Heat insulation supporting piece and lamp

Abstract

An insulating support for holding an insulating material spaced apart from a luminaire, the insulating support comprising: a body portion defining a cylindrical surface; and an end cap supported by the main body portion, at least the end cap comprising at least one vent hole, and the end cap being rotatable relative to the main body portion to stay in a first position or a second position spaced apart from the first position in a length direction of a longitudinal axis of the cylindrical surface of the main body portion.

Description

Technical Field

[0001] The utility model relates to a heat-insulating support piece, a lamp and a method for keeping a heat-insulating material and a heat source of an electric lamp (such as a downlight) separated. Background Art

[0002] Traditional downlights are mounted in a support structure (e.g. a ceiling) that also supports a layer of insulation. If the insulation comes into contact with the downlight, it can cause an unwanted build-up of heat. Depending on the type of lighting fixture, this heat build-up can present a fire risk, particularly for LED-type fixtures, and can significantly reduce the efficiency and durability of the associated driver.

[0003] To address the problem of undesirable heat buildup, various proposals have been made for keeping insulation away from downlights. However, some of these proposals are cost prohibitive or difficult to install, while others fail to optimize the reduction of heat buildup given the size of the space environment in which the downlight and insulation are installed. Utility Model Content

[0004] The utility model aims to provide a heat-insulating support, which is conducive to optimizing the reduction of heat accumulation to a greater extent in view of the limited available space.

[0005] According to one aspect of the utility model, there is provided a thermal insulation support for keeping a thermal insulation material separated from a lamp, the thermal insulation support comprising a main body portion defining a cylindrical surface; and an end cap supported by the main body portion, at least the end cap comprising at least one ventilation hole, and the end cap being rotatable relative to the main body portion to stay in a first position or a second position, the second position being separated from the first position in the length direction of the longitudinal axis of the cylindrical surface of the main body portion.

[0006] At least one of the body portion and the end cap may be provided with a cable entry hole through which a power cable may extend to the lamp. The cable entry hole may be located at the distal end of the end cap, furthest from the body portion, but is preferably located between the end regions of the end cap.

[0007] The end cap may be non-releasably fixed to the body portion. Alternatively, the end cap may be removable and replaceable from the body portion.

[0008] The thermal insulation support may include a stopper to prevent rotational movement of the end cap and the main body from one relative position to a second relative position. At least two of the stoppers may be provided to prevent relative movement of the end cap and the main body from any one of two or more relative positions.

[0009] The at least one vent may be located at a distal end of the end cap, furthest from the body portion, but is preferably disposed between the ends of the end cap, for example facing in a generally radially outward direction.

[0010] The body portion may define a cylindrical surface which is an outwardly facing surface. In an alternative configuration, the body portion may define a cylindrical surface which is a radially inwardly facing surface.

[0011] The end cap and the body portion may include confronting surfaces defining a threaded structure for guiding relative movement of the end cap and the body portion between the first position and the second position.

[0012] One of the end cap and the main body portion may include a helical extension groove that engages with a protrusion on the other of the end cap and the main body portion, whereby relative rotation of the end cap and the main body portion forces the protrusion to move from one end of the helical extension groove to the other end. Preferably, two helical extension structures are provided and positioned at substantially diametrically opposed locations of the main body portion or the end cap.

[0013] At least one of the helically extending slots may include a stop means to prevent the protrusion from moving freely along at least a portion of the length of the slot. The stop means may include a cam surface which locally reduces the width of the slot.

[0014] The body portion may be an integral part of the luminaire. It may be a housing for one or more other components of the driver and the LED light source. The end caps may be non-releasably secured to the body portion, and a power supply cable for the luminaire may be arranged to extend through the insulating support before the connector is fitted to the distal end of the cable. Thus, the insulating support, cable and connector may be factory fitted to the luminaire.

[0015] In an alternative construction of the insulating support of the present invention, the main body portion may be a tubular main body portion which may be positioned to extend around a housing portion of a luminaire. Thus, the insulating support of the present invention may be reassembled to a luminaire, particularly if the main body portion and the end caps are selectively separable from one another. Thus, if the luminaire has a cable with the distal end of the cable preassembled with a connector, the connector may be fed through the tubular main body portion before the end cap is secured to the main body portion, with the cable then extending through a slot or other such aperture, such as an aperture defined by the end cap or the main body portion.

[0016] The main body of the insulating support may serve as a housing for components containing the LED light source. The LED light source may be fixed in position relative to the housing. The housing may contain a heat sink, and the heat sink may be fixed in position relative to the housing.

[0017] According to another aspect of the present invention, a lamp comprising the heat insulating support of the present invention is provided. The lamp may include the heat insulating support having a tubular main body portion non-rotatably fixed to the lamp, or the main body portion of the heat insulating support may be a component of the lamp.

[0018] The utility model also provides a method for keeping a heat insulating material separated from a heat source of an electric lamp (such as an LED downlight), the method comprising providing the lamp with the heat insulating support member of the utility model. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0020] Figure 1 is a perspective view of a lamp according to an embodiment of the present utility model;

[0021] Figure 2 yes Figure 1 Side view of the lamp;

[0022] Figure 3 Shows Figure 1 detail of a portion of a light fixture;

[0023] Figure 4a and Figure 4b They are shown respectively Figure 1 The thermally insulating support of the luminaire in the unextended and extended states;

[0024] Figure 5 shows a side view of a lamp according to a second embodiment of the present invention, and

[0025] Figure 6 A portion of a heat insulating support according to a third embodiment of the present invention is shown. DETAILED DESCRIPTION

[0026] In a first embodiment of the present invention, a luminaire in the form of an LED downlight 10 comprises a body portion 11 defining a generally cylindrical outer surface 12 .

[0027] The main body 11 in this embodiment is a fire-resistant shell, one end of which supports the outer ring 13 and the lens unit 14. The LED light source and the heat sink are firmly fixed in the shell.

[0028] The housing 11 additionally provides support for two diametrically opposed support arms 15 extending from adjacent the outer ring 13 to the side of the housing but spaced therefrom. The end 16 of each support arm furthest from the outer ring is provided with a spring 17 for providing a biasing force to a respective spring loaded arm 18 in use, thereby securing the luminaire to a ceiling or other such support structure in a known manner.

[0029] The housing 11 also provides support for switches 20 and 21 respectively, so as to control the wattage and color temperature of the light emitted by the LED in the downlight.

[0030] In order to keep the insulation material away from the LEDs and components contained in the housing 11, the downlight is provided with a removable end cap 25. Figure 2 As best shown, the end cap 25 is provided with a plurality of ventilation holes 26 and a cable hole 27 for a power cable 28 .

[0031] The end cap 25 includes a pair of diametrically opposed spirally extending grooves 30 (see Figure 3 ), each helically extending groove 30 receives a corresponding one of a pair of diametrically opposed projections 31 extending radially outwardly from the outer surface 12 of the housing 11. A small cam surface 32 is provided near each end of the groove 30, which serves as a stop to prevent relative rotational movement of the end cap and the housing body from one extreme position to the other.

[0032] Optionally, additional cam surfaces may be provided between the ends of the slot so that a pair of cam surfaces will provide a means for securing the end cap in an intermediate position.

[0033] In view of the above, it can be understood that the end cover can be rotated relative to the shell body 11 so that the end cover can be located Figure 4a The first position shown and Figure 4b A second extended position is shown, and in the second extended position the ventilation holes of the end cap are spaced further away from the end of the supporting outer ring 13 of the housing.

[0034] The provision of a pair of spirally extending slots 30 and housing body protrusions 31 (which can snap into position at either end of the corresponding slots by simple rotation of the end caps) allows the overall height of the luminaire to be easily adjusted on site taking into account the limited space of the insulating cavity in which the luminaire is installed. Figure 4a In the orientation of , the end cap 25 is in a position where the downlight can be installed in an insulated space with limited depth, while Figure 4b In the orientation, the downlight can advantageously have better ventilation by further isolating the insulating material from the heat-sensitive components of the luminaire.

[0035] The heat insulation support member of the present invention does not necessarily have to adopt a spiral extension groove. Figure 5In the second embodiment of the present invention shown, the surface 50 of the housing 51 may be provided with a threaded structure 51 that engages with a complementary threaded structure on the inner surface of the cylindrical portion 52 of the end cap 53 .

[0036] In reference Figure 6 In the third embodiment of the utility model shown, a heat-insulating support is provided, which includes an end cap (not shown) corresponding to the end cap of the first embodiment of the utility model. However, unlike the end cap that can rotate relative to the protrusion provided on the lamp housing, the heat-insulating support includes a tubular main body portion 60. The outer surface 61 of the main body portion includes a pair of protrusions 62 positioned completely opposite to each other, which correspond to the aforementioned protrusions to engage with the grooves of the end cap. The heat-insulating support can be used with a downlight of a type known to date, in which the main body portion 60 extends around the housing of the downlight between the housing and a structure such as the support arm 15 of the aforementioned support spring biasing arm 18.

Claims

1. A heat-insulating support member for keeping heat-insulating materials separated from lamps, characterized in that: The thermal insulation support member includes: a main body portion, which defines a cylindrical surface; and an end cover, which is supported by the main body portion, at least the end cover includes at least one ventilation hole, and the end cover can be rotated relative to the main body portion to stay in a first position or a second position, and the second position is separated from the first position in the length direction of the longitudinal axis of the cylindrical surface of the main body portion.

2. The heat insulating support according to claim 1, characterized in that: At least one of the main body and the end cover is provided with a cable entry hole to receive a power cable of the lamp.

3. The heat insulating support member according to claim 2, characterized in that: The cable entry location is positioned between the end regions of the end caps.

4. A thermally insulating support according to any one of the preceding claims, characterised in that The at least one ventilation aperture is disposed between end regions of the end cap.

5. The heat insulating support according to claim 4, characterized in that: The at least one vent aperture faces in a generally radially outward direction from the end cap.

6. The heat insulating support according to any one of claims 1 to 3, characterized in that: Stop means are included to prevent relative rotational movement of the end cap and the main body portion from one relative position to a second relative position.

7. The heat insulating support member according to claim 6, characterized in that: At least two of the stop devices are included.

8. The thermal insulation support according to any one of claims 1 to 3, characterized in that: The end cap and the main body portion include facing surfaces defining a threaded structure for guiding relative movement of the end cap and the main body portion between the first position and the second position.

9. The thermal insulation support according to any one of claims 1 to 3, characterized in that: One of the end cap and the body portion includes a helically extending groove that engages a protrusion on the other of the end cap and the body portion, whereby relative rotation of the end cap and the body portion forces the protrusion to move from one end of the helically extending groove to the other end.

10. The heat insulating support according to claim 9, characterized in that: The invention comprises two spirally extending grooves, and the two spirally extending grooves are arranged at completely opposite positions of the main body part or the end cover.

11. The heat insulating support member according to claim 9, characterized in that: At least one of the helically extending slots includes a stop means to prevent free movement of the protrusion along at least a portion of the length of the slot.

12. The heat insulating support according to claim 11, characterized in that: The stop means comprises a cam surface which locally reduces the width of the slot.

13. The thermal insulation support according to any one of claims 1 to 3, characterized in that: The end cap is non-releasably secured to the body portion.

14. The thermal insulation support according to any one of claims 1 to 3, characterized in that: The end cap is removable from the body portion and replaceable.

15. The thermal insulation support according to any one of claims 1 to 3, characterized in that: The cylindrical surface of the body portion is the outwardly facing surface.

16. The thermal insulation support according to any one of claims 1 to 3, characterized in that: The cylindrical surface of the body portion is a radially inwardly facing surface.

17. The thermal insulation support according to any one of claims 1 to 3, characterized in that: The main body is a component of the lamp.

18. The heat insulating support according to claim 17, characterized in that: The main body portion is a housing that accommodates components of the LED light source.

19. The heat insulating support according to claim 18, characterized in that The light source is fixed in position relative to the housing.

20. The heat insulating support according to claim 18 or 19, characterized in that: The housing houses a heat sink, and wherein the heat sink is fixed in position relative to the housing.

21. The thermal insulation support according to claim 17, characterized in that: A power cable of the lamp extends through the thermally insulating support.

22. The thermal insulation support according to any one of claims 1 to 3, characterized in that: The body portion is a tubular body portion positionable around a housing portion of the luminaire.

23. A lamp, characterized in that: Comprising a thermally insulating support according to any one of the preceding claims.

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