Research On A Novel Indexing Table Based On Ultra-precision Gear And Worm Drive

The indexing table is widely used in the field of mechanical processing and testing,and it is an indispensable part of many precision equipment.When processing various indexing elements,such as gears,worm gears,polyhedral prisms and other parts with various specifications,the indexing accuracy of the indexing table directly affects the accuracy of the parts being processed.The common core indexing elements of indexing table are worm wheel,gear rack,groove wheel,indexing disk,end gear disk and direct drive motor.At present,these types of indexing turntables are difficult to meet the industrial needs of high accuracy,strong anti-interference ability,continuous indexing and high cost performance.Aiming at the problems of the existing indexing table,a novel type of indexing table based on high precision standard gear and worm drive is developed,and the influence of the precision of the key parts of the indexing table on the indexing accuracy is analyzed.The mathematical model of the relationship is established,between the installation errors of key parts and the accuracy of dividing in the meshing process of worm and standard gear.The high precision dense bead shafting structure is adopted to ensure the rotation accuracy of the shafting to the greatest extent.The meshing clearance eliminating mechanism of worm and high precision standard gear is developed to ensure multi-tooth surface continuous transmission of indexing mechanism of indexing table,and further reduce the influence of indexing error of standard gear itself on comprehensive indexing accuracy of turntable.The end sliding shafting structure with shock absorption function is proposed for high precision positioning and support of indexing table.A highly sensitive micro-displacement error transfer lever device is developed for the high-precision standard gear indexing error measurement.The indexing error of the standard gear itself is 4.93?,which is obtained by grouping measurement method.In this paper,the comprehensive indexing accuracy of the indexing table is calibrated by a fully integrated method which can separate the measurement system errors,and the final indexing accuracy of the indexing table is 1.76?± 0.65? by error compensation.A novel indexing table based on high precision standard gear and worm drive is developed in this paper.It overcomes the disadvantage that the end gear indexing plate can not index continuously,realizes continuous indexing at any angle,and has the advantages of compact structure,high indexing accuracy,large load capacity and low cost.It can be used in precision machining and testing of standard gears or other indexing elements of reference level,and has good market application prospects.