JP4890000B2 - Axle device and work machine - Google Patents

Description

  The present invention relates to an axle device and a work machine.

  Conventionally, work machines including construction machines such as wheel loaders and dump trucks are known. Such a working machine is configured to be able to self-run by rotating a tire with a driving force generated from an installed engine or the like. A planetary transmission that is used for an axle of such a work machine and functions as an axle device is known (for example, see Patent Document 1).

  The planetary transmission described in Patent Document 1 includes an inner sun gear (sun gear) located on the outer periphery of a drive shaft, an outer gear ring (ring gear) having a central axis at the same position as the inner sun gear, and an inner sun gear. Planetary gears (planet gears) that interact with the gears and the outer gear ring are provided. Among these, the planetary gear is rotatably held by the planet carrier, and the planet carrier is connected to a hub that fixes the wheels. The outer gear ring is held in a static housing. In such a planetary transmission, when the drive shaft rotates and the inner sun gear rotates, the planetary gear revolves along the outer periphery of the inner sun gear while rotating. At this time, the planet carrier and the hub that support the planetary gear rotate, and the hub rotates the wheel.

In such a planetary transmission device described in Patent Document 1, a plate (plate) as a separate body is attached to the surface of the hub that faces the drive shaft. Thereby, even if the drive shaft moves in the axial direction and the drive shaft slides on the plate, the hub can be prevented from being damaged.
Similarly, there is a known hydraulic drive unit with a reduction gear that has a plate interposed between the output shaft and the lid portion of the cylindrical case and can prevent the lid portion from being damaged even if the output shaft slides. (For example, refer to Patent Document 2). This plate is provided on a carrier that holds the planet gear.

Special table 2001-500823 gazette Japanese Patent Laid-Open No. 4-140538

  However, in the planetary transmission described in Patent Document 1, the drive shaft directly contacts the plate attached to the hub. At this time, since there is a rotational difference between the rotation of the drive shaft and the rotation of the hub, there is a problem that the end of the drive shaft slides with respect to the plate and the end of the drive shaft wears out. is there. In such a case, it is necessary to replace the drive shaft. However, if the work machine is large, the drive shaft is also large, so that the replacement work becomes complicated and the repair cost including the cost of parts of the large drive shaft is required. There is a problem that increases.

  In the hydraulic drive device described in Patent Document 2, the plate interposed between the output shaft and the lid of the cylindrical case is provided on a carrier that holds the planet gear, and the rotation of the output shaft and the plate A rotation difference occurs between the rotation. For this reason, like the planetary gearbox described in Patent Document 1, the output shaft may slide and wear against the plate, and it is necessary to perform troublesome replacement work, and the repair cost is low. There is a problem of increasing.

  An object of the present invention is to provide an axle device that can easily replace worn parts and reduce repair costs, and a work machine including the axle device.

In order to achieve the above-described object, an axle device according to claim 1 of the present invention is an axle device, and a torque shaft that rotates about an axial direction, and the torque shaft and the rotation center are arranged to be the same. A sun gear that rotates integrally with the torque shaft, a ring gear that has a central axis at substantially the same position as the sun gear, and that is disposed outside the sun gear, meshes with the sun gear and the ring gear, and A planet gear that rotates along the outer periphery of the sun gear, and a rotation mechanism that is disposed to face the end surface of the torque shaft and rotates via the planet gear or the ring gear, and the end surface of the torque shaft and the rotation mechanism between the, fixed to the sun gear or the torque shaft, the same rotational speed as the torque shaft Torukusha Wherein the shaft-side protective member which rotates Doo integrally is provided.

  The axle device according to a second aspect of the present invention is the axle device according to the first aspect, wherein the shaft-side protection member covers an end surface of the torque shaft and has an area of a surface facing the rotation mechanism. It is formed in the plate shape larger than the area of the said end surface, It is characterized by the above-mentioned.

  The axle device according to a third aspect of the present invention is the axle device according to the first or second aspect, wherein the surface of the rotation mechanism that faces the shaft-side protection member is opposed to the rotation mechanism. A detachable rotation mechanism side protection member is provided.

  A work machine according to a fourth aspect of the present invention includes the axle device according to any one of the first to third aspects.

According to the axle device of the first aspect of the present invention, the shaft-side protection member provided between the torque shaft and the rotation mechanism rotates at the same speed as the torque shaft. According to this, since a rotation difference does not arise between a torque shaft and a shaft side protection member, even when a torque shaft contacts the shaft side protection member, the wear of the torque shaft can be suppressed. Further, when the torque shaft moves to the side close to the rotation mechanism and the shaft-side protection member comes into contact with the rotation mechanism, the shaft-side protection member slides due to a rotation difference between the shaft-side protection member and the rotation mechanism. In some cases, the worn shaft side protection member may be replaced. Accordingly, since it is not necessary to replace a large torque shaft, the repair work can be easily performed and the repair cost can be reduced.
Furthermore, since the torque shaft and the shaft side protection member are separate bodies, the material selectivity of the shaft side protection member and the degree of freedom in processing can be improved. Therefore, the strength and surface roughness of the shaft side protection member can be adjusted, and wear of the shaft side protection member can be further suppressed.

  According to the axle device according to claim 2 of the present invention, the entire end surface of the torque shaft can be protected, and the sliding area of the shaft-side protection member with respect to the rotation mechanism can be increased. According to this, the surface pressure with respect to the rotation mechanism of the shaft side protection member can be reduced, and wear of the shaft side protection member can be suppressed.

  According to the axle device according to claim 3 of the present invention, when the shaft-side protection member moves in the direction approaching the rotation mechanism, the shaft-side protection member comes into contact with the rotation mechanism-side protection member. Wear of the rotating mechanism can be prevented. Further, when the rotation mechanism side protection member is worn, the rotation mechanism side protection member may be replaced, and the rotation mechanism can be omitted. Therefore, the repair work can be further simplified and the repair cost can be further reduced.

  According to the work machine according to claim 4 of the present invention, the same effect as the above-described axle device can be obtained, and maintenance of the work machine can be facilitated.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
(1) Schematic Configuration of Wheel Loader 1 FIG. 1 is a side view showing the wheel loader 1 according to this embodiment.
The wheel loader 1 is a work machine that transports and loads earth and sand obtained by excavation on a truck or the like. As shown in FIG. 1, the wheel loader 1 includes a vehicle body 2 having a front unit 21 and a rear unit 22.

Among these, the front unit 21 is connected to the rear unit 22 so as to be rotatable in the horizontal direction. The front unit 21 is provided with a container-like bucket 4 for excavating the earth and sand, transporting and loading the earth and sand, and a link mechanism 5 for moving the bucket 4.
Further, a cab 221 having a driver's seat therein is provided at a front center portion of the rear unit 22 and at substantially the center of the vehicle body 2.

  The front unit 21 and the rear unit 22 are provided with two tires 31 and 32 on the left and right, respectively, and each of the tires 31 and 32 is driven from an engine (not shown) mounted inside the rear unit 22. The vehicle body 2 is configured so as to be capable of self-propelled with power. The wheels 932 of the tires 31 and 32 are rotated by an axle device 6 described later.

(2) Configuration of Axle Device 6 FIG. 2 is a cross-sectional view showing the axle device 6 provided in the wheel loader 1. FIG. 3 is a partially enlarged view of FIG.
The axle device 6 is provided for each of the tires 31 and 32, and transmits the driving force of the engine to the tires 31 and 32 via a differential gear provided inside an axle housing (not shown).

As shown in FIGS. 2 and 3, the axle device 6 includes a torque shaft 7, a housing 8, and a rotation speed reduction mechanism 9 attached to the housing 8.
Among these, the torque shaft 7 is formed of a rod-like member having one end (the end on the arrow A1 side in FIGS. 2 and 3) connected to the differential gear, and is inserted through a housing body 81 of the housing 8 to be described later. (The end on the arrow A2 side in FIGS. 2 and 3) is exposed from the housing body 81.

(2-1) Configuration of Housing 8 The housing 8 holds the rotation speed reduction mechanism 9 rotatably. The housing 8 includes a housing body 81, a plate 82, a ring gear hub 83, two roller bearings 84 and 85, and a hydraulic piston 86.
The housing body 81 is fixed to the end of the axle housing of the vehicle body 2. The housing body 81 has a hole 811 through which the torque shaft 7 passes. Although not shown in detail, a brake disc 931 provided on a wheel hub 93 of the rotation reduction mechanism 9 described later is provided at the end of the housing body 81 on the side where the differential gear is arranged (arrow A1 side). A hydraulic piston 86 of a disc brake device that holds and stops the rotation of the wheel hub 93 is provided.

The plate 82 is attached to the end of the housing main body 81 on the opposite side (arrow A2 side) to the side where the differential gear is disposed. In the approximate center of the plate 82, the torque shaft 7 is inserted, and a hole 821 for positioning the torque shaft 7 is formed.
The ring gear hub 83 holds a first ring gear 912 and a second ring gear 922 of the rotation speed reduction mechanism 9 described later. The ring gear hub 83 does not allow the first ring gear 912 and the second ring gear 922 to rotate.
The roller bearings 84 and 85 are fixed to the outer periphery of the housing 8 and facilitate the rotation of the wheel hub 93 described later along the outer periphery of the housing 8.

(2-2) Configuration of Rotation Reduction Mechanism 9 The rotation reduction mechanism 9 transmits the rotation of the torque shaft 7 to the wheels 932 of the tires 31 and 32. The rotation speed reduction mechanism 9 includes a first rotation speed reduction mechanism 91, a second rotation speed reduction mechanism 92, and a wheel hub 93.
The first rotation speed reduction mechanism 91 decelerates the rotation of the torque shaft 7 and transmits it to the second rotation speed reduction mechanism 92. The first rotation speed reduction mechanism 91 includes a first sun gear 911, a first ring gear 912, a first planet gear 913, and a first carrier 914.

The first sun gear 911 corresponds to the sun gear of the present invention, and is splined to the end exposed from the housing body 81 of the torque shaft 7. Thereby, the torque shaft 7 and the 1st sun gear 911 rotate integrally.
The first sun gear 911 covers an end face of the torque shaft 7 on the tip side (arrow A2 side in FIGS. 2 and 3), and a thrust plate 9111 as a shaft-side protection member of the present invention is fixed in a replaceable manner. Yes. For this reason, the thrust plate 9111 rotates integrally with the torque shaft 7 and the first sun gear 911.

Here, since the torque shaft 7 is not fixed in the axial direction, it is conceivable that the torque shaft 7 moves in the axial direction (specifically, in the arrow A2 direction). On the other hand, since the thrust plate 9111 is provided on the first sun gear 911 so as to cover the end surface of the torque shaft 7, the thrust plate 9111 restricts the movement of the torque shaft 7 in the A2 direction.
In the present embodiment, the thrust plate 9111 is fixed to the first sun gear 911 by a pin as shown in the figure, but may be fixed by a screw.

The first ring gear 912 corresponds to the ring gear of the present invention, is an annular gear having internal teeth formed, and is arranged with the same rotation center as that of the torque shaft 7. The first ring gear 912 is fixed to the ring gear hub 83 described above.
The first planet gear 913 corresponds to the planet gear of the present invention, is disposed outside the first sun gear 911 and inside the first ring gear 912, and each of the first sun gear 911 and the first ring gear 912 Mesh. Since the first ring gear 912 is fixed to the ring gear hub 83, the first planet gear 913 revolves along the outer periphery of the first sun gear 911 while rotating by the rotation of the torque shaft 7 and the first sun gear 911. To do.

  The first carrier 914 holds the first planet gear 913 and rotates with the same rotation center as that of the torque shaft 7 as the first planet gear 913 revolves. The first carrier 914 includes a shaft member 9141 that supports the first planet gear 913, and a roller that is provided on the outer periphery of the shaft member 9141 and that smoothly rotates about the shaft member 9141 of the first planet gear 913. A bearing 9142 is provided. The first carrier 914 extends to the opposite side of the housing body 81 and is splined to the second sun gear 921 of the second rotation speed reduction mechanism 92.

The second rotation speed reduction mechanism 92 corresponds to the rotation mechanism of the present invention, decelerates the rotation transmitted from the first rotation speed reduction mechanism 91, and transmits it to a wheel hub 93 to be described later. The second rotation speed reducing mechanism 92 includes a second sun gear 921, a second ring gear 922, a second planet gear 923, a second carrier 924, and a cover 925.
The second sun gear 921 is arranged so that its center is located on the extension line of the rotation center of the torque shaft 7 and, as described above, the cylindrical gear spline-coupled with the first carrier 914 of the first rotation reduction mechanism 91. It is. For this reason, when the first carrier 914 rotates due to the rotation of the torque shaft 7, the second sun gear 921 rotates integrally with the first carrier 914. The second sun gear 921 is formed with a through hole 9211 that passes through the second sun gear 921 along the axial direction. A pedestal portion 9251 of a cover 925 described later is disposed in the through hole 9211. Is done.

  The second ring gear 922 is an annular gear fixed to the ring gear hub 83 and having internal teeth formed, similarly to the first ring gear 912 described above. The second ring gear 922 is disposed on the arrow A2 side so that the center is located on the extension line of the rotation center of the torque shaft 7 and is disposed outside the second sun gear 921.

  The second planet gear 923 is disposed along the outer periphery of the second sun gear 921 and inside the second ring gear 922. The second planet gear 923 meshes with the second sun gear 921 and the second ring gear 922, and revolves along the outer periphery of the second sun gear 921 while rotating as the second sun gear 921 rotates.

  The second carrier 924 is disposed so as to cover the first rotation speed reduction mechanism 91 and the second rotation speed reduction mechanism 92 of the rotation speed reduction mechanism 9, and is connected to the wheel hub 93 at the end on the arrow A1 side. The second carrier 924 is inserted into a hole formed substantially in the center of the second planet gear 923, and a shaft member 9241 that rotatably supports the second planet gear 923, the shaft member 9241, and the second planet gear. A roller bearing 9242 that is disposed between the second planet gears 923 and smoothes the rotation of the second planet gears 923 is provided. For this reason, the second carrier 924 rotates around the extension line of the rotation center of the torque shaft 7 with the revolution of the second planet gear 923.

  Further, a cover 925 is attached to the second carrier 924 so as to cover a range in which the second planet gear 923 revolves. A pedestal 9251 is fixed at a position facing the thrust plate 9111 on the inner surface of the cover 925 (the surface on the arrow A1 side).

Further, a washer receiving pedestal portion 9252 is fixed to the end portion of the pedestal portion 9251 on the arrow A1 side with a pin. A thrust receiving washer 9253 as a rotating mechanism side protection member of the present invention is attached to the surface of the washer receiving pedestal portion 9252 facing the thrust plate 9111 in a replaceable manner.
In this embodiment, the cover 925, the pedestal portion 9251, and the washer receiving pedestal portion 9252 are configured as separate members. However, the pedestal portion 9251 and the washer receiving pedestal portion 9252 may be provided integrally with the cover 925.

The wheel hub 93 is rotatably provided on the outer periphery of the housing 8 via roller bearings 84 and 85. A wheel 932 is fixed to the outside of the wheel hub 93 and the second carrier 924. For this reason, when the wheel hub 93 is rotated by the second carrier 924 of the second rotation speed reduction mechanism 92, the wheel 932 rotates integrally with the wheel hub 93.
A brake disc 931 is attached to the end of the wheel hub 93 on the arrow A1 side. The brake disc 931 is gripped by the hydraulic piston 86 provided in the housing 8, so that the rotation of the wheel hub 93 and thus the wheel 932 is stopped.

(3) Operation of Axle Device 6 Here, the rotation of the wheel 932 accompanying the rotation of the torque shaft 7 will be described.
When the torque shaft 7 rotates, the first sun gear 911 provided on the outer periphery of the torque shaft 7 rotates. The rotation of the first sun gear 911 is transmitted to the first planet gear 913 that meshes with the first sun gear 911. Here, since the first ring gear 912 meshing with the first planet gear 913 is fixed to the ring gear hub 83, the first planet gear 913 revolves while rotating along the outer periphery of the first sun gear 911. .

When the first planet gear 913 revolves, the first carrier 914 that holds the first planet gear 913 rotates around the extension line of the rotation center of the torque shaft 7. At this time, since the first carrier 914 is meshed with the second sun gear 921, the second sun gear 921 is rotated by the rotation of the first carrier 914.
The rotation of the second sun gear 921 is transmitted to the second planet gear 923 that meshes with the second sun gear 921. Since the second ring gear 922 meshed with the second planet gear 923 is fixed to the ring gear hub 83, the second planet gear 923 revolves while rotating along the outer periphery of the second sun gear 921.

  As the second planet gear 923 revolves, the second carrier 924 that supports the second planet gear 923 rotates. Since the second carrier 924 is connected to the wheel hub 93 at the end on the arrow A1 side, the wheel hub 93 rotates as the second carrier 924 rotates, and the wheel 932 fixed to the wheel hub 93 is used. Rotates.

According to such an axle device 6, the tip end surface of the torque shaft 7 facing the second carrier 924 can be protected, so that it is possible to prevent the torque shaft 7 from coming into contact with the second carrier 924 and directly passing each other. . Therefore, wear of the torque shaft 7 can be prevented.
In addition, since the thrust plate 9111 is formed of a separate member from the torque shaft 7 and the first sun gear 911, the degree of freedom in selecting the material and shape of the thrust plate 9111 can be improved. At this time, wear of the thrust plate 9111 can be suppressed by forming the thrust plate 9111 with a material having high strength. Further, by reducing the surface roughness of the thrust plate 9111 facing the thrust receiving washer 9253, the resistance of the thrust plate 9111 when the thrust plate 9111 slides in contact with the thrust receiving washer 9253 is reduced. Can do. Therefore, wear of the thrust plate 9111 itself can be suppressed by selecting the material of the thrust plate 9111 and adjusting the surface roughness.
Furthermore, since the thrust plate 9111 is provided so as to cover the end surface of the torque shaft 7, the entire front end surface of the torque shaft 7 can be protected.

Here, the area of the surface of the thrust plate 9111 facing the thrust receiving washer 9253 is formed to be larger than the area of the tip surface of the torque shaft 7. According to this, the surface pressure of the thrust plate 9111 with respect to the second carrier 924 can be reduced. Therefore, wear of the thrust plate 9111 can be further suppressed.
In addition, since the thrust plate 9111 is fixed to the first sun gear 911 in a replaceable manner, the thrust plate 9111 can be easily attached.

  When the torque shaft 7 moves in the direction approaching the second carrier 924, the thrust plate 9111 slides against the thrust receiving washer 9253. Since this thrust receiving washer 9253 is attached to the washer receiving pedestal 9252 in an exchangeable manner, when the thrust receiving washer 9253 is worn, the thrust receiving washer 9253 may be replaced. Accordingly, by providing the thrust plate 9111 and the thrust receiving washer 9253 that can be replaced when worn, it is not necessary to replace the entire torque shaft 7 and the second carrier 924, so that the repair work of the axle device 6 can be simplified. In addition, repair costs can be reduced.

(4) Modification of Embodiments The best configuration for carrying out the present invention has been disclosed above, but the present invention is not limited to this. That is, the invention has been illustrated and described primarily with respect to particular embodiments, but may be configured for the above-described embodiments without departing from the scope and spirit of the invention. Various modifications can be made by those skilled in the art in terms of materials, quantity, and other detailed configurations.
Therefore, the description limiting the shape, material, etc. disclosed above is an example for easy understanding of the present invention, and does not limit the present invention. The description by the name of the member which remove | excluded the limitation of one part or all of such is included in this invention.

  In the above embodiment, the axle device 6 including the first rotation speed reduction mechanism 91 and the second rotation speed reduction mechanism 92 has been described as the axle device, but the present invention is not limited to this. That is, the axle device may be configured such that the first carrier 914 of the first rotation speed reduction mechanism 91 is connected to the wheel hub 93 and the wheel hub 93 is rotated by the rotation of the first carrier 914. In such a case, a pedestal corresponding to the pedestal 9251 of the cover 925 may be provided on the first carrier 914, and a thrust receiving washer 9253 on which the thrust plate 9111 slides may be provided on the pedestal.

  In the above-described embodiment, the wheel hub 93 and the wheel 932 support the second planet gear 923 and are connected to the second carrier 924 that rotates by the revolution of the second planet gear 923. Not exclusively. That is, the second ring gear 922 rotates with the rotation of the second planet gear 923, the second carrier 924 is connected to the second ring gear 922, and the rotation of the second ring gear 922 causes the second carrier 924, The wheel hub 93 and the wheel 932 may be configured to rotate.

  In the embodiment, the first rotation speed reduction mechanism 91 and the second rotation speed reduction mechanism 92 are each configured to include one first planet gear 913 and second planet gear 923, but the planet gears included in the respective rotation speed reduction mechanisms. May be set as appropriate. That is, the first carrier 914 and the second carrier 924 may be configured to hold the planet gears provided in the first rotation speed reduction mechanism 91 and the second rotation speed reduction mechanism 92.

In the embodiment, the thrust plate 9111 is fixed to the first sun gear 911. However, the present invention is not limited to this, and the thrust plate 9111 may be fixed to the torque shaft 7.
Moreover, in the said embodiment, although the thrust plate 9111 is comprised as a plate-shaped body which covers the end surface of the torque shaft 7, this invention is not limited to this. That is, the thrust plate 9111 is disposed between the torque shaft 7 and the second carrier 924 so that the torque shaft 7 does not directly contact the second carrier 924 and a member that rotates integrally with the second carrier 924. It suffices if it is interposed between them.

  In the above-described embodiment, the wheel loader 1 is described as a work machine including the axle device 6, but the present invention is not limited thereto, and may be employed in a dump truck or the like. That is, the present invention can be adopted as long as the working machine has an axle.

  INDUSTRIAL APPLICABILITY The present invention can be suitably used for a working machine including a construction machine such as a wheel loader and a dump truck, particularly a working machine including an axle device that rotates a wheel.

The side view which shows the wheel loader which concerns on one Embodiment of this invention. Sectional drawing which shows the axle apparatus of the said embodiment. Sectional drawing which expands and shows a part of axle device of the said embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Wheel loader (work machine), 6 ... Axle apparatus, 7 ... Torque shaft, 92 ... 2nd rotation speed reduction mechanism (rotation mechanism), 911 ... 1st sun gear (sun gear), 912 ... 1st ring gear (ring gear) , 913... First planet gear (planet gear), 9111. Thrust plate (shaft side protection member), 9253... Thrust receiving washer (rotation mechanism side protection member).

Claims (4)

An axle device,
A torque shaft that rotates about the axial direction;
A sun gear that is arranged with the same rotational center as the torque shaft, and rotates integrally with the torque shaft;
A ring gear having a central axis at substantially the same position as the sun gear and disposed outside the sun gear;
A planet gear that meshes with the sun gear and the ring gear and rotates along the outer periphery of the sun gear;
A rotation mechanism disposed opposite to the end face of the torque shaft and rotating via the planet gear or the ring gear;
Between the end surface of the torque shaft and the rotation mechanism, a shaft-side protection member that is fixed to the sun gear or the torque shaft and rotates integrally with the torque shaft at the same rotational speed as the torque shaft is provided. Axle device characterized by. The axle device according to claim 1,
The axle device, wherein the shaft-side protection member covers an end surface of the torque shaft, and is formed in a plate shape in which an area of a surface facing the rotation mechanism is larger than an area of the end surface. The axle device according to claim 1 or 2,
An axle device characterized in that a rotation mechanism side protection member detachably attached to the rotation mechanism is provided on a surface of the rotation mechanism that faces the shaft side protection member. A work machine comprising the axle device according to any one of claims 1 to 3.

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