JPS5926156Y2 - Shaft coupling lubrication device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a lubricating device for a rotary drive shaft of a tractor or the like.

In tractors and the like, long shafts are used at corners.

These long shafts may be composed of a single shaft, but since the mission case is assembled by being divided into several parts, a shaft joint is used in the middle for assembly reasons. The method of joining is to machine an outer diameter spline on both ends of the shafts to be connected, machine an inner diameter spline on the shaft coupling side, fit them together, and use pins or rings to control the movement of the shaft coupling. Often individualized.

However, due to high-speed rotation of the shaft, misalignment of the shaft centers between the two connected shafts, and poor lubrication with grease, friction always occurs between the shaft coupling and the splines of the joint shaft, and as a result of long-term operation, the shaft coupling The diameter of the spline became larger, and the vibration noise of the shaft joint became louder, leading to damage.

In order to eliminate this problem, it is necessary to eliminate misalignment of the shaft center, reduce rotation speed, and improve lubrication, but it is extremely difficult to completely eliminate misalignment of the shaft center, and due to the structure of the tractor, It is also impossible to reduce the number.

As a result, there was a need for a structure that would ensure more reliable lubrication with grease and that could withstand long-term use, and that would allow new grease to be injected if vibrations occurred in the shaft joint.

Disassembling the coupling shaft, taking out the shaft coupling, and replacing the grease with new grease involves disassembling the entire tractor, which is a major undertaking, so it is possible to just leave the old grease in place and inject it from the outside with a grease pump. method is optimal.

Taking these points into consideration, the present invention aims to provide a reliable lubrication system and facilitate the replacement of deteriorated grease when the shaft coupling is located outside the oil bath. be.

The purpose of the present invention is as described above, and the structure of the present invention will be explained based on the structure of the embodiment shown in the attached drawings.

FIG. 1 is an overall side view of the tractor.

The engine 19 is housed in the bonnet 20, and the engine 1
A front frame 21 is provided to protrude forward from the lower side of the frame 9.

A front wheel differential case is pivotally supported on a front frame 21 via a center pin, and a front wheel 17 is fixed to a yoke shaft extending left and right from the front wheel differential case.

A clutch housing 12 is fixed to the rear surface of an engine 19, and a transmission case 22 is fixed to the rear surface of the clutch housing 12.

The rear wheel 18 is supported by a rear axle housing fixed to the side surface of the transmission case 22.

Several shaft joints are used in such tractors, but the shaft joints that are not lubricated by an oil bath include the shaft joint between the clutch shaft and the main shaft in the clutch housing 12, and the front wheel drive system. front wheel drive shaft,
This is the shaft joint between the front wheel power take-off shaft, etc.

FIG. 2 is a sectional view showing the position of the shaft coupling within the clutch housing 12.

The clutch housing 12 is fixed to the rear surface of the engine 19, and the main clutch 1 is mounted on the flywheel surface of the engine.
6 transmits rotation to the clutch shaft 14 by contacting the clutch shaft 14.

The rotation of this clutch shaft continues as it is in the transmission case 22.
Since the power is transmitted to the inner main shaft and then to the PTO transmission, a single long shaft is sufficient, but during assembly, it is divided into parts such as the clutch housing, transmission case, and rear axle case. Since these parts are combined to form a chassis, the shafts are also divided into separate parts.

There is a connection section consisting of a shaft coupling 3 in the clutch housing just in front of the transmission case, and since the clutch housing is not sealed with lubricating oil, a lubricating device exclusively for the shaft coupling is required.

FIG. 3 is a side sectional view of the front wheel drive unit.

Since the rotation of the front wheel drive must be synchronized with the rotation of the rear wheel drive, the rotation speed that is changed inside the transmission case is sent back to the front wheels.

The front wheel drive transmission is suspended from the abdomen of the transmission case 22, and the front wheel power extraction shaft 10 uses gears to extract rotation to the outside of the transmission.

A long front wheel drive shaft 9 is connected to this front wheel power take-off shaft,
The front wheel drive shaft protrudes toward the front in parallel with the clutch housing, and transmits rotation to the front wheel differential shaft.

A shaft coupling is also used between the front wheel power take-off shaft 10 and the front wheel drive shaft 9.

However, the shaft joint in this case is not only used for assembly purposes, but also to absorb the swinging of the front wheel tough case and front wheel drive shaft 9 that occurs when the front wheel yoke shaft rotates left and right. This means that the possibility of misalignment is taken into account.

Since this shaft joint is also outside the oil bath, it is necessary to provide a dedicated lubrication device to protect the shaft joint.

7 is a front wheel pinion shaft, and 8 is a front wheel differential case.

Front wheel drive shaft 9 and front wheel pinion shaft 7 inside the front wheel tough case
An external shaft joint is also used in between to absorb the swinging of the front wheel yoke shaft due to unevenness on the road.

The two shaft joints provided before and after the front wheel drive shaft 9 are symmetrical, and the swinging of the front wheel yoke shaft is absorbed by the balls 13 located in the spline grooves.

Figures 4, 5, and 6 regarding the configuration of the shaft coupling lubrication device.
This will be explained using the configuration shown in the figure.

FIG. 4 is a side sectional view of the shaft coupling showing a state where no grease is injected.

FIG. 5 is a sectional view of the shaft joint into which grease is injected by a grease pump.

Conventional shaft couplings were also lubricated by sealing grease into the grease reservoirs 4a and 5a provided on the shafts 4 and 5 during assembly, but if the temperature was too high, the grease would melt and cause the spline grooves to become clogged. The problem was that the grease would be lost as it passed through, and if the temperature was low, the grease would not come out from the grease reservoir.

In the present invention, a seal 2 is provided between the outer diameter of the shaft coupling 3 and the spline outer diameter of the shaft by an elastic body to prevent grease from escaping.
It is intended that the grease will mainly stay in the spline groove.

FIG. 2 is a front view of the seal 2.

The seal 2 is provided with a convex portion 2b so as to be fixed to the outer diameter of the shaft joint 3, and the shaft joint 3 is also provided with a recess portion 3a to be fitted.

The other end of the seal 2 has a spline portion 2a to be fitted into a spline groove, and the spline portion 2a is made tighter to a diameter smaller than the diameters of the shafts 4 and 5.

However, when fresh grease is press-fitted by a grease pump, the tightness is necessary to force the deteriorated grease A out of the spline portion 2a of the seal 2.

Conventionally, the lateral movement of the shaft coupling 3 has been prevented by fitting a ring into the inner diameter of the shaft coupling, but in that case, the passage between the grease reservoirs 4a, 5a and the spline groove was blocked. Movement is prevented by press-fitting the pin 6 into the shaft joint.

Further, a grease nipple 1 is provided at a position rotated 90 degrees from the press-fit hole of the pin 6, so that grease can be easily press-fitted from the outside with a grease pump.

If the lubrication of the shaft joint becomes poor and you start to hear noise at the shaft joint, press in the grease with a grease pump. The deteriorated grease A remaining in the spline will be pushed by the new grease and the spline of seal 2 will be pushed out. It is pushed out from part 2a.

As described above, the present invention provides a spline part at the connecting part of the two shafts 4 and 5, interposes a shaft joint in the spline part of the shaft, and gradually creates a gap between the outer periphery of the shaft joint and the spline part of the shaft. A cylindrical elastic seal 2 having a small diameter is inserted, and the large diameter part of the seal 2 is provided with a convex part 2b that is fixed to the outer diameter of the shaft joint, and the small diameter part of the seal 2 is provided with a convex part 2b that fits into a spline groove. The spline part 2a is constructed to be as compact as possible, and the seal 2 always seals the gnose inside the shaft joint, and the spline part 2a is configured to open outward when press-fitting with a grease pump, which is different from conventional Utility Model Publication No. 36-21406 etc. It has the following effects compared to other lubricating devices.

First of all, seal 2 seals the constant flow of grease.
Since it has a cylindrical shape that gradually becomes smaller in diameter, it also serves as a grease reservoir, increasing the amount of grease filled.

Second, although the seal 2 normally serves to seal the grease, it also serves as an opening for the grease to escape by opening when the grease pump is press-filled.

In conventional techniques such as Utility Model Publication No. 36-21406, the seal 2 and the opening for filling the pump are provided separately.

Thirdly, the opening when filling the pump is not a part that fits on the outer periphery of the shaft joint, but a small diameter spline part 2a, so the contradictory role of opening and sealing is performed by the spline groove fitting part of the spline part 2a. This could be done using the elastic convex part of the seal.

If both ends of seal 2 are brought into close contact with the circumference, the degree of sealing of the seal will be approximately the same at both ends, and unless the pump pressure is quite high, old grease will come out. There is a possibility that grease may be forced out due to the high pressure when the joint opens, but since the small diameter spline part 2a of the seal 2 constitutes the part that fits into the spline groove, this spline groove fitting part may be pushed out to the outside. This is because it can be easily turned over and the old grease that has accumulated in the spline groove can be easily drained from here.

Moreover, when the press-fitting by the pump is stopped, the spline groove fitting portion gradually returns to its original state due to its elastic force, and the degree of airtightness as a seal returns to its original state.

This ensures that the new grease pushes out the old grease in the spline grooves.

During normal rotation, the seal completely seals out the grease.

[Brief explanation of the drawing]

Figure 1 is an overall side view of the tractor. FIG. 2 is a side sectional view of the clutch housing. FIG. 3 is a side sectional view of the front wheel drive device. FIG. 4 is a sectional view of the shaft joint. FIG. 5 is a cross-sectional view of the grease press-fitted state. FIG. 6 is a front view of the seal. A... Degraded grease, 1... Grease nipple, 2... Seal, 3... Shaft joint, 4, 5... Shaft to be coupled, 6... Pin.

Claims (1)

[Scope of utility model registration request] A spline part is provided at the connecting part of the two shafts 4 and 5, and a shaft joint is interposed in the spline part of the shaft, and a cylindrical part whose diameter gradually becomes smaller is inserted between the outer periphery of the shaft joint and the spline part of the shaft. An elastic seal 2 is interposed, and the large diameter part of the seal 2 is provided with a convex part 2b that is fixed to the outer diameter of the shaft coupling, and the small diameter part of the seal 2 is provided with a spline part 2a to fit into the spline groove. A lubrication device for a shaft joint, characterized in that the grease in the shaft joint is always sealed by a seal 2, and the groove fitting part of the spline part 2a opens outward when press-fitting by a grease pump. .