Hinge mechanism

Claim 1

MEANS FOR DETACHABLY MOUNTING A HINGED MEMBER TO A SUPPORT FOR PIVOTAL MOVEMENT ABOUT A HORIZONTAL HINGE LINE COMPRISING A HINGE PLATE PIVOTALLY CONNECTED TO THE HINGED MEMBER AND EXTENDING THEREFROM IN A DIRECTION TRANSVERSE TO SAID HINGE LINE, THE HINGE PLATE LYING IN A SUBSTANTIALLY VERTICAL PLANE, A LOCKING ABUTMENT PROJECTING FROM THE LOWER EDGE OF THE HINGE PLATE, A MOVABLE CATCH MEMBER MOUNTED ON THE HINGE PLATE, AND A RETAINING SOCKET RIGIDLY MOUNTED ON THE SUPPORT FOR RECEIVING AND RELEASABLY SECURING THE HINGE PLATE, THE RETAINING SOCKET COMPRISING A HORIZONTALLY MOUNTED CHANNEL-SHAPED MEMBER HAVING UPPER AND LOWE EDGES AND PROVIDING A VERTICALLY ELONGATED ENTRY APERTURE FOR THE HINGED BLADE, SAID LOWER EDGE PROVIDING A LOCKING APERTURE POSITIONED TO ENGAGE SAID LOCKING ABUTMENT AND SAID UPPER EDGE CARRYING A VERTICAL FLANGE WITH A HORIZONTAL LOWER EDGE COOPERATING WITH SAID MOVABLE CATCH MEMBER, SAID CATCH MEMBER BEING MOVABLE BETWEEN A FIRST POSITION AT WHICH IT ENGAGES THE LOWER EDGE OF SAID VERTICAL FLANGE WHEREBY TO PREVENT LIFTING OF THE LOCKING ABUTMENT OUT OF THE LOCKING APERTURE AND A SECOND POSITION AT WHICH IT IS DISENENGAGE FROM SAID LOWER EDGE WHEREBY TO PERMIT LIFTING OF THE LOCKING ABUTMENT FROM THE LOCKING APERTURE AND HENCE REMOVAL OF THE HINGED MEMBER FROM THE SUPPORT.