A dog clutch includes a gear (40) mounted on a power transmission shaft (30), first and second dog rings (10, 20), a fork (60), springs (65), and cam grooves (31). The cam grooves (31) each include a first slope surface (36) inclined from the axial direction toward the positive rotation direction as the first slope surface (36) approaches the gear (40) and a second parallel surface (37) parallel to the axial direction. The first dog ring (10) includes first cam protrusions (16) to be engaged with the respective first slope surfaces (36), and the second dog ring (20) includes second cam protrusions (26) to be engaged with the respective second parallel surfaces (37). This structure prevents the dog rings and the fork from coming into contact with each other, thereby avoiding generation of abrasion and increasing the transmission efficiency.

A clutch arrangement having a first coupler mounted for rotation with a first input gear, a second coupler mounted for rotation with a second input gear, and an input-gear selector mounted for rotation with an input shaft and positioned between the first and second couplers. The input-gear selector is movable on the input shaft relative to the first and second couplers. Engagement of the input-gear selector with the first coupler drives rotation of the first input gear with rotation of the input shaft, and engagement of the input-gear selector with the second coupler drives rotation of the second input gear with rotation of the input shaft.

A vehicle transmission has a plurality of gear positions that are to be selectively established, and includes: an input shaft; a first shaft; a second shaft; an output shaft; at least one first drive gear disposed on the first shaft; at least one second drive gear disposed on the second shaft; at least one driven gear disposed on the output shaft; a dog clutch connecting and disconnecting between the input shaft and each of the first and second shafts; and a synchronous meshing apparatus. The synchronous meshing apparatus connects and disconnects between each of the first and second shafts and the output shaft, and, when connecting between each of the first and second shafts and the output shaft, establishes a power transmission path from each of the first and second shafts to the output shaft via a selected one of the at least one first or second drive gear.

A vehicle transmission has a plurality of gear positions that are to be selectively established, and includes: an input shaft; a first shaft; a second shaft; an output shaft; at least one first drive gear disposed on the first shaft; at least one second drive gear disposed on the second shaft; at least one driven gear disposed on the output shaft; a dog clutch connecting and disconnecting between the input shaft and each of the first and second shafts; and a synchronous meshing apparatus. The synchronous meshing apparatus connects and disconnects between each of the first and second shafts and the output shaft, and, when connecting between each of the first and second shafts and the output shaft, establishes a power transmission path from each of the first and second shafts to the output shaft via a selected one of the at least one first or second drive gear.

A first dog ring and a second dog ring are biased toward each other by means of springs. When the first dog ring and the second dog ring are moved away from each other, bias force produced by the springs is applied to the second dog ring in a direction to draw the second dog ring toward the first dog ring. Accordingly, when the first dog ring is moved away from the second dog ring during shifting, the second dog ring is drawn toward the first dog ring under the bias force, and third engaging teeth of the second dog ring and meshing teeth of a first-speed gear are promptly disengaged from each other.

A first dog ring and a second dog ring are biased toward each other by means of springs. When the first dog ring and the second dog ring are moved away from each other, bias force produced by the springs is applied to the second dog ring in a direction to draw the second dog ring toward the first dog ring. Accordingly, when the first dog ring is moved away from the second dog ring during shifting, the second dog ring is drawn toward the first dog ring under the bias force, and third engaging teeth of the second dog ring and meshing teeth of a first-speed gear are promptly disengaged from each other.

Drive systems or powertrains including transmissions for electric and hybrid electric vehicles are provided. 3-position linear motor, 2-way clutches (i.e. CMDs) are included in the transmissions. An electric 3-speed AMT having a magnetic coupling device such as a magnetic torque converter is provided to magnetically transfer a portion of rotating mechanical energy of an electric powerplant or motor to a transmission output shaft in response to an electrical signal to synchronize angular velocities of the transmission output shaft and an output shaft of the electric powerplant during a change in state of one of the CMDs. Torque is transferred to the transmission output shaft during the change in state.

Drive systems or powertrains including transmissions for electric and hybrid electric vehicles are provided. 3-position linear motor, 2-way clutches (i.e. CMDs) are included in the transmissions. An electric 3-speed AMT having a magnetic coupling device such as a magnetic torque converter is provided to magnetically transfer a portion of rotating mechanical energy of an electric powerplant or motor to a transmission output shaft in response to an electrical signal to synchronize angular velocities of the transmission output shaft and an output shaft of the electric powerplant during a change in state of one of the CMDs. Torque is transferred to the transmission output shaft during the change in state.

A dog clutch for a vehicle includes gear-side meshing teeth provided on a shifting gear fitted so as to be rotatable relative to a shaft, and a dog ring disposed adjacent to the shifting gear in the axial direction of the shaft. The dog ring includes a first ring, a second ring, and springs interposed between the two rings. The first ring is provided with meshing teeth that can be meshed with the gear-side meshing teeth of the shifting gear. The second ring is provided with meshing teeth that can be meshed with the gear-side meshing teeth of the shifting gear. The springs are provided on the inner peripheral side of a circle that is centered on a rotational axis and that circumscribes a portion of the meshing teeth of the first ring and the second ring positioned on the outermost peripheral side.

A gear unit for a motor vehicle with a main input shaft and an auxiliary input shaft which is connected thereto via a constant gearwheel set step, wherein the constant gearwheel set step can further be connected to the output via a reverse gearwheel set step. At least one synchronized shifting clutch for connecting at least one idler gearwheel of the reverse gearwheel set step to the shaft carrying the idler gearwheel such that the idler gearwheel is fixed with respect to rotation relative to the shaft. The invention is further directed to a motor vehicle including such gear unit.