The paper mainly researches the application of advanced PLC (Programmable Logic Controller), transducer, and absolute encoder in the grab bucket crane, which takes the place of the traditional mode of the electric control and aims to improve the work efficiency of grab bucket crane and decrease its failure rate. These applications will bring a lot of advantages, such as lower maintenance costs, lower workload of maintenance, and easily to be manipulated etc. It is also achieved to be semi-automatic operation to reduce the risk of man-made operation accident with the effects ofreliablerunning and energy-saving.
The paper primarily focuses on the principle of automatic open / closegrab ofgrab bucket crane and proposes the principle and physical significance of the movingcoordinate method. It is practical that the applied absolute encoder automatically follows the lifting and landing of grab bucket and measures the length difference value of steel wire rope to achieve the function of its automaticopening or closing and stable grabbing. According to the usual failures during the practical application of grab bucket crane, the failure display is also developed to be applied to the crane.
The paper consists of four parts:
The first part (Chapter one: Introduction) mainly describes the working principle of grab bucket crane, focusing on the problems of crane controlled in the traditional method, and further exploring the feasibility for intelligent implementation of grab bucket crane.
The second part (Chapter 2, 3, 4) describes the configuration and functionalprinciples of PLC, transducer and encoder. It also makes a theoreticalanalysis for the selection of PLC, transducer and encoder, which lays a theoretical foundation for the realization of the intelligent operation of grab bucket crane in the following chapter.
The third part (Chapter 5) researches the specific schemes for intelligent implementation of grab bucket crane, such as heavy trolley, light trolley, controller configuration, PLC, transducer, electric connection of absolute encoder, working principle etc. It explicitly explained the principle of automatic open/ close grabbing of crane and the implementation of stable grabbing. It also introduces the realization principle to substitute the limit position of ascending with the utility of encoder.
The fourth part (Chapter 6) mainly introduces soft structure of intelligent operation and PLC configuration of gab bucket crane. The software program of heavy trolley, light trolley, andswitching & hoisting mechanism is also composed in the paper.
In the end, it is summarized for the whole research and makes an outlook for the future research.
