| US 7,412,896 B2 | ||
| Filter change indicator | ||
| Leon P. Janik, Suffield, Conn. (US); Stephen J. Vardion, Glastonbury, Conn. (US); and Michael J. Williams, Glastonbury, Conn. (US) | ||
| Assigned to Stanadyne Corporation, Windsor, Conn. (US) | ||
| Filed on Nov. 17, 2006, as Appl. No. 11/601,307. | ||
| Application 11/601307 is a continuation in part of application No. 10/930970, filed on Aug. 31, 2004, granted, now 7,137,303. | ||
| Prior Publication US 2007/0125179 A1, Jun. 07, 2007 | ||
| This patent is subject to a terminal disclaimer. | ||
| Int. Cl. H01L 21/00 (2006.01) | ||
| U.S. Cl. 73—753 [257/302; 73/723] | 20 Claims |
| 1. A fluid system pressure indicator comprising:
a housing comprising a containment vessel having an interior and a fluid communication passage providing a first fluid path
between a portion of the containment vessel interior and an exterior of the containment vessel;
a pressure communicator located within the housing, said pressure communicator having a fluid contact portion and an electrical
circuit actuator;
an electrical contact associated with said actuator;
a fluid diaphragm sealingly engaged with the housing and the pressure communicator such that the fluid contact portion of
the pressure communicator is fluidly separated from the actuator;
a pressure communicator spring that exerts a continuous unidirectional pressure on the pressure communicator;
an electrical indicator having a first circuit terminal and a second circuit terminal, said first and second circuit terminals
being selectively connected electrically by said electrical contact associated with the electrical circuit actuator.
|