Plastic bellows elbow with spigot and socket ends

Claim 1

AN ELBOW FOR CONNECTING AN EAVESTROUGH TO A DOWNSPOUT WHEREIN THE EAVESTROUGH HAS A COUPLING OF RECTANGULAR CROSS SECTION CONNECTED THERETO, SAID ELBOW COMPRISING AN UPPER PORTION FOR TELESCOPIC ENGAGEMENT OVER THE OUTSIDE OF SAID COUPLING AND BEING COMPRISED OF A PLASTIC HAVING LIMITED FLEXIBILITY AND A TENDENCY TO COLD FLOW TO A PREDETERMINED SET UNDER SUSTAINED PRESSURE AND HAVING AN ELASTIC MEMORY, SUCH AS TO CAUSE IT TO RETURN TO ITS ORIGINAL CONFORMATION UPON RELEASE OF PRESSURE AND THE ABILITY TO CONTRACT AND FORM A CLOSE WEATHERPROOF SEAL, SUCH AS POLYVINYL CHLORIDE AND HAVING AN UPPER PORTION WHICH IS SUBSTANTIALLY RECTANGULAR IN CROSS SECTION AND OF A LENGTH SUBSTANTIALLY THAT OF THE COUPLING ON THE EAVESTROUGH AND BEING OF INCREASING DIAMETER TOWARD ITS UPPER END, TWO OPPOSITE SIDES OF SAID WALLS BEING FORMED WITH AN OUTWARDLY EXTENDING PORTION ARRANGED TO BE DISTORTED ON APPLICATION AND THE TWO ADJACENT SIDES BEING FORMED WITH A MEDIAN ZONE WHICH GRADUALLY INCREASES IN DIAMETER TOWARD THE MID-LINE OF THE WALL TO PROVIDE AN