JPH075023Y2 - Steering control device for mobile agricultural machinery - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial application field" The present invention is equipped with front and rear wheel steering steering sensors for detecting guide wires laid on a road surface, and the front and rear wheels are independently steered based on the detection of the sensors. The present invention relates to a steering control device for a mobile agricultural machine such as a speed sprayer that steers the machine body along the wire.

"Prior Art" In this type of means for steering the body by independently steering the front and rear wheels, the respective steerings are performed substantially at the same time without any time difference.

"Problems to be solved by the device" However, in the case of the above-mentioned conventional means, not only is the vehicle body shaken unnecessarily, and in the case of a speed sprayer, the chemical liquid is not accurately sprayed, and not only is there a danger of chemical damage, However, there are drawbacks such as hunting during automatic steering control.

[Means for Solving Problems] Accordingly, the present invention is provided with front and rear wheel steering steering sensors that detect guide wires laid on a road surface, and independently steers the front and rear wheels based on the detection by the sensors. In a structure in which the steering wheel is steered along the wire, a control comparison device for determining the magnitude of the steering control amount between the front and rear wheels is provided.
The configuration is such that the control is performed from the one having the larger steering control amount of the front and rear wheels.

[Operation] According to the present invention, the steering wheel having the larger control amount of the front and rear wheels is first steered, and then the steering wheel having the smaller control amount is steered to prevent the front and rear wheels from being displaced with respect to the guide wire. Can be corrected smoothly and stably without conflicts, and automatic steering control can be performed with high accuracy without hunting. In particular, speed sprayers can accurately spray chemicals to prevent uneven spraying. The occurrence can be prevented.

[Embodiment] An embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a control circuit diagram, FIG. 2 is an overall side view of the speed sprayer, and FIG. 3 is a plan view of the same. In the figure, (1) is a speed sprayer that is a mobile agricultural machine, (2) is a driver's seat, ( 3)
Is a chemical liquid tank, (4) is a spray nozzle, (5) is a blower fan for spraying, (6) and (6) are front left and right wheels, (7) and (7) are left and right rear wheels, (8) is an engine, and (9) is Is the mission, (1
0) and (11) are front and rear propulsion shafts, and (12) and (13) are front and rear axle cases. The front and rear wheels (6) and (7) are driven by the output of the engine (8) so that the aircraft can run. I am configuring.

Further, front and rear steering valves (18) and (19) and front and rear wheels (6) and (7) which are switched by front and rear steering solenoids (14) and (15) or a steering handle (17) having a front and rear steering connection and switching device (16). A front and rear steering cylinder (20) (21) for steering control, that is, steering, is provided, and the cylinder (20) (21) is connected to a hydraulic pump (22) interlocking with the engine (8) via steering valves (18) (19). ) Is hydraulically connected to the handle (1
7) Manual operation or solenoid (14) (15)
The steering control is performed by the excitation operation of.

As shown in FIG. 4, front and rear magnetic sensors (23a) (23b), (24a) (2) which are a pair of left and right steering sensors on the left and right sides below the front end and the rear end of the speed sprayer (1).
4b) is provided to detect the guide wire (25) laid in the orchard, and each sensor (23a) (23b) (24a) is attached to the mounting bases (26) on the lower left and right sides of the front and rear machine base (1a). (24b) is attached to the guide wire (25) laid on the road surface so that the detection surface faces the left and right sides at the same distance.
When a direct current or an alternating current is applied from the power source (27) connected to 5) and a magnetic field is generated in the wire (25), the strength of the magnetic field is measured by each sensor (23a) (23b) (24a). (twenty four
b) It is configured to detect with.

By the way, front and rear steering angle sensors (28, 29) for detecting the steering angles of the front and rear wheels (6, 7) are installed in the cylinders (20) (2).
1), a traveling speed sensor (30) for detecting the traveling speed position, and an electric cylinder (31) for traveling shift control for shifting the mission (9) are provided, and as shown in FIG. The steering control circuit (32), which is a control and comparison device composed of a computer, has an automatic / manual switch (33) for switching between automatic steering and manual steering, and left and right front wheels (6) (6) when manually Steering control of front and rear two wheels only for rear wheels (7) and (7) and front and rear wheels (6) (6) (7)
(7) A steering selection switch (34) for selecting the steering system of front-rear in-phase or opposite-phase steering control on four wheels, and front and rear magnetic sensors (23a) (23b) (24a) (24b) Front and rear steering angle sensors (28) and (29), the traveling speed change position sensor (30), and a traveling position setter (35) for setting a steering reference line of the airframe with respect to the wire (25), that is, a traveling position. Input and connection of the front and rear steering valves (18) (19)
, Automatic / manual indicator lamp (36) and each magnetic sensor (23
a) (23b) (24a) (24b) input detection monitor for magnetic detection (37), chemical tank (3) empty state and each sensor (23a) (23b) (24a) (24b) An output of a steering control circuit (32) is connected to an alarm buzzer (38) that sounds when a setting input cannot be obtained, and the traveling shift control electric cylinder (31), and the magnetic sensor (23a) ( twenty three
b) Based on the magnetic field strength from the wire (25) detected by (24a) and (24b), the airframe is configured to follow and steer along the wire (25).

This embodiment is configured as described above, and its operation will be described below with reference to the flowchart of FIG.

Right and left magnetic sensors (23a) (23b), (24a) (2
4b) each value (F _L ) (F _R ) ・ (R _L ) (R _R ) is the control circuit (3
When read by 2), front and rear sensors (23a) (23b)
Left / Right output difference of (24a) and (24b) (F _X ) (R _X ) (F _X = | F _L −
F _R |, R _X = | R _L −R _R |) is calculated, and this output difference (F _X )
When one or both of (R _X ) are in the dead zone or above, the steering valves (18) and (19) are appropriately operated to perform automatic steering control. That is, when both the front and rear output differences (F _X ) (R _X ) are above the dead zone, it is determined which of the front and rear output differences (F _X ) (R _X ) is larger. _When ( _X ) is smaller than the rear output difference (R _X ), (F _X <R _X ), steering is performed from the rear wheel (7) side, which has a large control amount, and a fixed dead time (T ₁ ) is reached after the steering is completed. Front wheel (6) with a small amount of control after passage
Side steering is performed. When the front output difference (F _X ) is larger than the rear output difference (R _X ) (F _X > R _X ), steering is performed from the front wheel (6) side, which has a large control amount, and After a certain dead time (T ₂ ), the rear wheel (7) with a small control amount is steered to maintain the output difference (F _X ) (R _X ) on the left and right at approximately zero (25). Steering that accurately follows.

On the other hand, when either (F _X ) or (R _X ) of the output difference (F _X ) (R _X ) of the front and rear parts is in the dead zone or above, only steering of the front and rear wheels (6) or (7) on this side is performed. The steering control of the airframe is performed to the left or right side by the control amount according to the left-right output difference (F _X ) (R _X ).

Fig. 6 shows the front left and right magnetic sensors (23a) (23b) when moving forward.
Shows an example configuration in which both the front and rear wheels (6) and (7) are steered, and the rear left and right magnetic sensors (24a) and (24b) steer both front and rear wheels (6) and (7) when moving backward. The steering amount on the rear side is reduced with respect to the steering amount on the front side in the direction.

That is, the steering control is performed within the maximum allowable control range by matching the steering amounts with the front wheels (6) and the rear wheels (7) during manual steering, while the wire (25) is controlled during automatic steering. The sensors (23a) (23b) (24a) (24b) detect forward or reverse or neutral traveling command signals having different frequencies applied, and the forward or backward or neutral gear shifting of the machine body is performed. Further, at this time, when the vehicle is moving forward, the steering allowable control amount of the rear wheels (7) is reduced to about 1/2 of that of the front wheels (6). The value of the front left and right magnetic sensors (23a) (23b) (F _L ) (F _R ) that is read while moving forward after reducing the steering allowable control amount of the front wheel (6) at the position to about 1/2 Output difference (| F _L −F
_{When R} | is above the dead zone, the output difference (| F _L −F _R
| Simultaneously setting amount in accordance with) (x) minute wheel (6) is steered to the left and right, half the amount of the set amount of the front wheel (6) (x) ^(x
/ 2) The rear wheels (7) are steered to the left or right in the opposite phase to the front wheels (6).

The output difference also rear left and right magnetic sensor are read even in reverse as well (24a) the value of _{(24b) (R L) (} R R) (| R L
-R _R |) is above the dead zone, the output difference (| R _L −
The rear wheel (7) is steered to the left or right by a set amount (x) according to R _R |), and at the same time, the front wheel (7) is moved by half the set amount (x) ( ^x / 2). The steering wheel is steered to the left or right in a phase opposite to that of the rear wheel (7).

In this way, the steering amounts of the front and rear wheels (6) and (7) are made equal during the manual steering, and at the time of automatic steering, the rear wheels (7) or () with respect to the front wheels (6) or (7) in the traveling direction. Since the amount of steering in 6) is reduced, it is possible to prevent swinging of the rear part of the vehicle body during turning during automatic steering, avoid collision with obstacles such as fruit trees, and drive during manual steering. It is possible to ensure the ease of.

In this case, a control circuit for steering the front wheels (6) and a control circuit for steering the rear wheels (7) may be separately provided to perform control.

[Advantages of the Invention] As is apparent from the above embodiments, the present invention detects the front and rear wheels (6) for detecting the guide wire (25) laid on the road surface.
(7) Steering steering sensor (23a) (23b) (24a) (24
b), the sensor (23a) (23b) · (24a) (24b)
In the structure in which the front and rear wheels (6) and (7) are independently steered based on the detection of the vehicle to steer the aircraft along the wire (25), the steering control amount between the front and rear wheels (6) and (7) Since the control comparing device (32) for discriminating the size of the vehicle is provided and the control is performed from the one of the front and rear wheels (6) and (7) having the larger steering control amount, the displacement of the machine body with respect to the guide wire (25) is Since the steering of the front and rear wheels (6) and (7) can be corrected smoothly and stably without competition, the automatic steering control can be performed with high accuracy without causing hunting, and especially in a speed sprayer. It has a remarkable effect that the drug is accurately sprayed to prevent uneven spraying.

[Brief description of drawings]

FIG. 1 is a steering control circuit diagram, FIG. 2 is an overall side view of a speed sprayer, FIG. 3 is an explanatory view of the same plane, FIG. 4 is an explanatory diagram of left and right magnetic sensor portions, FIG. 5 is a flowchart, and FIG. The figure is a flow chart in another embodiment. (6) ... front wheel (7) ... rear wheel (23a) (23b) (24a) (24b) ... magnetic sensor (steering sensor) (25) ... induction wire (32) ... control circuit (control comparison device)

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location // B62D 113: 00 137: 00

Claims (1)

[Scope of utility model registration request] 1. A front and rear wheel steering steering sensor for detecting a guide wire laid on a traveling road surface, wherein the front and rear wheels are independently steered based on the detection of the sensor to steer the machine body along the wire. In the structure described above, a control / comparison device that determines the magnitude of the steering control amount between the front and rear wheels is provided, and the control is performed from the one with the larger steering control amount of the front and rear wheels. Control device.