JPS5936974Y2 - Agricultural tractor top link hinge - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a top link hinge for pivotally supporting the top link on the rear surface of the tractor in a three-point link type work implement mounting device for an agricultural tractor.

Conventional top link hinges are often fixed with bolts to the rear surface of a hydraulic case fixed to the upper part of a transmission case, as shown in FIG.

However, tensile and compressive forces are repeatedly applied to the top link hinge based on the rotation of the work equipment via the top link, and in order to withstand this, the top link hinge must be installed not only with bolts but also with bolts. Furthermore, it was necessary to increase the number of bolts and use larger bolts to attach the hydraulic case that supports it to the transmission case.

In order to eliminate these drawbacks, the present invention integrates the hydraulic case with the transmission case, and in order to compensate for the narrow mounting surface of the top link hinge, a horizontal mounting body is installed on the top link. and a vertical mounting body, and is constructed so that the tensile force and compressive force applied to the top link hinge are supported on both sides by the shear force and tension of the bolt,
It has increased durability.

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 agricultural tractor.

The engine 2 is placed inside the hood 1, and the engine 2
The front axle bracket 3 protrudes from the lower side surface.

A front differential case 4 is pivotally supported on the front axle bracket 3 via a center pin, and both sides of the front differential case support front wheels 5.5.

A front wheel drive shaft device 6 transmits power to the front wheel differential case 4 from a transmission case 8 through a clutch housing 7.

A clutch housing 7 is fixed to the rear end surface of the engine 2,
A transmission case 8 is fixed to the rear surface of the clutch housing 7 with a center plate 9 sandwiched therebetween.

A rear axle 10 is supported on a transmission case 8, and a rear wheel 11.
11 is installed on the rear axle 10.

The transmission case 8 integrally incorporates a hydraulic case, which was conventionally press-fitted onto the upper part of the transmission case, and is not provided as a separate hydraulic case.

Only the portion of the lift arm 16 into which the lifting shaft 15 is fitted has a protruding portion 8a that protrudes.

A seat 18 is provided on the upper surface of the mission case 8, and a PTO shaft, a PTO shaft cover 14, a drawbar 20, and a three-point link type work machine mounting device are provided on the rear surface of the mission case 8.

The three-point link type work equipment mounting device consists of a lift arm 16 and a lift link 17 that move the top link 130, the lower link 12, 12, and the rower 1 nonk up and down. This relates to the top link hinge 21.

In the present invention, the top link hinge 21 is located between the rear surface of the transmission case and the upper surface of the protrusion 8a perpendicular to the rear surface of the transmission case.
It is fixed on two perpendicular sides.

FIG. 7 shows the shape of the mission case 8. Unlike the conventional case, a hydraulic case is not provided separately, but a hydraulic device is built inside the upper part of the mission case.

The hydraulic system includes a directional control valve 25, a cylinder 26, a piston 24, a piston rod 23, a rod arm 22, and a cylinder 26 which is disposed from the lift arm shaft 15 and is provided within the thickness of the transmission case 8.

There is no problem in placing the lift arm shaft 15 in a low position, but since the PTO gearbox of the PTO shaft is built inside the rear end of the mission case 8, a part of the mission case 8 must be moved to prevent the rod arm 22 from engaging. The protruding portion 8a is provided in a protruding manner.

The top link hinge 21 is fixed to the top and rear surfaces of this protrusion 8a.

FIG. 6 is a drawing showing the structure of a conventional top link hinge and hydraulic system.

Conventionally, a separate hydraulic case was fixed on the upper machined surface of the transmission case 8, and the top link hinge 20 was fixed to the rear part of the hydraulic case.

It is impossible to fix the top link hinge 21 across the joint surface of the hydraulic case and the transmission case because both sides are not co-processed and there is a slight difference in the heel. It was attached only to the rear.

As a result, the vertical mounting body 21 needs to have a wide mounting surface and is made of a thick material.6 Figures 2 to 5 show the structure of the top link hinge 21 of the present invention.

FIG. 2 is a side view, FIG. 3 is a plan view, FIG. 4 is a rear view, and FIG. 5 is a front view.

The top ring hinge 21 is formed by a pair of hinge bodies 21a, a vertical mounting body 21b, and a pair of horizontal mounting bodies 21c, and the horizontal mounting body 21c is provided at the vertical center position of the bolt hole 21f of the vertical mounting body 21b.

With this configuration, installation is possible even if the top link hinge body 21 is replaced by 2,000 inches, and the top link hinge can be moved up or down depending on the work machine, making it possible to install it on tall or short work machines. The top link device can be adjusted to obtain the optimum rotation trajectory.

As described above, in the present invention, the mission case 8 and the hydraulic case are integrally formed, and the directional control valve 25, the cylinder 26, the piston 24, the piston rod 23, the rod arm 22, and the lift arm shaft 15 are provided inside the upper part of the mission case. etc., the lift arm shaft 15 is pivotally supported at the upper rear corner of the mission case, and a top consisting of a horizontal mounting body and a vertical mounting body is mounted on two perpendicular surfaces, horizontal and vertical, of the upper rear corner of the transmission case. Since the link hinge 21 can be attached interchangeably between upper and lower positions, the following effects are achieved.

First of all, if the transmission case and the hydraulic case are constructed integrally, it is limited to the casting mold, and it is not possible to construct only the hydraulic case portion with a thicker side wall. This causes a lack of strength in the branches.

In the present invention, the top and rear surfaces of the protruding portion 18a, which are prone to cracking due to the pivot portion of the lift arm shaft, can be fixed and reinforced by the vertical mounting body 21b and horizontal mounting body 21c of the top link hinge, and the transmission case and hydraulic This allows the case to be integrated.

Secondly, since the transmission case and hydraulic case are integrated, the position of the hydraulic case can be lowered, but on the other hand, the height of the top link mast on the work equipment side remains the same as before. There are cases where the top link hinge is at a low position and the desired rotation cannot be obtained when rotating and lifting the lift arm of the work equipment. On the other hand, by making it possible to install the pin hole 21d of the top link hinge 21.
This makes it possible to position the transmission case and the hydraulic case upward, which makes it possible to eliminate the problems that occur when the transmission case and hydraulic case are integrated.

[Brief explanation of the drawing]

Figure 1 is an overall side view of the agricultural tractor, Figure 2 is a side view of the top link hinge, Figure 3 is a top view, Figure 4 is a rear view, Figure 5 is a front view, and Figure 6 is a side view of the top link hinge. FIG. 7 is a drawing showing a conventional top link hinge, and FIG. 7 is a drawing showing a transmission case of the present invention. 8...Mission case, 13...Top link, 16...Lift arm, 21...
...Top link hinge, 21a...Hinge body, 21b...Vertical mounting body, 21c...
・Horizontal mounting body.

Claims (1)

[Scope of utility model registration request] The transmission case 8 and the hydraulic case are integrally formed, and the directional control valve 25, cylinder 26, piston 24, piston rod 23, rod arm 22, lift arm shaft 15, etc. are built inside the upper part of the mission case. A lift arm shaft 15 is pivotally supported at the upper rear corner of the mission case, and a top link hinge 21 consisting of a horizontal mounting body and a vertical mounting body is mounted vertically and vertically on two perpendicular surfaces, horizontal and vertical, of the rear upper corner of the transmission case. Top link hinge 0 for agricultural tractors, which is characterized by the fact that it can be attached with interchangeable characteristics.