| With the rapid development of society and science and technology,elevators have become an essential vertical means of transportation in people's lives.At present:the munber of elevators in China has exceeded 6 million,and they still maintain a high growth rate.Traction elevator accounts for more than 90%of the total number of elevators in China:which is the most widely used elevator type.Balance coefficient is an important technical parameter of traction,elevator.Its change will cause the change of motor power,traction capacity:specific pressure of steel wire rope in rope groove and total mass of traction system which will affect the overall safety performance of elevator.Moreover:accidents caused by too small balance coefficient of elevator are common.Therefore:the State Administration of industrv has strengthened the balance coefficient of elevator Inspection work.In view of the shortcomings and limitations of the balance coefficient test method this paper carried out a.research on a general type of no-load elevat or balance coefficient measurement method.Starting from the definition formula of the balance coefficient of the elevator:combined with the influence of the traction ratio on the positive pressure of the traction wheel,this paper analyzes the pressure of the traction wire rope on the traction wheel and the specific pressure on the rope groove,and derives the friction formula.on the circumference of the traction wheel.Based on the analvsis of the influence of the static friction force between the traction wire rope and the traction wheel on the balance coefficient:a.general type of no-load elevator balance system is proposed The mea.surement method of number.In this method the static friction force is transformed into dynamic friction force by the way of moving up and down the car counterweight system.Since the car and counterweight have no change in mass:the dynamic friction force is equal in size and opposite in direction when running up and down:and the system friction force is eliminated by calculating addition:so as to obtain the elevator balance coefficient.According to the content of general-purpose method for measuring the balance coefficient of unloaded elevator:a set of general-purpose system for measuring the balance coefficient of unnloaded elevator is developed The system is mainly composed of two modules.The hardware part of the system is responsible for the movement,data acquisition and conversion of the lift car counterweight lifting of descending at a uniform speed and sending them to the upper computer,which is equipped with auxiliary devices and movable power supply.The system software is mainly Tesponsible for human-computer interaction and data processing,and based on SQLite embedded database,aiming at the infhuence of suspension device,compensation device and accompanying cable on balance coefficient measurement,the calculation method of system compensation correction is proposed.Through the comparison experiment with theoretical balance coeffficient and current method,the validity of the measurement method of balance coefficient of general-purpose unloaded elevator is verified;through the comparison experiment with the design value of the manufacturer,the advantages of high accuracy and eficiency of the measurement system are proved;through the repeat-ability and linearity experiment of the measurement system,the stability of the measurement system is proved.The general-purpose no-load elevator balance coeffcient measurement system greatly reduces the measurement time of the traditional current method for measuring the balance coefficient,effectively improves the working efficiency of the inspection agency or maintenance unit for measuring the balance coefficient of the elevator,reduces the cost of human handling and leasing transport weights,and has certain economic benefits. |
PDF Full Text Request