JPH0740814B2 - Rice transplanter - Google Patents

Description

TECHNICAL FIELD The present invention relates to a rice transplanter characterized by an automatic speed change gear structure.

[Conventional technology]

In automatic shifting of rice transplanter, for example, Japanese Patent Publication No. 60-56453
As disclosed in the publication, in a soft mud state in which mud pushing phenomenon that adversely affects planted seedlings often occurs, it runs at a low speed to suppress the occurrence of mud pushing phenomenon and a hard mud state in which mud pushing phenomenon does not occur Some of them are configured to run at high speed to improve planting efficiency.

[Problems to be Solved by the Invention]

As the structure to detect the hardness of the mud in the disclosed structure, a rod-shaped sensor is thrust into the mud and placed in the mud. If the mud is hard, the reaction force from the mud The rod-shaped sensor swings upward, and if the mud is soft, the rod-shaped sensor swings downward due to the downward biasing force, and the mud hardness is detected by the swing amount of the rod-shaped sensor. I have to.

However, since a large amount of straw dust or the like is scattered in the mud, if the straw dust or the like is entangled with the rod-shaped sensor, the rod-shaped sensor cannot accurately detect the mud hardness. Further, such a grounding type will be greatly affected by the traveling speed of the aircraft.

Here, the present invention has been made in view of the above-mentioned problems, and an object thereof is to perform automatic gear shifting based on mud hardness without being affected by the dust and the traveling speed of the airframe. I am trying.

[Means for Solving the Problems]

A characteristic configuration of the present invention includes a torque sensor that detects a torque generated in a driving wheel for traveling and a depth sensor that detects a depth from a field scene to a tiller, and a detection depth by the depth sensor. However, when it becomes shallower than the depth preset as the reference level in the detected torque, or the torque detected by the torque sensor becomes larger than the value preset as the reference torque in the detected depth. In this case, a control means for operating the traveling transmission to the high speed side is provided.

[Work]

The drive wheels for traveling in the rice transplanter drive on the cultivator below the field scene, and the mud acts as a resistance against the drive wheels. Since this resistance is mainly determined by the hardness of the mud and the depth to the tiller, even though the torque generated by the torque sensor for the driving wheels for traveling is constant, the depth sensor When the depth from the field scene to the tiller detected by means becomes shallower than the reference level at the preset detection torque, or the depth from the field scene to the tiller detected by the depth sensor is constant. Nevertheless, when the torque generated by the drive wheel for traveling detected by the torque sensor becomes larger than the reference torque at the preset detection depth, the mud in the field becomes hard and a large resistance is exerted on the drive wheel. Since it can be determined that it is working, the traveling speed should be increased based on these.

〔The invention's effect〕

As described above, the ground-type rod-shaped sensor, which is easily affected by straw scraps and traveling speed, is abolished, and the relationship between the depth to the tiller and the torque generated on the drive wheels and the mud hardness is effectively used. , The mud hardness can be indirectly detected almost accurately without being affected by the dust and the traveling speed and the traveling speed, and the automatic shift can be accurately performed.

〔Example〕

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

As shown in FIG. 1, an engine (3) is provided at the front of the airframe supported by front wheels (1) and rear wheels as driving wheels (2),
A seedling planting device including a planting arm (4) and a seedling stand (5) is attached to the rear part of the machine body so as to be vertically movable through a four-link mechanism (6). Is configured.

The drive shaft (not shown) of the rear wheel (2) is provided with a torque sensor (7) acting on the rear wheel (2). The torque sensor (7) is attached to the drive shaft. Magnetostrictive body (not shown) made of amorphous material, field coil (not shown) that creates a magnetic field for this magnetostrictive body, and magnetostriction of the magnetostrictive body caused by twisting of the drive shaft are detected. It is composed of a detection coil (not shown) and the like, and the torque generated in the rear wheel (2) is detected as the twist of the drive shaft.

And in the lower center of the machine, from the field scene (G) to the tiller (H).
An ultrasonic sensor as a depth sensor (8) for determining the depth (D) is attached. The height from the field scene (G) to the ultrasonic sensor (8) is detected by this ultrasonic sensor (8), but the lower surface of the front and rear wheels (1), (2) (on the tiller (H)). Since the height from the grounded part) to the ultrasonic sensor (8) is determined, the height from the field scene (G) to the ultrasonic sensor (8) is obtained by the ultrasonic sensor (8), The depth (D) is obtained by subtracting this from the height.

Then, the power of the engine (3) is transferred from the belt-type continuously variable transmission (9) of the split pulley type to the transmission (1
It is transmitted to the front and rear wheels (1) and (2), and based on the signals from the torque sensor (7) and the ultrasonic sensor (8), the control device (11) is of belt type. The transmission section (9a) of the continuously variable transmission (9) is operated as follows.

That is, as shown in FIG. 2, when the depth (D) from the field scene (G) to the tiller (H) obtained by the ultrasonic sensor (8) is a constant value, the torque sensor ( It is determined that the mud becomes harder as the value of the torque acting on the rear wheel (2) detected by 7) increases, and the belt type continuously variable transmission (9) is operated to the high speed side ( See the relationship line (A ₁ )). When the depth (D) becomes deep when the mud hardness is constant, the relationship line shifts to the low speed side (see the relationship line (A ₂ )), and when the depth (D) becomes shallow, the relationship line becomes high. it is going to shift to the side (see relationship line (a _3)). That is, when the torque acting on the rear wheel (2) detected by the torque sensor (7) has a constant value, the shallower the depth (D) is, the harder the mud is, and the belt type continuously variable transmission is determined. The device (9) is operated to the high speed side.

[Another embodiment]

In the above-described embodiment, the belt type continuously variable transmission (9) is used to perform the gear shift operation, but the gear shift operation may be performed by changing the accelerator opening of the engine (3).

Moreover, regarding the detection of the depth (D), the raising / lowering control device for automatically raising / lowering the seedling planting device by the four-link mechanism (6) so as to maintain a constant height from the field scene (G) is mounted. Since the model rice transplanter is equipped with it, a potentiometer for detecting the swing angle of the quadruple link mechanism (6) is attached to the connection portion of the quadruple link mechanism (6) on the machine side, and the quadruple link mechanism (6) The height from the field scene (G) to the potentiometer is calculated based on the swing angle of, and this height is subtracted from the height from the lower surface of the front and rear wheels (1) and (2) to the potentiometer to obtain the depth (D). May be asked.

It should be noted that reference numerals are added to the claims for convenience of comparison with 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 rice transplanter according to the present invention. Fig. 1 is an overall side view of a riding type rice transplanter, and Fig. 2 is an operation on a rear wheel when the depth from the field scene to the tiller is constant. It is a figure which shows the relationship between the torque which carries out, and the traveling speed of an airframe. (2) …… Drive wheels, (7) …… Torque sensor,
(8) ... depth sensor, (9) ... traveling transmission, (11) ... control device, (G) ... field scene, (H) ...
… Plow, (D) …… Depth from the field scene to the plow.

Claims (1)

[Claims] 1. A torque sensor (7) for detecting a torque generated in a driving wheel (2) for traveling, and a depth sensor (D) for detecting a depth (D) from a field scene (G) to a tiller (H). (8) and when the depth detected by the depth sensor (8) becomes shallower than the depth preset as a reference level in the detected torque, or by the torque sensor (7). A control means (11) for operating the traveling transmission (9) to a high speed side when the torque becomes larger than a value preset as a reference torque at the detected depth is provided. Rice transplanter.