JPH0260286B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a lifting control device for agricultural machinery for paddy fields, and there are walking and riding types as rice transplanters and direct sowing seeders. Due to the need to keep the depth constant,
In the former walking type, the propulsion wheels are controlled to raise and lower according to the depth of the tiller, while in the riding type, a mechanism for raising and lowering the work equipment, such as a lifting link mechanism on the towing vehicle body, is adjusted to the depth of the tiller. It controls the elevation and descent.

However, in the conventional method of controlling the elevation of agricultural machinery based solely on the depth of the tiller, the degree of detection of the depth of the tiller fluctuates depending on the water depth of the paddy field, leading to false detections and accurate automatic control.

This invention has taken the following technical means for the purpose of solving the above-mentioned drawbacks.

That is, a detection body 16 (center float) for detecting the depth of the tiller is provided on the machine frame 13 (planting mission case) of an agricultural machine for paddy fields, and this detection body 16
An automatic lifting control mechanism is provided to control the lifting and lowering so that the machine frame 13 is maintained at a substantially constant height from the surface of the rice field, and a water depth detector 30 is provided to adjust the detection sensitivity of the detector 16 to the water depth of the rice field. The elevation control device for a paddy field agricultural machine is provided with a detection sensitivity adjustment device 25 that automatically adjusts the detection sensitivity to be insensitive when the water is deep and to be sensitive when the water is shallow using a spherical float.

To explain a riding-type rice transplanter which is an embodiment of the present invention, 1 is a towing vehicle body;
is the front wheel, 3 is the rear wheel for propulsion, 4 is the handle,
5 is the pilot seat.

Reference numeral 6 denotes a pair of left and right chain cases that are part of the vehicle body 1, and the rear wheels 3 are mounted on the rear ends of these chain cases. Post 8 is installed.

9 is a lifting link, an upper link 9a and a lower link 9
b and a rear vertical link 9c, the bases of both the upper and lower links 9a, 9b are pivotally connected to the support column 8, and the rear ends are pivotally connected by the vertical link 9c.

10 is a hydraulic cylinder device, cylinder 10
The base of the piston 1 is pivotally connected to the transmission case which is a part of the vehicle body 1, and the piston 10b side is connected to the arm 11 integrated with the upper link 9a.
When 0b protrudes, the rear part of the elevating link 9 is swung up.

12 is a rice transplanter as an agricultural machine. Reference numeral 13 denotes a machine frame, which is a planting transmission case in the illustrated example, and the vertical link 9 of the elevating link 9 is located between the left and right front ends of the machine frame.
It is attached to C so that it can be rolled freely. 14 is a seedling tank, and 15 is a seedling planting rod. The seedling tank 14 is supported on the planting mechanism case 13 so as to be able to reciprocate from side to side, and the seedling planting rod 15 is divided into left and right sides and extends rearward. The planting mechanism case 13 is provided at the rear end of the planting case 13 so as to be movable by a crank and a swing arm, and is provided so as to separate the seedlings from the seedling tank 14 and plant them therein.

Reference numeral 16 denotes a center float which is an example of a detector for detecting the depth of the tiller, and its rear part is pivotally attached to the lower part of the planting mission case 13 with a pin 17, and its front part is provided so as to be freely movable up and down.

Reference numeral 18 denotes a bracket, which is a flat metal fitting attached to the front part of the planting mission case 13.

Reference numeral 19 denotes a hydraulic switching valve, the valve body 19a side of which is pivotally connected to the bracket 18 with a pin 20, and the spool 19b side connected to the front part of the center float 16, which is a detection body, via a metal fitting 21 and a pin 22. . This hydraulic valve 19 is piped to the hydraulic cylinder device 10 in the hydraulic circuit shown in FIG. 5, and when the central float 16 moves upward, the piston 1
It is configured to project 0b and retract when moved downward.

Reference numeral 23 is an expansion/contraction link, and a pin 24 connects a float 16 side link 23a whose one end is pivotally connected to the pin 22 for attaching the float, and a bracket side link 23b whose upper and lower intermediate portions are pivotally connected to the pin 20 on the bracket 18 side. It has a dogleg shape when viewed from the side.

25 is a detection sensitivity adjustment device, in this embodiment,
A bracket 2 is attached to the front end of the central float 16.
A spherical float 30 as a water depth detector is provided via an arm 29 to a cylinder 28 which is rotatably attached to a cylinder 28 by a support shaft 27 and a protruding arm 31 projecting upward and a bracket side link 23.
A spring 32 is interposed between the upper part of the hydraulic valve 19 and the spool 19b of the hydraulic valve 19. Increase the resistance to move up. Conversely, when the water depth is shallow and the spherical float 30 moves downward, the tension of the spring 32 becomes weaker, reducing the resistance to upward movement of the spool 19b. In this way, the switching operating force of the hydraulic valve 19 is changed.

That is, the structure is such that the spherical float 30 as a water depth detector automatically adjusts the upward force of the central float 16, which is a depth detector of the tiller.

In addition, in the figure, 33 is a hydraulic tank, and 34 is a hydraulic pump. Reference numerals 35 and 35 denote side floats, which are provided at a predetermined interval on the left and right sides of the center float 16, and similarly to the center float 16, the rear part is pivoted with a pin, and the front part is attached with an expansion/contraction link 36. It is being

Next, to explain the operation of the above example, when seedlings are placed and accommodated in the seedling tank 14 and the tractor body 1 is propelled, and the rotating parts of the rice transplanter 12 are transmitted, the seedling planting rod 15 reciprocates from side to side. Seedlings are divided one by one from a seedling tank 14 and planted on the soil leveled by the center and side floats 16 and 35, which float and glide on the surface of the paddy field. Then, as the depth of the tiller changes, the front part of the central float 16 moves up and down due to changes in ground pressure, and the hydraulic switching valve 19 is switched to move the piston 10b of the hydraulic cylinder device 10 in and out. The rice transplanter 12 is made to move up and down.

However, at this time, if the water depth in the paddy field is deep, the spherical float 30, which is the water depth detector, moves upward and stretches the spring 32, increasing the upward movement resistance of the central float 16, which is the tiller depth detector. Close. For this reason, the sensitivity of pushing up the spool 19b of the hydraulic switching valve 19 and protruding the piston 10b to raise the rice transplanter 12 becomes dull, and even though the water in the rice field is deep, the rice transplanter 12 can be accurately grounded on the surface of the rice field and the seedlings can be planted at a deep depth. Prevent the water from becoming shallow.

Conversely, if the water depth is shallow, the spherical float 30
moves downward and the spring 32 contracts, so the center float 1
6's upward movement resistance becomes weaker. Therefore, the central float 14 is not pressed strongly against the surface of the paddy field, the running resistance is reduced, the distance between seedlings is not too small, and the seedlings can be planted accurately without being too deep. be exposed.

As described above, since the present invention has the above-described configuration, it is possible to prevent the plowing depth detector from erroneously detecting the depth of water in the paddy field. In particular, in the case of rice transplanters and seeding machines, when the water is deep, the tiller depth detector detects the depth deeper and the planting depth and sowing depth becomes shallower. It has the effect of preventing planting and deep sowing.

In the embodiment, the degree of extension of the spring 32 is directly adjusted using the spherical float 30, which is a water depth sensor. It is also possible to use a water depth sensor to change the electric resistance and adjust the degree of extension of the spring 32 using a motor or the like that outputs an output in proportion to the electric resistance.

[Brief explanation of drawings]

The figures show a riding type rice transplanter which is an embodiment of the present invention, in which Fig. 1 is a side view, Fig. 2 is a plan view, Fig. 3 is a side view of the main part, and Fig. 4 is the main part. FIG. 5 is a hydraulic circuit diagram. In the figure, the symbols 13 are the machine frame (planting mission case), 16 is the detection body (center float), 25 is the detection sensitivity adjustment device, and 30 is the water depth detection body (spherical float).

Claims (1)

[Claims] 1. A detector for detecting the depth of the tiller is provided on the frame of an agricultural machine for paddy fields, and the detector controls the lifting and lowering so that the machine frame is maintained at a substantially constant height from the surface of the paddy field. and a detection sensitivity adjustment device that automatically adjusts the detection sensitivity of the detection object to be insensitive when the water depth is deep and to be sensitive when the water depth is shallow, by a water depth detection object that detects the water depth of the rice field. Lifting control device for agricultural machinery used in paddy fields.