Water softening control
Abstract
Abstract In a water-treating apparatus comprising in combination cationexchange means for removing divalent cations from water to be treated and substituting for the divalent cations, cations selected from the group consisting of hydrogen ions and sodium ions, anion-exchange means for removing divalent anions from the water and substituting for the anions, anions selected from the group consisting of hydroxyl ions and chloride ions, sensing means consisting of a contractile fiber having a length dependent on the concentration of calcium ions in the water and located in the apparatus in the flow stream of the water at a point downstream of at least a portion of the cation-exchange means, the sensing means being sensitive to the concentration of calcium ions in the water, means for regenerating the cation-exchange means and the anion-exchange means, and means responsive to the sensing means for activating the regenerating means in response to a predetermined level of calcium ion concentration in the water, the improvement in the water-treating apparatus comprising as the sensing means a water insoluble contractile fiber composed of polymers containing nonhydrolyzable groups which groups are selected from the group consisting of carboxy, primary, secondary and tertiary amines and imine.
Inventors
- 👤 Jonas Weiss
- 👤 William Hodes
Bibliographic Details
Claims Analysis
Total Claims: 3References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-05-10 | 1974-11-09 | 1975-05-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-10 | 1978-11-09 | 1979-05-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-10 | 1982-11-09 | 1983-05-11 | $7700.00 | Window Closed / Lapsed |