F16H61/439

WORK VEHICLE
20210254710 · 2021-08-19 ·

A work vehicle such as a tractor including an engine, a battery, a hydraulic continuously variable transmission, and an electric cylinder, and a power transmission mechanism. The hydraulic continuously variable transmission changes an output of the engine, and changes an angle of a movable swash plate to change a gear ratio thereof. The electric cylinder is driven by electric power supplied from the battery at least while the engine is stopped. With the power generated in the electric cylinder and transmitted, the power transmission mechanism changes the angle of the movable swash plate of the hydraulic continuously variable transmission.

Traveling hydraulic stepless transmission

A traveling hydraulic stepless transmission (“HST”), ensures stopping of a vehicle on a slope under high load conditions, maintains stopping the vehicle on flat ground under low load conditions, and enables smooth starting from a stop. The HST includes a neutral check valve (“NCV”) and an internal damping system (“IDS”). The NCV includes a first orifice that opens a first oil passage to a transaxle case when a pressure in the first oil passage is equal to or less than a predetermined pressure, and that connects the second oil passage to the transaxle case when a pressure in a second oil passage is equal to or less than the predetermined pressure. The IDS includes second orifices that connect a high pressure side of the oil passages to the transaxle case when a discharge rate of the hydraulic pump is equal to or less than a predetermined discharge rate.

Traveling hydraulic stepless transmission

A traveling hydraulic stepless transmission (“HST”), ensures stopping of a vehicle on a slope under high load conditions, maintains stopping the vehicle on flat ground under low load conditions, and enables smooth starting from a stop. The HST includes a neutral check valve (“NCV”) and an internal damping system (“IDS”). The NCV includes a first orifice that opens a first oil passage to a transaxle case when a pressure in the first oil passage is equal to or less than a predetermined pressure, and that connects the second oil passage to the transaxle case when a pressure in a second oil passage is equal to or less than the predetermined pressure. The IDS includes second orifices that connect a high pressure side of the oil passages to the transaxle case when a discharge rate of the hydraulic pump is equal to or less than a predetermined discharge rate.

Work vehicle

A work vehicle such as a tractor including an engine, a battery, a hydraulic continuously variable transmission, and an electric cylinder, and a power transmission mechanism. The hydraulic continuously variable transmission changes an output of the engine, and changes an angle of a movable swash plate to change a gear ratio thereof. The electric cylinder is driven by electric power supplied from the battery at least while the engine is stopped. With the power generated in the electric cylinder and transmitted, the power transmission mechanism changes the angle of the movable swash plate of the hydraulic continuously variable transmission.

Work vehicle

A work vehicle such as a tractor including an engine, a battery, a hydraulic continuously variable transmission, and an electric cylinder, and a power transmission mechanism. The hydraulic continuously variable transmission changes an output of the engine, and changes an angle of a movable swash plate to change a gear ratio thereof. The electric cylinder is driven by electric power supplied from the battery at least while the engine is stopped. With the power generated in the electric cylinder and transmitted, the power transmission mechanism changes the angle of the movable swash plate of the hydraulic continuously variable transmission.

Control assembly for zero turn device
10974763 · 2021-04-13 · ·

A control assembly for use with a vehicle having a pivot arm for controlling output of the vehicle includes a bracket, a yoke attached to the pivot arm, and a shaft engaged to the yoke and extending into the bracket. The pivot arm is rotatable about a first axis of rotation between a neutral position and a plurality of forward positions and a plurality of reverse positions. When in the neutral position, the pivot arm may also rotate about a second axis of rotation between an operative position and a stopped position, and a switch may be engaged when the pivot arm is rotated to the stopped position. A return to neutral assembly may provide a return force to the pivot arm when it is rotated about the first axis of rotation away from the neutral position.

Control assembly for zero turn device
10974763 · 2021-04-13 · ·

A control assembly for use with a vehicle having a pivot arm for controlling output of the vehicle includes a bracket, a yoke attached to the pivot arm, and a shaft engaged to the yoke and extending into the bracket. The pivot arm is rotatable about a first axis of rotation between a neutral position and a plurality of forward positions and a plurality of reverse positions. When in the neutral position, the pivot arm may also rotate about a second axis of rotation between an operative position and a stopped position, and a switch may be engaged when the pivot arm is rotated to the stopped position. A return to neutral assembly may provide a return force to the pivot arm when it is rotated about the first axis of rotation away from the neutral position.

Neutral valve and valve assembly including same
10774848 · 2020-09-15 · ·

A neutral valve includes a spool inserted in a housing so as to be movable in a predetermined direction, the spool configured to move to a neutral position set such that a first and second port are connected to each other through a valve passage, a first offset position located at neutral position's first side in the predetermined direction and set such that second port and valve passage are disconnected from each other, and a second offset position located at neutral position's second side in the predetermined direction and set such that first port and valve passage are disconnected from each other. The spool's outer peripheral portion includes a first pressure receiving surface receiving first port's fluid pressure to be pushed toward the first side in the predetermined direction and a second pressure receiving surface receiving second port's fluid pressure to be pushed toward second side in the predetermined direction.

Return to neutral mechanism for hydrostatic transmission

A return-to-neutral mechanism for a hydrostatic transmission configured to return a control member of a pump to neutral after the control member has been moved toward a forward or reverse position. The return-to-neutral mechanism includes a stop member mountable to a housing, a control arm for moving the control member, and a spring for engaging the control arm and stop member to bias and return the control arm to neutral after being released from forward or reverse positions. The stop member may have an opening for receiving a fastener for mounting to the housing, and the opening may be configured to permit adjustment of the stop member along at least two transverse directions to preload the spring at the neutral position. The control arm may have abutments for moving legs of the spring, and the abutments may have recessed and protruding portions for receiving and containing the spring legs.

Return to neutral mechanism for hydrostatic transmission

A return-to-neutral mechanism for a hydrostatic transmission configured to return a control member of a pump to neutral after the control member has been moved toward a forward or reverse position. The return-to-neutral mechanism includes a stop member mountable to a housing, a control arm for moving the control member, and a spring for engaging the control arm and stop member to bias and return the control arm to neutral after being released from forward or reverse positions. The stop member may have an opening for receiving a fastener for mounting to the housing, and the opening may be configured to permit adjustment of the stop member along at least two transverse directions to preload the spring at the neutral position. The control arm may have abutments for moving legs of the spring, and the abutments may have recessed and protruding portions for receiving and containing the spring legs.