Patent ID: 6983514

Claim:
A pivot hinge comprising a base plate ( 10 ), a shaft ( 20 ), a spring ( 40 ), a ring ( 50 ) and a locking piece ( 60 ), wherein the base plate ( 10 ) has a first end defined with plural locating holes ( 11 ) for securing the pivot hinge onto an electronic device, and has a pivot tube ( 12 ) formed on a second end of the base plate ( 10 ), wherein the pivot tube ( 12 ) defines a gap ( 121 ) having an edge from which a first plain facet ( 13 ) extends, and a tooth ( 131 ) erects from a first end of the first plain facet ( 13 ); the locking piece ( 60 ) has an oval hole ( 61 ) defined in its center, and a notch ( 62 ) defined on a perimeter of the locking piece ( 60 ) to correspond to the tooth ( 131 ) when the notch ( 62 ) and the tooth ( 131 ) are engaged; the shaft ( 20 ) has a head end, a bottom end and a middle section connected between the head end and the bottom end, wherein the middle section having an external surface on which a second plain facet ( 23 ) is formed, and an angular section ( 22 ) with a locating block ( 221 ) is formed on the head end of the shaft ( 20 ) to be inserted through the oval hole ( 61 ) of the locking piece ( 60 ); the middle section of the shaft ( 20 ) and the pivot tube ( 12 ) are closely mated only when the second plain facet ( 23 ) and the first plain facet ( 13 ) are correspondingly matched up in rotation of the shaft ( 20 ) around the pivot tube ( 12 ); and the head end of the shaft ( 20 ) is inserted in the pivot tube ( 12 ) so that the middle section of the shaft ( 20 ) is received in the pivot tube ( 12 ) and the angular section ( 22 ) is exposed, whereafter the locking piece ( 60 ), the spring ( 40 ) and the ring ( 50 ) are sequentially mounted over the exposed angular section ( 22 ) of the shaft ( 20 ).