Abstract: Disclosed is a gear shift controller for an automatic transmission with a gear shift, having a hydraulic torque converter; a gear change group, having a plurality of gears, each gear providing a different transmission ratio for the transmission of power from said hydraulic converter to the output of the transmission, each of said gears having a gear train; a one-way clutch interposed in at least one of said gear trains; a plurality of clutch means operatively connected with said gear trains for actuating each of said gear trains selectively; a gear change determination circuit operatively connected with said clutch means for controlling the operation of each of said clutch means according to a predetermined gear-shifting program; a coasting detection circuit operatively connected with said gear change determination circuit, for detecting a car in the coasting state; a gear shift limiting circuit, operatively connected with said gear change determination circuit, for actuating only said gear train in which sai

Abstract: A method and device for controlling a plurality of magnet valves in an automatic transmission having a fluid torque converter, an anxiliary transmission equipped with a plurality of gear trains for transmitting the output torque of said torque converter to drive wheels through one of the selected gear trains, a plurality of shift valves to select said gear trains, and a plurality of magnet valves to drive said shift valves, wherein at least one of the magnet valves, which is subsequently driven to take an open-state at a time the gear train shifts up from the lowest speed to the second lowest speed, is closed at about the time of stalling of said torque converter and those magnet valves other than said closed magnet valve are opened after a short time delay after said magnet valve is opened when the vehicle velocity reaches the second lowest speed.

Abstract: Disclosed is a control device for a direct clutch in a vehicular automatic transmission comprising: a fluid torque converter; an auxiliary transmission having plural stages of gear trains selectively connected to the output side of said torque converter, said gear trains having different gear-to-gear speed ratios, and a plurality of hydraulically operated frictional engagement means for actuating the gear trains; and a hydraulically operated direct clutch capable of directly coupling pump and turbine vane wheels of the torque converter together. The control device includes first and second branch passages extended from working fluid passages of one and another of the frictional engagement means, respectively, a first directional control valve interposed between the first branch passage as well as an oil tank and an intermediate passage, and a second directional control valve interposed between the second branch passage as well as the intermediate passage and a working fluid passage of the direct clutch.

Abstract: A direct-coupling controller for a torque converter direct-coupling clutch in an automatic transmission. The controller includes a pilot oil pressure operated timing valve which interconnects the hydraulic cylinders of at least two of the hydraulically operated friction elements of the transmission to the hydraulic-cylinder of the direct-coupling clutch. The timing valve has two positions, a first where one of the friction elements is connected to the clutch and a second where the other is. Structure can be provided to delay movement of the timing valve spool member for a predetermined time. Additionally, a reduction valve can be interposed between the timing valve and the clutch to keep the oil pressure to the clutch at a predetermined level. A vehicle speed response valve can also be interposed between the timing valve and the clutch in parallel with the reduction valve to bypass the reduction valve when the vehicle speed exceeds a predetermined value.

Abstract: Automatic transmission having a direct coupler in the torque convertor which is operated by at least two solenoid operated pilot valves which are energized by a controller sensing running conditions of the vehicle.

Abstract: A control system for an automatic transmission for a vehicle with an electric vehicle speed detector, the automatic transmission including a torque converter with a semi-direct coupling mechanism hydraulically controllable of the degree of coupling.The control system comprises a signal processing circuit for processing an electrical vehicle speed signal to provide an electric control signal, and an electro-magnetic valve mechanism for selectively supplying a multi-staged hydraulic control pressure to the semi-direct coupling mechanism in accordance with the electric control signal.Automatic transmissions of the above type are applied to a vehicle with an electric vehicle speed detector, without any major change of existing production system and at an inexpensive cost.

Abstract: A control apparatus for a torque convertor clutch in a transmission including a circuit for engaging the clutch to mechanically interconnect a pump to a turbine of the torque convertor and a mechanism for disabling the circuit when the engine output increases above a predetermined set output value thereby releasing the clutch from engagement. A release preventing mechanism operatively associated with the release mechanism is provided to prevent operation of the release mechanism when the vehicle speed increases above a predetermined set speed value even though the engine output increases above the predetermined set output value.