Multi-tubular truss joint and method of joining tube ends

A multiple tubular structure comprising a plurality of elongated hollow tubes each having a partially flattened end portion with an elongated annular cross-sectional contour shape wider than the contour of the central portion of the tube, the height dimension of the crosssectional contour of each said tube flattened end portion being substantially less than the width dimension, said end portion height dimensions of said plurality of said tubes varying from each other to the degree that segments of said flattened end portions of each of said plurality of tubes can be telescopically fitted into a mutually nesting relationship, said plurality of tubes being arranged into an array of mutually nesting flattened tube end portions in which segments of each said flattened end portion of each of said plurality of tubes are in a telescopically nesting relationship, a splice plate having an upper surface and a lower surface of which corresponding segments in different portions of said plate are separated by different distances, said splice plate extending interiorly of said array of telescopically nested flattened tube end portions with said splice plate upper and lower surface segments, respectively, in overlapping contact with upper and lower interior surfaces of the flattened end portions of each of said plurality of tubes, and a plurality of fixed fastening means at spaced intervals in contact with opposite exterior surfaces of each said tube flattened end portion of said array and penetrating through each said tube flattened end portion of said array and said splice plate contained therewithin for permanently clamping together said splice plate and said array of nesting, flattened tube end portions into an integral mechanical joint.

A tubular structural joint for a multiple tube structure having a first plurality of hollow tubes arranged in angular relationship to one another in one plane with the longitudinal axes of said first plurality of tubes intersecting at a node of said multiple tube structure and a second plurality of hollow tubes arranged in an angular relationship to one another in a second plane with the longitudinal axis of said second plurality of tubes intersecting at said node, said joint comprising end portions of each of said first plurality of tubes flattened into an elongated annular contour and angularly arranged with segments of the tube flattened ends of each of said first plurality of tubes mutually overlying in a telescopically nesting relationship, a first variable thickness splice plate having upper and lower surfaces of which corresponding segments in different portions of said plate have different separations, said splice plate extending interiorly of the flattened ends of each of said first plurality of tubes with segments of opposite surfaces of said splice plate in overlapping contact with interior surfaces of the tube flattened ends of each of said first plurality of tubes, end portions of each of said second plurality of tubes flattened into an elongated annular contour and angularly arranged with segments of the tube flattened end of each of said second plurality of tubes mutually overlying in a telescopically nesting relationship, a second variable thickness splice plate having upper and lower surfaces of which corresponding segments in different portions of said second plate have different separations, said second splice plate extending interiorly of the flattened end of each of said second plurality of tubes with segments of opposite surfaces of said second splice plate in overlapping contact with interior surfaces of the tube flattened ends of each of said second plurality of tubes, an upper bracket having a first section in an overlying contacting relation to an upper surface of each tube flattened end portion of said first plurality of tubes and a second section in an overlying contacting relation to one surface of each tube portion flattened end portion of said second plurality of tubes, a lower bracket having a first section in an overlying contacting relation to a lower surface of each tube flattened end portion of said first plurality of tubes and a second section in an overlying, contacting relation to said one surface of each tube flattened end portion of said second plurality of tubes, and a plurality of spaced apart fastening means in fixed clamping contact with the exterior surfaces of each one of said first and second sections of each said upper and lower bracket, said fastening means transversely penetrating said brackets and said flattened end portions of said first and second plurality of tubes and said splice plates contained therewithin.

A method of joining together the ends of a plurality of elongated tubes comprising the steps of compressing diametrically opposite walls of an end portion of each said tube sufficiently to flatten the shape of an endmost segment of each said end portion into an elongated, oval annulus having a width dimension greater than the central portion of the tube and a height dimension substantially less than said width dimension, said height dimension of the end of each tube end portion varying from each other as will permit segments of each said flattened end portion of each of said plurality to tubes to be telescopically fitted into a mutually nesting relationship, arranging said hollow tubes into an array in which the tube longitudinal axes are coplanar and intersect at a common point with said segments of the flattened end portions of each of said plurality of tubes in a mutually telescopically nesting relationship, inserting a segmental splice plate of which each segment has upper and lower surfaces separated by said different height dimension of each of said tube end portions into the interior of said array of tube end portions with the upper and lower surfaces of each of said splice plate segment in overlapping contact with an interior surface of each said tube flattened end portion of said plurality of tubes, and inserting fastening means to pass transversely of each said tube flattened end portion and splice plate contained therewith with opposite ends of each fastening means in fixed clamping contact with opposite sides of each said tube flattened end portion.

A structural joint comprising end portions of a plurality of hollow cylindrical tubes partially flattened into an elongated annular shape, said tube flattened end portions each having upper and lower interior facing surfaces, said upper and lower interior surfaces of each said flattened end portion separated by different distances, said plurality of tube flattened end portions being angularly arranged such that fractional portions of each of said tube flattened portions are in a mutually telescopically nesting and contacting relationship with the longitudinal axes of said plurality of tubes intersecting at the joint, a variable thickness splice plate having upper and lower exterior surfaces of which corresponding segments in different portions of said plate are separated by different distances, said splice plate being positioned interiorly of said plurality of angularly arranged flattened tube end portions with all portions of said splice plate upper and lower exterior surfaces in overlapping contact with upper and lower interior facing surfaces of each said tube telescopically nesting fractional end portion and major portions of the remainder of said tube flattened end portion upper and lower facing surfaces other than said telescopically nesting fractional tube flattened end portions, and a plurality of fastening means in contact with exterior surfaces of and transversely penetrating each said telescopically nesting fractional tube flattened end portion and each of said remainder of tube flattened end portions other than said telescopically nesting fractional tube flattened end portions and said splice plate contained with said plurality of tube flattened end portions.