Abstract: In a disengagement side control, in a power on state, a disengagement side pressure P.sub.W is output, P.sub.W being set higher than a base pressure dependent on input torque, and a disengagement side frictional engagement element is engaged and maintained. In a power off state, a disengagement side pressure lower than the base pressure is output, and the disengagement side frictional engagement element slips. In the disengagement side control, when the vehicle driving state is changed from the power off state to the power on state, the disengagement side pressure P.sub.W is changed from that for a slip state to that for a maintain state.

Abstract: An automatic transmission establishing multiple gear stages includes a reduction planetary gear, at least two clutches transmitting a decelerated rotation transmitted from the reduction planetary gear, and a planetary gear set inputted the decelerated rotation transmitted through the two clutches. The reduction planetary gear and the two clutches are arranged in one side of the planetary gear set. The reduction planetary gear is arranged between the clutches.

Abstract: An automatic transmission includes a planetary gear set inputted a decelerated rotation and a non-decelerated rotation and outputting a plurality of shift rotations, a reduction planetary gear, an input shaft, first and third clutches which are able to engage/disengage for connecting the input shaft through the reduction planetary gear to two different decelerated rotation input elements of the planetary gear set individually, and a second clutch which is able to engage/disengage for connecting the input shaft to a non-decelerated rotation input element. The first clutch, the third clutch and the reduction planetary gear are arranged together, and the second clutch is arranged in the other side of the planetary gear set.

Abstract: There is provided control over transmission stages which suppresses unnecessary shifts to a higher speed based on road information stored in a navigation system to allow smooth acceleration. An intersection ahead of the vehicle in the traveling direction is detected based on the road information stored in the navigation system and, when the vehicle is decelerated as it approaches the intersection, an optimum transmission stage for acceleration is selected in advance in accordance with the speed of the vehicle by predicting the acceleration to be performed when exiting the intersection. This eliminates the need for a shift to a lower speed before effecting acceleration by pressing the accelerator and thereby ensures smooth acceleration.

Abstract: A neutral start switch has a base on which stationary contacts are arranged and a rotor on which movable contacts capable of contacting the stationary contacts are disposed. The stationary contacts include reverse lamp contacts connected to a reverse lamp lighting circuit, position stationary contacts connected to a position signal circuit provided in an electronic control device, and starter stationary contacts connected to a starter motor driving circuit. The contacts are arranged so that contact portions of the movable contacts that contact the reverse lamp stationary contacts are different from contact portions of the movable contacts that contact the other stationary contacts, thereby preventing carbonized powder produced by spark at the time of the closure and opening of the reverse lamp contacts from causing a contact failure of another contact.

Abstract: When a vehicle driving state of an automatic transmission is changed to a power-off state from a power-on state during a down shift involving the disengagement of one friction element and the engagement of another friction element, a disengagement side pressure PA is reduced rapidly by a feedback control based on the change in gear ratio because of a reduction of an input torque. The disengagement side pressure control is unable to complete change of the gear ratio to complete the down shift. When the disengagement side pressure is reduced to a value less than a return spring load pressure PG or when the gear ratio change has not achieved a basic value in a predetermined time, the down shift control is changed from primary control by the disengagement side pressure control to primary control by an engagement side control so that the gear ratio change is completed by control of the engagement side pressure.

Abstract: A parking control mechanism to prevent generation of noise and shock when a parking range is released after a vehicle has been parked so that a driver does not feel uncomfortable. A parking apparatus of an automatic transmission has a parking gear; a parking pole swingably disposed and provided with a claw arranged to selectively be engaged with a tooth space of the parking gear; an engagement inhibition device movably disposed and arranged to be moved to an inhibition position for inhibiting engagement between the claw and the tooth space and to an inhibition release position for releasing the inhibition of the engagement; and an engagement inhibition release device for moving the engagement inhibition device to the inhibition release position in synchronization with the rotation of the parking gear. After a residual torque existing between the parking gear and drive wheels has been released, the claw and the tooth space are engaged with each other.

Abstract: A lubricant control apparatus for an automatic transmission including a lubricating unit for feeding the lubricating oil to the portions of a speed change mechanism so that the heat to be generated in the speed change mechanism may be absorbed and recovered by the lubricating oil. The lubricant control apparatus includes a detector that detects the acting state of the speed change mechanism; a determiner that determines a necessary lubricating oil flow on the basis of the calorific value in the speed change mechanism, the calorific value being calculated from the detected acting state of the speed change mechanism; and a structure for feeding the lubricating oil to the speed change mechanism on the basis of the determined necessary lubricating oil flow. The lubricant control apparatus feeds an optimum lubricating oil flow according to the acting state of the speed change mechanism.

Abstract: An infinitely variable transmission has a gear neutral (GN) point and serves as an output member by torque circulation. When a pulley ratio thereof is within a predetermined range from the GN point, a coasting state occurs which may hinder smooth torque transmission based on the transmission efficiency and generate a great engine braking effect (failure in the transmission resulting from the coasting state) based on a large gear ratio. When the pulley ratio assumes a predetermined value that may cause failure in transmission resulting from the coasting state, upon release of the accelerator pedal, an electronic throttle system performs control such that the engine outputs a predetermined torque. Thus a positive driving state is always established. In this state, the continuously variable transmission (CVT) is shifted in the upshift direction to escape rapidly from a range defined by the pulley ratio of the predetermined value.

Abstract: A shift control system of an automatic transmission sets a predetermined gear stage by applying a first frictional engagement element and releasing a second frictional engagement element. A pressure regulating mechanism regulates an oil pressure to be fed to or drained from the first frictional engagement element. A failure detector detects a failure of an apparatus to participate in the regulation and control of the oil pressure which is to be fed to or drained from at least one of the first and second frictional engagement elements. A gear stage inhibitor inhibits the setting of the predetermined gear stage if the failure is detected by the failure detector.

Abstract: In an automatic transmission, a small-capacity second clutch that does not engage for reverse drive is mounted forward of a counter drive gear, and the other engaging elements of relatively larger capacity, that is, first and third clutches and first to third brakes, are disposed rearward of the counter drive gear, so that an axially extending space is formed between the counter drive gear and the second clutch, which space is utilized to accommodate a parking gear. Such an arrangement of engaging elements allows the counter shaft to be placed closer to the input shaft without the parking gear interfering with the second clutch, thereby enabling a more compact automatic transmission. Furthermore, since there is no need to relocate the counter drive gear rearward, the length of the counter shaft can be reduced, thereby enabling still greater compactness.

Abstract: A control system for a vehicular automatic transmission includes a speed change mechanism including an output element that is connected to the drive shaft of a vehicle to transmit power, and a rotary element connected to the output element. A control system for the speed change mechanism is also provided. The control system includes a hydraulic servo actuated brake for retaining the rotary element to check the rotation of the output element in a vehicle roll back direction. The brake includes a band brake that establishes different application forces depending on whether the brake operates by a self-energizing action or a de-energizing action according to the rotational direction of the rotary element.

Abstract: A control apparatus executes appropriate speed change control under any operating conditions encountered during an up-shift by change-over, without requiring an increase in control logic. Engagement side hydraulic pressure is swept up as a result of an arithmetic operation in torque phase speed change control. Disengagement side hydraulic pressure is calculated by initial speed change control, dependent on the engagement side hydraulic pressure. The engagement side hydraulic pressure is directly controlled and the disengagement side hydraulic pressure is indirectly controlled, i.e. responsive to the engagement side control. Consequently, the same control scheme can be executed regardless of power-on state or power-off state and regardless of vehicle operating conditions.

Abstract: When a vehicle is halted with the transmission in a forward drive range, an input clutch is disengaged to enhance the fuel efficiency and, at the same times a hill-hold brake is engaged to prevent the vehicle from rolling backward on a steep up-slope. At that time, the hydraulic pressure P.sub.C-1 of the input clutch C1 is gradually reduced by .DELTA.P.sub.CIR (P.sub.C-1 =P.sub.C-1 -.DELTA.P.sub.CIR) while the hydraulic pressure P.sub.B-1 of the hill-hold brake B1 is increased gradually so as to satisfy an equation P.sub.B-1 =K1+K2 X e where .DELTA.P.sub.cir is a change in hydraulic pressure which is required for gradually disengaging the first clutch C1, K1 is a hill-hold brake pressure at which braking resistance begins, K2 is hill-hold brake pressure producing a fully braked condition, and e is the input/output rotational-speed ratio of a torque converter Subsequently during start of vehicle movement, the hydraulic pressure P.sub.C-1 of the input clutch C1 is gradually increased (P.sub.C-1 =p.sub.C-1 +.

Abstract: In power-on, high-vehicle-speed and high-torque conditions, a control unit sets a torque allotment ratio such that a main clutch bears all the torque. Thereby, the input shaft rotational speed is increased by controlling solely the main clutch releasing pressure. In power-on and low-torque or low-vehicle-speed conditions, the control unit sets a torque allotment ratio for the main clutch torque and the sub-clutch torque to 1:1. Thereby, control of the main clutch releasing pressure and control of the sub-clutch engaging pressure simultaneously proceed in parallel to produce a change in the input shaft rotational speed without a time lag. The hydraulic control apparatus thus conducts proper downshift control for a shift involving clutch engagement changeover, under all vehicle running conditions, without need for additional control logic.

Abstract: A control system for an automatic transmission having a running status detector for detecting the running status of a vehicle including an input torque from an engine; a running resistance estimator for estimating a running resistance on the basis of the running status of the vehicle; a running resistance comparator for comparing the estimated running resistance and a preset reference value; and a shift characteristic changing device for changing shift characteristics in accordance with the comparison result of the running resistance comparator. The automatic transmission control system further has a temperature sensor for detecting a temperature relating to the temperature of the engine and a decision device for determining a specific engine running status, in which the output of the engine drops, on the basis of an output signal coming from the temperature sensor. The running resistance comparator changes the reference value in accordance with the determination of the decision device.

Abstract: A hydraulic servo unit for a vehicular power transmission system having a helical gear, including a clutch for connecting predetermined rotary elements to each other and a hydraulic servo for applying the clutch, the hydraulic servo including a cylinder, a piston fitted in the cylinder, a push member abutting against the piston through a bearing for transmitting the push force of the piston to the clutch, and a return spring for the piston, one of the rotary elements including a reaction member opposed to the push member for transmitting the push force of the piston to a case, and the cylinder is a stationary cylinder formed in the case. Further, the return spring is arranged between the push member and the reaction member and is loaded to apply a load higher than the thrust force of the helical gear, as acting upon the reaction member.

Abstract: An automatic transmission for a vehicle with a reverse gear brake that includes a case. A predetermined rotational element, having gear teeth and an axis, is disposed within the case. The predetermined rotational element only operates as a rotational element when achieving a reverse gear mode. A brake has a gear member. The gear member is attached to the case so that it cannot rotate relative to the case, but is movable along the axis of the predetermined rotational element so that it can be engaged and disengaged with the teeth of the predetermined rotational element. The predetermined rotational element is fixed to the case so that it cannot rotate relative to the case when the gear teeth engage the gear member.

Abstract: A hydraulic servo-mechanism for an automatic transmission, including a hydraulic servo for applying a band brake to engage a band to a drum. The hydraulic servo includes a rod which is selectively positionable to an apply position for applying the band brake, a standby position in which the rod is retracted by a predetermined extent in a release direction from the apply position, and a retracted position in which the rod is further retracted in the release direction from the standby position to release the band brake.

Abstract: A vehicular automatic transmission for establishing a plurality of forward gear stages, includes: a transmission case; an input shaft; a transmission mechanism connected to the input shaft and including a plurality of transmission elements; an output shaft connected to the transmission mechanism; first and second clutches at opposite ends of the transmission mechanism and drivably connecting the input shaft with at least one of the transmission elements; and first and second hydraulic servos for applying the first and second clutches responsive to feed of an oil pressure. The transmission case encloses the transmission mechanism, the clutches and the hydraulic servos, and includes axial end walls forming cylinders for the hydraulic servos.