US5236578A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Filter life indicator for water purification system using magnetically actuated switch
Assignee: American Home Water Products Corp
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Filing: 1992-07-07
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Granted: 1993-08-17
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Expires: 2012-07-07
Abstract
Abstract A filter life indicator is described herein utilizing a constant flow channel and a flow actuated switch incorporating a reciprocating magnetic member to start a timer. Circuitry monitors this timer and actuates a visual or audible indicator when the filter needs to be replaced. The timer consists of a pulse generator, a scaling circuit, a counter, and a comparator. During flow pulses are counted and compared to a preset limit. And to accommodate filters having differing life expectancy, modules corresponding to each filter are installed to change the scaling circuit.
Inventors
- 👤 Brett J. Oleskow
- 👤 Evan P. Browne
- 👤 James D. Meyer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 23:36
CPC Classifications
B; B01; B01D; B01D61/00; B01D61/02; B01D61/08; B01D61/081; B01D61/12; G; G01; G01F; G01F1/00; G01F1/05; G01F1/20; G01F1/22; G01F1/24; G01P; G01P13/00; G01P13/0006; G01P13/0013; G01P13/002; C; C02; C02F; C02F2209/00; C02F2209/44; C02F2209/445
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
182 words
In a water filtering system connected to a water line having means to selectively control the flow of water through a defined channel of flow, the improvement comprising: switch means actuated by said flow for detecting said flow, said switch means comprising a magnetic member restrained in the channel of flow for reciprocal motion responsive to said flow and a magnetically operated switch positioned proximate said magnetic member for actuation thereby, wherein said magnetic member is constrained for reciprocal motion within said channel of flow; and circuit means coupled to said switch means for timing the duration of said water flow and providing an indicator signal when a predetermined amount of flow has occurred, said circuit means including pulse generation means, counter means coupled to said pulse generation means for accumulating the count of generated pulses in response to activation by said switch, and comparator means for comparing said count against a predetermined maximum count, wherein said counter means includes "divide by N" circuitry and a separably replaceable module means for selecting the "N" factor and for selectively scaling said generated pulses.
Claim 2
Dependent Claim
182 words
In a water filtering system connected to a water line having means to selectively control the flow of water through a defined channel of flow, the improvement comprising: switch means actuated by said flow for detecting said flow, said switch means comprising a magnetic member restrained in the channel of flow for reciprocal motion responsive to said flow and a magnetically operated switch positioned proximate said magnetic member for actuation thereby, wherein said magnetic member is constrained for reciprocal motion within said channel of flow; and circuit means coupled to said switch means for timing the duration of said water flow and providing an indicator signal when a predetermined amount of flow has occurred, said circuit means including pulse generation means, counter means coupled to said pulse generation means for accumulating the count of generated pulses in response to activation by said switch, and comparator means for comparing said count against a predetermined maximum count, wherein said counter means includes "divide by N" circuitry and a separably replaceable module means for selecting the "N" factor and for selectively scaling said generated pulses.
Claim 3
Dependent Claim
16 words
The water filtering system of claim 1 wherein said replaceable module means comprises predetermined jumper connections.
Claim 4
Dependent Claim
166 words
In a water filtering system connected to a water line having means to selectively control the flow of water through a defined channel of flow, the improvement comprising: switch means actuated by said flow for detecting said flow, said switch means comprising a magnetic member restrained in the channel of flow for reciprocal motion responsive to said flow and a magnetically operated switch positioned proximate said magnetic member for actuation thereby, wherein said magnetic member is constrained between a constriction in said channel of flow and a fixed repelling magnet positioned within said channel of flow; and circuit means coupled to said switch means for timing the duration of said water flow and providing an indicator signal when a predetermined amount of flow has occurred, said circuit means including pulse generation means, counter means coupled to said pulse generation means for accumulating the count of generated pulses in response to activation by said switch, and comparator means for comparing said count against a predetermined maximum count.
Claim 5
Dependent Claim
166 words
In a water filtering system connected to a water line having means to selectively control the flow of water through a defined channel of flow, the improvement comprising: switch means actuated by said flow for detecting said flow, said switch means comprising a magnetic member restrained in the channel of flow for reciprocal motion responsive to said flow and a magnetically operated switch positioned proximate said magnetic member for actuation thereby, wherein said magnetic member is constrained between a constriction in said channel of flow and a fixed repelling magnet positioned within said channel of flow; and circuit means coupled to said switch means for timing the duration of said water flow and providing an indicator signal when a predetermined amount of flow has occurred, said circuit means including pulse generation means, counter means coupled to said pulse generation means for accumulating the count of generated pulses in response to activation by said switch, and comparator means for comparing said count against a predetermined maximum count.
Claim 6
Dependent Claim
31 words
The water filtering system of claim 3 wherein said counter means includes "divide by N" circuitry and a replaceable module for selecting the "N" factor, for selectively scaling said generated pulses.
References Cited (Backward Citations)
US4522077A
Cited
US4623451A
Cited
US4808994A
Cited
US4918426A
Cited
GB2219662A
Cited
WO1991000986A1
Cited
JPH03107716A
Cited
US5089144A
Cited
US5089144B1
Cited
US5055641A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-08-16 | 1997-02-15 | 1997-08-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-08-16 | 2001-02-15 | 2001-08-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-08-16 | 2005-02-15 | 2005-08-17 | $7700.00 | Window Closed / Lapsed |