JPH0126163Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to the improvement of a device for detecting the height above the ground of a working part in agricultural work. To provide a device that can always adjust the cutting height in the vertical direction and accurately detect the cutting height regardless of the height changing operation.

By the way, a combine harvester generally has a structure as shown in FIG. In addition, the reaping section 4 is provided with a grass divider 5, a pulling device 6, a cutting blade 7, etc., and a control section 8 is provided on the machine body 1, and a transmission that hangs down from the control section 8 is provided. While power is input to the crawler traveling device 2 through the case 9, the reaping section 4 is provided inside the machine body 1.
There is built-in means for threshing and sorting the harvested crops supplied by a conveyor (not shown).

In such a combine harvester, when adjusting the cutting height of crops by the cutting blade 7 up and down, the support arm 3
is rotated by a hydraulic cylinder (not shown) around the pivot end on the side of the machine body 1 to raise and lower the entire cutting section 4. However, when changing the cutting height, the ground height of the cutting blade relative to the field surface must be precisely adjusted. In order to set the setting, a cutting height detection sensor 10 using ultrasonic waves or radio waves (more specifically, a distance to the ground detection sensor) 10 is attached to the back side of the grass divider 5 as shown in the drawing of the reaping unit 4, and the distance to the ground is determined by the sensor 10. Using the detection output, the cutting blade 7 can be automatically controlled to maintain the set height above the ground according to the undulations of the field surface, or the height above the ground of the cutting blade can be set to the desired cutting height according to the above output. Efforts have been made to do so. However, in order to change the cutting height, the reaping section 4
1, the orientation of the cutting height detection sensor 10 with respect to the field surface changes as is clear from the comparison between the solid line posture and the virtual line posture in FIG. The problem is that the radio waves do not hit the field surface vertically, so it is impossible to accurately detect the distance to the ground, making it impossible to precisely maintain or set the cutting height.

The purpose of the present invention is to eliminate such difficulties, and to achieve this goal, an angle correction means reads out the amount of vertical movement of the working part of an agricultural machine and constantly corrects the direction of the detection sensor vertically downward to follow the movement. The aim is to achieve this by:

Hereinafter, details of the present invention will be explained using the embodiment drawings of FIGS. 1 to 3 showing a combine harvester. still,
In the structure of this embodiment, the same components as those in FIG. 4 are denoted by the same reference numerals, and the explanation thereof will be omitted.

In FIG. 1, a mounting bracket 12 is fixedly installed on the back side of the grass divider 5, and a cutting height detection sensor 1 is connected to the bracket 12 via a horizontal horizontal shaft 13.
0 is suspended freely to rotate around the horizontal horizontal axis 13, and a tension spring 14 is attached between the mowing height detection sensor 10 and the weed divider 5, so that the sensor 10 is constantly While being biased toward the divider 5 side, on the body 1 side, the end boss portion 3a of the support arm 3 is rotatably fitted onto the support shaft 11, and a fixed tongue piece 15 is protruded from the support shaft 11. At the same time, the fixed tongue piece 15 and the cutting height detection sensor 1
A rope body 16 such as a wire is stretched between the rope body 16 and the mowing height detection sensor 10 using the tension of the rope body 16 and against the spring force of the tension spring 14. The posture is maintained as if facing each other.

Therefore, the hydraulic cylinder 18 interposed between the support arm 3 and the required frame 17 on the machine body 1 side is extended, the support arm 3 is rotated around the support shaft 11, and the reaping section is moved from the solid line position to the imaginary line. Even when the shaft 11 is raised to the position, the shaft 11 is fixed to the support member 19 and does not rotate, and the shaft 11 and the cutting height detection sensor 10
The distance from the mowing height detection sensor 10 is constant regardless of the rise due to the circumferential movement of the mowing section, and the length of the cable body 16 is also constant.
The sensor 10 is always maintained in a vertical position by the balance between the tension of the cable body 16 and the spring force of the tension spring 14 resisting the tension. In other words, the grass divider 5
The mowing height sensor 10 is relatively rotated in the opposite direction around the horizontal horizontal axis 13 by the angle at which the mowing height sensor 10 rises and its inclination changes, and the angle is corrected so that it is in a vertical position. Therefore, because of the presence of the angle correction means A including the components 11 to 16, the cutting height detection sensor 10 always emits ultrasonic waves or radio waves from the vertical direction to the field surface to detect an accurate ground distance and output it. It comes to that.

Although FIG. 1 shows a mechanical angle correction means A using a drag body 16, there is no problem in replacing this with an electrical angle correction means as shown in FIG. In the figure, the boss portion 3 of the support arm 3
A gear 20 is formed on the outer periphery of a, and a gear 21 meshing with this gear 20 is a potentiometer 2.
It is fixed to the input shaft 23 of No. 2. Further, a cutting height detection sensor 10 is fixed to an output shaft 25 of a step motor (or servo motor) 24. When the support arm 3 rotates, a rotational force corresponding to the amount of rotation is extracted by the meshing rotation of the gears 20 and 21 and inputted to the potentiometer 22, which corresponds to the rotational force of the meter 22. code voltage 2
6 to the step motor 23, the motor 24 is rotated by a required angle in a direction to maintain the vertical posture of the cutting height detection sensor 10, and angle correction is performed.

In addition, in the case of the cutting height detection sensor 10 used in this way, the emitted ultrasonic waves or radio waves must reliably hit the surface of the field, and when they hit the base of the grain culm and are reflected, the accurate distance to the ground can be measured. I can't. Therefore, as shown in FIG. 3, at least the transmitter 10a of the cutting height detection sensor 10
It is preferable to install the mounting bracket 12 shown in Fig. 1 within the width of the cutting.This will prevent the ultrasonic waves or radio waves from hitting the base of the grain culm and being reflected, thereby reducing the reception of the waves. The detected value of the device 10b represents the accurate ground distance.

The present invention is as described above, and because of the presence of the angle correction means, the height above ground detection sensor can always be oriented perpendicular to the field surface and the accurate distance above the ground to the field surface can be detected regardless of the vertical position movement of the working part. ,
It has the advantage of being able to precisely maintain or set the height of the working section to reap crops and perform various other agricultural tasks.

[Brief explanation of the drawing]

Fig. 1 is a schematic side view showing one embodiment of the cutting height detection device according to the present invention, Fig. 2 is a schematic side view showing the configuration of another embodiment, and Fig. 3 is a preferred mounting position of the detection sensor. FIG. 4 is a front view of the cutting section and a schematic side view of the combine harvester for explaining the drawbacks of the conventional cutting height detection device. 1... Airframe, 4... Working part, 10... Ground height detection sensor, A... Angle correction means.

Claims (1)

[Scope of utility model registration request] When the machine is equipped with a working part that can be moved up and down, and this working part is equipped with a height detection sensor above the ground, the amount of vertical movement of the working part is read out, and the direction of the detection sensor is always adjusted vertically downward to follow the movement. A height-to-ground detection device for an agricultural machine, which is provided with an angle correction means for correcting the angle.