Echeloned torsion transmission and shock absorbing combined coupling

The invention provides an echeloned torsion transmission and shock absorbing combined coupling which comprises an input end half-coupling, a sheath, an elastic sleeve group, a middle joint, a variable-rigidity membrane group and an output end half-coupling. A flange of the input end half-coupling is connected with the sheath through the elastic sleeve group to form an elastic torsion transmission and impact absorbing loop. Outer teeth of the tail end of the input end half-coupling are matched with inner teeth of the sheath to form a torsion transmission strengthening loop. The front end of the middle joint is connected with the sheath, and the rear end of the middle joint is connected with the output end half-coupling through the variable-rigidity membrane group. By means of the echeloned torsion transmission and shock absorbing combined coupling, high-frequency torsion vibration of a diesel engine set, a reciprocating compressor unit and a frequency changer set can be effectively eliminated, and the problem that because the torsion is enlarged, connection and transmission of units become difficult in work of a chemical raw material gas compressor unit, an ethylene granulating machine group and the like is solved; and an optimal scheme is provided for long-distance transmission of a frequency-conversion renovation unit.