Modeling And Research On Tire Dynamic Balancing Device By Amplitude Method

Tire dynamic balance testing device is used to quantitatively measure the size and phase position of the equivalent unbalance mass. The measuring result is applied to mark the phase position of tire's static unbalance and grade tire produces. The tire manufacturers can find the problems in the production process according to the measuring result. There are many factories manufacturing tire dynamic balance testing device at home and abroad. However, the product quality is uneven. The measuring results of a tire tested by various devices are different, which causes confusion in market.In this paper, aiming at the improvement of tire dynamic balance testing system, set up to the system of the displacement amplitude as the input variables, unbalance mass of the tyre for multi variable mathematical model of output variables, by laser non-contact measurement method is used to obtain the displacement signal, using phase locked loop technique and photoelectric switch instead of the rotary encoder and the method to improve the test system stability, sensitivity and real-time have good role in promoting.The main contributions in this thesis were as follows:(1) The tire equivalent unbalance mass was analyzed based on the correcting principle of the wheel dynamic unbalance. The structural composition of tire dynamic balance testing device was introduced. On those basis, the dynamical model of the testing device, which is the mathematic relationship between the equivalent unbalanced mass on tire's correcting plane and dynamic load, was built. The error sources of measuring results were analyzed.(2) Improved tyre dynamic balance test device support structure, sensor type and connection mode, establish tire equivalent unbalance dynamics model and the measuring point displacement between signals. On this basis, the extraction of displacement frequency signal were analyzed, and dynamic model of coefficient calibration method(3) Based on tire dynamic balance testing machine. The working principle, structure and function, using the embedded system implementation for multiple variable displacement measurement and synchronization logic sequence, using photoelectric switch and PLL technology alternative rotary encoder to improve measurement system and the real-time processing capability.(4) In the light of the dynamic imbalance signal strong periodicity and accompanied by strong background noise, self-correlation analysis hierarchical threshold de-noisingmethod using wavelet detail coefficients, in tyre dynamic balance test system in practical application were studied.