Abstract: A four-wheel drive vehicle includes: a driving force transmission system which transmits torque of a drive source to front wheels and rear wheels via gear mechanisms; a clutch provided in the driving force transmission system and capable of controlling an amount of the torque transmitted to the rear wheels; and a pressing mechanism which presses the clutch by transforming a part of the torque transmitted to the rear wheels into axial thrust. In the driving force transmission system, gear ratios of the gear mechanisms are set such that a direction of a differential rotation between a drive shaft connected to an input side of the clutch and a drive shaft connected to an output side of the clutch is not reversed even when a steered angle of the front wheels changes to a maximum value while the four-wheel drive vehicle is traveling forwards.

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: An electromagnetic clutch includes: a first cam member having a first cam surface; a second cam member having a second cam surface facing the first cam surface; a coned disc spring that urges the second cam member such that the first and second cam surfaces are separated from each other; a clutch plate that contacts the second cam member due to urging force of the urging member, and generates friction force between the clutch plate and the second cam member; and an electromagnetic coil that generates magnetic force with which the second cam member is separated from the clutch plate against the urging force of the urging member. The first cam surface and the second cam surface generate thrust force by which the second cam member is pushed against the friction member, through relative rotation between the first cam member and the second cam member due to the friction force.

Abstract: A cage of each of ball bearings arranged on respective outer peripheries of eccentric portions of a motor shaft has an annular base portion interposed between an inner ring and an outer ring and a plurality of partition wall portions for forming pockets together with the base portion. In a first ball bearing, part of the base portion protrudes axially outward from the inner raceway and forms an oil receiving portion that receives lubricating oil from the second rolling bearing side, at a portion around the rotation axis and axially outward of the first rolling bearing.

Abstract: A driving force transmission apparatus includes: a first cam mechanism that converts rotational force from a housing into first cam thrust force used as clutch force of a main clutch when the first cam mechanism is actuated through clutch action of a pilot clutch; and a second cam mechanism that is actuated prior to conversion of the rotational force into the first cam thrust force by the first cam mechanism, and that generates second cam thrust force for reducing an interval between clutch plates of the main clutch. The second cam mechanism includes an input cam member that rotates upon receiving rotational force used as actuating force of the input cam member from a cam actuating driving source, and an output cam member that generates the second cam thrust force between the output cam member and the input cam member and outputs the second cam thrust force.

Abstract: An electromagnetic clutch includes a rotating member; an electromagnetic coil that is arranged on a rotational axis of the rotating member and generates electro-magnetic force; an output mechanism that has an armature to which return force in a direction away from the electromagnetic coil is applied by a return spring; a cam mechanism that is juxtaposed along the rotational axis to the output mechanism, and has a control cam that is unable to rotate relative to the rotating member, and a cam follower that is able to roll between the control cam and the armature; and a relative rotation restricting device that is arranged on an axis of the cam mechanism, and that is configured to restrict relative rotation between the armature and the control cam when the electromagnetic coil is in a de-energized state.

Abstract: A differential (1) for a vehicle includes a differential case (2), side gears (5L, 5R) rotatably accommodated in the differential case (2), pinion gears (3, 4) engaged with the side gears (5L, 5R), and pinion gear shaft (50) inserted through the pinion gears (3, 4) to be supported by the differential case (2), in which the differential case (2) has pinion gear supporting portions (10, 11) for rotatably supporting the pinion gears (3, 4), respectively, the pinion gear shaft (50) has pinion gear supporting surfaces (50A, 50B) for rotatably supporting the pinion gears (3, 4), respectively, and the pinion gear supporting surfaces (50A, 50B) are disposed on a side of an axis line of rotation of the differential case (2) with respect to the pinion gear supporting portions (10, 11).

Abstract: It is an object of the present invention to provide a differential case for a vehicle and a differential device for a vehicle restricting change and movement of an intermeshing of a pair of side gears and a pair of pinion gears to achieve stable differential restriction force. The differential case or the differential device for the vehicle comprises a case body 50 accommodating a pair of side gears 5R, 5L and a pinion gear 3 or 4 engaging in mesh with the side gears 5R, 5L, and a pinion gear supporter 53 accommodated in said case body 50 and having a pinion gear supporting portion 56 or 57 to install said pinion gear 3 or 4 in recess space 60, 61 of said pinion gear supporter 53 and to support slidably an outer peripheral surface of said pinion gear 3 or 4 for rotation of said pinion gear 3 or 4.

Abstract: A driving force transmission apparatus includes: a driving force transmission shaft receiving driving force of a driving source from a rotating member and transmitting the driving force from a main driving wheel side to an auxiliary driving wheel side; a first driving force interruption unit connects/disconnects the driving force transmission shaft to/from the rotating member; a second driving force interruption unit connects/disconnects the driving force transmission shaft to/from at least one of two auxiliary driving wheels so that transmitted torque is variable; and a control unit controls connection and disconnection of the first and second driving force interruption units. The control unit causes the second driving force interruption unit to connect/disconnect the driving force transmission shaft to/from the at least one of the auxiliary driving wheels before causing the first driving force interruption unit to connect/disconnect the driving force transmission shaft to/from the rotating member.

Abstract: It is an object of the present invention to provide a differential case for a vehicle and a differential device for a vehicle restricting change and movement of an intermeshing of a pair of side gears and a pair of pinion gears to achieve stable differential restriction force. The differential case or the differential device for the vehicle comprises a case body 50 accommodating a pair of side gears 5R, 5L and a pinion gear 3 or 4 engaging in mesh with the side gears 5R, 5L, and a pinion gear supporter 53 accommodated in said case body 50 and having a pinion gear supporting portion 56 or 57 to install said pinion gear 3 or 4 in recess space 60, 61 of said pinion gear supporter 53 and to support slidably an outer peripheral surface of said pinion gear 3 or 4 for rotation of said pinion gear 3 or 4.

Abstract: A differential (1) for a vehicle includes a differential case (2), side gears (5L, 5R) rotatably accommodated in the differential case (2), pinion gears (3, 4) engaged with the side gears (5L, 5R), and pinion gear shaft (50) inserted through the pinion gears (3, 4) to be supported by the differential case (2), in which the differential case (2) has pinion gear supporting portions (10, 11) for rotatably supporting the pinion gears (3, 4), respectively, the pinion gear shaft (50) has pinion gear supporting surfaces (50A, 50B) for rotatably supporting the pinion gears (3, 4), respectively, and the pinion gear supporting surfaces (50A, 50B) are disposed on a side of an axis line of rotation of the differential case (2) with respect to the pinion gear supporting portions (10, 11).

Abstract: A vehicle drive device 20 is composed of an electric motor 20a, a differential gear 20d for distributing and transmitting the drive power from the electric motor 20a to right and left drive wheels, and a clutch 20c for making intermittent the coupling capable of transmitting the drive power between the differential gear 20d side and the electric motor 20a side. The clutch 20c is of the type having a self-locking function and is arranged coaxially of the differential gear 20d at one side of the differential gear 20d.

Abstract: Disclosed are a combination of a drive power transmission device and a differential gear, which combination is decreased in the number of parts, increased in rigidity and reduced in weight as well as in manufacturing cost, and a method of manufacturing the combination. A gear shaft which is provided with a drive gear for a differential gear is rotatably supported in a differential case. The differential case is provided with a partition wall portion which extends outwardly from an opening end portion thereof from which the gear shaft protrudes. A clutch case is secured to the circumferential edge portion of the partition wall portion thereby to define a housing chamber. A housing with a clutch receiving chamber formed therein is rotatably supported on the clutch case inside the housing chamber.

Abstract: In a power transfer device composed of a bottomed cylindrical housing 20a rotatably mounted on an inner shaft 20b and a main friction clutch 20c and a pilot friction clutch 30a coaxially assembled within a cylindrical space between the housing 20a and inner shaft 20b through a cam mechanism 30b, the thickness of a shim plate 39b for adjustment of a clearance between an inner clutch plate or outer clutch plate located at one side of an electromagnetic clutch 30a used as the pilot friction clutch and an inner end surface of an end wall block 21b threaded into an opening end portion of the housing 20a is determined on a basis of a clearance L1 between one side surface of a thrust bearing 39a assembled with an input cam member 35 of the cam mechanism 30b and an inner clutch plate or outer clutch plate located at one side of the electromagnetic clutch 30a.

Abstract: A vehicle drive device 20 is composed of an electric motor 20a, a differential gear 20d for distributing and transmitting the drive power from the electric motor 20a to right and left drive wheels, and a clutch 20c for making intermittent the coupling capable of transmitting the drive power between the differential gear 20d side and the electric motor 20a side. The clutch 20c is of the type having a self-locking function and is arranged coaxially of the differential gear 20d at one side of the differential gear 20d.

Abstract: Disclosed are a combination of a drive power transmission device and a differential gear, which combination is decreased in the number of parts, increased in rigidity and reduced in weight as well as in manufacturing cost, and a method of manufacturing the combination. A gear shaft which is provided with a drive gear for a differential gear is rotatably supported in a differential case. The differential case is provided with a partition wall portion which extends outwardly from an opening end portion thereof from which the gear shaft protrudes. A clutch case is secured to the circumferential edge portion of the partition wall portion thereby to define a housing chamber. A housing with a clutch receiving chamber formed therein is rotatably supported on the clutch case inside the housing chamber.

Abstract: In a power transfer device composed of a bottomed cylindrical housing 20a rotatably mounted on an inner shaft 20b and a main friction clutch 20c and a pilot friction clutch 30a coaxially assembled within a cylindrical space between the housing 20a and inner shaft 20b through a cam mechanism 30b, the thickness of a shim plate 39b for adjustment of a clearance between an inner clutch plate or outer clutch plate located at one side of an electromagnetic clutch 30a used as the pilot friction clutch and an inner end surface of an end wall block 21b threaded into an opening end portion of the housing 20a is determined on a basis of a clearance L1 between one side surface of a thrust bearing 39a assembled with an input cam member 35 of the cam mechanism 30b and an inner clutch plate or outer clutch plate located at one side of the electromagnetic clutch 30a.

Abstract: A power transfer device including a main clutch, a cam mechanism and an electromagnetic pilot clutch mechanism coaxially assembled within a cylindrical space between an external cylindrical rotary member and an internal rotary member, wherein an electromagnetic coil of the pilot clutch mechanism is applied with an electric current to produce pilot torque, the cam mechanism is applied with the pilot torque to produce thrust force in an axial direction, and the main clutch is engaged by the thrust force applied from the cam mechanism to effect drive connection between the rotary members. In the power transfer device, residual thrust force of the cam mechanism is electrically or mechanically decreased at an instance when differential rotation of the rotary members is reversed.

Abstract: A driving force transmission device transmits driving force between an outer case made of magnetic substance and inner shaft. A main clutch mechanism, an electromagnetic type pilot clutch mechanism and cam mechanism are arranged between the outer case and inner shaft. The main clutch mechanism transmits driving force between the outer case and inner shaft. The pilot clutch mechanism controls operation of the main clutch mechanism and comprises an electromagnet, an armature and a friction clutch. The cam mechanism amplifies output of the pilot clutch mechanism and transmits amplified output to the main clutch mechanism. The driving force transmission device further comprises a first regulation member and/or a second regulating member. The first regulating member adjusts a clearance between the cam mechanism and the armature to be more than a predetermined distance. The second regulating member adjusts an axial position of the friction clutch.

Abstract: A driving force transmission system comprising: a coupling case and a shaft arranged rotatably relative to each other; a pilot clutch and a main clutch for controlling a torque transmission between the coupling case and the shaft; an electromagnet for controlling the actions of the pilot clutch and the main clutch; and oil retaining the functions of the pilot clutch and the main clutch. This system further comprises a coupling case, a shaft, a rotor, and X-ring and an O-ring isolating a coupling oil chamber, in which the pilot clutch and the main clutch are arranged, liquid-tight from the surrounding space.