Abstract: A rotor assembly includes a rotation axis, a propeller, an active ring, a driver link, and a reciprocating spring. The propeller includes a hub portion and fan blades. The hub portion is located on one end of the rotation axis, and the inner sidewall of the hub portion has a gear structure surrounding the rotation axis. The active ring sleeves on the rotation axis. The driver link is pivotally connected to the active ring. The reciprocating spring is telescopically disposed on the active ring and abuts against the driver link. When the rotation axis drives the active ring to rotate, the driver link abuts against the gear structure of the hub portion and compresses the reciprocating spring. When the rotation axis stops rotating, the reciprocating spring returns to an initial position to push the driver link to separate from the gear structure.

Abstract: A cold plate module includes a cold plate, a structural piece, a frame and an absorbing element. The cold plate includes a body, an inlet and an outlet. The body has a first and a second surfaces. The first surface abuts a heat source on a motherboard. The inlet and the outlet communicate with the body. The structural piece has a third and a fourth surfaces. The third surface connects the second surface. The structural piece connects the motherboard. The frame connects and defines a space with the fourth surface. The inlet and the outlet locate within the space. The absorbing element connects the fourth surface within the space. The inlet and the outlet penetrate through the structural piece and the absorbing element. The absorbing element locates between the fourth surface and both of an entrance of the inlet and an exit of the outlet.