A mechanical locking differential primarily includes a drive ring and right and left driven rings that can move sideways into and out of engagement with the drive ring. The drive ring and the driven rings have teeth with an inverted trapezoidal shape with a significant clearance, such as a pressure angle of −1° and a clearance of 20% circumferentially. A central ramping separator ring provides a ramping mechanism with inclines that push the driven rings out of engagement with the drive ring when the associated half axle rotates faster than the drive ring, with the ramping action occurring within the teeth clearance.

A continuously variable speed transmission and steering differential having a central drive axle, two pairs of sheaves and two shift arms. The drive axel is driven by an external power source. The two pairs of sheaves, left and right, are mounted to the drive axel. Each pair of sheaves includes a fixed drive sheave and a movable drive sheave. Each movable drive sheave is positioned by a shift arm. Shifting the shift arms left or right varies the gear ratio between the left and right pair of sheaves thereby providing steering control. Narrowing the distance between the shaft arms increases the gear ratio and consequently puts the transmission into a higher gear, thereby providing speed control.

A drive apparatus includes a motor; a reduction gear connected to the motor; a differential connected to the reduction gear, for rotating an axle about a differential axis; a housing including a gear housing portion housing the reduction gear and the differential; and an oil housed in the gear housing portion. The differential includes a gear for rotating about the differential axis. An end portion of the gear is lower than the reduction gear, and is configured to soak in the oil. The housing includes an oil drain hole and an oil feed hole for joining an interior of the housing and a space outside of the housing, a first stopper member removably in the oil drain hole, and a second stopper member removably in the oil feed hole. Each of the oil drain hole and the oil feed hole is in a portion of the gear housing portion.

A drive apparatus includes a motor; a reduction gear connected to the motor; a differential connected to the reduction gear, for rotating an axle about a differential axis; a housing including a gear housing portion housing the reduction gear and the differential; and an oil housed in the gear housing portion. The differential includes a gear for rotating about the differential axis. An end portion of the gear is lower than the reduction gear, and is configured to soak in the oil. The housing includes an oil drain hole and an oil feed hole for joining an interior of the housing and a space outside of the housing, a first stopper member removably in the oil drain hole, and a second stopper member removably in the oil feed hole. Each of the oil drain hole and the oil feed hole is in a portion of the gear housing portion.

A transmission for a walk-behind wheeled vehicle, the transmission being of the type including at least one casing (2) housing a driver member (3), equipped with rotary drive motor means (4), a rotary driven member (5), two wheel drive shafts (6A, 6B) in alignment, two clutch mechanisms (8) each of which is disposed between the driven member (5) and a wheel drive shaft (6A; 6B), each clutch mechanism (8) being activated by the driven member (5) being driven in rotation forwards, and deactivatable by the wheel drive shaft (6A; 6B) with which it co-operates being driven in rotation forwards, when the speed of rotation of the wheel drive shaft (6A, 6B) is greater than the speed of rotation of the driven member (5). The rotary drive motor means (4) for driving the driver member (3) in rotation are motor means that can be controlled to rotate in two directions of rotation, and each clutch mechanism (8) is of the type that is deactivatable merely by the driven member (5) being driven in rotation in the backwards direction.

A drivetrain system includes a first drive gear driven by a first motor and a second drive gear driven by a second motor. The first drive gear and the second drive gear are arranged along the axis. The first drive gear includes a first extension and the second drive gear includes a second extension arranged radially within and axially overlapping the first extension. The drivetrain system includes a system of bearings arranged between the first drive gear and the second drive gear, either drive gear and a stationary component, or a combination thereof. In some embodiments, the drivetrain system includes a clutch assembly arranged between the first drive gear and the second drive gear that interfaces to the first drive gear and to the second drive gear. The clutch assembly allows the drive gears to be locked or otherwise engaged to improve torque transfer.

A drivetrain system includes a first drive gear driven by a first motor and a second drive gear driven by a second motor. The first drive gear and the second drive gear are arranged along the axis. The first drive gear includes a first extension and the second drive gear includes a second extension arranged radially within and axially overlapping the first extension. The drivetrain system includes a system of bearings arranged between the first drive gear and the second drive gear, either drive gear and a stationary component, or a combination thereof. In some embodiments, the drivetrain system includes a clutch assembly arranged between the first drive gear and the second drive gear that interfaces to the first drive gear and to the second drive gear. The clutch assembly allows the drive gears to be locked or otherwise engaged to improve torque transfer.

A differential gear includes a holder which is provided between first and second pinion gears in a differential case and through which a differential pinion shaft is inserted. An insertion hole is radially formed in the differential pinion shaft. The holder is formed with a fixing hole facing the insertion hole when the differential pinion shaft is inserted through the holder. Due to insertion of a fixing pin through the fixing hole and the insertion hole, the differential pinion shaft and the holder are relatively non-rotatable. Due to the holder being held between first and second side gears, relative rotation of the holder with respect to the differential case is restricted, and the differential pinion shaft is non-rotatable relative to the differential case.

A differential gear includes a holder which is provided between first and second pinion gears in a differential case and through which a differential pinion shaft is inserted. An insertion hole is radially formed in the differential pinion shaft. The holder is formed with a fixing hole facing the insertion hole when the differential pinion shaft is inserted through the holder. Due to insertion of a fixing pin through the fixing hole and the insertion hole, the differential pinion shaft and the holder are relatively non-rotatable. Due to the holder being held between first and second side gears, relative rotation of the holder with respect to the differential case is restricted, and the differential pinion shaft is non-rotatable relative to the differential case.

A drive apparatus includes a motor; a reduction gear connected to the motor; a differential connected to the reduction gear, for rotating an axle about a differential axis; a housing including a gear housing portion housing the reduction gear and the differential; and an oil housed in the gear housing portion. The differential includes a gear for rotating about the differential axis. An end portion of the gear is lower than the reduction gear, and is configured to soak in the oil. The housing includes an oil drain hole and an oil feed hole for joining an interior of the housing and a space outside of the housing, a first stopper member removably in the oil drain hole, and a second stopper member removably in the oil feed hole. Each of the oil drain hole and the oil feed hole is in a portion of the gear housing portion.