A system and method for compensating reduced track speed because of engine droop for a work machine is disclosed. The system may comprise a frame, an attachment coupled to the frame, a ground-engaging mechanism adapted to support the frame, an engine, a motor, a track speed sensor, an engine speed sensor, and a controller. The engine may drive the ground-engaging mechanism and attachment. The engine may be coupled through a variable speed transmission to the ground-engaging mechanism and the attachment. They variable speed transmission may include a hydrostatic circuit. The controller may be adapted to send an increased transmission command signal based on a drop in the engine speed signal when the work machine engages an increased load. The increased transmission command signal may increase a motor speed to cause an increase in track speed to compensate at least a portion of the reduced track speed from the engine speed droop.

A hydraulic motor for vehicle wheel includes a hydrodynamic element, a reaction element, an oil distributor rotating as one with the reaction element, and a brake mounted between the two elements to oppose the rotational movement. The hydrodynamic element has a flange that surrounds the oil distributor. On its radially exterior face, it has means for rotationally coupling with the rotary discs of the brake. The brake is thus positioned around the distributor.

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 vehicle drive assistance system equipped with an open hydraulic circuit has a hydraulic pump, a hydraulic motor and a reservoir. The system has a three-position valve suitable for: in a first position, supplying the hydraulic motor in a first direction of operation; in a second position, fluidly isolating the hydraulic motor from the hydraulic pump and connecting the hydraulic motor to the reservoir; and in a third position, supplying the hydraulic motor in a second direction of operation. A flow controller is positioned between the hydraulic pump and the three-position valve. The flow controller is configured in such a way as to selectively allow or not allow the passage of fluid through the supply duct of the hydraulic pump toward the three-position valve.

A vehicle drive assistance system equipped with an open hydraulic circuit has a hydraulic pump, a hydraulic motor and a reservoir. The system has a three-position valve suitable for: in a first position, supplying the hydraulic motor in a first direction of operation; in a second position, fluidly isolating the hydraulic motor from the hydraulic pump and connecting the hydraulic motor to the reservoir; and in a third position, supplying the hydraulic motor in a second direction of operation. A flow controller is positioned between the hydraulic pump and the three-position valve. The flow controller is configured in such a way as to selectively allow or not allow the passage of fluid through the supply duct of the hydraulic pump toward the three-position valve.

A multipurpose vehicle includes an engine, a travel transmission device, a continuously variable transmission device, and a spacer housing capable of becoming attached to and detached from the engine, the continuously variable transmission device, and the travel transmission device. The spacer housing contains an engine output shaft, a transmission device input shaft of the continuously variable transmission device, a first connecting portion connecting the engine output shaft with the transmission device input shaft in an interlocking manner, a transmission device output shaft of the continuously variable transmission device, a transmission input shaft of the travel transmission device, and a second connecting portion connecting the transmission device output shaft with the transmission input shaft in an interlocking manner.

A multipurpose vehicle includes an engine, a travel transmission device, a continuously variable transmission device, and a spacer housing capable of becoming attached to and detached from the engine, the continuously variable transmission device, and the travel transmission device. The spacer housing contains an engine output shaft, a transmission device input shaft of the continuously variable transmission device, a first connecting portion connecting the engine output shaft with the transmission device input shaft in an interlocking manner, a transmission device output shaft of the continuously variable transmission device, a transmission input shaft of the travel transmission device, and a second connecting portion connecting the transmission device output shaft with the transmission input shaft in an interlocking manner.

A power transmission device includes a torque converter device, a first hydraulic pump, a first oil channel, a second oil channel, a third oil channel, a second pressure control valve, and a controller. The torque converter device has a torque converter and a lock-up clutch. The first oil channel supplies hydraulic fluid from the first hydraulic pump to the torque converter. The second oil channel drains hydraulic fluid from the torque converter. The third oil channel communicates with the first oil channel and the second oil channel. The second pressure control valve is disposed in the third oil channel. The controller sets the second pressure control valve to an open state when the lock-up clutch is in an engaged state.

A power transmission device includes a torque converter device, a first hydraulic pump, a first oil channel, a second oil channel, a third oil channel, a second pressure control valve, and a controller. The torque converter device has a torque converter and a lock-up clutch. The first oil channel supplies hydraulic fluid from the first hydraulic pump to the torque converter. The second oil channel drains hydraulic fluid from the torque converter. The third oil channel communicates with the first oil channel and the second oil channel. The second pressure control valve is disposed in the third oil channel. The controller sets the second pressure control valve to an open state when the lock-up clutch is in an engaged state.