Lighting device

Abstract

A lighting device includes a light source, a base and an articulated support. The support has a first arm which is rotatable relative to the base about a first axis, a second arm upon which the light source is mounted, and a joint section which connects the second arm to the first arm for movement relative thereto about a second axis which is parallel to the first axis. The second arm is also moveable relative to the joint section about a third axis which intersects, and is orthogonal to, the second axis to change the orientation of the light source relative to the base.

Claims

1. A lighting device comprising: a light source; a base; and a support; wherein the support comprises a first arm which is rotatable relative to the base about a first axis, a second arm upon which the light source is mounted, the second arm being substantially parallel to the first arm, the second arm comprising an upper wall and a lower wall that together define a recess, and a joint section which connects the second arm to the first arm for movement relative thereto about a second axis which is parallel to the first axis, the joint section comprising a shaft received in the recess of the second arm; wherein the first arm of the support is mounted on a body which is rotatable relative to the base about the first axis, the first axis extending along a longitudinal axis of the body, the first arm of the support extending substantially orthogonal to the longitudinal axis of the body, and wherein the second arm is moveable around 360° about the shaft relative to the joint section about a third axis which is coaxial with the shaft and which intersects, and is orthogonal to, the second axis.

2. The device of claim 1, wherein the shaft comprises one or more shaft recesses angularly spaced about the shaft, and wherein the second arm comprising a detent which is received by one of the recesses depending on the orientation of the second arm.

3. The device of claim 2, wherein the shaft comprises two shaft recesses which are spaced apart by 180°, and which are arranged such that, when the detent is received by a shaft recess, an optical axis of the light source is parallel to the first axis.

4. The device of claim 1, wherein the joint section moves with the second arm about the second axis.

5. The device of claim 1, comprising a spigot which extends along the second axis, and wherein the joint section comprises a recess for receiving the spigot.

6. The device of claim 1, comprising at least one retainer for retaining the second arm in one or more orientations relative to the joint section.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) Preferred features of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

(2) FIG. 1 is a perspective view, from above, of a lighting device, in which the lighting device is in a room lighting configuration;

(3) FIG. 2 is a front view of the lighting device as illustrated in FIG. 1;

(4) FIG. 3 is a side view of the lighting device as illustrated in FIG. 1;

(5) FIG. 4 is a close up of area A indicated in FIG. 1;

(6) FIG. 5 is a top view of the lighting device as illustrated in FIG. 1;

(7) FIG. 6 is a perspective view of a light reflective member which is housed within a body of the lighting device;

(8) FIG. 7 is a sectional view taken along line B-B in FIG. 5;

(9) FIG. 8 is a close up of area C indicated in FIG. 7;

(10) FIG. 9 is a perspective view, from above, of the lighting device, in which the lighting device is in a first task lighting configuration;

(11) FIG. 10 is a close up of area D indicated in FIG. 9;

(12) FIG. 11 is a top view of the lighting device illustrated in FIG. 9;

(13) FIG. 12 is a perspective view, from above, of the lighting device, in which the lighting device is in a second task lighting configuration;

(14) FIG. 13 is a close up of area E indicated in FIG. 12;

(15) FIG. 14 is a perspective view, from above, of the lighting device, in which the lighting device is in a third, fully extended task lighting configuration;

(16) FIG. 15 is a perspective view, from above, of the lighting device, in which the lighting device is in a fourth task lighting configuration;

(17) FIG. 16 is a perspective view, from above, of the lighting device, in which the lighting device is in a first angled configuration;

(18) FIG. 17 is a perspective view, from above, of the lighting device, in which the lighting device is in a second angled configuration; and

(19) FIG. 18 is a perspective view, from above, of the lighting device, in which the lighting device is in an uplighting configuration.

DETAILED DESCRIPTION OF THE DISCLOSURE

(20) An embodiment of a lighting device 10 of the present invention will be described with reference to FIGS. 1 to 18. In this embodiment, the lighting device 10 is in the form of a desk lamp, but alternative embodiments include a floor-standing lamp and a wall-mounted light. In overview, the lighting device 10 comprises a body 12 mounted on a base 14, a support 16 connected to the body 12, and a light source 18 which is supported by the support 16. The support 16 is articulated, which allows a user to move the light source 18 relative to the body 12 to allow the lighting device 10 to adopt a range of different configurations.

(21) With reference first to FIGS. 1 to 3, the body 12 comprises a tubular housing 20 which in this embodiment is in the form of a pipe having a constant circular cross-section. The housing 20 is mounted on the base 14 so that the longitudinal axis of the housing 20 extends orthogonal to the base 14, with the base 14 being shaped such that the housing 20 is vertical when the base 14 is located on a horizontal surface. In this embodiment, the housing 20 is formed from an opaque material, which may be a plastics or metallic material. The housing 20 includes light permeable sections in the form of two perforated sections 22 which are located on opposite sides of the housing 20 and which each extend partially about the longitudinal axis of the body 12 and at least half way along the length of the body 12. As an alternative, the body 12 may comprise a transparent tubular housing, again preferably in the form of a pipe having a constant circular cross-section, and a perforated sleeve extending about the housing.

(22) As shown in FIG. 11, the housing 20 has an open upper end 24 which is remote from the base 14, and which defines an aperture 26 through which light enters the body 12 from the light source 18. The upper end 24 of the housing 20 is located in a plane which is substantially orthogonal to the longitudinal axis of the housing 20. With reference also to FIG. 7, the lower end 28 of the body 12 is closed by a stop 30. During assembly, the stop 30 is received by an annular central section 32 of the base 14 so that an annular flange 34 of the stop 30 overlies an inner annular flange 36 of the central section 32 of the base 14. A threaded cap 38 is then secured to lower end of the stop 30. The inner annular flange 36 becomes sandwiched between the stop 30 and the cap 38, which secures the body 12 to the base 14 whilst enabling the body 12 to rotate relative to the base 14 about a first axis X.sub.1, which is collinear with the longitudinal axis of the body 12.

(23) In this embodiment, a light reflecting member 40 is located within the housing 20 for guiding light received from the aperture 26 towards the perforated sections 22 of the body 12. The light reflecting member 40 is illustrated in FIG. 6. The light reflecting member 40 comprises an annular upper end 42 and a recessed lower end 44 which receives a spigot 46 upstanding from the stop 30 to attach the stop 30 to the light reflecting member 40. The light reflecting member 40 may be attached to the internal surface of the housing 20 using an adhesive. The light reflecting member 40 is generally in the shape of an I-beam to provide structural support to the body 12, and is preferably formed from a metallic material, such as aluminium. The light reflecting member 40 comprises two concave reflective surfaces 48 arranged back to back, and which extend between the upper end 42 and the lower end 44 of the light reflecting member 40. When the light reflecting member 40 is inserted into the housing 20 and mounted on the spigot 46, each reflective surface 48 directs light that has entered the housing 20 through the aperture 26 towards a respective perforated section 22 of the body 12.

(24) The support 16 is connected to the body 12 so that the support 16 extends outwardly from the body 12, preferably so that the support 16 is orthogonal to the longitudinal axis of the body 12. In this embodiment, the support 16 is connected to the upper end 24 of the body 12. The support 16 comprises a first joint section 50 which is attached to the upper end 24 of the body 12, for example using an adhesive so that the first joint section 50 is rigidly attached to the housing 20. The support 16 thus rotates with the body 12 about the first axis X.sub.1. With reference again to FIG. 7, the first joint section 50 comprises an annular section 52 which has the same external diameter as the housing 20 so that together the housing 20 and the first joint section 50 have a unitary appearance, and which enables light to pass therethrough towards the aperture 26. The first joint section 50 may also include a pair of reflective surfaces 54, shown in FIG. 9, for guiding light towards the perforated sections 22 of the body 12.

(25) The first joint section 50 comprises a hollow shaft 56 which extends outwardly from the annular section 52, preferably substantially orthogonally to the first axis X.sub.1. A first arm 58 of the support 16 comprises a chamber 60 which extends the length of the first arm 58 and which receives the shaft 56 as a first end of the first arm 58 is slid on to the hollow shaft 56. The first arm 58 is then secured to the first joint section 50 using bolts or screws 62. The first arm 58 comprises two parallel side walls 64, a lower wall 66 located perpendicularly between the lower ends of the side walls 64, and an upper wall 68 which is parallel to the lower wall 66, and located generally midway between the upper end and lower end of the side walls 64. The chamber 60 is located between the lower wall 66 and the upper wall 68.

(26) A second joint section 70 of the support 16 is connected to the second end of the first arm 58, for example using an adhesive. With reference also to FIG. 8, similar to the first joint section 50 the second joint section 70 comprises a hollow shaft 72 which is received by the chamber 60. The second joint section 70 comprises a generally cylindrical spigot 74 which, when the second joint section 70 is attached to the first arm 58 of the support 16, has a longitudinal axis which is parallel to the longitudinal axis of the body 12.

(27) A third joint section 76 is mounted on the second joint section 70 so that the third joint section 76 is rotatable relative to the second joint section 70 about a second axis X.sub.2 which is collinear with the longitudinal axis of the cylindrical spigot 74. The third joint section 76 is generally cylindrical in shape, and comprises a cylindrical recess 78 which receives the cylindrical spigot 74 as the third joint section 76 is mounted on the second joint section 70. The spigot 74 includes a circular recess 79a which receives a grub screw 79b carried by the third joint section 76 to retain the third joint section 76 on the second joint section 70 whilst preventing the third joint section 76 from lifting away from the second joint section 70 during use of the lighting device 10.

(28) A second arm 80 of the support 16 is mounted on the third joint section 76 so that the second arm 80 pivots about the second axis X.sub.2 with rotation of the third joint section 76 about that axis. Similar to the first arm 58, the second arm 80 comprises two parallel side walls 82, a lower wall 84 located perpendicularly between the lower ends of the side walls 82, and an upper wall 86 which is parallel to the lower wall 84, and located generally midway between the upper end and lower end of the side walls 82. The lower wall 84 and the upper wall 86 define a cylindrical recess 88 at one end of the second arm 80 which receives a hollow shaft 90 which extends outwardly from the third joint section 76 substantially orthogonal to the second axis X.sub.2 so that the second arm 80 is substantially parallel to the first arm 58. This also enables the second arm 80 to rotate relative to the third joint section 76, and thus relative to the first arm 58, about a third axis X.sub.3 which is orthogonal to, and which preferably intersects, the second axis X.sub.2. The lower wall 84 and the upper wall 86 also define therebetween a chamber 92 which extends from the recess 88 to the second end of the second arm 80.

(29) The light source 18 is mounted on the second end of the second arm 80. With reference to FIG. 7, the light source 18 comprises a plurality of light emitting diodes (LEDs) 94 centred on an optical axis O of the light source 18. The LEDs 94 are surrounded by an annular reflector housing 96 for directing light emitted from the LEDs 94 away from the light source 18. The LEDs 94 are mounted on a heat conductive plate 98, and connected electrically to a printed circuit board (PCB) 100. The PCB 100 is connected to one or more wires or conductive tracks which extend from the PCB 100 within the chambers 60, 92 and the hollow shafts 56, 72, 90 to an electrical contact (not shown) located on the first joint section 50. This electrical contact engages with an electrical contact (not shown) located on the upper end of the body 12 when the first joint section 50 is connected to the body 12. A further wire or conductive track extends through the body 12 to a further electrical contact located on the stop 30, to which a mains power supply may be connected. Providing these electrical contacts can enable the support 16 to be detachably connectable to the body 12 if so desired, for example for transportation purposes.

(30) The heat conductive plate 98 is mounted on a heat pipe 102 so that heat emitted from the LEDs 94 during use of the lighting device 10 is transferred to the heat pipe 102. The heat pipe 102 protrudes outwardly from the light source 18, and is supported by the upper wall 86 of the second arm 80.

(31) FIGS. 1 to 5 and FIGS. 7 to 8 illustrate the lighting device 10 in a first, or “room lighting” configuration. In this first configuration, the second arm 80 is oriented relative to the first arm 58 so that the second arm 80 is parallel to, and substantially overlies, the first arm 58. In this configuration, the light source 18 is positioned directly over the open upper end 24 of the body 12. The reflector housing 96 has substantially the same external diameter as the housing 20 of the body 12, and the heights of the joint sections 50, 70, 76 and the reflector housing 96 are chosen so that the open upper end 24 of the body 12 is substantially fully occluded by the light source 18, that is, so that there is substantially no stray light emitted from the lighting device 10 as it passes from the light source 18 and into the body 12. The light is reflected by the reflective surfaces within the body 12 towards the perforated sections 22 of the body 12, from which the light is emitted into the external environment. In this first configuration, heat radiated from the heat pipe 102 during use of the lighting device 10 passes through an aperture 104 located between the upper ends of the side walls 82 of the second arm 80 to enter the external environment.

(32) From the first configuration, the second arm 80 may be rotated manually about the second axis X.sub.2 so as to move the light source 18 laterally away from the open upper end 24 of the body 12, and so place the lighting device 10 in a second, “task lighting” configuration, in which the light emitted from the light source 10 can illuminate directly a work surface or other task area. By way of example, FIGS. 9 to 11 illustrate the lighting device 10 in a first tasking lighting configuration following a clockwise rotation of the second arm 80 about the second axis X.sub.2, and FIGS. 12 to 13 illustrate the lighting device 10 in a second tasking lighting configuration following an anti-clockwise rotation of the second arm 80 about the second axis X.sub.2. From either of these two configurations, the second arm 80 may be rotated further so that the lighting device 10 adopts a third, fully extended configuration, illustrated in FIG. 14, in which the first arm 58 and the second arm 80 are substantially parallel and linearly arranged, and the light source 18 is located furthest from the body 12. In any of these task lighting configurations, the user may adjust the angular position of the light source 18 relative to the base 14 by rotating the body 12 about the first axis X.sub.1.

(33) From each of these first to third task lighting configurations, the lighting device 10 may be returned to the room lighting configuration by rotation of the second arm 80 about the second axis X.sub.2. To ensure an accurate alignment of the light source 18 with the body 12 as the lighting device 10 returns to its room lighting configuration, the lighting device 10 includes a biasing mechanism for urging the lighting device 10 into its room lighting configuration as the light source 18 approaches the body 12. In this embodiment, the biasing mechanism comprises a detent 106 which is located on the upper wall 68 of the first arm 58, and which is moveable along a rod 108 which extends between the second joint section 70 and a stop member 110 attached to the upper wall 68. A compression spring 112 extending about the rod 108 urges the detent 106 away from the stop member 110. The detent 106 includes a roller 114 which is urged against the external cylindrical surface of the third joint section 76, so that the roller 114 engages a circular track extending about the third joint section 76. The concave recess 116 is formed on the track. The recess 116 is positioned on the track so that the roller 114 is located in the recess 116 when the lighting device 10 is in its first configuration. As the lighting device 10 moves towards its first configuration, the roller 114 beings to enters the recess 116 and, under the biasing force of the spring 112, urges the third joint section 76 to rotate about the second axis X.sub.2 until the roller 114 has fully entered the recess 116.

(34) In each of the first to third task lighting configurations discussed above, the optical axis O of the light source 18 remains substantially parallel to the longitudinal axis of the body 12. These task lighting configurations are most useful for illuminating a task area on a work surface on which the lighting device 10 is located. At other times, the user may wish to illuminate other surfaces, such as reading material held by the user, or a wall or a ceiling of the room in which the lighting device 10 is located. In these instances, the user may change the orientation of the optical axis O of the light source 18 by rotating the second arm 80 about the third axis X.sub.3.

(35) By way of example, FIG. 15 illustrates the lighting device in a fourth task lighting configuration, in which, similar to the first to third task lighting configurations described above, the optical axis O is parallel to the longitudinal axis of the body 12 and the light source 18 is facing towards the work surface on which the lighting device 10 is located. This may be referred to as a downlighting configuration of the lighting device 10. To angle the optical axis O to the longitudinal axis of the body 12, the user grasps the second arm 80 and rotates it about the hollow shaft 90, and thus about the third axis X.sub.3. By way of example, FIG. 16 illustrates the lighting device 10 in a first tasking lighting configuration following an anti-clockwise rotation of the second arm 80 about the third axis X.sub.3, and FIG. 17 illustrates the lighting device 10 in a second tasking lighting configuration following a clockwise rotation of the second arm 80 about the third axis X.sub.3. From either of these two “angled” configurations, the second arm 80 may be rotated further about the third axis X.sub.3 so that the lighting device 10 adopts an “uplighting” configuration, illustrated in FIG. 18, in which the optical axis O is again parallel to the longitudinal axis of the body 12 but the light source 18 is facing away from the work surface on which the lighting device 10 is located.

(36) Again, as it is anticipated that the lighting device 10 may be more frequently used in either a downlighting configuration or an uplighting configuration, the lighting device 10 comprises a mechanism for retaining the lighting device in either of these two configurations. With reference to FIG. 8, the hollow shaft 90 includes recesses 124 which are formed in, and angularly spaced about, the outer surface of the hollow shaft 90. In this embodiment, the hollow shaft 90 comprises two recesses 124 which are angularly spaced by 180°, but further recesses 124 may be provided if so desired; for example, four recesses may be arranged about the hollow shaft 90 and angularly spaced by 90°. The second arm 80 includes a detent 126 which is biased by a spring 128 towards the hollow shaft 90, and so enters one of the recesses 124 when the lighting device 10 adopts either a downlighting or an uplighting configuration. The force of the spring 128 is selected so that the lighting device 10 remains in the selected configuration until the user grasps the second arm 80 of the support 16 and twists it about the third axis X.sub.3 to urge the detent 126 away from the recess 124.

(37) As in the first configuration, when the lighting device 10 is in a downlighting configuration heat radiated from the heat pipe 102 during use of the lighting device 10 passes through the aperture 104 located between the upper ends of the side walls 82 of the second arm 80 to enter the external environment. To improve the radiation of heat from the heat pipe 102 when the lighting device 10 is in an angled configuration, each side wall 82 of the second arm 80 comprises a series of apertures 130 through which heat radiated by the heat pipe 102 enters the external environment. As illustrated in FIGS. 9 and 12, for example, in this embodiment each side wall 82 comprises a row of five apertures 130. Each of these apertures 130 has substantially the same size and shape, and there is a substantially constant spacing between adjacent apertures 130 so that there is a relatively uniform heat emission along the side walls 82.