USRE40171E1 - Tubular barrel-shaped flashlight having rotatable switching assembly and focusing and defocusing capability - Google Patents

Abstract

A flashlight in accordance with the present invention includes a chamber, end cap, head assembly and lamp holder assembly. The end cap includes a bowed tripod portion to facilitate standing the flashlight on a flat surface. The head assembly includes a reflector and a lens. In one embodiment of the invention, the head assembly includes an elliptical reflector. In accordance with another embodiment of the present invention, the flashlight having a elliptical reflector is matched with a negative or planar lens. In accordance with another embodiment of the present invention, the head assembly includes an hyperbolic reflector. In accordance with another embodiment of the present invention, the flashlight having a hyperbolic reflector is matched with a positive or planar lens. In accordance with another aspect of the present invention, the flashlight includes electrode connections which prevent the conduction of electrical energy from batteries which are improperly aligned within the flashlight. In another embodiment, the lamp holder assembly includes a lamp socket having a lamp guide which provides a guide for installing lamp bulbs into the lamp socket and also provides a secure position for the lamp bulb. In another embodiment, the lamp holder assembly further includes a fluorescent coating or additive which illuminates light in otherwise dark conditions, thereby facilitating lamp replacement in the less than desirable light conditions. In another embodiment, the flashlight comprises a head assembly attached to the chamber which is rotatable relative to the chamber to cause electrical coupling of a lamp and one or more batteries retained by a chamber. In another embodiment of the flashlight, the spare lamp is held secure by the lamp holder assembly until the user of the flashlight rotates the lamp holder assembly to align a spare lamp opening with the spare lamp.

Description

This application is a continuation-in-part of application Ser. No. 09/013,078 filed Jan. 26, 1998; now U.S. Pat. No. 6,354,715.

FIELD OF THE INVENTION

The present invention relates to the field of flashlights and more specifically to hand held portable battery operated flashlights.

BACKGROUND OF THE INVENTION

Flashlights generally include a battery chamber having an end cap for retaining one or more batteries, a light bulb electrically connected to the one or more batteries and a reflector for reflecting the light from the light bulb in a particular direction. The electrical connection between the batteries and the light bulb usually includes a switch mechanism for selectively providing electrical energy from the batteries to the light bulb and, therefore enabling the flashlight to be turned on and off. The primary function of flashlights is to provide a convenient portable storable light source which is capable of projecting light in a particular direction.

Some flashlights are capable of focusing and defocusing light projected by the flashlight by allowing the light bulb to be moved within the reflector along the reflector's optical axis. The reflector is typically a parabolic shaped reflector because such a reflector provides a theoretical focus of the light when the light bulb is positioned at the parabolic reflector's focal point. In this regard, light rays emanating from a light bulb positioned at the focal point of a parabolic reflector are reflected parallel to the parabolic reflector's optical axis. Referring toFIG. 1A, a light beam dispersion is shown from a parabolic reflector with a light bulb positioned at the focal point of the parabolic reflector. In contrast, as shown inFIG. 1B, when the light bulb is moved away from the parabolic reflector's focal point, light rays reflected by the parabolic reflector diverge (i.e., defocus) leaving a glaring light void about the center of the reflected light rays and decreasing the light gathered from the light bulb.

The electrical energy to enable a flashlight to operate is usually provided by one battery, or two or more batteries in series arrangement, held within the battery chamber of the flashlight. When the charge in the batteries is depleted, a user will typically replace the batteries by removing the end cap, removing the old batteries from the battery chamber, inserting new batteries into the battery chamber, and replacing the end cap. However, when replacing multiple batteries in a flashlight, the possibility arises that a user may improperly position the batteries in a nonseries arrangement. For example, a user may improperly align the new batteries such that the positive poles of the batteries face each other, or may comingle the old batteries with the new batteries and misalign a new battery with an old battery. Misaligning the batteries may have undesired consequences, for example explosion causing physical injury, to a user of the flashlight.

Additionally, batteries often naturally emit hydrogen gas. As such, when batteries are contained within the flashlight's battery chamber, the possibility arises that hydrogen gas emitted by the batteries may become trapped within the flashlight. In some circumstances, a defective battery will emit high quantities of hydrogen gas. As a consequence, hydrogen gas may accumulate within the flashlight, thus raising the possibility of undesired consequences to a user of the flashlight, for example explosion causing physical injury.

Finally, parts of the flashlight sometimes require replacement. For example, the flashlight's light bulb will require replacement when the light bulb's filament burns out, which is often discovered when the flashlight is needed (e.g., when there are no other sources of light, including for example electrical power outages which occur at night or darkness when camping outdoors). Flashlights usually include a spare light bulb positioned on the interior of the end cap. Replacing a burned out bulb with a bulb positioned on the end cap is difficult, especially in low or no light conditions. For example, during a power outage, replacing the light bulb in a typical flashlight would require a user to remove the end cap, locate and grasp a small spare light bulb on the end cap without allowing the batteries to fall out of the flashlight, replace the end cap, remove the head assembly, replace the burned out bulb and replace the head assembly, all in darkness.

SUMMARY OF THE INVENTION

It is an objective of the present invention to provided an improved flashlight having improved switching and focusing capabilities.

It is another objective of the present invention to provide an improved flashlight which maximizes the light gathered from a light bulb, optimumly focuses the gathered light into a projected light beam and minimizes the light void within the light beam throughout the range of focus.

In accordance with one embodiment of the present invention, an improved flashlight is provided having an end cap, chamber, head assembly and lamp holder assembly. In one embodiment of the invention, the head assembly includes an elliptical reflector to increase the amount of light reflected by the flashlight when a light source is positioned within the elliptical reflector. Preferably, the elliptical reflector has an eccentricity value of no less than about 0.80 and no more than about 0.99. Preferably, the elliptical reflector has a vertex curvature value of no less than about 2.0 and no more than about 5.2. In one arrangement, the elliptical reflector has an eccentricity value of about 0.96 and a vertex curvature of about 3.1.

In accordance with another embodiment of the present invention, a flashlight having an elliptical reflector is matched with either a negative or concave lens, or a flat or planar lens. In this regard, the focusing and light gathering characteristics of the flashlight are optimized when the flashlight's elliptical reflector is matched with a negative or flat lens. Preferably, the flashlight's elliptical reflector is matched with a lens having an effective focal length no, greater than about −2.5″. In one arrangement, an elliptical reflector having an eccentricity value of about 0.96 and a vertex curvature of about 3.1 is matched with a lens having an effective focal length of about 0″.

In accordance with another embodiment of the present invention, the head assembly includes a hyperbolic reflector to increase the amount of light reflected by flashlight when a light source is positioned within the reflector. Preferably, the hyperbolic reflector has an eccentricity value of no less than about 1.01 and no more than about 1.25. Preferably, the hyperbolic reflector has a vertex curvature value of no less than about 2.0 and no more than about 7.0. In one arrangement, the hyperbolic reflector has an eccentricity value of about 1.04 and a vertex curvature of about 3.3.

In accordance with another embodiment of the present invention, a flashlight having a hyperbolic reflector is matched with either a positive or convex lens, or a flat or planar lens. In this regard, the focusing and light gathering characteristics of the flashlight are increased when the flashlight's hyperbolic reflector is matched with a positive or flat lens. Preferably, the hyperbolic reflector is matched with a lens having an effective focal length no less than about 2.5″. In one arrangement, a hyperbolic reflector having an eccentricity value of about 1.04 and a vertex curvature of about 3.3 is matched with a lens having an effective focal length of about 0″.

It is another objective of the present invention to provide a flashlight with an improved electrical connection between the batteries and the light source. In accordance with another embodiment of the present invention, the flashlight includes electrode connections which substantially reduce the likelihood that electrical energy will be conducted from batteries which are improperly aligned within the flashlight. In this regard, the electrode connection intended to contact the negative pole of the battery includes a non-conductive portion at the center of the electrode connection and a conductive portion at the perimeter of the electrode connection. As such, in the circumstance wherein a battery is inserted into the flashlight with the positive pole facing the electrode connection, the positive pole will only contact the non-conductive portion, and not the conductive portion, of the electrode connection. Additionally, the electrode connection intended to contact the positive pole of the battery includes a conductive spring having a nonconductive coating. As such, in the circumstance wherein a battery is inserted into the flashlight with the negative pole facing the electrode connection, the negative pole only will contact the nonconductive coated portion.

It is another objective of the present invention to provide a flashlight with a light holder assembly that facilitates lamp bulb replacement. In one embodiment of the present invention, the lamp holder assembly includes a lamp socket having a lamp guide which provides a guide for installing lamp bulbs into the lamp socket and also provides a secure position for the lamp bulb. In accordance with one embodiment of the present invention, the guide facilitates replacing lamps in less than desirable light conditions, as well as protects the lamp from receiving impact shocks when the flashlight is jarred.

It is another objective of the present invention to provide a flashlight capable of maintaining a spare lamp bulb in close proximity to the flashlight's light bulb thus providing for the efficient and easy replacement of the lamp bulb when needed. In accordance with one embodiment of the present invention, the flashlight includes a lamp holder assembly which includes a notch for receiving and holding a spare lamp. As such, a spare lamp is easily accessible by simply removing the head assembly from the chamber and all that is required to replace the lamp bulb, is removal of the lamp bulb in the lamp socket, removing the spare lamp, and inserting the spare lamp into the lamp socket. Preferably, the lamp holder assembly further includes a fluorescent coating or additive which illuminates light in otherwise dark conditions, thereby facilitating lamp bulb replacement in less than desirable light conditions.

In another embodiment, the flashlight comprises a chamber for retaining one or more batteries, a lamp, electrical coupling for holding said lamp and selectively electrically coupling the lamp and one or more batteries, and a head assembly attached to the chamber and rotatable relative to the chamber to cause the electrical coupling to selectively electrically couple the lamp and one or more batteries retained by the chamber. In this regard, the lamp holder assembly moves inside the chamber when the flashlight is turned “off” or “on.” The lamp holder assembly includes a lamp holder, a conductive spring, a switch plate, a detent lever, a detent ball a switch contact, a spring contact, a conductive strip, and a strip support. When assembled, the lamp holder assembly is secured axially and rotatable relative to the chamber. The head portion of the flashlight is assembled to the chamber by attaching the assembled head assembly to the chamber such that the lamp is positioned within the first central opening of the reflector. As a consequence, the head assembly is removably attached to the chamber. When fully seated, the head assembly engages the switch plate, and the rotation of the head assembly will cause the lamp holder assembly to rotate. The lamp holder assembly is rotatable among three detents. The first occurs when the head assembly is removed or attached to the chamber. The second occurs when the head assembly is in the “off” position. The third occurs when the head assembly is in the “on” position. The detents are caused by the detent ball being positioned in one of three slots formed on the outer edge of the chamber. As a result, the flashlight is moveable between the “on” and “off” detent positions by the radial movement of the head assembly. The switch contact does not contact the conductive strip in the “off” position. The switch contact contacts the conductive strip in the “on” position. The “on” detent occurs when the detent ball rolls to a second slot on the outer edge of the chamber. Notably, the detent mechanism is physically separated from the switching mechanism.

In another embodiment of the flashlight, the spare lamp is held secure by the lamp holder assembly until the user of the flashlight rotates the lamp holder assembly to align a spare lamp opening with the spare lamp.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A shows a light beam dispersion from a parabolic reflector with a light source positioned at the focal point of the reflector.

FIG. 1B shows a light beam dispersion from a parabolic reflector with a light source defocused ⅓ the distance from the focal point to apex of the reflector curvature.

FIG. 2 is a perspective view of a flashlight in accordance with the present invention.

FIG. 3 is an exploded perspective view illustrating the assembly of the flashlight of FIG.2.

FIG. 4 is an exploded side view of the end cap, chamber, lamp holder assembly and head assembly.

FIG. 5 is a cross-section view of the flashlight down the center of the flashlight ofFIG. 2 as taken through the plane indicated by2-2.

FIG. 6A is an exploded perspective view of the interior of the end cap.

FIG. 6B is a cross-section view of the end cap through the plane indicated by2-2.

FIG. 7A is an exploded perspective view of the head assembly.

FIG. 7B is a partial cross-section of the head assembly ofFIG. 7A as taken through the plane indicated by7-7.

FIG. 8A is an exploded view of the lamp holder assembly.

FIG. 8B is a partial cross-section of the lamp holder assembly ofFIG. 8A as taken through the plane indicated by8-8.

FIGS. 9A and 9B are cross-section views of the flashlight ofFIG. 2 as taken through the plane indicated by2-2 showing aligned and misaligned batteries, respectively.

FIG. 10 is a perspective view of the lamp holder assembly positioned within the chamber.

FIG. 11 is partial cross-section of the head portion of the flashlight ofFIG. 2, as taken through the plane indicted by2-2, showing the flashlight in the “off” position.

FIG. 12 is partial cross-section of the head portion of the flashlight ofFIG. 2, as taken through the plane indicted by2-2, showing the flashlight in the “on” position.

FIGS. 13A and 13B show the results of simulations for a variety of eccentricity values.

FIG. 14A shows the lamp prior to being inserted into the lamp socket.

FIG. 14B shows the lamp inserted into the lamp socket.

FIG. 14C shows a spare lamp removed from the notch which holds the spare lamp.

FIG. 15A is a front view of the lamp holder assembly when the head assembly is removed from the chamber.

FIG. 15B is a front view of the lamp holder assembly when the head assembly is attached to the chamber.

FIG. 16 is an exploded perspective view illustrating the assembly of the flashlight ofFIG. 2 having the alternative lamp holder assembly.

FIG. 17 is an exploded side view of the end cap, chamber, alternative lamp holder assembly and head assembly.

FIG. 18 is a cross-section view of the flashlight, having the alternative lamp holder assembly, down the center of the flashlight ofFIG. 2 as taken through the plane indicted by2-2.

FIG. 19 is a partial cross-section of the head assembly ofFIG. 7A as taken through the plane indicted by7-7, showing a different shaped guide to accommodate the alternative lamp holder assembly.

FIG. 20 is an exploded view of the alterative lamp holder assembly.

FIG. 21 is a partial cross-section of the lamp holder assembly ofFIG. 20 as taken through the plane indicated by20-20.

FIG. 22A is a perspective view of the alternative lamp holder assembly positioned within the chamber with the detent lever and switch plate shown apart from the lamp holder assembly.

FIG. 22B is a perspective view of the alternative lamp holder assembly fully assembled to the chamber.

FIG. 22C is a side view of the perspective view shown in FIG.22A.

FIG. 23 is a front view of the alternative lamp holder assembly (without the switch plate) at the second end of the chamber, showing the position of the alternative lamp holder assembly when the head assembly is capable of being attached or removed from the second end of the chamber.

FIG. 24 is a front view of the alternative lamp holder assembly (without the switch plate) at the second end of the chamber, showing the position of the alternative lamp holder assembly when the flashlight is in the “off” position.

FIG. 25 is a front view of the alternative lamp holder assembly (without the switch plate) at the second end of the chamber, showing the position of the alternative lamp holder assembly when the flashlight is in the “on” position.

FIG. 26 is a front view of the alternative lamp holder assembly (without the switch plate) at the second end of the chamber, showing the position of the alternative lamp holder assembly which exposes the spare lamp.

FIG. 27 is a perspective view of the alternative lamp holder assembly positioned within the chamber with the detent lever and switch plate shown apart from the lamp holder assembly.

DETAILED DESCRIPTION

Referring toFIGS. 2 through 5, aflashlight10 in accordance with one embodiment of the present invention is shown having achamber20,end cap30,head assembly40 andlamp holder assembly50. Thechamber20 includes an interior portion for holding twobatteries60,62 in a series arrangement, openings at afirst end210 and asecond end220, a first o-ring230 positioned at thefirst end210, and a second o-ring240 positioned at thesecond end220. Referring additionally toFIGS. 6A and 6B, theend cap30 includes a bowedtripod portion310 to facilitate standing theflashlight10 on a flat surface,interior threads320 and aconductive disk330. Referring additionally toFIGS. 7A and 7B, thehead assembly40 includes ahead piece410, a first o-ring420, abezel430, areflector440, a second o-ring450 and alens460. Thehead piece410 includes afirst end411, acircular tab412 located within thehead piece410 at thefirst end411, guides413, asecond end414 and lugs415 located within thehead piece410 at thesecond end414. Thereflector440 includes a reflective surface on the reflector's440 interior, a firstcentral opening442, a secondcentral opening444 substantially opposite the firstcentral opening442,wings446, andouter threads448. Preferably, thereflector440 consists of a durable synthetic material, such as that offered by General Electric Company under the name ULTEM. Thebezel430 includes afirst end431,inner threads432 at thefirst end431 which thread to the reflector's440outer threads448, a recessedcircular tab433 at thefirst end431, asecond end434, and acircular tab435 at thesecond end434. Thelens460 is positioned at the perimeter of thefirst end431 of thebezel430. The exterior of theflashlight10 consists of a metal or durable synthetic material. For example, the exterior of theflashlight10 can consist of a polycarbonite, or acrylonitrile-butadiene-styrene, or the polycarbonite offered by General Electric Company under the name CYCOLOY.

Thechamber20, which is shown inFIG. 5 holding twobatteries60,62, is enclosed at thefirst end210 by theend cap30 and at thesecond end220 by thehead assembly40. Referring toFIGS. 4-8, theend cap30 is removably attached to thechamber20 at thefirst end210 to selectively uncover the interior portion of thechamber20 for inserting or removing thebatteries60,62. In this regard, thechamber20 includes threading250 on the exterior surface at thefirst end210 of thechamber20 for engaging theinterior threads320 on theend cap30. The first o-ring230 provides a snug attachment when theend cap30 is threaded to thechamber20.

Thelamp holder assembly50 includes two embodiments. In either embodiment, thelamp holder assembly50 is positioned at thesecond end220 of thechamber20. In the first embodiment, thelamp holder assembly50 does not move inside thesecond end220 of thechamber20 when theflashlight10 is turned “off” or “on.” In this regard and referring toFIGS. 8A and 8B, thelamp holder assembly50 includes alamp holder510, aconductive spring520, aswitch lever530, asecond lever540, aswitch spring550, aswitch contact560, asecond spring570, aspring holder580, aconductive strip590 and astrip support592. Thespring holder580 includes aspring tab582,first tab584,second tab586, and a firstconductive contact588. Preferably, thespring holder580 includes anotch589 wherein a hydrogen catalyst can be placed to absorb hydrogen gas emitted by thebatteries60,62. As shown inFIG. 10, when assembled to thechamber20, thelamp holder assembly50 does not extend beyond thesecond end220 of thechamber20. Referring toFIGS. 3,4,8A,8B and10, thelamp holder assembly50 is assembled to thechamber20 by first attaching theconductive spring520 to thespring holder580. Thespring holder580 includes aspring tab582 which engages and retains a portion of theconductive spring520. Thespring holder580 andconductive spring520 are next attached to thesecond end220 of thechamber20. In this regard, thespring holder580 includes afirst tab584 and asecond tab586 for engaging thesecond end220 of thechamber20. Thechamber20 includes anend guide260, and theend guide260 includes a first recessedtab262 for engaging thefirst tab584, and a second recessedtab263, for engaging thesecond tab586. ReferencingFIG. 10, attachment of thespring holder580 andconductive spring520 to thesecond end220 occurs by inserting thespring holder580 and attachedspring520 in thefirst end210 of thechamber20 and moving thespring holder580 toward thesecond end220 of thechamber20 until the first recessedtab262 engages thefirst tab584 and the second recessedtab263 engages thesecond tab586.

Thelamp holder510, with theswitch lever530 andsecond lever540 assembled on thelamp holder510, is next inserted into thesecond end220 of thechamber20. Thelamp holder510 includestabs511, aswitch slot512 and asecond slot513. Theswitch lever530 includestabs532 andslots534, and thesecond lever540 includestabs542 andslots544. The switch lever's530slots534 mate with theswitch slot512 to allow theswitch lever530 to slide along theswitch slot512. The second lever's540slots544 mate with thesecond slot513 to allow thesecond lever540 to slide along thesecond slot513. ReferencingFIGS. 3,5,8A,8B and10, thelamp holder510 is next partially inserted into thesecond end220 of thechamber20 by aligning theswitch slot512 with the first slotted opening264 of theend guide260, and thesecond slot513 with the second slotted opening266 of theend guide260. Once partially inserted, theswitch lever530 andsecond lever540 are spring loaded onto thelamp holder510 by inserting theswitch spring550 andsecond spring570, and aligning and engaging the switch lever's530slots534 with theswitch slot512 and aligning and engaging the second lever's540slots544 with thesecond slot513. With theswitch lever540 andsecond lever550 depressed, thelamp holder510 is fully seated into thesecond end220 of thechamber20. As a result, as shown inFIG. 10, the switch lever's530tabs532 and the second lever's540tabs542 engage thechamber20 atpoints514. As shown inFIG. 5, the lamp holder's510tabs511 engage the interior of thechamber20. ReferencingFIGS. 3,8A and10, theswitch slot512 engages the recessedtab265 of theend guide260 and thesecond slot513 engages the recessed tab267 of theend guide260. Preferably, thelamp holder assembly510 snap fits to thechamber20. ReferencingFIG. 11, thelamp holder510 encloses thespring tab582, further securing theconductive spring520 to thespring holder580. ReferencingFIG. 11, thespring holder580 does not contact the interior of thechamber20. ReferencingFIG. 10, thelamp70 extends from thesecond end220 of thechamber20 when thelamp70 is installed into thelamp holder assembly50.

Referring toFIGS. 7A and 7B, thehead assembly40 is assembled by first inserting thereflector440 intofirst end431 of thebezel430 and threading the reflector's440threads448 to the bezel's430inner threads432. The second o-ring450 is next inserted into the circular recessedtab433 and thelens460 is fixedly attached to thebezel430 by pressing thelens460 into the circular recessedtab433. The o-ring450 allows for secure attachment between thelens460 and thebezel430. Preferably, thelens460 snap fits to thebezel430. The first o-ring420 is next placed over the circular table435 at thesecond end434 of thebezel430, and thesecond end434 of thebezel430 is inserted intofirst end411 of thehead piece410 with thewings446 of thereflector440 aligned with theguides413 of thehead piece410. When thesecond end434 of thebezel430 is fully inserted into thefirst end411 of thehead piece410, the bezel's430circular tab434 engages the head piece's410circular tab412, and thewings446 of thereflector440 engage theguides413 of thehead piece410. As a result, thebezel430 is only allowed to rotate relative to the head piece410 (i.e., radially) and cannot move away from the head piece410 (i.e., axially). Preferably, thebezel430 snap fits to thehead piece410. As a result of thewings446 of thereflector440 engaging theguides413 of thehead piece410, thereflector440 moves within thebezel430 axially when thebezel430 is moved radially.

The head portion of theflashlight10 is assembled by attaching the assembledhead assembly40 to thechamber20, having thelamp holder assembly50 assembled in thechamber20, such that thelamp70 is positioned within the firstcentral opening442 of thereflector440. In this regard, thehead assembly40 is removably attached to thechamber20 at thesecond end220.FIGS. 10 and 15A show thelamp holder assembly50 assembled in thechamber20 when the head assembly is removed from thechamber20. Thechamber20 includes theend guide260 formed on the exterior surface at thesecond end220 of thechamber20. ReferencingFIGS. 3 and 10, theend guide260 includespaths261 which engage thelugs415 on thehead piece410. Thelugs415 are aligned withpaths261, and thehead assembly40 is guided in thedirection287 until thehead assembly40 is fully seated on thesecond end220 of thechamber20. Thehead assembly40 is then rotated in thedirection288 to a first detent, which is caused by theswitch lever530 being positioned between two of theguides413. Theflashlight10 is in the “off” position at this position. In this position, thehead assembly40 is only permitted to rotate relative to the chamber20 (i.e., radially) and cannot move away from the chamber20 (i.e., axially). The second o-ring240 provides a secure attachment between thehead assembly40 and thechamber20.

When fully assembled and holdingbatteries60,62 in proper alignment, theflashlight10 is capable of selectively electrically coupling thelamp70 to thebatteries60,62. Thechamber20 includes aconductive strip590 along the length of thechamber20, between thefirst end210 and thesecond end220. Theconductive strip590 is supported at thefirst end210 of thechamber20 by thestrip support592. Referring toFIGS. 6A and 6B, theend cap30 includes anonconductive area340. ReferencingFIG. 8, when theend cap30 is attached to thechamber20, theconductive disk330 is electrically connected to theconductive strip590 atpoint593. Theconductive disk330 electrically connects the negative contact of thebattery60 to theconductive strip590 when thebattery60 is properly aligned in thechamber20 as shown in FIG.9A. Thenonconductive area340 prevents electrical connection when thebattery60 is improperly aligned in thechamber20 as shown in FIG.9B. In this regard, the positive contact of an improperly alignedbattery60 only contacts thenonconductive area340 and does not contact theconductive disk330, due to theopening331, as shown in FIG.6A.

Thelamp holder assembly50 selectively electrically connects thelamp70 to properly positionedbatteries60,62 in accordance with the radial movement of thehead assembly40. ReferencingFIG. 11, theflashlight10 is shown in the “off” position. ReferencingFIGS. 3,10 and12, theflashlight10 is moved to the “on” position by rotating thehead assembly40 in thedirection288. The head portion of theflashlight10 can be disassembled by rotating thehead assembly40 from the “off” position in a direction opposite288 and disengaging thehead assembly40 from thechamber20 alongpaths261.

Referring toFIGS. 8-12,14A,14B,14C and15, the510 includes alamp socket515 for holding alamp70 having afirst pin72 andsecond pin74 and alamp guide516. When the head portion of theflashlight10 is assembled, thelamp guide516 does not contact thereflector440. In this regard, thereflector440 is prevented from contacting thelamp guide516 bystop436 as shown in FIG.11. Thelamp guide516 is a guide which facilitates aligning thefirst pin72 andsecond pin74 of thelamp70 with thelamp socket515 when thelamp70 is being installed. Thelamp guide516 also provides a secure position for thelamp70 by supporting a part of the outer portion of thelamp70 when thelamp70 is installed. As such, thelamp guide516 facilitates replacing alamp70 in less than desirable light conditions, as well as protects thelamp70 from receiving impact shocks from thereflector440 when theflashlight10 is jarred. Additionally, thelamp holder510 is capable of receiving and holding aspare lamp71. In this regard, thelamp holder510 includes anotch517 which is capable of receiving aspare lamp71.

As shown inFIG. 15B, thespare lamp71 in thenotch517 is covered by the switch lever's530tab532 when the head portion of theflashlight10 is assembled. As shown inFIG. 15A, thespare lamp71 in thenotch517 becomes uncovered by the switch lever's530tab532 when thehead assembly40 is disassembled from thechamber20. As such, as shown inFIGS. 10,14A,14B,14C,15A and15B, thespare lamp71 is easily accessible by removing thehead assembly40 from thechamber20, thereby making thespare lamp71 held by thelamp holder510 accessible. In this regard, all that is required to replace thelamp70, is removal of thelamp70 from thelamp socket515, removing thespare lamp71 from thenotch517, and installing thespare lamp71 into the lamp socket52. Preferably, theinsulated lamp holder510 includes a phosphorescent coating or additive, which illuminates light in otherwise dark conditions, thereby facilitating lamp replacement in less than desirable light conditions.

ReferencingFIGS. 8A,8B,9A and9B, thefirst pin72 is electrically connected to theswitch sprin550 byconductive contact551, and thesecond pin74 is electrically connected to thespring520 by the firstconductive contact588, when thelamp70 is positioned inlamp holder assembly50. Theconductive spring520 includes anportion521 having a nonconductive coating and atail522. As shown inFIG. 9A, thetail522 contacts the positive pole of thebattery62 when thebattery62 is properly aligned in thechamber20. As shown inFIG. 9B, theportion521 having a nonconductive coating prevents electrical contact with an improperly alignedbattery62. In this regard, the negative pole of an improperly alignedbattery62 only contacts a nonconductive portion ofconductive spring520 and does not contact a conductive portion, thereby preventing electrical connection and removing the possibility of a catastrophic event due to reverse polarization.

Referring toFIGS. 5,8A,8B,11 and12, theswitch lever530 is moveable between the “on” and “off” positions when the head portion of theflashlight10 is assembled. Theswitch lever530 includes aswitch contact560 having anedge561. Theswitch contact560 is electrically connected to theswitch spring550. ReferencingFIG. 11, theflashlight10 is shown in the “off” position. In this position, theswitch lever530 is fully extended due to theswitch lever530 being position positioned between two of theguides413 within thehead piece410. As a consequence, theswitch lever530 does not electrically connect theedge561 to theconductive strip590 atpoint594. Moreover, theswitch lever520530 in fully extended position provides a detent to maintain theflashlight10 in the “off” position untilflashlight10 is moved to the “on” position. ReferencingFIG. 12, theflashlight10 is in the “on” position. In this position, theswitch lever530 is compressed due to theswitch lever530 contacting one of theguides413 within thehead piece410. As a consequence, theswitch lever530 electrically connects theedge561 to theconductive strip590 atpoint594. In the “on” position, thesecond lever540 is positioned between two of theguides413 within thehead piece410. In this regard, as the head assembly is turned in thedirection288 from the “off” position, thesecond lever540 will no longer contact one of theguides413, and will become fully extended due to thesecond lever540 being position positioned between two of theguides413 within thehead piece410. Thesecond lever540 becoming fully extended provides a detent to maintain theflashlight10 in the “on” position untilflashlight10 is moved to the “off” position. Preferably, thehead assembly40 is rotatable about thirty degrees between the “off” and “on” positions.

The movement of thelamp70 within thereflector440 to focus and defocus the light emanating from thelamp70 is independent from the radial movement of thehead assembly40 to turn theflashlight10 “on” or “off.” When assembled, as shown inFIGS. 11 and 12, thelamp70 is positioned within the interior of thereflector440 through the firstcentral opening442 of thereflector440. As such, rotating thebezel430 relative to thehead piece410 causes thereflector440 to move within thebezel430 axially relative to thehead piece410. As a result, thereflector440 moves relative to thelamp70, and such movement allows for the light emanating from thelamp70 to be focused by positioning thelamp70 at the reflector's440 focal point, or defocused by positioning thelamp70 away from the reflector's440 focal point.

As indicated above and with reference toFIGS. 16-27, thelamp holder assembly50 includes a second embodiment, thelamp holder assembly500, which moves inside thesecond end220 of thechamber20 when theflashlight10 is turned “off” or “on.” ReferencingFIG. 20, thelamp holder assembly500 includes alamp holder610, aconductive spring620, aswitch plate630, adetent lever640, adetent ball650, aswitch contact660, aspring contact670, aconductive strip690, and astrip support692. Thelamp holder assembly500 is assembled to thechamber20 by first attaching theconductive spring620 to thelamp holder610. Thelamp holder610 includes a spring tab (not shown) which engages and retains a portion of theconductive spring690 and holds theconductive spring690 in contact with thespring contact670, as is shown in FIG.21. Thelamp holder610 and attached conductive spring are next positioned at thesecond end220 of thechamber20. ReferencingFIG. 18, thelamp holder610 includes atab612 for contacting a portion of the interior of thechamber20 near thesecond end220 atarea614. Positioning of thelamp holders610 and attachedconductive spring620 occurs by inserting thelamp holder610 and attachedspring620 in thefirst end210 of thechamber20 and movinglamp holder610 toward thesecond end220 of thechamber20 until thetab612 engages the interior of thechamber20 at the atarea614. Thelamp holder610 further includes a tab (not shown) which is aligned with a correspond slot (not shown) in the interior of thechamber20 to ensure that thelamp holder610 and attachedspring620 are properly positioned at thesecond end220 of thechamber20. Thelamp holder610 is shown positioned at thesecond end220 of thechamber20 inFIGS. 22A and 27.

ReferencingFIGS. 22A,22B,22C and27, with thelamp holder610 exposed at thesecond end220 of thechamber20, thelamp holder assembly500 is assembled. In this regard, thedetent ball650 is positioned on thelamp holder610 at theguide611 and thedetent plate640 is next positioned onto thelamp holder610 with the detent plate ball opening642 positioned on thedetent ball650 and theslots644 aligned with the threadedopenings612 on thelamp holder610. Theswitch plate630 is next positioned withopenings631 aligned with the threadedopenings612. Thelamp holder assembly500 is completely assembled by inserting screws (not shown) through theopenings631, threading the screws to threadedopenings612, and securing theswitch plate630 to thelamp holder610. As a result, thelamp holder assembly500 is secured axially and rotatable at thesecond end220 of thechamber20.

As described above and with general reference toFIG. 18, the head portion of theflashlight10 is assembled by attaching the assembledhead assembly40 to thechamber20 having thelamp holder assembly500 assembled in thechamber20, such that thelamp70 is positioned within the firstcentral opening442 of thereflector440. In this regard, thehead assembly40 is removably attached to thechamber20 at thesecond end220.FIG. 22B shows thelamp holder assembly500 assembled in thechamber20 when thehead assembly40 is removed from thechamber20. Thechamber20 includes theend guide260 formed on the exterior surface at thesecond end220 of thechamber20. Theend guide260 includespaths261 which receive and guide thelugs415 on thehead piece410 when thehead assembly40 is attached to and removed from thechamber20. Thelugs415 are aligned withpaths261, and thehead assembly40 is guided in thedirection287 until thehead assembly40 is fully seated on thesecond end220 of thechamber20. Detachment of thehead assembly40 occurs by moving thehead assembly40 in the direction opposite287 until thehead assembly40 is removed.FIG. 23 shows the position of the lamp holder assembly500 (without switch plate) when thehead assembly40 is capable of being attached to or removed from thechamber20. ReferencingFIGS. 23 and 27, the lamp holder assembly is positioned at a first detent, which is caused by thedetent ball650 being positioned in afirst slot652 on the outer edge of thechamber20 at thesecond end220.

When fully seated, theguides413 of thehead assembly40 engage the slots634 on theswitch plate630, and the rotation of thehead assembly40 will cause thelamp holder assembly500 to rotate. Thehead assembly40 is then rotated in thedirection288 to a second detent, which is caused by thedetent ball650 being positioned in asecond slot652 on the outer edge of thechamber20 at thesecond end220. Theflashlight10 is in the “off” position at this position.FIG. 24 shows the position of the lamp holder assembly500 (without switch plate) when thehead assembly40 is in the “off” position. In this position, thehead assembly40 is only permitted to rotate relative to the chamber20 (i.e., radially) and cannot move away from the chamber20 (i.e., axially). The head portion of theflashlight10 can be disassembled by rotating thehead assembly40 from the “off” position in a direction opposite288 to the first detent, and disengaging thehead assembly40 from thechamber20 alongpaths261.

When fully assembled and holdingbatteries60,62 in proper alignment, theflashlight10 is capable of selectively electrically coupling thelamp70 to thebatteries60,62. ReferencingFIG. 20, thechamber20 includes aconductive strip690 along the length of thechamber20, between thefirst end210 and thesecond end220. Theconductive strip690 is supported at thefirst end210 of thechamber20 by thestrip support692. Thelamp holder assembly500 selectively electrically connects thelamp70 to properly positionedbatteries60,62 in accordance with the radial movement of thehead assembly40. ReferencingFIG. 21, thefirst pin72 is electrically connected to theswitch spring620 byspring contact670, and thesecond pin74 is electrically connected to theswitch contact660, when thelamp70 is positioned inlamp holder assembly500. Referring toFIGS. 16-22, theflashlight10 is moveable between the “on” and “off” positions by the radial movement of the head assembly in thedirection288. As shown inFIG. 24, theswitch contact660 does not contact theconductive strip690 in the “off” position. As shown inFIG. 25, theswitch contact660 contacts theconductive strip690. In this regard, as thehead assembly40 is rotated in thedirection288, thelamp holder assembly500 is rotated as well. The “on” detent occurs when the detent ball rolls to athird slot652 on the outer edge of thechamber20 at thesecond end220. Notably, the detent mechanism is physically separated from the switching mechanism. Preferably, thehead assembly40 is rotatable about thirty degrees between the “off” and “on” positions. The movement of thelamp70 within thereflector440 to focus and defocus the light emanating from thelamp70 is independent from the radial movement of thehead assembly40 to turn theflashlight10 “on” or “off” as described previously.

Thespare lamp71 is held secure by theswitch plate630, until the user of theflashlight10 rotates thelamp holder assembly500 to align the spare lamp opening632 with thespare lamp71. ReferencingFIG. 23, the lamp holder assembly500 (without switch plate) is shown in the position when thehead assembly40 is removed from thechamber20. From this position, thespare lamp opening632 is aligned with thespare lamp71 by rotating the lamp holder assembly in the direction oppositedirection288.FIG. 26 shows the position of the lamp holder assembly500 (without switch plate) when thespare lamp opening632 is aligned with thespare lamp71. Once aligned, thespare lamp71 is removable from thelamp holder assembly500.

Notably, thereflector440 andlens460 combination accomplishes one of the objectives of the present invention, namely to provide improved light gathering from thelamp70, optimum focus spot and minimal light void within the light projected by thereflector440 throughout the range of the lamp's70 movement within interior of thereflector440. In this regard, one embodiment of the present invention usesconic reflectors440 other than a parabolic reflector.

The vertex curvature (i.e., the actual shape) of thereflector440 is determined using the following equation for a Vertex Cartesian coordinate system:
f(r)=Cr²/(1+√(1−SC²r²)),  (1.1)
wherein C is the vertex curvature, r is the radial distance from the cylindrical center of the optic, and S is equal to unity minus the square of the eccentricity. In this regard, it was discovered that the use of nonparabolic reflectors minimized the light void which is apparent when a parabolic reflector was used, as shown in FIG.1B. Additionally, it was also discovered that matching nonparbolic reflectors with an appropriate lens curvature optimized the direction of the rays emanating from the nonparabolic reflector. For elliptical reflectors (i.e., 0<eccentricity<1), it was determined that the use of a negative or a flat lens caused a more uniform and intense ray pattern when the light source was placed at the optimum optical focal point. For hyperbolic reflectors (i.e., eccentricity>1), it was determined that the use of a positive or flat lens caused a more uniform and intense ray pattern when the light source was placed at the optimum optical focal point.

Referring to the table shown inFIGS. 13A and 13B, a series of simulations were run using the equation 1.1, wherein the eccentricity ranged from 0.8 to 1.25. The criteria for the results shown inFIGS. 13A and 13B were as follows: (i) a reflector aperture (i.e., the size of the reflector's44 second central opening49) of 1.4375″; (ii) a reflector opening (i.e., the size of the reflector's44 first central opening48) of 0.19″; (iii) a maximum lighted spot size of 29″ to be illuminated by theflashlight10 at a distance of 120″; (iv) a minimum light void through out the range of focus (i.e. the movement of thelamp70 along the reflector's440 optical axis from about the reflector's440 focal point to the point thelamp70 exits thereflector440 at either the firstcentral opening442 for a elliptical reflector or the secondcentral opening444 for a hyperbolic reflector); (v) a maximum range of motion of thelamp70 throughout the range of focus of no grater than about 0.25″; (vi) a minimum angle of subtended light gathered by the reflector of about 100 degrees; and (vii) a lens with effective focal length of no less than about +2.5″ or no greater than −2.5.

For each given eccentricity and lens combination, the vertex curvature was adjusted to attain the minimum focused spot size and void throughout the range of focus and the maximum subtended angle of light gathered by thereflector440. This was performed for each value of eccentricity by taking a sample of lenses with effective focal lengths of no less absolute value than about 2.5″, running simulations wherein the vertex curvature was increased until no void appeared when thelamp70 was completely defocused (i.e. thelamp70 exits thereflector440 at either the firstcentral opening442 for a elliptical reflector, or the secondcentral opening444 for a hyperbolic reflector). The value of vertex curvature was not increased beyond what which was reasonably necessary to remove the void, because increasing the vertex curvature further reduced the potential magnification of the lamp's70 light beam as thelamp70 was moved away from the focal point of thereflector440.

In view of the simulations and the criteria specified, the elliptical reflector, preferably has an eccentricity value of no less than about 0.80 and no more than about 0.99. Preferably, the elliptical reflector has a vertex curvature value of no less than about 2.0 and no more than about 5.2. In one arrangement, the elliptical reflector has an eccentrically value of about 0.96 and a vertex curvature of about 3.1. In one embodiment of the present invention, aflashlight10 having an elliptical reflector is matched with a negative or flat lens. Preferably, an elliptical reflector is matched with a lens having an effective focal length of no greater than about −2.5″ and no more than about 0″. In one arrangement, an elliptical reflector44 having an eccentricity value of about 0.96 and a vertex curvature of about 3.1 is matched with a lens45 having an effective focal length of about 0″.

In accordance with another embodiment of the present invention, thehead assembly40 includes a hyperbolic reflector. Preferably, the hyperbolic reflector has an eccentricity value of no less than about 1.01 and no more than about 1.25. Preferably, the hyperbolic reflector has a vertex curvature value of no less than about 2.0 and no more than about 7.2. In one arrangement, the hyperbolic reflector has an eccentricity value of about 1.04 and a vertex curvature of about 3.3. In another embodiment, aflashlight10 having a hyperbolic reflector is matched with a positive or flat lens. Preferably, a hyperbolic reflector is matched with a lens having an effective focal length no less than about 2.5″. In one arrangement, ahyperbolic reflector440 having an eccentricity value of about 1.04 and a vertex curvature of about 3.3 is matched with alens460 having an effective focal length of about 0″.

The foregoing description of the present invention has been presented for purposes of illustration and description. The description is not intended to limit the invention to the form disclosed herein. Consequently, the invention and modifications commensurate with the above teachings and skill and knowledge of the relevant art are within the scope of the present invention. It is intended that the appended claims be construed to include all alternative embodiments as permitted by the prior art.

Claims (16)

1. A flashlight comprising:

(a) chamber means for retaining at least one battery;

(b) a lamp;

(c) electrical coupling means for holding said lamp and selectively electrically coupling said lamp and said at least one battery retained by said chamber means;

(d) a head piece attached to said chamber means and solely rotatable radially relative to said chamber means;

(e) a reflector for reflecting light from said lamp;

(f) a bezel attached to said head piece and solely rotatable radially relative to said head piece;

wherein said bezel is rotatable to cause said reflector to axially move relative to said chamber means;

wherein said head piece is rotatable to cause said electrical coupling means to selectively electrically couple said lamp and said at least one battery retained by said chamber means.

2. A flashlight as claimed inclaim 1, wherein said bezel is rotatable in a first direction relative to said head piece to cause said reflector to move away from said chamber means and rotatable in a second direction relative to said chamber means to cause said reflector to move towards said chamber means.

3. A flashlight as claimed inclaim 1, wherein said coupling means comprises:

a lamp holder assembly for holding said lamp;

wherein the rotation of said head piece relative to said chamber means causes said lamp holder assembly to rotate to cause said electrical coupling means to electrically couple said lamp and said at least one battery retained by said chamber means.

4. A flashlight as claimed inclaim 1, said flashlight further comprises:

detent means for providing a first detent position whereto said head piece is capable of being rotated to and removably fixed;

wherein said head piece is rotatable to said first detent position to cause said electrical coupling means to selectively electrically couple said lamp and said at least one battery retained by said chamber means;

wherein said detent means is structurally independent of said electrical coupling means.

5. A flashlight as claimed inclaim 1, said flashlight further comprises:

detent means for providing a first detent position whereto said head piece is capable of being rotated to and removably fixed;

wherein said head piece is rotatable to said first detent position to cause said electrical coupling means to selectively electrically couple said lamp and said at least one battery retained by said chamber means;

wherein said detent means is structurally part of said electrical coupling means.

6. A flashlight which is portable and hand held, and which is capable of operating with at least one battery, said flashlight comprising:

(a) a chamber for retaining at least one battery, wherein said chamber comprises a first opening for receiving one or more batteries; and a second opening substantially opposite said first opening;

(b) an end cap removably connected to said chamber for selectively covering and uncovering said first opening;

(c) a light bulb source;

(d) means for holding said light bulb source, said means for holding said light source retained by said chamber at said second opening;

(e) coupling means for selectively electrically coupling said means for holding a light bulb source and said at least one battery retained in said chamber;

(f) a conic reflector comprising a first central opening, a second central opening substantially opposite said first central opening, and an inner area defined by the space between said first central opening and said second central opening;

(g) a lens;

(h) head assembly means for positioning said lens and said reflector relative to said light bulb source when said head assembly means is connected to said second opening of said chamber;

wherein said head assembly means further comprises (i) a head piece which is solely rotatable radially relative to said chamber to cause said coupling means to selectively electrically couple said means for holding a said light bulb source and said at least one battery retained in said chamber, and (ii) a bezel which is solely rotatable relative to said head piece to cause said reflector to axially move relative to said light bulb source.

7. A flashlight as claimed inclaim 6, wherein said head assembly means holds said lens a fixed distance from said light bulb source when said bezel is rotated.

8. A flashlight as claimed inclaim 6, wherein said head assembly means comprises a first portion and a second portion;

wherein said first proton is rotatable relative to said chamber to cause said coupling means to selectively electrically couple said means for holding a lamp bulb said light source and said at least one battery retained in said chamber;

wherein said head assembly means second portion is rotatable relative to said first portion to cause said conic reflector to move relative said lamp light source.

9. A flashlight as claimed inclaim 8, wherein said first portion is a head piece and said second portion is a bezel.

10. A flashlight as claimed inclaim 6, wherein said head assembly means fixedly positions said lens relative to said light bulb source and moveably positions said reflector relative to said light bulb source.

11. A flashlight comprising:

(a) chamber means for retaining at least one battery;

(b) a lamp;

(c) coupling means for selectively electrically coupling said lamp and said chamber means; and

(d) a head assembly comprising:

a reflector having a first central opening, a second central opening substantially opposite said first opening, and an inner area between said first central opening and said second central opening;

a lens;

a head piece rotatable relative to the chamber means to cause said coupling means to selectively electrically couple said lamp and said chamber means;

a bezel rotatable relative to said head piece such that the position of said lamp may be varied within said inner area of said reflector to focus and defocus light illuminated by said lamp.

12. A flashlight comprising:

(a) chamber means for retaining at least one battery;

(b) lamp holder means for holding a lamp;

(c) electrical coupling means for selectively electrically coupling said chamber means and said lamp holder means;

(d) a reflector;

(e) a head piece that is rotatably secured to said chamber means so that said head piece may rotate relative to said chamber means without axial movement of said head piece relative to said chamber means to cause said electrical coupling means to selectively electrically couple said chamber means and said lamp holder means; and

(f) a bezel that is rotatably secured to said head piece so that said bezel may rotate relative to said chamber means without axial movement of said bezel relative to said head piece to cause said reflector to move axially relative to said lamp.

13. A flashlight comprising:

(a)a chamber for retaining at least one battery;

(b)a lamp holder assembly for retaining a lamp, positioned at least partially within said chamber;

(c)a head assembly attachable to said chamber for retaining a reflector, wherein rotation of said head assembly causes electrical coupling of said lamp and said battery;

(d)a bezel rotatable relative to said chamber, wherein solely radial rotation of said bezel causes the light emanating from said lamp to focus and defocus.

14. A flashlight comprising:

(a)a chamber for retaining at least one battery;

(b)a lamp holder assembly for retaining a lamp, positioned at least partially within said chamber;

(c)a head assembly attachable to said chamber for retaining a reflector, said reflector adapted to receive said lamp, wherein rotation of said head assembly causes electrical coupling of said lamp and said battery;

(d)a bezel rotatable relative to said chamber and operably connected to said reflector, wherein solely radial rotation of said bezel causes axial movement of said reflector relative to said lamp.

15. A flashlight comprising:

(a)a chamber for retaining at least one battery, said chamber having a first end portion and a second end portion;

(b)a lamp positioned at said first end portion of said chamber;

(c)a switch assembly positioned between said lamp and said battery wherein movement of said switch assembly electrically couples said lamp to said battery;

(d)a reflector adapted to receive said lamp;

(e)a bezel rotatable relative to said chamber and operably connected to said reflector, wherein solely radial rotation of said bezel causes axial movement of said reflector relative to said lamp.

16. A flashlight comprising:

(a)a chamber for retaining at least one battery, said chamber having a first end portion and a second end portion;

(b)a lamp positioned at said first end portion of said chamber;

(c)a head piece attachable to said chamber;

(d)a reflector adapted to receive said lamp;

(e)a bezel rotatable relative to said chamber and operably connected to said reflector, wherein rotation of said bezel relative to said chamber causes axial movement of said reflector relative to said lamp, but does not cause axial movement of said bezel relative to said lamp.

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