Abstract: An abnormal oil pressure reduction determining device has an oil pressure sensor which detects a real oil pressure, a sensor which detects a vehicle running state, and a controller which sets an oil pressure command value for an oil pressure control mechanism. The controller computes the lower limiting oil pressure which is possible in the present vehicle running state, and when the real oil pressure is less than this lower limiting oil pressure and the pressure difference between the real oil pressure and oil pressure command value exceeds a reference value, determines that there is an abnormal pressure reduction due to a fault in the oil pressure control mechanism. Even if the oil pressure of the transmission has dropped abnormally due to some reason, the abnormal oil pressure reduction determining device determines the situation without fail.

Abstract: A vehicle is provided with an engine (1), an automatic transmission (2) connected to the engine (1), a detection device (21–24, 31) which detects an operating state of the transmission (2), and a torque regulating mechanism (1a, 1b, 1c) which regulates a torque of the engine. When the operating state of the transmission (2) is in a predetermined drive state and the torque of the engine (1) is to be reduced, a selection is made, based on the operating state of the transmission (2), between a first torque reduction control whereby the torque of the engine (1) is reduced rapidly and temporarily, and a second torque reduction control whereby the torque of the engine (1) is reduced continuously, and more smoothly than in the first torque reduction control. The torque of the engine (1) is then reduced by the selected one of the first torque reduction control and the second torque reduction control.

Abstract: An abnormal oil pressure reduction determining device has an oil pressure sensor which detects a real oil pressure, a sensor which detects a vehicle running state, and a controller which sets an oil pressure command value for an oil pressure control mechanism. The controller computes the lower limiting oil pressure which is possible in the present vehicle running state, and when the real oil pressure is less than this lower limiting oil pressure and the pressure difference between the real oil pressure and oil pressure command value exceeds a reference value, determines that there is an abnormal pressure reduction due to a fault in the oil pressure control mechanism. Even if the oil pressure of the transmission has dropped abnormally due to some reason, the abnormal oil pressure reduction determining device determines the situation without fail.

Abstract: A shift control system for a V-belt type CVT is constructed to input a target torque signal obtained by estimating engine torque in accordance with vehicle operating conditions and a target shift ratio of the CVT, input an actual torque signal obtained by detecting actual engine torque, synthesize the target and actual torque signals to provide an estimated-torque signal, and control the line pressure in accordance with the estimated-torque signal.

Abstract: A vehicle is provided with an engine (1), an automatic transmission (2) connected to the engine (1), a detection device (21-24, 31) which detects an operating state of the transmission (2), and a torque regulating mechanism (1a, 1b, 1c) which regulates a torque of the engine. When the operating state of the transmission (2) is in a predetermined drive state and the torque of the engine (1) is to be reduced, a selection is made, based on the operating state of the transmission (2), between a first torque reduction control whereby the torque of the engine (1) is reduced rapidly and temporarily, and a second torque reduction control whereby the torque of the engine (1) is reduced continuously, and more smoothly than in the first torque reduction control. The torque of the engine (1) is then reduced by the selected one of the first torque reduction control and the second torque reduction control.