摘要:
In a shift control system for an automatic transmission, shelf-pressure control means include means for increasing the engagement pressure of the friction elements at a first gradient as previously set after output of the shift command, wherein after output of the shift command and when start of the inertia phase is detected, a torque-reduction command is output to the torque-reduction control means, the engagement pressure at detection of the inertia phase is set as an initial shelf pressure to increase the shelf pressure at a second gradient set for each speed, and a torque variation part oil pressure is added only when detecting a variation in throttle opening, and wherein after start of the inertia phase and when completion of the inertia phase is detected, a torque-reduction completion command is output to the torque-reduction control means.With this, the shelf pressure can be set appropriately during inertia phase without needing an enormous data amount even if a variation in throttle opening is present.
摘要:
There is provided a hydraulic control device for an automatic transmission, which is comprised of an engagement state determining section and a protection control section. If the engagement state determining section determines that each clutch, which is supplied with a line pressure via a regulating valve having a spool and has an oil pressure switch disposed in an oil channel, is held in an engaged state when gears are not changed, the protection control section sets a command pressure for the regulating valve to a protective oil pressure lower than the line pressure. This brings the regulating valve into a pressure-regulating state to cause lands of the spool to form apertures that reduce hydraulic vibration applied to the line pressure. This inhibits an oil pressure beyond an acceptable value from being applied to the oil pressure switch, and therefore improves the durability of the oil pressure switch.
摘要:
A shift control system of an automatic transmission executes an interchange shift by interchanging engagement conditions of first and second friction elements of the automatic transmission. The first and second friction elements are engaged and disengaged according to oil pressures supplied thereto. A controller of the shift control system is arranged to decrease the second oil pressure of the second friction element by a second predetermined gradient and to increase the first oil pressure of the first friction element by a first predetermined gradient after the loss stroke of the first friction element is terminated, and to determine the first gradient such that a difference between a command pressure and an actual pressure of the first friction element is kept substantially constant.
摘要:
A shift control apparatus is arranged to effect a shift in an automatic transmission by changeover of friction elements to be engaged with disengagement of a disengagement-side friction element and engagement of an engagement-side friction element. A shift controller is configured to detect an end of a loss stroke in the engagement-side friction element, and performs an operation to decrease the disengagement-side working oil pressure at a set gradient and to increase the engagement-side working oil pressure at a predetermined gradient upon detection of the end of the loss stroke in the engagement-side friction element. The predetermined gradient of the engagement-side working oil pressure for the engagement-side friction element is made lower for a low engine load than for a high engine load.
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:
A vibration damping equipment for a torsional damper comprises a hub plate, side plates, a torsion spring, a friction block, and low rigidity members. Each low rigidity member is interposed between the hub plate and each friction block to be adjacent to each other through a partition of the hub plate. The low rigidity members are connected to each other on at least one axial side of the partition.
摘要:
A lock-up control device in which a pulse train is generated which has a duration which increases as the vehicle speed decreases. A counter generates a period indicative signal indicative of a current period of the pulse train. A memory stores the period indicative signal for a preceding period. An adder generates an adder signal indicative of the addition of a preset value to the period indicative signal stored in the memory. A comparator compares the adder signal with the period indicative signal generated by the counter and generates a comparator signal when the former is larger than the latter. A flip-flop generates a flip-flop signal when the comparator signal occurs under the presence of a lock-up signal. An AND gate provides a lock-up release signal when said flip-flop signal occurs irrespective of the presence of the lock-up signal.
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 clutch-slip control arrangement for a lock-up torque converter includes an orifice which is variable in opening in response to relative rotation or relative axial movement of a turbine hub and an output hub. In accordance with the present invention, a friction member is interposed between the turbine hub and the output hub for changing a performance characteristic of the orifice in such a manner that an orifice opening characteristic is different from an orifice closing characteristic.
摘要:
A slip control mechanism comprises a throttling path with a cross-sectional area variable according to the relative displacement of an output element of a torque converter and an output shaft. The throttling path is in communication via a fluid passage with a disengagement chamber opposing one side of a friction clutch. The other side of the friction clutch faces an engagement chamber. The disengagement chamber and the engagement chambers are so arranged as to control slippage of the friction clutch by pressure balance therebetween. The throttling path is formed in a specific geometry which assures moderate changes in the pressure balance between the disengagement chamber and engagement chamber in an intermediate throttling range. In the preferred construction, the throttling path is so constructed that the rate of change of the throttling cross-sectional area satisifes the inequalityd.sup.2 S/dx.sup.2 .gtoreq.whereS is the cross-sectional area of the throttling path, andx is the relative displacement of the output element of the torque converter and the output shaft.