The statements in this section merely provide background information related to the present disclosure and may or may not constitute prior art.
A typical multi-speed automatic or hybrid transmission uses a combination of torque transmitting devices, such as clutches or brakes, to achieve a plurality of forward and reverse gear or speed ratios. Selection of speed ratios is typically accomplished by a microprocessor transmission control module that employs various vehicle parameters, for example vehicle speed, and various driver input signals, for example accelerator pedal position, to select the appropriate speed ratios. The transmission then engages a combination of the toque transmitting devices to provide the desired speed ratios.
These torque transmitting devices generally include plate clutches or dog clutches typically used in manual transmissions. Plate clutches are typically designed for sufficient torque capacity for all engaged operating conditions of the transmission and are accordingly robust. However, typical plate clutches often require substantial packaging space and may create problems with smooth engagement under light torque loads and can also contribute to substantial spin losses. In contrast, dog clutches have near zero spin losses but cannot be used for power-on up-shifts due to lacking torque capacity prior to full engagement which yields an inability to absorb energy and synchronize speed before engagement. Accordingly, there is a need in the art for a torque transmitting assembly that combines the features of the plate clutch, e.g. able to provide power-on up-shifts, with the features of the dog clutch, e.g. minimized packaging, minimized spin loss, and robust torque capacity.
USPTO Backgrounds
USPTO Backgrounds