WO2006102757A1

WO2006102757A1 - A cordless rechargeable work light

Info

Publication number: WO2006102757A1
Application number: PCT/CA2006/000478
Authority: WO
Inventors: Phil Trigiani; Tony Ferraro; Richard Robert Coulson
Original assignee: Uview Ultraviolet Systems Inc.
Priority date: 2005-03-30
Filing date: 2006-03-30
Publication date: 2006-10-05

Abstract

The present invention is for a portable, cordless work light that can emply an array of lighting components, such as light emitting diodes (LEDs), within a hollow body. The work lights are of durable construction providing impact and shock resistance and provide a rugged switch and light source. In addition, the work light provides many stable and predicable resting surfaces adaptable to many different work environments. The work light is designed with modular components which facilities replacing components when they become damaged.

Description

TITLE OF THE INVENTION A CORDLESS RECHARGEABLE WORK LIGHT

FIELD OF INVENTION

[0001] The present invention relates to portable lights and in particular, to a cordless rechargeable work light containing light emitting diodes.

BACKGROUND OF THE INVENTION

[0002] Service technicians are often required to perform repair services in areas that are difficult to access and are poorly lit and commonly employ work lights to provide additional illumination in these areas. The work lights are placed in a variety of positions in the work area to direct a sufficient amount of additional light into a work space. Such lights need to be relatively compact and portable, yet they must be able to provide light in sufficient quantity, with a large enough beam to be concentrated upon the part or element being repaired. These devices are well known by such names as work lights, trouble lights, utility lights, inspection lights and the like.

[0003] In the past, incandescent light bulbs, housed in a protective housing have generally been used as a source of illumination in work lights. More recently, new light sources have been developed, such as fluorescent bulbs, halogen bulbs and light emitting diodes. However, incandescent and halogen lamps have a thin filament wire located inside a glass or quartz enclosure. The filament is relatively not well unsupported inside the bulb and can be easily damaged by shocks or impacts. Such work lights function only as long as the filament is intact. Both incandescent and halogen lights also produce a substantial amount of heat creating a potential hazard when used around volatile fluids and gases, for example gasoline.

[0004] Fluorescent lamps have also been used in work lights. Fluorescent lamps are constructed within a thin glass tube having a desired shape. The inside of the tube is coated with a phosphor and the tube is filled with a gas that forms plasma when energized by electricity. Electrons, energized by electricity, are emitted from the plasma energizing the phosphor coating which then emits light. The anode and cathode elements of a fluorescent bulb are somewhat more shock resistant than an incandescence filament but they are still subject to breakage. Fluorescent tubes require a ballast for light production. A significant amount of space is required to accommodate these ballasts. Thus, portable fluorescent lights are significantly larger when the ballast is included inside the body of the lamp. Fluorescent lamps need large voltages to convert gas into plasma to produce electrons and therefore draw a lot of power. If powered by a battery, the battery must have a large capacity, or must be replaced often.

[0005] In most work lights, the internal components such as switches are not easily accessible. Thus, in case of damage or failure, most work lights need to be completely disassembled to repair and replace damaged components or they are discarded. Known work lights usually have a mechanical switch to activate the light which is usually located in-part on the outer body of the light. Such switches are typically constructed of mechanically moving parts either in the form of a push button, toggle, slide or rocker. These types of switches have mechanisms that are electrically conductive and are subject to damage from severe impacts when lights are dropped or impacted by other objects. If the conductive components are broken or damaged, the lights do not function. Moreover, switch contacts can become dirty or corroded which also prevents the light from functioning properly. The switch components, light source element and lens are components that are the most frequently broken or damaged. The lens often becomes scratched from sharp edges, clouded when in contact with corrosive chemicals or broken from impact

[0006] New work lights that are lightweight, durable and easily repaired are always needed. In addition, useful work lights should be easily positioned for use by the user.

SUMMARY OF THE INVENTION

[0007] The present invention is for a portable, cordless work light that can employ an array of lighting components, such as light emitting diodes (LEDs), within a hollow body. The work lights are of durable construction providing impact and shock resistance and provide a rugged switch and light source. In addition, the work light provides many stable and predicable resting surfaces and are adaptable for use in many different work environments. The work light is designed with modular components which facilitates replacing components when they become damaged.

[0008] In an embodiment the work light is housed in a hollow body having a handle portion, providing a firm grip area, and a lighting portion. Optionally, the lighting portion provides for light passage from the internal light source to a work surface, optionally through a replaceable lens.

[0009] The hollow body has an opening at one or at each end of the body. A removable cap covers each opening. A positional hook can be attached to the body. In one embodiment, the hook can be manipulated from a storage position within a cavity on the outside of the hollow body, to provide for hanging the light. A switch, such as a mechanical plunger switch, can be located opposite the lens on the lighting portion of the hollow body. The plunger in conjunction with a control device can activate and deactivate the work light after being temporarily depressed.

[0010] Inside the hollow body, the light source can contain an array of LEDs arranged on printed circuit board (PCB) support panel. The LEDs can be grouped together in any suitable pattern that provides a sufficient light intensity for a work area. In an embodiment, a control device in the form of an electronic PCB panel can be mechanically and electrically connected to an LED support panel located parallel to and behind the LED PCB support panel using known connectors. The electronic control PCB panel contains a microprocessor that controls the electrical operation of the work light.

[0011] Any durable light source is suitable for use in the present work lights. However, LEDs are generally preferred because LEDs use very low power, and produce small amounts of heat compared to incandescent, halogen and fluorescent lights. LEDs are generally fabricated with the light source component completely encapsulated in a plastic epoxy, preventing breakage due to an impact or shock. Because of the low power requirements, a battery source can be small in size and still supply a sufficient amount of energy. This minimizes the weight and improves the portability and utility of the present lights.

[0012] In an embodiment a power source, such as a battery or an array of rechargeable battery cells electrically joined together forming a single battery pack, is located in the hollow body, such as in the handle portion. It can be positioned below an LED support panel and an electronic control panel. Suitable battery sources can provide sufficient electrical energy to drive the LEDs and other electronic components. By employing a battery pack as the power source, the present work light does not require an electrical power cord for operation. As a result, the work light can be used with greater freedom, such as in vehicles where electrical outlets do not exist.

[0013] In an embodiment, the battery pack can be connected to an LED PCB support board with a pair of battery terminals by any method known in the art. For example, one battery terminal can attach to an electrically positive point, such as a pad, on the LED PCB, such as by means of leaf spring fingers and to the positive terminal of the battery pack with a coil spring. The second clip can be attached in a similar fashion to the LED PCB and negative terminal of the battery pack. These leaf spring fingers of the positive and negative electrical terminals can be constructed to apply pressure to the conductive pads on the LED PCB to provide firm electrical contact. The spring fingers of the terminals provide the advantage of maintaining electrical contact between the battery pack and the light source during impacts by flexing and bending.

[0014] The work light can be a handheld device, carried and held in many different positions to illuminate a work area. Preferably, the work light can be comfortably held for long periods of time. The work light handle portion is preferably adapted so that, when held, the hand is in a natural position that minimizes stress and fatigue on the muscles and joint of the hand and wrist. A handle with proper contouring and positioning for the hand requires minimal strength to hold and will be preferred by an end user over a poor handle shape that requires additional strength to grip and maintain the light in the desired orientation. Thus, the present inventive work lights minimize fatigue; and increase the length of time the light can be held.

[0015] To this end, in an embodiment, the work light provides a handle portion for gripping and retaining the work light. The handle portion of the work light can be contoured to the shape of a human hand and can contain a grip portion. The grip portion can be contoured to have a geometry that generally fits the natural dimension and spacing of the fingers of the hand. The grip portion of the handle can have one, or more preferably, an array of concave, curved indentations wrapping around the light emitting side of the light. These contours can be arranged along the handle and can have, in an embodiment, at least one indent location for each finger of a hand. The finger indentations would provide a surface upon which the fingers can rest and securely hold the work light. The circumference of the work light at the grip portion can be of a common size to fit most hands. The handle portion of the work light can be tapered from its bottom, increasing in circumference towards the light source. Tapering better accommodates the different finger lengths of a hand. The smallest indentation circumference of the work light can correspond to the small finger progressively increasing for each finger to the index finger indentation. This taper provides an improved natural grip for the fingers and palm of a hand and is preferred.

[0016] The work light handle also can be configured to provide a comfortable wrist position that prevents fatigue when holding the light. The work light can be provided with an inclined angle between the handle portion and the light source portion. In this embodiment, the inclined angle directs the light source at the work area while maintaining a natural wrist and hand position. The work light can be held in a vertical orientation while directing the illumination of the work light towards the work area in front of the handle and hand. In an embodiment, the angle of inclination of the present embodiment can be in the range of about 5 to about 15 degrees from straight, more preferably the angle of inclination is from about 6 to about 10 degrees, and more preferably the angle of inclination is about 8 degrees from vertical. This angle targets the illumination in front of the handle portion at approximately 18 inches, to provide illumination to the work area.

[0017] The power source, which in an embodiment can be a battery power source, is typically the component with the largest mass. The power source can be located inside the hollow body of the work light, at the handle portion. By locating the power source in the handle portion, the center of gravity of the work light can be located in the handle portion, just above the index finger area of the grip. In this configuration the work light, when held, is balanced above the index finger of the hand. By balancing the light in this manner, the light can be easily oriented with minimal pressure and strain to the wrist muscles and joints.

[0018] Due to the rugged environments that these work lights are found, components may occasionally be damaged from an impact or shock and may need to be replaced. Serviceability of the work light and its components helps in the repair of a damaged light and helps to maintain the light in a functional state. Therefore, the components can be and preferably are constructed in a manner for simple replacement. In an embodiment, the work light housing can have a top cap and a bottom cap which can be detached, such as by removing one or more mechanical fasteners, hi an embodiment, removal of the top cap on the hollow body can provide access to the light support panel, the electronic control panel, the moveable hook and the replaceable lens, when present, for service or replacement. In an embodiment, the bottom cap can be removed to provide access to the battery pack for service or replacement. Preferably, each component in the light is independent and can be replaced on its own or as a group as needed to return the work light to an operational state.

[0019] Certain advantages accompany the embodiment in which the leaf spring finger connectors of the battery terminals are placed within the hollow body. For instance this configuration provides a simple method for replacing or servicing the internal components of the light. The flexible properties of the battery terminal spring fingers permit the light source, which can be a LED PCB, to be removed and replaced. The spring finger of the battery terminals flex as the light source is inserted, thereby establishing a firm electrical connection to the battery pack. When the light source is inserted into the hollow body, slots which can be located in the hollow body can guide the light source to the correct position on the battery terminal spring finger for dependable operation. Similarly, the battery pack can also be guided into the hollow body by locating features that orient the battery pack in the proper position within the housing.

[0020] The use of independently serviceable components, facilitates efficient repair to the work light on location and reduces the cost and time required, as compared to the more involved method of returning the work light to a factory for repair. No transportation costs are incurred and the time required to send the light to the factory is eliminated. Using the work light of the present invention, an owner can complete a repair in minutes if a supply of replacement parts is available. In addition, the cost of a repair or service can be minimized by minimizing replacement to just the damaged component(s). To aid in this method of repair, the light source LED PCB and electronic control PCB can be separated into two unique components. The known connector devices located on both the LED PCB and electronic control PCB permit these two components to be separated and re-assembled in a predicable method that provides for dependable operation. The LED PCB and the electronic control PCB can be adapted for joining together in a defined unique interlocking manner. If one of these components sustains damage and requires replacement, the LED PCB and electronic control PCB assembly can be removed from the work light. The two components can be separated, and the damaged component replaced. However, the undamaged component can be re-used and the repaired assembly can be returned to the work light, thereby minimizing repair cost.

[0021] In addition to improving the serviceability of the work light, the ability to separate the light source LED PCB from the electronic control PCB also can be used to easily change configurations of the work light with interchangeable components that all utilize the unique interlocking feature. For example, the light source LED PCB and electronic control PCB can be provided in various configurations having the interlocking feature in common so that different work light models having distinct components can be offered. These different models can employ a common set of parts, such as housing parts, battery pack, battery terminal contacts and housings. Alternate configurations can be generated with alternative components that can be substituted into a device to provide different features, as desired. For example, the LED PCB may have alternate configurations for a very focused illumination of the work area for working in confined locations or a wide illumination of a work area to provide a flood light-type application. The different configurations of the LED PCB entail using different types of LED emitters or combination of LED emitters. Alternatively, a light source LED PCB with fewer LEDs can be offered in a lower cost work light. Alternate component configurations having the same interface features to allow exchangeability. For example all the configurations of the LED PCB preferably will have the same physical dimension to fit the body of the light in the correct orientation.

[0022] The work lights have switches for activating and deactivating the light source. Any suitable switch, of which many are known, can be used. In a preferred embodiment, activation and deactivation of the work light is accomplished using an optical switch. The optical switch is preferred because it has no moving electrical contacts as compared to commonly available mechanical switches such as toggle, rocker or push button switches. The contacts in mechanical switches are subject to factors that limit their operational life. For example, metal contacts inside mechanical switches can be broken or bent after an impact, suffer from fatigue and wear during the movement due to friction, become coated with dust or particles from the switch itself that can obstruct the mechanical parts of the switch from making the necessary electrical contact; and they are susceptible to corrosion which also impedes proper electrical contact.

[0023] The optical switch has no electrically conductive contacts. The optical switch can be constructed, on the electronic control PCB panel, with an infrared (IR) transmitter and an infrared receiver. In such an embodiment, an infrared beam is emitted from the IR transmitter and received at the IR receiver. Passing a mechanical plunger between the transmitter and receiver disrupts the IR beam. The disruption in the received beam is detected by a microprocessor which then performs the desired task of energizing or deenergizing the LEDs.

[0024] Work lights are used in a wide variety of industries such as automotive, industrial, service repair and the like. Each industry may require different lighting to best illuminate the work area from a wide flood illumination for large work areas to a small spot illumination for small confined areas. Currently LED emitters are made with pre-defined view angles of emitted light. Employing an array of LEDs with two or more different view angles in a desired pattern can provide a method for different focused illumination for the various lighting applications. For example, in a preferred embodiment, an array of 30 LEDs arranged in 3 columns of 10 LEDs, where the middle column has a different light illumination angle than the two columns on either side gives an illumination with a more intense focused beam in the center of the illumination.

[0025] In a preferred embodiment the light source is an LED light source and requires minimal amounts of electrical power to function, hi such a work light common batteries can be used as an energy source. The battery pack can be rechargeable such that it can be reenergized after use. To this end, a recharging contact can be located on the handle portion of the hollow body for each battery terminal. Each recharging contact can be connected to the battery terminal by a conductive wire. The recharging contacts can be located on the inside of the hollow body, passing through openings in the hollow body and protruding beyond the hollow body on the exterior.

[0026] In an embodiment, the light can be adapted to fit into a retaining cavity in a battery recharging stand. The stand can be adapted to make the necessary electrical contacts to recharge the battery pack when the work light is resting in the stand, such that the recharging contacts on the work light press onto the charging terminals in the stand thereby completing an electrical circuit that recharges the batteries.

[0027] In an embodiment the recharging contacts of both the work light and the charging stand are oriented in a vertical orientation. This ensures that the surface contact between the work light and charging terminals is maximized, thus making a good quality electrical contact. In an embodiment the charging terminals are located up above the bottom surface of both the work light and cavity of the charging stand respectively. This positions the charging terminals in a position away from dirt, oil, grease and other contaminates that may collect in the cavity. In an embodiment the charging stand defines a drain hole through which spilled liquids and other materials can drain. The recharging of the batteries can be greatly affected if a proper electrical connection cannot be achieved. Thus, embodiments in which the charging contacts are located away from surfaces that can collect and retain contamination are preferred such that the work light will have proper electrical circuit for recharging the batteries.

[0028] In an embodiment, the work light has multiple stable and predictable support surfaces in the hollow body. These support surfaces offer differently orientated resting positions that can be selected to provide the best direction for illuminating a work area. By providing many support surfaces the service technician can select the desired support surface that best illuminates the work area. For example, in an automotive application while working on the topside of the engine, the light could stand on its bottom cap, for example on a car battery illuminating the engine. Alternatively, for working under the car, the work light could be positioned on the ground with the light focused upward on the vehicle.

[0029] In an embodiment, the light can be equipped with a supplemental torchlight. In an embodiment, the torchlight can be positioned in the top cap. The light source for the torchlight can be a plurality of LEDs. These LEDs, like the main light source of the work light, can be varied, depending upon the type of light required. The LEDs in the torchlight source can be mounted to a PCB that fits within the cap, and can be secured with known mechanical fasteners. The torchlight can be linked to the electronic control board by wires using known connectors. The electronic control board can be configured such that it can detect torchlight attachment and can illuminate the light after the proper signal is provided by the switch. The microcontroller can adjust the operational sequence of the switch to include the torchlight into the switch sequence.

[0030] Additional features and advantages of the present invention are described in, and will be apparent from, the following Detailed Description of the Invention and the figures.

BRIEF DESCRIPTION OF THE FIGURES

[0031] Figure 1 illustrates an isometric view of an embodiment of the work light of the invention.

[0032] Figure 2 illustrates an exploded isometric view of an embodiment of the work light.

[0033] Figure 3 illustrates vertical section of the work light showing the internal components.

[0034] Figure 4 illustrates a side view of an embodiment of the work light.

[0035] Figure 5 illustrates an isometric view of an embodiment of the hollow body component of the work light.

[0036] Figure 6 illustrates an isometric view of an embodiment of a suitable light source in the invention.

[0037] Figure 7 is a rear isometric view of the light source illustrating the electronic control printed circuit boards.

[0038] Figure 8 is an exploded isometric view of an embodiment of the light source and electronic control printed circuit boards.

[0039] Figure 9 is an isometric view of an embodiment of a suitable charging system of the invention.

[0040] Figure 10 illustrates an embodiment of an LED array pattern of the invention. [0041] Figure 11 illustrates an example of suitable view angles for LEDs in the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0042] Referring to the drawings, the present invention will be seen to relate to the serviceability, durability and illumination focus of a portable work light 1, illustrated in Figure 1, used by service technicians and other persons requiring a portable temporary light.

[0043] As illustrated best in the embodiment of Figure 2, work light 1 is constructed with a hollow body 5. The hollow body can have an oval cross section and openings at each end. Hollow body 5 provides a support structure for internal components of the work light. A removable top cap 9 can cover the top opening 2 of hollow body 5. Similarly a removable bottom cap 10 can cover a bottom opening of hollow body 5.

[0044] As illustrated in Figures 2 and 3, a handle portion 3 of hollow body 5 provides a comfortable handgrip portion. A light source 20 is located within hollow body 5. In an embodiment, the work light can have a window opening 12 centered across from the light source 20 on hollow body 5. A power source 28 is mechanically and electrically connected to light source 20 within the hollow body 5 by an electrical system that includes battery contacts 3OA and 32A in electrical contact with a printed circuit board 23. In embodiments containing window opening 12, a removable light transmissive lens 8 can cover window opening 12. In an embodiment, the hollow body 5 contains a movable, ratchetable hook 11 which can be located opposite the direction of the light path, centered across from the light source 20, on the exterior of hollow body 5.

[0045] In an embodiment, hollow body 5 is constructed with a front shell 3 and a rear shell 4 of a resilient material, such as plastic. The shells can be encased in a flexible sleeve 50 of an elastomeric material. The front half 3 and rear half 4 shells can be aligned to each other by any suitable method. In one method pins 6 located on the front shell 3 can be aligned with holes 7 on the rear shell 4. This alignment method provides for accurate alignment and ensures the proper function of the hollow body 5 to retain the internal components of the light in their proper orientation. The flexible sleeve 50 provides protection by absorbing some of the energy from an impact and provides resistance to corrosive chemicals that the work light may come in contact with, hi an embodiment, the hollow body can have two non-parallel principle longitudinal axes X-Y and Y-Z, as illustrated in figure 4. In an embodiment, these two axes are the assembly directions for the serviceable components of the work light.

[0046] In an embodiment, removable top cap 9 is retained on hollow body 5 by one or more mechanical fastening screws. When attached, removable top cap 9 can be used to retain the ratchetable hook 11, the remove lens 8 and the light source 20 in place with respect to housing 5. The ratchetable hook 11, is assembled through the upper opening 2 in the hollow body 5, located in a socket 60 on the interior of the hollow body 5 and retained by rib 9B on the top cap. This rib applies a compression force to the ball of the hook to hold the proper position.

[0047] In the illustrated embodiment removable lens 8 has one or more hooks 8A, located at the lower edge of the window on the interior side, to grip and apply pressure to the lower edge of the window 12 on the hollow body 5. A hook feature 8B is also used on the removable lens 8 at the top, sufficiently low enough from the top edge to fit within the window 12 of the hollow body 5. A rib feature 9 A on cap 9 retains upper hook 8B of the removable lens 8, preventing its removal. The rib feature 9A of the top cap 9 traps the upper hook of the removable lens 8 between the interior surfaces of the hollow body 5 and the removable lens 8.

[0048] In an embodiment, ratchetable hook 11 can be stored in a cavity 13 on the exterior of the hollow body 5. Ratchetable hook 11 can be moved from a storage position to a hanging position. The ratchetable hook 11 in the hanging position is capable of supporting work light 1. The ratchetable hook can be rotated relative to the work light to orient the work light to provide illumination of the targeted work surface. The ratchetable hook 11 is made of a resilient flexible plastic material such that the material is sufficient to hold the work light 1 in place. Many such materials are known in the art and can be used. The material allows the hook to bend from its normal shape when an excessive pulling force is applied. Once the force is removed, the hook returns to its normal shape and profile.

[0049] Light source 20 for the work light 1 is an assembly of two distinct print circuit boards (PCBs) assemblies; mechanically and electrically joined by a plurality of known connectors 27. As illustrated best in Figures 6, LED PCB 21 can contain an array of LEDs 22 arranged in a suitable pattern on one side of the LED PCB. Any suitable LED pattern can be used. As best illustrated in Figure 7, an electronic control PCB 23 can be located substantially parallel to the LED PCB 21, on the side opposing the LEDs. The electronic control PCB 23 can contain an electronic microcontroller 24, an infrared (IR) transmitter 25, an IR receiver 26 and an array of current limiting circuits to properly power the LEDs at their proper illumination. Microcontroller 24 can be configured such that it energizes the LEDs when it detects a change of state in an infrared beam emitted from the IR transmitter 25 to the IR receiver 26.

[0050] In the embodiment illustrated in Figure 2, a mechanical plunger 14, composed of a button top 14A, a mechanical spring 14B, and a button shaft 14C, located on the rear half shell 4. When the button top 14A is depressed the button shaft 14C interrupts the IR beam signaling the microcontroller to switch the LED between the "on" and "off states. The plunger 14 is retracted by a mechanical spring 14B to the plunger's resting position.

[0051] Preferably, light source 20 can be assembled in the work light through opening 2 at the top of the hollow body 5. In the embodiment illustrated in Figure 5, the light source can be retained in position with a series of guide ribs 15 located on both the front half 3 and rear half 4 skeletons.

[0052] The power source of work light 1 can be a battery 28 or more preferably an array of rechargeable battery cells, electrically connected together forming a single battery pack 28. As illustrated in the embodiment of Figure 9, battery pack 28 can be removed or reinserted into the light housing through the lower opening in the hollow body 5. The battery pack contacts the negative 3OB and positive 32B battery springs on the charge device 29. The negative 30 and positive 32 terminals can convey electrical energy to and from the battery pack 28 and the light source 20. Also Figure 9 illustrates a charging circuit 29 which permits recharging the battery pack from an exterior source using a negative 31 and a positive 33 contact. These contacts can transmit electrical energy from an exterior source, through the hollow body 5 to both the battery pack 28 and light source 20 by, an electrically conductive wire 34. Electrical energy is conveyed from the negative 32A and positive 32A leaf spring finger contacts from the battery terminals to the LED PCB 21, by contact with the negative 35 and positive 36 electrically conductive pads of LED PCB 21. The negative 32A and positive 32A leaf spring finger are configured to maintain electrical contact in the event of a shock or impact. In the illustrated embodiment, the negative 32A and positive 32A leaf spring finger contacts are configured to allow the light source to be removed and replaced in the event of damage or failure.

[0053] To make the work light adaptable to the varied environment, the work light incorporates many stable and predictable resting positions. These resting positions permit the optimal position for illuminating the work area to be used. As best understood by reference to Figure 4, the work light can illuminate a work area in a horizontal plane by resting the light on the flat surface 37 of the top cap. Also the work light can illuminate along a horizontal surface by resting on the faceted surface 39. The work light can also project light upwards by positioning the work light on rectilinear surface 38 of the opposite the handle grip area.

[0054] Although the preceding description contains significant detail, it should not be construed as limiting the scope or preceding invention but rather as an illustration of the preferred embodiment of the present invention.

EXAMPLE

In this example LED PCBs were used to evaluate the effectiveness of the using different LED's view angles for light intensity within the illumination. It would be advantageous to offer different illumination patterns of the work light to specific market segment.

[0055] Employing the LED PCB array in a preferred pattern, the follow testing procedure was completed in order to test the operation of unique viewing angles and multiple view angles of the light emitting diodes and their effect on light intensity.

[0056] An LED PCB array was arranged to project light onto a targeted surface plane at a distance of 16 inches from the light, simulating a normal distance that the work light would be used. The targeted surface was located parallel to the LED PCB. A rectangular grid was placed on the targeted surface having 5 rows and 5 columns of 3" Squares. The LED PCB was centered both vertically and horizontally over this rectangular illumination grid on the targeted surface. Two sample LED arrays were used. The first test array had a view angle of 50 degrees arranged in a pattern of 3 columns of 10 LEDs each, as shown in Figure 10. The second test array employed the same pattern of 3 columns of 10 LEDs, wherein the middle column (Y) shown in Figure 10 had LEDs having a view angle of 18 degrees and the outer columns (X) and (Z) had a viewing angle of 50 degrees as in the first test array.

[0057] Light intensity of each grid square was recorded. Three trial runs were done, and the intensities for each grid square were averaged to provide a result. In order to compare the values between the two different samples, a ratio was used by determing the lowest illumination value and comparing each of the other values to it. This ratio is used to compare the two test arrays.

[0058] Table 1 and 2 shows the test measurements of the average relative intensities from each test sample. Table 1 provides the average relative intensities obtained from the grid by illumination with test array 1. Table 2 provides the average relative intensities obtained from the grid by illumination with test array 2.

Table 1

Table 2

[0059] The results show that the illumination of the second test sample with the narrower view angle LEDs in the middle column (Y) has a greater relative illumination intensity on the test grid in column 3 between squares B, C and D. This correlation between the narrower view angle and the illumination intensity in the middle of the test grid shows that employing LEDs with narrower viewing angles results in a more focused illumination area.

[0060] Moreover, the above test results indicate that a work light with an array of LED with different view angles can be effectively offered to the market to provide a work light with a narrow illumination area. Narrow focus work lights may be advantageous for repair work in small and limited areas where a smaller focused illumination beam is needed. Similarly, a wide focus work light with LEDs with a wide viewing angle is advantageous for illuminating an area that overall illumination is preferred.

[0061] It should be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present invention and without diminishing its intended advantages. It is therefore intended that such changes and modifications be covered by the appended claims.

[0062] It should be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present subject matter and without diminishing its intended advantages. It is therefore intended that such changes and modifications be covered by the appended claims.

Claims

CLAIMSThe invention is claimed as follows:

1. A work light comprising a handle portion comprising a grip contoured to the shape of a human hand and having spacings for the fingers of the hand.

2. The work light of Claim 1, wherein the finger spacings comprise a concave curved indentation wrapping around the light emitting side of the lamp.

3. The work light of Claim 1, wherein the finger spacings comprise an array of concave curved indentations wrapping around the light emitting side of the lamp wherein at least one indentation is present for each finger of a typical hand.

4. The work light of Claim 1 , wherein the handle portion of the work light is tapered from its bottom and increases in circumference towards the light source.

5. A work light comprising a housing having a bend that separates a light emitting portion from a handle portion.

6. The work light of Claim 5, wherein the bend has an angle in the range of about 5 to about 15 degrees from straight.

7. The work light of Claim 5, wherein the housing is composed of two joined portions each comprising a handle portion.

8. The work light of Claim 5, wherein a battery powered energy source is substantially completely located in the handle portion.

9. The work light of Claim 5, wherein a light source is located substantially completely in the light emitting portion.

10. The work light of Claim 5, wherein the center of gravity is within the handle portion.

11. The work light of Claim 5, wherein the work light is activated and deactivated using an optical switch.

12. The work light of Claim 5, further comprising a light source PCB and an electronic control PCB forming an interface within electrical contact for operating the light source.

13. The work light of Claim 5, further comprising a light source PCB and an electronic control PCB having an interlocking interface adapted to provide electrical contact for operating the light source, wherein the light source and electronic control PCBs can be detached and attached to each other through the interface.

14. The work light of Claim 5, further comprising any one of a variety of light source PCBs having a common interlocking interface, and any one of a variety of electronic control PCBs having a common interlocking interface adapted to provide electrical contact for operating the light source, wherein any of the variety of light source PCBs and electronic control PCBs can be detached and attached in a common manner through the common interlocking interface.

15. The work light of Claim 5, further comprising a lens component that can be replaced independently of other parts of the light.

16. The work light of Claim 5, further comprising light source PCB and electronic control PCB having an interface adapted to provide electrical contact for operating the light source, and wherein the electronic control PCB panel further comprises an optical switch.

17. The work light of Claim 5, further comprising light source PCB and electronic control PCB having an interface adapted to provide electrical contact for operating the light source, and wherein the electronic control PCB panel further comprises an optical switch which switches in response to an interruption in the passage of light between a light emitter and a light receiver.

18. The work light of Claim 5, further comprising a recharging contact in electrical contact with a battery terminal and extending from within the housing to the exterior of the housing.

19. The work light of Claim 5, further comprising a recharging contact in electrical contact with a battery terminal and extending from within the housing to the exterior of the housing wherein the portion of the contact on the exterior of the housing is adapted to electrically connect with recharging terminals in a recharging device.

20. The work light of Claim 5, further comprising a recharging contact in electrical contact with a battery terminal and extending from within the housing to the exterior of the housing wherein the portion of the contact on the exterior of the housing is adapted to electrically connect with a recharging terminal in a retaining cavity of a battery recharging stand.

21. The work light of Claim 5, further comprising a torchlight.

22. The work light of Claim 5, further comprising a torchlight wherein the torchlight is located in a top cap which covers the housing.