Abstract: A wave gear drive (1) includes an annular rigid internal gear (2), an annular flexible external gear (3) arranged inside of the annular rigid internal gear (2), and a wave generator (4) fitted inside of the annular flexible external gear. The wave generator (4) includes a rigid cam plate (41) having a predetermined outline, and a hub (43) inserted into a fitting hole (42) formed in the center of the rigid cam plate (41). A transfer-torque control mechanism for limiting the torque transferred through the wave generator (4) to the flexible external gear (3) is defined by a nut (46) that fastens the rigid cam plate (41) and the hub (42). When the torque equal to or greater than a predetermined value is transferred, a slip is generated in a rotational direction between the rigid cam plate (41) and the hub (42), thus limiting the transfer torque to a predetermined limit value. As a result, the torque limiter is not required.

Abstract: A control system controls a line pressure applied to a CVT upon taking account of a certrifugal pressure caused by a rotation of pulleys. The control system determines whether the centrifugal pressure is greater than a predeterminied value only by which the pulley transmits an input torque from an engine. When the determination is affirmative, a lower limit of a duty ratio for operating a line pressure control valve is switched from a lower limit of a linear range to 0% duty ratio. Therefore, an actual transmissiou ratio control range is expanded while preventing an undershoot of the line pressure.

Abstract: A control system for an automatic transmission includes a fluid transmission unit connected to an engine; a clutch; a hydraulic servo; output RPM detector for detecting the output RPM of the fluid transmission unit; oil pressure generator for generating the oil pressure fed to the hydraulic servo; and a control unit. The control unit includes a booster for raising the oil pressure according to preset characteristics; change rate detector for detecting the RPM change rate of the output RPM in a preset range at the application of the clutch; and a corrector for correcting the preset characteristics by comparing the detected RPM change rate and a reference RPM change rate. The change rate detector detects the RPM change rate only when the output RPM at the time of starting the engagement of the clutch is higher by a preset value than the maximum of the output RPM in the preset range.

Abstract: A frictional engaging clutch for an automatic vehicle transmission which discriminates judder which has occurred on the vehicle and controls to decrease the same. A clutch slip ratio is calculated, the calculated ratio is then converted into an ac waveform which is filtered by filters similar to a judder filter and a disturbance filter to extract frequency components of an appropriate range, and the number of times (NTEX) at which the filtered waveform peaks exceeds threshold values (appropriately set) is counted, and based on the counts, the judder is discriminated or determined. The configuration is simple and makes it possible to discriminate judder in an automatic vehicle transmission.

Abstract: The selector rings (9-11) of a gearbox are moved axially of the mainshaft (8) to engage and disengage gears (1-6) by respective pairs of push-rods (15, 16) which extend inwardly between the gears (1-6). The push-rods (15, 16) bear on oppositely-inclined faces (22) of pairs of blocks (17) which slide in slots (18) parallel to the shaft (8) and which engage respective rings (9-11) at diametrically-opposite locations. Actuation of one pair of rods (15; 16) causes their blocks (17) and the engaged ring (9-11) to move in one direction whereas actuation of the other pair causes movement in the opposite direction. The rods (15, 16) slide within mounting blocks (19) inset between pairs of the gears (1-6), and are actuated by the cam surface (26) of a longitudinally-driven rack (25). Alternatively, the push-rods (47, 48 FIG. 8) are actuated by individual hydraulic rams (45, 46).

Abstract: A controller for a drive train of a motor vehicle having an engine and an automatic transmission, includes an engine controller through which variables that influence the torque of the engine are controlled, a transmission controller through which shift processes of the automatic transmission are controlled, and an interface which connects the engine controller and the transmission controller to one another and through which data are transmitted to give the vehicle good handling. The interface is used to transmit a status signal which signals to the transmission controller that catalytic converter regeneration is taking place, and through which a shift process in the transmission is changed in the transmission controller.

Abstract: The crown wheel of a planetary gear is connected to an input shaft while the planet carrier is connected to the output shaft. The sun wheel is locked by means of a free wheel when the clutch is released. The device then operates as a reduction gear. The sun wheel rotates with the crown wheel and the planer carrier when the clutch is engaged. The axial forces (F.sub.AP, F.sub.AC), sustained by the sun wheel and the crown wheel when in gear-reduction mode, and resulting from the helical tooth configuration, tend through the stop to compress a spring and release the clutch. When in direct drive and beyond a certain torque, the clutch slips, thereby generating the above-mentioned axial forces which compress the spring and accelerate disengaging. The device operates as a reduction gear until the torque on the shaft is reduced, thereby, enabling the spring to re-engage the clutch.

Abstract: Hydrostatic transmission comprises a radial piston pump assembly having an axis of rotation and a gear motor. A hydrostatic fluid pathway extends between the gear motor and the radial piston pump such that the gear motor is fluidly coupled to the radial piston pump, wherein the gear motor comprises at least one gear which is capable of being rotatably driven by a fluid being transported along the fluid pathway. Preferably, a piston guide retains the piston heads against the corresponding slippers without requiring any kind of direct mechanical linkage to maintain such coupling. The present invention further provides a hydraulic shock absorber which absorbs pressure pulses generated by a rotating rotary cylinder block of a radial piston assembly, which may be either a pump or a motor.

Abstract: A gear shift mechanism in a transmission connecting a drive source to an output via a clutch. The gear shift mechanism acts on a plurality of gear pairs to select one thereof during a speed change when the clutch is disengaged. The gear shift mechanism has a hollow shaft which can be the input or output shaft of the transmission. One of the gears of the gear pairs are idly mounted on the hollow shaft and the other of the gears of the gear pairs are secured to the output shaft or a further shaft connected thereto. Alocating tube rotates with the hollow shaft and is slidable therein. The locating tube and hollow shaft have a plurality of angularly aligned radial holes and when one of the idler gears of the gear pairs is selected for engagement, the locating tube is displaced to align the radial holes therein with holes in the selected idler gear. Each of the radial holes slidably supports an engagement pin.

Abstract: A control for enhanced manual shifting in a computer (48) -assisted vehicular compound transmission having a main section (16A) shifted by a manually operated shift lever (31) and an engine fuel controller (36). Engine fueling will be in accordance with the operator-set throttle pedal position (THL) unless the control logic determines that such fueling will prevent acceptable engagement of a target gear ratio (GR.sub.T), in which case engine fueling will be automatically controlled to complete the shift.

Abstract: Disclosed is a powertrain used for a 5-speed automatic transmission. The powertrain includes a first compound planetary gearset and a second compound planetary gearset. The first compound planetary gearset comprises first and second simple planetary gearsets having first, second, third, and fourth operating elements, while the second compound planetary gearset comprises third and fourth simple planetary gearsets having fifth, sixth, seventh, and eighth operating elements. One of the fifth to eighth operating elements are fixedly connected to one of the first to fourth operating elements, one of the fifth to eighth operating elements are variably connected to two of the first to fourth operating elements, and one of the fifth to eighth operating elements operates as an output element. Clutches are disposed to variably connect the operating elements of the first and second compound planetary gearsets.

Abstract: A shift by wire vehicle transmission includes control methods for engaging gears after the vehicle has been at rest or coasting. When the vehicle is started from a stop or rest, a default starting gear is automatically selected. The driver can override the default gear and choose to start driving the vehicle in one gear above or below the default starting gear by manipulating a shift lever. Similarly, the driver can override the default starting gear to begin driving the vehicle in reverse. When the vehicle has been coasting, the transmission control unit chooses the next gear based upon a signal that is provided when the driver manipulates the shift lever. Depending on the indicated desire of the driver, the system controller automatically selects a gear depending upon vehicle speed and torque conditions.

Abstract: A planetary gear arrangement has two simple planetary gearsets and six selectively engageable friction torque transmitting mechanisms which are controlled to establish five forward transmission ratios and one reverse transmission ratio. One of the planetary gearsets establishes one forward ratio and the reverse ratio. The two planetary gearsets are compounded through both a continuous torque transmitting connection and a selectively engageable drive connection comprised of one of the torque transmitting mechanism during the two lowest forward transmission ratios and through the continuous torque transmitting connection during the highest of the forward transmission ratios. Both planetary gearsets are maintained in a direct drive ratio during the numerically central (third) forward ratio.

Abstract: In a continuously variable transmission which varies a speed change ratio based on a target speed change ratio which has been set according to a running condition of a vehicle, a sensor is provided for detecting the temperature of the continuously variable transmission. A shift amount of the speed change ratio due to a thermal expansion difference of parts of the continuously variable transmission is prevented by correcting the target speed change ratio based on the temperature detected by the sensor.

Abstract: A shaft retention and spacer mechanism, referred to as a button lock assembly, is installed between the ends of the axle shafts within the differential housing of a differential assembly. The end of each axle shaft includes a button-like end pad formed by an annular groove that is adapted to receive a C-clip therein for axially locating and restraining a side gear between the differential housing and the axle shaft. The button lock assembly includes a spacer block having a peripheral flange extending outwardly from its opposite lateral face surfaces so as to define a pair of open-ended retention chambers. The spacer block is disposed between the axle shafts such that the button-like end pads are positioned within the retention chambers. The button lock assembly further includes a lock cap that is secured to the spacer block for enclosing the open end of the retention chambers to surround the end pads.

Abstract: An integrated hydrostatic transaxle including a housing in which a center section is supported. The center section supports a hydraulic pump unit and a hydraulic motor unit having a motor shaft drivingly connected thereto. A differential assembly is drivingly linked to the motor shaft and is used to drive a pair of axle shafts which are supported by the housing. The differential assembly includes a rotatable gear which is maintained in frictional engagement with at least one bearing surfaces for frictionally inhibiting the rotational movement thereof.

Abstract: A method and apparatus for controllably shifting into a lower gear of a manual transmission is disclosed. A maximum downshift limit value is established and stored in a memory. The downshift speed variable of the manual transmission is set equal to the maximum downshift limit value in response to a valid control condition being determined. The manual transmission is controllably shifted into a lower gear when the engine speed is less than or equal to the downshift speed variable.

Abstract: An automatic transmission control system for an automotive automatic transmission including a speed sensor for detecting a vehicle speed of the vehicle, a load sensor for detecting a load acting on the driving torque generator, a torque sensor for detecting input torque transmitted to the automatic transmission from the driving torque generator, first working fluid pressure control communicating both a first friction coupling element's unlocking pressure chamber and a second friction coupling element's pressure chamber with the working fluid source in the hydraulic pressure control system for controlling supply of working fluid pressure to and from both the unlocking pressure chambers and a second working fluid pressure control in the fluid path communicating both the first friction coupling element's locking pressure chamber with the working fluid source for controlling supply of working fluid pressure to and from the first friction coupling element's locking pressure chamber.

Abstract: A hydrostatic transaxle axle assembly for a vehicle such as a grass mowing lawn or garden tractor comprising a housing for an internally disposed hydrostatic transmission having a variable-displacement hydraulic pump fluidly connected to a fixed-displacement hydraulic motor, the hydraulic motor being connected by differential gearing to axle shafts supported in the housing. The housing is formed by three housing members, two of which are preferably separable on a parting plane coincident with the longitudinal axes of the axle shafts. One of the housing members being provided with an opening to allow a portion of one of the other housing members to extend through, and where the extending housing member contains within its interior a number of internal fluid passages for fluidly connecting the hydraulic pump to the hydraulic motor.

Abstract: An integrated system for automatically controlling the operation of both an automated manual transmission and a multiple speed axle assembly in a vehicle drive train assembly includes a transmission actuator for operating the transmission in any one of a plurality of transmission gear ratios. The system further includes an axle actuator for operating the axle assembly in any one of a plurality of axle gear ratios. An electronic controller is provided for operating the transmission in a desired one of the plurality of transmission gear ratios and for operating the axle assembly in a desired one of the plurality of axle gear ratios to provide a desired overall gear ratio for the vehicle. To accomplish this, the electronic controller is responsive to one or more input signals that represent operating parameters of the vehicle.