AUTOMATIC CONTROL SYSTEM AND METHOD FOR JOYSTICK CONTROL-BASED CONSTRUCTION EQUIPMENT

• US 20150308078A1
• Filed: 11/20/2013
• Published: 10/29/2015
• Est. Priority Date: 12/13/2012
• Status: Active Grant

• Current Assignee: HD Hyundai Construction Equipment Co., Ltd.
• Original Assignee: Hyundai Heavy Industries Company Limited (Korea Shipbuilding & Offshore Engineering Co., Ltd.)
• Inventors: LEE, Jong Chan, CHOI, Lim Gook, KWON, Young Min, YIM, Jong Hyung
• Granted Patent: US 9,739,036 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: E02F 3/42 Drives for dippers, buckets, dipper-arms or bucket-arms
• CPC Class Codes: E02F 3/434 providing automatic sequences of movements, e.g. automatic dumping or loading, automatic return-to-dig
• CPC Class Codes: E02F 3/437 providing automatic sequences of movements, e.g. linear excavation, keeping dipper angle constant
• CPC Class Codes: E02F 9/2004 Control mechanisms, e.g. control levers control levers per se G05G
• CPC Class Codes: E02F 9/2025 Particular purposes of control systems not otherwise provided for E02F3/16, E02F3/26, sub-groups of E02F3/43, E02F3/651, sub-groups of E02F3/84, E02F3/907, E02F5/145 take precedence
• CPC Class Codes: E02F 9/2203 Arrangements for controlling the attitude of actuators, e.g. speed, floating function
• CPC Class Codes: E02F 9/2228 including an electronic controller
• CPC Class Codes: E02F 9/2267 Valves or distributors position of valves arrangements on upper-structures E02F9/0875
• CPC Class Codes: E02F 9/2289 Closed circuit
• CPC Class Codes: E02F 9/2296 Systems with a variable displacement pump
• CPC Class Codes: E02F 9/265 with follow-up actions (e.g. control signals sent to actuate the work tool)
• CPC Class Codes: F15B 11/006 Hydraulic "Wheatstone bridge" circuits, i.e. with four nodes, P-A-T-B, and on-off or proportional valves in each link
• CPC Class Codes: F15B 11/161 with sensing of servomotor demand or load
• CPC Class Codes: F15B 13/085 Electrical controllers
• CPC Class Codes: F15B 13/086 Sensing means, e.g. pressure sensors
• CPC Class Codes: F15B 21/02 Servomotor systems with programme control derived from a store or timing device; Control devices therefor
• CPC Class Codes: F15B 2211/20546 variable capacity
• CPC Class Codes: F15B 2211/30575 in a Wheatstone Bridge arrangement (also half bridges)
• CPC Class Codes: F15B 2211/327 electrically or electronically
• CPC Class Codes: F15B 2211/6346 representing a state of input means, e.g. joystick position
• CPC Class Codes: F15B 2211/75 : Control of speed of the output member

Abstract

According to the present invention, a hydraulic system of construction equipment is implemented as a close center system, which converts an input signal of an electric or hydraulic joystick into a speed signal of a work apparatus, and controls a speed of the work apparatus regardless of an external load condition, thereby minimizing fatigue of a worker to improve work efficiency, improving a work apparatus operation ability of an unskilled person, and patterning standardized work to implement automation of construction equipment.

Claims

1. A system for automatically controlling construction equipment, to which a joystick is applied, based on a joystick control, comprising:

a hydraulic pump (30, 300) configured to discharge working fluid within a hydraulic tank (20, 200) and supply the working fluid to an actuator (40, 400);

the actuator (40, 400) configured to drive the construction work apparatus with the working fluid of the hydraulic pump (30, 300);

first electronic hydraulic control valves (50 and 50′

, 500 and 500′

) installed in a piston-side inlet flow path (41, 410) and a rod-side inlet flow path (42, 420) connected from the hydraulic pump (30, 300) to the actuator (40, 400);

second electronic hydraulic control valves (60 and 60′

, 600 and 600′

) installed in a piston-side outlet flow path (21, 210) and a rod-side outlet flow path (22, 220) connected from the actuator (40, 400) to the hydraulic tank (20, 200); and

a control unit (70, 700) configured to independently control the first electronic hydraulic control valves (50 and 50′

, 500 and 500′

) and the second electronic hydraulic control valves (60 and 60′

, 600 and 600′

) connected to the actuator (40, 400).

2. The system of claim 1, wherein the joystick is an electric joystick (10), and when an electric signal is generated by an operation of the electric joystick (10), the control unit (70) controls the first electronic hydraulic control valves (50 and 50′

) and the second electronic hydraulic control valves (60 and 60′

) connected to the actuator (40, 400) by using the electric signal generated by the operation of the electric joystick (10).

3. The system of claim 1, wherein the joystick is a hydraulic joystick (100), and

the system further comprises a pressure sensor (800) converting a pilot pressure formed by an operation of the hydraulic joystick (100) into an electric signal, and

the control unit (700) controls the first electronic hydraulic control valves (500, 500′

) and the second electronic hydraulic control valves (600, 600′

) connected to the actuator (400) by using an electric signal generated by the pressure sensor (800).

4. The system of claim 2, wherein the control unit (70, 700) further includes a controller (71, 710) converting a coded electric signal, which is in proportion to a stroke, by an operation of the electric joystick (10) or the hydraulic joystick (100) into a speed signal, so that an open/close of the first electronic hydraulic control valves (50 and 50′

, 500 and 500′

) and the second electronic hydraulic control valves (60 and 60′

, 600 and 600′

) is controlled, and a work speed of the construction work apparatus is changed.

5. The system of claim 4, wherein an area of the flow path is variably controlled by the first electronic hydraulic control valves (50 and 50′

, 500 and 500′

) and the second electronic hydraulic control valves (60 and 60′

, 600 and 600′

) according to an operation quantity of the electric joystick (10) or the hydraulic joystick (100).

6. The system of claim 2, wherein the control unit (70, 700) further includes a storage unit (72, 720) storing an electric signal and a speed signal generated according to an operation of the electric joystick (10) or the hydraulic joystick (100) in real time, and a monitoring unit (73, 730) monitoring an electric signal and a speed signal generated according to an operation of the electric joystick (10) or the hydraulic joystick (100) in real time.

12. The system of claim 3, wherein the control unit (70, 700) further includes a controller (71, 710) converting a coded electric signal, which is in proportion to a stroke, by an operation of the electric joystick (10) or the hydraulic joystick (100) into a speed signal, so that an open/close of the first electronic hydraulic control valves (50 and 50′

, 500 and 500′

) and the second electronic hydraulic control valves (60 and 60′

, 600 and 600′

) is controlled, and a work speed of the construction work apparatus is changed.

13. The system of claim 3, wherein the control unit (70, 700) further includes a storage unit (72, 720) storing an electric signal and a speed signal generated according to an operation of the electric joystick (10) or the hydraulic joystick (100) in real time, and a monitoring unit (73, 730) monitoring an electric signal and a speed signal generated according to an operation of the electric joystick (10) or the hydraulic joystick (100) in real time.

7. A method of automatically controlling construction equipment based on a joystick control, comprising:

a) converting a signal generated by an operation of a joystick lever of a construction work apparatus into an electric signal, and inputting the electric signal (S10, S100);

b) converting the electric signal of the joystick lever into a speed signal of the construction work apparatus (S20, S200);

c) selecting an automatic excavation function of the construction work apparatus (S30, S300);

d) storing an operation signal of the joystick lever (S40, S400);

e) performing automatic excavation (teach &

play back) by the construction work apparatus (S50, S500);

f) generating control signals of a pump and an electronic hydraulic valve according to the pre-stored operation signal of the joystick lever (S60, S600); and

g) driving actuators of the construction work apparatus (S70, S700).

8. The method of claim 7, wherein the joystick is any one of an electric joystick (10) and a hydraulic joystick (100).

9. The method of claim 8, further comprising:

generating control signals of a pump and an electronic hydraulic valve according to a lever signal of the electric joystick (10) or the hydraulic joystick (100) when the automatic excavation function of the construction work apparatus is not selected in operation c) (S300).

10. The method of claim 8, wherein a button or a kind of switch is further provided at the electric joystick (10) or the hydraulic joystick (100), or a separate predetermined operation button (74, 740) or kind of switch is further provided so as to select the automatic excavation function, so that an automatic excavation performance selection signal is input into a control unit (70, 700) in operation c) (S300).

11. The method of claim 8, wherein when the automatic excavation of the construction work apparatus is not performed in operation e) (S500), the method returns to operation c) (S300) of selecting the automatic excavation function of the construction work apparatus.