JPS5921054Y2 - Vehicle bevel gear case seal structure - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a sealing structure for a bevel gear case in a front driving axle of a vehicle such as a tractor.

Conventionally, the seal structure of the above-mentioned bevel gear case is such that it is extremely difficult to replace seal members such as oil seals, and requires replacement of large parts.

For example, the bevel gear case provided at both ends of the front axle case is separated from the first and second bevel gear cases disposed above and below, and the bevel pinion shaft is mounted vertically across both gear cases. The gear cases are connected via the pinion shaft so as to be relatively rotatable about the pinion shaft.

A sealing member such as an oil seal is fitted into the connecting portion of both gear cases to prevent mud and the like from entering through the connecting portion.

However, in the prior art, seal members were separately provided in both the first and second bevel gear cases, and each seal member provided a seal between the gear case and the pinion shaft.

Therefore, mud or the like could enter between the upper and lower seal members, damaging the seal member, and since the pinion shaft, which rotates at high speed, was in sliding contact with the seal member, the pinion shaft was likely to wear out.

The work of replacing the pinion shaft and the like required an extremely large amount of labor and time.

Therefore, the present invention was devised in view of the above problems, and the first bevel gear case does not have a seal between the pinion shaft rotating at high speed and the bevel gear case, and the first bevel gear case rotates only slightly when the handle is operated. By sealing between the bevel gear case and the second bevel gear case, it is possible to extend the life of the seal member, reduce the wear of the parts that come into sliding contact with the seal member, and obtain a perfect sealing effect. To provide a bevel gear case seal structure for a vehicle that allows repair and replacement work to be performed easily and quickly even if a part is damaged.

Therefore, its characteristic feature is that the first
A bevel gear case of a vehicle in which a bevel pinion shaft is vertically mounted over a bevel gear case and a second bevel gear case, and both bevel gear cases are connected to each other via the pinion shaft so as to be relatively rotatable around the same pinion axis. From the inner periphery of one end surface of the communication hole through which the pinion shaft of the first and second bevel gear cases is inserted,
A cylindrical protrusion protruding into the other communicating hole is provided, and a sealing member having lips that slide on both the outer circumferential surface of the protruding portion and the end surface, respectively, is provided on the inner circumferential surface of the other communicating hole facing the protruding portion. It is fitted in a removable manner.

The present invention will be explained below based on the illustrated embodiments.

FIGS. 1 and 2 show a first embodiment of the present invention, which shows a front driving axle of a vehicle such as a four-wheel drive tractor, and since it is substantially symmetrical with respect to a straight line 1, only the substantially right half is illustrated.

Reference numeral 1 denotes a differential chamber containing a differential device 2, to which rotational power is transmitted from a propeller shaft (not shown) in the direction of arrow A in the figure to a heave pinion shaft 3 and an inner end of this bevel pinion shaft 3. It consists of a differential case 6, etc., which has a pinion 4 connected to it, and a bevel gear 5 that meshes with the pinion 4 fixed to its outer circumference.As is well known, a bevel pinion 7 is rotatably pivoted to the differential case 6. Both ends of the pinion shaft 8 are fixed, and the bevel pinion 7 meshes with a tip side gear 10 fixed to the inner end of the tip yoke shaft 9.

11 is an outer cylinder main body forming the differential chamber 1.

The differential yoke shaft 9 extending in the left-right direction is inserted through a seal member 12 such as an oil seal, and an adjustment screw member 14 having a male threaded portion 13 on the outer peripheral surface is inserted into the female threaded portion 16 of the cap body 15. They are screwed together.

A sealing member 17 such as an O-ring is interposed between the cap body 15 and the adjustment screw member 14.

The cap body 15 is fixed to the left and right openings of the outer cylinder body 11 with bolts or the like, and a bearing 18 that rotatably supports the differential case 6 is attached to the inner peripheral edge of the cap body 15. It is fitted into the recess.

Therefore, when the adjusting screw member 14 is rotated with a tool, the male threaded portion 13 and the female threaded portion 16 are screwed forward and backward.
Move the outer part of the bearing 18 to the left and right to attach the bevel gear 5.
It is possible to adjust the backlash between the pinion 4 and the pinion 4.

Such a cap body 15 is also attached on the opposite side with respect to the straight line 1, and the teat chamber 1 is sealed, and oil for lubricating the teat device 2, the bearing 18, etc. is sealed therein.

Reference numeral 19 denotes a front axle cylinder portion in the shape of a tapered cylinder or the like, which is removably fixed to the left and right openings of the outer cylinder main body 11 forming the differential chamber 1 by means of fixing devices such as 20 or the like. , into which the differential yoke shaft 9 is inserted.

In this way, two support chambers 21 are formed independently on the left and right inside the front axle cylinder part 19, and the front axle cylinder part 19
shows a welded structure.

The support chamber 21 is not filled with lubricating oil.

22 is a flange member connected to the outer end of the cylindrical portion 19 forming the support chamber 21, and includes a recess 24 into which a bearing 23 is fitted to rotatably support the differential yoke shaft 9;
The support chamber 21 side of the recess 24 has a recess 26 into which a seal member 25 such as an oil seal is fitted.

Next, 27 is a first bevel gear case, which is fixed to the flange member 22 of the cylindrical portion 19 by means of a flange bolt connection means, etc., and a bevel pinion shaft 28 serving as a king pin is vertically attached to the first bevel gear case 27. It is inserted in the facing position and supported by upper and lower bearings 29 and 30.

A bevel pinion 31 is fixed to the pinion shaft 28,
It meshes with a pinion 32 fixed to the end of the differential yoke shaft 9.

In this way, the bevel pinion shaft 28 is inserted and the bevel pinion 31. The inside of the first bevel gear case 27 containing the pinion 32 and the like is a bevel gear chamber 33, and the inside of the bevel gear chamber 33 is sealed with lubricating oil.

That is, the seal member 25 and the lower sinil member 3
4 etc. to ensure that there is no external leakage.

Next, 35 is a second bevel gear case, and a bevel gear 36 is fixed to the lower end of the bevel pinion shaft 28.
The final reduction gear 38 includes a final reduction gear 38 consisting of a bevel gear 37 that meshes with the final reduction gear 38, and a front wheel knob shaft 39 is rotatably pivoted approximately horizontally.

Further, 40 is a front wheel disc fixed to the outer end flange of the hub axle 39.

The inside of this second case 35 and the first bevel gear case 2
The lubricating oil is freely communicated with the bevel gear chamber 33 of No. 7, but it can also be separated.

In this way, the front axle is divided into the differential chamber 1, a pair of left and right bevel gear chambers 33, and the support chamber 21, and the support chamber 21 is not filled with lubricating oil.
The shape of the front axle cylinder portion 19 forming the support chamber 21 may be a rectangular cylinder or any other shape.

As shown in FIG. 2, the upper and lower first and second bevel gear cases 27 have bevel pinion shafts 28 inserted therein.
In each of the communication holes 41 and 42 of 35, a seal member 34 such as an oil seal is fitted at the lower end position of one of the communication holes 41, and the inner circumference of the upper end surface 45 of the other communication hole 42 is fitted. The sealing member 34 enters the communication hole portions 41 on three sides.
A cylindrical protrusion 43 is provided that comes into sliding contact with the inner circumferential surface.

In the illustrated example, the protrusion 43 is a sleeve 43 that is separate from the second bevel gear case 35 and tightly fitted into the inner surface of the communication portion 42.
An O-ring 44 is attached to the fitting part between the sleeve 43 and the communication part 42 to form a seal, and
An annular end surface 45 is formed above the sleeve 43 and is flush with the upper end surface 45 of the communicating portion 42 .

A lip 46 that comes into sliding contact with this annular end surface 45 is provided around the lower end surface of the sealing member 34 .

Further, in the illustrated example, the lip 47 provided on the inner circumferential surface of the sealing member 34 and slidingly contacting the sleeve 43 is a multistage lip, but it is also free to form a simple cylindrical shape.

Note that 48 is a spring for resiliently biasing the multistage lip 47 in the inner diameter direction to improve sealing performance.

Further, 49 is a bearing for rotatably supporting the bevel pinion shaft 28 on the second bevel gear case 35,
In the illustrated example, the upper end of the bevel gear 36 is extended into a cylindrical shape,
The inner ring of the bearing 49 is tightly fitted into it.

Thus, the sleeve 43 is connected to the lip 46 of the sealing member 34.
．． Since the sliding contact portion with 47 is subject to wear and damage due to the infiltration of muddy water, etc., it is preferable that the material be made of wear-resistant steel or that it be heat-treated for wear resistance.

In this way, since the sleeve 43 is a small component, the second
The bevel gear case 35 can be easily replaced and repaired.

Note that, contrary to the above embodiment, it is also possible to fit the sleeve 43 on the first bevel gear case 27 side and the seal member 34 on the second bevel gear case 35, respectively.

As described above, in the first embodiment of the present invention, the communication hole 41.4 of the first bevel gear case 27 and the second bevel gear case 35 into which the bevel pinion shaft 28 is inserted in a vertical position
a sealing member 34 on one side of 2, and the sealing member 34 on the other side.
The sleeve 43 is replaceably fitted as a cylindrical protrusion that slides into contact with the gear case 27.35, and is sealed at the joint between the first and second bevel gear cases 27.35. Compared to a seal between the rotating pinion shaft 28, the relative rotation of the first and second gear cases 27°35 is small, so the seal member 34
The wear of the sleeve 43 is reduced, and the wear of the sleeve 43 is also reduced.

Furthermore, it is sufficient to provide only one seal member 34 at the connecting portion, and there is no need to separately provide the first and second gear cases 27, 35 as in the conventional case, so that the number of parts can be reduced.

Moreover, since the sealing member 34 is in sliding contact with the outer peripheral surface and end surface 45 of the sleeve 43, a perfect sealing effect can be obtained.

In addition, since the cylindrical protrusion is formed by a replaceable sleeve 43, the large second bevel gear case 35
The sleeve 43, which is a small component, can be replaced and repaired easily and quickly without replacing the pinion shaft 28, etc., and can be extremely effective when used in tractors, etc. used in adverse environments. It is something.

Furthermore, it has been extremely difficult to provide wear-resistant treatment for only the sliding contact portion of the second bevel gear 35 with the seal member 34, which is a large component, but in the seal structure of the present invention, only the sleeve 43 is made of high-grade material or It is easy to handle wear and tear,
This has the significant effect of extending the life of the seal portion, and furthermore, can significantly reduce repair costs.

What is shown in FIG. 3 is a second embodiment of the present invention, which differs from the first embodiment in that a cylindrical protrusion 43 is integrally provided on one bevel gear case 35.

The other configurations are substantially the same as those of the first embodiment.

Note that the present invention is not limited to the above embodiments.

According to the present invention, a seal member is interposed between the first bevel gear case and the second bevel gear case, and the structure is such that the connecting portion of both cases is sealed, so that wear is reduced compared to conventional seals in high-speed rotating parts. and the life of the seal member is extended.

In addition, since the inner circumferential surface and one end surface of the sealing member are in sliding contact with the same end surface as the outer circumferential surface of the protrusion, the intrusion of mud from the outside is prevented in two stages, and a perfect sealing effect is obtained. In addition, it is easy to replace, and has many practical effects.

[Brief explanation of the drawing]

The figures show embodiments of the present invention; FIG. 1 is a sectional view showing the first embodiment, FIG. 2 is an enlarged sectional view of the main part, and FIG. 3 is an enlarged sectional view of the main part of the second embodiment. be. 27...First bevel gear case, 28...
...Bevel pinion shaft, 34... Seal member,
35...Second bevel gear case, 41.42.
...Communication hole portion, 43...Protrusion portion, 45.
·····End face.

Claims (1)

[Scope of utility model registration request] A bevel pinion shaft 28 extends over the first bevel gear case 27 and the second bevel gear case 35 arranged above and below.
is mounted on the shaft in a vertical position, and both bevel gear cases 27.35 are connected to the pinion shaft 28 via the pinion shaft 28.
In a bevel gear case of a vehicle that is relatively rotatably connected around the center of the vehicle, the first and second bevel gear cases 27.
From the inner periphery of one end surface 45 of the communicating hole 41 or 42 through which the pinion shaft 28 of 35 is inserted, the other communicating hole 41 is inserted.
A cylindrical protrusion 43 is provided that protrudes into the protrusion 47, and a lip 47.
A bevel gear case seal structure for a vehicle, characterized in that a sealing member 34 having a diameter of 46 is removably fitted to the inner peripheral surface of the other communication hole 41 facing the protrusion 43.