06186140 is referenced by 65 patents and cites 41 patents.

The present invention provides for a filter assembly (

124

) which includes a filter element (

128

) and a memory device (

402

). The memory device (

402

) allows for a record of the filter element's usage to be available at all times even if the filter assembly (

124

) is moved from one filtering system to another one. In another embodiment of the invention, the filter assembly (

124

) interacts with a filtering device such as air unit (

130

) which periodically updates the memory device (

402

) while the air unit (

130

) is operational. The air unit (

130

) also periodically checks to see if the filter assembly (

124

) has reached the end of its useful life. If so, the air unit provides an audible and/or visual alarm.

Title
Respiratory filter element having a storage device for keeping track of filter usage and a system for use therewith
Application Number
8/818797
Publication Number
6186140 (B1)
Application Date
March 14, 1997
Publication Date
February 13, 2001
Inventor
Michael Paul Hoague
New Market
MD, US
Agent
Karl G Hanson
US
Pedro P Hernandez
US
Assignee
3M Innovative Properties Company
MN, US
IPC
A61M 16/00
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