Application Research Of Visual Inspection In Assembly Of Internal Components Of Tapered Roller Bearings

The inner component of the tapered roller bearing is composed of the inner ring of the bearing,the cage and the tapered roller.As the core component of the tapered roller bearing,its performance directly determines the working performance and service life of the whole mechanical equipment.Whether the components inside the tapered roller bearing have roller inversion or leakage defects and the positioning accuracy of the cage directly affect the product quality of the inner component.With the continuous improvement of the level of automation,the traditional detection and positioning methods have been unable to meet the needs of automated production.In order to realize the automatic detection of the components to be tested and the precise positioning of the cage,this paper uses LabVIEW as the development platform to study the roller flipping,missing defects and the visual positioning method of the cage in the tapered roller bearing by means of machine vision.The system realizes the positioning of the cage while judging whether there are roller flipping and missing fitting defects in the inner component of the tapered roller bearing.The main contents include:Firstly,a visual inspection algorithm for roller flipping and missing installation of tapered roller bearing inner component is proposed.Comparing the qualified inner component with the inner component with roll inversion and leakage defects,the main difference is that the rollers are distributed in the ring zone,and the middle line of the ring is used as the characteristic information to judge whether there are roll inversion and leakage defects in the inner component.Firstly,feature information is extracted by image preprocessing and segmentation techniques.Then,in order to facilitate the analysis of feature information,the center line of the ring is expanded by coordinate transformation,and its gray value distribution is counted and the waveform of feature information is drawn.Finally,the waveform analysis is used to judge whether there are rollers inverted or leakage in the inner components.Then,a cage vision localization algorithm is proposed.The gray image of the shrinkage die is acquired,and the center of the shrinkage die is determined by rough and precise quadratic fitting method.The circumferential position of the shrinkage die ridge is used as the positioning datum of the cage.According to the characteristic information of the inner component,the deflection angle between the beam of the inner component to be measured and the reference position of the shrinkage die is determined.The eccentric angle is used as the correction angle of the cage positioning,and the servo control system realizes the positive position of the cage.Finally,the development of visual inspection and location system for inner components of tapered roller bearings has been completed.A large number of experiments show that the system can accurately detect the flip-chip and missing defects of the roller,and the positioning accuracy of the cage can reach ±0.6mm,which meets the requirements of detection and positioning.Moreover,the system can effectively solve the problems of low detection efficiency and poor reliability of the existing detection methods.