摘要:
A power transmitting system having an input shaft, a driven bevel gear, a follower bevel gear and a clutch drive shaft accommodated in center casings. Left and right electromagnetic clutches connected to the clutch drive shaft are accommodated in left and right side casings. Oil for lubricating the electromagnetic clutches is supplied from an oil pump accommodated in the center casings and driven by the clutch drive shaft through oil passages and axially defied in the clutch drive shaft and left and right output shafts. Thus, the length of the oil passages for supplying the oil from the oil pump to the clutches can be minimized to provide a reduction in size of the power transmitting system.
摘要:
A rear differential in a four-wheel drive vehicle includes a left and right clutches adapted to distribute a driving force transmitted from front wheels through a propeller shaft to left and right rear wheels. If the engagement of the left and right clutches is released, only the front wheels are driven and in this manner, the vehicle is brought into a front wheel-drive state. If the left and right clutches are brought into their engaged states, both of the front wheels and the rear wheels are driven and in this manner, the vehicle is brought into a four-wheel drive state. By changing the engagement forces of the left and right clutches, different driving forces can be distributed to the left and right rear wheels. In addition, when a driver operates a differential lock switch, the left and right clutches, are brought into their engaged states with the maximum engagement force, thereby integrally coupling the propeller shaft to the left and right rear wheels to provide a differential-locked state. Thus, a differential lock mechanism can be provided to the differential in a simple structure.
摘要:
A 4-wheel drive vehicle has a driving force control method in which a portion of a driving force for front wheels is distributed to rear wheels through clutches. In a 4-wheel drive state in which a driving force T.sub.p is distributed to rear wheels, for example, if the vehicle is turned leftwards to generate a difference W.sub.R -W.sub.L between left and right rear wheel speeds, it is ensured that a driving force T.sub.R distributed to the right rear wheel, which is an outer wheel during turning of the vehicle, is larger than a driving force T.sub.L distributed to the left rear wheel, which is an inner wheel during turning of the vehicle, thereby providing an enhancement in turning performance. As the difference W.sub.R -W.sub.L between the left and right rear wheel speeds is increased as a result of decreasing of the turning radius of the vehicle, the driving force T.sub.P (=T.sub.L +T.sub.R) distributed to the rear wheels is decreased to avoid an increase in travel resistance. Thus, it is possible to prevent the occurrence of problems such as a deterioration of specific fuel consumption, an abnormal sound generated in a drive system and an increase in the load of the drive system due to an increase in travel resistance during turning of the vehicle.
摘要:
An electromagnetic clutch having a solenoid coil (80), a coil housing (81) disposed surrounding the solenoid coil (80), an armature plate (82) disposed facing the side of the coil housing, and a wet-type multi-plate clutch mechanism, the armature plate being linked to the clutch housing (52). The current flowing to the solenoid coil (80) is controlled so as to control the clamping of the armature plate (82) to the coil housing (81), and the clamping force acting on the armature plate is used made to act on the clutch mechanism via a ball cam mechanism (65). A first rotational backlash amount BLm occurring between the rotation input member and the rotation output member in a rotation transmission system in which the clutch mechanism is interposed in an engaged state, and a second rotational backlash amount BLp occurring between the rotation input member and the rotation output member in a rotation transmission system in which the cam mechanism is interposed in a state in which the cam mechanism is fixed and the armature plate is clamped to the coil housing, are set such that BLm>BLp.
摘要:
A starting assistance device for a vehicle has an electric motor and a dog clutch which is switched on at the time of starting of the vehicle to thereby transmit a torque to idler wheels. A sensor is provided to detect the switching on and switching off of the dog clutch. In case the switching off of the dog clutch is not detected when the rotational speeds of the idler wheels have exceeded a predetermined value after the starting of the vehicle, the electric motor is driven in such a direction of rotation so as to cancel the torque which operates on the dog clutch due to the frictional force in the electric motor.
摘要:
A power transmitting system for a four-wheel drive vehicle includes a first hydraulic pump driven interlockingly with the rotation of front wheels, a second hydraulic pump driven interlockingly with the rotation of rear wheels, and a hydraulic clutch for connecting the front wheels and rear wheels. The hydraulic clutch is adapted to be brought into an engaged state by an increase in oil pressure based on the difference between the amount of oil discharged from one of the hydraulic pumps and the amount of oil drawn into the other hydraulic pump. The hydraulic clutch, first hydraulic pump and second hydraulic pump are arranged in that sequence from the front toward rear of the vehicle on an axis extending longitudinally of the vehicle to maximize the air cooling effect on the hydraulic clutch and minimize the length of oil passages between the two hydraulic pumps.
摘要:
To ensure the benefits of four-wheel drive when the vehicle is accelerating or when the front wheels are slipping, and to eliminate the disadvantage of undesirably transmitting the braking force to the rear wheels when the vehicle is decelerating or when a braking action is applied to the vehicle, the front wheels and the rear wheels are coupled with each other when the rotational speed of the front wheels is higher than that of the rear wheels, but this coupling is disconnected when the rotational speeds of the front and rear wheels are substantially identical or when the rotational speed of the rear wheels is higher than that of the front wheels. To achieve this irrespective of whether the vehicle is moving forward or rearward, the power transmission system comprises a first pump coupled with the front wheels, a second pump coupled with the rear wheels, communication passages connecting these pumps in series with the inlet of one of them being connected to the outlet of the other, a fluid pressure actuated clutch interposed between the front and rear wheels, and a switching valve for appropriately actuating the clutch according to the difference in the outputs and/or inputs of these pumps.
摘要:
To the end of eliminating the problems arising from substantially rigid connection between a front wheel set and a rear wheel set in a four-wheel drive vehicle, there is provided a power transmission system in which a speed-dependent power transmission device is provided between the front wheel set and the rear wheel set so that both the wheel sets are substantially rigidly connected to each other in a low speed range and rotational power is transmitted only from the front wheel set to the rear wheel set in a high speed range. The power transmission device of this kind can be conveniently formed by a pair of one-way clutch elements which are connected between an input member and an output member in a mutually parallel relationship; one of the one-way clutch elements transmitting power from the input member to the output member in both the high and the low speed range while the other one-way clutch element transmits power only from the output member to the input member in the low speed range but does not transmit power in either direction in the high speed range. This speed-dependency can be accomplished by using one-way clutch sprag elements each having a gravitational center offset from its center of rolling motion for wedging between the input member and the output member.
摘要:
In a front and rear wheel steering device for a vehicle in which the steering angle ratio of the rear wheels relative to the front wheels is variable according to the vehicle speed, by accounting for the magnitude of vehicle acceleration in determining the steering angle ratio of the rear wheels by using a mathematical function in the form of f(u) - g(u')where u is a vehicle speed and u' is a change rate of the vehicle speed, it is possible to reduce the slip angle of the vehicle to zero irrespective of the vehicle speed and the vehicle acceleration and the phase delay of the lateral response of the vehicle can be reduced, whereby the driveability of the vehicle is substantially improved and, thus, driving a car can be made easier, safer and less tiring.
摘要:
In a front and rear wheel steering device contive for vehicle in which the steering angle ratio of the rear wheels relative to the front wheels is variable according to the vehicle speed, provision of a manual selection means for fixing the steering angle ratio to certain fixed values which may be either positive or negative can greatly improve the maneuverability of the vehicle in both high speed and low speed ranges. However, inadvertent manual selection of the steering angle ratio is not desirable since it may cause a sudden change in the steering angle of the rear wheels. Therefore, this invention provides means for preventing the manual selection of the steering angle ratio when it is not proper. This means may be an active prohibition control of manual steering angle ratio selection means, an alarm to warn the driver or a vehicle speed control which limits the vehicle speed. The situations in which the manual selection of the steering angle ratio is not proper may be determined from such factors as vehicle acceleration, transmission shift position, steering rate and so on.