Torque sensor for a power assist steering system

A torque sensor for a power assist steering system for sensing applied torque between relatively rotatable input and output shafts, the input shaft being connected with the output shaft by a torsion element, said torque sensor comprising:

• a rotary input transformer for providing an input signal, said rotary input transformer including a primary winding and a secondary winding;
• a rotary transmitter connected for rotation with the input shaft, said rotary transmitter including a transmitter coil electrically connected with said secondary winding of said rotary input transformer, said rotary transmitter being operable to receive said input signal and transmit a transmitted signal related to said input signal;
• a rotary receiver axially spaced from said rotary transmitter and connected for rotation with the output shaft, said rotary receiver having a radially extending receiver face divided into a plurality of receiver pole segments by a plurality of radially extending slots,
• said rotary receiver including a receiver coil set for receiving said transmitted signal completely encircling each of all of said receiver pole segments individually, said receiver coil set having two sections disposed in each of all of said plurality of slots;
• and
• at least one rotary output transformer including a primary winding and a secondary winding, said primary winding of said at least one rotary output transformer being electrically connected with said receiver coil set, said rotary output transformer providing an output signal related to said transmitted signal.

A torque sensor for a power assist steering system for sensing applied torque between relatively rotatable input and output shafts, the input shaft being connected with the output shaft by a torsion element, said torque sensor comprising:

• a rotary input transformer including a primary winding and a secondary winding;
• a rotary transmitter connected for rotation with the input shaft, said rotary transmitter having a radially extending transmitter face divided into a plurality of transmitter pole segments by a plurality of radially extending first slots,
• said rotary transmitter including a transmitter coil electrically connected with said secondary winding of said rotary input transformer, said transmitter coil completely encircling each of all of said transmitter pole segments individually and having two sections disposed in each of all of said plurality of transmitter slots;
• a rotary receiver axially spaced from said rotary transmitter and connected for rotation with the output shaft, said rotary receiver having a radially extending receiver face divided into a plurality of receiver pole segments by a plurality of radially extending receiver slots,
• said plurality of receiver pole segments comprises alternating first and second receiver pole segment pairs, each of said first and second receiver pole segment pairs comprising an adjacent pair of said receiver pole segments, each of said first receiver pole segment pairs being disposed circumferentially between two of said second receiver pole segment pairs and being separated from said second receiver pole segment pairs by a first group of said plurality of receiver slots in said receiver face, a second group of said plurality of receiver slots in said receiver face extending between each of said adjacent pairs of said receiver pole segments in each of said first and second receiver pole segment pairs;
• said rotary receiver further including a first receiver coil and a second receiver coil, said first receiver coil completely encircling each of all of said first receiver pole segment pairs and having two sections disposed in each of all of said first group of receiver slots separating said first and second receiver pole segment pairs, said second receiver coil completely encircling each of all of a plurality of combined receiver pole segment pairs comprising one of said first receiver pole segment pairs and an adjacently disposed one of said second receiver pole segment pairs, said second receiver coil having two sections disposed in each of all of said second group of receiver slots extending between each of said adjacent pairs of said receiver pole segments in each of said first and second receiver pole segment pairs;
• and
• first and second rotary output transformers each including a primary winding and a secondary winding, said primary winding of said first rotary output transformer being electrically connected with said first receiver coil and said primary winding of said second rotary output transformer being electrically connected with said second receiver coil.