JPS6117566Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a reel stand drive mechanism in a magnetic recording/reproducing device.

When rapidly forwarding a tape in a magnetic recording/reproducing device, such as a VTR (video tape recorder), the load on the supply reel, load on the tape guide, and load on the cylinder are applied, so it is necessary to apply strong torque to the take-up reel stand. However, the braking force on the supply reel stand must be released. Similarly, in the case of rewinding, it is necessary to apply strong torque to the supply reel stand and release the braking force on the take-up reel stand. Furthermore, in the stopped state, it is necessary to apply strong braking force to each reel stand in order to prevent the tape from slackening.

Therefore, in the past, in VTRs, brake devices and idler devices were separately provided to perform operations such as fast forwarding, rewinding, and stopping the tape, and brakes and idlers were installed for each reel stand according to each operation mode. They were connected and separated using auxiliary means such as solenoids.

The present invention has been devised in view of the above points, and provides a reel stand drive mechanism that drives and stops the reel stand by a simple mechanism without using auxiliary means such as solenoids.

An embodiment of the present invention will be described below with reference to the drawings. In the figure, 1 is a supply reel stand, 2 is a take-up reel stand, 3 is a drive pulley, 4 is a drive motor that drives the drive pulley 3 via a belt 5 and has a relatively large inertia, 6 and 7 are the a first rotatably supported with friction on the rotating shaft of the drive pulley 3;
The second levers 8, 9 are the first and second levers 6, 7.
The first and second idlers 10 and 11 supported above and always in pressure contact with the drive pulley 3 have one end supported by the chassis and the other end supported by the first and second levers 6 and 7, respectively. the first and second idlers 8;
The springs 12 and 13 which bias the levers 9 in the direction of pressing against the supply reel 1 and the take-up reel 2, respectively, are stoppers that restrict the rotation of the first and second levers 6 and 7 to a predetermined angle.

FIG. 1 is an explanatory diagram of the stopped state of the mechanism of the present invention. In this state, the drive motor 4 and the drive pulley 3 are stopped, and the first and second levers 6, 7
are biased counterclockwise and clockwise by springs 10 and 11, respectively. This bias causes the first
The lever 6 connects the first idler 8 to the supply reel stand 1;
The second lever 7 takes up the second idler 9 on the reel stand 2
Press them into contact with each other. At this time, even if each reel stand 1, 2 attempts to rotate, it will be braked by the large inertia of the drive motor 4 and will remain in a stopped state.

FIG. 2 is an explanatory diagram of the fast-forwarding state. Now, when the drive pulley 3 starts to rotate clockwise, the second lever 7 is urged to rotate clockwise, and the take-up reel stand 2
rotates clockwise via the second idler 9 that is in pressure contact with the second idler 9. On the other hand, the first lever 6 rotates clockwise against the bias of the spring 10 due to friction with the rotating shaft of the drive pulley 3, and stops at the position where it abuts against the stopper 12. As a result, the first idler 8 that had been in pressure contact with the supply reel stand 1 separates, so that the braking is released and the supply reel stand 1 becomes free, and the tape is wound onto the take-up reel stand 2.

During rewinding, the supply reel stand 1 rotates counterclockwise to take up the tape due to the reverse rotation of the drive motor 4 in a completely opposite operation to that during fast forwarding, and at this time the take-up reel stand 2 becomes free. .

During recording and playback at normal speed, the operation is substantially the same as during fast forwarding, only the rotation speed of the drive motor 4 is lowered.

Note that when applying braking force to each reel stand in a stopped state, a motor with a large moment of inertia may be used, but a motor that is electrically braked may also be used. That is, at the same time as the stop operation, a reverse current is applied to the motor to instantly stop the motor, and in the stopped state, electrical braking is applied to the motor to prevent each reel from rotating easily.

As described above, according to the present invention, fast forwarding, rewinding operations, and application of braking force to the reel stand in the stopped state can be performed by one simple mechanism, which is practical.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a stopped state of the reel stand drive mechanism in an embodiment of the present invention, and FIG. 2 is an explanatory diagram of the same fast-forwarding state. Description of main drawings, 1... Supply reel stand, 2...
Take-up reel stand, 3... Drive pulley, 4... Drive motor, 6, 7... First and second levers, 8, 9...
1st, 2nd idler, 10, 11...Spring, 1
2,13...Stoppa.

Claims (1)

[Claims for Utility Model Registration] A drive pulley driven by a drive motor and capable of rotating in forward and reverse directions; first and second idlers that are always in pressure contact with the drive pulley; first and second levers that are coaxially supported on a drive pulley; and the first and second levers are moved in a direction that presses the first idler against the supply reel stand and presses the second idler against the take-up reel stand. a stopper that limits the amount of movement of the first and second levers that rotate against the bias of the spring, and when stopped, the first lever is biased by the spring when stopped; and a second idler simultaneously presses against the drive pulley whose drive has been stopped and the supply and take-up reel stands, respectively, to perform a stop braking operation, and when the drive pulley rotates forward, the first idler contacts the supply reel stand. The first lever oscillates against the spring and comes into contact with the stopper until the second idler moves away from the take-up reel stand when the drive pulley reverses. A reel stand drive mechanism characterized in that two levers swing against the spring and come into contact with the stopper.