Clamp assembly with tubular saddle member

Claim 1

A clamp assembly for effecting a substantially gas-tight connection between two thin-walled tubes such as exhaust system parts or the like having end portions disposed in telescoping relation comprising a U-bolt having a bight portion defining a semi-circular inner peripheral surface of a size to engage in an operative position the upper exterior periphery of the outer tube end portion and a pair of legs extending tangentially therefrom in parallel relation, said legs being of circular cross-section and having the exterior periphery thereof adjacent the free end portions thereof threaded, nut means for threadedly engaging the threaded free end portion of each of said U-bolt legs, and a saddle member in the form of a rigid tubular sheet metal structure including a pair of U-bolt leg receiving end sections and a central tube engaging section rigidly interconnecting said end sections, each of said end sections including vertically extending wall means defining a vertically extending channel closed along its sides and outer end and opened along its inner end for receiving in generally loosely confined relation a leg of said U-bolt, the wall means of each end section including spaced end wall portions defining the open inner end portion of the associated channel, said central section consisting of a pair of generally horizontally spaced vertically extending side walls rigidly joined with corresponding end wall portions of said end sections and extending therebetween with a horizontal extent generally equal to the diameter of the interior tube engaging surface of said U-bolt bight portion, the upper portion of said side walls and the upper portion of said end wall portions being planar and providing a pair of upper concavely arcuate tube engaging parallel edges spaced apart a distance slightly grEater than the diameter of the legs of said U-bolt, each of said arcuate edges having a radius generally equal to the radius of the interior surface of said U-bolt bight portion and an arcuate extent of at least approximately 180*, said end sections providing downwardly facing edges disposed in a flat horizontal plane for receiving the upward forces applied by threadedly engaging said nut means on said U-bolt legs with the bight portion thereof in engagement with the upper periphery of the outer tube and the tube engaging edges of said saddle member in engagement with the lower periphery of the outer tube, which upward forces oppose the downward forces applied to said U-bolt thereby, the vertical extent of said side walls being smallest at the mid-portions thereof and increasing therefrom toward both of said end sections so that the upward forces applied to said end sections when said clamp is engaged as aforesaid will effect a horizontal inward deflection of said side walls substantially within their elastic limit which is maximum adjacent the junctions of the upper tube engaging edges thereof with said end sections and decreases to a minimum adjacent the mid-portions thereof so as to insure radially inward clamping pressure on said tubes throughout the entire exterior periphery thereof.