Development Of Composite On-line Test System For General Purpose Engines

Engine has a history of over a century in other countries, now the annual engine production output throughout the world is tens of millions sets. At the early development stage, production of general purpose engines is like that of motor cycle engines, which mainly involves manual handling and assembling. With the growth of production output, the assembly line is adopted, but as test of engines involves starting of engines and loading of them, the problems like exhaust ventilation, connection of output power, power consumption, and operation safety have to be solved, generally the solution to these problems is to take the engine off from the assembly line and test it in a separate engine test room; this solution is far from satisfactory because it involves a high labor intensity, a long test cycle, a big number of test devices and equipment, a big quantity of labor, and a large space. The development of modern computer brings a revolutionary change to the traditional on-line test means, methods, devices and equipment. A kind of real-time automatic intelligent test and monitoring technology with computer as the core has gradually developed. Based on the actual level of power check devices for test of engines before they are off assembly line, it is capable of automatic identifying the product to be tested, automatic shift of test process software according to the product to be tested, automatic clamping of the product to be tested, automatic docking of the product and test device, automatic loading and testing, and saving and uploading of data to the manager. This system has performed with good results.This system researches a series of key technological problems, and integrates the traditional test method of the dynamometer in a test room with industry control technology, robot manipulator, information management and processing technology, to realize a high intelligent integrated and network-based multi-thread on line check and management control that can automatically schedule, identify, move, dock,, clamp and load the engines to be tested on the assembly line. Using ANSYS FEM software, the system researches and analyzes the shaft coupler's stress concentration and stress adaptability, and improves the shaft coupler's structure so that the shaft coupler's reliability and stability are improved; the system also researches the modal analysis of the general-purpose engine test bench, conducts the modal analysis and stress analysis for the shaft couplers that are very likely to break and produce an abnormal noise, so as to find and analyze the reasons of these problems. Using electronic load and excitation source to load the engine as controlled by the program, the system realizes the performance test on transient power, torque, rotation speed, fuel consumption rate, suction and exhaust pressure/temperature, etc., and can automatically save the report, manage information, exchange information between the operator and the machine, and produce the report as required, so that the work that used to require 4 persons now only needs one person and his pressing on the buttons of the control console, and the logistics process is also simplified because the random inspection has now be replaced by full inspection.