| 摘要 |
PURPOSE:To continuously obtain a detection voltage proportional to the velocity of rotation for the angle of 360 degrees by providing a fixed disc with generating coils with the interval of 180 degrees and by conducting selective taking synchronously with the rotation of a permanent magnet rotary sidc magnetized for an N pole at an angle of more than 180 degrees. CONSTITUTION:A rotating shaft 1 is connected to the shaft of a rotating machine whose velocity is to be detected. A doughnut-shaped permanent magnet rotary disc 6 is magnetized for an N pole in the range of an angle of 270 degrees, for instance, while the remaining range is magnetized for an S pole, and it is fixed to the shaft 1 by a yoke disc 7 made of a high-conductivity material. Generating coils 9 and 10 are wound in a toroidal shape on a doughtnut-shaped fixed disc 8 made of a high-conductivity material, being separated by an angle of 180 degrees and opposed coaxially to the disc 6. Moreover, magnetism-sensitive elements 11 and 12 are fixed int the vicinity of the disc 6, at positions separated by 45 degrees respectively in the counterclockwise and clockwise directions around setting point of the coil 9. The outputs of the elements 11 and 12 are added through phase detecting circuits 13 and 14 and given to a voltage selecting and composing circuit 15 to which the outputs of the coils 9 and 10 are added. Thus, a voltage proportional to the velocity of rotation is obtained at a terminal 16 at an angle of rotation of 360 degrees. |
