Component Description

Automatic Transmission - DPS6

Component Description

Clutch and Actuator Mechanism









The clutch and actuator sub - system consists of engine crankshaft mounted rotating components. These include, a center flywheel, odd and even clutch pressure plates, clutch actuating mechanisms and engagement components. The clutch actuators are independent systems within the clutch housing that apply an axial force to the clutch diaphragm springs causing their respective clutch to apply. This apply force is reacted back into the transaxle through the input shaft unlike a manual transaxle dry clutch system, no thrust is applied to the engine crankshaft. Normally the clutch capacity commands are mutually exclusive (to prevent tie-up) with minor overlaps to allow synchronous shifting. A clutch "touch point" position must be established by a learning algorithm within the system software. Establishing the touch point is the system's method for ensuring that the displacement-based clutch actuation system is properly calibrated. This is necessary so that the clutch capacity can be controlled correctly by the TCM and be engaged and released to the required torque capacity and within the required time.

Differential









The output shaft system consists of the output shaft gears, differential ring (final drive) gear and the differential assembly. Typically when a vehicle is traveling down the road both wheels are rotating at the same speed; however, when a vehicle is turning, the outside wheel must travel a greater distance than the inside wheel. To do this, in the same time, the outside wheel must rotate faster than the inside wheel. The differential is designed to provide speed compensation for the wheels to allow the vehicle to negotiate turns smoothly.

Shift Fork Mechanism









The shift system consists of two independent sub-systems for controlling the transaxle synchronizer pre - selections and engagements. Using this arrangement provides an independent control of the two transaxles and a mechanical interlock that prevents two gears within the same transaxle from being engaged simultaneously. The TCM (Transmission Control Module) houses two electric motors that mesh with and drive the first double gear wheel, which drives the second double gear which finally drives the shift drum. Gearing between the shift motors and the drums reduce speed and multiply torque. Position sensors in the TCM (Transmission Control Module) detect feedback of the motor angular position. Shift drum position is learned by the TCM (Transmission Control Module) during a teach-in process that involves rotating each drum against hard stops located on the shift drum and the transaxle housing.

Synchronizers




















As in manual transaxle operation, gear pre-selection is made by sliding the synchronizer sleeve towards a speed gear. This causes the internal splines of the synchronizer sleeve to bridge a gap between the output hub and the external spline feature of the speed gear, thus transmitting speed and torque between the gear and output shaft. Synchronizers are small cone wet friction clutches mounted to the transaxle output shaft. They are used to bring the rotation speed of the engaging speed gear in sync with the output shaft speed. After synchronous speed has been attained the final power flow connection is made possible and the synchronizer sleeve is permitted to pass by and engage the external spline teeth on the speed gear.