Filter condition indicator having moveable sensor and aggregate flow counter

A method for monitoring fluid flow through a fluid treatment filter placed in a fluid flow path leading to a faucet by use of circuitry and comprising the steps of:

• a) positioning a fluid flow responsive, movable sensor in the fluid flow path adapted to move in response to fluid flow in the fluid flow path;
• b) monitoring a position of the moveable sensor as a user opens and closes the faucet and providing a two-state signal output based on the position of a moveable member in the fluid flow path, one state of the two state signal output indicating that the fluid flow in the fluid flow path exceeds a threshold rate;
• c) initializing a timer when the filter is installed in the flow path;
• d) energizing said timer whenever said one state of the two state signal output is present;
• said timer providing a timer output related to an aggregate time of fluid flow through the filter of at least the threshold rate since installation of said filter;
• e) comparing the timer output with a predetermined value corresponding to a predetermined amount of filter use;
• and
• f) when the timer output reaches the predetermined value, activating an indicator to indicate that a predetermined amount of filter use has occurred.

Apparatus for providing an indication of a condition of a filter used in treating water dispensed from a faucet comprising:

• a) means comprising an on/off switch or providing a flow signal when water is flowing through a conduit leading to an outlet;
• b) a flow timer electrically coupled to the on/off switch and responsive to said flow signal, said timer being operative to measure an interval of time that the on/off switch is providing said flow signal including means for accumulating said intervals, said timer being further operative to provide a timer output when a total of the accumulated intervals reaches a predetermined time period;
• c) said timer comprising a clock for providing regularly occurring clock pulses, a counter for counting the regularly occurring clock pulses, and selector means for adjustably determining a proportion of clock pulses which are counted by the counter;
• and
• d) an indicator having a control input coupled to the flow timer to provide an indication in response to a timer output based upon the time period of water flow through the filter.

A method for monitoring a condition of a filter for treating water dispensed by a faucet by use of circuitry and comprising the steps of:

• a) monitoring water flow in a water flow path leading to a faucet by positioning a fluid flow responsive, movable member in the water flow path and providing an output when the water flow reaches a threshold flow sufficient to move the movable member to a flow indicating position;
• b) initializing a timer circuit each time a filter is installed;
• c) activating said timer circuit in response to the output indicating water is flowing to the faucet;
• said timer circuit providing a timer output related to aggregate time of water flow equaling or exceeding the threshold flow since initialization of the timer circuit;
• d) using the timer circuit for comparing the aggregate time with a predetermined time duration corresponding to a useful filter life;
• and
• e) when the aggregate time indicated by the time circuit output reaches the predetermined time duration, activating an indicator to provide an indication that the filter should be replaced.

Apparatus for providing an indication of the condition of a filter that treats a fluid comprising:

• a) a conduit that defines a portion of a fluid flow path leading to or from a filter;
• b) a fluid flow responsive, moveable member positioned within the conduit adapted to move to a flow indicating position when fluid flow through the conduit equals or exceeds a threshold flow rate;
• c) a flow sensor having a switch that changes state in response to movement of the moveable member to the flow indicating position to produce a flow indicating output signal;
• d) circuitry electrically coupled to the switch and including a timer responsive to the flow indicating output signal for timing periods of fluid flow through the conduit;
• said timer including means for accumulating the timing periods and output means for providing an indicator output signal when the accumulated fluid flow time periods exceed a predetermined time period;
• and
• e) an indicator having a control input electrically coupled to the indicator output signal to provide an indication of filter condition.