Traveling device of wheel type vehicle

Abstract

To supply a sufficient amount of a lubrication oil to a bearing supporting a rotary shaft on a constant basis.SOLUTION: A travel device includes: a cylindrical spindle; a rotary shaft 14 which is provided at the inner periphery side of the spindle and rotated by a driving motor; a wheel attachment cylinder which is rotatably provided at the outer periphery side of the spindle and attached with a wheel and contains a lubrication oil therein; a speed reduction mechanism which reduces a speed of rotation of the rotary shaft 14 and transmits the rotation to the wheel attachment cylinder; a retainer 42 having a bearing fitting hole 42A and provided at the inner periphery side of the spindle; and a bearing 44 attached to the retainer 42 and supporting the rotary shaft 14. An annular flange part 42D which contacts with the bearing 44 is provided at a driving motor side surface of the retainer 42. An oil reservoir plate 47 which forms an oil reservoir part 49 of the lubrication oil with a flange part 42D and an inner peripheral surface 42C of the bearing fitting hole 42A is provided on a speed reduction mechanism side surface of the retainer 42.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to a traveling device that is suitably used for a wheeled vehicle having wheels, such as a dump truck. [Background technology]

[0002] In general, a traveling device provided on a wheeled vehicle, for example, a dump truck, includes a cylindrical spindle fixed to the vehicle body, a rotating shaft extending axially from the inner periphery of the spindle and driven to rotate by a driving source, a wheel mounting case rotatably provided on the outer periphery of the spindle, with wheels attached to the outer periphery and containing lubricant on the inner periphery, and a planetary gear reduction mechanism that reduces the rotation of the rotating shaft and transmits it to the wheel mounting case. The planetary gear reduction mechanism reduces the rotation output of a driving source such as an electric motor and transmits it to the wheels (driving wheels) via the wheel mounting case, thereby generating a large rotational torque at the driving wheels and causing the dump truck to travel (see Patent Document 1).

[0003] The rotating shaft of the traveling gear is provided between the drive source and the planetary gear reduction mechanism (sun gear) with the inner periphery side of the spindle extended in the axial direction. Therefore, the intermediate portion of the rotating shaft in the longitudinal direction is supported rotatably relative to the spindle by a bearing provided on the inner periphery side of the spindle. Since dump trucks transport heavy loads such as crushed stone excavated from mines, etc., a large rotational load acts on the traveling gear. For this reason, it is necessary to keep the rotating shaft and bearings in a state where they can always rotate smoothly by supplying sufficient lubricating oil to the bearings.

[0004] Here, if a large amount of lubricating oil is stored inside the traveling device, the traveling device will generate energy loss and heat due to the resistance (stirring resistance) when the lubricating oil is stirred by the planetary gear reduction mechanism. For this reason, the amount of lubricating oil stored inside the traveling device is generally set to the minimum required amount of oil (for example, about 1 / 5 to 1 / 3 of the internal volume of the wheel mounting tube). In this way, when the amount of lubricating oil is set to the minimum required amount of oil, the oil level of the lubricating oil is located below the rotating shaft, so the rotating shaft and bearings are not immersed in the lubricating oil, and the planetary gears, carriers, etc. that constitute the planetary gear reduction mechanism are partially immersed in the lubricating oil. Therefore, when the traveling device is driven, the lubricating oil is splashed up by the planetary gear reduction mechanism and scattered in the form of mist, and is appropriately supplied to the bearings.

[0005] However, the traveling gear according to Patent Document 1 is configured so that lubricating oil in a mist form is supplied to the bearings supporting the rotating shaft by the planetary gear reduction mechanism, and therefore there is a problem in that it is not possible to always supply sufficient lubricating oil to the bearings.

[0006] In response to this, a traveling device has been proposed in which an oil passage that guides lubricating oil to the bearing is formed in a retainer that holds the bearing to the spindle (see Patent Document 2). This traveling device is able to supply sufficient lubricating oil to the bearing by using a pump to suck up the lubricating oil contained inside the wheel mounting sleeve (drum) and supplying it to the oil passage formed in the retainer. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] US Patent Application Publication No. 2004 / 0065169 [Patent Document 2] JP 2010-116963 A Summary of the Invention [Problem to be solved by the invention]

[0008] However, in the traveling device of Patent Document 2, when the traveling device rotates at high speed, the lubricating oil contained inside the wheel mounting case is pressed against the inner peripheral surface of the wheel mounting case by centrifugal force, which can cause the liquid level of the lubricating oil to drop. This causes the pump to be unable to suck up the lubricating oil contained inside the wheel mounting case, resulting in a problem that the lubricating oil cannot be stably supplied to the bearings.

[0009] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a running device for a wheeled vehicle that is capable of constantly supplying sufficient lubricating oil to the bearings that support the rotating shaft. [Means for solving the problem]

[0010] The present invention relates to a cylindrical spindle that is fixed to the body of a wheeled vehicle and has a small diameter cylindrical portion that is open at its tip; a rotating shaft that extends axially around the inner periphery of the spindle, has a tip that protrudes from the open end of the small diameter cylindrical portion of the spindle and has a sun gear attached to the tip, and is driven to rotate by a drive source; a wheel mounting case that is rotatably provided on the outer periphery of the spindle, has a wheel attached to its outer periphery and contains lubricating oil inside; a reduction gear mechanism that reduces the rotation of the rotating shaft and transmits it to the wheel mounting case, the reduction gear mechanism including the sun gear; a retainer that has a bearing fitting hole and is provided on the inner periphery of the small diameter cylindrical portion of the spindle and is located between the drive source and the reduction gear mechanism; a bearing that is inserted into the bearing fitting hole of the retainer and rotatably supports an axial intermediate portion of the rotating shaft with respect to the spindle; and an annular stopper for positioning a drive source side surface of the retainer in the axial direction of the rotating shaft, the retainer having an annular flange portion that protrudes radially inward from the bearing fitting hole and abuts against the bearing, and an oil reservoir plate is provided on the reduction gear mechanism side of the retainer at a position axially opposite the flange portion via the bearing, the oil reservoir plate forming an oil reservoir for lubricating oil together with the flange portion and an inner surface of the bearing fitting hole, the oil reservoir plate being composed of an annular mounting portion attached to the retainer and an annular wall portion that protrudes radially inward from the annular mounting portion and faces the flange portion of the retainer over its entire circumference, an angle θ between the annular wall portion and an axial center line of the rotating shaft is set in the range of 0<θ<90°, and a radially inner edge portion of the annular wall portion approximately coincides with an end face of the stopper on the reduction gear mechanism side in the axial direction of the rotating shaft. Effect of the Invention

[0011] According to the present invention, the lubricating oil supplied to the bearing supporting the rotating shaft can be stored in the oil reservoir formed by the flange of the retainer, the inner peripheral surface of the bearing fitting hole, and the oil reservoir plate. As a result, regardless of the running state of the vehicle body, the bearing can be sufficiently supplied with lubricating oil stored in the oil reservoir, and the rotating shaft can be rotated smoothly. [Brief description of the drawings]

[0012] [Figure 1] 1 is a left side view showing a dump truck to which a traveling device according to a first embodiment of the present invention is applied. [Diagram 2] FIG. 2 is a rear view of the dump truck as seen from the rear. [Diagram 3] 3 is a cross-sectional view of the rear wheel side traveling device as viewed from the direction of arrows III-III in FIG. [Figure 4] FIG. 4 is an enlarged view showing the rotating shaft, bearings, retainer, oil sump plate, etc. in FIG. [Diagram 5] 5 is a cross-sectional view of the rotating shaft, bearings, retainer, oil sump plate, etc. as viewed from the direction of arrow VV in FIG. 4. [Figure 6] 5 is an enlarged view of a position similar to that of FIG. 4, showing a rotating shaft, a bearing, a retainer, an oil sump plate, etc. according to a second embodiment. [Figure 7] 5 is an enlarged view of a position similar to that of FIG. 4, showing a rotating shaft, a bearing, a retainer, an oil sump plate, etc. according to a third embodiment. [Figure 8] 8 is a cross-sectional view of the rotating shaft, bearings, retainer, oil sump plate, etc., as viewed from the direction of arrows VIII-VIII in FIG. 7. [Figure 9] 5 is an enlarged view similar to FIG. 4, showing a rotating shaft, bearings, a retainer, an oil sump plate, etc. according to a fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, a detailed description will be given of a wheeled vehicle travel device according to an embodiment of the present invention, with reference to the accompanying drawings, in which the travel direction of the dump truck is defined as the front-rear direction, and the direction perpendicular to the travel direction is defined as the left-right direction.

[0014] 1 to 5 show a first embodiment of the present invention. In the drawings, a dump truck 1 includes a vehicle body 2 having a sturdy frame structure, a vessel (cargo platform) 3 mounted on the vehicle body 2 so as to be able to rise and fall, a cab 5 provided at the front of the vehicle body 2, and left and right front wheels 6 and left and right rear wheels 7 as wheels.

[0015] The vessel 3 is formed as a large container for carrying heavy loads such as crushed stone, and the rear bottom of the vessel 3 is connected to the rear end of the vehicle body 2 via a connecting pin 4 or the like so that the vessel 3 can be raised and lowered (tilted). A hood 3A that covers a cab 5 from above is integrally provided on the front upper part of the vessel 3. The cab 5 is provided at the front of the vehicle body 2, located below the hood 3A. The cab 5 forms a driver's cab, and inside the cab 5, a driver's seat, a steering handle, a plurality of operating levers (none of which are shown), and the like are provided.

[0016] The left and right front wheels 6 are rotatably provided on the front side of the vehicle body 2 (only the left front wheel is shown). The left and right front wheels 6 constitute steering wheels that are steered by the driver. The left and right rear wheels 7 are rotatably provided on the rear side of the vehicle body 2 (only the left rear wheel is shown). The left and right rear wheels 7 constitute driving wheels of the dump truck 1, and are rotationally driven integrally with the wheel mounting case 16 by the traveling device 11 shown in FIG. 3. The rear wheel 7 includes two rows of tires 7A consisting of dual-wheel tires, and a rim 7B disposed radially inside the tires 7A.

[0017] The engine 8 is located below the cab 5 and is provided inside the vehicle body 2. The engine 8 is, for example, a diesel engine, and drives a travel motor 13, which will be described later, a hydraulic pump (not shown), and the like, which are mounted on the vehicle body 2. Pressurized oil discharged from the hydraulic pump is supplied to a hoist cylinder 9, which will be described later, a steering cylinder for power steering (not shown), and the like.

[0018] The hoist cylinders 9 are provided between the vehicle body 2 and the vessel 3. The hoist cylinders 9 are located between the front wheels 6 and the rear wheels 7, and are disposed on both the left and right sides of the vehicle body 2. The hoist cylinders 9 extend and contract upward and downward as pressure oil is supplied to and discharged from the hydraulic pump, and raise and lower (tilt) the vessel 3 about the connecting pin 4.

[0019] The rear wheel axle housing 10 is provided at the rear of the vehicle body 2. The axle housing 10 is made of a hollow cylinder extending in the left-right direction (axial direction), and is attached to the rear of the vehicle body 2 via left and right rear wheel suspensions 10A. Running gear 11 for driving the left and right rear wheels 7 are provided on both the left and right sides of the axle housing 10, respectively.

[0020] The traveling devices 11 are provided on both the left and right sides of the axle housing 10. As shown in Fig. 3, the traveling devices 11 include a spindle 12, a traveling motor 13, a rotating shaft 14, a wheel mounting sleeve 16, a reduction mechanism 21, a retainer 42, a bearing 44, and an oil reservoir plate 47. The traveling devices 11 reduce the rotation speed of the rotating shaft 14 by the reduction mechanism 21, and rotate and drive the left and right rear wheels 7, which serve as drive wheels, with a large rotational torque.

[0021] The spindle 12 is attached to both the left and right sides of the axle housing 10. The spindle 12 is formed in a stepped cylindrical shape extending in the left-right direction, and has a tapered portion 12A, an intermediate cylindrical portion 12B, and a small diameter cylindrical portion 12C. The tapered portion 12A has a tapered shape that gradually reduces in diameter from one axial side (the axle housing 10 side) of the spindle 12 to the other axial side, and is attached to the end of the axle housing 10 using a plurality of bolts 12D. The intermediate cylindrical portion 12B is formed integrally with the reduced diameter side of the tapered portion 12A and extends in the axial direction. The small diameter cylindrical portion 12C has an outer diameter smaller than that of the intermediate cylindrical portion 12B, and is formed integrally with the tip side of the intermediate cylindrical portion 12B.

[0022] A plurality of motor mounting seats 12E protruding radially inward are provided on one axial side of tapered portion 12A, and travel motors 13 are attached to motor mounting seats 12E. An annular flange portion 12F protruding radially outward is provided on the outer periphery of tapered portion 12A, and a wet brake 35 (described later) is attached to flange portion 12F.

[0023] On the other hand, the tip of the small diameter cylindrical portion 12C is an open end, and a cylindrical protrusion 33A of a second stage carrier 33 described later is splined to its inner periphery. An annular inner protrusion 12G protruding radially inward is integrally formed on the inner periphery of the axial middle portion of the small diameter cylindrical portion 12C, and a retainer 42 described later is attached to the inner protrusion 12G. Furthermore, a radial hole 12H penetrating in the up-down direction (radial direction of the small diameter cylindrical portion 12C) is formed in the lower portion of the small diameter cylindrical portion 12C, and a tip 38A of a suction pipe 38 described later is inserted into this radial hole 12H.

[0024] The traveling motor 13 as a drive source is disposed within the axle housing 10 and the tapered portion 12A of the spindle 12. A plurality of mounting flanges 13A are provided on the outer periphery of the traveling motor 13, and the mounting flanges 13A are attached to a motor mounting seat 12E of the spindle 12 (tapered portion 12A) using bolts or the like. The traveling motor 13 is constituted by an electric motor, and is supplied with electric power from a generator (not shown) mounted on the vehicle body 2 to rotate and drive the rotating shaft 14.

[0025] The rotating shaft 14 is provided by extending in the axial direction on the inner peripheral side of the spindle 12. The rotating shaft 14 is formed by using a single long rod-shaped body, and one end side of the rotating shaft 14 is connected to an output shaft (not shown) of the traveling motor 13 via a coupling 15, and the rotating shaft 14 is rotationally driven by the traveling motor 13. The other end side of the rotating shaft 14 protrudes from the open end of the small diameter cylindrical portion 12C of the spindle 12, and a sun gear 23 described later is attached to the other end (protruding end) of the rotating shaft 14. An intermediate portion of the rotating shaft 14 in the axial direction is supported by a bearing 44 so as to be rotatable relative to the spindle 12.

[0026] The wheel mounting case 16 is rotatably provided on the outer periphery of the small diameter cylindrical section 12C constituting the spindle 12 via two roller bearings 17, 18. The wheel mounting case 16 is supported by the roller bearings 17, 18 and has a hollow cylindrical section 16A extending axially on the outer periphery of the small diameter cylindrical section 12C, and an extension cylindrical section 16B protruding axially from the tip of the hollow cylindrical section 16A and extending in a direction away from the spindle 12. A cylindrical rim 7B constituting the rear wheel 7 is detachably attached to the outer periphery of the wheel mounting case 16, and the rear wheel 7 rotates integrally with the wheel mounting case 16. An internal gear 32 and an outer drum 19, which will be described later, are integrally fixed to the end of the extension cylindrical section 16B of the wheel mounting case 16 using a long bolt 20. The outer drum 19 is made of a cylindrical body, with a flange portion 19A provided on one axial side thereof being fixed to the wheel mounting case 16 via an internal gear 32, and the other axial side thereof being an open end.

[0027] The reduction mechanism 21 is provided between the rotating shaft 14 and the wheel mounting case 16. The reduction mechanism 21 is composed of a first-stage planetary gear reduction mechanism 22 and a second-stage planetary gear reduction mechanism 29, and transmits the rotation of the rotating shaft 14 to the wheel mounting case 16 after reducing its speed in two stages.

[0028] The first-stage planetary gear reduction mechanism 22 includes a sun gear 23, multiple planetary gears 24, and a carrier 26. The sun gear 23 is splined to the tip of the rotating shaft 14 protruding from the spindle 12 (small diameter cylindrical portion 12C). The multiple planetary gears 24 mesh with the sun gear 23 and a ring-shaped internal gear 25, and revolve around the sun gear 23 while rotating on their own axes. The carrier 26 is fixed via a bolt or the like to an open end of the outer drum 19 integrated with the wheel mounting case 16, and rotatably supports the planetary gear 24 via a support pin 27.

[0029] Here, the internal gear 25 is formed using a ring gear, and surrounds the sun gear 23 and the multiple planetary gears 24 from the radial outside. The internal gear 25 is disposed so as to be rotatable relative to the inner peripheral surface of the outer drum 19 via a radial gap. The rotation of the internal gear 25 is transmitted to a second-stage planetary gear reduction mechanism 29 via a coupling .

[0030] The coupling 28 is provided between the first-stage planetary gear reduction mechanism 22 and the second-stage planetary gear reduction mechanism 29. The coupling 28 is formed in a disk shape having a boss 28A at the center. The outer periphery of the coupling 28 is spline-connected to the first-stage internal gear 25, and the inner periphery of the boss 28A of the coupling 28 is spline-connected to the second-stage sun gear 30 described below. The coupling 28 transmits the rotation of the first-stage internal gear 25 to the second-stage sun gear 30, causing the sun gear 30 to rotate integrally with the first-stage internal gear 25.

[0031] The first-stage planetary gear reduction mechanism 22 converts the rotation of the sun gear 23 into rotational motion and revolutionary motion of the multiple planetary gears 24 as the sun gear 23 rotates integrally with the rotating shaft 14 by the travel motor 13. The rotational motion of the planetary gears 24 is then transmitted to the internal gear 25 as reduced rotation, and the rotation of the internal gear 25 is transmitted to the second-stage planetary gear reduction mechanism 29 via a coupling 28. Meanwhile, the revolutionary motion of the planetary gears 24 becomes the rotation of the carrier 26, which is transmitted to the wheel mounting case 16 via the outer drum 19. At this time, the wheel mounting case 16 rotates integrally with the second-stage internal gear 32, so the revolution of the planetary gears 24 is suppressed to rotation synchronized with the wheel mounting case 16.

[0032] The second-stage planetary gear reduction mechanism 29 includes a cylindrical sun gear 30, a plurality of planetary gears 31, and a carrier 33. The sun gear 30 is splined to the inner periphery of the boss 28A of the coupling 28, and rotates integrally with the coupling 28. The plurality of planetary gears 31 mesh with the sun gear 30 and a ring-shaped internal gear 32, and revolve around the sun gear 30 while rotating on their own axes. The carrier 33 rotatably supports the planetary gears 31 via a support pin 34. A cylindrical tubular protrusion 33A is provided at the center of the carrier 33, and the outer periphery of the tubular protrusion 33A is splined to the inner periphery of the small diameter cylindrical portion 12C. Here, the second stage internal gear 32 is formed using a ring gear that surrounds the sun gear 30, the multiple planetary gears 31, etc. from the radially outside, and is fixed integrally between the extended cylindrical portion 16B of the wheel mounting case 16 and the outer drum 19 using a long bolt 20.

[0033] In the second-stage planetary gear reduction mechanism 29, the revolution of the planetary gear 31 (the rotation of the carrier 33) is constrained by spline-connecting the cylindrical protrusion 33A of the carrier 33 to the small-diameter cylindrical portion 12C of the spindle 12. Therefore, in the second-stage planetary gear reduction mechanism 29, the sun gear 30 rotates integrally with the coupling 28, so that the rotation of the sun gear 30 is converted into the rotation of the planetary gear 31, and this rotation of the planetary gear 31 is transmitted to the second-stage internal gear 32. As a result, the internal gear 32 rotates at a reduced speed, and a large-output rotational torque that has been reduced in two stages by the first-stage planetary gear reduction mechanism 22 and the second-stage planetary gear reduction mechanism 29 is transmitted to the wheel mounting case 16 to which the internal gear 32 is fixed.

[0034] Here, lubricating oil L is stored inside the wheel mounting sleeve 16, and the liquid level of the lubricating oil L is at a position lower than, for example, the bottommost part of the small diameter cylindrical portion 12C that constitutes the spindle 12. Therefore, the lower parts of the roller bearings 17, 18 are immersed in the lubricating oil L, and a part of the planetary gear reduction mechanisms 22, 29 is constantly lubricated by the lubricating oil L. In addition, the lubricating oil L splashed up by the planetary gear reduction mechanisms 22, 29 becomes a mist and is scattered inside the spindle 12, and is also supplied to the bearing 44 that supports the rotating shaft 14. As a result, when the traveling device 11 is in operation, resistance due to agitation of the lubricating oil L is reduced, making it possible to suppress energy loss, and heat generation by the traveling device 11 can be suppressed.

[0035] The wet brake 35 is attached to the flange portion 12F of the spindle 12. The wet brake 35 is composed of a wet-type multi-plate hydraulic brake, and applies a braking force to a brake hub 36 attached to the wheel mounting case 16. This applies a braking force to the rotation of the wheel mounting case 16, i.e., the rotation of the rear wheel 7.

[0036] The partition wall 37 is provided inside the spindle 12. The partition wall 37 is formed of an annular plate, and the outer periphery of the partition wall 37 is attached using bolts or the like to the boundary between the tapered portion 12A and the intermediate cylindrical portion 12B of the spindle 12. The partition wall 37 divides the inside of the spindle 12 into a motor accommodating space portion 37A that accommodates the travel motor 13, and a cylindrical space portion 37B that communicates with the inside of the wheel mounting case 16.

[0037] The suction pipe 38 is provided in the spindle 12 and the axle housing 10. One lengthwise side of the suction pipe 38 extends axially inside the axle housing 10 and is connected to the suction side of the lubricating oil pump 39. The other lengthwise side of the suction pipe 38 is located below the rotating shaft 14, extends axially inside the spindle 12, and is held by a retainer 42, which will be described later. A tip 38A of the suction pipe 38 protruding from the retainer 42 is bent in an L-shape and extends downward, and is inserted into a radial hole 12H of the spindle 12. As a result, the tip 38A of the suction pipe 38 is immersed in the lubricating oil L inside the wheel mounting case 16, and the lubricating oil pump 39 sucks up the lubricating oil L through the suction pipe 38.

[0038] The supply pipe 40 is provided in the spindle 12 and the axle housing 10, and forms a circulation circuit for the lubricating oil L together with the suction pipe 38, the lubricating oil pump 39, etc. One side of the length of the supply pipe 40 extends axially inside the axle housing 10 and is connected to the discharge side of the lubricating oil pump 39. The other side of the supply pipe 40 is located above the rotating shaft 14, extends axially inside the spindle 12, and is held by a retainer 42. A tip 40A of the supply pipe 40 protruding from the retainer 42 extends into a cylindrical protruding portion 33A of the second stage carrier 33 along the rotating shaft 14 while being bent in an S-shape. An oil cooler 41 is provided midway along the supply pipe 40. As a result, the lubricating oil L discharged from the lubricating oil pump 39 is cooled by the oil cooler 41 and supplied to the rotating shaft 14 through the tip 40A of the supply pipe 40, cooling the rotating shaft 14 and also splashing from the rotating shaft 14 to lubricate the bearings 44, etc.

[0039] The retainer 42 is attached to the inner protrusion 12G of the spindle 12 (small diameter cylindrical portion 12C) using a bolt or the like. The retainer 42 is made of a disk with a bearing fitting hole 42A formed in the center, and holds the bearing 44 fitted in the bearing fitting hole 42A, and holds the other side in the length direction of the suction pipe 38 and the supply pipe 40. As shown in FIG. 4, an annular flange portion 42D that protrudes radially inward from an inner peripheral surface 42C of the bearing fitting hole 42A is provided on one axial side surface 42B of the retainer 42 that faces the traveling motor 13. An oil reservoir plate 47, which will be described later, is attached to the other axial side surface 42E of the retainer 42 that faces the reduction mechanism 21. Furthermore, an oil passage 42F that extends radially from the outer peripheral surface of the retainer 42 to the bearing fitting hole 42A is formed in the retainer 42. Oil passage 42F has one end (upper end) opening to the outer circumferential surface of retainer 42 and the other end (lower end) opening to bearing fitting hole 42A, and guides lubricating oil L scattered on the outer circumferential surface of retainer 42 to bearing fitting hole 42A.

[0040] The sleeve 43 is provided at a position on the rotating shaft 14 corresponding to the bearing fitting hole 42A of the retainer 42. The sleeve 43 is made of a stepped cylinder having a shaft mounting hole 43A, and the outer circumferential surface of the sleeve 43 has a large diameter outer circumferential surface 43B and a small diameter outer circumferential surface 43C. Furthermore, an annular flange portion 43D is provided on one axial side (the traveling motor 13 side) of the sleeve 43, projecting radially outward from the large diameter outer circumferential surface 43B.

[0041] The bearing 44 is disposed on the inner periphery of the spindle 12 via the retainer 42, and supports the rotating shaft 14 rotatably relative to the spindle 12. The bearing 44 includes an outer ring 44A, an inner ring 44B, and a plurality of rolling elements 44C. The outer ring 44A of the bearing 44 is fitted into the bearing fitting hole 42A of the retainer 42, and the inner ring 44B of the bearing 44 is fitted into the large diameter outer periphery 43B of the sleeve 43. The outer ring 44A of the bearing 44 is positioned in the axial direction by the flange portion 42D of the retainer 42 and a stop ring 45 attached to the inner periphery 42C of the bearing fitting hole 42A. The inner ring 44B of the bearing 44 is positioned in the axial direction by the flange portion 43D of the sleeve 43 and an annular stopper 46 shrink-fitted to the small diameter outer periphery 43C.

[0042] The oil sump plate 47 is attached to the other side surface 42E of the retainer 42 located on the reduction mechanism 21 side. That is, the oil sump plate 47 is provided on the reduction mechanism 21 side of the retainer 42 at a position (surface) that faces the flange portion 42D in the axial direction via the bearing 44. As shown in Figs. 4 and 5, the oil sump plate 47 is formed as a crescent-shaped plate having a length dimension larger than the outer diameter dimension of the rotating shaft 14 and a height dimension smaller than the outer diameter dimension of the rotating shaft 14. The oil sump plate 47 has an attachment portion 47A attached to the retainer 42 below the center of the bearing fitting hole 42, and a wall portion 47B that rises upward from the attachment portion 47A and faces the flange portion 42D of the retainer 42 in the axial direction.

[0043] The oil sump plate 47 has an attachment portion 47A attached to the other side surface 42E of the retainer 42 using a plurality of bolts 48. The center of the oil sump plate 47 in the longitudinal direction coincides with a vertical line passing through the axial center of the rotating shaft 14. In this state, the wall portion 47B of the oil sump plate 47 faces the flange portion 42D of the retainer 42 in the axial direction via (sandwiching) the bearing 44. As a result, the oil sump plate 47, together with the inner circumferential surface 42C of the bearing fitting hole 42A of the retainer 42 and the flange portion 42D, forms an oil sump portion 49 that stores lubricating oil L.

[0044] Here, upper edge 47C of wall portion 47B protrudes above lowermost portion 42G of inner circumferential surface 42C of bearing fitting hole 42A formed in retainer 42, and is located lower than lowermost portion 42J of inner circumferential edge 42H of flange portion 42D. As a result, even if the lubricating oil L stored in oil reservoir 49 exceeds the volume of oil reservoir 49, the lubricating oil L is prevented from overflowing over flange portion 42D of retainer 42 and overflowing toward travel motor 13, thereby protecting travel motor 13.

[0045] In this manner, in this embodiment, the oil reservoir 49 is formed by the oil reservoir plate 47, the inner circumferential surface 42C of the bearing fitting hole 42A of the retainer 42, and the flange portion 42D. As a result, the lubricating oil L that is discharged from the lubricating oil pump 39 and supplied to the rotating shaft 14, and then scattered from the rotating shaft 14 and moved from the inner circumferential surface of the spindle 12 to the outer circumferential surface of the retainer 42, or the mist-like lubricating oil L that is splashed up by the reduction gear mechanism 21 or the like and scattered onto the outer circumferential surface of the retainer 42, is guided to the bearing fitting hole 42A through the oil passage 42F of the retainer 42 and is stored in the oil reservoir 49.

[0046] The traveling device 11 of the dump truck 1 according to this embodiment has the configuration described above, and its operation will now be described.

[0047] When the driver in the cab 5 of the dump truck 1 starts the engine 8, the hydraulic pump is rotated and power is generated by a generator (neither of which is shown). When the dump truck 1 is driven to travel, power is supplied from the generator to the travel motor 13, which operates to rotate the rotary shaft 14.

[0048] The rotation of the rotating shaft 14 is reduced and transmitted from the sun gear 23 of the first-stage planetary gear reduction mechanism 22 to the planetary gear 24, and the rotation of the planetary gear 24 is reduced and transmitted to the sun gear 30 of the second-stage planetary gear reduction mechanism 29 via the internal gear 25 and the coupling 28. In the second-stage planetary gear reduction mechanism 29, the rotation of the sun gear 30 is reduced and transmitted to the planetary gear 31. At this time, the cylindrical protrusion 33A of the carrier 33 supporting the planetary gear 31 is spline-connected to the small diameter cylindrical portion 12C of the spindle 12, so that the revolution of the planetary gear 31 (the rotation of the carrier 33) is restricted.

[0049] Therefore, the planetary gear 31 only rotates around the sun gear 30, and the rotation reduced by the rotation of the planetary gear 31 is transmitted to the internal gear 32 fixed to the wheel mounting case 16. As a result, the wheel mounting case 16 rotates with a large rotational torque that is reduced in two stages by the first-stage planetary gear reduction mechanism 22 and the second-stage planetary gear reduction mechanism 29. As a result, the left and right rear wheels 7, which serve as drive wheels, rotate integrally with the wheel mounting case 16, and the dump truck 1 can be driven to travel.

[0050] An axially intermediate portion of the rotating shaft 14 is rotatably supported by the spindle 12 via a bearing 44 and a retainer 42. This makes it possible to prevent the axially intermediate portion from bending radially or from vibrating due to eccentricity of the rotating shaft 14 when the rotating shaft 14 rotates at high speed, thereby improving the durability of the rotating shaft 14.

[0051] When the traveling device 11 is in operation, the lubricating oil L stored in the wheel mounting case 16 is scooped up by the planetary gears 24, 31 and the like that constitute the planetary gear reduction mechanisms 22, 29, and is supplied to the meshing portions between the gears, the roller bearings 17, 18, the bearing 44, etc. Then, the lubricating oil L drips downward in sequence and is collected on the lower side of the wheel mounting case 16.

[0052] The lubricating oil L collected on the lower side of the wheel mounting case 16 is sucked up from tip 38A of suction pipe 38 by lubricating oil pump 39, cooled in an oil cooler 41, and then discharged from tip 40A of supply pipe 40 onto the outer circumferential surface of the rotating shaft 14. The lubricating oil L discharged onto the outer circumferential surface of the rotating shaft 14 cools the rotating shaft 14, and is scattered by the rotation of the rotating shaft 14, lubricating the bearings 44, the planetary gear reduction mechanisms 22, 29, etc.

[0053] At this time, the lubricating oil L splashed up by the planetary gear reduction mechanism 22, 29 and some of the lubricating oil L scattered by the rotation of the rotating shaft 14 adhere to the inner circumferential surface of the small diameter cylindrical portion 12C constituting the spindle 12. The lubricating oil L adhering to the inner circumferential surface of the small diameter cylindrical portion 12C moves along the inner protrusion 12G of the small diameter cylindrical portion 12C to the outer circumferential surface of the retainer 42, and is then guided to the bearing fitting hole 42A through the oil passage 42F of the retainer 42. The lubricating oil L guided to the bearing fitting hole 42A lubricates the bearing 44 and flows toward the lower side of the bearing fitting hole 42A, and is stored in the oil reservoir 49 formed by the inner circumferential surface 42C, the flange portion 42D, and the oil reservoir plate 47 of the bearing fitting hole 42A.

[0054] Here, when the traveling device 11 rotates at high speed, the lubricating oil L contained inside the wheel mounting case 16 may be pressed against the inner peripheral surface of the wheel mounting case 16 by centrifugal force, causing the liquid level of the lubricating oil L to drop. In this case, the tip 38A of the suction pipe 38 separates from the lubricating oil L, and the lubricating oil pump 39 will no longer be able to suck up the lubricating oil L.

[0055] In contrast, in this embodiment, the lubricating oil L can be stored in the oil reservoir 49 formed by the inner circumferential surface 42C of the bearing fitting hole 42A, the flange 42D, and the oil reservoir plate 47. Therefore, the lubricating oil L stored in the oil reservoir 49 can be sufficiently supplied to the bearing 44 regardless of the traveling state of the dump truck 1. As a result, the rotating shaft 14 supported by the spindle 12 via the bearing 44 and the like can be rotated smoothly at all times, the traveling device 11 can be operated stably for a long period of time, and its reliability can be improved.

[0056] Moreover, upper edge 47C of wall portion 47B of oil reservoir plate 47 is positioned lower than lowermost portion 42J of inner circumferential edge 42H of flange 42D provided on retainer 42. As a result, even if the lubricating oil L stored in oil reservoir 49 exceeds the volume of oil reservoir 49, the lubricating oil L is prevented from overflowing over flange 42D of retainer 42 and overflowing toward travel motor 13, thereby protecting travel motor 13.

[0057] Thus, in the first embodiment, there is a cylindrical spindle 12 fixed to the vehicle body 2, a rotating shaft 14 extending axially from the inner periphery of the spindle 12 and driven to rotate by a travel motor 13, a wheel mounting case 16 rotatably provided on the outer periphery of the spindle 12, a wheel 7 is attached to the outer periphery of the spindle 12, and lubricating oil L is contained therein, a reduction mechanism 21 that reduces the rotation of the rotating shaft 14 and transmits it to the wheel mounting case 16, a retainer 42 having a bearing fitting hole 42A, positioned between the travel motor 13 and the reduction mechanism 21, and provided on the inner periphery of the spindle 12, In the traveling device 11 having a bearing 44 inserted into a bearing fitting hole 42A of a retainer 42 and supporting the rotating shaft 14 rotatably relative to the spindle 12, a ring-shaped flange portion 42D is provided on the surface of the retainer 42 facing the traveling motor 13 (one side 42B) which protrudes radially inward from the bearing fitting hole 42A and abuts the bearing 44, and an oil reservoir plate 47 is provided on the surface of the retainer 42 facing the reduction mechanism 21 (the other side 42E) which faces the flange portion 42D in the axial direction and forms an oil reservoir portion 49 for lubricating oil L together with the flange portion 42D and the inner surface 42C of the bearing fitting hole 42A.

[0058] According to this configuration, the lubricating oil L supplied to the bearing 44 supporting the rotating shaft 14 can be stored in the oil reservoir 49. As a result, the lubricating oil L stored in the oil reservoir 49 can be supplied sufficiently to the bearing 44 at all times, regardless of the traveling state of the dump truck 1. As a result, the rotating shaft 14 can be rotated smoothly at all times, so that the traveling device 11 can be operated stably for a long period of time, and its reliability can be improved.

[0059] In the embodiment, the oil reservoir plate 27 has an attachment portion 47A attached to the retainer 42 below the center of the bearing fitting hole 42A, and a wall portion 47B that rises upward from the attachment portion 47A and faces the raised flange portion 42D in the axial direction, and an upper edge 47C of the wall portion 47B is located at a position lower than the lowermost portion 42J of the inner peripheral edge 42H of the flange portion 42D. With this configuration, even if the lubricating oil L stored in the oil reservoir portion 49 exceeds the volume of the oil reservoir portion 49, the lubricating oil L is prevented from overflowing over the flange portion 42D of the retainer 42 and overflowing toward the traveling motor 13, thereby protecting the traveling motor 13.

[0060] Next, Fig. 6 shows a second embodiment of the present invention. The feature of this embodiment is that an extension part is provided between the mounting part and the wall part of the oil sump plate. In this embodiment, the same components as those in the first embodiment are given the same reference numerals, and the description thereof is omitted.

[0061] In the drawings, the oil sump plate 51 is attached to the other side surface 42E of the retainer 42 located on the side of the reduction gear mechanism 21. The oil sump plate 51 has an attachment portion 51A and a wall portion 51B, similar to the oil sump plate 47 according to the first embodiment. However, the oil sump plate 51 differs from the oil sump plate 47 according to the first embodiment in that an extension portion 51C is provided between the attachment portion 51A and the wall portion 51B.

[0062] The mounting portion 51A of the oil reservoir plate 51 is attached to the other side surface 42E of the retainer 42 by using the bolts 48 below the center of the bearing fitting hole 42. The extension portion 51C of the oil reservoir plate 51 protrudes from the mounting portion 51A toward the reduction gear mechanism 21 and extends in the axial direction toward the reduction gear mechanism 21. The wall portion 51B of the oil reservoir plate 51 rises upward from the protruding end of the extension portion 51C and faces the flange portion 42D of the retainer 42 in the axial direction. The upper end edge 51D of the wall portion 51B protrudes upward from the lowermost portion 42G of the inner circumferential surface 42C of the bearing fitting hole 42A formed in the retainer 42, and is located at a position lower than the lowermost portion 42J of the inner circumferential edge 42H of the flange portion 42D.

[0063] As a result, oil reservoir plate 51, together with inner circumferential surface 42C of bearing fitting hole 42A of retainer 42 and flange portion 42D, forms oil reservoir portion 52 that retains lubricating oil L. In this case, oil reservoir plate 51 is provided with expansion portion 51C extending in the axial direction between mounting portion 51A and wall portion 51B, so that the volume of oil reservoir portion 52 can be expanded by the amount of expansion portion 51C.

[0064] The traveling device according to the second embodiment has the oil reservoir plate 51 as described above, and its basic function is not particularly different from that of the traveling device 11 according to the first embodiment. However, the oil reservoir plate 51 according to this embodiment is provided with an expansion portion 51C extending in the axial direction between the mounting portion 51A and the wall portion 51B, so that the volume of the oil reservoir portion 52 formed together with the inner circumferential surface 42C of the bearing fitting hole 42A and the flange portion 42D can be expanded. As a result, the lubricating oil L stored in the oil reservoir portion 52 can be increased, and the bearing 44 can be properly lubricated for a long period of time.

[0065] Thus, in the second embodiment, between the mounting portion 51A and the wall portion 51B of the oil reservoir plate 51, there is provided an extension portion 51C that extends in the axial direction from the mounting portion 51A toward the reduction gear mechanism 21 and expands the oil reservoir portion 52. According to this configuration, the amount of lubricating oil L stored in the oil reservoir portion 52 is increased by the amount of the extension portion 51C provided, so that the bearing 44 can be properly lubricated for a long period of time.

[0066] 7 and 8 show a third embodiment of the present invention. The feature of this embodiment is that the oil sump plate is composed of an annular mounting portion attached to the retainer and an annular wall portion extending radially inward from the annular mounting portion. In this embodiment, the same components as those in the first embodiment are given the same reference numerals and their description will be omitted.

[0067] In the drawing, the oil sump plate 61 is attached to the other side 42E of the retainer 42 located on the reduction gear mechanism 21 side. The oil sump plate 61 is made of an annular plate as a whole, and has a flat annular mounting portion 61A located on the outer periphery side and a tapered annular wall portion 61B protruding radially inward from the inner periphery side of the annular mounting portion 61A. The inner periphery side of the annular wall portion 61B forms a circular shaft insertion hole 61C, and the rotating shaft 14 is inserted into the shaft insertion hole 61C. The annular mounting portion 61A is attached to the other side 42E of the retainer 42 by using the bolts 48. The center of the oil sump plate 61 coincides with the center of the rotating shaft 14, and the annular wall portion 61B of the oil sump plate 61 faces the flange portion 42D of the retainer 42 over the entire circumference.

[0068] An inner peripheral edge 61D of the annular wall portion 61B is positioned radially inward from an inner peripheral surface 42C of a bearing fitting hole 42A formed in the retainer 42, and positioned radially outward from an inner peripheral edge 42H of the flange portion 42D. As a result, the oil reservoir plate 61, together with the inner peripheral surface 42C of the bearing fitting hole 42A of the retainer 42 and the flange portion 42D, forms an oil reservoir portion 62 that retains lubricating oil L.

[0069] The annular wall portion 61B of the oil reservoir plate 61 tapers toward the reduction gear mechanism 21 from the other side surface 42E of the retainer 42 while gradually reducing in diameter toward the rotating shaft 14. Here, assuming that the axial center line of the rotating shaft 14 is AA, the angle θ at which the tapered annular wall portion 61B and the axial center line AA of the rotating shaft 14 intersect is set in a range greater than 0 and smaller than 90° (0<θ<90°). In this manner, the tapered annular wall portion 61B covers the entire circumference of the bearing 44 of the rotating shaft 14 from the outer periphery side. As a result, the lubricating oil L scattered from the rotating shaft 14, the sleeve 43, the stopper 46, etc. during the rotation of the rotating shaft 14 can be received by the annular wall portion 61B and then smoothly guided to the oil reservoir portion 62 along the tapered annular wall portion 61B.

[0070] The traveling device according to the third embodiment has the oil reservoir plate 61 as described above, and its basic function is not particularly different from that of the traveling device 11 according to the first embodiment. However, the oil reservoir plate 61 according to this embodiment has a flat annular annular mounting portion 61A attached to the other side surface 42E of the retainer 42, and an annular annular wall portion 61B extending radially inward from the inner circumferential side of the annular mounting portion 61A. The annular wall portion 61B protrudes in a tapered manner toward the reduction gear mechanism 21 while gradually reducing in diameter toward the rotating shaft 14, and the angle θ between the annular wall portion 61B and the axial center line AA of the rotating shaft 14 is set in the range of 0<θ<90°. As a result, the lubricating oil L scattered from the rotating shaft 14, the sleeve 43, the stopper 46, etc. can be collected by the tapered annular wall portion 61B and efficiently stored in the oil reservoir portion 62. As a result, the rotating shaft 14 can be rotated smoothly at all times, and the traveling device 11 can be operated stably for a long period of time.

[0071] Thus, in the third embodiment, the oil reservoir plate 61 is composed of an annular mounting portion 61A attached to the retainer 42, and an annular wall portion 61B extending radially inward from the annular mounting portion 61A and facing the flange portion 42D of the retainer 42 over the entire circumference. With this configuration, the periphery of the bearing 44 of the rotating shaft 14 can be covered from the outer periphery by the tapered annular wall portion 61B, and the lubricating oil L scattered from the periphery of the bearing 44 of the rotating shaft 14 can be received by the annular wall portion 61B and then guided to the oil reservoir portion 62 along the inclination of the annular wall portion 61B.

[0072] In the third embodiment, the angle θ between the annular wall portion 61B of the oil reservoir plate 61 and the axial center line AA of the rotating shaft 14 is set in the range of 0<θ<90°. With this configuration, the lubricating oil L scattered around the bearing 44 of the rotating shaft 14 can be collected by the tapered annular wall portion 61B and efficiently stored in the oil reservoir portion 62.

[0073] Next, Fig. 9 shows a fourth embodiment of the present invention. The feature of this embodiment is that a cylindrical sleeve with a bearing fitting portion on the outer periphery is attached to the rotating shaft, and an annular sleeve-side flange that protrudes radially outward from the bearing fitting portion is provided on the surface of the sleeve facing the driving source. In this embodiment, the same components as those in the first embodiment are given the same reference numerals, and their description will be omitted.

[0074] In the drawings, sleeve 71 is provided at a position on rotating shaft 14 corresponding to bearing fitting hole 42A of retainer 42. Like sleeve 43 according to the first embodiment, sleeve 71 is made of a stepped cylinder having shaft mounting hole 71A, and the outer circumferential surface of sleeve 71 has large diameter outer circumferential surface 71B as a bearing fitting portion and small diameter outer circumferential surface 71C having a smaller diameter than large diameter outer circumferential surface 71B. However, sleeve 71 differs from sleeve 43 according to the first embodiment in that a sleeve-side flange 71E, which will be described later, is provided on one axial side (travel motor 13 side) of sleeve 71.

[0075] The sleeve 71 has a large diameter outer circumferential surface 71B as a bearing fitting portion into which the inner ring 44B of the bearing 44 fits, and an annular sleeve side flange 71E that protrudes radially outward from the large diameter outer circumferential surface 71B is provided on one side surface 71D that is one axial side (travel motor 13 side) of the sleeve 71. The outer diameter of the sleeve side flange 71E is set to be larger than the outer diameter of the inner ring 44B that constitutes the bearing 44 and smaller than the inner diameter of the outer ring 44A. The inner ring 44B of the bearing 44 is positioned in the axial direction by abutting against the stopper 46 that is fitted into the small diameter outer circumferential surface 71C of the sleeve 71 and the sleeve side flange 71E. In this state, the outer peripheral edge of the sleeve side flange 71E faces the inner peripheral edge of the flange 42D provided on the retainer 42 with a small annular gap, and the sleeve side flange 71E, together with the flange 42D of the retainer 42, covers the bearing 44 from the driving motor 13 side.

[0076] The traveling device according to the fourth embodiment has the sleeve 71 as described above, and its basic operation is not particularly different from that of the traveling device 11 according to the first embodiment. However, in this embodiment, the outer peripheral edge of the sleeve-side flange 71E provided on the sleeve 71 faces the inner peripheral edge of the flange 42D provided on the retainer 42 with a small annular gap therebetween, and the sleeve-side flange 71E, together with the flange 42D of the retainer 42, covers the bearing 44 from the traveling motor 13 side. As a result, even if the lubricating oil L stored in the oil reservoir 49 exceeds the volume of the oil reservoir 49, the flange 42D of the retainer 42 and the sleeve-side flange 71E of the sleeve 71 can reliably prevent the lubricating oil L from overflowing onto the traveling motor 13 side, and the traveling motor 13 can be protected.

[0077] Thus, in the fourth embodiment, a cylindrical sleeve 71 having a large diameter outer circumferential surface 71B on the outer circumferential side is attached to the rotating shaft 14, the bearing 14 is inserted into the bearing fitting hole 42A of the retainer 42 via the sleeve 71, and a sleeve-side flange 71E is provided on the surface of the sleeve 71 facing the traveling motor 13, which protrudes radially outward from the large diameter outer circumferential surface 71B and covers the bearing 14 from the traveling motor 13 side together with the flange 42D of the retainer 42. With this configuration, when the lubricating oil L stored in the oil reservoir 49 exceeds the volume of the oil reservoir 49, the flange 42D of the retainer 42 and the sleeve-side flange 71E of the sleeve 71 can prevent the lubricating oil L from overflowing onto the traveling motor 13 side.

[0078] In the embodiment, a case is illustrated in which the lubricating oil L supplied from a circulation circuit formed by the suction pipe 38, the lubricating oil pump 39, the supply pipe 40, etc., and the mist-like lubricating oil L splashed up by the reduction gear mechanism 21 are used to lubricate the rotating shaft 14, the roller bearings 17, 18, the reduction gear mechanism 21, the bearing 44, etc. However, the present invention is not limited to this, and for example, a configuration may be used in which only one of the lubricating oil L, either the lubricating oil L supplied from the circulation circuit or the mist-like lubricating oil L splashed up by the reduction gear mechanism 21, is used.

[0079] In the first embodiment, the oil reservoir plate 27 is formed in a crescent shape. However, the present invention is not limited to this, and may be configured to use an oil reservoir plate having various shapes, such as a rectangular shape.

[0080] Furthermore, in the embodiment, the rear-wheel drive dump truck 1 has been taken as an example for explanation. However, the present invention is not limited to this, and may be applied to, for example, a front-wheel drive dump truck or a four-wheel drive dump truck in which both the front and rear wheels are driven. [Explanation of symbols]

[0081] 1. Dump truck 2. Body 7 Rear wheel (wheel) 12 Spindle 13. Driving motor (drive source) 14 Rotational Axis 16 Wheel mounting tube 21 Reduction mechanism 42 Retainer 42A Bearing fitting hole 42C Inner surface 42D Tsubabe 44 Bearings 47,51,61 Oil sump plate 47A, 51A mounting part 47B,51B wall part 51C Extension 61A Circular mounting part 61B Annular wall 49, 52, 62 Oil reservoir 71 Sleeve 71B Large diameter outer periphery (bearing fitting part) 71E Sleeve side flange

Claims

1. a cylindrical spindle that is fixed to a body of a wheeled vehicle and has a small diameter cylindrical portion with an open tip; a rotating shaft that is provided on the inner peripheral side of the spindle and extends in the axial direction, has a tip that protrudes from the open end of the small diameter cylindrical portion of the spindle, has a sun gear attached to the tip, and is rotated by a drive source; a wheel mounting sleeve that is rotatably provided on an outer periphery of the spindle, a wheel is mounted on the outer periphery of the wheel mounting sleeve, and a lubricating oil is contained therein; a reduction mechanism including the sun gear that reduces the rotation of the rotating shaft and transmits the reduced rotation to the wheel mounting case; a retainer having a bearing fitting hole and located between the drive source and the reduction mechanism and provided on an inner peripheral side of the small diameter cylindrical portion of the spindle; a bearing that is inserted into the bearing fitting hole of the retainer and supports an axial intermediate portion of the rotating shaft rotatably relative to the spindle; a ring-shaped stopper that is fitted to the rotating shaft and abuts against the reduction mechanism side of the bearing to position the bearing in the axial direction of the rotating shaft, the retainer has an annular flange on a surface facing the driving source, the flange protruding radially inward from the bearing fitting hole and coming into contact with the bearing, an oil reservoir plate that forms an oil reservoir for lubricating oil together with the flange and an inner circumferential surface of the bearing fitting hole is provided at a position axially opposed to the flange via the bearing on the reduction mechanism side of the retainer; the oil sump plate is configured with an annular mounting portion attached to the retainer, and an annular wall portion extending radially inward from the annular mounting portion and facing the flange portion of the retainer over an entire circumference, an angle θ between the annular wall portion and a center line of the rotation shaft is set in a range of 0<θ<90°; A running device for a wheeled vehicle, characterized in that a radially inner edge of the annular wall portion approximately coincides with an end face of the stopper on the side of the reduction mechanism in the axial direction of the rotating shaft.

2. A cylindrical sleeve is attached to the rotating shaft, the outer periphery of which serves as a bearing fitting portion, The bearing is inserted into the bearing fitting hole of the retainer via the sleeve, The running device for a wheeled vehicle as described in claim 1, characterized in that a sleeve side flange portion is provided on the surface of the sleeve facing the drive source, which protrudes radially outward from the bearing fitting portion and, together with the flange portion of the retainer, covers the bearing from the drive source side.

3. a lubricating oil pump that sucks in and discharges lubricating oil from within the wheel mounting case; 2. The traveling device for a wheeled vehicle according to claim 1, further comprising: a supply pipe for guiding the lubricating oil discharged from the lubricating oil pump to an upper portion of the retainer.

4. 4. The traveling device for a wheeled vehicle according to claim 3, wherein the retainer has an oil passage for guiding the lubricating oil supplied from the supply pipe to the bearing.

Images