1. Field of the Invention
The invention is based on an electrical machine of the type which includes one sensor, a transducer wheel at which the sensor axially picks up a signal, an end face of the sensor being adjacent to an annular face on one face end of the transducer wheel, a shaft on which the transducer wheel is secured, a fixed bearing, and a loose bearing, in which bearings the shaft is supported, and a housing.
2. Description of the Prior Art
Electrically commutated motors (EC motors) in particular are controlled by way of the sensor-detected signals. To that end, how the sensor system is adapted is decisive with regard to the precision of the commutation times with which the various coils of the stator are switched. Optimal commutation precision is achieved whenever the electronics detect the phase zero crossover of the magnetic flux. Changes in this are expressed as switching errors and cause power distortion of the motor. One often-used sensor system comprises a sensor and a transducer wheel that furnishes the signals for the sensor. To achieve precise switching points, the sensor and the transducer wheel are positioned very close together. In this way, the switching error is reduced. Typically, this is achieved by assembling individual high-precision components. In addition, high-resonance sensor magnets are employed.
It is the object of the invention to create an axial assembly concept with which tolerances in electrical machines, especially EC motors, with axial sensor pickup can be reduced and the machines or motors can be put together with little effort or expense for assembly. The concept should be capable of being used with DC motors with a position detection system as well. This is attained by an electrical machine having the characteristics of claim 1.
USPTO Backgrounds
USPTO Backgrounds