CIRCUIT AND METHOD FOR ESTABLISHING TWO-WAY COMMUNICATION BETWEEN THE STEERING COLUMN AND THE STEERING WHEEL OF A VEHICLE

The disclosed invention comprises an electronic control circuit for transferring power and data signals between an electronic circuit associated with a vehicle steering column and an electronic circuit associated with a vehicle steering wheel. Communication between the column circuit and the wheel circuit is accomplished by a rotary transformer having a primary and a secondary magnetic coil, wherein the primary magnetic coil is associated with the steering column and the secondary magnetic coil is associated with the steering wheel. The column circuit and the wheel circuit both include data signals that are transferred to the other across the rotary transformer. The column circuit also includes a power supply which provides power to the wheel circuit across the rotary transformer. Power supplied to the wheel circuit is stored in at least one storage device in the wheel circuit, which then provides the power to the components of the wheel circuit, including an air bag squib driver circ uit for firing air bag squibs. La invencion divulgada comprende un circuito electronico de datos (20) para transferir energia y senales de datos entre un circuito electronico asociado con una columna de direccion (22) de un vehiculo y un circuito electronico asociado con un volante de direccion (24) de un vehiculo. La comunicacion entre el circuito de columna (22) y el circuito de volante (24) es lograda por un transformador giratorio (XI) que tiene una bobina magnetica primaria y una bobina magnetica secundaria, donde la bobina magnetica primara (40) esta asociada con la columna de la direccion y la bobina magnetica secundaria (60) esta asociada con el volante de la direccion. El circuito de columna (22) y el circuito de volante (24) incluyen ambos senales de datos que son trnasferidas de uno a otro a traves del transformador giratorio (XI). El circuito de columna (22) tambien incluye una fuente de energia (26) que proporciona energia al circuito de volante (24) a traves del transformador giratorio (XI). La energia suministrada al circuito de volante (24) es almacenada en al menos un dispositivo de almacenamiento (C1, C2) en el circuito de volante (24), que luego provee la energia a los componentes del circuito de volante (24), incluyendo un circuito excitador de cebo electrico de bolsa de aire (68) para disparar cebos electricos de bolsas de aire.