JP4745813B2 - Planetary gear reducer - Google Patents

Description

  The present invention relates to a planetary gear reduction device that is preferably used for a travel drive device of a dump truck that transports crushed stones mined in, for example, an open-pit mine, a quarry, or a mine.

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

  In this case, the reduction gear mechanism of each stage includes a sun gear positioned at the center thereof, a ring gear that surrounds the sun gear from the radially outer side and has inner teeth formed on the inner peripheral surface, and inner teeth of the ring gear. A plurality of planetary gears that mesh with the sun gear and transmit the rotation of the sun gear to the ring gear, and a carrier that rotatably supports each planetary gear via a support pin.

  The multi-stage reduction gear mechanism is configured such that each planetary gear rotates or revolves around the sun gear around the support pin, thereby reducing the rotation output of a rotation source such as a hydraulic motor, for example. Tell the cylinder (wheel). As a result, a large rotational torque can be transmitted to the driving wheels such as the front wheels or the rear wheels of the vehicle, and the transport performance of the dump truck (vehicle) can be improved.

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

  In the prior art described above, the reduction gear mechanism for increasing the rotational torque of the vehicle (drive wheel) is constituted by a sun gear, a ring gear, a plurality of planetary gears, a carrier, and the like. The carrier is configured to rotatably support a plurality of planetary gears that revolve while rotating according to the rotation of the sun gear, and to take out the revolutions of the planetary gears as rotation output.

  However, since the carrier used for such a reduction gear mechanism is formed as a heavy article of several hundred kg (kilograms) using a means such as casting, the center of gravity of the carrier is slightly deviated from the center of rotation. In other words, a large vibration is generated when the carrier rotates as the planetary gear rotates.

  For this reason, in the prior art, it is necessary to strictly manage the center of gravity position in manufacturing the carrier, and it becomes difficult to distribute the load of the support pins and the plurality of planetary gears assembled to the carrier. There is a problem that productivity at the time and workability at the time of assembly cannot be improved.

  In addition, the carrier needs to secure sufficient rigidity for rotatably supporting a plurality of planetary gears, and for this purpose, the carrier is formed as a sturdy heavy object. However, in a reduction gear mechanism of a type in which the carrier rotates, the carrier cannot be used as a strength member for a casing (for example, an axle housing) that is a non-rotating part of the traveling drive device, and the weight of the carrier is large. It has become.

  In addition, in the case of the prior art, the reduction gear mechanism is arranged at a position protruding outward from the casing (axle housing) of the apparatus in the axial direction. For this reason, there exists a problem that the axial direction length (full length) of the whole traveling drive apparatus becomes long, the whole becomes large and weight increases.

  On the other hand, in a planetary gear reduction device of a type that fixes a carrier in a non-rotatable manner (carrier fixed type), for example, a gear coupling that transmits rotation by spline coupling between a first-stage ring gear and a second-stage sun gear. There is a configuration in which the rotation of the ring gear accompanying the rotation of the first stage planetary gear is transmitted to the second stage sun gear by gear coupling.

  Further, since a large torque accompanying rotation transmission acts on the spline coupling portion between the ring gear and the gear coupling, for example, the spline coupling portion of the gear coupling is held in a retaining state with respect to the ring gear. There is a structure in which the stopper member is fixed to the end face of the ring gear or the like using a bolt (see a comparative example shown in FIG. 10 described later).

  However, in this case, since the planetary gear meshes with the inner teeth of the ring gear and a large torque is applied due to the rotation transmission, the ring gear is elastically deformed so that the ring gear is twisted with respect to the gear coupling (spline coupling portion). There is. When such elastic deformation is repeated, the bolt that secures the retaining member to the end face of the ring gear is liable to be loosened due to the influence. In the worst case, the retaining member falls off together with the bolt. There is a problem such as.

  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 fix the carrier of the reduction gear mechanism to the casing, thereby restraining the rotation of the carrier and manufacturing the carrier. An object of the present invention is to provide a planetary gear speed reduction device that eliminates the need for special management of the center of gravity and so on, and can improve workability and productivity in manufacturing the carrier.

  Another object of the present invention is to constrain the rotation of the carrier so that the carrier can be used as a strength member of the casing, and the overall size and weight can be reduced. It is an object of the present invention to provide a planetary gear speed reduction device that can improve the above-described characteristics.

  Furthermore, another object of the present invention is that a gear coupling provided between the ring gear and the sun gear of the next stage can be kept in a state of being prevented from being pulled out with respect to the ring gear for a long period of time, thereby suppressing bolt loosening and the like. Another object of the present invention is to provide a planetary gear reduction device that can improve reliability and safety.

  In order to solve the above-described problems, the present invention includes a cylindrical casing and a plurality of reduction gear mechanisms provided in the casing, and the reduction gear mechanisms of each stage are arranged on the center side thereof. A gear, a ring gear having inner teeth formed on the inner peripheral surface, a planetary gear that meshes with the inner teeth of the ring gear and the sun gear and transmits rotation of the sun gear to the ring gear, and rotatably supports the planetary gear The present invention is applied to a planetary gear speed reduction device that is configured by a carrier that performs the same.

A feature of the configuration adopted by the invention of claim 1 is that at least the first reduction gear mechanism among the reduction gear mechanisms is provided with the carrier in a non-rotating state in the casing, and the rotation of the ring gear. Is connected to the sun gear of the next stage using a gear coupling, and the gear coupling includes a spline that meshes with the inner peripheral side of the ring gear. A coupling portion is formed, and between the gear coupling and the ring gear, the tip end side is locked to the inner peripheral side of the ring gear, and the spline coupling portion of the gear coupling is held in a state of being secured against the ring gear. a locking plate provided, locking plate fixed to with bolts to the gear coupling in locked state on the inner peripheral side of the ring gear Lies in that the configuration and the.

According to a second aspect of the present invention, the ring gear of the first-stage reduction gear mechanism has female spline teeth meshing with the gear coupling and a locking groove extending in the circumferential direction of the ring gear, The spline coupling portion of the gear coupling is a male spline tooth that meshes with the female spline tooth of the ring gear, and the front end side of the locking plate has a claw portion that locks in the locking groove of the ring gear. It is set to.

Furthermore, according to the invention of claim 3, wherein the gear coupling is constituted by an outer peripheral side splined circle dish-shaped annular body splined to the inner circumference side to the ring gear to the next sun gear, the engagement A plurality of stop plates are provided at intervals on the outer peripheral side of the annular body.

As described above, according to the first aspect of the present invention, the first-stage carrier is provided in the casing in a non-rotating state, and, for example, between the first-stage ring gear and the second-stage sun gear, And a gear coupling that transmits rotation at the same time, and a spline coupling portion that meshes with the inner peripheral side of the ring gear is formed in the gear coupling, and the tip side is between the gear coupling and the ring gear. a spline coupling portion of the locked the gear coupling to the inner circumference side of the ring gear against the ring gear is provided a locking plate for retaining the retaining state, the locking plate is engaged with the inner periphery of the ring gear since the configuration and to have you fixed with bolts to the gear coupling in sealed state, the ring gear is gear coupled by meshing with the planetary gears (torque transfer) (spline formation Even when elastically deformed so twisted relative parts), the locking plate for retaining fixed with bolts to the gear coupling, the impact of the elastic deformation of the ring gear extends over directly the Disappear. As a result, it is possible to suppress the occurrence of slack in the bolt that fixes the locking plate to the gear coupling, thereby improving the reliability and safety of the device.

  In addition, since the first stage carrier can be provided in the casing in a non-rotating state and the rotation of the carrier can be restrained by the casing, the center of gravity position is managed specially in manufacturing the carrier as in the prior art. This eliminates the need for load distribution of the plurality of support pins and planetary gears assembled to the carrier. The carrier can be formed into a sturdy structure with sufficient rigidity to rotatably support a plurality of planetary gears, and the carrier can be utilized as a strength member for the casing. Can be increased.

  Therefore, workability and productivity in manufacturing the carrier can be improved, and workability in assembling the planetary gear reduction device can be improved. In addition, since the carrier can be utilized as a strength member for the casing, the strength and rigidity of the entire apparatus can be increased, and the thickness of the casing can be reduced thereby reducing the weight of the entire apparatus. It is also possible to reduce the size and weight.

Also, the locking plate for locking in a retaining state Li ring gear, so that a structure for securing with bolts to the gear coupling, the ring gear under the influence of the torque transmission between the planet gear wrenched relative to the gear coupling Even when elastically deformed, the influence of this elastic deformation can be prevented from reaching the locking plate. That is, the locking plate is only engaged with the ring gear, will not be affected due to the elastic deformation of the ring gear extends over directly to the gear coupling (locking plates and bolts). For this reason, even when the ring gear repeats the above-described elastic deformation, it is possible to suppress the occurrence of slack or the like in the bolt that fastens the locking plate to the gear coupling.
According to the invention of claim 2, the first-stage ring gear can be provided with female spline teeth meshing with the gear coupling and a locking groove extending in the circumferential direction of the ring gear. The spline coupling portion of the ring can be a male spline tooth that meshes with the female spline tooth of the ring gear, and the front end side of the locking plate is a claw portion, and the claw portion is locked in the locking groove of the ring gear. be able to.

Furthermore, according to the invention described in claim 3, the gear coupling is constituted by a circular plate-like annular body in which the outer peripheral side is spline-coupled to the ring gear and the inner peripheral side is spline-coupled to the next-stage sun gear. Since a plurality of locking plates are provided at intervals on the outer peripheral side, a plurality of gear plates made of a disc-shaped annular body are spline-coupled to the inner peripheral side of the ring gear and a plurality of spaced apart circumferentially are provided. By using the locking plate , both the spline coupling portions can be held in the retaining state.

  Hereinafter, a planetary gear reduction device according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings, taking as an example a case where the planetary gear reduction device is applied to a traveling drive device for a dump truck.

  Here, FIG. 1 to FIG. 9 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 undulation cylinder 64, 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. The travel drive device 11 includes an axle housing 12, an electric motor 17, a wheel mounting cylinder 19, a reduction gear device 24, and the like which will be described later. Yes. The travel drive device 11 decelerates the rotation of the electric motor 17 by the reduction gear device 24 and travels and drives the rear wheel 7 as a drive 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 housing cylinders as rotation source housing portions provided at both ends of the suspension cylinder 13, and each motor housing cylinder 14 is formed as 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 FIG. 4, a cylindrical spindle 15 described later is detachably fixed to the motor accommodating cylinder 14 on the side of the small diameter portion 14B via a bolt 16 or the like, and the inside thereof is accommodated in a first reduction gear housing described later. It is space A. The motor housing cylinder 14 houses an electric motor 17 (to be described later) serving as a rotation source of the rear wheel 7.

  Reference numeral 15 denotes a cylindrical spindle as a casing constituting the tip portion of the axle housing 12, and the cylindrical spindle 15 is formed of a large-diameter stepped cylindrical body having an inner diameter of about 80 to 100 cm, for example. Is formed as a first reduction gear housing space A for housing the first reduction gear mechanism 25 as shown in FIGS. 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. 4 and 6, an annular flange portion 15 </ b> C protruding outward in the radial direction is integrally formed.

  A final stage carrier 43 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.

  The cylindrical spindle 15 is provided with fixed carriers 30 and 43 of speed reduction gear mechanisms 25 and 38 as will be described later. Thus, the cylindrical spindle 15 is assembled as a covered cylindrical body having a sturdy structure, and the wheel mounting cylinder 19 (rear wheel 7) can be supported from the inner side with high rigidity (strength) on the outer peripheral side thereof. The cylindrical spindle 15 has a function of receiving rotational reaction force and the like generated in reduction gear mechanisms 25 and 38, which will be described later, with sufficient strength via the carriers 30 and 43.

  Here, the first reduction gear housing space A is surrounded by a motor housing cylinder 14 and a cylindrical spindle 15 as shown in FIG. 4, and one side (inside) in the axial direction is closed by an electric motor 17 or the like described later, The other side (outer side) in the axial direction is covered with a gear coupling 34 and the like which will be described later. A reduction gear mechanism 25, which will be described later, is accommodated in the reduction gear accommodating space A.

  Reference numeral 17 denotes an electric motor as a rotation 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 distal end side of the rotating shaft 18 extends through the inner peripheral side of the sun gear 26 in the axial direction as shown in FIGS. 4, 6, and 7. Opposite (facing). When an axial thrust load is applied to the rotary shaft 18 due to the rotation of the electric motor 17, the thrust receiver 32 receives the thrust load and regulates the axial displacement of the rotary shaft 18, thereby rotating the rotary shaft. The rotation of 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 FIGS. 4 and 6, the wheel mounting cylinder 19 has a one-side cylinder portion 19 </ b> A extending in the axial direction between the bearings 20 and 21, and an end portion of the one-side cylinder portion 19 </ b> A toward a ring gear 40 described later. The inner peripheral surface 19B1 extends in the axial direction, and is formed as a stepped cylindrical body by the other side cylindrical portion 19B formed with an inner diameter larger than the one side cylindrical 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, a retainer 59 of a seal device 57, 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 40 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 47 or the like, whereby the wheel mounting cylinder 19 is connected to the ring gear 40. And rotate together. That is, the wheel mounting cylinder 19 is transmitted via the ring gear 40 the rotation that has become a large torque by decelerating the rotation of the electric motor 17 by the reduction gear device 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 40 is formed as a second reduction gear accommodating space B in which a second-stage reduction gear mechanism 38 described later is accommodated. The second reduction gear housing space B is surrounded by a gear coupling 34 and the like, which will be described later, between the first reduction gear housing space A located on one side in the axial direction and the other side (outside) in the axial direction. ) Is covered with a carrier 43, an inner cap 46, a sealing device 62 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 portion of the annular space C has a lubricating oil 100 (FIG. 4). In FIG. 6, the liquid level is indicated by a two-dot chain line). 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 peripheral surface located between the bearing mounting sections 19C and 19D, which gradually increases in diameter from the bearing 21 side toward the bearing 20 side as shown in FIGS. It is formed as a tapered guide surface (hereinafter referred to as an inclined surface 19F). The lubricating oil 100 in the annular space C is guided toward the later-described discharge pipe 61A by the inclined surface 19F. Further, on the one side (inside) in the axial direction of the wheel mounting cylinder 19, a seal device 57 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 (the 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 FIGS. 4 and 6, and the inner diameter of the other side cylinder portion 19B. It is formed smaller than (inner peripheral surface 19B1).

  Reference numeral 22 denotes a disk holding cylinder which constitutes a part of the wheel mounting cylinder 19 together with the ring gear 40. The disk holding cylinder 22 is described later at a position on the outer side in the axial direction of the wheel mounting cylinder 19 as shown in FIGS. It is attached with the ring gear 40 in between and is detachably fixed to the wheel mounting cylinder 19 by using long bolts 47 described later.

  As shown in FIG. 5, a ring-shaped (annular) disk 23 is secured to the disk holding cylinder 22 and attached in a non-rotating state. The disk 23 is given a braking force by a disk brake 51 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.

  A reduction gear device 24 is provided between the cylindrical spindle 15 and the wheel mounting cylinder 19 and constitutes a planetary gear reduction device together with the cylindrical spindle 15. The reduction gear device 24 is a first-stage reduction gear described later. The mechanism 25 and the second-stage reduction gear mechanism 38 are configured to decelerate and transmit the rotation of the rotary shaft 18 to the wheel mounting cylinder 19 on the rear wheel 7 side.

  Reference numeral 25 denotes a first-stage reduction gear mechanism provided in the cylindrical spindle 15 of the axle housing 12, and the reduction gear mechanism 25 is arranged on the center side as shown in FIGS. 3, 4, 6 and 7. And a sun gear 26 splined to the front end side of the rotating shaft 18, a ring gear 27, a planetary gear 28, a support pin 29, a carrier 30, and the like, which will be described later.

  Reference numeral 27 denotes a first-stage ring gear that constitutes a part of the reduction gear mechanism 25. The ring gear 27 radiates the sun gear 26, the planetary gear 28, the carrier 30 and the like in the radial direction as shown in FIGS. It is formed as a short cylindrical gear (ring body) that surrounds from the outside. The first-stage ring gear 27 is disposed on the inner peripheral side of the cylindrical spindle 15 so as to be relatively rotatable, and a radial clearance S (for example, about 2 to 5 mm) shown in FIGS. Is formed.

  Here, on the inner peripheral side of the ring gear 27, an inner tooth 27A meshing with a planetary gear 28 described later, a female spline tooth 27B meshing with a male spline tooth 34B of a gear coupling 34 described later, and the female spline tooth 27B. 27C formed between the inner teeth 27A and the inner teeth 27A, and a locking groove 27D that is recessed on the end side of the female spline teeth 27B spaced from the step 27C and extends in the circumferential direction of the ring gear 27. ing. The locking groove 27D is disposed at a position so as to sandwich male spline teeth 34B of a gear coupling 34, which will be described later, between the stepped portion 27C and both sides in the axial direction. The locking plate 35 is locked.

  Reference numeral 28 denotes a plurality of planetary gears (only one is shown in FIG. 4) constituting the first-stage reduction gear mechanism 25 together with the sun gear 26, the ring gear 27, and the like. These planetary gears 28 are provided with support pins 29 described later. The bearing 30 </ b> A is provided between the planetary gear 28 and the support pin 29. The planetary gear 28 meshes with the sun gear 26 and the internal teeth 27 </ b> A of the ring gear 27 and rotates according to the rotation of the sun gear 26, thereby transmitting this rotation (rotation) to the ring gear 27.

  In this case, in the first-stage reduction gear mechanism 25, the revolution of the planetary gear 28 (rotation of the carrier 30) is restricted by fixing a carrier 30 described later to the cylindrical spindle 15. For this reason, when the sun gear 26 is integrally rotated by the rotating shaft 18 of the electric motor 17, the rotation of the sun gear 26 is converted into the rotation of the planetary gear 28. The first-stage reduction gear mechanism 25 takes out the rotation (rotation) of the planetary gear 28 as a reduced rotation of the ring gear 27, and the rotation of the ring gear 27 through the gear coupling 34, which will be described later. This is transmitted to the reduction gear mechanism 38.

  Reference numeral 29 denotes a support pin that rotatably supports the planetary gear 28 via a bearing 28A. The support pin 29 is attached by fitting both end sides thereof into annular plate portions 30A and 30B of the carrier 30 described later, and rotating the respective pins. It extends parallel to the shaft 18. A planetary gear 28 is rotatably provided on the outer peripheral side of the support pin 29 through two bearings 28A and 28A as shown in FIG.

  As shown in FIGS. 6 and 7, the support pin 29 is formed with an oil passage 29A for lubricating oil, and the oil passage 29A has a conduit for lubricating oil extending in the axial direction in the cylindrical spindle 15 (see FIG. 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.

  30 is a first-stage carrier used for the first-stage reduction gear mechanism 25, and the carrier 30 includes two annular plate portions 30A that are separated from each other in the axial direction of the rotary shaft 18 as shown in FIG. 30B and a substantially fan-shaped support column 30C (only one shown) integrally connected at three locations in the circumferential direction between the annular plate portions 30A and 30B, and one of the annular plate portions 30A and 30B. The annular plate portion 30A on the side is formed with 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 support columns 30 </ b> C. 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 a plurality of bolts 31 on the outer peripheral side thereof. Thereby, the first stage carrier 30 is provided in a non-rotating state in the cylindrical spindle 15 as a casing, and is accommodated in the reduction gear accommodating space A of the cylindrical spindle 15 together with a plurality of planetary gears 28 and the like. It is.

  Reference numeral 32 denotes a thrust receiver for receiving a thrust load from the rotary shaft 18. The thrust receiver 32 is located on the center side of the carrier 30 as shown in FIGS. 6 and 7, and is located on the inner peripheral side of the annular plate portion 30B. Are rotatably provided via a thrust bearing 32A (hereinafter referred to as bearing 32A). The thrust receiver 32 receives the thrust load from the rotary shaft 18 through the bearings 32A and the like, and smoothes the rotation of the sun gear 26.

  That is, when an axial thrust load is applied to the rotary shaft 18 by the rotation of the electric motor 17, the end surface on the front end side of the rotary shaft 18 contacts the thrust receiver 32, so that the thrust receiver 32 is attached to the rotary shaft 18. Follow and rotate. The thrust receiver 32 receives the thrust load at this time on the contact surface side and regulates the axial displacement of the rotary shaft 18.

  Reference numeral 33 denotes a lubricant guide provided in the annular plate portion 30B of the carrier 30. The lubricant guide 33 is positioned above the thrust receiver 32 and has a guide hole 33A for the lubricant formed in the annular plate portion 30B. , And a lubricating oil pocket 33B disposed between the guide hole 33A and the thrust receiver 32.

  When the lubricating oil guide 33 is scraped up by the ring gear 27 onto the liquid surface of the lubricating oil 100 and adheres to the annular plate portion 30B of the carrier 30, the lubricating oil guide 33 flows down due to natural dripping (self-weight) or the like. Further, this lubricating oil is guided to the thrust receiver 32 through the guide hole 33A and the lubricating oil pocket 33B, and the bearing 32A and the like are kept in a lubricating state.

  Here, as shown in FIG. 7, the lubricant pocket 33B is integrally formed with the annular plate portion 30B of the carrier 30, and protrudes (swells) in a pocket shape from the outer surface of the annular plate portion 30B. As shown in FIG. 7, the lubricating oil pocket 33B covers the bearing 32A of the thrust receiver 32 with a gap from the outside in the axial direction, and supplies (greases) the lubricating oil collected inside to the bearing 32A. is there.

  34 is a gear coupling as a rotation transmission member provided between the first-stage ring gear 27 and the next-stage sun gear 39. The gear coupling 34 is connected to the first-stage reduction gear mechanism 25 and the second-stage gear mechanism 25. It is formed as a disk-shaped annular body positioned between the reduction gear mechanism 38 of the eye. Then, male spline teeth 34B as spline coupling portions that mesh with the female spline teeth 27B of the ring gear 27 are formed on the outer peripheral portion 34A of the gear coupling 34 as shown in FIG.

  The outer peripheral portion 34 </ b> A of the gear coupling 34 is such that the male spline teeth 34 </ b> B are retained from the female spline teeth 27 </ b> B of the ring gear 27 by a locking plate 35, which will be described later. On the other hand, female spline teeth 34D that are spline-coupled to a second-stage sun gear 39, which will be described later, are formed on the inner peripheral portion 34C of the gear coupling 34, as shown in FIG.

  The gear coupling 34 transmits the rotation of the first-stage ring gear 27 to the second-stage sun gear 39 and rotates the sun gear 39 integrally with the ring gear 27 at the same speed. In addition, between the outer peripheral part 34A and the inner peripheral part 34C of the gear coupling 34, the lubricating oil 100 in the first reduction gear housing space A is directed toward the second reduction gear housing space B, and the gear coupling is performed. A plurality of oil holes (not shown) to be circulated before and after 34 may be formed.

  Reference numeral 35 denotes a locking plate as a holding member provided on the outer peripheral portion 34A of the gear coupling 34. The locking plate 35 is formed as a substantially rectangular flat plate as shown in FIGS. Are detachably fixed to the outer peripheral portion 34A of the gear coupling 34 via a washer 37 and the like. Further, a claw portion 35A that protrudes toward the locking groove 27D of the ring gear 27 is provided on the distal end side of the locking plate 35 as shown in FIG.

  The claw portion 35A of the locking plate 35 is locked in the locking groove 27D, thereby sandwiching the male spline teeth 34B of the gear coupling 34 between the stepped portion 27C of the ring gear 27, and the male spline teeth 34B. Is held against the female spline teeth 27 </ b> B of the ring gear 27.

  In this case, two or more locking plates 35 are provided on the outer peripheral portion 34A of the gear coupling 34 so as to be spaced apart from each other in the circumferential direction, and the male spline teeth 34B of the gear coupling 34 are inserted into the female splines of the ring gear 27 at the respective positions. The tooth 27B is held in a retaining state. As a result, the male spline teeth 34B of the gear coupling 34 continue to mesh with the female spline teeth 27B of the ring gear 27 in a stable state.

  Reference numeral 38 denotes a second-stage reduction gear mechanism that is the final stage employed in the present embodiment, and the reduction gear mechanism 38 is provided between the cylindrical spindle 15 and the wheel mounting cylinder 19 in the first-stage reduction gear mechanism 25. And the first stage reduction gear mechanism 25, together with the first reduction gear mechanism 25, decelerates the rotation of the rotary shaft 18 to generate a large rotational torque in the wheel mounting cylinder 19.

  In this case, the second-stage reduction gear mechanism 38 includes a cylindrical sun gear 39 that is arranged coaxially with the rotary shaft 18 and rotates integrally with the gear coupling 34, and internal teeth 40 </ b> A of the sun gear 39 and the ring gear 40. (See FIG. 6), for example, three planetary gears 41 (only one is shown) that rotate according to the rotation of the sun gear 39, and each planetary gear 41 is rotatably supported via a support pin 42. It is comprised by the carrier 43 grade | etc.,.

  The outer stage of the second stage carrier 43 is fixed to the flange 15C of the cylindrical spindle 15 in a non-rotating state and detachably using a bolt 44 (see FIG. 6) or the like. Accordingly, the carrier 43 also serves as a lid that covers the reduction gear housing space A from the outside at the opening end of the cylindrical spindle 15. Further, as shown in FIG. 6, a bearing 45 or the like is provided on the inner peripheral side of the carrier 43, and this bearing 45 supports the sun gear 39 so as to be rotatable from both sides in the axial direction between the gear coupling 34. ing.

  On the other hand, the second-stage ring gear 40 is formed as a short cylindrical body (ring body) that surrounds the sun gear 39, the planetary gear 41, the support pin 42, the carrier 43, and the like from the outside in the radial direction. Between the disk holding cylinder 22, a long bolt 47 described later is integrally fixed. And the inner gear 40A (refer FIG. 6) which meshes with each planetary gear 41 is formed in the inner peripheral side of the ring gear 40. As shown in FIG.

  Here, in the second-stage reduction gear mechanism 38 as the final stage, the revolution of the planetary gear 41 (the rotation of the carrier 43) is restrained by fixing the carrier 43 to the cylindrical spindle 15. Then, when the sun gear 39 rotates together with the gear coupling 34, the second-stage reduction gear mechanism 38 converts the rotation of the sun gear 39 into the rotation of the plurality of planetary gears 41, and this rotation (rotation). Is taken out from the ring gear 40 as a decelerated rotation.

  That is, the ring gear 40 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 rear wheel 7 side is transmitted with a large output rotational torque reduced in two stages by the first-stage reduction gear mechanism 25 and the second-stage reduction gear mechanism 38. .

  Further, as shown in FIG. 6, an oil passage 42 </ b> A is formed in the support pin 42 of each planetary gear 41, and a later-described supply pipe 53 is connected to the oil passage 42 </ b> A from the outside of the carrier 43. Then, the lubricating oil 100 guided from the supply pipe 53 into the oil passage 42A is supplied so as to be injected toward the bearing 41A of the planetary gear 41 and the tooth surfaces of the bearing 41A and the planetary gear 41 are lubricated. It is something to keep in.

  On the other hand, the carrier 43 of the reduction gear mechanism 38 is formed with an oil groove 43A extending upward and downward along the flange portion 15C of the cylindrical spindle 15 as shown in FIG. The inner side and the outer side in the radial direction of the carrier 43 are always in communication with each other through the oil groove 43A, and the lubricating oil 100 supplied into the first and second reduction gear housing spaces A and B is in the oil groove 43A. It distribute | circulates toward the position which becomes the lower side of the wheel attachment cylinder 19 via. Thereby, the liquid level of the lubricating oil 100 is made uniform in the cylindrical spindle 15 and the wheel mounting cylinder 19.

  Reference numeral 46 denotes an inner cap that covers the inner peripheral side of the carrier 43. The inner cap 46 is detachably provided on the inner peripheral side of the carrier 43 via a bolt as shown in FIG. The carrier 43 is held in a retaining state. The inner cap 46 covers the opening end side of the cylindrical spindle 15 together with the carrier 43 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 43. is there.

  47 are long bolts which are fixing means for fixing the disk holding cylinder 22 to the wheel mounting cylinder 19, and these long bolts 47 are arranged in the circumferential direction of the disk holding cylinder 22 as shown in FIG. It is attached with a predetermined interval. As shown in FIG. 6, the long bolt 47 is configured such that the disk holding cylinder 22 and the ring gear 40 are connected to the wheel mounting cylinder 19 in a state where the ring gear 40 is sandwiched between the wheel mounting cylinder 19 and the disk holding cylinder 22. It is detachably fixed to the side tube portion 19B.

  A brake pipe 48 is disposed extending in the axial direction in the cylindrical sun gear 35. The brake pipe 48 is attached to the inner cap 46 at the tip end side, and is drawn out from the inner cap 46 to the outside. Further, the base end side (one side) of the brake pipe 48 extends toward the first-stage carrier 30 through an axial liquid hole (not shown) formed in the first-stage carrier 30. It is connected to another brake pipe 49.

  Further, as shown in FIG. 4, the other brake pipe 49 extends in the reduction gear housing space A of the cylindrical spindle 15 in the axial direction, 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 49 toward the brake pipe 48.

  Further, the tip end side of the brake pipe 48 drawn out from the inner cap 46 is connected to a total of three branch pipes 50, 50,... (See FIG. 5) made of, for example, a flexible hose. These branch pipes 50 supply the brake hydraulic pressure from the brake pipe 48 side to each disk brake 51 described later.

  .. Are a plurality of disc brakes constituting a brake means together with the disc 23, and each disc brake 51 is externally (decelerated) on the second stage carrier 43 as a final stage as shown in FIG. It is attached from the outside of the machine housing space A) using bolts 52 or the like. Further, a total of three disc brakes 51 are provided at intervals in the circumferential direction of the disc 23 as shown in FIG.

  The disc brake 51 is supplied with the brake fluid pressure from the master cylinder through the brake pipes 49 and 48 and the branch pipes 50, so that the disc 23 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.

  53 are lubricating oil supply pipes, and these supply pipes 53 are connected to the oil passages 42A (see FIG. 6) of the support pins 42 at positions outside the carrier 43 as shown in FIG. ing. Further, these supply pipes 53 are connected to lubricating oil supply pipes (not shown) arranged in the sun gear 39, the carrier 30, the cylindrical spindle 15 and the like in substantially the same manner as the brake pipes 48 and 49 shown in FIG. It is connected. The lubricating oil from the supply pipe is supplied in an injection state into the oil passage 42 </ b> A of each support pin 42 through each supply pipe 53.

  54 is a return pipe provided outside the inner cap 46. This return pipe 54 is connected to the most downstream side of the supply pipe 53 as shown in FIG. 6 to return to the inside of the inner cap 46. The return oil (lubricating oil) is supplied to the bearing 45 and the like between the inner cap 46 and the sun gear 39 and then gradually dropped (dropped) in the reduction gear housing space B and stored.

  55 is a drain hole formed in the lowermost portion of the wheel mounting cylinder 19, and this drain hole 55 extends in the axial direction through the ring gear 40 and the disk holding cylinder 22, as shown in FIG. The plug 56 is detachably closed. When the plug 56 is removed, the lubricating oil accumulated in the wheel mounting cylinder 19 can be discharged to the outside through the drain hole 55.

  57 is a sealing device that seals the space between the cylindrical spindle 15 and the wheel mounting cylinder 19 in a liquid-tight manner. The sealing device 57 is configured by using a so-called floating seal as shown in FIG. The rotating side retainer 59 is provided. The sealing device 57 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 the retainers 58 and 59, and earth and sand, rainwater, etc. Intrusion into the annular space C is prevented.

  Here, in the sealing device 57, the fixed-side retainer 58 is fixed in a clamped state between the motor housing cylinder 14 of the axle housing 12 and the cylindrical spindle 15 via a bolt 16 or the like as shown in FIG. . Further, the rotation side retainer 59 is fitted in the retainer mounting portion 19E of the wheel mounting cylinder 19, and is mounted to the end surface on one side in the axial direction via a bolt 60 or the like.

  Reference numeral 61 denotes a lubricating oil discharge portion serving as a lubricating oil discharge means for sucking and discharging the lubricating oil 100 in the wheel mounting cylinder 19 to the outside. The lubricating oil discharge portion 61 is connected to the above-described retainer 58 on the fixed side with a discharge pipe 61A. Are connected and provided. Here, the lubricating oil discharge pipe 61 </ b> A is disposed at the lowermost position between the cylindrical spindle 15 and the wheel mounting cylinder 19.

  The discharge pipe 61A, for example, supplies the lubricating oil 100 supplied in the first and second reduction gear housing spaces A and B and the annular space C as described above and stored on the lower side to an on-vehicle lubricating oil pump or the like. Thus, the air is discharged while sucking in the direction indicated by the arrow D in FIG. The lubricating oil discharged from the discharge pipe 61A is supplied again to the reduction gear mechanism 25, 38 side after being cooled by removing foreign matter with a filter or the like.

  Further, a detector (not shown) for detecting the height of the lubricating oil 100 accommodated in the cylindrical spindle 15 is provided on the small diameter portion 14B side of the motor accommodating cylinder 14, for example. When the liquid level in the cylindrical spindle 15 becomes higher than a predetermined reference liquid level, the lubricating oil 100 in the cylindrical spindle 15 and the wheel mounting cylinder 19 is discharged to the outside through the drain hole 55 and the like. Is done. As a result, the lubricating oil 100 in the cylindrical spindle 15 has a liquid level height illustrated in FIGS. 4 and 6 (for example, the same as or slightly lower than the central axis of the planetary gear 28 and the support pin 29). Is set to a liquid level height).

  62 is another sealing device disposed at a position outside the wheel mounting cylinder 19 in the axial direction. The sealing device 62 is configured as a so-called floating seal, and as shown in FIGS. And a final stage (second stage) carrier 43 through a fixed retainer 62A and the like. This sealing device 62 is also configured in substantially the same manner as the sealing device 57 shown in FIG. 4 arranged on one side (inside) in the axial direction of the wheel mounting cylinder 19, and the lubricating oil in the second reduction gear housing space B 100 prevents the leakage of 100 from the disk holding cylinder 22 and the retainer 62A on the carrier 43 side, and prevents the entry of external earth and sand, rainwater, and the like.

  63 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 63 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 63 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 63. is there. FIG. 6 shows a state in which the rear wheel 7 and the wedge member 63 are removed from the outer peripheral side of the wheel mounting cylinder 19.

  Further, 64 is a hoisting cylinder for hoisting the vessel 3 of the dump truck 1 shown in FIG. 1, and the hoisting cylinder 64 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 undulation cylinder 64 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 65 denotes a hydraulic oil tank. The hydraulic oil tank 65 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 65 is supplied to and discharged from the hoisting cylinder 64 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 travel drive device 11 provided on the rear wheel 7 side of the dump truck 1 rotates the electric motor 17 (rotating shaft 18) by a plurality of reduction gear mechanisms 25 and 38, for example, a reduction ratio of about 30 to 40. And the rear wheel 7 which is the driving wheel of the vehicle 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.

  By the way, in the multi-stage reduction gear mechanisms 25 and 38 used for the traveling drive device 11 of the dump truck 1, the carriers 30 and 43 that rotatably support the planetary gears 28 and 41 are several by using means such as casting. It is molded as a heavy product that reaches 100 kg (kilogram).

  For this reason, if a reduction gear device of a type that rotates the carriers 30 and 43 is taken as an example, if the position of the center of gravity of the carriers 30 and 43 is slightly deviated from the center of rotation, the carrier 30 and 43 is greatly increased as the carriers 30 and 43 rotate. This will cause vibration. Further, the carriers 30 and 43 need to ensure sufficient rigidity for rotatably supporting the plurality of planetary gears 28 and 41. For this reason, the carriers 30 and 43 should be formed as a heavy weight. Is required.

  Therefore, in the present embodiment, the axle housing 12 provided on the rear wheel 7 side of the vehicle is provided with the left and right motor housing cylinders 14 and the left and right motor housing cylinders 14 positioned on the outside in the axial direction. A first reduction gear housing space A is formed inside the cylindrical spindle 15 and a first stage carrier 30 is fixedly provided in the cylindrical spindle 15. It is configured.

  As a result, the first-stage reduction gear mechanism 25 can be compactly accommodated in the cylindrical spindle 15 (first reduction gear accommodating space A) of the axle housing 12, and the rotation of the carrier 30 is restrained by the cylindrical spindle 15. be able to. The ring gear 27 can be rotated in the cylindrical spindle 15 by the rotation of the first stage planetary gear 28, and the reduced rotation from the ring gear 27 can be taken out to the gear coupling 34 side.

  For this reason, the first-stage reduction gear mechanism 25 can be configured to extract the reduced speed from the ring gear 27 without rotating the heavy carrier 30 as in the prior art, and the carrier 30 is manufactured. This eliminates the need for special management of the center of gravity.

  Thereby, workability | operativity and productivity at the time of manufacturing the carrier 30 can be improved. Further, it is not necessary to give special consideration to the load distribution of the plurality of support pins 29 and the planetary gears 28 assembled to the carrier 30, and the assembling workability of the reduction gear mechanism 25 can be greatly improved.

  Then, the carrier 30 formed as a heavy weight that secures sufficient rigidity to rotatably support the plurality of planetary gears 28 is attached to the non-rotating portion of the traveling drive device 11 (for example, the axle housing 12, cylindrical shape). It can be utilized as a strength member for the spindle 15), and the strength and rigidity of the entire apparatus can be increased. Thereby, the thickness etc. of the cylindrical spindle 15 can be made small and weight reduction can be achieved.

  The second reduction gear mechanism 38, which is the final stage, can also restrain the rotation of the carrier 43 by fixing the carrier 43 to the cylindrical spindle 15 with a bolt 44 or the like. From the ring gear 40 integrated with the mounting cylinder 19, it is possible to take out the rotation of the decelerated large torque.

  The final stage carrier 43 is fixed to the other side (opening end) in the axial direction of the cylindrical spindle 15 so that the final stage carrier 43 is used as a lid covering the opening end side of the cylindrical spindle 15. The carrier 43 can assemble the cylindrical spindle 15 as a covered cylindrical body having a sturdy structure. Further, the rotation of the carrier 43 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 carrier 43 at the final stage can also be used as a strength member for the cylindrical spindle 15 and the like, and the strength and rigidity of the entire apparatus can be increased. This also makes it possible to reduce the thickness of the cylindrical spindle 15 and reduce the overall weight of the apparatus.

  Further, according to the present embodiment, the first stage carrier 30 is provided in a non-rotating state in the cylindrical spindle 15 serving as a casing, and between the first stage ring gear 27 and the second stage sun gear 39. Is provided with a gear coupling 34 for transmitting rotation between them, and a locking plate 35 is fixed to the outer peripheral portion 34A of the gear coupling 34 by a bolt 36 or the like.

  Then, the male spline teeth 34B of the gear coupling 34 are engaged with the stepped portion 27C of the ring gear 27 by engaging the claw portion 35A of the engagement plate 35 with the engagement groove 27D of the ring gear 27 as shown in FIG. The male spline teeth 34B of the gear coupling 34 are held between the plate 35 and the female spline teeth 27B of the ring gear 27.

  Therefore, even when the ring gear 27 is elastically deformed so as to be twisted with respect to the male spline teeth 34B and the like of the gear coupling 34 by meshing with the planetary gear 28 (torque transmission), it is provided on the outer peripheral portion 34A of the gear coupling 34. The bolts 36 and the like are not directly affected by the elastic deformation of the ring gear 27, and for example, the bolts 36 can be prevented from being slackened.

  On the other hand, as in the comparative example shown in FIG. 10, when the locking plate 35 ′ is fixed to the end face side of the ring gear 27 ′ with the bolt 36 ′, the following problem is likely to occur. . That is, the ring gear 27 'illustrated in FIG. 10 is provided on the outer peripheral portion 34A' of the gear coupling 34 'because the planetary gear 28 meshes with the inner teeth 27A' and a large torque is applied due to the rotation transmission. The ring gear 27 'may be elastically deformed so as to be twisted with respect to the male spline teeth 34B'.

  When the ring gear 27 ′ repeats such elastic deformation, the influence directly affects the bolt 36 ′. Therefore, the bolt 36 ′ that fixes the locking plate 35 ′ to the end face side of the ring gear 27 ′ Each time the ring gear 27 'repeats elastic deformation, slack is likely to occur. If the bolt 36 'is loosened, the locking plate 35' is dropped together with the bolt 36 'in the worst case, causing collision and interference with other components, causing wear and damage. There is a risk of becoming.

  However, in the present embodiment, since the locking plate 35 is provided by being fixed to the outer peripheral portion 34A of the gear coupling 34 with a bolt 36 or the like, even if the ring gear 27 is elastically deformed, it is directly elastically deformed. The locking plate 35 can be continuously fastened (fixed) to the gear coupling 34 that is not to be tightened by the bolt 36. For this reason, it can suppress that the influence accompanying the elastic deformation of the ring gear 27 reaches directly the volt | bolt 36 by the side of the gear coupling 34, and the slack of the volt | bolt 36 can be prevented over a long period of time.

  Therefore, according to the present embodiment, the gear coupling 34 provided between the ring gear 27 and the sun gear 39 at the next stage can be held in a state of being secured against the ring gear 27 for a long period of time. It is possible to suppress loosening and the like, and it is possible to improve the reliability and safety of the planetary gear reduction device (traveling drive device 11).

  Moreover, according to the present embodiment, the workability and productivity in manufacturing the carriers 30 and 43 of the reduction gear mechanisms 25 and 38 can be improved, and the work when the reduction gear mechanisms 25 and 38 are assembled. Can be improved. Further, since the first-stage reduction gear mechanism 25 can be housed 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 reduced in size and weight. Can also be achieved.

  Next, FIG. 11 shows a second embodiment of the present invention. In this 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. Shall.

  However, the present embodiment is characterized in that a wire 71 as a locking member is wound around a plurality of bolts 36, 36,.

  In this case, a small-diameter insertion hole (not shown) through which the wire 71 is inserted is formed on the head side of each bolt 36. Then, while the wires 71 are inserted into these insertion holes, the bolts 36, 36,... Are connected to each other with a wire 71 as shown in FIG. It is what is kept in the state.

Thus, such a constructed embodiment, Ki de be suppressed more reliably the loosening of the bolt 36 by a wire 71, it is possible to obtain substantially the same operational effects as the first embodiment.

  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 43 is fixed to the flange portion 15C of the cylindrical spindle 15 using the bolts 44 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 reduction gear device 24 is configured by the first-stage and second-stage reduction gear mechanisms 25 and 38 has been described as an example. However, the present invention is not limited to this, and may be applied to, for example, three or more planetary gear speed reducers.

  On the other hand, in the embodiment, the case where the locking plate 35 is fastened to the outer peripheral portion 34A of the gear coupling 34 with the three bolts 36 as shown in FIG. However, the present invention is not limited to this. For example, the locking plate may be fixed using one, two, or four or more bolts.

  Further, the holding member that holds the gear coupling against the ring gear in a retaining state is not limited to a flat locking plate, and may be a holding member having a block shape. Further, the screw portion of the bolt 36 may be loosened using an adhesive or the like.

  In the above embodiment, the case where the electric motor 17 is used as a rotation 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 the rotation 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, and may be applied to, for example, a front-wheel drive type or a four-wheel drive type dump truck that drives both front and rear wheels, and may be applied to a planetary gear reduction device other than the dump truck. It may be.

1 is an external view showing a dump truck on which a planetary gear reduction device according to a first embodiment of the present invention is mounted. 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 device, 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, reduction gear apparatus, etc. in FIG. It is sectional drawing which expands and shows the ring gear, planetary gear, gear coupling, etc. in FIG. It is a principal part enlarged view which shows the spline coupling part etc. of the ring gear and gear coupling in FIG. It is the side view which looked at a locking plate, a volt | bolt, etc. from the arrow IX-IX direction in FIG. It is sectional drawing in the same position as FIG. 7 which shows the latching plate and volt | bolt etc. by a comparative example. FIG. 10 is a side view at the same position as FIG. 9 showing a locking plate, bolts and the like according to the second embodiment.

Explanation of symbols

1 Dump truck 2 Car body 3 Vessel 5 Cabin 6 Front wheel 7 Rear wheel (wheel)
8 Engine 11 Traveling drive device 12 Axle housing 13 Suspension cylinder 14 Motor housing cylinder 15 Cylindrical spindle (casing)
17 Electric motor (rotation source)
18 Rotating shaft 19 Wheel mounting cylinder 20, 21 Bearing 22 Disc holding cylinder 23 Disc 24 Reduction gear device 25 First stage reduction gear mechanism 26, 39 Sun gear 27, 40 Ring gear 27D Locking groove 28, 41 Planetary gear 29, 42 Support pin 30, 43 Carrier 34 Gear coupling 34A Outer peripheral part 34B Male spline teeth (spline coupling part)
35 Locking plate (holding member)
35A Claw (tip side)
36 Bolt 71 Wire (Loosening member)
100 lubricating oil

Claims (3)

It consists of a cylindrical casing and a multi-stage reduction gear mechanism provided in the casing, and each stage of the reduction gear mechanism has a sun gear located on the center side thereof, and internal teeth are formed on the inner peripheral surface. In a planetary gear reduction device comprising a ring gear, a planetary gear meshing with the inner gear of the ring gear and the sun gear and transmitting the rotation of the sun gear to the ring gear, and a carrier that rotatably supports the planetary gear. ,
At least the first reduction gear mechanism among the reduction gear mechanisms is provided with the carrier in a non-rotating state in the casing, and transmits the rotation of the ring gear to the sun gear of the next stage and the next stage of the ring gear. It is configured to connect with the sun gear using a gear coupling,
In the gear coupling, a spline coupling portion that meshes with the inner peripheral side of the ring gear is formed,
A locking plate is provided between the gear coupling and the ring gear so that the tip side is locked to the inner peripheral side of the ring gear, and the spline coupling portion of the gear coupling is held in a retaining state with respect to the ring gear. ,
Locking plates, the planetary gear reduction device being characterized in that the you fixed configuration with a bolt on the gear coupling in locked state on the inner peripheral side of the ring gear. The ring gear of the first stage reduction gear mechanism has female spline teeth meshing with the gear coupling and a locking groove extending in the circumferential direction of the ring gear, and the spline coupling portion of the gear coupling is an external spline meshing with the internal spline of the ring gear, the distal end side of the locking plate, the planetary gear reduction according to claim 1 that have a claw portion for engaging the engaging groove of the ring gear apparatus. The gear coupling is configured by a circular plate-shaped annular body having an outer peripheral side splined to the ring gear and an inner circumferential side splined to the next-stage sun gear, and the locking plate is spaced on the outer circumferential side of the annular body. The planetary gear reduction device according to claim 1, wherein a plurality of the planetary gear reduction devices are provided.

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