Development of high accuracy classification system for small particles
Project/Area Number |
14550736
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
化学工学一般
|
Research Institution | Kyoto University |
Principal Investigator |
MATSUSAKA Shuji Kyoto University, Engineering, Associate Professor, 工学研究科, 助教授 (10219420)
|
Co-Investigator(Kenkyū-buntansha) |
MASUDA Hiroaki Kyoto University, Engineering, Professor, 工学研究科, 教授 (90026310)
|
Project Period (FY) |
2002 – 2004
|
Project Status |
Completed (Fiscal Year 2004)
|
Budget Amount *help |
¥4,000,000 (Direct Cost: ¥4,000,000)
Fiscal Year 2004: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 2003: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 2002: ¥2,100,000 (Direct Cost: ¥2,100,000)
|
Keywords | size classification / particle / twin rollers / dynamic behavior / classification accuracy / adhesion / friction / 分級 / 跳躍運動 / 移動速度 / 高速カメラ |
Research Abstract |
High accuracy size classification is required to improve the performance of functional particles such as solder balls. In this work, a size classifier with twin rollers has been developed to realize high accuracy size classification of spherical particles. Since the two rollers are arranged at a certain inclination with a small opening angle, particles move along the gap between the rollers, and fall down at a point where the width of the gap exceeds the diameter of the particles. To clarify the dynamic behavior of the moving particles along the gap, microscopic observation was carried out, and images recorded with a high-speed digital camera (1/8000 fps) were analyzed. The particle velocity is proportional both to the angular velocity of the rollers and to the tangent of the inclination angle. The particles are not only rolling but also jumping slightly but continuously. The small jumps are caused by the friction between the particle and the rollers, and the forward movement of particles is due to the axial component of the gravitation. The particle velocity can be formulated with the circumferential velocity of the rollers, inclination angle, and friction coefficient. In addition, the particle movement depends on the operational conditions, i.e. directions and rotational velocities of the rollers, but not on the diameter of the particles if they are several hundred micrometers. For smaller particles, the adhesion between a particle and the roller affects the particle movement. The small surface roughness of the rollers lowers the adhesion and 98% of particles were able to be classified even though the particle diameter is 100 μm, and the accuracy of the size classification was within 1 μm.
|
Report
(4 results)
Research Products
(7 results)