摘要:
A fluid coupling transmits power from a drive side to a driven side by utilizing kinetic energy of fluid such as oil. The fluid coupling comprises a pump impeller (4) provided on a drive shaft (1), a turbine impeller (5) provided on a driven shaft (9), a housing (20) fixed to the pump impeller (4) and surrounding the turbine impeller, and a multiple disc clutch provided between a drive shaft side and a driven shaft side. The multiple disc clutch is operated to couple the drive shaft (1) and the driven shaft (9) mechanically so that the drive shaft and the driven shaft are rotated at the same rotational speed. Thus, the fluid coupling can improve a power transmitting efficiency because of no slip between the rotational speed of the drive shaft and the rotational speed of the driven shaft.
摘要:
There is provided a hydraulic pressure control apparatus for a vehicular hydraulic power transmission device with a lock-up clutch, in which an increase in the temperature of hydraulic oil in an engagement side oil chamber is suppressed, durability of frictional material is improved, and the lock-up clutch is appropriately controlled. A switching control valve (a lock-up relay valve 250 and a lock-up control valve 252) switches between connection and disconnection between each of two oil passages that communicate with an engagement side oil chamber 31, and each of a high pressure oil passage and a low pressure oil passage, according to the operating state of the lock-up clutch 11. For example, when the lock-up clutch is completely engaged, the hydraulic oil is supplied to both the two oil passages from the high pressure oil passage, hydraulic pressure PON in the engagement side oil chamber 31 is increased, and a sufficient transmission torque capacity of the lock-up clutch 11 is obtained. When the lock-up clutch 11 is in the slip state, one of the two oil passages is connected to the high pressure oil passage, and the other oil passage is connected to the low pressure oil passage such that the hydraulic oil is circulated in the engagement side oil chamber 31. Therefore, an increase in the temperature of the hydraulic oil is suppressed, the lock-up clutch 11 is cooled, and the durability of the frictional material 36 is improved.
摘要:
To control one clutch (2) in a hydrodynamic torque converter, the pressure acting upon one first piston area (4) is supplied to a control unit which, depending on the pressure, adjusts the pressure acting upon a second piston area (5). It is possible to exactly adjust the piston force acting upon a clutch (2) even in the presence of changing pressure ratios within the hydrodynamic torque converter.
摘要:
A lock-up control apparatus for an automatic transmission in which operations of four engagement elements are required when shifting is performed from a first shift speed to a second shift speed, the first shift speed being achieved by engagement of a first engagement element and a second engagement element, the second shift speed being achieved by engagement of a third engagement element and a fourth engagement element. The lock-up control apparatus includes a lock-up control unit that performs a control for bringing a lock-up clutch into one of a disengagement state and a slip state at a start of shifting, and that prevents reengagement of the lock-up clutch at a completion of engagement of the third engagement element when shifting is performed from the first shift speed to the second shift speed during lock up.
摘要:
A lock-up control system for a torque converter which includes a lock-up clutch engageable under control of an engaging capacity of the lock-up clutch to thereby lock up input and output elements of the torque converter. The control system is operative during coasting in a lock-up region requiring engagement of the lock-up clutch, so as to bring the engaging capacity of the lock-up clutch to a coast lockup capacity smaller than a lock-up capacity under a driving condition at the same vehicle speed. The control system is further operative when an engine braking range is selected during coasting in the lock-up region, so as to bring the engaging capacity of the lock-up clutch to a value greater than the coast lock-up capacity, preferably to a controlling maximum value.
摘要:
In an apparatus for controlling an automatic transmission which is provided with a torque converter having a fluid coupling unit for coupling driving force to a transmission through fluid coupling and a direct coupling unit for coupling the driving force to the transmission through mechanical coupling and being operative to take a fluid coupling state, a direct coupling state or an intermediate state between the fluid and direct coupling states in accordance with a working pressure applied to the direct coupling unit, a control signal is generated for changing the initial value of the working pressure in accordance with the driving force during the period of transition between the fluid coupling state and the direct coupling state.
摘要:
A clutch control device of a continuously variable transmission is provided with a clutch control part, which controls the engagement state of a clutch. The minimum engaging force, which is capable of maintaining the completely engaged state of the clutch, is predetermined to increase according to an increase in engine torque. The clutch control unit has an engaging force setting part, which sets the target engaging force for the clutch to a higher value than the minimum engaging force by a predetermined value. The clutch control unit controls the engagement state of the clutch so that the actual engaging force for the clutch can be higher than the minimum engaging force by the predetermined value. Therefore, the clutch control device can improve the fuel economy and prevent a shift shock when there is a rapid increase in the engine torque.
摘要:
A torque converter clutch control valve has a single valve element for controlling the fluid distribution to and from a torque converter and clutch assembly to establish clutch engagement and disengagement as well as torque converter operation. The control valve has one position for supplying fluid to release the clutch and simultaneously feed the torque converter, and another position to supply a pressure controlled fluid to engage the clutch. A force motor control valve is provided to control the pressure level of the clutch engagement pressure.
摘要:
In a lockup control system of an automatic transmission with a lockup torque converter, a controller pre-stores a predetermined lockup control map including at least a predetermined coast slip lockup area, within which the system executes a slip lockup control mode under the vehicle's coasting condition, so that a speed difference between input and output speeds of the torque converter is brought closer to a predetermined value. The controller determines whether a first transition from the vehicle's driving condition to the predetermined coast slip lockup area occurs in a release mode of the lockup clutch or a second transition from the vehicle's coasting condition to the predetermined coast slip lockup area occurs in the release mode. When the first transition occurs, the lockup clutch is conditioned in the slip lockup control mode. When the second transition occurs, the lockup clutch is conditioned in the release mode.
摘要:
A vehicular lockup clutch-equipped transmission control apparatus is applied to a vehicle that includes a heater apparatus for heating a cabin by heat from an engine, a transmission that transfers power between the engine and a wheel, and a heat exchanger that conducts heat exchange between the engine and the transmission. The control apparatus controls a lockup clutch that is disposed between the engine and the transmission and that mechanically connects and disconnects a path of power, in accordance with a state of operation of the vehicle. The control apparatus includes a controller that determines whether a heating capability requested of the heater apparatus is at least a first predetermined level based on a parameter related to a temperature inside the cabin. If it is determined that the heating capability requested of the heater apparatus is at least the first predetermined level, the controller restricts engagement of the lockup clutch.