JP2005231428A - Electric wheel driving device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric wheel driving device capable of enhancing durability of a wheel bearing device, reducing the size and the weight of the device, and improving the vehicular traveling performance. <P>SOLUTION: The electric wheel driving device comprises two planetary reduction gears 2 and 2' which are mounted on a wheel bearing device 1 and connected to each other via a connection shaft 6, and a driving unit 4 having an electric motor 22 mounted on a rotary member 20. The first planetary reduction gear 2 comprises a sun roller 17 fixed to a rotary shaft 3 of the rotary member 20, a plurality of planetary rollers 15 rolling along an outer circumferential surface 17a thereof and an inner circumferential surface 8d of an outer member 8, and a carrier pin 14 to support these rollers by the connection shaft 6. The second planetary reduction gear 2' comprises a sun roller 17' fixed to the connection shaft 6, a plurality of planetary rollers 15' rolling along an outer circumferential surface 17a' thereof and an inner circumferential surface 8c of the outer member 8, and a carrier pin 14' to support these rollers by a hub wheel 5, and a disk brake 24 is integrally mounted on the rotary member 20. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an electric wheel drive device that is used in a vehicle such as an electric vehicle, a golf cart, or a forklift, and in which a wheel bearing device and an electric motor are integrated.

  The electric wheel drive device is proposed to increase the driving efficiency when the wheels are driven by an electric motor, and is used for driving wheels of an electric vehicle or the like, and directly rotates and drives the wheels by the electric motor. It is configured as follows. However, since this type of electric wheel drive device requires a large output torque for the electric motor, a large electric motor must be used. This not only increases the cost but also increases the weight, making it difficult to ensure sufficient vehicle performance.

  On the other hand, an electric motor and a planetary gear speed reducer are arranged in the inner space portion of the wheel, and the rotation output of the electric motor is transmitted to the wheel via the planetary gear speed reducer. A drive device (wheel motor) has already been proposed.

  However, a planetary gear reducer is adopted as the reducer, and the output shaft that transmits the rotation output of the rotor of the electric motor to the wheels via the planetary gear reducer is once divided in the axial direction of the electric wheel drive device. Since the output will be taken out later by aligning the shaft center, the configuration is complicated and difficult to assemble, and the support span of the output shaft must be shortened, so the support strength against the falling of the wheel is low. It was.

  As a solution to these problems, an electric wheel drive device as shown in FIG. 17 is known. The electric wheel drive device 101 includes an electric motor 104 and a gear reducer 105 inside a wheel 103 on which a tire 102 is mounted, and is configured to rotationally drive the wheel 103 by the rotation output of the electric motor 104. Has been.

  The electric motor 104 includes a stator 107 fixed to the case 106 disposed inside the wheel 103, a rotor 108 disposed opposite to the inside of the stator 107, and the rotational output of the rotor 108 as a gear reducer 105. And an output shaft 109 that is transmitted to the wheel 103 via the wheel. The stator 107 and the rotor 108 are fixed to the case 106 side while being sandwiched between the covers 110 and 111 to constitute the electric motor 104.

  The output shaft 109 has a mounting flange 112 integrally formed at one end 109 a thereof, and a wheel 103 is fixed via a hub bolt 113. One end 109a of the output shaft 109 is rotatable in a shaft insertion hole 106b of the case 106 via a rolling bearing 114, and the other end 109b is rotatable in a central recess 110a of the outer cover 110 via a rolling bearing 115. It is supported.

  The gear reducer 105 accommodated in the case 106 is composed of a plurality of gears 105a, 105b, 105c and 105d. The first gear 105 a is integrally formed concentrically with the end portion of the rotor 108. The second and third gears 105b and 105c are fixed to the same support shaft 116 and rotate integrally with each other, and the second gear 105b and the first gear 105a are engaged with each other. One end 116a of the support shaft 116 is rotatably supported by the recess 111a of the inner cover 111 via the rolling bearing 117, and the other end 116b is rotatably supported by the recess 106a of the case 106 via the rolling bearing 118. Yes. The fourth gear 105d is fixed to the output shaft 109 and meshes with the third gear 105c.

With such a configuration, the output shaft 109 of the electric motor 104 passes through the rotation center hole of the fourth gear 105d, which is the final stage of the gear reducer 105, and the shaft insertion hole 108a of the rotor 108. Since both ends are rotatably supported, the components of the gear reducer 105, the inner cover 111, the components of the electric motor 104, and the outer cover 110 are sequentially fitted and assembled with reference to the output shaft 109. be able to. Further, since the output shaft 109 is supported by substantially both ends of the electric wheel drive device 101 as a whole, the support span can be taken as long as possible, so that sufficient support strength against the falling of the wheel 103 is obtained. be able to.
JP-A-7-81436

  In such a conventional electric wheel drive device 101, this type of gear reducer 105 can easily assemble various components, while miniaturizing the electric motor 104 disposed inside the wheel 103. In order to obtain a high rotational output by the electric motor 104, a space is inevitably increased, and thus the installation space for the rolling bearings 114 and 115 for supporting the output shaft 109 is limited. Therefore, the wheel 103 has fallen, that is, the load capacity with respect to the moment load is insufficient, and improvement has been demanded in terms of improving the durability of the rolling bearings 114 and 115.

  It is an object of the present invention to provide an electric wheel drive device that solves these conventional problems, improves the durability of the wheel bearing device, reduces the size and weight of the device, and improves the running performance of the vehicle. To do.

  In order to achieve such an object, the invention according to claim 1 of the present invention includes a wheel bearing device having a double row bearing, and a second bearing device mounted on the wheel bearing device and connected via a connecting shaft. 1 and a second planetary speed reducer, and a drive unit having an electric motor for driving the first planetary speed reducer, and the rotation of the electric motor is controlled by the first planetary speed reducer and the second planetary speed reducer. A configuration is adopted in which the power is transmitted to the hub wheel constituting the wheel bearing device by decelerating in two stages by a machine, and the braking device is integrally mounted on the rotating member.

  As described above, the rotation of the electric motor is decelerated in two stages by the first planetary speed reducer and the second planetary speed reducer to transmit the power to the hub wheel constituting the wheel bearing device and to constitute the drive unit. Since the braking device is integrally mounted on the rotating member, sufficient space for the bearing portion can be ensured, and the weight and size can be reduced. In addition, the cost can be reduced by sharing the parts, and the braking action can be applied before the vehicle is decelerated, so that the braking torque can be reduced and a lightweight and compact braking device in the radial direction can be provided.

  The invention according to claim 2 of the present invention includes a wheel bearing device having a double row bearing, and the first and second bearing devices mounted on the wheel bearing device and connected via a connecting shaft. A planetary speed reducer and a drive unit having an electric motor for driving the first planetary speed reducer, wherein the wheel bearing device has a wheel mounting flange at one end and a small-diameter stepped portion formed on the outer periphery. An inner member that includes a hub ring and an inner ring that is externally fitted to the small-diameter step portion of the hub ring and has at least one inner rolling surface formed on the outer periphery. An outer member in which an outer rolling surface of a double row opposite to the inner rolling surface is formed on an inner periphery, and a double row accommodated in a freely rolling manner between the both rolling surfaces. The first planetary speed reducer includes an input element coupled to a rotating shaft so as not to be relatively rotatable, and And a plurality of planetary elements disposed between the fixed element and the input element, and an output for rotatably supporting the planetary elements with respect to the connecting shaft. The second planetary speed reducer includes an input element coupled to the coupling shaft so as not to rotate relative thereto, a fixed element disposed on an inner peripheral side of the outer member, and the fixed element A plurality of planetary elements disposed between the input elements and an output element that rotatably supports the planetary elements with respect to the hub wheel, and the drive unit constitutes the electric motor, A stator portion integrally disposed on the outer member, a rotor portion facing the stator portion via a predetermined air gap, and the rotor portion are fixed and rotatable with respect to the outer member. A rotating member that is supported and integrally has the rotating shaft, The rotation of the serial electric motor, said first and second through the planetary reduction gear is transmitted to the wheel hub drives the wheel braking device to the rotating member is attached integrally.

  Adopting such a configuration, it is possible to secure a sufficient space for the bearing part, to improve the durability by increasing the bearing strength against moment load, and to reduce the overall weight and size of the device. Can be achieved. Further, the durability of the bearing portion can be improved with respect to the moment load applied to the device, and the unsprung weight of the vehicle can be reduced, so that the ride comfort and running stability can be improved.

  In the invention according to claim 3, since the planetary element of the second planetary speed reducer is disposed between the double row outer rolling surfaces formed on the inner periphery of the outer member, Uneven load on the planetary element can be suppressed, and uneven wear of the planetary element can be suppressed.

  Preferably, if the braking device is a parking brake as in the invention described in claim 4, the parts can be shared, and the parking brake that has been conventionally disposed on the wheel side is moved to the inboard side. Therefore, the degree of freedom in layout can be improved by securing the space around the wheel bearing device.

  More preferably, as in the invention according to claim 5, the parking brake includes an intermediate member that is held in the stator stator housing so as to be able to transmit torque, and the intermediate member is displaced to be engaged with and disengaged from the rotating member. If the actuator is provided, the parking brake can be integrated with the drive unit, and the degree of freedom in layout can be improved by securing the space around the wheel bearing device.

  According to a sixth aspect of the present invention, a plurality of recesses are formed in the radially outer portion of the rotating member, and a plurality of through holes are formed in the radially outer side of the stator stator housing corresponding to the recesses. The intermediate member having a tapered surface is accommodated in the through holes, and the intermediate member may be displaced via the cylindrical member engaged with the tapered surface to be engaged with or disengaged from the recess. . According to a seventh aspect of the present invention, a plurality of concave portions and a tapered surface are formed in a radially outer portion of the rotating member, and the convex portion and the tapered surface that engage with the concave portion and the tapered surface are the intermediate portions. The intermediate member may be formed so as to be capable of transmitting torque to the stator stator housing and axially displaceable. In this way, by engaging the intermediate member with the recess of the stator stator housing, it is possible to secure a braking force larger than that of a conventional parking brake by slipping, thereby achieving a lighter and more compact device. it can.

  In the invention according to claim 8, the output of the electric motor is increased because the rotor of the electric motor is disposed in a state where the pair of stators are sandwiched via a predetermined axial clearance. In addition, the planetary speed reducer can be further reduced in weight and size.

  The invention according to claim 9 is characterized in that a plurality of rectangular openings are formed on the hub wheel and an inner ring fitted to the hub wheel in a uniform circumferential arrangement, and the circumferential direction of these openings is A recess is formed in the center, and a carrier pin serving as an output element of the second planetary speed reducer is fixed to the recess, and the planetary element is rotatably supported on the carrier pin. Space can be secured sufficiently, and the durability of the bearing portion can be improved against moment load, and the device can be further reduced in weight and size.

  Preferably, as in the invention described in claim 10, when the carrier pin has a two-sided width and the two-sided width is fitted into the recess, the carrier pin can be reliably secured with a simple configuration. It can be fixed to the wheel, and the planetary speed reducer can be easily assembled.

  In the invention according to claim 11, since each element of the planetary reduction gear is transmitted power by friction means, noise and vibration generated during power transmission can be suppressed as much as possible.

Further, in the invention according to claim 12, since each element of the planetary speed reducer is transmitted power by gear means, power can be transmitted efficiently without sliding contact, and lubrication enclosed in the bearing. It can also be lubricated with grease.

  An electric wheel drive device according to the present invention includes a wheel bearing device having double-row bearings, and first and second planetary reduction gears mounted on the wheel bearing device and connected via a connecting shaft. And a drive unit having an electric motor for driving the first planetary speed reducer, and the rotation of the electric motor is decelerated in two stages by the first planetary speed reducer and the second planetary speed reducer. Power is transmitted to the hub wheel constituting the wheel bearing device, and since the braking device is integrally attached to the rotating member, a sufficient space for the bearing portion can be secured, and the weight and size can be reduced. Can do. In addition, the cost can be reduced by sharing the parts, and the braking action can be applied before the vehicle is decelerated, so that the braking torque can be reduced and a lightweight and compact braking device in the radial direction can be provided.

  An electric wheel drive device according to the present invention includes a wheel bearing device having double-row bearings, and first and second planetary speed reducers mounted on the wheel bearing device and connected via a connecting shaft. And a drive unit having an electric motor for driving the first planetary reduction gear, wherein the wheel bearing device has a wheel mounting flange at one end and a small-diameter step formed on the outer periphery. A ring, an inner ring that is externally fitted to the small-diameter step portion of the hub wheel, and has an inner ring formed with at least one inner rolling surface of the double-row inner rolling surface on the outer periphery, and is opposed to the inner rolling surface on the inner periphery An outer member formed with a double-row outer rolling surface, and a double-row rolling element that is rotatably accommodated between the two rolling surfaces, the first planetary speed reducer An input element coupled to the shaft so as not to rotate relative thereto, 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; and an output element that rotatably supports the planetary elements with respect to a connection shaft, wherein the second planetary speed reducer includes the connection An input element coupled to the shaft so as not to rotate relative to the shaft; 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; An output element that rotatably supports these planetary elements with respect to the hub wheel, the drive unit constituting the electric motor, and a stator unit integrally disposed on the outer member, and the stator A rotor part facing the part via a predetermined air gap, and the rotor part is fixed, and is rotatably supported with respect to the outer member, and includes a rotating member integrally having the rotating shaft, The rotation of the electric motor is controlled by the first and second The wheel is driven by transmitting to the hub wheel via a star speed reducer, and a braking device is integrally attached to the rotating member, so that a sufficient space for the bearing portion can be secured and the moment load can be secured. It is possible to improve the durability by increasing the support strength of the bearing portion, and to reduce the weight and size of the entire apparatus. Further, the durability of the bearing portion can be improved with respect to the moment load applied to the device, and the unsprung weight of the vehicle can be reduced, so that the ride comfort and running stability can be improved.

  Wheel bearing device having double row bearings, first and second planetary reducers mounted on the wheel bearing device and connected via a connecting shaft, and driving the first planetary reducer A drive unit having an electric motor, and the wheel bearing device has a wheel mounting flange at one end, one inner rolling surface of the double row inner rolling surfaces on the outer periphery, and the inner rolling surface. A hub ring formed with a cylindrical small-diameter stepped portion extending in the axial direction from the surface, and an inner ring press-fitted into the small-diameter stepped portion and formed with the other inner rolling surface of the double row inner rolling surfaces on the outer periphery An inner member formed by the outer member, and an outer member that is extrapolated to the inner member and has a double-row outer rolling surface that is opposed to the inner rolling surface on the inner periphery, and between these rolling surfaces. And the first planetary speed reducer is connected to the rotation shaft so as not to rotate relative to the rotation shaft. A plurality of planetary rollers disposed between the inner peripheral surface of the outer member and the sun roller, and carrier pins that rotatably support the planetary rollers with respect to the connecting shaft. The second planetary speed reducer includes a sun roller coupled to the coupling shaft so as not to rotate relative to the coupling shaft, and a plurality of planetary rollers disposed between the inner circumferential surface of the outer member and the sun roller. A carrier pin for rotatably supporting these planetary rollers with respect to the hub wheel, the drive portion constituting the electric motor, and a stator portion integrally disposed on the outer member, and the stator A rotor part facing the part via a predetermined air gap, and the rotor part is fixed, and is rotatably supported with respect to the outer member, and includes a rotating member integrally having the rotating shaft, Rotation of the electric motor , Said first and second through the planetary reduction gear is transmitted to the wheel hub drives the wheel braking device to the rotating member is attached integrally.

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, FIG. 2 is a partial cross-sectional view taken along arrow A in FIG. 1, and FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. 1, and FIG. 5 is a cross-sectional view taken along line V-V in FIG.

  The electric wheel drive device includes a wheel bearing device 1, first and second planetary speed reducers 2, 2 ′ mounted on the wheel bearing device 1, and rotation of the first planetary speed reducer 2. The drive part 4 which has the axis | shaft 3 integrally is made into the main structure. In the following description, the side closer to the outside of the vehicle in the state assembled to the vehicle is referred to as the outboard side (left side in the drawing), and the side near the center is referred to as the inboard side (right side in the drawing).

  This wheel bearing device 1 is referred to as a third generation for supporting a driving wheel (not shown). This wheel bearing device 1 integrally has a wheel mounting flange 5a for attaching a wheel to an end portion on the outboard side, an inner rolling surface 5b on the outer periphery, and the inner rolling surface 5b on the inboard side. An inner member comprising a hub ring 5 formed with an extending cylindrical small-diameter step portion 5c, and an inner ring 6 fitted on the small-diameter step portion 5c of the hub ring 5 and having an inner raceway surface 6a formed on the outer periphery. 7 and a body mounting flange 8a that is externally attached to the inner member 7 and fixed to the vehicle body, and has a double row of outer rolling surfaces 8b facing the inner rolling surfaces 5b and 6a on the inner periphery. , 8b, an outer member 8 formed between the rolling surfaces 5b, 8b, 6a, and 8b. And a bearing cage 10 that holds the circumference equally. Further, seals 11 and 11 are attached to both ends of the outer member 8 to prevent leakage of lubricating grease sealed in the bearing and intrusion of dust, muddy water, and the like from the outside into the bearing.

  On the outer peripheral surface of the hub wheel 5, the surface hardness ranges from 54 to 64 HRC from the seal land portion of the outboard side seal 11 serving as the base portion of the wheel mounting flange 5 a to the inner rolling surface 5 b and the small diameter step portion 5 c. A hardened layer is formed. As the heat treatment, local heating is preferable, and quenching by high-frequency induction heating that can set the hardened layer depth relatively easily is preferable. Here, the end portion on the inboard side is unquenched with a surface hardness of 25 HRC or less, and is plastically deformed radially outward to form a crimped portion 5d. And the inner ring | wheel 6 externally fitted by the small diameter step part 5c of the hub ring 5 is being fixed to the axial direction by this crimping part 5d.

  In the present embodiment, a so-called self-retain structure is employed in which the internal clearance of the bearing is a negative clearance, the bearing rigidity is improved, and the inner ring 6 is fixed in the axial direction by the crimping portion 5d to maintain this preload amount. doing. Therefore, it is not necessary to manage the preload by firmly tightening the bearing portion with a nut or the like as in the prior art, so that the ease of incorporation into the vehicle can be simplified. In addition, although the double row angular contact ball bearing which used the ball | bowl for the rolling element 9 was illustrated here, not only this but the double row tapered roller bearing using a tapered roller may be sufficient.

  FIG. 2 is a cross-sectional view taken along the arrow A in FIG. 1, and a plurality of rectangular openings 12 are formed on the small-diameter step portion 5 c of the hub wheel 5 at equal intervals around the circumference. An opening 13 is also formed in the abutting portion 6 b of the inner ring 6 at a position corresponding to the opening 12 with the hub ring 5. Recesses 12a and 13a are respectively formed in the circumferential center portions of the openings 12 and 13, and a carrier pin (output element) 14 'of a second planetary speed reducer 2' to be described later is fixed. A 'planetary roller (planetary element) 15' is supported rotatably.

  Both end portions of the carrier pin 14 'are formed to have a two-sided width 14a, and are fitted to the recesses 12a and 13a and supported so as not to rotate. The planetary roller 15 ′ is rotatably supported via a rolling bearing 16 with respect to the carrier pin 14 ′. The planetary roller 15 'rolls along the inner circumferential surface 8c between the double row outer rolling surfaces 8b, 8b of the outer member 8 and the outer circumferential surface 17a' of the sun roller (input element) 17 '(see FIG. 3). In addition, although what illustrated the opening parts 12 and 13 in the butt | matching part 6b with the small diameter step part 5c of the hub ring 5 and the hub ring 5 of the inner ring | wheel 6 was illustrated here, not only this but not illustrated, A second generation structure in which a pair of inner rings are press-fitted into the small-diameter step portion of the hub ring may be applied. In this case, an opening is formed in the small-diameter step portion of the hub wheel, and an opening is formed in each of the abutting portions of the pair of inner rings positioned in the opening to support the planetary roller via the carrier pin. .

  In FIG. 1, a first planetary speed reducer 2 includes a sun roller (input element) 17 that is connected to the end of the rotating shaft 3 on the outboard side so as to be non-rotatable, such as press fitting or serration fitting, and the sun roller. Four planetary rollers (planetary elements) 15 that planetarily move around 17 and carrier pins (output elements) 14 that rotatably support the planetary rollers 15 with respect to the connecting shaft R are provided. A plurality of carrier pins 14 project from the outer portion of the flange portion Rf formed integrally with the connecting shaft R, and are supported so as not to rotate.

  The planetary roller 15 constituting the first planetary speed reducer 2 is rotatably supported via the rolling bearing 16 with respect to the carrier pin 14. The planetary roller 15 rotates in contact with the inner peripheral surface 8 d on the inboard side of the outer member (fixed element) 8 and the outer peripheral surface 17 a of the sun roller 17. The rotation of the rotating shaft 3 is transmitted to the planetary roller 15 via the sun roller 17, and the planetary roller 15 revolves, that is, decelerated to the connecting shaft R via the carrier pin 14.

  As described above, the second planetary speed reducer 2 ′ includes the sun roller 17 ′ connected to the end of the connecting shaft R so as to be able to transmit torque, and the four planets moving around the sun roller 17 ′. A roller 15 ′ and a carrier pin 14 ′ for rotatably supporting the planetary roller 15 ′ with respect to the hub wheel 5 and the inner ring 6 are provided. The rotation of the connecting shaft R is transmitted to the planetary roller 15 ′ through the sun roller 17 ′, decelerated by the planetary roller 15 ′, and transmitted to the wheel through the carrier pin 14 ′ and the hub wheel 5. Accordingly, the power transmission between the sun roller 17 ′ and the planetary roller 15 ′ and the planetary roller 15 ′ and the outer member (fixed element) 8 is performed by friction transmission (traction drive). Vibration can be suppressed as much as possible.

  The reduction ratio of the first and second planetary speed reducers 2 and 2 ′ is appropriately determined by changing the ratio of the outer diameter of the planetary rollers 15 and 15 ′ to the inner diameter of the inner peripheral surfaces 8c and 8d of the outer member 8. Although adjustable, for example, when applied to an electric wheel drive device for an electric vehicle, the reduction ratio can be set in the range of 3-9. The overall reduction ratio is the product of the reduction ratio m of the first planetary reduction gear 2 and the reduction ratio n of the second planetary reduction gear 2 ′, that is, m × n. Therefore, an extremely large reduction ratio can be obtained in a small space, and the electric motor 22 described later can be reduced in weight and size. Further, since the planetary rollers 15 and 15 ′ are disposed in the vicinity of the double row bearings in the wheel bearing device 1, the planetary rollers 15 and 15 ′ are biased toward the planetary rollers 15 and 15 ′ and the sun rollers 17 and 17 ′. It can suppress that a load acts.

  The drive unit 4 is fixed to the stator housing 18, and a stator 19 (see FIG. 4) around which an electromagnetic coil 19 b is wound around an iron core 19 a (see FIG. 4), and a rotating member facing the stator 19 via a predetermined air gap. A rotor 21 made up of a plurality of permanent magnets fixed to one side and formed in a substantially fan shape (see FIG. 5), and a rolling bearing 23 that rotatably supports the rotating member 20 with respect to the stator housing 18. I have. The rotating member 20 is rotated by energizing the electric motor 22 composed of the stator 19 and the rotor 21, and the rotation of the rotating member 20 is transmitted to the first planetary speed reducer 2 via the rotating shaft 3. The

  Here, a disc brake 24 is mounted on the outer peripheral portion of the rotating member 20. The disc brake 24 includes a brake pad 24a that holds the rotating member 20 from both sides, and a brake caliper 24b that presses the brake pad 24a via an actuator (not shown). In the present embodiment, since the rotating member 20 of the rotor 21 constituting the electric motor 22 is a brake rotor, the cost can be reduced by sharing parts. In addition, since the braking action can be applied by the disc brake 24 before decelerating by the first planetary speed reducer 2, the braking torque is reduced, and the disc brake 24 that is light and compact in the radial direction can be provided. . Further, the disc brake 24 also has a function as a parking brake.

  FIG. 6 is a longitudinal sectional view showing a second embodiment of the electric wheel drive device according to the present invention. The second embodiment is different from the first embodiment (FIG. 1) only in the configuration of the drive unit, and other parts having the same parts or the same functions are denoted by the same reference numerals and details thereof. The detailed explanation is omitted.

  As in the above-described embodiment, the drive unit 25 is fixed to the stator housing 18 and is opposed to the stator 19 in which the electromagnetic coil 19b is wound around the iron core 19a and the stator 19 through a predetermined air gap. A rotor 21 made of a plurality of permanent magnets fixed to one side of the rotating member 26 and formed in a substantially fan shape, and a rolling bearing 23 that rotatably supports the rotating member 26 with respect to the stator housing 18 are provided. . The rotating member 26 is rotated by energizing the electric motor 22 composed of the stator 19 and the rotor 21. The rotation of the rotating member 26 is transmitted to the first planetary speed reducer 2 via the rotating shaft 3. The

  Here, the rotating member 26 is formed with a cylindrical portion 26 a on the outer periphery, and shares a brake drum constituting the drum brake 27. A plurality of brake shoes 28 are arranged opposite to each other on the inner periphery of the cylindrical portion 26a. These brake shoes 28 are pressed against the cylindrical portion 26a via an actuator (not shown), and can be braked by the drum brake 27 before being decelerated by the first planetary speed reducer 2, and also function as a parking brake. Have both. Further, since the brake on the wheel side in the related art is disposed on the inboard side, a space around the wheel bearing device 1 can be secured, and the degree of design freedom in layout can be improved.

  FIG. 7 is a longitudinal sectional view showing a third embodiment of the electric wheel drive device according to the present invention. The third embodiment is different from the first embodiment (FIG. 1) only in the configuration of the electric motor, and other parts having the same parts or the same functions are denoted by the same reference numerals. Detailed description thereof is omitted.

  The sun roller 17 constituting the first planetary speed reducer 2 is connected to a rotating shaft 29 formed integrally with the rotating member 20 so as to transmit torque by press-fitting or serration fitting. The rotating shaft 29 is rotatably supported with respect to the stator housing 31 via a pair of rolling bearings 23, 23, and an electric motor 30 is mounted on the radially outer side thereof. The electric motor 30 has a stator 32 composed of an iron core 32a fixed to the stator housing 31 and an electromagnetic coil 32b wound around the iron core 32a, and is opposed to the stator 32 via a predetermined radial clearance. The inner rotor type electric motor 30 is configured by the rotor 33 disposed and fixed to the outer periphery of the rotary shaft 29.

  FIG. 8 is a longitudinal sectional view showing a fourth embodiment of the electric wheel drive device according to the present invention. The fourth embodiment is different from the first embodiment (FIG. 1) only in the configuration of the electric motor, and other parts having the same parts or the same functions are denoted by the same reference numerals and details thereof. The detailed explanation is omitted.

  The rotating shaft 34 integrally includes a rotating member 35 and is rotatably supported via a rolling bearing 23, 23 with respect to the pair of stator housings 18, 18. Further, the rotor 21 constituting the electric motor 36 is fixed to the outer periphery of the rotating member 35. A pair of stators 19, 19 are arranged to face each other via a predetermined axial clearance so as to sandwich the rotor 21, thereby constituting an electric motor 36. As a result, the output of the electric motor 36 is increased, and the first and second planetary speed reducers 2, 2 ′ can be reduced in weight and size.

  FIG. 9 is a longitudinal sectional view showing a fifth embodiment of the electric wheel drive device according to the present invention, and FIG. 10 is a sectional view taken along line XX of FIG. FIG. 11 shows a state when the brake is operated in FIG. The fifth embodiment is different from the above-described fourth embodiment (FIG. 8) only in the configuration of the braking portion, and other parts having the same parts or functions have the same reference numerals and details. The detailed explanation is omitted.

  A cylindrical portion 38 is formed on the outer edge of the rotating member 37 integrally formed with the rotating shaft 34, and a plurality of concave portions 38 a are formed on the inner periphery of the cylindrical portion 38 at equal intervals. A plurality of through holes 39a are formed in the radially outer portion of the stator housing 39 corresponding to the recesses 38a, and the intermediate member 40 is accommodated in the through holes 39a. The intermediate member 40 is a substantially rectangular parallelepiped with a tip having a spire shape, and a bottom surface is formed on a tapered surface 40 a. The tapered surface 40 a is in sliding contact with the tapered surface 42 a of the cylindrical member 42. And as shown in FIG. 12, the front-end | tip part is immersed in the pocket 41a of the cyclic | annular spring member 41. As shown in FIG.

  In FIG. 9, an actuator 43 is disposed in the vicinity of the cylindrical member 42, and is supported so as to be swingable about a fulcrum 43a. One end of the actuator 43 abuts on the end surface of the cylindrical member 42, and the other end is engaged with the brake wire 44. When the brake wire 44 is actuated, the actuator 43 swings around the fulcrum 43a and displaces the cylindrical member 42 in the axial direction (left side in the figure). Due to the displacement of the cylindrical member 42, the intermediate member 40 starts to move radially outward, and the tip end portion thereof engages with the recess 38 a of the rotating member 37 as shown in FIG. 11. As a result, the rotating member 37 and the stator housing 39 are integrated with each other via the intermediate member 40, and the rotating member 37 is fixed to the stator housing 39. At this time, the pocket 41a of the annular spring member 41 is expanded with the movement of the intermediate member 40, and the column part 41b between the pockets 41a is elastically deformed. Thus, when the brake is released by applying the brake wire 44, the intermediate member 40 moves radially inward by the restoring force of the elastically deforming column portion 41b and returns to the original position. Therefore, the recess 38a of the rotating member 37 and the intermediate member 40 are disengaged, and the connection between the rotating member 37 and the stator housing 39 is released.

  As described above, the intermediate member 40 is stably held by the through hole 39a of the stator housing 39 and the annular spring member 41, and the intermediate member 40 is smoothly returned to the original state by the elastic force of the spring member 41. And can provide a stable and reliable braking action. Therefore, by arranging the parking brake integrally with the rotating member 37 constituting the electric motor 36, the number of parts can be reduced and the cost can be reduced. Furthermore, since the braking force is larger than that of a conventional parking brake by sliding, the weight of the braking unit can be reduced.

  FIG. 13 is a longitudinal sectional view showing a sixth embodiment of the electric wheel drive device according to the present invention, and FIG. 14 is a sectional view taken along line XIV-XIV in FIG. The sixth embodiment is different from the fifth embodiment (FIG. 9) only in the configuration of the brake unit, and other parts having the same parts or the same functions are denoted by the same reference numerals and details thereof. The detailed explanation is omitted.

  A cylindrical portion 46 is formed on the outer edge of the rotating member 45 formed integrally with the rotating shaft 34, and a tapered surface 46 a is formed on the inner periphery of the cylindrical portion 46. A ring-shaped intermediate member 48 is accommodated in the tapered surface 46 a, the outer peripheral surface of the stator housing 47 and the annular space via an elastic member 49. The intermediate member 48 has an outer periphery formed on a tapered surface 48a corresponding to the tapered surface 46a, and an inner periphery is fitted to the stator housing 47 through a serration or the like so as not to rotate and to be slidable in the axial direction. ing.

  On the other hand, as shown in FIG. 14, a plurality of concave portions 45 a are formed on the inner surface of the rotating member 45 at equal intervals around the circumference. A plurality of convex portions 48b are formed on the front end portion of the intermediate member 48 facing the concave portions 45a at an equal circumference.

  In FIG. 13, an actuator 43 is disposed in the vicinity of the intermediate member 48, and is supported so as to be swingable about a fulcrum 43a. One end of the actuator 43 abuts on the end surface of the intermediate member 48, and the other end is engaged with the brake wire 44. When the brake wire 44 is applied, the actuator 43 swings around the fulcrum 43a and displaces the intermediate member 48 in the axial direction (left side in the figure) against the elastic member 49. Due to the displacement of the intermediate member 48, the tapered surface 48a of the intermediate member 48 abuts with the tapered surface 46a of the rotating member 45, and finally the convex portion 48b engages with the concave portion 45a. As a result, the rotating member 45 and the stator housing 47 are integrated via the intermediate member 48, and the rotating member 45 is fixed to the stator housing 47. Further, when the brake is released by applying the brake wire 44, the intermediate member 48 moves in the axial direction (right side in the figure) by the restoring force of the elastic member 49 and returns to the original position. Accordingly, the engagement between the concave portion 45a of the rotating member 45 and the convex portion 48b of the intermediate member 48 is released, and the connection between the rotating member 45 and the stator housing 47 is released.

  In this way, the intermediate member 48 is engaged with and disengaged from the rotating member 45 by sliding and uneven engagement, so that the braking action can be exerted even if the rotating member 45 is not completely stopped, and the uneven engagement is also achieved. It has a large braking force and can work a stable and reliable braking action. And by integrating a parking brake with the rotating member 45 which comprises the electric motor 36, a number of parts can be reduced and cost can be reduced. In addition, although the ring-shaped intermediate member 48 is illustrated here, the present invention is not limited to this, and it may be divided into a plurality of segments.

  FIG. 15 is a longitudinal sectional view showing a seventh embodiment of the electric wheel drive device according to the present invention. The ninth embodiment is different only in the configuration of the planetary speed reducer in the fourth embodiment (FIG. 8) described above, and other parts having the same parts or the same functions are denoted by the same reference numerals. Detailed description is omitted.

  The first planetary speed reducer 50 includes a sun gear (input element) 51 connected to the tip of the rotating shaft 34 so that torque can be transmitted, and four planetary gears (planetary movement) around the sun gear 51. Element) 52 and carrier pins (output elements) 14 that rotatably support the planetary gear 52 with respect to the connecting shaft R. The outer teeth 52 a of the planetary gear 52 mesh with the inner teeth 53 a formed on the inner peripheral surface of the outer member (fixed element) 53 and the outer teeth 51 a of the sun gear 51 and rotate.

  The rotation of the rotating shaft 34 is transmitted to the planetary gear 52 through the sun gear 51, and the rotation of the planetary gear 52 is decelerated through the carrier pin 14 and transmitted to the connecting shaft R. The second planetary speed reducer 2 ′ includes a sun gear 51 ′ connected to the end of the connecting shaft R so as to be able to transmit torque, and four planetary gears 52 ′ that perform planetary motion around the sun gear 51 ′. The planetary gear 52 ′ is provided with a carrier pin 14 ′ that rotatably supports the hub wheel 5 and the inner ring 6. The planetary gear 52 ′ is rotatably supported via the rolling bearing 16 with respect to the carrier pin 14 ′. The planetary gear 52 'rotates in mesh with inner teeth 53b formed on the inner periphery between the double row outer raceway surfaces 8b, 8b of the outer member 53 and outer teeth 51a' of the sun gear 51 '.

  The rotation of the connecting shaft R is transmitted to the planetary gear 52 ′ via the sun gear 51 ′, decelerated by the planetary gear 52 ′, and transmitted to the wheels via the carrier pin 14 ′ and the hub wheel 5. Therefore, the power transmission between the sun gear 51 ′ and the planetary gear 52 ′ and the planetary gear 52 ′ and the outer member 53 are all performed by the gear transmission mechanism, so that power transmission can be efficiently performed without sliding contact.

  FIG. 16 is a longitudinal sectional view showing an eighth embodiment of the electric wheel drive device according to the present invention. The eighth embodiment is different only in the configuration of the drive unit in the fourth embodiment (FIG. 8) described above, and the other parts having the same parts or the same functions are denoted by the same reference numerals and the details thereof are described. The detailed explanation is omitted.

  The drive unit 54 is fixed to the stator housing 18, and faces the pair of stators 19, 19 around which the electromagnetic coil 19 b is wound around the iron core 19 a, and the stator 19 through a predetermined air gap, and the rotating member 55. And a pair of rolling bearings 23 and 23 for rotatably supporting the rotating member 55 with respect to the stator housing 18. The rotating member 55 is rotated by energizing the electric motor 36 composed of the stator 19 and the rotor 21, and the rotation of the rotating member 55 is transmitted to the first planetary speed reducer 2 via the rotating shaft 34. The

  Here, a cooling fin 56 is integrally formed in the vicinity of the disc brake 24 of the rotating member 55. The cooling fins 56 rotate with the rotation of the rotating member 55, and the disk brake 24 can be cooled by the heat dissipation effect to suppress the temperature rise. Thereby, the heat of the disc brake 24 is prevented from being conducted to the electric motor 36 via the rotating member 55.

  The embodiment of the present invention has been described above, but the present invention is not limited to such an embodiment, and is merely an example, and various modifications can be made without departing from the scope of the present invention. Of course, the scope of the present invention is indicated by the description of the scope of claims, and further, the equivalent meanings described in the scope of claims and all modifications within the scope of the scope of the present invention are included. Including.

  The electric wheel drive device according to the present invention is a four-wheeled vehicle such as a fuel cell vehicle and an electric vehicle, a two-wheeled vehicle, a golf cart, a three-wheeled or four-wheeled cart for elderly people and persons with disabilities, and a construction site or a transportation industry. The present invention can be applied to a case where various vehicles such as a hand-held unicycle to a four-wheel vehicle to be used are electrically driven, or when auxiliary power is applied by electric drive.

It is a longitudinal section showing a 1st embodiment of an electric wheel drive concerning the present invention. It is A arrow directional view which made a part of FIG. It is a cross-sectional view along the III-III line of FIG. FIG. 4 is a cross-sectional arrow view taken along line IV-IV in FIG. 1. It is a cross-sectional arrow view along the VV line of FIG. It is a longitudinal cross-sectional view which shows 2nd Embodiment of the electrically driven wheel drive device which concerns on this invention. It is a longitudinal cross-sectional view which shows 3rd Embodiment of the electrically driven wheel drive device which concerns on this invention. It is a longitudinal cross-sectional view which shows 4th Embodiment of the electrically driven wheel drive device which concerns on this invention. It is a longitudinal cross-sectional view which shows 5th Embodiment of the electrically driven wheel drive device which concerns on this invention. FIG. 10 is a cross-sectional view taken along line XX in FIG. 9. It is sectional drawing which showed the state at the time of a brake action same as the above. It is a principal part perspective view of a braking part same as the above. It is a longitudinal cross-sectional view which shows 6th Embodiment of the electrically driven wheel drive device which concerns on this invention. It is a cross-sectional arrow view along the XIV-XIV line of FIG. It is a longitudinal cross-sectional view which shows 7th Embodiment of the electrically driven wheel drive device which concerns on this invention. It is a longitudinal cross-sectional view which shows 8th Embodiment of the electrically driven wheel drive device which concerns on this invention. It is a longitudinal cross-sectional view which shows the conventional electric wheel drive device.

Explanation of symbols

1 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Wheel bearing device 2, 50 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・Planetary reducer 2 ', 50' ... 2nd planetary reducer 3, 29, 34 ...・ Rotating shafts 4, 25, 54 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Driver 5 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Hub wheel 5a・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Wheel mounting flange 5b, 6a ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Inner rolling surface 5c ・ ・..... Small diameter step part 5d ........ Clamping part 6 ... .... Inner ring 7 ... Inner members 8, 53 ... ...・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Outside member 8a ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Car body mounting flange 8b ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・・ ・ ・ ・ ・ ・ ・ ・ Outer rolling surface 8c, 8d ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Inner peripheral surface 9 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・········· Rolling element 10 ··································· ... Seals 12, 13 ... Openings 12a, 13a ... Recesses 14, 14 ' ···················································································· Width across flats 15 and 15 '・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Planar rollers 16, 23 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Rolling bearings 17, 17 ′ ・ ・・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Sun Rollers 17a, 17a ′ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Outer surface 18 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・..... Stator housings 19, 32 ..... Stator 19a, 32a ..... Iron core 19b 32b ... Electromagnetic coils 20, 26, 35, 37, 45, 55 ... Rotating members 21, 33 ...・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Rotor 22, 30, 36 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Electric motor 24 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・Disc brake 24a ... Brake pad 24b ... Brake caliper 26a, 38, 46 ...・ ・ ・ ・ ・ ・ ・ Cylindrical part 27 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Brake drum 28 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・... Brake shoes 38a, 45a ......... Recess 39a ......... Through holes 40, 48 ...・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Intermediate member 40a, 42a, 46a, 48a ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Tapered surface 41 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・... Spring member 41a ... Pocket 41b ... Pillar 42 ... Cylindrical member 43 ... Actuator 43a ... ............ fulcrum 44 ... ..... Brake wire 48b ..... Projection 49 ... .... Elastic members 51a, 51a ', 52a ... External teeth 53a, 53b ... Internal teeth 56 ... ... cooling fin 101 ... electric wheel drive device 102 ... Tire 103 ... Wheel 104 ... .... Electric motor 105 ........... gear reducer 105a ... -1st gear 105b ... 2nd gear 05c ... 3rd gear 105d ... 4th gear 106 ...・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Case 106a, 110a, 111a ・ ・ ・ ・ ・ ・ ・ ・ Concavity 106b ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・Insertion hole 107 ... stator 108 ... rotor 109 ... ··················· output shaft 109a, 116a ......... one end 109b, 116b ... The other end 110, 111 ... the cover 110b ... the recess 112 ...・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Mounting flange 11 ..... Hub bolts 114, 115, 117, 118 ... Rolling bearings 116 ...・ ・ ・ ・ ・ ・ Support shaft m, n ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Reduction ratio R ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・・ ・ ・ ・ Connection shaft Rf ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Flange

Claims (12)

Wheel bearing device having double row bearings, first and second planetary reducers mounted on the wheel bearing device and connected via a connecting shaft, and driving the first planetary reducer A drive unit having an electric motor,
The rotation of the electric motor is decelerated in two stages by the first planetary speed reducer and the second planetary speed reducer to transmit power to the hub wheel constituting the wheel bearing device and to brake the rotating member. An electric wheel drive device characterized in that the device is integrally mounted. Wheel bearing device having double row bearings, first and second planetary reducers mounted on the wheel bearing device and connected via a connecting shaft, and driving the first planetary reducer A drive unit having an electric motor,
The wheel bearing device has a wheel mounting flange at one end, a hub wheel having a small-diameter stepped portion formed on the outer periphery, and is externally fitted to the small-diameter step portion of the hub wheel, and a double row inner rolling on the outer periphery. An inner member comprising an inner ring formed with at least one inner rolling surface among the surfaces, and a double row outer rolling surface that is extrapolated to the inner member and faces the inner rolling surface on the inner periphery An outer member formed with a double row rolling element accommodated between the rolling surfaces so as to roll freely,
The first planetary speed reducer includes an input element that is connected to a rotation shaft so as not to rotate relative thereto, a fixed element that is disposed on an inner peripheral side of the outer member, and a gap between the fixed element and the input element. A plurality of arranged planetary elements and an output element that rotatably supports these planetary elements with respect to the connecting shaft;
The second planetary speed reducer includes an input element coupled to the coupling shaft so as not to rotate relative thereto, a fixed element disposed on an inner peripheral side of the outer member, and between the fixed element and the input element. A plurality of planetary elements disposed on the output wheel and an output element that rotatably supports the planetary elements with respect to the hub wheel,
The drive unit constitutes the electric motor, and a stator unit integrally disposed on the outer member, a rotor unit facing the stator unit via a predetermined air gap, and the rotor unit are fixed. And a rotating member that is rotatably supported with respect to the outer member and integrally includes the rotating shaft,
The rotation of the electric motor is transmitted to the hub wheel via the first and second planetary speed reducers to drive the wheel, and a braking device is integrally attached to the rotating member. Electric wheel drive device.   3. The electric wheel drive device according to claim 1, wherein the planetary element of the second planetary speed reducer is disposed between double row outer rolling surfaces formed on an inner periphery of the outer member. .   The electric wheel drive device according to any one of claims 1 to 3, wherein the braking device is a parking brake.   The electric wheel according to claim 4, wherein the parking brake includes an intermediate member that is held in the stator stator housing so as to be able to transmit torque, and an actuator that displaces the intermediate member and engages and disengages the rotating member. Drive device.   A plurality of recesses are formed in the radially outer portion of the rotating member, and a plurality of through holes are formed in the radially outer portion of the stator housing corresponding to the recesses, and tapered surfaces are formed in the through holes. The electric wheel drive device according to claim 5, wherein the intermediate member is accommodated, and the intermediate member is displaced via a cylindrical member engaged with the tapered surface to be engaged with and disengaged from the recess.   A plurality of concave portions and a tapered surface are formed in a radially outer portion of the rotating member, and a convex portion and a tapered surface that engage with the concave portion and the tapered surface are formed on the intermediate member, and the intermediate member is the stator. 6. The electric wheel drive device according to claim 5, wherein the electric wheel drive device is held so as to be capable of transmitting torque to the housing and capable of axial displacement.   The electric wheel drive device according to any one of claims 1 to 7, wherein a pair of stators are disposed in a state of being sandwiched via a predetermined axial clearance with respect to a rotor of the electric motor.   A plurality of rectangular openings are formed on the hub ring and an inner ring fitted to the hub ring in a circumferentially equidistant manner, and a recess is formed at the center in the circumferential direction of the openings. The electric wheel drive device according to any one of claims 1 to 8, wherein a carrier pin serving as an output element of the second planetary speed reducer is fixed in the recess, and the planetary element is rotatably supported on the carrier pin. .   The electric wheel drive device according to claim 9, wherein a two-sided width is formed on the carrier pin, and the two-sided width is fitted in the recess.   The electric wheel drive device according to any one of claims 1 to 10, wherein each element of the planetary speed reducer is powered by friction means.   The electric wheel drive device according to any one of claims 1 to 10, wherein each element of the planetary reduction gear is transmitted with power by gear means.

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