Portable lighting device

Information

  • Patent Grant
  • 6231208
  • Patent Number
    6,231,208
  • Date Filed
    Thursday, August 12, 1999
    25 years ago
  • Date Issued
    Tuesday, May 15, 2001
    23 years ago
Abstract
A portable lighting device according to the present invention includes a battery housing, a light source supported at a first end of the battery housing, and a shroud extending outward from the first end of the battery housing circumferentially around the light source. The shroud is preferably formed of a translucent material having a partially reflective inner surface for reflecting a portion of incident light emitted from the light source in a forward direction while allowing a portion of the incident light to be transmitted through the shroud and dispersed in peripheral directions. The shroud further preferably includes a diffusing outer surface for diffusing the incident light that is transmitted through the shroud. A shroud is preferably integrally formed with a collar portion as used for threading the integrated head structure onto the battery housing. Additionally, a protective lens cover that may include a collimating lens is also integrally formed in this head structure. Thus, the portable lighting device of the present invention may be constructed with much fewer components and at a much lower cost than conventional flashlights.
Description




BACKGROUND OF THE INVENTION




The present invention generally relates to a lighting device. More particularly, the present invention relates to a portable battery-powered lighting device.




Portable lighting devices, such as flashlights and lanterns, are known which produce a directional beam of light.

FIG. 1

shows the construction of a relatively low-cost flashlight


10


currently marketed by the assignee of the present invention. Conventional flashlight


10


includes a battery housing


12


of a molded plastic construction, which further serves as a handle for holding the flashlight. As shown in

FIG. 1

, battery housing


12


has a generally cylindrical shape with one end having an integrally molded end wall


13


. The open end of battery housing


12


, in which batteries may be inserted or removed, includes external threads


14


for engaging the internal threads


16


of a shroud


18


. Battery housing


12


further includes a slot


20


formed in a side thereof in order to enable a raised portion


22


of a sliding electrical contact


24


to be secured to a switch


26


provided on the exterior of battery housing


12


.




Flashlight


10


further includes a spring


28


that is inserted within the battery compartment defined by battery housing


12


. Spring


28


is provided in contact with the end wall


13


to bias the inserted batteries forward into contact with a positive terminal


30


of a light bulb


32


. Spring


28


further provides an electrical contact to the negative terminal of the rearmost battery inserted into battery housing


12


. A fixed electrical contact


34


is also provided within the battery compartment of battery housing


12


to provide an electrical connection between spring


28


and a moving electrical contact


24


.




Flashlight


10


further includes a bulb holder


36


having internal threads


38


for engaging external threads provided as a negative electrical contact


40


of light bulb


32


. Bulb holder


36


also includes either external threads


42


or a welding surface for securing bulb holder


36


within an aperture


44


provided in an electrical contact shell


46


. With such an arrangement, the negative contact terminal


40


of light bulb


32


is electrically coupled through holder


36


to contact shell


46


. At the same time, with light bulb


32


screwed into bulb holder


36


, positive terminal


30


extends beyond the rearward opening of holder


36


so as to come into contact with a positive terminal of the forwardmost inserted battery. To turn light bulb


32


on and off, switch


26


is slid axially along battery housing


12


thereby moving sliding contact


24


forward and rearward into and out of contact with contact shell


46


.




Flashlight


10


additionally includes a reflector


48


having a central aperture for receiving light bulb


32


such that light emitted from light bulb


32


is reflected in a generally forward direction. A lens


50


is provided across the forward opening of the flashlight as defined by shroud


18


and reflector


48


to protect the light bulb from damage. The lens


50


, reflector


48


, contact shell


46


, light bulb


32


, and bulb holder


36


, which together form a head structure of flashlight


10


, are secured across the open end of battery housing


12


by shroud


18


, which includes a lip at its forward end to prevent lens


50


and the components positioned to its rear from falling out of the forward end of shroud


18


.




Although flashlight


10


represents a relatively low-cost flashlight, it nevertheless includes no less than eleven components. Further, due to the number of potential component interfaces through which water could penetrate to reach the interior of battery housing


12


, flashlight


10


would not be considered a waterproof flashlight.




Although conventional lanterns and flashlights such as that described above are well-suited for brightly illuminating a relatively small area, they are not well-suited for providing wide area illumination like that produced by a lighting device designed for area illumination, such as a table lamp or gas lamp. Such area lamps, however, are not well-suited for directing a beam of light to illuminate an area a considerable distance away. Because of the need in the market for lighting devices that may serve as both a directional light and an area light, various devices have been constructed that will perform both of these functions. In some of these lighting devices, separate light sources and lenses are provided that may be independently activated. An example of one such light is disclosed in commonly assigned U.S. patent application Ser. No. 08/690,287. Because two separate switches or a multi-position switch is required to selectively power the separate light sources, and because separate light chambers and lenses must be integrated within the device, these devices tend to be much more complex, bulky, and expensive.




To provide a less complex and less expensive portable lighting device that may function as both a directional light source and an area light, the assignee of the present invention has previously developed a two-in-one portable lighting device that utilizes a single light source, and hence, a single on/off switch. An example of such a lighting device is disclosed in British Patent No. 2,242,732 B. These lighting devices include a two-part housing in which a first part of the housing contains the batteries, the switch, and the light source, and a second part of the housing includes two separate chambers. The first and forwardmost chamber is a directional lighting chamber, and the second chamber is defined by a cylindrically shaped diffusing lens integrated within the cylindrical body of the second part of the housing. The second part of the housing may thus be slid axially along the first housing to reposition the light source within one of the two light chambers. Thus, a user may use such a lighting device as a directional light by sliding the second part of the housing fully within the first part of the housing such that the light source is pushed through a small opening within a reflector of the directional light chamber. Then, to use the device as an area light, the user may fully extend the first part of the housing such that the light source is removed from the directional light chamber into the area light chamber where the light emitted therefrom is transmitted through the cylindrical diffusing lens. Although these portable lighting devices are less expensive and bulky than the portable lighting devices that utilize two separate light sources, they nevertheless remain relatively complex and expensive compared to a conventional flashlight. Furthermore, because the single light source may only be in one chamber at any one time, the portable lighting device may not be simultaneously used as a directional light source and an area lamp. Therefore, there exists a need for a portable lighting device that may operate simultaneously as an area light and a directional light while being easily manufactured at a significantly lower cost.




SUMMARY OF THE INVENTION




An aspect of the present invention is to provide a portable lighting device that may function as both a directional light source and an area light. Still another aspect of the present invention is to provide a portable lighting device that simultaneously functions as both a directional light source and an area light using only a single light source.




To achieve these and other aspects and advantages, the portable lighting device of the present invention comprises a battery housing, a light source supported at a first end of the battery housing, and a shroud extending outward from the first end of the battery housing circumferentially around the light source, the shroud being formed of a translucent material and having a partially reflective inner surface for reflecting a portion of incident light emitted from the light source in a forward direction while allowing the portion of the incident light to be transmitted through the shroud and dispersed in peripheral directions.




It is an additional aspect of the present invention to provide a portable lighting device that is low in cost and easy to assemble. It is a further aspect of the present invention to provide a portable lighting device that includes significantly less components than other portable lighting devices. Still another aspect of the present invention is to provide a portable lighting device that has less components and is waterproof.




To achieve these and other aspects and advantages, the portable lighting device of the present invention consists essentially of a battery housing having an open end and a closed end for housing at least one battery; a first electrical contact extending from the closed end of the battery housing to the open end for providing an electrical connection to a first contact of at least one battery; a light source having first and second contact terminals for receiving power from at least one battery contained in the battery housing, the light source being supported at the open end of the battery housing such that the second contact is electrically coupled to a second contact of at least one battery; an integrally formed head structure rotatably mounted to the battery housing and extending outward from the open end of the battery housing circumferentially around the light source, the head structure including an integral protective cover for the light source, and having a reflective inner surface for reflecting light emitted from the light source; a seal intermediate the head structure and the battery housing for preventing water from entering the flashlight through an interface between the battery housing and the head structure; and a second electrical contact disposed in the head structure for selectively electrically contacting the first electrical contact when the head structure is rotated to a first position relative to the battery housing and for contacting the first contact of the light source.











These and other features, advantages, and objects of the present invention will be further understood and appreciated by those skilled in the art by reference to the following specification, claims, and appended drawings.




BRIEF DESCRIPTION OF THE DRAWINGS




In the drawings:





FIG. 1

is an exploded perspective view of a conventional flashlight;





FIG. 2

is a perspective view of a flashlight constructed in accordance with a first embodiment of the present invention;





FIG. 3

is a light ray diagram illustrating the operation of a flashlight constructed in accordance with one aspect of the present invention;





FIGS. 4A-4C

are side elevational views illustrating various configurations for a flashlight constructed in accordance with the present invention;





FIG. 5

is an exploded perspective view of a flashlight constructed in accordance with a first embodiment of the present invention;





FIGS. 6A and 6B

are cross-sectional views of the head structure of a flashlight constructed in accordance with the present invention illustrating two different mechanisms for supporting a light bulb relative to the head structure;





FIG. 7

is a perspective view of a flashlight constructed in accordance with a second embodiment of the present invention;





FIG. 8

is a perspective view of a lantern constructed in accordance with the present invention; and





FIGS. 9A and 9B

are front and side perspective views of a work light constructed in accordance with the present invention.











DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS




As used and described herein, the term “forward” shall refer to the direction in which light is primarily directed when the portable lighting device of the present invention is used as a directional light source. It shall be appreciated that this term as well as others describing the relative orientation of the respective components of the present invention are used solely for the purposes of defining a relationship amongst the components and are not used to limit the invention based on its orientation within any particular environment.





FIG. 2

shows a flashlight


100


constructed in accordance with a first embodiment of the present invention. Flashlight


100


includes a battery housing


102


, which is preferably formed as a hollow cylinder for containing one or more batteries used to provide power to its light source. Battery housing


102


is preferably formed of molded plastic due to its non-corrosive and water-impervious properties as well as its low cost. Flashlight


100


further includes a head structure


110


that includes a collar portion


112


and a light directing portion


114


. As described in more detail below, the open end of battery housing


102


, as well as a rearward opening cavity defined by collar portion


112


, preferably include threads such that head structure


110


may be rotated and attached relative to battery housing


102


. As also described in more detail below, electrical contacts are provided within battery housing


102


and head structure


110


such that rotation of head structure


110


between specified positions will turn the light source on and off. As shown in

FIG. 2

, this particular configuration includes a tab


116


that extends rearward of collar portion


112


. Table


116


has a recess or aperture


118


for enabling a user to more easily rotate head structure


110


relative to battery housing


102


. Tab


116


is also provided to enable a user to quickly determine whether head structure


110


has been rotated to the on or off position.




As illustrated in

FIG. 3

, head structure


110


is preferably formed of a translucent material that allows some of the light emitted from a light source


122


to be transmitted through the walls of head structure


110


. Head structure


110


may be formed of polypropylene or other suitable materials. The light directing portion of head structure


110


, which functions as a shroud, includes a forward-facing open cavity


124


that is defined and bounded by an inner surface


120


of shroud


114


. Inner surface


120


is preferably partially reflective and partially transmissive, such that a portion of the light incident thereon is emitted from light source


122


and is reflected in a collimated fashion as a directional beam of light, while a remaining portion of the incident light is transmitted through the walls of shroud


114


. Inner surface


120


preferably includes a parabolic portion


121


located in the rearward portion of cavity


124


, with light source


122


located at the focal point of the parabola. Inner surface


120


may also include a forward portion


123


having a constant diameter.




Preferably, the exterior surface


126


of shroud


114


is textured to diffuse the light that is transmitted through the shroud walls. The reflectivity of inner surface


120


may be selectively varied by the degree of smoothness thereof. Further, the amount of diffusing of the light transmitted through the walls of shroud


114


may be varied in different portions of shroud


114


and may be varied more generally and uniformly to affect the amount of diffusion of the transmitted incident light. Thus, with reference to

FIG. 4A

, a very smooth inner surface


120


would result in a greater percentage of light being transmitted in a directional collimated beam of light while a lesser degree of smoothness would result in a higher percentage of light being transmitted peripherally through the walls of shroud


114


as illustrated in FIG.


4


B. Moreover, as shown in

FIG. 4C

, the reflectivity of the inner surface of shroud


114


may be controlled such that equal percentages of light are reflected directionally forward or transmitted through the walls of shroud


114


in peripheral directions. Thus, as apparent from the examples illustrated in

FIGS. 4A-4C

, the flashlight may be manufactured differently depending upon the primary use, such as an area light or directional light, for which the lighting device will be employed. To effectively function as both a directional light and an area light, at least ten percent (10%) of the light should be reflected directionally forward or diffused peripherally. The relative smoothness of inner surface


120


may be varied during manufacture by controlling the degree of smoothness of the corresponding surface of the mold, or by polishing inner surface


120


after head


110


is removed from the mold.




As shown in

FIG. 4B

, a leg


104


, which extends axially outward at the closed end of battery housing


102


, may be included to provide additional support such that flashlight


100


may be stood on end


103


for use as an area lamp.




By providing a shroud that is translucent in the manner described above, a lighting device functions simultaneously as a directional light and an area light while using only a single light source. With this construction, a lighting device according to the present invention may be constructed at a much lower cost than conventional lighting devices that also provide for simultaneous use as a directional light and area light.




A principal benefit of using a lighting device simultaneously as a directional light and an area light is that not only will the user be able to illuminate an area in a directional sense, but it will allow others to be able to see the user as well. Thus, the lighting device also functions as a locator light. Further, by directing light peripherally outwardly in addition to providing a collimated directional beam, users walking down a dark path may direct the directional beam a distance in front of them while still having illumination at their feet. Such peripheral illumination may be provided regardless of the rotational position of the flashlight about its central axis.




Referring back to

FIG. 3

, it is noted that head structure


110


may additionally include an integrally formed protective cover


130


that is also generally transparent and shaped in the form of a dome. Cover


130


is provided to protect bulb


122


. By integrally forming protective cover


130


with the other portions of head structure


110


, water cannot enter the flashlight assembly through the open end of cavity


124


. The forwardmost end of protective cover


130


is preferably formed as a collimating lens


132


so as to collimate the light transmitted therethrough from light source


122


. As illustrated, light that does not transmit through collimating lens


132


exits cover


130


at a sufficient angle to be incident upon a portion of the inner surface


120


of shroud


114


. Due to the partially reflective nature of inner surface


120


and due to the generally parabolic shape in which inner surface


120


is preferably formed, the reflected light is directed in a forward direction in a generally collimated beam.




Because head structure


110


is an integrally formed structure made of a single material, such as a plastic, and because the material is preferably translucent, light incident upon a rear wall


134


of shroud


114


would be partially transmitted through wall


134


and into a rearward facing cavity


136


defined by collar


112


. Because light transmitted into this rearward facing cavity


136


would provide no useful illumination since it would be unlikely to reach the exterior of the battery compartment, a reflector


138


is provided opposite inner surface


120


of wall


134


. Preferably, reflector


138


is a highly reflective aluminum or chromium coating that may be applied to rear wall


134


after head structure


110


has been molded. With reflector


138


in place, no light emitted from light source


122


is transmitted into the battery compartment. Thus, all the light from light source


122


is either reflected directionally forward or diffused peripherally outward through the walls of shroud


114


.




A more detailed view of the overall preferred construction of flashlight


100


is shown in FIG.


5


. As shown in

FIG. 5

, the forward open end of battery housing


102


includes threads


106


on an outer surface thereof for engaging threads


140


provided on an inner surface of collar portion


112


of head structure


110


. An electrical connection from the rear wall


103


to the open end of battery housing


102


is provided by an electrical connector


142


which consists of a wire that is formed into a spring


144


at an end that contacts the inner surface of end wall


103


. The other end of electrical contact


142


is terminated with a hook


146


that wraps around the edge of battery housing


102


at its open end. Hook


146


of electrical connector


142


is positioned to contact the contact ring


152


of a combined bulb holding/contact shell


150


.




Contact shell


150


is an integrally formed metallic structure having a disk-like portion


154


provided in contact with a forward edge of ring


152


. Preferably, the forward surface of the disk-like member


154


is highly polished or plated to serve as a reflector, such as reflector


138


shown in FIG.


3


. To the extent that the rear wall


134


of shroud


114


is contoured, disk-like member


154


may be similarly contoured to closely fit against wall


134


. Disk portion


154


of contact shell


150


includes a central hole


158


having a diameter larger than that of a negative contact


162


of bulb


122


and yet smaller than a radially extending ridge


164


extending at the forward end of the negative contact


162


. With this structure, bulb


122


is supported such that the light-emitting portion of the bulb extends within the forward opening cavity and the positive and negative contacts


160


and


162


, respectively, protrude rearwardly into the rearward facing cavity defined by collar portion


112


and into the battery compartment. Additionally, a plurality of notches


156


extend outwardly from central hole


158


for receiving a corresponding prong


166


extending rearwardly from rear wall


134


within the rearwardly opening cavity defined within collar


112


. By providing such a structure, contact shell


150


fits snugly within the rearwardly opening cavity of collar


112


so as to hold bulb


122


in place.




Further, in addition to performing this bulb holding function, contact shell


150


serves to provide an electrical connection between negative terminal


162


of bulb


122


and electrical connector


142


, which contacts the negative terminal of the rearmost battery provided in battery housing


102


. With head structure


110


threaded onto battery housing


102


, positive terminal


160


of bulb


122


is in constant contact with a positive terminal of a forwardmost battery provided in housing


102


. Additionally, with head structure


110


rotated onto housing


102


as far as it can go, hook


146


of electrical connector


142


is brought into contact with the inner surface of contact ring


152


thereby providing the complete electrical connection between the batteries and light bulb


122


. To disrupt the delivery of power to bulb


122


and thereby turn the flashlight off, head structure


110


is rotated thereby moving contact ring


152


outwardly from hook


146


and thereby breaking the electrical connection between the negative terminals of the batteries and the negative contact of bulb


122


.




With this structure, the additional parts for providing a switching mechanism may be eliminated, thereby significantly reducing the cost and complexity of the flashlight. Further, by integrating the electrical connector and the spring, additional parts may also be eliminated. The largest number of parts are eliminated, however, by the implementation of integrated head structure


10


, which combines all the features and functions of a shroud, lens, reflector, and bulb support in a single molded unit. Furthermore, by providing an optional O-ring, gasket, or other seal


170


at the end of battery housing


102


, the flashlight may be readily made waterproof since the only interface through which water could reach the interior of the battery would be through the interface between battery housing


102


and head structure


110


. Thus, the eleven components of the conventional flashlight shown in

FIG. 1

may be reduced to a total of five components, with an optional sixth component added to make the flashlight waterproof. As stated above, it would be very complicated to modify the conventional eleven-component flashlight to be waterproof.




In addition, by comparing the flashlights of FIG.


1


and

FIG. 5

, one can see that flashlight


100


of the present invention provides an additional feature in that it functions as an area lamp in addition to a directional flashlight. Thus, for a lower cost, a consumer may purchase a flashlight having additional functions not provided by the conventional flashlight. Referring to

FIGS. 6A and 6B

, two alternative constructions are shown for holding light bulb


122


in place relative to head structure


110


. In

FIG. 6A

, a bulb holder


174


is provided that is similar to the bulb holder/contact shell


150


shown in

FIG. 5

except that the contact ring


152


is removed and the outer diameter of shell


150


is reduced. Thus, bulb holder


174


holds the bulb in place in a similar manner as that shown in FIG.


5


. To provide electrical contact between the negative terminal portion of bulb


122


and hook


146


of electrical connector


142


, an electrically conductive and highly reflective coating


172


is formed on the rear surface of rear wall


134


as well as the interior surface area of collar


112


.




Referring to

FIG. 6B

, a combination contact shell/bulb holder


176


is illustrated that is contoured to the interior surface of the rearwardly facing cavity defined by collar


112


so as to serve as a reflector and an electrical contact. The contact shell/bulb holder


176


further includes two or more resilient tabs


178


that are biased inwardly against the bulb. It will be appreciated that resilient tabs


178


could be configured differently and made of plastic material so as to be integrally formed with the other portions of head structure


110


.




Although the present invention has been described as utilizing a fully integrated head structure


110


that includes a protective cover


130


integrated with the remaining portion of head structure


110


, it will be appreciated by those skilled in the art that protective cover


130


could be formed separately and ultrasonically welded within the forwardly facing cavity. By forming protective cover


130


separately, the remaining portion of head structure


110


may be formed using a material that is slightly more opaque, or using a colored material, whereas protective cover


130


may be made of a clear transparent material or a material of a different color.





FIG. 7

shows a flashlight


200


constructed in accordance with a second embodiment of the present invention. As shown, flashlight


200


includes a contoured and/or textured battery housing/handle


202


, which may be formed of plastic or metal and have a rubber exterior coating. Flashlight


200


further differs from flashlight


100


of the first embodiment in that a push-button toggle switch


204


is provided on head structure


210


. By providing a push-button switch


204


, head structure


210


need not be rotated relative to battery housing


202


to turn the light on and off.




Head structure


210


of flashlight


200


is preferably constructed in the same manner as head structure


110


of flashlight


100


discussed above, such that it will enable flashlight


200


to simultaneously function as an area light and a directional light. An end guard


206


may optionally be provided about the forward edge of shroud


214


. End guard


206


may be formed of an opaque plastic material or may be formed of a hard rubber material to absorb shock if the flashlight were dropped.





FIG. 8

shows a lantern


300


constructed in accordance with the present invention. Lantern


300


preferably includes a battery housing


302


having an integrally formed handle


304


. At one end, battery housing


302


includes threads for engaging the threads provided on a head structure


310


. Head structure


310


is preferably configured in a similar manner to the flashlights discussed above in that it is preferably formed of a translucent material having a highly polished, parabolically shaped interior surface for partially reflecting the light from the light bulb (not shown) and for allowing a portion of the light striking the interior surface to be transmitted through the walls of head structure


310


and diffused outwardly in peripheral directions. Because the light bulb in such lanterns typically is positioned with its bulb portion within the battery housing


302


, it is preferable to coat the backside of head assembly


310


that extends within battery housing


302


with a highly reflective material so that light transmitted through head structure


310


cannot enter into the battery compartment in the interior of housing


302


. The light source in lantern


300


may be turned on and off by providing a push-button switch in proximity to handle


304


or by rotating head structure


310


in a manner similar to that described above with respect to the flashlight of the first embodiment of the invention. To facilitate turning of head structure


310


between on and off positions, a tab


308


may be provided that protrudes outwardly from head structure


310


.




As shown in

FIGS. 9A and 9B

, the inventive concept of the present invention may be applied to a work light. Similar to conventional work lights, work light


400


includes a cage structure


404


, which serves to protect the light bulb from damage if the work light were dropped. Further, work light


400


includes a hanger


406


for hanging the work light in a location where the light will be projected onto the work area. Work light


400


differs from a conventional work light, however, in that it includes a diffusing lens


408


for diffusing light transmitted therethrough from the light source. Preferably, the inner surface of diffusing lens


408


is highly polished such that a portion of the light incident on the inner surface is reflected outwardly as a directional beam through a lens portion


410


. Lens portion


410


is provided on an opposite end of diffusing lens


408


from a battery housing


412


. The portion of diffusing lens


408


positioned closest to battery housing


412


is preferably parabolically shaped with a light bulb supported at the focal point of the parabola such that a significant amount of light from the light source is directed through lens


410


.




To facilitate the use of work light


400


as a directional light source, hanger assembly


406


is preferably pivotally mounted to cage


404


about a pair of pivot points


414


. In this manner, hanger assembly


406


may be folded down as shown in

FIG. 9B

so as to not obstruct light projected from lens


410


. Hanger assembly


406


preferably includes a hook


416


that is pivotally mounted on hanger structure support


406


on a rounded portion thereof or on a pivot pin


418


provided on support


406


.




Battery housing


412


preferably includes threads


420


for engaging threads formed in a collar portion


422


integrally formed at the lower-rearward end of diffusing lens


408


. Work light


400


may be provided with a push-button switch for turning the light source on and off or may be provided with an electrical connector structure similar to that shown in

FIG. 5

such that the light source is turned on and off by rotation of battery housing


412


relative to the head portion of work light


400


. Although work light


400


is shown as being powered by batteries, it will be appreciated by those skilled in the art that the concepts of the present invention would be equally applicable to an alternating current (AC)-powered work light or a direct current (DC) worklight that does not include such a battery housing. By providing a combination area light and directional light in a work light, a person using work light


400


may, for example, use the work light with its hanger for area illumination of the work surface and then use the same work light as a directional light to more brightly illuminate a smaller area within the larger work area. Further, by forming lens


410


, diffusing lens


408


, and collar


422


as an integral structure, and by providing an O-ring, gasket, or seal at the interface of battery compartment


412


and collar


422


, one may readily transform work light


400


into a waterproof work light.




Although the present invention has generally been described as a low-cost lighting device, it will be appreciated by those skilled in the art that various concepts described herein may be employed in various other forms of lighting devices that are more complex and more expensive without departing from the spirit and scope of the present invention. For example, the concept of utilizing a partially reflective and partially transmissive shroud may be employed in various lighting devices regardless of their expense or complexity. Similarly, it will be appreciated that a low-cost flashlight such as that shown in

FIG. 5

may be made with a relatively opaque shroud, such as a white plastic; that reflects substantially all the light emitted from the light source as a directional light beam. Although such a flashlight would not have the advantages of simultaneously operating as an area light, it would nevertheless benefit from having relatively few components and a lower manufacturing cost than conventional low-cost flashlights.




It will further be appreciated that the portable lighting devices described above may be powered by either rechargeable or non-rechargeable batteries. Further, it will also be appreciated that, if rechargeable batteries are used, the portable lighting devices could be modified to include extendible prongs for recharging the batteries without removing them from the battery housing.




The above description is considered that of the preferred embodiments only. Modifications of the invention will occur to those skilled in the art and to those who make or use the invention. Therefore, it is understood that the embodiments shown in the drawings and described above are merely for illustrative purposes and not intended to limit the scope of the invention, which is defined by the following claims as interpreted according to the principles of patent law, including the Doctrine of Equivalents.



Claims
  • 1. A portable lighting device comprising:a handle; a light source; and light directing means having a first end disposed on said handle and having an opening in a second end opposite said first end, said light directing means reflects a portion of the light emitted from said light source in a forward direction through said opening and simultaneously disperses a remaining portion of the light in other peripheral directions.
  • 2. The portable lighting device as defined in claim 1, wherein said light directing means directs at least ten percent of the light from the light source that is incident on said light directing means in the forward direction and directs at least ten percent of the light in the peripheral directions.
  • 3. The portable lighting device as defined in claim 1, wherein said light directing means includes diffusing means for diffusing the remaining portion of the light that is dispersed in peripheral directions.
  • 4. A portable lighting device comprising:a handle; a light source; and light directing means disposed on said handle for reflecting a portion of the light emitted from said light source in a forward direction and for simultaneously dispersing a remaining portion of the light in other peripheral directions, wherein said light directing means includes a shroud extending circumferentially around said light source, said shroud being formed of a translucent material and having a partially reflective inner surface for reflecting a portion of incident light emitted from said light source in the forward direction while allowing a portion of the incident light to be transmitted through said shroud and dispersed in peripheral directions.
  • 5. The portable lighting device as defined in claim 4, wherein said inner surface of said shroud has a parabolic shape.
  • 6. The portable lighting device as defined in claim 4, wherein said shroud further includes a diffusing outer surface for diffusing the incident light that is transmitted through said shroud.
  • 7. The portable lighting device as defined in claim 1, wherein said handle includes a cavity for receiving at least one battery.
  • 8. A portable lighting device comprising:a handle; a light source; and a partially reflective and partially transmissive element having a first end disposed on said handle and having an opening at a second end opposite said first end, said element reflects a portion of the light emitted from said light source in a forward direction through said opening and simultaneously disperses a remaining portion of the light in other peripheral directions.
  • 9. A portable lighting device comprising:a handle; a light source; and light directing means disposed on said handle for reflecting a portion of the light emitted from said light source in a forward direction and for simultaneously dispersing a remaining portion of the light in other peripheral directions, wherein said light directing means includes a partially reflective, partially transmissive inner surface for reflecting a portion of incident light emitted from said light source in the forward direction while allowing a portion of the incident light to be transmitted through the inner surface and dispersed in peripheral directions.
  • 10. A portable lighting device comprising:a handle; a light source; and a partially reflective and partially transmissive element disposed on said handle for reflecting a portion of the light emitted from said light source in a forward direction and for simultaneously dispersing a remaining portion of the light in other peripheral directions, wherein said partially reflective and partially transmissive element includes a partially reflective, partially transmissive inner surface for reflecting a portion of incident light emitted from said light source in the forward direction while allowing a portion of the incident light to be transmitted through the inner surface and dispersed in peripheral directions.
  • 11. The portable lighting device as defined in claim 1 and further including a lens disposed in said opening.
  • 12. The portable lighting device as defined in claim 8 and further including a lens disposed in said opening.
CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No. 08/941,340, entitled “PORTABLE LIGHTING DEVICE,” filed on Sep. 30, 1997, by David R. Dalton et al., now U.S. Pat. No. 6,004,003, the entire disclosure of which is incorporated herein by reference.

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Continuations (1)
Number Date Country
Parent 08/941340 Sep 1997 US
Child 09/372916 US