JPH05222745A - Automatic controller of construction machinery - Google Patents

Abstract

PURPOSE:To improve the controllability over a hydraulic actuator by inputting the detection signal of an operating state in an operating lever when this lever is made into manual operation, and making manual operation control take precedence over automatic control. CONSTITUTION:An automatic controller is provided with a detecting means which detects each of operation and nonoperation states in respective operating levers 16, 17, 18 and 19 operating various hydraulic actuators. In succession, when either of these operating levers 16, 17, 18, 19 is manually operated, pilot secondary pressure is derived from respective hydraulic remote-control valves 12, 13, 14, 15 of the operating lever operated, whereby the pilot secondary pressure acts on a pressure switch 45 by way of a shuttle valve 44 at the most downstream part. Next, a pressure detection signal out of the pressure switch 45 is inputted into a controller 33a. In succession, judgement takes place on the basis of this pressure detection signal at the controller 33a, and all solenoids of solenoid proportional pressure reducing valves 26 to 31 are made into an unenergized state. With this, automatic control is not carried out but manual operating control is performable instead.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic controller for construction machines such as hydraulic excavators and work vehicles.

[0002]

2. Description of the Related Art FIG. 4 is an overall side view of a hydraulic excavator. In the figure, 1 is an upper revolving structure which is a vehicle body, 2 is a lower traveling structure, 3 is a work attachment mounted on the front part of the upper revolving structure 1, 4 is a boom of the work attachment 3,
Reference numeral 5 is an arm, 6 is a bucket, 7 is a swing motor disposed on the upper swing body 1, 8L and 8R are left and right traveling motors disposed on the lower swing body 2, 9 is a boom cylinder, 10 is an arm cylinder, and 11 is a bucket cylinder. Is. FIG. 5 is a circuit diagram of essential parts showing a conventional automatic control device mounted on a hydraulic excavator. In the figure, reference numerals 10, 9, 11, and 7 denote arm cylinders, boom cylinders, bucket cylinders, swing motors, 12, 13, 1 as typical examples of various hydraulic actuators arranged in a hydraulic excavator.
4 and 15 are for arm, boom, bucket,
The turning hydraulic remote control valve (the hydraulic remote control valve can be operated in the crosswise direction of front, rear, left and right, but is shown divided for convenience of explanation), 16, 17, 18, 19 are hydraulic remote control valves 12, 13 , 14, 15 are operating levers, 20, 21, 22, 23 are directional switching valves for arm, boom, bucket, and swing pilot switching valves, 24 is a main pump, 25 is a pilot pump, 26, ˜, 31 are electromagnetic proportional pressure reducing valves which are electro-hydraulic converters, 33 is a controller, 34 is acting force detecting means for detecting an acting force such as a cylinder pressure sensor for rotating the bucket (6), and 35 is bucket attitude detecting means. Constituting boom angle sensor, 36 is a bucket angle sensor, 3
7 is an automatic / manual selection switch.

Next, a conventional automatic control device will be described with reference to FIGS. Some hydraulic excavators are equipped with an automatic control device capable of automatically performing general simple excavation called so-called digging or horizontal excavation that requires skilled operation skill. In the automatic control device shown in FIG. 5, bucket attitude detecting means for detecting the attitude of the bucket, acting force detecting means for detecting an acting force for rotating the bucket, and work around the rotation axis of the bucket based on the bucket attitude and acting force. Moment computing means for computing moments moment by moment, bucket rotation control means for controlling bucket rotation drive based on the computed work moment, and bucket lift control means for controlling bucket lift drive based on the work moment It has and. Therefore, when the automatic / manual selection switch 37 is automatically switched to perform the automatic excavation work, the excavation resistance R acting on the bucket 6 is detected as shown in FIG. 4, and the detection signal is input to the controller 33. The controller 33 performs arithmetic processing based on the detection signal, and outputs a command signal reflecting the result to the solenoids of the electromagnetic proportional pressure reducing valves (including the case of an electromagnetic opening / closing valve) 26, ..., 31. The electromagnetic proportional pressure reducing valve operates to apply the adjusted pilot secondary pressure to the pilot pressure receiving portion of the predetermined pilot switching valve via the shuttle valve (any one of 32, ..., 37). Let The pilot switching valve (20, 21, 22) is switched, and the hydraulic actuator (9,
~, 11) operates, so that automatic excavation control can be performed. When the automatic / manual selection switch 37 is switched to the manual mode, the solenoids of the electromagnetic proportional pressure reducing valves 26 to 31 are all de-energized, and the electromagnetic proportional pressure reducing valve is in the tank communicating position. Therefore, the hydraulic remote control valve (12,
It is possible to perform manual operation control with the operating levers (16, 18) of (14) to (14).

[0004]

Although the controller (CPU) equipped in the hydraulic excavator is a precision electronic device, a large shock or vibration acts during excavation work of the hydraulic excavator, and an area with a large temperature difference between high and low. But do the work. Therefore, when the controller causes an abnormality in the calculation result of the CPU during automatic control, the operation of the hydraulic excavator suddenly becomes runaway or does not move. When this unsafe condition suddenly occurred, there was no time to switch the automatic / manual selection switch to manual, so that the instantaneous manual operation could not be performed. In addition, when it is desired to intervene in a manual operation during automatic control, the automatic / manual selection switch must be switched to manual each time, which makes the operation troublesome. An object of the present invention is to provide an automatic control device that can solve the above problems.

[0005]

In the automatic control device of the present invention, detecting means for detecting the operating / non-operating states of the operating levers for operating various hydraulic actuators are provided, and any one of the operating levers for various hydraulic actuators is provided. When the operation lever is manually operated, the detection signal from the detection means is input to the controller, the controller makes a judgment based on the detection signal, and outputs a command signal to the electro-hydraulic converter to automatically perform the manual operation control. It was made to have priority by control.

[0006]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a circuit diagram of essential parts showing an automatic control device according to a first embodiment of the present invention. In the figure, the same reference numerals are given to those using the same constituent elements as those in the prior art. Three
Reference numerals 8, to 44 denote shuttle valves for selecting high pressure of pilot pressure, 45 is a pressure switch, and 33a is a controller. Next, the configuration of the first embodiment automatic control apparatus of the present invention will be described with reference to FIG. In the first embodiment automatic control device, operating levers (including the case of foot pedals) 17, 16, 1 for operating various hydraulic actuators 9, 10, 11, 7.
A shuttle valve 38 for selecting high pressure and a pressure switch 45 are provided as detection means for detecting the operated / non-operated state of 8 and 19, and any one of the operating levers 16 to 19 is manually operated. At this time, the detection signal from the pressure switch 45 is input to the controller 33a, and the controller 33a makes a determination based on the detection signal and outputs a command signal to the electromagnetic proportional pressure reducing valves 26, ..., 31 to perform the manual operation. Operation control is prioritized by automatic control.

Next, the operation of the automatic control system according to the first embodiment of the present invention will be described. First, automatic / manual selection switch 37
When is switched to manual, the automatic control operation is not performed, and the manual operation can be performed as in the prior art.
Next, the automatic / manual selection switch 37 is automatically switched to perform automatic control. The hydraulic actuators 9 to 11 are automatically operated and the hydraulic excavator performs a predetermined automatic excavation work. In this automatic control, all the operation levers 16 to 1 are operated.
9 is performed in the neutral position state. In this state, when the controller 33a suddenly breaks down and the operation of the hydraulic excavator changes, or one of the operating levers 16 to 19 is operated according to the driver's request. The pilot secondary pressure is derived from the hydraulic remote control valve of the operated operating lever, and the pilot secondary pressure acts on the pressure switch 45 via the shuttle valve 44 on the most downstream side. The pressure detection signal from the pressure switch 45 is sent to the controller 3
3a is input. The controller 33a makes a determination based on the pressure detection signal, and the electromagnetic proportional pressure reducing valves 26, ..., 31
De-energize all solenoids of. As a result, manual operation control can be performed without automatic control. Therefore, when the hydraulic excavator is performing automatic control, if an unsafe condition occurs in its operation, or if the driver feels unsatisfied with the form of mobile excavation, manual operation control is optional during the automatic control. Can be intervened.

Next, FIG. 2 is a main part circuit diagram showing an automatic control device according to a second embodiment of the present invention. In the figure, the same reference numerals are given to those that use the same components as those of the automatic control device according to the first embodiment. 46, 47, 48, 49 are pressure switches, and 33b is a controller. In this second embodiment automatic control device, in order to detect the operating / non-operating states of the operating levers 16, ..., 19 respectively, the pressure switch 4 for each hydraulic remote control valve 12 ,.
6 to 49 are arranged. Instead of this pressure switch, detection means such as a plurality of pressure sensors are provided. The function and function of the second embodiment controller in FIG. 2 are the same as those of the first embodiment automatic controller in FIG.

Next, FIG. 3 is a main part circuit diagram showing an automatic control device according to a third embodiment of the present invention. In the figure, the same reference numerals are given to those using the same constituent elements as those in the prior art.
50, 51, 52, 53 are electric joysticks for hydraulic actuators 10, 9, 11, 7 respectively, 54,
55, 56, 57 are electric joysticks 50, ..., 5
3, operation levers 58, 59, 60 and 61 are potentiometers for detecting the operation angles of the operation levers 54 to 57, and 33C is a controller. In the automatic controller of the third embodiment, the operating levers 54, ..., 5
7, the operation / non-operation state of the potentiometer 5 provided on the electric joysticks 50, ..., 53, respectively.
It can be detected by 8, ~, 61. The operation and function of the control device according to the third embodiment in FIG.
This is similar to the case of the automatic control device of the embodiment.

[0010]

When the controller mounted on the hydraulic excavator causes an abnormality in the calculation result of the CPU during automatic control, the operation of the hydraulic excavator suddenly becomes runaway,
It stops working. When this unsafe condition suddenly occurred, there was no time to switch the automatic / manual selection switch to manual, so that the instantaneous manual operation could not be performed. In addition, when it is desired to intervene in a manual operation during automatic control, the automatic / manual selection switch must be switched to manual each time, which is a troublesome operation. However, the automatic control device of the present invention is provided with detection means for detecting the operating / non-operating states of the operating levers for operating the various hydraulic actuators of the construction machine, and manually operating one of the operating levers for the various hydraulic actuators. When the operation is performed, the detection signal from the detection means is input to the controller, and the controller determines based on the detection signal and outputs a command signal to the electro-hydraulic converter so that the manual operation control has priority over the automatic control. I chose Therefore, when the automatic / manual selection switch is automatically switched and the hydraulic excavator is performing an automatic excavation work, for example, all the operation levers are kept in the neutral position. In this state, when the controller suddenly breaks down and the operation of the hydraulic excavator changes, or when the driver desires, one of the operation levers is operated. Then, the operation state detection signal of the operated operation lever is input from the detection means to the controller. The controller judges and outputs a command so that automatic control is not performed. That is, when an unsafe state occurs in the operation of the hydraulic excavator during automatic control, or when the driver feels unsatisfied with the form of automatic excavation, manual operation control should be performed during the automatic control. You can intervene at will. Therefore, in a construction machine, a work vehicle, etc. equipped with the automatic control device of the present invention, the operability of various hydraulic actuators during automatic control can be improved.

[Brief description of drawings]

FIG. 1 is a circuit diagram of essential parts showing an automatic control device according to a first embodiment of the present invention.

FIG. 2 is a circuit diagram of a main part showing an automatic control device according to a second embodiment of the present invention.

FIG. 3 is a circuit diagram of essential parts showing an automatic control device according to a third embodiment of the present invention.

FIG. 4 is an overall side view of the hydraulic excavator.

FIG. 5 is a circuit diagram of essential parts showing a conventional automatic control device.

[Explanation of symbols]

 3 Work Attachment 7 Swing Motor 9 Boom Cylinder 10 Arm Cylinder 11 Bucket Cylinder 12, ~, 15 Hydraulic Remote Control Valve 16, ~, 19, 54, ~, 57 Operating Lever 20, ~, 23 Pilot Switch Valve 25 Pilot Pump 26, ~ , 31 Electromagnetic proportional pressure reducing valve 33, 33a, 33b, 33c Controller 37 Automatic / manual selection switch 38, ~, 44, 62, ~, 67 Shuttle valve 45, 46, ~, 49 Pressure switch 50, ~, 53 Electric joystick 58 , ~, 61 Potentiometer

Claims (1)

[Claims] 1. A work attachment is attached to a front portion of a vehicle body, various hydraulic actuators are arranged on the vehicle body and the work attachment, and the various hydraulic actuators can be controlled by a manual operation of an operating lever,
Further, any one of various hydraulic actuators can be automatically controlled without operating the operation lever, and the direction switching valve of the hydraulic actuator that can be automatically controlled is operated via the controller and the electro-hydraulic converter. When a control device for a construction machine is provided with detection means for detecting the operating / non-operating states of the operating levers for operating various hydraulic actuators, and when any one of the operating levers for various hydraulic actuators is manually operated. By inputting the detection signal from the detection means to the controller, the controller judges based on the detection signal, and outputs a command signal to the electro-hydraulic converter so that the manual operation control has priority over the automatic control. An automatic control device for construction machinery.