LED flashlight with improved heatsink

• US 9,494,308 B1
• Filed: 06/14/2016
• Issued: 11/15/2016
• Est. Priority Date: 12/22/2014
• Status: Active Grant

• Current Assignee: MAG Instrument Incorporated
• Original Assignee: MAG Instrument Incorporated
• Inventors: Maglica, Anthony
• Primary Examiner(s): Ton, Anabel
• Application Number:
  US15/182,396
• Publication Number:
  US 20160356480A1
• Time in Patent Office: 154 Days
• US Class Current: 1/1
• CPC Class Codes: F21L 4/005 the device being a pocket lamp F21L4/022, F21L4/045, F21L4/085 take precedence
• CPC Class Codes: F21L 4/027 the light sources being a LED
• CPC Class Codes: F21L 4/085 Pocket lamps
• CPC Class Codes: F21V 15/04 Resilient mountings, e.g. shock absorbers shock absorbing devices of vehicle headlamp housings B60Q1/0491; in general F16F15/04
• CPC Class Codes: F21V 17/101 permanently, e.g. welding, gluing or riveting
• CPC Class Codes: F21V 17/12 by screwing
• CPC Class Codes: F21V 19/005 by permanent fixing means, e.g. gluing, riveting or embedding in a potting compound
• CPC Class Codes: F21V 23/0428 the switch being part of, or disposed on the lamp head portion thereof
• CPC Class Codes: F21V 23/06 the elements being coupling devices , e.g. connectors
• CPC Class Codes: F21V 29/503 of light sources cooling arrangements structurally associated with gas-discharge or vapour-discharge lamps H01J61/52; cooling arrangements structurally associated with electric incandescent lamps H01K1/58; cooling arrangements structurally associated with light-emitting diodes H01L33/64
• CPC Class Codes: F21V 29/70 characterised by passive heat-dissipating elements, e.g. heat-sinks
• CPC Class Codes: F21V 29/713 in direct thermal and mechanical contact of each other to form a single system
• CPC Class Codes: F21V 29/89 Metals
• CPC Class Codes: F21V 3/00 Globes; Bowls; Cover glasses with refracting properties F21V5/00; with reflecting properties F21V7/00; characterised by cooling arrangements F21V29/506
• CPC Class Codes: F21V 7/00 Reflectors for light sources characterised by cooling arrangements F21V29/505
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 33/483 Containers
• CPC Class Codes: H01L 33/62 Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls
• CPC Class Codes: H01L 33/642 : characterized by the shape
• CPC Class Codes: H01M 10/0481 : Compression means other than compression means for stacks of electrodes and separators
• CPC Class Codes: H01M 10/613 : Cooling or keeping cold
• CPC Class Codes: H01M 10/623 : Portable devices, e.g. mobile telephones, cameras or pacemakers
• CPC Class Codes: H01M 10/643 : Cylindrical cells
• CPC Class Codes: H01M 10/655 : Solid structures for heat exchange or heat conduction
• CPC Class Codes: H01M 2220/30 : Batteries in portable systems, e.g. mobile phone, laptop
• CPC Class Codes: H01M 50/213 : adapted for cells having curved cross-section, e.g. round or elliptic H01M50/209, H01M50/216 take precedence
• CPC Class Codes: H01M 50/51 : Connection only in series
• CPC Class Codes: H01M 50/516 : by welding, soldering or brazing
• CPC Class Codes: Y02E 60/10 : Energy storage using batteries
• CPC Class Codes: Y02P 70/50 : Manufacturing or production processes characterised by the final manufactured product

Abstract

One electrical lead from an LED package is soldered to an inner electrically conductive member positioned and electrically isolated from an outer electrically conductive member by electrically insulating material while a second electrical lead and a neutral lead from the LED are soldered to the outer electrically conductive member so that heat is transferred from an LED die within the LED package to the outer electrically conductive member and then to a thermally conductive outer casing with a thermal path that minimizes thermal resistance.

Claims

1. A lighting apparatus, comprising:

an outer casing that is thermally conductive;

a light emitting diode (“

LED”

) package contained within the outer casing, said LED package comprising;

a substrate;

an LED die held by the substrate, said LED die configured to emit light outwardly from a front surface of the LED package;

a first electrically conductive pad;

a second electrically conductive pad; and

a thermal pad configured for removing heat from the LED die to outside of the LED package;

wherein the first and second electrically conductive pads are configured to provide power to cause the LED die to emit light;

wherein the first and second electrically conductive pads and the thermal pad are located on a rear surface of the LED package opposite from the LED die; and

a heatsink assembly held within the outer casing, said heatsink assembly comprising;

an outer electrically conductive member that is thermally conductive and which is mechanically connected to the outer casing;

a core of an electrically insulating material which is held within a cavity formed in the outer electrically conductive member; and

an inner electrically conductive member which is positioned and electrically isolated from the outer electrically conductive member by the core;

wherein the first electrically conductive pad and the thermal pad are thermally and electrically bonded to a first top surface of the outer electrically conductive member without use of a printed circuit board and the second electrically conductive pad is electrically bonded to a second top surface of the inner electrically conductive member.

2. The lighting apparatus of claim 1, wherein the first electrically conductive pad and the thermal pad are soldered to the first top surface and the second electrically conductive pad member is soldered to the second top surface.

3. The lighting apparatus of claim 1, wherein the core and the inner electrically conductive member are comprised of a single molded assembly.

4. The lighting apparatus of claim 1, wherein the core is configured to form a passageway between the core and the outer electrically conductive member when the core is inserted into the cavity.

5. The lighting apparatus of claim 4, further comprising an epoxy held within the passageway.

6. The lighting apparatus of claim 5, further comprising a mechanical means for holding the core within the cavity.

7. The lighting apparatus of claim 5, further comprising a printed circuit board (“

PCB”

) held within the core in a vertical orientation with respect to the first top surface.

8. The lighting apparatus of claim 1, wherein the lighting apparatus is comprised of a flashlight and the outer casing is comprised of a flashlight barrel.

9. A method for creating a flashlight mode with increased lumens or with increased on-time, comprising:

inserting a core which holds an inner electrically conductive member into a cavity formed in an outer electrically conductive member so that a second top surface of the inner electrically conductive member is positioned within an opening in a first top surface of the outer electrically conductive member and the inner and outer electrically conductive members are electrically isolated from one another;

soldering both a first electrically conductive pad and a thermal pad of a light emitting diode (“

LED”

) package to the first top surface without use of a printed circuit board as well as soldering a second electrically conductive pad of the LED package to the second top surface to form a heatsink assembly, wherein said LED package is comprised of the first electrically conductive pad, the second electrically conductive pad and the thermal pad, wherein the first and second electrically conductive pads are configured to provide power to cause a die within the LED package to emit light outwardly from a front surface of the LED package, wherein the thermal pad is configured for removing heat from the LED package, and wherein the first and second electrically conductive pads and the thermal pad are located on a rear surface of the LED package opposite from the die; and

inserting the heat sink assembly into a flashlight barrel so that the heat sink assembly is held by mechanical contact with the barrel and a thermal path is created between the flashlight barrel and the first electrically conductive pad and the thermal pad of the LED package which is only interrupted by a first thermal junction between the flashlight barrel and the outer electrically conductive member and a second thermal junction between the outer electrically conductive member and the first electrically conductive pad and the thermal pad of said each LED package;

wherein providing power to the first and the second electrically conductive pads of the LED package cause the die within the LED package to emit light.

10. The method of claim 9, further comprising the step of putting epoxy into a passageway formed between the core and the outer electrically conductive member after the core is inserted into the cavity.

11. The method of claim 10, wherein the epoxy creates a mechanical means for holding the core within the cavity.