Method for detecting and controlling flow rates of the droplet forming stream of an electrostatic particle sorting apparatus
US4325483A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 20, 1979 |
| Grant date | Apr 20, 1982 |
| Priority date | — |
| Expiry date | Aug 20, 1999 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S209/906
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A novel method is disclosed for detecting and controlling the flow rate of a perturbed, droplet-forming stream in an electrostatic particle sorting apparatus. Detection apparatus is located at two points along the stream, at a first particle sensing point for sensing the presence of particles within a core portion of the stream, and at a second downstream point, preferably the stream breakpoint, for sensing light scatter and extinction characteristics which are proportional to the surface characteristics of the sheath portion of the stream. Changes in phase shift, pulse width, duty cycle, pulse area, or breakpoint location are detected by analyzing these sheath surface-related characteristics. An error signal is produced in response to such changes which drives an electromechanical fluid flow regulator to increase or decrease the fluid flow rate in a direction which tends to minimize the error signal. The flow rate is thus maintained at a reference flow rate setting.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.