Abstract: A hinge assembly (9) includes a shell (1), a coil spring (2), a shaft (3), and two bolts (4). The shell defines a cavity (12) therein, with one end of the shell being closed and the other end being open. Two holes (14) are defined in the shell near the open end. The shaft includes a cam (32), a soleplate (38), and an interconnecting neck (34). The cam includes a cam surface (324) at one end thereof, the cam surface including peaks and valleys. The spring and the shaft are received in the shell, but with the soleplate exposed outside. The spring biases the cam surface against the bolts no matter what part of the cam surface abuts the bolts. Because the hinge assembly of the present invention is effectively an integrated, modular structure, it is easily incorporated into a portable foldable device such as a mobile phone.

Abstract: A hinge assembly for joining a cover to a main body of a foldable device includes a hollow housing (10), a spring (20), a shaft (30), and a positioning pin (40). The housing includes an open end, an opposite rear end (11). The spring is received in the housing. The shaft includes a cam portion (34) received in the housing, and a shaft portion (32) passing through the spring and extending out through the rear end. One end of the spring biases the cam portion, and an opposite end of the spring biases the rear end. The pin is transversely retained in the housing near the open end, and is rotatable relative to the shaft and movably engaged with a cam surface of the cam portion. When the rear end is urged in an axial direction by the spring, the cam surface causes the pin to rotate the housing.

Abstract: A hinge assembly (9) includes a shell (1), a coil spring (2), a shaft (3), and two bolts (4). The shell defines a cavity (12) therein, with one end of the shell being closed and the other end being open. Two holes (14) are defined in the shell near the open end. The shaft includes a cam (32), a soleplate (38), and an interconnecting neck (34). The cam includes a cam surface (324) at one end thereof, the cam surface including peaks and valleys. The spring and the shaft are received in the shell, but with the soleplate exposed outside. The spring biases the cam surface against the bolts no matter what part of the cam surface abuts the bolts. Because the hinge assembly of the present invention is effectively an integrated, modular structure, it is easily incorporated into a portable foldable device such as a mobile phone.