摘要:
A rotation clutch device rotates on an axis of an automatic transmission. The rotation clutch device comprises a clutch piston which slides around the axis of the automatic transmission for the engagement of the clutch device. First and second chamber are formed to slide the clutch piston in the direction of the engagement by receiving hydraulic pressure respectively. A cancel chamber is formed opposite to the first and second chambers through the clutch piston to cancel the centrifugal pressure generated in the first and second chambers. A selector valve selectively supplies hydraulic pressure to the first and second chambers according to a selected shift position of the automatic transmission to adapt to a different required engagement capacity in each shift position.
摘要:
In apparatus and method for controlling a gear shift of a vehicular automatic transmission, the automatic transmission the automatic transmission having a releasing frictional element, a clutching frictional element, and a source of a releasing working liquid pressure to be applied to the releasing frictional element and a clutching working liquid pressure to be applied to the clutching frictional element, a gear shift in the automatic transmission being carried out by a shift from the releasing frictional element to the clutching frictional element, during a time duration from a time at which a gear shift instruction is outputted to a time at which a torque phase is started, the releasing working liquid pressure is reduced and reached without undershooting to a first predetermined working liquid pressure value under which the releasing frictional element is in a state immediately before an occurrence of a slip and the clutching working liquid pressure is set at least a second predetermined working liquid pressure value under which the clutching element is in a state immediately before a clutching.
摘要:
An anti-creep control apparatus has a forward clutch control section that controls the hydraulic pressure of a forward clutch so as to slip the forward clutch when an automatic transmission is set in a drive range and the vehicle is stopped. The anti-creep control apparatus sets a target engagement time that is inversely proportional to the engine rotation speed at the time just before starting anti-creep control. The anti-creep control apparatus controls an oil pressure modulator so that one of a slip amount of the forward clutch and the output shaft rotation speed of the torque converter becomes nearly zero when the target engagement time elapses.
摘要:
A shift control apparatus of an automatic transmission executes a transient control of an engagement pressure of a first speed selecting friction element when a first speed is selected after a higher speed is once selected during a change from a neutral range to a forward drive range. A band brake pressure for selecting the second speed is rapidly increased at a first moment. A forward clutch pressure for selecting the first speed is increased at a second moment delaying to the first moment by a predetermined period adjusted to a line pressure lowered period. The forward clutch pressure is pre-charged during a period between the first and second moments, then being hold for a preset time period at a return spring corresponding pressure adjusted by a leaning control, and being increased by a slope adjusted by the leaning control for a predetermined period to establish the second speed by the engagement of the forward clutch. Then, the band brake pressure is rapidly decreased and further decreased by a slope to disengage the band brake in order to establish the first speed.
摘要:
An anti-creep control apparatus of an automatic transmission has a forward clutch control section which controls the hydraulic pressure of a forward clutch by slipping the forward clutch when the automatic transmission is set in a drive range and the vehicle is stopped while an engine is operating. The anti-creep control apparatus controls an hydraulic pressure of the forward clutch to be held or increased by a predetermined value when a relative rotation of the forward clutch is detected during the anti-creep control. The controlled hydraulic pressure is set as a lower limit value of the forward clutch hydraulic pressure in a present anti-creep control.
摘要:
An automatic transmission with an anti-creep control apparatus includes a torque converter connected to the engine, first and second friction elements, and a control unit. The first friction element is operated when the automatic transmission is put in a drive range. The second friction element performs to prevent a reverse rotation of an output shaft of the automatic transmission. The control unit executes an anti-creep control controls, controlling the second friction element to prevent a reverse rotation of an output shaft of the automatic transmission when the anti-creep control is executed, holds the engagement of the second friction element during a time period from the time when the anti-creep control is cancelled to the time when the first friction element is fully engaged, and disengages the second friction element thereafter.
摘要:
A toroidal continuously variable transmission (1) comprises power rollers (18C, 18D, 20C, 20D) which transmit a torque between input disks (18A, 20A) and output disks (20A, 20B), and trunnions (104, 105, 114, 115) which drive the power rollers (18C, 18D, 20C, 20D) in a perpendicular direction to a rotation shaft (16A) according to a differential pressure between a first oil chamber (101) and a second oil chamber (102). When the second oil chamber (102) is at higher pressure than the first oil chamber (101), the toroidal continuously variable transmission (1) causes a downshift, and when the first oil chamber (101) is at higher pressure than the second oil chamber (102), the toroidal continuously variable transmission (1) causes an upshift. The first oil chamber (101) is connected to a first passage (176) and the second oil chamber (102) is connected to a second passage (177). A speed ratio control valve (70, 70A) controls a direction and a flowrate of the first passage (176) and the second passage (177). A pressure control valve (200, 210, 220, 40, 45, 41, 46) limits a maximum differential pressure of the first oil chamber (101) and the second oil chamber (102) when the transmission (1) causes a downshift to be less than a maximum differential pressure of the first oil chamber (101) and the second oil chamber (102) when the transmission (1) causes an upshift. This arrangement prevents a sharp downshift of the toroidal continuously variable transmission (1) due to a fault or incorrect operation.
摘要:
In an infinitely variable transmission, a continuously variable transmission (2) outputs the rotation of an input shaft (1) at an arbitrary speed ratio, and a fixed speed ratio transmission (3) outputs the rotation of the input shaft (1) at a fixed speed ratio. A planetary gear set (5) varies the rotation direction and speed of the output shaft (6) according to the difference of the output rotation speed of the fixed speed ratio transmission (2) and the output rotation speed of the continuously variable transmission (2). A sensor (81) which detects the rotation speed of the input shaft (1) and a sensor (82) which detects the output rotation speed of the continuously variable transmission (2) are provided, and a microprocessor (80) precisely calculates the rotation direction and rotation speed of the output shaft (6) from these rotation speeds.
摘要:
In a non-finite speed ratio transmission device using a toroidal continuously variable transmission (2), a hydraulic cylinder (30) for driving a power roller (20) via a trunnion (23), a shift control valve (46) for controlling a supply direction of oil to an oil chambers (30A, 30B) of the hydraulic cylinder (30), and a precess cam (35) which feeds back a displacement of the power roller (20) to the shift control valve (46) so as to shut-off the flow of oil to and from the oil chambers (30A, 30B), are provided. The shift control valve (46) comprises a drain port (46J) which can be connected to the oil chamber (30A) and a drain port (46I) which can be connected to the oil chamber (30B). By providing a positive torque control valve (40) which controls the oil pressure of the drain port (46I), and a negative torque control valve (45) which controls the oil pressure of the drain port (46J), the shift control valve (46) controls a differential pressure &Dgr;P of the oil chambers (30A, 30B) from 0 to a line pressure PL when the speed ratio ic of the toroidal continuously variable transmission (2) is maintained in the vicinity of a geared neutral position GNP.
摘要:
The same rotation torque is input to a continuously variable transmission of a vehicle which continuously varies a speed change ratio and a reduction gear unit. A planetary gear mechanism is provided comprising an output shaft which varies a rotation direction according to a relation between the output speed of the continuously variable transmission and the output speed of the reduction gear unit. The continuously variable transmission varies the speed change ratio according to an oil pressure balance between two oil chambers. A direction change-over valve selectively supplies a first oil pressure and a second oil pressure to these oil chambers, and a control valve controls a differential pressure of the first oil pressure and second oil pressure. The control range of the differential pressure controlled by the control valve is narrowed due to reversal of the oil pressure supply direction by the direction change-over valve according to whether the vehicle is moving forward or in reverse, and control precision is thereby improved.