1. Field of the Invention
This invention relates to fluid dispensing systems which automatically dispense fluid to animals only during predetermined periods of time.
2. Description of the Prior Art
Experiments and controlled feeding often require maintaining animals on a fluid restriction regimen. These restrictions may require limiting the amount of fluid an animal may consume, the time period during which the animal may consume the fluid, or some combination of both of these restrictions. Controlled feeding programs in which a fluid is available to an animal at the same time every day present scheduling difficulties. Typically, glass bottles containing fluid are manually placed in the animal's cage each time access to the fluid is required. This manual procedure often produces cumbersome work schedules for experimentors and laboratory personnel, particularly when the experiments last several weeks or months, including weekends and holidays.
U.S. Pat. No. 3,294,066 describes an animal feeding system wherein a time actuated valve causes a predetermined amount of water to enter a feeding unit where it will mix with a dry food material and the weight of such mixture will downwardly displace the feeding unit so as to expose a feeding nipple portion, thus allowing the animal to feed from the unit. This system, unlike the present invention, lacks a provision for draining or retrieving any fluid remaining when an animal feeding interval is over and it requires that a disposable feeding bag be replaced after each use. Additionally, this system differs from the present invention in that it is designed to dispense a fixed amount of fluid and is not adaptable to experiments where the watering time interval, rather than the quantity of fluid to be consumed, is to be restricted.
U.S. Pat. No. 3,720,185 discloses an automatic animal feeding system in which a level sensing device controls the amount of liquid delivered to a chamber where it is mixed with a solid food material and then dispensed at individual feeding points. This system utilizes automatic valves to dispense the food but is designed to provide a predetermined amount of food to an animal rather than to allow the animal access for a limited period of time.