A measurement method for tooth surface errors of straight bevel gears based on 3D model

Self Cite

The accurate measurement of tooth surface deviation is an important prerequisite for the quality monitoring of high-precision spiral bevel gear. A measurement method for tooth surface deviation of spiral bevel gear is proposed based on one-dimensional probe, which can accurately measure and evaluate tooth flank. According to the forming principle of spiral bevel gear tooth surface, the theoretical surface is constructed as the measurement reference flank. A series of measures and methods are adopted to ensure the accuracy and correctness of one-dimensional probe measurement. These effective methods include the construction of the precise positioning of the gear blank and its surface, the measurement planning of reduction dimension which the gear needs to rotate once the normal angle after each point is measured, and the compensation for the increasing dimension of the one-dimensional probe. In addition, the minimization of the normal deviation of the tooth flank is achieved by using the optimum matching technique of the theoretical and the actual surfaces. The deviation degree of the actual surface relative to the theoretical surface can be accurately calculated and evaluated by establishing deviation model, which ensures the correctness for the evaluation result of the deviation. Finally, the test of tooth surface deviation is carried out on JD45 + gear measuring center using one-dimensional probe and Gleason 650GMS gear measuring center using three-dimensional probe, respectively. The measurement results show that the evaluation results of one-dimensional probe are in good agreement with those of three-dimensional probe. The proposed theory and method not only expand the measurement range of gear measuring center using one-dimensional probe, but also have certain reference significance for the precision measurement of other complex surfaces.

Section: Introductionmentioning

confidence: 99%

A model construction and measurement method for tooth surface deviation of spiral bevel gear based on a one-dimensional probe

Dai¹,

Li²,

Zhang³

et al. 2023

Self Cite

“…The FGA of complex tooth surface such as bevel gear can been accurately obtained, and the measurement accuracy and repeatability can also meet the engineering requirements. For example, Li and Dai et al [21][22][23] accurately completed the FGA acquisition of spiral bevel gear based on a one-dimensional probe, and the evaluation of the flank machining quality was precisely accomplished through comparing the measurement results of a three-dimensional probe.…”

Section: Introductionmentioning

confidence: 99%

An analytical method for the meshing performance of deviation surface of spiral bevel gear based on a one-dimensional probe

Li,

Dai,

Zhang

et al. 2023

Self Cite

The meshing performance is a significant indicator for evaluating the machining quality of spiral bevel gear. The flank contact accuracy (FCA) and flank geometric accuracy (FGA) are important aspects of meshing performance, and both are indispensable. In the actual production process, due to the lack of professional meshing performance analysis (MPA) software, the flank geometric structure cannot be reflected based on the FCA, and the actual meshing state cannot be reflected by the FGA, which cannot meet the manufacturing requirements of high-quality gear. Therefore, a MPA method for deviation surface of spiral bevel gear is proposed based on the gear measuring center (GMC) using a one-dimensional probe. By constructing the deviation surface, the flank meshing model is established, and the meshing parameters are determined. Aiming at the complexity of solving the meshing model, a method for decreasing the dimension of the meshing equations is proposed by establishing the mathematical relationship between the rotation angle and the normal vector, which improves the solution accuracy of the meshing point. The intersection points of the adjacent transmission error curves are taken as the meshing in and out points, and then the actual position of the contact pattern is accurately determined. The instantaneous contact ellipse is obtained by using the method of a cylindrical surface intercepting the deviation surfaces, which not only simplifies the solution algorithm, but also obtains the contact pattern more in line with the actual situation. Finally, the transmission error and contact pattern are digitally characterized. The experimental results show that the digital and actual patterns have good consistency. Flank geometry and gear meshing are organically linked based on the proposed method, and the actual meshing state can be predicted according to the flank topology deviation, which provides important theoretical support for the improvement of the machining quality and meshing performance of the spiral bevel gear.

Measurement and machining error assessment method for cycloid pump rotor profile based on STEP

Xu,

Xiao,

Dai

et al. 2024

The contour shape and machining precision of the rotor of an cycloid pump directly determine the sealing performance of the pump cavity. Precise measurement of contour machining errors is a crucial step in the manufacturing process. However, rotor contour curves are often designed by enterprises based on actual engineering needs, leading to inconsistency between the measured baseline contour and the designed contour, thus failing to accurately reflect the actual machining condition of the rotor. Therefore, this paper proposes a method for measuring the contour of the cycloid pump rotor and evaluating machining errors based on the STEP files necessary for product design in manufacting. Firstly, utilizing NX/OPEN API functions, contour coordinate points and unit normal vectors are obtained from the rotor's STEP design data. Subsequently, by planning the process of measuring the closed continuous contour of the rotor, the transformation between the workpiece coordinate system and the measurement coordinate system is achieved to position the tested rotor, followed by analyzing the influence of different starting points on error measurement and evaluation determines the optimal starting point. Finally, a measurement sampling point strategy is established to collect data points of the actual machining contour of the rotor. By achieving the best matching between the actual machining contour and the measured baseline contour, a contour deviation calculation model is established. Utilizing gauge blocks enables accurate assessment of pitch deviation, radial runout, and tooth-to-tooth distance deviation, resulting in assessment results that better fit the actual meshing situation of the rotor. Experimental results verifies consistency between the measurements of the one-dimensional probe and Gleason measurements. This theory and method not only expand the measurement range of the one-dimensional probe but also provide more accurate and efficient guidance for the flexible machining of the rotor.