Patent ID: 6704418
Filing Date: 2004-03-09
Classification: E05D,E05Y,H04M,Y10T

Abstract:
A hinge device for connecting a device body with its cover rotatably between closed and open positions, comprising:a pair of hinge members which are connected with said device body and said cover respectively and which are connected such that they can rotate with respect to each other about a rotational axis of said device body and said cover; a movable member which is connected with one of a pair of hinge members non-rotatably and which can move in the direction of said rotational axis; a biasing mechanism which presses said movable member against the other hinge member; said other hinge member and said movable member having contact faces which come into contact with each other; a pair of first conversion portions on one of said contact faces which are separated by 180 degrees from each other in a circumferential direction about said rotational axis; a pair of second conversion portions on the one of said contact faces which are separated by 180 degrees from each other in a circumferential direction about the said rotational axis and which are separated by a predetermined angle from said first conversion portions in a circumferential direction, a pair of positioning cavity cavities on the one of said contact faces which are arranged at a center within the predetermined angle of separation between said pairs of first and second conversion portions; a pair of pressing projections on the other of said contact faces, the pair of pressing projections being separated by 180 degrees from each other in a circumferential direction about said rotational axis; the pair of said pressing projections coming into contact with the pair of said first conversion portions to convert the force of said biasing mechanism into a force for pressing said other hinge member from its open position toward its closed position when the cover is located at its closed position; the pair of said pressing projections coming into contact with the pair of said second conversion portions to convert the force of said biasing mechanism into a force for pressing said other hinge member from its closed position toward its open position when the cover is located at its open position; the pair of said pressing projections fitting into the pair of said positioning cavities to connect the pair of said hinge members with each other by resisting further relative rotation of the other hinge member; a bottom face defining of each of said positioning cavities being formed on the one of said contact faces by a concave spherical surface; and an outer face of each of said pressing projections being formed by a convex spherical surface having the same size of that of the concave spherical surface of said positioning cavities.