Alarm warning to add regenerative salt to water softener etc. - uses switch held open by submerged float carrying gradually dissolving salt

摘要

Automatic electro-mechanical warning system is described in which a dose of soluble additive has been dissolved. In partic the system can warn that it is time to recharge with salt the regenerative salt soln tank of an ion exchange water softener of the type fitted to domestic washing machines. The system comprises a soln tank contg a switch actuating lever pivoted on a fixed, horizontal axis. The lever is fitted with a salt carrier pan of lower density than the soln. A dose of salt holds the pan down so that the lever retracts the magnet of proximity switch. As salt is dissolved, the pan rises, the switch is actuated to close contacts and the visual and/or audible alarm issues its warning.