JP2582415Y2 - Drive axle device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive axle device used for a steering front wheel of a four-wheel drive tractor, for example.

[0002]

2. Description of the Related Art For example, in a small four-wheel drive tractor for a front wheel drive axle, a first gear case is fixed to an end of an axle case surrounding a differential yoke shaft, and a bevel gear is connected to the first gear case from the differential yoke shaft. And a second gear case supporting the lower portion of the king pin is attached to the first gear case so as to be rotatable around the king pin, and an axle flange is fixed to the second gear case. The second gear case and the axle flange support an axle to which power is transmitted from a kingpin via a bevel gear, and an upper portion of the second gear case is closed.

[0003]

In the above prior art, the second gear case is supported only by the lower half of the first gear case, and the upper portion is not supported, so that the supporting strength is low. Therefore, it is required that the upper part of the second gear case be supported by the first gear case like a large one.

However, the large front wheel drive axle device has a hole in the first gear case into which a kingpin is inserted from above, the upper bearing of the kingpin and the bevel gear are located above the differential yoke shaft, and the kingpin is located above the same. And a support member connected to the second gear case is fitted to the shaft member so as to protrude greatly above the axle case. The upper bevel gear acts as an obstacle, making it difficult to lubricate the bearings and to lubricate the shaft members.

According to the present invention, a bearing hole is formed in an upper portion of a first gear case of the small-sized device, and a shaft portion provided to project downward from a support body attached to a second gear case is inserted into the bearing hole. An object of the present invention is to provide a drive axle device capable of solving various problems.

[0006]

A specific means for solving the problem in the present invention is to fix a first gear case 4 to an end of an axle case 3 surrounding a differential yoke shaft 2, and
A king pin 7 to which power is transmitted from the differential yoke shaft 2 to the gear case 4 via the bevel gears 5 and 6 is connected to the differential yoke shaft 2.
More support below, the axis of the king pin 7 a second gear case 8 for supporting the bottom of kingpin 7 to the first gear case 4
Axle flange 9 is fixed to this second gear case 8 via two bearings 51 and 52 which are spaced apart from each other in the direction, and the bevel gear 10, An axle 12 to which power is transmitted via 11 is supported , a bearing hole 13 concentric with the kingpin 7 is formed in an upper part of the first gear case 4, and a support body 14 is detachably mounted on an upper part of the second gear case 8, A shaft portion 16 inserted into the bearing hole 13 via a bearing 15 is provided on the support body 14 so as to protrude downward.

[0007]

The second gear case 8 has an intermediate part in the first gear case 4.
Two bearings 5 spaced apart in the axial direction of the king pin 7 below
1 and 52 are rotatably supported at two points , and the upper part is on the upper part of the first gear case 4 via the support body 14.
The third point is supported . The support body 14 has a downwardly projecting shaft portion 16, is inserted through a bearing 15 into a bearing hole 13 formed in an upper portion of the first gear case 4, and projects too much upward from the first gear case 4. The bevel gear 5 of the differential yoke shaft 2 is located below the bearing 15, and the oil scattered by the rotation of the bevel gear 2 is
It is supposed to take.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. 1 and 2, reference numeral 1 denotes a drive axle device for a front steering wheel of a small four-wheel drive tractor. The differential yoke shaft 2 to which power is transmitted from the engine is surrounded by an axle case 3 pivotally supported on a front axle frame via a center pin.

A first gear case 4 is fixed to an outer end portion of the axle case 3, and a king pin 7 is fixed to the first gear case 4.
Is supported via bearings, and power is transmitted from the differential yoke shaft 2 to the king pin 7 via bevel gears 5 and 6. The king pin 7 is located below the differential yoke shaft 2, and the bevel gear 6 meshes below the bevel gear 5.

The lower half of the first gear case 4 is formed in a cylindrical shape, and two bearings spaced apart in the axial direction of the king pin 7.
A second gear case 8 is rotatably mounted around the king pin 7 via 51 and 52 . A bevel gear 10 is mounted below the king pin 7, and the lower part of the king pin 7 is supported by the second gear case 8 via the bevel gear 10 and a bearing.

An axle flange 9 is fixed to the second gear case 8, and an axle 12 is supported by the second gear case 8 and the axle flange 9 via a bearing. The axle 12 is provided with a bevel gear 11 that meshes with the bevel gear 10, and power is transmitted from the kingpin 7. A front wheel 18 is attached to the axle 12. The upper portion of the first gear case 4 was conventionally closed, but here, a cylindrical rising portion 19 is formed, and the kingpin 7 is formed on the inner periphery thereof.
The bearing hole 13 is formed concentrically with. On the other hand, a support body 14 is removably attached to the upper part of the second gear case 8 via bolts 20, and the support body 14 is provided with a shaft portion 16 protruding downward.

The shaft portion 16 is inserted into the bearing hole 13 through a bearing 15 such as a bush or a needle bearing, and is concentric with the bearings 51 and 52 and is separated upward.
To support the second gear case 8 with respect to the first gear case 4.
This is the third supporting portion . Since the bevel gear 6 is below the bevel gear 5, the bearing 15 and the shaft portion 16 are arranged close to above the bevel gear 5, and can supply lubricating oil scattered from the bevel gear 5.
No special lubricating oil supply means such as grease nipple is required. Reference numeral 21 denotes a seal member provided on the upper inner periphery of the rising portion 19.

FIG. 3 shows the structure of an axle case 3 made of sheet metal applicable to the drive axle device. The axle case 3 is divided into four parts in the axial direction. The central first case 30 in which the differential device 29 is housed is formed by welding a front and rear halved shape into a tubular shape, and front and rear center pin tubes 31 and 32 are protrudingly provided before and after the first case 30, and a rear center pin tube 32 is provided. , A bevel pin-on shaft 33 is inserted.

At both ends of the first case 30, fitting portions 34A and 34B whose diameters are enlarged are formed, and a second case 35 having a larger diameter is externally fitted and fixed to one of the fitting portions 34A.
A third case 36 and a fourth case 37 are internally fitted and fixed to the outer end of the case 35 and the other fitting portion 34B, respectively. The third case 36 and the fourth case 37 are formed to have the same diameter, and these and the second case 35 are formed of a cylindrical material.

As shown in FIG. 5, the conventional axle case 40 is divided into three in the axial direction, the second case 35 is not provided, and the inner end of the third case 36 is
Directly connected to The distance from the outer end of the third case 36 to the first case 30 is longer than the distance from the outer end of the fourth case 37 to the first case 30, and in the conventional axle case 40, the third case of the first case 30 The end on the 36 side receives a larger stress than the end on the fourth case 37 side, and thus there is a problem in the durability of the end. This problem can be solved by forming the first case 30 to be long and making the distance from the center pin to the left and right end portions the same.
No. 0 is for processing using a large press die, and changing the design of the press die undesirably increases costs.

Therefore, as shown in FIG.
Case 3 which can be formed of an inexpensive large-diameter cylindrical material by shortening
By providing 5, the inner end of the second case 35 is formed to have a large diameter even if a large stress acts on the same, so that the strength can be made sufficiently strong to withstand the stress. Become. In addition, the first case 30 can be used as it is.

[0017]

According to the present invention described in detail above, a bearing hole 13 concentric with the kingpin 7 is formed in the upper part of the first gear case 4, and a support body 14 is mounted on the upper part of the second gear case 8, and this support body Since a shaft portion 16 inserted into the bearing hole 13 via a bearing 15 is provided in a downwardly projecting shape at 14, and the shaft portion 16 is arranged at a position where oil from the bevel gear 5 of the differential yoke shaft 2 scatters, without significantly protruding the upper portion of the first gear case 4 and the second gear case 8 upwardly and cut in rotatably supporting the upper portion of the second gear case 8 on the first gear case 4.

The second gear case 8 has a first gear in the middle.
2 below the case 4 in the axial direction of the king pin 7
It is rotatably supported via the bearings 51 and 52 and
The upper portion of the first gear case 4 is
Because it is supported on the upper part, it increases the accuracy of machining the bearing hole
The three-point support with high support strength can be performed without
The support body 14 is attached to and detached from the upper part of the second gear case 8.
It is made possible by attaching it.

[Brief description of the drawings]

FIG. 1 is a sectional front view showing an embodiment of the present invention.

FIG. 2 is a view taken in the direction of the arrow X in FIG. 1;

FIG. 3 is a sectional plan view showing one example of an axle case.

FIG. 4 is a sectional view taken along line YY of FIG. 3;

FIG. 5 is a sectional plan view showing an example of an axle case.

[Explanation of symbols]

 Reference Signs List 1 drive axle device 2 differential yoke shaft 3 axle case 4 first gear case 5 bevel gear 6 bevel gear 7 kingpin 8 second gear case 9 axle flange 10 bevel gear 11 bevel gear 12 axle 13 bearing hole 14 support body 15 bearing 16 shaft portion

──────────────────────────────────────────────────続 き Continuation of the front page (56) References Japanese Utility Model Showa 57-103234 (JP, U) (58) Field surveyed (Int. Cl. ⁶ , DB name) B60K 17/30

Claims (1)

(57) [Scope of request for utility model registration] 1. A first gear case (4) is fixed to an end of an axle case (3) surrounding a differential yoke shaft (2), and a bevel gear (5) is connected to the first gear case (4) from the differential yoke shaft (2). A second gear case (8) supporting a king pin (7) to which power is transmitted via (6) below the differential yoke shaft (2) and supporting a lower portion of the king pin (7) in a first gear case (4). Separated in the axial direction of the king pin (7)
The second gear case (8) is attached rotatably via the two bearings (51, 52 ).
And the second gear case (8) and the axle flange (9) from the kingpin (7) to the bevel gear (10).
An axle (12) to which power is transmitted via (11) is supported , and a bearing hole (13) concentric with the kingpin (7) is formed in an upper portion of the first gear case (4), and a second gear case (8) is formed.
A support (14) is detachably attached to the upper part of the shaft, and a shaft (16) inserted into the bearing hole (13) via a bearing (15) is provided on the support (14) so as to protrude downward. A drive axle device characterized by the above-mentioned.