| 摘要 |
FIELD: physics; measurement. ^ SUBSTANCE: present invention pertains to measuring technology and can be used in security devices of hoisting cranes. Voltage is obtained at the output of two sensors, sensitive to the magnetic field of the earth, fitted on the revolving part of the crane. The sensors used are magnetoresistive bridges, the magnetic sensitive structures of which are oriented on one axis only. The axes of the sensors are orthogonal and are in the horizontal plane. Voltage at the output of one sensor is proportional to the sine of the angle of crane rotation relative magnetic field lines, and voltage at the output of the other sensor is proportional to the cosine of that angle. Before taking each reading from the sensor, the domains of their inner magnetic sensitive structures are oriented in the axis of easy magnetisation alternately in different directions using control current pulses. The metering circuit allows for taking sensor readings at time intervals between control current pulses. The value and polarity of the voltage are then determined, and the bearing angle is calculated. ^ EFFECT: simpler structure and technological effectiveness. ^ 3 cl, 3 dwg |
