摘要:
A hydraulic control system for an automatic transmission comprising: a frictional engagement element (B-3); a hydraulic servo (28) for controlling the application/release of the frictional engagement element (B-3); an oil passage (201) connected to the hydraulic servo (28) for feeding/releasing an oil pressure to the hydraulic servo (28); a pressure regulator valve (25) disposed in the oil passage; and signal pressure generating means (SLU;...) for applying a signal pressure to the pressure regulator valve (25). The oil passage (201) includes: a first oil passage (201d) for feeding the oil pressure to the pressure regulator valve (25); and a second oil passage (201e) for feeding the oil pressure from the pressure regulator valve (25) to the hydraulic servo (28). The pressure regulator valve (25) includes: a valve member (250); an input port (254) connected to the first oil passage (201d); an output port (255) connected to the second oil passage (201e); and a drain port (257) connected to a drain oil passage (EX). The valve member (250) has: a first pressure receiving area (A₁) to be fed with the feedback pressure of the second oil passage (201e) in a direction to provide the communication between the output port (255) and the drain port (257); a second pressure receiving area (A₂) to be fed with the signal pressure (P SLU ) in a direction to provide the communication the output port (255) and the drain port (257); and a third pressure receiving area (A₃) having an area different from that of the second pressure receiving area (A₂). The signal pressure generating means (SLU;...) feeds the signal pressure to the third pressure receiving area (A₃) at all times and the signal pressure (P SLU ) selectively to the second pressure receiving area (A₂).
摘要:
An oil pressure controller of an automatic transmission which is capable of supplying engaging pressures to hydraulic servos of two frictional engaging elements which require different engaging pressures by a single pressure governing valve with a good pressure governing accuracy. The oil pressure controller comprises a hydraulic power source 10, hydraulic servos 70 and 80, signal pressure generating means 20, a pressure governing valve 30 for governing an oil pressure (P s ) from the hydraulic power source 10 by a signal pressure (P ACC ) and a control valve 40. The pressure governing valve 30 has a pressure receiving face A₁ to which the signal pressure is applied, a pressure receiving face A₂ to which the engaging pressure (P s ) is fed back in the opposite direction and a pressure receiving face A₃ for selecting whether the feedback of the engaging pressure is present or not in order to change the control gain of the pressure governing valve 30 in response to the change of the control valve 40 for selecting the hydraulic servo 70 or 80 to which the oil pressure is supplied.
摘要:
A control system for an automatic transmission comprising: a first frictional engagement element (B-3) and a second frictional engagement element (B-2); a first hydraulic servo (28) for controlling the application/release of the first frictional engagement element (B-3) and a second hydraulic servo (29) for controlling the application/release of the second frictional engagement element (B-2); an oil passage (203) connected to the first hydraulic servo (28) for feeding/releasing an oil pressure to/from the first hydraulic servo (B-3); a regulator valve (25) disposed in the oil passage (203) for regulating the oil pressure in the oil passage (203); and signal pressure generating means (SLU) for applying a signal pressure to the regulator valve (25), whereby a predetermined gear stage is established by changing the grips of the first frictional engagement element (B-3) and the second frictional engagement element (B-2) by feeding/releasing the oil pressure to/from the first hydraulic servo (28) and the second hydraulic servo (29). The regulator valve (25) includes a valve member (250) having: a first pressure receiving area (A 3 ) to which is applied (256) a feed pressure to the first hydraulic servo (B-3) as a feedback pressure in a first direction; a second pressure receiving area (A 4 ) to which is applied the signal pressure (P SLU ) in a second direction opposite to the first direction; a fourth pressure receiving area (A 1 ) to which is applied a feed pressure to the second hydraulic servo (29) in the first direction at a grip-change shifting time when the first frictional engagement element (B-3) is released whereas the second frictional engagement element (B-2) is applied; and a third pressure receiving area (A 2 ) to which is applied the signal pressure in the second direction, for participating in the regulation of the oil pressure in the first oil passage only at the shifting time.
摘要:
A method is provided for the control of servo hydraulic pressure in an automatic transmission. Servo hydraulic pressure is adapted to engage or release first and second frictional engagement elements arranged in such a relationship that upon shifting from a particular speed stage to another, one of the first and second frictional engagement elements is released while the other is engaged. The servo hydraulic pressure is linearly lowered in a torque phase during a shift so that the servo hydraulic pressure on a side of the frictional engagement element to be released by using as an input the servo hydraulic pressure on a side of the frictional engagement element to be engaged is maintained in conformity with an inversely proportional relationship between engaging pressure and drain pressure.
摘要:
An oil pressure controller of an automatic transmission which is capable of supplying engaging pressures to hydraulic servos of two frictional engaging elements which require different engaging pressures by a single pressure governing valve with a good pressure governing accuracy. The oil pressure controller comprises a hydraulic power source 10, hydraulic servos 70 and 80, signal pressure generating means 20, a pressure governing valve 30 for governing an oil pressure (P s ) from the hydraulic power source 10 by a signal pressure (P ACC ) and a control valve 40. The pressure governing valve 30 has a pressure receiving face A₁ to which the signal pressure is applied, a pressure receiving face A₂ to which the engaging pressure (P s ) is fed back in the opposite direction and a pressure receiving face A₃ for selecting whether the feedback of the engaging pressure is present or not in order to change the control gain of the pressure governing valve 30 in response to the change of the control valve 40 for selecting the hydraulic servo 70 or 80 to which the oil pressure is supplied.
摘要:
A hydraulic control system for an automatic transmission comprising: a frictional engagement element (B-3); a hydraulic servo (28) for controlling the application/release of the frictional engagement element (B-3); an oil passage (201) connected to the hydraulic servo (28) for feeding/releasing an oil pressure to the hydraulic servo (28); a pressure regulator valve (25) disposed in the oil passage; and signal pressure generating means (SLU;...) for applying a signal pressure to the pressure regulator valve (25). The oil passage (201) includes: a first oil passage (201d) for feeding the oil pressure to the pressure regulator valve (25); and a second oil passage (201e) for feeding the oil pressure from the pressure regulator valve (25) to the hydraulic servo (28). The pressure regulator valve (25) includes: a valve member (250); an input port (254) connected to the first oil passage (201d); an output port (255) connected to the second oil passage (201e); and a drain port (257) connected to a drain oil passage (EX). The valve member (250) has: a first pressure receiving area (A₁) to be fed with the feedback pressure of the second oil passage (201e) in a direction to provide the communication between the output port (255) and the drain port (257); a second pressure receiving area (A₂) to be fed with the signal pressure (P SLU ) in a direction to provide the communication the output port (255) and the drain port (257); and a third pressure receiving area (A₃) having an area different from that of the second pressure receiving area (A₂). The signal pressure generating means (SLU;...) feeds the signal pressure to the third pressure receiving area (A₃) at all times and the signal pressure (P SLU ) selectively to the second pressure receiving area (A₂).
摘要:
If oil temperature is equal to or higher than a predetermined temperature and if accelerator opening change rate is equal to or higher than a predetermined change rate upon detection of a downshift instruction (YES in S302), an ECT-ECU sets modes corresponding to conditions for determination period calculation processings (S400), hydraulic-pressure temporal change rate calculation processings (S500), and torque adjustment amount calculation processings (S600), respectively. By performing downshift (S310) on the basis of a determination period, a hydraulic-pressure temporal change rate, and a torque adjustment amount corresponding to a set mode, the ECT-ECU improves gear-shift responsive characteristics and restrains the occurrence of a gear-shift shock.
摘要:
A control system for an automatic transmission comprising: a first frictional engagement element (B-3) and a second frictional engagement element (B-2); a first hydraulic servo (28) for controlling the application/release of the first frictional engagement element (B-3) and a second hydraulic servo (29) for controlling the application/release of the second frictional engagement element (B-2); an oil passage (203) connected to the first hydraulic servo (28) for feeding/releasing an oil pressure to/from the first hydraulic servo (B-3); a regulator valve (25) disposed in the oil passage (203) for regulating the oil pressure in the oil passage (203); and signal pressure generating means (SLU) for applying a signal pressure to the regulator valve (25), whereby a predetermined gear stage is established by changing the grips of the first frictional engagement element (B-3) and the second frictional engagement element (B-2) by feeding/releasing the oil pressure to/from the first hydraulic servo (28) and the second hydraulic servo (29). The regulator valve (25) includes a valve member (250) having: a first pressure receiving area (A 3 ) to which is applied (256) a feed pressure to the first hydraulic servo (B-3) as a feedback pressure in a first direction; a second pressure receiving area (A 4 ) to which is applied the signal pressure (P SLU ) in a second direction opposite to the first direction; a fourth pressure receiving area (A 1 ) to which is applied a feed pressure to the second hydraulic servo (29) in the first direction at a grip-change shifting time when the first frictional engagement element (B-3) is released whereas the second frictional engagement element (B-2) is applied; and a third pressure receiving area (A 2 ) to which is applied the signal pressure in the second direction, for participating in the regulation of the oil pressure in the first oil passage only at the shifting time.