JPS5939758B2 - chime sound generator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a chime sound generating device that generates a chime sound with a lingering sound when a switch is turned on and off.

Generally, when a chime sound with a lingering sound is generated when a switch is turned on and off, a first time constant circuit operates when the switch is turned on, and a second time constant circuit operates when the switch is turned off. The circuits are provided separately, and each of these time constant circuits is configured to obtain a decay signal that produces a chime sound with a lingering sound.

However, in this type of device, the time constant circuit that operates when the switch is on and the time constant circuit that operates when the switch is off are configured separately, so variations in the electrical components that make up these time constant circuits may cause However, there was a problem in that it was almost impossible to completely match the characteristics of both time constant circuits, and the chime sound generated when the switch was turned on and the chime sound generated when the switch was turned off were always different. The present invention eliminates the above-mentioned conventional drawbacks, and aims to provide an excellent chime sound generating device that has a simple configuration and has the same attenuation characteristics whether the switch is on or off. That is.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The chime sound generating device of the present invention will be described below with reference to drawings of an embodiment.

In Fig. 1, 1 is a switch that is operated when generating a chime sound, etc., 2 is a constant current circuit that starts operating when transistor Ti is turned on, and 3 is a circuit that compares signals applied to terminals 3a and 3b. , a first comparator that outputs its output to the terminal 3c; 4 a second comparator that compares the signals applied to the terminals 4a and 4b with each other and outputs its output to the terminal 4c; 5 and 6, the first, constant current circuit for setting comparison voltages of second comparators 3 and 4, 7
is a power supply line for supplying DC power Vcc, 8 is an output terminal, 9 is an input terminal to which a modulation signal is applied, T1 to T8 are transistors, R1 to R9 are resistors, C
1 and C2 are capacitors.

FIG. 2 shows the signal waveforms of each part of the above embodiment, where a is the voltage waveform on the line 1a between the switch 1 and the resistor R1, b is the voltage waveform appearing at both ends of the capacitor C, and Va and Vb are respectively Terminal 3a of comparators 3 and 4
, 4b, c is the voltage waveform appearing at the collector of transistor T4, D,
e is an output waveform that appears at the output terminal 8 when no modulation signal is applied to the input terminal 9 and when it is applied to the input terminal 9. Next, the operation of this embodiment will be explained. Now, when switch 1 is pressed, a voltage of Vcc is applied to line 1a as shown in FIG. 2a, transistor T1 is turned ON, and constant current circuit 2 is operated.

Constant current circuit 2 charges capacitor C1 at a constant rate,
As shown in FIG. 2b, the voltage across the capacitor C1 is gradually increased. By the way, comparator 3 is connected to terminal 3b.
When the voltage applied to exceeds the first comparison voltage level Va,
Generates a constant output and turns on transistor T3. Further, the comparator 4 generates an output when the voltage applied to the terminal 4a exceeds the second comparison voltage level Vb, turning off the transistor T2. Since the terminals 3b and 4a of these two comparators 3 and 4 are commonly connected to the capacitor C, the capacitor C1 is connected to the transistor T3 during charging.
changes from off to on, and transistor T2 changes from on to off. That is, the transistor T3 connected in series
, T2 constitute an AND circuit, and the transistors T4 and T5 constituting the gate circuit can be turned on through the resistor R5 as shown in FIG. 2c. When transistors T4 and T5 are turned on, capacitor C2 is charged from power supply line 7 through transistor T5 and low resistance R6 for overcurrent protection in a very short time, and during charging and at the same time as charging is completed, resistor R7 for discharging time constant is charged. T6,
Through T7, the attenuated signal is outputted to the output terminal 8 as shown in FIG. 2d. Therefore, at this time, the transistor T
The base current of 6 is modulated and applied to the signal input terminal 9, and the transistor T8 is connected to 0N-0FF by the town signal.
By dividing the current through the output terminal 8, a signal having a frequency as shown in FIG. Next, when switch 1 is released, capacitor 1 gradually discharges, causing the voltage across it to drop as shown in FIG. 2b. Therefore, at this time, the comparators 3 and 4 operate in the same manner as described above, causing the transistors T4 and T5 to operate again as shown in FIG. By the way, in the above embodiment, since the transistors T4 and T5 constituting the gate circuit are composed of Pnp transistors and Npn transistors connected to the power supply side, the capacitor C2 can be charged with only a slight voltage drop.
The charging time of capacitor C2 can be significantly shortened.

As is clear from the above embodiments, the chime sound generating device of the present invention obtains a voltage that gradually rises when the switch is turned on using the first capacitor and gradually decreases when the switch is turned off. quickly charging the second capacitor when is between predetermined first and second levels;
It is configured to gradually discharge the charge accumulated in the second capacitor according to a predetermined time constant to obtain an attenuation signal when the level deviates from between the first and second levels, Therefore, it is possible to obtain the same attenuation characteristics when the switch is on and off, which is extremely advantageous in practice.

That is, according to the present invention, the attenuation characteristic itself is obtained only by the second capacitor and its discharge circuit, and even if there are variations in the various electrical components that make up these circuits, the attenuation characteristic itself is obtained at the time of switch-on. There is no difference between the attenuation characteristics during switch-off and the attenuation characteristics during switch-off, and there is an advantage that a chime sound generating device having the same attenuation characteristics can be obtained at all times. Furthermore, according to the present invention, the time constant circuit for obtaining the attenuation characteristic at switch-on and the time constant circuit for obtaining the attenuation characteristic at switch-off are both the same, which eliminates the need for conventional systems in which these are provided separately. As such, there is no need to separately design and adjust each time constant circuit, which is extremely advantageous in manufacturing, assembly, and other aspects.

[Brief explanation of the drawing]

FIG. 1 is a schematic electrical connection diagram of an embodiment of the chime sound generating device of the present invention, and FIG. 2 is an output waveform diagram of each part of the embodiment. 1...Switch, 3, 4...Comparator, Cl, C2...Capacitor, T1~T
7...Transistor.

Claims (1)

[Claims] 1. When the first capacitor is gradually charged when the switch is turned on and gradually discharged when the switch is turned off, and the voltage across this first capacitor is equal to or higher than a predetermined first level. a first comparator that generates a predetermined output, and a second comparator that generates a predetermined output when the voltage across the first capacitor reaches or exceeds a second level different from the predetermined first level. a comparator, a gate circuit which takes the outputs of the first and second comparators as input and generates a predetermined gate signal when the switch is turned on and off, respectively, and this gate circuit generates the gate signal. a second capacitor that is charged for a period of time and gradually discharged after the period;
Equipped with a transistor circuit that is turned on and off by the voltage across the second capacitor and a separately provided modulation signal, a chime sound with the same attenuation characteristics can be obtained both when the switch is on and when the switch is off. A chime sound generating device configured to