Various vehicle systems capable of different operation modes are disclosed. According to one example, the system can include at least one input shaft, at least one output shaft, a plurality of hydraulic devices, and one or more accessories. The plurality of hydraulic devices can be configured to be operable as vane pumps in a retracted vane mode of operation and can be configured to be operable as a hydraulic couplings to couple the at least one input shaft with the at least one output shaft in a vane extended mode of operation. The plurality of hydraulic devices can be simultaneously operable as the hydraulic couplings and the vane pumps. The one or more accessories can be in fluid communication with the plurality of hydraulic devices and can be configured to receive a hydraulic fluid pumped from one or more the plurality of hydraulic devices when operating as the vane pumps.

Various vehicle systems capable of different operation modes are disclosed. According to one example, the system can include at least one input shaft, at least one output shaft, a plurality of hydraulic devices, and one or more accessories. The plurality of hydraulic devices can be configured to be operable as vane pumps in a retracted vane mode of operation and can be configured to be operable as a hydraulic couplings to couple the at least one input shaft with the at least one output shaft in a vane extended mode of operation. The plurality of hydraulic devices can be simultaneously operable as the hydraulic couplings and the vane pumps. The one or more accessories can be in fluid communication with the plurality of hydraulic devices and can be configured to receive a hydraulic fluid pumped from one or more the plurality of hydraulic devices when operating as the vane pumps.

A road milling machine includes a machine frame, at least three travelling devices, a milling drum, and at least one hydraulic drive system. The hydraulic drive system includes at least one hydraulic pump, at least one hydraulic fixed displacement motor for driving at least one driven travelling device, and one each hydraulic variable displacement motor for driving the remaining travelling devices. A first gearbox is arranged between the fixed displacement hydraulic motor and its associated travelling device. One each second gearbox is arranged between each of the hydraulic variable displacement motors and their associated travelling devices. The transmission ratio of the first gearbox is lower than the transmission ratios of the second gearboxes and/or the displacement volume of the fixed displacement motor is smaller than the maximum displacement volume of the variable displacement motors.

A transmission arrangement for a hybrid drive of a motor vehicle, in particular a utility vehicle, having change-speed transmission (G) with a drive output shaft (AW), a retarder (RE) with a retarder shaft (RW), an electric machine (EM) with a rotor shaft (RO) and a first gear ratio step (Ü1) between the drive output shaft (AW) and the retarder shaft (RW). The retarder (RE) is driven by way of the first gear ratio step (Ü1). The electric machine (EM) is arranged with its axis parallel to the retarder (RE) and can be coupled to the retarder shaft (RW) by way of a second gear ratio step (Ü2).

A power transmission device includes a first shaft provided to be rotatable around a first rotational axis of the hydraulic pump driven by the engine. A second shaft is rotatable about the first rotational axis to rotate the power take shaft. A clutch is rotatable about a second rotational axis that is substantially parallel to the first rotational axis and is vertically below the first rotational axis. The clutch has a first rotating portion and a second rotating portion arranged to face each other in the second rotational axis. A first rotating portion is connectable to and separable from the second rotating portion. The first rotation transmission mechanism is configured to transmit rotation of the first shaft to the first rotating portion. A second rotation transmission mechanism is configured to transmit rotation of the second rotating portion to the second shaft.

A power transmission device includes a first shaft provided to be rotatable around a first rotational axis of the hydraulic pump driven by the engine. A second shaft is rotatable about the first rotational axis to rotate the power take shaft. A clutch is rotatable about a second rotational axis that is substantially parallel to the first rotational axis and is vertically below the first rotational axis. The clutch has a first rotating portion and a second rotating portion arranged to face each other in the second rotational axis. A first rotating portion is connectable to and separable from the second rotating portion. The first rotation transmission mechanism is configured to transmit rotation of the first shaft to the first rotating portion. A second rotation transmission mechanism is configured to transmit rotation of the second rotating portion to the second shaft.

Ball screw rotary actuator with ball cage. In one embodiment, a ball screw rotary actuator includes an outer cylinder, a piston, and inner shaft. Outer ball bearings travel in helical groove between the outer cylinder and position to rotate the piston as it translates due to fluid pressure. The inner shaft is situated radially inward of the piston, and straight grooves are disposed between the piston and the inner shaft. Inner ball bearings travel in the straight grooves and rotate the inner shaft as the piston rotates. The ball screw rotary actuator also includes an outer ball cage to position the outer ball bearings in a spaced configuration, an outer indexing gear to control a position of the outer ball cage, an inner ball cage to position the inner ball bearings in a spaced configuration, and an inner indexing gear to control a position of the inner ball cage.

Ball screw rotary actuator with ball cage. In one embodiment, a ball screw rotary actuator includes an outer cylinder, a piston, and inner shaft. Outer ball bearings travel in helical groove between the outer cylinder and position to rotate the piston as it translates due to fluid pressure. The inner shaft is situated radially inward of the piston, and straight grooves are disposed between the piston and the inner shaft. Inner ball bearings travel in the straight grooves and rotate the inner shaft as the piston rotates. The ball screw rotary actuator also includes an outer ball cage to position the outer ball bearings in a spaced configuration, an outer indexing gear to control a position of the outer ball cage, an inner ball cage to position the inner ball bearings in a spaced configuration, and an inner indexing gear to control a position of the inner ball cage.

There is provided a work vehicle including an oil outlet port and a partition part. The oil outlet port opens to a bottom portion in one end side of a transmission case in a vehicle body front-back direction and a vehicle body left-right direction. The oil outlet port takes out a lubricating oil from an interior of the transmission case. The partition part divided an internal space of the transmission case into a first space zone along a sidewall portion of the transmission case, and a second space zone other than the first space zone. The partition part brings the first space zone into a sealed state.

There is provided a work vehicle including a partition wall to keep partition between a first space zone as part of an internal space of the transmission case in which a differential mechanism is located and a second space zone as part of the internal space which is adjacent to the first space zone. An upper space is disposed above the partition wall and configured to allow lubricating oil scooped up from the first space zone by a ring gear to flow in the second space zone. A flow-out path is disposed below the upper space and configured to allow the lubricating oil to flow out of the second space zone to the first space zone.