To grind special-shaped screw rotor and evaluate the grinding precision of rotor ground
a method of segmented computer numerical control(CNC)grinding wheel dressing is proposed
and the segmented interval determining scheme is given. According to the tangent condition between grinding wheel surface and rotor helical surface
the contact line equation is deduced. The grinding wheel profile can be calculated by the condition line equation and rotor profile. Several grinding wheel profiles are obtained by different installation angle and center distance on the same rotor profile. The results show that the installation angle is a sensitive parameter and the error within 1 μm results from changed center distance of 1 mm. The reasonable center distance interval of segmented CNC grinding wheel dressing method ought to be less than 1 mm. The test is carried out on a SK7032 grinder for a female rotor
and the machining error can be controlled within ±10 μm with the method of grinding wheel segmented dressing.
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