摘要:
In an automatic transmission for a vehicle having an input rotational member, an output rotational member, a rotational speed change gear mechanism, clutches and brakes for changing a route of transmittance of torque between the input rotational member and the output rotational member through the rotational speed change gear mechanism in accordance with selective engagement and disengagement of the clutches and brakes so as to provide a plurality of forward speed stages and a reverse stage, a first one of the clutches is constructed to house a second one of the clutches at a radially inside thereof with a piston member of the first clutch serving as a member for transmitting torque through the second clutch, the second clutch being never engaged immediately after disengagement of the first clutch under any operating condition of the vehicle.
摘要:
In an automatic transmission for a vehicle such as an automobile having a speed stage shifting mechanism including parallelly arranged first and second input clutches C1, C2 and adapted to selectively engage the first and second input clutches in three ways of engaging the first input clutch C1 with the second input clutch C2 being disengaged to provide a certain first speed stage (2nd speed stage), engaging the second input clutch C2 with the first clutch C1 being disengaged to provide a certain second speed stage (4th speed stage) and engaging both the first and second clutches C1, C2 to provide a certain third speed stage (3rd speed stage), a hydraulic control device has a first valve (3-4 shift valve) for switching over connection of the first input clutch C1 with a hydraulic pressure supply 274 and a drain 280, a second valve (2-3 shift valve) for exchanging connection of the second input clutch C2 and a fail safe port 260 with a hydraulic pressure supply 246 and a drain 252, 253, and a passage 268 for connecting the drain for the first valve with the fail safe port 260 of the second valve so that at least one of the first and second input clutch is supplied with hydraulic pressure regardless of sticking of the first and/or the second valve.
摘要:
A vehicle transmission including a first, a second and a third planetary gear unit coaxially disposed between an input and an output member. The three units have respective first, second and third sun gears, respective first, second and third planetary gears, respective first, second and third carriers, and respective first, second and third ring gears. The first carrier, second ring gear, third sun gear and output members are connected to each other, while the second carrier and the third ring gear are connected to each other. The transmission has a first and a second coupling device for connecting the first ring and sun gears to the input member, respectively, a third and a fourth coupling device for connecting the first sun gear to the second sun gear and to the second carrier and third ring gear, respectively, a fifth coupling device for fixing the third carrier to a stationary member, a sixth coupling device, for fixing the second carrier and third ring gear to the stationary member, and a seventh coupling device for fixing the second sun gear to the stationary member.
摘要:
For an automatic transmission for a vehicle such as an automobile having a speed stage shifting mechanism including parallelly arranged first and second hydraulically operated input clutches and adapted to provide the 3rd speed stage in which the first and second input clutches C.sub.1 and C.sub.2 are both engaged and the overdrive 4th stage in which the clutch C.sub.1 is disengaged and the clutch C.sub.2 is engaged, the engagement of the clutch C.sub.1 in the 3rd speed stage being not essential unless engine brake availability is required, a hydraulic control device has a hydraulic pressure supply control device for variably controlling speed of supply of a hydraulic pressure to the first input clutch C.sub.1 according to conditions for engaging the first input clutch such whether it is a kickdown of an overdrive inhibition, and a hydraulic pressure exhaustion control device for controlling speed of exhaustion of a hydraulic pressure from the first input clutch C.sub.1 independently of the hydraulic pressure supply control device to be substantially higher than the speed in the supply.
摘要:
In an automatic transmission to provide a plurality of forward speed stages for a vehicle having a transversely mounted engine, a counter drive gear serving as a power output member of the speed change gear device to drive a counter shaft is positioned between a planetary gear mechanism of the speed change gear device and the torque converter, and the forward clutch which is engaged to provide a plurality of forward speed stages is positioned between the torque converter and the counter drive gear.
摘要:
A hydraulic pressure control device for an automatic transmission for a vehicle, including a first, a second and a third hydraulic pressure control valve, wherein the third hydraulic pressure control valve cooperates with the first hydraulic pressure control valve to control switching over of a certain operation of the automatic transmission such as engagement and disengagement of a torque converter lock-up clutch during forward traveling of the vehicle, and also cooperates with the second hydraulic pressure control valve to selectively prevent setting up of the reverse stage when a manual shift valve is set to the reverse range while the vehicle is traveling forward.
摘要:
In a four wheel drive vehicle, wherein either a state where differential action between front wheels and rear wheels is restricted or a permitted state can be selected, the differential rate is calculated during stable running conditions, and, when the differential rate is greater than or equal to a predetermined value, the restriction of differential action is prohibited. As a result, power circulation can be prevented when there is a difference in effective radius between the front wheels and rear wheels due to, e.g., use of a temper tire, mounting of chains on the tires, or the like.
摘要:
For an automatic transmission for a vehicle including a speed stage shifting device such as shown in FIG. 1 in which the clutch C.sub.1 is adapted to be engaged when the 2nd speed stage and the 3rd speed stage are set up and disengaged when the 4th speed stage is set up, the engagement of the clutch C.sub.1 being essential for setting up the 2nd speed stage while the engagement of the clutch C.sub.1 is not essential for setting up the 3rd speed stage unless engine brake availability is required, a hydraulic control device includes a first passage 235 and a second passage 329 for supplying a hydraulic pressure to the clutch C.sub.1 in parallel with one another, the first passage having a substantially less fluid flow resistance than the second passage, and a fluid flow switching over mechanism including a 1-2 shift valve 210 and a C.sub.1 control valve 300 for alternatively communicating the first or the second passage while interrupting the second or the first passage according to whether the 2nd speed stage or the 3rd speed stage is set up. An accumulator 450 may be provided in the second passage 329. Further, a one way val e 469, or more desirably a parallel connection of the one way valve 469 and an orifice 467 may be provided between the accumulator and the clutch C.sub.1.
摘要:
In an automatic transmission for a vehicle such as an automobile having a speed stage shifting mechanism including parallelly arranged first and second hydraulically operated input clutches and adapted to provide the 3rd speed stage in which the first and second input clutches C.sub.1 and C.sub.2 are both engaged (though the engagement of the clutch C.sub.1 in the 3rd speed stage is not essential unless engine brake availability is required) and the overdrive 4th stage in which the clutch C.sub.1 is disengaged and the clutch C.sub.2 is engaged, the clutch C.sub.1 in the 3rd speed stage being not essential unless engine a hydraulic control device has a switching over valve 330 for switching over supply of a hydraulic pressure to the first clutch C.sub.1 between a first mode of relatively slowing supplying the hydraulic pressure to the first clutch C.sub.1 and a second mode of relatively quickly supplying the hydraulic pressure to the first clutch C.sub.1 according to engine output power so as to select the second mode when engine output power is higher than a determinate power level as in the downshifting by kickdown and to select the first mode when engine output power is less than the determinate power level as in the overdrive inhibition.
摘要:
A hydraulic pressure control device for an automatic transmission for a vehicle, including a spool type hydraulic pressure control valve for selectively prevent setting up of the reverse stage when a manual shift valve is set to the reverse range while the vehicle is traveling forward, wherein the spool element of the hydraulic pressure control valve is positively shifted to a position for not preventing the setting up of the reverse stage by a hydraulic pressure available when the manual shift valve is set to the forward range.