Unformatted text preview: racts clearance hk = ht c The width of the tooth measured in axial direction (spur & helical) The smaller one of two mat ing gears The larger one of two mating gears Measured on the pitch circles, shortest distance between non contacting surfaces o f adjacent teeth increases as center distance increases; so me backlash necessary to allow room for oil film under condit ions of both thermal expansio n and contraction; excessive backlash increases no ise, and impact loading (when torque reversals occur) Addendum Dedendum Clearance Clearance circle Whole depth Working depth Face width Pinion Gear Backlash a b c ht hk FW CONJUGATE ACTION o One essent ial fo r correct ly meshing gears is t hat t he size o f t he t eet h (t he mo du le) mu st be t he same for the two gears. o Ano t her requirement t he shape o f t eet h necessar y fo r t he speed ratio to remain const ant during an increment of rotation; this behavior of the contacting surfaces (i.e. the teeth flanks) is known as conjugate action. o Line o...
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- Fall '09
- gear, po int, pitch diameter, ang le, Pitch circle Pitch