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 detent mechanism 70 is provided for fixing a shift drum 58 in position at a rotation operation position where shift gears 36, 37 become engageable. The detent mechanism 70 includes a positioning rotation portion 71 formed in the shift drum 58, a positioning arm 72 engageable with a positioning action portion 74 formed in the positioning rotation portion 71 for fixing the shift drum 58 at a rotation position corresponding to a rotation operation position of the shift drum 58, and a positioning spring 73 for urging the positioning arm 72 for its engagement with the positioning action portion 74. The positioning arm 72, as being rotatably supported to a speed changing operation shaft 61 for rotating the shift drum 58, is extended from a speed changing operation shaft 61.

A gear transmission (20) includes a plurality of shift gears (36, 37), a plurality of shifters (55, 56) engaged, respectively, with the plurality of shift gears (36, 37), and a shift drum (58) rotatably operated by a stepped speed changing operational tool (66) to operate the plurality of shifters (55, 56), thus being speed-changed in forward three speed stages. The stepped speed changing operational tool (66) is switched to a neutral position, a forward third speed position, a forward second speed position and a forward first speed position in this cited order.

A gear transmission having a speed changing section includes a speed changing gear for setting a speed stage and a shift gear slidably mounted on a rotation support shaft and operated to engage and disengage with the speed changing gear, the speed changing section configured to speed-change inputted power and to output the resultant power via the rotation support shaft. An arrangement is provided for facilitating engagement of the shift gear with the speed changing gear even when respective end faces of the shift gear and the speed changing gear hit each other. A transmission mechanism (20B) is provided for outputting power of a rotation support shaft (24) to a traveling device. The transmission mechanism (20B) has a transmission flexibility portion (80) which allows free rotation of the rotation support shaft (24) by a set rotation angle.

A structure of a speed sensor arrangement of a vehicle is provided. The vehicle includes a power unit. The power unit is connected with a transmission system. The transmission system is formed with a sensing space. The sensing space is provided therein with a speed sensor. As such, the speed sensor is arranged in a completely concealed space to prevent the speed sensor from being hit by external sand and stones or corroded by external dust or moisture.

A gear transmission (20) includes a plurality of shift gears (36, 37), a plurality of shifters (55, 56) engaged, respectively, with the plurality of shift gears (36, 37), and a shift drum (58) rotatably operated by a stepped speed changing operational tool (66) to operate the plurality of shifters (55, 56), thus being speed-changed in forward three speed stages. The stepped speed changing operational tool (66) is switched to a neutral position, a forward third speed position, a forward second speed position and a forward first speed position in this cited order.

A gearbox for a vehicle includes: a housing; first and second shafts extending parallel to one another; first transmission gears mounted to the first shaft; and second transmission gears mounted to the second shaft. The transmission gears are helical gears. The first transmission gears are in constant mesh with the second transmission gears to form a plurality of gear pairings engageable to operate the gearbox in different gears. A drive gear is mounted to an input shaft extending into the housing. The input shaft is operatively connected to an engine of the vehicle. A driven gear is mounted to the second shaft and is configured to engage the drive gear. The drive and driven gears are spur gears. A flexible driving member is configured to drivingly connect one of the first shaft and the second shaft to an output shaft. A snowmobile including a gearbox is also contemplated.

A shift control apparatus for a vehicle automatic transmission to be provided in a vehicle that includes a hydraulic transmission device having a lockup clutch, an engine, an input shaft connected to the engine through the hydraulic transmission device, and drive wheels. The shift control apparatus includes a shift-down control portion configured, when a shift-down operation is executed to establish a first gear position by releasing a second engagement device, during running of the vehicle in a driven state with a second gear position being established with engagement of the second engagement device, to increase a torque of the engine so as to increase an input rotational speed as a rotational speed of the input shaft through the lockup clutch that is placed in an engaged state, and to release the lockup clutch before the input rotational speed reaches a synchronous speed of the first gear position.

A power transmission system of a vehicle may include: a first input shaft selectively connectable to an engine output through a first clutch; a second input shaft selectively connectable to the engine output through a second clutch; a first intermediate shaft; a second intermediate shaft; an output shaft disposed in parallel with and apart from the first intermediate shaft and transmitting power from the first intermediate shaft and the second intermediate shaft to a final reduction gear of a differential apparatus; a motor/generator fixedly connected to any one of the first input shaft and the first intermediate shaft; a continuously variable shifting device operably connecting the first input shaft to the first intermediate shaft; and a plurality of shifting gear sets operably connecting the second input shaft, the first and the second intermediate shaft and the output shaft with each other.

The invention relates to a powertrain for a fully electric vehicle comprising an electric machine (1), a driven wheel (2) and a gearing (3) that is arranged between the electric machine (1) and the driven wheel (2) and that provides a driving connection there between, which gearing (3) includes at least a first speed reduction stage (31) providing a fixed first speed ratio, a variator unit (40) providing a variable speed ratio and a second speed reduction stage (32) providing a fixed second speed ratio between an input gear wheel (35) and an output gear wheel (36) thereof, whereof the input gear wheel (35) rotates as one with the output shaft of variator unit (40). According to the invention, a maximum overall speed ratio provided by the gearing (3) between the electric machine (1) and the driven wheel (2) amounts to at least 20:1.