Multiple-channel rotary transformer circuit in a magnetic recording

Abstract

A multiple-channel rotary transformer circuit is used in a magnetic recording and/or reproducing apparatus provided on a rotary structure with a plurality of sets of rotary magnetic heads, each set comprising at least two rotary magnetic heads, and having a signal recording and reproducing circuit associated with the rotary magnetic heads. The rotary transformer circuit comprises a rotary transformer comprising a rotor having a plurality of groups of coils respectively connected to the individual rotary magnetic heads of the plurality of sets of rotary magnetic heads and rotating together with said rotary structure, and a stator having coils disposed to respectively confront corresponding coils of the rotor thereby to carry out transfer of signals between the coils of the rotor and the coils of the stator, and switches changed over in accordance with a selected mode of signal recording and reproducing and operating to short-circuit the both ends of each of the stator coils confronting the coils of the rotor connected to the rotary magnetic heads of sets not being used out of the plurality of sets of rotary magnetic heads and, at the same time, to substantially close, with respect to the signal recording and reproducing circuit, the coils of the stator confronting the coils of the rotor connected to the set of rotary magnetic heads being used.