Honda Giken Kogyo Kabushiki Kaisha

Honda Giken Kabushiki Kaisha

Hideki Wakamatsu

Tatsuyuki Ohashi

Takamichi Shimada

Takayuki Yamaguchi

Yoshiharu Saito

Takafumi Sakai

Shoji Asatsuke

Yoshihiro Tsuboi

Norio Nakauchi

Yukio Morita

Kenji Hagiwara

Kazuyuki Konno

Kenichi Haraguchi

Noboru Sekine

Toru Yamashita

Masaaki Takamatsu

Shouji Asatsuke

Tomonari Shirai

Masaya Kawauchi

Hitoshi Kondo

Yutaka Yamamoto

A system for controlling an automatic transmission of a vehicle which determines a downgrade or upgrade parameter based on the vehicle acceleration and selects one from among a plurality of shift programs based on the determined grade parameter to determine a gear ratio based on the selected shift program. The system includes a navigation system which determines the instantaneous vehicle position and outputs road information including upgrade/downgrade condition of road including the determined instantaneous vehicle position. In the system, the grade parameter is corrected based on the navigation information and the grade parameter such that the one from among a plurality of shift programs is selected based on the corrected grade parameter, thereby enhancing drivability during downgrade running, without being affected even if the navigation information is temporarily invalid.

Control system for automatic vehicle transmissions

The present invention provides a shift control valve that controls the supply of engagement control hydraulic pressure to a drive friction engagement element and a reverse friction engagement element, having first and second main pressure oil lines (such as oil lines and ) provided in parallel between a manual valve and an oil line (main pressure supply source) linked to a main regulator valve oil lines and that connect the manual valve to a LOW clutch and oil lines and that connect the manual valve to a reverse clutch and a first linear solenoid valve (linear A) that allows the main pressure to be set as desired being provided to at least one of the first and second main pressure oil lines.

Shift control device for automatic transmission

A shift control system for an automatic transmission comprises a shift lever , which is shifted among a &ldquo;P&rdquo; position, an &ldquo;N&rdquo; position and an &ldquo;S&rdquo; position. A first shift guide path is provided to guide the shift lever from the &ldquo;P&rdquo; position through the &ldquo;N&rdquo; position to the &ldquo;S&rdquo; position, and a second shift guide path is provided to guide the shift lever which has been positioned at the &ldquo;S&rdquo; position in a direction different from that of the first shift guide path. Along this second shift guide path, the shift lever is shifted to select and set a plurality of ranges necessary for driving a vehicle, including a forward drive range, a neutral range and a reverse drive range.

Shift control system for vehicular automatic transmission

A control system for an automatic transmission comprises a forward/reverse selection hydraulic servomechanism a D inhibitor valve, which controls the supply of a line pressure to the servo-oil chambers of this servomechanism, and a plurality of solenoid valves which are used for controlling the actuation of the shift valves and the D inhibitor valve. This control system comprises a first neutral mode and a second neutral mode for a neutral range. In the first neutral mode, the D inhibitor valve is switched to a forward drive position, and the forward drive servo-oil chamber is connected to a drain. In the second neutral mode, the D inhibitor valve is switched to a reverse drive position, and the forward drive and reverse drive servo-oil chambers are both connected to the drain.

Automatic transmission control system

An automatic transmission comprises a plurality of clutches , which are provided to select power transmission paths, respectively, in a parallel shaft speed change mechanism TM and a plurality of shift valves , which are used for controlling the supply and drain of hydraulic oil to and from these clutches. For this automatic transmission, a control system comprises a plurality of solenoid valves , which are used for controlling the supply and drain of a line pressure so as to control the actuation of these shift valves. This system, when the shift lever is manipulated to set the neutral range, sets the transmission into either a first neutral mode or a second neutral mode depending upon the speed of the vehicle, the first neutral mode being set when the vehicle is driving at a speed equal to or more than a critical speed, and the second neutral mode being set when the vehicle speed is less than the critical speed. In this control, the combination of on/off operations of the solenoid valves for setting the first neutral mode is different from the combination for setting the second neutral mode.

An automatic transmission comprises a plurality of clutches which are provided to select power transmission paths, respectively, in a parallel shaft speed change mechanism TM and a plurality of shift valves which are used for controlling the supply and drain of hydraulic pressure to and from these clutches. For this automatic transmission, a control system comprises a forward/reverse selection hydraulic servomechanism 70 and a plurality of solenoid valves which are used for controlling the supply and drain of a line pressure so as to control the actuation of these shift valves and the forward/reverse selection hydraulic servomechanism. The system further comprises a hydraulic switch which detects the hydraulic pressure supplied into the right side oil chamber of the forward/reverse selection hydraulic servomechanism and a hydraulic switch which detects the hydraulic pressure of the SECOND speed clutch whose pressure is generated from the pressure in the right side oil chamber The system determines whether the forward drive range is set correctly or not, based on a result of pressure detection by these hydraulic switches and

An automatic transmission comprises a forward/reverse selection hydraulic servomechanism which actuates a dog clutch and a plurality of clutches and For this automatic transmission, a control system comprises first&tilde;fifth on/off solenoid valves and first&tilde;third linear solenoid valves These valves are used to control the supply and drain of a line pressure to and from the forward/reverse selection hydraulic servomechanism and first&tilde;fifth shift valves and so as to control the actuation thereof for the selective engagement of the clutches. This system, when it detects, by a hydraulic switch a condition that the D range is selected and that the actuation command signals being sent to the solenoid valves correspond to one of the signal combinations which are used for setting the driving modes of the D range, allows the actuation of the solenoid valves by these actuation command signals.

A system for controlling an automatic transmission of a vehicle which determines a downgrade or upgrade parameter based on the vehicle acceleration and selects one from among a plurality of shift maps (programs) based on the determined grade parameter to determine a gear ratio based on the selected shift program. The system includes a navigation system which stores the road information including the kinds of road. The system determines whether the vehicle runs on a relative road such an alley or a traffic jammed expressway based on the vehicle speed change, the vehicle-stopping-time and the navigation information and if it does, changes the upshift line of the level-road map in the direction in which the vehicle speed increases such that upshift is not likely to occur, or in the direction in which the vehicle speed decreases such that the upshift is more likely to occur, thereby enhancing driveability.

A valve body assembly for an automatic transmission formed by superimposing and clamping a torque converter casing, a first separation plate, a main valve body, a second separation plate, a second valve body, a third separation plate and a servo body. Pairs of first separation plates and pairs of second separation plates are provided, one pair for 7-position types of automatic transmissions and another pair for 6-position types of automatic transmissions and are, respectively, selected, used and assembled between the converter casing and main valve body and the main valve body and second valve body depending upon whether a 7-position type of transmission or a 6-position type of transmission is being assembled. Thus, general purpose properties are provided to the valve body assemblies used in hydraulic pressure control systems for 7-position type and 6-position type automatic transmissions for vehicles and the like.

Hydraulic pressure control system

A control apparatus for a hydraulically operated vehicular transmission having a plurality of hydraulic engaging elements has an accumulator which is connected in parallel with a hydraulic engaging element for a low-speed transmission train and a back pressure generating source which generates a hydraulic oil pressure to be supplied to a back pressure chamber of the accumulator. The control apparatus includes a changeover valve which can be changed over between a first position in which the back pressure chamber of the accumulator and the back pressure generating source are brought into communication with each other and a second position in which the communication is cut off to lower a pressure in the back pressure chamber. The changeover valve is arranged to be changed over from the second position to the first position when a hydraulic oil pressure in the hydraulic engaging element for the low-speed transmission train has exceeded a predetermined pressure.

Hydraulic bypass to back pressure chamber of a clutch accumulator

In a control apparatus for a hydraulically operated vehicular transmission which has a plurality of hydraulic engaging elements, an orifice is disposed in an oil passage which is communicated with a hydraulic engaging element for a low-speed transmission train. The control apparatus has a bypass passage which bypasses the orifice, a control valve which can be switched between a communicated state in which the bypass passage is in communication and a cut-off state in which the communication of the bypass passage is cut off, and a control circuit which changes over the control valve to the communicated state under a predetermined condition at a time of switching from a running range to a neutral range.

Control apparatus for hydraulically operated vehicular transmission

The transmission is of a type that a low-speed transmission train is established in cooperation with one-way clutch. A high-speed transmission train is established by hydraulic oil supply via a shift valve in a condition in which the hydraulic oil is kept supplied to the low-speed hydraulic engaging element. A pressure adjusting valve and a hydraulic oil pressure control valve control, to increase or reduce, the supply pressure of the hydraulic oil to the high-speed hydraulic engaging element. A speed change controller at an initial stage maintains the shift valve, at the time of speed changing from a high-speed transmission train to a low-speed transmission train, in a condition in which the hydraulic oil is supplied to the high-speed hydraulic engaging element. The supply pressure of the hydraulic oil is reduced in this condition until the high-speed hydraulic engaging element gives rise to a slip. The supply pressure of the hydraulic oil is maintained in the condition of reduced pressure until the one-way clutch is engaged and thereafter the shift valve is changed over to a condition in which the hydraulic oil is discharged from the high-speed hydraulic engaging element.

A control apparatus for a hydraulically operated vehicular transmission has a plurality of hydraulic engaging elements including a first hydraulic engaging element which is kept engaged in a plurality of transmission trains. The control apparatus has an accumulator which is connected, via a branched oil passage, to a working oil passage which is communicated with the first hydraulic engaging element. It also has a control valve which is disposed in the branched oil passage and which can be moved between a first position in which an upstream portion of the branched oil passage on a side of the first hydraulic engaging element and a downstream portion of the branched oil passage on a side of the accumulator are brought into communication with each other and a second position in which the communication is shut off. It further has an oil discharge passage which is connected to a second hydraulic engaging element when the second hydraulic engaging element is disengaged. This oil discharge passage is arranged to be connected to the downstream portion of the branched oil passage in the second position of the control valve.

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Wako, Japan

Hideki Wakamatsu