Abstract: In a reduction-transmission mechanism, an input member is arranged at such a position that a size obtained by adding a fitting clearance formed between a ball bearing and an outer periphery of an eccentric portion, a fitting clearance formed between the ball bearing and an inner periphery of the input member, which defines a center hole, and a radial internal clearance of the ball bearing is smaller than a size obtained by adding a fitting clearance formed between an outer periphery of each of a plurality of output members and a corresponding one of needle roller bearings, a fitting clearance formed between each of the needle roller bearings and an inner periphery of the input member, which defines a corresponding one of a plurality of pin insertion holes, and a radial internal clearance of each of the needle roller bearings.

Abstract: In a driving force transmission apparatus, an oil inlet portion for introducing hydraulic fluid from one of spaces to the other one of the spaces is formed, and an apparatus case has an oil outlet portion for delivering the hydraulic fluid from the other one of the spaces to an outside of the other one of the spaces with an oil delivery capacity lower than an oil introducing capacity of the oil inlet portion. A pressure regulation valve for bringing the oil inlet portion into an open state upon reception of hydraulic pressure higher than or equal to a predetermined pressure from hydraulic fluid is arranged at the oil inlet portion.

Abstract: A speed reduction mechanism includes: a speed reduction unit that includes an input member formed of an external gear that makes circular motion about a rotation axis with an eccentric amount, and a rotation force applying member formed of an internal gear that is in mesh with the input member; and a lubricating oil supply unit that supplies lubricating oil to a bearing of the speed reduction unit. The lubricating oil supply unit includes an oil tank arranged outside of the rotation force applying member, an oil delivery passage that delivers the lubricating oil to the oil tank, and a first oil introduction passage that introduces the lubricating oil from the oil tank to the bearing. The lubricating oil is delivered to the oil delivery passage through pumping action of the input member based on the circular motion.

Abstract: A motor driving force transmission system includes an electric motor that generates motor torque for actuating a differential mechanism portion and outputs the motor torque, and that has a motor shaft with eccentric portions, and a bearing mechanism including a ball bearing interposed between one-side axial end portion of a housing and one-side axial end portion of a differential case, a ball bearing interposed between the other-side axial end portion of the differential case and one-side axial end portion of the motor shaft, and a ball bearing interposed between the other-side axial end portion of the housing and the other-side axial end portion of the motor shaft. An axial load is applied to the ball bearings of the bearing mechanism by a spring.

Abstract: A motor driving force transmission device including a speed reduction and transmission mechanism which transmits a motor driving force to a rear differential, a first electric motor that is connected to the rear differential via the speed reduction and transmission mechanism and which produces a first motor driving force, a second electric motor that is connected to the first electric motor and the speed reduction and transmission mechanism and which produces a second motor driving force, and an ECU. The ECU outputs a control signal to drive both the first electric motor and the second electric motor when a driving torque required for the rear differential is equal to or larger than a predetermined torque, and outputs a control signal to drive alternately the first electric motor and the second electric motor when the driving torque required for the rear differential is smaller than the predetermined torque.

Abstract: A motor driving force transmission device includes electric motors which produce motor driving force with which a rear differential is operated and a speed reduction and transmission mechanism which reduces the speed of the motor driving force of the electric motors and transmits it to the rear differential. The speed reduction and transmission mechanism has eccentric cams which rotate as the electric motors are driven, transmission members which rotate as the eccentric cams rotate, and is disposed on an outer circumference of the rear differential.

Abstract: In a driving force transmission apparatus, an oil inlet portion for introducing hydraulic fluid from one of spaces to the other one of the spaces is formed, and an apparatus case has an oil outlet portion for delivering the hydraulic fluid from the other one of the spaces to an outside of the other one of the spaces with an oil delivery capacity lower than an oil introducing capacity of the oil inlet portion. A pressure regulation valve for bringing the oil inlet portion into an open state upon reception of hydraulic pressure higher than or equal to a predetermined pressure from hydraulic fluid is arranged at the oil inlet portion.

Abstract: In a reduction-transmission mechanism, an input member is arranged at such a position that a size obtained by adding a fitting clearance formed between a ball bearing and an outer periphery of an eccentric portion, a fitting clearance formed between the ball bearing and an inner periphery of the input member, which defines a center hole, and a radial internal clearance of the ball bearing is smaller than a size obtained by adding a fitting clearance formed between an outer periphery of each of a plurality of output members and a corresponding one of needle roller bearings, a fitting clearance formed between each of the needle roller bearings and an inner periphery of the input member, which defines a corresponding one of a plurality of pin insertion holes, and a radial internal clearance of each of the needle roller bearings.

Abstract: A driving force transmission apparatus includes a cam mechanism that converts motor torque from an electric motor into first cam thrust force and second cam thrust force. The cam mechanism includes: a cam member that rotates upon reception of the motor torque from an electric motor; a rolling member that rolls on the cam member; and a retainer that outputs the first cam thrust force and the second cam thrust force toward a multiple disk clutch as the rolling member rolls. The rotation of the retainer around a rotation axis is restricted, and the retainer moves in a direction of the rotation axis while retaining the rolling member such that the rolling member is rollable.

Abstract: A reduction-transmission mechanism includes: an input member formed of an external gear that makes circular motion with an eccentric amount; a rotation force applying member formed of an internal gear that is in mesh with the input member; and output members that receive and output rotation force applied to the input member by the rotation force applying member, and that are passed through the respective pin insertion holes. Each of the output members is provided with a needle roller bearing at a portion that is able to contact an inner periphery, which defines a corresponding one of the through-holes, and the input member has third oil supply passages that extend from the center hole to the pin insertion holes, and lubricating oil is supplied to the needle roller bearings through the third oil supply passages by centrifugal force generated in accordance with rotation of the motor shaft.

Abstract: A speed reduction mechanism includes: a speed reduction unit that includes an input member formed of an external gear that makes circular motion about a rotation axis with an eccentric amount, and a rotation force applying member formed of an internal gear that is in mesh with the input member; and a lubricating oil supply unit that supplies lubricating oil to a bearing of the speed reduction unit. The lubricating oil supply unit includes an oil tank arranged outside of the rotation force applying member, an oil delivery passage that delivers the lubricating oil to the oil tank, and a first oil introduction passage that introduces the lubricating oil from the oil tank to the bearing. The lubricating oil is delivered to the oil delivery passage through pumping action of the input member based on the circular motion.