Abstract:
The in-ground, or “well light”, fixture comprises a hollow cylindrical housing with an angled end and an flat end, a lamp assembly easily mounted at either end, and a baffle. The lamp assembly is rotatably and vertically adjustable within the housing and either the angled end or the flat end may be placed upward by virtue of a pair of channels extending down the length of the housing. Fasteners are provided on the lamp assembly for attaching one or more filters above the lamp face and to create a protective air gap that prevents debris from accumulating on the lamp.

Description:
FIELD OF THE INVENTION 
   The present invention relates to lighting fixtures for landscape and environmental lighting applications and, more particularly, to in-, or below-ground lighting fixtures. 
   BACKGROUND OF THE INVENTION 
   The use of outdoor lighting fixtures has become increasingly popular for illuminating buildings, gardens, pathways, and entrance ways as the nighttime play of light on the landscape and exterior structures is aesthetically pleasing. Additionally, such lighting provides enhanced security by reducing eliminating dark hiding places and unobserved entry points for intruders. The most widely used outdoor lighting systems include one or more low voltage lighting fixtures that are connected to a 12 V transformer that is, in turn, connected to a standard 120 VAC line. Each lighting fixture generally includes a housing, a lamp assembly having a halogen lamp or conventional bulb and a reflector, and a lens or window. Many configurations are known for providing a variety of different lighting effects. 
   Landscape lighting fixtures, most of which are mounted at or above ground level can be considered to appear somewhat incongruous with the surrounding vegetation during daylight hours, when the illumination function is not in use. Further, because of the constant exposure to the elements, above ground lighting fixtures are generally required to be made of expensive, high quality materials, such as non-corrosive metal alloys, in order to provide durability and a reasonable resistance to damage so as not to appear cheap and unkempt. 
   As an alternative to the above-ground placement of landscape lighting fixtures, recessed, in-ground lighting fixtures, also known as “well lights”, have gained widespread acceptance. In certain applications, the use of below-ground landscape lighting is preferable over above-ground varieties, especially in areas surrounding walkways where an above-ground element could poses a tripping hazard or in lawn areas where the use of a lawn mower presents a risk of damage to the fixture. One such in-ground lighting fixture is described in U.S. Pat. No. 6,491,407 of Beadle, which is incorporated herein by reference. 
   A problem experienced with below-ground light fixtures is the limited ability to control the direction of illumination efficiently and easily due to the limited range of illumination and convenient access to the lamp. It would be an advantage to have an apparatus in which the lamp is easily accessible to the user for adjustment of beam quality and direction of the fixture. 
   Some existing lighting fixtures are designed to be placed in the ground with their faces parallel with the ground. Others fixtures have their upper edge cut at an angle, so that the exit window is at shallow angle relative to the ground, with one side of the fixture extending slightly above the ground. The fixture is selected according to the position of the exit face—there is no variability once the fixture is selected, short of digging the hole in the ground at a different, non-vertical angle, which tends to be imprecise. 
   Most well lights have a grating over the exit face, which protects the lamp from impact while permitting air to enter the housing. A significant problem with many well lights is the fire hazard that is created when dried plant debris builds up on the lens of the hot lamp. Occasionally, the gratings are removed because they are either broken or the block too much light to achieve the desired effect. This increases the risk of fire because more and larger plant debris can build up on the hot lamp. 
   The need remains for an in-ground lighting fixture that provides variability in the position of the lamp to provide better control and more efficient use of the light beam, and that greatly reduces the fire hazard caused by build-up on the hot lamp. The present invention is directed to such a fixture. 
   SUMMARY OF THE INVENTION 
   It is an advantage of the present invention to provide a single in-ground lighting fixture that can be placed in the ground to emit a beam that is either directed upward, perpendicular to the ground surface, or angled. 
   It is a further advantage of the present invention to provide an in-ground lighting fixture that allows multi-axis adjustment of the beam. 
   Still another advantage of the present invention is to provide one or more protective lenses that prevent build up of debris on the lamp face to reduce fire hazards commonly associated with well lights. 
   In an exemplary embodiment, the in-ground, or “well light”, fixture comprises a hollow cylindrical housing with a first, flat end and a second, angled end. Either the flat end or the angled end can be used as the upper end depending on the preference of the user and the purpose for which the lighting fixture will be used. 
   In the preferred embodiment, the lamp assembly includes a pair of pivots that extend from diametrically opposite sides of the assembly, where each pivot has a circumferential edge that is configured to slide within a channel running along the length of the housing. The combination of the pivot edges and their corresponding channels allows the lamp assembly to be positioned near either end of the housing depending on whether the fixture is to be installed with the angled or flat end up. The same combination of the pivots and the channels forms a gimble for varying the angle of the lamp assembly within the housing. The use of the flat end or angled end of the housing and the adjustability of vertical position and the angle of the lamp assembly provide the maximum flexibility with a single fixture. 
   The lamp assembly comprises an enclosure with a base and an upper ring that retains the lamp within the assembly. The upper ring has threads on its inner sidewall that mate with threads on the outer surface of the upper edge of the base to enclose the edges of the lamp. The lamp is preferably a sealed beam PAR lamp, but may be a combination of a halogen lamp, a parabolic reflector and a window or lens disposed over the lamp and held in place by the upper ring to enclose and protect the lamp against contaminants. The lamp assembly is preferably watertight. A socket is located within the base for providing electrical connection between the lamp and wires that are fed through the wall of the base. 
   O-rings or similar resilient materials disposed on the pivot heads retain the lamp assembly at the desired height and angle within the housing by providing resistance against movement within the channels. 
   A baffle is attached at the upper end of the housing to protect the lamp assembly against physical contact, to permit airflow within the housing and to reduce glare from the lamp. The baffle may be held in place by an interference fit or by forming threaded bores in the housing the light deflector snaps onto ether end of the housing. The baffle may alternately be attached to the housing end by screws. 
   The housing may be formed from polyvinylchloride (PVC), plastic or other durable, corrosion-resistant polymer. The baffle may be formed from brass, anodized or powder-coated aluminum, high impact plastic or any other material that provides appropriate durability and weather-resistance as well as being aesthetically pleasing. The lamp housing is preferably formed from high temperature plastic. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will be more clearly understood from the following detailed description of the preferred embodiments of the invention and from the attached drawings, in which: 
       FIG. 1  is an exploded perspective view of the in-ground lighting fixture. 
       FIG. 2  is perspective view of the fixture with the housing partially cut away. 
       FIG. 3   a  is a front elevation of the fixture with the fixture with the angled edge up;  FIG. 3   b  is a cross sectional view taken along line A-A of  FIG. 3   a.    
       FIGS. 4   a - 4   d  are perspective views of the in-ground lighting fixture with the angled edge up showing the lamp assembly at two different heights and a perpendicular light direction ( FIGS. 4   a  and  4   b ) and two different heights with an angled light direction ( FIGS. 4   c  and  4   d ). 
       FIGS. 5   a - 5   d  are perspective views of the in-ground lighting fixture with the flat edge up showing the lamp assembly at two different heights and a perpendicular light direction ( FIGS. 5   a  and  5   b ) and two different heights with a angled light direction ( FIGS. 5   c  and  5   d ). 
       FIG. 6   a  is a diagrammatic side view showing the interaction between a pivot and a channel according to the present invention, and  FIG. 6   b . is a cross-sectional view of the pivot and channel taken along line  6   b - 6   b  of  FIG. 6   a.    
       FIG. 7 . is an exploded perspective view of the protective lens assembly of one embodiment of the invention. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   As illustrated in  FIGS. 1-5 , the in-ground lighting fixture  10  includes a cylindrical housing  100 , a lamp assembly  200 , and a light deflector or cover  300 . 
   The cylindrical housing  100  has a first, flat end  102 , a second, angled end  120 , an outer diameter, and an inner diameter. Housing  100  may be formed from polyvinylchloride (PVC), polymer, plastic or similar materials that are resistant to corrosion and oxidation. In the preferred embodiment, housing  100  is injection molded from a thermoplastic polyester resin such a Valox®. Two channels  130  extend vertically (longitudinally) at diametrically opposite locations of the inner surface of the housing. Each channel  130  is formed from a pair of rails with arced or shallow C-shaped depressions on their inner faces to define a channel spacing  162 , as seen in  FIG. 6   b , which generally corresponds to the outer diameter of O-ring  220 . The channels  130  are preferably formed integrally with the housing, for example, during a injection molding process. Additional ribs  160  may also be formed to enhance the structural strength of the housing  100 , either extending the entire length of the housing, or for a portion of the length, for example, as illustrated in  FIG. 2 . It is important to retain the circular cross-section of the housing to ensure uniformity of the space between the channels. When the housing is formed by injection molding, a relatively thin, inwardly extending annular ring  170  is formed at the lengthwise (vertical) center of the housing to help retain circular rigidity as the material cools. The channels  130  and optional ring  170 , if not injection molded, may be made of plastic or metal and may be added later and attached to the inside diameter of the housing  100  with a commercially available adhesive, or attached by screws, or by any other suitable means. 
   Cover  300  is circular in shape with an area of sufficient size to fit over and cover the upper edge of the housing  100  to enclose the housing. Because the area to be covered when the angled end is up is larger, if a single baffle is to be provided to cover either end, the baffle diameter will be slightly larger than the diameter of the housing. Cover  300  may be flat, but preferably has a convex surface, with a waffle pattern of alternating openings and ridges that transmit light emitted from the fixture that is generally perpendicular to the beam direction while blocking scattered light to reduce glare. Tabs  310  extend downward from the outer edge of cover  300  to align with openings  140  or  150  near the angled and flat ends, respectively, for attachment of cover  300  to housing  100 . Tabs  310  may have openings through which a screw or pin may be passed to mate with openings  140  or  150 , as appropriate, or a bump  312  may be formed on the inner surface of the tab so that the bump snaps into  140  or holes  150  when they are aligned. Cover  300  may be formed from a high-impact, injection molded plastic or thermoplastic polyester resin such as Valox®, but may also be made of a metal such as brass, anodized or powder-coated aluminum, or other suitable material. The lower edge of cover  300  has an annular ring with an outer diameter that fits closely within the inner diameter of housing  100 . 
   The lamp assembly  200  comprises a retaining ring  210 , a lamp housing  240 , and a lamp  230 . The lamp  230  is commercially available and has conductors for attachment of wires connected to a voltage source, a generally parabolic reflector, and an emitting portion. In the preferred embodiment, the lamp is a sealed PAR (parabolic aluminized reflector) lamp, typically a PAR-36 lamp, with a halogen tube or incandescent filament. Alternatively, an open reflector type lamp, such as a MR-16 halogen lamp, may be used by positioning a lens to enclose and seal the reflector. The base of lamp  230  is retained within lamp housing  240 , which at its upper edge has an external thread to mate with an internal thread in the inner surface of retaining ring  210 . 
   Lamp housing  240  is generally bowl shaped and encloses a connector (not shown) to which the lamp conductor is connected. A flange  242  formed just below the threaded upper edge abuts the lower edge of retaining ring  210  when two parts are assembled. Optional ribs  244  are formed in a ring around the outer surface of the lamp housing to facilitate grasping the lamp assembly when the assembly needs to be opened to replace the lamp or for repair. In the preferred embodiment, the lamp housing  240  is formed from high temperature plastic, polymer or thermoplastic polyester resin, preferably formed by injection molding. 
   Lamp housing  240  includes conductors or a pass-through opening for conductors, e.g., wire, (not shown) for providing electrical contact between the socket and a voltage source. It may be desirable to fill the lower portion of the housing  240  with a potting material to surround and seal the socket to prevent moisture intrusion. The lamp housing provides a significant advantage of currently commercially-available well lights, in which the contacts on the back of the lamp are typically exposed. Because the upper surface of the fixture is not sealed, water from rainfall or from irrigation builds up within the housing. When the water level in the housing gets high enough to reach the contacts, it will create a short circuit that interferes with proper operation of the lamp. The sealed lamp housing  240  protects the lamp contacts from water the collects in the fixture housing. 
   Retaining ring  210  has an inner diameter forming a lip to hold the lamp  230  in place while being sufficiently open to avoid blocking the light from the lamp  230 . Two circular pivots  215  extend from the outer edge of ring  210  at diametrically opposite locations to define a rotational axis for gimbled operation. Each pivot  215  has a channel formed around its circumferential edge for receiving an O-ring  220 . The material of which the O-ring is formed should be resilient and sufficiently soft to generate friction when in contact with the surfaces of the C-shaped depressions of channel  130 . The diameter and thickness of O-ring  220  are selected to closely fit the arc of channel  130  so that the pivot  215  will slide vertically and pivot within channel  130  with resistance. The resistance should be sufficient to hold the lamp assembly in position unless force is intentionally applied by someone who may be installing or adjusting the fixture. 
   In the preferred embodiment, the retaining ring  210  is formed from high temperature plastic, preferably by injection molding. Alternatively, the retaining ring  210  may be made of other injection molded plastics or polymers or formed from metal such as brass, copper, stainless steel or coated metal, or any other suitable materials that are resistant to corrosion and oxidation. 
   In the preferred embodiment, the pivots  215  are formed integrally with the retaining ring  210 . Alternatively, the pivots may be separate pieces that are screwed into or otherwise attached to the ring. In an alternate embodiment, the pivots  215  may be attached to and extending from the outer surface of base  240  as opposed to ring  210 . Optional bosses or pegs  232 , or other appropriate fasteners may be attached to the outer surface of retaining ring  210  to retain one or more filters (not shown) over the lamp  230 . The filter(s) will have notches configured to mate with the bosses to hold the filter in place. The filter (not shown) is preferably formed from a high temperature plastic such as Lexan® and may be colored or textured to achieve a desired lighting affect. 
     FIGS. 3   b  and  7  illustrate a preferred arrangement for providing filters over the lamp face. Retaining ring  210  has multiple bosses  270  extending upward to support one or more filters. Each boss has a bore for receiving a fastener  330 , which may be a screw or peg. As illustrated, filter  324  is a diffuser lens formed from Lexan® or other high temperature plastic. Openings are made near the perimeter of the lens at the same radial spacing as bosses  270 , so that a fastener  330  can be inserted through each opening and into the bore in boss  270 . In the preferred embodiment, the bore in boss  270  is threaded and fastener  330  is a screw. Filter  324  is preferably textured, which can be seen clearly in  FIG. 3   b , with small prisms that refract the light from the lamp to spread the beam. This is advantageous because PAR lamps tend to project narrow beams, while the desired lighting affect for landscape purposes is usually a diffuse, spreading beam. Filter  322  sits on top of filter  322  and is typically a color filter, the color of which can be selected to enhance the color of the object being illuminated. For example, where plants are being lit, a blue filter will be used to remove the orange tones that are common in PAR lamps and which tend to make green plants look unhealthy. Filter  322  also has openings to match the radial spacing of the bosses so that fastener  330  serves to hold both filters in place. Preferably, the two filters have matching curvatures so that they fit closely together. Additional filters may added to the stack for additional lighting affects. 
   The heights of the bosses  270  are selected to act as spacers that define a spacing  326  (shown in  FIG. 3   b ) between the face of lamp  230  and the lower surface of lens  324 . Spacing  326  provides an air gap to permit air flow around the lamp while the lamp is protected against debris build-up. With the protective lens assembly over the lamp, even if the cover  300  were to be damaged or removed, a hot lamp would not create a fire hazard because it would not come in contact with debris. 
     FIGS. 4   a - d  and  5   a - d  illustrate the two orientation options for the housing,  FIGS. 4   a - d  show the housing oriented with the angled end  120  up and the flat end  102  down, while  FIGS. 5   a - d  show the opposite installation.  FIGS. 4   a  and  5   a  show the lamp assembly  200  situated to project light straight upward with the assembly set back from the upper edge of the fixture, so that the light is more diffuse.  FIGS. 4   b  and  5   b  show the lamp assembly again aimed straight upward, but the assembly is closer to the upper edge of the fixture, so that the light is more focused.  FIGS. 4   c  and  5   c  illustrate the lamp assembly  200  at an angled orientation relative to the ground surface, i.e., not perpendicular to the center axis of the housing, with the assembly  200  set back from the upper edge to achieve a more diffuse light beam.  FIGS. 4   d  and  5   d  show the lamp assembly angled and positioned closer to the upper edge to project a more focused beam at an angle relative to the housing axis. 
   When the in-ground lighting fixture is ready to be placed into a hole in the ground, the user selects the configuration he or she desires depending on the lighting application. The user removes the cover  300  from the housing  100  to provide access to the lamp assembly  200 . Assuming that the pivots  215  of the lamp assembly  200  are already retained within the channels  130  near the flat end  102 , if the user wishes to place the angled end up, he or she slides the pivots  215  toward the flat end and completely out of the channels. The housing is then flipped over and the pivots inserted into the channels from the angled end  120  and slid to the desired height and angle within the housing. Similarly, if the lamp assembly  200  is always positioned within the angled end  120 , the assembly is pulled upward to release the pivots  215  from the channels  130 . The housing is flipped over and the pivots  215  are then inserted into the channels from the flat end. 
   For installation, the housing  100  is placed in the desired orientation (flat end or angled end up) into a hole in the ground into which appropriate conductive cable has been run. The cable ends are pulled up so that there is sufficient slack in the cable to permit manipulation for connection to the lamp assembly  200 . The conductors (not shown) that extend from the base of lamp assembly  200  are connected to the cable conductors using appropriate connectors. The pivots  215  are then inserted into their corresponding channels and slid to the desired height within the housing. The lamp assembly is rotated around the pivots to attain the desired angle, after which the cover  300  is attached to the upper edge. 
   It should be noted that while the housing will usually be cylindrical for ease of manufacture and installation, the shape of the baffle is not so limited, and different geometric shapes, e.g., square, pentagonal, hexagonal, etc., may be utilized to achieve a particular aesthetic effect. 
   The in-ground lighting fixture of the present invention offers wide directional variability with the entire fixture designed and adapted for in-ground use. The configuration of the present invention is aesthetically pleasing and is constructed with a focus on simplicity of use, ease of adjustment, and durability of construction. 
   Other embodiments and modifications of the present invention may occur to those of ordinary skill in the art in view of the se teachings. Accordingly, the invention is to be limited only by the following claims which include all other such embodiments and modifications when viewed in conjunction with the above specifications and accompanying drawings.