Research On The Design And Vibration Analysis Of A New Type Of Hydraulic Elevator System

Proportional pressure and flow compound valve is widely used in hydraulic system of injection molding machine,and the compound valve not only controls the pressure of hydraulic system but also controls the speed of the implementation of components. The compound valve has the advantages of low energy consumption, and the compound valve with the function of energy saving. At present, most of the hydraulic elevator of the speed control system is proportional throttle valve control technology, and the bypass throttle speed regulation control method compared with the throttle valve control system has the advantages of energy consumption is relatively low, but the system itself has a small speed range and high flow pulsation, and with the increase of throttle opening the load capacity is reduced. The throttle control system has a larger energy loss, but the system itself has a high stiffness, and flow regulating with advantages of wide range, and the system can reduce the elevator starts impact. In this paper, in order to solve the problem of the throttle control system had high energy consumption, the proportional pressure-flow compound valve with the function of energy saving was applied in the system of hydraulic elevator as the main valve to control uplink of the elevator. The main control valve in hydraulic elevator system mainly depends on the special valve imports from abroad for hydraulic elevator, and the price is expensive, and greatly increases the cost of the system. Research on the new type of hydraulic elevator system to reduce the cost of the elevator has great significance for the development of the elevator. Hydraulic elevator as mechanical and hydraulic coupling, the vibration phenomenon of the elevator is inevitable. However, the vibration of hydraulic elevator is often ignored. In this paper the vibration characteristics of the hydraulic elevator was studied, and to provide a theoretical basis for reducing the vibration of elevator.By all accounts, this paper put forward the scheme of hydraulic elevator system based on proportional pressure-flow compound valve had been redesigned, and the main components of the system in the selection and calculation. Simulate the hydraulic system with AMESim in the hydraulic simulation platform. The simulation results show that: when the elevator uplink, the outlet pressure of the hydraulic pump could produce corresponding change according to the size of the load, reducing the loss of overflow in the elevator load is low, and with the energy-saving effect. The proportional pressure-flow compound valve to control the flow of the hydraulic system had better stability and less affected by the change of load, so as to ensure the stability of elevator running speed.In this paper, the vibration characteristics of the hydraulic elevator based on the construction of laboratory were studied, and the physical model was simplified, and set up the vibration model of 2 degree of freedom. Focus on the analysis of the impact of changes in the bottom rubber shock pad stiffness and the oil stiffness and the load of the car on the natural frequency of the system. Analysis the vibration responses of the car in the inertial force and the oil pressure fluctuation excitation. The simulation results show that: Along with the elevator rises, the equivalent stiffness of the oil will reduce, leading to the natural frequency of the system decreased. Increase the load of the elevator car will lead to reduce the natural frequency of the system. The stiffness of the car bottom rubber shock pad increment will make the natural frequency of the system increases. The vibration response of the car is large in the starting and braking process, but reasonable choice of the elevator car speed curve can reduce vibration response. In order to avoid the system to vibrate in resonance with the excitation of fluid pressure pulsed, external excitation frequency should to avoid the natural frequency of the system.In summary, this paper makes a detailed study on the hydraulic elevator system based on proportional pressure and flow compound valve, and put forward a new solution to energy loss problem of the throttle speed regulation hydraulic elevator. The simulation experiments was carried out on the dynamic characteristics of the hydraulic elevator, and research on the system in the case of external excitation, the movement rules of the vibration of the system, and provide a theoretical basis to solve the vibration problem of the hydraulic elevator.