JP4477527B2 - 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 at, for example, an open-pit mine, a quarry, a mine, and the like, and particularly when traveling using a speed reduction mechanism. The present invention relates to a traveling drive device for a dump truck configured to increase the rotational torque of the dump truck.

  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 a drive wheel of a dump truck includes a cylindrical axle housing that is attached to a vehicle body, a drive source such as a hydraulic motor that is provided in the axle housing and rotationally drives a rotating shaft, and the axle A wheel mounting cylinder provided rotatably on a front end side outer periphery of the housing through which a wheel is mounted, and provided between the wheel mounting cylinder and the rotation shaft, the rotation shaft being rotated with respect to the wheel mounting cylinder. A plurality of planetary gear speed reduction mechanisms that transmit by decelerating (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 dump truck according to the prior art described above has a vehicle weight of 190 t or more, and the traveling drive device has a weight of 10 t or more, a total length of 3 m or more, and an outer diameter dimension even when a tire of a driving wheel is removed, for example. Reaches 1.5m or more. The axle housing, which is a main component of the travel drive device, is generally formed as a heavy and long cylindrical member (for example, a total length of about 2 m and a weight of about 2 t) from an integrally formed product by casting.

  For this reason, in the prior art, a great deal of labor and time are spent on obtaining materials, machining, inspection after processing, and the like when manufacturing the axle housing. Moreover, in a dump truck assembly factory, there is a problem in that handling of heavy axle housings is troublesome and workability during assembly cannot be improved.

  In addition, for service work and maintenance work after the manufacture and shipment of dump trucks, replacement of consumables such as seals used for travel drive devices, adjustment of bearing preload (set load), sampling of lubricating oil (oil Exchange) etc. are mainly needed. However, the conventional dump truck traveling drive apparatus has the following problems.

  In other words, when the axle housing is formed as a long cylindrical member, consumables such as seals can be replaced unless the components such as the wheel mounting cylinder and the speed reduction mechanism are removed from the axle housing and disassembled. There is a problem in that maintenance work for exchanging seals and the like takes time and labor burdens are increased.

  Also, in the preload adjustment work of the bearing, unless the respective components such as the wheel mounting cylinder and the speed reduction mechanism are once removed from the axle housing and disassembled, for example, the bearing preload adjustment provided between the axle housing and the wheel mounting cylinder is adjusted. It is difficult to carry out properly, and in this case, there is a problem that workability during maintenance is poor.

  In particular, the driving device for a dump truck is a large-sized component such as a wheel mounting cylinder or a speed reduction mechanism, and a long axle housing is used. Often done. Then, the mounting and dismounting operations of each component in the state where the axle housing is placed vertically is a high-place operation performed at a height of, for example, 2 m or more.

  For this reason, in the prior art, it is necessary to assemble a strong scaffold in preparation for assembly work at a high place, and there is a problem that the burden on the worker increases. In addition, when installing a lubricating oil pipe, a brake pipe, etc. in the axle housing, an operation for turning the axle housing up and down is required, which further increases the burden on the operator.

  For example, when performing maintenance work on a dump truck at a site such as a mining site, it is necessary to have special equipment such as scaffolding, cranes for suspending heavy loads, reversing machines, etc. There is a problem of spending a lot of labor and time.

  The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to divide the axle housing into a plurality of members, thereby reducing, for example, work at a high place where a scaffold is assembled. An object of the present invention is to provide a traveling drive device for a dump truck that can improve workability at the time.

  Another object of the present invention is to efficiently perform seal replacement, bearing preload adjustment, etc. during maintenance at the work site, for example, and to reduce the burden on the operator and improve workability during maintenance. It is an object of the present invention to provide a travel drive device for a dump truck that can be increased.

  In order to solve the above-described problems, the present invention provides a cylindrical axle housing that is attached to the body of a dump truck in a non-rotating state, a drive source that is provided in the axle housing and rotationally drives a rotating shaft, and the axle housing A wheel mounting cylinder rotatably provided via a bearing on the outer peripheral side of the wheel, and provided between the wheel mounting cylinder and the axle housing, the rotation of the rotating shaft is decelerated relative to the wheel mounting cylinder. The present invention is applied to a travel drive device for a dump truck comprising a speed reduction mechanism that transmits the information.

A feature of the configuration adopted by the invention of claim 1 is that the axle housing is disposed inside the cylindrical drive source accommodating portion for accommodating the drive source therein and radially inward of the wheel mounting cylinder. A cylindrical spindle that rotatably supports the wheel mounting cylinder via the cylindrical spindle, and the cylindrical spindle is configured to be detachably connected to the drive source accommodating portion at an axial end portion ; A preliminary assembly is configured by pre-assembling the wheel mounting cylinder and the speed reduction mechanism on the cylindrical spindle, and the cylindrical spindle is connected to the drive source accommodating portion in a state of the preliminary assembly. Sealing means for sealing the space between the wheel mounting cylinder and the cylindrical spindle and allowing the wheel mounting cylinder to rotate around the cylindrical spindle is provided at a connecting position between the cylindrical spindle and the drive source accommodating portion. Establishment The sealing means is to have a configuration that exposes the tubular spindle to the outside from the tubular spindle when removed from the drive source housing unit in the state of the preliminary assembly.

According to the invention of claim 2 , the set load of the bearing disposed between the wheel mounting cylinder and the cylindrical spindle is adjusted in the vicinity of the connection position between the cylindrical spindle and the drive source accommodating portion. It is set as the structure which provides a set load adjustment part.

Further, according to the invention of claim 3 , attachment and removal of the bearing with respect to the cylindrical spindle are performed from an end side closer to a connection position with the drive source accommodating portion on both axial sides of the cylindrical spindle. It is configured to do.

As described above, according to the first aspect of the present invention, the cylindrical axle housing is supported in such a manner that the cylindrical drive source accommodating portion for accommodating the drive source therein and the wheel mounting cylinder are rotatably supported via the bearings. The cylindrical spindle is formed so as to be detachably connected to the drive source housing portion at the end in the axial direction so that the heavy and long axle housing can be connected to the drive source. It can be formed as a separate member of the housing portion and the cylindrical spindle, and each can be made small and lightweight to improve handling properties. For this reason, the high place work etc. which built the scaffold like the prior art can be reduced significantly, and the workability | operativity at the time of an assembly can be improved.

Further, constitute a subassembly in advance assembled wheel mounting and reduction mechanism or the like to the tubular spindle, since the tubular spindle is configured to be coupled to the drive source housing unit in the state of the preliminary assembly, the wheels The pre-assembly work for assembling the mounting cylinder, the speed reduction mechanism, and the like to the cylindrical spindle can be easily performed without assembling a special scaffold or the like, and the burden on the operator can be greatly reduced. Then, the axle housing can be assembled by connecting the cylindrical spindle to the drive source accommodating portion in the state of the preliminary assembly, so that the entire apparatus can be efficiently assembled.

Moreover, the sealing means provided at the coupling position between the cylindrical spindle and the drive source housing unit, said sealing means, said cylinder and said tubular spindle when removed from the drive source housing unit in the state of the preliminary assembly since a structure exposed to the outside from Jo spindle, for example, even if the work site mine like performing maintenance work of the seal replacement, only remove the tubular spindle from the drive source housing unit, facilitates the sealing means Can be maintained and inspected. For this reason, it is not necessary to disassemble a preliminary assembly composed of a cylindrical spindle, a wheel mounting cylinder, a speed reduction mechanism, and the like for seal replacement, and the workability during maintenance can be greatly improved. The sealing means can reliably seal the space between the rotating wheel mounting cylinder and the non-rotating cylindrical spindle, preventing leakage of internal lubricating oil, and intrusion of external rainwater and the like. Can also prevent.

On the other hand, since the invention according to claim 2 is configured such that the set load adjusting portion is provided in the vicinity of the connecting position between the cylindrical spindle and the drive source accommodating portion, the drive source accommodating portion is removed from the cylindrical spindle in this case as well. This makes it easy to adjust the set load on the bearing, and it is necessary to disassemble the preliminary assembly consisting of the cylindrical spindle, wheel mounting cylinder, speed reduction mechanism, etc. to adjust the set load of the bearing. Therefore, workability during maintenance can be greatly improved.

According to a third aspect of the present invention, the mounting and removal of the bearing with respect to the cylindrical spindle are carried out from one end of the cylindrical spindle on both sides in the axial direction that is close to the connection position with the drive source accommodating portion. Since it is configured, for example, a reaction force receiving portion that receives the reaction force of the speed reduction mechanism can be provided at the other end portion of the cylindrical spindle that is located on the opposite side of the connection position. The outer diameter can be larger than the inner diameter. This eliminates the need for a separate reaction force receiving part separate from the cylindrical spindle, reduces the number of parts and improves workability during assembly, and provides sufficient strength from the reaction force from the speed reduction mechanism. Can be accepted. When performing a bearing installation operation or a bearing replacement operation on the outer peripheral side of the cylindrical spindle, the bearing is installed and removed from the end of the one side with the speed reduction mechanism assembled to the cylindrical spindle. Work can be easily performed, and workability during assembly and maintenance can be improved.

  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.

  Reference numerals 7 and 7 denote left and right rear wheels rotatably provided on the rear side of the vehicle body 2. The rear wheels 7 constitute drive wheels of the dump truck 1, and will be described later with reference to FIG. 11 is driven to rotate 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. 3) provided in combination.

  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 62 and a steering cylinder (not shown) for power steering. 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 formed as a cylindrical body having a tapered shape as shown in FIGS. In the interior, an electric motor 17 (to be described later) serving as a drive source for the rear wheel 7 is accommodated. The motor housing cylinder 14 has a large diameter portion 14A on one side in the axial direction, and the large diameter portion 14A side is detachably fixed to the suspension cylinder 13 shown in FIG. 2 using bolts or the like.

  The other side in the axial direction of the motor housing cylinder 14 is a small-diameter portion 14B. On the small-diameter portion 14B side, a connecting portion 15B of a cylindrical spindle 15 described later is provided with a plurality of bolts 16 (as shown in FIGS. 5 and 7). And the like (see FIG. 14). That is, the axle housing 12 is divided between the motor housing cylinder 14 and the cylindrical spindle 15 as shown in FIG. 12, and the small diameter portion 14B of the motor housing cylinder 14 and the connecting portion 15B of the cylindrical spindle 15 are It constitutes a connection position.

  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. 5 and 7, it is formed as a first reduction gear housing space A to be described later. 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. 7 and 8, an annular flange portion 15 </ b> C protruding outward in the radial direction is integrally formed.

  The flange portion 15C of the cylindrical spindle 15 constitutes a large-diameter reaction force receiving portion to which a final stage carrier 39, which will be described later, is fixedly attached. Thus, the cylindrical spindle 15 is assembled as a covered cylindrical body having a sturdy structure by fixing the carriers 30 and 39 of the planetary gear speed reduction mechanisms 25 and 34, which will be described later, on the outer peripheral side thereof. The wheel mounting cylinder 19 (rear wheel 7) can be supported from the inside with high rigidity (strength). The cylindrical spindle 15 also has a function of receiving a rotational reaction force generated in a later-described reduction mechanism 24 (planetary gear reduction mechanisms 25 and 34) with sufficient strength through the carriers 30 and 39. Yes.

  Further, the first reduction gear housing space A described above is surrounded by a motor housing cylinder 14 and a cylindrical spindle 15 as shown in FIGS. 5 and 7, and one side (inside) in the axial direction thereof is an electric motor 17 described later. The other side (outside) in the axial direction is closed and covered with a coupling 33 and the like which will be 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.

  The electric motor 17 has a rotary shaft 18 extending in the axial direction from the motor housing cylinder 14 toward the reduction gear housing space A in the cylindrical spindle 15 as shown in FIGS. 4 and 5. 18 is rotationally driven by the electric motor 17 in the forward or reverse direction.

  Here, the rotating shaft 18 is detachably connected at one side (base end side) in the axial direction to the rotor side (not shown) of the electric motor 17 using means such as a spline, for example, FIGS. In the middle stage of the assembly shown in FIG. 6 and the like, the rotary shaft 18 is separated from the electric motor 17 (see FIG. 7). Further, the sun gear 26 (described later) is spline-coupled to the other axial side (front end side) of the rotary shaft 18 so as to rotate integrally.

  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. The wheel mounting cylinder 19 includes a one-side cylinder portion 19A extending in the axial direction between the bearings 20 and 21, and an end surface of the one-side cylinder portion 19A extending in the axial direction toward a ring gear 36 to be described later. 19B1 is formed as a stepped cylindrical body by the other side cylinder part 19B formed with an inner diameter larger than the one side cylinder part 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 cylindrical portion 19A, the retainer 54 of the seal device 51 described later is attached, which is located between the end surface on the one side in the axial direction and the bearing attachment portion 19C and expands in a tapered shape. A retainer mounting portion 19E as an expanding portion is formed.

  Further, the other cylinder portion 19B of the wheel mounting cylinder 19 has an inner peripheral surface 19B1 having an inner diameter 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 a radial direction outer side, and permits the lubricating oil 100 to distribute | circulate from the reduction gear accommodation space B mentioned later toward the annular space C. It is.

  A ring gear 36 (discussed below) and a disk holding cylinder 22 for the disk 22A are integrally fixed to the other side cylinder portion 19B of the wheel mounting cylinder 19 using a long bolt 23 (see FIG. 6), etc. The mounting cylinder 19 is rotated integrally with the ring gear 36. In this case, 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 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.

  Here, 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 reduction gear housing space B in which a second stage planetary gear speed reduction mechanism 34 described later is housed. 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 60, and the like, which will be described later.

Further, between the wheel mounting case 19 and the cylindrical spindle 15, tubular spindle 15 To囲no ring-shaped space C next to the annular outer peripheral side of the lower portion of the annular space C is below the lubricating oil 100 Is to be 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, the one side cylinder portion 19A of the wheel mounting cylinder 19 has an inner circumferential 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, and the lubricating oil 100 in the annular space C is guided toward the later-described discharge pipe 59 by the inclined surface 19F. . On the side of the retainer mounting portion 19E of the wheel mounting cylinder 19, a seal device 51, which will be 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. Yes.

  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 using, for example, the same tapered roller bearing or the like. Between the one side cylinder portion 19 </ b> A and the cylindrical spindle 15, it is disposed so as to be separated in the axial direction. 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.

  When the bearings 20 and 21 are fitted and attached to the outer peripheral side of the cylindrical spindle 15, the bearings 20 and 21 attached in advance to the bearing attachment portions 19C and 19D of the wheel attachment cylinder 19 as shown in FIG. The cylindrical spindle 15 is attached by being inserted into the outer peripheral side from the connecting portion 15B side.

  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 sandwiches the ring gear 36 at a position on the outer side in the axial direction of the wheel mounting cylinder 19 as shown in FIG. It attaches and is detachably fixed (integrated) to the wheel mounting cylinder 19 using a plurality of long bolts 23, 23,... Shown in FIG.

  As shown in FIG. 6, a ring-shaped (annular) disk 22 </ b> A is secured to the disk holding cylinder 22 and is attached in a rotating state. The disk 22 </ b> A is given a braking force by a disk brake 46 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 22A, and the rotation during running is stopped (braking) by the braking force applied to the disk 22A.

  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 reduction mechanism which is a carrier fixed type and is provided in the cylindrical spindle 15 of the axle housing 12. The planetary gear reduction mechanism 25 is shown in FIGS. 4, 5, 7 and 8. As shown, for example, three planetary gears that mesh with the sun gear 26 splined to the tip end of the rotating shaft 18 and the sun gear 26 and the internal teeth 27A of the ring gear 27 and rotate according to the rotation of the sun gear 26. 28 (see FIG. 13) and a carrier 30 which rotatably supports each planetary gear 28 via a support pin 29.

  The first stage carrier 30 is fixed to the annular convex portion 15A of the cylindrical spindle 15 in a non-rotating state and detachably using a plurality of bolts 31 (see FIGS. 8 and 13). A plurality of planetary gears 28 and the like are housed in a reduction gear housing space A of the cylindrical spindle 15. Further, on the inner peripheral side of the carrier 30, as shown in FIG. 8, a bearing 32 that rotatably supports the tip end side of the rotating shaft 18 is provided.

  The first stage ring gear 27 is formed as a short cylindrical gear that surrounds the sun gear 26, the planetary gear 28, the support pin 29, the carrier 30, and the like from the outside in the radial direction, and is formed on the inner peripheral side of the cylindrical spindle 15. It arrange | positions so that relative rotation is possible via a small radial gap (for example, about 2-5 mm). Then, on the inner peripheral side of the ring gear 27, internal teeth 27A (see FIG. 8) that mesh with the planetary gears 28 are formed.

  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 the carrier 30 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 FIG. 8, a lubricating oil passage 29A is formed in the support pin 29 of each planetary gear 28, and a lubricating oil conduit extending in the axial direction in the cylindrical spindle 15 is formed in the oil passage 29A. (Not shown) is connected. The lubricating oil introduced into the oil passage 29A from this conduit is supplied so as to be injected toward the bearings 28A and the like of the planetary gear 28, and the tooth surfaces of the bearings 28A and the planetary gear 28 are kept in a lubricated state. Is.

  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 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. 8) 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 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. 8) or the like. 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. 8, 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 so as to be rotatable from both sides in the axial direction with the coupling 33. 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. And are integrally fixed to each other. Further, on the inner peripheral side of the ring gear 36, internal teeth 36A (see FIG. 8) 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. 8, an oil passage 38A for lubricating oil is formed in the support pin 38 of each planetary gear 37, and a conduit 48 described later is connected to the oil passage 38A from the outside of the carrier 39. The lubricating oil introduced into the oil passage 38A from the conduit 48 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 kept in a lubrication state. Is.

  In this case, as described above, the lubricating oil supplied to the planetary gear speed reduction mechanisms 25 and 34 naturally falls to the lower portions of the first and second reduction gear housing spaces A and B and the annular space C, for example, FIG. The lubricating oil 100 is accumulated in the cylindrical spindle 15 and the wheel mounting cylinder 19 with the liquid level shown in FIG.

  Further, 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 to the position used as the lower side of the wheel attachment cylinder 19 via.

  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 or the like in the second reduction gear housing space B from leaking from the inside of the carrier 39. .

  43 is a brake pipe arranged in the cylindrical sun gear 35 so as to extend in the axial direction. The brake pipe 43 is attached to the inner cap 42 at the front end side and is drawn out from the inner cap 42 to the outside. Further, the base end side (one side) of the brake pipe 43 extends toward the first-stage carrier 30 through an axial liquid hole (not shown) formed in the first-stage carrier 30. The other brake pipe 44 is connected.

  Further, as shown in FIG. 5, the other brake pipe 44 extends in the axial direction in the reduction gear housing space A of the cylindrical spindle 15, and the base end side thereof includes a brake hydraulic pressure control valve mounted on the vehicle. Via a master cylinder (not shown). When the brake is operated, the brake fluid pressure from the master cinder is supplied from the brake pipe 44 toward the brake pipe 43.

  Further, the distal end side of the brake pipe 43 drawn out from the inner cap 42 is connected to a total of three branch pipes 45, 45,... (See FIG. 6) made of, for example, a flexible hose. These branch pipes 45 supply the brake fluid pressure from the brake pipe 43 side to each disk brake 46 described later.

  46, 46,... Are a plurality of disc brakes that constitute a brake means together with the disc 22A. Each disc brake 46 is externally (decelerated) in the axial direction to the second stage carrier 39 as shown in FIG. It is attached using bolts 47 etc. from the outside of the machine housing space A). Further, a total of three disc brakes 46 are provided at intervals in the circumferential direction of the disc 22A as shown in FIG.

  The disc brake 46 is supplied with the brake fluid pressure from the master cylinder via the brake pipes 44, 43 and the branch pipes 45, so that the disc 22A is clamped from both sides in the axial direction, A braking force is applied to the wheel mounting cylinder 19 (rear wheel 7) that rotates integrally.

  48 are lubricating oil conduits, and these conduits 48 are connected to the oil passages 38A (see FIG. 8) of the respective support pins 38 at positions outside the carrier 39 as shown in FIG. . These conduits 48 are connected to lubricating oil supply pipes (not shown) arranged in the sun gear 35, the carrier 30, the cylindrical spindle 15 and the like in substantially the same manner as the brake pipes 43 and 44 shown in FIG. Has been. The lubricating oil from the supply pipe is supplied in an injected state into the oil passages 38A of the support pins 38 via the conduits 48.

  Reference numeral 49 denotes a drain hole formed in the lowermost portion of the wheel mounting cylinder 19, and the drain hole 49 extends in the axial direction through the ring gear 36 and the disk holding cylinder 22 as shown in FIG. The plug 50 is detachably closed. When the plug 50 is removed, the lubricating oil 100 accumulated in the wheel mounting cylinder 19 can be discharged to the outside through the drain hole 49.

  51 is a sealing device as a sealing means for sealing the space between the cylindrical spindle 15 and the wheel mounting cylinder 19, and the sealing device 51 is a so-called floating seal as shown in FIGS. It is configured. The sealing device 51 suppresses leakage of the lubricating oil 100 accommodated in the annular space C between the cylindrical spindle 15 and the wheel mounting cylinder 19 to the outside of the retainer 52 described later, and earth and sand, rainwater, etc. Intrusion into the annular space C is prevented.

  Here, as shown in FIG. 9, the sealing device 51 includes a fixed-side retainer 52 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 54 on the rotation side, which is located in the retainer mounting portion 19E of 19 and is attached to an end surface on one axial side via a bolt 53 or the like, and a pair of O-rings 55, 55 between these retainers 52, 54 And a pair of seal rings 56 and 56 disposed to face each other in the axial direction.

  The sealing device 51 elastically deforms the pair of O-rings 55 between the retainers 52 and 54 and the seal rings 56 and 56 to seal between the retainers 52 and 54 and the O-rings 55, and An axial pressing force is applied to each seal ring 56 with an elastic restoring force 55. As a result, the pair of seal rings 56 and 56 come in sliding contact with each other in the axial direction, and seal both sliding surfaces in a liquid-tight manner.

  Further, as shown in FIG. 9, the fixed-side retainer 52 has a cylindrical portion 52A fitted to the outer peripheral side of the cylindrical spindle 15, and projects radially inward from the base end side of the cylindrical portion 52A to receive the motor housing cylinder. 14 and an annular protrusion 52B sandwiched between the cylindrical spindle 15 and the connecting portion 15B of the cylindrical spindle 15, and a flange that protrudes radially outward from the proximal end side of the cylindrical portion 52A and is integrally formed with a holding portion 52C of the O-ring 55. Part 52D.

  The annular protrusion 52B of the retainer 52 contacts the end surface of the connecting portion 15B via a shim plate 58 described later when the cylindrical portion 52A is fitted to the outer peripheral side of the cylindrical spindle 15 (connecting portion 15B). The bolt 57 is fixed to the connecting portion 15B of the cylindrical spindle 15. Further, the flange 52D of the retainer 52 is formed with a connection port 52E to which a later-described discharge pipe 59 is connected.

  Reference numeral 58 denotes a shim plate as a set load adjusting portion for adjusting the set load of the bearings 20 and 21. The shim plate 58 is formed as an annular flat plate extending along the connecting portion 15B (end surface) of the cylindrical spindle 15. Between the connecting portion 15B of the cylindrical spindle 15 and the retainer 52 on the fixed side using a bolt 57. The shim plate 58 variably adjusts the interval S (see FIG. 9) between the annular protrusion 52B of the retainer 52 and the end surface of the cylindrical spindle 15 in accordance with the thickness or number of the shim plates 58.

  In this case, the cylindrical portion 52A of the retainer 52 fitted to the outer peripheral side of the cylindrical spindle 15 is in contact with the inner ring of the bearing 20 at the distal end side, and an axial set load (thrust load) on the bearing 20 is applied to the shim plate. 58 is variably adjusted according to the thickness or number of sheets. Further, the other bearing 21 disposed between the cylindrical spindle 15 and the wheel mounting cylinder 19 is 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 58.

  59 is a discharge pipe provided connected to the flange portion 52D of the retainer 52. The discharge pipe 59 is disposed at the lowest position between the cylindrical spindle 15 and the wheel mounting cylinder 19. For example, the lubricating oil 100 supplied as described above into the first and second reduction gear housing spaces A and B and the annular space C is brought out of the annular space C by a lubricating oil pump (not shown) of the vehicle. It is made to discharge | emit while attracting | sucking.

  In this case, one end of the discharge pipe 59 is attached to the connection port 52 </ b> E of the retainer 52, and is drawn out of the axle housing 12 (the motor housing cylinder 14) through the retainer 52. Further, the other end portion on the downstream side of the discharge pipe 59 is attached to the large-diameter portion 14A side of the motor housing cylinder 14, and another pipe (not shown) from the suspension cylinder 13 side of the axle housing 12 shown in FIG. ) And the like, connected to the suction side of the lubricating oil pump, a cooling device (not shown), and the like.

  Reference numeral 60 denotes another sealing device disposed at a position on the outer side in the axial direction of the wheel mounting cylinder 19, and the sealing device 60 is configured as a so-called floating seal, and as shown in FIGS. Between the last stage (second stage) carrier 39, a fixed retainer 60A is provided. The sealing device 60 is also configured in substantially the same manner as the sealing device 51 shown in FIGS. 7 and 9 arranged 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 from leaking to the outside from between the disk holding cylinder 22 and the retainer 60A on the carrier 39 side, and prevents the entry of external earth and sand, rainwater, and the like.

  61 is a wedge member that detachably fixes the rear wheel 7 to the outer peripheral side of the wheel mounting cylinder 19, and the wedge member 61 is arranged from the outer side in the axial direction of the wheel mounting cylinder 19 as shown in FIGS. 4 and 5. 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, 10 or more wedge members 61 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 61. is there. 7 to 12 show a state in which the rear wheel 7 and the wedge member 61 are removed from the outer peripheral side of the wheel mounting cylinder 19.

  62 is a hoisting cylinder for hoisting the vessel 3 of the lift truck 1 shown in FIG. 1, and the hoisting cylinder 62 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 hoisting cylinder 62 expands and contracts in the upward and downward directions when pressure oil is supplied and discharged from the outside, and causes the vessel 3 to hoist (tilt) around the pin coupling portion 4 on the rear side.

  Reference numeral 63 denotes a hydraulic oil tank, and the hydraulic oil tank 63 is attached to the side surface of the vehicle body 2 and the like, as shown in FIG. The hydraulic oil stored in the hydraulic oil tank 63 is supplied to and discharged from the hoisting cylinder 62 and a 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 vehicle is decelerated at a ratio, and the rear wheel 7 which is a driving wheel of the vehicle is driven to drive 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.

  Next, an assembly process of the travel drive device 11 according to the present embodiment will be described with reference to FIGS.

  Here, the axle housing 12 is formed by dividing the motor housing cylinder 14 and the cylindrical spindle 15 in advance, and the cylindrical spindle 15 which is one of the divided parts has an inner peripheral side 1 as shown in FIG. The stage planetary gear speed reduction mechanism 25 is accommodated and assembled. Further, a carrier 39 of the second stage planetary gear speed reduction mechanism 34 is fixed to the flange portion 15C of the cylindrical spindle 15 with a bolt 40 or the like.

  In addition, the sun gear 35 is assembled to the carrier 39 in advance via the bearing 41, the coupling 33, and the like, and the planetary gear 37 is assembled using each support pin 38 and the like, whereby the ring gear 36 is assembled. The removed second stage planetary gear reduction mechanism 34 is assembled to the flange 15C side of the cylindrical spindle 15.

  Further, the outer ring side of the bearings 20 and 21 is fitted and attached to the inner peripheral side of the wheel mounting cylinder 19 in advance. In this state, the wheel mounting cylinder 19 is inserted along the direction indicated by the arrow D in FIG. 10 into the outer peripheral side of the cylindrical spindle 15, and the inner ring side of the bearings 20 and 21 is fitted to the cylindrical spindle 15 for mounting. .

  Further, the ring gear 36 is assembled together with the disk holding cylinder 22 in the direction of arrow E, and the planetary gear 37 and the ring gear 36 are engaged. Then, the end face of the ring gear 36 is brought into contact with the end face of the wheel mounting cylinder 19 as shown in FIG. 11, and in this state, the disk holding cylinder 22 and the ring gear 36 are attached to the wheel mounting cylinder 19 with a plurality of long bolts 23 (see FIG. 6). It is fixed so as to be integrated using

  Further, a retainer 60A of the sealing device 60 is fixed to the outer surface of the carrier 39 with a bolt or the like, so that the space between the disk holding cylinder 22 and the carrier 39 can be hermetically sealed. On the other hand, a retainer 54 of the sealing device 51 is fixed to one end face of the wheel mounting cylinder 19 with a bolt 53 or the like as shown in FIG.

  Next, prior to fixing the retainer 52 of the sealing device 51 to the connecting portion 15B of the cylindrical spindle 15, the shim plate 58 is disposed between the connecting portion 15B of the cylindrical spindle 15 and the annular protrusion 52B of the retainer 52. When the retainer 52 is fixed to the end surface of the connecting portion 15B with the bolt 57, the shim plate 58 is sandwiched and attached between the two. Then, by appropriately selecting the thickness or number of shim plates 58, the distance S (see FIG. 9) between the annular projection 52B of the retainer 52 and the end surface of the cylindrical spindle 15 is variably adjusted. .

  As a result, the cylindrical portion 52A of the retainer 52 is in contact with the inner ring of the bearing 20 at the tip side, and the axial set load (thrust load) on the bearing 20 is variably adjusted according to the thickness or number of shim plates 58. be able to. Further, the other bearing 21 disposed between the cylindrical spindle 15 and the wheel mounting cylinder 19 also has its inner ring abutting on the flange 15C side of the cylindrical spindle 15 as shown in FIGS. The set load (thrust load) of the bearing 21 can be variably adjusted according to the thickness or number of shim plates 58.

  As described above, the cylindrical spindle 15 is preinstalled with the wheel mounting cylinder 19, the speed reduction mechanism 24 (planetary gear speed reduction mechanisms 25, 34), the seal devices 51, 60, and the like. 11, FIG. 12 and FIG. 13 constitute the preliminary assembly 70 together with the wheel mounting cylinder 19, the speed reduction mechanism 24 and the like.

  Next, the cylindrical spindle 15 of the preliminary assembly 70 is fitted to the connecting portion 15B located on one side in the axial direction while the small diameter portion 14B side of the motor housing cylinder 14 is fitted as shown in FIGS. The motor housing cylinder 14 and the cylindrical spindle 15 are detachably connected using a plurality of bolts 16 (see FIG. 14). After that, the electric motor 17 is assembled in the motor housing cylinder 14, and the traveling drive device 11 is assembled as shown in FIG.

  Thus, according to the present embodiment, by dividing the cylindrical axle housing 12 into the motor housing cylinder 14 and the cylindrical spindle 15, the heavy and long axle housing 12 can be reduced in size and weight. It can be formed by the members (motor housing cylinder 14 and cylindrical spindle 15), and the labor and time spent for obtaining materials, machining, inspection after processing, etc. can be surely reduced, and the handleability etc. can be greatly improved. it can.

  In addition, a preliminary assembly 70 is configured by assembling the wheel mounting cylinder 19 and the speed reduction mechanism 24 in advance on such a cylindrical spindle 15, and the connecting portion of the cylindrical spindle 15 in the state of the preliminary assembly 70. 15B is configured to be detachably connected to the small diameter portion 14A side of the motor housing cylinder 14 using a bolt 16 or the like.

  For this reason, the pre-assembly work for assembling the wheel mounting cylinder 19 and the speed reduction mechanism 24 and the like to the cylindrical spindle 15 can be easily performed without assembling a particularly large scaffold or the like, and the burden on the operator is greatly reduced. can do. Then, by connecting the cylindrical spindle 15 to the motor housing cylinder 14 in the state of the preliminary assembly 70, the axle housing 12 can be assembled, and the entire apparatus can be efficiently assembled.

  Further, the sealing device 51 that seals between the rotating wheel mounting cylinder 19 and the non-rotating cylindrical spindle 15 includes a stationary retainer 52 with a connecting portion 15B of the cylindrical spindle 15 and a small diameter portion 14B of the motor housing cylinder 14. The two are connected and attached by a plurality of bolts 16 or the like.

  Accordingly, even when maintenance work such as seal replacement is performed at a work site such as a mining site, the motor housing cylinder 14 is simply removed from the cylindrical spindle 15 via the bolt 16 or the like, for example, as shown in FIG. Maintenance, inspection, etc. can be easily performed by exposing the device 51 to the outside. When the O-ring 55 or the like of the sealing device 51 is exchanged, the O-ring 55 can be easily replaced by removing the stationary retainer 52 with a bolt 57 or the like as shown in FIG.

  For this reason, it is not necessary to disassemble the preliminary assembly 70 composed of the cylindrical spindle 15, the wheel mounting cylinder 19, the speed reduction mechanism 24, etc. for exchanging seals, and the workability during maintenance is greatly improved. Can do. The sealing device 51 can reliably seal the space between the rotating wheel mounting cylinder 19 and the non-rotating cylindrical spindle 15, and can prevent the lubricating oil 100 in the annular space C from leaking. It is possible to prevent rainwater and earth and sand from entering.

  Moreover, a shim plate 58 is provided between the connecting portion 15B of the cylindrical spindle 15 and the retainer 52, and the adjustment of the set load for the bearings 20 and 21 is variably adjusted according to the thickness or number of the shim plates 58. Since it is configured, such a set load adjustment operation can be easily performed only by removing the motor housing cylinder 14 from the cylindrical spindle 15, and from the cylindrical spindle 15, the wheel mounting cylinder 19, the speed reduction mechanism 24, and the like. It is not necessary to disassemble the preliminary assembly 70 to adjust the set load of the bearings 20 and 21, and the workability at the time of maintenance can be greatly improved.

  Further, when mounting or removing the bearings 20 and 21 on the cylindrical spindle 15 or the like, the wheel is moved in the direction indicated by the arrow D shown in FIG. 10 from one axial direction side (the connecting portion 15B side) of the cylindrical spindle 15. The bearings 20 and 21 can be attached to the outer peripheral side of the cylindrical spindle 15 together with the mounting cylinder 19.

  For this reason, it is not necessary to attach and remove the bearings 20, 21 and the like from the other axial side of the cylindrical spindle 15, and an annular flange larger than the inner diameter of the bearings 20, 21 is located at the other axial side. The part 15C can be formed integrally. The reaction force receiving portion that receives the reaction force of the speed reduction mechanism 24 or the like can be configured by the flange portion 15 </ b> C of the cylindrical spindle 15.

  As a result, it is not necessary to provide a reaction force receiving portion separately from the cylindrical spindle 15, and the number of parts can be reduced to improve workability during assembly. Further, by increasing the outer diameter of the flange portion 15C, a more stable reaction force receiving portion can be configured, and the reaction force from the speed reduction mechanism 24 and the like can be received with sufficient strength.

  Moreover, when mounting or replacing the bearings 20 and 21 on the outer peripheral side of the cylindrical spindle 15, the reduction mechanism 24 or the like is assembled to the cylindrical spindle 15 as shown in FIG. Attachment and removal work of the bearings 20 and 21 can be easily performed from the connecting part 15B side of the spindle 15, and workability during assembly and maintenance can be improved.

  In the present embodiment, the first reduction gear housing space A is formed inside the cylindrical spindle 15 and the first stage carrier 30 is fixedly provided in the cylindrical spindle 15. The first stage planetary gear speed reduction mechanism 25 can be accommodated in the cylindrical spindle 15 in a compact manner, and the rotation of the carrier 30 can be restrained by the cylindrical spindle 15.

  For this reason, the first stage planetary gear speed reduction mechanism 25 can be configured to extract the reduced speed rotation from the ring gear 27 without rotating the heavy carrier 30, and the center of gravity position can be increased in manufacturing the carrier 30. This eliminates the need for special management. Thereby, workability | operativity and productivity at the time of manufacturing the carrier 30 can be improved.

  Also, the second stage planetary gear speed reduction mechanism 34, which is the final stage, is fixed to the cylindrical spindle 15 with a bolt 40 or the like to fix the carrier 39 to the final stage as a lid that covers the open end side of the cylindrical spindle 15. The carrier 39 can be used, and the cylindrical spindle 15 can be assembled by the carrier 39 as a covered cylindrical body having a sturdy structure. Further, the rotation of the carrier 39 at the final stage can also be restricted, and the workability during manufacturing, the workability during assembly, and the like can be improved.

  As a result, the carriers 30 and 39 of the planetary gear speed reduction mechanisms 25 and 34 can be utilized as strength members for the cylindrical spindle 15 and the like, and the strength and rigidity of the entire apparatus can be increased. Further, this makes it possible to reduce the thickness of the cylindrical spindle 15 and to reduce the weight of the entire apparatus. Since the first stage planetary gear speed reduction mechanism 25 can be accommodated in the cylindrical spindle 15, the axial length (full length) of the entire travel drive device 11 can be shortened, and the entire device can be downsized. The weight can also be reduced.

  On the other hand, the last stage carrier 39 is used as a cover for covering the opening end side of the cylindrical spindle 15, and the disc brake 46 is fixed on the outer surface of the carrier 39 with a bolt 47 or the like. The disc brake 46 can be installed at a position on the inner side in the radial direction of the wheel 7 (the wheel mounting cylinder 19) and on the outer side in the axial direction of the cylindrical spindle 15.

  For this reason, at the time of maintenance of the disc brake 46, for example, the wheel cap 7C (see FIG. 3) of the rear wheel 7 is simply removed from the outside in the axial direction, without removing the tire 7A, the rim 7B, etc. of the rear wheel 7, etc. Maintenance and inspection of the disc brake 46 can be easily performed from the outside in the axial direction of the holding cylinder 22 (the wheel mounting cylinder 19), and workability during maintenance can be improved.

  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 includes the first stage planetary gear speed reduction mechanism 25 and the second stage planetary gear speed reduction mechanism 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 one or more planetary gear speed reduction mechanisms, or a speed reduction mechanism other than the planetary gear speed reduction mechanism may be used.

  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. It is a front view which expands and shows the rear wheel in FIG. FIG. 4 is a cross-sectional view of the traveling drive device on the rear wheel side as viewed from the direction of arrows IV-IV in FIG. 3 with the wheel cap removed. FIG. 5 is an enlarged cross-sectional view illustrating a motor housing cylinder, a cylindrical spindle, a wheel mounting cylinder, a planetary gear reduction mechanism, and the like in FIG. It is a left view of FIG. 5 which expands and shows a disk brake etc. It is sectional drawing which expands and shows the wheel attachment cylinder and planetary gear reduction mechanism etc. in FIG. It is sectional drawing which expands further and shows the planetary gear reduction mechanism etc. in FIG. It is sectional drawing which expands and shows the sealing apparatus etc. which were provided between the cylindrical spindle in FIG. 7, and a wheel attachment cylinder. It is sectional drawing which shows the state in the middle of assembling | attaching a wheel attachment cylinder, a planetary gear reduction mechanism, etc. to a cylindrical spindle. It is sectional drawing which shows the state which assembles a preliminary assembly from a cylindrical spindle, a wheel attachment cylinder, a planetary gear reduction mechanism, etc. It is sectional drawing which shows the state which connects a motor accommodating cylinder with the cylindrical spindle of a preliminary assembly. FIG. 13 is a right side view of the preliminary assembly as viewed from the direction of arrows XIII-XIII in FIG. 12. It is the left view which looked at the motor accommodating cylinder from the arrow XIV-XIV direction in FIG.

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 Traveling drive device 12 Axle housing 13 Suspension cylinder 14 Motor accommodating cylinder (drive source accommodating part)
15 cylindrical spindle 15B connection part (connection position)
15C buttock (reaction force receiving part)
16, 31, 40 volts 17 Electric motor (drive source)
18 Rotating shaft 19 Wheel mounting cylinder 20, 21 Bearing 22 Disk holding cylinder 22A 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 42 Inner cap 43, 44 Brake piping 46 Disc brake (brake means)
51 Sealing device (sealing means)
52, 54 Retainer 55 O-ring (seal member)
56 Seal ring 58 Shim plate (Set load adjuster)
61 Wedge member 62 Undulating cylinder 70 Preliminary assembly

Claims (3)

A cylindrical axle housing that is attached to the body of the dump truck in a non-rotating state, a drive source that is provided on the axle housing and that rotates the rotating shaft, and is provided rotatably on the outer peripheral side of the axle housing via a bearing. Traveling of a dump truck comprising a wheel mounting cylinder to which a wheel is mounted, and a speed reduction mechanism provided between the wheel mounting cylinder and the axle housing to transmit the rotation of the rotary shaft to the wheel mounting cylinder at a reduced speed. In the drive device,
The axle housing includes a cylindrical drive source accommodating portion that accommodates the drive source therein, and a cylindrical spindle that is disposed radially inside the wheel mounting cylinder and rotatably supports the wheel mounting cylinder via the bearing. And divided into
The cylindrical spindle is configured to be detachably connected to the drive source accommodating portion at an axial end portion ;
A preliminary assembly is configured by pre-assembling the wheel mounting cylinder and the speed reduction mechanism on the cylindrical spindle, and the cylindrical spindle is connected to the drive source accommodating portion in a state of the preliminary assembly.
Sealing means for sealing the space between the wheel mounting cylinder and the cylindrical spindle and allowing the wheel mounting cylinder to rotate around the cylindrical spindle is provided at a connecting position between the cylindrical spindle and the drive source accommodating portion. Provided,
The dump truck travel drive device characterized in that the seal means is configured to be exposed to the outside from the cylindrical spindle when the cylindrical spindle is removed from the drive source accommodating portion in the state of the preliminary assembly. . The set load adjusting section for adjusting the set load of the bearing disposed between the wheel mounting cylinder and the cylindrical spindle is provided in the vicinity of the connection position between the cylindrical spindle and the drive source accommodating section. 1. A traveling drive device for a dump truck according to 1 . 3. The structure according to claim 1, wherein the mounting and dismounting of the bearing with respect to the cylindrical spindle is performed from an end side closer to a connection position with the drive source accommodating portion on both axial sides of the cylindrical spindle. The dump truck travel drive device described.

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