Endless magnetic tape indicator apparatus with automatic index after a tape cycle

Claim 2

An endless magnetic tape playing time indicator apparatus for an endless magnetic tape recording and reproducing system of a type wherein there is provided tape drive means including a rotary drive capstan for driving the tape, an electrical circuit having a magnetic head, and track changing means for changing over record tracks to be played on the tape in response to a conductive strip on the tape, comprising: indication means having a rotary index member and a fixed scale member, said scale member including divisions relating to the tape playing time; transmission means for imparting rotation of said tape drive means to said rotary index member to rotate said rotary index member in a direction away from a predetermined starting position, said transmission means including a clutch device controlling transmission of drive power and a speed reducing device having a reduction ratio such that said index member does not make one rotation even if the tape is driven at one cycle; said speed reducing device having a rotary shaft on which said rotary index member is mounted, a pulley on an axle, a belt connecting said capstan and said pulley for rotation of said pulley at a reduced ratio, a worm coaxially mounted on said axle with said pulley, and a worm wheel mounted on said rotary shaft arranged to mesh with said worm; said clutch device including said worm wheel of said speed reducing device, a friction disk on said rotary shaft and opposed to one side of said worm wheel, and spring means urging said friction disk into frictional engagement with said worm wheel; return means for returning said index member to the starting position when said clutch device breaks off transmission of drive power, said return means including means for axially moving said rotary shaft in a direction to move said friction disk out of frictional engagement with said worm wheel against the bias of said spring means; and operation means responsive to the conductive strip on the tape for actuating said clutch device to break off said transmission of drive power, whereby said index member is automatically returned to the starting position.

Claim 3

An endless magnetic tape driving volume indicator apparatus for an endless magnetic tape recording and reproducing system in accordance with claim 1 wherein said index member is rigidly fixed to said rotary shaft of said speed reducing device, said return means is connected to said rotary shaft, and said spring means is adapted to impart rotation force to said rotary shaft in the direction to return said index member to its initial position.

Claim 4

An endless magnetic tape driving volume indicator apparatus for an endless magnetic tape recording and reproducing system in accordance with claim 2 wherein said operation means includes a contactor having a pair of feeler contacts electrically separated from one another and adapted to be shorted by said conductive strip on the tape, and a solenoid having a plunger connected to said clutch device to operate the same and being adapted to be energized by said contactor.

Claim 5

An endless magnetic tape playing time indicator apparatus for an endless magnetic tape recording and reproducing system of a type wherein there is provided tape drive means including a rotary drive capstan for driving the tape, an electrical circuit having a magnetic head, and track changing means for changing over record tracks to be played on the tape in response to a conductive strip on the tape, comprising indication means having a rotary index member and a fixed scale member, said scale member including divisions relating to the tape playing time; transmission means for imparting rotation of said tape drive means to said rotary index member to rotate said rotary index member in a direction away from a predetermined starting position, said transmission means including a clutch device controLling transmission of drive power and a speed reducing device having a reduction ratio such that said index member does not make one rotation even if the tape is driven at one cycle; said speed reducing device including a rotary shaft on which said rotary index member is mounted; a first gear rotatable by rotation force of said capstan, a first train of gearings having a first foremost gear meshing with said first gear, and a first backmost gear rotatably mounted to said rotary shaft, a second train of gearings having a gear ratio different from that of said first train of gearings and including a second foremost gear meshing with said first gear, and a second backmost gear rotatably mounted on said rotary shaft and being arranged to rotate in the direction opposed to said first backmost gear, and a second gear rotatably mounted on a rod extending from said rotary shaft at a right angle and interposed between said first backmost gear and said second backmost gear to engage those gears and being rotatable about said rod as well as said rotary shaft; return means for returning said index member to the starting position when said clutch device breaks off transmission of drive power; and operation means responsive to the conductive strip on the tape for actuating said clutch device to break off said transmission of drive power, whereby said index member is automatically returned to the starting position.

Claim 6

An endless magnetic tape playing time indicator apparatus for an endless magnetic tape recording and reproducing system of a type wherein there is provided tape drive means including a rotary drive capstan for driving the tape, an electrical circuit having a magnetic head, and track changing means for changing over record tracks to be played on the tape in response to a conductive strip on the tape, comprising indication means having a rotary index member and a fixed scale member, said scale member including divisions relating to the tape playing time; transmission means for imparting rotation of said tape drive means to said rotary index member to rotate said rotary index member in a direction away from a predetermined starting position, said transmission means including a clutch device controLling transmission of drive power and a speed reducing device having a reduction ratio such that said index member does not make one rotation even if the tape is driven at one cycle; said speed reducing device including a rotary shaft on which said rotary index member is mounted; a first gear rotatable by rotation force of said capstan, a first train of gearings having a first foremost gear meshing with said first gear, and a first backmost gear rotatably mounted to said rotary shaft, a second train of gearings having a gear ratio different from that of said first train of gearings and including a second foremost gear meshing with said first gear, and a second backmost gear rotatably mounted on said rotary shaft and being arranged to rotate in the direction opposed to said first backmost gear, and a second gear rotatably mounted on a rod extending from said rotary shaft at a right angle and interposed between said first backmost gear and said second backmost gear to engage those gears and being rotatable about said rod as well as said rotary shaft; return means for returning said index member to the starting position when said clutch device breaks off transmission of drive power; and operation means responsive to the conductive strip on the tape for actuating said clutch device to break off said transmission of drive power, whereby said index member is automatically returned to the starting position.

Claim 7

An endless magnetic tape playing time indicator apparatus for an endless magnetic tape recording and reproducing system in accordance with claim 4 wherein said clutch device comprises on said speed reducing device said first gear fixed to an axially slidable shaft, on said speed reducing device said first and second foremost gears meshing with said first gear, and a spring member urging said first gear in a direction meshing with said first and second foremost gears whereby said first gear meshes with said first and second foremost gears by elasticity of said spring member and engagement of said first gear with said first and second foremost gears are relieved when said shaft of said first gear is axially moved by said operation means against elasticity of said spring means.

Claim 8

An endless magnetic tape driving volume indicator apparatus for an endless magnetic tape recording and reproducing system in accordance with claim 4 wherein said clutch device comprises said second gear on said speed reducing device, on said speed reducing device said first and second backmost gears rotatably and slidably mounted to said rotary shaft and meshing with said second gear, a spring member urging said second backmost gear in the direction meshing with said second gear, and means for preventing said first backmost gear from moving from a predetermined position whereby normally said second gear meshes with said first and second backmost gears by elasticity of said spring member, engagement of said second gear with said first backmost gear being relieved when said rotary shaft is axially moved by said operation means against said spring member.