Systems and methods for controlling transmissions having CVTs are disclosed with multiple modes and gearing arrangements for range enhancements, where embodiments include synchronous shifting to allow the transmission to achieve a continuous range of transmission ratios, while minimizing “empty” cycling of the CVT during mode shifts. Embodiments provide for wide ratio range and performance and efficiency flexibility, while maximizing CVT usage through synchronous shifting.

A work vehicle including: a transmission unit that is provided with, on a shaft that is provided in a power transmission path leading from an input shaft to a power transmission shaft but is not a speed change shaft, a gear member that has an engagement recess, and a claw member having an engaging claw that engages with the engagement recess and to which rotational power is transmitted. There are gaps in a rotational direction between the engaging claw and both ends, in the rotational direction, of the engagement recess.

Systems and methods for operating a driveline system are disclosed and include a step-variable transmission. A continuously variable transmission (CVT) is coupled between an input source and the step-variable transmission. The CVT receives a first torque from the input source and outputs a second torque. The CVT has a plurality of planetary members in rolling contact with an inner race and an outer race. A radial distance between the planetary members and a drive-transmitting member corresponds to a transmission ratio of the CVT.

A gear-double ring-hydraulic hybrid transmission device includes an input mechanism, a double ring series transmission mechanism, a hydraulic transmission mechanism, an output member, a front planetary gear mechanism, a middle planetary gear mechanism, a rear planetary gear mechanism, a clutch assembly, and a brake assembly. An output of the double ring series transmission mechanism is connected to the middle planetary gear mechanism. The clutch assembly connects the input mechanism to the double ring series transmission mechanism, the hydraulic transmission mechanism, and the front planetary gear mechanism, connects an output of the hydraulic transmission mechanism to the middle planetary gear mechanism, and connects an output of the rear planetary gear mechanism to the output member. The clutch assembly and the brake assembly provide a continuous transmission ratio between the input mechanism and the output member.

A transmission includes a first shaft with two gears adapted for connecting to a motor and a second shaft with two corresponding gears adapted for connecting to a driveshaft; a shift drum selectively controlling torque transfer between the shafts and defining therein two grooves; a shift rod translatable along a rod axis with a driving member fixedly connected thereto and engaging one groove, at least a portion of the groove causing the driving member and the shift rod to translate along the rod axis upon rotation of the shift drum; an engagement dog disposed on the second shaft for selectively engaging the gears of the second shaft; two biasing members disposed around the shift rod; a fork rod supporting a shift fork slidably connected to the fork rod and the shift rod, the shift fork being engaged in another groove of the shift drum.

A snowmobile has a gearbox having a first shaft, a second shaft, first transmission gears mounted to the first shaft and second transmission gears mounted to the second shaft. A driven gear mounted to the first shaft engages a forward drive gear mounted to a countershaft. In a first configuration: the first shaft is coupled to the countershaft; when rotating, a driveshaft rotates in a same direction as the countershaft; and configurable portions of the countershaft and second shaft are free of gears. In a second configuration: the forward drive gear is in selective free-spin engagement with the countershaft; a reverse drive gear mounted to the configurable portion of the countershaft is in driving engagement with the countershaft; an actuator selectively transmits rotary motion from the countershaft to the gearbox; a reverse driven gear mounted to the configurable portion of the second shaft meshes with the reverse drive gear.

Systems and methods for controlling transmissions having CVTs are disclosed with multiple modes and gearing arrangements for range enhancements, where embodiments include synchronous shifting to allow the transmission to achieve a continuous range of transmission ratios, while minimizing “empty” cycling of the CVT during mode shifts. Embodiments provide for wide ratio range and performance and efficiency flexibility, while maximizing CVT usage through synchronous shifting.

This invention provides a continuously variable transmission (CVT) system using variable disk friction drive. The CVT system comprises a variator (17) including a roller (216), having a cam follower (243; 247), which is radially displaceable from a central axis and mounted in friction drive contact with a drive disk (15); and a rotatable spiral cam (181 ) including a spiral cam cavity (301) arranged such that the roller (216) and the cam follower (243; 247) protrudes through the spiral cam cavity (301), the spiral cam (181) being rotatable about a central axis to radially displace the roller (216). The invention includes a three-mode synchronous system adapted to cooperate with the variator (17).

Systems and methods for controlling transmissions having CVTs are disclosed with multiple modes and gearing arrangements for range enhancements, where embodiments include synchronous shifting to allow the transmission to achieve a continuous range of transmission ratios, while minimizing “empty” cycling of the CVT during mode shifts. Embodiments provide for wide ratio range and performance and efficiency flexibility, while maximizing CVT usage through synchronous shifting.

A gear-double ring-hydraulic hybrid transmission device includes an input mechanism, a double ring series transmission mechanism, a hydraulic transmission mechanism, an output member, a front planetary gear mechanism, a middle planetary gear mechanism, a rear planetary gear mechanism, a clutch assembly, and a brake assembly. An output of the double ring series transmission mechanism is connected to the middle planetary gear mechanism. The clutch assembly connects the input mechanism to the double ring series transmission mechanism, the hydraulic transmission mechanism, and the front planetary gear mechanism, connects an output of the hydraulic transmission mechanism to the middle planetary gear mechanism, and connects an output of the rear planetary gear mechanism to the output member. The clutch assembly and the brake assembly provide a continuous transmission ratio between the input mechanism and the output member.