Mechanical-acoustic earthquake alerter, has ball resting on minimum contact surface and made to falling by light earth impact and switch detecting contact at contact surface and releasing acoustic signal as soon as ball falls

摘要

The alerter has a monitor stand (4) and a ball (1) which rests on a minimum contact surface and is made to fall by a light earth impact. A switch (2) detects contact at the contact surface and releases an acoustic signal as soon as the ball falls, where the switch is a micro push button. A brake contact is provided as a control unit in the button.