Study On Automatic Control Cooling Device Resisting Braking Performance Heat Fade Of Truck

In order to solve braking failure because of braking performance heat fade of brake drum. In my thesis I has designed cooling ability automatic control device.Based on traditional(water cooling), this design regulateds Rotating Speed of direct current dynamic(pump which is driven by PWM to chang streamflow), according to detected friction lining temperature signal, The PWM signal can be generated by AT90S8535 the Single Chip Microcompute, to regulate cooling capacity. This system does not use automobile power, overcomes some disadvantages of traditional system, using direct spray to cool surface of brake drum improves the vacuum cooling process, and cool effect, reduces water consumption, prevents the hot decay of brake drum, improves the braking performance, improves automation degree, reduces accident's rate, enhances driving security.In this paper, the performance of heat from the brake mechanism of a recession, the analysis of the brake heat exchanger and heat balance of the process and come to lead to recession the three factors in the braking performance heat ANSYS simulation in combination with cooling, quantum chemistry calculation in heat and cooling on a quantitative basis, the trial has played a guiding role.A pilot basis, focusing on motor-driven pump to carry out the selection and matching design, omizing nozzle design and PWM pulse occurred in the design process, as well as the main factors for a trial design; In order to improve driving safety, to carry out automatic control design , the motor-driven pump from the single-chip microcomputer chip in accordance with the temperature of friction servo signal to control the servo controlled pump water pumpage to automatically adjust the cooling capacity and reduces the probability of past human misoperation. The issue also designs control system hardware and software, including: the overall design of the cooling control system, control system hardware design and selection, control system software design.Lead to a recession under the heat of the three main factors, carried out experimental design, respectively, under different initial braking speed and load under three different temperature of the brake temperature rise stage test. Cooling simulation using ANSYS analysis of the outer surface of brake drum cooling method is effective and feasible in different water flow under the simulation of evaporative cooling, and with the great flow of cooling were compared,to draw traffic and the relationship between flow and the cooling effect.The tests indicate that: the cooling device can be effective for cooling of the brake drum to prevent high-speed braking, or as a result of overloaded vehicles braking performance heat-induced recession in the occurrence of the phenomenon, and the convenient and flexible installation of cooling systems, small tanks, higher automation and less cost advantages .The cooling system in vehicles equipped with drum brakes in the promotion of use will be greater economic and social benefits.