3815747 is referenced by 8 patents and cites 3 patents.

A method and apparatus for softening water in a single conditioning tank system. The water flow through the mineral bed in each service cycle is reversed from the last preceding service cycle and the water-brine solution flow through the mineral bed in each regeneration cycle is reversed from the last preceding regeneration cycle. That is, a downflow service cycle through the mineral bed is followed by an upflow regeneration cycle, an upflow service cycle and a downflow regeneration cycle.

Title
Water softening systems
Application Number
05/257,377
Publication Number
3815747
Application Date
May 26, 1972
Publication Date
June 11, 1974
Inventor
Nygren Charles E
Kay Clifford
Clack Willis E
Agent
Long Theodore J
Winter John M
Assignee
Clack Corporation
IPC
B01d 29/38
C02F 01/42
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