Method for pneumatically controlling discharge of particulate material
US5599581A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 21, 1994 |
| Grant date | Feb 4, 1997 |
| Priority date | — |
| Expiry date | Sep 21, 2014 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB65G53/50
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A method for dispensing or depositing particulate material includes accumulating particulate material in a nozzle having an opening at the bottom for discharging the particulate material, and applying positive air pressure to a buffer chamber positioned in communication with the accumulation of particulate material to start and control the flow of particulate material through the opening and applying negative pressure to the buffer chamber to stop the flow of particulate material. An unobstructed interface can exist between a surface of the particulate material and air in the buffer chamber. In one embodiment, roofing shingle granules are applied intermittently to a moving coated asphaltic sheet through a slot to form strip roofing shingles.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.