Flexible expansion pipe joint

Claim 1

AN EXPANSION JOINT FOR CONNECTING SPACED CONDUIT SECTIONS OF RECTANGULAR CROSS-SECTIONAL FLOW CONFIGURATION AND HAVING A SUBSTANTIALLY COMMON AXIS, SAID JOINT HAVING SUBSTANTIALLY THE SAME CONFIGURATION AS SAID CONDUIT SECTIONS AND COMPRISING A PLURALITY OF SIDE AND CORNER PORTIONS JOINED IN EDGE RELATION TO SURROUND THE SPACE BETWEEN SAID SPACED CONDUIT SECTIONS, EACH OF SAID EXPANSION JOINT PORTIONS BEING FORMED BY SPACED LEAF MEMBERS POSITIONED GENERALLY PERPENDICULARLY TO THE SUBSTANTIALLY COMMON AXIS OF SAID SPACED CONDUIT SECTIONS, EACH OF SAID LEAG MEMBERS BEING CONNECTED ON ITS OUTER PERIPHERY TO ONE ADJACENT LEAF MEMBER AND ON ITS INNER PERIPHERY TO THE OTHER ADJACENT LEAF MEMBER BY PLATES ARRANGED PARALLEL TO SAID COMMON AXIS, THE CORNER PORTIONS OF SAID EXPANSION JOINT HAVING THEIR LEAF MEMBERS CURVED ON THEIR INNER PERIPHERIES, THE PLATES CONNECTING THE INNER PERIPHERIES OF ALTERNATE CORNER LEAF MEMBERS BEING CORRESPONDINGLY CURVED, THE OUTER PERIPHERIES OF EACH CORNER PORTION LEAF MEMBER HAVING A RIGHT ANGLED CORNER, AND THE PLATES CONNECTING THE OUTER PERIPHERIES OF ALTERNATE CORNER PORTION LEAF MEMBERS BEING CORRESPONDINGLY RIGHT ANGLED TO PROVIDE AN INCREASED DEPTH OF SAID LEAF MEMBERS IN SAID CORNER PORTIONS TO THEREBY INCREASE THE FLEXURE STRENGTH OF THE CORNER LEAF MEMBERS.