US2609434A - Traffic signal controller - Google Patents

Traffic signal controller Download PDF

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US2609434A
US2609434A US26814A US2681448A US2609434A US 2609434 A US2609434 A US 2609434A US 26814 A US26814 A US 26814A US 2681448 A US2681448 A US 2681448A US 2609434 A US2609434 A US 2609434A
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switch
dial
solenoid
shaft
circuit
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US26814A
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Diebold Anton
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Marbelite Co Inc
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Marbelite Co Inc
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    • GPHYSICS
    • G08SIGNALLING
    • G08GTRAFFIC CONTROL SYSTEMS
    • G08G1/00Traffic control systems for road vehicles
    • G08G1/07Controlling traffic signals
    • G08G1/085Controlling traffic signals using a free-running cyclic timer

Definitions

  • DIEBOLD TRAFFIC SIGNAL CONTROLLER Sheets-Sheet 1 Filed May 15, 1948 J/yna/ Aufo Run 6'? Off lkmd Resyn VINVENTOR. 4/710/7 0 /'6 60/0 ATTORNEYS Sept. 2, 1952 A. DIEBOLD TRAFFIC SIGNAL CONTROLLER Filed May 13, 1948 fin/an INVENTOR. i i
  • the present invention relates to improvements in traffic signal controllers and relates more particularly to a traffic signal controller for automatically operating traffic signals in a predetermined timed sequence.
  • An object of the present invention is to provide a traiiic signal controller that is capable of being used in controlling cycles of operations that involve different numbers of steps or intervals.
  • Another object of the invention is to provide a traffic signal controller in which certain parts of the controller are standardized which results in economies in the manufacture and servicing of such controllers.
  • FIG. 2 is a rear view of the traffic signal controller illustrated in Fig. 1;
  • Fig. 3 is a side view of the traffic signal controller illustrated in Fig. l with certain parts broken away for clarity;
  • Fig.4 is a rear view showing details of the timing mechanism for the traffic signal controller illustrated in Fig. 1;
  • Fig.5 is a top view of the timing mechanism illustrated in Fig. 4; I
  • Fig. 6 is an end view of the driving mechanism illustrated in Figs. 4 and Fig. 7 is a schematic wiring diagram illustrating the electrical connections for certain parts of a traffic signal controller embodying the in- Vention;
  • Fig. 8 is' a front view of a dial for the traffic signal controller
  • FIG. 9 is a side view of an actuating key for use in the dial illustrated in Fig. 8;
  • Fig. 10 is 'a'section' view taken along the line Ill- 40 ofFig. 2;
  • Fig.- 11 is a side view of a switch member and contact assembly
  • Fig. 11 is'a plan view of the-switch member L illustrated inFig. l1;
  • Fig. l2 is a schematic wiring diagram illustratinganelectrical circuit for a traffic signal controller embodying the invention.
  • FIG. 1 there is a front panel I having an opening therein to accommodate a dial'Z, A rim 3 supporting a pane of glass is hinged to the panel I and encloses the opening in the panel I and the front of the dial 2.
  • dial 2- as -shown-in Figs. 5 and 6 consists of two I 2 spaced'plates 2a and 2b, each of which is provided with concentric rows of radial slots 4 and 5.
  • the radial slots 4 and 5 in the respective plates 2a and 2b are aligned to receive a contactactuating key 6 or 1 therein.
  • the contact-actuating keys 6 and I are short and long keys, respectively, and each key has a shank portion with a notch 8 formed at the base thereof in one edge of the key and a spring finger 9 positioned on the opposite edge of the key.
  • the notch 8 is held in engagement with the plate 2a at one end of the slot km 5 by the spring finger 9 pressing against the plate 2a at the opposite end of the slot 4 or 5.
  • This holds the keys 6 and I firmly in place in the' dial 2 but permits the keys to be readily removed from the dial 2 by forcing the key toward the center of the dial against the pressure of the spring finger 9 so as to disengage the notch 8 from the plate 211.
  • Such an arrangement allows the position of the keys 6 and I on the dial to be easily changed and eliminates the necessity of removing parts of the dial.
  • the dial 2 is secured to a shaft I0 that is rotatably mounted in a sleeve II;
  • the sleeve II is supported on a plate I2 that is secured to posts I3 extending from the rear of the panel I.
  • a gear I4 is removably secured to the end of the shaft I0 by a nut I5 so that the gear I4 can be readily changed to a gear of a different size when desired.
  • the gear I4 is normally in driving en'- gagement with a gear I6 that is carried on a' pivoted plate 11.
  • the plate I! is pivoted on the plate [2 by a shaft 24 that is rotatably supported thereon.
  • the pivoted plate IT has an arcuate slot I8 therein through which the shaft ID projects so that the pivoted plate I! may be moved arcuately to disengage the gear l6 carried thereon from the gear [4 when it is desired to replace the gear [4 with adifierent size gear.
  • the gear [4 may be easily changed when it is desired to change the speed of rotation for the dial 2.
  • the free end of the pivoted plate I! may serve as a pointer in cooperation with a scale I9 carried on the plate [2 that indicates the time for a complete revolution of the dial 2.
  • a second pointer 20 for indicating the time for a revolution of the dial 2 projects through an arcuate opening 2
  • the pointer 20 is carried by a bell crank-lever 23 that is pivotally supported on the plate I2 by the sleeve II.
  • a pin Ila carried by the plate I! extends through an arcuate slot in the plate I2 and engages with the end of the bell crank 23 to move it and the pointer when the position of the plate ll is changed.
  • the shaft 24 about which the plate I! pivots carries an intermediate gear that is engaged with the gear I6 carried on the pivoted plate IT.
  • the gear it remains in engagement with the gear 25 asth'e plate t! is, moved.
  • a driving gear 26 is secured to the drive shaft of a permanent magnet type of synchronous electric motor 21 which is non-coasting and eliminates the use of braking circuits or the like.
  • the drivinggear 26 engages with the gear 25 to drive the dial '2 through the gearing just described.
  • Themotor. 21. is removably secured to the plate 12 so that it may:
  • Micro-switches 29 and 39 are mounted ori the rear of the panel I above the dial 2 and have movable contact members 3
  • Theswitches 29 and. 3f aremounted on the rear of the panel I with their respective movable contact members 3
  • the long contact-actuatingkey l:- hasfa cut outportion m that permits'it topassv under without striking they contact memben 31 of. the switch 29, and the end of the key 1' raises the movable contact member 32. of switch 3.0 as the dial: 2 is rotated.
  • micro-switches maybe mounted in line with. the micro-switches 29; and 38- if they are required as. when. a master control systemis used and. suchmicrorswitches. may be operated by various length keys. carried: in theslots 5T of the dial 2.
  • rnicro-switch 29 by thecontact-actuating keys 6: momentarily; closes a, cir-. cuit; that will be describeldmore fully later, con-.. necting a solenoid '33" to a; source of electrical energy S.
  • The. solenoid. 33 which maybeof the typeshown in.PatentNo. 2,304,553, dated-Decemher 8; 1942, is looselymounted in a vertical posi-- tion on .therear'of the panel I by across pin 34.
  • the solenoid 33 is energizedmomentarily as: by the closing of the microeswitch.
  • the end ofthe plunger 3150f the solenoid 33: is connected'to a weighted: arm 36 which is; raised and lowered with the plunger 35.
  • the armgifi pivotedon one of the supporting brackrets. 31 located at right angles to the rear'face of the panel I. at the-ends thereof.
  • the arm 36 carries, a pawl 3B'and a stop. 39that engage with a toothedratchet wheel 4U.
  • the toothed ratchet wheel 48 is secured to a cam shaft 4
  • The; stop 39g engageslwith the; top of the ratchet wheel to holdthe ratchet wheel 40 andto limit the distance that, the pawl 33: can move the ratchet wheel 49 and cam shaft 4:! for eachoperation of the solenoid 33.v
  • the stop 39. maybe designed so that different movements of the ratchet Wheel 40 in response to operation of: the solenoid 33 may be obtained by reversing the position of the stop 39 on the arm 3.6.
  • the adjustable stop 39 may be positioned so that the ratchet wheel 40 will be advanced a distance corresponding to one tooth for each operation of the solenoid 33 or in eighteen steps for a complete revolution of the ratchet wheel 68, or the stop 39rmay be reversedg so that the ratchet wheel 30 will beadvanced a distance corresponding to two teeth for each operation of the solenoid 33 or in nine steps for a complete revolution.
  • the ratchet wheel 40 is provided with a number of teeth corresponding to the greatest-possible number of periods or signal intervals that may be required under any ordinary conditions. If fewer signal intervals are required in a particular installation, a number of signal operating cycles may be accomplished in a compl te vo io of he; ams aft 4.1; and unde ch. tio t re l 'be ss W a anti-tear on the cam shaft 41-.
  • irra e ne l t n he w iehr nere na earns m be m e a: im s e nsl t ns; m er al i th o o cir r sc; with. a series of wedge-shaped segments 43 correspond; ing in number; to the teeth ontherat chet wheel; 46 spac d; a nd: 5: Q teedrc mfe en a 1531 of, as shown in Fig.
  • a 11111344 isprovidedqn each of; the switch-operating cams 42 and extendsagrially from one face of the camso as to-position-anad jacent cam in, properly spaced relation; when the cams are assembled on the shaft 4]
  • terminals 46 when assembled on the; cam shaft 41, respectively, supporttheends of 1 a series of switch members; 45 a; to 451, inclusive; referred togenerally as -S Wi h;- mem e s 5- The i h rnimrlbersv e-re ovably supported on terminals Matte-462', inclusive, referred to generally as terminals 46;.
  • Theter minals 46 are carried on a bar qf'insulatingmaa terial 4; ⁇ that issupported by the brackets; 37.
  • the switch members 435- are; held; in; contact-with the terminals 46' and in engagement, with the cams 42 by springs 48 carried on a post 48a;ex-.
  • The. ends off-the switch members 45 are bifurcated; and; have legs s that may be slid benea the bd o h s rin 33 on either side of the post-48 a contacting; engagement with the'terininal 46.
  • a fla e mechamsmtt is associated with the timing motor 21 and consists of a toothed wheel 54 that is secured to the shaft 24 which is driven by the timing motor 21.
  • toothed wheel 54 engages with the end of a terminals 55a and 5811.
  • the contacts 56 and 51 are opened and closed by the flexible contact-carrying member 55 riding over the toothed portions of the wheel 54.
  • and their respective switch members 45a, 45b and 450, are shown in Fig. 7. These circuits control the operation of the solenoid 33 and movement of the cam shaft 4
  • the remainder of the switch-operating cams 42d to 421 with their respective switch members 45d to 451' in cooperation with the terminals 52d to 52i control the operation or display of the traffic signals or lights.
  • a traific signal system having four periods or intervals of operation has been described.
  • a traffic signal having green, amber and red signals or lights, indicated by reference characters G1, A1 and R1, respectively, for the main street and green, amber and red signals, indicated by the reference characters G2, A2 and R2, respectively, for the cross street.
  • the operation of the traffic signal in a four interval system requires four movements or steps of the cam shaft 41 and the switch-operating cams 42 carried thereon and the switch-operating cams 42 are de-- signed so that during the first interval, the signal G1 (green) for the main street and the signal R2 (red) for the cross street are displayed; during the second interval, the signal A1 (amber) 'for the main street and the signal Ra (red) for the cross street are displayed; during the third intervals, the signal R1 (red) for the main street and the signal G2 (green) for the cross street are displayed; and during the fourth interval, the signal R1 (red) for the main street and the signal A2 (amber) for the cross street are displayed.
  • switch-operating cams 42a. to 421' respectively, by breaking out appropriate segments 43 of the switch-operating cams 42d to 422' so that the switch members 4511 to 452, which control the circuits connecting the traffic signals to the source of electrical energy S as shown in Fig. 12, are opened and closed at the proper time as the cam shaft 4
  • and 32 of the micro-switches 29 and 30 are connected to one side of the solenoid 33 and the other side of the solenoid 33 is connected to the common or ground side C of the source of electrical energy S.
  • the fixed contacts 29 and 30' of the micro-switches 29 and 30, respectively, are connected to the power side P of the source of electrical energy S through the switch members 45a and 45b, respectively in cooperation with the terminals 52a and 521).
  • the solenoid 33 is connectedto power side P of the source of electrical energy S through the switch member 450 in cooperation with the terminal 520 and the flasher mechanism 6
  • the cams 42a and 42b controlling the switch members 45a and 45b are arranged so that each time the key 6 closes the contacts 3
  • the cams 42a and 42b are arranged so that whenever the switch member 4511 is open the switch member 45b will be closed and, thus, the condition where the keys 6 do not close the circuit to the solenoid 33 will continue until the key closes the contacts of the micro-switch 3!] to complete a circuit connecting the solenoid 33 to the source of electrical energy S which causes the solenoid 33 to move the cam shaft 4
  • permits the switch member 45a to close and thereafter the cam shaft 4
  • at which the switch member 4511 is held open may be coordinated with the cams 4511 to 451' controlling the traffic signals so that the period during which the controller is in this position will occur when the signals G1 (green) for the main street and R2 (red) for the cross street are displayed so that any delay will not affect the main flow of traffic.
  • cam shaft may be moved any additional steps that may be required
  • a switch fi'l in a cireuit connecting the timing 'motor Zlt'o the source'of electricalienergy S- may be located on the front of the :panel' I to: permit *the timing motor to be starte'd'or stoppedasadesiredfi
  • 63A switchscfil may :Lbe mmridedixin ::the-..;circuit .-wi'th thezterminalsa52cl;to.52iconnecting theTi-I'fifr fie-signals to thesourceof electrical-.energy-rfiand itheswitch afili-maysalso be located zonutherfnont offiheupanelnl A-removable co.v.er;-1i 8 rmamalso loe-provided to; enclose ithe: sides. and: tonof the controller. l
  • a traffic signal controller of the type described wherein a display of trafiic signals is controlled by a rotary switching mechanism the combination of a rotatable shaft supporting said rotary switching mechanism, electrically operated means connected to the shaft for rotating the shaft in step by step movements, the number of said movements required for a complete revolution of said shaft being in excess of the number of said movements required for at least one complete cycle of traffio signal displays, a circuit controlled by a constantly rotating timing dial for operating the shaft rotating means and a second circuit for operating said shaft rotating means, said second circuit including a switch operable by rotation of the shaft and a switch 10 operable by rotation of the timing dial, said lastmentioned switch being operated anumber of times during a singlerevolution of the timing dial, the number of switch operations being at least equal to the number of movements of the shaft in excess of the number of movements required for the trafiic signal displays required for a complete revolution thereof.
  • the electrically operated means for rotating the shaft includes a ratchet wheelsecured to the shaft and a solenoid, the solenoid having a plunger engaging with a tooth on the ratchet wheel and advancing the ratchet wheel and shaft one step upon each energization of the solenoid.
  • the electrically operated means for rotating the shaft includes a ratchet wheel secured to the shaft, said ratchet wheel having at least eighteen teeth thereon and a solenoid, the solenoid having a plunger engaging with a tooth on the ratchet wheel and advancing the ratchet wheel and shaft one step upon each energization of the solenoid.
  • the combination as defined in claim 4 wherein the last-mentioned switch controlled by the timing dial consists of a flasher mechanism connected to and driven with the timing dial.
  • a traffic signal controller of the type described including a rotary switching mechanism for controlling a display of traffic signals in a predetermined sequence, said rotary switching mechanism controlling a plurality of cycles of the sequential traffic signal displays during each revolution thereof, a motor driven timing dial for causing step by step movement of the rotary switching mechanism at selected intervals of time with a complete cycle of traflic signal displays being accomplished in a single revolution of said dial and a second rotary switching mechanism operable by said timing dial in the operation of the first rotary switching mechanism and means for causing the step by step movements of both of the rotary siwtching mechanisms for the steps required to complete one revolution of the first-mentioned rotary switching mechanism in addition to the step by step movements thereof required for the number of complete traiiic signal display cycles during each revolution of the first-named rotary switching mechanism, said means including an intermittently operated circuit making and breaking mechanism operable by rotation of the motor operated timing dial, said circuit making and breaking mechanism being in a circuit controlled by said second rotary switching mechanism.
  • a trafiic signal controller of the type described including a rotary switching mechanism for controlling a trafiic signal display in a predetermined sequence, said rotary switching mechanism being capable of operating the sequential traffic signal display in a plurality of cycles during each revolution thereof of said switching mechanism, means including a continuously rotating motor driven timing dial for causing step by step movement of the rotary switching mechanism at selected intervals of time with a complete sequence of trafiic signal displays being accomplished in a single revolution of said dial, a second rotary switching mechanism connected to and driven with the first rotan? switching mechanism, said second switching mechanism being: rendered operable by the timing dial in the operation of the first rotary switching mechanism. and an intermittently operated circuit making and breaking mechanism eperabie' by the timing dia'L.
  • circuit making and breaking mechanism being connected in a circuit with the second rotary switching means and the means for advancing the rotary switching' mechanisms to automatically advance both of the rotary switching mechanisms in a. single revolution: of the timing dial a. number of steps in addition to the number of steps thereof actuated by the motor'driventiming dial, said additional steps plus the first-mentioned steps thereof "being equal to the number of steps required for a complete revolution of the first-mentioned rotaryswitching'mechanism.

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  • General Physics & Mathematics (AREA)
  • Rotary Switch, Piano Key Switch, And Lever Switch (AREA)

Description

Sept. 2, 1952 A. DIEBOLD TRAFFIC SIGNAL CONTROLLER 4 Sheets-Sheet 1 Filed May 15, 1948 J/yna/ Aufo Run 6'? Off lkmd Resyn VINVENTOR. 4/710/7 0 /'6 60/0 ATTORNEYS Sept. 2, 1952 A. DIEBOLD TRAFFIC SIGNAL CONTROLLER Filed May 13, 1948 fin/an INVENTOR. i i
A TTORA/[YS Sept. 2, 1952 A. DIEBOLD TRAFFIC SIGNAL CONTROLLER Filed May 13, 1948 4 Sheets-Sheet 3 an RN Sept. 2, 1952 A. DIEBOLD TRAFFIC SIGNAL CONTROLLER Filed May 15, 1948 4-Sheets-Sheet 4 ATTORNEYJ Patented Sept. 2, 1952 TRAFFIC SIGNAL CONTROLLER Anton Diebold, New York, N. Y., assignor to The Marbelite Company, Inc., New York, N. Y., a
corporation of New York Application May 13, 1948, Serial No. 26,814
10 Claims. 1
The present invention relates to improvements in traffic signal controllers and relates more particularly to a traffic signal controller for automatically operating traffic signals in a predetermined timed sequence.
An object of the present invention is to provide a traiiic signal controller that is capable of being used in controlling cycles of operations that involve different numbers of steps or intervals. Another object of the invention is to provide a traffic signal controller in which certain parts of the controller are standardized which results in economies in the manufacture and servicing of such controllers. Various other objects and advantages of the present invention will be apparent and best understood from the following description and the accompanying drawings in whichi Fig. l is a front view of a traffic signal controller embodying the invention;
"Fig. 2 is a rear view of the traffic signal controller illustrated in Fig. 1;
Fig. 3 is a side view of the traffic signal controller illustrated in Fig. l with certain parts broken away for clarity;
Fig.4 is a rear view showing details of the timing mechanism for the traffic signal controller illustrated in Fig. 1;
Fig.5 is a top view of the timing mechanism illustrated in Fig. 4; I
Fig. 6 is an end view of the driving mechanism illustrated in Figs. 4 and Fig. 7 is a schematic wiring diagram illustrating the electrical connections for certain parts of a traffic signal controller embodying the in- Vention;
' Fig. 8 is' a front view of a dial for the traffic signal controller;
' Fig; 9 is a side view of an actuating key for use in the dial illustrated in Fig. 8;
, Fig. 10 is 'a'section' view taken along the line Ill- 40 ofFig. 2;
Fig.- 11 is a side view of a switch member and contact assembly;
Fig. 11 is'a plan view of the-switch member L illustrated inFig. l1; and
" Fig. l2 is a schematic wiring diagram illustratinganelectrical circuit for a traffic signal controller embodying the invention.
*As shown in Fig. 1, there is a front panel I having an opening therein to accommodate a dial'Z, A rim 3 supporting a pane of glass is hinged to the panel I and encloses the opening in the panel I and the front of the dial 2. The
dial 2-, as -shown-in Figs. 5 and 6 consists of two I 2 spaced'plates 2a and 2b, each of which is provided with concentric rows of radial slots 4 and 5. The radial slots 4 and 5 in the respective plates 2a and 2b are aligned to receive a contactactuating key 6 or 1 therein.
The contact-actuating keys 6 and I are short and long keys, respectively, and each key has a shank portion with a notch 8 formed at the base thereof in one edge of the key and a spring finger 9 positioned on the opposite edge of the key. When the keys 6 or I are inserted in the slots 4 or 5, the notch 8 is held in engagement with the plate 2a at one end of the slot km 5 by the spring finger 9 pressing against the plate 2a at the opposite end of the slot 4 or 5. This holds the keys 6 and I firmly in place in the' dial 2, but permits the keys to be readily removed from the dial 2 by forcing the key toward the center of the dial against the pressure of the spring finger 9 so as to disengage the notch 8 from the plate 211. Such an arrangement allows the position of the keys 6 and I on the dial to be easily changed and eliminates the necessity of removing parts of the dial.
The dial 2 is secured to a shaft I0 that is rotatably mounted in a sleeve II; The sleeve II is supported on a plate I2 that is secured to posts I3 extending from the rear of the panel I. A gear I4 is removably secured to the end of the shaft I0 by a nut I5 so that the gear I4 can be readily changed to a gear of a different size when desired. The gear I4 is normally in driving en'- gagement with a gear I6 that is carried on a' pivoted plate 11. The plate I! is pivoted on the plate [2 by a shaft 24 that is rotatably supported thereon. The pivoted plate IT has an arcuate slot I8 therein through which the shaft ID projects so that the pivoted plate I! may be moved arcuately to disengage the gear l6 carried thereon from the gear [4 when it is desired to replace the gear [4 with adifierent size gear. Thus, the gear [4 may be easily changed when it is desired to change the speed of rotation for the dial 2.
The free end of the pivoted plate I! may serve as a pointer in cooperation with a scale I9 carried on the plate [2 that indicates the time for a complete revolution of the dial 2. A second pointer 20 for indicating the time for a revolution of the dial 2 projects through an arcuate opening 2| in the panel I beneath the dial 2 and registers with a scale 22 located on the front of the panel. The pointer 20 is carried by a bell crank-lever 23 that is pivotally supported on the plate I2 by the sleeve II. A pin Ila carried by the plate I! extends through an arcuate slot in the plate I2 and engages with the end of the bell crank 23 to move it and the pointer when the position of the plate ll is changed.
The shaft 24 about which the plate I! pivots carries an intermediate gear that is engaged with the gear I6 carried on the pivoted plate IT. The gear it remains in engagement with the gear 25 asth'e plate t! is, moved. A driving gear 26 is secured to the drive shaft of a permanent magnet type of synchronous electric motor 21 which is non-coasting and eliminates the use of braking circuits or the like. The drivinggear 26 engages with the gear 25 to drive the dial '2 through the gearing just described. Themotor. 21. is removably secured to the plate 12 so that it may:
be replaced if necessary at any time.
Micro-switches 29 and 39 are mounted ori the rear of the panel I above the dial 2 and have movable contact members 3| and 32, respectively, associated therewith. The micro-switches 29 and:.30=. areconnectedr. in electrical circuits; that.
cause; theaadva-nce of a; signal controllingmechanisrn and .also insure. proper. coordination between the operation of: the dial- Zandthesignal controlling mechanism. as: will be described later. Theswitches 29 and. 3f aremounted on the rear of the panel I with their respective movable contact members 3| and. 32 in staggered: relation to each other so that the ends. of' the short contactactuating; keys 6 will raisethe movable contactmember 3A of switch 29, but do not strike the movable contact member 32 of the switch 39 as thedial-Z is. rotated. The long contact-actuatingkey l:- hasfa cut outportion m that permits'it topassv under without striking they contact memben 31 of. the switch 29, and the end of the key 1' raises the movable contact member 32. of switch 3.0 as the dial: 2 is rotated.
Additional micro-switches maybe mounted in line with. the micro-switches 29; and 38- if they are required as. when. a master control systemis used and. suchmicrorswitches. may be operated by various length keys. carried: in theslots 5T of the dial 2.
The operation of rnicro-switch 29 by thecontact-actuating keys 6: momentarily; closes a, cir-. cuit; that will be describeldmore fully later, con-.. necting a solenoid '33" to a; source of electrical energy S. The. solenoid. 33; which maybeof the typeshown in.PatentNo. 2,304,553, dated-Decemher 8; 1942, is looselymounted in a vertical posi-- tion on .therear'of the panel I by across pin 34. When the solenoid 33 is energizedmomentarily as: by the closing of the microeswitch. contacts, its plunger 35 is raised to its upward position and when the contacts of the micro-switch 29 or- 30 open, the plunger is permitted to fall by gravity. The end ofthe plunger 3150f the solenoid 33: is connected'to a weighted: arm 36 which is; raised and lowered with the plunger 35. 'The armgifiis pivotedon one of the supporting brackrets. 31 located at right angles to the rear'face of the panel I. at the-ends thereof. The arm 36 carries, a pawl 3B'and a stop. 39that engage with a toothedratchet wheel 4U. The toothed ratchet wheel 48 is secured to a cam shaft 4|; that isrotatably supported at its ends in the brackets 37-.
The; stop 39gengageslwith the; top of the ratchet wheel to holdthe ratchet wheel 40 andto limit the distance that, the pawl 33: can move the ratchet wheel 49 and cam shaft 4:! for eachoperation of the solenoid 33.v The stop 39. maybe designed so that different movements of the ratchet Wheel 40 in response to operation of: the solenoid 33 may be obtained by reversing the position of the stop 39 on the arm 3.6. Thus, if the ratchet wheel 40 is providedwith eighteen teeth, as illustrated, the adjustable stop 39 may be positioned so that the ratchet wheel 40 will be advanced a distance corresponding to one tooth for each operation of the solenoid 33 or in eighteen steps for a complete revolution of the ratchet wheel 68, or the stop 39rmay be reversedg so that the ratchet wheel 30 will beadvanced a distance corresponding to two teeth for each operation of the solenoid 33 or in nine steps for a complete revolution.
In a traffic signal controller embodying the present invention, the ratchet wheel 40 is provided with a number of teeth corresponding to the greatest-possible number of periods or signal intervals that may be required under any ordinary conditions. If fewer signal intervals are required in a particular installation, a number of signal operating cycles may be accomplished in a compl te vo io of he; ams aft 4.1; and unde ch. tio t re l 'be ss W a anti-tear on the cam shaft 41-.
T e c m sha t-i a r es; a S ie 0t sw t h: operating cams 42a to fifii irclusive, that will be. referred to generallyasswi-tch operating. cams The am c r n e on of he haft-.4 is square with one corner beveled-toserveasguide inassembling the earns 62 onthe shaft. 41 irra e ne l t n he w iehr nere na earns m be m e a: im s e nsl t ns; m er al i th o o cir r sc; with. a series of wedge-shaped segments 43 correspond; ing in number; to the teeth ontherat chet wheel; 46 spac d; a nd: 5: Q teedrc mfe en a 1531 of, as shown in Fig. 10-.- V e v eed e me s; may e: bered and selected segments may be broker-tout either before'or; after assembly of; the cams on the cam shaft. A 11111344: isprovidedqn each of; the switch-operating cams 42 and extendsagrially from one face of the camso as to-position-anad jacent cam in, properly spaced relation; when the cams are assembled on the shaft 4] The switch-operating cams; 42a. to. 422', when assembled on the; cam shaft 41, respectively, supporttheends of 1 a series of switch members; 45 a; to 451, inclusive; referred togenerally as -S Wi h;- mem e s 5- The i h rnimrlbersv e-re ovably supported on terminals Matte-462', inclusive, referred to generally as terminals 46;. Theter minals 46 are carried on a bar qf'insulatingmaa terial 4;} that issupported by the brackets; 37. The switch members 435- are; held; in; contact-with the terminals 46' and in engagement, with the cams 42 by springs 48 carried on a post 48a;ex-. tendingfrom the terminals 46,, The. ends off-the switch members 45 are bifurcated; and; have legs s that may be slid benea the bd o h s rin 33 on either side of the post-48 a contacting; engagement with the'terininal 46.
When the end of one of the switchmembers, registers with a; portion of a. switch-operating cam 42 where one of the segmentsl ihas been. broken out, the spring 43 urg esthe. switch member 5 to the position illustrated in Fig; 11. When; the switch member #5 is in..thi s position, a contact button 5t carried thereon contactswith a contact button 5! carried onasecond terminal52 toclose anelectrical circuit that will bedescribedhereinafter; A. series of the:term inals 5 2 indicated by; reference numerals 52a to, 522 are; carried'on a; con ar. o s la n erial. .3.: at i so. supportediby the bra kets 31-.
Asshown in Big. 2;. a fla e mechamsmtt is associated with the timing motor 21 and consists of a toothed wheel 54 that is secured to the shaft 24 which is driven by the timing motor 21. The
toothed wheel 54 engages with the end of a terminals 55a and 5811. When the toothed wheel 54 is rotated by the timing motor 21 the contacts 56 and 51 are opened and closed by the flexible contact-carrying member 55 riding over the toothed portions of the wheel 54.
The electrical circuits controlled by the first three switch- operating cams 42a, 42b and 420 on the cam shaft 4| and their respective switch members 45a, 45b and 450, are shown in Fig. 7. These circuits control the operation of the solenoid 33 and movement of the cam shaft 4| in response thereto. The remainder of the switch-operating cams 42d to 421 with their respective switch members 45d to 451' in cooperation with the terminals 52d to 52i control the operation or display of the traffic signals or lights.
For the purposes of illustration, a traific signal system having four periods or intervals of operation has been described. In such a system, there is a traffic signal having green, amber and red signals or lights, indicated by reference characters G1, A1 and R1, respectively, for the main street and green, amber and red signals, indicated by the reference characters G2, A2 and R2, respectively, for the cross street. The operation of the traffic signal in a four interval system requires four movements or steps of the cam shaft 41 and the switch-operating cams 42 carried thereon and the switch-operating cams 42 are de-- signed so that during the first interval, the signal G1 (green) for the main street and the signal R2 (red) for the cross street are displayed; during the second interval, the signal A1 (amber) 'for the main street and the signal Ra (red) for the cross street are displayed; during the third intervals, the signal R1 (red) for the main street and the signal G2 (green) for the cross street are displayed; and during the fourth interval, the signal R1 (red) for the main street and the signal A2 (amber) for the cross street are displayed. The display of the trailic signals G1, A1, R1, G2, A2
and R2 in the desired sequence is controlled by the switch-operating cams 42a. to 421', respectively, by breaking out appropriate segments 43 of the switch-operating cams 42d to 422' so that the switch members 4511 to 452, which control the circuits connecting the traffic signals to the source of electrical energy S as shown in Fig. 12, are opened and closed at the proper time as the cam shaft 4| is rotated.
Referring now to the electrical circuits for the controller illustrated in Fig. '7, the movable contacts 3| and 32 of the micro-switches 29 and 30 are connected to one side of the solenoid 33 and the other side of the solenoid 33 is connected to the common or ground side C of the source of electrical energy S. The fixed contacts 29 and 30' of the micro-switches 29 and 30, respectively, are connected to the power side P of the source of electrical energy S through the switch members 45a and 45b, respectively in cooperation with the terminals 52a and 521). In addition, the solenoid 33 is connectedto power side P of the source of electrical energy S through the switch member 450 in cooperation with the terminal 520 and the flasher mechanism 6 The cams 42a and 42b controlling the switch members 45a and 45b are arranged so that each time the key 6 closes the contacts 3| and 29 of the micro-switch 29 and each time the key I closes the contacts 32 and 35' of the micro-switch 30, the solenoid 33 will be momentarily connected to the source of electrical energy S and in response thereto will be operated to move the cam shaft 4| one step.
However, if the cam shaft 4| and the timing dial 2 are not operatin in proper coordination for the desired signal sequence, as may happen when the controller has been operated manually without regard to the position of the dial, a point is reached where the cam 42a holds the switch member 45a open so that the operation of the micro-switch 29 by the keys 5 does not close the circuit connecting solenoid 33 to the source of electrical energy S. The cams 42a and 42b are arranged so that whenever the switch member 4511 is open the switch member 45b will be closed and, thus, the condition where the keys 6 do not close the circuit to the solenoid 33 will continue until the key closes the contacts of the micro-switch 3!] to complete a circuit connecting the solenoid 33 to the source of electrical energy S which causes the solenoid 33 to move the cam shaft 4| one step. This movement of the cam shaft 4| permits the switch member 45a to close and thereafter the cam shaft 4| will operate in response to the keys 6 or 1 closing the contacts of either the micro-switches The position of the cam shaft 4| at which the switch member 4511 is held open may be coordinated with the cams 4511 to 451' controlling the traffic signals so that the period during which the controller is in this position will occur when the signals G1 (green) for the main street and R2 (red) for the cross street are displayed so that any delay will not affect the main flow of traffic.
When the traffic signals are operated in four interval system, as in the example described, four cycles or a total of sixteen intervals may be accomplished during each revolution of the cam shaft 4|. In such case, the camshaft 4| is automatically advanced two additional steps required for a complete revolution on the basis of the eighteen toothed ratchet wheel 49. This is accomplished by permitting the switch member 450 to close during two steps of the cam shaft 4|. When the switch member 450 is closed in relation to its terminal 520, the solenoid 33 will be momentarily connected to the source of electrical energy S by the operation of'the flasher mechanism 6|. The other cams 42 on the cam shaft 4| are designed so that this movement of the cam shaft 4| does not affect the circuits controlled by them.
By this arrangement the cam shaft may be moved any additional steps that may be required,
depending upon the number of intervals used.
clearly divisible into the eighteen step movement mits any change or: alteration of; the "cycle 1 toibe i'or each ratchet wheel in constructing-controllers for a' num-ber: ofintervals. ln lsuchzaucontroller whenit is desired to "change the numbernfiinterval's afterthe controller was-assembled; the-solenoidplungerand-operating tpaittseassdciatd.
therewith had' to' :be changed-accordingly. :eThis ialso'made it necessar-yf or 'repairnand maintenance 'men to car-ryawariety of size oflthesameuparts 'to' repair such' controllers.
i A switch fi'l in a cireuit connecting the timing 'motor Zlt'o the source'of electricalienergy S-may be located on the front of the :panel' I to: permit *the timing motor to be starte'd'or stoppedasadesiredfi A 2 double throw -swit'ch- 63 inonenclosed position" connects the: solenoid 33 in circuit :with the source of electrical energy S through them- --"cro-' swit'ches 29 and 30 for automatic operation and inkthe other closedposition connects' the solenoid 33= to the source 'of :electrical energy 'S -'through-- a manual- 1y -operablepush button type {of "-switch' -64 *for manual -op er'atio n. Theswitch 63-ior-control1ing the automatic 'for-manual-ope gation grnay'alsobe located on-thefront of thepan'el liar convenience.
When the switch 631s in manual positiom the solenoid33 is connected tothe'sourcebf electri- :fc'aluenereyf each t m t m t n w hi fi is .fcloseiii iThe solenoid 33' in r e spon se 'thereto moves-the .camshaft A I one step causingthesig- \nali display to be changed. "i However, whenf'the gcontrollerl is operatedJoyz manual controlswitch -lit -lithe .cireuit through the, switch .memberi-fetig: and the,flasher-mechanismBI continuesitooper- \ateras-usual and automatically advances the cam -=,shaft :41, in the manner previouslyadescribed, ior
such :steps of the cam shaft- 4 I; asth ere-maybe dur itsaev luti w ere -c ang B 25 5 na l display takes place; i. e; the additional steps zfona complete reVolu-tionpf-the cam shait l 212 ferredmtoabove. @Thus, seachzop r tion of :the epushlbutton' switch16.4 causes a zchaingegim thexsigr nal display.
Inaddition tothe-controrswitehes.62 and-;63, a four pole; itriple ihlDWiSWitChifiEiiS? provided'rand lmay be ilocated onza' separate panelzboard 1166. One position of the switch? I65 'connectsiithecon- -+tro11er tothe source of electrical energy 'Sso-that 'it'may be: operated automatically or imanuallyfin "the manner described above. In the "second cor "inhronghithe Tfiashemechanismi 6 lrsoithatfm signalswillbadisplayeddntermittently.
63A switchscfil may :Lbe mmridedixin ::the-..;circuit .-wi'th thezterminalsa52cl;to.52iconnecting theTi-I'fifr fie-signals to thesourceof electrical-.energy-rfiand itheswitch afili-maysalso be located zonutherfnont offiheupanelnl A-removable co.v.er;-1i 8 rmamalso loe-provided to; enclose ithe: sides. and: tonof the controller. l
1 It"willzbeiunderstood thatv thoselskilledi-imtbe art: may make various'modifications -.and.:chan es in the .controllerithathas beenkiilustratedeassiembod-yingzthe present invention:without Ldeparting from thescope ofithe invention; asideflnedin-Ithe *elaims appended' hereto.
claim:
1. In a traffic signakcontroller of' the'typehavone a rotary switching. mechanismfor controlling the displayof traffic-signals atan -intersection in a=-predetermined sequence withan -:-e1ectrica-1ly operated driving means for-advancing saidrotary switching mechanism in step-by step movements in response-to the actuaticn by a timing a dial of --switcheseonnecting the electrically operated driving -meansto a source of electrical -energy, the -combination comprisinga switching -mechanism -'-operable by the -electricallyoperated driving mechanismand a fiashermechanism operated independently of -"said 1 driving"mechanism said switching 'mechanism and said fiasher mechanism beingin-a-lcircuit*connecting thedriving means 'to asource'of-electrical energy wherebysaid driv- "ing -meansis intermittently operated by said "flasher-mechanism when said switchingmechanism is closed.
l -Ina traifid-signal-control1er-of the type described,' the-combination of {a 'rotary' switch mechanism controllingcircuits 'for operating a display-of trafiic signals in apredetermined -se- -quence, said-rotary switch mechanism--maintaininganeXisting 'tra-ilic signa1- display at a-nuinber of=-consecutive-positions thereof, -a solenoid for driving said rotary switch-mechanism in step by step-movement in cont'rolling said circuits," a pair of switchesfi parallel circuits connecting said gsolenoid td-afsource ofelectrical energy, a motor *driventimingi dialassociated with said switches iort operating" said switches at timed-"intervals "thereby causing-said' solenoid to operate and-ad- :vance therrotary'switch mechanism; a-swigtching device in circuit-'with'one of said switches a secondyswitchingsdevice incircuit with the'othemof said switches, both of said switq ngdevices; being fdrivembythe solenoid in" conjunction" with the rotary'switch' mechanism and being arranged to open the circuit to 'one' switch when the circuit to theotherswitch isclosed whereby the rotary switch mechanism will be advanced one step upon the actuation. of either switch by the timing dial whenihejdialjis rotating in properly coordinated relation to said switching devices, a'third switchin device driven by said solenoid. andnalcircuit makm and 1, breakin mechanism; sa d jthird switching device and ,said, circuit making, and 'br ak ne;dovicehein in a circuit lconnectingsaid solenoid ;to the, source of electrical energy, said third switching [device being arranged to .close said'flast' mentioned' circuit andtherebyautomati cal'ly" render" the circuit making and "breaking device on orative; said circuit making and breakir g-devicebeing :operable in a single revolution "v f h i m n ia t a v n th a w tch mechanism. .a'; number ;of stepsyponithegccrnple- 'tion of an even multiple ofthe revolutions ofjt'he timing dial" "and at atime when 'rotaryswitch 59 mechanism maintains the existing traiiic' signal display in a number of consecutive positions there- 'of, said last-mentioned number of steps plusthe switches in parallel circuits connecting said solenoid to a source of electrical energy, a motor driven timing dial associated with said switches for operating said switches at timed intervals thereby causing said solenoid to operate and advance the rotary switch mechanism, a switching device in circuit with one of said switches, a second switching device in circuit with the other of said switches, both of said switching devices being driven by the solenoid in conjunction with the rotary switch mechanism and being arranged to open the circuit to one switch when the circuit to the other switch is closed whereby the rotary switch mechanism will be advanced one step upon the actuation of either switch by the timing dial when the dial is rotating in properly coordinated relation to said switching devices, a third switching' device driven by said solenoid, a circuit making and breaking mechanism, said third switching device and said circuit making and breaking device being in a circuit connecting said solenoid to the source of electrical energy, said third switching device being arranged to close said last-mentioned circuit and thereby automatically render the circuit making and breaking device operative, said circuit making and breaking device being operable in a single revolution of the timing dial to advance the rotary switch mechanism a number of steps upon the completion of an even multiple of the revolutions of the timing dial and at a time when the rotary switch mechanism maintains the existing traffic signal display in a number of consecutive positions thereof, said last-mentioned number of steps plus the number of steps of the rotary switch mechanism actuated by the timing dial being equal to the number of steps required for one complete revolution of the rotary switch mechanism, a manually operable push button switch in a circuit connecting said solenoid to the source of electrical energy and a switch for selectively connecting said solenoid to said push button switch and to the dial operated switches.
4. In a traffic signal controller of the type described wherein a display of trafiic signals is controlled by a rotary switching mechanism, the combination of a rotatable shaft supporting said rotary switching mechanism, electrically operated means connected to the shaft for rotating the shaft in step by step movements, the number of said movements required for a complete revolution of said shaft being in excess of the number of said movements required for at least one complete cycle of traffio signal displays, a circuit controlled by a constantly rotating timing dial for operating the shaft rotating means and a second circuit for operating said shaft rotating means, said second circuit including a switch operable by rotation of the shaft and a switch 10 operable by rotation of the timing dial, said lastmentioned switch being operated anumber of times during a singlerevolution of the timing dial, the number of switch operations being at least equal to the number of movements of the shaft in excess of the number of movements required for the trafiic signal displays required for a complete revolution thereof. 1
5. In a trafllc signal controller of the type described, the combination as defined in claim 4 wherein the electrically operated means for rotating the shaft includes a ratchet wheelsecured to the shaft and a solenoid, the solenoid having a plunger engaging with a tooth on the ratchet wheel and advancing the ratchet wheel and shaft one step upon each energization of the solenoid.
6; In a trafiic signal controller of the type described, the combination as definedin claim 4 wherein the electrically operated means for rotating the shaft includes a ratchet wheel secured to the shaft, said ratchet wheel having at least eighteen teeth thereon and a solenoid, the solenoid having a plunger engaging with a tooth on the ratchet wheel and advancing the ratchet wheel and shaft one step upon each energization of the solenoid.
'Z. In a traiiic signal controller of the type described, the combination as defined in claim 4 wherein the last-mentioned switch controlled by the timing dial consists of a flasher mechanism connected to and driven with the timing dial.
8. In a traffic signal controller of the type described, the combination including a rotary switching mechanism for controlling a display of traffic signals in a predetermined sequence, said rotary switching mechanism controlling a plurality of cycles of the sequential traffic signal displays during each revolution thereof, a motor driven timing dial for causing step by step movement of the rotary switching mechanism at selected intervals of time with a complete cycle of traflic signal displays being accomplished in a single revolution of said dial and a second rotary switching mechanism operable by said timing dial in the operation of the first rotary switching mechanism and means for causing the step by step movements of both of the rotary siwtching mechanisms for the steps required to complete one revolution of the first-mentioned rotary switching mechanism in addition to the step by step movements thereof required for the number of complete traiiic signal display cycles during each revolution of the first-named rotary switching mechanism, said means including an intermittently operated circuit making and breaking mechanism operable by rotation of the motor operated timing dial, said circuit making and breaking mechanism being in a circuit controlled by said second rotary switching mechanism.
9. In a trafiic signal controller of the type described, the combination including a rotary switching mechanism for controlling a trafiic signal display in a predetermined sequence, said rotary switching mechanism being capable of operating the sequential traffic signal display in a plurality of cycles during each revolution thereof of said switching mechanism, means including a continuously rotating motor driven timing dial for causing step by step movement of the rotary switching mechanism at selected intervals of time with a complete sequence of trafiic signal displays being accomplished in a single revolution of said dial, a second rotary switching mechanism connected to and driven with the first rotan? switching mechanism, said second switching mechanism being: rendered operable by the timing dial in the operation of the first rotary switching mechanism. and an intermittently operated circuit making and breaking mechanism eperabie' by the timing dia'L. said circuit making and breaking mechanism being connected in a circuit with the second rotary switching means and the means for advancing the rotary switching' mechanisms to automatically advance both of the rotary switching mechanisms in a. single revolution: of the timing dial a. number of steps in addition to the number of steps thereof actuated by the motor'driventiming dial, said additional steps plus the first-mentioned steps thereof "being equal to the number of steps required for a complete revolution of the first-mentioned rotaryswitching'mechanism.-
10. 111 a traffic signal sOIltIOHEl or the type ANTON 'DIEBOLII REFERENCES CITED The following references are of recordiin the tile" of this patent:
STATES PATENTS Number Name a Date 1,490,557 Kleinsfieuber Apr. 15, 1 924 1,851246 Hall .e-. Maia-29, 1932 2,047,122 Brandenburger a.-. July 7 .1936 2,053,110 Regan. ..o Sept. 1, 1936 2,194,310 Leonard Mar. .19, 1940 2,236,298
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2625599A (en) * 1952-02-21 1953-01-13 William A Downes Apparatus and method for testing the accuracy of synchros
US2815409A (en) * 1955-12-30 1957-12-03 Gen Electric Intermittent time switch

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1490567A (en) * 1921-09-12 1924-04-15 William A Callahan Automatic traffic signal
US1851246A (en) * 1926-07-26 1932-03-29 Gen Electric Circuit controller
US2047122A (en) * 1931-02-14 1936-07-07 Crouse Hinds Co Program cycle timer
US2053110A (en) * 1932-10-21 1936-09-01 Gen Electric Signaling system and apparatus
US2194310A (en) * 1935-08-08 1940-03-19 Gen Electric Signaling system and apparatus
US2236298A (en) * 1938-04-23 1941-03-25 Gen Electric Traffic signal controller

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1490567A (en) * 1921-09-12 1924-04-15 William A Callahan Automatic traffic signal
US1851246A (en) * 1926-07-26 1932-03-29 Gen Electric Circuit controller
US2047122A (en) * 1931-02-14 1936-07-07 Crouse Hinds Co Program cycle timer
US2053110A (en) * 1932-10-21 1936-09-01 Gen Electric Signaling system and apparatus
US2194310A (en) * 1935-08-08 1940-03-19 Gen Electric Signaling system and apparatus
US2236298A (en) * 1938-04-23 1941-03-25 Gen Electric Traffic signal controller

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2625599A (en) * 1952-02-21 1953-01-13 William A Downes Apparatus and method for testing the accuracy of synchros
US2815409A (en) * 1955-12-30 1957-12-03 Gen Electric Intermittent time switch

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