JPS6167404A - Automatic deep plowing control apparatus of tractor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to an improvement in an automatic plowing depth control device that is applicable to tractors and the like.

BACKGROUND OF THE INVENTION A conventional automatic plowing depth control device for a tractor or the like is equipped with a sensor on the undercarriage of the working machine to detect changes in plowing depth by the working machine.

This is based on the opinion that it is appropriate to detect changes in plowing depth at a position near the work equipment that is in contact with the ground, and a sensor that detects the degree of change in plowing depth based on the rotation angle of the rear cover is used. It is installed. Then, a hydraulic cylinder is actuated in response to a signal from the sensor to raise and lower the working machine, thereby automatically adjusting the vertical direction.

Problems to be Solved by the Invention However, such conventional systems involve the inconvenience of having to attach a rear cover in all cases. This is because a burr cover may not be necessary depending on the type of work.

Also, the movement of the rear cover varies depending on the hardness and softness of the soil. The harder the cover, the greater the rotation angle of the cover. This is undesirable in terms of tillage work.

Furthermore, since the sensor and the hydraulic cylinder for driving the working machine are separated and there is a movable part between them, a problem arises in the signal transmission path.

The present invention has been made in view of the above-mentioned circumstances, and is intended to eliminate changes in plowing depth by installing a sensor on the tractor-shape machine side, not on the working machine side, to detect the inclination of the working machine. be. This is intended to provide effects such as making it unnecessary to attach a rear cover or the like.

Means for Solving the Problems: A hydraulic cylinder 22 for raising and lowering the working machine 14 and a sensor 36 for detecting changes in the plowing depth of the working machine are provided, and a signal from the sensor operates the hydraulic cylinder to perform plowing due to the above-mentioned inclination. In an automatic plowing depth control device for a tractor or the like that corrects changes in depth, the above-mentioned sensor is configured with a tilt sensor 36 that detects two states of forward tilt and backward tilt, and the sensor is connected to the main machine side of the tractor or the like. A rack 38 is installed on the ground and moves as the hydraulic cylinder is driven, and a pinion 40 that engages with the rack and the sensor are arranged so that the sensor changes its posture to a horizontal position regardless of the operation of the rack by the hydraulic cylinder. The above-mentioned control device is characterized in that the control device is connected by a power transmission mechanism 42 that obtains the power.

In order to carry out work using a tractor or the like, the plowing depth of the work implement 14 is first set by operating the position control lever 34. The displacement of the lever 34 causes the tilt sensor 36 to tilt, but since the power from the hydraulic cylinder 22, rack 38, and pinion 40 is transmitted via the differential gear 42, the tilt is canceled and the sensor 36 remains horizontal. maintain condition.

Suppose, therefore, that there is a depression in the ground halfway through the work, and the front wheel 12 gets stuck in the depression, causing the rotary 14 to float a little higher. At this time, the tilt sensor 36 detects the forward tilt and sends a signal to the controller 44. The controller 44 moves the solenoid valve 46 to drive the hydraulic cylinder 22, thereby lowering the rotary 14 a little. Along with this, the movement of the rack 38 and pinion 40 attempts to return the inclination of the inclination sensor 36 to the horizontal state via the differential gear device 42. When the tilt sensor 36 detects the horizontal state, the hydraulic cylinder 22, rack 38, etc. stop moving.

When the tractor returns to the horizontal state again, the inclination sensor 36
detects the opposite inclination, so the rotary 14 is driven by the hydraulic cylinder 22 to rise slightly.

Embodiments Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows an automatic plowing depth control device according to the present invention. The device is mounted on a tractor as illustrated in FIG.

First, to explain the tractor body, in FIG. 2, 10 is a rear wheel and 12 is a front wheel, which hold the body of the tractor. A working machine 14 such as a rotary crane is connected to the rear of these.

16 is a lower link for making the connection.

18 is a universal joint for transmitting power from the PTO shaft 20 of the tractor to the working machine 14.

If the work implement 14 is a rotary type, it must be raised and lowered relative to the main tractor in order to adjust the plowing depth.

22 is a hydraulic cylinder for raising and lowering the cylinder, 24
is a cylinder mast for guiding and regulating the expansion and contraction movement of the rod 26 of the cylinder. 28 is a lift link that connects the loft 26 and the lower link 16, and 30 is an upper link that connects the lift link 28 and the working machine 14.

32 is a seat where the driver sits, and when the driver operates the position control lever 34,
The hydraulic cylinder 22 is driven, and the rod 26, lift link 28, lower link 16, etc. move from the solid line position to the chain line position to raise the work equipment 14, and by operating the lever in the opposite direction, the work equipment is lowered. .

When working with a tractor, the lever 34 is operated to raise and lower the working machine, fix it at an appropriate position, and set the plowing depth. After that, the machine starts traveling, but the machine body tilts due to the unevenness of the ground while traveling, and the working machine also tilts accordingly, so it is not always possible to obtain a constant plowing depth.

Therefore, in order to compensate for changes in plowing depth due to tilting of the machine,
A control device as shown in FIG. 1 is provided.

In the figure, 36 is a tilt sensor. Although not shown in the figure, this sensor detects the inclination state by utilizing the fact that the surface of the water sealed in the U-shaped tube remains horizontal despite the inclination of the U-shaped tube. It is constructed with a tilt sensor that detects the following three states. The current sensor 36 is installed on the side of the machine such as a tractor so as to be rotatable in a vertical plane. Preferably, the rear wheel 10 (
It is installed directly above the axis shown in Figure 2). This is because the inclination of the aircraft body can be detected most accurately.

38 is a rack that moves as the hydraulic cylinder is driven, and 40 is a pinion that meshes with the rack.

The pinion 40 and the sensor 36 are connected via a power transmission mechanism 42 to feed back the amount of elevation of the working machine 14 by the hydraulic cylinder 22. In this case, the power transmission mechanism is a differential gear device, and regardless of the movement of the rack 38 by the hydraulic cylinder 22, the sensor 3
6 can be rotated to change the posture to a horizontal state.

The angular displacement of the position control lever 34 mentioned above is also input to the differential gear device 42 . This is because the hydraulic cylinder 22 and the rack 38 move in proportion to the angular displacement of the lever 34, and the inclination sensor 36 also inclines accordingly.

This is for initially setting the inclination sensor 36 to a horizontal state regardless of the installation height of the work implement 14.

44! The controller is a controller that receives and outputs any of various signals such as an output signal from the inclination sensor 36, such as forward inclination or backward inclination.

Reference numeral 46 denotes an electromagnetic valve which is operated in response to the output from the controller 44, and is used to control the elevation and the amount of elevation of the hydraulic cylinder 22.

Reference numeral 48 and 50 are switches for detecting the stroke end of the rack 38, and when the switch is activated, a signal is sent to the controller 44 so that the control device is not activated. The switch 48 is the one that generates Q, 20 pJ when the work a14 is raised to the upper limit when no work is performed by the work equipment 14, and the switch 50
is for setting the lower limit of the working machine to prevent overloading the working machine, etc., and turns ON when the working machine is lowered too much.

Therefore, when carrying out work using a tractor or the like, the plowing depth of the work implement 14 is first set by operating the position control lever 34. The displacement of the lever 34 causes the tilt sensor 36 to tilt, but since the power from the hydraulic cylinder 22, rack 38, and pinion 40 is transmitted via the differential gear 42, the tilt is canceled and the sensor 36 is tilted. It still remains horizontal.

Suppose, therefore, that there is a depression in the ground halfway through the work, and the front wheel 12 gets stuck in the depression, causing the rotary 14 to float a little higher. At this time, the tilt sensor 36 detects the forward tilt and sends a signal to the controller 44. The controller 44 moves the solenoid valve 46 to drive the hydraulic cylinder 22, thereby lowering the rotary 14 a little. Along with this, the movement of the rack 38 and pinion 40 attempts to return the inclination of the inclination sensor 36 to the horizontal state via the differential gear device 42. When the tilt sensor 36 detects the horizontal state around 1, the hydraulic cylinder 22, rack 38, etc. stop moving.

When the tractor returns to the horizontal position again, the tilt sensor 3
6 detects the opposite inclination, the rotary 14 is driven by the hydraulic cylinder 22 to rise slightly.

Effects of the Invention As described above, the present invention includes the hydraulic cylinder 22 that raises and lowers the working machine 14, and also includes the sensor 36 that detects changes in plowing depth of the working machine, and uses a signal from the sensor 36 to control the hydraulic cylinder 22. In an automatic plowing depth control device for a tractor, etc., which operates to correct changes in plowing depth due to the above-mentioned inclination, the sensor 36 is constituted by an inclination sensor that detects two states of forward inclination and backward inclination. A sensor 36 is installed on the side of the machine such as a tractor, and a rack 38 is provided that moves as the hydraulic cylinder 22 is driven, and a pinion 40 that meshes with the rack and the sensor 36 are connected to the rack when the hydraulic cylinder moves. However, since the above-mentioned sensor is connected by a power transmission mechanism 42 that can change its attitude to a horizontal state, there is no need to take the trouble to provide a rotary cover and install the sensor there, as in conventional control devices. There isn't. This is particularly effective when using a work machine that does not require a rotary cover.

Furthermore, since the sensor is configured with a tilt sensor 36 that detects three states: horizontal, forward tilt, and backward tilt, digital control can be performed. Therefore, it is possible to configure the controller 44 and the like at low cost.

Furthermore, in the conventional system, the amount of vertical adjustment of the work machine is detected using a potentiometer and feedhacked, but such a troublesome and expensive device can be made unnecessary.

Note that if a switch 48,50 is provided to detect the end of the stroke of the rack 38, the control device can be prevented from operating when the switch is activated, which is advantageous in increasing the safety of the control operation. It is.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a plowing depth control device according to the present invention. FIG. 2 is a front view of a tractor equipped with an effective plowing depth control device. 10... Rear wheel 12... Front wheel 14... Work equipment 16... Lower link 22... Hydraulic cylinder 26... Rondo 34... Position control lever 36...
・(Rotating angle sensor 38...Rack 40...Binion 42...Differential vJ gear device 44 ・ ・ ・Controller 46...Solenoid valve

Claims (1)

[Claims] It is equipped with a hydraulic cylinder (22) that raises and lowers the work implement (14) and a sensor (36) that detects changes in the plowing depth of the work implement, and the hydraulic cylinder is actuated by a signal from the sensor to change the plow depth due to the inclination. In an automatic plowing depth control device for a tractor or the like that corrects changes, the sensor is an inclination sensor (36) that detects two states of forward inclination and backward inclination.
In addition, the sensor is installed on the side of the machine such as a tractor, and a rack (38) is provided that moves with the drive of the hydraulic cylinder, and the pinion (40) that meshes with the rack and the sensor are installed as described above. The control device is characterized in that the sensor is connected by a power transmission mechanism (42) that can change the attitude of the sensor to a horizontal state regardless of the operation of the rack by a hydraulic cylinder.