Gas supplying apparatus and gas substitution method
US6478040B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 6, 2000 |
| Grant date | Nov 12, 2002 |
| Priority date | — |
| Expiry date | Jul 6, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/87249
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
Gas supplying apparatus and gas substitution method where machinery and parts constituting the gas system are not damaged, and where gas substitution in the gas system is carried out in a short time with good efficiency. The gas substitution, method for substituting a gas after switching into a gas supplying passage by switching the kind of gases to be supplied includes carrying out an operation for fluctuating a pressure in the gas supplying passage within a range of pressure limitation of component parts thereof until a concentration of a gas before switching remaining in the gas supplying passage becomes parts per billion (ppb) level while the gas after switching is made to flow in the gas supplying passage; setting the pressure to a predetermined pressure; and carrying out an operation for increasing a flow rate of the gas after switching in the gas supplying passage under a flow rate limitation of the component parts thereof until the concentration of the gas is before switching remaining in the gas supplying passage becomes sub-ppb level.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.