Record contact spindle

Claim 2

A playback system for disc records of the type having a centrally apertured major surface comprising exposed conductive material in the vicinity of the aperture and susceptible to accumulating an electric charge of sufficient magnitude to damage a pickup device for transducing said record comprising: a rotatable turntable and a record centering spindle mounted for rotation with said rotatable turntable, a conductive member mounted in said spindle for movement between (1) a first position sufficiently withdrawn within said spindle to permit record passage to a playback position centered about said spindle and supported by said turntable, and (2) a second position extending sufficiently from said spindle to permit electrical contact between said member and the exposed conductive material of a major surface of a record when said record is disposed in said playback position with said turntable in supporting contact with a surface of said record opposite to said major surface, And means coupling said conductive member through said spindle to a point of reference potential for said playback system.

Claim 3

The invention according to claim 1, wherein; said spindle has a recess therein, and said conductive member has a generally hooked shaped section formed at an end thereof, and wherein said playback system also includes means in said recess for pivotally mounting said conductive member to said spindle with said hooked shaped section extending out of said spindle and toward said turntable and resilient means coupled to said member for urging rotation of said hooked shaped section into contacting relation with a record when disposed on said turntable in said playback position.

Claim 4

In a playback system for recovering signals recorded in a grooved portion of a major surface of a disc type record, said major surface also including an ungrooved conductive region surrounding a central aperture in said disc record; said playback system including a rotatable turntable comprising conductive material and in supporting contact with a surface of said record opposed to said major surface when said record is in position for playback of said signals, and a spindle member mounted for rotation with said turntable and subject to protrusion through said record aperture when said record is in said playback position; apparatus comprising: first means including a conductive portion adapted to cooperate with said conductive region of said major surface of such a record to establish a conductive contacting relation therewith, means mounting said first means to said spindle member for movement between a first position when said spindle member is non-rotational and a second position in response to rotational motion of said spindle member, said first means in said first position being disposed in in a manner precluding record contact, said first means in said second position causing said conductive portion to engage said conductive region of said major surface of a record when said record is disposed on said turntable in said playback position, and means coupled to the conductive portion of said first means for providing a conductive path through said spindle member to said turntable.

Claim 5

In a playback system for recovering signals recorded in a grooved portion of a major surface of a disc type record, said major surface also including an ungrooved conductive region surrounding a central aperture in said disc record; said playback system including a rotatable turntable comprising conductive material and in supporting contact with a surface of said record opposed to said major surface when said record is in position for playback of said signals, and a spindle member mounted for rotation with said turntable and subject to protrusion through said record aperture when said record is in said playback position; apparatus comprising: first means including a conductive portion adapted to cooperate with said conductive region of said major surface of such a record to establish a conductive contacting relation therewith, means mounting said first means to said spindle member for movement between a first position when said spindle member is non-rotational and a second position in response to rotational motion of said spindle member, said first means in said first position being disposed in in a manner precluding record contact, said first means in said second position causing said conductive portion to engage said conductive region of said major surface of a record when said record is disposed on said turntable in said playback position, and means coupled to the conductive portion of said first means for providing a conductive path through said spindle member to said turntable.

Claim 6

The invention according to claim 3 and further including means for spring biasing said first means toward said first position.

Claim 7

The invention according to claim 3, wherein; said first means in said first position is disposed within a boundary defined by the projection of the periphery of said aperture in said record when said record is in said playback position.

Claim 8

In a playback system for use with a disc type record having a major surface including effectively exposed conductive material in a region thereof, said system including means for recovering recorded signals from said major surface of such a disc type record when such a record is disposed about a peripheral surface of a record spindle member in a playback position with a surface of such record opposed to said major surface resting upon a rotatable turntable, said record spindle member being mounted for rotation with said rotatable turntable; apparatus comprising: first means including a conductive portion adapted to cooperate with said major surface of such a record in said region thereof to establish a conductive contacting relation with said conductive material, means mounting said first means to said record spindle member for movement between a first position and a second position in response to rotational motion of said spindle member, said first means occupying said first position in the absence of rotational motion of said spindle member and said first means in said first position being disposed within said peripheral surface of said record spindle, said first means assuming said second position during rotational motion of said spindle member, and said first means in said second position protruding beyond the peripheral surface of said spindle an amount sufficient to cause said conducTive portion to engage said region of said major surface of such a record when disposed on said turntable in said playback position, and means coupled to the conductive portion of said first means for providing a conductive path through said spindle to a point of reference potential for said playback system.

Claim 9

In a playback system for use with a disc type record having a major surface including effectively exposed conductive material in a region thereof, said system including means for recovering recorded signals from said major surface of such a disc type record when such a record is disposed about a peripheral surface of a record spindle member in a playback position with a surface of such record opposed to said major surface resting upon a rotatable turntable, said record spindle member being mounted for rotation with said rotatable turntable; apparatus comprising: first means including a conductive portion adapted to cooperate with said major surface of such a record in said region thereof to establish a conductive contacting relation with said conductive material, means mounting said first means to said record spindle member for movement between a first position and a second position in response to rotational motion of said spindle member, said first means occupying said first position in the absence of rotational motion of said spindle member and said first means in said first position being disposed within said peripheral surface of said record spindle, said first means assuming said second position during rotational motion of said spindle member, and said first means in said second position protruding beyond the peripheral surface of said spindle an amount sufficient to cause said conducTive portion to engage said region of said major surface of such a record when disposed on said turntable in said playback position, and means coupled to the conductive portion of said first means for providing a conductive path through said spindle to a point of reference potential for said playback system.

Claim 10

The invention according to claim 6, wherein; said mounting for said first means includes means permitting translational movement of said first means in a direction angled toward said turntable in response to rotational motion of said spindle member.

Claim 11

In a system for playing back signals from a major surface portion of a disc type record which is disposed about a peripheral surface of a record spindle member, said record spindle member being mounted for rotation with a rotatable turntable adapted to support said record, and said major surface of said record including effectively exposed conductive material in a region thereof, apparatus comprising: first means including a conductive portion adapted to cooperate with a major surface of the record in said region to establish a conductive contacting relation with said conductive material; means mounting said first means to said record spindle member for movement between a first position when said spindle member is non-rotational and a second position in response to rotational motion of said spindle member; said first means in said first position being disposed within said peripheral surface of said record spindle; said first means in said second position protruding beyond the peripheral surface of said spindle an amount to cause said conductive portion to engage said region of the major surface of a record disposed on said turntable; means coupled to the conductive portion of said first means for providing a conductive path through said spindle; wherein said spindle member includes a channel communicating with the peripheral surface of said spindle member, and said first means comprises a slidable member disposed in said channel for movement therealong, and resilient means coupled to said slidable member are provided to bias said first means in said first position.

Claim 12

In a system for playing back signals from a major surface portion of a disc type record which is disposed about a peripheral surface of a record spindle member, said record spindle member being mounted for rotation with a rotatable turntable adapted to support said record, and said major surface of said record including effectively exposed conductive material in a region thereof, apparatus comprising: first means including a conductive portion adapted to cooperate with a major surface of the record in said region to establish a conductive contacting relation with said conductive material; means mounting said first means to said record spindle member for movement between a first position when said spindle member is non-rotational and a second position in response to rotational motion of said spindle member; said first means in said first position being disposed within said peripheral surface of said record spindle; said first means in said second position protruding beyond the peripheral surface of said spindle an amount to cause said conductive portion to engage said region of the major surface of a record disposed on said turntable; means coupled to the conductive portion of said first means for providing a conductive path through said spindle; wherein said spindle member includes a channel communicating with the peripheral surface of said spindle member, and said first means comprises a slidable member disposed in said channel for movement therealong, and resilient means coupled to said slidable member are provided to bias said first means in said first position.

Claim 13

The invention according to claim 8, wherein: said channel is angled in a given direction toward said turntable, and said slidable member is movable in response to the rotation of said spindle along said channel in said given direction to cause a force to be exerted through said conductive portion on the record when present on said turntable.

Claim 14

The invention according to claim 8, wherein: at least a portion of the supportive structure of said spindle member is formed of a conductive material, said slidable member includes conductive material serving as said conductive portion of said first means, and said resilient means comprises metallic spring means interconnecting said conductive material of said slidable member with said conductive material of said supportive structure of said spindle member.

Claim 15

A video disc playback system comprising, in combination: a centrally apertured disc of dielectric material having a major surface including a central ungrooved region adjacent the disc aperture, and an additional region surrounding said central region and impressed with a spiral groove, the bottom of said groove containing geometric variations representative of recorded video signal information; a layer of conductive material covering said dielectric material of said disc in both said central ungrooved region and said surrounding grooved region of said major surface; a layer of dielectric material overlying only a portion of said conductive layer, said portion being inclusive of the conductive material covering said grooved region but exclusive of the segment of said conductive material covering said ungrooved region in the immediate vicinity of said aperture; pickup means including a stylus subject to reception in said groove, for recovering said recorded video signal information; a conDuctive turntable for supporting said record and subject to rotation at a desired playback speed; a spindle mounted for rotation with said turntable; a conductive member supported in said spindle and subject to translational movements between first and second positions, said conductive member occupying said first position in the absence of rotational motion of said spindle member and assuming said second position in response to centrifugal force exerted thereon as a consequence of rotation of said spindle at said playback speed; said conductive member in said first position being located sufficiently close to the center of said spindle to preclude interference by said conductive member with passage of said record to a playback position in which said ungrooved region of said major surface surrounds said spindle, the grooved region of said major surface is accessible to said pickup means, and the surface of said record opposed to said major surface is in contact with said turntable; said conductive member in said second position protruding from said spindle in the direction of said turntable to a sufficient degree to ensure electrical contact between said conductive member and the conductive material of said layer segment during rotation of said record in said playback position at said playback speed; means for spring biasing said conductive member toward said first position, wherein the strength of said biasing is insufficient, relative to the magnitude of said centrifugal force at said playback speed, to prevent movement of said conductive member to said second position upon attainment of said playback speed, but is sufficient to substantially ensure return of said conductive member to said first position upon a cessation of the rotational motion of said spindle; and conductive means connected between said conductive member and said conductive turntable so that the capacitance exhibited between said conductive turntable and said conductive layer when said record is in said playback position is shunted by a conductive path comprising said conductive member and said conductive means upon record rotation at said playback speed.

Claim 16

A video disc playback system comprising, in combination: a centrally apertured disc of dielectric material having a major surface including a central ungrooved region adjacent the disc aperture, and an additional region surrounding said central region and impressed with a spiral groove, the bottom of said groove containing geometric variations representative of recorded video signal information; a layer of conductive material covering said dielectric material of said disc in both said central ungrooved region and said surrounding grooved region of said major surface; a layer of dielectric material overlying only a portion of said conductive layer, said portion being inclusive of the conductive material covering said grooved region but exclusive of the segment of said conductive material covering said ungrooved region in the immediate vicinity of said aperture; pickup means including a stylus subject to reception in said groove, for recovering said recorded video signal information; a conDuctive turntable for supporting said record and subject to rotation at a desired playback speed; a spindle mounted for rotation with said turntable; a conductive member supported in said spindle and subject to translational movements between first and second positions, said conductive member occupying said first position in the absence of rotational motion of said spindle member and assuming said second position in response to centrifugal force exerted thereon as a consequence of rotation of said spindle at said playback speed; said conductive member in said first position being located sufficiently close to the center of said spindle to preclude interference by said conductive member with passage of said record to a playback position in which said ungrooved region of said major surface surrounds said spindle, the grooved region of said major surface is accessible to said pickup means, and the surface of said record opposed to said major surface is in contact with said turntable; said conductive member in said second position protruding from said spindle in the direction of said turntable to a sufficient degree to ensure electrical contact between said conductive member and the conductive material of said layer segment during rotation of said record in said playback position at said playback speed; means for spring biasing said conductive member toward said first position, wherein the strength of said biasing is insufficient, relative to the magnitude of said centrifugal force at said playback speed, to prevent movement of said conductive member to said second position upon attainment of said playback speed, but is sufficient to substantially ensure return of said conductive member to said first position upon a cessation of the rotational motion of said spindle; and conductive means connected between said conductive member and said conductive turntable so that the capacitance exhibited between said conductive turntable and said conductive layer when said record is in said playback position is shunted by a conductive path comprising said conductive member and said conductive means upon record rotation at said playback speed.

Claim 17

Apparatus in accordance with claim 11 wherein said spring biasing means additionally serves as a portion of said conductive means.