Patent · US Expired

Multi-stage EDM filter

US6881330B2 · kind B2 · utility

4Cited by
11References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 19, 2002
Grant dateApr 19, 2005
Priority date
Expiry dateJul 22, 2022

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB01D29/58
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A two-stage, retrofit filter is adapted for use with an electrical discharge machine (EDM) includes nested inner and outer filtering elements that may be placed as a unit in the same tank and over the apertured standpipe used for a one-stage filter, such that the fluid to be filtered now flows through each of the multiple filter elements. The retrofit EDM filter may be configured for flow in either direction, though the usual arrangement is one whereby the fluid being filtered flows up through the bottom of the tank, out the apertured standpipe, and into the inner filter element. Preferably, the filter elements are cylindrical, pleated elements composed of a technical grade filter paper. In the preferred embodiment, a pressure-operated release valve is provided in conjunction with the inner filter, such that when a predetermined pressure is reached due to the entrapment of contaminants by the inner filter, the valve opens to allow the fluid to be filtered to flow through the outer filter.

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