Unformatted text preview: f act io n (pressure line): t he co mmo n no rmal between t he t wo surfaces alo ng which t he fo rces at any instant are directed (frict ion contribut ion is neglected). o P it ch po int : t he int ersect ing po int between t he line o f cent ers and t he line o f act io n. The pitch point is fixed when conjugate action is sat isfied. ω2 /ω1 = (v2 / O2C)/ (v1 /O1C) = O1C.cosθ1 /O2C.cosθ2 = O1 C1 /O2 C2 = O1 P / O2 P = constant. This indicates that, since the centers are fixed, the point P is fixed too. 3 MECH323 – 2007 GEARS____________________________ o Pat h o f cont act is t he port io n o f t he pressure line t hat co nt ains all po int s o f toot h co nt act (between first and last points of contact) o P it ch circles are drawn t hro ugh t he p it ch po int fro m t he cent ers o f t he gears o Abso lut e value o f angu lar velo cit y ratio between two gears is inver sely pro port io nal t o t heir radii t o the pitch point, external meshing, the sign of the ratio is negat ive, meaning that the gears rotate in opposite direct ion, for internal meshing, the sign of the ratio is posit ive, meaning that the gears rotate in th...
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- Fall '09
- gear, po int, pitch diameter, ang le, Pitch circle Pitch