Research On A New Type Of The Protective Device For Diesel Engine Guards Against The Run Away Slip

During the working process of diesel engine of the diesel locomotive, the accidental factors, such as improper operation or mechanical breakdown of oil supply system, could result in the run away slips. Although this kind of slips are not very many during the locomotive utilization process, actually it creates the extremely serious consequence. Once the breakdown occurs, not only creates the economic loss, moreover creates the machine broken accident of utilization on-line, thus affects the railway transportation seriously. Therefore, installing the completely independent controlled protective device reasonably in the diesel engine to enhance the security of diesel engine is extremely important.This paper analyses the reasons of run-away faults , compares the protection methods and proposes this plan of installment technology on the basis of earnest studies and comprehensive investigation. Taking the monolithic processor control as a foundation, this paper is divided into five parts. They are: signal gathering of rotational speed, speed measurement and the overspeed judgment link, the implementing organ, the rotational speed digital revealing electric circuit and the power source. When the diesel engine rotational speed achieves the rated speed, this equipment will cut-off the electric circuit of fuel feed pump, stop feeding, and sweep the excess oil in the connection of high pressure oil pump rapidly with the compressed air. By this way, no oil enters the air cylinder, and forces the diesel engine to decelerate, and close down.In order to examine the actual effect of protective device of diesel engine which this paper designs, we has successively carried on the high-pressured oil pump test platform simulation test, the indoor simulation test, the simulation experiment of complete machine in water resistance and the function and examine experiment of model machine, obtained the satisfactory result. This equipment has the quality of simple structure, easy to install, modifying not in a big way to the original circuitry and oil duct. As the add-on component of original overspeed trip, it has automatic control depending on the electrical signal, does not need the driver to intervene, does not increase the extra burden which the train attendant operates, therefore prevents the diesel engine run-away accident effectively, thus avoids the harm which creates to the diesel engine and the auxiliary drive and to the influence which transports produces.