Patent · US Expired

Fool-proof plug in fluid system

US6668851B2 · kind B2 · utility

0Cited by
17References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 3, 2002
Grant dateDec 30, 2003
Priority date
Expiry dateJul 9, 2022

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T137/598
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

A plug for plugging a first port and blocking insertion of a second plug into a second port of a fluid system. The plug includes a threaded plug portion and a blocking stem portion extending from the threaded plug portion. The stem portion projects into the second port and blocks insertion or mounting of a second plug and thereby keeps the second port unplugged. In a disclosed embodiment, the plug is mounted into the return port of an oil pump unit of an oil burner to block bypassed flow from returning to the local reservoir of the oil pump unit. This prevents two plugs from being inadvertently mounted that could otherwise block all bypass flow in the pump unit and cause excess pressure build ups and blown seals.

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