1. Field of Invention
The invention relates to lighting devices for Christmas and more particularly to a Christmas light string having a socket for electrically connecting to another Christmas light string so that a number of Christmas light strings can be assembled together to form a lighting unit having an increased length.
2. Description of Related Art
There have been numerous suggestions in prior patents for Christmas light string. For example, U.S. Pat. No. 6,344,716 describes a Christmas light string having a plurality of parallel group devices to assure that voltage drop across each five-lamp group is always approximately three volts regardless of the number of bulbs missing, burned out, or whose contacts are degraded.
Further, decorating a Christmas tree with one or more Christmas light strings is well known. Typically, a Christmas light string comprises a plug, an adapter, a plurality of lamps, and a cord connecting them together. In use, the plug is inserted into a wall outlet for electrically connecting to 110 AC volts or 220 AC volts power. The AC power is rectified by the adapter to convert into DC having a voltage of, for example, 24 volts. And in turn, the lamps are powered by 24 DC volts.
However, whether electrically connected in series or parallel, the number of lamps, mounted on a Christmas light string is limited due to the low voltage DC source. And in turn, it limits the length of the Christmas light string. It is often that a person has to prepare a number of Christmas light strings and connect each of them to an independent power source (e.g., a wall outlet or a power strip) in order to increase length if such need arises. However, this not only increases the cost due to, for example, the buying of power strips but also is not practical if there is only one wall outlet available. Thus, the need for improvement still exists.
It is therefore one object of the invention to provide a Christmas light string having a power socket for electrically connecting to another Christmas light string so that a number of Christmas light strings can be assembled together to form a lighting unit having an increased length.
The above and other objects, features and advantages of the invention will become apparent from the following detailed description taken with the accompanying drawings.
Referring to
The Christmas light string 100 further comprises a second cord 40 extending from the plug 10 and being electrically connected to the blades 12 (i.e., the second cord 40 and the first cord 20 being electrically connected in parallel); an adapter 50 disposed in a position of the second cord 40 proximate the plug 10; and a plurality of lamps 60 electrically connected in series or parallel along the second cord 40 and being distal the plug 10.
While the plug 10 has two blades 12 as shown in the preferred embodiment, it is understood that the plug 10 can have three blades 12 in other embodiments without departing from the scope of the invention. Likewise, while the socket 31 has two holes 311 as shown in the preferred embodiment, it is understood that the socket 31 can have three holes 311 in other embodiments without departing from the scope of the invention.
In one configuration of use, the plug 10 is inserted into a wall outlet (not shown) for electrically connecting to 110 AC volts or 220 AC volts power. The AC power is rectified by the adapter 50 to convert into DC having a voltage of, for example, 24 volts. And in turn, the lamps 60 are powered by 24 DC volts.
Referring to
Preferably, light produced by the lamps 60 is substantially the same as that produced by the lamps 60′ because, as stated above, the second cord 40 and the first cord 20 are electrically connected in parallel.
While the invention herein disclosed has been described by means of specific embodiments, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope and spirit of the invention set forth in the claims.
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Number | Date | Country | |
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20080218092 A1 | Sep 2008 | US |