JPS61254113A - Apparatus for controlling height of reaping part of combine - 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 Field of Application) The present invention relates to a device for automatically controlling the reaping section of a combine harvester to a predetermined height by raising or lowering it.

(Prior art and its problems) This type of height control of the reaping section is similar to general position control, in which the current height of the reaping section is detected, the output is fed back, and the target height is set. The elevating device of the reaping section is controlled so that the two match while comparing the output.
In recent years, ultrasonic distance sensors have been proposed as means for detecting the height of the reaping part in such cases (for example,
32!324 Publication).

Ultrasonic type sensors measure distance based on the reflection time of ultrasonic waves emitted toward the ground, and are non-contact sensors, so they are different from conventional grounding pieces that constantly slide into contact with the ground. Compared to the type (for example, Japanese Utility Model Application Publication No. 164234/1983), it has the advantage of being superior in durability with no wear or breakage of the detection part, and being able to detect wet fields with the same high precision as dry fields. On the other hand, if there are foreign objects such as straw in the ultrasonic transmission/reception path, the ultrasonic waves will reflect from them and cause noise, and if the transmission/reception path is shortened to prevent foreign objects from entering, the ultrasonic reflection time will be shortened. If it is too large, it also has the disadvantage of causing deterioration in accuracy.

It is an object of the present invention to eliminate the drawbacks of such an ultrasonic distance sensor and take advantage of its advantages to improve the accuracy of height control of the reaping section.

(Means for Solving the Problems) In order to achieve the above object, the present invention installs a transmitter/receiver of an ultrasonic distance sensor on the upper back side of the grass cover at the tip of the cutting rod in the reaping section, and the transmitter/receiver Extend the ultrasonic conduit connected downward so that its lower end opening faces the ground at the tip of the weeding rod.

(Function) The ultrasonic pulse transmitted from the transmitter/receiver passes through the ultrasonic conduit, exits from the lower end opening, reflects on the ground at the tip of the dividing rod, and is transmitted and received again via the lower end opening through the ultrasonic conduit. Return to the vessel.

Then, the distance between the reaping part and the ground, that is, the height of the reaping part, is detected from the time from sending this ultrasonic pulse until it returns, and this detection output is compared with the set output of the target height, and the cutting is started without control the height of the section.

(Example) Next, this will be explained with reference to the embodiments shown in the drawings.

1 is a reaping section connected to the main body 3 of the combine by a base shaft 2, and has a cutting rod 4, a cutting blade 5, a raking device 6, and a culm pulling device 7, and a hydraulic cylinder 8 connects the harvester to the main body 3 of the combine. Go up and down.

Then, a grass-dividing cover 10 is fixed to the tip of the grass-dividing rod 4 via a connecting plate 9, and an ultrasonic distance sensor transmitter/receiver 11 is attached to the upper rear surface of this cover 10, and connected to this 2. A wooden rubber ultrasonic conduit 12 is extended downward along the back side of the weeding cover 10, and its lower end opening faces the ground at the tip of the weeding rod 4.

The transmitter/receiver 11 may be one that serves both as a transmitter and a receiver, or may be an independent one.

FIG. 3 is a block diagram of an ultrasonic distance sensor in which a transmitting section 11a and a receiving section 11b are independent, 13 is a pulse generator, 14
is a gate, 15 is a clock oscillator, 1B is a counter, 1
Reference numeral 7 indicates an arithmetic unit, and 18 indicates an output unit.

However, when an ultrasonic pulse is transmitted from the transmitter 11a,
This passes through the ultrasonic wave conduit 12, hits the ground at the tip of the weeding rod from its lower end opening, is reflected, and returns to the receiving section 11b through the ultrasonic wave conduit 12 again. Then, at the same time as the ultrasonic pulse is transmitted, a gate pulse starts rising, and at the same time as the ultrasonic pulse is received, the gate pulse falls, and by counting the number of clock pulses included during that time, the time required for the ultrasonic wave to travel back and forth to the ground is determined. is converted into a distance and the output unit 18 outputs a resensor output.

This sensor output is fed back to a reaping section elevation control section (not shown) that drives the hydraulic cylinder 8, and the height of the reaping section 1 is controlled while being compared with a target height setting value.゛At that time, the reaping section 1 moves up and down using the base shaft 2 as a fulcrum, so the height of the tip of the divider rod farther from the base shaft 2 changes widely, and the distance between the lower end opening of the ultrasonic conduit 12 and the ground changes. The vertical movement of the reaping part l can be detected sharply.

Figure 5.6 shows another embodiment, with the weeding rod 4 and the weeding cover lO
The connecting plate 18 that connects the
The connecting plate 19 partitions the lower end openings of the left and right ultrasonic conduits 2o, 2o. Connecting plate 18
The length L of the protruding base of is set larger in consideration of the directivity of the ultrasonic pulse used. 21 is a detection body for controlling the direction of the combine harvester protruding from the left and right sides of the weeding cover lO,
If the lower end opening of the conduit 20 is located above the detection body 21, no water or mud will enter, and no soil clogging will occur.

In this embodiment, when the reaping section 1 is lowered and its bottom touches the ground, the bottom of the connecting plate 19 is buried in the ground and the left and right conduits 20.
20 and prevents the reflected waves of the ultrasonic pulses from reaching the receiver, it is possible to quickly detect the grounding of the reaping section, which prevents the reaping section 1 from being lowered too low and falling into the ground, causing damage. Accidents can be prevented.

(Effects of the Invention) As described above, in the present invention, the transmitter/receiver 11 of the ultrasonic distance sensor for detecting the height of the reaping section in the reaping section height control device
is attached to the upper rear surface of the grass dividing cover 10 to detect the height of the cutting section 1 at the tip of the cutting rod where the height changes are large, so that the elevation of the cutting section 1 using the base shaft 2 as a fulcrum can be accurately controlled. Furthermore, since the distance between the transmitter/receiver 11 and the ground is long, the reflection time of the ultrasonic waves is long, and there is little overlap between the transmitted and received waves, making it possible to receive them clearly and accurately measure the distance.Furthermore, since the ultrasonic waves are transmitted and received via an ultrahigh frequency conduit, This has the effect that foreign objects such as straw are less likely to enter the transmission/reception path and cause noise, and the accuracy of the sensor is improved.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional side view of the main parts of the reaping section in which the present invention is implemented, Fig. 2 is a rear view thereof, Fig. 3 is a block diagram of the ultrasonic distance sensor, and Fig. 4 is an overall side view of the combine harvester. 5 is a side view of a main part of a reaping section in another embodiment of the present invention, and FIG. 6 is a front view with the grass cover of FIG. 5 removed. 4 is a dividing rod, 10 is a dividing cover, 11 is a transmitter/receiver, 12
．． 20 is an ultrasonic conduit. Patent applicant: Iseki Agricultural Machinery Co., Ltd. Agent Tobe Maki (and 2 others) Figure 1 Figure 2

Claims (1)

[Claims] An ultrasonic distance sensor transmitter/receiver that detects the height of the cutting section from the ground is attached to the back of the upper part of the weed cover at the tip of the weeding rod, and an ultrasonic conduit connected to the transmitter/receiver is extended downward. A reaping section height control device for a combine harvester, characterized in that the lower end opening faces the ground at the tip of the dividing rod.