A power transmission apparatus includes a first input shaft receiving an input torque, second and third input shafts coaxially disposed and selectively connected with the first input shaft, first and second torque mediating shafts coaxially disposed with the first input shaft, first and second intermediate shafts and an output shaft disposed in parallel with the first input shaft, a first shifting section receiving a torque from the third input shaft and outputting a plurality of first shifted torques, a second shifting section including a first planetary gear set selectively connected with the first input shaft and outputting a plurality of second shifted torques, and a compound shifting section forming an output torque by the input torque and the first and second shifted torques.

A power transmission apparatus includes: a first input shaft always receiving an input torque from an engine; second and third input shafts coaxially disposed and selectively connected with the first input shaft; a torque mediating shaft selectively connected with the first input shaft or a transmission housing; first and second intermediate shafts and an output shaft respectively disposed in parallel with the first input shaft; a first preliminary shifting section receiving a torque through a first input gear set, selectively shifting the received torque, and outputting the shifted torque; a second preliminary shifting section including a second shifting gear set which outputs a torque from the first input shaft and stops ;and a compound shifting section forming an output torque by the input torque and the first and second shifted torques.

A transmission for a vehicle includes an input shaft, a planetary gearset comprising a sun gearwheel, one or more planet gearwheels, a planet gearwheel holder and a planet ring gearwheel, a first gearwheel, a second gearwheel, a third gearwheel, a fourth gearwheel and a fifth gearwheel, an output shaft, and at least two gear engaging devices which are configured to provide at least four selectable gear connections. The planet ring gearwheel is rotatably connected or connectable to the first gearwheel. A first gear engaging device is configured to be provided in a first state where it rotationally connects the second gearwheel to the fourth gearwheel and in a second state where it rotationally disconnects the second gearwheel from the fourth gearwheel. The third selectable gear connection is provided by at least setting the first gear engaging device in the first gear engaging device first state.

Methods and systems are provided for a transmission. In one example, a system includes a shifting mechanism arranged between a first planetary gearset and a second planetary gearset arranged in series, wherein the shifting mechanism is configured to adjust an operating mode to a first mode, a second mode, or a tow mode.

A power-split hybrid transmission includes a direction reversing mechanism between the transmission input and a power-splitting planetary gear set. The transmission input is driven by an internal combustion engine. Engaging the direction reversing mechanism to drive the carrier in a direction opposite of engine rotation permits the transaxle to achieve higher output torque in reverse when using predominantly engine power. The direction reversing mechanism may also be used to hold the carrier stationary, providing a torque reaction to propel the vehicle with a generator, thus increasing the output torque in both directions when operating under only battery power.

A geared transmission unit in which flexibility in arrangements of shafts and members coupled to the shafts is enhanced. The geared transmission unit comprises: a pair of pinion gears having different teeth numbers that rotate integrally; a carrier that rotates while supporting the pinion gears in a rotatable manner; a fixed gear meshed with a first pinion gear; a first transmission gear arranged on an inner circumferential side of the carrier while being meshed with a second pinion gear; an external gear formed on an outer circumferential face of the carrier; and second transmission gears respectively meshing with the external gear.

A multi-stage transmission bicycle, comprises: a transmission plate which rotates with the pedals and has a plurality of transmission gear teeth formed concentrically on the surface and driving gear teeth on the outer peripheral side; a transmission unit having an input shaft, which is coupled to the driving teeth and is for receiving transmission of the rotational force, a ring gear, which rotates by means of the input shaft, an output shaft, which is disposed inside the ring gear, has a sun gear, and is coupled to the rear wheel, pinion gears, which are coupled to the sun gear and inner gear teeth of the ring gear, a carrier, which couples the pinion gears, and a driving gear which is gear coupled to the carrier; and a number-of-revolutions changing module for changing the rotational direction of the driving gear and the number of revolutions of the driving gear.

A power transmission apparatus includes: a first input shaft; a second input shaft coaxially disposed with the first input shaft and selectively connected with the first input shaft; a third input shaft coaxially disposed with the second input shaft and selectively connected with the first input shaft; a first output shaft in parallel with the first input shaft; a second output shaft arranged in series to and selectively connected with the first output shaft; a first shift-stage shifting section outputting two shifted torques from the third input shaft to the first output shaft; a second shift-stage shifting section outputting one shifted torque and one reverse torque from the second input shaft to the first output shaft; and a compound shifting section outputting a shifted output torque from a received torque selectively from the first input shaft or the first output shaft.

A power transmission apparatus for a vehicle includes a first input shaft selectively connected with an engine output shaft through a first clutch; a second input shaft selectively connected to the engine output shaft through a second clutch; a third input shaft selectively connected to the engine output shaft through a third clutch; a power transmission shaft disposed about the external circumference of the second input shaft; first and second center shafts selectively connected with each other through a fourth clutch; an idle shaft disposed in parallel with the first input shaft; a fixed transmission for selectively shifting torque input to various shafts and outputting the torque through the second center shaft and the power transmission shaft; a composite transmission configured to complementarily composite shift and output input torque; and an output shaft outputting the torque transmitted from the composite transmission to a final reduction gear.

A power transmission apparatus for a vehicle is disclosed. The power transmission apparatus includes three concentric input shafts, input shaft fixedly connected to an engine output shaft, a transmitting shaft disposed on the outer circumference of the first input shaft without rotation interference, a central shaft parallel to a first one of the input shafts and spaced apart from the first input shaft by a predetermined interval, a fixed transmission selectively shifting an input torque depending on the respective gear ratios of four change gear trains disposed between first and second input shafts, the transmitting shaft, and the central shaft and each having drive gears and driven gears externally connected to each other and outputting the shifted torque through the central shaft and the transmitting shaft, and composite transmission including a planetary gear set having a sun gear fixedly connected to one side of the transmitting shaft.