Bending stress analysis of eccentric straight and helical curve-face gear pair

To promote the engineering application of composite transmission of high speed curve face gear, which consists of a cylindrical gear and a high speed curve face gear, the analysis of tooth bending stress should be taken into consideration. High speed curve face gear pair is a new type of curve face gear pair. Combined with the principle of high speed cam and curve face gear pair transmission, it can transfer the axial/rotation composite motion and power between two intersecting shafts. Based on the gear engagement principle, the gear meshing coordinate system was established and the fundamental of the high speed composite transmission was expounded. Combined with the tooth profile equation of generating gear, the tooth surface equation of high speed curve face gear was gained. Tooth force, contact ratio and normal load distribution were calculated. Then the tooth bending stress of high speed curve face gear during the transmission was calculated and analyzed in detail. Influence of basic parameters on tooth bending stress was discussed. Finally, the simulation and measurement experiment of tooth bending stress was carried out. By the comparison analysis of simulation, experiment and theory, the correctness of tooth bending stress calculation method was verified, which has important guiding significance for the further research of high speed curve face gear of composite transmission.

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Study on the compound transmission mechanism of the curve-face gear based on screw theory

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406217730092 ◽

2017 ◽

Vol 232 (17) ◽

pp. 3115-3124 ◽

Cited By ~ 1

Author(s):

Chao Lin ◽

Yanqun Wei ◽

Zhiqin Cai

Keyword(s):

Screw Theory ◽

Transmission Mechanism ◽

Tooth Surface ◽

Design Parameters ◽

Gear Pair ◽

Face Gear ◽

Cylindrical Gear ◽

Cam Mechanism ◽

Conjugate Surfaces ◽

Curve Face

The compound transmission mechanism of curve-face gear is a new type of gear transmission based on the cam mechanism and the curve-face gear pair. It combines the transmission characteristics of the cam mechanism and noncircular bevel gear. When the compound transmission mechanism of curve-face gear is engaged in the meshing transmission, the rotating center of the cylindrical gear is fixed and used as the driving wheel, and the curve-face gear can generate the helical motion around the axis. In this paper, the meshing characteristics and motion laws of the compound transmission mechanism of the curve-face gear are studied based on the theory of screw. Based on the meshing theory of gears, the coordinate system of conjugate surfaces is established, the basic meshing theory and equation are obtained. On this basis, combined with the principle of the cam, the transmission principle is analyzed by the screw theory. The tooth surface equation of the compound transmission mechanism of curve-face gear is deduced based on the meshing theory and the related knowledge of geometry. The motion law of the curve-face gear and the change of the motion law with the change of the basic parameters of the gear pair with different design parameters are calculated and analyzed. An experimental platform is built to verify the law of motion, and the experimental results are compared with the theoretical values. The correctness of the theoretical analysis is verified, which provides a new way for the research of the compound transmission mechanism of the curve-face gear.

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Contact fatigue model and life prediction of the compound motion curve-face gear pair

Transactions of the Canadian Society for Mechanical Engineering ◽

10.1139/tcsme-2019-0202 ◽

2020 ◽

Vol 44 (3) ◽

pp. 440-451

Author(s):

Chao Lin ◽

Peilu Li ◽

Chunjiang He ◽

Qingkun Xing

Keyword(s):

Fatigue Life ◽

Crack Growth ◽

Contact Fatigue ◽

Tooth Surface ◽

Gear Pair ◽

Face Gear ◽

Fatigue Model ◽

Contact Fatigue Life ◽

Five Axis ◽

Curve Face

Different from the common face gear pair fixed rotation motion between intersecting axes, the compound transmission of the curve-face gear is a new motion form, which can convert rotational motion into rotation and movement motion. To solve the contact fatigue life problem of this new motion form gear pair, a new contact fatigue life calculation method of the compound transmission curve-face gear pair was proposed. Based on the space gear engagement principle and the fracture mechanics theory, the theoretical contact fatigue model of the curve-face gear composite transmission was established. Considering that the contact load for every tooth is time-varying in the half-period of the curve-face gear, the contact fatigue life stage of the curve-face gear was divided into crack initiation and crack growth, and the crack growth fatigue life for each tooth was calculated using the finite element method. The curve-face gear pair was processed in the five-axis NC machining center and the compound transmission experiment platform of the curve-face gear was set up to measure the tooth surface dynamic contact stress, and the overall life of the curve-face gear was predicted. The comparison analysis between theoretical and experimental results verified the correctness of the theoretical contact fatigue calculation model.

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Characteristic analysis and application of composite motion curve-face gear pair

Journal of the Brazilian Society of Mechanical Sciences and Engineering ◽

10.1007/s40430-015-0432-3 ◽

2015 ◽

Vol 38 (6) ◽

pp. 1797-1804 ◽

Cited By ~ 13

Author(s):

Chao Lin ◽

Yi Liu

Keyword(s):

Gear Pair ◽

Characteristic Analysis ◽

Face Gear ◽

Curve Face

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Research on the Discrete Algorithm of Tooth Surface for a Curve-Face Gear

Journal of Mechanical Design ◽

10.1115/1.4044434 ◽

2019 ◽

Vol 142 (5) ◽

Author(s):

Zhiqin Cai ◽

Chao Lin

Keyword(s):

Gear Tooth ◽

Theoretical Data ◽

Surface Characteristics ◽

Tooth Surface ◽

Gear Pair ◽

Face Gear ◽

Distribution Law ◽

Discrete Algorithm ◽

Generating Method ◽

Curve Face

Abstract The curve-face gear pair is a new type of face gear pair with a variable transmission ratio. Concerning the complexity of its tooth surface, based on the coordinate transformation principle and the spatial meshing theory, a discrete algorithm of this tooth surface was proposed. The determination rule of the limiting points on the tooth surface was analyzed by introducing the generating method and tooth surface characteristics of this gear tooth. Through the corresponding limiting angles and the distribution law of the contact line, the gear tooth surface was discretized, and the theoretical data points of the tooth surface were obtained. The variations in gear tooth surface in a meshing cycle and under different parameters were analyzed. By comparing the virtual tooth model and the corresponding rolling experiment, the correctness of the tooth surface discrete algorithm of the curve-face gear was verified.

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Compound transmission principle analysis of eccentric curve-face gear pair with curvilinear-shaped teeth based on tooth contact analysis

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/09544062211047075 ◽

2021 ◽

pp. 095440622110470

Author(s):

Chao Lin ◽

Yu Wang ◽

Yanan Hu ◽

Yongquan Yu

Keyword(s):

Axial Direction ◽

Contact Analysis ◽

Gear Pair ◽

Face Gear ◽

Tooth Contact Analysis ◽

Tooth Contact ◽

Contact Points ◽

Tooth Surfaces ◽

Set Up ◽

Curve Face

A new type of compound transmission gear pair was put forward, called eccentric curve-face gear pair with curvilinear-shaped teeth. It could realize reciprocating motion of the gear shaft when the intersecting shafts achieve transferring motion and power through its unique tooth profile. The compound transmission principle of this gear pair was fully established based on the profile-closure process of axial direction and meshing process of the end face. The tooth surfaces of the eccentric curve-face gear and non-circular gear were generated. The contact paths of different teeth were obtained, and the compound transmission principle of eccentric curve-face gear pair with curvilinear-shaped teeth was verified by tooth contact analysis. By analyzing the mechanical characteristics of time-varying contact points, the changing rule of contact force was studied, and the compound transmission principle of the gear pair was further revealed from mechanics. Moreover, the experimental platform for transmission of eccentric curve-face gear pair with curvilinear-shaped teeth was set up to measure the motion law and contact area, and the correctness of the analysis results was verified.

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