Screw fixing structure for heat dissipation unit and heat dissipation unit using same

Abstract

A heat dissipation unit includes a heat sink having a heat receiving zone and a screw fixing structure extended through each of four holes on the heat sink outside the heat receiving zone. The screw fixing structure includes a locating screw having a shank and a spring fitted around the shank; a hollow sleeve located outside the shank and the spring; and a spring stopper including two parallel elastic arms connected at one end and elastically disposed in the hollow sleeve to hold the spring in a compressed state. The spring stopper may be pushed downward to laterally push the two elastic arms open to move away from the spring, allowing the spring to release its elastic force upwardly. The four locating screws can synchronously and evenly apply their elastic force to the through holes outside the heat receiving zone, preventing the heat sink from damaging a contacted heat source.