Abstract: An automatic transmission comprising: a first planetary gearset of a double pinion; a second planetary gearset of a single pinion; a third planetary gearset of the single pinion, first sun gear and second sun gear being at all times linked together to constitute a first rotary member and second ring gear and third sun gear being at all times linked together to constitute a second rotary member; an input shaft; an output shaft; a first frictional element; a second frictional element; a third frictional element; a fourth frictional element; a fifth frictional element; a sixth frictional element, the six frictional elements being appropriately released or engaged to make a gear shift to a gear shift stage of at least eight forward speeds and, from among the six frictional elements, a combination of simultaneous engagements of three frictional elements achieving at least eight forward speed and one reverse speed.

Abstract: An automatic transmission includes first to third single-pinion planetary gearsets. The second ring gear and third sun gear are coupled to the first carrier and first ring gear respectively to constitute first and second rotor units. Input and output shafts are coupled to the second sun gear and third ring gear respectively. A first clutch selectively holds the first sun gear to the third carrier. A first brake selectively holds the first sun gear stationary. A second clutch selectively holds the second sun gear to the third carrier. A third clutch selectively holds the second carrier to the second rotor unit. A fourth clutch selectively holds the second carrier to the third carrier. A second brake selectively holds the first rotor unit stationary. At least eight gear ratios and one reverse gear ratio are obtained by simultaneous application of three of the clutches and brakes.

Abstract: An automatic transmission includes: a first planetary gearset including a first sun gear, a first ring gear, and a first pinion carrier; a second planetary gearset including a second sun gear, a second ring gear, and a second pinion carrier; an input shaft constantly coupled to the first sun gear; an output shaft constantly coupled to the second pinion carrier; a first rotary member constantly connecting the first ring gear and the second sun gear; a first friction element selectively connecting the first sun gear and the second ring gear; a second friction element selectively connecting the first pinion carrier and the second ring gear; a third friction element selectively interrupting a rotation of the first pinion carrier; and a fourth friction element selectively interrupting a rotation of the first rotary member, the automatic transmission attaining first to fourth forward speeds and one reverse speed.

Abstract: An automatic transmission including three single pinion planetary gearsets and six friction elements, in which an input shaft is always connected to a first sun gear of a first planetary gearset, the output shaft is always connected to a second ring gear of a second planetary gearset, a third sun gear of a third planetary gearset is always kept in a fixed state relative to a transmission case of the automatic transmission, a first ring gear of the first planetary gearset and a third pinion carrier of the third planetary gearset are always connected to each other and constitute a first rotary member, and at least eight forward speeds and one reverse speed are respectively established by simultaneous engagements of three friction elements selected from the six friction elements.

Abstract: An automatic transmission including a double pinion planetary gear unit PG1, two single pinion planetary gear units PG2 and PG3 and six frictional elements (viz., six clutches) C1 to C6 is so constructed as to establish nine forward speeds and one reverse speed by simultaneously putting selected three of the six frictional elements C1 to C6 into their engaged condition. The frictional elements C1 to C6 are of a type including mutually rotatable friction plates that cause production of an oil dragging resistance when the frictional element is under idling condition. With the simultaneously engaged condition of the three frictional elements, each speed is established with a reduced friction loss of the automatic transmission.

Abstract: An automatic transmission includes a double-pinion planetary gearset and two single-pinion planetary gearsets. A first ring gear is held stationary. A second sun gear and a third ring gear are coupled to a first sun gear and a first carrier respectively, constituting first and second rotor units. An output is coupled to a third carrier. A first clutch selectively couples a second carrier to the first rotor unit. A second clutch selectively couples the second carrier to the second rotor unit. A third clutch selectively couples an input to the second carrier. A fourth clutch selectively couples a second ring gear to a third sun gear. A fifth clutch selectively couples the second ring gear to the third carrier. A sixth clutch selectively couples the input to the third sun gear. Nine forward gear ratios and one reverse gear ratio are obtained by simultaneous application of three of the clutches.

Abstract: A control apparatus for a vehicle includes an automatic transmission configured to attain a predetermined shift-stage by releasing an engaged friction-engagement element and by engaging a released friction-engagement element; a variation-start detecting section configured to detect that a parameter which varies with a progress of inertia phase has varied; a memorizing section configured to sequentially memorize a state of the vehicle; and a learning section to configured to correct a control quantity for a next-time shift of the transmission on the basis of the state of vehicle memorized at a timing earlier by a given time interval than a timing when the variation-start detecting section detects that the parameter has varied.

Abstract: An automatic transmission including a single-pinion first planetary gearset having a first sun gear, a first ring gear and a first pinion carrier, a double-pinion second planetary gearset having a second sun gear, a second ring gear and a second pinion carrier, a single-pinion third planetary gearset having a third sun gear, a third ring gear and a third pinion carrier, an input shaft always connected to the first sun gear, an output shaft always connected to the first pinion carrier, the third sun gear always kept in a fixed state, the first ring gear and the second sun gear which are always connected to each other, the second and third ring gears which are always connected to each other, and six friction elements, at least eight forward speeds and one reverse speed being respectively established by simultaneous engagement of two friction elements selected from the six friction elements.

Abstract: When an inertia phase of an upshift of the transmission is started during a lockup clutch engagement operation, a following command oil pressure to be used during a following lockup clutch engagement operation is learned on the basis of a slip rotation speed, which is a rotation speed difference between an input side rotation speed of the torque converter and an output side rotation speed of the torque converter, at or after a start point of the inertia phase.

Abstract: An automatic transmission comprising: a first planetary gearset of a double pinion; a second planetary gearset of a single pinion; a third planetary gearset of the single pinion, first sun gear and second sun gear being at all times linked together to constitute a first rotary member and second ring gear and third sun gear being at all times linked together to constitute a second rotary member; an input shaft; an output shaft; a first frictional element; a second frictional element; a third frictional element; a fourth frictional element; a fifth frictional element; a sixth frictional element, the six frictional elements being appropriately released or engaged to make a gear shift to a gear shift stage of at least eight forward speeds and, from among the six frictional elements, a combination of simultaneous engagements of three frictional elements achieving at least eight forward speed and one reverse speed.

Abstract: An automatic transmission includes first to third single-pinion planetary gearsets. The second ring gear and third sun gear are coupled to the first carrier and first ring gear respectively to constitute first and second rotor units. Input and output shafts are coupled to the second sun gear and third ring gear respectively. A first clutch selectively couples the first sun gear to the first carrier. A second clutch selectively couples the second sun gear to the third carrier. A third clutch selectively couples the second carrier to the second rotor unit. A fourth clutch selectively couples the second carrier to the third carrier. A first brake selectively holds the first sun gear stationary. A second brake selectively holds the third carrier stationary. At least eight forward gear ratios and one reverse gear ratio are obtained by simultaneous application of three of the clutches and brakes.

Abstract: An automatic transmission including three single pinion planetary gearsets and six friction elements, in which an input shaft is always connected to a first sun gear of a first planetary gearset, the output shaft is always connected to a second ring gear of a second planetary gearset, a third sun gear of a third planetary gearset is always kept in a fixed state relative to a transmission case of the automatic transmission, a first ring gear of the first planetary gearset and a third pinion carrier of the third planetary gearset are always connected to each other and constitute a first rotary member, and at least eight forward speeds and one reverse speed are respectively established by simultaneous engagements of three friction elements selected from the six friction elements.

Abstract: An automatic transmission includes first to third single-pinion planetary gearsets. The second ring gear and third sun gear are coupled to the first carrier and first ring gear respectively to constitute first and second rotor units. Input and output shafts are coupled to the second sun gear and third ring gear respectively. A first clutch selectively holds the first sun gear to the third carrier. A first brake selectively holds the first sun gear stationary. A second clutch selectively holds the second sun gear to the third carrier. A third clutch selectively holds the second carrier to the second rotor unit. A fourth clutch selectively holds the second carrier to the third carrier. A second brake selectively holds the first rotor unit stationary. At least eight gear ratios and one reverse gear ratio are obtained by simultaneous application of three of the clutches and brakes.

Abstract: An automatic transmissions control system varies times to start a shift to securing a good response in engagement pressure for an engagement-side frictional element as well as suppressing occurrence of hydraulic pressure vibrations at low temperatures.

Abstract: A multispeed automatic transmission includes first, second and third frictional elements and has first, second and third speed stages. The first frictional element is disengaged, engaged and disengaged when the transmission assumes the first, second and third speed stages respectively. The second speed stage is established by a first speed change, and the third speed stage is established by a second speed change. The second frictional element is engaged, disengaged and disengaged when the transmission assumes the first, second and third speed change states respectively. The third frictional element is disengaged, disengaged and engaged when the transmission assumes the first, second and third speed stages respectively.

Abstract: A control apparatus of an automatic transmission includes first, second and third frictional elements, first and second shift control sections issuing a hydraulic pressure command to the first, second and third frictional elements for appointment and release thereof at primary and secondary shifts, a judging section judging a shift from a first speed stage to a third speed stage, and a third shift control section initiating the primary shift when the shift is judged, and initiating the secondary shift before an end of the primary shift while executing the primary shift when a gear ratio reaches a first predetermined gear ratio. the third shift control section compares two pressure command values of the first frictional element, respectively issued by the first and second shift control sections for the primary and secondary shifts, and selects a greater pressure command value, and outputs it to the first frictional element.

Abstract: An automatic transmissions control system varies times to start a shift to securing a good response in engagement pressure for an engagement-side frictional element as well as suppressing occurrence of hydraulic pressure vibrations at low temperatures.

Abstract: A control apparatus of an automatic transmission includes first, second and third frictional elements, first and second shift control sections issuing a hydraulic pressure command to the first, second and third frictional elements for engagement and release thereof at primary and secondary shifts, a judging section judging a shift from a first speed stage to a third speed stage, and a third shift control section initiating the primary shift when the shift is judged, and initiating the secondary shift before an end of the primary shift while executing the primary shift when a gear ratio reaches a first predetermined gear ratio. the third shift control section compares two pressure command values of the first frictional element, respectively issued by the first and second shift control sections for the primary and secondary shifts, and selects a greater pressure command value, and outputs it to the first frictional element.

Abstract: A multispeed automatic transmission includes first, second and third frictional elements and has first, second and third speed stages. The first frictional element is disengaged, engaged and disengaged when the transmission assumes the first, second and third speed stages respectively. The second speed stage is established by a first speed change, and the third speed stage is established by a second speed change. The second frictional element is engaged, disengaged and disengaged when the transmission assumes the first, second and third speed change states respectively. The third frictional element is disengaged, disengaged and engaged when the transmission assumes the first, second and third speed stages respectively.

Abstract: In a case of an electric failure caused to a traveling vehicle and when any of forward gears is held at a step S5, a comparison is made between: 1) a supposedly-engaged friction element of friction elements which is supposed to be engaged at the any of the forward gears and 2) an actually-engaged friction element of the friction elements which is sensed to be actually engaged, the sensing being based on a switch signal from a first hydraulic pressure switch 11, a second hydraulic pressure switch 12, a third hydraulic pressure switch 13, a fourth hydraulic pressure switch 14 and a fifth hydraulic pressure switch 15. When the supposedly-engaged friction element is not in accordance with the actually-engaged friction element, an electric system is determined to be in failure. In the case of the electric failure, a routine moves to a step S6 and subsequent steps for sticking the gear of an automatic transmission to a given gear.