Patent · US Expired

Test apparatus employing pneumatic bridge for testing pneumatic flow resistance and related methods

US5347847A · kind A · utility

5Cited by
5References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 18, 1992
Grant dateSep 20, 1994
Priority date
Expiry dateDec 18, 2012

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01B13/00
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

In an apparatus for testing pneumatic flow resistance of a test component, such as an air filter useful in a system for admixing parenteral solutions, a pneumatic bridge has two branches connected, via a filter, a flow restrictor, and a flowmeter, to a source of gas under regulated pressure. Each branch comprises two arms with a centerpoint. The bridge has a pressure transducer connected between the centerpoints and arranged to detect pressure imbalances in the bridge. Each arm comprises a flow restrictor, namely a needle valve, which is calibrated via a vernier head. The valves are adjustable to balance the bridge. In one arm, in which the needle valve can be fully opened, the test component is connectible to constitute a flow restrictor. The transducer produces an output displayed via a digital voltmeter, which may be calibrated.

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