Basf Aktiengesellschaft

Harold E Arns

Gerhard Rotter

Donald L Burdorf

James Bjordahl

Abraham Bejerano

Roger S Kincel

George J Bennett

An optical control system for use with a transducer positioning apparatus of a type having a lead screw coupled to the transducer head for controllably positioning the head relative to a selected track on a recording medium, wherein the lead screw is controllably rotated by a geneva mechanism that includes a geneva wheel coupled to the head screw and a geneva driver driven by a reversible d-c motor. The optical control system includes an optical disc that rotates in correspondence with the geneva driver and that has two optical tracks, one utilized in producing an error signal that varies substantially linearly with the angular position of the disc and the other utilized in producing an engagement pulse signal whenever the pin of the geneva driver is engaged in a slot in the geneva wheel. When it is desired to index the transducer head to a selected track, a pulse is coupled to the motor to drive the geneva driver in the appropriate direction, such pulse being terminated only after it has been determined that the geneva driver pin has rotated out of engagement with a slot in the geneva wheel. Thereafter, the error signal is coupled to the motor to automatically position the pin away from the geneva wheel and thereby hold the wheel, and thus the transducer head, in their respective positions.

Optical control system for transducer positioning apparatus

The present invention relates generally to a transducer positioning and adjusting apparatus and, more particularly, to an improved system for accurately and reproducibly positioning a transducer head in vertical relationship to a series of parallel horizontal tracks on a recording medium such as magnetic video tape. The apparatus comprises a frame upon which the elements of the system are mounted and with respect to which they are vertically aligned. A cam having a plurality of horizontally planar steps formed about its upper surface is rotatably mounted upon said frame and a vertically moveable bearing post, which is secured at one end to the transducer head, is held in continuous contact with the stepping surfaces formed on the cam. A ball bearing which contacts the underside of the cam substantially beneath the stepping surface upon which the bearing post is held in contact is utilized to support the cam on the mounting frame and maintain said stepping surface in precise vertical alignment therewith. A horizontally slidable wedge mounted on said frame upon which the cam supporting ball bearing rides may be utilized to vertically adjust said cam bearing post with respect to the mounting frame. A commutator disk secured to said cam in a predetermined relationship with respect to the stepping surfaces formed thereon electrically signals the position of said cam with respect to said bearing post. A logic circuit is also disclosed which controls the operation of a cam drive motor in response to the signals received from said commutator disk.

Transducer positioning device

A turnaround control arrangement for a color video recording and playback system, in which a color burst frequency at turnaround time is recorded during a certain vertical blanking interval in a distinct pattern; and in which, in playback the tape reversal operation is initiated at least partially under control of this distinct pattern. This 'turnaround flag' is also used to control the insertion of the sound signal carrier frequency of the system during turnaround, thereby to reduce the noise due to the loss of the recorded sound signal during turnaround in playback.

Turnaround system

A system for automatically loading and tensioning a supply reel of magnetic recording which is contained in a tape cassette. The system is designed to be utilized with a tape transport mechanism of the type wherein the supply reel is driven by surface engagement of the outermost layer of tape on the reel with a capstan. A motor driven leadscrew mechanically engages the tape transport apparatus and functions as a means for sequencing its operation in a manner so that upon loading, the normally-closed cassette is opened and the tape pack is advanced by the transport apparatus into an operative position in which it is in contact with the capstan. Following the threading of the tape about the take-up reel, the leadscrew causes the transport apparatus to withdraw the supply tape pack from close contact with the capstan in order to allow slack to be removed therefrom through the action of a brake upon the supply reel. The supply tape pack is then once again brought back into its operative position in contact with the capstan.

Cassette loading and tape tensioning system

An apparatus for automatically threading a supply reel of magnetic recording tape equipped with a self starting leader into a tape transport mechanism of the type in which take-up and supply reels are simultaneously driven by surface engagement of a capstan with the outermost tape layer on each reel.

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Chino, CA, United States of America

Harold E Arns