Abstract: The transmission is constructed with a first ring gear and a third ring gear that are firmly connected. A second ring gear and a third carrier are also firmly connected. A second sun gear and a third sun gear are also firmly connected. An input shaft is connectable to a first carrier via a first clutch. The input shaft is connectable to a first sun gear via a second clutch. A third clutch is disposed between the first carrier and a second ring gear. The first carrier is connectable to the second ring gear and the third carrier via the third clutch. A first brake is provided between the first sun gear and a transmission case. A second brake is provided between the transmission case and the first ring gear as well as the third ring gear. A third brake and a one-way clutch are provided in parallel between the first carrier and the transmission case. A fourth brake is provided between the transmission case and the second sun gear as well as the third sun gear.

Abstract: A piston for an automatic transmission including a pair of mutually meshing gears such as counter drive and driven gears mounted on respective two parallel shafts, the piston including a bottom portion, and a cylindrical portion to be disposed radially outwardly of one of the mutually meshing gears, wherein the cylindrical portion has not only a cutout formed in a first circumferential part thereof for permitting mutual meshing engagement of the mutually meshing gears such that a point of the mutual meshing engagement is located within a circumference of the cylindrical portion, but also a through-hole formed in a second circumferential part thereof so that a speed sensor extends through the through-hole, for detecting the rotating speed of the above-indicated one gear disposed radially inwardly of the cylindrical portion. This arrangement of the cylindrical portion permits size reduction of the cutout, and assures sufficiently high degrees of strength and rigidity of the piston.

Abstract: An automatic transmission includes a first rotating element provided by a sun gear of a second planetary gear set, a second rotating element provided by coupling carriers of the second planetary gear set and a third planetary gear set to each other, a third rotating element provided by coupling ring gears of the second and third planetary gear sets to each other, and a fourth rotating element provided by a sun gear of the third planetary gear set. The second and third planetary gear sets are combined with a first planetary gear set so that the automatic transmission can provide seven forward gear stages by changing a combination of two engaging elements, such as clutches and brakes, for coupling or stopping the corresponding rotating elements.

Abstract: An automatic transmission includes a first rotating element provided by coupling a sun gear of a second planetary gear set and a carrier of a third planetary gear set to each other, a second rotating element provided by coupling a carrier of the second planetary gear set and a ring gear of the third planetary gear set to each other, a third rotating element provided by a ring gear of the second planetary gear set, and a fourth rotating element provided by a sun gear of the third planetary gear set.

Abstract: A lubrication structure of a transmission includes a gear chamber having an internal space storing lubricating oil, in which chamber a pressure is raised to a prescribed pressure, a gear chamber having an internal space communicating to the internal space through a communicating hole and attaining a pressure lower than the prescribed pressure, and an oil catch tank provided in the internal space at a position directly under the communicating hole and receiving the lubricating oil that flows into the internal space from the internal space through the communicating hole. With such a structure, a lubrication structure for a transmission capable of holding an oil level at a proper level with a simplified structure can be provided.

Abstract: A cylinder tube of a second hydraulic cylinder is provided separate from a first piston of a first hydraulic cylinder and integrally fixed to an input shaft. Friction members of a first clutch and friction members of a second clutch are prevented from moving in a first direction by a snap ring attached to a connecting drum. The friction members of the first clutch are friction engaged by the first piston and the friction members of the second clutch are friction engaged by a second piston.

Abstract: An automatic transmission includes a first rotating element provided by coupling a sun gear of a second planetary gear set and a carrier of a third planetary gear set to each other, a second rotating element provided by coupling a carrier of the second planetary gear set and a ring gear of the third planetary gear set to each other, a third rotating element provided by a ring gear of the second planetary gear set, and a fourth rotating element provided by a sun gear of the third planetary gear set.

Abstract: A planetary-gear-type multiple-step transmission including a stationary member, an input rotary member, an output rotary member, and first and second transmission units. The first transmission unit has first and second intermediate transmitting paths through which a rotary motion of the input rotary member is transmittable to the second transmission unit such that a speed of the rotary motion transmitted through the second intermediate transmitting path is lower than a speed of the rotary motion transmitted through the first intermediate transmitting path. The second transmission unit constitutes first, second, third and fourth rotary modules, each of which is provided by at least one of sun gears, carriers and ring gears of two planetary gear sets. The first rotary module is selectively connected to the second intermediate transmitting path, while being selectively connected to the stationary member.

Abstract: The transmission is constructed with a first ring gear and a third ring gear that are firmly connected. A second ring gear and a third carrier are also firmly connected. A second sun gear and a third sun gear are also firmly connected. An input shaft is connectable to a first carrier via a first clutch. The input shaft is connectable to a first sun gear via a second clutch. A third clutch is disposed between the first carrier and a second ring gear. The first carrier is connectable to the second ring gear and the third carrier via the third clutch. A first brake is provided between the first sun gear and a transmission case. A second brake is provided between the transmission case and the first ring gear as well as the third ring gear. A third brake and a one-way clutch are provided in parallel between the first carrier and the transmission case. A fourth brake is provided between the transmission case and the second sun gear as well as the third sun gear.

Abstract: An automatic transmission having first and second groups of successive forward-drive positions for outputting a rotary motion a speed of which is higher than the speed of a rotary motion received from an input member, the first group being established by an engaging action of a first input clutch while the second group being established by an engaging action of a second input clutch, or first and second groups of successive forward-drive positions for reducing the speed of the rotary motion received from the input member, the first group being established by an engaging action of a first input clutch while the second group being established by an engaging action of a second input clutch. The successive operating positions of the first group have respective speed ratios different from those of the second group. The automatic transmission is shiftable to a selected one of the successive operating positions of a selected one of the first and second groups.

Abstract: Of each rotating element of a second planetary gearset and a third planetary gearset, a first rotating element is constructed of a sun gear, a second rotating element is constructed of connected ring gears, a third rotating element is constructed of connected carriers, and a fourth rotating element is constructed of a sun gear. The first rotating element is connected to a case by a brake, the second rotating element is connected to the case by a brake, the fourth rotation element is connected to an input shaft via a clutch, the second rotation element is connected to the input shaft via a clutch, the first rotating element is integrally connected to a ring gear of a first planetary gearset, a third rotating element is integrally connected to an output gear, and six forward speeds from a first speed “1st” to a sixth speed “6th”, and a reverse speed “Rev” are achieved according to an operation table.

Abstract: The transmission 10 is constructed so that, in the first transmission portion 36, the rotation of the input shaft 16 is outputted to the second transmission portion 38 via the first intermediate output path M1 and the second intermediate output path M2 accelerated and rotated with respect to the first intermediate output path M1, and, in the second transmission portion 38, the first rotary element RE1 (S2 and S3) is selectively connected to the first driven gear CG1B via the first clutch C1 and is selectively connected to the second driven gear CG2B via the third clutch C3, the second rotary element RE2 (CA1 and CA2) are selectively connected to the first driven gear CG1B via the second clutch C2 and are selectively connected to the transmission case 12 operating as a non-rotating member via the first brake B1, the third rotary element RE3 (R1, R2 and CA3) is connected to the output gear 28 operating as an output rotating member, the fourth rotary element RE4 (S1) is selectively connected to the transmission

Abstract: With the automatic transmission 10-1 for vehicle according to the present embodiment, since multistage transmission of eight forward gear stages can be obtained by means of four sets of planetary gear sets 12, 16, 18 and 20, four clutches C1 through C4 and three brakes B1 through B3, the transmission can be fabricated to be light in weight and made compact, wherein the mountability thereof in a vehicle can be improved. Further, as has been made clear in FIG. 1(b), since speed change in the respective gear stages can be carried out only by a shifting action of any two of the clutches C1 through C4 and brakes B1 through B3, the speed change control can be facilitated and it is possible to prevent a shock to the transmission from occurring.

Abstract: An automatic transmission includes a first rotating element provided by coupling a sun gear of a second planetary gear set and a carrier of a third planetary gear set to each other, a second rotating element provided by coupling a carrier of the second planetary gear set and a ring gear of the third planetary gear set to each other, a third rotating element provided by a ring gear of the second planetary gear set, and a fourth rotating element provided by a sun gear of the third planetary gear set.

Abstract: A planetary-gear-type multiple-step transmission including a stationary member, an input rotary member, an output rotary member, and first and second transmission units. The first transmission unit transmits a rotary motion from an input rotary member to the second transmission unit through first and second intermediate transmitting paths such that a speed of the rotary motion transmitted through the second intermediate transmitting path is lower than that of the rotary motion transmitted through the first intermediate transmitting path. The second transmission unit constitutes first, second, third, fourth and fifth rotary elements, each of which is provided by at least one of sun gears, carriers and ring gears of three planetary gear sets. The first rotary element is selectively connected to the second intermediate transmitting path, while being selectively connected to the stationary member. The second rotary element is selectively connected to the first intermediate transmitting path.

Abstract: A multiple-step transmission including a first transmission portion including a first intermediate output path which transmits, at a first speed ratio, an input rotary motion of an input member, and a second intermediate output path which transmits the input rotary motion at a second speed ratio greater than the first speed ratio; and a second transmission portion including a 2-1, a 2-2, and a 2-3 planetary gear set each of which includes a sun gear, a carrier, and a ring gear, the 2-1, 2-2, and 2-3 planetary gear sets being partly connected to each other to provide a first, a second, a third, a fourth, and a fifth rotary element, the second transmission portion further including a first brake which selectively stops a rotary motion of the first rotary element, a second brake which selectively stops a rotary motion of the second rotary element, a first clutch which selectively connects the fifth rotary element to the second intermediate output path of the first transmission portion, a second clutch which sele

Abstract: The transmission is constructed with a first ring gear and a third ring gear that are firmly connected. A second ring gear and a third carrier are also firmly connected. A second sun gear and a third sun gear are also firmly connected. An input shaft is connectable to a first carrier via a first clutch. The input shaft is connectable to a first sun gear via a second clutch. A third clutch is disposed between the first carrier and a second ring gear. The first carrier is connectable to the second ring gear and the third carrier via the third clutch. A first brake is provided between the first sun gear and a transmission case. A second brake is provided between the transmission case and the first ring gear as well as the third ring gear. A third brake and a one-way clutch are provided in parallel between the first carrier and the transmission case. A fourth brake is provided between the transmission case and the second sun gear as well as the third sun gear.

Abstract: An automatic transmission includes a parallel-axis gear pair including a first gear having a shaft portion and a gear portion, and a second gear which meshes with the first gear; a case that has a supporting wall which is adjacent to the gear portion of the first gear and rotatably supports the shaft portion of the first gear; and a frictional engagement apparatus that includes friction members, a piston that presses on, so as to apply, the friction members, and a hydraulic chamber that holds hydraulic fluid which moves the piston in the direction of the friction members. As a result, both the shaft to shaft dimension as well as the axial dimension of the automatic transmission can be reduced.

Abstract: A vehicle planetary gear type multiple-step transmission wherein each of five rotary elements is constituted by sun gears, carriers and ring gears of three planetary gear sets, and speeds of the rotary elements are represented by respective straight lines in a collinear chart, and the first, second and third rotary elements are made stationary by respective first, second and third brakes, and the fifth, third and first rotary elements are connected to an input shaft by respective first, second and third clutches, while the third rotary element is brought to a disconnected state by fourth clutch, and the fourth rotary element is connected to an output rotary member.

Abstract: An automatic transmission of a motor vehicle includes first, second and third planetary gear sets, two clutches and three brakes. A first-speed gear stage having the largest gear ratio is established when the first clutch and the first brake are engaged, a second-speed gear stage is established when the first clutch and the second brake are engaged, a third-speed gear stage is established when the first clutch and the third brake are engaged, a fourth-speed gear stage is established when the first clutch and the second clutch are engaged, a fifth-speed gear stage is established when the second clutch and the third brake are engaged, a sixth-speed gear stage is established when the second clutch and the second brake are engaged, and a seventh-speed gear stage is established when the second clutch and the first brake are engaged.