Method and appatatus for pulverizing material
US5114083A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 12, 1990 |
| Grant date | May 19, 1992 |
| Priority date | — |
| Expiry date | Feb 12, 2010 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB02C2017/165
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
The present invention relates to a method and apparatus for pulverizing a material to produce a fine powdery material such as silica powder as a material for a filler for sealing semiconductors. It has a shell and a screw shaft mounted in the shell. A disk having an inverted conical bottom surface is coaxially secured to the bottom of the screw shaft. The disk serves to protect the blade of the screw shaft from wear. Also owing to the inverted conical bottom surface, a centripetal force acts on the screw shaft while in rotation, thus preventing it from running out of true. By providing a plurality of screw shafts in the shell, the fluid in the shell flows in a complicated manner, thus increasing the pulverizing efficiency. A partitioning plate formed with a hole in the upper or lower part thereof may be provided between the adjacent screw shafts to minimize the possibility of shortcircuiting of the material from the inlet of the shell to its outlet. The respective screw shafts may have different revolving speeds, different heights or different screw pitches from one another to create a complicated fluid flow in the shell and thus to improve the pulverizing efficiency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.