Torque sensing apparatus for an electric assist steering system

A torque sensing apparatus comprising:

• a first sensor element having a first part connectable to an input shaft and a second part adjacent and rotatable relative to said first part of said first sensor element and connectable with an output shaft, at least one of said first and second parts of said first sensor element being operative to receive an electrical signal from another of said first and second parts of said first sensor element, the electrical signal varying as a function of relative position between said first and second parts of said first sensor element;
• and
• a second sensor element having a first part connectable to the input shaft and a second part adjacent and rotatable relative to said first part of said second sensor element and connectable with the output shaft, said second sensor element being spaced from and substantially diametrically opposed from said first sensor element relative to a central axis extending between said first and second sensor elements, at least one of said first and second parts of said second sensor element being operative to receive an electrical signal from another of said first and second parts of said second sensor element, the electrical signal varying as a function of relative position between said first part and said second part of said second sensor element, the electrical signals of said first and second sensor elements varying in an inverse relationship in response to non-rotational relative movement between said first and second parts of said first sensor element and said first and second parts of said second sensor element.

A sensor assembly comprising:

• a substantially disk-shaped substrate having a central axis extending therethrough, said substrate being operatively connectable to one of an input shaft and an output shaft;
• a first sensor element having a first part connected with said substrate and a second part adjacent and rotatable relative to said first part of said first sensor element, said second part of said first sensor element being connectable to one of the input shaft and the output shaft which is free from being operatively connectable to said substrate, said first sensor element being operative to provide an electrical signal which varies as a function of the relative position between said first and second parts of said first sensor element;
• and
• a second sensor element having a first part connected with said substrate and a second part adjacent and rotatable relative to said first part of said second sensor element, said second part of said second sensor element also being connectable to one of the input shaft and the output shaft which is free from being operatively connectable to said substrate, said second sensor element being substantially diametrically opposed from said first sensor element, said second sensor element being operative to provide an electrical signal which varies as a function of the relative position between said first and second parts of said second sensor element, the electrical signals of said first and second sensor elements varying in an inverse relationship in response to non-rotational relative movement between said first parts of said first and second sensor elements and the respective said second parts of said first and second sensor elements.

A torque sensing apparatus for an electric assist steering system, said apparatus comprising:

• an input shaft having a central axis extending longitudinally through said input shaft;
• an output shaft substantially coaxial with said input shaft, said input shaft being rotatable relative to said output shaft about the central axis;
• a torsion member connected to said input shaft and said output shaft to resist relative rotation between the input shaft and the output shaft;
• and
• a torsion sensor adapted to provide an indication of relative rotational movement between said input shaft and said output shaft and to attenuate effects of side loading on said indication.