Driver warning system
US4278969A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 16, 1979 |
| Grant date | Jul 14, 1981 |
| Priority date | — |
| Expiry date | May 16, 1999 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB60W2540/18
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A driver warning system has a steering sensor with a light source and photocell mounted on the steering column and directing a light beam towards a strip having alternate bands of reflective and non-reflective material formed thereon. A circuit coupled to the photocell is provided for sensing the transition between a reflected beam and a non-reflected beam. The beam is radiated at a frequency to which the circuit is sensitive so that ambient light will not cause a false signal. A transducer is provided for sensing the vehicle speed and providing a corresponding voltage. The warning system is inoperative below a minimum vehicle speed. Alarm circuitry is actuated upon the absence of a transition for a predetermined time period, dependent on vehicle speed. Both the predetermined time period between transitions to trigger the alarm and the vehicle speed at which the system alarm is operative are adjustable with the predetermined time period between transitions varying with vehicle speed. The alarm is also actuated when the vehicle speed exceeds an adjustable level.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.