A novel desktop device for lapping thin-walled micro groove

摘要

This paper presents a novel desktop device for lapping thin-walled micro groove of a specimen used in optical equipment, the device is aimed to remove metamorphic layer (about 1 μm thick) formed on the groove's upper surface as well as ensure its thickness accuracy. It adopts the way of macro/micro motion combination, the macro-motion table uses stepper motor and ball screws to realize motion in large stroke, high speed and the micron level positioning, the micro-motion table uses the electrostriction appliance to actuate the flexible four bars mechanism to realize the small stroke, low speed, and the submicron level positioning. The system uses the strategy of two ways of feedback, the macro/micro motion table uses the precise linear grating as close-loop position feedback, and the sensing holder uses the eddy current transducer as the force and deformation feedback of the elastic fixture. The most novel aspect is the first proposed idea of realizing automatic feeding by elastic recovery of the fixture, whose structure has been delicately designed. In order to ensure small lapping force and relatively high natural frequency, both static and modal analysis of the fixture has been done by ANSYS, the results was in good accordance with experiments. Lapping experiments have showed that this device can remove metamorphic layer efficiently as well as obtain good surface quality at the same time.