1、The research and Application of electro-hydraulic control technology With the coal mining technology going forward, the control system of hydraulic support and materials have been greatly improved. The control system from manually operated the to automatic control for electro-hydraulic gradually and
2、 accelerated the advancing velocity of working face greatly. In addition, Development and application of high strength steel also further reduce the quality of support working resistance of unit, support performance has been greatly improved, so that the face yield increased exponentially. Automated
3、 mining working face and become a major reform of coal mining technology. At present, the electro-hydraulic control technology has been widely used in the USA, Germany and other countries fully mechanized mining technology and China is only in recent years gradually in some hydraulic support Combine
4、d with the use of electric and hydraulic control technology.Key word:Hydraulic support; The electro-hydraulic control system; Design and application1 the basic principle of the electro-hydraulic control technology and main components1.1 The basic principle of the electro-hydraulic control technology
5、(1) Bidirectional adjacent control systemFully mechanized working face of each frame are provided with frame control box, the operator through the support frame control box to select the adjacent control, And then sends out the corresponding control command according to instructions. The electromagn
6、et adjacent frame corresponding or micro-motor take action and make the electric signal into a hydraulic signal. the main control valve opened and for the fluid to the hydraulic cylinder, finally it achieve adjacent bracket corresponding action. Support status by the displacement sensor and pressure
7、 sensor feedback to the frame control box and frame control box according to the feedback signal of the sensor bracket decided next action.(2) Bidirectional group control systemThe working face of the bracket is divided into several groups, then in this group, the first support by operator press a b
8、utton to control box and sends a command. When moving is completed it automatically sends out the control signal to a control box, then the next take action. By analogy, it realizes the automatic control of group.(3) Automatic control system of the working face The electro-hydraulic control system w
9、ith perfect function is provided with a main control console, an infrared device, it can realize the control of full face automatic linking bracket with the coal mining machine. The principle is: each bracket frame control box is connected to the main console network, when the position signal suppor
10、t infrared receiving device receives the shearer emitted by the infrared emitter, feedback to the main console, console feedback signal according to the instructions of the support, make the corresponding take action. 1.2 The main composition(1) Electro hydraulic controllerElectro hydraulic controll
11、er is the control system of the heart, it consists of microprocessor, information transmission unit, a keyboard and a data receiving device. Electro hydraulic controller has two functions: one is according to the operation instruction and scheduled completion on-off solenoid valve group, then contro
12、l the support column, Jack action, on the other hand it also received support measured (including pressure, displacement, etc.) and to analyze and judge, and then control support action, and show the support parameters and support fault.(2) Electro hydraulic control valve groupControl valve is an el
13、ectromagnetic valve control hydraulic a versatile, can replace the liquid circulation selection valve, the valve assembly with a pressure switch to support the action of the valve group and surveillance support working conditions, according to the instruction of opening or closing the valve channel
14、controller.(3) The center consoleThe system according to the user to determine the level of automation work surface height to decide whether to use MCU. Install electrohydraulic controller, even do not need to install the ground of central control room (MCU1) and the underground control room (MCU2),
15、 also can realize the full automation. Control system of the lowest level is bi-directional adjacent single control, it is a common one control four system, and then extended to automatically sort,group control, group process and the combination functions, these do not need the center console. (4) A
16、uxiliary componentsThe electro-hydraulic control system can measure stent, and the hydraulic parameters into the original pressure electronic signal sensor, it reflect the contact sensor Jack stroke position and for infrared automatic start shearer remote control hydraulic support electrohydraulic controller receiver etc. All the sensors have the respective output signals, which can find out the interruption position, and each bracket elect
