WO2005030518A1

WO2005030518A1 - Electrically-driven wheel-driving device

Info

Publication number: WO2005030518A1
Application number: PCT/JP2004/012049
Authority: WO
Inventors: Kenichi Iwamoto; Takashi Nozaki; Tokumasa Nakamura; Tatsuya Yamasaki
Original assignee: Ntn Corporation
Priority date: 2003-09-29
Filing date: 2004-08-23
Publication date: 2005-04-07
Also published as: JP2005104216A

Abstract

[PROBLEMS] An electrically-driven wheel-driving device where durability of rolling bearings is increased, that is reduced in size and in weight, and that improves traveling performance of a vehicle. [MEANS FOR SOLVING PROBLEMS] An electric wheel-driving device has a bearing device (2) for a wheel, a planetary speed reducer (3), a driving section (6), and a rotation-transmitting device (5) for connecting a rotating shaft (4) and an input shaft (21) installed coaxial with the rotating shaft (4) via serrations (27b). The planetary speed reducer (3) has a sun roller (17), planetary rollers (15) rolling along the inner peripheral surface of an external member (9), and carrier pins (14) for rotatably supporting the planetary rollers (15) at a hub wheel (7). The rotation-transmitting device (5) is constituted of a two-way clutch (25) and an electromagnetic clutch (26) having an electromagnet for causing an electromagnetic force that adheres an armature (35) and a rotor (37) to act. A phase of a retainer (31) relative to an interior member (30) is changed by action of the electromagnetic force, a roller (32) is engaged with the interior member (30) and an outer ring (27), and a rotating shaft (4) and an input shaft (21) are connected and cutoff in both rotating directions.

Description

Specification

Electric wheel drive

Technical field

The present invention is used for vehicles such as electric vehicles, golf carts, and forklifts.

The present invention relates to an electric wheel drive device including a wheel and an electric motor. Background art

[0002] An electric wheel drive device has been proposed to increase the driving efficiency when driving wheels with an electric motor. The electric wheel drive device is used for driving wheels of a vehicle such as an electric vehicle, and is directly driven by an electric motor. The wheel is configured to be rotationally driven. However, this type of electric wheel drive requires a large output torque for the electric motor, so a large electric motor must be used. In this case, not only the cost is increased but also the weight is increased, and it becomes difficult to sufficiently secure the traveling performance of the vehicle.

[0003] On the other hand, a reduction gear in which an electric motor and a planetary gear reducer are arranged in a space inside the wheel, and the rotation output of the electric motor is transmitted to the wheel via the planetary gear reducer. A motorized wheel drive (wheel motor) has already been proposed.

[0004] However, a planetary gear reducer is employed as a speed reducer, and an output shaft for transmitting the rotation output of the rotor of the electric motor to the wheels via the planetary gear reducer is in the axial direction of the electric wheel drive device. Once divided, the output is taken out with the shaft center aligned, which makes the structure complicated and difficult to assemble.In addition, the support span of the output shaft must be shortened, resulting in low support strength against falling wheels. There was a point.

[0005] As a solution to these problems, an electric wheel drive device as shown in Fig. 7 is known. This electric wheel drive device 51 has a built-in electric motor 54 and a gear reducer 55 inside a wheel 53 on which a tire 52 is mounted, and rotates the wheel 53 by the rotation output of the electric motor 54. It is composed and laid.

[0006] The electric motor 54 includes a stator 57 fixed to the case 56 side disposed inside the wheels 53, a rotor 58 disposed opposite the stator 57, and a rotation output of the rotor 58. An output shaft 59 that transmits the wheel 53 via a gear reducer 55. Stator 57 The rotor 58 is fixed to the case 56 while being sandwiched between the covers 60 and 61 to form an electric motor 54.

[0007] The output shaft 59 has a mounting flange 62 formed at one end 59a thereof, and fixes the wheel 53 via a hub bolt 63. One end 59a of the output shaft 59 rotates through a shaft bearing hole 56b of the case 56 via a rolling bearing 64, and the other end 59b rotates through a central recess 60a of the outer cover 60 via a rolling bearing 65. It is freely supported.

[0008] The gear reducer 55 accommodated in the case 56 includes a plurality of gears 55a, 55b, 55c, and 55d. The first gear 55a is integrally formed concentrically with the end of the rotor 58. The second and third gears 55b and 55c are fixed to the same support shaft 66 and rotate integrally with each other, and the second gear 55b and the first gear 55a are combined. One end 66a of the support shaft 66 is rotatably supported by a recess 61a of the inner cover 61 via a rolling bearing 67, and the other end 66b is rotatably supported by a recess 56a of the case 56 via a rolling bearing 68. ing. The fourth gear 55d is fixed to the output shaft 59, and engages with the third gear 55c.

[0009] With such a configuration, the output shaft 59 of the electric motor 54 passes through the rotation center hole of the fourth gear 55d, which is the final stage of the gear reducer 55, and the shaft hole 58a of the rotor 58. In this state, it is rotatably supported on both ends of the case 56, so the components of the gear reducer 55, the inner cover 61, the components of the electric motor 54, and the outer cover 60 are fitted in order based on the output shaft 59. And can be easily assembled. In addition, since the output shaft 59 is supported at substantially both ends of the electric wheel drive device 51 as a whole, its support span can be made as long as possible, so that sufficient support strength against falling down of the wheel 53 can be obtained. Can be obtained.

Patent Document 1: JP-A-7-81436

Disclosure of the invention

Problems to be solved by the invention

[0010] In such a conventional electric wheel drive device 51, this kind of gear reducer 55 can easily assemble various components, but on the other hand, the electric motor 54 disposed inside the wheel 53 can be reduced in size. In order to obtain high rotational output with this electric motor 54, space is inevitably increased, so the installation space for the rolling bearings 64 and 65 that support the output shaft 59 is limited. Is done. Therefore, the load capacity with respect to the falling of the wheel 53, that is, the moment load, is insufficient, and improvement in durability of the rolling bearings 64, 65 has been demanded.

[0011] The present invention aims to solve such a conventional problem and to provide an electric wheel drive device that improves the durability of rolling bearings, reduces the size and weight of the device, and improves the running performance of a vehicle. Target.

Means for solving the problem

[0012] An invention according to claim 1 of the present invention that achieves the above object is a wheel bearing device, a planetary reduction gear mounted on the wheel bearing device, and driving the planetary reduction device. An electric motor, wherein the wheel bearing device comprises: a hub wheel having a wheel mounting flange at one end; and an inner ring having at least one of a plurality of rows of inner rolling surfaces formed on an outer periphery thereof. An outer member having an inner periphery formed with a double row of outer rolling surfaces facing the inner rolling surface, and a double row of rolling elements rotatably accommodated between the two rolling surfaces. The planetary gear reducer includes an input element rotatably inserted into the hub wheel, a fixed element disposed on the inner peripheral side of the outer member, and a fixed element disposed between the fixed element and the input element. And a plurality of planetary elements arranged on the hub wheel and an output element for rotatably supporting the planetary elements with respect to the hub wheel. With the door, adopting the configuration which is adapted to drive the wheels via the wheel hub.

[0013] Thus, the fixing element of the planetary reduction gear is disposed on the inner peripheral side of the outer member of the wheel bearing device, the output element is fixed to the hub wheel, and the planetary element is rotatable by the output element. In addition to the support, the planetary element is arranged between the input element and the outer member, so that sufficient space for the bearing part can be secured, the durability of the bearing part can be improved against moment loads, and the overall size of the device can be reduced. The weight can be reduced and the unsprung load of the vehicle can be reduced, so that the riding comfort and running stability can be dramatically improved.

[0014] Further, the invention according to claim 2 of the present invention provides a wheel bearing device, a planetary reduction gear mounted on the wheel bearing device, and a driving unit that drives a rotating shaft of the planetary reduction device. And a rotation transmission device for connecting the rotation shaft and an input shaft of a drive unit disposed coaxially so as to be able to transmit torque, wherein the wheel bearing device has a wheel mounting flange at one end. A wheel, an inner ring having at least one of a plurality of inner rolling surfaces formed on an outer periphery thereof, and a plurality of outer rolling surfaces facing the inner rolling surface formed on an inner periphery. Outside And a double row rolling element rotatably accommodated between the two rolling surfaces, wherein the planetary reduction gear comprises: a rotating shaft rotatably inserted in the hub wheel; and a rotating shaft. An input element, a fixed element disposed on the inner peripheral side of the outer member, a plurality of planetary elements disposed between the fixed element and the input element, An output element rotatably supported on the hub wheel, wherein the rotation transmitting device coaxially and rotatably fits the input shaft and the outer ring so as to be capable of transmitting torque to the input shaft. A plurality of cam surfaces are provided on one of the outer periphery of the combined inner member and the inner periphery of the outer ring, and a cylindrical surface is provided on the other. A wedge-shaped space is formed between both surfaces, and a cage is interposed in the wedge-shaped space. An engaging element is incorporated in a plurality of pockets formed in the retainer, and the inner member or By changing the phase of the retainer with respect to the wheel, a wedge-engaged state is formed between the engagement element, the inner member, and the outer ring, so that the rotational shaft and the input shaft can be connected and disconnected in both rotational directions. The input shaft is rotated by the electric motor of the drive unit, and the rotation is rotated via the rotation transmission device.The rotation of the rotation shaft is controlled via the input element. The rotation of the planetary element is transmitted to the wheels via the hub wheel.

[0015] As described above, the rotation transmission device is disposed between the planetary reduction gear and the drive unit, and the two rotation shafts and the input shaft are connected and disconnected in both rotation directions, so that the power is transmitted. Transmission and cutoff can be selectively switched, and the clutch mechanism can be operated according to the speed difference between the wheels to automatically switch between transmission and cutoff of the driving force, absorbing the rotational difference between the wheels. It can have the differential limiting function together with the function. In addition, by controlling the disk brake and the power transmission device, it is possible to regenerate electric power using an electric motor. In addition, by disengaging the clutch mechanism, the dragging portion of the drive system is reduced, which contributes to improving the fuel efficiency of the vehicle by reducing the rolling resistance.

[0016] Preferably, as in the invention according to claim 3, the rotation transmitting device rotatably fits the input shaft and the outer ring coaxially and fits the input shaft so as to be capable of transmitting torque. A plurality of cam surfaces are provided on the outer periphery of the inner member thus formed, a cylindrical surface is provided on the inner periphery of the outer ring, a wedge-shaped space is formed between both surfaces, and a retainer is interposed in the wedge-shaped space. Rollers are incorporated into a plurality of pockets formed in the container, and the pockets are held against the inner member. By changing the phase of the retainer, the roller is engaged with the inner member and the outer ring, and the rotation shaft and the input shaft are connected and disconnected in both rotational directions. Small and light weight can be achieved.

[0017] The invention according to claim 4 provides an armature provided rotatably relative to the input shaft, a rotor provided non-rotatable relative to the rotation shaft, and an armature. And an electromagnet for applying an electromagnetic force to attract the rotor and the rotor, and the phase of the retainer may be changed with respect to the inner member or the outer ring by the action of the electromagnetic force.

[0018] Further, the invention according to claim 5 is characterized in that a plurality of rectangular openings are formed on the hub wheel and the inner ring fitted to the hub wheel in a circumferentially equidistant manner. A recess is formed at the center in the circumferential direction of the planetary gear, and a carrier pin serving as an output element of the planetary reduction gear is fixed to the recess. The planetary element is rotatably supported on the carrier pin. Space can be sufficiently secured, the durability of the bearing portion can be improved with respect to the moment load, and the size and weight of the device can be further reduced.

[0019] Further, according to the invention as set forth in claim 6, since the two widths are formed at both ends of the carrier pin and the two widths are fitted into the recesses, the carrier can be surely formed with a simple configuration. The pin can be fixed to the hub wheel, and the planetary roller can be easily assembled.

[0020] Further, in the invention according to claim 7, the planetary element is disposed between the double-row outer rolling surfaces formed on the inner periphery of the outer member, so that the planetary element is not biased. The load can be suppressed, and uneven wear and the like of the planetary element can be suppressed.

[0021] In the invention according to claim 8, rolling bearings are provided on both sides of the input element, and the input element is rotatably supported on the hub wheel via these rolling bearings. As a result, an uneven load on the input element can be suppressed, and a force S for preventing uneven wear of the input element can be achieved.

[0022] Further, according to the invention as set forth in claim 9, in the planetary reduction device, the planetary reduction device is provided at one end of the rotation shaft rotatably inserted in the hub wheel. A sun roller, a plurality of planetary rollers disposed between an outer peripheral surface of the sun roller and an inner peripheral surface of the outer member, and a carrier pin rotatably supporting the planetary rollers with respect to the hub wheel. Since the power transmission between the sun roller and the planetary roller and between the planetary roller and the outer member is performed by frictional transmission, noise and vibration generated during power transmission should be suppressed as much as possible. Can be.

[0023] Further, according to the invention as set forth in claim 10, in the planetary reduction gear, a rotation shaft rotatably mounted on the hub wheel, a sun gear provided at one end of the rotation shaft, A plurality of planetary gears combined with the external teeth of the sun gear and the internal teeth formed on the inner peripheral surface of the outer member; and a carrier pin rotatably supporting the planetary gears with respect to the hub wheel. As a result, power can be transmitted efficiently without sliding contact, and lubrication can be performed with the lubricating grease sealed in the bearing.

[0024] Preferably, if the fixing element is formed integrally with the outer member as in the invention according to claim 11, the entire device can be lightweight and compact, and the number of parts can be reduced. In both cases, the assembly work can be simplified.

The invention's effect

[0025] An electric wheel drive device according to the present invention includes a wheel bearing device, a planetary reduction gear mounted on the wheel bearing device, and an electric motor that drives the planetary reduction device. The bearing device includes a hub wheel having a wheel mounting flange at one end, an inner ring having at least one of a plurality of rows of inner rolling surfaces formed on an outer circumference, and the inner rolling surface on an inner circumference. An outer member having a double row of outer rolling surfaces opposed to the outer race member, and a double row of rolling elements rotatably housed between the two rolling surfaces, wherein the planetary reduction gear comprises: An input element rotatably inserted into the wheel, a fixed element disposed on the inner peripheral side of the outer member, and a plurality of planetary elements disposed between the fixed element and the input element. And an output element for rotatably supporting these planetary elements with respect to the hub wheel. Since the wheels are driven through the wheels, sufficient space for the bearings can be secured, the durability of the bearings can be improved against moment loads, and the overall size and weight of the equipment can be reduced. By reducing the unsprung load, the riding comfort and running stability can be dramatically improved.

[0026] Further, an electric wheel drive device according to the present invention includes a wheel bearing device, a planetary reduction gear mounted on the wheel bearing device, and a drive unit that drives a rotating shaft of the planetary reduction device. Previous A rotation transmission device for connecting the rotation shaft and an input shaft of a drive unit arranged coaxially so as to be able to transmit torque, wherein the wheel bearing device has a hub wheel having a wheel mounting flange at one end; An inner ring having at least one of a plurality of rows of inner rolling surfaces formed on an outer periphery thereof, and an outer ring having a plurality of rows of outer rolling surfaces opposed to the inner rolling surface formed on an inner circumference thereof. The planetary reduction gear comprises a rotating shaft rotatably inserted in the hub wheel; and a rotating shaft rotatably inserted in the hub wheel. An input element provided on a shaft, a fixed element disposed on the inner peripheral side of the outer member, a plurality of planetary elements disposed between the fixed element and the input element, An output element rotatably supporting the hub wheel with respect to the hub wheel. The outer ring is rotatably fitted coaxially, and a plurality of cam surfaces are provided on one of the outer periphery of the inner member or the inner periphery of the outer ring fitted with the input shaft so as to transmit torque, and the other is a cylindrical surface. A wedge-shaped space is formed between both surfaces, a retainer is interposed in the wedge-shaped space, and engaging elements are incorporated into a plurality of pockets formed in the retainer, with respect to the inner member or the outer ring. By changing the phase of the retainer, a wedge-engaged state is formed between the engagement element, the inner member, and the outer ring, so that the rotation shaft and the input shaft can be coupled and separated in both rotational directions. The input shaft is rotated by the electric motor of the drive unit, and the rotation is rotated through the rotation transmission device. The rotation of the rotation shaft is converted into the planetary planet through the input element. To the element and the rotation of this planetary element By transmitting the power to the wheels via the hub wheels, transmission and disconnection of the power can be selectively switched, and the clutch mechanism is operated according to the speed difference of the wheels to automatically transmit the driving force. The switching can be switched, and it can have the function of absorbing the rotational difference between the wheels and the function of limiting the differential. In addition, by controlling the disk brake and the power transmission device, it is possible to regenerate electric power using an electric motor. In addition, by disengaging the clutch mechanism, the drag portion of the drive system is reduced, which contributes to the improvement of vehicle fuel efficiency due to the reduction of rolling force and resistance.

BEST MODE FOR CARRYING OUT THE INVENTION

A bearing device for a wheel, a planetary reducer mounted on the bearing device for a wheel, a drive unit for driving a rotating shaft of the planetary speed reducer, and a driving unit disposed coaxially with the rotating shaft. A rotation transmission device for connecting the power shaft to the power shaft so as to be capable of transmitting a torque, wherein the wheel bearing device has a wheel mounting flange integrally at one end, and a cylindrical small diameter extending axially from the wheel mounting flange. A hub wheel having a stepped portion, a pair of inner rings which are externally fitted to the small-diameter stepped portion of the hub wheel and have an inner rolling surface formed on the outer periphery, and an inner circumference opposed to the inner rolling surface. An outer member having a double-row outer rolling surface formed thereon; and a double-row rolling element rotatably accommodated between the two rolling surfaces, wherein the planetary reduction gear is mounted on the hub wheel. A rotatable rotating shaft, a sun roller provided at one end of the rotating shaft, and a roller arranged to roll along the outer peripheral surface of the sun roller and the inner peripheral surface of the outer member. And a carrier roller for rotatably supporting the planetary rollers with respect to the hub wheel. Wherein the rotation transmission device is configured such that the input shaft and the outer ring are rotatably fitted coaxially, and a plurality of cam surfaces are provided on an outer periphery of an inner member fitted to the input shaft so as to transmit torque. In addition, a cylindrical surface is provided on the inner periphery of the outer ring, a wedge-shaped space is formed between both surfaces, a retainer is interposed in the wedge-shaped space, and rollers are incorporated into a plurality of pockets formed in the retainer. Rarely, an armature provided rotatably relative to the input shaft, a rotor provided non-rotatable relative to the rotation shaft, and an electromagnet for applying an electromagnetic force to attract the armature and the rotor. And by changing the phase of the retainer with respect to the inner member by the action of the electromagnetic force, the roller is engaged with the inner member and the outer ring, and the rotation shaft is connected to the input shaft. Connecting and disconnecting shafts in both rotation directions The input shaft is rotated by the electric motor of the drive unit, and the rotation is rotated through the rotation transmission device. The rotation of the rotation shaft is controlled by the sun roller. The rotation of the planetary roller is transmitted to the wheels via the hub wheel.

Example 1

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a longitudinal sectional view showing a first embodiment of an electric wheel drive device according to the present invention,

2 is a view taken in the direction of the arrow A in FIG. 1, and FIG. 3 is a cross-sectional view taken along the line III-III in FIG.

[0029] The electric wheel drive device 1 is provided coaxially with a wheel bearing device 2, a planetary reduction gear 3 mounted on the wheel bearing device 2, and a rotating shaft 4 of the planetary reduction device 3. Input shaft 2 The main configuration is a rotation transmission device 5 incorporated in 1 and a drive unit 6 for driving the input shaft 21. In the following description, the side closer to the outside of the vehicle will be referred to as the outboard side (left side in the drawing), and the side closer to the center will be referred to as the inboard side (right side in the drawing) when assembled to the vehicle.

[0030] The wheel bearing device 2 is referred to as a second generation that supports a driving wheel (not shown). The wheel bearing device 2 integrally includes a wheel mounting flange 7a for mounting a wheel at an end on the outboard side, and a cylindrical small-diameter stepped portion 7b extending from the wheel mounting flange 7a to the inboard side. A pair of inner rings 8, 8 formed on the formed hub wheel 7, a small-diameter stepped portion 7 b of the hub wheel 7, and having inner rolling surfaces 8 a, 8 a formed on the outer periphery, and a pair of inner rings 8. An outer member 9 integrally having a vehicle body mounting flange 9b fixed to the vehicle body on the outer periphery, and having a plurality of rows of outer rolling surfaces 9a, 9a formed on the inner periphery facing the inner rolling surfaces 8a, 8a. And a double-row rolling element (ball) 10 rotatably accommodated between these rolling surfaces 8a and 9a, and a bearing retainer 11 for holding these rolling elements 10 at equal circumferences. Have.

[0031] On the outer peripheral surface of the hub wheel 7, a hardened layer is formed with a surface hardness in the range of 54 to 64 HRC from the base of the wheel mounting flange 7a to the small diameter stepped portion 7b. As the heat treatment, quenching by high-frequency induction heating, which can perform local heating and relatively easily set the depth of the hardened layer, is preferable. Here, the end on the inboard side is unhardened with a surface hardness of 25 HRC or less, and is plastically deformed radially outward to form a caulked portion 7c. The inner ring 8 fitted to the small-diameter stepped portion 7b of the hub wheel 7 is fixed in the axial direction by the caulking portion 7c.

[0032] In the present embodiment, the so-called self-resetting, which allows the internal clearance of the bearing to be a negative clearance, improves the bearing stiffness, and maintains the preload by fixing the inner ring 8 in the axial direction by the caulking portion 7c. The structure is adopted. Therefore, it is not necessary to control the amount of preload by firmly tightening the bearing portion with a nut or the like as in the related art, so that the incorporation into a vehicle can be simplified. Sealing devices (not shown) are attached to both ends of the outer member 9 to prevent leakage of lubricating grease sealed in the bearing and to prevent dust and muddy water from entering the bearing from outside. . Here, a double-row angular contact ball bearing using balls for the rolling elements has been described as an example, but the present invention is not limited to this, and a double-row tapered roller bearing using tapered rollers may be used.

FIG. 2 is a partial cross-sectional view taken along the arrow A in FIG. 1. A plurality of rectangular openings 12 are formed in the small-diameter stepped portion 7b of the hub wheel 7 at equal circumferential intervals. Of the position corresponding to this opening 12 The butting portions 8b, 8b of the wheels 8, 8 are also formed with an opening 13 composed of a pair of recesses 13a, 13a. Concave portions 12a and 13b are formed in the central portions in the circumferential direction of the openings 12 and 13, respectively, and a carrier pin (output element) 14 of a planetary reduction gear 3, which will be described later, is fixed, and as shown in FIG. A roller (planetary element) 15 is rotatably supported.

[0034] Both ends of the carrier pin 14 are formed to have a two-sided width 14a, and are fitted into the recesses 12a and 13b so as to be non-rotatably supported. The planetary roller 15 is rotatably supported on the carrier pin 14 via a rolling bearing 16. The planetary roller 15 rolls along the inner peripheral surface 9c of the outer member 9 and the outer peripheral surface 17a of the sun roller (input element) 17, as shown in FIG. Although the small-diameter stepped portion 7b of the hub wheel 7 and the butting portions 8b, 8b of the pair of inner rings 8, 8 are formed with the openings 12, 13 in this example, the present invention is not limited to this. A rectangular opening may be formed on the inner ring, and the other inner ring may be abutted against this inner ring, or an inner rolling surface and a small-diameter step may be formed directly on the outer periphery of the hub wheel, and this step may be formed. The other inner ring may be abutted, or a first or third generation structure may be applied.

In FIG. 1, the planetary reduction gear 3 includes a sun roller 17 integrally formed at an end of the rotating shaft 4 on the outboard side, and four planetary rollers 15 that perform planetary motion around the sun roller 17. A carrier pin 14 for rotatably supporting the planetary rollers 15 with respect to the hub wheel 7 and the inner ring 8 is provided. The rotating shaft 4 is rotatably supported on the hub wheel 7 by rolling bearings 18, 18 provided at both ends of the sun roller 17.

The rotation of the rotating shaft 4 is transmitted to the planetary roller 15 via the sun roller 17, and the rotation of the planetary roller 15 is transmitted to the wheels via the hub wheel (carrier) 7. Therefore, the power transmission between the sun roller 17 and the planetary roller 15 and between the planetary roller 15 and the outer member (fixing element) 9 is performed by friction transmission (traction drive), so that noise generated during power transmission is generated. And vibration can be suppressed as much as possible.

[0037] The reduction ratio of the planetary reduction gear 3 can be appropriately adjusted by changing the ratio of the outer diameter of the planetary roller 15 to the inner diameter of the outer member 9. For example, an electric wheel drive for an electric vehicle is used. When applied to gearboxes, the reduction ratio can be set in the range of 3-9. Furthermore, if a reduction ratio of this level can be obtained, it is possible to sufficiently cope with this by reducing the outer diameter of the end portion of the rotating shaft 4, that is, the sun roller 17, and the reduction can be achieved by increasing the reduction ratio. The speed machine does not increase in size. Further, planetary rollers 15 are disposed between the double rows of outer rolling surfaces 9a, 9a formed on the inner periphery of the outer member 9 in the wheel bearing device 2, and the sun rollers 17 are rolled in pairs. Since it is rotatably supported via bearings 18, 18, uneven load on the planetary roller 15 and sun roller 17 can be suppressed, and uneven wear of the planetary roller 15 and sun roller 17 can be suppressed. can do.

The driving unit 6 is fixed to the housing 19, faces the stator 20 around which the electromagnetic coil 20 a is wound, through a predetermined air gap, and is mounted on the outer periphery of the input shaft 21. An electric motor 23 including a motor rotor 22 and a pair of rolling bearings 24 that rotatably support the input shaft 21 with respect to the housing 19 are provided. When the electric motor 23 is energized, the input shaft 21 rotates, and the rotation of the input shaft 21 is transmitted to the planetary reduction gear 3 via the rotation transmission device 5.

[0039] The rotation transmission device 5 includes a two-way clutch 25 and an electromagnetic clutch 26. The two-way clutch 25 rotatably fits the input shaft 21 and the outer ring 27 coaxially via a rolling bearing 28, A plurality of cam surfaces 30a are provided on the outer periphery of the inner member 30 fitted to the input shaft 21 through the serration (or spline) 29, and a cylindrical surface 27a is provided on the inner periphery of the outer ring 27, and a wedge-shaped surface is formed between both surfaces. A space is formed and a retainer 31 is interposed in the wedge-shaped space, and a roller 32 as an engaging element is incorporated in a plurality of pockets 31a formed in the retainer 31. A switch spring 33 for urging and supporting the retainer 31 to a neutral position where the roller 32 is not engaged with the cylindrical surface 27a is locked between the retainer 31 and the inner member 30 having the cam surface 30a. .

The retainer 31 is supported by the inner member 30 via a support plate 34 so as to be rotatable and immovable in the axial direction. One end of the retainer 31 is inserted into a locking hole 35a of an armature 35 made of a disk-shaped magnetic material, and the armature 35 is supported so as not to rotate relatively and to be movable in the axial direction. The amateur 35 has its inner peripheral surface guided by the input shaft 21, and is movable in the axial direction and the rotation direction with respect to the input shaft 21.

A rotor 37 made of a magnetic material having a U-shaped cross section is fixed to the outer ring 27 via a rotor guide 36 made of a non-magnetic material such as an aluminum alloy. A rolling bearing 38 is fitted on the inner periphery of the rotor 37, and rotatably supports the outer ring 27 and the input shaft 21 via the rotor 37 and the rotor guide 36. [0042] The rotor 37 has a built-in electromagnetic coil 39 for causing the amateur 35 and the rotor 37 to flank each other via a predetermined axial clearance, and for bringing the armature 35 and the rotor 37 into pressure contact with each other. Further, a separation spring 40 made of a wave spring or the like is mounted between the armature 35 and the rotor 37, and separates the armature 35 and the rotor 37 in the axial direction when the current of the electromagnetic coil 39 is off.

Next, the operation of the rotation transmitting device 5 will be described in detail. When the current is off, the retainer 31 and the roller 32 are urged to the neutral position of the cam surface 30a provided on the inner member 30 by the switch spring 33, so that the inner member 30 and the outer ring 27 idle. Although it is possible, when the electromagnetic coil 39 is energized, the armature 35 connected to the retainer 31 is attracted to the rotor 37 integrated with the outer ring 27. The friction tonnole between the armature 35 and the rotor 37 pressed by such suction acts between the retainer 31 and the outer ring 27 via the rotor guide 36, and the inner member 30 and the outer ring 27 rotate relatively. Then, the friction torque is piled on the spring force of the switch spring 33 to rotate the retainer 31 and the roller 32 together with the outer ring 27. As a result, the roller 32 moves from the neutral position of the cam surface 30a to the engagement position of the wedge-shaped space, from the input shaft 21 to the serration 29, the inner member 30, the roller 32, the outer ring 27, and the serration spline. The rotation torque is transmitted to the rotation shaft 15 through the shaft.

In the present embodiment, since the planetary rollers 15 constituting the planetary reduction gear 3 are incorporated between the two rolling surfaces 8a, 9a of the wheel bearing device 2, a sufficient space for the bearing portion can be secured, and It is possible to improve the durability of the bearing portion even with respect to one load. The rotation transmission device 5 described above is disposed between the drive unit 6 and the planetary reduction gear 3, and changes the phase of the retainer 31 with respect to the inner member 30 so that the roller 32 serving as an engagement element is formed. A wedge engagement state is formed between the inner shaft member 30 and the outer ring 27, and coupling and disconnection of the two rotating shafts 15 and the input shaft 21 in both rotational directions can selectively transmit and cut off power. You can switch. Therefore, the clutch mechanism can be operated according to the speed difference between the four wheels, and the transmission / disconnection of the driving force can be switched automatically. It can also have functions and enables a compact four-wheel drive mechanism. In addition, by controlling the disk brake (not shown) and the power transmission device, electric power regeneration using the electric motor 23 becomes possible. In addition, by disengaging the clutch mechanism, the drag This contributes to improving vehicle fuel efficiency by reducing rolling resistance. Example 2

FIG. 4 is a longitudinal sectional view showing a second embodiment of the electric wheel drive device according to the present invention. The second embodiment differs from the above-described first embodiment only in the configuration of the planetary reduction gear, and the same reference numerals are given to the same parts having the same components or the same functions, and detailed description thereof will be given. Omitted.

The planetary reducer 41 includes a sun gear 42 integrally formed at the end of the rotating shaft 4 on the outboard side, four planetary gears 43 that perform planetary motion around the sun gear 42, and these planetary gears. 43 is provided with a carrier pin 14 that rotatably supports the hub wheel 7 and the inner ring 8. The planetary gear 43 constituting the speed reducer 41 is rotatably supported on the carrier pin 14 via a rolling bearing 16. The outer teeth 43a of the planet gear 43 rotate in accordance with the inner teeth 9d formed on the inner peripheral surface of the outer member 9 and the outer teeth 42a of the sun gear 42. The rotating shaft 4 is rotatably supported on the hub wheel 7 by rolling bearings 18 provided at both ends of the sun gear 42.

[0047] The rotation of the rotating shaft 4 is transmitted to the planetary gear 43 via the sun gear 42, and the rotation of the planetary gear 43 is transmitted to the wheels via the hub wheel 7. Therefore, the power transmission between the sun gear 42 and the planetary gear 43 and between the planetary gear 43 and the outer member (outer sun gear) 9 is performed by the gear transmission mechanism, so that power can be transmitted efficiently without sliding contact. At the same time, it can be lubricated with the lubricating grease sealed in the bearing.

Example 3

FIG. 5 is a longitudinal sectional view showing a third embodiment of the electric wheel drive device according to the present invention. In the third embodiment, the rotary shaft and the input shaft of the drive unit in the first embodiment described above are integrated, and the same parts having the same parts or the same functions are denoted by the same reference numerals. The detailed description is omitted.

[0049] The electric wheel drive device is provided at one end of a wheel bearing device 2, a planetary reduction gear 3 mounted on the wheel bearing device 2, and a rotating shaft 44 of the planetary reduction device 3. And a drive unit 6 for driving the rotating shaft 44.

[0050] The planetary reduction gear 3 is provided with a sun roller 17 integrally formed at the end of the rotating shaft 44 on the outboard side. And four planetary rollers 15 that perform planetary motion around the sun roller 17, and a carrier pin 14 that rotatably supports the planetary roller 15 with respect to the hub wheel 7 and the inner ring 8. Further, the rotating shaft 4 is rotatably supported on the hub wheel 7 by rolling bearings 18 provided at both ends of the sun roller 17.

When the electric motor 23 of the drive unit 6 is energized, the rotation shaft 44 rotates, and the rotation of the rotation shaft 44 is transmitted to the planetary roller 15 via the sun roller 17, and the rotation of the planetary roller 15 is The speed is reduced via the wheel 7 and transmitted to the wheels.

With the electric wheel drive device of the present embodiment having such a configuration, it is possible to significantly reduce the size and weight of the vehicle, to improve the fuel efficiency of the vehicle, and to detect the vehicle speed to control each wheel. It controls the current of the left and right electric motors 23 in combination with the ABS (anti-lock brake system) that controls the appropriate rotation of the wheels. It is.

Example 4

FIG. 6 is a longitudinal sectional view showing a fourth embodiment of the electric wheel drive device according to the present invention. The fourth embodiment differs from the above-described third embodiment only in the configuration of the planetary reduction gear. The same reference numerals are given to the same parts having the same parts or the same functions, and the detailed description thereof will be described. Omitted.

The planetary reducer 41 includes a sun gear 42 integrally formed at the end of the rotating shaft 4 on the outboard side, four planetary gears 43 that perform planetary motion around the sun gear 42, A carrier pin 14 is provided for rotatably supporting the gear 43 with respect to the hub wheel 7 and the inner ring 8. The planet gear 43 constituting the planetary reduction gear 41 is rotatably supported on the carrier pin 14 via a rolling bearing 16. The outer teeth 43a of the planet gear 43 rotate in accordance with the inner teeth 9d formed on the inner peripheral surface of the outer member 9 and the outer teeth 42a of the sun gear 42. The rotating shaft 4 is rotatably supported on the hub wheel 7 by rolling bearings 18 provided at both ends of the sun gear 42.

The rotation of the rotating shaft 44 is transmitted to the planetary gear 43 via the sun gear 42 as in the third embodiment described above, and the rotation of the planetary gear 43 is transmitted to the wheels via the hub wheel 7. Is done. Therefore, it is possible to achieve a lightweight and compact design and improve the fuel efficiency of the vehicle. In addition, since the power transmission between the sun gear 42 and the planetary gear 43 and between the planetary gear 43 and the outer member 9 is performed by the gear transmission mechanism, power can be transmitted efficiently without sliding contact.

The embodiments of the present invention have been described above. However, the present invention is not limited to these embodiments, but is merely an example, and does not depart from the gist of the present invention. Of course, the present invention can be embodied in various forms. Including all changes within.

Industrial applicability

[0057] The electric wheel drive device according to the present invention includes four-wheeled vehicles such as fuel cell vehicles and electric vehicles, two-wheeled vehicles, golf carts, three- or four-wheeled carts for the elderly and disabled, It can be applied when various types of vehicles such as hand-held unicycles or four-wheeled vehicles used in the transportation industry are to be electrically driven or when auxiliary power is applied by electric power.

Brief Description of Drawings

FIG. 1 is a longitudinal sectional view showing a first embodiment of an electric wheel drive device according to the present invention.

FIG. 2 is a partial cross-sectional view of FIG.

FIG. 3 is a transverse sectional view taken along the line III-III in FIG. 1.

FIG. 4 is a longitudinal sectional view showing a second embodiment of the electric wheel drive device according to the present invention.

FIG. 5 is a longitudinal sectional view showing a third embodiment of the electric wheel drive device according to the present invention.

FIG. 6 is a longitudinal sectional view showing a fourth embodiment of the electric wheel drive device according to the present invention.

FIG. 7 is a longitudinal sectional view showing a conventional electric wheel drive device.

Explanation of symbols

[0059] 1 Electric wheel drive device

2 Wheel bearing device

3, 41 planetary reducer

4, 44 rotation axis

5 Rotation transmission device

6 Drive Hub wheel a Wheel mounting flange b Small diameter step c Caulking section

Inner ring

a Inner rolling surface b Butt joint

Outer member b Body mounting flange c Inner peripheral surface d Internal teeth

0 rolling element

1 Bearing retainer 2. 13, 13a opening

2a, 13b recess

4 Carrier pin 4a Width across flats

5 Planetary rollers 6. 18, 24, 28, 38 ··· Rolling force S-bearing 7 Sun roller 7a Outer surface

9 Housing

Stator a, 39 electromagnetic coil 1 input shaft

Motor rotor Electric motor 2-way clutch Electromagnetic clutch Outer ring

a cylindrical surface

b, 29 Serration

Inner member

a cam surface

Cage

a pocket

roller

Switching spring support plate amateur a locking hole

Rotor guide Rotor

Release spring

Sun gear

a, 43a External teeth

Planetary gear

Electric wheel drive tire

Wheel

Electric motor Gear reducer a Little brother 1 difficult wheel b 2nd gear c 3rd gear d 4th gear Case a, 60a, 61a Concave b 揷 Through hole

Stator rotor Output shaft a, 66a One end b, 66b The other end. 61 Cover b Recess

Mounting flange Hub bonoreto. 65, 67, 68 Rolling bearing Support shaft

Claims

The scope of the claims

[1] A wheel bearing device, a planetary reducer mounted on the wheel bearing device, and an electric motor for driving the planetary gear reducer,

The wheel bearing device includes a hub wheel having a wheel mounting flange at one end, an inner ring having at least one of a plurality of rows of inner rolling surfaces formed on an outer circumference, and the inner rolling having an inner circumference. An outer member having a double-row outer rolling surface opposed to the running surface, and a double-row rolling element rotatably accommodated between the two rolling surfaces;

The planetary reduction gear includes an input element rotatably inserted into the hub wheel, a fixed element disposed on an inner peripheral side of the outer member, and a fixed element disposed between the fixed element and the input element. A plurality of arranged planetary elements, and an output element that rotatably supports the planetary elements with respect to the hub wheel;

An electric wheel drive device, wherein the wheels are driven via the hub wheel.

[2] A wheel bearing device, a planetary reducer mounted on the wheel bearing device, a drive unit for driving a rotating shaft of the planetary speed reducer, and a drive arranged coaxially with the rotating shaft. A rotation transmitting device for connecting the input shaft of the section to the input shaft so as to transmit torque.

The planetary reduction gear includes a rotation shaft rotatably inserted in the hub wheel, an input element provided on the rotation shaft, and a fixed element disposed on an inner peripheral side of the outer member. A plurality of planetary elements disposed between a fixed element and the input element, and an output element for rotatably supporting the planetary elements with respect to the hub wheel;

The rotation transmission device is configured such that the input shaft and the outer ring are rotatably fitted coaxially, and one of an outer periphery of an inner member fitted to the input shaft so as to be capable of transmitting torque and an inner periphery of the outer ring. A plurality of cam surfaces and a cylindrical surface on the other side, a wedge-shaped space is formed between the two surfaces, a retainer is interposed in the wedge-shaped space, and an engaging element is incorporated into a plurality of pockets formed in the retainer. By changing the phase of the cage with respect to the inner member or the outer ring, A wedge engagement state is formed between the engagement element, the inner member, and the outer ring, so that the rotation shaft and the input shaft are connected and disconnected in both rotational directions. The input shaft is rotated by an electric motor, the rotation is rotated via the rotation transmission device, and the rotation of the rotation shaft is transmitted to the planetary planetary element via the input element. An electric wheel drive device, wherein rotation of an element is transmitted to a wheel via the hub wheel.

[3] The rotation transmission device may be configured such that the input shaft and the outer ring are rotatably fitted coaxially, and a plurality of cam surfaces are provided on an outer periphery of an inner member fitted to the input shaft so as to be capable of transmitting torque. A cylindrical surface is provided on the inner periphery of the outer ring, a wedge-shaped space is formed between both surfaces, a retainer is interposed in the wedge-shaped space, and rollers are incorporated in a plurality of pockets formed in the retainer. By changing the phase of the retainer with respect to the inner member, the roller is engaged with the inner member and the outer ring, and the coupling and disengagement of the rotating shaft and the input shaft in both rotational directions are performed. 3. The electric wheel driving device according to claim 2, wherein the driving is performed.

[4] An armature provided rotatably relative to the input shaft, a rotor provided non-rotatable relative to the rotation shaft, and an electromagnet for applying an electromagnetic force to attract the armature and the rotor. 4. The electric wheel drive device according to claim 2, further comprising: changing a phase of the retainer with respect to the inner member or the outer ring by an action of the electromagnetic force.

[5] A plurality of rectangular openings are formed in the hub wheel and the inner ring fitted to the hub wheel in a circumferentially equidistant manner, and a recess is formed in the center in the circumferential direction of each of these openings. The carrier pin as an output element of the planetary reduction gear is fixed to the recess, and the planetary element is rotatably supported by the carrier pin. Electric wheel drive.

6. The electric wheel drive device according to claim 5, wherein two widths are formed at both ends of the carrier pin, and the two widths are fitted into the recesses.

7. The electric wheel drive device according to claim 1, wherein the planetary element is arranged between double rows of outer rolling surfaces formed on an inner periphery of the outer member.

[8] Rolling bearings are provided on both sides of the input element, and the rolling bearings are provided through these rolling bearings. The electric wheel drive device according to any one of claims 1 to 7, wherein the input element is rotatably supported on the hub wheel.

[9] The planetary speed reducer includes a rotating shaft rotatably inserted into the hub wheel, a sun roller provided at one end of the rotating shaft, an outer peripheral surface of the sun roller, and the outer member. The electric motor according to any one of claims 1 to 8, further comprising a plurality of planetary rollers arranged between the inner peripheral surface and a carrier pin that rotatably supports the planetary rollers with respect to the hub wheel. Type wheel drive.

[10] The planetary reduction gear includes a rotation shaft rotatably inserted into the hub wheel, a sun gear provided at one end of the rotation shaft, and outer teeth of the sun gear and the outer member. 9. The vehicle according to claim 1, further comprising: a plurality of planetary gears combined with internal teeth formed on an inner peripheral surface; and a carrier pin rotatably supporting the planetary gears with respect to the hub wheel. The electric wheel drive.

11. The electric wheel drive device according to claim 1, wherein the fixing element is formed integrally with the outer member.