Methods and systems for a hydromechanical transmission. In one example, the transmission system includes a hydrostatic assembly including a variable displacement hydraulic pump and a hydraulic motor and a planetary gearset coupled to a multi-speed gearbox, a hydraulic motor, and an output shaft via separate gears and shafts. In the system the variable displacement hydraulic pump is coupled to an input of the multi-speed gearbox, the multi-speed gearbox includes one or more clutches and is coupled to a prime mover and the output shaft is designed to couple to an axle.

Methods and systems for a hydromechanical transmission are provided herein. In one example, the transmission operating method includes asynchronously shifting between a first pair of drive ranges in the transmission via operation of two clutches and a variable displacement hydraulic pump in a hydrostatic assembly. In the method, asynchronously shifting between the two drive ranges includes a plurality of phases that include a swiveling phase where a speed of the hydrostatic assembly is inverted.

A work vehicle includes a vehicle body provided with a travel device; a prime mover provided in the vehicle body; a transmission device capable of speed-changing a driving force from the prime mover and transmitting the driving force to the travel device; a transmission case housing the transmission device and being filled with lubricating oil; and a control device capable of switching between a warm-up operation mode in which a gear of the transmission device is rotated in a state in which transmission of power from the transmission device to the travel device is blocked and a travel operation mode in which the gear is rotated in a state in which the power is transmitted from the transmission device to the travel device.

A drivetrain for connection between the output of a prime mover and a load is described herein. The drivetrain comprising a CVT including an input connected to the output of the prime mover and an output; a forward-reverse clutch assembly including first and second inputs and an output connectable to the load; the first input of the forward-reverse clutch assembly being connected to the output of the CVT through a CVT clutch. The drivetrain also includes an IVT gear assembly having a first input connected to the output of the prime mover, a second input connected to the output of the CVT and an output connected to the second input of the forward reverse clutch assembly through an IVT clutch; and an idler gear assembly interconnecting the first and second inputs of the forward-reverse clutch assembly.

A work vehicle includes an engine, a speed changing apparatus that includes a hydrostatic stepless speed changing mechanism and is configured to subject motive power transmitted from the engine to speed changing and output the motive power, a travelling apparatus configured to travel on the motive power received from the speed changing apparatus, a speed detector configured to detect a speed of the travelling apparatus, a pressure detector configured to detect a hydraulic pressure in a closed circuit of the hydrostatic stepless speed changing mechanism, and a controller.

A drive-train of an agricultural machine, such as a tractor, has a power-split transmission (1) and a separate transfer case (2). The transfer case (2) can be connected to a drive motor and the gear ratio of the transfer case (2) can be adapted in such manner that the power-split transmission (1) can be used for various drive powers.

The work vehicle includes a vehicle body provided with a travel device; a prime mover provided in the vehicle body; a transmission device capable of speed-changing a driving force from the prime mover and transmitting the driving force to the travel device; a transmission case housing the transmission device and being filled with lubricating oil; and a controller capable of switching between a warm-up operation mode in which a gear of the transmission device is rotated in a state in which transmission of power from the transmission device to the travel device is blocked and a travel operation mode in which the gear is rotated in a state in which the power is transmitted from the transmission device to the travel device.

A gear-hydraulic-metal belt integrated multi-mode hydro-mechanical hybrid transmission device includes an input assembly, an output assembly, a metal belt transmission mechanism, a planetary gear assembly, a hydraulic transmission mechanism, a clutch assembly and a brake assembly. The input assembly is connected to the metal belt transmission mechanism, the planetary gear assembly and the hydraulic transmission mechanism. The metal belt transmission mechanism and the hydraulic transmission mechanism are connected to the planetary gear assembly. The planetary gear assembly is connected to the output assembly. The clutch assembly connects the input assembly to the metal belt transmission mechanism and the planetary gear assembly, and connects each of the metal belt transmission mechanism and the hydraulic transmission mechanism to the planetary gear assembly. The clutch assembly and the brake assembly provide a continuous transmission ratio between the input assembly and the output assembly.

A carrier includes a first carrier portion and a second carrier portion. The first carrier portion includes a gear housing space that houses a planetary gear, an opening that opens the gear housing space toward the second carrier portion and allows the planetary gear to fit into the gear housing space, and a first support hole that supports a first end portion of the planetary support shaft. The second carrier portion includes a cover portion that covers the opening, a second support hole that supports a second end portion of the planetary support shaft, and a joining portion that detachably joins the second carrier portion to the first carrier portion. The joining portion is joined to the first carrier portion by being tightened in a direction aligned with a direction of an axial core of a sun gear.

A work vehicle includes a vehicle body provided with a travel device; a prime mover provided in the vehicle body; a transmission device capable of speed-changing a driving force from the prime mover and transmitting the driving force to the travel device; a transmission case housing the transmission device and being filled with lubricating oil; and a control device capable of switching between a warm-up operation mode in which a gear of the transmission device is rotated in a state in which transmission of power from the transmission device to the travel device is blocked and a travel operation mode in which the gear is rotated in a state in which the power is transmitted from the transmission device to the travel device.