JPS5941869Y2 - Agricultural tractor power transmission structure - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a power transmission structure for an agricultural tractor.

For more details, please refer to the power take-off shaft (PTO) for driving work equipment.
This relates to the power transmission structure to the shaft.

The objective is to obtain an independent power transmission structure to the PTO shaft that is not affected by the engagement or disconnection of the main clutch.

Three types of power transmission structures to the PTO shaft of conventional tractors have been considered.

The first is when there is only one clutch, and the PTO power is extracted from the power transmission system for driving power by branching it from near the transmission.

Second, the clutch at the rear of the engine flywheel is equipped with two clutches: a main clutch and a PTO clutch.
For dual clutch structure, when the drive shaft is also taken out as a double structure shaft.

The third case is when the PTO power is extracted by directly connecting the engine flywheel to the outside of the drive shaft of the traveling system.

Each has advantages and disadvantages; in the first case, when the running latch is disconnected, the PTO power transmission system is also disconnected.

Large tractors cannot be used for such tasks, such as root removal or digging, by moving the implement even when the tractor is stopped.

In the second case, a twin clutch device would be installed after the engine flywheel inside the clutch housing, which would increase costs and would place the running latch first on the side closest to the flywheel, and then on the rear side. Since the PTO clutch is installed so that it is in contact with the surface of the running latch, the PTO clutch will not rotate unless the running latch is engaged, so it is not suitable for the purpose of stopping the tractor and using the implement. not compatible.

In the third case, in order to eliminate the disadvantages of the first and second cases, a clutch for PTO power extraction was provided directly on the outer surface of the flywheel to extract rotational power without using a running latch. However, in this case, it is necessary to install a large PTO clutch with approximately the same diameter as the outside diameter of the flywheel and a small running latch that can fit inside the PTO clutch in a parent-child arrangement.
The drive shaft is outside and the traveling drive shaft penetrates inside, so it is necessary to provide another bypass PTO drive shaft for the PTO drive shaft before the traveling transmission section to bypass the traveling transmission section, and it is large. It had become a mission case.

In consideration of these points, the present invention has the PTO drive shaft penetrated into the drive shaft of the traveling system and directly connected to the flywheel of the engine.

The structure of the present invention will be explained based on the attached drawings showing the embodiments. Fig. 1 is an overall side view of the tractor.

A clutch housing 17 is fixed to the rear surface of the engine 16, and a transmission case 18 is connected to the rear surface of the clutch housing 17.

A PTO shaft 15 protrudes from the rear surface of the mission case 18 and drives the work machine.

FIG. 2 is a power transmission diagram of the power transmission structure of the present invention.

A PTO drive shaft 1 is directly connected to a flywheel 5 on the rear surface of an engine 16, and penetrates through the inside of the drive shaft 2.

The PTO drive shaft is connected to the next PTO countershaft 1 in the clutch housing 17 by the coupling 10.
a, and further connected to the PTO transmission shaft 1 via a coupling.
connected to c.

The power of the traveling drive shaft 2 is transmitted through a loosely fitted shaft on the PTO countershaft, and the speed is changed between the main transmission device B and the hydraulic clutch transmission shaft 19.

Thereafter, a sub-transmission device C is formed between the sub-transmission loose fitting shaft 20 on the PTO countershaft 2 and the final drive shaft 21, and drives the rear wheels via the differential device E.

The PTO drive shaft 1 is connected to a PTO counter shaft 1 a and a PTO speed change shaft 1 c, but all three shafts are placed on the same axis, and are only divided into three shafts for assembly and manufacturing purposes.

The PTO power passes through the three shafts mentioned above and reaches the PTO transmission B, where it is shifted into four gears and transmits rotation to the ηTO shaft 15.

FIG. 3 is a sectional view of the clutch housing 17.

In this embodiment, a front wheel drive device A is provided in the rear chamber of the clutch housing.

As the latch link 14 rotates, the bearing sleeve 6 slides on the outer circumference of the drive shaft,
The clutch bearing 7 pushes the clutch body 8 to disengage the clutch.

FIG. 4 is a sectional view of the engine flywheel section.

The front end of the coupling 3 with the flange 3c is tightly fitted into the spigot 25a of the crankshaft 25 to center the crankshaft and the coupling 3.

Since the coupling 3 is directly fitted to the spigot 25a of the crankshaft 25, no center runout occurs.

Similarly, since the spigot 5b of the flywheel 5 is closely fitted to the outer diameter portion of the crankshaft 25, the centering of the flywheel 5 can be performed without error.

The flywheel 5 is attached to the flywheel 5 with bolts 26.
It is fixed from the rear surface toward the end of the crankshaft 25.

Thereafter, the flange 3e of the coupling 3 is tightly fitted around the head of the bolt 26, and is fixed to the rear surface of the flywheel 5 with the bolt 3a.

FIG. 4 shows an embodiment in which the sliding body 9 of the bearing sleeve 6 is fixed to the outside of the running drive shaft.

4 is a friction plate of the moving latch.

Figure 5 shows the coupling 10.11 between the PTO drive shaft 1 and the traveling drive shaft just before the transmission case.
FIG. 3 is a cross-sectional view showing parts connected by.

13 is a pump for supplying pressure oil to the hydraulic clutch type transmission device.

These couplings 10, 11 simplify the assembly work.

As described above, in the present invention, the spigot part 5b of the flywheel 5 is fitted to the outer diameter part of the crankshaft 25 of the engine 16, the flywheel 5 is fixed to the crankshaft 25 from the rear with the bolt 26, and the bolt The outer diameter of the front end of the coupling 3 with the flange 3c, which is provided to avoid the head of 26, is
The PTO drive shaft 1 is fitted onto the inner diameter pilot part 25a of the crankshaft 25, and the flange 3c is fixed to the rear surface of the flywheel 5 with bolts 3a.
Since they are spline-fitted, the following effects are achieved.

First of all, since the coupling 3 is provided with the flange 3c, the flywheel 5 and the coupling 3 can be firmly fixed to each other. This eliminates the need for large-diameter splines.

Second, in the present invention, the power of the crankshaft is transmitted to the flywheel 5 through the bolt 26, and then from the flywheel 5 to the coupling through the bolt 3a. The power is transmitted through the coupling, and the spline length of the coupling is long, so it has sufficient durability.

Thirdly, centering is performed between the inlet part 25a and the crankshaft 25, and power transmission is performed between the flywheel 5, so centering accuracy is high and power transmission can withstand high loads. It was possible to make it into a device.

[Brief explanation of drawings]

Fig. 1 is an overall side view of the tractor, Fig. 2 is a power transmission diagram showing the power transmission structure of the present invention, Fig. 3 is a sectional view of the clutch housing section, Fig. 4 is a sectional view of the engine flywheel section, and Fig. 4 is a sectional view of the engine flywheel section. FIG. 5 is a sectional view of the coupling part. 1...PTO drive shaft, 2...
・Travel drive shaft, 3... Coupling, 5... Engine flywheel, 6...
...Bearing sleeve, 7...Clutch bearing.

Claims (1)

[Scope of utility model registration request] The spigot part 5b of the flywheel 5 is fitted onto the outer diameter of the crankshaft 25 of the engine 16, and the flywheel 5 is fixed to the crankshaft 25 from the rear with bolts 26, avoiding the head of the bolts 26. The outer diameter of the front end of the provided coupling 3 with the flange 3c is fitted into the inner diameter spigot part 25alC of the crankshaft 25, and the flange 3c is fixed to the rear surface of the flywheel 5 with bolts 3a. A tractor power transmission device characterized in that a PTO drive shaft 1 is spline-fitted.