JPS60259105A - Earth height controller of working part in agricultural machine - 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] [Industrial Application Field] The present invention provides a working section that is connected to the machine so that it can be raised and lowered, from the time when ultrasonic waves are periodically transmitted toward the ground. The height of the work part above the ground is detected based on the length of time it takes to receive the reflected wave, and based on this, the work part is automatically raised and lowered so that the height of the work part above the ground is maintained within the set range. The present invention relates to an automatic ground height control device for agricultural machinery, which is equipped with a mechanism for controlling the height of agricultural machinery.

[Conventional technology]

To detect the height of the working part above the ground, a mechanical sensor is pointed at the field and the sensing part is pressed, the height above the ground is determined based on the detection result, and the lifting and lowering of the working part is controlled based on the result. was.

[Problem that the invention seeks to solve]

In the case of the above method, the height above the ground is detected using a mechanical contact sensor, so in areas where the field is soft, the sensor sinks into the soil and becomes unable to detect the height above the ground. Even if you are relaxing or in a hard field, there is no problem when the aircraft is moving straight and detecting the height above the ground, but when the aircraft rotates, the base supporting the sensor may be twisted due to the rotation. There was a big problem in practical use because there was a high risk of damaging the sensor.

Therefore, we devised a method to non-contactly detect the height above the ground based on the time between transmitting and receiving ultrasonic waves, but because it is non-contact, conventional contact-type sensors that mechanically press against the field would not be able to crush it. If the height of the working part above the ground is controlled based on the detection results of small irregularities or straw debris in the field, there is a risk that the working part will move up and down unnecessarily.

The present invention has been made in view of the above points, and its purpose is to provide a non-contact method for detecting the height above the ground of a working part in a non-contact manner and at a value suitable for the actual situation. The point is to provide a control device.

[Means for solving the problem] The detection means of the height above the ground detecting device according to the present invention averages a plurality of non-contact detection results and raises or lowers the height above the ground of the working part based on the average. Its functions and effects are as follows.

[For production]

In other words, as the machine advances, ultrasonic waves are emitted at predetermined intervals, multiple times are memorized until the reflected waves from the field are received, and the height of the working section above the ground is determined based on the average value. This is intended to control the elevation so that it is within the set range.

〔Effect of the invention〕

Therefore, when the height of the work part above the ground is detected by ultrasonic waves, even if there is a small variation in the detected value due to extremely small irregularities or straw waste, the value is immediately returned to the same value in order to be averaged. It now controls the lifting and lowering of the working part, allowing for more stable control while maintaining the strength of non-contact sensors, which can be used in any field.

〔Example〕

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the details of the application of the present invention to a cutting height control device for a combine harvester, which is an example of an agricultural working machine, will be explained based on illustrative drawings.

As shown in Figure 1, a pair of left and right crawler traveling devices (1
), (1) and this machine (3) equipped with a threshing device (2)
A pair of left and right pulling devices (4), (4),
A clipper-type reaping device (5) and a reaping work section (8) equipped with a device (7) for conveying and supplying the cut husk to the feed chain (6) of the threshing device (2) are arranged in series so as to be able to rise and fall freely. At the same time, the reaping frame (9) of the reaping work section (8) and the book 1! A hydraulic cylinder (11) for driving and raising and lowering this working part (8) is interposed between it and the machine frame (10) of (3) to form a combine and harvester.

In addition, as shown in FIGS. 2 and 3, the working section (8)
The working part (8
) is provided with a sensor (12) for detecting the cutting height (height above ground) of
a mechanism (14) that automatically controls the lifting and lowering of the working part (8) so that the cutting height is maintained within a set range based on an average value of the working part (8);
In addition, a control mechanism (16) is provided which can selectively switch between the two control mechanisms (14) and (15) by operating a switch.

The sensor (12) includes an ultrasonic ceramic microphone (17) and an ultrasonic wave (a) as shown in FIG.
) toward the field scene on the mowed field side at set time intervals (Δt) at every set time (tl), and an ultrasonic transmitter (12A) consisting of a transmitting circuit (18) that emits waves reflected from the field scene. (b
) and an ultrasonic receiver (12B) consisting of an ultrasonic ceramic microphone (19) that receives sound waves from the microphone (19) and a receiving circuit (20) that amplifies the sound waves received from the microphone (19).
are arranged in one case (21) fixed to the back of the triggering device (4), and the transmitter (1)
The time (t2) required from transmitting the ultrasonic wave from 2^) to receiving the reflected wave at the receiver (12B) is measured, and from this the height above the ground of the reaping part (8), that is, a mechanism (2) that calculates the cutting height and inputs it to the calculation mechanism (13);
2).

The automatic cutting height control mechanism (14) includes the calculation mechanism (1
A setting device (2) that allows you to change the average value from 3) and the desired cutting height.
3) and the solenoid of the control pulp (24) for the hydraulic cylinder (11) so that the calculated detected value is maintained within the allowable range of the set value based on the comparison result. (24a), (24
b) is comprised of a control section (25) that automatically controls the operation.

The manual cutting height control mechanism (15) includes a switch (26) for operating the ascending solenoid (24a) of the control valve (24) and a descending solenoid (24b).
It consists of a switch (27) for operating the switch.

Therefore, as shown in FIGS. 3 and 5, the sensor (
It is determined whether the detected value from the cutting height measuring mechanism (22) of (12) is normal or not, and if it is normal, the detected value (
A mechanism (28) that inputs h) as it is to the calculation mechanism (13), and if it is abnormal, replaces the abnormality detection value (h') with the immediately previous detection value and inputs it to the calculation mechanism (13). has been established.

In addition, as a means for calculating the average value of multiple detection values, as shown in FIG. Alternatively, the average value may be calculated while all stored detected values are deleted and new detected values are sequentially stored.

Also, a mechanism (29) that enlarges the width of the fuwawa band (B) for the ultrasonic waves received by the receiver (12B) than usual.
Then, based on the information from the transmitting circuit (I8), it is detected whether the microphone (17) is in the transmitting state or not, and when the microphone (17) is in the transmitting state, the set time for transmitting from now on is detected. A timer circuit (3) that automatically operates the dead zone medium enlargement mechanism (29) by (Δt)
o) and a control check mechanism (31) that disables the automatic cutting height control of the working part (8) for the set time (△ also) after the transmitter (12^) enters the transmitting state. It consists of When such a control and check mechanism (31) is provided, the transmitted vibration (c) of the transmitter (12A) is transmitted to the case (21).
Even if the vibration is propagated to the receiver (12B) through the vibration, the mowing height of the working part (8) will not be inappropriately controlled based on this vibration, and the mowing height control can be stabilized.

[BRIEF DESCRIPTION OF THE DRAWINGS] The drawings show an embodiment of the device for controlling the height above the ground of a working part in an agricultural machine according to the present invention, and FIG. 1 is a side view of the front part of a combine harvester, and FIG. 2 is a partially cutaway front view. , Fig. 3 is a block diagram showing the cutting height control system, Fig. 4 ((), (o) is an explanatory diagram showing the ultrasonic transmission state and reception state, and Fig. 5 shows the normal detection value and abnormality detection. This is an explanatory diagram of the values. (3)...This machine, (8)...Working department. Patent attorney Osamu Kitamura

Claims (1)

[Claims] ■ A working section (
8) is provided with a means for detecting the height of the working part above the ground based on the length of time from the time of transmission of ultrasonic waves that are periodically transmitted towards the ground until the reception of the reflected waves, and the detection result is Based on the results, work section (8) (
7) A height control device for a working part above the ground in an agricultural machine, characterized in that a means is provided for automatically controlling the elevation of the working part (8) so that the height above the ground is constant. (2) The ground height control device according to claim 0, wherein the next average of the detection results after calculating the average of a plurality of detection results is to calculate the average of a new plurality of detection results. (2) The height control device above the ground according to claim 0, wherein the average of the detection results is a moving average in which the stored detection value is shifted by one at each detection.