The invention relates generally to landscape illumination and more particularly, to a wiring system for ground mounted lighting fixtures.
The field of landscape illumination generally refers to night time lighting of landscapes for the purposes of enhancement, safety, aesthetics, accessibility, security, recreation, sports, social, and event uses. One common form of landscape illumination is yard and garden lighting. Yard and garden illumination generally refers to light fixtures strategically positioned to provide outdoor illumination of walkways, driveways, steps, private gardens, and other areas. Yard and garden illumination can consist of a long string of light fixtures located adjacent a walkway, for example, so as to provide enough light to see the walkway clearly, yet not be so close to the walkway as to be an obstacle. Light fixtures for yard and garden illumination may also be used to illuminate certain trees, walls, and fences. For the most part, yard and garden lighting fixtures are mounted in soil near the objects to be illuminated.
To secure individual light fixtures that provide yard and garden illumination in a selected position, the fixtures are often mounted in the soil with a spike that extends down far enough in the soil to provide the needed stability for the fixture. Each lighting fixture includes an illumination device, such as one or more light-emitting diodes (LEDs), that must receive electrical energy to function. In today's yard and garden illumination systems, electrical wiring is provided to each of the light fixtures by a single main power cable that is run near each light fixture in a narrow trench in the soil. Each light fixture includes a light source cable to be connected to a power cable. The light fixture cable is long enough to extend out of the light fixture and down into the soil to have its wires clamped or otherwise connected to the main power cable wires located in the trench in the soil. Once electrical connection is made with the main power cable in the soil, the trench is filled in with soil over the power cable, the light fixture cable, and the connections between the two. The connections and the cables are thus buried in the soil. The connections of the light fixture cable to the main power cable in the soil may take different forms. One common technique is to use a connector having connector halves that include sharp prongs. The installer pinches the connector halves together around the main power cable and the sharp prongs inside the connector halves pierce the wires of the main power cable to make electrical contact. The connectors are then pushed down into the trench in the soil approximately three to six inches deep and are covered over with soil. Then the installer moves to the next light fixture in the light string and connects it to the main power cable in the same manner.
The single main power cable is long enough to reach between the low-voltage transformer at the source of electricity and the last light fixture on the string of light fixtures.
There are different direct burial connectors or devices for interconnecting the light fixture wires to the main power wire in a parallel circuit; however, all are for underground use.
Wire connections made under ground are typically exposed to water and possibly fertilizer and other chemicals placed on the yard or garden material. Water and the other chemicals can quickly corrode the wires and the connections causing a loss of power transfer. Various techniques may be used to protect the wires from corroding, such as through the use of heat shrink tubing or other means of water proofing. Underground waterproof connector boxes are also available; however, they increase the cost and make it less convenient to install the light fixtures. This makes the task of connecting the lamps to the main power cable time consuming, expensive, and difficult. These connections can also become unstable because of corrosion.
Another disadvantage of the above method of connecting the individual lamps with the main power cable is that the sharp prongs may miss the wire inside the cable or may sever the wire. In any case, the prongs pierce the insulation over the main power cable which can allow water and chemicals from the soil to attack the copper conductors and the connections with the main power cable. When the main power cable becomes too corroded, the electrical conduction of power will cease thereby requiring excavation of the main power cable and repair. This is a serious shortcoming to the existing methods of interconnecting individual yard or garden light fixtures.
Hence those of skill in the art have recognized a need for an improved wiring system for ground mounted lighting fixtures. A need also exists for a more convenient system and method of the electrical connection process. The present invention fulfills these needs and others.
Briefly and in general terms, the present invention is directed to a wiring system for ground mounted lighting fixtures in which electrical connections are made internally above ground so that the connections avoid degradation by soil chemistry and water from sprinkler.
In particular, there is provided a wiring system for ground mounted lighting fixtures, the lighting fixtures including a light source mounted to a top of a light source support tube, the light source having light source power cable connected to the light source and running through the light source support tube, and a ground mounting spike, the wiring system comprising a base to which the light source support tube is mounted and to which the spike is mounted, the base having a flat base plate configured to rest on the ground surface and to which the spike is attached, the base also having a shell cover mounted to the base plate, the shell cover having a shape selected to form a wiring box within the base between the shell cover and the base plate, wherein an end of the light source power cable is located within the wiring box, whereby the base and wiring box are above ground and a connector device located in the wiring box to receive and interconnect power cable wires, the connector device having a plurality of connector ports, each connector port having a size selected to receive a wire from a power cable, the connector device including an internal electrical circuit that interconnects wires of an incoming power cable with wires of an outgoing power cable and further interconnects a first wire of the light source power cable with a selected wire of the incoming power cable and a second wire of the light source cable with a wire of the outgoing power cable to form a parallel circuit of the light source cable with the incoming and outgoing power cables, the connector device further having releasable mechanical clamps to hold each wire of the power cables in selected fixed positions in their respective ports of the connector device and the connector device electrical circuit, whereby, the connector device forms an integral part of the lighting fixture and locates its electrical circuit and its wire interconnections above ground.
In more detailed aspects, the flat base plate has a diameter selected to provide stabilization to the light fixture to resist tipping. The flat base plate has a threaded center hole and the spike has a threaded upper end whereby the spike and flat base plate are assembled in fixed relationship by mating the upper threaded end of the spike with the threaded hole of the flat base plate. The flat base plate has an opening that receives the incoming power cable from underground into the wiring box for connection to the connector device. The flat base plate has an opening that receives the outgoing power cable from underground into the wiring box for connection to the connector device.
In further aspects, the flat base plate has a first opening that receives the incoming power cable from underground into the wire box for connection to the connector device, and the flat base plate has a second opening that receives the outgoing power cable from underground into the wire box for connection to the connector device. The shell cover has a size selected to receive the flat base plate within it to surround the base plate thereby providing protection of the base plate and the connector device from rain and sprinkler water. The releasable mechanical clamps of the connector device include levers that, when moved in one direction, apply a clamping force to hold the respective wire in a fixed position in the port of the connector device, and when the lever is moved in a different direction, release the clamping force from the respective port thereby allowing easier mounting of a wire into the port and removal of a wire from the respective port.
In yet further aspects, the releasable mechanical clamps of the connector device include clamp springs that are controlled by the levers to force and secure wires into electrical contact with the circuit of the connector device and wherein the levers release the clamp springs to permit removal or mounting of the wires in the port. The shell cover includes a base light source lamp mounting tube on which the light source support tube is mounted. The light source support tube is slid over the base light source lamp mounting tube and a set screw is mounted through the light source support tube into contact with the base light source lamp mounting tube to mouth both together in a fixed position whereby water runs off the light source support tube onto the shell cover thereby resisting water entering the wiring box.
In a different aspect, the light source support tube is slid over the base light source lamp mounting tube and the light source support tube has an inner diameter and the base light source lamp mounting tube has an outer diameter, wherein the inner diameter and outer diameters are selected to result in a press fit between the mounting of the light source support tube onto the base light source lamp mounting tube to mount both together in a fixed position whereby water runs off the light source support tube onto the shell cover thereby resisting water entering the wiring box.
In particular method aspects of the invention, there is provided a method of wiring ground mounted lighting fixtures, the lighting fixtures including a light source mounted to a top of a light source support tube, the light source having light source power cable connected to the light source and running through the light source support tube, and a ground mounting spike, the method comprising assembling a base, comprising mounting a flat base plate configured to rest on the ground surface to a shell cover, the shell cover having a shape selected to form a wiring box between the shell cover and the base plate, wherein an end of the light source power cable is located within the wiring box, and attaching the spike to the flat base plate, mounting the base to the light source support tube whereby the base and wiring box are above ground, mounting a connector device in the wiring box, receiving and interconnecting power cable wires in a plurality of connector ports in the connector device, each connector port having a size selected to receive a wire from a power cable, the connector device including an internal electrical circuit that interconnects wires of an incoming power cable with wires of an outgoing power cable and further interconnects a first wire of the light source power cable with a selected wire of the incoming power cable and a second wire of the light source cable with a wire of the outgoing power cable to form a parallel circuit of the light source cable with the incoming and outgoing power cables, clamping the wires in the connector ports with releasable mechanical clamps to hold each wire of the power cables in selected fixed positions in respective ports of the connector device and in selected positions in the connector device electrical circuit, whereby, the connector device forms an integral part of the lighting fixture and locates its electrical circuit and its wire interconnections above ground.
In further method aspects, the step of assembling a base with a flat base plate further comprises assembling the base with a flat base plate that has a diameter selected to provide stabilization to the light fixture to resist tipping. The step of assembling a base with a flat base plate further comprises assembling the base with a flat base plate that has an opening receiving the incoming power cable from underground into the wiring box for connection to the connector device.
Yet further method aspects are directed to the step of clamping the wires in the connector ports with releasable mechanical clamps comprising controlling the clamping with levers that, when moved in one direction, apply a clamping force to hold the respective wire in a fixed position in the port of the connector device, and when the lever is moved in a different direction, releasing the clamping force from the respective port thereby allowing easier mounting of a wire into the port and removal of a wire from the respective port. The method of wiring ground mounted lighting fixtures of claim 19 wherein the step of clamping the wires in the connector ports with releasable mechanical clamps comprises clamping the wires using clamp springs that are controlled by the levers to force and secure wires into electrical contact with the circuit of the connector device and wherein the levers release the clamp springs and clamping force to permit easier mounting of the wires in the ports and removal of the wires from the ports.
The features and advantages of the invention will be more readily understood from the following detailed description that should be read in conjunction with the drawings.
Referring now in more detail to the exemplary drawings in which like reference numerals designate corresponding or like elements among the several views,
As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. The figures are not necessarily to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention.
Referring now to
A light source component 90 of the light fixture 70 comprises a light source tube 92 and a light source head 94. In this embodiment, the light source head includes a light source in which light emitting diodes (not shown) are used although other embodiments may use different sources of light. Electrical energy to power the light source in the lamp head is conducted through the hollow lamp tube by a lamp cable in this embodiment. Part of a lamp cable 96 that is used to power the light source is shown in
The lamp component 90 of
In another embodiment, the lamp mounting tube may have a taper (not shown) such that the smaller diameter part of the lamp mounting tube caused by the taper has a diameter that fits into the lamp tube 90. However, the larger diameter part of the taper will interfere with the hollow portion of the lamp tube and create a press fit thereby locking the lamp tube and lamp connector tube firmly together. Such mechanical connections of two tubes are well known to those of skill in the art and no further details are provided here. It is important that whatever connection is used resists the flow of water into the base.
Turning now to
Different types of cable material may be used to run electrical power to the series of light fixtures of
The connector device 80 shown in
Also located on the base plate 74 are two threaded holes 88 on either side of the connector device 90. These holes are used for assembly of the base plate with the shell cover 72 to form the base 76 (see
Only two levers are labeled with numeral 172 but all are meant to be labeled with that same reference numeral. Numeral 172 is not used in
Also shown in
Therefore, the wiring system for ground mounted lighting fixtures 180 has provided the ability to more easily, rapidly, and accurately wire each light fixture with the power cable by providing electrical connections above ground that are mechanically held in place securely inside the light fixture. The connections are easily made and released through the use of spring levers individually used for each wire of each cable. Because they are located above ground, the electrical and mechanical connections are protected from sprinklers and chemicals in the soil. If a light fixture fails and replacement is necessary, the wiring system in accordance with the invention allows for quick and easy replacement due to the wiring connections being located in the base 76 of the fixture. Such light fixture replacement may be required due to various reasons, one of which is physical damage to the fixture caused by a lawn mower, for example.
Unless the context requires otherwise, throughout the specification above and claims that follow, the word “comprise” and variations thereof, such as, “comprises” and “comprising” are to be construed in the normal patent law sense; i.e., an open, inclusive sense, which is as “including, but not limited to.”
As required, a detailed embodiment of the present invention is disclosed herein; however, it is to be understood that the disclosed embodiment is merely exemplary of the invention that may be embodied in various and alternative forms. The figures are not necessarily to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention.
While the present invention has been described herein in terms of a certain preferred embodiment, those skilled in the art will recognize that modifications and improvements may be made without departing from the scope of the invention.
The exemplary embodiment described above is not intended to represent all possible forms of the invention. Rather, the words used in the specification are words of description of an embodiment, not limitations on the invention itself, and it is understood that various changes may be made to the embodiment without departing from the scope of the invention.