JPS6112000Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to an automatic adjustment device for automatically adjusting electronic equipment such as tape recorders, radio receivers, amplifiers, etc. to a state where the best characteristics can be obtained. To provide a device capable of performing work quickly and reliably at a low price.

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows the adjustment mechanism portion of the device of this embodiment. In the figure, reference numeral 1 indicates a circuit board of a tape recorder, and reference numeral 2 indicates an oscillation coil for a recording bias oscillator mounted on the board 1. By rotating the movable core 2a within the coil 2 and moving it up and down, the recording bias current is changed. Various parts are mounted on the board 1 and are in a completed, operable state, but are shown in a simplified manner in the figure.

Reference numeral 3 denotes an adjustment mechanism which can be raised and lowered to rotate the movable core 2a. A driver bit 5 is rotatably supported on the lower plate 4 of the adjustment mechanism 3, and a pulse motor 7 is fixed to the upper plate 6. The rotating shaft 7a of this motor 7 and the driver bit 5 are connected by a universal joint 8, and when the rotating shaft 7a of the motor 7 rotates once, the driver bit 5 also rotates once.
It is configured to rotate.

FIG. 2 shows the circuit configuration of this device for controlling the rotation of the pulse motor 7. As shown in FIG. The pulse motor 7 has its rotational direction controlled and rotationally driven by a pulse motor driver 9.
is activated by output pulses from a pulse motor control circuit that provides clock pulses. The rotation of the pulse motor 7 rotates the movable core 2a shown in FIG. 1, and in connection with this, the output of the electronic device, in the case of this embodiment, the recording bias current of the tape recorder changes. The changing output of the electronic device is amplified by the measurement amplifier 11, and then converted into a digital signal by the analog-to-digital converter 12, and this conversion output is stored in a storage circuit (in this embodiment, a random access memory, so-called RAM). 1
3 is written. In this case, as a control signal for starting and ending the conversion operation of the analog-to-digital converter 12, and as a write control signal for the storage circuit 13,
A clock pulse output from the pulse motor control circuit 10 is used. This is the third
To further explain using the figure, the clock pulse a shown in figure A is applied to the pulse conversion circuit 14, where it converts the analog-to-digital conversion operation start signal b with the minimum pulse width of 200 ns shown in figure A and the maximum pulse width shown in figure C. A conversion operation end signal c with a pulse width of 25 μs is generated, and a write signal d with a minimum pulse width of 1 μs shown in FIG. And signals b and c are analog. - The signal d is supplied to the digital conversion circuit 12 and the storage circuit 13. The data stored in the memory circuit 13 is processed by a microcomputer (central processing unit, so-called
A comparator circuit (not shown) in the computer 15 compares the optimum recording bias current value which is read into the computer 15 according to a command from the CPU 15 and is preset in the computer 15 and the read memory value. As a result of this comparison, if the two values match, the adjustment work is completed, but if they do not match, a mismatch signal e is output, which controls the pulse motor control circuit 10, and this circuit 10 One or more clock pulses are newly output in succession.

Next, the operation of the above embodiment will be described.
When the electronic device is brought under the adjustment mechanism 3, the adjustment work starts automatically. First, the adjustment mechanism 3 is lowered and the tip of the driver bit 5 is inserted into the groove of the movable core 2a. Then, the pulse motor control circuit 10 outputs a clock pulse a, which rotates the pulse motor 7 and moves the movable core 2a.
is rotated by a predetermined angle (0.9 degrees per clock pulse in this embodiment). At the same time as the start of this rotation, i.e., in synchronization with the falling edge of the clock pulse a shown in FIG. 3, a conversion operation start signal b is output, and the analog-digital converter 12 performs a preliminary conversion operation for converting the recording bias current from the electronic device into a digital signal for the pulse width time of the signal b, 200 ns. After this preliminary conversion operation, the conversion operation proceeds to a proper conversion operation, and ends with the rising edge of the conversion operation end signal c. This signal c is also synchronized with the falling edge of the clock pulse a, and this pulse width time of 25 μs is the time required for the conversion operation. After the conversion operation is completed, the conversion output is immediately written into the memory circuit 13 under the control of a write signal d synchronized with the falling edge of the conversion operation end signal c. The write time is the pulse width time of 1 μs of the signal d. In this way, the writing operation to the memory circuit 13 can be completed in one go before the rotation of the motor 7 is completed, and after this writing is completed, the operation immediately proceeds to a comparison operation in the computer 15. That is, the stored output is compared with a preset optimum adjustment value in the computer 15, and if the two values do not match, a command signal e is supplied to the pulse motor control circuit 10 to output a new clock pulse a', and the above-mentioned operation is repeated. This operation is continued until the comparison results in a match.

In addition, if the output from the electronic device is significantly different from the set value after starting the adjustment work,
The motor 7 is continuously rotated by outputting a plurality of clock pulses a, and the output value of each pulse is continuously stored in the memory circuit 13, and then the computer 15 compares them all at once. The rotation angle of the motor may be automatically adjusted to the position corresponding to the stored value closest to the set value.

Furthermore, in the above embodiment, the output of the electronic device is measured while the motor 7 is rotating, but this is because the characteristics of the recording bias current to be adjusted can be predicted in advance. Since the rotation angle can be considered to change linearly within 0.9 degrees, there is no problem even if the measurement is performed while the motor is rotating. However, if extremely accurate adjustment is required, it goes without saying that it is better to perform a series of operations such as analog-to-digital conversion, storage, and comparison after the rotation of the motor 7 has stopped.

Furthermore, although this example describes the case where the recording bias current is adjusted by adjusting the core of the oscillation coil, it can also be applied as is to various other adjustments, such as adjusting the gain of an amplifier by adjusting a semi-fixed resistor. be able to. It goes without saying that the pulse motor 7 also includes a stepping motor.

As explained above, the automatic adjustment device for electronic equipment of the present invention digitally converts the output of the electronic equipment and stores it, compares the stored output with a preset optimal adjustment value, and generates a pulse based on the comparison result. Since the rotation angle of the motor is controlled and adjusted, highly reliable adjustment work can be done practically and quickly.In addition, the clock pulses for controlling the pulse motor can be transferred to an analog/digital converter and memory. Since it is also used as a circuit operation control signal, the configuration can be simplified and the reliability of operation can be increased, making it possible to provide a device with excellent performance at a low price.

[Brief explanation of the drawing]

Fig. 1 is a side view showing the adjustment mechanism portion of an automatic adjustment device according to an embodiment of the present invention, Fig. 2 is a block diagram showing the circuit configuration of the same device, and Fig. 3 A to E explain the operation of the same device. FIG. 1... Circuit board, 2... Oscillation coil, 2a...
Movable core, 3... Adjustment mechanism, 5... Driver bit, 7... Pulse motor, 9... Pulse motor driver, 10... Pulse motor control circuit, 12... Analog-digital converter, 1
3... Memory circuit, 14... Pulse conversion circuit, 15
...Computer, a...Clock pulse, b...
...conversion operation start signal, c...conversion operation end signal,
d...Write signal.

Claims (1)

[Scope of utility model registration request] A driver bit that is engaged with the rotating part of an electronic component to be adjusted in an electronic device, a pulse motor that rotationally drives this bit, and a digital signal that converts the output of the electronic device that changes in relation to the adjustment of the electronic component to be adjusted. The analog-to-digital converter to be converted, the storage circuit that stores the output of this converter, and the output of this storage circuit are compared with a preset optimum adjustment value, and the rotation of the motor is controlled according to the comparison result. An automatic adjustment device for electronic equipment, comprising a control circuit for controlling the pulse motor, and configured to use a clock pulse for controlling the pulse motor as an operation control signal for an analog-to-digital converter and a memory circuit.