摘要:
In one embodiment, an oil pressure control apparatus includes a belt-driven continuously variable transmission, a lockup clutch provided in a torque converter, a primary regulator valve that regulates a line oil pressure that becomes a source pressure of oil pressure of various parts, and a lockup control valve that performs switching when controlling engagement/release of the lockup clutch. Control of the primary regulator valve and control of the lockup control valve are performed with a single linear solenoid valve. In this case, control of the primary regulator valve and control of the lockup control valve are performed in different ranges.
摘要:
In one embodiment, an oil pressure control apparatus includes a belt-driven continuously variable transmission, a lockup clutch provided in a torque converter, a primary regulator valve that regulates a line oil pressure that becomes a source pressure of oil pressure of various parts, and a lockup control valve that performs switching when controlling engagement/release of the lockup clutch. Control of the primary regulator valve and control of the lockup control valve are performed with a single linear solenoid valve. In this case, control of the primary regulator valve and control of the lockup control valve are performed in different ranges.
摘要:
A hydraulic control system for a vehicular drive system including a hydraulically operated belt-and-pulley type continuously variable transmission and a hydraulically operated frictional coupling device engaged for running of a vehicle, the hydraulic control system including: a first solenoid valve for regulating a belt-tensioning hydraulic pressure for tensioning a belt of the transmission, a second solenoid valve for regulating a transient coupling hydraulic pressure to be applied to the frictional coupling device in the process of an engaging action, a line-pressure regulating valve for regulating a line pressure used for hydraulically operated devices of the mechanism, and a hydraulic-circuit switching device operable to apply a control pressure of the second solenoid-operated valve to the line-pressure regulating valve after the frictional coupling device has been placed in a fully engaged state, and to apply a first control pressure of the first solenoid-operated valve to the line-pressure regulating valve while the frictional coupling device is in the process of the engaging action.
摘要:
In a vehicular belt-driven continuously variable transmission, belt squeezing force is inhibited from becoming excessive and a safety factor, with respect to belt slip, of belt squeezing force applied to a transmission belt (48) is reduced to a value that is less than or equal to 1.5 by reducing a pressure receiving area (SOUT) of an output side hydraulic cylinder (46c). As a result, a centrifugal hydraulic pressure canceller chamber on a secondary pulley side (46) can be eliminated thus simplifying the structure of the vehicular belt-driven continuously variable transmission, while belt squeezing force can be appropriately controlled.
摘要:
A hydraulic control system for a vehicular drive system including a hydraulically operated belt-and-pulley type continuously variable transmission and a hydraulically operated frictional coupling device engaged for running of a vehicle, the hydraulic control system including: a first solenoid valve for regulating a belt-tensioning hydraulic pressure for tensioning a belt of the transmission, a second solenoid valve for regulating a transient coupling hydraulic pressure to be applied to the frictional coupling device in the process of an engaging action, a line-pressure regulating valve for regulating a line pressure used for hydraulically operated devices of the mechanism, and a hydraulic-circuit switching device operable to apply a control pressure of the second solenoid-operated valve to the line-pressure regulating valve after the frictional coupling device has been placed in a fully engaged state, and to apply a first control pressure of the first solenoid-operated valve to the line-pressure regulating valve while the frictional coupling device is in the process of the engaging action.
摘要:
In a vehicular belt-driven continuously variable transmission, belt squeezing force is inhibited from becoming excessive and a safety factor, with respect to belt slip, of belt squeezing force applied to a transmission belt (48) is reduced to a value that is less than or equal to 1.5 by reducing a pressure receiving area (SOUT) of an output side hydraulic cylinder (46c). As a result, a centrifugal hydraulic pressure canceller chamber on a secondary pulley side (46) can be eliminated thus simplifying the structure of the vehicular belt-driven continuously variable transmission, while belt squeezing force can be appropriately controlled.
摘要:
In a hydraulic control system for a transmission, line pressure Pl is adjusted in accordance with a second solenoid pressure Psls if the ratio of a first sheave pressure Pin with respect to a second solenoid pressure Psls is equal to or less than the gain α. If not so, the line pressure Pl is adjusted in accordance with the first sheave pressure Pin. Consequently, the gain η of the first sheave pressure Pin with respect to a first solenoid pressure Pslp at a first sheave pressure adjustment valve 16 and the gain α of a second sheave pressure Pout with respect to the second solenoid pressure Psls at a second sheave pressure adjustment valve 17 can be individually set while the line pressure Pl can be suppressed to the substantially requisite minimum in the entire control region.
摘要:
In a hydraulic control system for a transmission, line pressure Pl is adjusted in accordance with a second solenoid pressure Psls if the ratio of a first sheave pressure Pin with respect to a second solenoid pressure Psls is equal to or less than the gain α. If not so, the line pressure Pl is adjusted in accordance with the first sheave pressure Pin. Consequently, the gain η of the first sheave pressure Pin with respect to a first solenoid pressure Pslp at a first sheave pressure adjustment valve 16 and the gain α of a second sheave pressure Pout with respect to the second solenoid pressure Psls at a second sheave pressure adjustment valve 17 can be individually set while the line pressure Pl can be suppressed to the substantially requisite minimum in the entire control region.
摘要:
In an oil pressure control device equipped with a plurality of solenoid valves, and foreign matter discharge means, the foreign matter discharge means carries out the foreign matter discharge treatment for a treatment period composed of a first period T1 in which a current smaller than a predetermined value is supplied to one of the solenoid valves and a second period T2 in which a current equal to or larger than the predetermined value is supplied to the one of the solenoid valves, and the foreign matter discharge means makes timings for varying the current values different from one another so as to start supplying a current equal to or larger than the predetermined current value to another at the beginning of the first period T1, and start supplying a current smaller than the predetermined value to the another one at the beginning of the second period T2.
摘要:
A hydraulic control circuit that shuts off an oil passageway so that the ratio between the shift pressure and the belt clamping pressure is not caused to be in a predetermined relationship even when a speed change ratio control valve and/or a speed change ratio control valve are not supplying/discharging hydraulic oil. Therefore, even if the speed change ratio control valve and/or the speed change ratio control valve cease supplying/discharging the hydraulic oil, the action of a thrust ratio control oil pressure Pτ output from a thrust ratio control valve on a primary hydraulic cylinder is avoided. Thus, impairment of the continuity of control at the time of a shift of the continuously variable transmission is prevented.