Rolling bearing

A rolling bearing comprising:

• an outer ring having a predetermined rotation axis;
• an inner ring disposed coaxially with the outer ring, and situated on an inner peripheral side of the outer ring;
• multiple rolling elements disposed between the outer ring and the inner ring;
• and
• a strain gauge disposed on an outer peripheral surface of the outer ring or an inner peripheral surface of the inner ring,
• wherein the strain gauge includes three or more detector elements that are disposed on the outer peripheral surface of the outer ring or the inner peripheral surface of the inner ring, and
• wherein the three or more detector elements include at least two detector elements at different locations in a circumferential direction of the outer ring or the inner ring, the at least two detector elements being situated at different locations in a direction of the rotation axis,
• wherein the three or more detector elements are three or more resistors,
• wherein the three or more resistors are each arranged such that a grid direction of the resistor is parallel to the circumferential direction of the outer ring or the inner ring, and
• wherein the three or more resistors include at least three resistors at different locations in the circumferential direction and the direction of the rotation axis.

A rolling bearing comprising:

• an outer ring having a predetermined rotation axis;
• an inner ring disposed coaxially with the outer ring, and situated on an inner peripheral side of the outer ring;
• multiple rolling elements disposed between the outer ring and the inner ring;
• and
• a strain gauge disposed on an outer peripheral surface of the outer ring or an inner peripheral surface of the inner ring,
• wherein the strain gauge includes three or more detector elements that are disposed on the outer peripheral surface of the outer ring or the inner peripheral surface of the inner ring,
• wherein the three or more detector elements include at least two detector elements at different locations in a circumferential direction of the outer ring or the inner ring, the at least two detector elements being situated at different locations in a direction of the rotation axis,
• wherein the three or more detector elements are three or more resistors,
• wherein each of the resistors is formed of a film including Cr, CrN, and Cr2N, and
• wherein each of the resistors includes CrN and Cr2N at 20 wt % or less.

A rolling bearing comprising:

• an outer ring having a predetermined rotation axis;
• an inner ring disposed coaxially with the outer ring, and situated on an inner peripheral side of the outer ring;
• multiple rolling elements disposed between the outer ring and the inner ring;
• and
• a strain gauge disposed on an outer peripheral surface of the outer ring or an inner peripheral surface of the inner ring,
• wherein the strain gauge includes three or more detector elements that are disposed on the outer peripheral surface of the outer ring or the inner peripheral surface of the inner ring,
• wherein the three or more detector elements include at least two detector elements at different locations in a circumferential direction of the outer ring or the inner ring, the at least two detector elements being situated at different locations in a direction of the rotation axis,
• wherein each of the multiple detector elements is a detector element configured to detect a magnetic change that occurs in accordance with strain that is generated at the outer peripheral surface of the outer ring or the inner peripheral surface of the inner ring,
• wherein the three or more detector elements are each arranged such that a grid direction of the detector element is parallel to the circumferential direction of the outer ring or the inner ring, and
• wherein the three or more detector elements include at least three detector elements at different locations in the circumferential direction and the direction of the rotation axis.

A rolling bearing comprising:

• an outer ring having a predetermined rotation axis;
• an inner ring disposed coaxially with the outer ring, and situated on an inner peripheral side of the outer ring;
• multiple rolling elements disposed between the outer ring and the inner ring;
• and
• a strain gauge disposed on an outer peripheral surface of the outer ring or an inner peripheral surface of the inner ring,
• wherein the strain gauge includes three or more detector elements that are disposed on the outer peripheral surface of the outer ring or the inner peripheral surface of the inner ring,
• wherein the three or more detector elements include at least two detector elements at different locations in a circumferential direction of the outer ring or the inner ring, the at least two detector elements being situated at different locations in a direction of the rotation axis,
• wherein each of the multiple detector elements is a detector element configured to detect a magnetic change that occurs in accordance with strain that is generated at the outer peripheral surface of the outer ring or the inner peripheral surface of the inner ring,
• wherein each of the detector elements includes a structure of a magnetic tunnel junction in which an insulating film is interposed between magnetic films, and
• wherein each detector element includes a detector element configured to detect a magnetic change that occurs in the structure in accordance with strain that is generated at the outer peripheral surface of the outer ring or the inner peripheral surface of the inner ring.