Zigzag running warning system for automotive vehicles

• US 4,673,913 A
• Filed: 09/15/1982
• Issued: 06/16/1987
• Est. Priority Date: 10/28/1981
• Status: Expired due to Fees

• Current Assignee: Nippon Soken, Inc.
• Original Assignee: Nippon Soken, Inc.
• Inventors: Kago, Yoshiyuki, Akita, Shigeyuki
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): Queen, Tyrone
• Application Number:
  US06/418,529
• Time in Patent Office: 1,735 Days
• Field of Search: 340/52 R-54, 340/575, 340/576, 340/815.23, 340/941, 180/167, 180/168, 33/361, 324/207, 324/208, 324/251-254
• US Class Current: 340/439
• CPC Class Codes: B60R 16/0231 Circuits relating to the driving or the functioning of the vehicle monitoring tyres B60C23/00; indicating overspeed B60K31/00; for dash boards B60K37/00, B60Q3/10; for indicating emergencies B60Q1/52; brake control systems B60T; registering or indicating the working of vehicles G07C5/00; measuring distance G01C, e.g. combinations of speed and distance G01C23/00; engine indicators G01L; measuring speed or acceleration G01P

Abstract

In a zigzag running warning system for automotive vehicles which detects and gives a warning of zigzag running of a vehicle, a terrestrial magnetism sensor generates an electric signal having an amplitude varying in dependence on the direction of travel of the vehicle with respect to the direction of the terrestrial magnetism. An electronic unit in the system discriminates that vehicle is running in a zigzag direction when the amplitude of the electric signals changes in excess of a predetermined value at a period which is less than a predetermined time, and informs the driver of the zigzag running by a speaker, lamp or the like.

Claims

1. A zigzag running warning system for an automotive vehicle, comprising:

a magnetic sensor having an annular core, an excitation coil wound uniformly on said annular core, and a sensing coil wound to traverse said annular core;

an oscillator circuit for oscillating at a given frequency;

a driver circuit for receiving oscillations from said oscillator circuit and driving said excitation coil in response thereto;

an amplifier circuit for amplifying an output signal of said sensing coil which varies in amplitude in response to the superposition of terrestrial magnetism and magnetism produced by said excitation coil whenever it is driven by said driver circuit;

a detection circuit for envelope detecting an output signal of said amplifier circuit;

a change detecting circuit for generating an electric signal as a signal indicating that the direction of travel of said vehicle is changed in excess of a predetermined value when an output signal of said detection circuit is higher than a predetermined value;

an electronic unit responsive to said electric signal from said change detecting circuit to discriminate zigzag running of said vehicle as a condition existing when the direction of the terrestrial magnetism with respect to the direction of travel of said vehicle changes alternately with time, and to generate a warning signal when said zigzag running is discriminated; and

warning means responsive to a warning signal from said electronic unit for issuing a warning against said zigzag running condition.

2. A system according to claim 1, wherein said electronic unit discriminates that said vehicle is running in a zigzag direction by detecting also whether a period of said electric signal is less than a predetermined time.

3. A system according to claim 1, wherein said electronic unit discriminates that said vehicle is running in a zigzag direction when said electric signal is generated successively at a period less than a predetermined time.