Sofa bed hinges

Claim 1

A SOFA BED HINGE FOR SUPPORTING SEAT AND BACK FRAMES ON THE BASE OF A SOFA BED FOR MOVEMENT OF THE FRAMES BETWEEN A SEAT POSITION WITH THE SEAT FRAME RESTING ON THE BASE AND THE BACK FRAME ANGULARLY DISPOSED THERETO AT A NORMAL SEATING ANGLE, AN INTERMEDIATE POSITION WITH THE BACK FRAME RESTING ON THE BASE AND THE SEAT FRAME ANGULARLY DISPOSED THERETO AT THE SEATING ANGLE AND A BED POSITION WITH BOTH FRAMES RESTING ON THE BASE, SAID HINGE COMPRISING: A PAIR OF HINGE PLATES RESPECTIVELY ADAPTED FOR AFFIXING TO THE FRAMES, A PIVOT CONNECTING SAID HINGE PLATES TOGETHER FOR RELATIVE ROTATIONAL MOVEMENT BETWEEN THE BED POSITION AND A TRIP POSITION IN WHICH THE FRAME INCLUDE AN ANGLE LESS THAN THE NORMAL SEATING ANGLE, MEANS FOR PIVOTALLY MOUNTING SAID PLATES TO THE BASE FOR PIVOTAL MOVEMENT BETWEEN THE SEAT AND INTERMEDIATE POSITION, A LATCH ENGAGING ELEMENT ON ONE OF SAID PLATES, A LATCH, AND COUPLING MEANS FOR CONNECTING SAID LATCH WITH THE OTHER OF SAID HINGE PLATES FOR ROTATIONAL MOVEMENT AND LIMITED TRANSLATIONAL MOVEMENT OF THE LATCH RELATIVE TO SAID OTHER HINGE PLATE IN MOVING BETWEEN AN EXTENDED POSITION IN WHICH SAID LATCH CONTACTS SAID ENGAGING ELEMENT WHEN SAID HINGE PLATES ARE IN THE TRIP POSITION AND A RETRACTED POSITION IN WHICH SAID LATCH ENGAGES SAID ENGAGING ELEMENT WHEN SAID HINGE PLATES ARE IN THE INTERMEDIATE POSITION BUT SAID LATCH DOES NOT CONTACT SAID ENGAGING ELEMENT WHEN SAID HINGE PLATES ARE IN THE TRIP POSITION, SAID LATCH IN THE EXTENDED POSITION CONTACTNG SAID ENGAGING ELEMENT AND PIVOTING ABOUT SAID COUPLING MEANS WHEN SAID HINGE PLATES ARE ROTATED RELATIVE TO ONE ANOTHER IN MOVING FROM THE BED POSITION TO THE TRIP POSITION, SAID LATCH BEING SHIFTED FROM THE EXTENDED TO THE RETRACTED POSITION BY SAID ENGAGING ELEMENT WHEN SAID HINGE PLATES ARE ROTATED RELATIVE TO ONE ANOTHER IN MOVING FROM THE TRIP TO THE INTERMEDIATE POSITION, WHEREBY SAID LATCH IS COMPRESSIVELY JAMMED BETWEEN SAID COUPLING MEANS AND SAID ENGAGING ELEMENT TO ESTABLISH A RIGID CONNECTION BETWEEN SAID HINGE PLATES AND PREVENT SAID PLATES ROTATING RELATIVE TO ONE ANOTHER WHEN PIVOTED ABOUT SAID PIVOTAL MOUNTNG MEANS BETWEEN THE INTERMEDIATE AND SEAT POSITION, SAID LATCH IN THE RETRACTED POSITION BEING RELEASED FROM SAID ENGAGING ELEMENT WHEN SAID HINGE PLATES ARE ROTATED RELATIVE TO ONE ANOTHER TO THE TRIP POSITION AFTER SAID HINGE PLATES ARE PIVOTED ABOUT SAID PIVOTAL MOUNTING MEANS FROM THE SEAT TO THE INTERMEDIATE POSITION, WHEREBY SAID HINGE PLATES MAY BE ROTATED RELATIVE TO ONE ANOTHER FROM THE TRIP TO THE BED POSITION.