JPH0314965Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial field of application> The present invention relates to a sideways flow prevention mechanism for a working machine in a tractor, and when performing work with the working machine free to move left and right, it is possible to keep the working machine in the correct position even on slopes. It is designed so that it can be held in a certain position.

<Prior art> When working by connecting a work machine to the rear of a tractor body via a three-point linkage mechanism with a pair of left and right lower links, the work machine is connected to a plow, a cultivator, a soil gardener, a seeding machine, etc. If so, the check chain that controls the left-right swing of each lower link is loosened, allowing the work equipment itself to swing left-right independently of the tractor body.

<Problem that the invention seeks to solve> If the work equipment is used on a slope with free left and right movement, the work equipment will drift sideways, making it impossible to work in a straight line even if the tractor is moving straight. .

<Means for Solving the Problems> The present invention was provided for the purpose of solving the above-mentioned conventional problems, and as a specific means for that purpose, a pair of left and right lower lowers are attached to the tractor body. In a device in which the work machine is connected via a three-point linkage mechanism equipped with links, at least one of the restraining means for restraining the left and right swinging of each pair of left and right lower links is a cylinder, and the work machine is prevented from moving sideways. The cylinder is extendable and retractable so that the working machine can move left and right, and a control valve is provided to operate the cylinder to return the working machine when the detecting means detects a lateral flow.

<Function> When using the working machine 8 such as a plow, a cultivator, a seeding machine, etc., the control valve 27 is set to the neutral position so that the working machine 8 can swing left and right. Therefore, when the work implement 8 receives lateral pressure and tries to drift sideways on a slope or the like, the detection means 37 or 38 is activated by hydraulic pressure or the like to detect this. Then, the cylinder 1 is detected by a signal from the detection means 37 or 38.
8, 19 are expanded and contracted, and this cylinder 18, 1
9 forcibly pushes back the working machine 8.

<Embodiment> Hereinafter, the present invention will be described in detail with reference to the illustrated embodiment. In FIG. 1, 1 is a tractor body, 2, 3 are
is the rear axle case, 4 and 5 are the final reduction cases, and 6 and 7
is the rear axle. 8 is a working machine, such as a plow,
These include cultivators, potters, seeders, etc. Reference numeral 9 denotes a three-point linkage mechanism for towing and attaching the work implement 8 to the rear of the tractor body 1, and is composed of a top link (not shown) and a pair of left and right lower links 10 and 11. The lower links 10 and 11 are the pivot shafts 1 on both sides of the tractor body 1.
2 and 13, and is also removably supported on mounting pins 14 and 15 of the working machine 8. 1
6 and 17 are check means for checking the left and right swinging of each lower link 10 and 11, and are composed of hydraulic cylinders 18 and 19, respectively, and the main body side thereof is connected to the pivot 1.
The lower links 10 and 13 are supported by pivot shafts 20 and 21 attached to the rear axle cases 4 and 5 on the same axis, and the rod side is connected to the middle part of the lower links 10 and 11. Note that ball joints are provided at both ends of the lower links 10 and 11 and on the main bodies of the hydraulic cylinders 18 and 19, respectively. Further, the hydraulic cylinders 18 and 19 are provided with potentiometers 22 and 23 that detect the amount of expansion and contraction thereof as an electric signal.

FIG. 2 shows the hydraulic circuit of the hydraulic cylinders 18 and 19, 24 is the engine, 25 is the hydraulic pump, 26
is a relief valve. Reference numeral 27 denotes an electromagnetic control valve, which has two solenoids 28 and 29, and is configured to communicate between the pump port and the tank port when in neutral. Reference numeral 30 denotes an electromagnetic switching valve for manual and automatic switching, which includes a solenoid 31 for automatic switching and a solenoid 32 for manual switching. The electromagnetic switching valve 30 connects the hydraulic cylinders 18 and 19 in series so that the distance between the pair of left and right lower links 10 and 11 is adjusted by the expansion and contraction of each hydraulic cylinder 18 and 19 when the solenoid 32 is energized. and when the solenoid 31 is energized, each hydraulic cylinder 18,
A pair of left and right lower links 10,
Both hydraulic cylinders 18 and 19 are connected in series so that both hydraulic cylinders 11 swing left and right in the same direction. Electromagnetic switching valve 30 and each hydraulic cylinder 18, 19
A throttle valve 35,
36 is interposed, and a pressure switch 3 is installed closer to the hydraulic cylinders 18, 19 than the throttle valves 35, 36, for detecting a lateral flow of the working machine 8 through changes in oil pressure.
7 and 38 are provided. Note that the pressure switches 37 and 38 constitute a detection means.

FIG. 3 shows a control circuit, and 39 is a comparator, which determines that the work implement 8 is located at the center of the left and right sides when the signals from the potentiometers 22 and 23 match. 40 is a manual/automatic selection switch, and 41 is a manual switch. Reference numeral 42 is a drive circuit for the solenoids 28, 29, 31, and 32, and when manual is selected with the selection switch 40, the manual switch 4 is turned on.
When 1 is operated, solenoid 32 and solenoid 28 or 29 can be driven, and selection switch 4 can be driven.
If automatic is selected at 0, the solenoid 31 of the electromagnetic switching valve 30 will be driven, and when the pressure switch 37 or 38 is activated, the solenoid 28 or 29 of the electromagnetic control valve 27 in the corresponding direction will be driven. ing. Note that the solenoids 28 and 29 are driven until the comparator 39 determines that the work implement 8 has returned to the center.

In the above configuration, when attaching or detaching the working machine 8, after selecting manual with the selection switch 40, the manual switch 41 is operated in the expansion/contraction direction. Then, the solenoid 32 is energized, the solenoid switching valve 30 is switched to the manual side, and the solenoid 2 of the solenoid control valve 27 is energized.
8 or 29 is excited, each hydraulic cylinder 18, 19
operates to adjust the distance between the pair of left and right lower links 10, 11. Therefore, the working machine 8 can be easily and reliably attached to and detached from the tractor. After installing the work equipment 8, when the manual switch 41 is turned off, the electromagnetic switching valve 30 becomes neutral and locks each hydraulic cylinder 18, 19. Therefore, if the work equipment 8 is a rotary device, it can be moved from side to side. Can be fixed immovably.

If the working machine is a plow, etc., select switch 4.
0 is set to automatic, and work is carried out with the working machine 8 in a state where it can freely move left and right. That is, when the selection switch 40 is set to automatic, the solenoid 31 of the electromagnetic switching valve 30 is energized and switched to the automatic side, and each hydraulic cylinder 18, 19 is unlocked, so that the work implement 8 can move left and right by itself. It becomes possible to move freely.

When the working machine 8 receives lateral pressure when working on a slope or the like, the hydraulic cylinders 18 and 19 are in an unlocked state, so that the working machine 8 moves freely.
Therefore, for example, when the work implement 8 attempts to flow horizontally to the right (arrow a) due to side pressure, the internal pressure on the cylinder chamber 19a side of the right hydraulic cylinder 19 increases, and the pressure switch 38 detects this. Then, the drive circuit 42 is activated by the signal from the pressure switch 38, and the solenoid 29 of the electromagnetic control valve 27 is energized. The oil from the right hydraulic cylinder 19 enters the left hydraulic cylinder 18 through the hydraulic cylinder 19 on the right. Therefore, the right hydraulic cylinder 19
expands, and the left hydraulic cylinder 18 contracts, forcibly pushing the work implement 8 back toward the center. When the hydraulic cylinders 18 and 19 expand and contract, the potentiometers 22 and 23 are linked to the expansion and contraction operations. When the work implement 8 is located at the center of the left and right sides, the signals from the potentiometers 22 and 23 match, so a stop signal is sent from the comparator 39 to the drive circuit 42, the solenoid 29 is demagnetized, and the electromagnetic control valve 27 is
returns to neutral. With this series of controls,
It is possible to prevent the working machine 8 from flowing sideways, and also absorb mechanical looseness of each part.

In the above embodiment, the occurrence and directionality of cross flow is detected and determined by the operation of the pressure switch 37 or 38, but as shown in FIG. It may also be determined. That is, potentiometer 2
The comparator 39 compares the signals No. 2 and 23, and the determination circuit 43 determines whether the comparison value is positive or negative, thereby determining the directionality of the lateral flow of the work implement 8. Further, the comparison value is input to the comparison circuit 44 and compared with the signal of the allowable drift range set by the setting device 45, and when the comparison value exceeds the allowable range, it is possible to detect the occurrence of cross flow.

As shown in FIG. 5, one of the restraining means 16 and 17 of the lower links 10 and 11 is connected to the hydraulic cylinder
9, and the other is the same check chain 4 as before.
It is also possible to set it to 6.

In this case as well, as shown in FIG. 6, throttle valves 35 and 3
6 is interposed, and pressure switches 37, 38 are connected from the throttle valves 35, 36 to the hydraulic cylinder 19 side.
is connected. And pressure switch 37 or 3
8 detects a lateral flow of the work equipment 8, the drive circuit 4
The solenoid 28 or 29 of the electromagnetic control valve 27 is energized via the solenoid 7 or 48, and the working machine 8 is pushed back in the same manner as described above by the expansion and contraction movement of the hydraulic cylinder 19. Then, when the neutral detector 49 detects neutral, the solenoid 28 or 29 is demagnetized. In addition,
50 is a manual switch, and solenoids 28, 2
9 can be selectively excited. , the check chain 46 is used in a slack state. As long as the pressure switch 37 or 38 can detect positive pressure and negative pressure, either one may be used.

A ridge detection means for detecting the ridges of crops is provided on the tractor body 1 side, and the output of this ridge detection means causes the hydraulic cylinders 18 and 19 to move the work implement 8 along the ridge.
You may also add a function to control expansion and contraction.

<Effects of the invention> According to the invention, when the work equipment is used in a state where it can freely move left and right, the horizontal flow of the work equipment is detected and the cylinder is forced to return it, so it can be used on slopes, etc. This reduces meandering of the work equipment and improves straight-line performance even when working in the area.

[Brief explanation of the drawing]

Fig. 1 is a plan view showing the first embodiment of the present invention, Fig. 2 is a hydraulic circuit diagram thereof, Fig. 3 is an electric circuit diagram thereof, and Fig. 4 is an electric circuit diagram showing a second embodiment of the invention. , FIG. 5 is a plan view showing a third embodiment of the present invention, and FIG. 6 is a control circuit diagram thereof. 1... Tractor body, 8... Work equipment, 9... Three-point link mechanism, 10, 11... Lower link, 1
6, 17... check means, 18, 19... hydraulic cylinder, 27... electromagnetic control valve, 30... electromagnetic switching valve, 37, 38... pressure switch.

Claims (1)

[Scope of utility model registration request] In a vehicle in which a work machine is connected to a tractor body through a three-point linkage mechanism having a pair of left and right lower links, at least one of the restraining means for restraining the left and right swinging of each of the pair of left and right lower links. is a cylinder, is provided with a detection means for detecting a lateral flow of the working machine, is made telescopic so that the working machine can move left and right, and is a control valve for operating the cylinder to return the working machine when the detection means detects a lateral flow. A lateral flow prevention device for a working machine, characterized by being provided with.