JPH02102827A - Speed change device of agricultural tractor - Google Patents

Abstract

PURPOSE:To install a speed change mechanism with ease by arranging a fuel tank on one side of a transmission case to lower the center of gravity of a tractor body and installing the speed change mechanism on the side of a fuel tank through the space between the transmission case and a seat from the other side of the transmission case. CONSTITUTION:In an agricultural tractor, an engine 4 is installed on the front of a tractor body 1 and is covered with a front cover 5 and a transmission case 15 is arranged on the rear. The upper rear of the body 1 is covered with a rear cover 15, on the upper surface of which a seat is installed. In this case, a fuel tank 31 is arranged on one side of a transmission case 11. Moreover, a speed change mechanism, not illustrated here, is installed on the side of a fuel tank 31 through the space between the top of the transmission case 11 and the bottom of a seat 17 from the other side of the transmission case 11. Speed change levers 41, 51 are arranged on the side of the seat 17 above the fuel tank 31.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a speed change operation device for an agricultural tractor.

[Prior art] In an agricultural tractor with a seat above a transmission case located at the rear of the vehicle body, a gear shift control lever was disposed on the side of the seat via a gear shift operating mechanism provided on the side of the transmission case. (For example, JP-A-Sho GO-45430
(Refer to Japanese Patent Publication No. 62-47740).

[Problems to be Solved by the Invention] By the way, when attempting to lower the center of gravity of a vehicle by arranging a fuel tank by utilizing the space on the side of the transmission case, it is necessary to place a gearshift on the side of the transmission case on the side of the fuel tank. It becomes difficult to provide an operating mechanism. The positions of the various shift control levers are determined. For example, if the main shift control lever is placed next to the seat on the right side of the vehicle, the auxiliary shift control lever and the PTO shift control lever are placed oppositely to the side of the seat on the left side of the vehicle. Therefore, the issue is how to configure the gear shift operation mechanism between the transmission case and the lever located on the side of the seat above the fuel tank.

Therefore, an object of the present invention is to lower the center of gravity of the vehicle body by disposing the fuel tank on one side of the transmission case, and to connect the gear shift operation lever located on the side of the seat above the fuel tank to the other side of the transmission case. It is an object of the present invention to provide a speed change operation device for an agricultural tractor in which a speed change operation mechanism can be easily constructed between the tractor.

[Means for Solving the Problems] In order to achieve the above-mentioned problems, the present invention provides an agricultural tractor in which a seat is arranged above a transmission case placed at the rear of the vehicle body, in which a fuel tank is arranged on one side of the transmission case. At the same time, a gear shift operation mechanism was installed on the fuel tank side from the other side of the transmission case through between the upper part of the transmission case and the lower part of the seat, and the gear change operation lever was installed on the side of the seat above the fuel tank. Features.

The upper surface of the fuel tank is formed with four parts through which the speed change operation mechanism passes, and the speed change operation lever consists of two levers, front and rear, with their lower fulcrums close to each other. A bent part is formed in the part.

[Function] First, by arranging the fuel tank on one side of the transmission case, the center of gravity of the vehicle body can be lowered.

In this way, fuel is passed from the other side of the mission case between the upper part of the mission case and the lower part of the seat to the gear shift operation lever, which is installed on the side of the seat above the fuel tank located on one side of the mission case. Since the speed change operation mechanism disposed on the tank side is connected, the speed change operation mechanism can be easily configured.

By forming a recess in the upper surface of the fuel tank, the speed change operation mechanism can be inserted into the recess.

In addition, if the shift operation lever is made up of two levers, front and rear, with the lower fulcrums close to each other, and a bent part is formed in the middle of both levers so that they intersect with each other in the operation range, the operation range of both levers will be approximately equal. Therefore, it is easy to operate.

[Example] Examples will be described below based on the accompanying drawings.

In FIGS. 1 and 2 showing the external appearance of an agricultural tractor embodying the present invention, a vehicle body 1 is provided with peg wheels 2 and rear wheels 3 on the front, rear, left and right sides, and an engine 4 is mounted on the front of the vehicle body 1. It is covered with a front cover 5, and front fenders 6 are integrally provided on the left and right sides thereof, 7 is a handle, and 8 is a floor. A mission case 11 is disposed at the rear of the vehicle body 1, a first propulsion shaft 9 from the engine 4 is connected within the upper part of the mission case front part 12, and a mission case rear part 13 is connected to the first propulsion shaft 9 from the engine 4.
A rear axle housing 14 is provided on the side.

The upper rear part of the vehicle body 1 is covered with a cover 15, rear fenders 16 are integrally provided on the left and right sides thereof, and a seat 17 is installed on the rear cover 15. Further, a second propulsion shaft 18 extending from the lower part of the front part 12 of the transmission case is connected to a front axle housing 19 disposed under the front of the vehicle body l.

As shown in FIGS. 3 and 4, a hydraulic cylinder 21 is installed approximately in the center of the rear part 13 of the transmission case, and a valve unit 22 is placed in front of it toward the right side of the vehicle body. The hydraulic cylinder 21 is provided with a pair of left and right working machine lift arms 23. A PTO (power takeoff) shaft 24 for driving the work machine is provided rearward from the rear part 13 of the mission case, and various operation pedals 25a, 25b, 25c for accelerator, brake, clutch, etc. are also provided as shown in FIG. There is.

Furthermore, a manual gear change operation lever 26 is provided on the left side of the vehicle body on the side of the seat 17, protruding from a control box 16L provided on the left rear fender 16, and a hydraulic clutch change operation lever 27 is provided on the right side of the vehicle body on the side of the seat 17. A working machine lifting/lowering operating lever 28 is provided protruding from a control box 16R provided on the right rear fender 16, and a 2WD/4WD switching operating lever 29 is provided protruding from the rear fender 16 in front of the control box 16R. Then, the sub-shift operation lever 41 and the P
A TO shift operation lever 51 is provided.

In the above agricultural tractors, mission case 11
A fuel tank 31 is arranged on the left side of the vehicle body on one side.

That is, as shown in FIGS. 3 and 4, the lower part 32 of the fuel tank 31 is located in front of the rear axle housing 14, the upper part 33 bulges above the transmission case 11, and the front part 34 is located in front of the transmission case front part 12. Extends to the sides,
Moreover, the rear portion 35 is shaped to extend above the rear axle housing 14. Further, the tank top surface 36 is substantially parallel to the bottom surface of the seat 17, and a relatively small four portion 37 is formed in the middle portion of the tank top surface 36.

In this way, the rear wheel 3 is attached to one side of the transmission case 11.
The center of gravity of the vehicle body is lowered by arranging a large-capacity fuel tank 31 by effectively utilizing the space between the two.

and on the side of the seat 17 above the fuel tank 31.

In other words, the auxiliary gear shift operation lever 41 and PTO on the left side of the vehicle body
The speed change operation lever 51 is connected to the right side of the transmission case 11 on the opposite side of the vehicle body in the following manner.

That is, as shown in FIG. 5, one end of a horizontal shaft 43 is connected to the lower part of the sub-shift operating lever 41, and the upper end of a rod 45 is pivotally connected to an arm 44 fixed to the other end of the horizontal shaft 43. , a link 46 is pivotally attached to the lower end of the rod 45, and the link 46 is attached to the rear part 13 of the mission case as shown in FIGS.
It is connected to a sub-shift operation shaft 47 that protrudes from the right side surface.

This constitutes the sub-shift operation mechanism 48.

Similarly, a rod 55 is pivotally connected to an arm 54 of a horizontal shaft 53 connected to the lower part of the PTO shift operating lever 51, and a link 56 pivoted to the rod 55 is connected to the PTO shift operating shaft on the right side of the rear part 13 of the transmission case. 57. This constitutes a PTO speed change operation mechanism 48.

The horizontal shaft 43 that forms the fulcrum of the sub-shift operation lever 41 is P
It is disposed adjacent to the rear of the horizontal shaft 53, which also serves as a fulcrum, of the TO shift operation lever 51, and both horizontal shafts 43, 53 are located above the rear part 13 of the transmission case, and above the hydraulic cylinder 21 and between the seat 17. It is placed between the lower part and the lower part. That is, both horizontal shafts 43.53 penetrate into pipes 49.59 of a bracket 50 shown in FIG. As shown in FIG. 3, it faces into a recess 37 in the upper surface 36 of the fuel tank.

In addition, as shown in an enlarged view in FIG.
The PTO and PTO shift operation levers 51 have bent portions 42.52 formed at their intermediate portions so as to intersect with each other in each operating range in the longitudinal direction in which they swing around their respective fulcrums 43.53.

That is, the sub-shift operation lever 41 is a cross type in which the upper part is located forward from the lower part via the bent part 42, and conversely, the PTO shift operating lever 51 is of a cross type with the upper part located forward from the lower part through the bent part 5.
It is of a cross type with the upper part located at the rear through 2. Further, the auxiliary shift operation lever 41 has a forward limit position indicated by a solid line in the figure as a third gear position (3), a rear limit position indicated by an imaginary line in the figure as a first gear position (1), and a second gear position (2) within that range. )
and neutral position (N), and likewise PT
The rear limit position of the O-shift operation lever 51 indicated by the solid line in the figure is PTO.
The 1st speed position 21 (1) of the shaft 24 gear shift, the forward limit position of the illustrated virtual line is the 3rd speed position (3), and the 2nd speed position (3) is within that range.
2) and neutral position 1! There is (N).

In this way, the sub-shift operating lever 41 and the PTO shift operating lever 51 have a cross-type shape that intersects with each other in the operating range, so that the stroke range of both levers 41.51 becomes - in a side view, and as shown in FIG. As shown by the arrows, the stroke ranges from the maximum distance from each other are small, so the grip positions of both levers 41 and 51 can be set closer compared to those that stroke in the front and rear directions that are far apart from each other. It has good operability.

Although not shown, the manual gear change operation lever 26 on the left side of the seat 17 is connected to the front part 12 of the transmission case.
It is connected to the manual gear change shaft on the left side.
Further, the hydraulic clutch change operation lever 27 and the work equipment lifting operation lever 28 on the right side of the seat 17 are connected to the hydraulic clutch change shaft on the right side of the transmission case front part 12 and the lift operation shaft on the right side of the valve unit 22 of the hydraulic cylinder 21. They are each connected.

As shown in FIG. 5, the 2WD/4WD switching operation lever 29 on the right side of the seat f is connected to a horizontal shaft 91 passing through the pipe of a bracket 90 that is bolted to the front part 12 of the transmission case. to rod 93
A link 94 is connected to a 2WD/4WD switching operation shaft 95 on the left side of the front portion 12 of the transmission case. Therefore, the horizontal shaft 91, which forms the fulcrum of the 2WD/4WD switching operation lever 29, is also disposed to pass between the upper part of the transmission case front part 12 and the lower part of the seat 17.

[Effects of the Invention] As described above, according to the present invention, in an agricultural tractor, since the fuel tank is disposed on one side of the transmission case, it is possible to contribute to lowering the center of gravity of the vehicle body. The gear shift operating lever located on the fuel tank side is connected from the other side of the transmission case through between the upper part of the transmission case and the lower part of the seat, so the gear shifting operating mechanism is Can be easily configured.

By forming a concave portion on the upper surface of the fuel tank, the speed change operation mechanism can be inserted through the concave portion.

In addition, if the shift operation lever is made up of two levers, front and rear, with the lower fulcrums close to each other, and a bent part is formed in the middle of both levers so that they intersect with each other in the operation range, the operation range of both levers will be approximately equal. Therefore, operability can be improved. Also, the front and rear operation range becomes narrower, and the length of the front and rear of the control box becomes shorter.

[Brief explanation of the drawing]

Figures 1 and 2 are an external side view and a plan view of an agricultural tractor embodying the present invention, Figure 3 is an enlarged front view of the main parts with the lower part of the seat cut away, and Figure 4 is viewed from the fuel tank side. FIG. 5 is an exploded perspective view of the transmission case, shift operation mechanism, and lever. FIG. 6 is an explanatory view showing the operating range of the shift operation lever. In addition, in the drawing, l is the vehicle body, 11 is the transmission case, and 17
is a seat, 21 is a hydraulic cylinder, 31 is a fuel tank, 3
6 is the upper surface of the tank, 37 is the recess, 41 is the sub-shift operating lever, 42 is the bent part, 43 is the fulcrum, 47 is the sub-shift operating shaft, 4
8 is a sub-shift operation mechanism, 51 is a PTO shift operation lever, 5
2 is a bending portion, 53 is a fulcrum, 57 is a PTO gear shift operation shaft, 5
8 is a PTO speed change operation mechanism.

Claims (1)

[Scope of Claims] 1. In an agricultural tractor in which a seat is arranged above a transmission case located at the rear of the vehicle body, a fuel tank is arranged on one side of the transmission case, and the transmission is inserted from the other side of the transmission case. A speed change operation device for an agricultural tractor, characterized in that a speed change operation mechanism is provided on the fuel tank side through between the upper part of the case and the lower part of the seat, and the speed change operation lever is provided on the side of the seat above the fuel tank. 2. The gear shift operating device for an agricultural tractor according to claim 1, wherein a recess through which the gear shift operating mechanism passes is formed in the upper surface of the fuel tank. 3. The agricultural tractor according to claim 1, wherein the speed change operation lever is composed of two levers, front and rear, with lower supporting points close to each other, and both levers have a bent part in the middle so that they intersect with each other in the operating range. Gear shift operation device.