JPH02151527A - Transmission structure for agricultural tractor - Google Patents

Abstract

PURPOSE:To reduce the height of a transmission case to improve riding comfortableness by dividing the inside of the transmission case into three sections, and arranging each main and sub-gear transmission mechanism, etc., of travelling system and PTO system for external power separately on both right and left sides in each section. CONSTITUTION:The inside of a transmission case M directly connected to an engine is divided into three sections 7-9 in front and in rear directions. Each main and sub-gear transmission mechanism 10, 11 of travelling system and PTO system for external power is arranged in the front section 7. Each sub-gear transmission mechanism 12, 13 of travelling system and PTO system is arranged in the intermediate section 8. Further, an actuating transmission mechanism 14 for driving rear wheels and receiving final transmitted power is arranged in the rear section 9. Each main and sub-gear transmission mechanism 10, 12 in the front section 7 and intermediate section 8 is arranged on one side to the longitudinal axis of the transmission case M, and each main and sub-gear transmission mechanism 11, 13 is arranged on the other side to the longitudinal axis of the transmission case respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a transmission structure for an agricultural tractor.

[Conventional technology]

Conventionally, the transmission equipped with a gear transmission mechanism for the traveling system and a gear transmission mechanism for the external power system was the Utility Model 63-2.
As shown in Publication No. 6, the transmission shafts constituting each of the two types of gear transmission mechanisms are arranged vertically and in parallel in a short section in the front and rear, and the horizontal cross-sectional shape of the transmission case is was vertically long.

[Problem to be solved by the invention]

As in the prior art, when the transmission shafts constituting the gear transmission mechanism are arranged in vertical positions and in short sections in the front and rear,
The mission case has a vertically long shape with large vertical dimensions,
For strength, it maintains its shape from front to back.

In other words, this means that in agricultural tractors where the transmission case also serves as the body frame, the center area of the step board is largely raised upwards, and the step board is completely separated to the left and right, making the footwell narrow. This also means that the protruding parts can get in the way when getting on and off, making it difficult to put your foot down.

The present invention improves the above-mentioned disadvantages by configuring a transmission case with a low height in the vertical direction by rationally arranging a gear transmission mechanism of a traveling system gear transmission mechanism and an external power system gear transmission mechanism. With the goal.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a transmission structure for an agricultural tractor that includes a gear transmission mechanism for the traveling system and a PTO system gear transmission mechanism for external power. 3 in the direction
The front compartment is equipped with the main gear transmission mechanism for the driving system and the main gear transmission mechanism for the PTO system, and the middle compartment is equipped with the auxiliary gear transmission mechanism for the driving system and the auxiliary gear transmission mechanism for the PTO system. The rear section is equipped with a differential transmission mechanism for rear wheel drive that receives the final shifting power of the running system, and the front section and the intermediate section are equipped with a main and auxiliary gear shift mechanism of the running system. The mechanism is disposed on one side of the transmission case in the left-right direction, and the PTO-based main/sub gear transmission mechanism is placed on the other side of the transmission case in the left-right direction.

[For production]

According to the above configuration, the multi-speed transmission gears can be distributed in the front and rear directions, and each shaft in the transmission case can be arranged so as to be longer in the lateral direction. , can have a low vertical height.

〔Effect of the invention〕

Therefore, by reducing the vertical height of the transmission case compared to the conventional one, the number of stages of the transmission gears and the arrangement of the transmission gears are improved.
Because we were able to achieve this while satisfying the function of case strength,
While being economically superior, it is possible to reduce the height at which the center of the step board swells upwards, and by making the step board as flat as possible, the area on which the feet can be placed increases, improving livability. did it.

Additionally, since the bulge near the center of the step board has been reduced, the possibility of your foot getting caught when getting on or off the board has been reduced as much as possible.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

In FIG. 5, an agricultural tractor is shown. An engine (E) is arranged at the front of the tractor body, and a control section (1) is provided at the center, and the power of the engine (E) is transmitted to the rear wheels (2) and the PTO shaft. (3) The single clutch type transmission case (M) that transmits information to the engine (
E) is directly connected to the front and back.

The control section (1) includes a handle (4) and a control seat (5).
, and a step board (6) for boarding, and the mission case (M) is located below the step board (6) near the left and right center.

As shown in FIG. 1, the inside of the mission case (M) is divided into three compartments (7), (8), and (9) in the front and rear direction, and the front compartment (7) has a Travel system main gear transmission mechanism (10) and PTO system main gear transmission mechanism (11)
In addition, the intermediate section (8) is equipped with a traveling system auxiliary gear transmission mechanism (12) and a PTO system auxiliary gear transmission mechanism (12).
3), the rear compartment (9) is equipped with a rear wheel drive differential transmission mechanism (14) that receives the final shifting power of the driving system, and the front compartment (7) and the intermediate compartment The main and sub gear transmission mechanisms (10) and (12) of the driving system in (8) are placed on one side of the right side of the transmission case (M), and the main and sub gear transmission mechanisms (If) and (13) of the PTO system are placed on the right side of the transmission case (M). It is arranged so as to be located on the other side in the left and right direction.

As shown in FIG. 2, the front section (7) receives power from the engine (E), and also includes an input shaft (15) equipped with a clutch (C) that disconnects and disconnects the transmission of the power. It is driven by a shaft (15) and a counter shaft (16).
) and the main gear transmission mechanism (1) of the four-speed traveling system.
0), the counter shaft (16), and the main gear transmission mechanism (11), which is driven by the intermediate shaft (17) and is a two-speed PTO system.
The PTO counter shaft (18) constituting the
A reverse shaft (19) equipped with a back gear for reversing the rotation of the TO counter shaft (18) is installed inside.

As shown in FIG. 3, the intermediate section (8) includes the counter shaft (16), a sub-drive shaft (20) that receives power from the counter shaft (16), and a sub-drive shaft (20) that reverses rotation from the counter shaft (16). a back shaft (21) equipped with a back gear that transmits the information to the sub-drive shaft (20); an output shaft that, together with the sub-drive shaft (20), constitutes a second sub-gear transmission mechanism (12a) of a two-speed traveling system; (22), and the creep shaft (23) that constitutes the second side gear transmission mechanism (12b) of the two-speed traveling system with this output shaft (22), the PTO counter shaft (18), and the PTO counter shaft (18). A counter shaft (18) and a PTO shaft (24) constituting the auxiliary gear transmission mechanism (13) of a two-speed PTO system are installed inside.

the first, second and second side gear transmission mechanisms (12a); (
12b) are collectively referred to as a traveling system auxiliary gear transmission mechanism (12). (Figure 4 shows the sub-drive shaft (20), the output shaft (2)
2) shows the arrangement relationship of the creep shaft (23)) The rear section (9) receives power from the output shaft (22) and transmits driving force to the left and right rear wheels (2), (2). It is equipped with a differential transmission mechanism (14) that distributes the

The main and auxiliary gear transmission mechanisms (10) and (12) of the driving system in the front compartment (7) and the intermediate compartment (8) are placed on the right side of the mission case (M), and the main and auxiliary gear transmission mechanisms of the PTO system ( 11) and (13) are arranged side by side on the left side.

As shown in FIG. 6, the step board (6) just extends from the rear half of the front compartment (7) of the mission case (M).
The mission case (M) is located above the front half of the middle section (8).
Since the cross-sectional shape of the step board (6) is long in the horizontal direction and low in the vertical direction, the height of the bulge near the center of the step board (6) can be reduced.

[Another example]

As shown in Figure 7, the PTO system also has an independent clutch (
The present invention may be applied to a transmission provided with C1). In this case, a PTO intermediate shaft (25) is added to the front section (7), which exclusively transmits power from the input shaft (15) of a dual shaft structure to the PTO counter shaft (18).
Even when the drive system clutch (C) is disengaged,
PTO shaft (24) by PTO system clutch (C2)
The rotation can be controlled intermittently.

Also, the transmission case (M) of this other example
and the transmission case (M) of the above-mentioned embodiment.
A mold for the case may be used in common for both. In this case, if the arrangement of the respective axes in each case is set to be a common axis based on the least common denominator, the drilling process and its equipment can be shared, which is economical.

8 to 11 are cross-sectional views showing the shaft arrangement in each part.

Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of the drawing]

The drawings show an embodiment of the mission structure of an agricultural tractor according to the present invention, and FIG. 1 is a developed view, and FIG.
3 is a sectional view taken along the line ■-■ in FIG. 1, FIG. 4 is a sectional view taken along IV-IV in FIG. 1, FIG. 5 is a side view of the agricultural tractor, and FIG. 7 is a developed view showing another embodiment, and FIGS. 8, 9, 10, and 11 are sectional views taken along lines VI-VI, IX-IX, and X-X of FIG. 7, respectively. ,X
It is a sectional view taken along the line I-XI. (7)...Front compartment, (8)...Middle compartment, (9)...Rear compartment, (10), (1
1) Main gear transmission mechanism, (12), (13
)... Sub-gear transmission mechanism, (14)...
Differential transmission mechanism.

Claims (1)

[Claims] Transmission case (M) directly connected to the engine
The interior is divided into three compartments (7), (8), and (9) in the front-rear direction, and the front compartment (7) houses the main gear transmission mechanism (
10) and a PTO-based main gear transmission mechanism (11), and the intermediate section (8) is equipped with a traveling-system auxiliary gear transmission mechanism (12) and a PTO-based auxiliary gear transmission mechanism (13). A rear wheel drive differential transmission mechanism (14) is provided in the rear compartment (9) to receive the final transmission power of the driving system, and
The main and sub gear transmission mechanisms (10) and (12) of the driving system in the front section (7) and the intermediate section (8) are located on one side in the left and right direction of the transmission case (M), and the main and sub gear transmission mechanisms of the PTO system are located on one side in the left and right direction of the transmission case (M). A mission structure of an agricultural tractor in which auxiliary gear transmission mechanisms (11) and (13) are arranged on the other side in the left and right direction.