Patent · US Expired

Method and apparatus for removal of by-products of chemical vapor deposition from oil for vacuum pump

US4228004A · kind A · utility

7Cited by
1References
32Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 12, 1979
Grant dateOct 14, 1980
Priority date
Expiry dateApr 12, 1999

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB01D37/04
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

For a vacuum pump, as used to maintain a partial vacuum in a diffusion furnace for chemical vapor deposition in intermittent runs wherein oil for the vacuum pump becomes contaminated by particulates, an apparatus for removal of particulates from oil for the vacuum pump comprises a settling tank, which is connected to receive oil from the vacuum pump, an oil pump, which is arranged to pump oil from the settling tank, means for filtering particulates from oil pumped from the settling tank, a plurality of oil valves, which are arranged to control flow of oil from the vacuum pump, through the settling tank, through the filtering means, and into the vacuum pump, means for operating the oil pump and opening the oil valves for timed intervals wherein oil flows from the vacuum pump, through the settling tank, through the filtering means, and to the vacuum pump, and means for coordinating the intervals with the runs so that each interval is initiated approximately when a run is terminated.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.