Feeding of submillimeter-sized microparts along a saw-tooth surface using only horizontal vibration: Effects of saw-tooth pitch, vibration frequency, and humidity

We have previously shown that a saw-tooth surface with only horizontal vibration, simple planar and symmetric, can feed along microparts. The microparts move forward because they adhere to the saw-tooth surface more in the backward direction than in the forward direction. Previously, we studied the effect of the pitch of the saw-tooth surface and the vibration frequency on the movement of 2012-type capacitors (size: 2.0 times 1.2 times 0.6 mm, weight: 7.5 mg). In the present study, we investigated the movement of a smaller capacitors 0603-type capacitors (size: 0.6 times 0.3 times 0.3 mm, weight: 0.3 mg) and compared them with those of the larger capacitor. For the smaller capacitors, the fastest feeding was realized when the pitch was 0.05 mm and elevation angle was 20 deg. The smaller capacitors moved slower than the larger capacitors because the former were affected more by adhesion force. The feeding velocity of the smaller capacitor was affected much by the ambient humidity. In addition, the influence of ambient humidity for feeding was shown.