AGMA 92FTM5-1992 pdf download.Main Advantages of Non-Involute Spur Gears: The Design of Non – Involute Spur Gears to Improve the Condition of Contact.
PARAMETERS TO ESTIMATE THE QUALITY OF A PATH OF CONTACT
The shapes of tooth flanks depend mostly on the shape of the path of contact and they are cindy related to the working capability of gears belonging to them. The working capacity of gears will be estimated with regard to damages occuning to gear teeth, which are o(two types, namely fractures and damages on the tooth flanks. Ractures usually appear on the root of the tooth and depend on tooth thickness and fillet radius. Both types of damages depend on a suitable shape of the path of contact. But this will not be the subject of this paper.
The damages on the tooth flanks are pitting and scuffing. If the oil-film of non-zero thickness exists between the tooth flanks then no damages arc expected.
To estimate the capability of gears, the following three mathematical criteria are used: Hertzian pressure for pitting. Dowson – Higginson equanon for oil-film thickness and Blok’s equation for scuffing.
In the continuation, there will be treated those influencing factors of the path of contact which affect results of the criteria from above. There will be also separately treated independent factors. The dependent factors will be used to set up the parameters for the estimation of the quality of the path of contact.
The Hertzian stress for the two cylinders of unequal diameter and similar material (steel) will be calculated (3):In this equation the factor Pred depends on the shape of the path of contact. If its value increases the Hertzian stress decreases.AGMA 92FTM5 pdf download.