JPH0248990Y2 - - Google Patents

Description

[Detailed explanation of the invention] (a) Industrial application field The present invention relates to a tape recorder, especially the first one.
The present invention relates to a motor control circuit for a tape recorder in which a tape recorder and a second tape recorder are incorporated.

(b) Prior Art Recently, so-called double tape recorders, in which two tape recorders are built into the same device, have become popular. Some of these tape recorders include a dubbing operation in which a signal reproduced by a first tape recorder is recorded in a second tape recorder, and when the reproduction operation of one tape recorder is completed, the reproduction operation of the other tape recorder is started. Some devices are configured to perform continuous playback operations. In addition, portable tape recorders such as tape recorders with radios are constructed so that power is supplied to the electric motor through a switch that is closed by pressing a playback operation button, etc., and is called a tape deck. The tape recorder is equipped with a power switch that supplies power to the electric motor, etc., regardless of the operation button used to switch the operation of the tape recorder. In addition, some recent tape recorders have a mechanism called a soft mechanism that uses the rotational force of an electric motor to displace the sliding board on which the magnetic head is mounted to the operating position and from the operating position to the non-operating position. Some devices are configured to switch operations based on. In a tape deck incorporating such a soft mechanism, when the power switch is opened during playback operation, the power supply to the motor is cut off and the motor stops rotating. In such a state, when the stop operation is performed, the regeneration operation button that has been locked in the operating position is returned to the non-operating position, but the sliding board in the operating position is returned to the non-operating position because the motor does not rotate. You won't be disappointed. When the power switch is turned on in such a state, power is supplied to the electric motor and it rotates, and the rotational force returns the sliding board to the non-operating position. In some tape recorders, the operation of the electric motor is controlled, and there is a problem in such tape recorders that even though the power switch is turned on, the electric motor does not rotate and the sliding board cannot be returned to the non-operating position.

(C) Purpose of the invention The present invention is based on a sliding board on which a magnetic head is mounted, which is configured to be moved to an operating position by the rotational force of an electric motor, and also to be displaced from an operating position to a non-operating position. The present invention aims to provide a motor control circuit suitable for a tape recorder incorporating a first and second tape recorder and having a continuous playback function.

(d) Structure of the invention The present invention provides a first control switch that is closed when the playback operation button of the first tape recorder is locked in the operating position, and a first control switch that is closed when the playback operation button of the second tape recorder is locked in the operating position. A second control switch is provided which is closed when the first control switch is locked;
First and second NAND circuits are provided, in which an H level signal is input to one input terminal when the control switch and the second control switch are closed, and the other input terminal is connected to the other output terminal. ,
The operation of electric motors built into the first tape recorder and the second tape recorder is controlled by the output signals of the first NAND circuit and the second NAND circuit.

(E) Embodiment The illustrated circuit is an embodiment of the motor control circuit of the present invention. In the figure, reference numeral 1 denotes a first electric motor that drives the magnetic tape of the first tape recorder, and as the playback operation button is pressed, the sliding board on which the magnetic head is mounted is displaced to the operating position. It has the effect of displacing the sliding board to a non-operating position by returning the regeneration operation button in conjunction with the stop operation. Reference numeral 2 denotes a second electric motor that drives the magnetic tape of the second tape recorder, and when the playback operation button is pressed, the sliding board on which the magnetic head is mounted is moved to the operating position, and at the same time, it is also operated to stop the magnetic tape. The accompanying return of the regeneration operation button has the effect of displacing the sliding board to the non-operating position. 3 is a first motor drive circuit that rotationally drives the first motor 1, and the first motor 1 controls the operation of a first drive transistor 4 whose collector is connected as a load and the first drive transistor 4. It is composed of a first control transistor 5. Reference numeral 6 denotes a second motor drive circuit that rotationally drives the second motor 2, and a second drive transistor 7 whose collector is connected as a load to the second motor 2;
The second control transistor 8 controls the operation of the second control transistor 8. 9 and 10 are the first and second
It is a NAND circuit, and one of its input terminals is connected to the output terminal of the other NAND circuit, and its output terminals are connected to the bases of the second control transistor 8 and the first control transistor 5, respectively. Reference numeral 11 denotes a first control switch that is closed when the playback operation button of the first tape recorder is in the operating position, and when it is in the closed state, an H (high) level signal is sent to the input terminal of the first NAND circuit 9. is connected so as to apply 1
2 is a second control switch that is closed when the playback operation button of the second tape recorder is in the operating position; when in the closed state, the second NAND circuit 10 is closed;
is connected to apply an H level signal to the input terminal of the input terminal. Reference numerals 13 and 14 indicate first and second selection switches for selecting whether or not to perform continuous playback operations of the first tape recorder and the second tape recorder, and when in the non-operating position shown, the first NAND circuit 9 and is connected to ground the input terminal of the second NAND circuit 10. 20
1 is a power supply connection terminal connected to a commercial power source; 16 is a power switch; 17 converts the AC power supplied by closing the power switch 16 into a predetermined DC voltage, and supplies DC voltage to each circuit of the tape recorder; This is a power supply circuit. 15 is the above-mentioned number
This is a capacitor connected between the input terminal of the 2NAND circuit 10 and the ground, and has the function of giving priority to the reproduction operation of the first tape recorder when the first control switch 11 and the second control switch 12 are closed at the same time. It is something.

The motor control circuit of the present invention is constructed as described above, and the operation of this circuit will now be described. First, the case where the first selection switch 13 and the second selection switch 14 are in the non-operating position shown in the figure will be described. When the power switch 16 is closed in this state, AC power is input to the power supply circuit 17 through the switch 16, and the power supply circuit 17
A predetermined DC voltage is supplied to each circuit. In such a state, the first selection switch 13 and the second selection switch 14 select the first NAND circuit 9 and the second selection switch 14.
The level of one input terminal of the 2NAND circuit 10 is L
(low) level.
The output terminals of the 1NAND circuit 9 and the second NAND circuit 10 are in a state where H level signals are output.
When the power switch 16 is closed in this way, the
An H level signal is output to the output terminals of the 1NAND circuit 9 and the second NAND circuit 10, and the H level signal is applied to the bases of the second control transistor 8 and the first control transistor 5, respectively. As a result, the first control transistor 5 and the second control transistor 8 are rendered conductive, causing the first drive transistor 4 and the second drive transistor 7 to be rendered conductive. When the first drive transistor 4 and the second drive transistor 7 are turned on, the first electric motor 1 and the second electric motor 2, which are connected as loads to their respective collectors, are driven to rotate. Therefore,
In such a state, each operation of the first tape recorder and the second tape recorder can be performed independently. Further, when the playback operation buttons are pressed to perform the playback operation of the first tape recorder and the second tape recorder, each operation button is locked in the operating position and the first control switch 11 is pressed.
and the second control switch 12 is closed, but the second control switch 12 is closed.
The input terminals of the 1NAND circuit 9 and the 2nd NAND circuit 10 are connected to the first selection switch 13 which is in the non-operating position.
Since it is held at L level by the second selection switch 14, the first NAND circuit 9 and the second selection switch 14
The level of the output signal of the 2NAND circuit 10 is never inverted. Also, the first tape recorder and the second
When a tape recorder is operated for reproduction, a switching mechanism built into each tape recorder is operated by the rotational force of the first electric motor 1 and second electric motor 2, and the sliding board on which the magnetic head is mounted is operated. The playback operation state of each tape recorder is configured by displacing the tape recorder to its position. When a stop operation is performed while each tape recorder is in the playback operation state, the lock at the operating position of each playback operation button is released, and each sliding board is moved by the rotational force of the first electric motor 1 and the second electric motor 2. It is returned to the non-operating position.

As described above, the operation is performed when the first selection switch 13 and the second selection switch 14 are in the non-operating position, but next, when the selection switches 13 and 14 are in the operating position opposite to the state shown in the figure, I will explain about it. When the first tape recorder is operated for reproduction in such a state, the reproduction operation button is locked in the operating position and the first control switch 11 is closed. When the first control switch 11 is closed, the first NAND
An H level signal is applied to the input terminal of the circuit 9,
Since the two inputs of the first NAND circuit 9 both go to H level, the output signal of the first NAND circuit 9 goes to L level. When the output signal of the first NAND circuit 9 goes to the L level, the second control transistor 8 becomes non-conductive and the second drive transistor 7 is inverted to the non-conductive state, so that the second electric motor 2 stops rotating. When the first tape recorder is operated in this manner, the first tape recorder enters the playback operation state and the second electric motor 2 comes to a rotation stop state. When the second tape recorder is operated for reproduction while the first tape recorder is in the reproduction operation state, the reproduction operation button is locked in the operating position and the second control switch 12 is closed. When the second control switch 12 is closed, an H level signal is input to the input terminal of the second NAND circuit 10 through the switch 12, but the signal at the H level is input to the other input terminal.
Since the L level signal which is the output of the 1NAND circuit 9 is being input, the output of the second NAND circuit 10 is in the H level state, and the reproduction operation of the first tape recorder continues. In this way, when the first tape recorder is in the playback mode, the second tape recorder
When the tape recorder is operated for playback, the playback operation button of the second tape recorder is locked in the operating position, but since the second electric motor 2 is not driven to rotate, the second
The playback operation of the tape recorder is never started. When the first tape recorder starts playing and the magnetic tape reaches the end, the automatic stop device built into the first tape recorder causes the first tape recorder to return from the playing state to the stopped state. . When the first tape recorder returns to the stopped state, the first control switch 11 is opened and the level of the signal input to the first NAND circuit 9 becomes L level, so that the output signal of the first NAND circuit 9 is inverted to H level. Applicable number
When the output of the 1NAND circuit 9 becomes H level, the two inputs of the second NAND circuit 10 to which the signal is input both become H level, so the output of the second NAND circuit 10 becomes L level. As a result of this operation, the second control transistor 8 becomes conductive and drives the second electric motor 2 to rotate, and as the first control transistor 5 is reversed to the non-conductive state, the first control transistor 8 becomes conductive.
Electric motor 1 stops rotating. When the second electric motor 2 starts rotating, the switching mechanism incorporated in the second tape recorder is actuated by the rotational force of the second electric motor 2, and the sliding board on which the magnetic head is mounted is moved to the operating position. As a result, the reproduction operation of the second tape recorder is started. In this way, if the second tape recorder is operated while the first tape recorder is in the playback operation state, the second tape recorder goes into the playback standby state, and the first tape recorder
When the tape recorder is returned to the stopped state by a stop operation or an automatic stop device, the second tape recorder starts playing, and a so-called continuous playback operation is performed. In addition, if a playback operation is performed on the first tape recorder while the second tape recorder is in the playback mode, the first tape recorder will enter the playback standby state, and the second tape recorder will be stopped by the stop operation or automatic stop device. When the first tape recorder is restored, the reproduction operation of the first tape recorder is similarly started. As described above, when the second tape recorder is operated while the first tape recorder is in the playback state, and when the second tape recorder is in the playback state, the first
Although the operation is performed when the tape recorder is played back, the case where the playback operation on the first tape recorder and the playback operation on the second tape recorder are performed simultaneously will be described. When the playback operation button of the first tape recorder and the playback operation button of the second tape recorder are pressed simultaneously, the operation buttons are locked in the operating position and the first control switch 1 is pressed.
The first and second control switches 12 are closed. When the first control switch 11 is closed, an H level signal is immediately applied to one input terminal of the first NAND circuit 9 through the switch 11, but even when the second control switch 12 is closed, the second NAND circuit 1
Since the capacitor 15 is connected between the 0 input terminal and the ground, an H level signal is not immediately applied to the input terminal. As a result of this operation, the output of the first NAND circuit 9 becomes L level and the output of the second NAND circuit 10 becomes H level. Therefore, in such a state, the first tape recorder is in the playback operation state, and the second tape recorder is in the playback standby state. In this way, if the playback operation of the first tape recorder and the playback operation of the second tape recorder are performed simultaneously, the playback operation of the first tape recorder will take priority.

The continuous regeneration operation is performed as described above, but next, the operation when the power switch 16 is opened in the continuous regeneration operation state, a stop operation is performed, and then the power switch 16 is closed will be described. When the tape recorder is in continuous playback mode, for example, when the first tape recorder is in playback mode and the second tape recorder is in playback standby mode, if the power switch 16 is opened, the power supply from the power supply circuit 17 is cut off. The first electric motor 1 stops rotating. In such a state, each playback operation button of the first tape recorder and the second tape recorder is locked in the operating position, and when the user performs a stop operation in such a state, each playback operation button will be moved from the operating position. Returned to non-operating position. Since the first tape recorder is in the playback operation state, the sliding board is in the state of being displaced to the operating position, and when the stop operation is performed, the switching mechanism goes into the stop state, but the first electric motor 1 is in the rotation stop state. Therefore, the sliding substrate is not returned to the non-operating position. Further, since the second tape recorder is in a playback standby state, the sliding board is in a non-operating position, and when a stop operation is performed, the playback operation button returns to the non-operating position and the tape recorder is placed in a stopped state. When the first tape recorder and the second tape recorder are stopped in this way, each playback operation button is returned to the non-operating position and the first control switch 11 and second control switch 12 are opened. The sliding board of the tape recorder is in the operating position. When the power switch 16 is closed in this state, power is supplied from the power circuit 17 to each circuit. In such a state, the first control switch 11 and the second control switch 12 are open, and the first selection switch 13 and the second selection switch 14 are in an operating position opposite to the state shown, but in the operative position.
Since the signal levels of the input terminals of the 1NAND circuit 9 and the second NAND circuit 10 are brought to L level by the resistors 18 and 19, respectively, the first NAND circuit 9
And the output signal of the second NAND circuit 10 becomes H level. When the outputs of the first NAND circuit 9 and the second NAND circuit 10 go to H level, the second motor drive circuit 6 and the first motor drive circuit 3 become operational, driving the second motor 2 and the first motor 1 to rotate. When the first electric motor 1 is rotationally driven, the switching mechanism that has been in the operation standby state due to the above-mentioned stop operation is activated, and the rotational force of the first electric motor 1 causes the sliding board that was in the operation position to become inoperable. Slide it back into position. In this way, even if the power switch 16 is released in the continuous playback state and then the stop operation is performed and the playback operation buttons of each tape recorder are returned to the non-operating position, the power switch 16
When closed, the electric motor rotates and the sliding board can be returned to the non-operating position.

(f) Effects of the invention According to the motor control circuit of the invention, when the power switch is closed when the playback operation button is in the non-operating position, the motor is driven to rotate regardless of the state of the tape recorder. Therefore, even if the sliding board on which the magnetic head is mounted is in the operating position despite being stopped, when the power switch is closed, the rotation of the electric motor will cause the sliding board to return to the non-operating position. The present invention is ideal for use as a motor control circuit for a tape recorder in which operation is switched by the rotational force of the motor.

[Brief explanation of the drawing]

The illustrated circuit is one embodiment of the motor control circuit of the present invention. Explanation of main drawing numbers, 1...First motor, 2...Second motor, 3 ...First motor drive circuit, 6 ...Second motor drive circuit, 9...First NAND circuit, 10
...Second NAND circuit, 11...First control switch, 12...Second control switch, 13...First selection switch, 14...Second selection switch, 16...
...Power switch.

Claims (1)

[Scope of utility model registration request] The sliding board on which the magnetic head is placed is moved to the operating position by the rotational force of the electric motor, and is also displaced from the operating position to the non-operating position, and the playback operation button is locked in the operating position. A tape recorder incorporating first and second tape recorders configured as shown in FIG. 2. A second electric motor incorporated in the second tape recorder, a second electric motor drive circuit for rotationally driving the second electric motor, and a first control that is closed when a playback operation button of the first tape recorder is in an operating position. switch, a second control switch that is closed when the playback operation button of the second tape recorder is in the operating position, and when the first control switch and the second control switch are closed, one input terminal is
the first and second NAND circuits each receiving a level signal and having the other input terminal connected to the other output terminal;
circuit and the output signal of the second NAND circuit.
Controls the operation of the motor drive circuit and the first motor drive circuit, and drives the first motor and the second motor to rotate when power is supplied when the first control switch and the second control switch are in an open state. A motor control circuit for a tape recorder, characterized in that: