JP2001320908A - Top link bracket structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a top link bracket structure which can support a top link on the rear portion of a tractor in both standard and specific three point link hitch mechanisms for liftably linking a working machine to the tractor. SOLUTION: In the three point link hitch mechanism comprising a top link 6 and a pair of right and left lower links 7 which are used for linking a working machine 3 to a tractor 2, a top link bracket 5 fixed to the tractor 2 for supporting the top link 5 is formed so that a distance α between rear specific upper link pin holes formed in the right and left side frames 36L, 36R of the top link bracket 5 is larger than a distance β between the front standard upper link pin holes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a three-point link hitch mechanism for mounting a working machine at the rear of a tractor.
The present invention relates to a structure of a top link bracket for attaching a top link to a rear part of a tractor.

[0002]

2. Description of the Related Art A work machine directly mounted on a tractor is mounted on a rear portion of a tractor through three points of links, and the left and right lower links in the three-point link hitch mechanism are moved up and down by a hydraulic device, so that a working state is maintained. The lifting and lowering operation of the working machine for adjusting the tilling depth of the work and lifting it from the field is performed.

The three-point link hitch mechanism includes a top link and a pair of left and right lower links. The front end of each link is rotatably connected to the rear of the tractor, and the rear end is rotatably connected to a working machine. The types of the three-point link hitch mechanism include a standard three-point link hitch mechanism and a special three-point link hitch mechanism. The standard three-point link hitch mechanism can raise and lower the work equipment in a state close to the parallel four-bar link hitch mechanism, and has the advantage that the posture of the work equipment can be maintained substantially constant even when the working depth is changed. Is difficult to lift high from the field. In contrast, the special three-point link hitch mechanism connects the top link, which is sufficiently shorter than the lower link, to the bracket fixed to the tractor so that the work equipment can be lifted up as it rises. However, it is easy to work in narrow fields in Japan.

The above-mentioned two types of three-point link hitch mechanisms are used properly depending on the purpose of work. The standard three-point link hitch mechanism is mainly used for plowing work and the like, and the special three-point link hitch mechanism is used for rotary plowing work and the like. . As the length of the top link, a top link having a length according to the type of the working machine is used, and the length of the top link itself can be adjusted, and the mounting position is adjusted by the top link bracket. When attaching a work implement to a tractor using the standard three-point link hitch mechanism, attach the standard three-point link top link to a bracket fixed to the rear of the tractor. Also,
As shown in FIG. 6, when the work machine is mounted on the tractor by the special three-point link hitch mechanism, a special three-point link bracket (hereinafter, link hitch) is fixed to the bracket with a pin, and the special three-point link is used with the link hitch. We support the top link.

[0005]

The rear part of the three-point link hitch mechanism and the working machine are connected at three hitch points, and the swing of the working machine can be permitted at the hitch points. Therefore, when the work machine is mounted with the above-mentioned special three-point link, the swing of the work machine causes play between the bracket and the link hitch, thereby causing wear of the pin hole or movement of the top link attachment point. This causes vibration and noise of the drive shaft. Therefore, there has been provided a rattling suppressing mechanism such as binding the bracket and the link hitch to each other with a rattling suppressing bolt and holding metal.

However, the bracket having the above-mentioned backlash suppressing effect has many components, and when replacing the standard three-point link and the special three-point link, the attachment and detachment of the link hitch and the backlash suppressing mechanism member are complicated. Due to tying the bracket and link hitch at the time of three-point link,
There was a problem that the top link support point shifted.

A top link bracket that can be commonly used for the standard three-point link hitch mechanism and the special three-point link hitch mechanism is known from Japanese Utility Model Laid-Open No. 63-4608. When the work was lowered and the work implement was lowered to the bottom with the top link attached to the mounting hole, the top link and the top link bracket might contact and damage the work when the work was shaken to the left or right. . When the special three-point link hitch mechanism is used, the strength may be insufficient when the working machine is heavy.

[0008]

The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

That is, in the first aspect, the top link bracket for supporting the top link at the rear of the tractor in the three-point link type hitch mechanism for mounting the working machine on the tractor is provided by a standard three-point link hitch mechanism and a special three-point hitch mechanism. This is a structure that can be used commonly with the link hitch mechanism. The top link bracket is composed of a pair of left and right side frames, a pin hole for a standard three-point link mechanism on the base side, and a special three-point link hitch mechanism on the tip side. A pin hole is provided in each side frame, and the width of the pin hole for the special three-point link hitch mechanism is made larger than the width of the pin hole for the standard three-point link mechanism.

[0010]

Next, an embodiment of the present invention will be described. FIG. 1 is a rear side view of a tractor employing a top link bracket structure according to the present invention, and FIG. 2 is a plan view of the same. 3 is a side view of the bracket according to the present invention at the time of a special three-point link, FIG. 4 is a plan view of the same, and FIG. 5 is a plan view of the bracket according to the standard three-point link of the bracket according to the present invention. FIG. 6 is a side view of a conventional bracket at the time of a special three-point link.

In FIG. 1 and FIG. 2, a top link bracket adopting the bracket structure of the present invention is fixed to the rear of the tractor 2, and a rotary tillage device 3 is mounted as a working machine via a special three-point link hitch mechanism. The state is shown. Therefore, with the special three-point link hitch mechanism in this embodiment, the rotary tilling device 3 as a working machine can be raised and lowered substantially in parallel within the tilling use range, so that it can be raised to a position higher than the ascending position beyond the tilling use range. I have. The rotary tiller 3 mounted on the rear of the tractor 2 includes:
When power is transmitted to the input shaft of the gear box 21 of the rotary tilling device 3 via the drive shaft (universal joint) 19 by the PTO shaft 20 protruding from the rear of the tractor 2, the rotation direction in the gear box 21 is changed. The power is transmitted to the chain case 26 by the main beam 29. On the lower part of the main beam 29, the tilling claw 27
Is radially implanted, and the tilling claw shaft 28 is laid horizontally. The tine is wound around the main beam 29 and the sprocket fixed to the end of the cultivating claw shaft 28 in the chain case 26 to the cultivating claw shaft 28. Power is transmitted.

The main beam 2 of the rotary tilling device 3
The mounting stays 30 and 3 are provided on the left and right halfway of 9.29 respectively.
0 is welded and fixed, and the depth frames 43 are pivotally connected to the rear of the mounting stay 30 via a "-"-shaped stay in plan view. The depth frames 43 are linked to a handle 25 of the upper arm 22 via an adjusting screw 44, and the depth frames 43 are moved up and down by operating the handle 25. A lower hitch pin 18 forming a lower hitch point in front of the mounting stay 30 is a lower link 7 serving as a pin mounting mechanism using the mounting stay 30 and a spherical bearing.
Through the hitch. Therefore, lower link 7
Is rotatable about the lower hitch pin 18 at the lower hitch point. The left and right mounting stays 30 equipped with the depth frames 43 and the lower links 7.7 respectively.
Reference numeral 30 is symmetrical in plan view with the top link 6 substantially at the center.

In the upper arm 22 of the rotary tilling apparatus 3, the upper hitch pin 16 forming the upper hitch point penetrates the left and right upper arms 22 with the rear hitch portion 6b of the top link 6 interposed therebetween. Upper hitch pin 16
Are prevented from falling off by the snap pins 15. The rear hitch portion 6b of the top link 6 is a pin mounting mechanism using a spherical bearing, and the top link 6 is rotatably supported at the upper hitch point. The top link has a structure in which the length can be adjusted by a mechanism using a forward / reverse screw (turn buckle), so that the mounting angle to the working machine can be finely adjusted. The upper hitch point is located slightly ahead of the lower hitch point, and the three hitch points form a triangle in rear view.

On the other hand, in the tractor 2,
Projecting the PTO shaft 20 rearward from the transmission case of
Above this, the top link bracket 5 of the present invention is screwed and fixed. In the top link bracket 5, a front link portion 6a of the top link 6 is pivotally connected to a hole opened in the top link bracket 5 by an upper link pin 13 to form an upper link point. The tractor 2 has a hydraulic lifting device 10 for lifting and lowering the work implement 3 mounted on the upper portion of the transmission case. The lift arm 9 of the hydraulic lifting device 10 projects to the rear of the tractor 2, and the tip of the lift arm 9 A lift rod 8 is pivotally connected, and the lift rod 8 is pivotally connected to an intermediate portion of the lower link 7 before and after. By selecting one of the plurality of connection holes formed in the lift rod 8, the length of the lift rod can be adjusted, and the lift arm 9 is connected to the lift arm 8 at the connection point 46 between the lift rod 8 and the lower link 7. Fine adjustment of the inclination angle with the lower link 7 is performed. The lower link 7 is provided with a lower link pin 17 pivotally supported at the rear of the tractor 2.
The lower link point is formed by being rotatably supported around the shaft, and when the lift arm 9 is rotated by the hydraulic elevating device 10, the lower link 7 is pivotally moved through the lower link pin 17 via the lift rod 8. To rotate.

By configuring a three-point link as described above,
In conjunction with the rotation of the lift arm 9, the left and right lower links 7 rotate about the lower link pin 17 as an axis, and the top link 6
Is rotated about the upper link pin 13 in association with the rotation of the lower link 7, so that the rotary tilling device 3 is raised or lowered.

Here, the structure of the top link bracket 5 according to the present invention will be described in detail. As shown in FIGS. 3 and 4, the top link bracket 5 includes a base frame 35 for screwing to the rear of the tractor 2, a pair of left and right side frames 36 </ b> L and 36 </ b> R, and a reinforcing portion 32 for reinforcing the top link bracket 5. ing. Base frame 35
Are arranged at the front ends of the side frames 36L and 36R in the vertical direction on the left and right, and are configured in a square shape in plan view. The reinforcing part 32 is connected and fixed to the lower surface of the middle part of the side frames 36L and 36R.

The side frames 36L and 36R of the top link bracket 5 are bilaterally symmetric with respect to the approximate center of the top link bracket 5 in a plan view. In each of the left and right side frames 36L and 36R, a standard is provided at a base (front). Standard upper link hole 39 for inserting the top link by inserting the upper link pin in the three-point link hitch mechanism.
A special upper link hole 38 for attaching a top link in a special three-point link hitch mechanism is drilled at the front end (rear) of the vehicle. 36L left and right side frames
36R is configured such that the width of the rear portion widens right and left with the central portion being a slope, and the width (distance) of the special upper link hole portion (distance) is larger than the standard upper link hole portion (distance) β of the left and right side frames 36L and 36R. ) Α is increased. In other words, the left and right widths of the top link bracket 5 are made wider at the rear, and the standard upper link holes 39, 39, 39 and the special upper link hole 38 are provided, and the top link is attached to the top link mounting portion. Have been.

With such a configuration, the top link bracket 5 receives the load of the working machine 3 and the load at the time of work. However, the top link bracket 5 of the present invention comprises the base frame 35, the side frames 36L and 36R and the reinforcement. Since the portion 32 is integrally formed by welding or the like, it has a structure that is not easily deformed. In addition, by using only one component member, it is possible to eliminate problems such as backlash and abrasion that occur at a connection point between the members in the conventional special link bracket 62 configured of a plurality of members illustrated in FIG. It is.

Here, in the three-point link hitch mechanism of both the special three-point link and the standard three-point link, the support structure of the top link by the top link bracket of the present invention will be described. First, a case of a special three-point link hitch mechanism will be described with reference to FIGS. The top link 6α for the special three-point link is a link portion 6 of the top link 6α.
a, a spherical bearing is provided, and the upper link pin 13 is provided in the special upper link hole 38 of the top link bracket 5, and the collar 3 is provided on both sides of the top link 6α and the upper link pin 13.
1 and 31, and is prevented from falling off by the snap pin 14. Collars 31.3 are provided on both sides of the top link 6α rotatably supported by the top link bracket 5.
1, the top link 6α is positioned so as to be located at the center in the left-right direction.

Next, a case where a standard three-point link hitch mechanism is used will be described with reference to FIG. Top link 6 for standard three-point link compared to top link 6α for special three-point link
β is long, and both top links 6α and 6β can be finely adjusted in length by a mechanism using forward and reverse screws provided on the main pipe. The top link 6β for the standard three-point link is a side frame 36L / 36 of the top link bracket 5.
In the standard upper link holes 39, 39, 39 provided at the front of R,
It passes through the upper link pin 13 and is supported by the upper link pin 13. An end of the upper link pin 13 is prevented from coming off by a snap pin 14.

When working with the tractor 2 in this mounted state, the working machine 3 at the rear of the tractor 2 swings depending on the type of the working machine 3 to be mounted or a change in posture during the working. In a conventional top link bracket 62 shown in FIG. 6, a link hitch 52 is attached to a top link bracket 51 used for a standard three-point link hitch mechanism by pins 61.
And the top pin 6 for the special three-point link is supported by the upper link pin 56 and the snap pin 53 in the upper link hole 55 of the link hitch 52. When the standard three-point link hitch mechanism is used, the link hitch 52 is removed and the top link 6 is supported by the upper link hole 54.

In contrast to the conventional top link bracket 62, the top link bracket 5 of the present invention has the top link 6 which responds to the swing of the work machine 3, and the two-dot chain line 6 in FIG.
Even if it swings as shown by β ', the top link bracket 5
The special upper link pin hole distance α is larger than the standard upper link pin hole distance β drilled in the left and right side frames 36L and 36R.
Are formed so as to correspond to the swing width of the top link 6, so that the side frames 36 </ b> L and 36 </ b> R of the top link bracket 5 do not hinder the swing of the top link 6.

[0023]

The present invention is configured as described above.
The following effects are obtained. That is, a top link bracket for supporting a top link in a rear part of a tractor in a three-point link type hitch mechanism for mounting a working machine on a tractor is provided by a standard three-point link hitch mechanism and a special three-point link hitch. The top link bracket is composed of a pair of left and right side frames, a pin hole for a standard three-point link mechanism on the base side, and a pin hole for a special three-point link hitch mechanism on the tip side. Is provided on each side frame, and the left and right widths of the pin holes for the special three-point link hitch mechanism are made larger than the widths of the pin holes for the standard three-point link mechanism so that the standard three-point link hitch mechanism can be obtained. The top link is mounted on the tractor, and the work equipment swings when working with the tractor. Swing will not inhibit the is had disappeared even damaging. Thus, the same bracket can be used for both the standard and special three-point link hitch mechanisms, eliminating the need to replace the bracket depending on the type of link. Also, link switching can be easily performed, which contributes to cost reduction.

[Brief description of the drawings]

FIG. 1 is a rear side view of a tractor employing a top link bracket structure according to the present invention.

FIG. 2 is a plan view of the same.

FIG. 3 is a side view of the bracket according to the present invention at the time of a special three-point link.

FIG. 4 is a plan view of the same.

FIG. 5 is a side view of the bracket according to the present invention at the time of standard three-point link.

FIG. 6 is a side view of a conventional bracket at the time of a special three-point link.

[Description of Signs] 2 Tractor 3 Work implement 5 Bracket 6 Top link 7 Lower link 36L / 36R Side frame

Claims (1)

[Claims] 1. A standard three-point link hitch mechanism and a special three-point link hitch mechanism share a top link bracket for supporting a top link in a rear part of a tractor in a three-point link type hitch mechanism for mounting a working machine on a tractor. The top link bracket is composed of a pair of left and right side frames, and a standard three-point link mechanism pin hole is provided on the base side, and a special three-point link hitch mechanism pin hole is provided on the tip side. A top link bracket structure provided on a frame, wherein the left and right widths of the pin holes for the special three-point link hitch mechanism are larger than the widths of the pin holes for the standard three-point link mechanism.