Patent ID: 6850850

Claim:
A system for metering the volume of flow of a fluid through a filter, to enable the level of filter usage, to be indicated, wherein a preset level of metered fluid flow volume indicates a corresponding level of filter usage, and wherein, in the system, a source of the fluid is adapted to be connectable to the filter, to enable the fluid to flow through the filter and through the system, and wherein the system is adapted to self-generate current for the system responsive to the flow of the fluid therethrough, comprising: a flow volume processing element, for processing the volume of the flow of the fluid over time to determine the level of filter usage; a current-inducing element, for inducing current responsive to the flow of the fluid; a current-generating element, for generating current including electrical charge responsive to the current induced therein by the interaction thereof with the current-inducing element, so as to self-generate current responsive to the fluid flow and the interaction of the current-inducing element therewith; a storing element, for storing the electrical charge generated by the interaction of the current-inducing element and the current-generating element so as to charge the storing element, adapted to generate current from the electrical charge stored therein for activating the flow volume processing element; and a discharging element, for enabling the current in the flow volume processing clement to discharge therethrough; wherein, upon each interaction of the current-inducing element and the current-generating element, the metering system sequences through a metering cycle whereby the storing element charges, the current generated in the storing element activates the flow volume processing element such that the flow volume processing element starts up, operates, and calculates and stores the volume of fluid flow, and the current from the flow volume processing element discharges through the discharging element such that the flow volume processing element shuts down.