JP3287226B2 - Wheel drive with hub reducer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a wheel drive device with a hub reduction gear.

[0002]

2. Description of the Related Art In a vehicle such as a snowplow or a rescue work vehicle that requires a large driving force compared to the capacity of an engine, a speed reduction device is attached to a wheel hub on which wheels are mounted in order to achieve a large reduction ratio. A wheel drive device with a hub reduction gear is conventionally known, and as an example, a utility model publication No.
There is a wheel drive device disclosed in the specification of No. 47 and the accompanying drawings.

[0003] In the above-described proposed wheel drive device, the wheel drive shaft or axle shaft is rotatably accommodated between the outer periphery of a spindle member or an axle tube and the inner periphery of a wheel hub on which the wheel is mounted. A single bearing chamber is formed for accommodating an inner hub bearing in the vehicle width direction and an outer hub bearing outward in the vehicle width direction for rotatably supporting the hub with respect to the spindle member or the axle tube. A planetary reduction gear that reduces the power of the wheel drive shaft or the axle shaft and transmits the output to the wheel hub is housed in a hub cover mounted on the outer end of the wheel hub in the vehicle width direction.

On the other hand, in a vehicle equipped with a wheel drive device with a hub reducer, such as a snowplow, the air pressure of the wheel tires is increased when traveling on a good road, and the tire pressure is increased when traveling on a bad road such as a snowy road. It is preferable to reduce the air pressure in terms of running performance. For this reason, an air chamber communicating with the inside of the wheel tire is provided at an intermediate portion in the vehicle width direction between the outer hub bearing and the inner hub bearing of the bearing chamber, and the air chamber is provided. When the compressed air source is supplied with compressed air from the vehicle's compressed air source according to road conditions, the bearing chamber is separated from the outer bearing chamber and the inner hub bearing that house the outer hub bearing by an intermediate air chamber. The outer hub bearing in the outer bearing chamber is separated by the lubricating oil sealed in the hub cover because the inner hub bearing is separated from the inner bearing chamber. Although are lubricated, the lubricating oil is not supplied to the inner bearing chamber of the inner hub bearing,
The inner hub bearing must be lubricated with grease.

As described above, when the inner hub bearing is grease-lubricated, the grease deteriorates quickly under severe driving conditions, and the grease must be replaced frequently. For this purpose, the hub cover and the planetary gear type speed reducer are required. Since the device and the wheel hub must be disassembled and reassembled after grease replacement, there is a problem that a great deal of labor is required and maintenance costs are significantly increased. In addition, the above problem is caused not only in the case where the air chamber is provided in the middle portion of the bearing chamber in the vehicle width direction, but also in some other circumstances, the bearing chamber is separated into the outer bearing chamber and the inner bearing chamber. This also occurs in the case.

[0006]

SUMMARY OF THE INVENTION The present invention relates to a wheel drive device with a hub reducer as described above, which comprises an outer hub bearing and an inner hub bearing which rotatably support a wheel hub on the outer periphery of a spindle member or an axle tube. By providing an air chamber or the like for adjusting the tire air pressure in the bearing chamber to be accommodated, the outer bearing chamber for accommodating the outer hub bearing and the inner bearing chamber for accommodating the inner hub bearing are formed separately from each other. In this case, it is possible to supply lubricating oil for reduction gear lubrication to the inner bearing chamber, effectively solve the above-mentioned problems when grease-lubricating the inner hub bearing, Aims to ensure durability and reliability and to greatly reduce maintenance costs It is intended to.

[0007]

SUMMARY OF THE INVENTION To achieve the above object, the present invention provides a method for manufacturing a vehicle, comprising the steps of: providing an outer periphery of a spindle member rotatably housing a wheel drive shaft; A bearing chamber for accommodating an inner hub bearing and an outer hub bearing that rotatably supports the wheel hub with respect to a spindle member is formed, and a casing mounted on an outer end side in the vehicle width direction of the wheel hub has the above-mentioned structure. A reduction gear receiving chamber for transmitting the output of the wheel drive shaft to the wheel hub is housed therein, and a reduction gear housing chamber for storing the lubricating oil therein is formed, wherein the bearing chamber houses the outer hub bearing. An outer bearing chamber that communicates with the reduction gear accommodating chamber; and an inner hub bearing that is disposed inwardly in the vehicle width direction from the outer bearing chamber. And an inner bearing chamber for accommodating the gearing. Further, the reduction gear accommodating chamber is provided through a play or passage formed between the outer periphery of the wheel drive shaft and the inner periphery of the spindle member. And a first oil passage communicating with the inner bearing chamber is bored in the spindle member.

[0008] In the present invention, it is preferable that a second oil passage communicating the inner bearing chamber and the reduction gear accommodating chamber is provided in the wheel hub. One end of the axis is a tapered roller bearing arranged so as to be deviated radially inward from the other end, and the first oil passage is opened at the one end side of the bearing, and the second oil passage is connected to the bearing. It is desirable to be provided so as to open to the other end side.
Further, the opening of the second passage on the inner bearing chamber side is
It is preferable to be disposed radially inward of the opening on the side of the reduction gear housing chamber. Preferably, the inner bearing chamber and the outer bearing chamber are separated from each other by an air chamber through which compressed air for adjusting tire pressure of a wheel mounted on the wheel hub flows.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment in which the present invention is applied to a front wheel drive device for a front axle of a snowplow or the like will be specifically described below with reference to the accompanying drawings. In the sectional view of the main part of FIG. 1, reference numeral 10 denotes an axle shaft whose inner end in the vehicle width direction is connected to a side gear constituting an output member of a differential (not shown). Are connected to a known Barfield constant velocity joint 12 to form an input shaft of the equivalent velocity joint 12. The output shaft 14 of the Barfield constant velocity joint 12 is
Together with the axle shaft 10, it constitutes a wheel drive shaft of the front wheel 16, which is shown only partially in the figure.

The output shaft 14 of the constant velocity joint is a knuckle 1
Outer and inner bearings 2 on the spindle member 20 of FIG.
2a and 22b rotatably supported by the outer peripheral surface of the output shaft 14 and the output shaft 14 of the spindle member 20.
A hollow cylindrical play or passage 24 is formed between the hole and the inner peripheral surface of the hole. The knuckle 18 is supported by a trunnion socket 26 fixed to an outer end in the vehicle width direction of an axle housing (not shown), and can freely move around the center of a spherical portion 26 ′ of the trunnion socket 26. it can. Further, the front knuckle 18 is steered by being driven around a trunnion 28 protruding in line with the outer periphery of the trunnion socket spherical portion 26 '.

A wheel hub 34 is rotatably mounted outside the spindle member 20 of the knuckle 18 via an outer hub bearing 30 and an inner hub bearing 32, and protrudes radially outward of the wheel hub 34. The wheel disc 16 'of the front wheel 16 is mounted on the outer surface of the flange portion 34' in the vehicle width direction via a number of hub bolts (not shown), and a brake is provided on the inner surface of the flange portion 34 'in the vehicle width direction. A disk 36 (or a brake drum) is mounted. The outer hub bearing 30 and the inner hub bearing 32 are accommodated in outer and inner ends in a vehicle width direction of a bearing chamber 38 formed by an outer peripheral surface of the spindle member 20 and an inner peripheral surface of the wheel hub 34. .

A sun gear 40 is fixed to the outer end of the constant velocity joint output shaft 14 constituting the wheel drive shaft in the vehicle width direction, and a plurality of sun gears 40 (for example, 5
) Planetary gears 42. The planetary gear 42 includes a gear shaft 44 formed integrally with the gear and a planetary carrier 48 via a pair of bearings 46.
The planetary carrier 48 is rotatably supported by the
Is fixed to a flange portion 34 'of the wheel hub 34 by a plurality of bolts 52 on a hollow cylindrical hollow cylindrical planetary casing 50 mounted concentrically to the spindle member 20.

The plurality of planetary gears 42 mesh with internal teeth of an internal gear or ring gear 54 housed in the planetary casing 50, and the internal gear 54 is connected to the spindle member via a connecting flange 56. 20 is connected to the motor 20 so as not to rotate relatively. The connection flange 56 has engagement teeth 58 provided on the outer periphery thereof meshed with the internal teeth of the internal gear 54, and spline internal teeth 60 provided on the inner periphery are provided on the outer periphery of the spindle member 20. Cooperating spline external teeth 62
To be engaged.

A substantially disk-shaped cover 64 is mounted on the outer end surface of the planetary casing 50 in the vehicle width direction.
The planetary casing 50, the cover 64, and the outer surface of the wheel hub 34 define a planetary gear type reduction device including the sun gear 40, the planetary gear 42, the planetary carrier 48, and the internal gear 54. 66 are formed. The above cover 64
A detachable plug 68 is provided at a substantially central portion of the speed reducer housing chamber 66 by removing the plug 68.
A lubricating oil (oil) is sealed therein to a normal level indicated by a two-dot chain line AA in the figure. Further, a drain plug 70 for exchanging oil in the reduction gear accommodating chamber 66 is provided below the cover 64 as needed.

A pair of annular air seals 72 and 74 are disposed substantially at the center of the bearing chamber 38 in the vehicle width direction, and an annular air chamber 7 is provided between the air seals 72 and 74.
6 are defined. Therefore, the bearing chamber 38 houses the outer hub bearing 30 and is separated from the outer bearing chamber 78 communicating with the speed reducer housing chamber 66 inward in the vehicle width direction with the air chamber 76 interposed therebetween. The inner bearing chamber 80 in which the inner hub bearing 32 is housed is separated from each other, and the outer bearing chamber 78 and the inner bearing chamber 80 do not directly fluidly communicate with each other.

In the inner hub bearing 32, one end of the axial line of the rollers arranged in the circumferential direction, that is, the outer end in the vehicle width direction is radially inside the other end, that is, the inner end in the vehicle width direction. A first oil passage which connects the cylindrical member 20 with the cylindrical play or passage 24 on the outer periphery of the output shaft 14 and the one end side of the inner hub bearing 32. 82 are drilled. The wheel hub 34 is provided with a second oil passage 84 that communicates the other end of the inner hub bearing 32 with the reduction gear accommodating chamber 66.
Is provided so as to be inclined such that the opening on the side of the reduction gear housing chamber 66 from the opening on the other end side of the inner hub bearing 32 is located radially outward.

Further, the wheel hub 34 is provided with a first air passage 88 having one end communicating with the air chamber 76 and the other end communicating with a nipple 86 for taking out air. It is connected to a tire valve 90. On the other hand, as shown by a dotted line in FIG.
A second air passage 92 having one end communicating with the air chamber 76 is provided. The other end of the second air passage 92 is connected to a compressed air source 96 via a pressure regulating valve 94 provided at an appropriate position in the vehicle. ing. The pressure regulating valve 94 supplies compressed air having an appropriate pressure according to the road conditions on which the vehicle travels to the tires of the front wheels 16 via the second air passage 92, the air chamber 76, and the first air passage 88. A valve device that can be manually operated by an occupant.

Further, one end of the knuckle 18 and its spindle member 20 communicates with a cylindrical space or play space 24 formed on the outer periphery of the wheel drive shaft, that is, the constant velocity joint output shaft 14, and extends upward. An air breather passage 98 is provided, and the air breather passage 98 is preferably opened to the atmosphere at an arbitrary high-level position of the vehicle via a suitable air breather pipe (shown by a two-dot chain line in the figure). The air breather passage 98 is provided to cope with a pressure change in the reduction chamber accommodating chamber 66 based on a temperature change of the lubricating oil in the chamber during traveling.

During traveling of the vehicle, the axle shaft 10 is driven by the driving force of the engine, and the output shaft 14 of the constant velocity joint 12 of the Barfield, that is, the wheel drive shaft is driven. The sun gear 40 mounted on the output shaft 14 rotates, and the planetary gear 42 revolves while rotating, and the planetary gear 42 revolves to rotate the planetary carrier 4.
The wheel hub 34, and thus the front wheel 16, is decelerated via a planetary casing 50 fixed to the planetary carrier 8 by bolts 52 and bolts 52.

The sun gear 40 and the planetary gear 42
By the rotation of the planetary carrier 48, the lubricating oil (oil) sealed in the reduction gear housing chamber 66 is directly supplied to the outer hub bearing 30 in the front bearing chamber 78 communicating with the reduction gear housing chamber 66. As a result, the bearing is effectively lubricated. A part of the lubricating oil in the speed reducer housing chamber 66 is a hollow cylindrical play or passage between the outer peripheral surface of the wheel drive shaft or the constant velocity joint output shaft 14 and the inner peripheral surface of the spindle member 20. 24, the first oil passage 8
2 to the inner hub bearing 32 to effectively lubricate the bearing. The lubricating oil that has lubricated the inner hub bearing 32
It recirculates to the reduction gear accommodating chamber 66 via the oil passage 84.

Since the first oil passage 82 is open at one end of the roller axis of the inner hub bearing 32, that is, at the radially inner end of the inclined taper roller, the lubricating oil is smoothly distributed by the centrifugal force. After flowing into the row and performing lubrication, it flows into the second oil passage 84 that opens at the other end of the roller axis, that is, at the radially outer end. The opening of the second oil passage 84 on the side of the reduction gear housing chamber 66 is formed by the inner hub bearing 32.
The lubricating oil flows smoothly in the second oil passage 84 due to the centrifugal force based on the rotation of the wheel hub 34, so that the inner hub bearing 32 Is supplied with a sufficient amount of lubricating oil.

According to the above configuration, the air seals 72 and 74 are provided at substantially the center of the bearing chamber 38 in the vehicle width direction.
Is provided, the outer bearing chamber 78 and the inner bearing chamber 80 which are separated from each other are formed separately, and usually grease lubrication must be performed. Since the inner hub bearing 32 can be effectively lubricated by the lubricating oil contained in the reduction gear housing chamber 66, the planetary gear type reduction gear required for grease lubrication is disassembled and removed, and grease is replaced. Also, since a great deal of labor and work time such as reassembly can be omitted at all, there is an advantage that the maintenance cost can be greatly reduced, and the durability and reliability of the outer hub bearing 30 and the inner hub bearing 32 are improved. Can be improved. Further, since lubricating oil does not accumulate in the inner bearing chamber 80, there is an advantage that the lubricating oil can be prevented from leaking from an oil seal portion provided at an end inside the wheel hub.

The present invention can be applied not only to the above-described front wheel drive device but also to a rear wheel drive device in substantially the same manner. When applied to a rear wheel drive, the knuckle 18
Spindle member 20 corresponds to the axle tube of the rear axle housing. In the case of rear wheel drive,
The Barfield constant velocity joint 12 may be omitted. In this case, the sun gear 40 is mounted on the outer end of the axle shaft 10 in the vehicle width direction. Further, in the above-described embodiment, the outer bearing chamber 78 and the inner bearing chamber 80 which are separated from each other are formed by providing the air chamber 76 for adjusting the tire pressure in the bearing chamber 38. For the other purpose, the bearing chamber 38 is separated or separated into an outer bearing chamber 78 and an inner bearing chamber 80 by a member or space.
The same can be applied to the case where the device is provided inside.

[0024]

As described above, the wheel drive device with a hub reducer according to the present invention has an outer periphery of a spindle member rotatably housing a wheel drive shaft and an inner periphery of a wheel hub on which wheels are mounted. A bearing chamber for accommodating an inner hub bearing and an outer hub bearing rotatably supporting the wheel hub with respect to the spindle member, and a casing mounted on the outer end side of the wheel hub in the vehicle width direction. Wherein a reduction gear receiving chamber for transmitting the output of the wheel drive shaft to the wheel hub is housed and a reduction gear housing chamber for storing lubricating oil is formed therein, wherein the bearing chamber is provided with the outer hub bearing. And an outer bearing chamber communicating with the reduction gear housing chamber,
The outer bearing chamber is separated from the outer bearing chamber inward in the vehicle width direction and is separated into an inner bearing chamber that houses the inner hub bearing.The outer bearing chamber further includes an outer periphery of the wheel drive shaft and a spindle member. A first oil passage for communicating the speed reducer housing chamber with the inner bearing chamber via a play gap or a passage formed between the spindle member and the inner periphery; Compared with the usual configuration in which the inner hub bearing is grease-lubricated, there are advantages that the maintenance cost can be greatly reduced and the durability and reliability of the inner hub bearing can be improved.

[0025] The second oil passage communicating the said inner bearing chamber and the reducer housing chamber, if provided in the wheel hub, the lubricant of the speed reducer accommodating chamber, the storage chamber Since it is possible to circulate between the bearing and the inner hub bearing, there is an advantage that the bearing can be effectively lubricated. Furthermore, the inner hub bearing is
One end of a roller axis is a tapered roller bearing arranged so as to be deviated radially inward from the other end. The first oil passage is opened at the one end side of the bearing, and the second oil passage is connected to the bearing. If it is arranged so as to open to the other end side, the circulation of the lubricating oil can be promoted by using the centrifugal force. When the opening is disposed radially inward of the opening on the side of the reduction gear housing chamber, there is an advantage that the circulation of the lubricating oil can be more effectively promoted. Further, when the inner bearing chamber and the outer bearing chamber are separated from each other by an air chamber through which compressed air for adjusting tire pressure of a wheel mounted on the wheel hub flows, the tire pressure is adjusted according to road conditions. Is appropriately adjusted to improve running performance, and the maintenance of the wheel drive device is easy, and therefore, there is an advantage that the maintenance can be performed at low cost.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part showing a preferred embodiment of the present invention.

[Explanation of symbols]

10: axle shaft, 12: Barfield constant velocity joint, 14: output shaft (wheel drive shaft) of Barfield constant velocity joint, 16: front wheel, 18: knuckle, 20: spindle member, 30: outer hub bearing, 32 ... Inner hub bearing, 34 wheel hub, 36 brake disk, 38 bearing chamber, 40 sun gear, 42 planetary gear, 48 planetary carrier, 50
Planetary casing, 54 ... internal gear, 6
6 ... reduction gear storage chamber, 72 and 74 ... air seal, 76 ...
Air chamber, 78: outer bearing chamber, 80: inner bearing chamber, 82: first oil passage, 84: second oil passage.

Continuation of the front page (56) References JP-A-58-139850 (JP, A) JP-A-50-54031 (JP, A) JP-A-52-98870 (JP, A) JP-A-62-221918 (JP) JP-A-49-62852 (JP, A) JP-A 62-91795 (JP, U) JP-A 2-60618 (JP, U) JP-A 64-53645 (JP, U) 30-8657 (JP, B1) Jiko 4-3147 (JP, Y2) (58) Fields investigated (Int. Cl. ⁷ , DB name) B60K 17/00-17/08 B60B 35/00-35 / 18 F16H 57/00-57/04

Claims (1)

(57) [Claims] An inner hub for rotatably supporting a wheel drive shaft relative to a spindle member between an outer periphery of a spindle member rotatably accommodating a wheel drive shaft and an inner periphery of a wheel hub to which the wheel is mounted. A bearing chamber for accommodating a bearing and an outer hub bearing is formed, and a speed reducer for transmitting the output of the wheel drive shaft to the wheel hub is provided in a casing mounted on the outer end side of the wheel hub in the vehicle width direction. A bearing housing for accommodating and storing a lubricating oil therein, wherein the bearing chamber accommodates the outer hub bearing and communicates with the reduction gear housing chamber; It is arranged separately from the outer bearing chamber inward in the vehicle width direction and is separated from the inner bearing chamber that houses the inner hub bearing. Further, a first oil passage for communicating the speed reducer accommodating chamber with the inner bearing chamber via a play or passage formed between the outer periphery of the wheel drive shaft and the inner periphery of the spindle member. A wheel drive unit with a hub reduction gear, which is bored in the spindle member.