JP3686789B2 - Bearing device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an improvement in a bearing device applied to a work vehicle such as a wheel loader.
[0002]
[Prior art]
Conventionally, as this type of bearing device, for example, the one shown in FIG. 7 is known.
The bearing device 50 includes a boss 51, a bush 52 fitted into the boss 51, a shaft 53 rotatably provided to the boss 51, and seals between the boss 51 and the shaft 53 provided on both sides of the bush 52. And a circumferential groove 55 cut in the inner periphery in the middle in the left-right direction of the bush 52, and a greasing hole 56 formed in the boss 51 and the bush 52 and communicating with the circumferential groove 55. ing.
Thus, in such a case, a lubricant such as grease is supplied from the greasing hole through the circumferential groove between the bush and the shaft, and lubrication is performed during this period.
[0003]
[Problems to be solved by the invention]
However, in such a case, when a deformable bush made of synthetic resin or the like is used, the lubricant turns to the outer peripheral side of the bush (between the boss and the bush) due to lubrication, and the lubricant Therefore, there was a risk that the bush would be deformed to the inner peripheral side and press the shaft. In addition, in order for the lubricant to be evenly supplied between the bush and the shaft, the position of the greasing hole is limited to the center (the middle in the left-right direction).
The present invention was devised to solve this problem in view of the above problems, and the problem is that there is no possibility of pressing the shaft even when using a deformable bush, An object of the present invention is to provide a bearing device in which the position of the greasing hole can be freely set.
[0004]
[Means for Solving the Problems]
The bearing device of the present invention basically includes a boss, a bush fitted into the boss, a shaft rotatably provided on the bush, and a seal provided between the boss and the shaft provided on both sides of the bush. Sealing, a notch formed on one side of the bush, a greasing hole formed in the boss and communicating with the notch, a chamfer formed in the bush and communicating the notch and the inner peripheral side of the bush, There is a feature in that it consists of.
[0005]
When a lubricant such as grease is supplied from the greasing hole, the lubricant is sent between the bush and the shaft through the notch and the chamfered portion, and lubrication between them is performed by the lubricant.
Since the bush is formed with a notch and a chamfered portion communicating with the greasing hole, the lubricant from the greasing hole is reliably guided to the inner peripheral side of the bush (between the bush and the shaft). Therefore, the lubricant does not enter the outer peripheral side of the bush (between the boss and the bush) and the bush is deformed, so that the shaft is not compressed and the rotation of the shaft is not hindered.
Since the notch and the chamfered portion are formed on one side of the bush, the greasing hole can be formed on one side of the boss along with this, and the position of the greasing hole can be freely set.
Since the notch and the chamfered portion are formed on one side of the bush, it can be easily formed as compared with the case where it is formed at the center, and the cost of the bush can be reduced.
[0006]
Preferably, the seal on the side adjacent to the notch is a double lip type dust seal, and the seal on the opposite side is a single lip type dust seal. In this way, the lubricant does not leak from the seal on the side adjacent to the notch, and the lubricant can be spread over the entire area between the bush and the shaft.
[0007]
The seal on the side adjacent to the notch is preferably a combination of a single lip type dust seal and an oil seal, and the seal on the opposite side is preferably a single lip type dust seal. In this way, the lubricant does not leak from the seal on the side adjacent to the notch, and the lubricant can be spread over the entire area between the bush and the shaft.
[0008]
The bush is preferably made of synthetic resin. In this way, manufacture is easy and cost reduction can be achieved.
[0009]
A storage groove that extends in the axial direction and communicates with the chamfered portion is preferably formed on the inner peripheral surface of the bush. In this way, since the lubricant supplied from the greasing hole is stored in the storage groove, it is possible to perform continuous lubrication over a long period of time.
[0010]
It is preferable that a plurality of notches and chamfers are formed at predetermined intervals on the circumference. In this way, the lubricant from the greasing hole can be more reliably guided to the inner peripheral side of the bush.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a longitudinal sectional front view showing a main part of a bearing device according to a first example of the present invention. FIG. 2 is a longitudinal front view showing the bush. 3 is a side view of FIG. 2 showing only half.
[0012]
The bearing device 1 includes a boss 2, a bush 3, a shaft 4, a seal 5, a notch 6, a greasing hole 7, and a chamfered portion 8.
[0013]
The boss 2 forms a basic part of the bearing device 1. In this example, the boss 2 has a block shape and is provided with a boss hole 9 penetrating in the axial direction (left-right direction in FIG. 1). The boss hole 9 is composed of a bush accommodating cavity 10 formed in the center in the axial direction and seal accommodating cavities 12 formed on both sides of the bush accommodating cavity 12 via a partition wall 11. The left seal housing cavity 12 is closed on the side, and the right seal housing cavity 12 is open on the side.
[0014]
The bush 3 is inserted into the boss 2. In this example, the bush 3 is made of synthetic resin, has a cylindrical shape, has a bush hole 13 that penetrates in the axial direction, and is inserted into the bush housing cavity 10. . A storage groove 14 communicating with the chamfered portion 8 and extending in the axial direction is formed on the inner peripheral surface of the bush 3. The storage groove 14 is for storing the lubricant, has a substantially arc-shaped cross section, and is formed in a plurality (eight) at predetermined intervals (every 45 degrees) on the inner peripheral surface of the bush 3.
[0015]
The shaft 4 is rotatably provided on the bush 3. In this example, the shaft 4 has a cylindrical shape and is rotatably inserted into the bush hole 13.
[0016]
The seal 5 is provided on both sides of the bush 3 and seals between the boss 2 and the shaft 4. In this example, the seal 5 on the side adjacent to the notch 6 (the left side in FIG. 1) is omitted in cross section. A double lip type dust seal 15 having a S-shape is formed, and a seal 5 on the opposite side (right side in FIG. 1) is a single lip type dust seal 16 having a substantially F-shaped cross section.
[0017]
The notch 6 is formed on one side of the bush 3 and is formed on the left side of the bush 3 in this example. That is, a plurality of (eight) notches 6 having a substantially trapezoidal shape are formed at predetermined intervals (every 45 degrees) of the circumference on the left side of the bush 3, and between the adjacent notches 6. Are formed with a plurality of (eight) protrusions 17 having a substantially inverted trapezoidal shape, and accordingly, the left side of the bush 3 has a crown gear shape. The notch 6 is formed at the same angular position of the circumference as these so as to be continuous with the storage groove 14 via the chamfered portion 8.
[0018]
The greasing hole 7 is formed in the boss 2 and communicates with the notch 6. In this example, the greasing hole 7 is formed so as to reach the left portion of the bush housing cavity 10 from the left outer peripheral surface of the boss 2. One of the greasing hole 7 and the notch 6 is inserted into the bush accommodating cavity 10 by appropriately rotating the bush 3 around the shaft so as to communicate with each other.
[0019]
The chamfered portion 8 is formed in the bush 3 to communicate the notch 6 and the inner peripheral side of the bush 3. In this example, a predetermined angle is formed between the end surface of the notch 6 and the inner peripheral surface of the bush 3. It is formed by excision at (45 degrees). A chamfered portion 18 is also formed between the end surface of the protrusion 17 and the inner peripheral surface of the bush 3 by cutting at a predetermined angle (45 degrees).
[0020]
Next, the operation will be described based on such a configuration.
When a lubricant (not shown) such as grease is supplied from the greasing hole 7, the lubricant is sent between the bush 3 and the shaft 4 through the notch 6 and the chamfered portion 8, and also into the storage groove 14. The oil is stored and lubrication between the bush 3 and the shaft 4 is performed by these lubricants.
Since the bush 3 is formed with a notch 6 and a chamfered portion 8 communicating with the greasing hole 7, the lubricant from the greasing hole 7 is surely supplied to the inner peripheral side of the bush 3 (the bush 3 and the shaft 4. Between). Accordingly, the lubricant does not enter the outer peripheral side of the bush 3 (between the boss 2 and the bush 3) and the synthetic resin bush 3 is deformed, so that the shaft 4 is not compressed and the shaft 4 rotates. Will not be disturbed.
[0021]
Since the left seal 5 adjacent to the notch 6 is a double lip type dust seal 15 and the opposite seal 5 is a single lip type dust seal 16, the lubricant leaks from the double lip type dust seal 15. Thus, the lubricant can be spread over the entire area between the bush 3 and the shaft 4.
Since the notch 6 and the chamfered portion 8 are formed on the left side of the bush 3, the greasing hole 7 can be formed on the left side of the boss 2, and the position of the greasing hole 7 is a position other than the center. Can be set freely.
Since the notch 6 and the chamfered portion 8 are formed on the left side of the bush 3, it can be easily formed as compared with the case where it is formed in the center, and the cost of the bush 3 can be reduced.
[0022]
Next, a second example of the present invention will be described with reference to FIG.
In the second example, the inclined surface 19 is formed on the one side (left side) upper portion of the boss 2, and the greasing hole 7 is inclined (upper left oblique direction) so as to reach the inclined surface 19 from the left part of the bush housing cavity 10. The formed point is different from the first example, and the other points are the same as the first example. In this way, the greasing position can be positioned on the side of the boss 2.
[0023]
Next, a third example of the present invention will be described with reference to FIG.
In the third example, the greasing hole 7 is a so-called right-angled one comprising a vertical hole 20 extending upward from the left part of the bush housing cavity 10 and a horizontal hole 21 extending leftward from the upper end to the left side of the boss. The point is different from the first example, and the other points are the same as the first example. In this way, the greasing position can be positioned on the side of the boss 2.
[0024]
Next, a fourth example of the present invention will be described with reference to FIG.
In the fourth example, the seal 5 on the side (left side) adjacent to the notch 6 is replaced with a single lip type dust seal (showing a substantially cross-sectional shape in cross section) 22 and an oil seal (O-ring) provided on the inside thereof. 23 is different from the first example in that it is composed of 23, and the others are the same as in the first example. In this way, the same effect as the first example can be achieved.
[0025]
In the above example, the bush 3 is made of synthetic resin. However, the bush 3 is not limited to this and may be made of metal, for example.
[0026]
【The invention's effect】
As described above, according to the present invention, the following excellent effects can be obtained.
(1) Consists of a boss, bush, shaft, seal, notch, greasing hole, and chamfered portion, and in particular, a chamfer that forms a notch on one side of the bush and connects the notch and the inner peripheral side of the bush. The lubricant can be reliably supplied to the inner circumference of the bush, and there is no risk of pressing the shaft even if a bush that is easily deformed is used. Can be set freely.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional front view showing a main part of a bearing device according to a first example of the present invention.
FIG. 2 is a longitudinal front view showing a bush.
FIG. 3 is a side view of FIG. 2 showing only half.
FIG. 4 is a longitudinal sectional front view of a main part showing a bearing device according to a second example of the present invention.
FIG. 5 is a longitudinal sectional front view showing a main part of a bearing device according to a third example of the present invention.
FIG. 6 is a longitudinal sectional front view showing a main part of a bearing device according to a fourth example of the present invention.
FIG. 7 is a longitudinal sectional front view showing a conventional bearing device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1,50 ... Bearing apparatus, 2,51 ... Boss, 3,52 ... Bush, 4,53 ... Shaft, 5,54 ... Seal, 6 ... Notch, 7,56 ... Greasing hole, 8, 18 ... Chamfer , 9 ... boss hole, 10 ... bush accommodating cavity, 11 ... partition wall, 12 ... seal accommodating cavity, 13 ... bush hole, 14 ... storage groove, 15, 16, 22 ... dust seal, 17 ... projection, 19 ... inclined surface, 20 ... vertical hole, 21 ... horizontal hole, 23 ... oil seal, 56 ... circumferential groove.

Claims (1)

A boss, a bush fitted into the boss, a shaft rotatably provided on the bush, a seal provided on both sides of the bush to seal between the boss and the shaft, and formed on one side of the bush It consists of a notch, a greasing hole that is formed in the boss and communicates with the notch, and a chamfered portion that is formed in the bush and communicates the notch and the inner peripheral side of the bush. that reservoir grooves extending in the axial direction communicates with the chamfered portion is formed a bearing apparatus for a feature.

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