Patent ID: 6978692
Filing Date: 2005-12-27
Classification: F16D,F16H,Y10T

Abstract:
1. Automatic transmission device with torque transfer, intended to connect a driving shaft ( 10 ) and a driven shaft ( 12 ) and comprising an input shaft ( 18 ), driving pinions ( 20 ) mounted on the input shaft, driven pinions ( 22 ) mounted on the driven shaft ( 12 ), each driving pinion being constantly in engagement with a driven pinion ( 22 ) and defining a transmission ratio, one of the pinions of each ratio being rotationally fixed to its shaft and the other being free to rotate on its shaft, at least one clutch (E 2 ) connecting the driving pinion of the last transmission ratio to the input shaft ( 18 ), and means of selective connection of each free pinion and its shaft for the engagement of the corresponding transmission ratio, comprising, for at least one free pinion, two controlled unidirectional locking mechanisms ( 24 ), mounted in opposite directions between the free pinion ( 22 ) and its shaft ( 12 ) in order to prevent a speed of rotation of the free pinion which is lower or respectively higher than the speed of rotation of its shaft ( 12 ) and each being able to occupy two positions, one idle and the other service, wherein the locking mechanisms ( 24 ) are associated with mechanical actuation means comprising at least one cam ( 26 ) able to be moved in translation and/or rotation which acts positively on the said mechanisms in order to bring them into the service position, and means ( 32 ) of controlling the actuation means ( 26 , 28 , 30 ) and the clutch (E 2 ) for controlling the speed of rotation of the input shaft ( 18 ) according to the change in transmission ratio to be effected, the change in ratio comprising a step of passing from an initial state in which a ratio is engaged, to an intermediate state in which the free pinion of the engaged ratio and the free pinion of the ratio to be engaged each have a mechanism for locking in the service position and a mechanism for locking in the idle position, a step of passing from this intermediate state to a final state in which the mechanisms for locking the free pinion of the ratio to be engaged are in the service position and those of the free pinion of the previously engaged ratio are in the idle position, and a step of controlling the clutch (E 2 ) which takes place between the initial state and the final state.