The present invention relates to a gear system with automatic operation designed to transmit the torque from the engine of an automotive vehicle to the driven wheels of the vehicle, in which changes in the vehicle speed is controlled as a function of the torque generated by the engine and of the linear momentum of the vehicle.

A control unit embedded in a work vehicle includes a clutch controlling unit and a motor controlling unit. The clutch controlling unit is configured to disengage a first clutch in a condition that the first clutch is engaged and a second clutch is disengaged, when a first moving direction inputted through a forward/rearward movement switch operating device as an instruction of the operator and a second moving direction determined based on a vehicle speed detected by a vehicle speed detecting unit are different from each other, and in addition, when and the vehicle speed falls in a preliminarily set first range. The motor controlling unit is configured to control a motor to reduce a relative rotational speed of the second clutch after the first clutch is disengaged.

A control unit embedded in a work vehicle includes a clutch controlling unit and a motor controlling unit. The clutch controlling unit is configured to disengage a first clutch in a condition that the first clutch is engaged and a second clutch is disengaged, when a first moving direction inputted through a forward/rearward movement switch operating device as an instruction of the operator and a second moving direction determined based on a vehicle speed detected by a vehicle speed detecting unit are different from each other, and in addition, when and the vehicle speed falls in a preliminarily set first range. The motor controlling unit is configured to control a motor to reduce a relative rotational speed of the second clutch after the first clutch is disengaged.

A planetary gear train of an automatic transmission for a vehicle may include an input shaft receiving torque of an engine, an output shaft outputting changed torque of the engine, a first planetary gear set including first, second, and third rotation elements, a second planetary gear set including fourth, fifth, and sixth rotation elements, a third planetary gear set including seventh, eighth, and ninth rotation elements, a fourth planetary gear set including tenth, eleventh, and twelfth rotation elements, and seven friction elements disposed to selectively connect the rotation elements with each other and selectively connect the rotation elements with a transmission housing.

A variable drive system of a power system is disclosed. The variable drive system may include an engine gearset to transfer power from an engine output of an engine to a variable input driveshaft of the variable drive system. The variable drive system may include a generator gearset to transfer power, generated by the engine, to a generator driveshaft of a generator. The variable drive system may include a variable drive, coupled to the variable input driveshaft, to enable a gear ratio between engine output and the generator driveshaft to be adjustable, the variable input driveshaft being offset from at least one of the engine output or the generator driveshaft. The variable drive system may include a direct drive clutch to bypass variable power transfer through the variable drive and enable direct power transfer from the engine output to the generator driveshaft.

A variable drive system of a power system is disclosed. The variable drive system may include an engine gearset to transfer power from an engine output of an engine to a variable input driveshaft of the variable drive system. The variable drive system may include a generator gearset to transfer power, generated by the engine, to a generator driveshaft of a generator. The variable drive system may include a variable drive, coupled to the variable input driveshaft, to enable a gear ratio between engine output and the generator driveshaft to be adjustable, the variable input driveshaft being offset from at least one of the engine output or the generator driveshaft. The variable drive system may include a direct drive clutch to bypass variable power transfer through the variable drive and enable direct power transfer from the engine output to the generator driveshaft.

A gearbox assembly for a gas turbine engine includes a planetary gear set comprising a sun gear, a planet gear, and a ring gear, the sun gear configured for connection to a first drive shaft of the gas turbine engine and the ring gear configured for connection to a second drive shaft of the gas turbine engine, and an electric machine assembly comprising an input and an electric machine. The electric machine comprising a rotor coupled to the input and a stator fixedly positioned within the gearbox assembly, the input of the electric machine assembly coupled to one of the sun gear, the ring gear, or the planet gear of the planetary gear set.

An eccentric oscillation gear device according to the disclosure includes: a casing; a first member supported by the casing via a first bearing; a second member supported by the casing via a second bearing; and a fastening portion fastening the first member and the second member to each other in an axial direction of the casing. The fastening portion includes an externally threaded portion and an internally threaded portion. At least one selected from the group consisting of feet of threads of the externally threaded portion and roots of threads of the internally threaded portion has elasticity portions for facilitating elastic deformation of the threads associated with the elasticity portions when the externally threaded portion and the internally threaded portion are tightened to each other.

An eccentric oscillation gear device according to the disclosure includes: a casing; a first member supported by the casing via a first bearing; a second member supported by the casing via a second bearing; and a fastening portion fastening the first member and the second member to each other in an axial direction of the casing. The fastening portion includes an externally threaded portion and an internally threaded portion. At least one selected from the group consisting of feet of threads of the externally threaded portion and roots of threads of the internally threaded portion has elasticity portions for facilitating elastic deformation of the threads associated with the elasticity portions when the externally threaded portion and the internally threaded portion are tightened to each other.

An automatic transmission includes a second planetary gear mechanism having a sun gear, a carrier, and a ring gear being defined as first, second and third elements, respectively, when a single pinion type planetary gear mechanism is applied; the carrier, the ring gear, and the sun gear being defined as the first, second, and third elements, respectively, when a double pinion type is applied; a first brake, a switching clutch being switchable to a first position where the third element is selectively fixed to a housing; a first clutch, a second clutch, a third clutch, and a fourth clutch. The first brake fixes a sun gear of a first planetary gear mechanism to the housing, the switching clutch fixes the third element to the housing, and the fourth clutch connects the second element to a carrier of the third planetary gear mechanism when establishing a reverse speed stage.