JPH0444924Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an oil supply/lubrication device for a front wheel drive device of a tractor.

(Prior Art) A front wheel drive system for a tractor includes a transmission case at both ends of a front axle case, a front wheel case that rotates around a king pin axis on the outside of the transmission case, and a transmission mechanism inside each case. Since the front wheels are driven through the transmission mechanism, it is necessary to apply lubricating oil to the transmission mechanism and grease to the rotating parts.

For this reason, conventionally the structures shown in FIGS. 4 and 5 have been adopted.

In the one shown in FIG. 4, a transmission case 3 having a bevel gear mechanism 2 is attached to the end of a front axle case 1, and a front wheel case 5 with a built-in reduction bevel gear 4 is provided on the outside of the transmission case 3. The upper support part 6 is rotatably supported on the protruding shaft 9 of a bearing holder 8 for the king pin shaft 7 via a bearing body 10, and is attached to the bearing body 1 through a grease nipple 11.
This makes it possible to achieve zero lubrication.

The one in Fig. 5 is basically the same as the one in Fig. 4, so common parts are indicated by common symbols, but the bearing holder 8 is of a cylindrical structure, and the oil is supplied while air is vented through the plug 12. It was designed to do so.

(Problem to be solved by the invention) In order to lubricate gear oil (lubricating oil) for the bevel gear mechanism 2 and bevel gear 4 in the conventional example shown in FIG. When removing the screwed oil plug and applying oil from the oil hole, press the transmission case 3 with the bearing retainer 8.
Since the upper end is closed, it is difficult to vent air and, therefore, it is difficult to lubricate smoothly and quickly.

On the other hand, in the conventional example shown in FIG.
It is possible to lubricate the gear oil smoothly and quickly by removing the holder and venting air from here, but since the protruding shaft 9 of the bearing holder 8 has a cylindrical structure, the pressure inside the transmission case 3 may rise due to heat etc. caused by operation. Then, bearing body 1
0, there is a risk of atmospheric lubrication and leakage from the bearing body 10, which requires a special seal structure and complicates the structure.

Therefore, the present invention allows for smooth and quick lubrication by removing air when applying gear oil into the transmission case, while also preventing the leakage of atmosphere due to the pressure increase inside the transmission case and preventing grease build-up to rotating parts. The purpose is to make it possible.

(Means for Solving the Problems) The technical means taken by the present invention to achieve the above-mentioned object are characterized in that a transmission case 22 is provided at the end of the front axle case 20 having a cylindrical structure; A king pin shaft 24 interlocked with the differential output shaft 21 inserted into the front axle case 20 is inserted into the transmission case 22, and the upper and lower ends of the shaft are connected to bearings 25, 2.
6, and a speed reduction mechanism rotatably supported around the axis of the kingpin shaft 24 and interlocked via the kingpin shaft 24, located outside the transmission case 22. Further, a bearing holder 35 for the upper end side bearing 25 of the kingpin shaft 24 is attached to the upper end of the transmission case 22, and the bearing holder 35 is provided with a front wheel case 28 that houses the kingpin shaft 29. 24, and the upper support part 33 of the front wheel case 28 is fitted onto the projecting shaft 37 via a bearing body 38, and the outer end surface of the projecting shaft 37 40 and the inner end surface 41 of the upper support part 33 are vertically opposed to each other to form the bearing body 38.
It has a lubrication passage 42 communicating with the shaft outer end surface 40 of the protruding shaft 37 and the upper support portion 33.
Holes 43 and 44 that are vertically penetrated through the inner end surface 41 of the transmission case 22 and communicate with the inside of the transmission case 22 are formed, and a seal plug 45 can be freely inserted and removed from the protruding shaft 37 side of the holes 43 and 44. The hole 44 on the upper support part 33 side has a threaded structure, and a plug 46 having a grease nipple 47 is removably screwed therein.
7 through the lubrication passage 42 to the bearing body 38, and the plug 46
The seal plug body 45 is prevented from coming off, and further,
The gear oil filling hole 48 is provided with a gear oil filling plug which is separate from the plug 46 and is detachably attached thereto.

(Function) The room temperature inside the transmission case 22 rises and the sprayed oil that tries to enter the bearing body 38 due to the atmosphere is sealed by the seal plug 45, and the inside of the transmission case 22 becomes high temperature and pressure rises, causing a seal. Even if the stopper body 45 tries to come off, the plug 46 prevents it from coming off.

When the bearing body 38 is filled with grease from the nipple 47 of the plug 46 using a grease gun, the bearing body 38 is filled with grease through the lubrication passage 42 .

To apply lubricating oil (gear oil) into the transmission case 22, loosen the plug 46 and remove it from the hole 44, remove the seal plug 45 from the hole 43, remove the plug provided in the oil filling hole 48, and remove the plug from the hole 44. 48, but in this case, smooth and quick lubrication is achieved while air is vented through both the holes 43 and 44.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

In FIG. 1, 20 is a front axle case;
It has a cylindrical structure, and the middle part of its shaft length is supported by the tractor front vehicle bearing stand via a center pin, and has a differential mechanism inside, and the differential output shaft 2
1 is interpolated into it.

Reference numeral 22 denotes a transmission case, which is fixed to the end of the front axle case 1 via flange bolt coupling means 23.

Reference numeral 24 denotes a kingpin shaft, which is inserted into the transmission case 22 and is oriented vertically with a kingpin angle, and is supported by a bearing 25 at the upper part and a bearing 26 at the lower part.

A bevel gear mechanism 27 is provided on the upper side of the kingpin shaft 24 and at the end of the differential output shaft 21, and the kingpin shaft 24 is rotatable around its axis, and a bevel pinion is provided on the lower end side of the kingpin shaft 24. It has 27A.

28 is a front wheel case, which is provided on the outside of the transmission case 22, and has a planetary gear type reduction mechanism 2 inside it.
9 is built-in, and the bevel gear 30 of the reduction mechanism 29
is engaged with the bevel pinion 27A.

Reference numeral 31 designates a front wheel hub shaft, which is supported by the front wheel case 28 via a bearing 32, and is an output shaft of the speed reduction mechanism 29.

33 is the upper support part, and the front wheel case 28
The front wheel case 28 is attached to the upper end side via a bolt 34, and when a steering arm (not shown) is provided on the support portion 33 to transmit steering force, the front wheel case 28 can be freely rotated around the axis of the kingpin shaft 24. ,
Here, the front wheels can be steered.

Reference numeral 35 denotes a bearing holder, which is attached to the upper part of the transmission case 22 via a bolt 36, and supports the bearing 25 by fitting into the case opening with a spigot.

The bearing retainer 35 has a hat-shaped protruding shaft 37, which is aligned with the axis of the kingpin shaft 24, and is connected to the protruding shaft 37 via a needle-shaped or bush-shaped bearing body 38. A cylindrical portion 39 of the upper support portion 33 is fitted over the sleeve.

The shaft outer end surface 40 of the protruding shaft 37 and the upper support portion 33
The inner end surface 41 of the cylindrical portion 39 corresponds vertically to the inner end surface 41 of the cylindrical portion 39 , and a small lubrication passage 42 is formed therein, and communicates with the bearing body 38 via this passage 42 .

A hole 43 is formed in the shaft outer end surface 40 on an extension of the axis of the kingpin shaft 24, and a threaded hole 44 whose hole center is aligned with the hole 43 is formed in the inner end surface 41 of the support part 33. There is.

Reference numeral 45 denotes a seal stopper, which is supported in and out of the hole 43 so as to be freely inserted and removed, and has a seal ring 46 on the outer periphery, and is prevented from falling by a ring protrusion 43A formed in the hole 43.

In addition, the seal plug body 45 is formed with a bolt screw hole 45A for extraction.

A plug 46 has a grease nipple 47 and is screwed into the hole 44, and the inner end (lower end) of the plug 46 connects the seal plug body 4.
No. 5 is prevented from coming off from the hole 43.

Reference numeral 48 denotes an oil supply hole, which is opened at the top of the front wheel case 28 and into which a plug is screwed.

Gear oil is fully injected into the front wheel case 28 through this oiling hole 48, and the level of gear oil is maintained at level 49 by injecting oil into the transmission case 22 from the lower side to a level of 49. .

That is, if the oil filling hole 48 is located below the breather hole 50, the front wheel case 28 cannot be filled with gear oil, and since there is air, the air bubbles enter the transmission case 22 when the speed reduction mechanism 29 is driven. , the oil level in the case 22 was lowered and the bevel gear mechanism 27 was insufficiently lubricated.
This is avoided by placing the oil supply hole 48 above the breather hole 50.

In addition, FIG. 3 shows a tractor 51,
52 is a front wheel, 53 is a rear wheel, the above-mentioned configuration is adopted to drive the front wheel 52, and the propulsion shaft 54
It is linked to the front wheel differential mechanism via.

(Effects of the invention) According to the invention, the plug 46 having the nipple 47 is screwed into the hole 44, and the sealing body 45 is inserted into the hole 43 communicating with the transmission case 22. When grease is replenished, it enters the bearing body 38 through the lubrication passage 42 and is lubricated there.

At this time, the grease is prevented from entering the transmission case 22 via the seal plug 45.

Furthermore, even if the pressure inside the transmission case 22 increases and the seal plug body 45 tries to come off, the plug 46 prevents this coming off, thereby reliably preventing atmospheric oil from reaching the passage 42. , the seal of the bearing body 38 only needs to take into account the amount of grease build-up, and the structure becomes simple.

The plug 46 and the sealing body 45 are connected to the holes 43 and 4.
4, the gear oil can be inserted into and removed from the transmission case 22 through the holes 43 and 44 from which both the plugs 46 and 45 have been removed, and the transmission case 22 can be vented with gear oil through the oil filling hole 48, which has a plug different from the plug 46. Therefore, gear oil can be supplied to the transmission case 22 smoothly and quickly.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of an embodiment of the present invention, Fig. 2 is an enlarged sectional view of the main parts, Fig. 3 is an external view of a tractor equipped with the invention, and Figs. 4 and 5 are sectional views of conventional examples. . 20...Front axle case, 21...Differential output shaft,
22...Transmission case, 24...King pin shaft, 2
8...Front wheel case, 33...Upper support part,
35... Bearing holder, 37... Protruding shaft, 38... Bearing body, 43, 44... Hole, 45... Seal plug body, 4
6...Plug.

Claims (1)

[Scope of claim for utility model registration] Transmission case 2 provided at the end of the front axle case 20
A kingpin shaft 24 is vertically inserted into the transmission case 2, and upper and lower bearings 25 and 26 are provided for rotatably supporting the kingpin shaft 24 around the shaft center. A front wheel case 28 that is rotatable and has a built-in gear transmission mechanism 29.
Further, a bearing holder 3 for the upper bearing 25 of the kingpin shaft 24 is provided on the upper part of the transmission case 22.
5, and the upper support part 33 of the front wheel case 28 is rotatably fitted on the protruding shaft 37 provided on the bearing holder 35 via the bearing body 38. The support portion 33 has holes 43, 4 that communicate the inside of the transmission case 22 and the atmosphere.
4, and a seal plug 45 is provided in the hole 43 of the protruding shaft 37 to prevent leakage of sprayed oil in the transmission case 22.
A lubrication passage 42 is provided in the hole 44 of the upper support portion 33 and communicates with the bearing body 38.
A plug 46 having a nipple 47 for applying grease through the transmission case 22 is removably screwed to the plug 46, and the plug 46 prevents the seal plug 45 from coming off. An oil supply/lubrication device for a tractor front wheel drive system, characterized in that the oil supply hole 48 has a plug.