This invention relates to lighting assemblies. More specifically the present invention relates to circuitry for a DC run agricultural light that changes colors through dimming.
The farming industry has greatly evolved over the past several decades, going from primarily outdoor based family farms to indoor corporate run facilities. For example, poultry are now often housed in cage systems where the chickens move from one place in the system to the next, staying off the ground where they can be harmed. In this manner the facilities house numerous poultry indoors without access to the outside.
As a result, artificial lighting is a main source of lighting for the farm animal, whether incandescent, LED, high pressure sodium, compact fluorescent or the like. As scientists have studied animals, such as chickens, turkeys, swine, cows and the like under artificial light the scientists have come to understand not only how animals see light as compared to humans, but also the effects that characteristics of light have on different animals. Many tests have been conducted related to the effects of lighting on animals such as chickens, turkeys, swine, cows and the like.
In particular, scientists have recognized that photoperiod or the modulation of light to animals is important. Swine studies exist showing that swine raised under continuous darkness for 24 hours were less active than swine raised under a modulated twelve hours of dark and twelve hours of light. Meanwhile swine under 24 hours of light were most active, but also showed increased levels of stress and thus the pigs welfare was considered to be affected by the presence of continuous darkness or light.
Similarly, another characteristic of light shown to effect animals is the irradiance or intensity of light. For example, tests in swine show that piglets raised under 2-6 or even 10 lux do not gain as much weight as compared to 70-100 lux light whereas 2500 lux light showed weight loss. Meanwhile in another test on piglets 50 lux light gave improved health and improved immune status as compared to 10, 20, 40 and 120 lux light. So again, intensity of light is another light characteristic known to effect animals and swine.
A final factor that effects animals, is the spectrum or color of light. Tests on poultry show that the use of different wavelengths of light, such as red or blue wavelengths can result in heavier bodyweight, increased daily gain, decreased mortality, increased egg production and the like.
In addition, a need in the art exists for energy efficient lighting within agricultural facilities. In particular agricultural facilities can contain 50, 100 or more lights depending on the size of the facility. Typically these facilities contain 100 Watt incandescent light bulbs that are a drain on energy and cause power bills to be tremendous. In addition, because of the environment there is an abundance of feces, ammonium, mud, food pieces and the like within the barn. Thus, typically the 100 Watt bulbs must be within a casing or jelly jar of some type to try to protect the lighting from the elements. In addition wash downs expose the lighting to water, again requiring protection for the lighting to prevent breakage, shortage or worse fire conditions.
As a result of this research, agricultural lighting manufacturers have begun manufacturing lighting that present different spectrum of light, such as red or blue to enhance production of the animals. For example U.S. Ser. No. 13/050,910 entitled, Light Sources Adapted to Spectral Sensitivity of Diurnal Avians and Humans to Grajcar that is incorporated in full herein is directed toward light emitting diode (LED) lighting assemblies that can be dimmed in order to provide different wavelengths of light. Thus an assembly can start off red and be dimmed to appear blue or vice versa to accommodate the animal. Similarly, U.S. Ser. No. 13/357,330 entitled, Differential Illumination to Select Egg Laying Sites to Grajcar that is also incorporated in full herein provides for an aviary system for egg laying with similar concepts.
Still problems remain. In particular, the circuitry presented in these applications are directed toward an AC power sources where on occasion a DC based power source is presented as an input. Additionally, occasionally AC power sources can cause flickering and other unintended consequences. Therefore a need in the art exists for an agricultural light that is able to provide growth enhancements through color shifting, yet operates on a DC power supply.
Therefore a principle object of the present invention is to provide a DC circuit that provides color shifting properties.
Another object of the present invention is to provide a robust, cost effective agricultural lighting assembly.
These and other objects, advantages and features will become apparent from the rest of the specification.