Liquid chemical supply system having a plurality of pressure detectors
US7686588B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Oct 17, 2006 |
| Grant date | Mar 30, 2010 |
| Priority date | — |
| Expiry date | Jun 6, 2027 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF04B49/08
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A liquid chemical supply system that performs accurate pressure feedback control and controls the discharge flow rate of liquid chemical with high precision, even when the pressure setting value of the operation pressure differs due to changes in the type of liquid chemical, includes a pump having a pump chamber and an operation chamber separated by a diaphragm comprised of a flexible membrane. The intake and discharge of liquid chemical is performed in accordance with the change in pressure inside the operation chamber. An electro-pneumatic regulator supplies operation gas pressure to the operation chamber. A plurality of pressure sensors having different pressure detection ranges is provided for detecting the operation gas pressure. A controller selectively employs any of the detection results of the plurality of sensors in accordance with the pressure setting value of the operation air that is set for each use, and performs pressure feedback control.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.