Anti-emission exhaust pipe joint and clamp therefor

A clamped joint comprising:

• A. a pair of pipes, each pipe having a rolled end forming a beaded formation directly thereon at an axial end thereof, said beaded formations including respectively axially facing flange surfaces and the flange surfaces being engaged in abutment on at least respective circular contact areas substantially coaxial with the pipes to dispose said beaded formations parallel and side by side,
• B. a pipe clamp formed of two generally semicircular halves each formed of a single piece of metal and having a semicircular medial portion and two ends extending respectively generally radially outwardly from the medial portions so that when the halves are mated to form a loop of the medial portions the juxtaposed ends will be generally parallel to one another at least where they connect with their respective medial portion,
• C. the medial portion of each half having an arcuate cross section throughout a substantial extent of its circumferential length arranged so that there are radially inwardly facing concave groove means on the interior of each half, the concave groove means straddling and engaging the beaded formations at locations spaced from their contact area to apply wedging forces if the halves are constricted which wedging forces tend to move the beaded formations toward one another to force the flange surfaces tightly into engagement,
• D. the first ends of each half being arranged on the same circumferential side of the loop resulting when the halves are mated and being generally planar and having cooperating tongue and slot means forming an articulated connection providing limited swinging movement of the halves relative to one another, said limited swinging movement being sufficient to expose the entire medial section, said swinging movement provided generally in a plane normal to the axis of said loop, the tongue means being integral with one first end and bent at an angle relative thereto toward the other first end, the slot means comprising a passageway through the other first end in a portion thereof which is planar and having a wide portion and a narrow portion to an edge of said other first end, the tongue means being engaged into the passageway and having an enlarged end protruding beyond the plane of the said other first end remote from the one first end, said tongue means being dimensioned to prevent withdrawal of said tongue means from said slot means, and
• E. the second ends of each half being arranged on the circumferential side of said loop diametrically opposite the first ends and being generally planar and having cooperating fastening means to bring said second ends together to constrict said halves on said beaded formations.