JPH1033011A - Structure for lifting and lowering operation device of farm working machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance lightening and durability of a hydraulic cylinder and a quadruple link mechanism. SOLUTION: A hydraulic cylinder 2 is installed over a support P1 connecting upper links 7 in a quadruple link mechanism 3 to a vertical frame part 6 on the machine side and a support P4 connecting a pair of lower links 8 in the quadruple link mechanism 3 to a vertical link 9 in the rear and a lifting and lowering structure is constituted so as to carry out pulling up and raising operation of the quadruple link mechanism 3 by shortening operation of the hydraulic cylinder 2. Small-sized reinforcing members 30 are each stretchably installed over backward part than the front end of each lowering link 8 and a part deviated in the transverse direction near the shaft center of the front support P2 of the lower links 8 and the position at longitudinal ends of each reinforcing member 30 is set so that distance between both ends in each reinforcing member 30 does not change regardless of lifting and lowering of the quadruple link mechanism 3. Thereby, large transverse vibration of whole quadruple link mechanism 3 is controlled.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a working device lifting and lowering structure of an agricultural working machine in which a working device is connected to a rear portion of a traveling machine body via a four-link mechanism driven up and down by a hydraulic cylinder so as to be able to move up and down.

[0002]

2. Description of the Related Art A typical example of the above-described lifting and lowering structure of a working device of an agricultural working machine is a raising and lowering structure of a planting device of a rice transplanter. This planting device elevating structure is constructed such that a hydraulic cylinder is erected over the upper link of the four-link mechanism provided at the rear of the traveling body and the fuselage, and the hydraulic cylinder is extended and the upper link is pushed up to operate the hydraulic cylinder. The planting device (working device) connected to the rear link of the continuous link mechanism is configured to be driven up.

[0003]

In the above-described lifting structure, a compression load acts on the hydraulic cylinder when the working device is lifted, so that the hydraulic cylinder needs to have a strength that does not buckle against the compression load. In this case, large diameter cylinder cylinders and piston rods were used. Also, the upper link which receives the push-up of the hydraulic cylinder is required to have a considerably large bending strength, so that not only the hydraulic cylinder but also the components of the quadruple link mechanism itself are large and heavy.

[0004] The present invention is to improve the arrangement of the four-link mechanism and the hydraulic cylinder for driving the same, by reasonably improving the arrangement.
The main object is to increase the durability while reducing the weight of the hydraulic cylinder and the quadruple link mechanism.

[0005]

The structure, operation and effect of the invention according to claim 1 are as follows. (Structure) The invention according to claim 1 is a working device lifting and lowering structure of an agricultural working machine in which a working device is connected to a rear portion of a traveling machine body via a four-link mechanism driven up and down by a hydraulic cylinder so as to be able to move up and down. A hydraulic cylinder is spanned over a fulcrum connecting the upper link in the quadruple link mechanism and the vertical frame portion on the fuselage side, and a fulcrum connecting the pair of left and right lower links and the rear vertical link in the quadruple link mechanism, The four-link mechanism is raised and raised by the shortening operation of the hydraulic cylinder, and the four-link mechanism is lowered by the elongating operation of the hydraulic cylinder. A small-diameter reinforcing member is stretched over a portion deviated in the lateral direction near the axis of the front fulcrum, and the position of the front and rear ends of each reinforcing member is The distance between both ends of each reinforcing member is set so as not to change irrespective of the elevation of the link mechanism.

(Operation) According to the above configuration, a tensile load acts on the upper link, a compressive load acts on the lower link, a bending load acts on the rear vertical link, and a tensile load acts on the hydraulic cylinder. . Therefore, it is not necessary to consider buckling of the upper link to which only a tensile load is applied. In addition, a small diameter piston rod of a hydraulic cylinder to which only a tensile load is applied is sufficient. In addition, by using a member that is not particularly strong as a whole, the entire quadruple link mechanism relatively easily bends in the lateral direction and exhibits a function of buffering an impact load, but it has a function of damping an impact load. The left and right lower links are restricted from swaying inward or outward by the tension of a small-diameter reinforcing member such as a rod, a wire, or a chain stretched in a triangular shape. The entire large lateral runout is restricted, and it is possible to prevent the working device from largely laterally moving and coming into contact with another object due to vibration or shaking during traveling.

(Effect) According to the first aspect of the present invention,
The upper link to which no compressive load or bending load acts does not need to consider the buckling strength of the hydraulic cylinder, which only needs to consider the tensile strength. This is effective in reducing the weight and cost of the entire four-link mechanism including the hydraulic cylinder. In addition, while being a lightweight and inexpensive four-link mechanism as described above,
By rationally introducing a lightweight, small-diameter reinforcing member in which weight increase is of little concern, the strength against lateral loads can be secured and the practical effect is high.

The structure, operation and effect of the invention according to claim 2 are as follows. (Configuration) In the invention according to claim 2, in the invention according to claim 1, the two reinforcing members connected to the rear portions of the left and right lower links cross each other between the left and right lower links in a plan view, and each reinforcing member is connected to each other. The front end of the member is provided near the front end of each lower link. (Operation / Effect) According to this configuration, the reinforcing member for controlling the large lateral runout of the quadruple link mechanism can be made to function within substantially the width of the quadruple link mechanism or a width close thereto, which is effective in reducing the size of the structure. There is.

[0009]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows an overall side view of a riding rice transplanter as an example of an agricultural work machine. This rice transplanter is provided with a quadruple link mechanism 3 which is driven up and down by a hydraulic cylinder 2 at a rear portion of a traveling machine body 1 driven by four-wheel drive, and a four-row seedling planting device is provided at a rear portion of the quadruple link mechanism 3. (Working device) 4 is connected.

[0010] As shown in FIG.
An upper link 7 whose front end is pivotally connected via a fulcrum P1 to a pair of left and right vertical frame portions 6 erected at the rear of the body frame 5 of the traveling body 1; A pair of left and right lower links 8 pivotally connected via P2, and a rear vertical link 9 pivotally connected to the rear ends of the upper link 7 and the lower link 8 via fulcrums P3 and P4. The seedling planting device 4 is connected to and supported by a boss 10 provided below the rear vertical link 9 so as to be able to roll around the longitudinal axis X.

More specifically, as shown in FIG. 3, the upper link 7 is formed by arranging thin rectangular pipe members in parallel at a predetermined interval on the left and right sides. It is pivotally connected by one fulcrum shaft 11. Also, each lower link 8 is made of a square pipe material,
As shown in the figure, the boss 8 welded to each front end is fixed.
a is connected to a fulcrum shaft 12 provided in a cantilevered manner on the right and left rear portions of the body frame 5. The rear vertical link 9 is formed of a sheet metal processing member having a U-shaped cross section opened rearward, and the boss 10 is fixed to the lower end thereof by welding. The boss 9a fixed through and the boss 7a welded and fixed to the rear end of the upper link 7 are connected by a fulcrum shaft 13, and the boss 8b welded and fixed to the rear of the left and right lower links 8 and the rear vertical link 9 The boss 9b welded and fixed to the lower part of the fulcrum shaft 1
4 are connected.

The hydraulic cylinder 2 is of a single-acting type that is shortened by supply of pressurized oil. The front end of the cylinder cylinder 2a has a fulcrum shaft 11 at the connecting point between the upper link 7 and the vertical frame 6. Is pivotally connected and shared. That is, as shown in FIG. 4, the bosses 7b are fixed to the front ends of the left and right upper links 7 so as to penetrate, and the inward ends of both the bosses 7a face each other and are opposed to each other.
a, the base boss 2c welded and fixed to the front end of
a, the left and right bosses 6a fixed to the vertical frame 6 and the upper link 7 in this state.
A single fulcrum shaft 11 is inserted through the left and right bosses 7b.

At a fulcrum P4 at which the lower link 8 and the rear vertical link 9 are pivotally connected, the left and right ends of a support member 15 formed by bending a band plate material into a trapezoidal shape in plan view are connected to the fulcrum shaft 1.
4 for pivotal connection. Here, bosses 15a are provided on both left and right ends of the support member 15, and the boss 15a is connected to the boss 8b of the lower link 8 and the rear vertical link 9
Boss 9b. A piston rod 2b extending rearward from a cylinder cylinder 2a of the hydraulic cylinder 2 is slidably inserted into the center of the support member 15, and the piston rod 2b
Support washer 16 and support member 1 attached to the penetrating end of
A suspension spring 17 made of a compression coil spring is interposed between the suspension spring 17 and an intermediate portion of the fifth spring. A bush 18 made of a bearing metal or plastic is provided at the center of the support member 15 to slide the piston rod 2b with low resistance. The spring washer 1
The position 6 can be adjusted by a nut 19 mounted on the piston rod 2b, and the cushion function of the suspension spring 17 can be adjusted by this adjustment.

The lifting structure of the present invention is configured as described above. By operating a control valve (not shown) to supply hydraulic oil to the hydraulic cylinder 2 and shorten it, the four-link mechanism 3 is pulled up. The planting device 4 can be raised,
By draining the oil from the hydraulic cylinder 2 and performing the free extension operation, the quadruple link mechanism 3 can be swung down and the planting device 4 can be lowered by its own weight. Further, even in the neutral state where the shortening operation of the hydraulic cylinder 2 is stopped, the four-way link mechanism 3 is allowed to slightly move up and down within the elastic flexibility range of the suspension spring 17.

Here, considering the loads acting on each part of the quadruple link mechanism 3, a tensile load is applied to the upper link 7, a compressive load is applied to the lower link 8, a bending load is applied to the rear vertical link 9, and A tensile load acts on the hydraulic cylinder 2. Therefore, it is not necessary to consider the buckling of the upper link 7 to which only the tensile load is applied, and a thin member having sufficient strength to withstand the tensile load is sufficient. Also, a small diameter of the piston rod 2b of the hydraulic cylinder 2 to which only a tensile load is applied is sufficient. Further, since loads acting on both left and right ends of the support member 15 act near the end of the fulcrum shaft 14, a large bending load is not applied to the fulcrum shaft 14, and the fulcrum shaft 14
Can be a small diameter shaft.

Between the rear end of the lower link 8 of the quadruple link mechanism 3 and the front part of the planting device 4, the rolling operation of the planting device 4 when the quadruple link mechanism 3 is raised is mechanically limited. A rolling lock mechanism 20 is provided. That is, as shown in FIGS. 6 and 7, brackets 22 are provided on the left and right sides of a frame plate 21 provided at the front of the planting device 4, and the upper end fitting 23 a of the restraining rod 23 inserted through the bracket 22 is attached to the lower part. The rear extension 8c of the link 8 is connected to the front and rear elongated holes 24 and pins 25 via pins 25, and a pair of coil springs 26 and 27 are externally fitted to the restraining rod 23 above and below the bracket 22. The upper coil spring 26 has its upper end received and supported by a spring receiving washer 28 fixed to the restraining rod 23, and the lower coil spring 27 has its lower end received and supported by a spring receiving washer 29 whose position can be adjusted.

According to the lift control mechanism 20 having the above-described structure, the rear extension 8c of the lower link 8 swings upward about the fulcrum shaft 14 as the four-link mechanism 3 is raised. When the restraining rod 23 is lifted up and becomes close to the ascending limit of the quadruple link mechanism 3, as shown in FIG. 7, the left and right restraining rods 23 compress the lower coil spring 27 close to close contact, and as a result, The rolling operation of the planting device 4 around the longitudinal axis X is prevented from being restrained, and further upward movement is also prevented from being restrained. The pin 25 is displaced in the front-rear direction in accordance with the raising / lowering operation of the quadruple link mechanism 3, and this displacement is caused by the front-rear slot 2 formed in the upper end fitting 23a of the restraining rod 23.
4, the penetration angle of the restraining rod 23 with respect to the bracket 22 becomes substantially constant, and as a result, the restraining rod 23
Is prevented from being twisted at the insertion portion of the bracket 22.

A front fulcrum P2 of the lower link 8 on the left side.
Near and near the rear fulcrum P4 of the right lower link 8, and near the front fulcrum P2 of the right lower link 8 and near the rear fulcrum P4 of the left lower link 8, respectively. A reinforcing member 30 such as a thin rod, wire, or chain is stretched via a connection fitting 31 so as to intersect in a plan view. According to this, the left lower link 8 is restrained from laterally swaying to the left outside by the triangular reinforcing member 30, and the right lower link 8 is controlled to the right outer side by the triangular reinforcing member 30. Is restricted, and as a result, the entire four-link mechanism 3 is restricted from rolling. The reinforcing member 30 is provided with a tension tensioning device 32 such as a turnbuckle.
Is provided so as to provide an appropriate tension with no excess or deficiency in accordance with an assembly error, and to cope with a dimensional change between members over time, elongation of the reinforcing member 30 itself, and the like.

The connecting position of the rear end of the reinforcing member 30 is desirably near the rear fulcrum P4 of the lower link 8 in order to efficiently exert the lateral deflection control function, but is not necessarily limited to this. 8 as far as it is located behind the front fulcrum P2. Further, it is necessary to set the connection position of the reinforcing member 30 so that the distance between both ends of each reinforcing member 30 does not change irrespective of whether the quadruple link mechanism 3 moves up and down, and connects the front end of the reinforcing member 30 to the body side. in case of,
Each reinforcing member 30 is located on the axis of the front fulcrum P2 of the lower link 8.
Set the front end connection point of.

Further, in the above embodiment, the reinforcing member 30 is attached to the inside of the left and right lower links 8 so that each lower link 8
Is restricted by each reinforcing member 30,
It can also be hung outside the left and right lower links 8. For example, the front end connection position of the reinforcing member 30 connected to the rear part of the left lower link 8 is set on the axis of the front end fulcrum P2 of the lower link 8 at the part deviated to the lateral outside of the left lower link 8. The connecting position of the front end of the reinforcing member 30 connected to the rear portion of the lower link 8 on the right side is changed to the lower link 8
It is also possible to set each of them on the axis of the front end fulcrum P2. According to this, the inward run-out of each lower link 8 is regulated by each reinforcing member 30, and the lateral link of the entire four-link mechanism 3 is controlled. Shaking can be regulated.

[Brief description of the drawings]

FIG. 1 is an overall side view of a rice transplanter.

FIG. 2 is a side view of a quadruple link mechanism.

FIG. 3 is a plan view of a quadruple link mechanism.

FIG. 4 is a longitudinal rear view showing a front fulcrum of the quadruple link mechanism.

FIG. 5 is an exploded perspective view showing a front end fulcrum structure of an upper link.

FIG. 6 is a side view of a rolling lock mechanism.

FIG. 7 is a longitudinal rear view showing a rear fulcrum and a rolling lock mechanism of the quadruple link mechanism.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Traveling body 2 Hydraulic cylinder 3 Quadruple link mechanism 4 Work device 7 Upper link 8 Lower link 9 Rear vertical link 30 Reinforcement member P1 Support point (front of upper link) P2 Support point (front of lower link) P4 Support point (lower link Rear)

Claims (2)

[Claims] 1. A work equipment lifting / lowering structure of an agricultural work machine in which a work equipment is connected to a rear part of a traveling machine body via a four-link mechanism driven up and down by a hydraulic cylinder so as to be movable up and down. A hydraulic cylinder is spanned over a fulcrum connecting the link and the vertical frame portion on the fuselage side and a fulcrum connecting the pair of left and right lower links and the rear vertical link in the quadruple link mechanism, and the hydraulic cylinder is shortened. The four-link mechanism is raised and raised by the operation of the hydraulic cylinder, and the four-link mechanism is lowered by the extension operation of the hydraulic cylinder. And, the rear part from the front end of each of the lower links, and the axis of the front fulcrum of the lower link A small-diameter reinforcing member is stretched over the portion deviated in the lateral direction near the center, and the positions of the front and rear ends of each reinforcing member are raised by the four-link mechanism. Working apparatus lifting structure agricultural machine, characterized in that both end distance in each of the reinforcing members is set so as not to change regardless. 2. The two reinforcing members connected to the rear portions of the left and right lower links intersect between the left and right lower links in plan view, and the front end of each reinforcing member is disposed near the front end of each lower link. A lifting / lowering structure for a working device of an agricultural working machine.