The present invention relates generally to ultrasonic humidifiers, and, more particularly, to ultrasonic humidifiers of the type having a plurality of removable water tanks for holding the water which is used to produce a mist.
During the winter season when temperatures decline below 32 degrees F. the humidity level in homes and offices generally drop below 25 per cent. This low humidity condition can cause a seasonal occuring affliction called rhinitis sicca, more commonly known as dry nose and/or throat. This affliction can be easily overcome by increasing the moisture level in the home or office.
In the past, steam vaporizers were utilized to add moisture to the surrounding air. However, in recent years, the steam vaporizer has been replaced with the humidifier.
One well known type of humidifier relies upon a moving belt/fan mechanism to turn water into a cool mist. Another type of known humidifier utilizes a heating element to generate a warm mist. Still another type of known humidifier uses a small electronic component called a transducer which is capable of transforming electrical energy into mechanical energy for generating a cool mist. More specifically, the transducer includes a vibrating part called a nebulizer which vibrates quietly at greater than 11/2 million times per second in order to convert water into a fine, cool mist. Humidifiers using a nebulizer for generating a cool mist are more commonly referred to as ultrasonic humidifiers and are the latest advance in the humidifier field.
Ultrasonic humidifiers usually incorporate therein a removable water tank or container for holding a supply of water. The tank contains a vale which controls the flow of water from the tank into a reservoir at the bottom of the humidifier. The nebulizer for churning the water into a fine, cool mist is usually located at the bottom of the reservoir. When the water tank is fully or partly empty it is simply lifted out, taken to a source of water such as a water faucet, refilled and then returned for subsequent use. An example of such a humidifier is the Model No. HM-310 Ultrasonic Humidifiers manufactured by Holmes Products Corporation of Holliston, MA.
In some ultrasonic humidifiers the water capacity is increased by providing a pair of water tanks as opposed to a single water tank. The water is unloaded from the tanks simultaneously with both tanks starting to empty their water supply at the same time and becoming completely empty at the same time. Refilling one tank before the other will have no effect on the emptying of water from the other tank. An example of a two tank ultrasonic humidifier is the Model No. HM-1500 Ultrasonic Humidifier manufactured by Holmes Products Corporation of Holliston, MA. The main advantage of having two water tanks rather than one is that the individual tanks are smaller and easier to handle than one large tank. As can be appreciated, however, the overall advantages of two tanks as opposed to one tank have not been maximized.