Magnetic sound recording and reproducing apparatus of the spiral scanning type

Claim 1

A MAGNETIC SOUND RECORDING AND REPRODUCING APPRARATUS COMPRISING MEANS FOR HOLDING A MAGNETIC DISC IN A FIXED POSITION, A TURNTABLE BENEATH SAID HOLDING MEANS, DRIVE MEAND FOR ROTATING SAID TURNTABLE, DRIVING MEANS, MEANS COUPLED BETWEEN SAID DRIVE MEANS AND SAID TURNTABLE, REVERSING CLUTCH MEANS COUPLED BETWEEN SAID DRIVE MEANS AND SAID TURNTABLE FOR DRIVING SID TURNTABLE IN REVERSE, A MAGNETIC HEAD MOUNTED ON SAID TRUNTABLE FOR MOVEMENT RAIDALLY OF SAID TURNTABLE AND ACROSS THE MAGNETIC DISC, A CAM PLATE MOUNTED FOR ROTATION ABOUT THE SAME AXIS AS SAID TRUNTABLE, SAID CAM HAVING A SPIRAL EDGE ENGAGED WITH SAID MAGNETIC HEAD, FURTHER CLUTCH MEANS COUPLED BETWEEN SAID TURNTABLE AND SAID CAM PLATE FOR ROTATING SAID CAM WITH SAID TURNTABLE AND RELTIVE TO SAID TURNTABLE THROUGH ONLY A FRACTION OF A REVOLURION FOR EACH REVOLUTION OF SAID TRUNTABLE, BRAKE MEANS ENGAGEABLE WITH SAID TURNTABLE, AND CONTROL MEANS FOR ENGAGING AND DISCENGAGING SAID CLUTCH MEANS, SAID BRAKE MEANS AND SAID REVERSING CLUTCH MEANS IN A PRESET SEQUENCE SO THAT IT IS POSSIBLE TO REPRODUCE DURING RECORDING A PORTION OF THE MATERIAL PREVIOUSLY RECORDED.