Abstract: A shift control system is arranged such that a shift lever 201 is movable to a “P” position, an “R” position, an “N” position, a “D5” position and a “D4” position along a first shift guide path 211, it is movable also from the “D4” position to a “3/M” position along a connection shift guide path 212, and it is movable also along a second shift guide path 213, from the “3/M” position into a direction different from that of the connection shift guide path 212. When the shift lever is shifted to the “D5” position, the transmission is set into an automatic shift control with forward drive speed ratios up to the FIFTH speed ratio. When the shift lever is shifted to the “D4” position, the transmission is set into an automatic shift control with forward drive speed ratios up to the FOURTH speed ratio.

Abstract: A constant-speed running controller which sets a target throttle opening of a throttle valve such that the speed of a vehicle is at a target vehicle speed, detects an amount of accelerator pedal operation as an accelerating pedal opening, adds the set target throttle opening and the detected accelerating pedal opening to generate an opening signal as the addition result, and drives the throttle valve and controls a transmission stage of an automatic transmission in accordance with the opening signal.

Abstract: An automatic gear change controller, having a constant speed travel mode, which can transmit torque to wheels of a vehicle according to changes in the travel load of the vehicle even though a gear shift mode is changed to the manual gear shift mode. When the gear shift mode is set in the manual gear shift mode and the travel mode is set in a constant speed travel mode, a constant speed travel controller generates a downshift command signal. In this case, when the accelerator pedal is depressed beyond a predetermined amount, the gear shift stage of the automatic transmission is downshifted.

Abstract: The durability of the entire metal ring assembly is enhanced by increasing the wear life of the radially inner surface of the metal ring of the innermost layer which is the layer which is most easily fractured. A belt for a continuously variable transmission is formed by supporting a large number of metal elements on a metal ring assembly wherein multiple sheets of endless metal rings are layered. The thickness of the metal ring of the innermost layer is different from the thickness of the metal rings of layers other than the innermost layer. The thickness of the metal ring of the innermost layer is set so that the stress amplitude applied to the radially outer surface of the metal ring of the innermost layer is not more than the stress amplitude applied to the radially outer surfaces of the metal rings of layers other than the innermost layer. By setting the thickness of the metal ring of the innermost layer at 0.042 mm to 0.

Abstract: A system for controlling an automatic transmission of a vehicle which determines a downgrade or upgrade parameter based on the vehicle acceleration and selects one from among a plurality of shift maps (programs) based on the determined grade parameter to determine a gear ratio based on the selected shift program. The system includes a navigation system which stores the road information including the kinds of road. The system determines whether the vehicle runs on a relative road such an alley or a traffic jammed expressway based on the vehicle speed change, the vehicle-stopping-time and the navigation information and if it does, changes the upshift line of the level-road map in the direction in which the vehicle speed increases such that upshift is not likely to occur, or in the direction in which the vehicle speed decreases such that the upshift is more likely to occur, thereby enhancing driveability.

Abstract: By defining the contact ratio obtained by dividing the lateral width of a saddle surface of metal elements of a metal belt for a continuously variable transmission by the lateral width of a metal ring, the transmission capacity and durability of the metal belt can be enhanced. By gradually increasing the width of the metal ring in a state in which the lateral inner edges of the metal ring are in contact with the neck parts of the metal elements so as to gradually decrease the contact ratio, accompanying it the percentage change in the power transmission capacity gradually increases from the negative side and changes positive at a predetermined contact ratio.

Abstract: The relation of the length h1 of the V surface of each metal element to the saddle primary thickness h2 is determined such that the strength of the metal element for the Hertz's pressure generated on the V surface 2 from the normal force P which acts on the V surface 2 when the element engages in the V-shaped groove of a pulley and the strength for the bending moment which is produced by the normal force P on the saddles 1 of the metal element are made substantially equal to each other. Also, the relation of the length of the V surface to the saddle primary thickness is determined such that the fatigue life by the Hertz's pressure which acts on the V surface and the fatigue life by the bending moment which acts on the saddles are made substantially equal to each other. The length h1 of the V surface, which is determined in the above mentioned ways, can be about 0.26-1.0 of the saddle primary thickness h2.

Abstract: A control system for an automatic vehicle transmission having a parking lever provided at a position close to the vehicle operator seat of the vehicle to be manipulated by the vehicle operator and mechanically connected to a parking mechanism connected to the transmission output shaft, for enabling to operate the parking mechanism to lock the output shaft such that a parking range is established, and a range selector comprising an electric switch provided at a position close to the vehicle operator and electrically connected to a hydraulic mechanism of the automatic transmission such that any of the other gear ranges can be selected by the vehicle operator, thereby enlarging free space around the vehicle operator seat by removing the console-type range selector, without needing an actuator such as an electric motor for moving the manual valve or the parking mechanism so as to eliminate the problem when the on-board battery is discharged.

Abstract: A system for controlling an automatic transmission mounted on a vehicle, including an automatic mode in which a gear is retrieved from predetermined gearshift characteristics by the detected vehicle speed and the engine load and a manual mode in which a gear is designated by a device manually operated by a vehicle driver. In the system, a temperature in an exhaust pipe of the vehicle is estimated based on the detecting operating conditions and the gear designated in the manual mode is corrected to upshift by one gear, if the estimated exhaust pipe temperature is found to exceed a predetermined temperature, thereby improving avoidance of the occurrence of excessive thermal load of components in the vicinity of the exhaust pipe, and that, by not conducting forced upshift until such time, fully exploits the features of the manual mode and, by this, makes the product more appealing to customers.

Abstract: An oil sump 44 and a second oil supply passage 45, which are to lead lubrication oil from a first oil supply passage 43 to where lubrication is needed, i.e., to gears and a clutch, are formed in a sun gear 21, which has a sufficient strength as a torque transmission member. In comparison with another case where an oil sump and an oil supply passage are provided in a relatively thin member such as a sleeve 3, the unfavorable effect of stress concentration around the oiling aperture and of deterioration of strength from the reduced thickness can be greatly minimized. In addition, the fabrication of the oil sump and the oil supply passage is much easier and cost-effective than if they were to be provided in a thinner member.

Abstract: A system for controlling gear (gear ratio) shifting in an automatic transmission mounted on a vehicle, including a shift control means for generating a shift command to upshift from one gear (gear ratio) currently established to a next gear (gear ratio) by determining a command to the solenoid valves to discharge the pressurized oil from the frictional engaging elements that establish the current gear (gear ratio) so as to slip-control the frictional engaging elements, and to charge the pressurized oil to the frictional engaging elements that establish the next gear (gear ratio) to be shifted to.

Abstract: A hydraulic seal system includes a seal ring groove and a seal ring mounted in the seal ring groove. The seal ring and seal ring groove are rotatable relative to each other, and have sealing sides, respectively, which are put into pressure contact with each other by a sealing hydraulic pressure. The seal ring is made of a synthetic resin to have a fixed elasticity. The sealing side of the seal ring is formed into a convex curved surface with its radially central portion raised, so that when a hydraulic pressure is applied, the sealing side can be compressedly deformed to define a hydraulic pocket. Thus, the formation and retaining of an oil film at the pressure contact portions of the sealing sides is promoted.

Abstract: A planetary gear transmission comprises first, second and third planetary gear trains G1, G2 and G3 which are disposed coaxially with one another and respectively in this order from an input member. The first and second ring gears R1 and R2, which are fixedly retainable by a first brake B1, are disengageably connected to the input shaft 1 through a first clutch K1. The first sun gear S1 is also disengageably connected to the input shaft 1 through a third clutch while the first carrier C1 and the second sun gear S2 are connected to the output shaft 7. Furthermore, a connecting shaft 4 is disposed away from and in parallel with the axis of the first, second and third planetary gear trains G1, G2 and G3, and one end of the connecting shaft is connected to the input shaft 1 through a first connecting gear train 2 and 3 while the other end of the connecting shaft is connected to the third sun gear S3 through a second connecting gear train 5 and 6.

Abstract: A metal V-belt type continuously variable transmission in which the length of a side of an element contacting with a V-face of a pulley is shortened to increase a ratio range. If the element side length of a metal element is represented by L, the angle of the V-face of the pulley is represented by .alpha., and the hertz surface pressure between the pulley and the metal element is represented by .sigma..sub.H, the following relation is established: L .varies. sin .alpha./.sigma..sub.H.sup.2. When the hertz surface pressure .sigma..sub.H is determined to be between an upper limit value defined by the wear durability of the metal element and a lower limit value defined by the limit tensile force of an endless belt, the element side length L can be decreased by decreasing the angle of the V-face of the pulley. Thus, the distance through which the metal element can be moved radially of the pulley is increased to increase the ratio range.

Abstract: A shift control for a shift-down operation is executed by carrying out the following stages in order: an off-going range releasing stage STO1 which quickly lowers the engagement actuation pressure of the off-going engaging element to an engagement-releasing pressure; an off-going range controlling stage STO2, STO3 and STO4 which sets the engagement actuation pressure of the off-going engaging element to a pressure a little higher than the engagement-releasing pressure; an on-coming range void-stroke-clearing stage STR1 which sets the engagement actuation pressure of the on-coming engaging element to a predetermined high-pressure necessary for clearing the void stroke; an on-coming range waiting stage STR2 and STR3 which sets the engagement actuation pressure of the on-coming engaging element to a stand-by pressure necessary for retaining the on-coming engaging element in stand-by condition prior to engagement; an off-going range final stage which releases the off-going engaging element completely; and an on-c

Abstract: A control for shifting from an off-going speed range to an on-coming speed range comprises an off-going range releasing stage, an on-coming range void-stroke-clearing stage, an on-coming range engaging stage and an on-coming range final stage. During the off-going range releasing stage, an off-going engaging element is released in response to a shift command signal. During the on-coming range void-stroke-clearing stage, the engagement-actuation pressure of the on-coming engaging element is set at a predetermined high-pressure for a predetermined time period after the shift command signal is generated, whereby the void stroke of the on-coming engaging element is cleared. During the on-coming range engaging stage, after the completion of the on-coming range void-stroke-clearing stage, the on-coming engaging element is engaged. During the on-coming range final stage, following the on-coming range engaging stage, the on-coming engaging element is engaged completely.

Abstract: In a metal V-belt type continuously variable transmission having a driving pulley and a driven pulley, the inclination angle .alpha. of a V-groove in the pulleys is set in a range represented by tan.sup.-1 .mu.a<.alpha.<tan.sup.-1 .mu.s, wherein .mu.s represents the static friction coefficient between the pulley and an endless belt, and .mu.a represents the dynamic friction coefficient between the pulley and the endless belt. In a conventional metal V-belt type continuously variable transmission, the inclination angle .alpha. is set in a range represented by .alpha.>tan.sup.-1 .mu.s. If the transmittable torque Tin is increased, the tensile force of the endless belt is increased to produce slipping between the endless belt and the pulley. However, according to the present invention, by decreasing the inclination angle .alpha. to reduce the tensile force of the endless belt, the transmittable torque Tin can be increased while preventing slipping of the endless belt.

Abstract: An automatic transmission includes a frictionally engaging element for establishing a predetermined speed range. This predetermined speed range may be a second or higher speed range, and it is set temporarily in N-D squat control and also used for establishing a reverse range. In this transmission, engagement-actuation control of the frictionally engaging element for establishing the predetermined speed range which is executed when a shift is made from a N range to a R range comprises a plurality of control stages. When a shift to the R range is made via the N range following a N-D shift, a shift control apparatus detects the engagement condition of the the frictionally engaging element for establishing the predetermined speed range, selects one of the control stages in correspondence with the engagement condition, and initiates the engagement-actuation control of the frictionally engaging element from the control stage selected, so as to execute an engagement control for establishing the reverse range.

Abstract: An automatic transmission includes a plurality of power transmitting gear trains making up a combination of forward power transmitting paths that can be selected one at a time, a plurality of frictional engaging elements for selecting one of the forward power transmitting paths at a time, and a one-way clutch for establishing a lowest-speed gear position among the forward power transmitting paths. When a gear shift is to be made from a neutral gear range to a forward gear range, one of the frictional engaging elements which is mechanically coupled to the one-way clutch is preliminarily engaged. When the gear shift can be made from the neutral gear range to the forward gear range, one of the frictional engaging elements for establishing the starting gear position starts being engaged, and thereafter those frictional engaging elements which are not necessary to establish the starting gear position are released.

Abstract: The torque detection system for a continuously variable transmission for a vehicle having a dual-mass flywheel connecting an output of an engine mounted on the vehicle to the transmission and a start clutch for engaging/disengaging the transmitted power to the vehicle wheels. The dual-mass flywheel comprises of two flywheel components coupled by a torsion spring. Rotational speeds of the two flywheel components are detected and a phase angle therebetween is then calculated. A torque estimated to be input to the start clutch is determined by retrieving predetermined characteristics defining a static torque set with respect to the phase angle. When the vehicle is braked to stop in engine idling state, the clutch oil pressure is determined based on the calculated torque.