Mechanical Analysis And Modeling Of Tire Dynamic Balance Testing Device

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. Aimed to explore a method to improve device’s stability, sensitivity and accuracy of the measuring result, on the basis of engineering application, the mechanical property of tire dynamic balance testing device was deeply studied. The supporting structure, the type and installation of the sensors were reconstructed. The dynamical model of the reconstructed testing system was developed. 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) Gravity and the force imposed on the belt pulley of the testing device were studied. With the help of modeling technology by SOLIDWORKS software, a three-dimensional model of the testing device was established. Static analysis and model analysis of the device were carried out by ANS YS software. The analysis results showed that the gravity and the force imposed on the belt pulley had a great effect on the accuracy of measuring results. A method of balancing the gravity and the force using suspenders and bars was put forward. Upon the analysis of the performance requirement of the suspenders and bars, the design standard of parameters was built. The rationality of the design was proved using FEA. The results showed that:After installing logical suspenders and bars, total deformation of the device reduced by 88.92%. End jump decreased by 93.6%. The biggest equivalent stress reduced by 90.67%. The first natural frequency had a 15.58 percent while the second natural frequency just raised by 1.34 percentage points. The accuracy of measuring results was improved while the effect on the sensitivity of the device could be neglected.(3) The supporting structure, sensor type and its installation were reconstructed. The mathematical relationship between tire equivalent unbalanced mass located on correction plane and displacement signal was analyzed. On this basis, the fundamental signal extraction method was researched.(4) Further analysis of the performance requirements and structural parameters of the supporting structure were carried out. The model of supporting structure for device with a 600rpm testing rotational speed was established. Static analysis and vibration characteristics analysis of the whole device were implemented. The results showed that: the end jump was 0.013mm less than 0.02mm. The testing frequency was 0.481 times bigger than the first resonant frequency, however, the testing frequency was merely 0.081 times as big as the resonant frequency. The sensitivity of the device was significantly improved which was in favor of boosting the measuring results’accuracy and precision.