Abstract: An exemplary hinge assembly includes a hollow housing (100), a shaft (300), an urging mechanism (400), a cam (500), and a follower (700). The housing includes an open end, and a hole (104) in an opposite second end. A peripheral wall of the housing at the open end defines two pinholes (112). The shaft 300 includes a fixing portion and a stopper portion (204). The urging mechanism is received in the housing and located around the shaft. The cam defines a cam hole (506) therethrough, and includes a cam portion (502) received in the housing. One end of the cam portion has a cam surface (508). The cam hole engagingly receives the shaft, so that the cam rotates with the shaft. The urging mechanism biases the cam. The follower is fixed in the pinholes. The follower rotates relative to the shaft, and is movably engaged with the cam surface.