Disk drive apparatus with intermittently operated servo signal processor for low power consumption

Claim 1

In a reproducing apparatus for use with a disk-like recording medium having interspersed servo and information signal zones in which servo and information signals, respectively, are recorded, and which includes a reproducing head mounted for movement so as to scan said servo and information signal zones alternatively and which provides a reproduced head output which contains reproduced servo signals and reproduced information signals while said head scans said servo and information signals zones, respectively; a device for controlling said movement of the head, comprising: servo signal processing means operative in response to a clock signal of a predetermined frequency for processing said reproduced servo signals contained in said head output and thereby generating a head control signal and for generating a processing period signal indicative of a processing period in which said servo signal processing means is processing said reproduced servo signals, said servo signal processing means ceasing said processing in the absence of said clock signal of said predetermined frequency; head driving means for controlling the movement of said head on the basis of said head control signal; clock generating means for generating said clock signal of said predetermined frequency; servo signal detecting means for detecting a servo signal reproducing interval in which said servo signals are contained in said head output reproduced from the disk-like recording medium and for generating a servo reproducing interval signal indicative of said servo signal reproducing interval; and control means for supplying said clock signal to said servo signal processing means during a supplying period beginning when said servo reproducing interval signal indicates said servo signals are contained in said head output and ending when said processing period signal indicates said servo signal processing means is no longer processing said reproduced servo signals.