JPS6022398Y2 - volume control device - Google Patents

Description

[Detailed description of the invention] This invention relates to a volume control device suitable for application to, for example, a musical instrument, and in particular, in a device in which the volume is controlled by a foot pedal, the state of the volume changes suddenly every time the direction of movement of the foot pedal is reversed. However, it is an object of the present invention to provide a volume control device that can greatly change the volume with a small amount of movement.

For example, many musical instruments that utilize electrical loudspeaker systems are configured so that the volume can be adjusted using a foot pedal.

Volume adjustment using a foot pedal is normally configured so that the volume increases as the pedal is depressed.

Therefore, even if you try to rapidly change the volume by moving the foot pedal quickly, the volume will only change in the shape of a triangular wave as shown in FIG. 2A.

Therefore, for example, it is not possible to obtain a sound effect similar to a violin playing technique with fast picking using a guitar or the like.

The purpose of this invention is to provide a volume control device that can rapidly change the volume even with a small movement of the foot pedal, and thus can rapidly change the volume at a fast cycle.

In this invention, a switch is connected to both ends of the fixed terminal of the sliding resistor that is operated by a foot pedal, and the switch connects both fixed terminals of the sliding resistor to the input terminal (
or an output terminal) and a common potential point, and is provided with a means for detecting the direction in which the pedal moves, and each time the direction of pedal movement is reversed by this detection output, the holding circuit is inverted and the switch is activated. The amount of signal output to the output terminal can be changed suddenly by switching the output terminal.

An embodiment of this invention will be explained in detail below.

FIG. 1 shows an embodiment of this invention.

In the figure, 1 indicates a sliding resistor for volume adjustment operated by a foot pedal (not particularly shown), 2 indicates an input terminal,
3 indicates an output terminal.

That is, the signal supplied to the input terminal 2 is attenuated by an amount corresponding to the position of the slider 1c of the volume adjusting sliding resistor 1, and is output to the output terminal 3.

In this invention, switches 4 and 5 are connected to the fixed terminals 1a and lb of the sliding resistor 1 for volume adjustment, and the switches 4 and 5 connect both fixed terminals 1a and lb of the sliding resistor 1 to the input terminal 2 ( Alternatively, it is configured to be reversibly connected to the output terminal 3) and the common potential point 6.

In this example, a configuration is shown in which the input terminal 2 and the common potential point 6 are reversibly connected, and one fixed terminal 1a of the sliding resistor 1 is connected to the movable contact of the switch 5, and the other switch The other fixed terminal 1b of the sliding resistor 1 is connected to the movable contact 6.

The switches 4 and 5 can be, for example, relay contacts, and the movable contacts are mutually switched between a normally closed contact a and a normally open contact by de-energizing and energizing the relay coil RL.

Therefore, the normally closed contact a of the switch 4 and the normally open contact of the switch 5 are connected to the common potential point 6, and the normally open contact of the switch 4 and the normally closed contact a of the switch 5 are commonly connected and connected to the input terminal 2. do.

Further, the slider 1c of the sliding resistor 1 is connected to the output terminal 3.

On the other hand, 7 indicates means for detecting the direction in which the foot pedal moves.

In this example, a sliding resistor 8 that is operated in conjunction with the volume adjusting sliding resistor 1 is provided, and a differential circuit 11 consisting of a capacitor 9 and a resistor 10 is connected to the mover of the sliding resistor 8. The following shows the configuration.

For example, a positive voltage is applied to one fixed terminal of the sliding resistor 8, and the other fixed terminal is connected to a common potential point.

With this configuration, when the foot pedal is depressed, a positive differential pulse Pa is outputted to the output terminal 12 as shown in FIG. 3, and when the pedal is returned from the depressed state, a negative differential pulse Pb is output. is output.

These differential pulses Pa and Pb are applied to the holding circuit 13 to invert the state of the holding circuit 13.

For example, the holding circuit 13 is configured to form a flip-flop by feeding back the output of an operational amplifier to a non-inverting input terminal and applying positive feedback.

The differential pulse outputted to the output terminal 12 is applied to the non-inverting input terminal of the operational amplifier, and the relay coil RL is energized and controlled by the output of the holding circuit 13.

In the above configuration, in the initial state, that is, when the foot pedal is not depressed, the slider 1c of the sliding resistor 1 is biased toward the switch 5 side, and the slider of the sliding resistor 8 is biased toward the common potential point side. It is assumed that it is biased.

When the power is turned on in this state, a charging current flows from the positive power supply to the capacitor 9 because a certain amount of residual resistance always exists between the slider of the sliding resistor 8 and the common potential point 6. , a differential pulse Pa of positive polarity is generated at the output terminal 12.

Therefore, by supplying this differential pulse Pa, the output of the holding circuit 13 becomes positive, and the relay coil RL is energized.

Therefore, the switches 4 and 5 are in contact with the normally open contact side, the input terminal 2 is connected to the fixed terminal 1a of the sliding resistor 1, and the fixed terminal 1b is connected to the common potential point 6.

Therefore, the volume is adjusted to give the maximum amount of attenuation.

From this state, when the foot pedal is depressed gradually, the volume increases gradually as shown in FIG.

For example, when the volume reaches a level of 0 as shown in Figure 4,
When this point is reached, if the foot pedal is returned a little, the charging voltage of the capacitor 9 is discharged through the resistor 10, so that a negative differential pulse pb is outputted to the output terminal 12.

Therefore, the state of the holding circuit 13 is reversed, and its output becomes a negative polarity state.

Therefore, the relay coil RL is deenergized and the switches 4 and 5 are switched to the normally closed contact a side.

Therefore, the sound volume shifts to point f shown in FIG. 4 and rapidly attenuates.

When the foot pedal is gradually returned to its original position after moving to point f, the volume gradually increases because the input terminal 2 is connected to the fixed terminal 1b side of the sliding resistor 1 at this time.

When the foot pedal is pressed back to zero, the volume will be maximized.

When the foot pedal is slightly depressed at point d, where the volume is at its maximum, a positive differential pulse Pa is output to the output terminal 12 of the minute detection circuit 7, and the state of the holding circuit 13 is reversed.

Therefore, the relay coil RL is energized and the switches 4 and 5 are switched to the normally open contact side.

Therefore, the volume suddenly changes from the highest state to the lowest state.

As described above, according to this invention, the volume can be easily and suddenly changed by operating the foot pedal.

For example, as shown in Figure 2B, it is possible to gradually increase the volume and suddenly change it to zero, or to gradually decrease the volume and suddenly change it to the maximum. This has the effect of making it possible to play the violin by picking.

In the above, the slider 1C of the volume adjustment sliding resistor 1 is connected to the output terminal 3, but for example, as shown in FIG. 5, the slider 1c is connected to the input terminal 2, and both fixed terminals 1a, lb can also be connected to the output terminal 3 through the switches 4 and 5, and it will be readily understood that the selection can be made arbitrarily.

In addition, although the case has been described in which the means 7 for detecting the direction of movement of the foot pedal is configured by the sliding resistor 8 and the differential circuit 11, another method is to attach a magnet to the foot pedal, and place the big abutment in opposition to the magnet. It is also possible to attach a coil and perform inversion control of the holding circuit 13 by the electromotive force induced in the pickup coil.

[Brief explanation of drawings]

Fig. 1 is a connection diagram showing an embodiment of this invention, Fig. 2 is a waveform diagram showing a comparison of changes in volume between a conventional volume control device and a volume control device according to this invention, and Fig. 3 is a FIG. 4 is a waveform diagram for explaining the operation of this invention, FIG. 4 is a graph for explaining the operation of this invention, and FIG. 5 is a connection diagram showing another embodiment of the main part of this invention. 1... Sliding resistor for volume adjustment, 2...
Input terminal, 3... Output terminal, 4, 5...
- Switch, 7... Means for detecting the direction of movement of the foot pedal, 13... Holding circuit.

Claims (1)

[Scope of utility model registration request] A switch is connected to both fixed terminals of the sliding resistor that is operated in conjunction with the foot pedal, and these switches connect one fixed terminal and the other fixed terminal of the sliding resistor to the input terminal (or output terminal) and a common potential. The foot pedal is configured such that it can be reversibly connected to a point, and is also provided with means for detecting the direction in which the foot pedal moves, and the holding circuit is controlled by the detection output of the detecting means, and the switch is switched depending on the state of the holding circuit. Configured volume control device.