JP2512805Y2 - Power transmission device for agricultural tractor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a power transmission in an agricultural tractor, in which only the speed reduction ratio of the power transmitted from the engine side to the traveling section via the main clutch can be easily changed. It relates to the device.

[Problems to be Solved by Conventional Techniques and Inventions] Conventionally, in agricultural tractors, according to various modes,
It is widely practiced to replace the wheels (tires) in the running part with those of standard diameter and those of large diameter, but when the running wheels are replaced with those of large diameter, the peripheral speed increases. Therefore, the traveling speed exceeds the proper state. Therefore, when large-diameter wheels are mounted, the gear ratio of the traveling unit transmission system is set so as not to exceed the prescribed traveling speed.

However, in the case where the reduction gear ratio of the traveling section transmission system is set so that the specified traveling speed is not exceeded when the large diameter wheel is mounted as described above, when the wheel of the standard diameter which is frequently used is used, Since a sufficient traveling speed cannot be obtained, traveling at an appropriate speed is hindered, and there is a problem that work efficiency is reduced.

Therefore, it has been proposed to replace the speed change gears so that the speed change ratio corresponds to the wheel diameter, but for that purpose, there is a problem that the transmission case must be disassembled and the workability is poor. There is.

[Means for Solving the Problems] The present invention has been made in view of the actual situation as described above, with the object of solving these problems, in which the main clutch is on the front side and the main clutch is interposed. Running section and PTO
A center that has a clutch housing with a power take-out mechanism built into the rear side to take out the power to the shaft, and a power transmission mechanism to transmit the power taken out from the power take-out mechanism to the traveling section and the PTO shaft, respectively. In an agricultural tractor that is detachably connected to the case in the front-rear direction, the speed change gears for the running part of the power takeoff mechanism and the running part of the PTO shaft are located behind the speed change gear for the PTO shaft, and It is characterized in that it is arranged rearward of the bearing position for the rear end of the speed change shaft where these speed change gears are provided, and is exposed from the rear opening of the clutch housing from which the center case has been removed.

Further, the present invention is configured as described above to facilitate replacement of the speed change gear corresponding to the wheel diameter.

[Embodiment] An embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an example of a power transmission device for an agricultural tractor. In FIG. 1, 1 is an engine, 2 is a clutch housing, 3 is a center case, and a main clutch 4 for connecting and disconnecting the power input from the engine 1 is built in the clutch housing 2. A power take-out mechanism 5 on the PTO shaft side and a power take-out mechanism 6 on the running part side for taking out power transmitted to the PTO shaft (power take-out shaft) side 14 and the running part side via the main clutch 4 are built-in. Here, the power take-off mechanism 5 on the PTO shaft side is configured to transmit power to the power take-off clutch 9 from the main clutch 2 to the pipe shaft 7 via the idle gear 8, and the power take-off mechanism 6 on the traveling section side is Reduction gears that mesh with each other from the center shaft 10
The power is taken out to the passive gear 13 through 11,12.

The center case 3 is removably connected to the rear end of the clutch housing 2 in the front-rear direction. A mechanism 15 and a power transmission mechanism 17 for transmitting power from the passive gear 13 in the clutch housing 2 to the traveling portion 16 are built in. That is, in the power transmission mechanisms 15 and 17, the front end of the center shaft 19 of the driver shaft 18 having a coaxial double structure is connected to the power take-off clutch 9, and the rear end side thereof is the power take-out transmission mechanism.
It is connected to the PTO shaft 14 via 20 and the driver shaft 18
The front end of the pipe shaft 21 is connected to the passive gear 13 in the clutch housing 2 and is arranged around the passive gear 13.
Power is transmitted to the final transmission device 26 of the traveling unit 16 via the forward / reverse traveling transmission mechanism 23, the auxiliary transmission mechanism 24, and the differential device 25. 27 is a rear wheel axle. In addition,
The front wheel shaft 28 may also be driven as shown.
29 is its transmission shaft, and 30 is a differential device.

FIG. 2 shows a specific example of the power transmission device configured as described above. As shown in this figure, the speed change gear 11 constituting the power take-out mechanism 6 on the traveling side is a center shaft 10
The transmission gear 11 is disposed at a position rearward of the bearing 2a for pivotally supporting the rear end of the center shaft 10 on the clutch housing 2, and is detachably mounted by a retaining ring 31. The center case 3 is set to be exposed from the rear opening of the clutch housing 2 with the center case 3 removed, and can be replaced with another one having a different reduction ratio. The speed change gear 7a provided on the pipe shaft 7 to form the power take-out mechanism 5 on the PTO shaft side is arranged at a position in front of the bearing 2a.

The clutch housing 2 and the center case 3 are connected by a plurality of bolts 32. Center case 3
Oil plug on the upper side of the mating part with the clutch housing 2
34 have been opened. 35 is a dipstick, and this dipstick 35
Thus, the height of the lubricating oil surface a in the center case 3 can be confirmed from the mouth of the oil filling plug 34. An example of an agricultural tractor is shown in FIG. 3, where 36 is a front wheel and 37 is a front wheel.
Is a rear wheel, 38 is a driver's seat, and 39 is a traveling steering wheel. As in the present embodiment, if the speed change gear 11 of the power take-out mechanism 6 on the traveling portion side is configured to be attachable / detachable also through the mouth of the oil filling plug 34 of the center case 3, the reduction ratio can be changed. At this time, it is not necessary to remove the center case 3 from the clutch housing 2 one by one, and the work becomes easier. In this case, it is natural that the opening diameter of the oil filling plug 24 needs to be larger than the outer diameter of the transmission gear 11. As shown in FIG. 4 and FIG. 5, the engaging portion 4 may be formed on the speed change gear 11, and the replacement hook 41 of the speed change gear 11 may be used to facilitate the replacement work from the oil filling plug 34. .

According to the power transmission device configured as described above, the reduction ratio of the power takeoff mechanism 6 of the traveling section can be changed by replacing the speed change gear 11 corresponding to the wheel diameter. In this case, the speed change gear 11 is arranged rearward of the rear bearing 2a of the center shaft 10 on which the speed change gear 11 is supported, and therefore, when replacing the speed change gear 11, it is necessary to remove the bearing 2a one by one. You can easily do it without any trouble.

[Advantages] In short, since the present invention is configured as described above, when the gear ratio of the traveling unit transmission system is changed in accordance with the change of the wheel diameter, the rear traveling provided in the clutch housing is performed. It suffices to change the speed change gear of the power take-out mechanism for parts, but this speed change gear is arranged behind the bearing that supports the rear end side of the speed change shaft on which the speed change gear is provided,
When the clutch housing is removed from the center case, it will be exposed from the rear opening of the clutch housing.As a result, the change gear can be changed without removing the bearings, and the change operation is easy. become.

[Brief description of drawings]

The drawings show an embodiment of the present invention. Fig. 1 is a structural view of a power transmission device for an agricultural tractor, Fig. 2 is a longitudinal side view of a part thereof, Fig. 3 is an overall side view of the agricultural tractor, and Fig. 4 Is a front view of the speed change gear and its replacement hook, and FIG. 5 is a perspective view of the replacement hook. 2 is a clutch housing, 2a is a bearing, 3 is a center case, 4 is a main clutch, 5 is a power take-out mechanism of a PTO shaft, 6
Is a power take-off mechanism on the traveling section side, 9 is a power take-off clutch, 11 is a speed change gear, 15 is a PTO shaft side transmission mechanism, 16 is a traveling section side power transmission mechanism, and 17 is a traveling section side power transmission mechanism. .

Claims (1)

(57) [Scope of utility model registration request] 1. A clutch housing having a main clutch on the front side and a power take-out mechanism for taking out power to the traveling section and the PTO shaft via the main clutch on the rear side, respectively.
The power taken out from the power take-off mechanism is used for the traveling section and the PT.
In an agricultural tractor that is detachably connected in the front-rear direction with a center case that has a power transmission mechanism for transmitting power to each O-axis, for the traveling part of the power take-out mechanism and the traveling part of the PTO shaft. The transmission gears are arranged behind the transmission gears for the PTO shaft and behind the rear end bearing position of the transmission shaft where these transmission gears are installed, and exposed from the rear opening of the clutch housing with the center case removed. A power transmission device for an agricultural tractor having the above-mentioned configuration.