JPS5842528B2 - Jikiki Rokusai Seisouchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic recording and reproducing device that electrically controls operations such as recording and reproducing.

2. Description of the Related Art Conventionally, magnetic recording and reproducing devices have been used in which when a command switch for recording, playback, etc. is momentarily turned on, an electric circuit is activated to perform an operation such as recording, playback, etc. according to the command from the command switch.

However, this type of device uses a pulse signal obtained by instantaneously turning on an operation command switch to set each command storage circuit composed of a flip-flop circuit or the like to perform a desired operation. For example, it has not been possible to connect a timer to the power cord and record a radio program or the like that you want to listen to while you are away.

The present invention solves these conventional drawbacks,
An example of this will be explained below with reference to the drawings.

In the figure, 1 is a reproduction command switch, 2 is a recording command switch, and 3 is a stop command switch, and the fixed contact a of one of the reproduction command switch 1 and the stop command switch 3 is grounded.

One fixed contact a of the recording command switch 2 is connected to the other fixed contact a of the reproduction command switch 2.

The other fixed contacts of the playback command switch 1 and the recording command switch 2 are connected to set terminals S of a playback command storage circuit 4 and a recording command storage circuit 5, respectively, which are configured by a flip-flop circuit formed by a combination of NAND gates. ing.

The other fixed contact of the stop command switch 3 is connected to the memory circuit 4 through the backflow prevention diodes 6 and 7, respectively.
, 5 are connected to the reset terminals R of the terminals.

Subsequently, the second output terminal Q of the reproduction command storage circuit 4 is connected to the reproduction drive circuit 9 via the inversion circuit 8, and the second output terminal Q of the recording command storage circuit 5 is connected to the recording drive circuit via the inversion circuit 10. 11.

This recording drive circuit 11 includes circuits for both left and right channels, and these circuits are connected to a recording mode switch 12.1.
The configuration is such that the recordable state can be switched by a group of switches (not shown) for bias current intermittent operation, etc., which are linked to each of the three.

That is, when the recording mode switches 12 and 13 are turned off as shown in the figure, the recording drive circuit 11 is configured to be in a recording enabled state.

The recording mode switches 12 and 13 are connected in series,
This series circuit is inserted and connected between the reset terminal R of the recording command storage circuit 5 and the ground.

Next, 14 is a power supply terminal, and a series circuit of a resistor 15 and a capacitor 16, a series circuit of a resistor 17 and a transistor 18, and a series circuit of a resistor 19 and a transistor 20 are connected between the power supply terminal 14 and the ground. ing.

A series circuit of a resistor 21 and a diode 22 is connected in parallel to the resistor 15, a diode 23 is connected between the connection point between the resistor 15 and the capacitor 16, and the base of the transistor 18, and the collector of the transistor 18 is connected to the base of the transistor 18. A capacitor 24 is connected between the base of the transistor 20 and the base of the transistor 20.
A resistor 25 is connected between the base of the transistor 20 and the power supply terminal 14.

The collector of the transistor 18 is connected to a fixed contact of the stop command switch 3 via an inverting circuit 26 and a diode 27 for preventing backflow.

The collector of the transistor 20 is connected to the set terminals of the reproduction command storage circuit 4 and the recording command storage circuit 5 through a series circuit of an inverting circuit 28 and a switch 29, and diodes 30 and 31 for preventing backflow connected to this series circuit. Connected to S.

Note that pull-up resistors 32 and 33 are provided between the power supply terminal 14 and the set terminal S and reset terminal R of the playback command storage circuit 4 and the recording command storage circuit 5, respectively, in order to normally maintain both terminals S and R at a high potential. and 34°35 are connected.

By the way, the above-mentioned reproduction command storage circuit 4 and recording command storage circuit 5
In each case, when the set terminal S is grounded and a low level signal (hereinafter referred to as a low signal) is supplied thereto, the first
, a high level signal (hereinafter referred to as H signal) and an L signal are output to the second output terminals Q and Q, respectively, and the reset terminal R is grounded, and when the L signal is supplied thereto, the first and second
It operates so that the outputs of the output terminals Q and Q are inverted to L and H signals, respectively.

The reproducing drive circuit 9 is operated by being supplied with an H signal from the inverting circuit 8, and runs the tape to perform reproduction.

The recording drive circuit 11 operates when an H signal is supplied from the inversion circuit 10, and switches the electric circuit so that recording can be performed.

Next, the operation of the above actual case will be explained.

First, when the playback command switch 1 is turned on momentarily, the playback command storage circuit 4 is set and an L signal is output to its second output terminal Q. This L signal is converted to an H signal via the inverting circuit 8 and played back. The drive circuit 9 is operated to run the tape and perform playback.

Next, when the playback command switch 1 and the recording command switch 2 are simultaneously pressed and turned on instantly, the playback drive circuit 9 is activated to start running the tape and the recording command storage circuit 5 is activated through the same process as described above. The second set
An L signal is output from the output terminal Q, and this L signal is converted to an H signal via the inverting circuit 10, and the recording drive circuit 11 is operated to switch the electric circuit to the recording state, thereby performing recording.

In this case, at least one of the recording mode switches 12, 13 must be open.

If both switches 12 and 13 are closed, the recording command storage circuit 5 is not set and recording cannot be performed.

Next, when the stop command switch 3 is momentarily turned on in the above-mentioned playback or recording state, the memory circuit in the set state is reset to the stop state.

Next, the operation of setting the device to recording or playback mode at a predetermined time using a timer will be explained.

First, a timer (not shown) is connected between the power terminal 14 and a power source (not shown), and set to turn on the power at a predetermined time.

Then, when a predetermined time set in the timer comes, power is turned on to the power terminal 14.

When the power is turned on, H is applied to the inverting circuit 26 via the resistor 17.
A signal is supplied, and this H signal is converted to an L signal via the inverting circuit 26, and then the diode 27 and the diode 6
．． 1 to the reset terminals of both the storage circuits 4 and 5 for a reproduction command and a recording command, thereby resetting both the storage circuits 4 and 5.

Further, when the power is turned on, the base potential of the transistor 20 becomes a high potential and the transistor 20 is turned on, and a current flows from the power supply terminal 14 to the ground side via the resistor 17, the capacitor 24, and the base/emitter of the transistor 20. The capacitor 24 is charged.

At the same time, the capacitor 16 is also charged via the resistor 15.

As charging of the capacitor 16 progresses and the potential across it reaches a potential sufficient to turn on the diode 23 and transistor 18, the diode 23 and transistor 18 turn on, and the collector of the transistor 18 becomes approximately equal to the ground potential.

Therefore, the inverting circuit 26 to which the H signal has been supplied until now
An L signal is applied to the input terminal of the inverting circuit 26, and the output of the inverting circuit 26 is inverted from the L signal to the H signal.

When the transistor 18 is turned on, one end of the capacitor 24, which is in a charged state, is grounded equilaterally, and the charge in the capacitor 24 is discharged.

Due to this discharge of the capacitor 24, a negative voltage is applied to the base of the transistor 20 for a certain period of time.
The transistor 20 is turned off.

The time period during which a negative voltage is applied to the base of transistor 20 is determined by the time constants of resistor 25 and capacitor 24.

When the transistor 20 is turned off, the H signal is supplied to the input terminal of the inverting circuit 28, which has been supplied with the L signal, and the output of the inverting circuit 28 is inverted from the H signal to the L signal.

At this time, selector switch 29 and recording mode switch 12.
The following three operations are performed depending on the on/off state of 13.

First, selector switch 29 is on, and recording mode switch 1 is turned on.
When at least one of 2.13 and 2.13 is open, the reproduction command storage circuit 4,
The recording command storage circuit 5 is set together, and both the playback and recording drive circuits 9 and 11 are operated, and the apparatus enters the recording state.

Next, the selector switch 29 is turned on and the recording mode switch 12 is turned on.
．． 13 are both closed, only the reproduction command storage circuit 4 is set by the L signal output from the inverting circuit, the reproduction drive circuit 9 is operated, and the apparatus enters the reproduction state.

Next, when the changeover switch 29 is turned off, neither the reproduction command nor the recording command memory circuits 4 and 5 are set, and the stopped state is maintained.

In this way, when the above-mentioned timer is activated and the power is turned on to the power terminal 14 according to the switching state of the selector switch 29 and the recording mode switch 12, 13,
The device is configured to be in one of a recording state, a playback state, and a stopped state.

In addition, the above-mentioned recording state and playback state are discriminated based on the switching state of the recording mode switch, and the number of contacts and circuits of the switch used is reduced.

As explained above, the magnetic recording/reproducing apparatus of the present invention uses a timer etc. in addition to setting or resetting an operation command storage circuit composed of a flip-flop circuit etc. by operating an operation command switch to perform a desired operation. The device is configured so that when the power is turned on, the device automatically enters either the recording or playback state depending on the state of the recording mode switch, and its configuration is extremely simple. It is a dog of practical effect.

[Brief explanation of the drawing]

The drawing is an electrical wiring diagram showing the device of the present invention when it is laid down. 1... Playback command switch, 2... Recording command switch, 3... Stop command switch, 4.
...Reproduction command storage circuit, 5...Recording command storage circuit, 8, 10°26.28...Inversion circuit, 9...Reproduction drive circuit, 11 ... Recording drive circuit, 12, 13... Recording mode switch, 29... Changeover switch.

Claims (1)

[Claims] 1. Connect a reset signal generation circuit that supplies a reset signal to the above two memory circuits when the power is turned on between the reset terminal of the tape constant speed running command memory circuit and the recording command memory circuit and the power supply terminal, and Between the reset terminal of the memory circuit and the power supply terminal, a set signal generation circuit that operates with a delay from the operation time of the reset generation circuit and supplies the set signal is connected via a changeover switch. A magnetic recording/reproducing device comprising a reset terminal connected to a reset signal source via a recording mode switch.