Constant-speed descent control device

The invention relates to a constant-speed descent control device. Rotating speed of a transmission part of the descent control device is controlled through a novel escapement mechanism, so that the purpose of human body descending at a constant speed is reached. The constant speed descent control device comprises a rope clipping wheel assembly, a planetary transmission gear train, an escapement mechanism assembly and auxiliary members such as an upper fixing plate and a lower fixing plate; and escapement gear teeth are isosceles triangles in the escapement mechanism, teeth number can vary within a range of 6-12, and the upper end and the lower end of a escapement gear are provided with rolling slip components. The constant speed descent control device is high in reliability, constant in speed of controlling human body descending, waterproof, oilproof and free of affections of various external environments in storage.