Automatic Filter

Compared to modern wall mounting filters or even complete filtering and cooling water systems, the old ceramic filters seem at first an option doomed to obsolescence. This consideration, however, is not true if we consider the numerous models manufactured today (from the most traditional filter like Sao Joao to the many others with "modern design") as well as the number of adherents of the same.

I am one of those fans and I believe that among the many advantages presented by the manufacturers of these filters, the ones mentioned below are indisputable:

- Filtering by gravity retaining more particles than the forced filtering (when water passes through the candle when it will be consumed).

- The time water remains at rest provides an additional opportunity for the elimination of chlorine and odors.

- The water temperature is pleasant (fresh) at no cost to its cooling.

This project is proposed to automate these water filters and thus eliminate one of its disadvantages, compared to filtering systems that are directly connected to tap: The manual supply.

Since a system with buoys would not have sufficient strength to withstand the pressure of water coming from a tap, a solenoid valve of the type used in laundry machines is adopted as a basis for design.

(click on the pictures to enlarge)

The actuation of this solenoid valve takes place via a micro switch. This is a simple approach that avoids the use of electronics to monitor the water level. Because of that, the power consumption happens only when the solenoid valve is turned on.

A plastic lever was included only to increase the distance between minimum and maximum levels and thus increase the duration of on and off cycles. The option was for greater intervals with greater duration of replenishing water.

See also details of the limits of the buoys responsible for the activation of the micro switch (obtained from a Sindal) and a swab tube used to guide the steel rod into the filter. The water level always remains at the upper limit with the water column varying in 2cm in height.

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