This invention relates to a portable, reduced-emissions work light. The invention has particular application for military use in special purpose tents, referred to as modular command post units (MCPU), and other mobile military shelters, such as lightweight maintenance enclosures (LME). The invention meets military requirements for electromagnetic interference (EMI) emissions, and includes shock-absorbing components which protect the light from damage caused by dropping or other sudden impact. The invention is light weight and has a convenient handle at one or both ends. In addition, the invention includes snap-together components which enable quick and convenient assembly and disassembly.
Therefore, it is an object of the invention to provide a portable, hand-held work light which generates reduced emissions.
It is another object of the invention to provide a work light which is especially applicable for military use, and which meets military specifications for EMI emissions.
It is another object of the invention to provide a work light which does not interfere with the performance of equipment which may be potentially sensitive to low frequency magnetic fields.
It is another object of the invention to provide a work light which is relatively lightweight.
It is another object of the invention to provide a work light which includes snap-together components for ready assembly and disassembly.
It is another object of the invention to provide a work light which enables convenient and safe removal and replacement of a defective or inoperative ballast.
It is another object of the invention to provide a work light which generates a minimum of five-foot candles of light at 30 inches off the ground.
It is another object of the invention to provide a work light which is impact resistant.
It is another object of the invention to provide a mobile shelter, such as a military MCPU and LME, which includes one or more reduced emissions work lights.
It is another object of the invention to provide a mobile shelter which includes an energy efficient lighting system.
These and other objects of the present invention are achieved in the preferred embodiments disclosed below by providing a reduced emissions work light. The work light comprises a bulb including an elongated bulb tube. A handle is provided adjacent the bulb, and is adapted for being gripped by a user to manipulate the work light. An emissions containment housing is located within the handle. A ballast is located within the housing, and is operatively connected to the bulb. An emissions filter is located within the housing, and is operatively connected to the ballast. The filter and housing cooperate to reduce emissions generated by the work light.
According to another preferred embodiment of the invention, a tubular, light-transmitting protective shield surrounds the bulb tube to protect the bulb from damage.
According to yet another preferred embodiment of the invention, a cylindrical shock-absorbing plug is positioned within the protective shield and engages a free end of the bulb tube to further protect the bulb from damage.
According to yet another preferred embodiment of the invention, the plug includes an interior web for being gripped to remove the plug from the protective shield.
According to yet another preferred embodiment of the invention, a shock-absorbing end cap is positioned over an end of the protective shield opposite the handle.
According to yet another preferred embodiment of the invention, a switch opening is formed in the emissions containment housing to accommodate a ballast activation switch in the handle.
According to yet another preferred embodiment of the invention, a removable color filter is positioned over the protective shield to filter light emitted by the bulb.
According to yet another preferred embodiment of the invention, a power supply cord is adapted for being connected to a power source to supply electrical power to the work light.
According to yet another preferred embodiment of the invention, an emissions insulating sheath is provided over the power supply cord to further reduce emissions generated by the work light.
In another embodiment, the invention is a reduced emissions work light including a flourescent bulb with electrode pins, a pin base, and an elongated bulb tube extending outwardly from the pin base. A handle is provided adjacent the bulb, and is adapted for being gripped by a user to manipulate the work light. An emissions containment housing is located within the handle. The housing comprises a hollow cylindrical metal ballast cup. A ballast is located within the cup and is operatively connected to the bulb. A ballast activation switch is accessible through an opening formed in the cup to activate the ballast at the handle. An emissions filter is located within the cup and is operatively connected to the ballast. The filter and housing cooperate to reduce emissions generated by the work light.
According to another preferred embodiment of the invention, the ballast includes electrical wires having respective terminal ends operatively connected to respective pins of the flourescent bulb.
According to yet another preferred embodiment of the invention, a bulb socket is located between the flourescent bulb and the ballast. The bulb socket defines a plurality of longitudinal through-bores receiving respective wire ends of the ballast from a first end thereof and respective electrode pins of the bulb from an opposite second end thereof.
According to yet another preferred embodiment of the invention, the bulb socket includes enlarged conical openings at its first end. The enlarged openings are adapted for receiving respective electrode pins into the longitudinal through-bores.
According to yet another preferred embodiment of the invention, the bulb socket is formed of a molded plastic material.
According to yet another preferred embodiment of the invention, a cylindrical resilient shock is formed around the bulb socket at an open proximal end of the cup.
According to yet another preferred embodiment of the invention, the resilient shock includes an inwardly-tapered guide recess adapted for guiding the pins of the bulb into the through-bores of the bulb socket.
In yet another embodiment, the invention is a reduced emissions work light including a bulb with an elongated bulb tube. A perforated, emissions insulating screen surrounds the bulb tube. A handle is adjacent the bulb, and is adapted for being gripped by a user to manipulate the work light. An emissions containment housing is located within the handle. A ballast is located within the housing, and is operatively connected to the bulb. An emissions filter is located within the housing, and is operatively connected to the ballast. The filter, housing, and screen cooperate to reduce emissions generated by the work light.
According to yet another preferred embodiment of the invention, a light reflector is located adjacent the bulb tube for enhancing illumination of the bulb.
According to yet another preferred embodiment of the invention, an elongated pull strip is releasably attached to the bulb for removing the bulb from the work light for replacement.
In yet another embodiment, the invention is a reduced emissions work light including a bulb with an elongated bulb tube. A perforated, emissions insulating screen surrounds the bulb tube. A light-transmitting protective shield surrounds the bulb tube and screen to protect the bulb from damage. A handle is provided adjacent the protective shield, and is adapted for being gripped by a user to manipulate the work light. An emissions containment housing is located within the handle. A ballast is located within the housing, and is operatively connected to the bulb. An emissions filter is located within the housing, and is operatively connected to the ballast. A power supply cord is adapted for being connected to a power source to supply electrical power to the work light. The power supply cord includes an emissions insulating sheath. The filter, housing, screen, and sheath cooperate to reduce emissions generated by the work light.
In yet another embodiment, the invention is a mobile shelter system erected to create a covered interior. The shelter system includes one or more portable reduced-emissions work lights adapted for illuminating the interior of the shelter system.
Some of the objects of the invention have been set forth above. Other objects and advantages of the invention will appear as the description proceeds when taken in conjunction with the following drawings, in which:
Referring now specifically to the drawings, a reduced emissions work light according to the present invention is illustrated in
Referring to
The bulb shield 15 of the work light 10 is formed of a transparent, high-impact plastic. As shown in
A flexible pull strip 41 is located inside the bulb shield 15 for use in re-lamping the work light 10. The pull strip 41 is formed of a non-conductive, chrome-finished polymer material. One end of the pull strip 41 includes a reinforced portion with pin holes 42 adapted for receiving the electrode pins 34 of the bulb 30. The opposite end of the pull strip 41 extends slightly beyond the free end of the bulb 30 for convenient access. With a free end of the bulb shield 15 uncovered, the bulb 30 is removed from the work light 10 by gripping the end of the pull strip 41 and pulling in a direction away from the handle 12. The pull strip 41 is further described in Applicant's issued patent, U.S. Pat. No. 5,738,438, incorporated herein by reference.
As shown in
Referring to
To facilitate proper placement of the bulb 30, the shock 62 has opposing, inwardly-tapered side walls 67 and 68 defining a guide recess for directing the bulb pins 34 into the through-bores 64 of the socket 61. The lower perimeter 69 of the guide recess is preferably contoured to secure the pin base 33 of the bulb 30. The mouth 71 at each through-bore 64 of the socket 61 defines an enlarged, generally conical opening adapted to readily accept the bulb pins 34. In addition, because the socket 61 is formed of a hard molded plastic, the bulb pins 34 engage the socket 61 at the enlarged conical openings and slide into respective through-bores 64 without friction interference. While the bulb socket 61 is preferably molded separately inside the rubber shock 62, as described and shown, the bulb socket 61 and shock 62 may be integrally-formed together as a single unit. A longitudinal channel 72 is formed along one side of the shock 62 to accommodate passage of the power supply cord 16 through the interior of the work light 10.
Referring again to
Referring to
For convenient assembly and disassembly, the components of the work light 10 include complementary snap-together attachment elements enabling ready access to and replacement of worn or damaged parts. In addition, all surface elements of the work light 10 are preferably non-conductive. The term non-conductive is defined as having sufficient dielectric to be considered non-conductive at voltages below 600 V AC. The work light 10 may also include one or more hanger hooks (not shown) for suspending the light from overhanging support structure inside the tent or enclosure.
A reduced emissions work light is described above. Various details of the invention may be changed without departing from its scope. Furthermore, the foregoing description of the preferred embodiment of the invention and the best mode of practicing the invention are provided for the purpose of illustration only and not for the purpose of limitation—the invention being defined by the claims.
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Number | Date | Country | |
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20020172037 A1 | Nov 2002 | US |