Arrangement for generating a clock frequency signal for recording information on a data carrier

Claim 2

Arrangement for generating a clock frequency signal for recording digital information on a data carrier such as a magnetic tape or the like driven by a brushless direct-current drive motor having a permanent magnet rotor, a stator winding and electronic circuit means for inducing voltages in the stator winding in dependence upon the changing position of the rotor to produce a rotating stator field, the arrangement comprising monitoring means connected to the electronic circuit meaNs for providing a first signal varying in correspondence to the rotating stator field, and signal conversion means connected to said monitoring means for converting said first signal into said clock frequency signal synchronized to the speed of rotation of the rotor, said clock frequency signal alternately assuming one of two values, the time of transisition between said values being negligible.

Claim 3

The arrangement of claim 1 wherein the stator winding includes component windings and wherein the electronic circuit means induces emf voltages in the component windings respectively for producing the rotating stator field, said monitoring means comprising signal transmission circuits connected to the component windings respectively, said conversion means comprising comparators for converting said first signals into respective second signals of rectangular waveform, said comparators being connected to corresponding ones of the component windings through respective ones of said transmission circuits, and an exclusive-OR circuit having a plurality of inputs receiving said second signals respectively for forming therefrom said periodic waveform synchronized to the speed of rotation of the rotor.

Claim 4

The arrangement of claim 3, each of said signal transmission circuits containing a diode for coupling out the corresponding emf voltage.

Claim 5

Arrangement for generating a clock frequency signal for recording digital information on a data carrier such as a magnetic tape or the like driven by a brushless direct-current drive motor having a permanent magnet rotor, a stator winding and electronic circuit means for inducing voltages in the stator winding in dependence upon the changing position of the rotor to produce a rotating stator field, the electronic circuit means including detectors disposed in the field of the permanent magnet rotor for providing respective first signals indicative of the changing position of the rotor, the arrangement comprising monitoring means connected to the electronic circuit means for providing a first signal varying in correspondence to the rotating stator field, said monitoring means including signal transmission circuits connected to the outputs of respective ones of the detectors; and signal conversion means connected to said monitoring means for converting said first signal into a periodic waveform synchronized to the speed of rotation of the rotor, said waveform alternately assuming one of two values, the time of transition between said values being negligible, said signal conversion means including comparators for converting said first signals into respective second signals of rectangular waveform, said comparators being connected to corresponding ones of the detectors through respective ones of said transmission circuits, and an exclusive-OR circuit having a plurality of inputs receiving said second signals respectively for forming therefrom said periodic waveform synchronized to the speed of rotation of the rotor.

Claim 6

Arrangement for generating a clock frequency signal for recording digital information on a data carrier such as a magnetic tape or the like driven by a brushless direct-current drive motor having a permanent magnet rotor, a stator winding and electronic circuit means for inducing voltages in the stator winding in dependence upon the changing position of the rotor to produce a rotating stator field, the electronic circuit means including detectors disposed in the field of the permanent magnet rotor for providing respective first signals indicative of the changing position of the rotor, the arrangement comprising monitoring means connected to the electronic circuit means for providing a first signal varying in correspondence to the rotating stator field, said monitoring means including signal transmission circuits connected to the outputs of respective ones of the detectors; and signal conversion means connected to said monitoring means for converting said first signal into a periodic waveform synchronized to the speed of rotation of the rotor, said waveform alternately assuming one of two values, the time of transition between said values being negligible, said signal conversion means including comparators for converting said first signals into respective second signals of rectangular waveform, said comparators being connected to corresponding ones of the detectors through respective ones of said transmission circuits, and an exclusive-OR circuit having a plurality of inputs receiving said second signals respectively for forming therefrom said periodic waveform synchronized to the speed of rotation of the rotor.