JPH0316105Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a motor control circuit for a tape recorder in which a first tape recorder having at least a playback function and a second tape recorder having both recording and playback functions are integrally incorporated. .

Recently, tape recorders with two integrated tape recorders as described above have become popular, but in such tape recorders, the signal played by the first tape recorder is recorded by the second tape recorder. It has a function called dubbing. In terms of operability, such a tape recorder having a dubbing function is required to have a function of simultaneously starting the playback operation of the first tape recorder and the recording operation of the second tape recorder.

The present invention has been developed in view of these points, and will be described in detail below with reference to the illustrated embodiments. In the figure, 1 is a first electric motor that drives the magnetic tape of a first tape recorder equipped with at least a playback function, 2 is a first driving transistor to which the first electric motor 1 is connected as a collector load, and The emitter is connected to a power source, and the base is connected to the power source via a resistor 3. 4 is a second unit with recording and playback functions.
A second electric motor 5 drives the magnetic tape of the tape recorder, and 5 is a second driving transistor to which the second electric motor 4 is connected as a collector load, the emitter of which is connected to a power supply, and the base of which is connected to a resistor 6. Connected to power via. 7 is a first switch that is closed when a playback operation of the first tape recorder is performed, and a first switch 7a that is grounded and a first bias resistor 8
The second contact piece 7b is connected to the base of the first driving transistor 2 via the second contact piece 7b.
Reference numeral 9 denotes a selection switch for switching between simultaneous operation and non-operation of the first tape recorder and the second tape recorder, and is connected to a grounded first terminal 9a and a second contact piece 7b of the first switch 7. .
It includes a second terminal 9b and a common terminal 9c. 1
0 is a second switch that is closed when the second tape recorder performs a recording or playback operation, and connects a first contact piece 10a and a second bias resistor 11 connected to the common terminal 9c of the selection switch 9. The second contact piece 10b is connected to the base of the second driving transistor 5 via the second contact piece 10b.

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 selection switch 9 is in the state shown in the figure, that is, in the first
A case will be described in which the tape recorder and the second tape recorder do not start operating at the same time. When the first tape recorder and the second tape recorder are in a stopped state, the first switch 7 and the second switch 10 are in an open state, so that both the first driving transistor 2 and the second driving transistor 5 are in a non-conducting state. be. When the first tape recorder is operated for reproduction in such a state, the drive mechanism enters the reproduction state and the first switch 7 is closed. When the first switch 7 is closed, the first driving transistor 2
The base potential of the first driving transistor 2 drops, and the first driving transistor 2 becomes forward biased. As a result, the first
The driving transistor 2 is turned on and the first electric motor 1 connected as a collector load is driven to rotate. Therefore, the magnetic tape is driven to travel by the first electric motor 1, and the reproduction operation state of the first tape recorder is established. The reproduction operation of the first tape recorder is performed in this manner, and next, the reproduction operation of the second tape recorder will be explained. When the second tape recorder is operated for reproduction, the drive mechanism enters the reproduction state and the second switch 10 is closed. When the second switch 10 is closed, the second drive transistor 5 is activated by the second switch 10 and the selection switch 9.
Since the base potential of the second driving transistor 5 is lowered, the second driving transistor 5 is inverted to a conductive state. As a result, the second electric motor 4 is driven to rotate and drive the magnetic tape to run, thereby establishing a reproducing operating state of the second tape recorder. Also, the second
When a recording operation is performed on the tape recorder, the second switch 10 is closed, and a magnetic tape drive mechanism similar to that used during playback is established, and the electric circuit is switched to a recording state, thereby establishing a recording operation state.

As described above, operations are carried out when the first tape recorder and the second tape recorder are operated independently.Next, the signal reproduced by the first tape recorder is recorded by the second tape recorder. The dubbing operation will be explained. Such a dubbing operation is performed by switching the selection switch 9 to the opposite side from the state shown in the figure, then performing a recording operation on the second tape recorder, and then performing a reproduction operation on the first tape recorder. If the second tape recorder is operated to record when the selection switch 9 is in the opposite position from the state shown in the figure, the electric circuit and drive mechanism are brought into the recording state and the second switch 10 is closed. Since the base potential of the second driving transistor 5 does not drop, the second driving transistor 5 is in a non-conductive state. Therefore, the recording operation of the second tape recorder is not started, and the second tape recorder is in a recording standby state. When the first tape recorder is operated for reproduction in such a state, the drive mechanism enters the reproduction state and the first switch 7 is closed. When the first switch 7 is closed, the first drive transistor 2 becomes conductive and rotates the first motor 1 as described above, and as a result, the regeneration operation of the first transistor is started. 7, the base potential of the second driving transistor 5 drops, so that the first driving transistor 5 is inverted to a conductive state. As a result, the second electric motor 4 is rotationally driven,
Since the recording operation of the second tape recorder that has been in the recording standby state is started, a state is established in which the signal reproduced by the first tape recorder is recorded by the second tape recorder, that is, a dubbing state. By performing the playback operation of the first tape recorder in this way, the recording operation of the second tape recorder can be started simultaneously with the playback operation of the first tape recorder, so that the dubbing operation can be easily performed.

In this embodiment, the first switch 7 and the second switch 7 are closed by the playback operation of the first tape recorder.
Although the second switch 10, which is closed by the recording or playback operation of the tape recorder, is configured as a mechanical switch, it can also be configured using a switching element such as a transistor.

As explained above, the motor control circuit of the present invention can simultaneously start the playback operation of the first tape recorder and the recording operation of the second tape recorder by the playback operation of the first tape recorder, which improves operability. The practical value of the present invention is very high.

[Brief explanation of drawings]

The illustrated circuit is one embodiment of the motor control circuit of the present invention. Explanation of main drawing numbers, 1...First motor, 2...First drive transistor, 4...Second motor, 5
...Second driving transistor, 7...First switch, 9...Selection switch, 10...Second switch.

Claims (1)

[Scope of utility model registration request] In a tape recorder incorporating at least a first tape recorder with a playback function and a second tape recorder with a recording and playback function, a first switch that is closed when the first tape recorder is in a playback state; A second tape recorder that is closed when the second tape recorder is in the recording or playback state.
a first electric motor that drives the magnetic tape of the first tape recorder; a first drive transistor that becomes electrically conductive when the first switch is closed and drives the first electric motor; Simultaneous operation of a second electric motor that drives the magnetic tape to run, a second driving transistor that becomes conductive when the second switch is closed and drives the second electric motor, and a first tape recorder and a second tape recorder. and a selection switch for switching between inactivation and non-operation, and when the selection switch is in the simultaneous operation position, the selection switch and the second switch control the base bias circuit of the first driving transistor and the base bias of the second driving transistor. A motor control circuit for a tape recorder, characterized in that the motor control circuit is connected to a circuit.