US 5,675,449 A · Magnetic recording/reproducing device with wireless transmission of position control signal to head transducer on rotary drum

Abstract

The present invention provides a movable magnetic head unit including a signal transmission element. The movable magnetic head is mounted upon a rotary drum of a drum assembly which also includes a stationary drum, the rotary and stationary drums being supported by a shaft. The signal transmission element transmits a control signal wirelessly to the rotary drum to drive an electromechanical transducing element which moves the magnetic head. The signal transmission element may include rotary transformers, mounted on the rotary and stationary drums, facing each other. In a further embodiment, the signal transmission element may include an optical transmitter for optically transmitting the position control signal to an optical receiver mounted on the rotary drum. Wireless transmission of the position control signal prevents noises from appearing on a display, enables stable compensation of deviations of the magnetic head and improves reliability of the magnetic head unit.

Claims23

Dependent claims

A movable magnetic head unit comprising:

a rotary magnetic head for tracing a track of a magnetic tape;
an electromechanical transducing element for moving said rotary magnetic head in a direction vertical to the track of said magnetic tape, said electromechanical transducing element bearing said rotary magnetic head;
control signal generating means for generating a control signal for changing a position of said rotary magnetic head;
frequency modulation means for frequency modulating the control signal to output a frequency modulated signal;
frequency demodulation means for demodulating the frequency modulated signal and for providing the demodulated signal to said electromechanical transducing element;
and
transmission means for transmitting the frequency modulated signal from said frequency modulation means to said frequency demodulation means,
said transmission means including a rotary transformer having a plurality of concentric coils wound thereon, an outermost one of the plurality of concentric coils transmitting the frequency modulated signal.

5 more elements

A movable magnetic head unit comprising:

a rotary magnetic head for tracing a track of a magnetic tape;
electromechanical transducing means for moving said rotary magnetic head in a direction vertical to the track of said magnetic tape, said electromechanical transducing means bearing said rotary magnetic head;
control signal generation means for generating a control signal as a parallel digital signal for changing a position of said magnetic head;
parallel - serial signal conversion means for converting the parallel digital signal into a serial signal;
serial - parallel signal conversion means for converting the serial signal output by said parallel - serial signal conversion means into a parallel signal;
transmission means for wirelessly transmitting the serial signal output from said parallel - serial signal conversion means to said serial - parallel signal conversion means;
digital - analog conversion means for converting the parallel signal output by said serial - parallel signal conversion means into an analog signal and for outputting the analog signal as the control signal;
and
level detection means, coupled to said digital-analog conversion means and said transmission means, for detecting an amplitude level of the serial signal transmitted by said transmission means and for controlling said digital-analog conversion means to output the control signal to said electromechanical transducing means for changing the position of said rotary magnetic head to a predetermined position when the detected amplitude level of the serial signal is lower than a desired level.

6 more elements

A movable magnetic head unit comprising:

a rotary magnetic head for tracing a track of a magnetic tape;
an electromechanical transducing element for moving said rotary magnetic head in a direction vertical to the track of said magnetic tape, said electromechanical transducing element bearing said rotary magnetic head;
control signal generation means for generating a control signal for changing a position of said rotary magnetic head;
frequency modulation means for frequency modulating the control signal to output a frequency modulated signal;
frequency demodulation means for demodulating the frequency modulated signal and for providing the demodulated signal to said electromechanical transducing element;
transmission means for transmitting the frequency modulated signal from said frequency modulation means to said frequency demodulation means;
and
level detection means for detecting an amplitude level of the frequency modulated signal transmitted by said transmission means and for outputting the control signal to said electromechanical transducing element for changing the position of said rotary magnetic head to a predetermined position when the detected level is lower than a desired level.

5 more elements

Dependencies are inferred from the claim text.

Magnetic recording/reproducing device with wireless transmission of position control signal to head transducer on rotary drum

Life of this patent

Magnetic recording/reproducing device with wireless transmission of position control signal to head transducer on rotary drum

Life of this patent

Abstract

Claims23