Abstract:
A drive train controller of a motor vehicle has an engine controller for controlling the variables that influence the torque of the engine. The drive train controller also includes a transmission controller for controlling the gear shift operations of the automatic transmission. The transmission controller includes a detection circuit for determining the respective driving situation of the motor vehicle. The transmission controller changes the transmission ratio in a manner that is adaptively matched to the dynamics of the determined driving situation and/or the driver characteristics.
Abstract:
The present invention is directed toward a method to digitally control a transfer case through a digital data bus to provide synchronized low to high shift capabilities in vehicles that employ a controller area network (CAN) system. In addition, a transfer case that can be digitally controlled in a vehicle with a controller area network (CAN) system to provide synchronized low to high shifts is also disclosed.
Abstract:
A transmission controller determines a requested engine torque value. For an upshift the requested engine torque value is determined as a function of slippage of one of an off-going clutch. For a downshift, the requested engine torque value is determined as a function of actual sensed engine torque. The requested torque value is sent to an engine controller which controls the engine so that the engine generates the requested engine torque. Then the appropriate transmission clutches are swapped to complete the requested shift while the engine torque is controlled. The engine controller also limits engine torque to the requested engine torque value.
Abstract:
The present invention provides a system and method for controlling engine torque when shifting from an idle state in an automatic transmission, in which the system and method improve, in a simple manner, a shift feel and a durability of friction elements such as clutches in the transmission. If idle conditions are satisfied and a change in a shift range by a shift lever is detected, an opening degree of a throttle valve and an engine speed are detected, and an engine torque control value is calculated from a mapping table established for the shift range change by the shift lever is positioned, after which engine torque is controlled based on the engine torque control value.
Abstract:
A control apparatus of an automatic transmission capable of achieving a smooth change of output shaft torque to torque which can be generated by a friction clutch, thus enabling a smooth gear change even if the output shaft torque is high at the gear change. If the output shaft torque exceeds limit transmission output shaft torque obtained by multiplying a torque capacity of the friction clutch by a gear ratio provided for the friction clutch when a gear change command is issued in the automatic transmission, engine torque is controlled so as to make the output shaft torque decreased to the limit transmission output shaft torque, and then the engine torque control is switched when the output shaft torque decreased to the limit transmission output shaft torque to start the gear change operation.
Abstract:
If a throttle valve is fully-closed, it is determined whether or not a transmission is to be downshifted, by determining whether or not an acceleration of the vehicle is equal to or greater than a downshift criterion value. The downshift criterion value is set as a value that decreases as the vehicle speed deviation, which is a difference between a vehicle speed and a target vehicle speed, increases. By using the downshift criterion value, an increase in the vehicle speed deviation resulting from a quick downshift on a steep downhill can be restrained. On a gentle downhill, a downshift is not performed even if the vehicle speed deviation assumes a significant value. Thus, it becomes possible to inhibit the vehicle speed from becoming lower than the target vehicle speed during a short period after downshift. Accordingly, an increase in fuel consumption and deterioration of noise of the engine can be restrained.
Abstract:
A method for controlling gear shifting of a transmission in a vehicle. The transmission is supplied with electric power from a battery or an alternator and drives an actuator to shift gear ranges of the transmission. The transmission has an output shaft that becomes difficult to rotate if a predetermined range is selected when the engine stops running. The method includes determining whether a gear range differing from the predetermined range is selected when the vehicle stops traveling, and forcibly shifts the gear range to the predetermined range when a gear range differing from the predetermined range is selected by driving the actuator with electric power supplied from the alternator.
Abstract:
The driving force control system calculates a target driving force Tt* and then calculates a target engine torque Te* from a target driving force Tt* and a target calculated engine torque gear ratio. When the transmission is not shifting, the driving force control system uses a gear ratio determined by the gear position as the target calculated engine torque gear ratio. When the transmission is shifting, the driving force control system uses an actual gear ratio calculated from the input and output rotational speeds. This gear ratio switching control makes it possible to vary the target engine torque Te* gradually in response to the change of the actual gear ratio during shifting. Thus, a dip in the output torque is eliminated, and the shifting shock is mitigated to a satisfactory level.
Abstract:
A multiple-gear vehicle transmission (3) has a split gear assembly (17) on its input side, a range gear assembly (19) on its output side, and a main gear assembly (18) between them. A drive power of an engine (1) is transmitted to a propeller shaft (5) via the multiple-gear vehicle transmission (3). The split gear assembly (17) has a neutral position (N) in addition to high and low gear positions (H, L). In general, a splitter controller (9, 20) intermittently shifts the split gear assembly (17) between the neutral position (N) and high gear position (H) to intermittently lubricate various parts such as bearings (61A, 61B, 61C) and synchronization mechanisms in a transmission casing (3a). By shifting the split gear assembly (17) into the high gear position, a counter shaft (32) is caused to rotate so that oil is scooped up toward the bearings by the counter shaft (32) and is also supplied to the bearings by an oil pump (35). However, when the engine (1) is started after a considerable period, the controller (9, 20) prohibits the split gear assembly (17) from being shifted into the neutral position (N) in order to continuously lubricate the bearings (61A, 61B, 61C) for a certain period. The intermittent lubrication is conducted after that.
Abstract:
A system for controlling an automatic transmission of a vehicle, wherein a pressure to be supplied to the hydraulic clutch of a target gear is determined based on a desired value of acceleration of gravity acting in the longitudinal direction of the vehicle and other parameters including an engine torque, thereby decreasing the shift shock effectively, while ensuring to finish the shift within an expected period of time. Moreover, the engine torque is estimated using a parameter indicative of inertia torque used for raising the engine speed. With this, it becomes possible to determine the engine torque inputted to the transmission, thereby decreasing the shift shock more effectively.