JPH045065Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an abnormal operation monitoring device for stopping the operation of a tape recorder when an abnormality occurs in the operation of the tape recorder.

(Prior Art) Generally, a tape recorder records information converted into an electrical signal on a magnetic tape, and reproduces the information into an electrical signal when necessary. This recording or reproduction is performed by a magnetic head provided along the running path of the magnetic tape, and the magnetic tape is run at a constant speed during recording and reproduction.

The mechanism of a tape recorder can be broadly divided into a constant speed tape drive mechanism that runs the magnetic tape at a constant speed, a reel stand mechanism that winds and rewinds the magnetic tape, and a magnetic tape and magnetic head during recording or playback. It can be divided into head mechanisms, etc. that take appropriate measures.

The tape constant speed drive mechanism described above generally includes a capstan shaft, a pinch roller, a flywheel, a capstan motor, a belt, and the like.

In order to faithfully record or reproduce electrical signals, it is important to run the magnetic tape stably relative to the magnetic head, and it is important to reduce tension fluctuations so that stable head touch can be obtained. It becomes necessary.

(Problems to be Solved by the Invention) By the way, a general magnetic tape is made by applying fine ferromagnetic powder to a polymer film base such as polyester.

Therefore, when the magnetic tape is wound or rewound during recording or reproduction of information, magnetic particles of the magnetic tape adhere to the capstan shaft or the pinch roller. Therefore, the attached magnetic powder becomes electrically charged due to friction during winding and unwinding of the magnetic tape, which may cause the magnetic tape to become entangled due to static electricity. The magnetic tape will be damaged.

The present invention was developed in response to such circumstances, and an object of the present invention is to provide an abnormal operation monitoring device for a tape recorder that can prevent damage to the magnetic tape.

(Means for Solving the Problem) In order to achieve the above object, the abnormal operation monitoring device for a tape recorder of the present invention includes a rotation direction detection means for detecting the rotation direction of the reel stand, and a rotation direction detection means for detecting the rotation direction of the reel stand. An abnormality is detected when it is determined that the rotation direction of the reel stand is rotating in the opposite direction to the rotation direction determined in the forward or reverse operation mode, respectively, based on the output signal and the forward or reverse operation mode signal. The apparatus is characterized by comprising an abnormal operation determining means for outputting a signal, and a control means for stopping the rotational operation of the reel stand when the abnormality detection signal is output.

(Function) In the tape recorder abnormal operation monitoring device of the present invention, when it is determined that the rotation direction of the reel stand is rotating in the opposite direction to the rotation direction determined respectively in the forward or reverse operation mode, the reel stand Since we stopped the rotation of
The winding state of the magnetic tape can be made lighter.

(Example) Hereinafter, details of an example of the present invention will be described based on the drawings.

FIG. 1 shows an embodiment of a tape recorder abnormal operation monitoring device (hereinafter simply referred to as a monitoring device) of the present invention.

As shown in the figure, the monitoring device includes a rotation direction detection circuit 1, an abnormal operation determination circuit 2, and a stop control circuit 3.
and an alarm generation circuit 4.

The rotation direction detection circuit 1 detects the rotation direction of the reel stand.

The abnormal operation determination circuit 2 uses the output signal of the rotation direction detection circuit 1 and the control system of the tape recorder (not shown).
The current operating mode signal A supplied from
If the reel stand is not rotating in the direction corresponding to the operating mode, an abnormality detection signal is output.

The stop control circuit 3 stops the operation of the reel stand drive section (not shown) based on the abnormality detection signal from the abnormal operation determination circuit 2.

The alarm generation circuit 4 controls predetermined operations of a buzzer, lamp, display, etc. based on the abnormality detection signal from the abnormal operation determination circuit 2.

The rotation direction detection circuit 1 includes light receiving elements 5a and 5b that detect the rotational state of the reel stand, and first and second differentiating circuits 8a and 8b that differentiate the output signals S1 and S2 from each of the light receiving elements 5a and 5b. is provided. The rotational direction detection circuit 1 also includes an AND gate 9 which receives output signals D1 and D2 from the first and second differentiating circuits 8a and 8b, and inverters 11a and 11.
The first and second differentiating circuits 8a, obtained through b.
An AND gate 10 is provided which receives output signals D1' and D2' from 8b.

The AND gates 9 and 10 output a rotation detection signal B indicating a counterclockwise direction and a rotation detection signal C indicating a clockwise direction, respectively.

FIG. 2 shows the positional relationship between each light receiving element 5a, 5b and the reel stand. A light emitting element 7 is arranged on one side of a slit plate 6 coaxially fixed to the rotating shaft 5 of the reel stand. has been done. Moreover, the above-mentioned light receiving elements 5a and 5b are arranged at positions facing the light emitting element 7 on the other side.

FIG. 3 shows the shape of the slit plate 6, which is shaped like a windmill having blades 6a, 6a, . . . . Further, one side of each blade 6a is a straight line extending radially from the center, and the other sides are curved. Therefore, when the slit plate 6 rotates clockwise, each light receiving element 5
Output signals from a and 5b that match the falling part
S1 and S2 are output, and when the slit plate 6 rotates counterclockwise, the respective light receiving elements 5a and 5b output signals S1 and S2 whose rising portions coincide.

Next, output signals from each component inside the rotation direction detection circuit 1 will be explained.

First, when the reel stand on the take-up side rotates clockwise according to the play mode on the reverse side,
As shown in FIGS. 4a and 4b, the light receiving elements 5a and 5b output signals S1 and S2 whose falling portions match. These output signals S1 and S2 are differentiated by the first and second differentiating circuits 8a and 8b, respectively, so that these circuits generate signals showing only the rising and falling portions as shown in c and d of the figure.
D1 and D2 are output. And these signals
The AND gate 9 which receives D1 and D2 as inputs outputs a signal B that does not contain "1 level", as shown in FIG.

On the other hand, since the AND gate 10 inputs the output signals D1' and D2' shown in e and f of the figure, a signal C including "1 level" is output as shown in h of the figure. Ru.

Therefore, the signal C is detected by the rotation direction detection circuit 1.
If it is output from , it indicates that the reel stand is rotating clockwise.

On the other hand, when the reel stand rotates counterclockwise, the light-receiving elements 5a and 5b output signals S1 and S2 whose rising portions match, as shown in FIGS. 5a and 5b. These output signals S1 and S2 are the first
By being differentiated by the second differentiating circuits 8a and 8b, the signals D1 and D1, which show only the rising and falling portions as shown in c and d of the same figure, are obtained from these circuits.
D2 is output. And these signals D1, D2
The AND gate 9 inputting the signal B outputs a signal B containing "1 level" as shown in FIG.

On the other hand, since the AND gate 10 inputs the inverted outputs of the outputs c and d in the figure, a signal C that does not include the "1 level" is output as shown in f in the figure.

Therefore, the signal C is detected by the rotation direction detection circuit 1.
If it is output from , it indicates that the reel stand is rotating counterclockwise.

Next, the operation of the monitoring device having such a configuration will be explained in the sixth section.
This will be explained using figures.

First, the play button on the tape recorder (not shown)
When is operated, it is determined whether or not it is a forward play (step 1). In the case of forward play, the rotation direction of the take-up reel stand is determined based on the output signals B and C from the rotation direction detection circuit 1 (step 2).
If it is rotating counterclockwise, the process returns to (Step 1); if it is rotating clockwise, it is in an abnormal state, so it moves to (Step 3), and after entering stop mode, the rotation of the capstan shaft is stopped. It is stopped (step 4).

If it is determined in step 1 that it is not a forward play, it is determined whether or not it is a reverse play (step 5). If it is determined that it is a reverse play, the direction of rotation of the reel stand on the supply side is determined (step 6). If it is rotating clockwise, the process returns to (Step 1), and if it is rotating counterclockwise, it moves to (Step 3), and after entering the stop mode, the rotation of the capstan shaft is stopped ( Step 4).

If it is determined in step 5 that the mode is not reverse play, it is determined whether the mode is fast forward mode or not (step 7). If it is determined that the mode is fast forward mode, the process moves to (step 2) and the same flow as above is followed. On the other hand, if it is determined that the mode is not fast forward mode, it is determined whether or not the mode is rewind mode (step 8). If it is determined that it is the rewind mode, the process moves to (step 6) and the same flow as above is followed.

On the other hand, if it is determined that the rewind mode is not in effect, it is determined whether or not the rewind mode is in the stop mode (step 9). If it is determined that it is in the stop mode, it is determined whether or not the reel stand is stopped (step 10). If the reel stand has not stopped, move on to (Step 3).
Follow the same flow as above. If it is determined that the reel stand is stopped or if it is determined that it is not in the stop mode (step 9),
Go to (Step 1) and follow the same flow as above.

In this way, in this embodiment, each operation mode is compared with the rotation state of the reel stand, and when it is determined that the reel stand is rotating in the opposite direction to the rotation direction determined in each operation mode, The rotation operation of the reel stand was stopped.

Therefore, even if the magnetic tape is wound around the capstan shaft, it is possible to quickly stop the reel stand, making it possible to reduce the amount of winding, thereby preventing damage to the magnetic tape. is prevented.

In addition, in this embodiment, when an abnormal condition is detected, the user is notified of the occurrence of the abnormality, so that when the abnormality occurs, measures can be taken immediately such as cleaning the capstan shaft and pinch roller. It can also be encouraged.

(Effects of the invention) As explained above, according to the tape recorder abnormal operation monitoring device of the present invention, when the tape recorder performs an abnormal operation, the operation is quickly stopped and the magnetic tape is wound. Since the tampering state is made lighter, it is possible to prevent damage due to engulfment of the magnetic tape.

[Brief explanation of the drawing]

Fig. 1 is a block circuit diagram showing an embodiment of the abnormal state detection device for a tape recorder according to the present invention, Fig. 2 is a side view showing the main parts of Fig. 1, and Fig. 3 shows the slit plate of Fig. 2. 4 and 5 are diagrams showing the output signals of each component inside the rotational direction detection circuit of FIG. 1, and FIG. 6 is a diagram showing the operation of the abnormal state detection device of the tape recorder of FIG. This is a flowchart. DESCRIPTION OF SYMBOLS 1... Rotation direction detection circuit, 2... Abnormal operation determination circuit, 3... Stop control circuit, 4... Alarm generating circuit, 5a, 5b... Light receiving element, 6... Slit plate, 7... Light emitting element.

Claims (1)

[Scope of utility model registration request] A rotation direction detection means for detecting the rotation direction of the reel stand, and a rotation direction detecting means for detecting the rotation direction of the reel stand in the forward or reverse operation mode, respectively, based on an output signal from the rotation direction detection means and a forward or reverse operation mode signal. abnormal operation determining means for outputting an abnormality detection signal when it is determined that the reel is rotating in the opposite direction to a predetermined rotational direction; and control for stopping the rotational operation of the reel stand when the abnormality detection signal is output. What is claimed is: 1. An abnormal operation monitoring device for a tape recorder, comprising: means.