Watertight, low power L.E.D. flashlight

• US 6,793,366 B2
• Filed: 03/22/2002
• Issued: 09/21/2004
• Est. Priority Date: 03/22/2002
• Status: Active Grant

• Current Assignee: James K. Chun
• Original Assignee: James K. Chun
• Inventors: Chun, James K.
• Primary Examiner(s): Cariaso, Alan
• Assistant Examiner(s): Alavi, Ali
• Application Number:
  US10/104,895
• Publication Number:
  US 20030179573A1
• Time in Patent Office: 914 Days
• Field of Search: 362/200, 362/205, 362/157-158, 362/183, 362/190, 362/184, 362/116, 362/396, 362/800, 362/267, 362/186, 315/241-242, 315/224-225, 315/307
• US Class Current: 362/184
• CPC Class Codes: F21L 4/027 the light sources being a LED
• CPC Class Codes: F21V 15/01 Housings, e.g. material or assembling of housing parts F21V15/02 takes precedence housings forming signs or letters G09F13/04
• CPC Class Codes: F21V 31/005 Sealing arrangements therefor
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H05B 45/38 using boost topology
• CPC Class Codes: Y02B 20/30 Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

Abstract

A watertight, low power flashlight is disclosed that uses a voltage tripler and regulator that enables the use of a single AA or lithium battery. The voltage tripler is a “step-up power component” that raises the battery voltage from 1.5 volts to approximately 5 volts required to sufficiently energize the L.E.D.s. The flashlight also includes a lightweight, compact housing with an optional dimmer switch and a side-mounted on/off switch.

Claims

1. A flashlight comprising,

a. a flashlight housing adapted to hold a battery;

b. at least one L.E.D. located in said housing;

c. a voltage multiplier circuit coupled between said L.E.D and the battery when the battery is disposed in said housing, said voltage multiplier circuit includes a digital synchronous boost converter that provides an output voltage greater than the input voltage from the battery and synchronizes the input voltage and the output voltage so that the output voltage is maintained as the input voltage decreases; and

,

d. an ON-OFF switch connected to said voltage multiplier circuit.

2. The flashlight as recited in claim 1, further including a dimmer switch connected to said voltage multiplier circuit.

3. The flashlight as recited in claim 1, wherein said synchronous boost converter is capable of supplying 3.3 volts at 150 MA.

4. The flashlight as recited in claim 1, wherein said battery supplies 1.5 Volts.

5. The flashlight as recited in claim 1, wherein said flashlight includes two L.E.D.s.

6. The flashlight as recited in claim 1, further including a key ring attached to said housing.

7. The flashlight as recited in claim 1, further including a belt clip attached to said housing.

8. The flashlight as recited in claim 1, further including a reflector located inside said lens and disposed around said L.E.D.

9. The flashlight as recited in claim 1, wherein said housing is watertight.

10. The flashlight as recited in claim 1, further including a belt clip attached to said housing.