Speed correction system for a video disk playback system

Claim 2

In a disc playback system including an apparatus for recovering recorded signals from a spirally grooved disc record, said apparatus including a pickup device subject to positioning in the disc record groove for developing a recorded signal output, and means for rotating said disc record to establish relative motion between said disc record groove and said pickuP device, wherein a predetermined speed of said relative motion is desired for proper operation of said apparatus, a speed correction system comprising: 1. first speed error correction means for adjusting the speed of rotation of said record to maintain the average speed of said relative motion at substantially the predetermined speed when the operation of said first speed error correction means is initiated; 2. second speed error correction means for supplementing the speed error correction afforded by said first speed error correction means, said second speed error correction means including: A. circuit means responsive to the signal output of said pickup device for developing an error signal representative of deviations of the instantaneous relative speed between said disc record groove and said pickup device from said predetermined speed; and B. transducer means, coupled to said circuit means and normally responsive to said error signal, for varying the position of said pickup device in relation to said disc record groove in a manner that opposes said deviations; and 3. means responsive to the presence of said recorded signals in the output of said pickup device for delaying the operation of said transducer means relative to initiation of said first speed error correction means operation, thereby permitting (a) adjustment of the average speed of said relative motion to substantially the predetermined speed, and (b) stabilization of said circuit means for developing an error signal, to precede the operation of said transducer means.

Claim 3

second speed error correction means for supplementing the speed error correction afforded by said first speed error correction means, said second speed error correction means including: A. circuit means responsive to the signal output of said pickup device for developing an error signal representative of deviations of the instantaneous relative speed between said disc record groove and said pickup device from said predetermined speed; and B. transducer means, coupled to said circuit means and normally responsive to said error signal, for varying the position of said pickup device in relation to said disc record groove in a manner that opposes said deviations; and

Claim 4

second speed error correction means for supplementing the speed error correction afforded by said first speed error correction means, said second speed error correction means including: A. circuit means responsive to the signal output of said pickup device for developing an error signal representative of deviations of the instantaneous relative speed between said disc record groove and said pickup device from said predetermined speed; and B. transducer means, coupled to said circuit means and normally responsive to said error signal, for varying the position of said pickup device in relation to said disc record groove in a manner that opposes said deviations; and

Claim 5

A speed correction system as defined in claim 1 further including a control means responsive to the presence of said recorded signals in the output of said pickup device for initiating the operation of said first speed error correction means and said circuit means for developing an error signal.

Claim 6

A speed correction system as defined in claim 1 wherein said transducer means includes a means for supporting said pickup device, said supporting means being subject to a correcting motion in response to the error signal output of said circuit means.

Claim 7

means responsive to the presence of said recorded signals in the output of said pickup device for delaying the operation of said transducer means relative to initiation of said first speed error correction means operation, thereby permitting (a) adjustment of the average speed of said relative motion to substantially the predetermined speed, and (b) stabilization of said circuit means for developing an error signal, to precede the operation of said transducer means.

Claim 8

means responsive to the presence of said recorded signals in the output of said pickup device for delaying the operation of said transducer means relative to initiation of said first speed error correction means operation, thereby permitting (a) adjustment of the average speed of said relative motion to substantially the predetermined speed, and (b) stabilization of said circuit means for developing an error signal, to precede the operation of said transducer means.

Claim 9

A speed error correction system as defined in claim 1 wherein the free running speed of rotation of said record provided by said record rotating means is above said predetermined speed, and wherein said first speed error correction means comprises: means for developing a second error signal representative of deviations of the average speed of said storage medium from the predetermined speed; and means responsive to said error signal for braking said record rotating means in a manner that opposes said average speed deviations.

Claim 10

A speed error correction system as defined in claim 2 wherein said control means, in response to the absence of said recorded signals at the output of said pickup device, disables the operation of said first speed error correction means and said transducer means.

Claim 11

In a record playback system including an apparatus for recovering recorded signals from a storage medium by a pickup device, and means for driving said storage medium for establishing relative motion between said storage medium and said pickup device, wherein a predetermined speed of said relative motion is desired for proper operation of said apparatus, a speed correction system comprising: low frequency error correction means for maintaining the average speed of said storage medium at substantially the predetermined speed; circuit means responsive to recorded signals recovered by said pickup device for developing an error signal representative of the deviation of the instantaneous relative speed between said storage medium and said pickup device from the average speed of said storage medium; transducer means, electrically coupled to said circuit means and mechanically coupled to said pickup device, for varying the position of said pickup device in relation to said storage medium in a manner that minimizes said error Signal; control means responsive to the initial presence of said recorded signals in the output of said pickup device for enabling the operation of said low frequency error correction means and said circuit means at the beginning of playback; and means coupled to said control means for delaying the operation of said transducer means relative to enabling of said low frequency error correction means and said circuit means for developing an error signal, thereby permitting (1) initial adjustment of the average speed of said storage medium to substantially the predetermined speed, and (2) stabilization of said circuit means, to precede the operation of said transducer means; wherein speed error correction by said transducer means supplements speed error correction by said low frequency error correction means during playback, subsequent to said initial speed adjustment and said circuit means stabilization, to maintain the instantaneous relative speed between said storage medium and said pickup device substantially at said predetermined speed.

Claim 12

In a record playback system including an apparatus for recovering recorded signals from a storage medium by a pickup device, and means for driving said storage medium for establishing relative motion between said storage medium and said pickup device, wherein a predetermined speed of said relative motion is desired for proper operation of said apparatus, a speed correction system comprising: low frequency error correction means for maintaining the average speed of said storage medium at substantially the predetermined speed; circuit means responsive to recorded signals recovered by said pickup device for developing an error signal representative of the deviation of the instantaneous relative speed between said storage medium and said pickup device from the average speed of said storage medium; transducer means, electrically coupled to said circuit means and mechanically coupled to said pickup device, for varying the position of said pickup device in relation to said storage medium in a manner that minimizes said error Signal; control means responsive to the initial presence of said recorded signals in the output of said pickup device for enabling the operation of said low frequency error correction means and said circuit means at the beginning of playback; and means coupled to said control means for delaying the operation of said transducer means relative to enabling of said low frequency error correction means and said circuit means for developing an error signal, thereby permitting (1) initial adjustment of the average speed of said storage medium to substantially the predetermined speed, and (2) stabilization of said circuit means, to precede the operation of said transducer means; wherein speed error correction by said transducer means supplements speed error correction by said low frequency error correction means during playback, subsequent to said initial speed adjustment and said circuit means stabilization, to maintain the instantaneous relative speed between said storage medium and said pickup device substantially at said predetermined speed.

Claim 13

A speed correction system as defined in claim 6 wherein said transducer means includes a means for supporting said pickup device, said supporting means being subject to a correcting motion in response to the error signal output of said circuit means.

Claim 14

A speed correction system as defined in claim 6 wherein said means for driving said storage medium is adapted to provide a free running speed for said storage medium which is above said predetermined speed, and wherein said low frequency error correction means comprises: means for developing an error signal representative of the deviation of the average speed of said storage medium from the predetermined speed; and means responsive to said error signal for braking said storage medium in a manner that minimizes said error signal.

Claim 15

A speed error correction system as defined in claim 6 wherein said control means, in response to the absence of said recorded signals at the output of said pickup device, disables the operation of said low frequency error correction means and said transducer means.

Claim 16

In a video disc playback system, including apparatus for recovering recorded composite video signals, inclusive of synchronizing components, from a spirally grooved video disc record, said apparatus including a pickup device subject to positioning in the video disc record groove for providing an output comprising the recorded composite video signals, and means for rotating said disc record to establish relative motion between said disc record groove and said pickup device, wherein a predetermined speed of said relative motion is desired for operation of said apparatus; a speed correction system comprising: transducer means, mechanically coupled to said pickup device, for varying the position of said pickup device in relation to said disc record groove; circuit means, coupled to the output of said pickup device and responsive to synchronizing components of recorded composite video signals appearing in said output, for developing an error signal indicative of deviations of the instantaneous relative speed between said disc record groove and said pickup device from said predetermined speed; means for applying said error signal to said transducer; control means, coupled to the output of said pickup device, for developing an enabling signal in response to the presence of synchronizing components in said output, said control means including means for delaying the initiation of said enabling signal development relative to the initiation of error signal development by said circuit means; and a control device, electrically coupled to said transducer means and responsive to the enabling signal developed by said control means, for enabling said transducer means to respond to said error signal by varying the position of said pickup device in a manner opposing said deviations; said control device serving to preclude said transducer meaNs from responding to said error signal in the absence of said enabling signal.

Claim 17

In a video disc playback system, including apparatus for recovering recorded composite video signals, inclusive of synchronizing components, from a spirally grooved video disc record, said apparatus including a pickup device subject to positioning in the video disc record groove for providing an output comprising the recorded composite video signals, and means for rotating said disc record to establish relative motion between said disc record groove and said pickup device, wherein a predetermined speed of said relative motion is desired for operation of said apparatus; a speed correction system comprising: transducer means, mechanically coupled to said pickup device, for varying the position of said pickup device in relation to said disc record groove; circuit means, coupled to the output of said pickup device and responsive to synchronizing components of recorded composite video signals appearing in said output, for developing an error signal indicative of deviations of the instantaneous relative speed between said disc record groove and said pickup device from said predetermined speed; means for applying said error signal to said transducer; control means, coupled to the output of said pickup device, for developing an enabling signal in response to the presence of synchronizing components in said output, said control means including means for delaying the initiation of said enabling signal development relative to the initiation of error signal development by said circuit means; and a control device, electrically coupled to said transducer means and responsive to the enabling signal developed by said control means, for enabling said transducer means to respond to said error signal by varying the position of said pickup device in a manner opposing said deviations; said control device serving to preclude said transducer meaNs from responding to said error signal in the absence of said enabling signal.

Claim 18

A speed correction system in accordance with claim 10 also including average speed error correcting means, to which said record rotating means is responsive, for adjusting the average speed of said relative motion to substantially said predetermined speed prior to said enabling of said transducer means and for maintaining the average speed of said relative motion substantially at said predetermined speed during the operation of said transducer means.