Fuel filter with filter recognition

US9072992B2 · kind B2 · utility

Assignee

• FIRMA HENGST GMBH & CO. KG · DE

Inventors

• Frank Mendel · Tonawanda, US
• Norbert Prinz · Greven, DE

Key dates

• Filing date: Jun 25, 2008
• Grant date: Jul 7, 2015
• Expiry date: Oct 8, 2031

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B01D2201/4046
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

A modification of a fuel filter for use with an internal combustion engine is described. The modification provides a switch element that, in conjunction with the water level sensor conventionally provided in the filter, enables detection of the presence or absence of a filter insert or whether an improper insert has been installed in the filter housing. When the filter insert is inserted or removed, the switch element makes or breaks an electrical circuit that is part of the water level sensor. The control unit is thus able to detect switch states of three different variables in the filter: the water level is/is not too high; the filter insert is/is not installed; or the correct filter is/is not installed. The control unit accordingly allows or prevents operation of the motor, depending on the detected switch state.