Aisin Seiki Kabushiki Kaisha

Toyota Jidosha Kabushiki Kaisha

Aisin Ai Co., Ltd.

Aisin Seiki Kabishuki Kaisha

Shigeki Goto

Masato Shimei

Yoshitami Saitou

Tetsuhiro Miyazawa

Nobuyuki Isono

Choji Furusawa

Isamu Minemoto

Satoshi Maruchi

Shigeo Takahashi

Takayoshi Tsuzuki

Takahiro Sakai

Masahiko Nakagawa

Yoshinori Kawajiri

A power transfer device for an inboard/outboard motor which includes a propeller unit mounted on the hull of a vessel, the propeller unit including an input shaft for drive connection to an output shaft of the inboard/outboard motor, an intermediate shaft connected to a propeller shaft, a hydraulic clutch provided on the input shaft to establish a drive power train between the input shaft and intermediate shaft when it has been engaged and to disconnect the input shaft from the intermediate shaft when it has been disengaged, and a changeover mechanism of the gear selection type disposed between the input shaft and intermediate shaft for switching over the drive power train from a forward drive to a backward drive or vice versa. The power transfer device is provided with a hydraulic control apparatus for operating the changeover mechanism in shifting operation to switch over the drive power train from the forward drive to the backward drive or vice versa in a condition where the hydraulic clutch is maintained in its disengaged condition and for engaging the hydraulic clutch after the drive power train has been switched over from the forward drive to the backward drive or vice versa.

Power transfer device for inboard/outboard motor

A control apparatus for an automatic transmission having a set of frictional engagement elements arranged to be selectively engaged or disengaged in shift-up operation of the transmission, and a shift timing valve arranged to be switched over by hydraulic pilot pressure applied there-to under control of a solenoid valve for switching over discharge of fluid under pressure from one of the frictional engagement elements to be disengaged in the shift-up operation from a slow-drain condition to a quick-drain condition. The control apparatus is designed to detect a drive torque of a vehicle engine, to determine a timing period for energization of the solenoid valve in the shift-up operation in accordance with the drive torque of the vehicle engine, to maintain the solenoid valve in its deenergized condition during the timing period, and to energize the solenoid valve upon lapse of the timing period.

Control apparatus for automatic transmission

During a shift operation, a time interval TT which is required to switch a mechanical gear ratio is detected. To bring it into coincidence with a reference value, the duty cycle with which a linear solenoid valve SL6 which determines a back pressure on an accumulator is energized is adjusted. The duty cycle is adjusted in accordance with an oil temperature, a throttle valve opening and a shift mode of an automatic transmission in order to prevent the occurrence of shift shocks as a result of a variation in the shift response of the automatic transmission from transmission to transmission or with time.

Hydraulic control system with condition responsive accumulator control

A shift control apparatus for an automatic transmission includes a kickdown orifice control valve for changing over two systems of hydraulic-pressure supply lines which supply hydraulic pressure to friction engaging elements on an engaging side via at least one orifice by sliding a spool between a first position at which the spool is urged by a spring and a second position at which the spool is urged by changeover hydraulic pressure acting in a direction opposite the spring, a solenoid valve mounted at a point along a line which introduces the changeover hydraulic pressure, and control means for controlling opening and closing of the solenoid valve, e.g., by duty-control or timer. Duty control is made according to vehicle velocity and throttle opening and corrected according to the engine rotational state.

Shift control apparatus for automatic transmissions

An hydraulic control device for an automatic transmission includes a plurality of controlling valves connected to related friction engaging elements. A plurality of solenoid valves are connected to the controlling valves for supplying hydraulic pressure thereto. A checking device determines whether an upshift of the transmission is performed or not. A detector determines a detected value of either a RPM count of an engine of the vehicle or a longitudinal acceleration of the vehicle. A fail-safe device prevents the upshift based on a comparison of the detected value with a predetermined value.

Hydraulic control device for automatic transmission

Hydraulic control system for automatic transmission

An apparatus and method for synchronizing shifting of a main transmission and a subtransmission, particularly in automatic transmissions having more than four speed ranges. Synchronism is achieved by initiating the shifting of the main transmission when the speeds of the input and output shafts of the main transmission achieve a predetermined relationship.

Automatic transmission

For a 2.fwdarw.1 shift, a timing solenoid valve SL5 is maintained at a duty cycle of 0% (off) for an interval TE=1.5 sec from the initiation of the shift operation and then the duty cycle is changed to 100% (on) after the TE interval so that an oil pressure of a brake B.sub.2 is maintained low during the shift operation while the oil pressure is increased to a high oil pressure for transfer of a maximum torque used in the first speed range upon completion of the shift operation. In response to a switching of a shift lever from D or S range to L range, the timing solenoid valve SL5 is energized with a duty cycle of 100% (on) at 2 sec after such switching to provide a high oil pressure for transfer of the maximum torque, thus preventing a shift shock from occurring as a result of a switching from D or S to L range. Since a control over the oil pressure through the timing solenoid valve SL5 during the shift operation takes place by switching an energization level of the solenoid SL5, the oil pressure can be switched in an accurate manner.

A shift control device for an automatic transmission comprises a shift valve, a solenoid valve connected to the shift valve, a shift timing valve also connected to the shift valve, a cut-off device connected to the solenoid valve and the shift timing valve, and a timing solenoid valve connected to the cut-off device so as to avoid the problem of shift shock which occurs when the timing solenoid valve is in an abnormal operating condition.

Shift control device for an automatic transmission

A hydraulic control apparatus for an automatic transmission has friction elements for performing a downshift by releasing one friction engaging element and engaging another. The apparatus includes duty control valves connected to the friction engaging elements, duty solenoid valves connected to oil lines for supplying pilot hydraulic pressure to the duty control valves, and control means. In a case where a release duty signal is outputted to one duty solenoid valve to control the pilot hydraulic pressure to thereby release the one friction engaging element, and downshift is a power-on downshift, the control means raises the duty ratio of the other duty solenoid valve to a predetermined valve to raise engaging hydraulic pressure supplied to the other friction element when rotational speed of the transmission input shaft is greater than a difference between the product of output shaft rotational speed and low-side gear ratio and a rotational speed commensurate with a delay in engine speed upturn.

Hydraulic control apparatus for automatic transmissions

A control apparatus for an automatic transmission connected to a hydraulic control circuit having a first changeover valve for switching a main transmission mechanism having at least two speed ratios between high and low speed ratios in dependence upon at least vehicle velocity, and a second changeover valve for switching an auxiliary transmission mechanism, which is provided in addition to the main transmission mechanism and has at least two speed ratios, between high and low speed ratios at a vehicle velocity higher than a changeover velocity of the first changeover valve. The control apparatus has a third changeover valve for switching the auxiliary transmission mechanism from low to high at a vehicle velocity lower than the changeover velocity of the first changeover valve, and from high to low when the vehicle velocity rises above the changeover velocity of the first changeover valve. The third changeover valve is capable of forming an intermediate speed, such as a 1.5 or 2.5. speed, by changing over the auxiliary transmission mechanism from low to high while the main transmission mechanism is low.

Intermediate shift control apparatus for automatic transmission

In an automatic transmission having a torque converter, a planetary gear mechanism receiving an output from the torque converter and including brakes and clutches, and a hydraulic pressure circuit for actuating the brakes and clutches. An arrangement is provided for varying servo hydraulic pressure, which is for achieving low gear, in dependence upon vehicle velocity.

Automatic transmission control system incorporating an exhaust brake

An exhaust brake control system includes an input switch for commanding actuation of an exhaust brake, a throttle sensor for sensing that an accelerator pedal has been depressed in excess of a predetermined angle, a control unit for outputting a control signal in dependence upon output signals from the input switch and throttle sensor, and a valve means for opening and closing an exhaust passageway in dependence upon a control signal produced by the control unit. The control unit includes a shift sensor for sensing at least an L-range shift of an automatic transmission, and a servo hydraulic pressure sensor for sensing servo hydraulic pressure that actuates a servo piston for establishing 1st speed range. When the shift sensor senses that the automatic transmission has been shifted to the L range, the control unit outputs a control signal for actuating the valve means to open the exhaust gas passageway at such time that the servo hydraulic pressure sensor outputs a signal indicative of a value greater than a predetermined value. Exhaust braking is applied following attainment of a sufficiently high servo hydraulic pressure immediately after a downshift, thus preventing the engine from stopping at application of exhaust braking. The same is applied to downshifting to '2' range.

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Kariya, Japan

Shigeki Goto