JPS5931139B2 - magnetic recording and reproducing device - Google Patents

Description

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

In general, digital tape counters that electronically detect and count the rotation of the reel stand compare with conventional mechanical tape counters that operate via the belt to measure the rotational force of the reel stand due to belt elongation and pulleys. There is no slippage, resulting in a significant improvement in accuracy.

Taking advantage of its high accuracy and ease of altitude control due to its electronic nature, the counter can be reset at a specific location on the tape, such as at the beginning of a recorded song, and then rewinded or fast forwarded after recording. Recalling that particular position, ie, the zero count position, is performed. However, in this case, if a stop command is issued when the count reaches zero during high-speed fast forwarding or rewinding, an overrun will inevitably occur due to the slight time delay before the mechanism brake actually acts and the inertia of the traveling system. In other words, the problem arises that the tape runs past a specific position, so the position where the tape stops is, for example, 999 for rewinding, or 001 for fast forwarding, and is always 000.
An error will occur at a specific position. Therefore, the present invention is designed to eliminate the above-mentioned errors and improve the reliability of the electronic counter display by correcting the overrun and performing a convergence operation.

Furthermore, the present invention attempts to solve the following problems that occur when tape position control operations are performed by correcting such overruns. In other words, for example, if you set the counter to 0 at the beginning of the tape and then try to recall this starting end position by rewinding from the middle of the tape, or if you use a heavy tape and set the counter to 0 near the end. , if this position is attempted to be retrieved by rewinding from the end of the tape, tape overruns will almost never occur, and an operation to correct the overruns will not be able to be executed, causing the device to malfunction. There is a fear. Therefore, the present invention is designed to correctly stop the tape at a specific value position of the tape counter when such an overrun does not occur. An embodiment of the present invention 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. Automatic stopping of the tape counter at a specific position (0 position) in the 1-rewind operating state J Automatic stopping of the tape counter at a specific position (O position) in the 2-play (playback) operating state and above are basic operations,
Next, the automatic stop operation when no overrun occurs as described above will be described.

4. Automatic stop when no overrun occurs 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 Hall ICs to
Output voltage is generated at ports 3 and 4, and since both 1Cs 3 and 4 are fixed around the rotating shaft of reel stand 1 with an angle shifted by 135 degrees, winding is performed as shown in Figure 2 A and B. The phases of the output voltages of both ICs 3 and 4 are different when the reel stand 1 rotates forward and reverse. This difference in phase is determined by a rotational direction determining circuit 5, and the output signal of the rotational direction determining 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. There is. The upton counter 6 is configured to count the reel stand rotation speed detection output from the hole C3. 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 direction of rotation when rewinding from a fast forward operation state. BCD output of the uptan counter 6 (binary coded 1
0 evolution output) is input to the BCD-J component decoder/driver 7, and the output is used to display the count number or The number of revolutions of the reel stand 1 and, by extension, the amount of tape travel are displayed.

The first keyboard switch S1 is for resetting the contents of the counter 6 and is a TTL (Transi-StOrder) switch.
-TransistOr-LOgic) etc.
When the counter 6 is reset by controlling the switch S1 and resetting the counter 6, "000" is displayed on the display 8.

The counter 6 is also connected to a logic judgment circuit 10, and this logic judgment circuit 10 receives play (PLAY) operation commands, fast forward (FF) operation commands, and rewind (REW) operation commands from the operation mode command circuit 11 of the device. When the content of the counter 6 is reset to 000 in response to the command, the operation mode is judged from the operation mode, and the next command is given to the device, that is, stop (St
Op) It determines either an operation command, a play operation command, or a rewind operation command, and outputs the determined operation command.

The second keyboard switch S2 uses a purely electronic display means including a reversible counting means for counting numbers and an electrical display means for displaying the count contents of this counting means, and displays the output of this display means at the first switch. In addition to the control means for changing the second operation mode, the tape overrun is corrected in any state of tape running in rewinding or fast forwarding, and the tape running is always stopped at a specific display position of 000 on the display means. This makes it 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 in accordance with the display. Moreover, even if the beginning of the tape is set at a specific display position of 000 to prevent overruns from occurring, there will be no malfunction and the third control means will ensure that the tape stops at the specific display position of 001 on the display means. The practical effect is great.

[Brief explanation of the drawing]

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 rotational speed detection means of the reel stand of the same device as the reel stand rotates. FIG. 3 is an explanatory diagram of the operation of the logic determination circuit, and is a waveform diagram shown in comparison according to the direction. 1...Take-up reel stand, 2...Magnet, 3, 4...Hall IC, 5...Rotation direction determination circuit, 6...・・Upton counter,
7... Decoder and driver, 8...
Display unit, 10...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 second control means for outputting a stop operation command, and a state in which the first and second control means are operable, the display on the display means becomes 0 in the rewind operation state, a reproduction operation command is output, and the display A magnetic recording/reproducing apparatus comprising third control means for outputting a stop operation command when the display on the display means becomes 1 when the display on the display means is not subtracted from 0. 2. A patent claim comprising selection means for selecting whether or not to output an operation command when the display on the display means becomes 0 or 1 while the first, second, and third control means are in an operable state. The magnetic recording and reproducing device according to item 1.