JP4728057B2 - Dump truck travel drive device - Google Patents

Description

  The present invention relates to a traveling drive device for a dump truck that is preferably used as a large transport vehicle for transporting crushed stones mined in, for example, an open-pit mine, a quarry, a mine, and the like, and in particular, using a planetary gear reduction mechanism. The present invention relates to a traveling drive device for a dump truck configured to increase rotational torque during traveling.

  In general, a large transport vehicle called a dump truck is provided with a vessel (loading platform) that can be raised and lowered on a frame of a vehicle body, and carries a heavy load such as crushed stones on the vessel. .

  For this reason, a travel drive device that travels and drives the drive wheels of a dump truck includes a cylindrical axle housing that is attached to the vehicle body in a non-rotating state, and a drive such as a hydraulic motor that extends in the axial direction in the axle housing. A rotating shaft that is rotationally driven by a power source, a wheel mounting cylinder that is rotatably provided on a front end side outer periphery of the axle housing via a bearing, and is provided between the wheel mounting cylinder and the axle housing. A multi-stage planetary gear reduction mechanism is provided that decelerates and transmits the rotation of the rotation shaft to the wheel mounting cylinder (see, for example, Patent Documents 1 and 2).

  The multi-stage planetary gear speed reduction mechanism decelerates the rotational output of a drive source such as a hydraulic motor and transmits it to a wheel mounting cylinder (wheel), thereby greatly rotating the drive wheels such as the front wheels or rear wheels of the vehicle. Torque is generated to improve the transport performance of the dump truck (vehicle).

JP-A-5-193373 Japanese Patent Laid-Open No. 9-3000984

  By the way, the above-described traveling drive device of the prior art is supplied with lubricating oil to a bearing and a multi-stage planetary gear reduction mechanism provided between the axle housing and the wheel mounting cylinder because a large torque rotational load acts. These are required to be kept in a lubrication state with a lubricating oil.

  However, when a large amount of lubricating oil is stored in the apparatus, heat is generated due to the stirring resistance of the oil, and the load on the apparatus is increased. For this reason, the lubricating oil accommodated in the travel drive device is generally set to the minimum amount of oil (for example, about 1/5 to 1/3 of the internal volume).

  Thereby, the liquid level height of the lubricating oil accommodated in the traveling drive device is lower than the central axis of the device, and is located on the center side of the device, for example, and receives the thrust load from the rotating shaft. It becomes difficult to sufficiently supply the lubricating oil to a thrust receiver or the like. If the operation of the dump truck is continued in this state, there is a problem that the thrust bearing provided in the thrust receiver is worn and damaged at an early stage.

  In particular, when a planetary gear speed reduction mechanism of a type that fixes the carrier in a non-rotatable manner (carrier fixed type) is used, a thrust receiver is provided on the center side of the non-rotated carrier so that the thrust receiver is lubricated. There is a problem that it is difficult to supply oil, and an oil film breakage or the like easily occurs in the thrust receiver at an early stage.

  The present invention has been made in view of the above-described problems of the prior art. The object of the present invention is to provide lubricating oil to a thrust receiver or the like provided on the center side of the carrier even when the carrier of the planetary gear reduction mechanism is non-rotating. It is an object of the present invention to provide a traveling drive device for a dump truck that can be supplied and can reliably improve the durability and life of the entire device.

  In order to solve the above-described problems, the present invention provides a rotating shaft that extends in the axial direction in the axle housing and is driven to rotate by a drive source, and is rotatable through a bearing on the outer peripheral side of the axle housing. And a planetary gear speed reduction mechanism that is provided between the wheel mounting cylinder and the axle housing and transmits the rotation of the rotary shaft to the wheel mounting cylinder at a reduced speed. It is applied to the traveling drive device of the dump truck.

The feature of the configuration adopted by the invention of claim 1 is that the planetary gear reduction mechanism has a non-rotating carrier that rotatably supports a plurality of planetary gears and is provided in the axle housing in a non-rotating state, The carrier is provided with a thrust receiver that comes into contact with the end surface of the rotating shaft and receives a thrust load from the rotating shaft, and a lubricating oil guide that guides the lubricating oil supplied from the outside to the thrust receiver , The thrust receiver is provided on the center side of the carrier and is capable of receiving a thrust load from the rotating shaft, and is rotatably supported by the thrust bearing and abuts against the end surface of the rotating shaft. It is constituted by a disk-shaped rotating body that rotates following the rotation axis .

  According to a second aspect of the present invention, the lubricating oil guide includes a through hole formed in the carrier at a position on the upper side in the upward and downward directions with respect to the thrust receiver, the through hole, and the thrust receiver. And a lubricating oil pocket which is formed on the carrier and collects the lubricating oil through a through hole.

According to a third aspect of the present invention, the thrust bearing is configured by a bearing with a seal that holds therein the lubricating oil guided from the lubricating oil guide .

On the other hand , the feature of the configuration adopted by the invention of claim 4 is that the planetary gear reduction mechanism has a non-rotating carrier that rotatably supports a plurality of planetary gears and is provided in the axle housing in a non-rotating state. The carrier is provided with a thrust receiver that comes into contact with the end surface of the rotating shaft and receives a thrust load from the rotating shaft, and a lubricating oil guide that guides the lubricating oil supplied from the outside to the thrust receiver, The thrust receiver is a cylindrical bush fixed to the carrier so as to be coaxial with the rotation shaft, and is rotatably fitted on the inner peripheral side of the bush. And a disk-like rotating body that rotates following the rotating shaft by contact, and the rotating body is supplied with lubricating oil guided from the lubricating oil guide and a contact surface with the rotating shaft, With the bush Ru near to the formation of the oil passage for lubricating oil supplied to the contact surface.

According to a fifth aspect of the present invention, the lubricating oil guide includes a through hole formed in the carrier at a position on the upper side in the upward and downward directions with respect to the thrust receiver , the through hole, and the thrust receiver. And a lubricating oil pocket which is formed on the carrier and collects the lubricating oil through a through hole .

As described above, according to the first aspect of the present invention, the carrier of the planetary gear speed reduction mechanism is provided in the axle housing in a non-rotating state, and the carrier abuts on the end surface on the front end side of the rotating shaft and is separated from the rotating shaft. A thrust receiver for receiving a thrust load and a lubricant guide for guiding lubricating oil to the thrust receiver are provided , and the thrust receiver is provided on the center side of the carrier and is capable of receiving a thrust load by the rotating shaft. Since it is constituted by a bearing and a disk-like rotating body that is rotatably supported by the thrust bearing and abuts on the end surface on the front end side of the rotating shaft, it rotates following the rotating shaft . The thrust receiver provided on the carrier can guide the lubricating oil supplied from the outside to the thrust receiver by the lubricating oil guide, keep this thrust receiver in a lubricated state, and generate an oil film breakage or the like. It is possible to prevent.

For this reason, even when the amount of lubricating oil accommodated in the travel drive device is set to the minimum required oil amount (for example, about 1/5 to 1/3 of the internal volume), the center side of the device The thrust receiver that is positioned and receives the thrust load from the rotating shaft can be sufficiently supplied with the lubricating oil through the lubricating oil guide, and the thrust receiver can be kept in a lubrication state. As a result, the thrust load from the rotating shaft can be stably received by the thrust receiver, and even when the rotating shaft is formed long, the smooth rotation of the rotating shaft can be compensated, and the durability and life of the device can be improved. Can be improved. In addition, since the thrust receiver is composed of a thrust bearing and a disk-shaped rotating body, the thrust load from the rotating shaft can be rotated by bringing the rotating body into contact with the end surface of the rotating shaft. The body and the thrust bearing can be received smoothly, and even when the rotating shaft is a long shaft, the rotating shaft can be smoothly rotated to ensure stable rotation.

  In the invention according to claim 2, since the lubricating oil guide is constituted by the through hole and the lubricating oil pocket, for example, the lubricating oil scraped up to the upper side of the carrier by the rotation of the ring gear or the like When flowing down along the wall surface or the like, the oil is collected in the lubricating oil pocket through the through hole. And this lubricating oil pocket can supply the lubricating oil collected inside to a thrust receiver, and can maintain this thrust receiver in a lubrication state.

According to the invention described in claim 3, since the thrust bearing is constituted by a bearing with a seal , the lubricating oil guided from the lubricating oil guide to the thrust bearing can be held inside, and the inside of the thrust bearing can be maintained. The lubrication state can be maintained and the occurrence of oil film breakage or the like can be prevented .

Meanwhile, the invention of claim 4, the thrust bearing, since constituted by a cylindrical bush and the rotating body, by abutting the rotating member to the tip end surface of the rotary shaft In this case, the a thrust load from the rotary shaft Ru smoothly can nest in the rotating body and the bushing. The lubricating oil guided from the lubricating oil guide can be supplied to the contact surface with the rotating shaft by the oil passage provided in the rotating body, and the lubricating oil is also supplied to the sliding contact surface between the rotating body and the bush. It is possible to keep the contact surface and the sliding surface in a lubricated state and prevent the occurrence of oil film breakage or the like.

In the invention according to claim 5, since the lubricating oil guide is constituted by the through hole and the lubricating oil pocket , the lubricating oil scraped up to the upper side of the carrier by , for example, rotation of the ring gear or the like is through the through-holes when flowing down along the wall surface or the like ing as collected in the lubricating oil pocket. And this lubricating oil pocket can supply the lubricating oil collected inside to a thrust receiver , and can maintain this thrust receiver in a lubrication state .

  Hereinafter, a dump truck traveling drive apparatus according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings, taking a rear-wheel drive type dump truck as an example.

  Here, FIG. 1 to FIG. 12 show a first embodiment of the present invention. In the figure, reference numeral 1 denotes a dump truck employed in the present embodiment. The dump truck 1 includes a vehicle body 2 having a sturdy frame structure as shown in FIG. 1, and a loading platform mounted on the vehicle body 2 so as to be undulated. And the vessel 3 as a whole.

  The vessel 3 is formed as a large container having a total length of 10 to 13 m (meters) in order to load a large amount of heavy loads such as crushed stones, and its rear bottom is pinned to the rear end side of the vehicle body 2. It is connected via a connecting part 4 or the like so as to be undulated (tilted). Further, on the upper front side of the vessel 3, a flange 3 </ b> A that covers a cabin 5 described later from above is integrally provided.

  A cabin 5 is provided at the front of the vehicle body 2 and is located below the flange 3A. The cabin 5 forms a driver's cab in which a driver of the dump truck 1 gets on and off, and a driver's seat is provided in the cabin. A start switch, an accelerator pedal, a brake pedal, a steering handle, a plurality of operation levers (all not shown), and the like are provided.

  The flange portion 3A of the vessel 3 covers the cabin 5 almost completely from the upper side, thereby protecting the cabin 5 from, for example, rocks and the like, and also in the cabin 5 when the vehicle (dump truck 1) falls. It has a function to protect the driver.

  6 and 6 are left and right front wheels rotatably provided on the front side of the vehicle body 2, and each front wheel 6 constitutes a steering wheel that is steered (steered) by the driver of the dump truck 1. It is. And the front wheel 6 is formed with the tire diameter (outside diameter dimension) which extends to 2-4 m like the rear wheel 7 mentioned later, for example.

  7 and 7 are left and right rear wheels rotatably provided on the rear side of the vehicle body 2, and each rear wheel 7 constitutes a drive wheel of the dump truck 1 and will be described later with reference to FIGS. 3 and 4. The traveling drive device 11 is rotationally driven integrally with the wheel mounting cylinder 19. The rear wheel 7 is detachably fitted to two tires 7A and 7A, rims 7B and 7B disposed inside the tires 7A, and an rim 7B on the axially outer side of the rims 7B. And a wheel cap 7C (see FIG. 1) provided together.

  Reference numeral 8 denotes an engine as a prime mover provided in the vehicle body 2 at the lower side of the cabin 5. The engine 8 is composed of, for example, a large diesel engine or the like, and an alternator 9 as a generator as shown in FIG. Is to drive. The engine 8 also has a function of rotating and driving a hydraulic pump (not shown) serving as a hydraulic source, and supplying and discharging pressure oil to a later-described hoisting cylinder 83, a power steering steering cylinder (not shown), and the like. Have.

  Reference numeral 10 denotes an electric controller that constitutes a control device for the dump truck 1. The electric controller 10 is configured by a switchboard or the like that is positioned on the rear side of the cabin 5 and is erected on the vehicle body 2 as shown in FIG. Yes. The electric controller 10 charges a battery (not shown) with electricity generated by the alternator 9 shown in FIG. 2 and outputs this electricity to an electric motor 17 to be described later. It has a function for feedback control.

  Reference numeral 11 denotes a travel drive device provided on the rear wheel 7 side of the dump truck 1, and the travel drive device 11 includes an axle housing 12, an electric motor 17, a wheel mounting cylinder 19, a speed reduction mechanism 24, and the like, which will be described later. . The travel driving device 11 decelerates the rotation of the electric motor 17 by the speed reduction mechanism 24 and travels and drives the rear wheel 7 as a driving wheel of the vehicle together with the wheel mounting cylinder 19 with a large rotational torque.

  Reference numeral 12 denotes an axle housing for the rear wheel 7 provided on the rear side of the vehicle body 2. The axle housing 12 is a cylindrical body extending in the axial direction between the left and right rear wheels 7, 7, as shown in FIG. It is formed as. The axle housing 12 is provided on an intermediate suspension cylinder 13 attached to the rear side of the vehicle body 2 via a shock absorber (not shown) such as a shock absorber, and on both the left and right sides of the suspension cylinder 13. The motor housing cylinder 14 and the cylindrical spindle 15 which will be described later are configured.

  Reference numerals 14 and 14 denote motor accommodating cylinders as drive source accommodating portions provided at both ends of the suspension cylinder 13, and each of the motor accommodating cylinders 14 is a cylindrical body having a tapered shape as shown in FIGS. The large diameter portion 14A side is detachably fixed to the suspension cylinder 13 shown in FIG. 2 using bolts or the like. Further, as shown in FIGS. 4 and 6, a cylindrical spindle 15 which will be described later is detachably fixed to the motor accommodating cylinder 14 via a bolt 16 or the like, as shown in FIGS. It is a reduction gear housing space A.

  An electric motor 17 (to be described later) serving as a drive source for the rear wheels 7 is accommodated in the motor accommodating cylinder 14. An annular partition plate 14 </ b> C is provided between the motor housing cylinder 14 and the electric motor 17, and the partition plate 14 </ b> C is provided with lubricating oil 100 in an oil reservoir 57, which will be described later, of the electric motor 17. It suppresses leakage to the surroundings.

  Reference numeral 15 denotes a cylindrical spindle that constitutes the opening on the front end side of the axle housing 12, and the cylindrical spindle 15 is composed of a large-diameter stepped cylindrical body having an inner diameter of, for example, about 80 to 100 cm. As shown in FIGS. 3, 4, and 6, the first reduction gear housing space A for housing the first stage planetary gear speed reduction mechanism 25 is formed. The outer peripheral surface of the cylindrical spindle 15 is configured to rotatably support a wheel mounting cylinder 19 on the rear wheel 7 side through bearings 20 and 21 described later.

  Here, an annular convex portion 15A that protrudes radially inward from the inner peripheral surface of the cylindrical spindle 15 is formed integrally with the intermediate portion in the axial direction. The carrier 30 is fixedly attached. The cylindrical spindle 15 has a connecting portion 15B that is connected to the motor housing cylinder 14 via a bolt 16 or the like on one side in the axial direction (base end side), and on the other side (tip side) in the axial direction, As shown in FIGS. 6 and 7, an annular flange portion 15 </ b> C protruding outward in the radial direction is integrally formed.

  A final stage carrier 39 to be described later is fixedly attached to the flange portion 15C of the cylindrical spindle 15. In this case, the outer peripheral side of the flange portion 15C is the largest outer diameter portion having the largest outer diameter size in the cylindrical spindle 15, and the outer diameter of the flange portion 15C is substantially equal to the outer diameter size of the bearings 20 and 21 described later. Dimension is formed.

  Further, as shown in FIGS. 6 and 7, an oil hole 15 </ b> D extending through the annular convex portion 15 </ b> A forward and rearward (axial direction) is formed in the lower position of the cylindrical spindle 15. Then, the lubricating oil 100 supplied into the cylindrical spindle 15 as described later flows through the oil hole 15D before and after the annular convex portion 15A (in the axial direction of the cylindrical spindle 15). As a result, the level of the lubricating oil 100 stored in an oil reservoir 57, which will be described later, is made uniform before and after the oil hole 15D.

  The cylindrical spindle 15 is assembled as a covered cylindrical body having a sturdy structure by being fixedly provided with the carriers 30 and 39 of the planetary gear speed reduction mechanisms 25 and 34 as described later. The mounting cylinder 19 (rear wheel 7) can be supported from the inside with high rigidity (strength). The cylindrical spindle 15 has a function of receiving a rotational reaction force generated in planetary gear speed reduction mechanisms 25 and 34, which will be described later, with sufficient strength via the carriers 30 and 39.

  Here, the first reduction gear housing space A is surrounded by a motor housing cylinder 14 and a cylindrical spindle 15 as shown in FIGS. 4 and 6, and one side (inner side) in the axial direction is a partition plate 14C and an electric motor described later. It is closed by a motor 17 and the other side (outside) in the axial direction is covered with a coupling 33 and the like described later. In the reduction gear housing space A, a first-stage planetary gear speed reduction mechanism 25 described later is housed.

  Reference numeral 17 denotes an electric motor as a drive source which is detachably provided on the motor housing cylinder 14 of the axle housing 12, and the electric motor 17 rotates the left and right rear wheels 7, 7 independently of each other as shown in FIG. For driving, they are mounted in left and right motor housing cylinders 14 and 14 located on both sides of the axle housing 12, respectively.

  Reference numeral 18 denotes a rotating shaft constituting an output shaft of the electric motor 17, and the rotating shaft 18 is driven to rotate in the forward direction or the reverse direction by the electric motor 17. Here, the rotating shaft 18 extends in the reduction gear housing space A in the axial direction from the motor housing cylinder 14 to the cylindrical spindle 15 as shown in FIGS. And the sun gear 26 mentioned later is spline-coupled to the front end side outer periphery of the rotating shaft 18 so that it rotates integrally.

  In this case, the tip end of the rotating shaft 18 extends through the inner peripheral side of the sun gear 26 in the axial direction as shown in FIGS. 6, 7, and 11, and the end surface at the tip end faces a thrust receiver 61 described later. (Facing) When an axial thrust load F is applied to the rotary shaft 18 due to the rotation of the electric motor 17, the thrust receiver 61 receives this thrust load F and restricts the axial displacement of the rotary shaft 18, The rotation of the rotating shaft 18 is smoothed (stabilized).

  Reference numeral 19 denotes a wheel mounting cylinder that rotates integrally with the rear wheel 7 as a wheel. The wheel mounting cylinder 19 constitutes a so-called wheel hub, and rims 7B and 7B of the rear wheel 7 are press-fitted on the outer peripheral side thereof. It is detachably attached using means. As shown in FIG. 6, the wheel mounting cylinder 19 includes a one-side cylinder portion 19 </ b> A extending in the axial direction between the bearings 20 and 21, and an axial direction from the end of the one-side cylinder portion 19 </ b> A toward the ring gear 36 described later. The inner peripheral surface 19B1 is formed as a stepped cylindrical body by the other side cylinder portion 19B formed with an inner diameter larger than the one side cylinder portion 19A.

  In addition, the one side cylinder portion 19A of the wheel mounting cylinder 19 is provided with bearing mounting portions 19C and 19D on the inner peripheral side thereof, with bearings 20 and 21 (described later) fitted and attached as steps. Further, on the inner peripheral side of the one-side cylinder portion 19A, the retainer 73 of the seal device 70, which will be described later, is attached to be positioned between the end surface on the one side in the axial direction and the bearing attachment portion 19C. A retainer mounting portion 19E as an expanding portion is formed.

  Here, the other side cylinder portion 19B of the wheel mounting cylinder 19 has an inner peripheral surface 19B1 having an inner diameter dimension substantially equal to a disk holding cylinder 22 described later. And the other side cylinder part 19B surrounds the collar part 15C etc. of the cylindrical spindle 15 from the radial direction outer side, and has the function to distribute | circulate the lubricating oil 100 smoothly from the reduction gear accommodation space B mentioned later toward the annular space C. I have it.

  In addition, a ring gear 36 and a disk holding cylinder 22 which will be described later are integrally fixed to the other side cylinder portion 19B of the wheel mounting cylinder 19 using a long bolt 43 or the like, whereby the wheel mounting cylinder 19 is attached to the ring gear 36. And rotate together. That is, the wheel mounting cylinder 19 is transmitted via the ring gear 36 the rotation that has become a large torque by decelerating the rotation of the electric motor 17 by the speed reduction mechanism 24. And the wheel attachment cylinder 19 rotates the rear wheel 7 used as a driving wheel of a vehicle with a large rotational torque.

  In this case, the inner peripheral side of the wheel mounting cylinder 19, the disk holding cylinder 22, and the ring gear 36 is formed as a second speed reducer accommodation space B in which a second stage planetary gear speed reduction mechanism 34 described later is accommodated. The second reduction gear housing space B is surrounded by a coupling 33 and the like, which will be described later, with the first reduction gear housing space A located on the one side in the axial direction. Is covered with a carrier 39, an inner cap 42, a seal device 81 and the like, which will be described later.

  Further, the space between the wheel mounting cylinder 19 and the cylindrical spindle 15 is an annular space C that annularly surrounds the outer peripheral side of the cylindrical spindle 15, and the lower part of the annular space C is an oil reservoir 58 to be described later. Thus, the lubricating oil 100 is accommodated. The annular space C is always in communication with the second reduction gear housing space B through a gap in the bearing 21 and the like.

  Further, one side cylinder portion 19A of the wheel mounting cylinder 19 has an inner peripheral surface located between the bearing mounting sections 19C and 19D gradually from the bearing 21 side to the bearing 20 side as shown in FIGS. It is formed as a tapered guide surface (hereinafter referred to as an inclined surface 19F) that expands in diameter. The lubricating oil 100 in the annular space C is guided toward the later-described discharge pipe 79 by the inclined surface 19F. Further, on the one side (inside) in the axial direction of the wheel mounting cylinder 19, a seal device 70 described later is provided at a position between the motor housing cylinder 14, the cylindrical spindle 15 and the wheel mounting cylinder 19 of the axle housing 12. It has been.

  Reference numerals 20 and 21 denote bearings that rotatably support the wheel mounting cylinder 19 on the outer peripheral side of the cylindrical spindle 15, and the bearings 20 and 21 are configured by using, for example, the same tapered roller bearing. Further, the bearings 20 and 21 are disposed apart from each other in the axial direction between the one side cylinder portion 19 </ b> A of the wheel mounting cylinder 19 and the cylindrical spindle 15.

  That is, one bearing 20 is fitted and mounted in a bearing mounting portion 19C of the wheel mounting cylinder 19, and the other bearing 21 is fitted and mounted in a bearing mounting portion 19D of the wheel mounting cylinder 19. Yes. The outer diameter dimensions of the bearings 20 and 21 (inner diameter dimensions of the bearing mounting portions 19C and 19D) are larger than the inner diameter of the one side cylinder portion 19A as shown in FIG. 7, and the inner diameter (inner circumference) of the other side cylinder portion 19B. It is formed smaller than the surface 19B1).

  Reference numeral 22 denotes a disk holding cylinder that constitutes a part of the wheel mounting cylinder 19 together with the ring gear 36. The disk holding cylinder 22 has a ring gear 36, which will be described later, at a position outside the wheel mounting cylinder 19 in the axial direction as shown in FIG. It is attached by being sandwiched, and is detachably fixed to the wheel mounting cylinder 19 using each of the long bolts 43 described later.

  As shown in FIG. 5, a ring-shaped (annular) disk 23 is attached to the disk holding cylinder 22 in a non-rotating state, and the disk 23 is applied with a braking force by a disk brake 56 described later. Is done. That is, the rear wheel 7 and the wheel mounting cylinder 19 rotate integrally with the disk holding cylinder 22 and the disk 23, and the rotation during traveling is stopped (braking) by the braking force applied to the disk 23.

  Reference numeral 24 denotes a speed reduction mechanism provided between the cylindrical spindle 15 and the wheel mounting cylinder 19, and the speed reduction mechanism 24 includes a first stage planetary gear speed reduction mechanism 25 and a second stage planetary gear speed reduction mechanism 34, which will be described later. The rotation of the rotary shaft 18 is decelerated and transmitted to the wheel mounting cylinder 19 on the rear wheel 7 side.

  Reference numeral 25 denotes a first-stage planetary gear speed reduction mechanism provided in the cylindrical spindle 15 of the axle housing 12, and the planetary gear speed reduction mechanism 25 has a rotating shaft as shown in FIG. 3, FIG. 4, FIG. 18 planetary gears 28, 28,... Which are engaged with the sun gear 26 splined to the tip end side of 18, the inner gear 27 A of the sun gear 26 and the ring gear 27, and rotate according to the rotation of the sun gear 26. (See FIGS. 8 and 9) and a carrier 30 described later which rotatably supports each planetary gear 28 via a support pin 29.

  The first-stage ring gear 27 is disposed on the inner peripheral side of the cylindrical spindle 15 so as to be relatively rotatable via a small radial gap (for example, about 2 to 5 mm). The ring gear 27 is formed as a short cylindrical gear that surrounds the sun gear 26, each planetary gear 28, the support pin 29, the carrier 30 and the like from the outside in the radial direction. Inner teeth 27 </ b> A that mesh with each other are provided.

  Here, in the first stage planetary gear speed reduction mechanism 25, the revolution of the planetary gear 28 (rotation of the carrier 30) is restrained by fixing a carrier 30 described later to the cylindrical spindle 15. Then, when the sun gear 26 is integrally rotated by the rotating shaft 18 of the electric motor 17, the first stage planetary gear reduction mechanism 25 converts the rotation of the sun gear 26 into the rotation of the plurality of planetary gears 28.

  The planetary gear speed reduction mechanism 25 in the first stage takes out the rotation (rotation) of each planetary gear 28 as a reduced speed rotation of the ring gear 27 and rotates the rotation of the ring gear 27 through the coupling 33 described later to the second stage. Is transmitted to the planetary gear speed reduction mechanism 34.

  Further, as shown in FIGS. 6 and 7, an oil passage 29A for supplying the lubricating oil 100 is formed in the support pin 29 of each planetary gear 28, and the oil passage 29A is formed inside the cylindrical spindle 15. An after-mentioned conduit 45 extending in the axial direction is connected. Then, the lubricating oil 100 guided from the conduit 45 into the oil passage 29A is supplied so as to be injected toward the bearings 28A of the planetary gear 28, and the tooth surfaces of the bearings 28A and the planetary gear 28 are lubricated. It is something to keep in.

  Reference numeral 30 denotes a first stage carrier used for the first stage planetary gear speed reduction mechanism 25. The carrier 30 is formed of two annularly spaced front and rear parts in the axial direction of the rotary shaft 18 as shown in FIGS. The plate portions 30A and 30B and the substantially fan-shaped connecting portions 30C, 30C,... Integrally connecting the annular plate portions 30A and 30B at three locations in the circumferential direction are roughly configured. Of these, the annular plate portion 30A on one side is formed to have a larger diameter than the annular plate portion 30B on the other side.

  Here, between the annular plate portions 30 </ b> A and 30 </ b> B of the carrier 30, the planetary gears 28 are rotatably mounted via the support pins 29 in the spaces partitioned by the connecting portions 30 </ b> C. Further, as shown in FIGS. 8 and 9, a large number of bolt holes 30D, 30D,... Are formed at intervals on the outer peripheral side of the annular plate portion 30A, and these bolt holes 30D are formed in FIGS. The bolts 31 shown are each fastened (screwed).

  The outer peripheral side of the annular plate portion 30 </ b> A of the carrier 30 is detachably fixed to the annular convex portion 15 </ b> A of the cylindrical spindle 15 using each bolt 31. Accordingly, the first stage carrier 30 is provided in the cylindrical spindle 15 in a non-rotating state, and is accommodated in the reduction gear accommodating space A of the cylindrical spindle 15 together with the plurality of planetary gears 28 and the like.

  Further, the annular plate portions 30A and 30B of the carrier 30 penetrate two axially connecting portions 30C and 30C positioned below a later-described lubricating oil guide 66 as shown in FIGS. An extending oil passage 30E and a liquid passage 30F are formed. The oil passage 30E communicates between a branch pipe 49 and a conduit 50, which will be described later, before and after the carrier 30, and the liquid passage 30F is provided between a brake pipe 53 and 54, which will be described later, before and after the carrier 30. It is something to communicate with.

  Reference numeral 32 denotes an annular bearing mounting portion provided on the center side of the carrier 30. The bearing mounting portion 32 is integrated with the inner peripheral side of the annular plate portion 30B of the carrier 30 as shown in FIGS. Is formed. A thrust bearing 62 of a thrust receiver 61, which will be described later, is fitted and mounted in the bearing mounting portion 32. The annular plate portion 30 </ b> B of the carrier 30 is provided with a later-described lubricating oil guide 66 that guides the lubricating oil to the thrust bearing 62.

  Reference numeral 33 denotes a coupling as a rotation transmitting member that rotates integrally with the first stage ring gear 27, and the coupling 33 is provided between the first stage planetary gear reduction mechanism 25 and the second stage planetary gear reduction mechanism 34. The outer peripheral side is coupled to the first stage ring gear 27 by means such as a spline.

  Further, the inner peripheral side of the coupling 33 is coupled to a second stage sun gear 35 described later by means such as a spline. The coupling 33 transmits the rotation of the first-stage ring gear 27 to the second-stage sun gear 35 and rotates the sun gear 35 integrally with the ring gear 27 at the same speed. The coupling 33 has a plurality of oil holes through which the lubricating oil 100 in the first reduction gear housing space A flows toward the second reduction gear housing space B before and after the coupling 33 (see FIG. (Not shown) may be formed.

  Reference numeral 34 denotes a second-stage planetary gear reduction mechanism that is the final stage employed in the present embodiment, and the planetary gear reduction mechanism 34 is disposed between the cylindrical spindle 15 and the wheel mounting cylinder 19 in the first-stage planetary gear. It is arranged via a speed reduction mechanism 25 and, together with the first stage planetary gear speed reduction mechanism 25, reduces the rotation of the rotary shaft 18 and generates a large rotational torque in the wheel mounting cylinder 19.

  In this case, the planetary gear speed reduction mechanism 34 at the second stage is arranged so as to be coaxial with the rotary shaft 18 and rotates integrally with the coupling 33, and the internal teeth 36 </ b> A of the sun gear 35 and the ring gear 36. (See FIG. 7) and, for example, three planetary gears 37 (only one is shown) that rotate according to the rotation of the sun gear 35, and each planetary gear 37 is rotatably supported via a support pin 38. It is comprised by the carrier 39 grade | etc.,.

  The outer periphery of the second stage carrier 39 is fixed to the flange 15C of the cylindrical spindle 15 in a non-rotating state and detachably using a bolt 40 (see FIG. 7). As a result, the carrier 39 also serves as a lid that covers the reduction gear housing space A from the outside at the open end of the cylindrical spindle 15. Further, as shown in FIG. 7, a bearing 41 and the like are provided on the inner peripheral side of the carrier 39, and this bearing 41 supports the sun gear 35 between the coupling 33 so as to be rotatable from both sides in the axial direction. Yes.

  On the other hand, the second-stage ring gear 36 is formed as a short cylindrical body that surrounds the sun gear 35, the planetary gear 37, the support pin 38, the carrier 39 and the like from the outside in the radial direction, and the wheel mounting cylinder 19 and the disk holding cylinder 22. Are fixed integrally using a long bolt 43 described later. Then, on the inner peripheral side of the ring gear 36, internal teeth 36A (see FIG. 7) that mesh with the planetary gears 37 are formed.

  Here, in the second stage planetary gear speed reduction mechanism 34 as the final stage, the revolution of the planetary gear 37 (rotation of the carrier 39) is restrained by fixing the carrier 39 to the cylindrical spindle 15. Then, when the sun gear 35 rotates together with the coupling 33, the planetary gear speed reduction mechanism 34 at the second stage converts the rotation of the sun gear 35 into the rotation of the plurality of planetary gears 37, and this rotation (rotation). Is taken out from the ring gear 36 as a reduced speed rotation.

  That is, the ring gear 36 in this case is provided integrally with the wheel mounting cylinder 19 together with the disk holding cylinder 22. The wheel mounting cylinder 19 on the side of the rear wheel 7 is transmitted with a large output rotational torque reduced in two stages by the first stage planetary gear reduction mechanism 25 and the second stage planetary gear reduction mechanism 34. It is.

  Further, as shown in FIG. 7, an oil passage 38 </ b> A is formed in the support pin 38 of each planetary gear 37, and a later-described supply pipe 51 is connected to the oil passage 38 </ b> A from the outside of the carrier 39. Then, the lubricating oil 100 guided from the supply pipe 51 into the oil passage 38A is supplied so as to be injected toward the bearings 37A of the planetary gears 37, and the tooth surfaces of the bearings 37A and the planetary gears 37 are lubricated. It is something to keep in.

  On the other hand, the carrier 39 of the planetary gear speed reduction mechanism 34 is formed with an oil groove 39A extending upward and downward along the flange portion 15C of the cylindrical spindle 15 as shown in FIG. The radially inner side and the outer side of the carrier 39 are always in communication with each other through the oil groove 39A, and the lubricating oil 100 supplied into the first and second reduction gear housing spaces A and B is in the oil groove 39A. It distribute | circulates toward the position which becomes the lower side of the wheel attachment cylinder 19 via.

  That is, the oil groove 39 </ b> A is formed as an oil passage for connecting oil reservoirs 57, 58 described later between the cylindrical spindle 15 and the carrier 39, and is stored in the cylindrical spindle 15 of the oil reservoirs 57, 58. The lubricating oil 100 flows down along the oil groove 39A on the end face side of the flange portion 15C. The liquid level of the lubricating oil 100 is made uniform by the oil groove 39A in the cylindrical spindle 15 (oil sump 57) and in the wheel mounting cylinder 19 (oil sump 58).

  Reference numeral 42 denotes an inner cap that covers the inner peripheral side of the carrier 39. The inner cap 42 is detachably provided on the inner peripheral side of the carrier 39 via a bolt or the like as shown in FIG. The carrier 39 is held in a retaining state. The inner cap 42 covers the opening end side of the cylindrical spindle 15 together with the carrier 39 to prevent the lubricating oil 100 and the like in the second reduction gear housing space B from leaking from the inside of the carrier 39. is there.

  43 are long bolts which are fixing means for fixing the disk holding cylinder 22 to the wheel mounting cylinder 19, and these long bolts 43 are arranged in the circumferential direction of the disk holding cylinder 22 as shown in FIG. Are attached at predetermined intervals. As shown in FIG. 6, the long bolt 43 is connected to the disk holding cylinder 22 and the ring gear 36 in addition to the wheel mounting cylinder 19 with the ring gear 36 sandwiched between the wheel mounting cylinder 19 and the disk holding cylinder 22. It is detachably fixed to the side tube portion 19B.

  Reference numeral 44 denotes a first lubricating oil supply path provided as a lubricating oil supply means provided in the axle housing 12, and this lubricating oil supply path 44 includes a conduit 45 extending in the axial direction in the cylindrical spindle 15 and each planet. The oil passage 29A and the like are formed in the support pin 29 of the gear 28. One side (base end side) of the conduit 45 is connected to the lubricating oil supply pipe 46 at the position of the partition plate 14C shown in FIG. It is connected to a lubricating oil pump (not shown).

  Further, the other side (tip side) of the conduit 45 is connected to an oil passage 29A of the support pin 29, and in this oil passage 29A, the lubricating oil discharged from the lubricating oil pump is connected to the supply pipe 46 and the conduit 45. Led through. The lubricating oil 100 in the oil passage 29A is supplied so as to be injected toward the bearings 28A of the planetary gear 28, and the tooth surfaces of the bearings 28A and the planetary gear 28 are kept in a lubrication state.

  Note that, for example, three planetary gears 28 are attached to the first stage carrier 30 via support pins 29, and other planetary gears 28 not shown in FIG. Lubricating oil is similarly supplied from a position via a branch pipe (not shown) branched by a joint 48 described later.

  Reference numeral 47 denotes a second lubricating oil supply path serving as a lubricating oil supply means for supplying the lubricating oil 100 to the second stage planetary gear speed reduction mechanism 34. The lubricating oil supply path 47 is connected to the conduit 45 as shown in FIG. A branch pipe 49 branched from the middle position of the branch pipe 49 through the joint 48, an oil passage 30E (see FIG. 8) of the carrier 30 to which the distal end side of the branch pipe 49 is connected, and the branch pipe 49 via the oil passage 30E. And a supply pipe 51 and the like which will be described later.

  Here, the lubricating oil conduit 50 extends in the axial direction with a gap inside the second stage sun gear 35 as shown by a two-dot chain line in FIGS. 6 and 7, and the tip end side is attached to the inner cap 42. Yes. A supply pipe 51 (described later) is connected to the end of the conduit 50 drawn out from the inner cap 42. The proximal end side of the conduit 50 is connected to the branch pipe 49 via the oil passage 30E or the like drilled in the first stage carrier 30 as described above.

  , 51 are supply pipes as other conduits for supplying the lubricating oil 100 to the second stage planetary gear speed reduction mechanism 34, and these supply tubes 51 are outside the carrier 39 as shown in FIG. It is connected to an oil passage 38A (see FIG. 7) of each support pin 38 at a position. Further, these supply pipes 51 are connected to a conduit 50 or the like indicated by a two-dot chain line in FIG. 7, and lubricating oil is supplied from the branch pipe 49 side. The lubricating oil 100 is supplied in an injection state into the oil passages 38 </ b> A of the support pins 38 through the supply pipes 51.

  52 is a return pipe provided outside the inner cap 42. This return pipe 52 is connected to the most downstream side of the supply pipe 51 as shown in FIG. 7 to return to the inside of the inner cap 42. The return oil (lubricating oil) is supplied to the bearing 41 and the like between the inner cap 42 and the sun gear 35, and then gradually falls and stored in an oil reservoir 58 described later.

  A brake pipe 53 is disposed in the cylindrical sun gear 35 with a gap and extends in the axial direction. Like the lubricating oil conduit 50, the brake pipe 53 is attached to the inner cap 42 from the inner cap 42. Has been pulled out. Further, the base end side (one side) of the brake pipe 53 extends toward the first-stage carrier 30 and is connected to another brake pipe 54 via a liquid passage 30F (see FIG. 8) of the carrier 30 or the like. Yes.

  As shown in FIGS. 4 and 6, the other brake pipe 54 extends in the reduction gear housing space A of the cylindrical spindle 15 in the axial direction, and its base end side is a hydraulic pressure for a brake mounted on the vehicle. It is connected to a master cylinder (not shown) via a control valve or the like. When the brake is operated, the brake fluid pressure from the master cinder is supplied to the brake piping 53 side through the brake piping 54 and the fluid passage 30F of the carrier 30 (see FIG. 8).

  Further, the front end side of the brake pipe 53 drawn out from the inner cap 42 is connected to a total of three branch pipes 55, 55,... (See FIG. 5) made of, for example, a flexible hose. These branch pipes 55 supply the brake fluid pressure from the brake pipe 53 side to each disk brake 56 described later.

  56, 56,... Are a plurality of disc brakes that constitute a brake means together with the disc 23. Each disc brake 56 is externally (decelerated) on the second stage carrier 39 as a final stage as shown in FIG. It is attached using bolts 56A and the like from the outside of the machine housing space A). Further, a total of three disc brakes 56 are provided at intervals in the circumferential direction of the disc 23 as shown in FIG.

  The disc brake 56 clamps the disc 23 from both sides in the axial direction by supplying the brake fluid pressure from the master cylinder via the brake pipes 54 and 53 and the branch pipes 55. A braking force is applied to the wheel mounting cylinder 19 (rear wheel 7) that rotates integrally.

  57 is an oil sump provided in the cylindrical spindle 15, and this oil sump 57 is formed at a position below the first reduction gear housing space A described above, and is a first stage planetary gear speed reduction mechanism. For example, the lubricating oil 100 supplied to the sun gear 26 and the planetary gears 28 constituting the gear 25 is accommodated at the liquid level shown in FIG. 6, for example.

  58 is an oil sump provided in the wheel mounting cylinder 19, and this oil sump 58 is formed at a position below the second reduction gear housing space B and the annular space C described above. The lubricating oil 100 supplied to the sun gear 35 and each planetary gear 37 constituting the planetary gear speed reduction mechanism 34 in the final stage) is accommodated together with the oil reservoir 57 in the cylindrical spindle 15.

  In this case, the lubricating oil 100 in the oil reservoirs 57, 58 has a liquid surface height (below the central axis (conduit 45) of the planetary gear 28 and the support pin 29 in order to keep the oil liquid stirring resistance small. For example, it is accommodated with the liquid level shown in FIG. That is, the oil amount of the lubricating oil 100 accommodated in the oil reservoirs 57 and 58 is set to a necessary minimum oil amount (for example, about 1/5 to 1/3 of the internal volume).

  As a result, the lubricating oil 100 in the oil reservoirs 57, 58 causes the rotational resistance (viscosity resistance of the lubricating oil) to be applied to the ring gears 27, 36 of the planetary gear reduction mechanisms 25, 34, the rotating planetary gears 28, 37, the coupling 33, and the like. , And the bearings 20 and 21 and the ring gears 27 and 36 are always kept in a lubricated state.

  59 is a drain hole formed in the lowermost part of the wheel mounting cylinder 19, and this drain hole 59 extends in the axial direction through the ring gear 36 and the disk holding cylinder 22, as shown in FIGS. The tip side is detachably closed by a plug 60. When the plug 60 is removed, the lubricating oil 100 accumulated in the oil reservoirs 57 and 58 (the wheel mounting cylinder 19) is discharged to the outside through the drain hole 59.

  Reference numeral 61 denotes a thrust receiver that receives a thrust load from the rotary shaft 18. The thrust receiver 61 is located on the center side of the carrier 30 (on the axis OO in FIG. 10) as shown in FIGS. And provided on the inner peripheral side of the annular plate portion 30B via an annular bearing mounting portion 32. The thrust receiver 61 includes a later-described thrust bearing 62 and a rotating body 65 disposed coaxially with the rotating body 65 (on the axis OO).

  A thrust bearing 62 is mounted on the inner peripheral side of the annular plate portion 30B via a bearing mounting portion 32. The thrust bearing 62 is a ball bearing or the like capable of receiving a thrust load as shown in FIGS. Used as a bearing with a seal by a seal body 63 described later. The thrust bearing 62 is rotatable via an outer ring 62A fitted in the annular bearing mounting portion 32 and a plurality of balls 62B, 62B,... As rolling elements on the inner peripheral side of the outer ring 62A. The inner ring 62C is provided.

  Reference numeral 63 denotes an annular seal body provided between the outer ring 62A and the inner ring 62C of the thrust bearing 62. The seal body 63 is formed of, for example, an annular packing material, and is opposite to a later-described lubricating oil pocket 69. Is mounted in the thrust bearing 62 at a position where The sealing body 63 holds the lubricating oil 100 supplied from the lubricating oil pocket 69 to each ball 62B and the like between the outer ring 62A and the inner ring 62C, and the lubricating oil 100 at this time leaks out to the sun gear 26 side. It is a thing that suppresses.

  Reference numeral 64 denotes a stopper that holds the thrust bearing 62 in a retaining state in the bearing mounting portion 32. The stopper 64 is configured by, for example, a C-shaped retaining ring, and is attached to the inner peripheral side of the bearing mounting portion 32. Installed as possible. The stopper 64 is in contact with the outer ring 62A of the thrust bearing 62 and restricts axial displacement or the like of the thrust bearing 62 in the bearing mounting portion 32.

  65 is a stepped disk-like rotating body rotatably supported by the thrust bearing 62 in the bearing mounting portion 32 of the carrier 30. The rotating body 65 is provided with a means such as press fitting into the inner ring 62C of the thrust bearing 62. And is rotated integrally with the inner ring 62C via the balls 62B with respect to the outer ring 62A. As shown in FIG. 11, the rotating body 65 has a convex surface portion 65A that abuts the end surface of the rotating shaft 18, and the convex surface portion 65A applies the thrust load F from the rotating shaft 18 to the thrust bearing 62 and the like. Accept through.

  That is, when an axial thrust load F is applied to the rotating shaft 18 by the rotation of the electric motor 17, the end surface on the front end side of the rotating shaft 18 contacts the convex surface portion 65A of the rotating body 65, and the rotating body 65 is , Following the rotation shaft 18 and rotating. The rotating body 65 receives the thrust load F at this time on the convex surface portion 65A side and regulates the axial displacement of the rotating shaft 18.

  Reference numeral 66 denotes a lubricant guide provided in the annular plate portion 30B of the carrier 30. The lubricant guide 66 is positioned above the thrust receiver 61 and has a through hole 67 formed in the annular plate portion 30B. It is comprised by the below-mentioned lubricating oil pocket 69 arrange | positioned between the hole 67 and the thrust receiver 61. FIG.

  The lubricating oil guide 66 is lubricated when, for example, the lubricating oil scraped up from the oil reservoir 57 by the ring gear 27 and attached to the annular plate portion 30B of the carrier 30 flows down due to natural fall (self-weight) or the like. Oil is guided to a thrust receiver 61 through a through hole 67 and a lubricating oil pocket 69 described later, and the thrust receiver 61 is kept in a lubrication state.

  Here, the through hole 67 of the lubricant guide 66 is formed as a substantially U-shaped stepped opening as shown in FIGS. 8 to 11, and the through hole 67 is formed at a position above the lubricant pocket 69. Rib-shaped protrusions 68 are provided so as to surround. The rib-shaped protrusion 68 guides the lubricating oil adhering to the wall surface of the carrier 30 in the directions indicated by arrows D and E in FIG. 11 and flows down into the lubricating oil pocket 69 (described later) through the through hole 67 ( Dripping).

  Reference numeral 69 denotes a lubricating oil pocket for storing lubricating oil to be supplied to the thrust receiver 61. The lubricating oil pocket 69 is integrally formed with the annular plate portion 30B of the carrier 30 as shown in FIGS. 8 to 11, and the annular plate portion 30B. It protrudes (bulges out) in the form of a pocket from the outer surface of the. The lubricating oil pocket 69 includes a lower bulging cover portion 69A formed as a substantially circular lid so as to surround the bearing mounting portion 32 (thrust receiver 61) of the carrier 30 from the outside, and the bulging portion. In order to collect lubricating oil in the cover portion 69A, the cover portion 69A is constituted by a substantially rectangular bulging window portion 69B integrally formed on the upper side of the bulging cover portion 69A.

  Here, the bulging window portion 69 </ b> B of the lubricating oil pocket 69 is disposed at a lower position of the through hole 67 with an opening width substantially equal to the through hole 67. Also, the lubricating oil pocket 69 is provided with a substantially rectangular communication hole 69C at a position inside the bulging window 69B. The communication hole 69C is located above and below the bearing mounting portion 32 of the carrier 30. It is formed by cutting out the upper part of the direction into a square shape.

  The lubricating oil pocket 69 takes in the lubricating oil that flows down (drops) along the wall surface of the carrier 30 in the directions indicated by arrows D and E in FIG. Oil is guided into the bulging cover portion 69A through the communication hole portion 69C and collected inside. In this case, as shown in FIG. 11, the bulging cover portion 69A covers the thrust bearing 62 and the like of the thrust receiver 61 with a gap from the outside in the axial direction, and collects the lubricating oil 100 collected inside the outer ring 62A and the inner ring of the thrust bearing 62. Supply (grease) between 62C and the like.

  In addition, a circular punching hole 69D is formed at a position facing the rotating body 65 on the center side of the bulging cover portion 69A (on the axis OO in FIG. 10). The carrier 30 is provided in order to improve the molding workability when the carrier 30 is integrally molded with the lubricating oil pocket 69. The punching hole 69D is not necessarily provided. In some cases, the punching hole 69D may be eliminated from the bulging cover portion 69A.

  70 is a sealing device that seals the space between the cylindrical spindle 15 and the wheel mounting cylinder 19 in a liquid-tight manner, and the sealing device 70 is constituted by a so-called floating seal as shown in FIGS. 4, 6, and 12. . The sealing device 70 prevents the lubricating oil 100 accommodated in the annular space C between the cylindrical spindle 15 and the wheel mounting cylinder 19 from leaking to the outside of a retainer 71 described later, and earth and sand, rainwater, etc. Intrusion into the annular space C is prevented.

  Here, as shown in FIG. 12, the sealing device 70 includes a fixed-side retainer 71 sandwiched between the motor housing cylinder 14 of the axle housing 12 and the cylindrical spindle 15 via a bolt 16 and the like, and a wheel mounting cylinder. A retainer 73 on the rotating side, which is located in the retainer mounting portion 19E of 19 and is attached to an end face on one axial side via a bolt 72 or the like, and a pair of O as a seal member between the retainers 71, 73 The ring 74 is composed of a pair of seal rings 75 and 75 disposed so as to be opposed to each other in the axial direction.

  The sealing device 70 elastically deforms the pair of O-rings 74 between the retainers 71 and 73 and the seal rings 75 and 75 to seal between the retainers 71 and 73 and the respective O-rings 74, and the O-ring. An axial pressing force is applied to each seal ring 75 with an elastic restoring force of 74. As a result, the pair of seal rings 75, 75 come into sliding contact with each other in the axial direction, and seal the sliding contact surfaces of both of them in a liquid-tight manner.

  Further, as shown in FIG. 12, the fixed-side retainer 71 has a cylindrical portion 71A fitted to the outer peripheral side of the cylindrical spindle 15, and projects inward in the radial direction from the base end side of the cylindrical portion 71A. 14 and an annular protrusion 71B sandwiched between the cylindrical spindle 15 and an annular flange portion 71D that protrudes radially outward from the proximal end side of the cylindrical portion 71A and is integrally formed with a holding portion 71C of an O-ring 74. It is comprised by.

  An annular protrusion 71B of the retainer 71 is connected to a shim plate, which will be described later, on the end surface on one axial side (base end side) of the cylindrical spindle 15 when the cylindrical portion 71A is fitted to the outer peripheral side of the cylindrical spindle 15. 77, and is fixed to the end surface side of the cylindrical spindle 15 by a bolt 76. The retainer 71 constitutes a seal mounting body that is a part of a lubricating oil discharge portion 78 described later, and a discharge tube 79 described later is connected to the flange portion 71D.

  Reference numeral 77 denotes a shim plate sandwiched between a fixed-side retainer 71 and the cylindrical spindle 15 using a bolt 76, and the shim plate 77 extends in the circumferential direction along the proximal end surface of the cylindrical spindle 15. It is formed as an annular flat plate. The shim plate 77 variably adjusts the distance S (see FIG. 12) between the annular protrusion 71B of the retainer 71 and the end surface of the cylindrical spindle 15 according to the thickness or number of the shim plates 77.

  In this case, the cylindrical portion 71A of the retainer 71 fitted to the outer peripheral side of the cylindrical spindle 15 is in contact with the inner ring of the bearing 20 at its distal end side, and the axial set load (thrust load) on the bearing 20 is applied to the shim plate. It is variably adjusted in accordance with the thickness or the number of sheets. Further, the other bearings 21 arranged between the cylindrical spindle 15 and the wheel mounting cylinder 19 are also in contact with the flange 15C side of the cylindrical spindle 15 as shown in FIG. The set load (thrust load) of the bearing 21 is variably adjusted according to the thickness or number of shim plates 77.

  Reference numeral 78 denotes a lubricating oil discharge portion serving as a lubricating oil discharge means for sucking out and discharging the lubricating oil 100 in the oil reservoirs 57 and 58 to the outside of the wheel mounting cylinder 19, and the lubricating oil discharge portion 78 is used for the retainer 71 described above. It is configured by connecting a discharge pipe 79 to the flange portion 71D. Here, the lubricating oil discharge pipe 79 is disposed at the lowest position between the cylindrical spindle 15 and the wheel mounting cylinder 19.

  The discharge pipe 79 is supplied with the lubricating oil 100 supplied in the first and second reduction gear housing spaces A and B and the annular space C and stored in the oil reservoirs 57 and 58, for example, in-vehicle lubrication. The oil is discharged while being sucked in the direction of arrow G in FIGS. 6 and 12 toward the outside of the annular space C by an oil pump or the like.

  In this case, the discharge pipe 79 is attached to the retainer 71 with one end portion serving as a suction port 79A, and this suction port 79A is equivalent to the roller (roller) of the bearing 20 below the cylindrical spindle 15. It is arranged at the height position. The discharge pipe 79 is drawn out of the axle housing 12 (motor housing cylinder 14) from the position of the suction port 79A via the retainer 71. The other end 79B, which is the downstream side of the discharge pipe 79, is attached to the large-diameter portion 14A side of the motor housing cylinder 14, and other pipes, filters, and the like from the suspension cylinder 13 side of the axle housing 12 shown in FIG. It is connected to the suction side of the lubricating oil pump via a cooling device (both not shown).

  Further, a detector (not shown) for detecting the level of the lubricating oil 100 accommodated in the oil reservoirs 57 and 58, for example, is provided on the small diameter portion 14B side of the motor accommodating cylinder 14. When the liquid level in the oil reservoirs 57, 58 becomes higher than a predetermined reference liquid level, the lubricating oil 100 in the oil reservoirs 57, 58 is discharged to the outside through, for example, the drain hole 59 or the like. The

  As a result, the lubricating oil 100 in the oil reservoirs 57 and 58 becomes the liquid level illustrated in FIG. 6 (e.g., equivalent to or slightly lower than the central axis of the planetary gear 28 and the support pin 29). Liquid level). The lubricating oil discharged from the discharge pipe 79 is supplied to the supply pipe 46 side again after removing foreign matters by the filter and being cooled by the cooling device.

  Reference numeral 80 denotes an air discharge pipe provided on the partition plate 14C of the motor housing cylinder 14. The air discharge pipe 80 is attached to the upper side of the partition plate 14C as shown in FIG. Exhaust air to the outside. Thereby, the inside of the cylindrical spindle 15 and the wheel mounting cylinder 19 is always kept at a pressure equal to or lower than the atmospheric pressure.

  Reference numeral 81 denotes another seal device disposed at a position on the outer side in the axial direction of the wheel mounting cylinder 19, and the seal apparatus 81 is configured as a so-called floating seal, and as shown in FIGS. And a final stage (second stage) carrier 39 via a stationary retainer 81A and the like. This sealing device 81 is also configured in substantially the same manner as the sealing device 70 shown in FIGS. 6 and 12 disposed on one side (inside) in the axial direction of the wheel mounting cylinder 19, and is in the second reduction gear housing space B. This prevents the lubricating oil 100 from leaking to the outside from between the disk holding cylinder 22 and the retainer 81A on the carrier 39 side, and prevents the entry of external earth and sand, rainwater, and the like.

  82 is a wedge member that removably fixes the rear wheel 7 to the outer peripheral side of the wheel mounting cylinder 19, and the wedge member 82 is arranged from the outer side in the axial direction of the wheel mounting cylinder 19 as shown in FIGS. 3 and 4. 7 is fitted between the rim 7B and the wheel mounting cylinder 19, and the rear wheel 7 is prevented from being pulled out of the wheel mounting cylinder 19 and held in a rotating state.

  For this reason, ten or more wedge members 82 are provided at intervals in the circumferential direction of the wheel mounting cylinder 19, and the rear wheel 7 is removed from the wheel mounting cylinder 19 by detaching these wedge members 82. is there. 6 and 7 show a state in which the rear wheel 7 and the wedge member 82 are removed from the outer peripheral side of the wheel mounting cylinder 19.

  83 is a hoisting cylinder for hoisting the vessel 3 of the dump truck 1 shown in FIG. 1, and the hoisting cylinder 83 is located between the front wheel 6 and the rear wheel 7 as shown in FIG. It is arranged on both the left and right sides. The undulating cylinder 83 expands and contracts in the upward and downward directions when pressure oil is supplied and discharged from the outside, and undulates (tilts) the vessel 3 around the pin coupling portion 4 on the rear side.

  Reference numeral 84 denotes a hydraulic oil tank, and the hydraulic oil tank 84 is located below the vessel 3 and attached to the side surface of the vehicle body 2 as shown in FIG. The hydraulic oil stored in the hydraulic oil tank 84 is supplied to and discharged from the hoisting cylinder 83 and the power steering steering cylinder as pressure oil by the hydraulic pump.

  The traveling drive device 11 of the dump truck 1 according to the present embodiment has the above-described configuration, and the operation thereof will be described next.

  First, when a driver who has entered the cabin 5 of the dump truck 1 starts the engine 8 shown in FIG. 2, a hydraulic pump (not shown) serving as a hydraulic source is rotationally driven and power is generated by the alternator 9. The electricity is supplied to the electric controller 10 and the like while the electricity is charged in the battery and the like.

  When the vehicle is driven to travel, a drive current is supplied from the electric controller 10 to each electric motor 17 on the rear wheel 7 side. At this time, the electric controller 10 determines the rotational speeds of the left and right electric motors 17 and 17. Individual feedback control. As a result, the left and right rear wheels 7 and 7 serving as drive wheels of the vehicle are driven to rotate independently of each other, and are driven at the same rotational speed when traveling straight ahead.

  That is, the traveling drive device 11 provided on the rear wheel 7 side of the dump truck 1 reduces the rotation of the electric motor 17 (rotating shaft 18) by, for example, about 30 to 40 by the multi-stage planetary gear reduction mechanisms 25 and 34. The rear wheel 7 serving as a driving wheel is driven to travel with a large rotational torque together with the wheel mounting cylinder 19. The left and right rear wheels 7 are driven by the left and right electric motors 17 at independent rotation speeds.

  Further, in the first-stage and second-stage planetary gear speed reduction mechanisms 25, 34, etc., the lubricating oil 100 discharged from the on-vehicle lubricating oil pump (supply source) is supplied with the first lubrication through the supply pipe 46 shown in FIG. The oil is supplied to the oil supply path 44 and the second lubricating oil supply path 47, and the sun gears 26 and 35, the planetary gears 28 and 37, etc. are kept in a lubrication state. Then, the lubricating oil 100 at this time is sequentially dropped and stored in the lower oil reservoirs 57 and 58 by the action of gravity while lubricating the respective tooth surfaces and the like.

  In this case, in the first lubricating oil supply passage 44, the lubricating oil 100 guided from the supply piping 46 through the conduit 45 into the oil passage 29 </ b> A of the support pin 29 is directed toward the bearings 28 </ b> A of the planetary gears 28. Let spray. Then, each planetary gear 28 that rotates can guide the lubricating oil 100 to the outside in the radial direction by the centrifugal force due to the rotation, and keep the meshing surfaces and the like of the planetary gear 28, the sun gear 26, and the ring gear 27 in a lubricated state. it can.

  Further, in the second lubricating oil supply passage 47, as illustrated in FIG. 6, the branch pipe 49 branched from the middle position of the conduit 45 through the joint 48 and the oil passage 30E in the carrier 30 (FIGS. 8 and 9). The lubricating oil 100 introduced into the oil passage 38A of the support pin 38 through the conduit 50 (see FIGS. 7 and 8), the supply pipes 51 (see FIG. 5), and the like. Inject toward. These planetary gears 37 can guide the lubricating oil 100 to the outside in the radial direction by the centrifugal force generated by the rotation, and keep the meshing surfaces of the planetary gears 37, the sun gear 35, the ring gear 36, and the like in a lubricated state. .

  A return pipe 52 is connected to the most downstream side of the supply pipe 51 shown in FIG. 5, and excess lubricating oil in the supply pipe 51 is returned to the inside of the inner cap 42 by the return pipe 52. The return oil (lubricating oil) is supplied to the bearing 41 and the like between the inner cap 42 and the sun gear 35 and then gradually dropped into the oil reservoir 58 and stored.

  Further, the lubricating oil 100 accommodated in the oil reservoirs 57 and 58 is sequentially lifted upward by the internal teeth 27A and 36A of the rotating first-stage and second-stage ring gears 27 and 36, and the planetary gear reduction. It is possible to perform scraping lubrication or the like for the mechanisms 25 and 34. Then, the lubricating oil 100 stored in the oil reservoir 57 in the first reduction gear housing space A (cylindrical spindle 15) is positioned below the first stage carrier 30 and is annular in the cylindrical spindle 15. It is possible to circulate before and after the carrier 30 through the oil hole 15D formed in the convex portion 15A, and to make the liquid level always uniform before and after the oil hole 15D.

  Further, between the last stage carrier 39 and the flange 15C of the cylindrical spindle 15, the end surface of the carrier 39 is cut upward and downward to extend downward along the flange 15C of the cylindrical spindle 15. An oil groove 39A is provided. Since the lubricating oil 100 stored in the cylindrical spindle 15 out of the oil reservoirs 57 and 58 flows down along the oil groove 39A on the end surface side of the flange portion 15C, the liquid level is set to the cylindrical shape. The inside of the spindle 15 and the wheel mounting cylinder 19 can be made uniform by the oil groove 39A.

  On the other hand, between the cylindrical spindle 15 and the wheel mounting cylinder 19, a seal device 70 for sealing the lubricating oil 100 is provided in the annular space C. A retainer 71 serving as a seal mounting body of the seal device 70 is provided in the retainer 71. In addition, a discharge pipe 79 of the lubricating oil discharge portion 78 is connected to the lowest part of the cylindrical spindle 15 and the wheel mounting cylinder 19. And the edge part used as the downstream of the discharge pipe 79 is connected to the suction side of the said lubricating oil pump through a filter, a cooling device (all are not shown), etc.

  Thus, when this lubricating oil pump is operated, the lubricating oil 100 discharged from the lubricating oil pump is supplied to the first and second planetary gear reduction mechanisms 25, 34, etc., as the first and second lubricating oils. The lubricating oil 100 that can be supplied from the supply passages 44 and 47 and stored in the oil reservoirs 57 and 58 can be forcibly discharged from the discharge pipe 79 to the outside. At this time, foreign matter in the discharged oil (lubricating oil) can be removed by filtering with the filter, and the lubricating oil can be cooled by the cooling device.

  By the way, the lubricating oil 100 accommodated in the travel drive device 11 (for example, the cylindrical spindle 15) is set to a minimum required amount of oil (for example, about 1/5 to 1/3 of the internal volume). Therefore, for example, it is difficult to sufficiently supply the lubricating oil 100 in the oil reservoir 57 to the thrust receiver 61 or the like that is located on the center side of the apparatus and receives the thrust load F from the rotating shaft 18. In particular, in the first stage planetary gear speed reduction mechanism 25, the thrust receiver 61 is provided on the center side of the non-rotating carrier 30, so that it is difficult to supply the lubricating oil to the thrust receiver 61.

  Therefore, according to the present embodiment, the lubricant guide 66 is provided in the annular plate portion 30B of the carrier 30, and the lubricant guide 66 is formed in the annular plate portion 30B so as to be located on the upper side of the thrust receiver 61. A through hole 67 and a lubricating oil pocket 69 which is disposed between the through hole 67 and the thrust receiver 61 and collects and collects the lubricating oil 100 therein are configured.

  For this reason, for example, when the lubricating oil scraped up from the oil reservoir 57 by the rotation of the ring gear 27 and the like to the upper side of the carrier 30 flows down in the direction indicated by the arrow D in FIG. The oil is collected in the bulging cover portion 69A from the bulging window portion 69B of the lubricant pocket 69. The lubricating oil 100 collected in the bulging cover portion 69A can be supplied to the thrust bearing 62 and the like of the thrust receiver 61 as shown in FIG. 11, and the thrust receiver 61 can be kept in a lubrication state.

  Further, at this time, the lubricating oil supplied so as to be ejected from the oil passage 29 </ b> A of the support pin 29, for example, adheres to the inner surface of the carrier 30 due to the rotation of the planetary gear 28 between the annular plate portions 30 </ b> A and 30 </ b> B of the carrier 30. The lubricating oil then flows downward in the direction of arrow E in FIG. 11 due to natural fall (self-weight) or the like. The lubricating oil guide 66 can keep the thrust receiver 61 in a lubricating state while collecting the lubricating oil in the lubricating oil pocket 69 via the through hole 67.

  When an axial thrust load F is applied to the rotating shaft 18 by the rotation of the electric motor 17, the end surface on the front end side of the rotating shaft 18 contacts the rotating body 65 (convex surface portion 65A) of the thrust receiver 61, The rotating body 65 smoothly rotates following the rotating shaft 18 so that the thrust load F at this time can be received on the convex surface portion 65A side, and the rotation of the rotating shaft 18 is made smooth (stabilized). be able to.

  As described above, even when the amount of the lubricating oil 100 accommodated in the traveling drive device 11 is set to a necessary minimum amount of oil (for example, about 1/5 to 1/3 of the internal volume), The thrust receiver 61 that receives the thrust load F from the rotating shaft 18 on the center side can be sufficiently supplied with the lubricating oil 100 through the lubricating oil guide 66, and the thrust bearing 62 and the like of the thrust receiver 61 are in a lubricated state. Can keep.

  As a result, the thrust load F from the rotating shaft 18 can be stably received by the thrust receiver 61, and even when the rotating shaft 18 is formed as a long shaft body, smooth rotation of the rotating shaft 18 can be compensated for, The durability and life of the device can be improved.

  Further, an annular seal body 63 is provided between the outer ring 62A and the inner ring 62C of the thrust bearing 62, and the thrust bearing 62 is configured as a bearing with a seal, so that the thrust bearing 62 is guided to the thrust bearing 62. The lubricating oil 100 can be held inside the bearing, the inside of the thrust bearing 62 can be kept in a lubricated state, and the occurrence of oil film breakage or the like can be prevented.

  Further, in the present embodiment, the axle housing 12 provided on the rear wheel 7 side of the vehicle is provided with a motor housing cylinder 14 and a cylindrical spindle 15 that is detachably provided on the outside of the motor housing cylinder 14 in the axial direction. The lubricating oil 100 in the oil reservoirs 57 and 58 is removed from the annular space C between the wheel mounting cylinder 19 and the cylindrical spindle 15 at the lower part on the outer peripheral side of the cylindrical spindle 15. A lubricating oil discharge portion 78 that sucks outside and discharges in the direction of arrow G is provided.

  The lubricating oil discharge portion 78 is more than the cylindrical spindle 15 with respect to the retainer 71 of the seal device 70 that seals the lubricating oil 100 in the annular space C between the cylindrical spindle 15 and the wheel mounting cylinder 19. It is configured by connecting the suction port 79A of the discharge pipe 79 at a lower position, and this discharge pipe 79 is configured to discharge the lubricating oil 100 in the annular space C from the suction port 79A to the outside of the retainer 71. .

  Therefore, when the lubricating oil 100 in the oil reservoirs 57 and 58 is sucked and discharged from the suction port 79A of the discharge pipe 79 to the outside, the lubricating oil 100 is annular between the cylindrical spindle 15 and the wheel mounting cylinder 19. It is discharged to the outside through the space C, and it is possible to prevent the old lubricating oil 100 having a high oil temperature from staying in the annular space C, and the circulation (discharge) performance of the lubricating oil 100 in the annular space C Can be increased.

  The bearings 20 and 21 provided between the cylindrical spindle 15 and the wheel mounting cylinder 19 can be supplied with highly circulated lubricating oil 100 that circulates in the annular space C toward the suction port 79A of the discharge pipe 79. The bearings 20 and 21 can always be kept in a lubrication state with the new lubricating oil 100, and the lubricating oil 100 at this time is smoothly discharged to the outside of the wheel mounting cylinder 19 (annular space C) via the discharge pipe 79. be able to.

  Further, between the last stage carrier 39 and the cylindrical spindle 15, an oil groove 39A as an oil passage is provided at the lowest part of both, so that the lubricating oil 100 supplied from, for example, the lubricating oil supply passage 44 is provided. Can be smoothly circulated from the cylindrical spindle 15 into the wheel mounting cylinder 19 through the oil groove 39A, and the circulation performance of the lubricating oil 100 between the cylindrical spindle 15 and the wheel mounting cylinder 19 can be enhanced.

  In addition, since the carriers 30 and 39 of the planetary gear speed reduction mechanisms 25 and 34 are provided on the cylindrical spindle 15 in a non-rotating state, the rotation of the carriers 30 and 39 can be restricted by the cylindrical spindle 15. , 39 is not required to be specially managed, and load distribution of the plurality of support pins 29, 38 and the planetary gears 28, 37 assembled to the carriers 30, 39 can be easily performed. it can.

  The carriers 30 and 39 have sufficient rigidity to support the plurality of planetary gears 28 and 37 so as to be rotatable, and can be formed into a sturdy structure. It can be used as a strength member for the rotating portion (for example, the cylindrical spindle 15), and the strength and rigidity of the entire apparatus can be increased. Further, this can reduce the thickness of the cylindrical spindle 15 and reduce the weight.

  Therefore, according to the present embodiment, it is possible to improve workability and productivity in manufacturing the carriers 30, 39 and the like, and to improve workability when the planetary gear speed reduction mechanisms 25, 34 are assembled. Can do. Further, the new lubricating oil 100 can be continuously supplied to the ring gears 27 and 36 of the planetary gear speed reduction mechanisms 25 and 34, the thrust receiver 61 and the like, and the durability of the bearings 20 and 21 and the ring gears 27 and 36 and the thrust receiver 61 and the like can be maintained. And the life can be improved.

  Further, by reducing the amount of the lubricating oil 100 accommodated in the cylindrical spindle 15 and the wheel mounting cylinder 19 to the necessary minimum liquid level, the stirring resistance in the apparatus can be reduced and heat generation can be suppressed. At the same time, the rotational load of the apparatus can be reduced.

  Further, since the first stage planetary gear speed reduction mechanism 25 is accommodated inside the cylindrical spindle 15, the dimension of the second stage planetary gear speed reduction mechanism 34 projecting outward from the cylindrical spindle 15 in the axial direction is set. The axial length (full length) of the entire travel drive device 11 can be shortened, and the entire device can be reduced in size and weight.

  In addition, since the carriers 30 and 39 of the planetary gear speed reduction mechanisms 25 and 34 are provided on the cylindrical spindle 15 in a non-rotating state, the support pins 29 and 38 that rotatably support the planetary gears 28 and 37 are provided on the carrier 30. , 39 can be maintained in a non-rotating state, and the conduits 45, 50 of the lubricating oil supply passages 44, 47 can be stably connected to the oil passages 29A, 38A in the support pins 29, 38. .

  Such support pins 29, 38 are arranged at regular intervals around the sun gears 26, 35 and form the center of rotation of the planetary gears 28, 37. The lubricating oil supplied into the 38 oil passages 29A, 38A can be injected radially by the action of centrifugal force accompanying the rotation of the planetary gears 28, 37. For example, the planetary gears 28, 37 and the sun gears 26, 35 can be injected. The lubricating oil refined in the form of a mist can be supplied almost evenly to the meshing surfaces of the gears, the meshing surfaces of the planetary gears 28 and 37 and the ring gears 27 and 36, and the like.

  Thereby, the lubricating oil can be efficiently supplied to the speed reduction mechanism 24, and the durability and life of each component (gear) of the speed reduction mechanism 24 can be improved. The lubricating oil supplied to the meshing surfaces of the gears is stored in the oil reservoirs 57 and 58 by natural fall, and can lubricate, for example, the internal teeth 27A and 36A of the ring gears 27 and 36, and the rotating wheels. The bearings 20, 21 and the like can be kept in a lubrication state between the mounting cylinder 19 and the non-rotating cylindrical spindle 15.

  Further, an oil passage 30E is formed in the carrier 30 provided in a non-rotating state in the cylindrical spindle 15 at a position spaced apart from each planetary gear 28 in the circumferential direction as shown by a dotted line in FIG. The branch pipe 49 of the passage 47 and the conduit 50 can be communicated with each other by the oil passage 30E before and after the carrier 30, and the oil passage 30E of the carrier 30 can be used as a lubricating oil supply passage.

  Next, FIG. 13 shows a second embodiment of the present invention. The feature of the present embodiment is that the thrust receiver is provided in a stepped manner provided rotatably on the center side of the carrier via a cylindrical bush. This is because it is constituted by a disk-shaped rotating body. In the present embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and the description thereof is omitted.

  In the figure, reference numeral 91 denotes a thrust receiver that receives a thrust load F from the rotary shaft 18, and the thrust receiver 91 is configured in substantially the same manner as the thrust receiver 61 described in the first embodiment. However, the thrust receiver 91 in this case is different in that it is constituted by a bush 92 and a rotating body 93 which will be described later.

  Reference numeral 92 denotes a bush attached to the inner peripheral side of the annular plate portion 30B via a bearing attachment portion 32. The bush 92 is formed as a cylindrical ring from a hard material having high wear resistance. Is fitted (fixed) into the annular bearing mounting portion 32. The bush 92 is disposed coaxially with the rotary shaft 18 and the axial displacement in the bearing mounting portion 32 is restricted by the stopper 64 described in the first embodiment.

  Reference numeral 93 denotes a stepped disk-like rotating body that is rotatably provided in the bearing mounting portion 32 of the carrier 30 via a bush 92. The rotating body 93 is the rotating body 65 described in the first embodiment. And has a convex surface portion 93 </ b> A that comes into contact with the end surface on the front end side of the rotating shaft 18. However, oil passages 94 and 95, which will be described later, are formed in the rotating body 93 in this case.

  94 is an oil passage for lubricating oil drilled on the center side of the rotator 93. The oil passage 94 penetrates the rotator 93 in the axial direction and opens at the end face of the convex portion 93A. The oil passage 94 supplies lubricating oil 100 guided from a lubricating oil guide 96 described later to the contact surface with the rotary shaft 18.

  95 are other oil passages drilled in the radial direction of the rotary body 93. These oil passages 95 extend in the radial direction of the rotary body 93 in a cross shape as a whole, for example, and an oil passage 94 is formed. And always in communication. The oil passage 95 supplies the lubricating oil 100 to the sliding contact surface with the bush 92 and keeps the sliding contact surface between the bush 92 and the rotating body 93 in a lubricated state.

  A lubricating oil guide 96 is provided on the annular plate portion 30B of the carrier 30. The lubricating oil guide 96 is substantially the same as the lubricating oil guide 66 described in the first embodiment, and has a through hole 67 and a lubricating oil pocket. 98. The lubricating oil pocket 98 of the lubricating oil guide 96 is configured in the same manner as the lubricating oil pocket 69 described in the first embodiment, and includes a lower bulging cover portion 98A, an upper bulging window portion 98B, and a communication hole. It has a portion 98C.

  However, the lubricating oil pocket 98 in this case has a configuration in which the punching hole 69D (see FIG. 11) is eliminated, and the bulging cover portion 98A completely covers the rotating body 93 and the like of the thrust receiver 91 from the outside in the axial direction. ing. For this reason, the lubricating oil 100 is accommodated in the bulging cover portion 98A of the lubricating oil pocket 98 up to a height position corresponding to the oil passage 94, for example.

  Thus, also in the present embodiment configured as described above, the thrust load F from the rotating shaft 18 is smoothed by the bush 92 and the rotating body 93 by bringing the rotating body 93 into contact with the end surface of the rotating shaft 18. And substantially the same operational effects as those of the first embodiment can be obtained.

  In particular, in the present embodiment, the thrust receiver 91 can be configured with a simple structure by the rotating body 93 that is rotatably provided on the center side of the carrier 30 via the bush 92. The lubricating oil 100 guided from the lubricating oil guide 96 can be supplied to the contact surface with the rotating shaft 18 by the oil passages 94, 95 provided in the rotating body 93, and the sliding contact between the bush 92 and the rotating body 93 is possible. Lubricating oil 100 can also be supplied to the surface, and the abutting surface and sliding surface can be kept in a lubrication state to prevent the occurrence of oil film breakage or the like.

  In the above-described embodiment, the case where the first stage carrier 30 is fixed to the annular convex portion 15A of the cylindrical spindle 15 with the bolt 31 has been described as an example. However, the present invention is not limited to this. For example, the first stage carrier may be integrally formed in the cylindrical spindle 15 using means such as casting or forging. It is sufficient that the configuration is provided in a non-rotating state.

  In the above-described embodiment, the case where the second stage carrier 39 is fixed to the flange portion 15 </ b> C of the cylindrical spindle 15 using the bolt 40 has been described as an example. However, the present invention is not limited to this. For example, the final stage carrier may be integrally formed on the opening end side of the cylindrical spindle 15 using means such as casting or forging.

  In the above-described embodiment, the case where the speed reduction mechanism 24 is configured by the first-stage and second-stage planetary gear speed reduction mechanisms 25 and 34 has been described as an example. However, the present invention is not limited to this. For example, the speed reduction mechanism may be configured by a planetary gear speed reduction mechanism having three or more stages.

  In the above embodiment, the case where the electric motor 17 is used as a drive source has been described as an example. However, the present invention is not limited to this. For example, a hydraulic motor or the like may be used as a drive source of the travel drive device.

  Further, in the above embodiment, the rear wheel drive type dump truck 1 has been described as an example. However, the present invention is not limited to this. For example, the present invention may be applied to a front-wheel drive type or a four-wheel drive type dump truck that drives both front and rear wheels.

It is a front view which shows the dump truck by embodiment of this invention. It is a block diagram which shows the traveling drive apparatus of a dump truck. FIG. 3 is a cross-sectional view of the traveling drive device on the rear wheel side as viewed from the direction of arrows III-III in FIG. 1 with the wheel cap removed. It is sectional drawing which expands and shows the motor accommodation cylinder, cylindrical spindle, wheel attachment cylinder, planetary gear reduction mechanism, etc. in FIG. It is a left view of FIG. 4 which expands and shows a disc brake etc. It is sectional drawing which expands and shows the wheel attachment cylinder in FIG. 4, a planetary gear reduction mechanism, etc. It is sectional drawing which expands further and shows the planetary gear reduction mechanism etc. in FIG. FIG. 8 is an assembled state diagram in which the carrier of the planetary gear reduction mechanism, the planetary gear, and the like are enlarged from the direction of arrows VIII-VIII in FIG. 7. FIG. 9 is a perspective view of the carrier, the lubricant guide, each planetary gear, and the like in FIG. 8 as viewed obliquely from above. FIG. 10 is an enlarged perspective view of a carrier, a lubricant guide, a thrust receiver, and the like that are broken from an arrow XX direction in FIG. 9. It is sectional drawing which expands and shows the carrier, lubricating oil guide, thrust receiver, rotating shaft, etc. in FIG. It is sectional drawing which expands and shows the sealing apparatus etc. which were provided between the cylindrical spindle in FIG. 6, and a wheel attachment cylinder. It is sectional drawing in the same position as FIG. 11 which shows the lubricating oil guide and thrust receiver by 2nd Embodiment with a carrier etc.

Explanation of symbols

1 Dump truck 2 Car body 3 Vessel 5 Cabin 6 Front wheel 7 Rear wheel (wheel)
8 Engine 9 Alternator (generator)
DESCRIPTION OF SYMBOLS 10 Electric controller 11 Travel drive device 12 Axle housing 13 Suspension cylinder 14 Motor accommodating cylinder 15 Cylindrical spindle 17 Electric motor (drive source)
18 Rotating shaft 19 Wheel mounting cylinder 20, 21 Bearing 22 Disk holding cylinder 23 Disk 24 Reduction mechanism 25, 34 Planetary gear reduction mechanism 26, 35 Sun gear 27, 36 Ring gear 28, 37 Planetary gear 29, 38 Support pin 30, 39 Carrier 33 Coupling 44, 47 Lubricating oil supply path (lubricating oil supply means)
56 Disc brake 57, 58 Oil reservoir 61, 91 Thrust receiver 62 Thrust bearing 63 Seal body 65, 93 Rotating body 66, 96 Lubricating oil guide 67 Through hole 69, 98 Lubricating oil pocket 70, 81 Sealing device 78 Lubricating oil discharge part ( Lubricating oil discharge means)
79 discharge pipe 82 wedge member 83 undulation cylinder 100 lubricating oil

Claims (5)

A cylindrical axle housing that is attached to the body of the dump truck in a non-rotating state, a rotating shaft that extends in the axial direction inside the axle housing and is driven to rotate by a drive source, and a bearing on the outer peripheral side of the axle housing A wheel mounting cylinder that is rotatably provided via a wheel, and a planetary gear reduction that is provided between the wheel mounting cylinder and the axle housing and transmits the rotation of the rotating shaft to the wheel mounting cylinder at a reduced speed. In the traveling drive device of the dump truck comprising the mechanism,
The planetary gear reduction mechanism has a non-rotating carrier that rotatably supports a plurality of planetary gears and is provided in the axle housing in a non-rotating state,
The carrier is provided with a thrust receiver that comes into contact with the end surface of the rotating shaft and receives a thrust load from the rotating shaft, and a lubricating oil guide that guides the lubricating oil supplied from the outside to the thrust receiver ,
The thrust receiver is provided on the center side of the carrier and is capable of receiving a thrust load from the rotating shaft, and is rotatably supported by the thrust bearing and abuts against the end surface of the rotating shaft. A travel drive device for a dump truck, characterized by comprising a disk-like rotating body that rotates following a rotating shaft .   The lubricating oil guide is positioned between the through hole formed in the carrier at a position that is above and below the thrust receiver, and between the through hole and the thrust receiver. The travel drive device for a dump truck according to claim 1, comprising a lubricant pocket that is formed and collects the lubricant through a through hole. 3. The dump truck travel drive device according to claim 1, wherein the thrust bearing is configured by a bearing with a seal that holds therein the lubricating oil guided from the lubricating oil guide. 4. A cylindrical axle housing that is attached to the body of the dump truck in a non-rotating state, a rotating shaft that extends in the axial direction inside the axle housing and is driven to rotate by a drive source, and a bearing on the outer peripheral side of the axle housing A wheel mounting cylinder that is rotatably provided via a wheel, and a planetary gear reduction that is provided between the wheel mounting cylinder and the axle housing and transmits the rotation of the rotating shaft to the wheel mounting cylinder at a reduced speed. In the traveling drive device of the dump truck comprising the mechanism,
The planetary gear reduction mechanism has a non-rotating carrier that rotatably supports a plurality of planetary gears and is provided in the axle housing in a non-rotating state,
The carrier is provided with a thrust receiver that comes into contact with the end surface of the rotating shaft and receives a thrust load from the rotating shaft, and a lubricating oil guide that guides the lubricating oil supplied from the outside to the thrust receiver,
The thrust receiver is a cylindrical bush fixed to the carrier so as to be coaxial with the rotation shaft, and is rotatably fitted on the inner peripheral side of the bush. It is constituted by a disk-shaped rotating body that rotates following the rotation axis by abutting ,
The rotating body is formed with an oil passage for lubricating oil for supplying the lubricating oil guided from the lubricating oil guide to a contact surface with the rotating shaft and a sliding contact surface with the bush. travel drive apparatus of the dump truck to be. The lubricating oil guide is positioned between the through hole formed in the carrier at a position that is above and below the thrust receiver, and between the through hole and the thrust receiver. The travel drive device for a dump truck according to claim 4, which is formed by a lubricant pocket that is formed and collects the lubricant through a through hole.

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