Abstract: Whether the load on the automobile is normal or heavy or whether the automobile is in a normal, oversteering or understeering condition is detected by a rising-up performance of the yaw rate in the initial transient state of steering from a comparison of an actual yaw rate detected by a sensor and a standard yaw rate calculated from vehicle speed and steering angle, and the speed stage shifting of the automatic transmission is modified according to the result of the comparison so as to compensate for a change of load or a deviation of steering performance from a normal condition.

Abstract: A control system of an automatic transmission for determining and setting a gear stage on the basis of at least two of the parameters including a vehicle speed and a throttle opening. The control system comprises: a first detector for detecting a first parameter; a second detector for detecting a second parameter; a gear stage memory for determining and storing speed stage areas for holding the gear stages individually in terms of the first and second parameter and any two speed stage areas in a partially overlaid manner; a shift decider for determining a shift to be executed, on the basis of the first parameter outputted from the first detector, the second parameter outputted from the second detector, and the stored content of the gear stage memory; and a gear stage determiner for determining a gear stage to be set, if there are a plurality of gear stages determined by the first parameter and second parameter detected, at any of the gear stages.

Abstract: An automatic transmission which includes a device for selecting and temporarily setting such one of other speed stages, if any, between a present speed stage and a target speed stage as can have a small number of fluctuating revolutions of rotary members of planetary gear sets of the automatic transmission and two or less frictional engagement elements to be switched.

Abstract: A speed changing gear device for an automatic transmission, comprising a main gear assembly for providing a plurality of operating positions, and an auxiliary gear assembly for providing a direct drive position and a speed changing drive position. The main gear assembly includes a single-pinion type first planetary gear unit having a first sun gear, a first planetary gear, a first ring gear and a first carrier, and a single-pinion type second planetary gear unit having a second sun gear, a second planetary gear, a second ring gear and a second carrier. The auxiliary gear assembly includes a third planetary gear unit having a third sun gear, at least one third planetary gear, a third ring gear and a third carrier. The first carrier and second ring gear are fixed to each other, or selectively connected to each other by a first clutch. The first and second sun gears, and the first sun gear and second carrier are selectively connected to each other by a second and a third clutch, respectively.

Abstract: A shift control system and method for use in an automatic transmission includes a plurality of frictional engagement elements and a gear train settable to a plurality of speed stages of different gear ratios according to the engagement/release states of the frictional engagement means and having a plurality of different engagement/release combinations for the frictional engagement elements to set a predetermined one of the speed stages. A shift decision unit decides a shift to be performed. A speed stage selection determines a speed stage to be set after the shift. An engagement/release pattern selects and outputs one of the engagement/release combinations of the frictional engagement elements for setting a speed in which either the current speed stage or the speed stage to be set after the shift is the predetermined speed stage, wherein two or less of the frictional engagement elements have their engagement/release states switched during the shift.

Abstract: A shift control system for controlling the shifting of a vehicular automatic transmission including a plurality of frictional engagement members and having a plurality of engage/release combinations of the frictional engagement members for setting a predetermined one of gear stages. The shift control system comprises: a changer for effecting a change-over between an automatic shift mode for shifting the automatic transmission automatically on the basis of the running condition of the vehicle and a manual shift mode for shifting the same manually on the basis of the manipulation of the driver; and an engage/release pattern selector for selecting, in the manual shift mode, an engage/release combination of the frictional engagement members, which is different from the combination selected in the automatic shift mode, as that for setting the predetermined gear stage.

Abstract: A shift control system for use in an automatic transmission which includes a plurality of frictional engagement components, and a gear train adapted to set a plurality of speed stage having (Tables 1 and 3) different gear ratios in accordance with the combination for engagement/release of the frictional engagement components and enabled to select a combination for engaging and releasing any of the frictional engagement components as that for engagement/release of the frictional engagement components for setting any of the speed stages.

Abstract: A shift control system for use in an automatic transmission having a gear train to be set to a plurality of gear stages of different gear ratios in accordance with the engagement/release states of a plurality of fricitional engagement devices. The gear train is enabled to set a predetermined gear stage in accordance with plural kinds of combination of the engagement/release of the frictional engagement devices. The shift control system comprises: an input torque detector for detecting input torque to be inputted to the gear train; a torque evaluator for evaluating the level of the input torque; and an engagement/release pattern selector for selecting the combination of engagement/release of the frictional engagement devices for setting the predetermined gear stage, on the basis of the result of the input torque evaluated by the torque evaluator.

Abstract: A shift control system for use in an automatic transmission which comprises: a plurality of frictional engagement components; and a gear train adapted to set a plurality of speed stages having different gear ratios in accordance with the combination for engagement/release of the frictional engagement components and enabled to select a combination for engaging and releasing any of the frictional engagement components as that for engagement/release of the frictional engagement components for setting any of the speed stages.

Abstract: A shift control system for a vehicular automatic transmission including a gear train to be set to a plurality of gear stages in accordance with the engaged or released states of a plurality of friction devices.

Abstract: A shift control system for an automatic transmission which can be set both at main gear stages selected on the basis of the running state of a vehicle and at intermediate gear stages having gear ratios intermediate between those of the main gear stages. The shift control system comprises: a running state detector for detecting the running state; a shift decider for deciding a main gear stage to be set, on the basis of the running state detected; a condition decider for deciding whether or not a shift between the main gear stages decided by the shift decider satisfies a predetermined condition; and an intermediate stage setter for deciding an intermediate stage to be set in place of the main gear stage, which was decided by the shift decider, on the basis of the result decided by the condition decider.

Abstract: A speed changing gear device for an automatic transmission, comprising a main gear assembly for providing a plurality of operating positions, and an axiliary gear assembly for providing a direct drive position and a speed changing drive position. The main gear assembly includes a single-pinion type first planetary gear unit having a first sun gear, a first planetary gear, a first ring gear and a first carrier, and a single-pinion type second planetary gear unit having a second sun gear, a second planetary gear, a second ring gear and a second carrier. The auxiliary gear assembly includes a third planetary gear unit having a third sun gear, at least one third planetary gear, a third ring gear and a third carrier. The first carrier and second ring gear are fixed to each other, or selectively connected to each other by a first clutch. The first and second sun gears, and the first sun gear and second carrier are selectively connected to each other by a second and a third clutch, respectively.

Abstract: An automatic transmission wherein a gear train is constituted by three single pinion type planetary gear sets, provided with a first planetary gear set having a first sun gear, a first ring gear, and a first carrier holding pinion gears meshing with the first sun gear and the first ring gear, a second planetary gear set having a second sun gear, a second ring gear which is normally or selectively connected with the first carrier, and a second carrier holding pinion gears meshing with the second sun gear and the second ring gear, a third planetary gear set having a third sun gear normally or selectively connected to the second carrier, a third ring gear which is continuously connected with the first carrier, and a third carrier holding pinion gears meshing with the third sun gear and the third ring gear and connected to the output shaft, a first clutch means which selectively connects the input shaft and the first ring gear, a second clutch means which selectively connects the first sun gear and the second car

Abstract: An automatic transmission includes a plurality of frictional engagement means and a gear train including a plurality of rotary members and adapted to be set to a plurality of speeds of different gear ratios in accordance with the engagement/disengagement statuses of the frictional engagement means. The gear train has a plurality of kinds of combination patterns of engagement/disengagement of the frictional engagement means for setting a predetermined speed and the number of revolutions of any of its rotary members can vary according to which of the engagement/disengagement patterns is selected. Speed control means is provided for selecting one of the combination patterns of the frictional engagement means for setting the predetermined speed so as to decrease the fluctuating number of revolutions of the rotary members.

Abstract: A shift control system for an automatic transmission comprises: a gear train including a plurality of planetary gear sets having rotary components, an input shaft and an output shaft; a plurality of clutches for selectively connecting either the rotary components of the planetary gear sets with each other or the rotary components and the input shaft; and a plurality of brakes for holding the rotary components selectively in immovable states, any one of the planetary gear sets being adapted to take no part in the transmission of torque at one gear stage.

Abstract: A planetary gear device having a first and a second single-pinion planetary gear unit and a third double-pinion planetary gear unit, which are coaxially disposed so as to provide different speed reduction ratios. The three gear units have respective first, second and third sun gears, respective first, second and third ring gears, and respective first, second and third carriers rotatably supporting planetary pinions. The first and second sun gears are fixed together or selectively connectable to each other, and the first carrier, second ring gear and third carrier are fixed together or selectively connectable to each other. Further, the second carrier and the third sun gear are fixed together or selectively connectable to each other. The present arrangement allows shifting operations of the gear device, without concurrent disengagement and engagement of different clutches.

Abstract: A gear train for changing the rotational speed of an input shaft to transmit the resultant rotation to an output shaft consists of single pinion type first and third planetary gear sets and a double pinion type second planetary gear set. Ring gears of these three planetary gear sets are normally or selectively interconnected to each other, a carrier of the first planetary gear set is normally or selectively connected to a sun gear of the third planetary gear set, a sun gear of the first planetary gear set is normally or selectively connected to a sun gear of the second planetary gear set, and the sun gear of the second planetary gear set is normally or selectively connected to the carrier of the first planetary gear set, whereby at least five forward speeds and one reverse are permitted to be set.

Abstract: In shifting speed stages of an automatic transmission by selective engagement and disengagement of friction engaging means, first and second patterns of combination of engagement and disengagement of the friction engaging means are prepared for a certain one speed stage so that a certain one of the friction engaging means bears a first magnitude of torque under the first pattern and a second magnitude of torque greater than the first magnitude of torque under the second pattern, and speed stage shifting to or from the first pattern is carried out through the second pattern.

Abstract: A shift control system and a system control method for use in an automatic transmission includes: an input shaft, an output shaft, a gear train including a plurality of revolving components and arranged between the input shaft and the output shaft, a plurality of clutches for connecting either the input shaft and any of the revolving components or the revolving components selectively, a plurality of brakes for stopping revolution of the revolving components selectively, and a one-way clutch belonging to any of the clutches and the brakes. Any of the speed stages is set according to at least two of a combination pattern of engagement/release of the clutches and brakes for engaging the one-way clutch and a combination pattern of engagement/release of clutches and brakes for releasing the one-way clutch. The combination patterns are always selected so as to switch the one way clutch.

Abstract: A first and a second rotary member such as outside or inside clutch member arranged as axially juxtaposed and radially expanded to rotate individually about a common axis in a transmission for a vehicle are separately torque-transmittingly connected with a first shaft member and a hollow second shaft member coaxially and telescopingly disposed around the first shaft member to be respectively in an individually torque-transmitting relationship by first external splines formed at an outer periphery of an end portion of the first shaft member axially extending out of an open end of the second shaft member being axially placed into engagement with first internal splines formed at an inner periphery of a central bore formed in the first rotary member, while second external splines formed at an outer periphery of an end portion of the second shaft member adjacent the open end thereof are axially placed into engagement with second internal splines formed at an inner periphery of a central bore formed in the second r