Honda Motor Co., Ltd.

Honda Giken Kogyo Kabushiki Kaisha

Ryuichi Murakami

Kentaro Arai

Yusuke Sakaguchi

Yasunori Arai

Kenichiro Hayashi

Tetsuro Hamada

Susumu Takahashi

Nobutaka Yamaguchi

Katsuhiro Kitamura

Kazuhiro Wada

Yasuhiko Sugo

Jiro Hara

Kouji Ono

Nor Hairuddin

Naoharu Takatani

Tomoaki Kasuya

Takatani Naoharu

Provided is a driving force control device for a four-wheel-drive vehicle that can evade an occurrence of excessive understeer and oversteer in situations unintended by the driver, by appropriately controlling driving forces to be distributed to sub-drive wheels. The driving force distribution device of the four-wheeled vehicle controls driving force to be distributed to the rear wheels (Wr, Wr) by the clutch () for front-and-rear torque distribution so that the wheels (Wf, Wf) are main drive wheels and the rear wheels (Wr, Wr) are sub-drive wheels. The driving force distribution device is adapted to perform control to restrict the upper limit of the four-wheel drive torque based upon an estimated driving force and steering angle of the vehicle, when calculating four-wheel drive torque to be distributed to the rear wheels (Wr, Wr) by the driving force distribution device ().

Driving force control device for four-wheel-drive vehicle

In a hydraulic controller of driving force distribution device, including: a hydraulic circuit composed of an oil pump for supplying hydraulic fluid to a piston chamber of a clutch (or a driving force distribution device), an opening and closing valve installed in an oil passage between a check valve and the piston chamber, and an accumulator communicating to the piston chamber; control is performed so that the piston chamber reaches a target hydraulic pressure based on the 1st characteristic by closing the opening and closing valve and driving the oil pump at the time of pressurizing the piston chamber; and control is performed so that the piston chamber reaches a target hydraulic pressure based on the 2nd characteristic by prohibiting the driving of the oil pump along with opening the opening and closing valve.

Hydraulic controller of driving force distribution device

A driving force control device for a four-wheel-drive vehicle performs, by controlling the driving force that is allocated to the rear wheels by a front and rear torque allocation clutch that is arranged between a propeller shaft and a rear diff, the control of setting front wheels as primary drive wheels and rear wheels as auxiliary drive wheels. A control is performed to disable the allocation of driving force to the rear wheels by disengaging the front and rear torque allocation clutch, when the state that the difference in wheel speed between the left and right rear wheels is equal to or more than 80 km continues for 0.1 sec or longer in the state that the vehicle body speed is equal to or less than 120 km.

A torque cam mechanism comprises first and second cam members disposed relatively rotatably around a common axis and cam balls adapted to fit in first and second cam grooves formed, respectively, in confronting surfaces of the first and second cam members. The depth of the first cam grooves is made larger than the radius of the cam balls, whereas the depth of the second cam grooves is made smaller than the radius of the cam balls, whereby even though a centrifugal force is applied to the cam balls which rotate together with the first and second cam members, the generation of thrust forces for separating the confronting surfaces of the first and second cam members can be suppressed by receiving the centrifugal force so applied to the cam balls by the first cam grooves which are deeper.

Torque cam mechanism and power transmission system for four-wheel drive vehicle

A four-wheel drive vehicle having a first hydraulic pump operated in operative association with the rotation of front wheels, and a second hydraulic pump operated in operative association with the rotation of rear wheels, such that a difference in rotational speed is produced between the front and rear wheels, a multi-plate clutch is brought into its engaged state by a hydraulic pressure generated by the hydraulic pumps, whereby the mode of the vehicle is shifted into a four-wheel drive mode. A torque cam mechanism is disposed between a clutch piston and clutch plates, so that when the difference in rotational speed is produced between the front and rear wheels, the torque cam mechanism produces an axial thrust force immediately to promptly bring the multi-plate clutch into its engaged state. The engagement of the multi-plate clutch is achieved with a sufficient engagement force by the hydraulic pressure thereafter produced by the hydraulic pump.

Power transmitting system for four-wheel drive vehicle

An electromagnetic clutch having a solenoid coil ( ), a coil housing ( ) disposed surrounding the solenoid coil ( ), an armature plate ( ) disposed facing the side of the coil housing, and a clutch mechanism. The current flowing to the solenoid coil ( ) is controlled so as to control the clamping of the armature plate ( ) to the coil housing ( ), and the clamping force acting on the armature plate is used to control the engagement of the clutch mechanism. There is also a lubricating oil supply channel ( ) for supplying lubricating oil from the inside in the radial direction into a gap between the coil housing and the armature plate, and oil reservoir holding lubricating oil to be supplied into the gap is formed around the inner periphery of the portion where the coil housing faces the armature plate.

Lubrication structure of electro-magnetic clutch

Growing community of inventors

Wako, Japan

Ryuichi Murakami