Vacuum filter for swimming pools

DETAILED DESCRIPTION Having regard to the foregoing disclosure, the following is claimed as the inventive and patentable embodiments thereof: 1.
A vacuum filter-swimming pool combination for vacuum flow filtration through a filter bed of water from a swimming pool, the swimming pool comprising a perimeter gutter and a water recirculation system having line connections from the pool and from the gutter to the vacuum filter and from the vacuum filter back to the pool, the vacuum filter comprising a tank open to atmospheric pressure; a dividing wall across the tank, separating the tank into first and second compartments; a filter bed of particulate material in the second compartment; first and second fluid flow connections communicating the two compartments, the first adjacent an upper portion and the second adjacent a lower portion of the filter bed; third and fourth fluid flow connections communicating the second compartment with the water recirculation system for the swimming pool, the third adjacent an upper portion and the fourth adjacent a lower portion of the filter bed; an inlet line communicating the swimming pool with the first compartment; a direct inlet line connection communicating the perimeter gutter of the swimming pool with the second compartment; and valves controlling flow between the compartments via the fluid flow connections, between the first compartment and the inlet line, and between the second compartment and the water recirculation system; the swimming pool being at a level equal to or above the level of the first and second compartments of the vacuum filter, for gravity flow of water therebetween, whereby the level of water in the swimming pool maintains a corresponding level of water in the first compartment, thereby providing a head of water for backwash flow upwardly through the filter bed; the water level in the filter compartment being maintained by the pressure head in the swimming pool at a first normal level, and flow from the gutter into the filter compartment increasing the water level in the filter compartment above the first normal water level with a resultant throttling effect on flow from the swimming pool into the compartment in proportion to increased gutter flow, and reserving a sufficient capacity in the water recirculation system to accommodate increased gutter flow, and prevent flooding of the gutter