Large-angle hinge with automatic closing function

A large-angle hinge with an automatic closing function comprises a hinge cup and a fixed arm, the hinge cup is connected with the fixed arm through a four-bar mechanism, the four-bar mechanism comprises an inner arm, an outer arm, a front connecting rod and a rear connecting rod, the inner arm and the outer arm are hinged to the middle of the hinge cup, and the front connecting rod and the rear connecting rod are hinged to the hinge cup and the fixed arm respectively. The rear end of the outer arm is hinged to the fixed arm, the front end of the outer arm is hinged to the hinge cup, the rear end of the outer arm is hinged to the rear connecting rod, a cam sliding block is installed in the end of the front connecting rod, a connecting hole is formed in one side penetrating through the cam sliding block, correspondingly, a driving groove is formed in a port of the front connecting rod, and a driving shaft sequentially penetrates through the driving groove to be connected with the connecting hole. Synchronous sw