Vibration isolation characteristics and control strategy of parallel air spring system for transportation under abnormal road and eccentric load conditions

The precision equipment bears the vibration excited by the road roughness during transportation, and faces the risk of damage arising from the vibration. The parallel air spring vibration isolation system (PAVS) has an excellent vibration isolation performance, so has a good application prospect in the precision equipment transportation. But under the conditions of abnormal road and eccentric load, PAVS bears great vibration excitation, and the resulting large deformation of air spring makes the air spring stiffness nonlinear, so to obtain an excellent vibration isolation performance faces a great challenge. Aiming at this problem, based on the measured parameters, the nonlinear dynamics model of PAVS is proposed. Then, the influence of air spring under large deformation on the vibration isolation characteristics is discussed. Finally, under the condition of eccentricity of precision equipment, the vibration isolation characteristics of PAVS with equal height control strategy is investigated. The results show that PAVS with the equal height control strategy has good vibration isolation characteristics. So for the transportation of large precision equipment, PAVS is a potentially useful method.

ION-BEAM PROCESSING OF METAL MATERIALS FOR PRECISION EQUIPMENT

The tests have been carried out with the aim of determination of grinding and polishing of various materials with the help of ion-beam processing. The obtained results can be used of development of methodical and technological basics of ion-beam grinding and its application in precision engineering.

Analysis of the precision sustainability of the preload double-nut ball screw with consideration of the raceway wear

Ball screws are the driving components used to convert the rotational motion into linear motion in precision equipment. However, the machining accuracy of precision equipment is directly determined by the positioning accuracy of the ball screw. The authors analyze the precision sustainability of preload double-nut ball screws with raceway wear. A new wear model combining the modified Archard theory and the iterative interpolation method is established to analyze the variations in wear depth. A new model considering the coupling relationship between raceway wear and preload loss is proposed to study the precision life of the double-nut ball screw. In addition, a novel running test bench is designed to verify the precision sustainability of ball screws. The precision sustainability of the ball screw is analyzed during its life cycle, and these results match the theoretical values obtained by using the wear model.

STRUCTURAL METHOD FOR DETERMINING DEFORMATIONS BY GEODETIC MEASUREMENTS

Industrial equipment is a dynamic system that deforms during installation (assembly) and during operation. Under the influence of variable load and mixing of the center of gravity of the equipment and foundations on which it is installed, uneven horizontal and vertical displacements occur, therefore individual equipment elements are unevenly deformed, which can lead to poor performance or stoppage of this equipment. Timely measurement of the displacement of certain points of equipment (deformations) of precision equipment with the help of geodetic and other methods and their correct use for correcting the geometry of the equipment will contribute to improving the operational properties and increasing the period of uninterrupted operation of equipment’s, for example, precision conveyor lines for assembling cars.

Analysis of vibration isolation performance of parallel air spring system for precision equipment transportation

Precision equipment is usually accompanied with vibrations during road or railway transportation. Sometimes the vibration exceeds the given limit, leading to the damage of the equipment. It is necessary to control the vibration during the transportation. However, it is still difficult to adjust the parameters of a designed vibration isolation system for the transportation of different precision equipment under various road conditions. Aiming at satisfying the vibration isolation requirements of different precision equipment, this paper proposes a parallel air spring vibration isolation system based on the principle of limiting lateral deflection. According to the measured parameters, a rigid-body dynamics simulation model of parallel air spring vibration isolation system is established. Then its feasibility is verified, and the optimal parameters of the vibration isolation system are obtained by a simulation. Finally, the vibration isolation system is built and installed in the equipment to carry out the real vehicle transportation test. The test results show that the transportation vibration isolation system based on the parallel air spring structure has not only excellent vibration isolation efficiency but also acceptable lateral stability. The research results in this paper can provide a reference for the design of the vibration isolation system for the large precision equipment transportation.