GB1066475A - Improvements in or relating to road traffic detecting arrangements - Google Patents

Improvements in or relating to road traffic detecting arrangements

Info

Publication number
GB1066475A
GB1066475A GB2357264A GB2357264A GB1066475A GB 1066475 A GB1066475 A GB 1066475A GB 2357264 A GB2357264 A GB 2357264A GB 2357264 A GB2357264 A GB 2357264A GB 1066475 A GB1066475 A GB 1066475A
Authority
GB
United Kingdom
Prior art keywords
loops
vehicle
diodes
phase
loop
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB2357264A
Inventor
Eric Parker
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Decca Ltd
Original Assignee
Decca Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Decca Ltd filed Critical Decca Ltd
Priority to GB2357264A priority Critical patent/GB1066475A/en
Publication of GB1066475A publication Critical patent/GB1066475A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P11/00—Measuring average value of speed
    • G01P11/02—Measuring average speed of number of bodies, e.g. of vehicles for traffic control
    • G—PHYSICS
    • G08—SIGNALLING
    • G08G—TRAFFIC CONTROL SYSTEMS
    • G08G1/00—Traffic control systems for road vehicles
    • G08G1/01—Detecting movement of traffic to be counted or controlled
    • G08G1/042—Detecting movement of traffic to be counted or controlled using inductive or magnetic detectors

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Position Fixing By Use Of Radio Waves (AREA)

Abstract

1,066,475. Road traffic detectors. DECCA Ltd. Sept. 8, 1965 [June 8, 1964], No. 23572/64. Heading G4Q. In a vehicle detecting system employing a plurality of inductive loops in close proximity each fed with alternating current, improper operation due to coupling of two loops through a vehicle is prevented by energizing the loops in succession. In Fig. 2 (not shown) two loops (L1 and L2) may be energized from the same oscillator (O) via a drive circuit (LD) and a transformer (T) coupled to the loops through respective blocking diodes. The presence of a vehicle in a loop alters the impedance and thereby alters the phase of the current in the drive circuit (LD); this phase change is detected by a phase discriminator (PD) feeding a signal amplifier (SA) coupled to output terminals (O1 and 02) through blocking diodes. A square wave is fed to diodes (D1 and D2) to couple one loop (L1) to the transformer (T) and at the same time to open further diodes (D5 and D6) thereby connecting one output terminal (O1 to an amplifier (SA), and a similar anti-phase square wave couples the other loop (L2) and the other output terminal (02). Storage capacitors (C6 and C7) retain the outputs (at terminals O1 and 02) between connection periods. The system is applicable to measuring the speed of a vehicle with two spaced detector loops.
GB2357264A 1964-06-08 1964-06-08 Improvements in or relating to road traffic detecting arrangements Expired GB1066475A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB2357264A GB1066475A (en) 1964-06-08 1964-06-08 Improvements in or relating to road traffic detecting arrangements

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB2357264A GB1066475A (en) 1964-06-08 1964-06-08 Improvements in or relating to road traffic detecting arrangements

Publications (1)

Publication Number Publication Date
GB1066475A true GB1066475A (en) 1967-04-26

Family

ID=10197845

Family Applications (1)

Application Number Title Priority Date Filing Date
GB2357264A Expired GB1066475A (en) 1964-06-08 1964-06-08 Improvements in or relating to road traffic detecting arrangements

Country Status (1)

Country Link
GB (1) GB1066475A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4368428A (en) * 1979-08-09 1983-01-11 U.S. Philips Corporation Method and arrangement for determining the velocity of a vehicle
EP0126958A2 (en) * 1983-05-28 1984-12-05 Robert Bosch Gmbh Moving objects data registering detector

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4368428A (en) * 1979-08-09 1983-01-11 U.S. Philips Corporation Method and arrangement for determining the velocity of a vehicle
EP0126958A2 (en) * 1983-05-28 1984-12-05 Robert Bosch Gmbh Moving objects data registering detector
EP0126958A3 (en) * 1983-05-28 1986-10-15 Robert Bosch Gmbh Moving objects data registering detector and analyzing method

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