LED accessory for vehicle and method of assembly

Abstract

A lighted accessory for a motor vehicle includes a machined aluminum body. The body includes a front wall that has a plurality of openings through it and a cavity behind it. A plurality of lenses are potted in place within the openings. LED lights are installed on the aluminum body in alignment with the lenses. Additional potting compound is applied to cover the LEDs and substantially fill the cavity. A faulty LED board may be replaced by removing a portion of the potting compound and the faulty LED board, replacing the faulty LED board with an operable one, and refilling the removed portion of the potting compound with additional potting compound.

Claims

1. A method of assembling a lighted vehicle accessory, the method comprising: providing an accessory body having a front wall, a cavity behind the front wall, an opening through the front wall, and a lens receptacle on a rear surface of the front wall surrounding the opening; placing a lens in the lens receptacle in alignment with the opening; applying a first layer of potting compound around the lens in the lens receptacle to secure the lens in place and form a watertight seal between the lens and the body; allowing the first layer of potting compound to at least partially cure; securing a circuit board that includes a light emitting diode (LED) to the rear surface of the front wall with the LED in alignment with the lens; substantially filling the cavity with a second layer of potting compound to completely cover the circuit board within the cavity; configuring the second layer of potting compound to damp vibrations in the circuit board; allowing the second layer of potting compound to at least partially cure; and securing a rear cover to the body to at least partially cover the at least partially cured second layer of potting compound.

2. The method of claim 1, further comprising machining a single piece of high density anodized aluminum to form the accessory body.

3. The method of claim 2, wherein the single piece of high density anodized aluminum is configured to act as a heat sink for the circuit board and LEDs.

4. The method of claim 1, wherein a CNC machine is used to machine the solid block of aluminum.

5. The method of claim 1, wherein the LED is a surface mount device.

6. The method of claim 1, further comprising securing attachment hardware to the body, wherein the attachment hardware is adapted to connect to a vehicle.

7. The method of claim 1, wherein the first and second layers of potting compound are high elongation epoxies.

8. The method of claim 1, wherein the second layer of potting compound is a longer working time potting compound than the first layer of potting compound.

9. The method of claim 1, wherein the first layer of potting compound is applied around the periphery of the lens within the lens receptacle.

10. The method of claim 1, wherein the first layer of potting compound has strong adhesive properties with respect to aluminum.

11. The method of claim 1, further comprising regulating operation of the LEDs with thermal control chips of the circuit board.

12. The method of claim 1, wherein the opening is machined at a right angle to a front wall, causing the lens to be oriented normally with respect to the front wall.

13. The method of claim 1, wherein the distance between the front wall and the back cover may be no less than three fourths of an inch and no more than one and a half inches.

14. The method of claim 1, wherein the opening is machined at an oblique angle relative to the front wall, causing light to be directed into the lens in a direction other than a right angle with respect to the front wall.

15. A method of repairing a lighted vehicle accessory that includes a plurality of circuit boards wherein one of the circuit boards is faulty, the method comprising: taking a lighted vehicle accessory and determining that at least one of its LED lights is non-functioning; identifying a circuit board within the accessory that corresponds with at least one non-functioning LED light; removing a rear cover from the accessory; using a cutting device to cut a portion of a layer of potting compound covering the identified circuit board; peeling away the cut portion of the layer of potting compound; removing the identified circuit board; replacing the identified circuit board with a replacement circuit board; covering the replacement circuit board with a new layer of potting compound; allowing the new layer of potting compound to at least partially cure; reattaching the rear cover to the accessory after allowing the new layer of potting compound to at least partially cure.

16. The method of claim 15, further comprising: before performing the steps of claim 15, removing the accessory from a vehicle; and after performing the steps of claim 15, reconnecting the accessory to the vehicle.

17. The method of claim 15, wherein the new layer of potting compound is a high elongation epoxy.

18. The method of claim 15, further comprising configuring the new layer of potting compound to damp vibrations in the circuit board.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a front view of a motor vehicle with lighted vehicle accessories attached according to the present invention.

(2) FIG. 2 shows a lighted vehicle accessory that includes two rows of three LEDs according to one embodiment of the present invention.

(3) FIG. 3 shows a lighted vehicle accessory according to another embodiment of the present invention, wherein the accessory is an elongated LED light bar.

(4) FIG. 4 is a cross sectional view of a machined aluminum body used in the elongated light bar of FIG. 3.

(5) FIG. 5 shows the aluminum body of FIG. 4 with a lens potted into place within an opening of the front wall of the aluminum body.

(6) FIG. 6 shows the assembly of FIG. 5 with a circuit board including an LED light mounted in place on the aluminum body.

(7) FIG. 7 shows the assembly of FIG. 6 wherein the rear cavity of the aluminum body has been filled with potting adhesive.

(8) FIG. 8 is a cross sectional view of the elongated light bar of FIG. 3.

(9) FIG. 9 is a flow chart illustrating a process for assembling a lighted-vehicle accessory according to one embodiment of the present invention.

(10) FIG. 10 is a flow chart illustrating a method of assembling a lighted vehicle accessory according to one embodiment of the present invention.

(11) FIG. 11 is a flow chart of a method of repairing a lighted vehicle accessory that includes a plurality of circuit boards wherein one of the circuit boards is faulty.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

(12) FIG. 1 is a front view of a vehicle 12 that includes several lighted accessories 10. As can be seen, the lighted accessory 10 may take the form of an elongated bar mounted on the roof of the vehicle, an elongated bar mounted at vehicle grill, a light bar provided on the bumper, or as fog lights. Those skilled in the art will be aware of numerous possible locations and configurations for lighted vehicle accessories. According to the present invention, the lighted accessory 10 is an LED lighted accessory of improved construction. The lighted accessories 10 may be connected to the vehicle's electrical system. Typically, a user will be able to control illumination of the lighted accessories 10 through the existing lighting controls of the vehicle 12.

(13) FIG. 2 shows an LED lighted accessory 10 according to one embodiment of the present invention. The lighted accessory 10 includes a rectangular body 14. The front face 16 of the body 14 is visible in FIG. 2. The front face 16 of the body 14 includes a plurality of openings 18. In the embodiment of FIG. 2 there are six total openings 18 provided in two rows of three openings. Within each of the openings 18 a lens 20 is mounted, and through which light from a light source will shine. The accessory 10 also includes a wire harness 22 that is adapted to be connected into the vehicle's electrical system to provide power to the lights. The lighted accessory 10 also includes mounting holes 24 to provide for mounting the lighted accessory 10 to the vehicle 12.

(14) FIG. 3 shows another embodiment of a lighted accessory 110 according to the present invention. The lighted accessory 110 of FIG. 3 is an elongated bar that includes a single row of lights. The lighted accessory 110 of FIG. 3 also includes a body 114 preferably made from aluminum. The body 114 includes a front face 116 including a row of openings 118. Each of the openings 118 is provided with a lens 120 through which light from the LEDs shines. While not visible in FIG. 3, the lighted accessory 110 of FIG. 3 also includes a wire harness for connection to the vehicle's electrical system. Each end of the lighted accessory 110 of FIG. 3 includes mounting hardware 126, which is used to mount the light bar 110 to the vehicle, for example to mount the light bar 110 to a vehicle grill.

(15) FIG. 4 shows a cross sectional view of the body 114 of the lighted accessory 110 from FIG. 3. The body 114 is preferably made from a single piece of anodized aluminum that has been machined into a desired configuration using a CNC machine. A cavity 136 is machined into the body 114 to form the top and bottom walls 130, the front wall 128, and the side walls 134. The body 114 includes a front wall 128 and rearwardly extending top and bottom walls 130. One of the openings 118 through the front wall 128 is shown in FIG. 4. The overall thickness of the body 114 from the front face 116 to the back face of the walls 130 is preferably no more than one and one-half inches, and may be as small as three quarters of an inch. A recessed area is machined into the front wall 128 to form a lens receptacle 132. The body 114 may be formed as a generally straight flat prismatic shape, or may be curved to match a contour of the vehicle or space on the vehicle where it is intended to be mounted.

(16) FIG. 5 shows the lighted accessory body 114 of FIG. 4 at an early stage of the assembly process wherein a lens 138 has been inserted into the lens receptacle 132 in alignment with the opening 118. As shown in FIG. 5, the opening 118 is machined at a right angle to the front face 116. This standard orientation for the opening 118 causes the lens 138 to be oriented normally with respect to the front face 116, and to generally direct the light at a right angle to the front face 116. As an alternative (not shown) the opening 118 may be machined at an oblique angle relative to the front face 116 in order to direct the light in a direction other than simply a right angle from the face 116. A potting adhesive 140 is applied around the periphery of the lens 138 within the lens receptacle 132 in order to secure the lens 138 in place, and to form a watertight seal to prevent any water or other contaminants from entering the lighted accessory through the opening 118. The potting adhesive 140 may be a high elongation epoxy that is self-leveling, for example a potting compound sold under the trade name Tough Seal 21. Preferably the potting adhesive will be one that has strong adhesive properties with respect to aluminum.

(17) After the potting adhesive 140 has been allowed to dry, a circuit board 142 is installed on the body 114. The circuit board 142 includes a light emitting diode (LED) 144 that is in alignment with the lens 138. In practice the circuit board 142 may include more than one LED in alignment with more than one lens 138. The circuit board 142 may be secured to the body 114 with mechanical fasteners 145, for example threaded screws. Preferably the circuit board 142 will include the LEDs as surface mount devices in a solid state design. Those of ordinary skill in the art will be aware of numerous LED types that may be advantageously incorporated into the present invention.

(18) As seen in FIG. 7, after the circuit board 142 is installed a second layer of potting compound 146 is applied within the cavity 136 in order to substantially fill the cavity 136. The layer of potting compound 146 completely covers and protects the circuit board 142. The potting compound 146 completely protects the circuit board and lens from water and dust. Additionally, the potting compound 146 provides support and cushioning that will damp vibrations which can cause humming, and will protect the circuit board from impact stresses. The second layer of potting compound 146 may be the same or a different high elongation epoxy than is used in the potting adhesive 140 that secures the lens 138 in place. For example, the second layer of potting compound 146 may be a longer working time potting compound sold under the brand name Tough Seal 22.

(19) After the second layer of potting compound 146 is allowed to cure, a rear cover 148 may be secured to the body 114 by applying mechanical fasteners 150, which may be for example bolts or screws, to secure the rear cover 148 to the side walls 134. Mounting hardware 126 (see FIG. 3) may then be attached to the body 114 such that the lighted accessory 110 can be mounted to a vehicle.

(20) The resulting lighted accessory 110 has significant advantages over existing designs. For example, the accessory 110 is low profile such that the overall dimension between the front face 116 and the back plate 148 may be no more than one and a half inches, and may be as little as three fourths of an inch. The fully potted rear cavity assures that the accessory 110 is well suited to withstand the rigors of outdoor use as it protects the circuit board 142 and LEDs 144 from water and from mechanical stresses. The potting compound 146 will absorb and damp the vibrations that can cause humming. The high density aluminum body 114 acts as an efficient heat sink to maintain the circuit boards 142 and LEDs 144 within an acceptable temperature range. The circuit boards 142 may include thermal control chips to regulate operation of the LEDs 144 in order to extend the life of the components.

(21) If one of the circuit boards 142 should fail, it is possible to repair the lighted accessory 110. This can be accomplished by removing the back cover 148. The potting compound 146 that covers the non-functional circuit board 142 may be removed, for example by using a razor blade or other sharp instrument to slice out a portion of the potting compound 146 directly above the faulty circuit board 142. With a portion of the potting compound 146 removed, the circuit board 142 can be unscrewed from the body 114 and removed, and a new properly functioning circuit board 142 may be installed in its place. Additional potting compound may then be applied to fill in the gap within the potting compound 146 and again completely seal the new circuit board 142. After the new portion of potting compound has been allowed to completely cure, the back cover 148 may again be screwed into place, and the lighted accessory 110 may be reinstalled on the vehicle.

(22) FIG. 9 is a flow chart illustrating a process for assembling a lighted-vehicle accessory according to one embodiment of the present invention.

(23) The invention has been shown and described above with the preferred embodiments, and it is understood that many modifications, substitutions, and additions may be made which are within the intended spirit and scope of the invention. From the foregoing, it can be seen that the present invention accomplishes at least all of its stated objectives.