DUAL-ACTION SINGLE-KEY MECHANISM

摘要

A switch assembly is provided to actuate a pair of switches using a single key cap, e.g. for a camera that utilizes a first switch to activate an image focusing function and a second switch to activate a camera shutter. The switch assembly comprises a first switch and a second switch, wherein the first switch partially or completely surrounds the perimeter of the second switch. The first switch comprises an upper conductive surface and a lower conductive surface that, when in contact, electrically couples two terminals for closing a circuit. The second switch comprises an actuator and a dome switch. When the key cap receives a first downward force, only the first switch becomes activated and a first electric circuit is completed. When the key cap receives a second downward force that is greater than the first force, the dome switch collapses and a second electric circuit is completed.