TRAFFIC FLOW DETECTING APPARATUS

• US 3,573,724 A
• Filed: 07/10/1967
• Issued: 04/06/1971
• Est. Priority Date: 07/15/1966
• Status: Expired due to Term

• Current Assignee: Komorida Katsuhiro
• Original Assignee: Komorida Katsuhiro
• Inventors: KOMORIDA KATSUHIRO
• Application Number:
  US04/652,158
• Time in Patent Office: 1,366 Days
• US Class Current: 340/934
• CPC Class Codes: G08G 1/01 Detecting movement of traffic to be counted or controlled G08G1/07 - G08G1/14 take precedence

Abstract

A traffic flow detecting apparatus in which a noise delivered from a running vehicle is utilized to derive an information for the signal control of an actuation-responsive traffic signal device. The traffic flow detecting apparatus is more economical and practical than the treadle type, inductance loop coil type and radar type.

Claims

1. An average traffic flow detecting apparatus comprising, in combination, noise detector means placed adjacent a road, noise level meter means connected to said noise detector means, a level discriminator means for comparing an output level of said noise level meter means with a reference level, and averaging means connected to the output of said level discriminator means for providing a signal representing an average traffic by determining a time-based mean value of the output of said level discriminator means.

2. An average traffic flow detecting apparatus as defined in claim 1, wherein said level discriminator means includes means for comparing an input thereof with a reference level and quantizing the same into two values.

3. An average traffic flow detecting apparatus as defined in claim 1, wherein said level discriminator means is a saturation amplifier.

4. A traffic flow detecting apparatus comprising, in combination, a pair of noise detectors placed at roadsides adjacent mutually opposed traffic lanes, a comparator means for mutually comparing the outputs of said pair of noise detectors, a level discriminator means connected to each of said noise detectors and to said comparator means for discriminating an output level of said detector with a reference level, said discriminator means being controlled acCording to the output of said comparator means, and an averaging means connected to each of said level discriminator means for providing a time-based mean of the output of said discriminator means, so that the informations of the inbound and outbound traffic flows are separately obtained.

5. A traffic flow detecting apparatus comprising, in combination a pair of noise detectors placed at roadsides adjacent mutually opposed traffic lanes, a plurality of filter means connected to the output of each noise detector for dividing the output into the same number of frequency ranges, comparator means connected to said filter means for mutually comparing corresponding frequency components of the outputs of said pair of noise detectors, gate means connected to each noise detector and said comparators for controlling the transmission of the output signal of said noise detector according to the output of said comparators, and an averaging means connected to each of said level discriminator means for providing a time-based mean of the output of said discriminator mean, so that the informations of the inbound and outbound traffic flows are separately obtained.