How to create a switch that when pressed opens, but after a time delay returns to the original state?

Question

I am creating a buzzer driver that turns on when the output of an AND gate goes HIGH. What I would like to create is some way to shut off the signal to the buzzer by opening an SPST switch, but the switch must be able to return to the original closed state after a time delay so the AND gate can drive the buzzer again in the future.

I thought about creating an RC network to create the delay but I don't know how to implement a switch that after it is opened, closes again on its own after a certain amount of time. Ideas?

Answer 1

To add specifics to Dwayne's answer, a simple SPDT relay will do the trick.

^{simulate this circuit – Schematic created using CircuitLab}

Each time the alarm condition occurs, the buzzer sounds until the "Silence" button is pressed. Then the relay pulls in and stays that way until the alarm condition goes away.

Answer 2

The standard method of dealing with alarm noise-makers is to have a "Silence" push-button. Pressing the button causes a circuit to latch and disable the noise-maker.

The circuit automatically returns to normal when the condition causing the alarm is cleared. This allows the noise-maker to be operational again when the next alarm occurs.

It is rare that the silence duration is based on time rather than the source of the alarm signal being cleared but sometimes that is required. In those cases, the silence circuit is also (normally) reset to normal should the source of the alarm be cleared before the silence time period has elapsed.