Patent Application
20080198596
None.
None.
None.
High intensity discharge lamps (HID) lamps are widely used in various structures having high ceilings such as gymnasiums, warehouses, commercial buildings and the like. HID lamps typically utilize metal halide, mercury vapor, high or low pressure sodium depending on the application and lighting characteristics desired. These lamps may range from 500 to 1,000 Watts for example, so that the buildings wherein such HID lamps are utilized are well lit. However, one problem with such HID lamps is the significant energy consumption occurring in these lamps.
In order to maximize downward lighting, bell-shaped reflectors are typically utilized to fit over the base of the HID lamps. The lamps are screwed into a power supply in order to power the lamp. The reflectors are typically made of polished aluminum or similarly reflective lightweight material. The opposite lower end of the reflector may be opened or may be covered with a translucent lens to further diffuse lighting emanating from the lamp and provide a substantially attractive appearance.
As an alternative to HID lamps, some commercial applications utilize fluorescent light fixtures, which often have fluorescent tubes with a length of four or eight feet. These tubes are often placed parallel to the floor or substrate to produce a predetermined lumination pattern. Installation and replacement of these types of tubes, particularly eight foot tubes, is often difficult due to the length of the tubes and the electrical connectors being located at distal ends of the tube.
Compact fluorescent lamps have a generally “folded-over” bi-axial design which attached to a light fixture at a single end. Alternatively, such lamps may be helical or corkscrew in nature. Sales of compact fluorescent lamps (CFLs) have increased in volume due to improvements in the performance and reduction of prices in this type of lamp. In addition, the market for CFLs has been spurred on by the integration of lamp and electronic ballast with either a screw-in or bayonet fitting allowing easy replacement of consumable lamp.
The CFLs are produced in various shades of white including “warm white” or “soft white” providing a light very similar to an incandescent bulb; “white”, “bright white” or “medium white” producing a yellowish white light, whiter than an incandescent lamp but still on the warm side; “cool white” emitting more of a pure white tone; and “day light” having a slightly bluish white appearance. Compact fluorescent lamps have two main parts. First, the CFLs utilizes a gas filled tube. Second, the CFLs typically utilize magnetic or electronic ballast. The ballast may be remote from the tube or may be connected to the tube. Electrical energy in the form of an electrical current passes from the ballast through the gas causing it to emit ultraviolet light. The ultraviolet light excites a white phosphorus coating on the inside of the tube emitting a visible light.
Prior art low-bay luminaires utilize compact fluorescent lamps generally in a base up orientation and tilted inside the reflector to extend downwardly from the base. There are several problems with prior art luminaires of this type. First, in the prior art, base-up configurations, the lamp sockets are closely spaced near the top of the reflector creating excessive heat. Accordingly, various prior art luminaires are only rated for 25 degrees Celsius ambient operating temperature. Second, there is always a desire to increase the total lumen output, the sum of light output from nadir to 180° of the luminaire. There is also a desire to increase the total efficiency of the luminaire, which is measured as a percentage of the lamp output by the luminaire. There is also a desire to decrease the amount of uplight emitted from the luminaires since such uplight is only useful with very high reflectant ceilings. Further, there is a desire to decrease the amount of lighting in the glare zone which is defined as the 60 to 90 degree area. There is also a desire to increase the light in the useful zone defined as the 0 to 60 degree area.
Given the foregoing, it will be appreciated that a luminaire optical system is needed which provides lower operating temperature and therefore increased life, high total output and efficiency, increased useful light and decreased glare.
A low-bay luminaire comprises a reflector having a first smaller opening at an upper end and a second larger opening at a lower end, a ballast housing disposed above the smaller opening, a stem extending from near the ballast housing downward and radially outward, a socket disposed near a radially outward end of the stem, a compact fluorescent lamp having a base for electrical connection at a single end, the compact fluorescent lamp configured in a base down diagonal orientation wherein the lamp extends from the base upwardly toward the lamp center. The low-bay luminaire further comprises a reflector plate disposed within the reflector. The stems are connected to the reflector plate. The low-bay luminaire further comprises a ballast within the ballast housing. The low-bay luminaire further comprises wiring between the ballast and the socket. The reflector is bell-shaped. The low-bay luminaire further comprising a wire-grid extending across said second lower opening. The low-bay luminaire further comprises a lens disposed over the second larger opening at the lower end. The lens is connected to the reflector along a lower edge of the reflector and an upper edge of the lens. The lens is integrally formed with the reflector. The low-bay luminaire further comprises a wire-grid extending over the lens. The lamp extends diagonally upward and radially inward. The lamp is rotated at an angle from a radially extending axis.
A luminaire comprises an upper enclosure portion, a reflector connected to the upper enclosure portion, a stem extending radially outwardly and downwardly within the reflector, a socket connected to the stem, a lamp assembly connected to the socket, the assembly having a base and a lamp, the base positioned radially outwardly and downwardly so that the lamp extends upwardly and radially inwardly from the base. The luminaire the reflector being acrylic. The reflector being polished aluminum. The lamp is angled at a range of about 20 to 30 degrees from a horizontal plane. The lamp having electrical connection at a single end.
A luminaire optical system comprises a ballast housing, a reflector having an upper end and a lower end, the ballast housing connected to the reflector, a plurality of lamp assemblies each having a base and a lamp portion, the lamp in electrical communication with the base at a single end, the base disposed downward and radially outward of the lamp. The luminaire optical system further comprises a stem extending downward and radially outward to a lowermost end of the lamp assembly. The luminaire optical system further comprises a socket positioned at a lower end of the stem. The lamp assembly is connected to the socket. The lamp assemblies being rotated from radially extending reference axes.
A luminaire optical system comprises a reflector having a plurality of lamp assemblies arranged therein, a lamp assemblies spaced apart circumferentially, the lamp assemblies having a base and a lamp extending from the base, a socket in electrical communication with each of the lamp assemblies, the map assembly having a base down arrangement such that the lamp extends upwardly and inwardly within the lamp. The luminaire optical system further comprises a ballast housing connected to the reflector. The luminaire optical system further comprises a reflector plate within the reflector and a plurality of stems depending from the reflector plate. The sockets receive the lamp assemblies. The stems extend downwardly and radially outward. The luminaire optical system further comprises a ballast plate disposed within the ballast housing. The lamp assemblies having a single electrical connection at one end of the assembly. The lamp assemblies extending upwardly toward the reflector plate.
A luminaire optical system comprises a ballast housing connected to a reflector, a reflector plate positioned in an upper portion of the reflector, a plurality of stems extending downward and radially outward from the reflector plate, a plurality of lamp assemblies having a single electrical connection, the lamp assemblies connected to a lower end of the stems and extending upwardly an radially inward toward the reflector plate. The ballast housing having at least one upper vent aperture and at least one lower vent aperture. The lamp assemblies being circumferentially spaced apart.
The above-mentioned and other features and advantages of this Luminaire Optical System, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the system taken in conjunction with the accompanying drawings, wherein:
It is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless limited otherwise, the terms “connected,” “coupled,” and “mounted,” and variations thereof herein are used broadly and encompass direct and indirect connections, couplings, and mountings. In addition, the terms “connected” and “coupled” and variations thereof are not restricted to physical or mechanical connections or couplings. The term reflector as used herein is meant to include both reflective surfaces, refractive surfaces, or a combination of the two, which both reflect and refract light. The term useful light zone means light in the range of 0-60 degrees from nadir and is measured in Lumens. The term glare zone means light in the range of 60-90 degrees from nadir and is measured in Lumens. The term uplight means light in the range of 90-180 degrees from nadir and is measured in Lumens. The term total efficiency represents a percentage of the total lamp output produced from the uplight, glare and useful light output.
Referring now in detail to the drawings, wherein like numerals indicate like elements throughout the several views, there are shown in
Referring initially to
Referring still to
Referring now to
Within the interior of the ballast housing 12 are a plurality of ballasts 28. The electronic lamp ballasts 28 use electronic circuitry to provide proper starting and operating electrical condition to power one or more fluorescent lamps 56. Specifically, the ballasts 28 control the current moving through a lamp 56 and each of the ballasts 28 may control one or more lamps 56. Electronic ballasts typically change the frequency of the power from the standard mains frequency to 20,000 Hertz or higher in order to eliminate flicker associated with fluorescent lighting. As a result, fluorescent lamps operate at a higher efficiency. Because of the high frequency of operation, the electronic ballasts are generally smaller, lighter and more efficient and therefore run cooler than line frequency magnetic ballasts. In addition, the vents 18, 20 allow removal of heat from ballasts 28 from the ballast housing 12. The present luminaire optical system 10 may be used with either electronic or magnetic ballasts.
As previously indicated, the ballasts 28 may control one or more lamps. The ballasts 28 may also have a dimming function by opening circuits to selected lamps, thereby illuminating only selected lamps to provide the dimming function. Alternatively, the ballasts 28 may be dimming ballasts which provides dimming function to each lamp.
Also located within the interior portion of the ballast housing 12 and extending from the ballast plate 24 is at least one strap 22. The strap 22 is substantially U-shaped extending upwardly from opposed sides of the ballast plate 24 and centrally located within near the upper portion of the ballast housing 12. The strap 22 generally provides structural support for the ballast housing 12 and connects the ballast housing 12 to the ballast plate 24. The strap 22 may be other shapes providing structural rigidity may be utilized.
A threaded rod 27 extends upwardly through the central portion of the upper housing portion 16 and through strap 22. A nut or washer assembly 26 captures the housing 12 on the rod 27 and against the reflector 30.
Depending from the ballast plate 24 is a plurality of fasteners or bolts 34 which are connected to a reflector plate 36. Specifically, the embodiment depicts that the fasteners 34 depend from the ballast plate 36, through the reflector top 32 and through the reflector plate 36. Each of the fasteners 34 has a nut located adjacent a lower end thereof. The nuts retain the reflector plate 36 on the fasteners 34 depending from the ballast plate 24. However, other means may be utilized for suspending the reflector plate 36 within the reflector 30 such as brazing, welding or riveting the plate 36 to posts depending from the ballast plate 24. The reflector plate 36 is defined by a pre-selected diameter and is made of a reflective material such as polished aluminum or other reflective material. In addition, lower ends of the clips 33 (
Depending from the reflector plate 36 are a plurality of equidistantly spaced stems or arms 40. The stems 40 are fastened to the reflector plate 36 and extend diagonally downwardly and radially outward from the plate 36. The stems or arms 40 may be integrally formed with the plate 36 or alternatively may be fastened or otherwise connected to the reflector plate 36 by various means other than the fasteners indicated. The stems 40 may be formed of various materials which may or may not be reflective. Each of the stems 40 are generally U-shaped in cross-section with a first side portion 42, a spine 43 and an opposite side portion 44 which provide rigidity to the stem 40 and inhibit bending due to the heat and weight of the lamp 56. Alternative stem shapes may be utilized in order to support an array of lamp assemblies 52 therefrom.
At an end of each of the stems 40, opposite the reflector plate 36, is a socket 50. The socket 50 is connected to the end or finger 46 of the stem 40. The socket 50 is generally cylindrical in shape but may be various alternative shapes which receive a lamp assembly 52 described further herein. The socket 50 may receive a threaded base portion or the socket 50 may receive a push-type bayonet attachment in order to provide electrical communication between the lamp assemblies 52 and the ballasts 28. The lamp assemblies 52 of the present luminaire system 10 have a single electrical connection at one end, for a single connection to socket 50. The stems 40 are generally arranged in a circular pattern so that the lamp assemblies 52 are also generally circular in configuration.
Referring now to
Fluorescent lamps are more efficient than incandescent bulbs of an equivalent brightness because more of the consumed energy is converted to useable light and less is converted to heat, allowing fluorescent lamps to run cooler. For example, an incandescent lamp may only convert ten percent (10%) of its power input to visible light whereas a fluorescent lamp producing the same amount of useful visible light energy may only require one-third to one-quarter as much electricity input. Further, typically a fluorescent lamp will last between ten and twenty times as long as the equivalent incandescent lamp.
In the embodiment depicted the lamps 56 are compact fluorescent lamps. For example, 8 lamps consuming 42 Watts (8-42 Watts) each may be utilized wherein each lamp has an output of about 3,200 Lumens. In another example, there may be 4-57 Watts lamps utilized in the luminaire 10 wherein each lamp 56 has an output of 4,300 Lumens. In yet another example, there may be 4-70 Watts lamps utilized wherein each lamp 56 has an output of 5,200 Lumens. Greater wattages may be utilized such as 60 Watts, 70 Watts, or 85 Watts lamps. It is also within the scope of this invention that a three lamp arrangement be utilized wherein the each lamp is, by way of example, 120 Watts with an output of about 9,000 Lumens.
Wiring (not shown) from the ballast 28 extends through the ballast plate 24, through the reflector top 32 and through the reflector top 36. Once the wiring is through the reflector top 36, the wiring may extend along the inside of each stem 40 to the socket 50. Due to the channel shape of the stems 40, each stem acts as a wiring tray or conduit and hides the wiring from casual view of an observer near the light.
Referring now to
Referring now to
Each of the sockets 50 are positioned in a downward orientation away from the reflector plate 36 so that the lamps 56 extends upwardly at the predetermined angle toward the center of the reflector plate 36. This base down orientation, i.e. base 54 is spaced radially outward and downward from the lamp 56, provides greater spacing between the sockets 50 and the bases 54 where large amounts of heat are created. It further spaces the sockets 50 and bases 54 away from the ballast housing 12 so that the ballasts 28 therein are not exposed to the direct heat of the sockets 50 and bases 54. In addition, it has been found that the arrangement of lamp assemblies 52 in the base down, diagonally upward extending configuration provide other advantages including a high level of total efficiency, decrease in uplight measured in the 90 to 180 degree range, decrease in the glare zone, which is measured in the 60 to 90 degree range and an increase in the useful zone measured in the 0 to 60 degree range. Further, because the lamps extend radially inward and upward from the sockets 50, the heat generated by the lamps is also spaced from the reflector 30 which may be plastic and susceptible to high heat deterioration.
The following tables indicate the advantages of the luminaire optical system 10. Table 1 indicated that the instant invention increases useful light, reduces glare and reduces uplight as compared to prior art competitive luminaires. In this example, Applicant's luminaire is compared to the prior art competitor luminaires of a competitor. The testing was performed with eight lamps having an output of 25,600 Lumens. Applicant's luminaire has a useful light output in the 0 to 60 degree range of 14,431 lumens which is greater than the two prior art outputs indicated. Accordingly, Applicant's Luminaire optical system 10 has a 27% advantage over
Prior art product A and 41% advantage over prior art product B. Applicant's luminaire also has decreased glare, light in the range of 60-90 degrees. Applicant's luminaire has a glare output of 2525 Lumens in the range of 60 to 90 degrees. To the contrary the prior art luminaires have respective glare outputs of 4103 and 3294. Such measurements represent a 39% decrease and 23% decrease in glare respectively. This has an end result in less eye strain to those in the area of the luminaire 10. Finally, Applicant's luminaire has an output of 3001 lumens in the uplight range of 90 to 180 degrees. To the contrary, the prior art devices have outputs of 5626 and 3931 respectively. Accordingly, Applicant's invention represents a decrease in uplight of 10% and 3% respectively. Thus, Table 1 indicates the significant improvements in the luminaire optical system versus prior art devices due to the base down, upwardly and inwardly extending lamp assemblies 52 configuration.
Likewise, Table 2 is included to show the luminaire optical system operation of the present embodiment at increased ambient temperature. In the example, the ambient temperature is 40 degrees Celsius (104 degrees Fahrenheit) and the maximum allowable temperatures are shown next to the measured temperatures of the luminaire 10 components.
As shown in Table 2, the measured temperatures are less than the maximum allowable temperatures for operation at 40° C. ambient temperature. Thus, Applicant's luminaire is operable in higher ambient temperatures than the prior art devices, which are certified for maximum ambient temperature of 25° C. The base down, upward and inwardly (reverse tilt) extending lamp configuration also provides spacing of the sources of largest amounts of heat for the luminaire 10. The location of the sockets 50 relative to the reflector 30 reduce the hotspots on the acrylic reflector 30 and lens 31. Accordingly, the system 10 will operate at higher ambient temperatures, within the maximum temperature rating (40 degrees Celsius) allowed for certification.
The luminaire optical system 10 has the further advantage of increasing ballast life up to 10 years. It is believed that a 10° C. decrease in operating temperature provides 50% increase in life at 40° C. ambient temperature.
The lumen output of the fixture may be improved by use of reflective materials for the components of the luminaire 10 within the reflector 30. For example, the stems 40 and bolts 34 may be formed of reflective materials or may have a reflective coating similar to the reflectance of polished aluminum.
Referring now to
Alternatively, the luminaire optical system 70 may further comprise a grill 80 connected to the rim 72 of the reflector 30. The grill 80 is shown in
Referring now to
Depending from the reflector top 132 are a plurality of stems 140. Three stems 140 depend from the lower surface of the reflector top 132. As previously described, the stems 140 depend from the reflector top 132 at an angle from a vertical axis. The stems 140 have an upper end attached to the reflector top 132 and a lower end connected to the lamp assembly 152.
The lamp assemblies 152 are oriented in a base down reverse tilt configuration. In addition, as shown in
Referring now to
The foregoing description of an embodiment has been presented for purposes of illustration. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed, and many modifications and variations are possible in light of the above teaching. It is intended that the scope of the invention be defined by the claims appended hereto.
