Abstract: A solenoid valve (10) has a valve housing (11); one end portion of the valve housing (11) is provided with a flow passage portion (16) having ports and a valve element housing hole to store a poppet valve (41), and the other end portion of the valve housing (11) is opened. Parts, such as a fixed iron core (50) having a supporting leg (52) and a driving leg (51), and a movable iron core (60) which drives the poppet valve (41) is inserted from an opening end (17) on the other end portion of the valve housing (11). All parts to be inserted into the valve housing (11) are inserted from one direction.

Abstract: A method is described for determining a reference value of an actuating current that corresponds to a defined operating point of an electro-hydraulically actuated frictional shifting element of a continuously variable power-branched transmission, at which the shifting element transmission capacity is zero, and starting from which an increase of actuating force immediately increases the transmission capacity. The actuating current reference value of the shifting element, when closed with a further shifting element decoupled from the transmission output and when a transmission input rotational speed is higher than a defined threshold, is reduced until a rotational speed difference between the rotational speeds of the shifting element halves exceeds a predefined limit value such that, at the time when the limit value is exceeded, the reference value of the actuating current is the reference value of the actuating current that corresponds to the defined operating point of the shifting element.

Abstract: A control device for a vehicular lockup clutch, including a lockup clutch that directly connects an input rotation member and an output rotation member of a hydraulic transmission device constituting part of a power transmission path between an engine and drive wheels, a linear solenoid valve that controls an engagement hydraulic pressure for engaging and actuating the lockup clutch, and a controller that is configured to perform a flexible start control for slip-engaging the lockup clutch when a vehicle starts moving, and to perform, before starting the flexible start control, a precharge control for establishing a standby state in which a predetermined preparation pressure is indicated to the linear solenoid valve.

Abstract: A fluid pressure control device for an automatic transmission that transfers power from a motor via a friction engagement element, including: a first pump actuated by the power from the motor; a pressure regulator that regulates pressure of a working fluid pumped from the first pump; a first flow passage connected to an output port of the pressure regulator; a second flow passage connected to a fluid pressure chamber of the friction engagement element; a switcher that establishes and blocks connection between the first flow passage and the second flow passage; a second pump actuated by supply of electric power and capable of supplying the working fluid to the second flow passage with connection between the first flow passage and the second flow passage blocked by the switcher; and a pressure accumulator that accumulates pressure of the working fluid. The pressure accumulator is connected to the first flow passage.

Abstract: Features for varying speeds available and/or range of operation of transmissions are provided for use in high performance, increased efficiency, and/or other applications. Increased performance and/or efficiency may be obtained by using additional speeds or gear ranges to maintain drivetrain operation within maximum power and/or efficiency bands of internal combustion engine operation.

Abstract: A solenoid valve apparatus includes a solenoid valve and a switching device that switches between a first state in which the working fluid in the pump chamber is discharged when the solenoid valve functions as a regulator valve and a second state in which discharge of the working fluid from the pump chamber is prohibited when the solenoid valve functions as the electromagnetic pump.

Abstract: A drive unit that includes a solenoid device that includes: a solenoid section having a movable portion that abuts on a case to arrive at an initial state when de-energized; a pump section axially sliding in association with a movement of the movable portion by an electromagnetic force of the solenoid section and pumping a hydraulic fluid by reciprocation; and an elastic member biasing the pump section in a direction counter to the electromagnetic force of the solenoid section; and a control unit that controls the solenoid device so that a current applied to the solenoid section is repeatedly increased and decreased between an upper limit value and a lower limit value that is greater than 0.

Abstract: A hydraulic control device for a multi-speed automatic transmission includes friction engagement elements, several hydraulic servos that engage and release the friction engagement elements, solenoid valves for engagement control, and a sorting switch valve that allocates engagement pressure from at least one of the solenoid valves for engagement control to two of the hydraulic servos. The sorting switch is switched between a first position that supplies engagement pressure to one of the two hydraulic servos in at least a Reverse, non-drive range and a specific Forward gear range, and a second position that supplies engagement pressure to the two hydraulic servos in other than the Forward range.

Abstract: A hydraulic control system for a automatic transmission includes a plurality of solenoids and valves in fluid communication with a plurality of shift actuators. The shift actuators are operable to actuate a plurality of torque transmitting devices. Selective activation of combinations of the solenoids allows for a pressurized fluid to activate at least one of the shift actuators. The solenoids are configured to provide a forward gear ratio and a reverse gear ratio when the solenoids are deengerized.

Abstract: A pressure (p_3) setting system (200) with a pressure control valve (1), comprising a valve gate (10) arranged to be displace in a valve bore (12). The valve bore has at least one pressure chamber (21, 22, 23, 24, 25, 26), in which the valve gate may be axially exposed to a pressure. A first pressure chamber (21) is connected to at least one acceleration-dependent compensation member (203) for full or partial compensation of any pressure (p_3) setting disturbances caused by mass forces (F_a1, F_a2) resulting from the acceleration (a) of the system.

Abstract: The present invention provides a system for shifting or controlling a dual clutch transmission where the transmission may operate in at least a first mode of operation and a second mode of operation. The system includes a controller and a plurality of solenoids in fluid communication with a valve assembly. Selective activation of the solenoids by the controller engages the valve assembly to provide the first mode and the second mode of operation.

Abstract: In a vehicle powertrain that continually transmits power to a first set of vehicle wheels and selectively transmits power through a clutch to a second set of vehicle wheels, a method for controlling the clutch includes determining that brakes for slowing the vehicle wheels are applied and that an accelerator pedal of the vehicle is depressed less than a reference magnitude, determining that the rate of change of the average front wheel speed is greater than the rate of change of the average rear wheel speed, and setting the torque capacity of the clutch to a target magnitude.

Abstract: A shift control method of an automatic transmission that controls a shift from an nth shift speed, achieved by engagement of first and second friction elements, to an (n?3)th shift speed, achieved by engagement of third and fourth friction elements. The method includes releasing the first and second friction elements and engaging the third and fourth friction elements. Release control of the second friction element begins after release control of the first friction element begins. Engagement control of the fourth friction element begins after an engagement control of the third friction element begins.

Abstract: Method of operating a drivetrain, comprising at least an automatic transmission and a drive motor, for improving a speed of successive upshifts or successive downshifts in an overlap manner so that, during a first upshift or downshift, at least one shift element, required for a subsequent second upshift or downshift, is prepared during the first upshift or downshift and, when a synchronization point is reached, the subsequent second upshift or downshift can be carried out immediately. Two successive respective upshifts or downshifts can be carried out as an overlapping single shift by actuating first, second and third shift elements. Implementing the first and the second upshifts or downshifts so that actuation of the second shift element, from the first upshift or downshift to the subsequent second upshift or downshift, occurs via a minimum selection of a first alternative or by a maximum selection of a second alternative.

Abstract: A maximum flow calculating unit calculates a maximum amount of hydraulic fluid that can flow into or out of an input-side hydraulic cylinder when a shift control command signal is set to a reference DUTY value, based on an estimated valve pressure difference calculated by an estimated pressure difference calculating unit, and a post-guard target sheave position setting unit performs a guard process for restricting the amount of change of the sheave position, using a guard value calculated by a guard value calculating unit based on the maximum flow amount, so as to set a post-guard target sheave position. Since the thus set target sheave position does not undergo excessive large changes nor excessively small changes during shifting, a target value for shifting is set so that a feedforward controlled variable determined based on the amount of change of the target sheave position becomes an appropriate value.

Abstract: A system for controlling a shifting during shifting, in which a frictional element is re-engaged in mid-course of being released, includes: one or more detectors for detecting driving information of a vehicle and generating one or more signals corresponding thereto; a transmission control unit for receiving the signals from the detectors and generating a control signal; and an actuator for receiving the control signal and generating a control pressure for controlling a transmission. The transmission control unit performs a control method of the shifting during shifting. The method includes: detecting driving information of a vehicle; determining whether the shifting during shifting is occurring; if the shifting during shifting is occurring, maintaining a control pressure at a stand-by pressure; determining whether an engaging condition of the frictional element is satisfied; and increasing the control pressure of the frictional element.

Abstract: A hydraulic circuit control device that selectively supplies oil to a first oil passage and a second oil passage by an oil pump, the control device includes: an oil passage switching unit adapted to connect the oil pump to either the first oil passage or the second oil passage; a control mode switching unit adapted to switch the control mode of the electric motor to either a torque control mode or a speed control mode; an oil passage selecting unit adapted to select whether to connect the oil pump to the first oil passage or the second oil passage; and a control unit adapted to perform control so that the control mode switching unit switches the control mode to the torque control mode when the first oil passage has been selected, and perform control so that the control mode switching unit switches the control mode to the speed control mode when the second oil passage has been selected.

Abstract: A method and apparatus to monitor operation of an electrically-actuated hydraulic pump selectively operative to supply pressurized fluid to a hydraulic circuit for a transmission device operably connected to an internal combustion engine of a vehicle includes monitoring vehicle operation and passively and intrusively monitoring hydraulic circuit pressure. The hydraulic pump is functioning properly when the monitored pressure in the hydraulic circuit exceeds a threshold. A fault related to the hydraulic circuit is identified when the monitored pressure in the hydraulic circuit does not exceed the threshold.

Abstract: There is provided a shift control device for an automated manual transmission having power transmission lines equipped with respective start clutches and gears. The shift control device includes clutch actuation mechanisms and a transmission shift controller that causes the clutch actuation mechanisms to regulate the clutch engagement forces applied to the start clutches so as to perform clutch changeover upon gear selection for a desired gear range in response to a transmission shift command. Each of the clutch actuation mechanisms has primary and secondary clutch engagement force regulation units.

Abstract: A hydraulic control apparatus and method of controlling it for an automatic dual clutch transmission, which includes a first clutch with a first partial transmission and a second clutch with a second partial transmission, as well as a shifting system for engaging/releasing gears of the two partial transmissions. A first switching valve in a first position AI connects a first pressure regulator to the first clutch and disconnects it from the shifting system and in a second position BI connects the first pressure regulator to the shifting system and disconnects it from the first clutch, and that a second switching valve in a first position AII connects a second pressure regulator to the second clutch and disconnects it from the shifting system and in a second position BII connects the second pressure regulator to the shifting system and disconnects it from the second clutch.

Abstract: A process for actuating a transmission mechanism having hydraulic shifting elements for changing gear ratios by using electric actuators to adjust the actuating pressures of the shifting elements. Upon a request from an engine start/stop function for shutdown of an engine, the flow of electrical current to the actuators is changed from an operating level to a standby level depending upon the operating pressure of the shifting elements. Upon the request for startup of the engine, the flow or electrical current is changed from the standby level to the operating level. A system pressure in the hydraulic system is zero when the engine is shutdown, and the power consumption in the transmission mechanism is lower at the standby level than the operating level.

Abstract: A control system is provided. The control system includes a timer module that receives a first torque converter clutch (TCC) apply request and estimates at least one of a message latency time and a hydraulic latency time. A control module receives a subsequent TCC apply request and generates a torque request for an engine based on the at least one of the hydraulic latency time and the torque message latency time.

Abstract: An automatic transmission controller has an electronic control circuit, an electromagnetic valve, and a pressure control valve. The electronic control circuit generates a control current. The electromagnetic valve regulates a command pressure in accordance with the control current. The pressure control valve has a spool and is formed with a spool hole. The spool reciprocates in the spool hole in accordance with the command pressure to regulate a pressure supplied to a friction element of an automatic transmission. In a standby state, when the friction element is in a disengaged state, the electronic control circuit generates an oscillating current as the control current so that the electromagnetic valve generates a standby command pressure that makes the spool reciprocate in a range in which no pressure is supplied to the friction element.

Abstract: According to an aspect of the present invention, an automatic transmission includes plural friction engaging elements configures plural shift ranges based on combinations of each friction engaging element being in engaging or disengaging condition, a controlling unit for controlling the friction engaging elements to be in engaging or disengaging condition by controlling a hydraulic pressure applied.

Abstract: Many vehicles designed for running on rough terrain include an automatic transmission for performing speed change by connecting or disconnecting an oil hydraulic clutch provided alongside each speed change gear. However, depending on the posture of the driver, it may be impossible to step on the brake. As a result, it may be impossible to achieve creep prevention with a creep preventive mechanism dependent on a brake signal. Therefore, a creep preventive mechanism which operates independently from a brake signal is required. The present invention provides an oil pressure control system operating independently from a brake signal. The system includes an oil pressure supply source with a linear solenoid valve for supplying working oil or interrupting the supply of the working oil to the oil hydraulic clutches. The supply of the working oil to the clutches is interrupted when the vehicle is stopped under an idling condition of an engine.

Abstract: A method for reducing oscillation in an automotive transmission system includes detecting a tip-out of an accelerator pedal position. Responsive to the detected tip-out, a pressure command is adjusted for a selected range clutch within the transmission system so as to reduce the pressure of the selected range clutch from a normal pressure level to a low pressure level, thereby producing a desired gear train slip in the transmission system. Then, the pressure command of the selected range clutch is re-adjusted after a determined period of time at the low pressure level so as to increase the pressure of the selected range clutch from the low pressure level, and thereby eliminating the gear train slip.

Abstract: A hydraulic control unit including a hydraulic servo for engaging and disengaging each friction engagement element, hydraulic pressure supply device for supplying hydraulic pressure to a hydraulic servo of a predetermined friction engagement element selected according to a gearshift position to be achieved, failure detection device for detecting a failure has occurred in the hydraulic pressure supply device, and fail-safe device for preventing interlock that occurs due to a plurality of friction engagement elements being engaged, and also prevents a gearshift from a high-speed position to a low-speed position, when the failure detection device detects that a failure has occurred.

Abstract: A hydraulic control system includes switching mechanisms for receiving as a signal pressure a hydraulic pressure which is output from each shifting mechanism when all units of the shifting mechanisms are caused to output a hydraulic pressure, and being responsive to the reception of the signal pressure to be switched to a predetermined state for blocking a hydraulic-pressure supply path to specific hydraulic servos, thereby achieving a specific speed out of a plurality of speeds; and supply switching mechanisms provided in a hydraulic-pressure supply path to a hydraulic servo which is not included in the specific hydraulic servos, for switching between supply and cut-off of the hydraulic pressure to the hydraulic servo so as to assure two speeds in the event of the signal failure in a hydraulic control system for individually controlling engaging elements in an automatic transmission by using electric signals.

Abstract: A control for a power transmission has a neutral idle circuit comprised of a signal valve, a control valve and a shuttle valve. The signal valve supplies a bias pressure to the control valve, which has an output control pressure proportional to the input torque to the transmission. The output control pressure and transmission line pressure act on the shuttle valve to direct the control pressure to a clutch in the transmission when the output pressure is below a predetermined percentage of the transmission line pressure and to direct line pressure to the clutch when the predetermined percentage is exceeded. This permits the clutch to be controlled at or below a slipping engagement state.

Abstract: In a driven state, a hydraulic pressure of disengagement side is set at a stroke pressure, a one-way clutch in an operating state is over-run, an engine rotation speed is in an idle state, and an automatic transmission is in a neutral state. In a drive state, the hydraulic pressure of disengagement side is controlled so that a difference between an engine rotation speed and an input rotation speed reaches a difference between the both rotation speeds at a start of the shift control. In a state of a synchronized rotation after the shift, the hydraulic pressure of disengagement side is controlled so that the input rotation reaches the synchronized rotation.

Abstract: A speed change control method and apparatus for a vehicular automatic transmission having a first-speed clutch for establishing a first speed and a second-speed clutch for establishing a second speed, includes subjection of at least a duty ratio Dr of a second-speed solenoid valve for supplying oil pressure to the second-speed clutch to feedback control, so that the first-speed clutch is engaged while disengaging the second-speed clutch. This thereby increases a turbine rotational speed Nt toward the first-speed synchronous rotational speed. Further, an upper limit value Dmax of the duty ratio Dr is set, and the duty ratio Dr is subject to feedback control within a resultant duty ratio range. This thereby prevents the duty ratio Dr from being set at an excessive value caused by a delay in the rise of the oil pressure. As a result, even if a depression of an accelerator pedal is suddenly increased during a downshifting process, an interlock problem can be prevented, thereby ensuring smooth speed change.

Abstract: An automatic transmission control system includes a hydraulic circuit for controlling coupling pressure supplied to frictional coupling elements of the automatic transmission, which are selectively coupled and uncoupled so as to shift the automatic transmission into desired gears. The hydraulic circuit has a solenoid valve, for regulating a principal hydraulic pressure to provide a control pressure in accordance with vehicle driving conditions. The coupling pressure, supplied to a frictional coupling element, is regulated by a regulating valve in accordance with a control pressure level, and during shifting of the automatic transmission, is supplied through an accumulator whose back pressure is controlled in accordance with the control pressure by a control valve.

Abstract: Proposed is a method for manufacturing an optical memory disc having a pregrooved substrate and a recording film on the pregrooved substrate. In the step of depositing the recording film on the pregrooved substrate, light is incident on the pregrooved substrate, and at least one of exposure amounts of light reflected by and light transmitted through the pregrooved substrate and the recording film while the recording film is being deposited on the pregrooved substrate is measured. When one of the exposure amounts of light reflected by and light transmitted through the pregrooved substrate and the recording film has reached the corresponding preset exposure amount, the deposition of the recording film is stopped.