Hazard display system

• US 6,055,465 A
• Filed: 12/19/1997
• Issued: 04/25/2000
• Est. Priority Date: 12/19/1996
• Status: Expired due to Fees

• Current Assignee: Yazaki Corporation
• Original Assignee: Yazaki Corporation
• Inventors: Matsunaga, Mototatsu
• Primary Examiner(s): Chin, Gary
• Application Number:
  US08/995,012
• Time in Patent Office: 858 Days
• Field of Search: 701/1, 701/36, 701/49, 307/10.1, 307/10.8, 340/426, 340/428, 340/438, 340/439, 340/468, 340/471, 340/472, 340/473, 340/478
• US Class Current: 701/1
• CPC Class Codes: B60Q 1/46 for giving flashing caution signals during drive, other than signalling change of direction, e.g. flashing the headlights or hazard lights

Abstract

A flicker synchronizing signal generating section (23) generates a flicker synchronizing signal having a drive start-on time for front and rear hazard lamps (6a, 6b, 7a, 7b) set shorter than a drive start-off time in each period in accordance with a hazard signal and using the drive start-on time as a trigger period, a respective hazard output signal generating section (34, 44) generates a hazard output signal for having a drive of the hazard lamps start within the trigger period in accordance with the flicker synchronizing signal, with a drive-on time and a drive-off time set equal in each period thereof and with an interval from a start of the drive within each current trigger period to a start of the drive within the next trigger period set equal to the period of the flicker synchronizing signal, and a respective lamp driving section (33, 43) drives to flicker an associated hazard lamp in accordance with the hazard output signal.

Claims

1. A hazard display system, comprising:

a control unit configured to generate a multiplex control signal;

a hazard switch element configured, in response to being switched on, to signal to said control unit to include a flicker synchronizing signal in said multiplex control signal, wherein the period of said flicker synchronizing signal includes an ON state and an OFF state;

a first processor configured to process a first set of data to control a first load during normal operation in response to said multiplex control signal and to generate a first drive signal in response to being interrupted by said flicker synchronizing signal when said flicker synchronizing signal changes to said ON state;

a second processor configured to process a second set of data to control a second load during normal operation in response to said multiplex control signal and to generate a second drive signal in response to being interrupted by said flicker synchronizing signal when said flicker synchronizing signal changes to said ON state;

a first display element drivable by said first drive signal and configured to display a front flickering hazard signal, wherein the period of said front flickering hazard signal has an ON state and an OFF state; and

a second display element drivable by said second drive signal and configured to display a rear flickering hazard output signal, wherein the period of said rear flickering hazard output signal has an ON state and an OFF state, wherein said front flickering hazard signal and said rear flickering hazard signal are in said ON state at least twice during one period of said flicker synchronizing signal in order to reduce the number of times said first processor and said second processor are interrupted by said flicker synchronizing signal.

2. A hazard display system according to claim 1, further comprising:

a main control unit configured to compare an occurrence of the first drive signal with an occurrence of the second drive signal to check for a phase difference therebetween exceeding a threshold; and

a first timing control unit and a second timing control unit each configured to respond to the phase difference in order to have one of the first and second processors stop generating either the first drive signal or the second drive signal.

3. A hazard display system according to claim 1, wherein the first processor and the second processor are configured to generate the first drive signal and the second drive signal, respectively, such that the period of the first drive signal equals the period of the second drive signal.

4. A hazard display system according to claim 1, wherein the first processor is configured to generate the first drive signal such that the period of the first drive signal is dependent on a data processing rate of the first processor.

5. A hazard display system according to claim 1, wherein the flicker synchronizing signal comprises a trigger pulse for triggering generation of the first drive signal.

6. A hazard display system for driving front and rear hazard lamps to flicker in response to a hazard signal and a flicker synchronizing signal transmitted in a multiplex control signal, comprising:

a flicker synchronizing signal generating section configured to generate said flicker synchronizing signal having a period including a drive start-on time and a drive start-off time, wherein said drive start-on time is a trigger period and said drive start-on time is shorter than said drive start-off time;

a hazard output signal generating section comprising,

a first hazard output signal generating section configured to generate during said trigger period a front hazard output signal having a period including a drive-on time and a drive-off time, and

a second hazard output signal generating section configured to generate during said trigger period a rear hazard output signal having a period including a drive-on time and a drive-off time; and

a lamp driving section comprising,

a first driving section configured to drive the front hazard lamps such that said front hazard lamps flicker in accordance with the front hazard output signal, and

a second driving section configured to drive the rear hazard lamps such that said rear hazard lamps flicker in accordance with the rear hazard output signal, wherein

said drive-on time and said drive-off time of said front hazard output signal and said rear hazard output signal are equal to each other, respectively, and an interval from a start of the drive within each trigger period to a start of the drive within the next trigger period are set equal to the period of said flicker synchronizing signal in order to flicker said front and rear hazard lamps in a predetermined period.

7. A hazard display system according to claim 6, further comprising:

a front and rear hazard signal decision-making section configured to make a decision as to whether a phase difference between said front hazard output signal and said rear hazard output signal has exceeded a predetermined time interval after the front hazard lamps and the rear hazard lamps have flickered a predetermined number of times in accordance with the number of repetitions of said front hazard output signal and said rear hazard output signal, respectively; and

a timing control section configured to control the phase difference such that the phase difference exceeds the predetermined time interval in order to set the front hazard output signal and the rear hazard output signal to drive-off status until the front and rear hazard output signals enter drive-on status within a subsequent trigger period of the flicker synchronizing signal, respectively.

8. A hazard display system according to claim 6, wherein the hazard output signal generating section is cooperative with a central processing unit, and at least one of the drive start-on time and the drive start-off time of the flicker synchronizing signal is determined in dependence on a signal processing speed of the central processing unit.