Multi-Speed EV Transmission Layout for Compact Dual-Range Shifting

The patent repositions the high and low torque transmitting mechanisms from a coaxial arrangement to a non-coaxial arrangement where they share a common output shaft but are positioned at different locations along the shaft. This spatial reconfiguration reduces the transmission's length in the axial direction while maintaining the ability to handle varying torque demands through selective engagement of different mechanisms.

The patent segments the power transmission path by introducing separate high torque and low torque transmitting mechanisms that can be selectively engaged. This segmentation allows the transmission to provide different gear reduction ratios suitable for electric drive applications while maintaining a relatively simple overall structure. The high torque mechanism provides significant gear reduction for low-speed high-torque operation, while the low torque mechanism provides moderate gear reduction for higher-speed operation.

The patent employs a dynamic configuration where the high and low torque transmitting mechanisms can be selectively engaged based on operating conditions. The high torque mechanism with larger gears and shafts is engaged during high-torque, lower-speed operations to provide adequate power transmission capability. The low torque mechanism with smaller, lighter components is engaged during lower-torque, higher-speed operations, thereby reducing the operational speeds and loads on the gear train and improving transmission longevity.