To provide a method and a control circuit, in which very versatile safe and comfortable features can be attained only by adding electronic components of the basic properties to simple and inexpensive microcontrollers.
An electric motor 44 drives a belt spool of a seat belt retractor for vehicles that use drive circuits 18, 36 for driving a microcontroller 16 and the motor. Each PWM control signal source 22 supplies a control signal with duration time different from the control pulses of other PWM control signal sources to its control signal outputs, when a trigger pulse is impressed to its trigger inputs. A program selection signal is supplied from a central sensor unit of a vehicle, to the trigger inputs of the PWM control signal sources. The PWM control signal sources that supply signal outputs from the PWM control signal sources to the drive circuits, in a control sequence defined by the selected control program.
PROKSCHA MARTIN
Tadashi Masui
Yasushi Kobayashi
Akio Chiba
Hiroyuki Tomita
Fumitoshi Nishiyama