JPH0363328B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a method for controlling ground work equipment such as a seedling planting device or a seeding device based on changes in ground pressure of a ground body equipped on the ground work device, such as a seedling planting device or a seeding device. The present invention relates to a ground pressure detection device for a paddy field working machine, which is used to control the drive up and down of a traveling machine.

[Conventional technology]

This type of ground pressure detection device is equipped with a spring that swings and biases a ground body that can freely swing up and down relative to the ground work device in the direction of contact with the ground, and also includes a spring that swings and urges a ground body that can freely swing up and down relative to the ground work device. There are some that are equipped with a sensor that detects dynamic displacement.

[Problem that the invention seeks to solve]

In the case of this conventional device, the detection standard ground pressure of the grounding body is set by adjusting the biasing force of a spring based on the operator's intuition. There is a problem in that large variations tend to occur between the ground pressure and the actual ground pressure, resulting in a decrease in attitude control accuracy of the ground work equipment.

The purpose of the present invention is to improve the above-mentioned conventional problems by modifying the ground pressure detection system, and at the same time to improve the degree of freedom in design when installing sensors as much as possible. has.

[Means for solving problems]

The characteristic configuration of the ground pressure detection device for a paddy field working machine according to the present invention is that a flexible pressure-receiving membrane-like body that receives pressure from the soil is provided on the lower surface of the ground body of the ground-working machine, and the inner surface of this pressure-receiving membrane-like body An incompressible medium is sealed in a pressure sensing chamber formed using the pressure sensing chamber, and a pressure sensor is provided that outputs an electrical signal in accordance with the pressure propagated from the pressure-receiving membrane-like body via the enclosing medium. Its functions and effects are as follows.

[Effect]

In other words, since the pressure acting on the pressure-receiving membrane-like body on the lower surface of the ground body is detected as an electrical quantity by a pressure sensor such as a piezoelectric element or a semiconductor strain gauge, even minute ground pressure changes can be detected with high precision.
Moreover, since an incompressible medium such as water or oil is interposed in the pressure transmission system from the pressure-receiving membrane-like body to the pressure sensor, a pressure sensing chamber for enclosing this incompressible medium is formed, for example. By appropriately selecting the length of the flexible hose with no or very little change in diameter, the pressure sensor can be installed at any position.

〔Effect of the invention〕

Therefore, since the ground pressure of the grounding body can be electrically detected with high precision using a pressure sensor, the detection reference ground pressure can also be set electrically easily and accurately, making ground work easier as a whole. It is possible to improve the attitude control accuracy of the device. Moreover, since the pressure sensor can be installed at any location depending on conditions such as space and disturbance factors, design freedom can be improved at the same time.

〔Example〕

A first embodiment of the present invention will be described below with reference to FIGS. 1 to 4.

A is engine E, driving section 1, front and rear wheels 2, 3
B is an example of a ground working device, and B is a seedling planting device connected to the machine A via a parallel quadruple link mechanism 4 so that it can be raised and lowered; , B constitute a riding type rice transplanter which is an example of a paddy field working machine.

The seedling planting device B includes a seedling platform 5 that is reciprocally movable in the left and right direction, a link mechanism 7 that circulates the planting claw 6 between the seedling outlet of the seedling platform 5 and the mud surface, and , a planting case 8 that houses a transmission mechanism therefor, and three ground floats 9.

Reference numeral 10 denotes a hydraulic cylinder for driving up and down the seedling planting device B, which is installed between the machine A and the parallel quadruple link mechanism 4, and an electromagnetic up and down control is provided in the hydraulic circuit for this hydraulic cylinder 10. A valve 11 is interposed.

S is a grounding pressure detection device attached to the central grounding float (an example of a grounding body) 9 of the seedling planting device B, which forms a pressure sensing chamber 12 opening downward in the grounding float 9. A flexible pressure-receiving film-like body B made of hard and highly abrasion-resistant rubber, which closes the opening of the pressure sensing chamber 12, is flush with or almost flush with the lower surface of the grounding float 9. At the same time, an incompressible fluid (an example of a medium) such as water or oil is sealed in the pressure sensing chamber 12, and a ceiling portion 9a of the ground float 9 corresponding to the pressure sensing chamber 12 is sealed. is a semiconductor strain gauge (an example of a pressure sensor) 15 that acts on the pressure-receiving membrane-like body 13 and converts the pressure propagated through the enclosed fluid into an electric signal and continuously detects it. is attached.

Based on the detection signal from the strain gauge 15 of the ground pressure detection device S, C is a seedling planting device B so that the detected ground pressure value becomes the set ground pressure value.
This is a mechanism that controls the drive up and down of this machine A.
This elevation control mechanism C is constructed as follows.

That is, from the strain gauge 15 to the amplifier circuit 1
6 and the setting signal from the ground pressure setting device 17 are input to the comparison circuit 18 to compare whether the detected ground pressure value is within the allowable range of the set ground pressure value. Thereafter, the comparison signal from the comparison circuit 18 is input to the arithmetic circuit 19. This arithmetic circuit 19 maintains the lift control valve 11 in a neutral state when the detected ground pressure value is within the allowable range, and maintains the lift control valve 11 in the lift neutral state when the detected ground pressure value increases beyond the allowable range. The solenoid 11a is energized to switch the valve 11 from the vertical neutral state to the raised state, and when the detected ground pressure value decreases below the allowable range, the lowering solenoid 11b of the vertical control valve 11 is energized to switch the valve 11 from the vertical neutral state to the raised state. The control signal is configured to output a control signal to the drive circuits 20a, 20b for the solenoids 11a, 11b in order to switch the solenoid from the neutral state to the descending state.

[Another example]

(a) As shown in FIG. 5, the pressure sensing chamber 12
It consists of a hole 12a formed in the ground float 9 and a flexible hose 12b with no or very little diameter change connected to the hole 12a, and a strainer attached to the other end of the hose 12b. A gauge 15 is disposed near the operating section 1 of the machine A.

According to this embodiment, the strain gauge 1
It has the advantage that important parts of the sensor system and control system such as 5 can be protected from mud, water, etc., and can also be easily protected from external shocks.

(b) As shown in FIG. 6, the pressure sensing chamber 12 formed in the grounding float 9 is configured in the shape of a tapered tape that expands downward.

(c) As the ground work device B, although a seedling planting device was used in the above embodiment, the present invention is not limited to this, and for example, a seeding device or the like may be used.

(d) As the pressure sensor 15, a strain gauge such as a metal strain gauge or a semiconductor strain gauge was used in the above embodiment, but an actuating transformer, a piezoelectric element, etc. may be used instead.

[Brief explanation of drawings]

1 to 4 show a first embodiment of a ground pressure detection device for a paddy field working machine according to the present invention, and FIG.
FIG. 2 is a partially cutaway side view and plan view of the grounding float, FIG. 3 is a block diagram of the control system, and FIG. 4 is an overall side view of the riding rice transplanter. FIG. 5 is a rear side view of the riding rice transplanter according to the second embodiment, and FIG. 6 is a longitudinal sectional side view of the main parts of the grounding float according to the third embodiment. B...Ground work device, 9...Grounding body, 12...
Pressure sensing chamber, 13...pressure-receiving membranous body, 15...pressure sensor.

Claims (1)

[Scope of Claims] 1. A flexible pressure-receiving membrane-like body B that receives pressure from the soil is provided on the lower surface of the ground installation body 9 of the ground work device B,
An incompressible medium is sealed in the pressure sensing chamber 12 formed using the inner surface of the pressure-receiving membrane-like body B, and the pressure transmitted from the pressure-receiving membrane-like body B through the enclosing medium is responded to. This is a ground pressure detection device for a paddy field working machine, which is equipped with a pressure sensor 15 that outputs an electric signal. 2. The ground pressure detection device for a paddy field working machine according to claim 1, wherein the pressure sensor 15 is attached to the ground body 9. 3. The ground pressure detection device for a paddy field working machine according to claim 1, wherein the pressure sensor 15 is attached to the traveling machine body side.