JPH0210579Y2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Field of Industrial Application The present invention relates to a cassette-type tape recorder that uses a cassette tape in which a magnetic tape is stored in a container, and particularly relates to a malfunction prevention device.

(b) Conventional technology Cassette tape recorders are capable of recording, playing,
It is configured to perform various operations such as fast forwarding and rewinding, and is also configured to displace the magnetic head to bring it into contact with the magnetic tape during recording and reproducing operations. In order to displace the magnetic head from the stop position to the recording (playback) position, the magnetic head is generally mounted on a displacement plate called a sliding board. The movement of the sliding board to the recording (playback) position is performed by pressing the playback operation button, but recently a device has been developed that uses the rotational force of an electric motor. , such technology is, for example, developed in 1983.
There is one disclosed in Publication No. 62460. In addition, recently, technology has been developed that electronically controls the rotation of the electric motor and the switching operation to each operating state.
There is something disclosed in the publication No. In general, cassette tape recorders switch between recording and playback operations by switching a mechanical recording/playback switch, but as tape recorders become smaller, mechanical recording/playback switches are used. It has become difficult to arrange a changeover switch, and recently technology has been developed to electronically switch magnetic heads, amplifier circuits, etc. between recording and playback states. As a technique for electronically switching between recording operation and playback operation, there is a technique disclosed in, for example, Japanese Unexamined Patent Publication No. 42116/1983. Furthermore, as mentioned above, the cassette type tape recorder is equipped with a sliding board that moves from the stop position to the recording (playback) position, but as tape recorders become ultra-small, the amount of displacement of the sliding board has become shorter. Recently, tape recorders have been commercialized in which the magnetic head is in light contact with the magnetic tape when the tape recorder is in the stopped position. As such technology, for example,
There is one described in No. 127426. Furthermore, if power is supplied to the electric motor while the tape recorder is stopped, rewinding or fast forwarding operations can be performed.When the sliding board is displaced to the recording (playback) position due to recording or playback operations, the drive A tape recorder equipped with a drive mechanism capable of switching to a constant speed drive state has been commercialized, and such technology is described in Japanese Patent Application No. 59-23734.

(c) Problems to be solved by the invention The operation is switched by the aforementioned operation circuit, and the recording/playback switching operation is also carried out electronically, and furthermore, when the magnetic head is in a stopped state, the magnetic head is in light contact with the magnetic tape. A cassette-type tape recorder that is configured to enter a rewind or fast-forward operation state when the electric motor rotates when the tape recorder is in a stopped state has the following problems. That is, if a large shock is given to the tape recorder by dropping or the like while the tape recorder is in the recording operation state, the lock of the sliding board which was in the recording operation position is released, and the sliding board returns to the stop position. It will be done. Even when the sliding board returns to the stopped position, the circuit remains in a recording operation state and the electric motor remains in a rotating state. Therefore, as the sliding board returns to its stop position, the magnetic tape is rewinded or fast-forwarded, but the running motion of the magnetic tape is performed while lightly touching the magnetic head. Therefore, a recording operation is performed at high speed, and an operation to erase recorded information is performed. The present invention aims to provide a malfunction prevention device that solves these problems.

(d) Means for solving the problem The present invention includes an operating circuit that outputs a switching signal corresponding to each operation such as recording and playback, and a switching signal that is activated when the switching signal is output from the recording switching terminal of the operating circuit. A switch circuit that operates to switch the electric circuit from a playback state to a recording state, and a control switch that is switched by sliding displacement of a sliding board are provided, and the operation of the switch circuit is controlled by opening and closing operations of the control switch. This is what I did.

(E) Function The present invention opens and closes a control switch by utilizing the displacement movement of a sliding board that is displaced from a first position, which is a stop position, to a second position, which is a recording position, during recording operation, and also opens and closes the control switch. The switching operation of the electric circuit to the recording state and the operation of maintaining the recording state are performed only when the recording state is in the closed state.

(F) Embodiment The illustrated circuit is an embodiment of the malfunction prevention device of the present invention. In the diagram, 1 is an IC (integrated circuit)
This tape recorder circuit is made up of a switch circuit 2 for switching between a recording state and a playback state, a playback amplifier circuit 3, a recording amplifier circuit 4, and the like. Reference numeral 5 denotes an input terminal to which a recording signal from a microphone or the like is applied, and the recording signal applied to the input terminal 5 is configured to be input to the recording amplifier circuit 4. Reference numeral 6 denotes a recording/playback magnetic head which operates as a playback head in the playback state and as a recording head in the recording state by the switching operation of the switch circuit 2, and 7 a playback head amplified by the playback amplifier circuit 3. An output terminal to which a signal is output; 8 is a variable resistor to which the reproduced signal output to the output terminal 7 is applied and adjusts the level of the signal; 9 is a variable resistor whose level is adjusted by the variable resistor 8; A main amplifier circuit 9 receives a signal and amplifies the signal; 10 is the main amplifier circuit 9;
This is a speaker to which a signal amplified by a speaker is applied and which emits sound. 11 is a control terminal for controlling the operation of the switch circuit 2;
The tape recorder circuit 1 is configured to be in a recording state while a (high) level signal is applied. 12, 13, 14, 15 and 16 are
Operation switches 17 for stop, fast-forward, rewind, playback, and recording, respectively; 17 is an operation circuit that outputs a signal corresponding to each operation and maintains the state when each of the operation switches is pressed; There is a first terminal 18 that outputs a switching signal when the playback operation switch 15 is operated, a second terminal 19 that outputs an L (low) level switching signal when the recording operation switch 16 is operated, and a fast forward terminal. A third terminal 20 outputs a drive signal when the operation switch 13, rewind operation switch 14, or reproduction operation switch 15 is operated, and a fourth terminal outputs a reversal signal when the rewind operation switch 14 is operated. It is equipped with 21. Reference numeral 22 denotes a motor drive circuit that becomes operational when a drive signal is output from the third terminal 20 and rotates the motor 23;
It is constructed so that when a reversal signal from the terminal 21 is applied, the rotational direction of the motor 23 is reversed. 24 becomes operational when a switching signal is applied from the first terminal 18, and uses the rotational force of the electric motor 23 to move the sliding board on which the recording/playback magnetic head 6 is attached to a first position, which is a stopping position. This is a switching circuit that shifts the recording (playback) position to the second position. 25 is a control switch that is open when the sliding board is in the first position and closed when it is in the second position, and has a first terminal connected to the control terminal 11 of the tape recorder circuit 1; 25a and a second terminal 25b. 26 is a switching transistor whose emitter is connected to the power supply and whose collector is connected to the second terminal 25b of the control switch 25 via a resistor 27; its base is connected to the operating circuit 17 via the resistor 27; It is connected to the second terminal 19 of. In this embodiment, explanations of the erase head, bias oscillation circuit, etc., which become operational and perform the erase operation when in the recording state, are omitted. In addition, the tape recorder according to the present invention is designed so that the magnetic head lightly contacts the magnetic tape when it is in a stopped state, and fully contacts it when it is in a recording or playback state, and when the electric motor 23 rotates when it is in a stopped state, it can fast forward or The rewinding operation is configured to be performed.

The malfunction prevention device of the present invention is constructed as described above, and its operation will be explained next. When the user presses the fast-forward operating switch 13, the operating circuit 17 becomes operational and outputs a drive signal to the third terminal 20. When a drive signal is output to the third terminal 20, the motor drive circuit 22 to which the signal is applied becomes operational, and rotates the motor 23 connected as a load. As a result, the take-up reel shaft is driven to rotate at high speed by the rotational force of the electric motor 23, and the tape recorder performs a fast forward operation. Further, when the user operates the rewind operation switch 14, the operation circuit 17 is activated, and a drive signal and a reversal signal are output to the third terminal 20 and the fourth terminal 21, respectively. As a result, electric motor 2
3 is rotated in the opposite direction to that during the fast forward operation, and the tape recorder is rewinded. As described above, fast-forwarding and rewinding operations are performed, but in such a state, the magnetic tape is in light contact with the recording/playback magnetic head 6, so if the amplifier circuit is activated, a squealing sound can be heard. Therefore, the same operation as the so-called queue and review operation can be performed. Further, if the stop operation switch 12 is operated in the fast forward or rewind state, the operation circuit 17 becomes inactive, and the drive signal and inversion signal output to the third terminal 20 and the fourth terminal 21 disappear. Therefore, the motor drive circuit 22 becomes inactive and the motor 23 stops rotating, so that the tape recorder comes to a halt.

The fast-forwarding and rewinding operations are performed as described above, but the reproducing operation will now be explained. When the reproduction operation switch 15 is operated, the operation circuit 17 is put into operation, and a switching signal is output to the first terminal 18 and a drive signal is output to the third terminal 20. When a drive signal is output to the third terminal 20, the electric motor 23 starts rotating, and the switching circuit 24 is activated by the switching signal from the first terminal 18. When the switching circuit 24 is activated, a mechanism for displacing the sliding board from the first position to the second position is operated, and the sliding board is displaced to the second position by the rotational force of the electric motor 23. When the sliding board is moved to the second position, the recording/reproducing magnetic head 6 mounted on the sliding board is positioned in sufficient contact with the magnetic tape, and the drive mechanism drives the magnetic tape at a constant speed. become a state.
Then, when the drive board is displaced to the second position, the control switch 25 is closed, but since the switching transistor 26 is in a non-conductive state, an H level signal is applied to the control terminal 11 of the tape recorder circuit 1. There isn't. Therefore, the switch circuit 2 constituting the tape recorder circuit 1 does not operate, and the tape recorder circuit 1 operates as a reproduction circuit. The signal reproduced by the recording/reproducing magnetic head 6 is sent to the reproduction amplifier circuit 3.
After being amplified, the signal is output to the output terminal 7. The reproduced signal outputted to the output terminal 7 is input into the main amplifier circuit 9 after its level is adjusted by a variable resistor 8 . The reproduced signal input to the main amplification circuit 9 is amplified and then applied to the speaker 10 to emit sound. Therefore, the user can listen to the reproduction signal from the magnetic tape. When the stop operation switch 12 is operated while the tape recorder is in the reproduction operation state, the operation circuit 17 becomes inactive, and the switching signal and drive signal output to the first terminal 18 and the third terminal 20 disappear. Therefore, the motor drive circuit 22 becomes inactive, the motor 23 stops rotating, and the switching circuit 24 becomes inactive, so the sliding board that was in the second position returns to the first position, which is the stop position. The tape recorder is returned to its sliding position, and the tape recorder comes to a halt.

Although the reproduction operation is performed as described above, the recording operation will be explained next. Such a recording operation is performed by simultaneously operating the recording operation switch 16 and the playback operation switch 15. When such an operation is performed, the operation circuit 17 becomes operational, and a switching signal is output to the first terminal 18 and the second terminal 19, and a drive signal is output to the third terminal 20. When the switching signal and the drive signal are output to the first terminal 18 and the third terminal 20, the sliding substrate is displaced to the second position as in the above-described reproduction operation, and the drive mechanism drives the magnetic tape at a constant speed. become a state. When an L level switching signal is output to the second terminal 19, the switching transistor 26 is biased and becomes conductive, and the tape recorder circuit 1 is controlled through the emitter-collector of the switching transistor 26 and the control switch 25. An H level signal is applied to the terminal 11. As a result, the switch circuit 2 constituting the tape recorder circuit 1 operates, and the tape recorder circuit 1 operates as a recording circuit. A recording signal from a microphone or the like applied to the input terminal 5 is input to a recording amplifier circuit 4, where it is amplified and then applied to a recording/playback magnetic head 6 along with a bias signal from a bias oscillation circuit (not shown). and recorded on magnetic tape. Although the recording operation is performed in this way, if the stop switch 12 is operated during the recording state, the operation circuit 17
becomes inactive, and the switching signal that was output to the first terminal 18 and the second terminal 19 and the third terminal 20
The drive signal that was being output to disappears. Therefore, the electric motor 23 stops rotating and the sliding board moves to the first position.
The tape recorder is slid back into position and comes to a halt.

As described above, the recording operation is performed. Next, a case will be explained in which the locking of the sliding board at the second position is released due to the tape recorder falling or the like during the recording state. When the sliding board is released from being locked in the second position, the sliding board is moved to the first position and the constant speed driving state of the drive mechanism is released. Even when such an operation is performed, the electric motor 23 remains in a rotating state, so that the magnetic tape is fast-forwarded while lightly contacting the recording/reproducing magnetic head 6. On the other hand, the tape recorder circuit 1, which is in the recording state, switches the control switch 2 as the sliding board moves to the first position.
By opening 5, the H applied to the control terminal 11
Since the level signal disappears, the state is switched to the reproduction state. Therefore, even if the magnetic tape is fast-forwarded while lightly touching the recording/reproducing magnetic head 6, recording will not occur at high speed and no problem will occur.

Furthermore, in this embodiment, a case has been described in which a fast-forward operation is performed when the sliding board is displaced to the first position from the recording state, but it is of course possible to implement this in a tape recorder configured to perform a rewind operation. In such a case, the previously recorded signal will not be erased, which is an even greater advantage.

(g) Effects of the invention The malfunction prevention device of the invention is constructed so that when the magnetic head is in a stopped state, the magnetic head and the magnetic tape are in contact with each other, and the recording/playback switching operation of the tape recorder circuit is performed electronically. It is possible to prevent accidental erroneous recording or erroneous erasure, which was the problem with conventional tape recorders, and its practical value is very great.

[Brief explanation of drawings]

The illustrated circuit is an embodiment of the malfunction prevention device of the present invention. Explanation of main drawing numbers, 1... Tape recorder circuit, 2... Switch circuit, 3... Playback amplifier circuit, 4... Recording amplifier circuit, 6... Magnetic head for both recording and playback, 11... Control terminal. , 17...operation circuit, 22...motor drive circuit, 24...switching circuit, 25...control switch.

Claims (1)

[Scope of utility model registration request] A sliding substrate is provided, the magnetic head being in a first position where the magnetic head lightly contacts the magnetic tape when in a stopped state, and displaced to a second position where the magnetic head is fully contacting the magnetic tape during recording and playback operations; and a cassette tape recorder configured to electronically switch an amplifier circuit between a recording state and a playback state, an operation circuit that outputs a switching signal according to each operation such as recording and playback, and a recording switch of the operation circuit. A switch circuit that operates to switch when a switching signal is output from a terminal and switches the electric circuit from a playback state to a recording state, and a switch circuit that is open when the sliding board is in a first position and closed when it is in a second position. A control switch for preventing malfunction of a cassette type tape recorder, characterized in that the switch circuit is capable of switching an electric circuit to a recording state and maintaining the recording state only when the control switch is in a closed state. Device.