| 摘要 |
<p>The invention pertains to an electronic alarm particularly designed to indicate reverse movement of vehicles. The alarm utilizes a synthetic plastic housing having a cavity defined therein which intersects the housing at an exterior surface. A sound producing diaphragm, the motor for vibrating the diaphragm, and the electronic control circuit, are all mounted upon a diaphragm mounting assembly which is received within the housing cavity forming a cavity cover. The diaphragm is located in opposed relationship to a cavity sound reflective base, and an air passage surrounding the diaphragm mounting assembly transmits sound vibrations through the cavity, and through ports defined in the diaphragm assembly at the cavity opening.</p> |
