| 摘要 |
1,064,888. Measuring rotor unbalance; phase angle and power factor measurement. GENERAL MOTORS CORPORATION. June 10, 1965 [June 19, 1964], No. 24545/65. Headings GIN and G1U. The angular position of the unbalance of a rotor 10 is measured electrically and indicated by a freely rotatable magnetic vane 50, the position of the vane being used to locate the rotor 10 after the test in the correct angular disposition for unbalance correction by a mechanism 12 which adds (or subtracts) material to the extent indicated by the magnitude of the unbalance signal, stored at 80. The rotor 10 is mounted on a spindle 16 coupled to a drive motor 18. The unbalance is sensed by a pick-up 28, giving a sinusoidal voltage output which is squared at 30 and fed to one winding 34 of a phase meter 32. The drive motor 18 is also coupled to a reference generator 26 giving a 2-phase output of the same frequency as the unbalance signal, which is fed to quadrature windings 38, 40 of phase meter 32. The vane 50 will therefore align itself with the direction of the resulting rotating magnetic field at the instant in each cycle that the unbalance pulse is produced, thus indicating on a scale 54 the phase position of the unbalance. Motor 18 is now de-energized and winding 34 of phase meter 32 is connected to a point 75 between the two quadrature rotor windings 62 of a resolver 58, whose stator winding 60 is fed with A. C. at standard power frequency, e. g. 60 cps. The connections between the free ends of windings 62 is such that at point 75 a voltage is developed whose amplitude is constant and whose phase is determined by the angular position of rotor windings 62. This voltage is fed to winding 34 of phase meter 32, to produce at the unearthed junction of windings 38, 40 a voltage whose amplitude is also constant and whose phase is determined by the angular position of the magnetic vane 50. This voltage is compared at 76 with the energizing A. C. in winding 60, and any difference is rectified and used to energize a motor 68 which drives the rotor windings 62 of resolver 58 and the test rotor 10 to line up with vane 50. The test rotor is now correctly positioned with respect to the unbalance correcting mechanism 12. The sequence of events measuring, indexing, correcting is effected by a switch 14 or automatically by a timer. |
