JPH04157651A - Motor controller for tape recorder - Google Patents

Abstract

PURPOSE:To accurately switch an operation of a tape recorder by waveform shaping a drive signal supplied from a motor driver to an armature winding into a pulse signal, counting the number of pulses, and setting normal and reverse rotating times of the motor. CONSTITUTION:A motor driver 12, a waveform shaper 17 for shaping a drive signal pulse signal output from the driver 12, a counter 18 inputting the pulse signal to be output from the shaper 17 and counting the number of pulses, and an operation controller 5 for controlling the operation of the driver 12 are provided. The drive signal supplied from the driver 12 to an armature winding is waveform shaped into a pulse signal, and the number of the pulse signals is counted to set forward and reverse rotating times of the motor. Thus, accurate rotating speed of the motor required to switch the operation of a tape recorder is obtained, and switching of the operation of the recorder can be effectively performed.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a tape recorder configured to switch operations using the rotational force of an electric motor, and particularly to a motor control circuit.

(b) Conventional technology Switching the operation of a tape recorder was done by using the pressing force on the operation button or the suction force of the plunger, but recently, the operation switching is done by using the rotational force of the electric motor. is often seen. Mechanisms that use the rotational force of an electric motor to switch operations are generally configured to control the meshing operation between a switching gear and a drive gear, in which a cam or the like for switching operations is formed. The operation of starting meshing between the switching gear and the driving gear is often performed using the suction force of a plunger. ,
The structure was complicated and the number of parts increased, so it was not suitable for downsizing tape recorders. As a technology that improves this point, there is a technology that switches the operation of a tape recorder by controlling the rotation direction of the electric motor.
There is one disclosed in Japanese Patent No. -298557.

(c) Problems to be Solved by the Invention Tape recorders that use the forward and reverse rotations of an electric motor to switch operations require setting the forward and reverse operation times; The time is set by a timer circuit. The electric motor that can be used for such operation switching is also used as the electric motor that drives the magnetic tape to run, so it is set by a timer circuit to account for fluctuations in negative force caused by differences in the running position of the magnetic tape. The rotational speed of the electric motor during the same period of time will change. Therefore, there is a problem that operation switching of the tape recorder cannot be performed accurately. The present invention aims to provide a motor control circuit that solves this problem.

(d) Means for Solving the Problems The motor control circuit of the present invention includes a motor drive circuit that supplies a drive signal to a military aircraft winding wire provided in the motor, and a drive signal output from the motor drive circuit. A waveform shaping circuit that shapes the pulse signal into a pulse signal, a counter circuit that receives the pulse signal output from the waveform shaping circuit and counts the number of pulses, and drives the motor based on the count value output from the counter circuit. It is composed of an operation control circuit that controls the operation of the circuit.

(E) Function The present invention sets the normal rotation and reverse rotation operation times of the motor by shaping the drive signal supplied from the motor drive circuit to the military aircraft thousand windings into pulse signals and counting the number of pulse signals. It was designed to do so.

(v) Embodiment The illustrated circuit is an embodiment of the motor control circuit of the present invention. In the same figure, (1), (2), (3)
and (4) are operating switches for playback, fast forwarding, rewinding, and stopping that are pressed and closed during playback, fast forwarding, rewinding, and stopping operations, and are self-returning switches that are opened when the pressing operation force is cut off. Consists of a switch. (5) is each operation switch (1), (2), (3) and <4)
This is an operation control circuit that controls the operation of the tape recorder in response to the pressing and closing operation, and includes a motor control signal output terminal (6) that outputs a signal that controls the operation of the electric motor, and a signal that controls the rotation direction of the electric motor. A rotation direction setting signal output terminal (7) is provided. (8> is a motor that drives the running of the magnetic tape and switches the operation of the tape recorder, and the armature winding (9), <10), (
11) is incorporated. (12) is a motor control signal output terminal (6) provided in the operation control circuit (5).
) and a rotational direction setting signal output terminal (7>), the motor drive circuit rotates the electric motor (8) based on signals output from the armature winding (9), (1).
Drive signal output terminals (13), (14), (15) that supply sinusoidal drive signals to 0), (11).
It is equipped with (16) is the motor drive circuit (12)
A signal amplification circuit (17) receives the drive signal output from the drive signal output terminal (15) provided at the drive signal output terminal (15) and amplifies the signal together with the signal amplification circuit (17). This is a waveform shaping circuit that receives an input signal and shapes the signal into a pulse signal. (18) is a counter circuit that receives the pulse signal output from the waveform shaping circuit (17) and counts the number of pulses, and each of the operation switches <1), (2
), (3) and (4) are closed, the count value is reset by the reset signal applied to the reset terminal (19), and the operation control circuit 5
) is configured to output a switching signal to the output terminal (20) when the count value reaches a value set by the output terminal (20). In such a circuit configuration, the count value set in the counter circuit (18) by the operation control circuit (5) is
Electric motor (8) required to rotate the switching gear that constitutes the operation switching mechanism of the tape recorder to a predetermined position.
In order to obtain the number of rotations of the armature winding (9), (10
> , (11) is set based on the wave number of the sinusoidal drive signal supplied. That is, the counter circuit (18
The number of pulses counted by ) corresponds to the wave number of the drive signal output to the drive signal output terminal (15) of the motor drive circuit (12). The number of rotations can be set. Therefore, the rotation speed and rotation direction of the switching gear constituting the operation switching mechanism of the tape recorder are set by the operation control circuit (5). The present invention is constructed as described above, and its operation will be explained next.

As a switching mechanism to the reproducing operating state, the sliding substrate on which the magnetic head is attached is displaced to the operating position by rotating the switching gear due to the rotating operation of the electric motor in the reverse direction, and then the electric motor is rotated in the forward direction. A case will be described in which the present invention is applied to a tape recorder configured to drive a magnetic tape. In the tape recorder configured as described above, when the user performs a playback operation, the playback operation switch (1) is pressed to close. When the regeneration operation switch 1) is pressed and closed, the counter circuit (18) is reset by a reset signal output from the operation control circuit (5), and the count value of the counter circuit (18) is It is set in accordance with the number of rotations of the electric motor (8) required to displace the motor (8) to the operating position. Further, an H (high) level control signal for rotating the electric motor (8) is output from a motor control signal output terminal (6) provided in the operation control circuit (5), and a rotation direction setting signal output terminal At (7), an H level signal for rotating the electric motor (8) in the opposite direction is output. When such a signal is output from the operation control circuit (5), the motor drive circuit (12) becomes operational,
Drive signal output terminals (13), (14), (15
) outputs a sinusoidal drive signal for rotating the electric motor (8) in the opposite direction. When such a drive signal is supplied to the armature windings (9), (10), and (11), the rotor incorporated in the electric motor (8) is rotated in the opposite direction, and the rotational force causes the switching gear to rotate. is rotationally driven to move the sliding substrate to the operating position. When such an operation is being performed, the drive signal output from the drive signal output terminal (15) of the motor drive circuit (12) is input to the signal amplification circuit (16), amplified, and then sent to the waveform shaping circuit. <17> is input. The drive signal input to the waveform shaping circuit (17) is waveform-shaped into a pulse signal and then input to the counter circuit (18), where the number of pulses is counted. Counter circuit (18)
When the count number reaches the value set by the operation control circuit (5), a switching signal is output to the output terminal (20). Output terminal (20) of the counter circuit (18)
When the switching signal is output to the 0 rotation direction setting signal output terminal (7), the output signal of the rotation direction setting signal output terminal (7) provided in the operation control circuit (5) is inverted from H level to L level. ) becomes L level, the drive signal output terminal (13) provided in the motor drive circuit (12)
), <14>.

(15) outputs a drive signal for rotating the electric motor (8) in the forward direction. The time when the electric motor (8) is reversed from the reverse direction to the forward direction is when the displacement operation of the sliding board to the operating position by the switching gear is completed, and thereafter the electric motor (8) is reversed from the reverse direction to the forward direction. The rotating operation brings the drive operation for reproducing the magnetic tape into a state where the reproducing operation state of the tape recorder is established.

Although the switching operation to the playback operation state is performed as described above,
Next, the operation when the stop operation is performed from the reproduction operation state will be explained. If a stop operation is performed while in the regeneration operation state, the stop operation switch 4) is pressed and closed.

When the stop operation switch (4) is pressed and closed, the counter circuit (18) is reset by a reset signal output from the operation control circuit (5), and the count value of the counter circuit (18) is The setting corresponds to the number of rotations of the electric motor*(8) required to return the motor from the operating position to the non-operating position. Further, when such a stop operation is performed, the output signal of the rotation direction setting signal output terminal (7) provided in the operation control circuit (5) is inverted from the L level to the H level. When the output signal of the rotation direction setting signal output terminal (7) becomes H level, the motor drive circuit (
a drive signal output terminal (13) provided in 12);
A drive signal for rotating the electric motor (8) in the opposite direction is output from (14) and (15).

Such drive signals are applied to the armature windings (9), (10),
(11) causes the rotor incorporated in the electric motor (8) to rotate in the opposite direction, and the rotational force drives the switching gear to return the sliding board to its non-operating position. It is done. While such an operation is being performed, a pulse signal output from the waveform shaping circuit (17) based on the drive signal output from the drive signal output terminal <15> of the motor drive circuit (12) is transmitted to the counter circuit ( 18). The number counted by the counter circuit (18) is determined by the operation control circuit (5).
When the preset value is reached, a switching signal is output to the output terminal (20). When the switching signal is output to the output terminal (20) of the counter circuit (18), the motor control signal output terminal (6) provided in the operation control circuit (5)
The output signal of is inverted from H level to L level. When the output signal of the motor control signal output terminal 6) becomes L level, the motor drive circuit (12) becomes inactive, and the motor (
8) stops rotating. When the switching signal is output to the output terminal (20) of the counter circuit (18), it is the time when the operation of returning the sliding board to the non-operating position by the switching gear is completed, and the rotation of the electric motor (8) is stopped. This means that the tape recorder has been switched from the playback operating state to the stop state.

As described above, the switching operation to the reproducing operating state and the switching operation from the reproducing operating state to the stop state are performed, but the rotation control operation of the electric motor (8) for switching to the fast forward operating state and the rewinding operating state is performed. can be performed in the same way, so the explanation thereof will be omitted.

()) Effects of the Invention The motor control circuit of the present invention controls the normal rotation of the motor by shaping the drive signal supplied from the motor drive circuit to the armature winding into a pulse signal and counting the number of pulse signals. Since the reverse operation time and reverse operation time are set, it has the advantage of being able to obtain the accurate rotational speed of the electric motor required for switching the operation of the tape recorder.
The present invention has the advantage that it is possible to reliably switch the operation of a tape recorder.

[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)... Operation switch for playback, (2)... Operation switch for fast forwarding, (3)... Operation switch for rewinding, (4)... Operation switch for stopping. , (5)...
Operation control circuit, (8)... electric motor, (9),
(10), (11)...armature winding, (12)
...Electric motor drive circuit, (13), (14). (15>... Drive signal output terminal, (17)... Waveform shaping circuit, (18)... Counter circuit.

Claims (1)

[Claims] (1) In a tape recorder configured to switch operations using the rotational force of an electric motor, a motor drive circuit that supplies a drive signal to an armature winding provided in the electric motor, and a A waveform shaping circuit that shapes the output drive signal into a pulse signal, a counter circuit that receives the pulse signal output from the waveform shaping circuit and counts the number of pulses, and a switching signal that is output from the counter circuit. an operation control circuit that controls the operation of the motor drive circuit based on the above, and sets forward and reverse rotation operation times of the motor based on the count value of the counter circuit. Electric motor control circuit.