JPH0116123B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides automatic elevation control based on the sampling value of the height above ground detection result measured by a height above ground detection sensor and sampled at every predetermined time every predetermined number of sampling times. The present invention relates to an agricultural machine equipped with a working device.

Conventionally, the height above the ground is measured by a height above the ground sensor such as an ultrasonic sensor installed in the working device, and the height above the ground is sampled a predetermined number of times. A means for automatically raising and lowering the height above the ground to maintain a constant height above the ground is adopted.

However, averaging based on the measured values themselves by such means increases the influence of abnormal values due to measurement errors, so in some cases, the work equipment may be raised or lowered unnecessarily, making it difficult to perform stable elevation control. The drawback is that it cannot be done.

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to always perform stable elevation control without being affected by the measured value of the height above the ground that is erroneously detected as abnormally high. Our goal is to provide agricultural machinery that is capable of

In order to achieve the above-mentioned object, the agricultural machine according to the present invention provides an abnormal value area in which the detected height above the ground is previously divided into an abnormal value area having a height higher than a predetermined value, and each height area of a normal value area which is divided into a plurality of height areas below the abnormal value area. If the ratio of the number of sampling values belonging to the abnormal value region to the predetermined number of sampling times is greater than or equal to a predetermined value, the lifting control of the work equipment is prohibited, and the control of the abnormal value is If the ratio is less than the predetermined value, the elevation control is performed in accordance with the height region in which the number of sampled values in the normal value region is the largest.

Due to the above characteristic structure, the following excellent effects have been achieved.

In other words, the measured value measured by the sensor is sampled a predetermined number of times as a representative value corresponding to the height range of a predetermined area that is divided into multiple areas including the abnormal value area, and a normal sampling value that reliably excludes the abnormal value is obtained. In addition, if many abnormal values are detected, the lifting control of the work equipment is not performed based on only the abnormal values, so the influence of abnormal value detection can be reliably removed, and malfunctions due to abnormal values can be reliably prevented. We were able to prevent this from happening.

In addition, the lift control is not performed based on a simple averaged value of the sampling values, but is performed in accordance with the height area to which the most detected normal sampling values belong, so it is more accurate to the actual situation. Accurate and stable elevating and lowering control can be performed according to the situation, and malfunctions such as unnecessary elevating and lowering of the work equipment can be reliably prevented.

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, a pulling device 2, a cutting blade 3,
A reaping section 1 as a working device consisting of a conveying device 4 is provided at the front part of a traveling vehicle body equipped with a crawler traveling device 5 so that it can swing up and down by expanding and contracting a hydraulic cylinder 6 as an actuator, and is used as an agricultural working machine. A combine has been configured.

A weeding tool 7 is provided in front of the pulling device 2, and each of the weeding tools 7 is fixed to the support frame 8 of the reaping section 1 at the back thereof. An ultrasonic sensor 9 is attached to the support frame 8 to measure the height above the ground.

The ultrasonic sensor 9 consists of an oscillator 10 that emits ultrasonic waves towards the ground and a receiver 11 that receives the reflected waves. ,
It is configured to measure the height of the reaping section 1 above the ground.

Hereinafter, a system for measuring the height above the ground by the ultrasonic sensor 9 and controlling the elevation based on the measurement results will be explained with reference to FIGS. 2 to 4.

As shown in FIG. 2, the control device 12 includes an input/output interface 13 and a CPU as an arithmetic device.
14, a timer 15, a counter 16, and a memory 17, and is configured to function as a so-called microcomputer, and basically operates the hydraulic cylinder 6 based on the measurement result of the height above the ground by the ultrasonic sensor 9. The electromagnetic valve 18 is driven to control the height of the cutting section 1 above the ground to maintain it within a desired range, thereby making the cutting height constant.

The measurement of height above ground will be explained below.

The oscillator 10 of the ultrasonic sensor 9 intermittently emits ultrasonic waves toward the ground according to the timing signal _P1 outputted via the input/output interface 13 at predetermined periodic intervals preset by the timer 15, At the same time, counter 16 is activated.

When the reflected wave is received by the receiver 11 and the received signal P ₂ is input to the control device 12, the counter 16 is stopped, and when the ultrasonic wave is transmitted, the counter 16 is stopped.
The count value of the counter 16 started at t ₁ and stopped at t ₂ at the time of this reception is measured as the ground distance TH.

After that, it is determined which preset height area above the ground the measured distance TH belongs to, and the measurement is repeated using the representative value as the sampling value SD(i) until the predetermined number of measurements ic is reached, and the result is The information is sequentially stored in the memory 17.

That is, as shown in FIG.
The TH is divided into four levels: an abnormal value area SD ₃ and three normal value areas SD ₂ , SD ₁ , and SD ₀ , and the boundaries of each area TH ₃ , TH ₂ , TH ₁ and the measurement Comparing the distance TH, the area SD of the four stages _{is 0}
~ SD ₃ are sampled as representative values.

After repeating the sampling of the height above the ground ic times, the numbers n ₀ to n ₃ of sampling values SD(i) belonging to each of the regions SD ₀ to _{SD 3} are calculated, respectively.

Next, check the ratio M of the number of samples n ₃ belonging to the abnormal value area SD ₃ to the total number of samples ic, and if this ratio M is a predetermined value M ₀ or more (for example, 90% or more), the ground height The current height above the ground is maintained by stopping the driving of the solenoid valve 18 in order to prohibit the elevation control of the reaping section 1 until the ratio M falls below a predetermined value _M0 . Let it happen.

Incidentally, when it is detected that the measurement ratio M of the abnormal value becomes equal to or higher than the predetermined value _M0 for the first time, the timer 15 monitors the subsequent time passage, and the ratio M remains unchanged even after the elapse of the predetermined time T. If the predetermined value M ₀ or more is exceeded, the alarm device 19 is activated to notify the operator that the control system is abnormal.

On the other hand, the measurement ratio M of the abnormal values is a predetermined ratio M ₀
If it is less than the normal value region SD ₀ to SD ₂ , calculate the maximum value N of the number of samples n ₀ to n ₂ belonging to each region within the normal value region SD 0 to SD 2, and calculate the ratio M′ of this maximum value N to the sampling number of all normal values. Only when the predetermined ratio M ₁ or more (for example, 50% or more) with respect to the number n ₀ + n ₁ + n ₃ , the area to which the maximum value N belongs SD ₀ , SD ₁ , SD ₂
The electromagnetic valve 18 is driven in order to control the raising and lowering of the reaping section 1 in response to this.

Note that the ratio M' of the maximum value N to the total number of samples may be adopted.

That is, the intermediate region between the normal value regions SD ₀ to _{SD 2}
Define SD ₁ as the normal appropriate ground height range, and this area
If the distance TH is measured the most in the areas SD ₂ and SD ₀ above and below SD 1, respectively, the reaping unit ₁ is controlled to descend or rise to reach the appropriate height area SD _1. maintain the height above the ground,
This ensures that the cutting height is constant.

By the way, in the above IC sampling, memory 1
The sampling value SD(i) stored in 7 is block transferred to replace the latter half (ic/2) with the first half sampling value SD (0 to ic-1/2), and the above ground height is The measurement is performed so that half of the sampling values overlap when sampling IC times.

In other words, the ratio check of the area SD ₀ to _{SD 3} to which the second and subsequent sampling values SD(i) belong is configured to be performed every ic/2 measurements of the height above the ground. The control response is stabilized by preventing the elevator control from responding to fluctuations in height.

Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of drawings]

The drawings show an embodiment of the agricultural machine according to the present invention,
Figure 1 is a front side view of the combine, Figure 2 is a block diagram of the control system, Figure 3 is an explanatory diagram of ground height sampling, and Figure 4 is a flowchart showing the operation of the control device. . 1... Work device, 9... Ground height detection sensor, 12... Elevation control device.

Claims (1)

[Scope of Claims] 1. A working device that is automatically controlled to raise and lower based on the sampling value of the height above ground detection result measured by the height above ground detection sensor 9 and sampled at every predetermined time every predetermined number of sampling times. The detected height above the ground is set as a representative value corresponding to each height region of an abnormal value region having a height higher than a predetermined value and a normal value region divided into a plurality of regions below the abnormal value region. If the ratio of the number of sampling values belonging to the abnormal value region and the predetermined number of sampling times is greater than or equal to a predetermined value, the lifting control of the working device 1 is prohibited, and the ratio of the abnormal values is less than the predetermined value. In the case of , the agricultural machine is configured to perform the lifting/lowering control in accordance with the height area in which the number of sampling values in the normal value area is the largest. 2 If the ratio of the abnormal values is less than the predetermined value, the number of sampling values belonging to the height region with the largest number of sampling values in the normal value region is relative to the number of sampling values belonging to the entire normal value region. 2. The agricultural machine according to claim 1, wherein the agricultural machine is configured to perform the elevation control in accordance with the height range only when the height range is equal to or higher than a predetermined ratio. 3. The agricultural machine according to claim 1 or 2, which is configured to issue an alarm if an abnormal value equal to or higher than the predetermined ratio is continuously measured for a predetermined period of time or more.