Apparatus and method for stretching the links of a transmission chain while surpassing the limit of elasticity thereof

An endless transmission chain stretching apparatus which surpasses the limit of elasticity of a chain to be stretched, said chain comprising links intercoupled by rocker pins, said apparatus comprising:

• a first pair and a second pair of conical supporting surfaces for the ends of the rocker pins, resting thereon, while protruding outside the links of the transmission chain which is arranged there around, said surfaces being carried by rotatingly supported shafts with a controlled mutual distance, and a third pair of conical supporting surfaces carried by a third rotating shaft, cooperating with the first and second pair of surfaces in supporting a chain to be stretched, all three pairs of supporting surfaces having such a running radius and being positioned with respect to each other in such a way that said chain covers an arc over each of said supporting surfaces sufficient to ensure that the links of the chain experience, during their travel over said arc, an ensured and sufficient stretching loading of these areas thereof which undergo a heaviest loading during actual operation of said chain,
• in which the axes of the first and second shaft lie on respective vertexes of a first side of an imaginary, equilateral triangle while the axis of the third shaft lies on an adjustable distance from these axes on the vertexes of the second and third sides respectively of this triangle.