Device and method for operating a fuel filter

摘要

A device and a method for operating a fuel filter (1) with a diaphragm (16) for cleaning water separated from the fuel, comprising a collecting chamber (9) for the water geodetically arranged at the bottom in a housing (2) of the fuel filter (1), are proposed, comprising at least one sensor (10, 11) each for the maximum (10) and for the minimum (11) water level in the collecting chamber (9), by means of which a valve (13) for discharging the water from the collecting chamber (9) arranged between the collecting chamber (9) and a water purification device (14) containing the diaphragm (16) is controllable. A detection device (21) for detecting the flow behavior of the water between the collecting chamber (9) and the water purification device (14) is present with which at least the time interval (t) of the change of the water level between a signal of the sensor (10) for the maximum and of the sensor (11) for the minimum water level is detectable and in that a computing and memory unit (27) for the evaluation of the signals in the detection device (21) and for signaling (28) a deviation from a predetermined flow behavior of the diaphragm (16) is present.

主权项

1. A method of operating a fuel filter, comprising:
providing said fuel filter including:
a fuel filter housing;a water collection chamber arranged geodetically at a bottom of said housing;a minimum water level sensor arranged on said housing and extending into said water collection chamber to a minimum water level position to detect a minimum water level in said collection chamber and produce a minimum water level signal;a maximum water level sensor arranged on said housing and extending into said water collection chamber to a maximum water level position to detect a maximum water level in said collection chamber and produce a maximum water level signal; providing a water purification device arranged below said fuel filter housing, including:
a water purification device housing having an inlet and an outlet;a diaphragm arranged within said water purification device housing and operable to pass water from said inlet to said outlet while impermeable to flow of fuel; providing discharge valve arranged between said collection chamber and said water purification device and operable to discharge water from said collection chamber into said inlet of said water purification device; providing a detection device configured to detect flow behavior of water flowing between said collection chamber and said water purification device, said detection device in communication with said water level sensors to receive said minimum water level signal from said minimum water level sensor and said maximum water level signal from said maximum water level sensor, said detection device including:
a computing and memory unit configured to evaluate water level signals from said water level sensors and operate said discharge valve;wherein said detection device is controllably connected to said discharge valve to operate said valve to discharge water from said collection chamber;wherein said computing and memory unit is configured to determine a drain time interval (Δt);wherein said computing and memory unit is operable for signaling a deviation from a predetermine flow behavior of water flowing though said water purification device diaphragm during said discharge of water from said collection chamber; andwherein said predetermined flow behavior includes said determined drain time interval; the method comprising the steps of:
providing a predetermined length of time interval of a minimum discharge time (A) below which a defect in the diaphragm is indicated;providing a predetermined length of time interval of a maximum discharge time (C) above which diaphragm replacement is indicated;separating water from fuel and accumulating water in said collection chamber until water level reaches said maximum water level;detecting said maximum water level in said collection chamber by said maximum water level sensor;opening said water discharge valve to discharge water from said collection chamber to said water purification device;draining water from said collection chamber to said water purification device through said discharge valve until high water level is not detected by said maximum water level sensor;closing said water discharge valve;waiting a predetermined delay time, if maximum water level is detected, then
continuing at the step of opening said water discharge valve; waiting a predetermined delay time, if maximum water level is not detected, thenreopening said water discharge valve and determining a drain time interval start time measurement;continuing with the water discharge valve until minimum water level is detected by said minimum water level sensor;determining a drain time interval stop time measurement;closing said water discharge valve;calculating a measured drain time interval (Δt) as elapsed time from the drain time interval start time to the drain time interval stop time;measuring said drain time interval (Δt) as the water drain time between said drain time interval start time to the drain time interval stop time;saving said measured drain time interval (Δt);if said measured drain time interval (Δt)said maximum discharge time (C) then signaling a malfunction of said diaphragm.