Device for stretching a transmission chain

A device for stretching a continuous transmission chain having a number of adjacent links which are, as seen in the longitudinal direction of the chain, mutually coupled by pairs of elongated rocker elements, each rocker element having two ends, wherein for each pair of rocker elements, the ends of at least one rocker element cooperate in a torque transferring way with a pulley sheave of a pulley sheave transmission, comprising:

• a first and a second supporting surface, each surface supporting a chain to be stretched over a part of an arc, wherein the distance between the first and second supporting surface is adjustable in such a way that in a chain which supported thereby, a tensile stress can be generated that locally exceeds a limit of elasticity of the material of the links,
• a frame having two arms which lie at a distance from each other, wherein the first supporting surface is freely rotatably accommodated between the arms at a first end of the frame,
• an auxiliary carrier accommodated between the two arms and supported by two stubby shafts, each protruding at a surface of the auxiliary carrier, wherein the second supporting surface is freely rotatable around the auxiliary carrier and an axis of rotation of the stubby shafts lies at a distance from an axis of rotation of said second supporting surface, said stubby shafts being rotatably supported between the arms near a second end of the frame while at least one of said shafts is coupled to the auxiliary carrier and can be driven in rotation therewith.