Abstract: Engagement, disengagement, and slip of a lock-up clutch can be controlled using two valves that are a lock-up relay valve and a linear solenoid valve. A lock-up control valve employed in a conventional hydraulic control apparatus can be eliminated, which simplifies the configuration, and reduces the size of a hydraulic control apparatus for a torque converter with a lock-up clutch. When the lock-up clutch is engaged, hydraulic pressure output from the linear solenoid valve is supplied to a disengagement-side oil chamber of the torque converter, and a pressure difference between the engagement-side oil chamber and the disengagement-side oil chamber is applied to a spool valve element of the linear solenoid valve. Therefore, the spool valve element is driven such that an electromagnetic force applied from a linear solenoid becomes equal to the pressure difference.

Abstract: A hydraulic control system that includes a solenoid valve for supplying a prescribed fluid pressure; and a relay valve for selectively switching a destination of the prescribed fluid pressure between a first destination part and a second destination part. The relay valve has an input port supplied with a normally produced fluid pressure and an output port that selectively communicates with the input port. The hydraulic control system further includes a fluid pressure switch, provided in the output port of the relay valve, that is activated when the input port communicates with the output port to allow the normally produced fluid pressure to be supplied to the output port.

Abstract: A transmission case includes a power transmission mechanism; a first case body and an adapter portion. The adapter portion includes a boss portion through which the output shaft is inserted, a first concave portion provided on an outer peripheral side of the boss portion and open rearward in the shaft direction, which is on the power output side of the power transmission mechanism, and a second concave portion open outward in a radial direction of the boss portion with the second concave portion separated in the shaft direction from the first concave portion by a separating wall.

Abstract: A control apparatus for controlling a vehicle automatic transmission including (i) a first coupling device to be engaged for establishing an emergency gear position and (ii) a second coupling device to be released for establishing the emergency gear position. The control apparatus includes: (a) first and second controller valves for controlling the respective first and second coupling devices; and (b) a fail-safe valve having (b-1) a first output port connected to a drain port of the first controller valve, (b-2) a first input port to which a working fluid is input, (b-3) a first drain port for draining the working fluid, (b-4) a second output port connected to an input port of the second controller valve, (b-5) a second input port to which the working fluid is input, and (b-6) a second drain port for draining the working fluid.

Abstract: A hydraulic control apparatus for controlling a vehicular automatic transmission including hydraulically operated frictional coupling devices which are selectively engaged and released to selectively establish gear positions having respective different speed ratios, and linear solenoid valves operable to regulate fluid pressures of the respective frictional coupling devices, each linear solenoid valve including a spool and a solenoid and being operable between a pressure-regulating state in which the spool is movable to a position of equilibrium of forces for regulating an output fluid pressure according to an electromagnetic force produced by the solenoid, and a non-pressure-regulating state in which the spool is held at a stroke end thereof at which no output fluid pressure is generated from the linear solenoid valve, each linear solenoid valve in the pressure-regulating state being operable to regulate a fluid pressure of the corresponding frictional coupling device according to the electromagnetic force,

Abstract: A control apparatus for controlling a stepped automatic transmission of a vehicle having an output shaft and an input shaft which is to be connected to an engine of the vehicle through a clutch while a shifting action is being effected in the transmission. The control apparatus includes a torque vibration restrainer operable, upon completion of the shifting action in the transmission, to restrain a torque vibration which is generated in a power transmitting path of the vehicle. The torque vibration restrainer applies an inverted-phase torque vibration which is inverted in phase with respect to the generated torque vibration, to the power transmitting path, and/or place the clutch in its slipping state or released state, for restraining the generated torque vibration.

Abstract: A hydraulic control apparatus for use with a vehicle's automatic transmission, the apparatus including a fail-safe switch valve which has an escape-related output port connected to a drain port of a transmission-related solenoid valve corresponding to an escape-related frictional coupling device to establish an escape-related speed step, and additionally has an escape-related input port to which a hydraulic pressure is inputted, and a drain port from which a hydraulic fluid is drained, wherein the fail-safe switch valve is selectively switchable to a normal communication state thereof in which the escape-related output port and the drain port are communicated with each other and the escape-related input port is shut off, and to a fail-related communication state thereof in which the escape-related output port and the escape-related input port are communicated with each other, and the drain port is shut off, so that a hydraulic pressure is supplied from the escape-related output port of the fail-safe switch va

Abstract: A hydraulic control apparatus for an automatic transmission comprises a linear solenoid valve for outputting a control pressure, a primary regulator valve for regulating a line pressure in accordance with the control pressure, and a secondary regulator valve for regulating a secondary pressure in accordance with the control pressure, the secondary pressure being supplied to a lock-up clutch and a torque converter. A spool of the secondary regulator valve is formed to comprise a large diameter portion and a small diameter portion, thereby eliminating the need for components such as a sleeve, and the line pressure can be input into an oil chamber formed between the large diameter portion and small diameter portion.

Abstract: A hydraulic control apparatus, provided with a manual shift valve that outputs a forward range pressure and a reverse range pressure, and a linear solenoid valve that outputs an engagement pressure to the hydraulic servo that engages during reverse travel when energized, includes a fourth clutch relay valve that is interposed between the linear solenoid valve and the hydraulic servo. The fourth clutch relay valve communicates an engagement pressure of the linear solenoid valve to the hydraulic servo by locking in the normal position when a signal pressure of the solenoid valve is input, and communicates a reverse range pressure to the hydraulic servo by being switched to a fail position by the reverse range pressure during a failure in which the fourth clutch relay valve is de-energized. Thereby, it is possible to establish a reverse speed during a failure in which the solenoid valve is de-energized.

Abstract: A hydraulic control apparatus for an automatic transmission including two frictional coupling devices of a first group and a plurality of frictional coupling devices of a second group, the control device including a second-group-engaging switching valve arranged to receive second engaging hydraulic pressures generated to engage the coupling devices of the second group and operable, upon reception of at least one of the second engaging hydraulic pressures, to generate a second-group-engaging pilot hydraulic pressure, and a fail-safe valve to receive at least one of first engaging hydraulic pressures generated to engage the two coupling devices of the first group and operable, upon simultaneous reception of the first engaging hydraulic pressure generated to engage one of the two coupling devices of the first group and the second-group-engaging pilot hydraulic pressure, to prevent application of the first engaging hydraulic pressure to the other of the two coupling devices of the first group.

Abstract: A hydraulic control apparatus for an automatic transmission is provided with a solenoid valve that outputs a signal pressure during a failure and does not output a signal pressure during normal operation and a first clutch apply relay valve that switches between a normal position (the right half position) and a fail position (the left half position) based on this signal pressure are provided. During a failure, fail-safe control is carried out by the first clutch apply relay valve switching to the fail position. This first clutch apply relay valve inputs the engagement pressure of the hydraulic servo from the linear solenoid valve when in the normal position, and is locked in the normal position. Thereby, while the first clutch is engaged, the second brake apply control valve can be switched by the signal pressure of the solenoid valve.

Abstract: A hydraulic control apparatus for a multi-stage automatic transmission includes solenoid valves such as the linear solenoid valves that are formed as normally closed valves. A first clutch apply relay valves that outputs a forward range pressure as a reverse input pressure during an all-solenoid-off mode, and a second clutch apply relay valves that switches between a left half position that inputs a reverse input pressure to a discharge port and a right half position that inputs the reverse pressure to the discharge port are provided. The second clutch apply relay valve is set to the right half position during normal engine startup and locked based on the lock pressure by feeding the line pressure as a lock pressure and is set at the left half position that interrupts the lock pressure after the engine is restarted during all-solenoids-off.

Abstract: A hydraulic servo for a brake in an automatic transmission has a piston secured against rotation without provision of a protrusion on the piston engaging the transmission casing. The piston of the hydraulic servo has an inner cylindrical surface configured to grasp, along their lengths, return springs compressed between the piston and a return plate to which the return springs are fixed. The return plate is bolted to a bulkhead portion of the transmission case and, thus, the piston member is fixed to the bulkhead portion and thereby prevented from rotating.

Abstract: The present invention provides an automatic transmission having a main bearing disposed between the inner surface of a boss portion of a first drum and the outer surface of a cylindrical support, for rotatably supporting the first drum. An auxiliary bearing is press-fit into one end of the interior of the boss portion of the first drum and surrounds the cylindrical support with an annular gap therebetween. The auxiliary bearing contacts the cylindrical support only when the first drum tilts relative to the central axis of the transmission, and has a shorter axial length than that of the main bearing.

Abstract: A piston operating a first clutch is disposed between a first drum accommodating the first clutch and a second drum accommodating a second clutch, and an oil reservoir storing lubricating oil that has lubricated the first clutch is provided on an inner cylindrical surface of a skirt portion of the piston. Barriers having different inner diameters are provided to the axial front and rear of the oil reservoir. When the second clutch is disengaged such that the amount of lubricating oil supplied to the oil reservoir increases, the lubricating oil overflows the barrier having the smaller inner diameter, and thus flows to the second clutch.

Abstract: In a hydraulic servo for a clutch, a cancel plate is disposed on a second clutch drum that undergoes the same rotation as a second clutch drum provided with a cylinder portion, in such a fashion that the cancel plate is restricted from moving to a side opposite from a return spring in an axial direction. The first clutch drum is disposed, as a separate member, on the second clutch drum. A step portion of the second clutch drum prevents the first clutch drum from moving to a side opposite from the cancel plate. Due to the spring force of the return spring, the oil pressure in the cancel oil chamber and the oil pressure in the operating oil chamber, the force that presses the first clutch drum to the step portion is always greater than the force that presses the first clutch drum to the cancel plate side.

Abstract: An automatic transmission is capable of shifting between multiple speeds by engaging and disengaging multiple frictional engagement devices including at least one clutch and one brake, and is capable of switching between a driving range and a non-driving range with operation of a shift lever, wherein a first brake is engaged to fix an intermediate rotary member to a transmission case in a non-driving range such as neutral range. Thus, rotation of a clutch from drag torque can be stopped and shock due to engagement of a brake can be prevented by engagement of the first brake in the non-driving range.

Abstract: An automatic transmission supplies oil pressure to a hydraulic servo of a second clutch through an oil pressure supply passage extending through a first drum and a second drum, the oil pressure supply passage including a plurality of first oil holes formed in the first drum at equal, circumferential intervals, a plurality of second oil holes formed in the second drum at equal, circumferential intervals, and an annular oil passage formed between the first and second drums and connecting the first oil holes and the second oil holes. The number of first oil holes is different from the number of second oil holes.

Abstract: In a hydraulic servo for a clutch, a cancel plate is disposed on a second clutch drum that undergoes the same rotation as a second clutch drum provided with a cylinder portion, in such a fashion that the cancel plate is restricted from moving to a side opposite from a return spring in an axial direction. The first clutch drum is disposed, as a separate member, on the second clutch drum. A step portion of the second clutch drum prevents the first clutch drum from moving to a side opposite from the cancel plate. Due to the spring force of the return spring, the oil pressure in the cancel oil chamber and the oil pressure in the operating oil chamber, the force that presses the first clutch drum to the step portion is always greater than the force that presses the first clutch drum to the cancel plate side.

Abstract: In a hydraulic control apparatus for a vehicular automatic transmission, if it is determined that there is a failure that may cause tie-up in an automatic transmission, communication is provided between a first output port and a first drain port in a switching valve. As a result, a hydraulic frictional engagement device, which should be disengaged when there is a failure, is disengaged. Also, a specific shift speed is achieved by controlling the switching valve. Therefore, it is not necessary to select a shift speed that is achieved on the condition that the hydraulic frictional engagement device, which should be disengaged when there is a failure, is engaged. Thus, it is possible to prevent a shift that may impair driveability when there is a failure that may cause tie-up in the automatic transmission.