Honda Giken Kogyo Kabushiki Kaisha

Honda Giken Kogyo K.k.

Yukihiro Fukuda

Masao Nishikawa

Yoichi Sato

Takashi Aoki

Yoshimi Sakurai

Junichi Miyake

Shinzo Sakai

An automatic shift transmission for vehicles of the type in which the shifting of speed is automatically effected with a changeover valve having an orifice installed upstream thereof and a pilot type solenoid valve installed downstream thereof. A pressure reducing valve is provided upstream of the orifice. The amount of hydraulic oil consumed through the solenoid valve is possibly reduced.

Automatic shift transmission for vehicles

A method of controlling a direct-coupling mechanism of hydraulic power transmission device of an automatic transmission for an automotive vehicle, wherein the transmission capacity of the direct-coupling mechanism is controlled such that the valve of a predetermined parameter indicative of an amount of relative slip between input and output members of the hydraulic power transmission device which are mechanically engaged with each other by the direct-coupling mechanism lies within a predetermined reference range. The predetermined parameter value is detected and the detected value is compared with the predetermined reference range. A desired value of the predetermined reference range and a predetermined period of time are determined on the basis of the comparison result. The transmission capacity is controlled to the determined desired value for the determined predetermined period of time. The transmission capacity is maintained so long as the detected predetermined parameter value lies within the predetermined reference range. At least first and second transmission capacity increasing regions are provided which correspond to larger values of the amount of relative slip than that the predetermined reference range corresponds to, wherein the first region is closer to the predetermined reference range than the second region is. A rate of increase of the transmission capacity in the first region is set to a value smaller than that in the second region. A fine-control region is provided adjacent at least one of extreme limits of the predetermined reference range, wherein the transmission capacity is finely adjusted toward the predetermined reference range.

Control method for a direct-coupling mechanism in hydraulic power

A method of controlling a direct-coupling mechanism of a hydraulic torque converter of an automatic transmission for an automotive vehicle, wherein the transmission capacity of the direct-coupling mechanism is controlled such that the value of a first predetermined parameter indicative of an amount of relative slip between input and output members of the hydraulic torque converter which are mechanically engaged with each other by the direct-coupling mechanism lies within a predetermined reference range. The value of a second predetermined parameter indicative of one of said plurality operating modes for the automotive vehicle is detected. Determined in dependence on the detected value of the second predetermined parameter is either the predetermined reference range of the value of the first predetermined parameter or a rate at which the transmission capacity is controlled such that the value of said predetermined parameter changes toward the predetermined reference range of the first predetermined parameter.

Method of controlling transmission capacity of a direct-coupling

A frictionally engaging device for power transmission of a vehicle, has a first pressure chamber defined in part by one side of a piston urging frictionally engaging elements into engagement with each other, and a second pressure chamber defined in part by the other side of the piston for accommodating the frictionally engaging elements. A hydraulic pressure control arrangement controls operating fluid pressure supplied to the first pressure chamber at least to a value higher than a first predetermined value which causes engagement of the frictionally engaging elements and to a second predetermined value lower than the first predetermined value, which inhibits creeping of the frictionally engaging elements. When the operating fluid pressure is lower than the second predetermined value, a first valve opens to allow escape of the operating fluid from the second pressure chamber to the first pressure chamber. When the operating fluid pressure is at least lower than the first predetermined value, a second valve opens to permit flow of the operating fluid from the first pressure chamber to the second pressure chamber, to thereby cool the frictionally engaging elements.

Hydraulic clutch for motor vehicles, having creep-inhibiting feature

A control system for an accessory of an automobile includes an engine output detector for detecting the output of the engine of the automobile, a gear transmissioon coupled to the engine and responsive to detection of an idling condition of the automboile for selecting a neutral gear position, an accessory such as an air conditioner compressor drivable by the engine, a clutch disposed between the accessory and the engine for applying and cutting off the output of the engine to the accessory, a speed sensor for detecting the speed of travel of the automobile, a control circuit for comparing an actual running condition of the automobile with a prescribed running condition in which the output of the engine and the speed of the automobile are lower than respective prescribed levels, and for inhibiting operation of the accessory by disconnecting the clutch when the automobile is under the prescribed running condition.

Control system for engine-operated automotive accessories

An automatic transmission includes a mechanical transmission mechanism coupled to a fluid coupling. The mechanical transmission mechanism has several power trains and several friction engagement mechanisms. By selective supply of actuating fluid pressure to selective ones of the friction engagement mechanisms, various speed stages are provided. A control system for this transmission includes a mechanism for producing a signal representative of engine output and an anti creep device for varying the actuating hydraulic fluid pressure for one of the friction engagement mechanisms which is engaged for providing the lowest speed stage, according to the signal representative of engine output, from a low value when engine output is low upward as engine output increases. The anti creep device may include a hydraulic fluid chamber whose volume alters during alteration of amount of applying of anti creep action, and a fluid conduit system for connecting this hydraulic fluid chamber to the outside with a flow resistance which is different in the outwards direction and the inwards direction. Alternatively, the anti creep device may vary the actuating hydraulic fluid pressure for that one of the friction engagement mechanisms, according to the signal representative of engine output, upward from a low value when the signal is low, as the signal increases, substantially in proportion to the signal, up to a certain value of the signal; and may then set, for values of the signal greater than the certain value, the actuating hydraulic fluid pressure substantially equal to a certain maximum value.

Automatic transmission with anti creep device

In a creep preventing device for vehicles equipped with an automatic transmission comprising: a fluid type torque converter; an auxiliary transmission having a frictionally engaging element for starting and connected to the torque converter; and a creep preventing valve disposed in an oil passage branched from an operating oil passage leading to the frictionally engaging element to communicate with an oil tank and adapted to open the oil passage during the idle operation of the vehicle, the improvement wherein the creep preventing valve includes an oil chamber for closing the valve when oil pressure above a predetermined level is introduced thereto, and an oil passage for guiding the oil pressure from an engine output proportional signal pressure generating means, which releases the signal pressure proportional to the engine output, is connected to the oil chamber, whereby the engaging force of the clutch for starting can be controlled in an analog fashion to ensure the smooth reengaging operation of the clutch.

Creep preventing device for vehicle equipped with automatic transmission

A creep-inhibiting device for use in an automotive vehicle equipped with an engine and a transmission mechanism coupled in series to a fluid coupling and having a frictionally engaging element. The device includes engine load sensor means for producing a signal fluid having a pressure representative of engine load, control means interposed between the frictionally engaging element and an operating fluid source, and a fluid line for delivering the signal fluid from the engine load sensor means to the control means. The control means is adapted to control the power transmission capacity of the frictionally engaging element within a range from substantially zero to a predetermined value in dependence on the signal fluid pressure supplied thereto, to inhibit creeping of the vehicle when the engine is in a no-load state. Selector valve means is arranged in the fluid line and adapted to assume a first position wherein it allows the signal fluid to flow in both directions from the engine load sensor means to the control means and vice versa when the pressure of the signal fluid is lower than a predetermined value, and to assume a second position wherein it allows the signal fluid to flow in a sole direction from the engine load sensor means to the control means when the pressure of the signal fluid is higher than the predetermined value.

Creep-inhibiting device for an automotive vehicle equipped with an

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.

Growing community of inventors

Asaka, Japan

Yukihiro Fukuda