A transmission for an energy storage and recovery system is disclosed. A variable slip transmission and a clutch arranged to transmit drive while slipping. The level of torque transmitted through the slipping clutch is dependent on the clutch force but is independent of the clutch slip speed. Preferably the clutch is provided by a plurality of clutches connected in parallel in a range extender. When drive is transferred between clutches in parallel, the clutch forces of both clutches are controlled to maintain the total torque transmitted by the clutches. This reduces torque fluctuations at the energy source/sink during clutch transfer. Where there are two slipping clutches in series, one clutch is controlled to provide the required torque and the other clutch is controlled in response to a clutch slip speed. This helps to control the speed of rotation of the mass between the clutches.

A vehicle driveline and a method for synchronizing a flywheel and the vehicle driveline are provided. The vehicle driveline includes a power source, a primary clutch drivingly engaged with the power source, a primary transmission drivingly engaged with the primary clutch, a secondary transmission drivingly engaged with one of a portion of the primary clutch and an input of the primary transmission, a controller in communication with the secondary transmission, and a flywheel drivingly engaged with the secondary transmission. The vehicle driveline facilitates a transfer of energy to and from the flywheel based on at least one of a state of charge of the flywheel, a power requirement of the vehicle driveline, and a state of operation of the power source.

The present invention relates to methods of controlling kinetic energy recovery systems (KERS), to controllers, KERS, drivetrains and vehicles including the KERS and controllers. The KERS comprises an energy storage system. In an embodiment, a vehicle is provided with a first vehicle operating mode wherein the energy storage system has a first target state of charge, and with a second vehicle operating mode wherein the energy storage system has a second target state of charge. The first or second vehicle operating mode is selected and energy is transferred between the energy storage system and the vehicle in order to achieve the target state of charge associated with the selected vehicle operating mode. In other embodiments, the KERS includes a variable power transmission device adapted to transfer energy to and from the energy storage system. The energy storage system is maintained at suitable energy levels for the vehicle's driving conditions.

An energy storage device is mounted at a horizontal end of a work vehicle for storing energy generated from operation of the work vehicle. The energy storage device includes a stator of an electric machine having a stator axis, a rotor of the electric machine fixed for rotation with a rotating ballast and configured for rotation about the stator axis, a housing disposed around the rotor and configured to contain the electric machine, and a brake configured to absorb kinetic energy of the rotor.

A work vehicle and energy storage device include an electric machine having a stator and a rotor. The rotor is configured to rotate from the flow of electrical current provided to the electric machine, rotate to store energy of the work vehicle, provide a rotor mass to an end of the work vehicle, and generate electrical current for the work vehicle from rotation of the rotor. The rotor mass is greater than a stator mass.

A hybrid vehicle comprises an internal combustion engine, a transmission, at least one driving wheel rotationally connected to the transmission, and a coupling arrangement arranged between the internal combustion engine and the transmission, and controllable between a first state in which a drive shaft of the engine is rotationally connected to the transmission and a second state in which the drive shaft of the engine is rotationally disconnected from the transmission. The vehicle further comprises an energy recovery device connected to the coupling arrangement via a flexible driving member for allowing recovery and storage of energy recovered from deceleration of the at least one driving wheel. The vehicle may further comprise a sensor for sensing a parameter value indicative of desired deceleration, and a control unit for controlling the coupling arrangement to the second state when the sensed parameter value indicates desired deceleration of the hybrid vehicle.

A driveline for a vehicle is provided. The driveline includes a power source, a planetary gearset, a lockout clutch, a transmission, and a kinetic energy recovery system. The planetary gearset includes a sun gear, a carrier having a plurality of planet gears rotatably disposed thereon, and a ring gear. The power source is in driving engagement with a portion of the planetary gearset. The lockout clutch is capable of placing the planetary gearset in a locked out condition. The transmission is in driving engagement with another portion of the planetary gearset. The kinetic energy recovery system includes an accessory clutch and a flywheel. The accessory clutch facilitates driving engagement between the flywheel and another portion of the planetary gearset. The lockout clutch and the accessory clutch are selectively engaged to facilitate a transfer of energy to and from the transmission and the flywheel.

A vehicle driveline and a method for synchronizing a flywheel and the vehicle driveline are provided. The vehicle driveline includes a power source, a primary clutch drivingly engaged with the power source, a primary transmission drivingly engaged with the primary clutch, a secondary transmission drivingly engaged with one of a portion of the primary clutch and an input of the primary transmission, a controller in communication with the secondary transmission, and a flywheel drivingly engaged with the secondary transmission. The vehicle driveline facilitates a transfer of energy to and from the flywheel based on at least one of a state of charge of the flywheel, a power requirement of the vehicle driveline, and a state of operation of the power source.

This invention relates to a method and arrangement for reduction of rotational mass of transmission system of a vehicle to improve its fuel efficiency. The reduction of rotational mass is achieved by replacing the torque converter of an automatic transmission or conventional clutch system of a manual transmission, by a flywheel and a holding device. The flywheel and the holding device are located inside the bell housing of the transmission.

A working vehicle includes an engine, a first flywheel to rotate upon receipt of rotational power of the engine, a transmission to selectively receive rotational power of the engine or rotational power of the engine and the first flywheel, speed-change the received rotational power, and output the speed-changed rotational power, a first power transmission path to transmit the rotational power of the engine to the first flywheel, and a second power transmission path to transmit the rotational power of the first flywheel to the transmission. The first and second power transmission paths are independent of each other. The first power transmission path includes a first clutch to selectively allow or interrupt transmission of rotational power from the engine to the first flywheel. The second power transmission path includes a second clutch to selectively allow or interrupt transmission of rotational power from the first flywheel to the transmission.