In a synchronizing and speed control system, means for periodically formulating impulses in respective ones of two channels, controlled mechanism including a variable speed driving motor, means associated with one of said channels and rendered effective incidental to operation of said mechanism for synchronizing said mechanism responsive to impulses of said formulating means in said one of said channels, means associated vwith and rendered responsive to impulses in the other of said 'channels at predetermined stages in the operation of said mechanism for increasing or decreasing the speed of said driving motor resultant from premature or tardy time of attainment of such stages with respect to the time of occurrence of impulses in said other channel whereby the speed of said motor will be governed for substantially maintaining predetermined relationship between formulation of impulses and attainment of such stages of controlled mechanism operation.

5. In a synchronizing and speed control system, a master timer comprising a constant speed driving motor, a shaft driven byV said motor, camssecured to said shaft, contacts associated with said cams and periodically actuated thereby, a resynchronizing channel periodically energized and deenergized responsive to contacts associated with one of said cams, and a speed control channel periodically energized and deenergized responsive to contacts associated with another one of said cams; a controlled mechanism comprising variable speed motor, a shaft driven by said mechanism motor, cams secured tosaid mechanism shaft, contactsassociated with said mechanism cams and periodically actuated thereby, means associating said re-synchronizing channel with the Icontacts associated with one of said mechanism cams for rendering said lre-synchronizing channel effective to synchronize said mechanism during a concurrent predetermined conditioning of said re-synchronizing channel and of the contacts associated with said one of said mechanism cams, means associating said speed control channel with the contacts associated with another of said mechanism cams for rendering said speed control channel eifectively associated for causing alteration of theJ speed of said variable speed motor during a concurrent predetermined conditioning of said speed control channel and of the contacts associated with said other one of said mechanism cams and means responsivey "to said effective association therewith of said speed control channel for altering the speed of said variable speed motor.

6. In a synchronizing and speed control system, f' means for periodicallyformulating impulses, a

controlled mechanism having a cycle of operation oi predetermined length and including a variable speed driving motor, means eifective during each cycle of said mechanism for synchronizing the cycles of said mechanism responsive to said formulating-means impulses, means mechanically connected with said driving motor and responsive to said impulses for exerting a force to cause increase or decreasel in the speed of said driving motor resultant from premature or tardy time of attainment of predetermined stages in the operating cycle oi said mechanism-with respect to the time of occurrence of said impulses whereby the speed of said motor will be governed for substantially maintaining predetermined relationship between formulation of impulses in the cycles of controlled mechanism operation.

7. In a synchronizing and speed control system, the combination of periodic impulse formulating means, means for controlling the speed of the periodic impulses, controlled means including a driving. motor having a shading coil movable for eilecting adjustments in the speed thereof, a second motor for moving said shading coil in one direction or the other, means jointly responsive to impulses of said formulating means and to said controlled means for causing said second motor to move said shading coil in one direction or the other, and means responsive to lack of synchronization between the impulse formulating means and the controlled means for deenergizing the shading coil.

HARRISON IRVING TURNER. CARL LUDWIG ANDERSON.