JPS6139350Y2 - - Google Patents

Description

[Detailed explanation of the idea] This invention relates to an electronic metronome.

Since commonly used metronomes are mechanical, they are cumbersome to manufacture and are expensive even when mass produced, so they cannot be supplied at low cost.

The purpose of this invention is to provide an electronic metronome that can be provided at low cost.

In this invention, an electronic metronome is constructed from electronic components consisting of a low frequency signal source and an indicator. Electronic components are generally cheaper than machined components and can be supplied in large quantities. Therefore, according to this invention, a metronome having the same function as a mechanical metronome can be manufactured at low cost.

An embodiment of this invention will be described below in detail with reference to the drawings.

FIG. 1 shows an embodiment of this invention. In the figure, 1 is a low frequency signal source. In this example, it is assumed that the low frequency signal source 1 outputs a triangular wave. The triangular wave may be obtained by a triangular wave oscillator,
Alternatively, a rectangular wave output from a rectangular wave oscillator may be waveform-shaped into a triangular wave. In any case, the frequency of the low frequency signal required by the metronome is from 1 Hz or less to several Hz at the most.

A frequency changing means 2 is attached to the signal source 1 .
This frequency changing means 2 can be configured by, for example, a sliding resistor, and by adjusting the sliding resistor, it is possible to continuously vary the frequency from the very low frequency of 1 Hz or less to the frequency of several Hz from the signal source 1. , the frequency can be set to any desired frequency. In addition, step-like settings can also be made using a rotary switch. In any case, the arrangement is such that a desired tempo can be selected using a knob 3 shown in FIG. A triangular wave output from a signal source 1 is supplied to an indicator 5 through a clipper circuit 4. The clipper circuit 4 clips the positive and negative peak parts of the triangular wave output from the signal source 1 and
A flat portion S is formed as shown in the figure.

The indicator 5 uses a so-called double-oscillating indicator whose zero point is at the center of the scale. For example, in a double-oscillating type indicator, when the terminal 5b has the same potential as the terminal 5a, the pointer points to the zero point in the center, and when the potential of the terminal 5b is biased to the positive side, the pointer swings to the right, and the pointer points to the zero point at the center of the terminal 5b. When the potential is biased to the negative side, the pointer swings to the left.

Therefore, by supplying the indicator 5 with a triangular wave having flat portions S at the positive and negative peaks as shown in Fig. 3, the pointer of the indicator 5 moves at a constant speed between both ends of the scale, and The movement is stopped for a time corresponding to the length of the flat portion S at both end positions. If the time the pointer is stopped is approximately 10 to 20% of the time the pointer is moving, it can be seen as movement equivalent to that of a mechanical metronome. Therefore, the level at which the triangular wave is clipped in the clipper circuit 4 may be selected to be about 80 to 90% of the peak value of the triangular wave.

On the other hand, this invention provides a signal source 6 that generates a signal representing the tempo. This signal source 6
is configured to output a signal just before the triangular wave crosses the zero point and reaches the positive and negative plateaus S. For this purpose, for example, the comparator circuit 6a may be constructed by applying positive feedback to an operational amplifier, and a differentiating circuit 6b connected to the output side of the comparator circuit 6a. The comparator 6a has hysteresis characteristics due to positive feedback, and the fourth
A comparison output signal Pb as shown in FIG. B can be obtained. The timing of the rise and fall of this comparison output signal Pb can be set to a position immediately before reaching the flat part S of the triangular wave by appropriately setting the amount of positive feedback. This comparison output signal Pb is applied to the differentiating circuit 6
By differentiating with respect to b, a differential wave Pc as shown in FIG. 4C is obtained. This differential wave Pc is transferred to the amplifier 7
By supplying the signal to the speaker 8 through the tempo, the speaker 8 can generate a click sound indicating the tempo just before the pointer of the indicator 4 reaches the full scale position at both ends. This click sound can be turned off as desired by a switch 9. Note that a waveform shaping circuit 10 is provided before the amplifier 7.
By providing a waveform shaping circuit 10 and shaping the differential wave Pc into an appropriate waveform, it is possible to obtain a sound having an arbitrary timbre.

The circuit element explained in FIG. 1 can be housed in a case 11 as shown in FIG. 2, for example. An indicator 4 is attached to the upper surface of the case 11, and a tempo adjustment knob 3 is attached below the indicator 4.A scale is attached to the periphery of the tempo adjustment knob 3, and the lower limit of this scale is, for example, 40, and the upper limit is 40. A numerical value is written for the position, for example 208, and the intermediate scale is also marked with a numerical value between these. When you set the knob 3 to the desired tempo position, the speaker 8 will output the same number of times per minute as the set value.
In conjunction with this sound, the pointer of indicator 4 swings left and right. Therefore, it can be used in the same way as a regular metronome. In FIG. 2, 8 indicates a speaker, and 9 indicates a switch for turning on/off the sound.

As explained above, according to this invention, a metronome can be constructed entirely from electrical parts. Therefore, it can be manufactured at low cost. However, the pointer of the indicator 4 is moved by a triangular wave whose peak part is clipped to form a flat part, so the movement is the same as that of a mechanical metronome, and it can be used with the same feeling as a conventional metronome, making it easy to use. good. Furthermore, since the excitation signal that moves the pointer is a triangular wave, signal source 1
The circuit configuration can be simplified. Therefore, from this point of view, it can be manufactured at low cost.

In the above description, a case has been described in which a bidirectional type indicator with the zero point at the center is used as the indicator 5, but it is also possible to use an indicator with the zero point at the left end.
In this case, the amplitude of the triangular wave output from the signal source 1 may be selected so that the negative flat part indicates zero potential and the positive flat part indicates full scale.

Alternatively, instead of a triangular wave, the oscillator may output a pulse frequency modulated wave, a pulse width modulated wave, etc. that changes equivalent to the triangular wave, and the waveform shaping circuit may shape the waveform into a triangular wave.

[Brief explanation of drawings]

Fig. 1 is a connection diagram showing one embodiment of the electronic metronome according to this invention, Fig. 2 is a front view showing an example of the external appearance of the electronic metronome according to this invention, and Fig. 3
The figure is a waveform diagram for explaining the operation of the sound source of the electronic metronome according to this invention. 1...Low frequency signal source, 2...Frequency changing means,
4... Clipper circuit, 5... Indicator, 6... Signal source, 8... Speaker.

Claims (1)

[Scope of utility model registration request] a triangular wave signal source that outputs a low frequency triangular wave signal; a frequency changing means that changes the frequency of the output signal of the triangular wave signal source in correspondence with the tempo;
a circuit that forms flat portions at the positive and negative peak points of the triangular wave signal; and an indicator whose pointer is excited in positive and negative directions around the center of the scale by the triangular wave signal having the flat portions output from the circuit; An electronic metronome comprising: a signal source that generates a signal just before the flat portion of the triangular wave outputted from the triangular wave signal source; and a speaker that emits the signal from the signal source as sound.