A novel load-sensitive dual-speed transmission (LSDT), which can shift self-adaptively according to load, is proposed. It is applicable to a common condition, which is that the actuator of a machine has a long no-load stroke before it encounters load, but when it is loaded, it has to satisfy the demand of big torque. The LSDT consists of a planetary gear train, an overrunning clutch, and a torque limiter (TL) and so on. It can self-adaptively switch gears according to whether the magnitude of load exceeds a preset value of the TL with a wide speed range, which is realized by its mechanical structure not by sensors and complex control system. A design example of the LSDT is carried out simulated in virtual simulation platform. The LSDT model is simulated in two situations in which the mechanism of the LSDT is driven manually and driven by motor. The simulation results show that the LSDT is effective and has a potential application.
