LED work light

• US 20050265035A1
• Filed: 03/18/2005
• Published: 12/01/2005
• Est. Priority Date: 03/18/2004
• Status: Active Grant

• Current Assignee: Alltemp Products Company Limited (DiversiTech Holdings, Inc.)
• Original Assignee: Brasscorp Limited
• Inventors: Dobbin, Sarah, Klipstein, Donald L., Brass, Jack, Hallgrimsson, Bjarki, Hilts, Lorne, Whitfield, Robert Tod
• Granted Patent: US 7,553,051 B2
• Time in Patent Office: Days
• US Class Current: 362/451
• CPC Class Codes: F21L 14/023 having two or more, or different light sources
• CPC Class Codes: F21L 4/00 Electric lighting devices with self-contained electric batteries or cells
• CPC Class Codes: F21L 4/08 characterised by means for in situ recharging of the batteries or cells
• CPC Class Codes: F21S 4/20 with light sources held by or within elongate supports
• CPC Class Codes: F21S 45/47 Passive cooling, e.g. using fins, thermal conductive elements or openings
• 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 17/12 by screwing
• CPC Class Codes: F21V 21/06 Bases for movable standing lamps; Fixing standards to the bases F21V21/08 takes precedence
• CPC Class Codes: F21V 21/08 Devices for easy attachment to any desired place, e.g. clip, clamp, magnet
• CPC Class Codes: F21V 21/32 Flexible tubes
• CPC Class Codes: F21V 21/406 for portable lighting devices
• CPC Class Codes: F21V 23/02 the elements being transformers, impedances or power supply units, e.g. a transformer with a rectifier
• CPC Class Codes: F21V 23/0435 activated by remote control means
• CPC Class Codes: F21V 27/005 for portable lighting devices
• CPC Class Codes: F21V 29/70 characterised by passive heat-dissipating elements, e.g. heat-sinks
• CPC Class Codes: F21V 29/75 with fins or blades having different shapes, thicknesses or spacing
• CPC Class Codes: F21V 29/763 the planes containing the fins or blades having the direction of the light emitting axis
• CPC Class Codes: F21V 29/83 the elements having apertures, ducts or channels, e.g. heat radiation holes
• CPC Class Codes: F21V 5/04 of lens shape
• CPC Class Codes: F21V 7/0091 using total internal reflection
• CPC Class Codes: F21Y 2103/10 : comprising a linear array of point-like light-generating elements
• CPC Class Codes: F21Y 2115/10 : Light-emitting diodes [LED]
• CPC Class Codes: H05B 45/10 : Controlling the intensity of the light
• CPC Class Codes: H05B 45/375 : using buck topology
• CPC Class Codes: H05B 45/38 : using boost topology
• CPC Class Codes: H05B 45/56 : involving measures to prevent abnormal temperature of the LEDs
• CPC Class Codes: Y02B 20/30 : Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

Abstract

Work light has LEDs that require heatsink. Desired radiation pattern achieved by using optical components designed to produce beam or LEDs may have beams in different directions. Radiation pattern of LEDs may be changed by refractive-reflective optics or by convex lenses. Convex lenses may be hemispheres, other planoconvex shapes, concavo-convex shapes, or other shapes. Curved surfaces on any lenses may be spherical or aspheric. Ballast to operate the LEDs from line voltage AC or low voltage DC. Work light may contain batteries. The work light may be mounted on a stand. May have accessory mount. May have charging station. May have a paging transmitter to activate a paging receiver in work light. May have openings for heat transfer from heatsink to ambient air external to light.

Claims

1. An LED work light comprising:

a) a light head,

b) at least one light emitting diode (LED) contained within the light head, and

c) a handle that is attached to said light head,

wherein the light head emits light external to the light head from light emitted by the at least one LED,

wherein the at least one LED is of a high power type that normally requires heatsinking, and

wherein the light emitted from the work light is in the form of a beam that has a useful beam width of light adequate for use in working for prolonged periods is essentially at least 40 degrees wide and essentially no more than 90 degrees wide.

5. The LED work light of claim 1 wherein the LEDs are white LEDs.

6. The LED work light of claim 1 further comprising one or more heatsink that assist in dissipating heat from any of the light emitting diodes.

7. The LED work light of claim 1 wherein one or more optical components are included in order to achieve a beam width of at least 40 degrees and no more than 90 degrees.

8. The LED work light of claim 7 wherein at least one of the optical pieces is a molded plastic part wherein total internal reflection occurs.

9. The LED work light of claim 1 wherein each light emitting diode of the at least one light emitting diode produces a beam less than 40 degrees wide and the at least one light emitting diode is arranged to produce a combined beam that is at least 40 degrees wide.

10. The LED work light of claim 1 wherein the at least one light emitting diode produces a beam that is more than 90 degrees wide and further comprising one optical component for each light emitting diode of the at least one light emitting diode, each optical component is placed forward from its respective light emitting diode in order for said work light to produce a beam that is essentially less than 90 degrees wide.

11. The LED work light of claim 10 wherein at least one optical component is a prism.

12. The LED work light of claim 6 where said LED work light is also able to work from low voltage direct current.

13. The LED work light of claim 12 further comprising a cavity for receiving a removable DC power source.

14. The LED work light of claim 1 wherein the light head has a casing that is plastic.

15. The LED work light of claim 1 further comprising one or more pieces of compressible material to protect the work light from impacts.

16. The LED work light of claim 15 wherein the impact protection material is selected from rubber or a thermoplastic elastomer.

17. The LED work light of claim 10 wherein each optical component is a convex lens.

18. The work light of claim 17 wherein the convex lenses are part of a transparent lens assembly.

19. The work light of claim 18 wherein the transparent lens assembly is molded.

20. The work light of claim 19 wherein the lens assembly is machined after molding.

21. The work light of claim 20 wherein the lens assembly is polished after machining.

22. The LED light of claim 17 wherein each convex lens is planoconvex.

23. The LED light of claim 22 wherein each planoconvex lens is aspheric.

24. The LED work light of claim 13 wherein the removable DC power source comprises rechargeable batteries.

25. The LED work light of claim 13 wherein the removable DC power source is an external power source with wire conductors.

26. The LED work light of claim 13 where the LED work light is operated from essentially 12 or 12-14 volts DC.

27. A kit comprising the work light of claim 13 and a first removable DC power source comprising rechargeable batteries and a second removable DC power source, comprising an external power source with conductors for connection in the cavity, wherein the first removable DC power source and second removable DC power source are interchangeable in the cavity.

28. The kit of claim 27 further comprising a charging base that can recharge the batteries.

29. The kit of claim 27 wherein the second removable DC power source further comprising an AC line voltage to low voltage DC transformer and a line voltage cord, the transformer between the conductors for electrical connection to the cavity and the line voltage cord.

30. The LED work light of claim 1 further comprising a paging receiver.

31. The LED work light of claim 30 wherein the paging receiver can be used for locating the work light.

32. The LED work light of claim 1 further comprising a paging receiver and an alarm that when activated, assists in locating the work light wherein the paging receiver receives pages from an external device, wherein the work light causes the alarm to activate upon receipt of a page by the paging receiver from the external device.

33. The LED work light of claim 32 wherein the alarm comprises activation of the light.

34. The kit of claim 28 wherein the LED work light further comprises a paging receiver and the charging base comprises a transmitter for transmitting pages to the paging receiver.

66. The work light of claim 1 further comprising an accessory mount for receiving a work light accessory.

67. The work light claim 66 wherein the work light accessory is a work light mounting device.

68. The work light of claim 67 wherein the work light mounting device is a stand for mounting the work light on top of a generally horizontal surface.

69. The work light of claim 68 wherein the work light mounting device is a mounting bracket for mounting the work light to an external location.

71. The work light of claim 5 further comprising an elongate handle operatively connected to the head section, wherein the handle extends away from the head section outside a volume bounded by the width and height of the head section such that the handle does not increase the depth of the work light in that volume.

72. The work light of claim 5 further comprising an elongate handle having a longitudinal axis, wherein the handle is operatively connected to the head section, wherein the longitudinal axis that extends through the head section in a direction generally perpendicular to the beam axis.

73. The work light of claim 1 further comprising a generally cylindrical handle that extends from the head section generally perpendicular to the central beam axis.

74. The work light of claim 7 wherein the handle has a diameter that is less than the width of the head section.

75. The work light of claim 8 wherein the depth of the head section is less than the diameter of the handle.

78. The LED work light of claim 10, wherein the at least one light emitting diode nominally has a lambertian radiation pattern.

79. The LED work light of claim 17, wherein the at least one light emitting diode nominally has a lambertian radiation pattern.

81. The LED work light of claim 17 wherein at least one convex lens has both a convex surface and a concave surface.

82. The LED work light of claim 81 wherein the convex surface has a diameter and the concave surface has a diameter smaller than that of the convex surface.

83. The LED work light of claim 81 where the concave surface is curved more sharply towards its edge than towards its center.

84. The LED work light of claim 83 wherein the concave surface is flat in its center.

2. A work light comprising:

a) a high power LED that requires a heatsink for operation in a normal working environment while preserving a useful life in prolonged use,

b) an optic associated with the LED such that a beam width of light radiating from the LED is changed by the optic, and light emitting from the optic has a useful beam width of light adequate for use in working for prolonged periods,

c) a heatsink for use with the LED to preserve useful working life of the LED when operated in prolonged use,

d) a casing substantially enclosing the LED and optic, and the casing housing the heatsink, and

e) a transparent cover in the casing through which the beam of light from the optic can escape the casing along a beam axis.

3. A work light comprising:

a) a high power LED that requires a heatsink for operation in a normal working environment while preserving a useful life in prolonged use,

b) an optic associated with the LED such that the optic creates a beam emitting from the optic for use in working for prolonged periods that has a more uniform light density across its beam width than the light density across a beam emitted by the LED,

c) a heatsink for use with the LED to preserve useful working life of the LED when operated in prolonged use,

d) a casing substantially enclosing the LED and optic, and housing the heatsink, and

e) a transparent cover in the casing through which the beam of light from the optic can escape the casing along a beam axis.

4. A work light comprising:

a) a high power LED that requires a heatsink for operation in a normal working environment while preserving a useful life in prolonged use,

b) an optic associated with the LED such that a beam edge of light radiating from the LED is changed by the optic to produce a beam for use in working for prolonged periods wherein the beam edge has a different sharpness,

c) a heatsink for use with the LED to preserve useful working life of the LED when operated in prolonged use,

d) a casing substantially enclosing the LED and optic, and the casing housing the, and

e) a transparent cover in the casing through which the beam of light from the optic can escape the casing along a beam axis.

35. A work light comprising:

a) at least one LED and an LED mounting member to which the at least one LED is mounted,

b) a heatsink thermally connected to at least one LED,

c) a casing within which the LED assembly and heatsink are mounted,

wherein the casing has a transparent cover through which light emitting from the LED can escape the casing, and

wherein the casing has openings through which heat from the heatsink may be transferred to ambient air external to the casing to provide cooling for the heatsink

36. The work light of claim 35 wherein the openings are adjacent to the heatsink.

37. The work light of claim 35 wherein the openings are dimensioned to prevent accidental access through the casing to the heatsink.

38. The work light of claim 35 wherein the casing is primarily made from a rigid plastic.

39. The work light of claim 35 wherein the casing is primarily made from an electrically insulative material.

40. The work light of claim 35 further comprising a hook mounted to the casing on a ball-and-socket joint such that the hook can be rotated about 360 degrees relative to the casing when in use, and further comprising a recess in the casing such that the hook can be rotated on the ball-and-socket joint to be received within the recess when not in use.

41. The work light of claim 35 further comprising a hook mounted to the casing on a ball-and-socket joint such that the hook can be rotated about 360 degrees relative to the casing when in use and such that the hook can be rotated on the ball-and-socket joint to lay flat against the casing when not in use.

42. The work light of claim 41 wherein the casing has a recess against which the hook lays flat, the recess recessed sufficiently to present a generally smooth outer contour for the work light when the hook is in the recess, while allowing manual access to the hook.

43. The work light of claim 35 wherein the openings are in a non-planar surface of the casing such that the openings are not blocked when the non-planar surface is placed adjacent a planar surface.

44. The work light of claim 41 wherein the non-planar surface is an arcuate surface.

45. The work light of claim 35 wherein the overall width of the work light is approximately 60 millimetres or less, the overall depth is approximately 43 millimetres or less, and the overall height is approximately 301 millimetres or less, and the transparent cover is in the casing across a portion of the width of the work light

46. The work light of claim 35 wherein the casing further comprises a handle portion and a head portion, and the at least one LED and LED mounting member and heatsink are mounted in the head portion.

47. The work light of claim 46 wherein the handle has a cavity for receiving batteries to power the LEDs.

48. The work light of claim 35 further comprising a connection through which the work light can receive energy for the LEDs.

49. The work light of claim 46 wherein the connection is for receiving a battery source of energy.

50. The work light of claim 46 wherein the connection is for receiving a further connection to a source of energy external to the casing.

51. The work light of claim 46 further comprising circuitry between the LEDs and the source of energy for controlling the flow of energy from the source of energy to the LEDs.

52. The work light of claim 35 wherein the casing is configured to accept a battery source of energy and a connection for receiving a source of energy external to the casing, such that the battery source of energy and the connection for receiving a source of energy external to the casing are interchangeable.

53. The work light of claim 35 wherein the light has a longitudinal axis with which the handle and head are generally aligned

54. The work light of claim 53 wherein the transparent cover over the LEDs is directed out of line with the longitudinal axis.

55. The work light of claim 53 wherein the transparent cover over the LEDs is directed generally perpendicular to the longitudinal axis.

56. The work light of claim 53 wherein the openings open out of line with the longitudinal axis.

57. The work light of claim 53 wherein the openings open generally perpendicular to the longitudinal axis.

58. The work light of claim 53 wherein the openings are elongate slots extending generally parallel to the longitudinal axis.

59. The work light of claim 35 wherein at least one LED is plurality of LEDs and the LEDs are mounted substantially on one plane to emit light substantially perpendicular to the plane.

60. The work light of claim 59 wherein the LEDs are mounted substantially along a line in the plane.

61. The work light of claim 35 wherein the light further comprises one optic for each LED of the at least one LED, each optic associated with its respective LED such that radiation emitted by the LEDs and passing through the optics produces a beam that has a beam angle of between approximately 40 degrees and 90 degrees.

62. The work light of claim 61 wherein the beam has a central beam axis that is generally perpendicular to the longitudinal axis of the light.

63. The work light of claim 35 wherein dissipation of heat from the heatsink maintains the temperature of the outside surface of the LEDs below approximately 75 degrees Celsius in a range of ambient temperatures below approximately 35 degrees Celsius.

64. The work light of claim 35 wherein the heatsink is set back from an adjacent internal surface of the casing.

65. The work light of claim 35 wherein light further comprises an air gap between the heatsink and the adjacent internal surface of the casing.

80. The LED work light of claim 61 wherein the at least one light emitting diode nominally has a lambertian radiation pattern.

70. A work light comprising:

a) at least one LED and an LED mounting member to which the at least one LED is mounted,

b) a heatsink thermally connected to the at least one LED,

c) a casing within which the at least one LED and heatsink are mounted,

wherein the at least one LED emits light about a central beam axis,

wherein the casing has a head section,

wherein the head section has a transparent cover through which light emitting from the LED assembly can escape the casing,

wherein the heatsink has three dimensions;

depth, width and height,

wherein the at least one LED is mounted adjacent and in thermal contact with the heatsink along the central beam axis in an opposite direction to which the at least one LED emits light,

wherein the depth of the heatsink is measured along the central beam axis,

wherein the width and height of the heatsink are measured perpendicular to the depth and to one another,

wherein the head section follows the general profile of the heatsink, and

wherein the depth of the heatsink is substantially less than the width of the heatsink and substantially less than the height of the heatsink, such that the work light uses less space in the direction in which light is desired.

76. A work light comprising:

a) at least one LED and an LED mounting member to which the at least one LED is mounted, and the at least one LED emits light about a central beam axis,

b) a heatsink thermally connected to the at least one LED,

c) a casing within which the at least one LED and an LED mounting member and heatsink are mounted,

wherein the casing comprises a handle section and a head section,

wherein the casing comprises two casing portions that prior to assembly allow the insertion of the at least one LED and an LED mounting member and heatsink into one of the casing portions, and after assembly the casing portions together form the handle section and head section, and

wherein the head section has a transparent cover through which light emitting from the at least one LED can escape the casing.

77. A work light comprising:

a) a high power LED that requires a heatsink for operation in a normal working environment while preserving a useful life in prolonged use,

b) a heatsink for use with the LED to preserve useful working life of the LED when operated in prolonged use,

c) a casing of a substantially electrically insulative material substantially enclosing the LED and heatsink such that components inside the casing are prevented from accidental contact with an operator,

d) a transparent cover in the casing through which a beam from the LED can escape the casing along a beam axis,

wherein the heatsink and the LEDs together occupy a dimension generally parallel to the beam axis,

wherein the casing has a head section and a handle section,

wherein the LEDs and heatsink are in the head section,

wherein the head section has an elongate profile that is smaller in a dimension generally parallel to the beam axis of the light than in any dimension generally perpendicular to the beam axis,

wherein the handle is elongate and extends away from the head section, and

wherein the handle extends away from the head section outside a volume bounded by the dimensions of the head section generally perpendicular to the beam axis such that the handle does not increase the depth of the head section generally parallel to the beam axis within that volume.