US3196386A - Automatic traffic regulating system for street intersections - Google Patents
Automatic traffic regulating system for street intersections Download PDFInfo
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- US3196386A US3196386A US90501A US9050161A US3196386A US 3196386 A US3196386 A US 3196386A US 90501 A US90501 A US 90501A US 9050161 A US9050161 A US 9050161A US 3196386 A US3196386 A US 3196386A
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- intersection
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- trafiic
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- street
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- G—PHYSICS
- G08—SIGNALLING
- G08G—TRAFFIC CONTROL SYSTEMS
- G08G1/00—Traffic control systems for road vehicles
- G08G1/07—Controlling traffic signals
- G08G1/08—Controlling traffic signals according to detected number or speed of vehicles
Definitions
- the present invention has as its object an automatic traffic regulating system of the type whose signals are subject to control by the traffic at road intersections, at blind curves whereby vehicles crossing the intersection are warned to stop or slow down and thereby prevent accidents and at stop signs.
- the automatic traffic regulating system of the invention comprises, in combination, vehicle-activated signaling means along each of the streets of the intersection for closing one ormore electrical circuits by passage of the vehicle over said means along the street route, an electronic switching mechanism capable upon interruption by vehicular traffic of the vehicle actuated signaling means to energize the circuits and operate one or more visible signals and the visible signaling means which indicate to the driver whether the route is free from vehicular traffic, along a direction which the driver cannot perceive, thereby providing the necessary trafiic inl formation to the driver to enable him to proceed with complete safety.
- the automatic traffic regulating and signaling system of the invention provides sufiicient and timely warning to vehicular trafiic of intersection, main highway, dangerous, curve and road under construction ahead and avoids serious collision with faster moving main highway traffic for vehicles turning into or crossing main highways from a side street, and for vehicles coming into hidden curves and unseen road construction.
- the visible signaling system is actuated by but a single vehicle.
- Another advantage of the automatic signaling system of the invention is the assurance that a vehicle coming in any direction into thedangerous area on the highway will positively actuate the visible signaling system to provide warning to oncoming trafiic from a different direction.
- FIG. 1 shows a perspective view in diagrammatic form of the visible signaling means employed in the invention.
- FIG. 2 shows a plan view in diagrammatic form, the placement of the signaling means of FIG. 1 at a through intersection.
- the signal lighting device of the invention Upon approaching the intersection and mechanically actuating the speed contact the signal lighting device of the invention is adapted to locate on the hanging box 5 the position of the car which has approached the light along the cross route. A specific illustration will be seen,
- the novel signaling device provides an extension for the view ofthe driver of each vehicle approaching the intersection to cover areas of approach ordinarily locked from his view.
- the lighting color' system used for this traffic identification function of the novel signaling device can be varied to suit local and national highway standards and regulations.
- the approach of vehicles on secondary roads will actuate the warning signal and the color of red, amber, orange or yellow might be used on the main highway as well as on the secondary'highway to permit an effective warning within the experience under local highway regulations.
- the automatic trafiic regulating system of the present invention will operate on any one of the treadles 1, 2, 3 and 4 in the locations which are shown at the street intersection. It is only for treadle 4 that the diagrammatic circuit comprising the time delay means and the light switch control is shown in the drawing. The time delay and light switch control is also present for each of treadles 1,2 and 3 and the operation is essentially the same.
- a car approaching the traflic signal atthe intersection depresses treadle 4.
- Light 4' which is the center light in the set facing the treadle approached and actuated by the car, is a green light and as a result of the actuation of the light control switch diagrammatically shown, lights 4' and 4' are illuminated as red lights.
- treadle 4 As a result of the actuation of treadle 4, the cars on the cross street are warned by the illumination of the red lights 4" and 4 that a car is approaching from the direction of treadle 4.
- the location of illuminated red light 4" warns a car approaching the signal box on the cross street from the direction of treadle 1 that a car in cross trafiic approaches from the right.
- the location of illuminated red light 4" at the left of the box when viewed by a driver approaching the main highway from the direction of treadle 3, conveys to this driver 3 the information that the car which approaches and illuminated the box is now approaching from the left.
- the distance of setback of street contacts 1, 2, 3 or 4 from the intersection varies in accordance with the average rate of speed or speed limit control for main and secondary highways.
- the street contacts 1, 2, 3 and 4 are a preferred example of vehicle actuated signaling means. It is preferred that the invention use a treadle of the mechanical type because of its simplicity, easy construction, easy maintenance and economy.
- the, signaling is automatic and can be controlled for time delay upon actuation of the vehicle actuated means on the street remote from the highway intersection.
- the circuitry means used to post by traffic light signal- ,ing both position and direction at anintersection ,or at a curve for all cars coming in every direction differs from conventional circuitry by being directly connected to a position light on the traffic signaling means.
- the box device 5 used in the array of lights shown in FIGS. 1 and 2 the box device comprises a light for driversposition', two lights for approaching vehicles position from both directions of cross traffic at the intersection.
- the car coming in cross traflic from the right makes a visible signal in the array of three lights at the right side and a car coming from the left makes a visible signal at the left side of the array of three lights.
- Each of the four sides are arranged with these three lights operating in identical sense. Thereby each vehicle upon approaching the intersection posts its central light and is warned by specific location of lights, right or left, actuated by vehicles in the same relative positions, right or left, when crossing the intersection.
- time delay devices of the conventional types, and a specific illustration of a cutolf device may employ a motor in the circuit diagram shown in FIG. 2 of U.S. Patent to Neill, No. 2,015,435, this motor operating by reverse rotation and being actuated by a second detector.
- a more complex electronic timing circuit of the type described in Barker, U.S. Patent No. 2,883,644 may be employed.
- any cutoff mechanism can be used and the details of the cutoff mechanism whether of the motor type as in Neill or the electronic type in Barker are not part of the present invention, these details being known in the art. It is 4 obviously preferred to use simpler mechanisms of the known motor or clock type.
- the new operation of the system of the invention comprises a specific type of self-posting actuation by the first vehicle approaching to register the operation of the trafiic signaling means by lighting a light of smaller aperture therein, this first lighting indicating posting of the approaching vehicle simultaneously registering oneor more lights of larger aperture in the signaling device facing the cross direction whereby approaching cross traffic is immediately warned by the first vehicle, the warning made more effective by the largeraperture and the location being simultaneously registered to the second or later approaching vehicle or vehicles by locating the larger lighting aperture for cross trafiic on the same side as that from which the first vehicle approaches the intersection or curve.
- a traffic signal in'the form of a box furnished with three lights on each side of the box, each side facing a street of the intersection; said box being placed overhead at the intersection to be visible approaching the intersection from all directions; said three lights on each side of the box consisting of a center light and two outer lights, said center light indicating free passage and being smaller in diameter than said outer lights, while said outer lights warn the approach of cross trafiic; light switching means connecting to and lying between each of said treadles and said box'signal which are energized by the move nient of thevehicle over the treadle as the vehicle approaches the intersection, and time delay means connected to'said light switching means, said delay means maintaining the trafiic signal in lit condition for a predetermined time after actuation, the larger lights
Description
July 26, 1965 3. R088] ETAL 3,196,386
AUTOMATIC TRAFFIC REGULATING SYSTEM FOR STREET INTERSECTIONS Filed Feb. 20. 1961 FIG. 2.
3 j jm k 3 ME Light Control CUT OFF 4 Q DELAY INVENTORS Bruno Rossi Cami/Io Calderoni mm a 4;
ATTORNEY United States Patent 3,196,386 AUTOMATIC TRAFFHC REGULATENG SYSTEM FOR STREET INTERSEQTEGNS Bruno Rossi and Camilla Calderoni, both of Via Indipendenza 58, Bologna, Italy Filed Feb. 20, 1961, Ser. No. 0,501 1 Claim. ((31. 349-31) The present invention has as its object an automatic traffic regulating system of the type whose signals are subject to control by the traffic at road intersections, at blind curves whereby vehicles crossing the intersection are warned to stop or slow down and thereby prevent accidents and at stop signs.
The automatic traffic regulating system of the invention comprises, in combination, vehicle-activated signaling means along each of the streets of the intersection for closing one ormore electrical circuits by passage of the vehicle over said means along the street route, an electronic switching mechanism capable upon interruption by vehicular traffic of the vehicle actuated signaling means to energize the circuits and operate one or more visible signals and the visible signaling means which indicate to the driver whether the route is free from vehicular traffic, along a direction which the driver cannot perceive, thereby providing the necessary trafiic inl formation to the driver to enable him to proceed with complete safety.
The automatic traffic regulating and signaling system of the invention provides sufiicient and timely warning to vehicular trafiic of intersection, main highway, dangerous, curve and road under construction ahead and avoids serious collision with faster moving main highway traffic for vehicles turning into or crossing main highways from a side street, and for vehicles coming into hidden curves and unseen road construction.
It is an important characteristic of the traffic signaling system of the invention that the visible signaling system is actuated by but a single vehicle.
Another advantage of the automatic signaling system of the invention is the assurance that a vehicle coming in any direction into thedangerous area on the highway will positively actuate the visible signaling system to provide warning to oncoming trafiic from a different direction.
The foregoing objects and advantages of the invention will be better understood by referring to the accompanying drawings which are for the purpose of illustrating preferred embodiments of the invention and are not intended to limit the scope or spirit of the invention, since many changes in form and detail lying within the scope of the invention defined in the claim will be apparent to those skilled in the art.
In the drawings,
FIG. 1 shows a perspective view in diagrammatic form of the visible signaling means employed in the invention; and
FIG. 2 shows a plan view in diagrammatic form, the placement of the signaling means of FIG. 1 at a through intersection.
The circuitry in the boxes shown in FIG. 2 including relays and timing elements which are ordinarily used are as disclosed in the United States Patent to Horni, No. 2,049,651. However, these details of Horni do not form any part of the present invention, being known to the art and the invention differs in the manner in which the lighting device of FIG. 1 herein is operated.
Upon approaching the intersection and mechanically actuating the speed contact the signal lighting device of the invention is adapted to locate on the hanging box 5 the position of the car which has approached the light along the cross route. A specific illustration will be seen,
3,195,385 Patented July 20, 1965 ice from bottom to top on the main highway shown in the vertical direction. The contact 4' actuates signal light 4 green) and this in turn provides an actuation of signal lights 4" and 4" in box 5. These locations of actuation on the box provide complete information to a vehicle which approaches on the secondary highway traveling in the counter direction, diagrammatically downwardly or upwardly on the secondary road or a vehicle traveling in the opposite direction on the main road.
Accordingly, it is seen that for each of the street contacts 1, 2, 3 and 4 which are actuated by vehicles approaching the intersection from the four directions to the intersection, there is a signal flashing to locate the position of each vehicle and to inform the driver of each vehicle concerning the position of every other vehicle approaching the intersection. In effect, the novel signaling device provides an extension for the view ofthe driver of each vehicle approaching the intersection to cover areas of approach ordinarily locked from his view.
It can readily be understood that the lighting color' system used for this traffic identification function of the novel signaling device can be varied to suit local and national highway standards and regulations. For example, the approach of vehicles on secondary roads will actuate the warning signal and the color of red, amber, orange or yellow might be used on the main highway as well as on the secondary'highway to permit an effective warning within the experience under local highway regulations. 1
The circuit which 'is actuated by the closing of the street contact to provide the illuminated signal warning differs from the circuit which is employed in patent to Horni, U.S. No. 2,049,651. 1
As shown in FIG. 2,- the automatic trafiic regulating system of the present inventionwill operate on any one of the treadles 1, 2, 3 and 4 in the locations which are shown at the street intersection. It is only for treadle 4 that the diagrammatic circuit comprising the time delay means and the light switch control is shown in the drawing. The time delay and light switch control is also present for each of treadles 1,2 and 3 and the operation is essentially the same. A car approaching the traflic signal atthe intersection depresses treadle 4. Light 4', which is the center light in the set facing the treadle approached and actuated by the car, is a green light and as a result of the actuation of the light control switch diagrammatically shown, lights 4' and 4' are illuminated as red lights.
In the combination of electric lamps in the trafiic signal box represented by the series of lights 4, 4 and 4", the illustrative case of FIG. 2 assumes that trafiic in the transverse direction on the highway between treadles 1 and 3 represents the stream of trafiic on the cross street, while the trafiic at right angles thereto between treadles 4 and 2. represents trafiic on the main highway. The car under consideration is approaching the intersection after passing over treadle 4.
As a result of the actuation of treadle 4, the cars on the cross street are warned by the illumination of the red lights 4" and 4 that a car is approaching from the direction of treadle 4.
In the embodiment of FIG. 2, the location of illuminated red light 4" warns a car approaching the signal box on the cross street from the direction of treadle 1 that a car in cross trafiic approaches from the right. The location of illuminated red light 4" at the left of the box, when viewed by a driver approaching the main highway from the direction of treadle 3, conveys to this driver 3 the information that the car which approaches and illuminated the box is now approaching from the left.
The distance of setback of street contacts 1, 2, 3 or 4 from the intersection varies in accordance with the average rate of speed or speed limit control for main and secondary highways.
The street contacts 1, 2, 3 and 4 are a preferred example of vehicle actuated signaling means. It is preferred that the invention use a treadle of the mechanical type because of its simplicity, easy construction, easy maintenance and economy.
From the foregoing explanation, it will be seen that the, signaling is automatic and can be controlled for time delay upon actuation of the vehicle actuated means on the street remote from the highway intersection.
From the foregoing detailed description of the preferred embodiments of visible signaling box device 5 in 7 FIGS. 1 and 2 for trafiic control at intersections, it is seen that the novel arrangement of the invention differs from those conventionally used in that each traveling vehicle, regardless of direction, actuates the traffic actuated signaling means for all traffic locations with the requirement that such actuation will, by closing a conventional type of light switch and time delay circuit, cause the lighting of .twosignals along the cross line of trafiic which'is' transverse to the line in which the vehicle is being driven and a third signal in the main direction to indicate that the signal is operating these signals being arranged geometrically to locate the true position -on the cross-highway of the car which actuates the vehicle signaling means and thereby providing warnings in both directions on the main line of traffic and, at the same time, giving a warning in the one transverse direction to the right or left of the signaling vehicle'at' the intersection.
The circuitry means used to post by traffic light signal- ,ing both position and direction at anintersection ,or at a curve for all cars coming in every direction differs from conventional circuitry by being directly connected to a position light on the traffic signaling means. At the center of the box device 5 used in the array of lights shown in FIGS. 1 and 2, the box device comprises a light for driversposition', two lights for approaching vehicles position from both directions of cross traffic at the intersection. The car coming in cross traflic from the right makes a visible signal in the array of three lights at the right side and a car coming from the left makes a visible signal at the left side of the array of three lights. Each of the four sides are arranged with these three lights operating in identical sense. Thereby each vehicle upon approaching the intersection posts its central light and is warned by specific location of lights, right or left, actuated by vehicles in the same relative positions, right or left, when crossing the intersection.
It is a critical feature of the invention that the automatic operation of the trafiic signaling meansemploys means for cutting off the trafiic signal means after the vehicles have gone beyond the traflic signal. For this purpose, there may be used time delay devices of the conventional types, and a specific illustration of a cutolf device may employ a motor in the circuit diagram shown in FIG. 2 of U.S. Patent to Neill, No. 2,015,435, this motor operating by reverse rotation and being actuated by a second detector. Or if desired, a more complex electronic timing circuit of the type described in Barker, U.S. Patent No. 2,883,644 may be employed. Any cutoff mechanism can be used and the details of the cutoff mechanism whether of the motor type as in Neill or the electronic type in Barker are not part of the present invention, these details being known in the art. It is 4 obviously preferred to use simpler mechanisms of the known motor or clock type.
It will therefore be seen that the new operation of the system of the invention comprises a specific type of self-posting actuation by the first vehicle approaching to register the operation of the trafiic signaling means by lighting a light of smaller aperture therein, this first lighting indicating posting of the approaching vehicle simultaneously registering oneor more lights of larger aperture in the signaling device facing the cross direction whereby approaching cross traffic is immediately warned by the first vehicle, the warning made more effective by the largeraperture and the location being simultaneously registered to the second or later approaching vehicle or vehicles by locating the larger lighting aperture for cross trafiic on the same side as that from which the first vehicle approaches the intersection or curve. On all sides, at curve or intersection, all vehicles are warned of approach and location of all crossing vehicles which eluding a single element treadle occupying only one-half the width of the road located along each of the streets of the intersection for lighting a trafiic signal; a traffic signal in'the form of a box furnished with three lights on each side of the box, each side facing a street of the intersection; said box being placed overhead at the intersection to be visible approaching the intersection from all directions; said three lights on each side of the box consisting of a center light and two outer lights, said center light indicating free passage and being smaller in diameter than said outer lights, while said outer lights warn the approach of cross trafiic; light switching means connecting to and lying between each of said treadles and said box'signal which are energized by the move nient of thevehicle over the treadle as the vehicle approaches the intersection, and time delay means connected to'said light switching means, said delay means maintaining the trafiic signal in lit condition for a predetermined time after actuation, the larger lights which are lit on the side of the box representing the side of the street from which the vehicle approaches and the larger "outer light being simultaneously lit on the opposite side of the box as a warning light to provide warning on each of the sides of the box facing the cross trafiic, and to a later vehicle in cross traffic that an earlier vehicle was passing through the intersection.
References Cited by the Examiner UNITED STATES PATENTS 7 NEIL C. READ, Primary Examiner.
THOMAS B. HABECKER, RUDOLPH V. ROLINEC,
Examiners.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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US90501A US3196386A (en) | 1960-07-23 | 1961-02-20 | Automatic traffic regulating system for street intersections |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
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GB2571260A GB925452A (en) | 1960-07-23 | 1960-07-23 | Improvements in or relating to road-way signalling systems |
US90501A US3196386A (en) | 1960-07-23 | 1961-02-20 | Automatic traffic regulating system for street intersections |
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US3196386A true US3196386A (en) | 1965-07-20 |
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US90501A Expired - Lifetime US3196386A (en) | 1960-07-23 | 1961-02-20 | Automatic traffic regulating system for street intersections |
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Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6005491A (en) * | 1999-01-07 | 1999-12-21 | Kopchak; James | Motion detecting traffic light |
US6188329B1 (en) | 1998-11-23 | 2001-02-13 | Nestor, Inc. | Integrated traffic light violation citation generation and court date scheduling system |
US6754663B1 (en) | 1998-11-23 | 2004-06-22 | Nestor, Inc. | Video-file based citation generation system for traffic light violations |
US6760061B1 (en) | 1997-04-14 | 2004-07-06 | Nestor Traffic Systems, Inc. | Traffic sensor |
US20050040970A1 (en) * | 2001-10-19 | 2005-02-24 | Hutchins J. Marc | Informational system using lighted message arrays for providing direction and guidance traffic ways |
US20050046597A1 (en) * | 2003-08-18 | 2005-03-03 | Hutchison Michael C. | Traffic light signal system using radar-based target detection and tracking |
US20110221614A1 (en) * | 2010-03-11 | 2011-09-15 | Khaled Jafar Al-Hasan | Traffic Control System |
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GB221328A (en) * | 1923-08-07 | 1924-09-11 | William Austin | Improvements in or relating to traffic-signalling systems |
GB266016A (en) * | 1925-10-13 | 1927-02-14 | Thomas Barker Ross | Improvements in road signalling devices |
US1662348A (en) * | 1925-09-12 | 1928-03-13 | George W Stricker | Changeable sign and traffic signal |
US2119593A (en) * | 1936-04-20 | 1938-06-07 | George W Gates | Traffic signal system |
US2203871A (en) * | 1936-10-13 | 1940-06-11 | Rca Corp | Radio traffic control |
US2371909A (en) * | 1939-12-01 | 1945-03-20 | Naerbo Daniel | Fluid operated switch |
US2829362A (en) * | 1954-05-03 | 1958-04-01 | Terrill Frank | Traffic control system |
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1961
- 1961-02-20 US US90501A patent/US3196386A/en not_active Expired - Lifetime
Patent Citations (7)
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GB221328A (en) * | 1923-08-07 | 1924-09-11 | William Austin | Improvements in or relating to traffic-signalling systems |
US1662348A (en) * | 1925-09-12 | 1928-03-13 | George W Stricker | Changeable sign and traffic signal |
GB266016A (en) * | 1925-10-13 | 1927-02-14 | Thomas Barker Ross | Improvements in road signalling devices |
US2119593A (en) * | 1936-04-20 | 1938-06-07 | George W Gates | Traffic signal system |
US2203871A (en) * | 1936-10-13 | 1940-06-11 | Rca Corp | Radio traffic control |
US2371909A (en) * | 1939-12-01 | 1945-03-20 | Naerbo Daniel | Fluid operated switch |
US2829362A (en) * | 1954-05-03 | 1958-04-01 | Terrill Frank | Traffic control system |
Cited By (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6760061B1 (en) | 1997-04-14 | 2004-07-06 | Nestor Traffic Systems, Inc. | Traffic sensor |
US6754663B1 (en) | 1998-11-23 | 2004-06-22 | Nestor, Inc. | Video-file based citation generation system for traffic light violations |
US6281808B1 (en) | 1998-11-23 | 2001-08-28 | Nestor, Inc. | Traffic light collision avoidance system |
US6573929B1 (en) * | 1998-11-23 | 2003-06-03 | Nestor, Inc. | Traffic light violation prediction and recording system |
US6647361B1 (en) | 1998-11-23 | 2003-11-11 | Nestor, Inc. | Non-violation event filtering for a traffic light violation detection system |
US20040054513A1 (en) * | 1998-11-23 | 2004-03-18 | Nestor, Inc. | Traffic violation detection at an intersection employing a virtual violation line |
US6188329B1 (en) | 1998-11-23 | 2001-02-13 | Nestor, Inc. | Integrated traffic light violation citation generation and court date scheduling system |
US6950789B2 (en) | 1998-11-23 | 2005-09-27 | Nestor, Inc. | Traffic violation detection at an intersection employing a virtual violation line |
US6005491A (en) * | 1999-01-07 | 1999-12-21 | Kopchak; James | Motion detecting traffic light |
US20050040970A1 (en) * | 2001-10-19 | 2005-02-24 | Hutchins J. Marc | Informational system using lighted message arrays for providing direction and guidance traffic ways |
US20050046597A1 (en) * | 2003-08-18 | 2005-03-03 | Hutchison Michael C. | Traffic light signal system using radar-based target detection and tracking |
US7821422B2 (en) | 2003-08-18 | 2010-10-26 | Light Vision Systems, Inc. | Traffic light signal system using radar-based target detection and tracking |
US20110221614A1 (en) * | 2010-03-11 | 2011-09-15 | Khaled Jafar Al-Hasan | Traffic Control System |
US8395530B2 (en) * | 2010-03-11 | 2013-03-12 | Khaled Jafar Al-Hasan | Traffic control system |
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