Self-contained modular joint, notably for robots

Self-contained modular joint adapted to interconnect two machine elements to permit a relative rotation of less than one revolution therebetween, wherein the first element comprises a strap consisting of a pair of wing-like extensions encompassing the second element in such a manner that said second element can pivot between said two wing extensions, each wing extension of said strap being provided with a bore concentric to the axis of said relative rotation, said bore being adapted to be engaged by first and second members of revolution each adapted to center and position in the axial direction an inner race of rolling contact bearings capable of absorbing axial and radial efforts, the outer race of each one of said bearings being carried by third and fourth members of revolution centered and secured to said second element so as to constitute between said two elements a joint free of both axial and radial play, wherein one of said third and fourth members of revolution secured to said second element has fitted thereon a toothed annulus of a reduction gearing assembly and wherein another element of said reduction gearing assembly comprises a flexible toothed ring which is secured to one of said first and second members of revolution rigid with the wing extension of said strap which is opposite said one of said third and fourth members of revolution rigid with said second element having said annulus secured thereto, said joint being further characterized in that said one of said first and second members of revolution also supports a control motor having a drive shaft mechanically connected to said reduction gearing assembly so as to drive said reduction gearing in such a manner that all the essential component elements of the joint are distributed along the axis of rotation about which one machine element can pivot in relation to the other element to an extent of less than one revolution.