| 摘要 |
PROBLEM TO BE SOLVED: To provide an apparatus for detecting wear of bearing in the axial direction of a canned motor which can detect wear of bearing in axial direction with higher accuracy even for variation of the power supply voltage of the canned motor. SOLUTION: An axial direction position detecting circuit 82 detects an axial direction position of a rotor from a difference of voltages generated in the axial direction position detecting coils Cf, Cr provided at both end portions of the axial direction of stator of the canned motor. An axial direction zero point adjusting circuit 83 adjusts to zero a voltage difference of the both axial direction position detecting coils Cf, Cr in the axial direction position detecting circuit 82, when the rotor is in the reference position of the axial direction using the voltage source which changes in proportion to the power supply voltage of the canned motor as the bias power supply. Even when the power supply voltage of the canned motor varies, a bias power supply of the axial direction zero point adjusting circuit 83 also changes without giving influence on the zero point adjustment by the axial direction zero point adjusting circuit 83. As a result, the axial direction wear can be detected with higher accuracy. |
