Abstract: A gas generator comprises a housing accommodating a combustion chamber with a hollow solid-reactant charge, and a cooling chamber with a solid sublimating coolant, separated by a partition with an axial passage, and a sleeve with a perforated side surface. The gas generator is also provided with guides secured in the axial passage of the partition. The sleeve having a collar on the side of the open portion is disposed in the guides and adapted to move along the longitudinal axis of the gas generator. The present invention makes it possible to improve the operational reliability of power drives and offers a most simple solution to a number of problems associated with inflation of inflatable life-saving appliances, lifting of loads from under water, starting of engines.