JPS6255323B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a volume adjustment device suitable for use in various electronic devices such as stereo equipment and television receivers.

Conventionally, in various electronic devices of this type, a volume control volume and a power switch are provided separately. Further, the volume adjustment and the power on/off may be performed not only manually, but also by remote control using a remote controller. By the way, when the power switch is turned off, the volume adjustment volume remains fixed at the setting position when the power was turned off, so when the power switch is turned on again, the sound corresponding to this setting position suddenly changes to the speaker. Therefore, in some cases, an extremely large output may be obtained and it is inevitable that this will adversely affect the circuit system, speakers, etc. In particular, the remote controller is only equipped with buttons for turning on and off the power, and controlling volume increases and decreases, and there is no scale for the volume setting position that can be used as a guide to the volume (actually, there is no scale). cannot be turned on), when turning on the power using this remote controller,
It's hard to tell how loud it is. Also, when the power to an electronic device is shut off, the power to the motor that controls the volume adjustment volume inside the device according to instructions from the remote controller is also cut off, so the volume adjustment volume's setting position when the power is turned off is the same as the setting position when the power is turned on. Therefore, there is a risk that a loud impact sound will be output from the speaker when the power is turned on.

In view of this, the present invention uses a simple circuit configuration so that the sound is output from the speaker only after the volume adjustment volume is rotated or slid to a preset position when the power is turned on. It is an object of the present invention to propose a volume adjustment device that prevents loud sounds from being suddenly output from a speaker and having an adverse effect on a circuit system, speakers, etc.

Hereinafter, an example of the apparatus according to the present invention will be explained with reference to the drawings. 1 is a low frequency signal source, 2 is a volume control volume, and 3 is an amplifier for low frequency signals. The output is supplied directly to the speaker 4. 5a and 5b are DC power supplies whose connection points are grounded. A circuit passing through the collector-emitter-resistor 7a-7b-emitter-collector of the PNP transistor 6b is connected to the series circuit of the power supplies 5a and 5b, and the connection point of the resistors 7a and 7b is connected to the motor 8. This motor 8 drives the above-mentioned sound volume adjustment volume 2.
A series circuit consisting of normally open switches 9a and 9b is connected to the series circuit of the power supplies 5a and 5b described above, and the connection point of these switches 9a and 9b is normally connected to the bases of the transistors 6a and 6b described above. It is something that This switch 9a, 9b
may be operated manually or by remote control. Therefore, if the connection point between the switches 9a and 9b is connected to the bases of the transistors 6a and 6b, turning on the switch 9a turns on the NPN transistor 6a, which connects its collector, emitter, resistor 7a, and motor 8. A current is supplied from the power supply 5a in the direction of the arrow a through the power supply 5a, and the volume 2 is thereby rotated, for example, counterclockwise, thereby reducing the volume. Also, by turning on switch 9b
PNP transistor 6b turns on and its collector
Power supply 5 through emitter resistor 7b-motor 8
Assume that a current is supplied from b in the direction of arrow b, thereby rotating the volume 2 in the opposite direction to that described above to increase the volume.

In the present invention, a preset resistor 10 and a main volume (volume 2 for volume adjustment in this example) are used.
a detection volume 11 that detects the operation position of the main volume 2 that is linked with the main volume 2; and a control means 40 that moves the slider of the operation position detection volume 11 to a position set by a preset resistor.
It has

That is, in the control means 40, the reference potential obtained in the above-mentioned preset resistor 10 is
The detection potential V ₂ (both V ₁ and V ₂ include negative potentials in this example) obtained in the detection volume 11 with respect to V ₁ and the potential V ₃ and its height (with respect to V ₁₎
When V ₂ is at a high potential, it is + _, and when it is at a _low potential, it is _- . a discrimination circuit 12 for discriminating, a switching control circuit 19, and a switching device 2 that is switched by this
0 is provided, and when there is an output from the discrimination circuit 12 when the power is turned on to the electronic device, that is, when the potential ±V ₃ is outside the range of the set potential -V ₀ to +V ₀ , the output from the discrimination circuit 12 is set as 0. The detection volume 11 is operated by the output so that the potential ±V ₃ falls within the set potential range.

In order to obtain the above-mentioned potentials _V1 and _V2 , in this example, the volumes 10 and 11 are connected to the power supplies 5a and 5.
They are connected to the series circuit of b, respectively, and the discrimination circuit 1
2, window comparators 15a and 15b are configured by pairing the output terminals of the differential voltage detector (amplifier) 13 to which the above-mentioned potentials V ₁ and V ₂ are applied via resistors 14a and 14b, respectively. are connected to one input terminal of each of the power supplies 5a and 5.
Resistors 16a-17a-1 for the series circuit of b
Connect the series circuit of 7b-16b and connect the resistor 17a.
and 17b are grounded, and resistors 16a and 1
The connection point with 7a and the connection point with 16b and 17b are respectively connected to the other input terminal of window comparators 15a and 15b, and the respective output terminals of both comparators 15a and 15b are connected to each other through resistors 18a and 18b. The figure shows a case in which it is configured by connecting to. and resistor 1
The voltages (the above-mentioned set potentials) +V ₀ and -V ₀ applied to the other input terminals of the window comparators 15a and 15b are determined by the resistance values of 7a and 17b.

Also, the switching control circuit 19 is an NPN transistor 21
and the emitter of the NPN transistor 22 are connected together, the collectors of both transistors are connected together and connected to the positive side of the power supply 5a through the resistor 25, and the emitters of each of the PNP transistors 23 and 24 are connected to the emitter of the power supply 5a. The base of the transistor 23 is connected to the collectors of the transistors 21 and 22, and the collector is connected to the transistor 24.
The collector of the transistor 24 is connected to the base of the switch device 20 and is grounded through the resistor 26, the collector of the transistor 24 is grounded through the coil 27 of the relay serving as the switch device 20, and the emitter of the transistor 21 and the base of the transistor 22 are respectively grounded. There is.

In this case, the switch device, ie, the relay 20, has three relay contacts 28, 29, and 30, and the movable contact 28a of the contact 28 is connected to the transistor 6.
a and 6b, fixed contact 28b is connected to the connection point of switches 9a and 9b, fixed contact 28c is connected to the connection point of resistors 18a and 18b as output terminals of the discrimination circuit 12, and the movable relay contact 29 Contact 29a is the resistor 18a and 18 mentioned above.
The fixed contacts 29c are connected to the bases of the transistors 21 (and therefore the emitters of the transistors 22) of the switching control circuit 19 to the connection points b, and the movable contacts 30a of the relay contacts 30 are connected to the output terminals of the amplifier 3. , the fixed contact 30b is connected to one end of the speaker 4. It is assumed that these relay contacts 28, 29, and 30 are in the state shown by solid lines when the relay 20 is in a non-energized state (no current flows through the relay coil 27).

To explain the operation of the above-mentioned configuration, before the power is turned on (the power is supplied to the amplifier 3 and the discrimination circuit 12 and the switching control circuit 19), each relay contact 28, 29, and 30 is in the state shown by the solid line. be. When the power is turned on in this state, potentials V ₁ and V ₂ are obtained from the volumes 10 and 11, and these are compared by the comparator 13. Now temporarily V ₁ <
Assume that V ₂ and +V ₃ is obtained from the comparator 13, and that V ₃ >V ₀ .

At that time, the positive potential +V ₃ obtained from the output terminal of the window comparator 15a is applied to the bases of the transistors 6a and 6b through the contacts 28c-28a of the relay contact 28. Therefore, in this case, the transistor 6a is turned on, and a current is supplied from the power supply 5a to the motor 8 in the direction of the arrow a through the transistor 6a, which drives the motor 8. As a result, the main volume 2 and the detection volume 11 move counterclockwise, for example. operated, i.e. the potential V ₂ becomes V ₁
manipulated to approach. In this case, the transistor 6a receives a switching-controlled voltage (current) from the comparator 15a.

In this state, the voltage obtained at the connection point of the resistors 18a and 18b is applied to the base of the transistor 21 and the emitter of the transistor 22 of the switching control circuit 19.
is turned on, thereby turning on transistor 23, which turns off transistor 24, that is, relay 20 is in a non-energized state, so that each relay contact 28, 29, and 30 continues to be in the state shown by the solid line, respectively. However, the above-described operation continues.

In this way, when the potential V ₂ approaches the reference potential V ₁ and the potential +V ₃ falls within the range of the set potential -V ₀ to +V ₀ , no output can be obtained from the window comparator 15a, and as a result, the transistors 21 and 23 The respective transistors are turned off, and the transistor 24 is turned on. Therefore, the relay 20 is energized, the relay contacts 28, 29 and 30 are respectively switched to the state shown by the dotted lines, and the output from the amplifier 3 is supplied to the speaker 4. Therefore, by operating the switch 9a or 9b, the motor 8 can be rotated in any direction, that is, the volume can be adjusted freely. During this adjustment, even if the potential V ₂ again becomes significantly different from the reference potential V ₁ , the relay contact 29 is switched to the state shown by the dotted line.
The switching control circuit 19 is not controlled by the output from the discrimination circuit 12.

The above is about the case where V ₂ is higher than the potential V ₁ , but if V ₁ > V ₂ , the output from the window comparator 15b causes the transistor 6b to
is turned on, and current is supplied to the motor 8 in the direction of arrow b from the power supply 5b, which rotates the main volume 2 and the detection volume 11 clockwise, causing the potential _V2 to approach the reference potential _V1 . be done.
In this case, in the switching control circuit 19, transistors 22 and 23 are turned on, and transistor 24 is turned off.

In this way, the potential -V ₃ changes from the set potential -V ₀ to +
When it falls within the range of V ₀ , relay 20
is energized, the relay contacts 28, 29 and 30 are switched to the state shown by the dotted lines, and thereafter the volume can be adjusted arbitrarily by operating the switches 9a and 9b, as described above.

Furthermore, when the power is turned on, the potential _V2 is already close to the reference potential _V1 , that is, the potential ± _V3 is the set potential _-V0 to +
When it is within the range of V ₀ , neither of the transistors 21 and 22 of the switching control circuit 19 is turned on, so the transistor 23 is also not turned on, and therefore the transistor 24 is immediately turned on and energizes the relay 20. Since each relay contact 28, 29 and 30 is switched to the state shown by the dotted line, the switches 9a and 9b are immediately used to operate the motor 8, that is, to control the main volume 2.
operations can be performed.

As described above, the main volume 2 can be operated by operating the switch 9a or 9b, but the next time the power to the electronic device is cut off, the relay 20 will be in the de-energized state, and will therefore switch to the state shown by the solid line. In other words, it can handle power-on again.

The main volume 2, the detection volume 11 for detecting its operating position, and the presetting resistor 10 are arranged as a resistance device on one axis as shown in FIG. 2, and the presetting resistor 10 is connected to the operating knob. 31, the preset value is set, and the main volume 2 and detection volume 11 are manually operated knob 3.
2 and is also adjusted by the motor 8 via a transmission means (gear).

According to the present invention described above, when power is turned on to the electronic device, the main volume 2 is automatically operated to the state set in advance by the preset volume 10, and then the switching control circuit 19 is operated to cause the speaker 4 to emit the sound. Since the preset volume 10 is set appropriately, a sound louder than the speaker 4 will be suddenly emitted when the power is turned on, which may disturb the surroundings or have a negative impact on the circuit system, speakers, etc. It is possible to prevent this from happening.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of the volume adjusting device of the present invention, and FIG. 2 is a front view of the resistance device. 2 is the main volume, 10 is the preset resistor,
11 is a detection volume, and 40 is a control circuit.

Claims (1)

[Claims] 1 A voltage corresponding to the difference in position between the main volume, the operation position detection volume linked with the main volume, the preset volume, and the slider of the operation position detection volume and the slider of the preset volume. A discriminating circuit determines whether the voltage is within a predetermined range, and a slider of the operation position detection volume is moved to a position of the preset volume so that the voltage falls within a predetermined range according to the output of the discriminating circuit. A control means for moving the slider to a position; and a control means for detecting that the voltage falls within a predetermined range by the output of the discriminating circuit when the power switch is turned on, and connecting a load to the output of the amplifier; A volume adjustment device characterized by being provided with a switching control circuit that energizes the device so that it can be operated manually.