A multi-speed automatic transmission includes a housing, a transmission input shaft, and a plurality of clutches. Different combinations of clutches of the plurality of clutches are engaged to generate different gear ratios corresponding to respective forward speeds of the automatic transmission. The plurality of clutches are positioned within the housing and include a first friction clutch coupled the input shaft and having a first hub, and a second friction clutch having a second clutch hub. The second friction clutch is disposed about the input shaft and radially nested within the first clutch hub such that the second friction clutch is positioned radially between the first clutch hub and the input shaft. The first friction clutch is engaged to generate at least two forward speeds of the transmission and the second friction clutch is engaged to generate seven forward speeds of the transmission including the two forward speeds.

An automatic transmission system includes a housing containing automatic transmission fluid (ATF), a plurality of clutches configured to be engaged to generate gear ratios corresponding to forward speeds of the automatic transmission, wherein one clutch of the plurality of clutches is a friction clutch movable between a disengaged state, an engaged state utilized to create one or more gear ratios of the automatic transmission, and a slippingly engaged state between the disengaged state and the engaged state where the friction clutch is not engaged to create a gear ratio of the automatic transmission, and a controller configured to selectively move the friction clutch to the slippingly engaged state when the friction clutch is not being utilized to generate the one or more gear ratios, such that the friction clutch generates heat from friction to thereby rapidly heat the ATF in the housing and improve operating efficiency of the transmission.

In an automatic transmission, the control part controls the engaging mechanisms and recognizes the rotational speed of a drive source and a stop request for the drive source. The automatic transmission changes the rotational speed of the input member to transmission gear ratios by the planetary gear mechanism and the engaging mechanisms so as to freely output the rotation from the output member. The engaging mechanisms include a switching mechanism switchable between a fixed state and a reverse rotation preventing state in which a normal rotation of a corresponding element among the elements of the planetary gear mechanism is allowed and a reverse rotation thereof is prevented. The control part switches the switching mechanism in a state in which the stop request for the drive source is not recognized and the rotational speed of the drive source is equal to or greater than a predetermined value.

Provided is an automatic transmission with which a switching mechanism thereof is hardly damaged even if the hydraulic pressure supplied to a hydraulic pressure control circuit temporarily changes. A control part ECU of the automatic transmission TM switches the first brake B1 to the reverse rotation preventing state when a signal indicating that the slider is at a position corresponding to the reverse rotation preventing state is received while the control unit ECU recognized that it has switched the first brake B1 to the fixed state.

A transmission variator includes a first pulley rotatably attached to an intermediate member of a geartrain, and a second pulley rotatably attached to an output member that is rotatably coupled to the driveline. The geartrain includes an input member, a planetary gear set, a first clutch, a second clutch and an intermediate member. The second clutch is a low drag clutch. The input member rotatably couples to the prime mover. A controller includes an instruction set that is executable to activate only the first clutch in response to a request to operate the driveline in a forward direction, and activate only the second clutch in response to a request to operate the driveline in a reverse direction.

The present invention provides an automatic transmission capable of properly judging faults of a switching mechanism. A control part ECU of the automatic transmission TM has an actual change gear ratio calculating part 10 and a fault judging part 11. Under a condition that the control part ECU has recognized that the first brake device B1 is switched to a reverse rotation preventing state, if the actual change gear ratio is kept to be an actual change gear ratio prior to a reduce of a rotational speed of a drive source ENG when the rotational speed of the drive source ENG is reduced, then the fault judging part 11 judges that a first brake B1 has a fault.

A motor vehicle group transmission with at least one housing, a main transmission and a range transmission connected downstream from the main transmission. The main transmission comprises at least four planetary gearsets, each of which comprises a sun gear, a carrier, a planetary gearwheel mounted on the carrier and a ring gear, and at least five shifting elements. The range transmission includes at least two planetary gearsets, each of which has a sun gear, a carrier, a planetary gearwheel mounted on the carrier and a ring gear, and at least three shifting elements. The main transmission and the range transmission, together in combination, provide at least thirteen forward gears and at least eight reverse gears.

A spur-gear planetary gearbox with multiple ratios has a spur-gear gearbox with at least one first idler gear arranged concentrically to a spur-gear shaft, and a spur gear connected to this spur-gear shaft, a planetary gear mechanism with a first planetary gear set and a second planetary gear set and a planetary gear shaft rotatable about a planetary gear mechanism axis. One of the planetary gear sets is arranged concentrically to the planetary gear mechanism axis. A first planetary gear and a second planetary gear arranged concentrically to the planetary gear mechanism axis. A gear box and a plurality of speed changing devices are provided, wherein the first idler gear meshes with the first planetary gear, and the spur gear meshes with the second planetary gear. The planetary gearbox is characterized in that a second idler gear is arranged on the spur-gear shaft and can be selectively connected thereto in a torque-transmitting manner. The first idler gear can be selectively connected to the gear box in a torque-transmitting manner, and a third planetary gear is arranged concentrically to the planetary gear train axis and meshes with the second idler gear.

A number of variations may include a product comprising an electrical machine operatively connected to a driveline module comprising a gear train having a fixed gear ratio, a first planetary gear set having multiple gear ratios operatively connected to the gear train, a second planetary gear set having a fixed gear ratio operatively connected to the first planetary gear set, and a synchronizer, wherein the synchronizer is operatively connected to the first planetary gear set and is positioned between the first and second planetary gear set; a differential operatively connected to the second planetary gear set; wherein the electrical machine selectively transmits power to the differential through the gear train, the first planetary gear set, the synchronizer, and the second planetary gear set, and wherein the synchronizer is constructed and arranged to shift the driveline module into a high range mode, a low range mode, and a neutral mode.

A transmission (G) for a motor vehicle includes an electric machine (EM1), a first input shaft (GW1), a second input shaft (GW2), an output shaft (GWA), two planetary gear sets (P1, P2, P3), and at least six shift elements (A, B, C, D, E, F). Different gears are implementable by selectively actuating the at least six shift elements (A, B, C, D, E, F) and, in addition, in interaction with the electric machine (EM1), different operating modes are implementable. A drive train for a motor vehicle with such transmission (G) and a method for operating such transmission (G) are also provided.