US2817724A - Circuit controller in traffic control system - Google Patents

Description

Dec. 24, 1957 w. A. sKlDGEL 2,817,724

CIRCUIT CONTROLLER IN TRAFFIC CONTROL SYSTEM Filed Nov. 7, 1955 2 sheets-sheet 1 A75. J. @n

Dec. 24, 1957 w. A. sKlDGEL 2,817,724

CIRCUIT CONTROLLER IN TRAFFIC CONTROL SYSTEM Filed Nov. '7, 1955 2 Sheets-Sheet 2 CIRCUIT CONTROLLER IN TRAFFIC CONTROL SYSTEM yWilliam A. Skidgel, Ripon, Calif.

iApplicationvNovember-L 1955, Serial No. 545,255 3-Clain1s. (Cl. 200,-38)

` -Thepresent invention relatesto Yan improved .Circuit ffcQntrQlIeriQr use iny traflic control systems.

fMDIpeeic vraspects-of the present invention relate 4tof an,2 improvement Vin the timing arrangement shown and .elaimedzinmytapplication, Serial No.. 201,566, filed De- Gelnber ,2*19, .1950, fortrallic light control, now United States Letters-Patent2,7l9,283, patented September 27,

1955. The present` arrangement characteristically is provided; with: three .manually rotatable knobs rallowing more,

l,quicker convenient adjustment for purposes of con- QHDD lthe arhngement to, different traiiic conditions at the various ,intersections vat `which the portable traffic ',signalfis used. ,Further the present arrangement while, inegerleral, Similarin principleV to the arrangement shown in myabovementioned copending application involves allimprDVeCl-meehanieal assemblage of the circuit controlling, ellerrtents.,and` employs a .different circuitfor pro- .:ydgreinga fflashingfoperation .of the arrangement.

lAn-oibjeetof vthepresent invention is to provide an ,improved vtiming `circuit for a tratlic signal which is jeasilylandesimply .adiilstedto-provide dierent time `inft yalswhereinthedifferent red and green Vlights may b A,energizediorditerent selected periods of time.

l AnotherV object ofthepresent invention is to provide Ik improved timing apparatus of this character which `may be` easilyeonverted to provideilashing ot the yellow and red signals respectively along intersecting streets.

Another object ofthe presentinvention is to provide ,The features ofthe presentinvention which are `bevflieved ,toghey noye'lare set forthwith particularity in the i ,,appendedi claims. VThis invention itself, both vas to its y.Dri-a)ligation-and,manner of operation, together with rurther ,objectsand advantage-s thereof, may rbe .best un derstood byhrefelfence to the following description taken onneetionfvvith. the accompanying drawings in which:

`Eigtlreil isa.V view infront elevation kof la timing unit .@ernbodyingaffeatnres of the :present invention to which fhevariousotratie lights and battery are interconnected .iin asystem. as .shown in Figure 2. y .Eiguretis a circuit diagram illustrating the ,circuit-ry `iof'ttheotimingsunitr sho-wn in .Figure l as connected to deleted signal-flights -a-nd to an external storage batter-y.

."Figu-r-eS-is a view, mainly in elevation, as taken in :'lthefdirection indicated by the line 3-3 of Figure 4 and serves `to villustrate certa-in structure ofL the 'timing unit i'llustratedin Figure 1.

United States Patent Figure 4 is a view taken along the line 4-4 of Figure 3.

Figures 5 and 6 are views taken along corresponding lines 5 5 and 6 6 in Figure 4.

Figure 7 is a sectional view taken on the line 7.-7 of Figure 4.

Figure 8 is a sectional View taken lon the line l- .3 of Figure 4.

The system Shown in Figure 2 includes a traffic signal 10 vfor controlling the ilow of trame in the east-west direction, and a signal 11 for controlling simultaneously the tlow of traffic in a ,north-south direction. Each .Sgnal 10, 11 incorporates a red, yellow or amber, and green light represented respectively by the letters R, Y and G, R standing for red, Y standing for yellow, and G standing for green. Also, to facilitate reference to these diterent lights, they are given the reference numerals 10A, 10B, 10C and 11A, 11B and 11C.

A traffic signal which comprises in fact both signals 10 and 11, i. e., east-west and north-south tralic, produces signals of conventional character; that is, when the red light 10A` is illuminated either the green light 11C .or the yellow light 11B is illuminated; and, conversely, when the red light 11A is illuminated either the green light 10C or the yellow light 10B is illuminated. Further, the operation is such thatimmediately after deenergization of the red light 10A, ,the green light 10C is energized while in the transition from green to red, the yellow light 10B is energized for a brief time interval.

An alternate manner of operation is provided upon operation ot the three-position switch 13. When themovable switch contacts 13A, 13B engage the stationary eontacts 13C, 13D respectively, a bi-metallicfiasher 16 is periodically and automatically .energized to cause n simultaneous dashing of an opposite pair of yellow and red lights, i. e., yellow light 10B and red light 11A/or, in the alternative, yellow light 11B and red light 10A, depending upon the position of other switches deseribed in detail hereinafter.

Each one of the lights 10A, 10B and 10C .havey one of their terminals grounded while the other terminal of red light 10A is connected both to the stationary nswitch contact 17 on the so-called red switchl andto the movable .Contact 19 on the so-called greenfyellow switch 20 which has its two movable contacts 19 and `3 2 ganged by insulation 45 for operation in unison.

The ungrounded terminal of the yellow light 10B is connected to the yellow stationary switch contact 28; and the ungrounded terminal of the green light 10C is connected to the stationary switch contact 21 of the yellowgreen single-pole double-throw switch 22.

The red, yellow and green lights 11A, 11Band 11C each have one of their terminals grounded, while the other terminal of the red light 11A is connected both to the movable switch element 32 and to the stationary switch contact 30 of the red switch 18; the ungrounded terminal of the yellow light 11B is connected to the stationary yellow switch contact 25 of the switch 20; and the ungrounded terminal of the green light 11C is connected to the stationary green contact 26 of `the same switch 20.

The movable switch element 34 of the switch 18 is connected both to the movable switch contact 13A and to one terminal of the speed control rheostat 100. The movable contact lill of the rheostat is connected to one terminal of the direct current series connected motor 62, the other terminal of such motor 62 being connected to the stationary switch contact 13E.

It is observed that the terminals designated as 1, 2, 3, 4, 5, 6, 7 and 8 comprise contacts of a Jones type socket 103 (Figs. 2 and 1). Terminals 1 and 2 of such socket 103 are connected to opposite terminals of the storage batstares tery 40 which thus has its negative terminal grounded and its positive terminal connected, first, to one terminal of the thermall)r operated switch 16, and, second, to the stationary contact 105A of the relay 105; and, third, to the stationary switch contact 13F. Relay 105 includes the movable switch contact 165B and magnetizing winding 105C with the switch contact 105B being connected to the stationary contact 13C. One terminal of winding 105C is connected to one terminal of the flashing switch 16 while the other terminal of winding 105C is connected both to the movable switch contact 13B and to the heater terminal 16A of the thermally operated switch 16.

As indicated previously, the switch 13 is a three-position switch and, as shown in Figure 2, its movable switch elements 13A, 13B interconnected by insulation 107 for movement in unison is shown in its normally operating position wherein the switch elements 13A, 13B engage the contacts 13F and 13E respectively. This corresponds to the on position of switch 13 designated as such in Figure l. 1n the off position of switch 13 the switch elements 13A` and 13E do not engage any one of the stationary contacts 13C, 13D, 13E or 13F. However, in the Hash position of switch 13 the movable switch elements 13A, 13B engage the stationary contacts 13C and 13D. Now that the electrical circuit connections are described, it is necessary to have an understanding of the physical arrangements of the red switch 30 and greenyellow switch to fully appreciate the operation of the system. For that reason, a detailed description of the mechanical arrangement of the switches ensues prior to a description of the operation of the circuit.

Mechanical arrangement of red switch 18 and greenyellow switch 20, 22

These switches 18, Ztl, 22, illustrated in Figure 3, in relationship to the operating mechanism therefor illustrated in Figure 4, are operated cyclically in normal operation of the signaling system upon rotation of the shaft 73 which is driven at a reduced speed, through suitable gearing in the casing 74 by the aforementioned direct current series connected motor 62.

In general, the switches 20, 22 on the one hand and switch 34 on the other hand are operated by the adjustable multi-part cams 110 and 111 respectively. For that purpose as shown in Figures 3 and 6 a roller 112 mounted on the free end of a portion of the switch element 32 is constantly and resiliently pressed into engagement with the outer periphery of the two-part cam 110; likewise, as shown in Figures 3 and 5, a roller 120 is supported on the free end of a portion of the switch element 34 of resilient nature so that the cam roller 120 is at all times pressed into engagement with the adjustable outer periphery of the two-part cam 111.

The switches 2t), 22 and 34 as shown in Figure 3 are of conventional commercial structure and are snap-acting switches, and since the construction of these switches is well known, a specific description of the same need not be presented here.

Of importance however is the arrangement herein whereby the cam following rollers 112 and 120 are moved by the adjustable cams 110, 11.1., details of the construction of which are now described.

An important feature of the cams 110, 111 is that their contour or peripheral shape may be adjusted quickly and conveniently upon manual turning of the control knob 122 which, as indicated in Figure 1, allows adjustment, i. e., lengthening of the time during which a red light in one signal and the corresponding green light in the other signal is energized. In this respect it is observed that one complete cycle of operation is effected upon one complete rotation of the shaft 73. In other words, during one complete revolution of shaft 73 the signal 1t? (Figure 2) initially red during the initiation of the cycle becomes yellow, then green, and returns to red during such one revolution of shaft 73. This cycle may be shortened in time or lengthened by decreasing or increasing the rotational speed of the shaft 73. This is accomplished by adjustment of the speed of the series connected motor 62, i. e., by manually adjusting the tap 1111 (Fig. 2) `of the rheostat 160 (Figs. 2 and 4) using the so-called time knob 13G (Fig. 1) which is mounted on the rheostat shaft 131 (Fig. 4).

It should be understood that the contour or periphery of the cani 11) serves to determine that fractional part of the cycle during which the switches 20, 22 are in their actuated position shown in Figure 3.

The cam comprises in fact an inner libre ring 110A sandwiched by a pair of outer rings 110B and 110C. The inner ring 110A is slidably mounted on the shaft 135, such shaft being releasably secured to the output driving shaft 73 by set screw 136. The inner fibre ring 113A always turns with the shaft 135 since it has a noncircular central opening cooperating with a pair of ats 135A (Fig. 6) on the shaft 135. Such ats 135A of course allow movement of the disk 110A along the longitudinal axis of the shaft 135. The inner libre ring 111A of cam 111 is mounted on shaft 135 in the same manner as is the aforementioned described ring 110A so that such libre ring 111A always turns with the shaft 135 but cooperates with the flats 135A so that it is free to slide along the longitudinal axis of such shaft.

It is noted that the spaced inner fibre rings 110A and 111A each have a pair of aligned arcuate shaped apertured portions 110B and 111B therein so as to provide clearance for a pair of connecting shafts and 141 which extend and mount the outer bre rings 110B, 110C and 111B and 111C. These circular pins 140, 141 each have one of ther ends anchored in the ringshaped plate with the aforementioned outer rings 110B, 110C, and 111B and 111C slidably mounted on such pins 140, 141. This circular plate 150 is rotatably supported on one end of the shaft 135; different means for elfecting such rotational support may of course be provided and the one described specifically hereinafter is exemplary of those which may be used for that purpose. The circular plate 150 is centrally apertured to receive the shaft 151. Such shaft 151 has square or hexagonal portion 151A which cooperates with corresponding inner flat faces on the plate 150 whereby the circular plate 150 is rotated whenever the shaft 151 is rotated (see Figure 8).

This shaft 151 is rotatably supported in the bushing or bearing 160, which is fastened to the front plate 161 of the housing 162 (Figures 1 and 4) by means of the nut 163 threaded on such bushing 160 with lock washer means 164 interposed between the nut 163 and front plate 161. For purposes described in detail later, this bushing is provided with an enlarged annular ange 160A, which is spaced and extends parallel with the front plate 161 so as to provide a rotatable support for an adjustably positioned plate 165 mounting the switch 18.

The forward end of the shaft 151 mounts the control knob 122 while the rearwardly extending end of the shaft 151 has an integrally formed spindle 151B of reduced diameter which is free to rotate within the axially extending apertured portion 135B of the shaft 135. This spindle portion 151B is undercut and the inner wall of the apertured portion 135B is provided with a groove so as to receive the split locking ring 166 (Figures 4 and 7). Such split ring 166 allows rotational movement of the spindle 151B within the apertured portion 135B, but prevents relative axial movement between such members. It is understood that other means may be used to prevent such axial movement, but the one shown and described specilically herein is particularly desired since it facilitates an easy assembly, i. e., initially the split ring 166 is mounted on the spindle 151B and in assembling, the spindle 151B is shoved into the apertured portion 135B. In such case, when the resilient split ring 166 becomes aligned with the annular groove in such apertured por tion, the split ring 1,66 snaps outwardly to lock the spindle 'i151 against further *axial"mover-'nentd whileatthe lsame time allowing rotationaly movement of the spindle.

`yIt is clear that-the knob 1'22-may 'be `rotate`d^inde pendentlyY of the' shaft-1`3`5 and this 'mayt be" accomplished by'simply turning theknob 122'-inasmu'ch `as in lsuch instances the shaft-135' maybe' consideredto bel relatively 111A, 111B and 111C on the other hand. For imposing this friction the prestressed coil compression spring 170 is provided. The compression spring 170 has one of ite ends abutting the fiber plate 110C to press the outer fiber plate 110B against the enlarged shoulder on the shaft 135 while the other end of the spring 170 abuts the inner 'f fiber plate 111C to press the outer fiber disk 111B against the enlarged shoulder 151F on the shaft 151. By this means the composite cams 110, 111 serve not only as cams but also as frictional clutches for purposes of allowing the shaft 135 to rotate the knob 122 when of course such knob 122 is not engaged by the operator.

As described previously, the plate 165 is rotatably supported on the bushing 160 for pivotal movement about its central axis. This plate 165 is of sheet metal with a right angular bend therein to form the legs 165A and 165B. The leg 165A is circularly apertured and coniined between the bushing 160A and front plate 161 for providing the aforementioned rotatable support. The other leg 165B mounts the single-pole, double-throw snap acting switch 18 with the roller 120 always in constant engagement with the adjustable cam 111A. This bent plate 165 and the switch 18 (Figure 3) carried thereon may be rotated to different adjusted positions upon rotation of the so-called amber or yellow knob 175 (Figures 4 and 1). For this purpose the knob 175 is secured to a shaft 176 which extends through the front housing plate 161 and mounts the gear 177. Such gear 177 is in mesh, as shown in Figure 3, with the gear teeth 165B formed on the extension 165F of plate 165.

A recessed retaining ring 178 and the aforementioned gear 177 are on opposite sides of the plate 161 and are aflixed to the shaft 176, thus preventing axial movement of such shaft while allowing its rotation. In general, the switches 20, 22, considered as a pair, on the one hand and the switch 18 on the other hand are operated in that timed sequence described in my aforementioned patent application. In other words, while the construction herein allows substantially instantaneous operation of the switches 20, 22 upon rotation of the cam 110, the switch 18 is not operated instantaneously because of the relationship of the cams 110, 111. The switch 18 is actuated only after a predetermined time delay which is determined by the setting of the control knob 175.

It should be observed that the cams 110, 111 are adjusted in uni-son so that the relative shapes are predetermined and the manner in which such cams 110, 111 may be adjusted appears self-explanatory after the foregoing description. Briefly, after such cams 110, 111 are adjusted by grasping the control knob 122 and turning it manually while the shaft 135 is in a relatively stationary position due to the fact that either the motor 62 is energized or that sufficient resistance or inertia to turning of the shaft 135 is imposed by the reduction gear train in the casing 74. Under this condition the turning of the knob 122 results in turning the plate 150 and the pins 140 and 141, which are anchored thereto. This movement of the pins 141 results in movement of the outer fiber plates 110B, 110C and 111B, 111C since the same are slidably mounted on such pins 140, 141. However, the

`linner" ber` pla-tes y110A *arid l'1111A are v-not'f'mmled T'since f such :pins i140, ``141ipassf 'through clearance openings *in the same-sway asillustrate'd 'inlFigures l5=a\'!id6. lFor'f effcc-'tin g such s relative movement fof -the )adjustable f cams `110,' 111 Lbetween'theiinner andfouter ffiber k`rli'sl-'.s,""the prestressed coil compression spring 170 zis made-suf- A`ticientlyfweak. `Info'ther- 'wor-ds; thespring l 170" lis sufficien-tlyweak' to-allowrlative movementtbet-ween thefber disks -when thev ycontrol'-'lcrlob 122-1 is-grasped V'and rotated manually 4whileatI 'the same `time-the springJ 170 is suiei- -ently strong-torcauseall 'off'the fiberffdisksf to -rnoveqas a unit when the motor 62 is energized and-of coursethe operator` no longer grasps-I thei knob 122.

@With theswit'ches1-8,f20and 22 intheir-*positionsshown position as shown in Figure 2, it is clear that the red light 10A in the east-west signal 10 is energized. Simultaneously the green light 11C inthe north-south signal is energized. Thereafter, when and as the shaft 135 is rotated, the cams 110, 111 of course are rotated initially to cause the switch element 19 to engage the contact 25 and to cause the switch element 32 to engage the switch element 21, not effecting energization of the red light 10A, but causing de-energization of the green light 11C, and substantially simultaneously energization of the yellow light 11B. The further rotational movement of the shaft 13S does not effect operation of the switches 20, 22, but results in movement of the switch element 34 into engagement with the contact 30, thereby producing energization of the red light 11A and simultaneous energization of the green light 10C. The time interval during which the yellow light 11B is illuminated may be adjusted by adjusting the position of the aforementioned knob 175. When the last mentioned condition exists, i. e., when the red light 11A and green light 10C are illuminated, the cam roller 112 is in engagement with the lowest circumferential point on the cam 110. In this respect it is observed that the cam in Figure 6 has effective one lobe, that is, a position of the cam 110 diametrically opposed to the lobe is defined substantially by a semicircle. For that reason the cam 110 is referred to as a single-lobe semicircular cam.

It may be demonstrated that upon continued movement of the shaft from the aforementioned position wherein the switch contacts 19 and 25 are in engagement, similar operation of the signals 10 and 11 are effected.

When it is desired to produce a flashing red signal in the north-south direction and, simultaneously, a iiashing yellow light in the east-west direction, the switch 13 is positioned with the contacts 13A, 13B in engagement with the contacts 13 or 13D. In such case bimetallic element 16 is automatically periodically heated and caused to interrupt in turn the current to the relay winding 105C, with the result that a recurrently interrupted current ows through the lights 11A and 10B. In such flashing operation, of course the motor 62 is de-energized.

While the particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from this invention in its broader aspects and, therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of this invention.

I claim:

1. A circuit controller for use in a signaling system of the character described, a first shaft, a second shaft, means rotatably supporting said second shaft for rotation on said first shaft and about the same axis as said first shaft while preventing relatively longitudinal movement of both of said shafts, abutment means on said first shaft, abutment means on said second shaft, a pair of pins mounted on one of said abutment means and extending parallel with the axis of each of said shafts, a pair of adjustable cams each comprising a pair of disks slidably mounted on said pins sandwiching an intermediate disk having an arcuate clearance opening through which said pins extend, and a prestressed coil compression spring having opposite ends thereof engaging opposite ones of said cams for pressing the same into engagement with corresponding ones of said abutment means.

2. The arrangement set forth in claim 1 in which switch means are stationarily mounted adjacent one of said cams, a second switching means is mounted adjacent the other cam for actuation thereby, and means adjustably support* ing one of said switch means with respect to its corresponding cam.

3. The arrangement set forth in claim 2 in which a motor is geared to said first shaft, and a manually operable knob is mounted on said second shaft, said spring means being sufficiently strong to develop `suicient friction between said disks to effect driving of said second shaft by said first shaft, but being sufficiently weak to allow turning of said second shaft with respect to said rst shaft to thereby adjust the position of the inner sandwiched disks with respect to the associated outer disks to thereby change the contour of both earns simultaneously.

References Cited in the le of this patent UNITED STATES PATENTS 1,851,246 Hall Mar. 29, 1932 1,851,247 Hall Mar. 29, 1932 2,324,051 Allen July 13, 1943 2,719,283 Skidgel Sept. 27, 1955

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