Modified geometry of spur gear drives for compensation of shaft deflections

Abstract

One of the greatest concern of spur gears is the edge contact of tooth surfaces that is caused by misalignment of the gear drive. Such a misalignment is caused partially by the deflections of the shafts where the gears are mounted. As a result of the edge contact a non favorable condition of bearing contact is achieved, providing a high level of contact and bending stresses. An intensive research and many practical solutions have been directed to modify the gear tooth surfaces in order to avoid edge contact. An innovative procedure is proposed here for: (i) determination of the errors of alignment at the gear drive caused by shaft deflections, (ii) incorporation of such errors of alignment in the generation process of spur gears for compensation of shaft deflections, and (iii), determination of a favorable function of transmission errors for the design load. A finite element model of a spur gear drive including pinion and wheel shafts is used for the determination of the errors of alignment along the cycle of meshing. Compensation of misalignments in gear generation is then accomplished by modification of pinion tooth surfaces whereas the wheel tooth surfaces are kept unmodified. Additional modifications of pinion tooth surfaces may

Analysis of the Effect of the Addendum Modification Coefficient for Contact Surfaces of Spur Gear

“…The appropriate adoption of the necessary coordination systems and the finite element mesh [13,22,23] is the main important determining parameters for the TCA analysis [7,8,9,13]. For this analysis three coordination systems have been adopted [9,10]:…”

Analytical determination of basic machine-tool settings for generation of spiral bevel gears and compensation of errors of alignment in the cyclo-palloid system

“…Such data were derived in [15] for spiral bevel and hypoid gears produced either by face-milling or facehobbing. Determination of blank data from basic data such as the power to transmit, the gear ratio, the pinion speed, the shaft angle, and the quality of gears, can be based as well on the application of Standard ANSI/AGMA 2005-C96 [8] for the case of spiral bevel gears produced through the cyclo-palloid system.…”

“…Regarding the position of the pinion (or the gear) in the cutting machine, the basic machine-tool settings are set as follows (see [15] to identify nomenclature and settings):…”

“…In the present paper, an analytical method for machine-tool settings correction in order to compensate errors of alignment due to shaft deflections is proposed. Procedures for compensation of shafts deflections have been proposed in [15] for spur gear drives and in [16] for spiral bevel gears generated by face-milling.…”

Computerized generation and simulation of meshing of a novel crown gear coupling avoiding edge contact

“…However, no research has been found on how to avoid the occurrence of the hub tooth tip edge contact with the sleeve tooth root flank and the sleeve tooth tip edge contact with the hub tooth root flank. Edge contact results in unexpected early failure of a gear transmission because of highly concentrated contact stress generated between the tip of one member and the root flank of the other (Litvin et al, 2003;Gonzalez-Perez et al, 2015;Fuentes-Aznar et al, 2017;Guo et al, 2019). And, the same is true for the crown gear coupling.…”