Communications: electrical – Vehicle detectors – With camera
Patent
1987-06-08
1989-11-28
Orsino, Joseph A.
Communications: electrical
Vehicle detectors
With camera
346107VP, G01D 300
Patent
active
048840726
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The invention relates to a device for photographic monitoring of a road intersection controlled by means of a traffic light installation, comprising:
(a) a photographic camera covering the road intersection,
(b) a first sensor, which responds to a vehicle entering the road intersection beyond a first position, and supplies a sensor signal,
(b) means for producing a stop interval signal in response to the change-over of the traffic light installation to a stop interval,
(d) a camera-triggering device, which is arranged to be energized by trigger signals to trigger exposures of the photographic camera,
(e) signal processing means to which the sensor signal and the stop interval signal are applied, and which are arranged to produce a first triggering signal for triggering a first exposure of the camera when a sensor signal appears during the duration of the stop interval signal,
(f) means for producing a second triggering signal with delay with respect to the first triggering signal to trigger a second exposure,
(g) and a second sensor.
BACKGROUND ART
It is known to monitor road intersections controlled by traffic lights. To this end a sensor is arranged on the lane in the range of the traffic light, which sensor supplies a sensor signal when a vehicle passes over it. If such a signal appears during the stop interval of the traffic light, that is if a vehicle enters the road intersection during the stop interval contrary to traffic regulations, a photographic camera will be triggered, the field of view of which covers the road intersection controlled by traffic lights. Thereby a photograph is taken of the traffic violation and also of the license plate of the vehicle in question (DE-A- 683,658).
It is also known to trigger by the sensor signal successively several photographic exposures in adjustable time intervals, if a sensor arrangement establishes a traffic violation of a vehicle. This traffic violation may consist in that the vehicle enters a road intersection during the stop interval. Then the photographic camera is triggered by a signal when passing a contact sensor embedded in the lane. The traffic violation may also consist in that the vehicle runs too fast. In this case the photographic camera is triggered by two contact thresholds embedded one behind the other at a fixed distance in the lane, being passed within a predetermined time interval corresponding to the speed limit (DE-A- 10 78 797 or AT-A- 225,077). The two contact sensors embedded one behind the other in driving direction exclusively serve for the speed measurement.
By DE-C- 2,365,331 a device is known for photographic monitoring of road intersections controlled by traffic lights, which device has a photographic camera covering the road intersection and a sensor responding to a vehicle entering the road intersection, and supplies a sensor signal by means of a detector circuit. A camera-triggering device is aranged to be energized by a first triggering signal triggered by the sensor signal through a first gate circuit for triggering a first exposure. The first gate circuit is arranged to be rendered conductive by a signal from the traffic light during its stop interval. When the first exposure is triggered, a time function element is triggered and changes its state for a predetermined delay time. After expiration of the delay time, a second triggering signal applied to the camera-triggering device for triggering an exposure is produced by the time function element. The first gate circuit is then non-conductive from the triggering of the first exposure to the end of the second exposure. In this manner a second vehicle entering the road intersection shortly after the first triggering vehicle cannot directly cause a triggering signal directly, before the cycle consisting in the first and the second exposures initiated by the first vehicle is finished. The sensor signal is, however, simultaneously applied to a second gate circuit which is rendered conductive during the non-conductive period of the first gate circuit. The o
REFERENCES:
patent: 2871088 (1959-01-01), Abell
patent: 3060434 (1962-10-01), Biedermann et al.
patent: 3858223 (1974-12-01), Holzapfel
patent: 3866165 (1975-02-01), Maronde et al.
Machine Design, Band 38, Nr. 2, "Camera Gets Black and White Evidence Against Speeding Motorist" Jan. 1966.
Orsino Joseph A.
Tumm Brian R.
LandOfFree
Device for photographic monitoring of cross-roads does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Device for photographic monitoring of cross-roads, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Device for photographic monitoring of cross-roads will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-584909