Safety mechanism for a watertight watch having a piezo electric buzzer

摘要

A watch of the watertight type has a housing including a downwardly apertured housing portion for transmitting sound. A diaphragm is attached to the housing in a manner effecting a watertight seal. The diaphragm is capable of flexure toward and away from the apertured housing portion. A piezo electric buzzer element is secured internally of the diaphragm and is responsive to electrical excitation for producing a buzzing sound. An electrical circuit is connected to the piezo element for electrically exciting the piezo element. A safety mechanism is provided for preventing an excessive amount of flexure of the diaphragm in response to pressure acting thereon. A first safety element is secured to the diaphragm. A second safety element is secured to the housing. The first safety element is movable, with the diaphragm, relative to the second safety element in an inward direction away from the apertured housing portion. The second safety element includes a stop for contacting the first safety element to limit the amount of flexure of the diaphragm.