JPH0616653B2 - Airframe height detector for paddy work machines - Google Patents

Description

The present invention relates to a paddy working machine represented by a rice transplanter, and more particularly to a device for detecting the height from a mud surface to a body.

[Conventional technology]

For example, in a riding type rice transplanter, the height from the paddy field to the seedling planting device is detected by a grounding float, and the seedling planting device is automatically moved up and down so as to keep the set height from the paddy field. This ensures that the planting depth of seedlings is kept constant.

With the above-mentioned ground float type, the height from the surface of the paddy field to the seedling planting device is detected, and the seedlings are planted at the set depth from the surface of the paddy field. On the other hand, in paddy fields where the amount of water is relatively large, the surface mud may be too soft for planting seedlings, and thus the above-mentioned ground float type has a risk of tipping after planting.

Therefore, in recent years, research has been conducted on a device that is located below the surface of the paddy field and has a suitable hardness for planting seedlings, and detects the height from this mud surface to the seedling planting device. There is a device having the following configuration as an example of this device.

In other words, a pressure-sensitive sensor that is repeatedly driven in a fixed cycle is provided for a posture that plunges into the mud surface and a reference posture that is located above the mud surface, and the pressure-sensitive sensor plunges into the paddy field from the reference posture to set the set hardness. This is a configuration for measuring the elapsed time until the mud surface is detected.

[Problems to be solved by the invention]

When the pressure sensor passes through the mud, the resistance of the mud acting on the pressure sensor electrically detects the hardness of the mud, so the detection sensitivity is set to be extremely sensitive. ing. Therefore, a lot of disturbances may be picked up during the time from the reference posture to the plunge into the surface of the paddy field, and the position of the mud having the set hardness may not be accurately detected.

In view of the above-mentioned problems, the present invention has an object to configure so that the position of the mud having the set hardness can be accurately detected by the pressure sensitive sensor.

[Means for solving problems]

The feature of the present invention is that in the body height detection device for a paddy work machine as described above, the signal from the pressure sensitive sensor is not taken in only during the set time in the process from the reference posture to the time of entering the mud surface. The means is provided in the detection circuit, and its operation and effect are as follows.

[Action]

With the configuration as described above, various unnecessary disturbances detected by the pressure-sensitive sensor from the reference posture of the pressure-sensitive sensor to the time of plunging into the mud surface are deleted, and the pressure-sensitive sensor is positioned in the reference posture. It is possible to accurately recognize the time when the pressure sensor is operated and the time when the pressure sensitive sensor is located on the mud surface having a predetermined hardness.

〔The invention's effect〕

Therefore, it becomes possible to accurately measure the elapsed time from the time when the pressure sensor is located in the reference posture to the time when it is located on the mud surface having the predetermined hardness, and the height from the mud surface having the predetermined hardness to the airframe is measured. The accuracy of detection is improved.

〔Example〕

Hereinafter, a riding type rice transplanter, which is one of the embodiments of the present invention, will be described with reference to the drawings.

As shown in Fig. 1, the planting mission case (1) is provided with a rotatively driven planting arm (2) at the rear, and the planting mission (1) has a guide rail (3) above the seedling stand.
The seedling planting device is configured by sliding (4) in the left-right direction. The seedling planting device is vertically movably connected to a traveling machine body (not shown) via a four-link mechanism (5) to form a riding type rice transplanter, which is one of the paddy field working machines.

The end of the planting arm (2) is provided with a fixed type planting claw (6) and a push-out type push-out part (7), and the tip of the planting claw (6) is shown by a dashed line in the same figure. Follow the path like this, seedling stand (4)
The seedlings above are cut out and planted. The planted nail
A non-compressible working fluid is enclosed in the base of (6) and a pressure sensitive sensor that senses pressure fluctuations of this working fluid.
The piezoelectric element as (8) is attached, and this piezoelectric element (8)
The signal from is sent to the control device (9). Further, the rotation sensor (10) for detecting the rotation phase of the planting arm (2) is provided at the base part where the planting arm (2) is driven to rotate.
(Rotary encoder) is attached to the control device.
It is connected to (9).

With the above configuration, when the tip of the planting claw (6) passes the reference point (A) of the passage trajectory, a large resistance when cutting out the seedlings acts on the planting claw (6). As shown in the figure, a very large signal (A ') is input. And this signal (A ')
Is recognized as corresponding to the reference point (A) based on the phase angle from the rotation sensor (10). After that, when the tip of the planting claw (6) passes the detection point (B) on the surface (S) of the paddy field, and the mud surface (G) with the set hardness that is the standard for planting.
When passing through the detection point (C) of
(B ') and (C') are input, and signals are also input to the control device (9) at other rotation phases, but the signal (A ') corresponding to the reference point (A) is The signal from the piezoelectric element (8) is ignored for a set time (t) after input, and the planting claw (6) rushes into the surface (S) of the paddy field after the set time (t). Then, the so-called noise is cut.

Then, by measuring the time (t ') from the input time of the signal (A') when passing the reference point (A) to the input of the signal (C ') corresponding to the set mud hardness, The height from the mud surface (G) to the seedling planting device is calculated, and if the detected height is out of the set height, the control valve (12) of the hydraulic cylinder (11) that raises and lowers the four-link mechanism (5) is operated. ), An operation signal is issued from the control device (9), and the height from the mud surface (G) to the seedling planting device is corrected to the set height. This detection operation is
The planting claw (6) finishes planting one seedling after passing the reference point (A), and is repeated at a constant cycle (T) until it passes the reference point (A) again. .

The set time (t) to ignore the signal from the piezoelectric element (8)
Is set to a short time at the beginning of work, and the first signal
After the time (t ') from (A') to the signal (C ') is detected, the set time (t) is lengthened based on this time (t'), and immediately after the set time (t) elapses. The signals (B ') and (C') are input to the. After that, the time (t ')
The length of the set time (t) is also changed in accordance with the change in the length of.

It should be noted that reference numerals are added to the claims for convenience of reference to the drawings, but the present invention is not limited to the structures of the accompanying drawings by the entry.

[Brief description of drawings]

The drawings show an embodiment of a body height detecting device for a paddy working machine according to the present invention. Fig. 1 is a side view of a seedling planting device equipped with a pressure-sensitive sensor, and Fig. 2 is a signal from the pressure-sensitive sensor. It is a figure which shows a detection state. (8) …… Pressure sensor, (T) …… constant cycle, (t) …… set time.

Claims (1)

[Claims] 1. A pressure-sensitive sensor (8), which is repeatedly driven at a constant cycle (T) in a posture of thrusting into the mud surface and a reference posture positioned above the mud surface, is provided at a body fixing portion, and the pressure-sensitive sensor is provided. It is configured to detect the height of the aircraft against a mud surface with a predetermined hardness by measuring the elapsed time from the reference attitude of the sensor (8) to the time when the signal from the pressure sensitive sensor (8) exceeds the set value. A device for detecting the height of a paddy working machine, which receives a signal from the pressure sensor (8) for a set time (t) during the process from the reference posture to the time of entering the mud surface. A device for detecting the height of a paddy field machine, which has a non-existing means in the detection circuit.