Patent Application
20060102540
1. Field of the Invention
This invention relates broadly to water filtration. More particularly, this invention relates to a skimmer having a replaceable cartridge filter.
2. State of the Art
Conventional skimmers for pools and spas include a weir which is hinged at the bottom and provided with a float at the top. Behind the weir is a sump in which a filter or a basket is placed. A filter pump is coupled to the sump and draws water from the pool or spa over the weir and into the sump through the filter or basket. The floating weir assures that the pool/spa water is drawn from the surface into the sump. This causes floating waste to be drawn across the surface of the water and into the skimmer.
In skimmers which have baskets rather than filter cartridges, the owner can see waste accumulate in the basket and will know to empty the basket periodically. Skimmers which utilize replaceable filter cartridges are different. A good example of such a skimmer is shown in U.S. Pat. No. 4,637,873 issued Jan. 20, 1987 to DeSousa et al. A cylindrical filter cartridge is disposed vertically in the skimmer housing below the weir. It is difficult or impossible to determine visually whether the filter needs to be replaced. In addition, because of the way the filter cartridge is disposed in the skimmer housing, it is possible that the outer surface will become unevenly coated with waste, thereby requiring replacement more frequently than if the filter were evenly coated.
It is therefore an object of the invention to provide a skimmer and filter for a pool or spa.
It is another object of the invention to provide a skimmer which uses replaceable filter cartridges.
It is a further object of the invention to provide a skimmer which provides a visual indication of when a filter cartridge needs to be replaced.
It is also an object of the invention to provide a skimmer which makes more efficient use of filter cartridges.
In accord with these objects, which will be discussed in detail below, the skimmer according to the invention includes a housing, a skimmer face plate coupled to the housing, and a flexible weir gate coupled to the face plate. When the filter pump is activated, the weir gate flexes to allow water to flow both over the top of the face plate and in a vertical column between the face plate and the housing. The interior of the housing has a curved wall so that when a column of water passes the weir gate and is pulled down into the housing, a whirlpool effect is realized. A vertical filter cartridge is mounted on a rotational bearing in the housing so that it can spin about its axis. The inlet of a filter pump is coupled to the cartridge via the bearing. The inlet of the pump is also coupled to a below the surface water inlet via a check valve. When the filter is clean, water is drawn through it by the pump and the filter spins about its axis due to the whirlpool effect of the column of water. When the filter reaches a threshold dirt covering, water is no longer drawn through it and the draw through the housing is decreased, causing the check valve to open to allow more water to the pump. As the flow rate through the housing decreases, the rate of rotation of the cartridge decreases, thus giving a visual indication that it needs to be replaced. Spinning the cartridge during operation also causes it to be more evenly coated with dirt. This makes more efficient use of the cartridge.
According to an illustrated embodiment, the weir gate flexes about a central mount and two filter cartridges are arranged side by side. When clean, the filter cartridges spin in opposite directions.
Additional objects and advantages of the invention will become apparent to those skilled in the art upon reference to the detailed description taken in conjunction with the provided figures.
Referring now to
As seen best in
The inlet of a filter pump 30 is coupled to the cartridge 24 via the bearing 28 as shown in
There have been described and illustrated herein several embodiments of a pool/spa skimmer. While particular embodiments of the invention have been described, it is not intended that the invention be limited thereto, as it is intended that the invention be as broad in scope as the art will allow and that the specification be read likewise. Thus, while the illustrated skimmer has two filter cartridges, it will be appreciated that a skimmer with a single cartridge could be constructed incorporating the features of the invention. In a single filter embodiment, the face plate would be configured to allow only a single column of water to enter the housing. Instead of a flexible weir gate, a spring biased hinged gate could be used. It will therefore be appreciated by those skilled in the art that yet other modifications could be made to the provided invention without deviating from its spirit and scope as claimed.
