WO2010049517A1

WO2010049517A1 - A mounting arrangement for light sources and corresponding method

Info

Publication number: WO2010049517A1
Application number: PCT/EP2009/064355
Authority: WO
Inventors: Alessandro Bizzotto; Alessandro Scordino; Francesco Bianco; Peter Sachsenweger
Original assignee: Osram Gesellschaft mit beschränkter Haftung; Osram S.P.A - Societa' Riunite Osram Edison Clerici
Priority date: 2008-10-31
Filing date: 2009-10-30
Publication date: 2010-05-06

Abstract

A mounting arrangement (100) for light sources such a high power LEDs (106) for street lighting applications, includes a base plate (102, 702) for fixing to a mounting surface such as the head of pole and a lamp (104) carrying one or more light sources (106). The base plate (102, 702) and the lamp (104) are provided with: -i) complementary mechanical coupling formations (1024, 1068; 1025, 1070) for snap-like coupling the lamp (104) to the base plate (102, 702); and -ii) complementary electrical coupling formations providing electrical connection for the light source(s) (106) simultaneously with mechanical connection of the lamp (104) to the base plate (102, 702).

Description

DESCRIPTION of the industrial invention entitled:

"A mounting arrangement for light sources and corresponding method"

TEXT OF THE DESCRIPTION

Field of the invention

This disclosure relates to mounting arrangements for light sources.

This disclosure was devised with specific attention paid to its possible application to mounting arrangements for arrays of high power LED modules for use e.g. in street lighting systems.

Description of the related art

Conventional mounting arrangements for LED lighting modules for use, e.g. in street lighting systems, require a large number of non-interactive solutions, with complex mechanical connections and additional fixed components (e.g. screws, gluing, ...) without any flexibility in assembling/disassembling the arrangement. This leads to bulky and complex solutions that are unable to match the intrinsic compactness of LED light sources and make replacement of the light source (to be effected mostly at the head of a pole or a similar supporting structure) unduly cumbersome.

The related art includes, under the provisions of Art. 54.3 EPC, EP applications 08168026 and 08168028, filed in the name of the same Applicants.

Object and summary of the invention

In view of the foregoing the need is felt for further improved arrangements capable of providing, i.a.:

- a stable and reliable standard mounting structure, - efficient allowing for tolerances in the parts being assembled, integration of mechanical assembly of parts and operating functions (e.g. thermal, electrical)

- easy assembly/disassembly of the elements comprising the LED light source.

The object of the invention is to provide a response to that need.

According to the present invention, such an object is achieved by means of an arrangement having the features set forth in the claims that follow.

The invention also relates to a corresponding method.

The claims are an integral part of the disclosure of the invention provided herein.

An embodiment of the arrangement described herein is a standardized system including a (e.g. metal) base plate able to provide mechanical fixation for a LED lamp and including buttonholes adapted to co-operate with at least one pushbutton in the LED lamp.

In an embodiment, the interconnection between the mechanical parts also provides electrical connection.

In an embodiment, the base plate carries a Printed Circuit Board (PCB) with sliding contacts adapted to cooperate with spring connectors carried by the LED lamp.

An embodiment of the arrangement described herein thus includes : an integrated LED lamp for mounting in a street lighting pole head system providing mechanical, thermal and electrical connection in a fast-to-assemble, reliable assembly,

- automatic optical centering of the LED lamp,

- a reliable push-button coupling system, - spring screws for system centering/fixing and fast assembly/disassembly.

The arrangement described herein is thus adapted to provide :

- mechanical stability,

- the possibility of easy "head pole" maintenance, a high level of flexibility in assembling /disassembling the LED lamp also after the end-of-life of the LED lamp,

- a coupling system which does not necessitate the use of any specific tools or instruments (e.g. screwdrivers, ...)

Brief description of the annexed views

The invention will now be described, by way of example only, with reference to the enclosed views, wherein:

- Figures 1 to 4 are representative of a sequence of steps in assembling an arrangement as described herein;

- Figures 5 further details the assembly mechanism of the arrangement described herein;

- Figure 6 is a partly broken view showing cretins details of the arrangement described herein;

- Figure 7 shows an alternative embodiment for a first side part of the arrangement described herein;

Figure 8 shows an alternative embodiment for a second side part of the arrangement described herein; and

Figure 9 is a cross section of the completed fixing structure 100 along the plane A-A as indicated in figure 8;

Detailed description of embodiments

In the following description, numerous specific details are given to provide a thorough understanding of embodiments. The embodiments can be practiced without one or more of the specific details, or with other methods, components, materials, etc. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the embodiments .

Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

The headings provided herein are for convenience only and do not interpret the scope or meaning of the embodiments .

The embodiment illustrated in the figures is a reusable fixing structure 100 for a LED lighting module for use e.g. in a street lighting system. The structure is thus adapted for mounting at the head of a pole without re- cabling or screwing.

In the embodiment illustrated herein, the structure 100 includes:

- a thermally conductive (i.e. heat dissipative) base plate 102 adapted to be mounted e.g. at the head of a pole in a street lighting system, and

- a (replaceable) LED lamp 104.

The lamp 104 may include one or more LED lighting sources such as high-power LED lighting sources. In the embodiment illustrated, the lamp 104 includes an array of three LED sources 106. As illustrated, the heat dissipative (e.g. metal) base plate 102 is in the form of a shaped body adapted to be fixed to a support surface (as provided e.g. at the head of a pole) . Fixing may be via screws or by any other means.

In an embodiment, the base plate 102 is incorporated directly to the pole head (i.e. the supporting surface) thus reducing the thermal resistance offered to heat- sinking from the lamp, while further reducing mechanical complexity.

In an embodiment, the base plate 102 has a channel- like shape overall, including:

- a flat web portion 1020 to lie against the mounting support surface, and

- two side portions 1022 to extend upwardly from the web portion 1020.

The side portions 1022 have holes 1024, 1025 (or similar formations) for snap-in engagement of parts of the lamp 104 to be described in the following.

As illustrated, the lamp 104 includes a vat-shaped body with a bottom portion where the LED sources 106 are arranged with respective lenses associated therewith.

Further details of the mounting arrangement of the LED sources and the lenses can be found in the two earlier EP applications by the same applicants already cited in the introductory portion of this description.

The inner surface of the reflector body of the lamp 104 is treated to be reflective (by known means, e.g. by being provided with reflective facets) and shaped (e.g. by having an at least approximately parabolic or paraboloid- like shape) to properly direct the light rays from the LED sources 106 (and especially the "outer" fraction of these light rays possibly escaping the focusing action of the lenses associated with the LEDs) towards the distal opening of the reflector body to be projected from the lamp 104.

The reflective nature of the inner surface of the reflector body of the lamp 104 is exemplified in the view of Figure 3. This gives the impression that more than three LED sources 106 are included in the lamp 104. In fact the "extra" LED sources in Figure 3 are just the three LED sources 106 being reflected by the opposite sides of the reflective inner surface of the reflector body of the lamp 104.

Connection of the lamp 104 with the base plate 102 is by snap-like engagement.

To that effect, in the embodiment shown the body of the lamp 104 carries tooth formations adapted to engage the holes 1024, 1025 in the side portions 1022 of the base plate 102.

In the exemplary embodiment as illustrated, these tooth formations include a set of e.g. three teeth 1068 adapted to engage (see Figure 1) three corresponding holes 1024 in the side portion 1022 of the base plate 102 which is proximate to the LED sources.

Engagement of the teeth 1068 in the holes 1024 creates a sort of hinge-like coupling between the body of the lamp 104 and the base plate 102 (see Figure 2) . The lamp 104 reflector body 106 can thus be rotated in a clamp-like fashion against the base plate 102 (see the sequence of Figures 2 and 3) until a tooth 1070 provided at the opposite side of the body of the lamp 104 engages in a snap-like fashion a corresponding hole 1025 in the opposite side portion 1022 of the base plate 102 (see Figure 4) . As a result of this snap-like engagement, the lamp 104 is securely fixed the base plate 102 (and thus to the pole head) .

In the exemplary embodiment illustrated, the tooth 1070 comprises the distal, hook-like end of an elastically flexible portion 1072 the body of the lamp 104 (e.g. an elastically flexible "tongue" cut into that body) which can be pressed inwardly of the body 104 e.g. by acting on a push-button 1074 provided intermediate the flexible portion 1072. Pressing the portion 1072 inwardly of the body of the lamp 104 will cause the tooth 1070 to become disengageable of the hole 1025, thus permitting the lamp 104 to be rotated away from the plate 102 and disengaged therefrom by the "backward" sequence of Figures 4 to 1.

This will permit e.g. a lamp 104 having completed its useful life to be removed from a pole and replaced with a new lamp.

The same pushbutton-actuated arrangement illustrated in connection with the tooth 1070 can be applied to the teeth 1024, thus making it possible to achieve coupling/decoupling of the lamp 104 to/from the base plate 102 via a rectilinear motion as schematically shown in Figure 4. This with the additional advantage of achieving a self-centering feature of the lamp 104 onto the base plate 102 due to elastically loaded engagement formations being provided on opposite sides of the lamp 104. Such formations being elastically urged in opposite directions thus provides a self-centering action.

Elastic tongue formation 104a can also be provided in the lamp 104 to engage side notches 102a in the base plate 102 to provide or co-operate in providing centering of the lamp 104 over the base plate 102. The presence of three teeth 1024 as illustrated herein will give rise to an arrangement including four pushbutton- actuated teeth 1068, 1070. However a different number of such teeth can be provided so that the arrangement illustrated herein may include e.g. 1, 2, 3 or 4 teeth or similar engagement formations.

Figure 6 shows in greater detail the presence a Printed Circuit Board (PCB) or similar element 1080 carrying electrical connectors 1082 adapted to cooperate with corresponding contacts 1042 carried by the body of the lamp 104. In an embodiment, the connectors 1082/contacts 1042 comprise a spring connector (spring plunger) arrangement providing electrical connection for the LEDs 106 simultaneously with mechanical connection of the lamp 104 to the base plate 102.

In an embodiment, the PCB 1080 is carried by the plate 102 in proximity of the hole 1025 that receives the tooth 1070.

In an embodiment, the PCB 1080 is arranged "vertically" i.e. orthogonal of the web portion 1020 of the plate 102 to facilitate mutual sliding of the connectors 1082 and contacts 1042 into and away from contact as the lamp 104 is mounted to the base plate 102 and removed therefrom, respectively.

In an embodiment, the PCB 1080 is carried by a block 1084 secured to the plate 102 and having e.g. screw connectors 1086 for cabling to feed the LEDs 106.

Figure 7 shows an alternative embodiment mainly for the base plate 102. The design of the shown base plate 702 is similar to the base plate 102 of the previous figures having almost identical features and can be used in the same way but the holes 1024 extend down to the bottom side 703 of the base plate 702 throughout the side portion 1022. This design is favourable for the manufacturing of the base plate 702 because undercuts for the formation of the holes 1024 can be avoided which are cumbersome in a casting process (i.e. die casting or injection moulding) which is a preferred production method for base plates 702.

Figure 8 shows an overview of a base plate 702 as well as a detailed view; this is an alternative embodiment for the second side part 1022 of the base plate 102 as described above. On each side of the side part 102 circular openings 801, 802 are arranged. These openings 801, 802 are used as a housing for a preferably horizontally movable locking device like a ball catch 901 (see figure 9) which is used as a means for fixing the lamp 104 to the base plate 702, i.e. the ball catch is used as an alternative or additional embodiment for the elastic tongue formation 104a shown in figures 1 to 6. Instead of a ball catch a locking bar that is moved inside the openings 801, 802 may also be conceivable .

As can be seen in the cross section A-A in figure 8 the opening 802 on the left hand side of the base plate 702 has a cylinder shape which offers good strength and is easy to manufacture if the base plate 702 is manufactured by machining like e.g. drilling.

On the right hand side of the base plate 702 the opening 801 is formed by three parts 801a, 801b, 801c, the first part 801a being half circular on the top half 8011 and open to the bottom side 703 of the base plate 702. Directly next to this part 801a a second part 801b is half circular in the bottom half 8012 and open to the top side 704 of the base plate 702, whereas the third part 801c is similar to the first part 801a being open to the bottom side 703 of the base plate 702 and having a half circular shape 8013 at the top.

The design of the opening 801 on the right hand side is more favourable in case that the base plate 702 is manufactured by injection molding or casting since this structure can be produced more easily.

Figure 9 is a cross section of the completed fixing structure 100 for a LED lighting module along the plane A-A as indicated in figure 8. The lamp 104 is mounted to the base plate 702. A ball catch 901 is mounted in the opening 802. The ball 902 of the ball catch 901 engages in a shallow cavity 903 of the lamp 104 thereby fixing the lamp 104 to the base plate 702. By acting on the angled surface 904 of the cavity 903 the ball 902 exerts a downward force on the lamp 104, thereby fixing it tightly and with a definite force in its vertical position.

The arrangement of the ball catches 901 on opposite sides of the base plate 702 results in the additional advantage of achieving a self-centering feature of the lamp 104 onto the base plate 702 due to elastically loaded engagement formations being provided on opposite sides of the lamp 104. In combination with the pushbutton-actuated arrangement applied to the teeth 1024 in connection with the tooth 1070, as explained above for figure 4 allows for self-centering action in orthogonal directions thereby centering the lamp 104 perfectly on the base plate 102. The LEDs 106 are placed on a PCB 905 which is held in position by a snap-in hook 906 on each side of the lamp 104 as also displayed in figure 6. Without prejudice to the underlying principles of the invention, the details and the embodiments may vary, even appreciably, with respect to what has been described by way of example only, without departing from the scope of the invention as defined by the annexed claims.

Claims

1. A mounting arrangement (100) for light sources (106) , including:

- a base plate (102, 702) for fixing to a mounting surface,

- a lamp (104) carrying at least one light source (106),

- said base plate (102, 702) and said lamp (104) having : i) complementary mechanical coupling formations (1024, 1068; 1025, 1070; 901, 903) for snap-like coupling said lamp (104) to said base plate (102, 702); and ii) complementary electrical coupling formations (1082, 1042) providing electrical connection for said at least one light source (106) simultaneously with mechanical connection of said lamp (104) to said base plate (102, 702) .

2. The arrangement of Claim 1, wherein said complementary electrical coupling formations (1082, 1042) comprise a spring connector arrangement such as a spring plunger connector arrangement.

3. The arrangement of either of Claims 1 or 2, wherein said base plate (102, 702) carries electrical coupling formations (1082) arranged on a printed circuit board (1080) .

4. The arrangement of Claim 3, wherein said printed circuit board (1080) is arranged orthogonal to said base plate (102, 702) .

5. The arrangement of any of Claims 1 to 4, wherein said base plate (102, 702) carries electrical coupling formations (1082) via a block (1084) having connectors (1086) for cabling to feed said at least one light source (106) .

6. The arrangement of any of Claims 1 to 5, wherein said base plate (102, 702) is incorporated to said mounting surface .

7. The arrangement of any of the preceding claims, wherein said base plate (102, 702) includes:

- a flat web portion (1020), and

- two side portions (1022) extending channel-like from said web portion (1020), wherein said side portions (1022) include at least part of said complementary coupling formations (1024, 1025, 901) with said lamp (104) .

8. The arrangement of Claim 7, wherein said side portions (1022) include openings (1024, 1025, 801, 802) comprising a part of said complementary mechanical coupling formations (1024, 1025, 901) with said lamp (104) .

9. The arrangement of any of the preceding claims, wherein said lamp (104) is provided with teeth (1068, 1070) comprising at least part of said complementary mechanical coupling formations (1024) with said base plate (102, 702) .

10. The arrangement of Claim 9, wherein at least one (1070) of said teeth is resiliently disengageable from a complementary mechanical coupling formation (1025) in said base plate (102, 702) .

11. The arrangement of any of previous claims, wherein said complementary mechanical coupling formations (1024, 1068; 1025, 1070) include:

- at least one set of hinge-like coupling formations

(1024, 1068) to establish a clamp-like coupling between said base plate (102, 702) and said lamp (104), thereby permitting rotation of said lamp (104) against said base plate (102, 702), and - a set of locking formations (1025, 1070) to lock to said base plate (102, 702) said lamp (104) rotated against said base plate (102, 702) .

12. The arrangement of any of the preceding claims, wherein said complementary mechanical coupling formations

(1024, 1068; 1025, 1070) include at least one pushbutton- actuated (1070, 1072, 1074) mechanism to selectively decouple said lamp (104) from said base plate (102, 702) .

13. The arrangement of any of the preceding claims, wherein said complementary mechanical coupling formations

(1024, 1068; 1025, 1070; 901, 903) include elastically loaded coupling formations provided on opposite sides of said lamp (104) said formations elastically urged in opposite directions to provide a self-centering action of said lamp (104) with respect to said base plate.

14. The arrangement of any of the preceding claims, wherein said complementary mechanical coupling formations

(1024, 1068; 1025, 1070; 901, 903) include elastically loaded coupling formations provided on opposite sides of said lamp (104) said formations elastically urged in opposite directions to provide a self-centering action of said lamp (104) with respect to said base plate in at least two different directions, preferably oriented under approximately 90°.

15. The arrangement of any of the preceding claims, wherein at least one of said complementary mechanical coupling formations (1024, 1068; 1025, 1070; 901, 903) exerts a force on the lamp (104) forcing it towards the base plate (102, 702) .

16. The arrangement of any of the preceding claims, wherein said complementary mechanical coupling formations (1024, 1068; 1025, 1070; 901, 903) include at least one ball catch (901) .

17. The arrangement of any of the preceding claims, wherein said at least one ball catch (901) is placed on the base plate (702) .

18. The arrangement of any of the preceding claims, wherein said at least one light source (106) is a LED.

19. The arrangement of any of the preceding claims, wherein the light source is placed on a PCB (905) which is fixed to the lamp by snap-like coupling means (906) .

20. A method of mounting light sources on a mounting surface, including:

- providing a base plate (102, 702) fixed to said mounting surface,

- providing a lamp (104) carrying at least one light source (106) ,

- mechanically and electrically coupling said lamp (104) to said base plate (102, 702) by means of: i) complementary mechanical coupling formations (1024, 1068; 1025, 1070; 901, 903) snap-like coupling said base plate (102, 702) and said lamp (104); and ii) complementary electrical coupling formations (1082, 1042) providing electrical connection for said at least one light source (106) simultaneously with mechanical connection of said lamp (104) to said base plate (102, 702) .