JPH0516656Y2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Industrial Application Field The present invention relates to a tape recorder, and particularly to a control circuit that controls operation switching using a timer device.

(b) Prior Art A tape recorder called a tape deck used in combination with a stereo device has functions such as recording when the user is away from home, alarm playback, etc. in cooperation with a timer device. Mechanisms for performing such timer control operations include a mechanical mechanism that releases the pause operation when power is supplied when the tape recorder is set in a pause state during recording or playback operation, and a mechanism that uses the suction force of a plunger to cancel the pause operation. There is an electric type that utilizes this to switch from a stopped state to each operating state, and an example of an electrical technique is disclosed in Japanese Utility Model Publication No. 1982-19247.

(c) Problems to be solved by the invention A tape recorder configured to electronically control operations using a timer is equipped with an operation circuit that switches operations in response to each input operation. The operating circuit is configured to be reset when a power supply operation is performed, and then receive a control signal for timer operation. Therefore, the control signal for performing the timer operation must be output for a predetermined period of time after the power is turned on, and a time constant circuit is provided to perform such an operation. In order to perform accurate timer operation, it is necessary to increase the time constant of the time constant circuit so that the control signal is output until the operation circuit is reset and is in a state of normal operation. Although the larger the time constant of such a time constant circuit, the more accurate the timer operation can be performed, the following problems arise. That is, even if a stop operation or the like is performed immediately after the timer operation has been performed, the time constant circuit remains in the operating state, so a control signal from the timer is input, and the operation switching is performed again. The present invention aims to provide a control circuit that is improved in this respect.

(d) Means for solving the problem The control circuit of the present invention has a playback switch that is switched by a playback operation, a recording switch that is switched by a recording operation, and control by switching between the playback switch and the recording switch. An operating circuit has a playback output terminal and a recording output terminal that output switching signals corresponding to each operation when a signal is input, a capacitor that is charged for a predetermined time when the power is turned on, and a timer that controls the recording and playback operations. a selection switch for making a selection, a switching transistor that becomes conductive while the capacitor is being charged and inputs a playback control signal and a recording control signal to the operation circuit via the selection switch, and the operation circuit. The charging transistor is configured to become conductive when a switching signal is output to the reproducing output terminal of the converter, and quickly charge the capacitor.

(E) Effect The present invention provides a charging transistor that becomes conductive when a switching signal is output to the regeneration output terminal of the operating circuit in response to a control signal input by a timer control operation. The capacitor provided to control the timer operation is quickly charged.

(F) Embodiment The illustrated circuit is an embodiment of the control circuit of the present invention. In the figure, 1, 2, and 3 are closed by operating the recording operation button, playback operation button, and stop operation button, respectively, and are opened when the operation force to each operation button is cut off. A self-returning recording switch, a playback switch, and a stop switch, each of which has first terminals 1a, 2a, and 3 that are grounded.
a and second terminals 1b, 2b, and 3b.
4 is a recording input terminal 5 connected to the second terminal 1b of the recording switch 1, and a playback switch 2.
This is an operating circuit having a playback input terminal 6 connected to the second terminal 2b of the stop switch 3 and a stop input terminal 7 connected to the second terminal 3b of the stop switch 3. When an L (low) level signal is input to the recording input terminal 5, it becomes H.
The recording output terminal 8 outputs a (high) level switching signal, and the playback output outputs an H level switching signal when an L level signal is input to the playback input terminal 6 by closing the playback switch 2. When the stop switch 3 is closed and an L level signal is input to the stop input terminal 7, the H level signal that was output to the recording output terminal 8 and the playback output terminal 9 is The signal is reset and goes low.
Configured to flip on level. The operation circuit 4 is also equipped with a reset circuit that resets the internal circuit when the power is turned on, and also has control functions using a fast forward switch, a rewind switch, and a pause switch. Explanation of the points has been omitted. 10 is the operation circuit 4
This is a regeneration switching circuit that becomes operational when an H level switching signal is output to the regeneration output terminal 9 provided in the regeneration output terminal 9, and has the function of bringing the drive mechanism etc. into the regeneration operation state. Reference numeral 11 denotes a recording switching circuit which becomes active when an H level switching signal is output to the recording output terminal 8 provided in the operating circuit 4, and has the function of switching the amplifier circuit etc. from the playback state to the recording state. have. Reference numeral 12 denotes a selection switch for selecting recording operation and playback operation by timer operation, which includes a playback side terminal 12p connected to the playback input terminal 6 of the operation circuit 4, an open non-operation terminal 12a, and a backflow prevention terminal. Diode 13,1
The recording side terminal 12r and the movable terminal 12b are connected to the reproduction input terminal 6 and the recording input terminal 5 via the recording terminal 4. 15 is a first switching transistor whose collector is connected to the movable terminal 12b of the selection switch 12 and whose emitter is grounded; 16 is a first switching transistor whose collector is connected to a resistor 17;
through the first switching transistor 1
5 and whose emitter is connected to the power supply, and whose base is grounded via a time constant circuit 20 consisting of a resistor 18 and a capacitor 19. The collector of 21 is a light emitting diode 22
A display transistor is connected to a power source via a resistor 23 and has an emitter grounded, and its base is connected via a resistor 24 to the reproduction output terminal 9 of the operating circuit 4.
25 is a charging transistor whose collector is connected to the charging terminal of the capacitor 19 constituting the time constant circuit 20 and whose emitter is connected to the power supply via a resistor 26; The display transistor 2
1 collector. In such a circuit configuration, the time constant of the time constant circuit 20 is the same as that of the operating circuit 4.
The reset circuit is set to be sufficiently longer than the time required for the reset circuit to operate normally after power is supplied to the reset circuit. Further, the value of the resistor 26 is set so that the charging operation of the capacitor 19 due to the conduction of the charging transistor 25 is quickly performed. The control circuit of the present invention is constructed as described above, and its operation will be explained next.

First, select switch 1 to select the timer operation.
2 is in the illustrated non-operating position, that is, the normal operation will be described. Power switch (not shown)
When closed, power is supplied to the amplifier circuit (not shown), etc., and power is also supplied to the operating circuit 4.
When power is supplied to the operating circuit 4, the operating circuit 4
The reset operation is performed by the function of a reset circuit built into the operating circuit 4, and the playback output terminal 9 and the recording output terminal 8 provided in the operation circuit 4.
A state is reached in which an L level signal is output. When the playback operation button is operated in such a state, the playback switch 2 is closed and an L level signal is input to the playback input terminal 6 provided in the operation circuit 4. When an L level signal is input to the playback input terminal 6, a logic circuit (not shown) and a switching circuit (not shown) built into the operation circuit 4 act to output the playback output terminal. An H level signal is output to the terminal 9. When an H level signal is output to the reproduction output terminal 9, the reproduction switching circuit 10
enters the operating state and causes the tape recorder to enter the playback operating state. Further, when an H level signal is output to the reproduction output terminal 9, a bias current is supplied to the base of the display transistor 21, and the display transistor 21 becomes conductive. When the display transistor 21 becomes conductive, the light emitting diode 22 connected to its collector as a load is driven to light up, and the light emitting diode 22
It is possible to recognize that the device is in the reproducing operation state by the lighting of the device. When a stop operation is performed in such a reproducing operation state, the stop switch 3 is closed by the stop operation button, and an L level signal is input to the stop input terminal 7. When an L level signal is input to the stop input terminal 7, the operating circuit 4 is reset and the H level signal outputted to the reproduction output terminal 9 is inverted to L level. As a result, the reproduction switching circuit 10 becomes inactive, the display transistor 21 becomes non-conductive, and the tape recorder becomes stopped. Although the playback operation is performed in this manner, the recording operation will be explained next. Such a recording operation is performed by operating the playback operation button while operating the recording operation button. When such an operation is performed, an L signal is sent to the recording input terminal 5 of the operating circuit 4 by closing the recording switch 1.
When the reproduction switch 2 is closed, an L level signal is input to the reproduction input terminal 6. When an L level signal is input to the recording input terminal 5 and the reproduction input terminal 6, an H level signal is output to the recording output terminal 8 and the reproduction output terminal 9. When an H level signal is output to the recording output terminal 8, the recording switching circuit 11 becomes operational and switches the amplifier circuit etc. to a recording operation state. Further, when an H level signal is output to the playback output terminal 9, the playback switching circuit 10 goes into operation and the drive mechanism is put into operation, so that the tape recorder goes into the recording operation state. Then, when in such a recording operation state, the display transistor 21
is biased and becomes conductive, driving the light emitting diode 22 to light up, so that the light emitting diode 22 performs a display operation. If a stop operation is performed while in such a recording operation state, the operation circuit 4 is reset as described above, so that the tape recorder is returned to the stopped state.

Although the normal operation is performed as described above, the control operation by the timer device will be explained next. First, the timer operation for starting the playback operation at a set time will be explained. Such an operation is performed by operating the selection switch 12 to switch to the reproduction side terminal 12p and setting the timer device to a desired time. In this state, power is supplied to the tape recorder through the timer device at the set time. When power is supplied to the tape recorder, power is supplied to the operating circuit 4 and the amplifier circuit, and a charging current flows to the capacitor 19 between the emitter and base of the second switching transistor 16 and through the resistor 18. As a result, the second switching transistor 1
6 is biased and becomes conductive, and the second
A bias current is supplied to the base of the first switching transistor 15 between the emitter and collector of the switching transistor 16 and through the resistor 17, so that the first switching transistor 15 becomes conductive. The first switching transistor 15 and the second switching transistor 16 are kept conductive for a time set by the time constant circuit 20 , but during that time the reset operation of the operation circuit 4 is not performed. It is set to be sufficiently longer than the time required to reach a steady operating state. Therefore, when the operating circuit 4 is reset to a normal operating state, the reproducing input terminal 6 is grounded by the selection switch 12 and the first switching transistor 15, so that the reproducing input terminal 6 is not connected to the reproducing input terminal 6. An L level signal will be input. As a result, an H level switching signal is output to the playback output terminal 9 of the operation circuit 4, and as described above, the playback switching circuit 10 becomes operational, configuring the playback operation state of the tape recorder, and the display transistor The light emitting diode 22 is driven to light by the conduction of the light emitting diode 21. Further, when the display transistor 21 becomes conductive, the charging transistor 25 is biased and reversed to the conductive state, and a capacitor 19 constituting the time constant circuit 20 is connected to the resistor 26 and between the emitter and collector of the charging transistor 25. Charging current is supplied. As a result, the charging operation of the capacitor 19 is quickly performed, and when the charging operation is completed, the bias current of the second switching transistor 16 is cut off, so that the second switching transistor 16 and the first switching transistor 15 are It is reversed and returned to a non-conductive state. After such an operation is performed, a playback operation is performed using a timer.Next, the recording operation, that is, the absentee recording operation will be explained. This operation is performed by operating the selection switch 12 to switch to the recording side terminal 12r and setting the timer device to a desired time. In this state, when the set time comes, power is supplied to the tape recorder through the timer device, and the first switching transistor 15 and the second switching transistor 16 become conductive through the above-described operation. When power is supplied to the operation circuit 4 and a reset operation is performed, the recording input terminal 5 provided in the operation circuit 4 is turned on by conduction of the selection switch 12 and the first switching transistor 15. And an L level signal is input to the reproduction input terminal 6. As a result, an H level switching signal is output to the playback output terminal 9 and the recording output terminal 8 provided in the operation circuit 4, and the playback switching circuit 10 and the recording switching circuit 11 become operational as described above. This constitutes the recording operation state of the tape recorder, and the light emitting diode 22 is driven to light up by the conduction of the display transistor 21.
Further, when the display transistor 21 becomes conductive, the charging transistor 2 is turned on as described above.
5 is reversed to a conductive state, and the capacitor 19 forming the time constant circuit 20 is quickly charged. As a result of this charging operation of the capacitor 19, the first switching transistor 15 and the second
Switching transistor 16 is immediately reversed back to a non-conductive state.

As described above, the playback and recording operations are performed by the timer device, but when the switching operation is performed and an H level switching signal is output to the playback output terminal 9, the capacitor 19 forming the time constant circuit 20
By quickly performing the charging operation, the first switching transistor 15 and the second switching transistor 16 are immediately inverted back to the non-conductive state, so that immediately after the playback or recording operation by the timer is started, Even if a stop operation is performed, the tape recorder can be stopped without any problem.

(g) Effects of the invention The control circuit of the invention includes a capacitor provided to control the input operation of the control signal to the operation circuit when a switching signal is output from the regeneration output terminal of the operation circuit when the timer is operating. Since the charging operation is performed quickly, even if a stop operation is performed immediately after the timer starts the playback or recording operation, the control signal for the playback or recording operation will not be input to the operating circuit again. Therefore, the switching operation to the stopped state etc. can be performed without any trouble. Therefore, since the time constant of the time constant circuit provided to control the input operation of the control signal to the operation circuit when power is supplied by the timer can be made sufficiently large, the time constant can be easily set. The present invention has the advantage of being able to. In addition, a display transistor is provided to display that the tape recorder is in a playback mode by lighting a light emitting diode when the charging transistor, which is provided to charge the capacitor, is in a conductive state. Since the charging transistor is controlled by the charging transistor, the circuit configuration is simpler compared to the case where a control element is separately provided to control the operation of the charging transistor, and the practical value of the present invention is extremely high. be.

[Brief explanation of the drawing]

The illustrated circuit is one embodiment of the control circuit of the present invention. Explanation of main figure numbers, 1... Recording switch, 2...
...Playback switch, 3...Stop switch, 4...
...Operating circuit, 10...Reproduction switching circuit, 11...Recording switching circuit, 12...Selection switch, 15...First switching transistor, 16...Second switching transistor, 19...Capacitor, 20 ... Time constant circuit, 21...display transistor, 25...charging transistor.

Claims (1)

[Scope of utility model registration request] A playback switch that is switched by a playback operation, a recording switch that is switched by a recording operation, and a playback switch that outputs a switching signal corresponding to each operation when a control signal is input by switching the playback switch and the recording switch. An operating circuit having an output terminal and a recording output terminal, a capacitor that is charged for a predetermined time when the power is turned on, and a selection switch that selects recording operation and playback operation using a timer;
a switching transistor that becomes conductive while the capacitor is being charged and inputs a playback control signal and a recording control signal to the operating circuit via the selection switch; A display transistor that becomes conductive when a switching signal is output and drives the light-emitting diode to light up; the operation is controlled by the display transistor; and when the display transistor is in a conductive state, it is biased and becomes conductive. When a switching signal is output to the playback output terminal of the operation circuit during recording and playback operations by a timer, the display transistor is inverted to a conductive state, and the charging transistor is turned on. A control circuit for a tape recorder, characterized in that the capacitor is quickly charged by the current supplied through the charging transistor when the capacitor is reversed to a conductive state.