JPS5916339B2 - magnetic recording and reproducing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic recording/reproducing apparatus such as an audio tape recorder or a video tape recorder, and an object of the present invention is to electrically configure a tape running amount display means so that the display by the display means can be omitted. The objective is to be able to reliably stop the tape running at the tape position where the tape becomes.

In general, digital tape counters that electronically detect and display the rotation of the reel stand are able to measure the rotational force of the reel stand by measuring the elongation of the belt and the pulley section compared to conventional mechanical tape counters that operate via the belt. There is no slippage during operation, resulting in a significant improvement in accuracy.

Taking advantage of its high accuracy and ease of altitude control as it is electronic, it can be used to reset Cow 9 Fern to zero at a specific location on the tape, such as at the beginning of a recorded song, rewind after recording, or fast forward. Then, the specific position, that is, the zero count position is called. However, in this case, if a stop command is issued when the count reaches zero during high-speed fast forwarding or rewinding, an overflow will occur due to the slight time delay until the mechanism brake actually acts and the inertia of the traveling system. In other words, there is a problem that the tape runs beyond a certain position, so the position at which the tape stops is, for example, 99° in the case of rewinding.
It may be 9, or 001 in the case of fast forwarding, and an error will always occur with respect to the specific position 000. Therefore, the present invention can eliminate the above-mentioned error by correcting the overrun and performing a convergence operation.
This is an attempt to improve the reliability of an electronic tape counter, and one embodiment thereof will be described below with reference to the drawings. First, the basic operating principle of the magnetic recording/reproducing apparatus of this embodiment is to output the next operation command in accordance with various operation modes and perform control so as to converge errors. 1 Automatic stop of the tape counter at a specific position (O position) in the rewind operating state 2 Automatic stop of the tape counter at a specific position (O position) in the play (playback) operating state I 3 Identification of the tape counter in the fast forward operating state position(
Automatic stop at position O) The specific configuration will be explained below with reference to the drawings.

FIG. 1 is a configuration diagram of the apparatus of this embodiment. 1 is a take-up reel stand, and the outer periphery of this take-up reel stand 1 has 4 N, S, N, S marks on the circumference as shown in the figure. A polarized ring-shaped magnet 2 is attached. An integrated circuit is formed by combining Hall ICs 3 and 4, that is, a Hall element serving as a magnetoelectric conversion means, and an amplifier for amplifying the output from the Hall element so as to be close to the magnet 2 and facing the magnet 2. Since it is fixedly provided, when the reel stand 1 rotates, the alternating magnetic field from the magnet 2 causes both holes C3 to
, 4, an output voltage is generated. Moreover, since both ICs 3 and 4 are fixed around the rotating shaft of the reel stand 1 with an angle shifted by 135 degrees, as shown in FIG. The phases of the output voltages of both 1C3 and 1C4 differ depending on the time. This difference in phase is determined by a rotational direction discrimination circuit 5, and the output signal of the rotational direction discrimination circuit 5 is used to control the up-down counter 6 at the next stage to be in addition mode during forward rotation, and to be in subtraction mode during reverse rotation. . The up-down counter 6 is configured to count the reel stand rotation speed detection output from the Hall IC 3. With this configuration, for example, when a stop command is issued during fast-forward or rewind operation, a mechanical brake is applied to the take-up reel stand 1, and the reel stand 1 stops rotating until the tape actually stops. The counting operation of the counter can completely follow even an overrun of the rotation speed or a sudden reversal of the rotational direction when a rewind operation is commanded from a fast forward operation state. The BCD output of the up-down counter 6 (2
The evolution 10 output power) is input to the BCD-J component decoder/driver 7, and its output is used to detect the 10-digit light emitting elements, each consisting of a plurality of 7-segment light-emitting elements arranged on the panel.
The count number, that is, the rotation speed of the reel stand 1, is displayed on the decimal display 8.
In addition, the amount of tape travel is displayed.

The switch S1 is used to reset the contents of the counter 6, and when the counter 6 is reset by operating the switch S, "000" is displayed on the display 8.

The counter 6 is also connected to a logic judgment circuit 9, and this logic judgment circuit 9 receives the operation mode commands of the device, that is, the play (PLAY) operation command, the fast forward (FF) operation command, and the rewind (REW) operation command. Judging from the operation mode at the time when the contents of the counter 6 are set to 000, the next command to be given to the device, that is, a stop (StOp) operation command, a play operation command, or a rewind operation command, is determined and determined. This outputs the operation commands that have been given.

This logic follows the operation explanatory diagram in FIG.
When it becomes 0, a play operation command is output, and when the display on the display 8 becomes 000 during the subsequent play operation, a stop operation command is issued. It is possible to correct the error caused by the stoppage and accurately stop the tape at a specific position (in this embodiment, the position where the display 8 shows "000"). The switch S2 is used to select whether or not to perform the memory function in the logic judgment circuit 9. When the switch S2 is not closed, the display 8 shows "0".
00'', there is no change in the operation mode and the same operation mode is continued.

As explained above, the magnetic recording/reproducing apparatus of the present invention is a purely electronic system that includes a reversible counting means for counting the number of rotations of the reel stand as a means for displaying the amount of tape travel, and an electrical display means for displaying the count contents of this counting means. The output of the display means is added to a control circuit that changes the three operating modes, first to third, and tape running is always stopped at a specific display position of the display means, regardless of the tape running state. It is possible to ensure the display operation of the display means, significantly improve the reliability of the display, and also to reliably control the running of the tape according to the display. Its practical effects are significant.

[BRIEF DESCRIPTION OF THE DRAWINGS] Fig. 1 is a block diagram of the main parts of a magnetic recording and reproducing device according to an embodiment of the present invention, and Fig. 2 A and B show two output waveforms from the rotation speed detection means of the reel stand of the same device. FIG. 3 is an explanatory diagram of the operation of the logic determination circuit. 1...Take-up reel stand, 2...Magnet, 3, 4...Hall IC, 5...Rotation direction determination circuit, 6... ...Up-down counter, 7...Decoder and driver 8...
-Display unit, 9...Logic judgment circuit.

Claims (1)

[Scope of Claims] 1. Rotation speed detection means consisting of a plurality of detection elements arranged at predetermined intervals with respect to the reel stand and directly detecting the rotation speed of the reel stand, and a plurality of detections from this rotation speed detection means. A reversible device that includes a rotational direction determining means for determining the rotational direction of the reel stand based on the phase difference of the output, and a reversible device for counting the rotational speed output of the reel stand detected by the rotational speed detection means, the calculation being controlled by the output from the rotational direction determining means. a counting means, an electrical display means for displaying the counting result of the reversible counting means, a reset means for resetting the reversible counting means and setting the display of the display means to 0, and the display means in a rewinding operation state. When the display on the display means becomes 0, a regeneration operation command is output, and when the display on the display means becomes 0, a stop operation command is output. When the display becomes 0, a rewind operation command is output, and then when the display on the display means becomes 0, a playback operation command is output, and then when the display on the display means becomes 0. A magnetic recording and reproducing apparatus comprising: second control means for outputting a stop operation command; and third control means for outputting a stop operation command when the display becomes 0 in the reproducing operation state. 2 Claims comprising selection means for selecting whether or not to output an operation command when the display on the display means becomes 0 while the first, second, and third control circuits are in an operable state. 2. The magnetic recording and reproducing device according to item 1.