EP3356733B1

EP3356733B1 - Led tubular lamp assembly

Info

Publication number: EP3356733B1
Application number: EP16791450.6A
Authority: EP
Inventors: Vimal Soni
Original assignee: Corvi Led Pvt Ltd
Current assignee: Corvi Led Pvt Ltd
Priority date: 2015-09-29
Filing date: 2016-09-29
Publication date: 2021-11-10
Anticipated expiration: 2036-09-29
Also published as: EP3356733A1; WO2017056110A1

Description

FIELD OF THE INVENTION

The present invention relates to a light emitting diode (LED) tubular lamp assembly according to the preamble of claim 1. Such lamp assemblies are known from EP 2 216 859 A1 . Another lamp assembly is known from US 2013/301255 A1 .

BACKGROUND OF THE INVENTION

The use of LED-chips for lighting applications is currently increasing. Due to their high efficiency and low thermal power in comparison to filament bulbs in particular energy can be saved. Starting with quite specific designs for specific applications, more and more designs become available for use in common and even existing electric lighting installations having standardized bulb sockets such as E22 or E26 or sockets such as T5 or T8 for fluorescent tubes for example. Many of such designs use COB modules (Chip On Board) have LED-chips bonded onto a PCB (Printed Circuit Board). Thereby many chips can be placed on little space, where they collectively create high luminous fluxes, as shown in the closest prior art EP 2 216 859 .

SUMMARY OF THE INVENTION

It is an object of the present invention to provide an LED tubular lamp assembly that can be used in common and even existing tube lighting installations, which is easy to assemble, yet rugged, allows for fully automating the production or at least minimizing manufacturing efforts, and is scalable. These objects are achieved by a LED tubular lamp assembly as defined in the independent claim 1. Preferred embodiments are subject matter of the dependent claims. The inventive LED tubular lamp assembly is characterized in that the tube housing has a flat back wall forming a part of the preferably almost rectangular cross section, the inner notches being partly formed by the flat back wall such that the PCB assembly contacts the flat back wall in a direction perpendicular to the longitudinal direction.
By the invention the following advantages are achieved:
The LED tubular lamp assembly is basically composed of only four main components, namely the tube housing, the PCB assembly and the two side cap assemblies which can be produced independently and effectively assembled in the longitudinal direction by a fully automated process. Just by and upon the at least partial insertion of the side cap assemblies into the tube housing the inner contacts of the side cap assemblies come into electrical contact with the contact areas of the PCB assembly. Hence, additional contact means or even an additional step for establishing contact is not required. The tube housing, due to its constant cross section in a longitudinal direction can be produced in an endless extrusion process, whereby its length defining as well the overall length of the LED tubular lamp assembly can freely be chosen by cutting. In that the cross section of the tube housing is circumferentially closed the tube housing can be made stable and self supporting without need for an additional reinforcement and does not have, aside form its open ends, openings that would have to be sealed.
Preferred embodiments follow from the dependent claims and the description. The individual embodiments may be used independently from or in different combinations with each other, depending on whether a particular advantage of a particular embodiment or combination of embodiments is needed in a specific case.
The two notches can easily be provided by suitably designing the cross section of the tube housing. The two inner notches being engaged with the PCB assembly may in particular fix the PCB assembly in the tube housing and define its position preferably in parallel to the flat back well. The tube housing and PCB assembly so engaged may also mutually further stabilize each other.
The tube housing may have two first outer ribs extending in the longitudinal direction in correspondence with the inner notches, which automatically result if the wall thickness of the tube housing is essentially uniform.
The two outer ribs can be used with advantage for mounting the LED tubular lamp assembly to a supporting structure. For this purpose the LED tubular lamp assembly can further comprise at least one mounting bracket having two snap arms for engaging said first outer ribs and a connecting part between the snap arms.
The flat back wall may be provided with second outer ribs extending in the longitudinal direction. Such ribs could provide additional stiffness to the tube housing and could help to keep the flat back wall in a defined distance from a supporting structure to which the LED tubular lamp assembly may be mounted.
The PCB assembly may be fixed against displacement in the longitudinal direction in the tube housing by the two side cap assemblies. Thereby, such fixation may be achieved without any further means just by the at least partly insertion of the two side cap assemblies into the tube housing.
The contact areas are preferably flat areas located at end sections of the PCB assembly. Such flat areas can be provided at the PCB assembly without additional effort and can easily an effectively be contacted by suitably designed inner contacts of the side cap assemblies as will still be explained in more detail.
Prior art fluorescent tubular lamps are commonly provided with a pair of outer contacts at each end allowing their electrical connection with a starter in series. Though LED-chips do not require a starter, providing pairs of outer contacts would allow the LED tubular lamp assemblies of the invention to be used in even already existing installations with common sockets such as T5 or T8 in replacement of common fluorescent tubular lamps. For allowing the LED tubular lamp assemblies of the invention to be used hereby without regard to their orientation, the inner contacts and the contact areas should be provided pairwise as well. In this case it is possible to have the outer contacts suitably and connected by simple means on the PCB assembly.
LED-chips of the kind as preferably used for the LED tubular lamp assembly according to the invention require low voltage and cannot be directly connected to a mains supply of considerably higher voltage. The avoid the necessity of externally providing voltage converting means in addition the PCB assembly may be provided with electronic devices including at least one integrated circuit for supplying the LED-chips with electric power from a mains supply.
Upon at least partial insertion of the side cap assemblies in the longitudinal direction, the end sections of the tube housing can become wedged, such that a press fit between the substrate and the base is established. Hence, additional fixation means for securing the side cap assemblies in the tube housing may be omitted.
As this is common for many fluorescent tubular lamps the outer contacts of the side cap assemblies may comprise pins projecting outwards in the longitudinal direction. Such pins may be adapted to fit into common sockets such as T5 or T8 in particular. In this case the LED tubular lamp assembly of the present invention can be used in replacement of common fluorescent tubular lamps of even already existing lighting installations.
Generally the same applies to an embodiment of a LED tubular lamp assembly according to the invention wherein the outer contacts of one of the side cap assemblies
are male type outer contacts and wherein the outer contacts of the other end cap assembly are female type outer contacts, the male and female type outer contacts being configured to be connected by plugging in the longitudinal direction, respectively.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will become readily apparent from the following detailed description of the preferred embodiments with reference to the accompanying drawings. In the drawings:

Fig. 1a: is a schematic perspective exploded view of a first embodiment of a LED tubular lamp assembly according to the present in prevention comprising a tube housing, a PCB assembly and two side cap assemblies;
Fig. 1b: is a cross-sectional view of the tube housing shown in fig. 1a;
Fig. 2a: is a schematic top view of the one of the side cap assemblies shown in fig. 1;
Fig. 2b: is a schematic front view of the side cap assembly shown in fig. 2a;
Fig. 2c: is a schematic right view of the side cap assembly shown in figs. 2a and 2b;
Fig. 2d: is a schematic perspective exploded view of the side cap assembly shown in figs. 2a to 2c ;
Fig. 2e: is a cross-sectional view along the cross-sectional line E-E illustrated in fig. 2b;
Fig. 3a: is a schematic top view of the assembly shown in fig. 1 in a fully assembled state;
Fig. 3b: is a schematic front view of the assembly shown in fig. 3a;
Fig. 3c: is a schematic left view of the assembly shown in figs. 3a and 3b;
Fig. 3d: is a schematic right view of the assembly shown in figs.3a to 3c;
Fig. 3e: is a schematic bottom view of the assembly shown in figs.3a to 3d;
Fig. 4a: is a schematic top view of the assembly shown in fig. 1 in a fully assembled state;
Fig. 4b: is a detailed A illustrated in fig.4a;
Fig. 4c: is a cross-sectional view along the cross-sectional line B-B illustrated in fig. 4b;
Fig. 4d: is a detailed A illustrated in fig. 4a;
Fig. 4e: is a cross-sectional view along the cross-sectional line D-D illustrated in fig 4d;
Fig. 5: is a schematic perspective exploded view of a second embodiment of a LED tubular lamp assembly according to the present in prevention comprising a tube housing, a PCB assembly and two side cap assemblies;
Fig. 6a: is a schematic top view of the one of the side cap assemblies shown in fig. 5;
Fig. 6b: is a schematic front view of the side cap assembly shown in fig. 6a;
Fig. 6c: is a schematic right view of the side cap assembly shown in figs. 6a and 6b;
Fig. 6d: is a schematic perspective exploded view of the side cap assembly shown in figs. 6a to 6c;
Fig. 6e: is a cross-sectional view along the cross-sectional line E-E illustrated in fig. 6b;
Fig. 7: is a schematic perspective exploded view of a third embodiment of a LED tubular lamp assembly according to the present in prevention comprising a tube housing, a PCB assembly, one male side cap assembly, one female side cap assembly and two mounting brackets;
Fig. 8a: is a schematic top view of the assembly shown in fig. 7 in a fully assembled state;
Fig. 8b: is a schematic front view of the assembly shown in fig. 8a;
Fig. 8c: is a schematic left view of the assembly shown in figs. 8a and 8b;
Fig. 8d: is a schematic right view of the assembly shown in figs. 8a to 8c;
Fig. 8e: is a schematic bottom view of the assembly shown in figs. 8a to 8d;
Fig. 9a: is a schematic top view of the assembly shown in fig. 7 in a fully assembled state;
Fig. 9b: is a detailed E illustrated in fig. 9a in the region of a mounting bracket;
Fig. 9c: is a cross-sectional view along the cross-sectional line F-F illustrated in fig. 9b;
Fig. 10a: is a schematic top view of the male the side cap assembly shown in fig. 7;
Fig. 10b: is a schematic front view of the male side cap assembly shown in fig. 10a;
Fig. 10c: is a schematic right view of the male side cap assembly shown in figs. 10a and 10b;
Fig. 10d: is a schematic perspective exploded view of the male side cap assembly shown in figs. 10a to 10c;
Fig. 10e: is a cross-sectional view along the cross-sectional line L-L illustrated in fig. 10b;
Fig. 11a: is a schematic top view of the female side cap assembly shown in fig. 7;
Fig. 11b: is a schematic front view of the female side cap assembly shown in fig. 11a;
Fig. 11c: is a schematic right view of the female side cap assembly shown in figs. 11a and 11b;
Fig. 11d: is a schematic perspective exploded view of the female side cap assembly shown in figs. 11a to 11c;
Fig. 11e: is a cross-sectional view along the cross-sectional line K-K illustrated in fig. 11b;
Fig. 12a: is a schematic top view of the LED tubular lamp assembly shown in fig. 7;
Fig. 12b: is a detailed A illustrated in fig. 12a partly showing the female side cap assembly;
Fig. 12c: is a cross-sectional view along the cross-sectional line C-C illustrated in fig. 12b;
Fig. 12d: is a detailed B illustrated in fig. 12a partly showing the male side cap assembly;
Fig. 12e: is a cross-sectional view along the cross-sectional line D-D illustrated in fig. 12d;
Fig. 13a: is a schematic top view of the LED tubular lamp assembly shown in fig. 7;
Fig. 13b: is a detailed G illustrated in fig. 13a partly showing the female side cap assembly;
Fig. 13c: is a cross-sectional view along the cross-sectional line H-H illustrated in fig. 13b
Fig. 13d: is a detailed I illustrated in fig. 13a partly showing the male side cap assembly;
Fig. 13e: is a cross-sectional view along the cross-sectional line J-J illustrated in fig. 13d.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Figures 1 - 4 show a first embodiment of a LED tubular lamp assembly 1 according to the present invention.
In fig 1a the tubular lamp assembly 1 is exploded in a longitudinal direction X which is characterized by a double arrow. Four main components are shown separated from each other but ready to be assembled by relative movement just in the longitudinal direction X as well. The assembly 1 comprises a tube housing 10, a PCB assembly 20 and two side cap assemblies 30. The side cap assemblies 30 are identically designed in this embodiment.
The tube housing 10 has a cross section as shown in fig. 1b which is circumferentially closed and constant in the longitudinal direction X constant. The cross section is almost rectangular with a width W and a height H. The width W is slightly greater than the height H. The length L in the longitudinal direction X is much greater than both, the Width W and the height H. As part of the almost rectangular cross section the tube housing 10 has a flat back wall 11, two slightly curved side walls 12 and a slightly curved front wall 13. The tube housing 10, in particular the front wall 13 is at least partly light-permeable, i.e. transparent or translucent. The back wall does not need to be light-permeable as well. Two inner notches 14 extend in the longitudinal direction X at the side walls 12 adjacent the flat back wall 11. In that the thickness of at least the side walls 12 is almost uniform, two first outer ribs 15 result at the side walls 12 extending in correspondence with the inner notches 14 in the longitudinal direction as well. The flat back wall 11 is further provided with two second outer ribs 16 extending in the longitudinal direction as well.
The PCB assembly 20 comprises a printed circuit board 21 provided with a plurality of LED-chips 22 arranged in a row. The printed circuit board 21 is further provided with electronic devices 23 including at least one integrated circuit for supplying the LED-chips 22 with electric power from a mains supply. At its two end sections 25 the PCB assembly 20 is further provided with a pair of flat contact areas 24, respectively. Other flat contact areas and tracks on the printed circuit board 21 for electrically connecting the LED-chips 22 and the electronic devices 23 are not shown but should be understood as being provided of course, too.
In this first embodiment the two side cap assemblies 30, different views of which are shown in figures 2a - 2e, are identical as already mentioned. Only one of it is described in the following. The side cap assembly 30 is provided with a pair of outer contacts 31 for allowing the LED tubular lamp assembly 1 to be electrically connected to an electric power supply (not shown). The outer contacts 31 are in the form of pins projecting outwards in the longitudinal direction X for being compatible with standard sockets such as T5 in particular. The side cap assembly 30 is further provided with a pair of inner contacts 32 for electrically connecting the outer contacts 31 to the contact areas 24 on the printed circuit board 21. The inner contacts 32 are in the form of spring type sliding contacts. The side cap assembly 30 further has a flat wall part 33 in which the outer contacts 31 and the inner contacts 32 are commonly secured and from which projects a tube like section 34 in the longitudinal direction surrounding the inner contacts 32. The flat wall part 33 extends beyond the tube like section 34 on all sides thereof for forming a collar 35. From the flat wall part 33 further a tongue 36 projects between the inner contacts 32 as a separating means between such contacts. The tongue also guides the contacts upon their deflection.
Different views of the LED tubular lamp assembly 1 of fig. 1a are shown in figures 3a - 3e in the assembled state. Figures 4 a - 4e show details of the LED tubular lamp assembly of Fig. 1a as well in the assembled state. For assembling its four main components, in a first step, the PCB assembly 20 is inserted in the longitudinal direction X into the tube housing 10 such that the printed circuit board 21 engages with its outer edges 21a and 21 b the two notches 14. Thereby the PCB assembly 20 is arranged with only a small lateral tolerance parallel to the flat back wall 11 and even preferably in contact therewith. The PCB assembly is of course inserted into the tube housing 10 in an orientation that the light emitted by the LED-chips 22 is mainly emitted in the direction of the front wall 13.
In a second and third step the two side cap assemblies 30 are as well inserted in the longitudinal direction into the tube housing 10 at both ends thereof. The tube like sections 34 are adapted to closely fit into the tube housing 10 such that the end sections thereof are wedged and a press fit is achieved securing the side cap assemblies 30 in the tube housing 10 without the necessity of further means. By collars 35 becoming flush with the front ends of the tube housing 10 the insertion of the side cap assemblies 30 is restricted to a partial insertion. The outer contours of the collars 35 also conform to the outer contour of the cross section of the tube housing 10.
Upon insertion of the two side- cap assemblies 30 the inner contacts 32 which are in the form of spring type sliding contacts slidably come into electrical contact with the contact areas of the PCB assembly as this can best be seen from figures 3b and 3d. No further means or procedural steps are required to establish such contact.
The length of the printed circuit board 21 of the PCB assembly 20 is chosen such that it fits almost exactly between the two side cap assemblies 30 in the tube housing 10. In the assembled state that is shown in figures 4a - 4d the PCB assembly 20 is thereby fixed against displacement in the longitudinal direction in the tube housing 10 by the two side cap assemblies 30.
Figures 5 and 6 show a second embodiment of a LED tubular lamp assembly 1 according to the present invention. Different from the first embodiment the pins of the first contacts 31 of the side cap assemblies 30 are separated by a greater distance from each other than in the first embodiment. This also applies for the spring type second contacts 32. Thereby contacts 31 are compatible with standard sockets such as T8 in particular.
In the second embodiment the tube like sections 34 of the side cap assemblies 30 are also somewhat different from such sections of the first embodiment as this can be seen by comparing figures 2c - 2e with figures 6c - 6e. There is no tongue like element 36 provided in the second embodiment but cut-outs 37 instead.
A third embodiment will now still be explained with reference to figures 7 - 13. In this embodiment the two side cap assemblies are different from each other. The outer contacts of one of the side cap assemblies, in fig. 7 designated by 30m are male type outer contacts 31m whereas the outer contacts of the other side cap assembly, in fig. 7 designated by 30f, are female type outer contacts 31f. Both, the male 31m and the female type outer contacts 31f are configured to be connected by plugging in the longitudinal direction X.
In contrast, LED tubular lamp assemblies according to the first or and second embodiment of the invention that are provided with projecting pin like outer contacts 31 being compatible with common T5 or T8 sockets are inserted as a whole transversely with respect to their longitudinal extension between two such sockets with their projecting pins 31 engaging a slit in a rotatable part of the sockets, respectively. The LED tubular lamp assemblies and are then electrically connected as well as mechanically secured by rotation around their longitudinal extension. With the male and female type outer contacts 31m and 31f of the third embodiment mechanical fixation means may be required in addition to the pluggable electrical contact means.
Fig. 7 shows the LED tubular lamp assembly according to the third embodiment of the invention together with two mounting brackets 40 as additional mechanical fixation means. The mounting brackets 40 have two snap arms 41 for engaging the first outer ribs 15 of the tube housing 10 and a connecting part 42 between the snap arms each. A screw hole 43 in the connecting part 42 allows an attachment of the mounting brackets 40 by means of a screw and if necessary a wall plug to a supporting structure.
Figures 8a - 8e show the LED tubular lamp assembly of fig. 7 in the assembled state together with two mounting brackets 40 snapped onto the tube housing. More details of the brackets 40 can be taken from figures 9a - 9c.
Different views of the side cap assembly 30m of fig. 7 having male type outer contacts 31 m are shown in figures 10a - 10e. Figures 11a - 11e show different views of the side cap assembly 30f of fig. 7 having female type outer contacts 31f. Figures 12a - 12d and 13a - 13d show details of the LED tubular lamp assembly of Fig. 7 in the assembled state. Apart from the male and female type outer contacts 31 m and 31f the design of the side cap assemblies 30m and 30f of the third embodiment is almost identical and corresponds to the design of the side cap assemblies 30 of the first embodiment. In particular, the inner contacts 32 are again in the form of spring type sliding contacts here and a tube like section 34 is provided surrounding the inner contacts which is adapted to closely fit into the tube housing 10. Both side cap assemblies 30m and 30f are thereby configured to be inserted into the tube housing 10 in the longitudinal direction X and to be secured therein by a press fit.
In all three described embodiments the same tubular housing 10 and the same PCB assembly 20 may be used. To be compatible with the distance of the inner contacts 32 which is different in the first and second embodiment, the contact areas 24 on the printed circuit board 21 are designed large enough to match with the respective positions of the inner contacts 32 in each case.

REFERENCE NUMERALS

1: tubular lamp assembly
10: tube housing
11: flat back wall
12: side walls
13: front wall
14: inner notches
15: first outer ribs
16: second outer ribs
20: PCB assembly
21: printed circuit board
21a,b: outer edges
22: LED-chips
23: electronic devices
24: contact areas
25: end sections
30: side cap assemblies
30m: side cap assembly
30f: side cap assembly
31: outer contacts
31m: male type outer contacts
31f: female type outer contacts
32: inner contacts
33: flat wall part
34: tube like section
35: collar
36: tongue
37: cut-outs
40: mounting brackets
41: snap arms
42: connecting part
43: screw hole
X: longitudinal direction
W: width
H: height
L: length

Claims

LED tubular lamp (1) assembly comprising:
a tube housing (10) being at least partly light-permeable and having a cross section which is circumferentially closed and constant in a longitudinal direction (X);

a PCB assembly (20) provided with contact areas (24) and LED-chips (22) and being inserted in the tube housing (10) in the longitudinal direction (X); and

two side cap assemblies (30; 30m, 30f) provided with outer contacts (31; 31m, 31f) for allowing the LED tubular lamp assembly (1) to be electrically connected to an electric power supply and inner contacts (32) for electrically connecting the outer contacts (31; 31m, 31f) to the contact areas (24) of the PCB assembly (20) and being at least partly inserted in the tube housing (10) in the longitudinal direction (X); and

wherein the inner contacts (32) are configured to slidably come into electrical contact with the contact areas (24) of the PCB assembly (20) upon the at least partial insertion of the side cap assemblies (30; 30m, 30f) into the tube housing (10) in the longitudinal direction (X), wherein the inner contacts (32) of the side cap assemblies (30) are spring type sliding contacts, wherein the spring type sliding contacts are separated from one another and guided upon deflection by a tongue (36) protruding between them, respectively, wherein the outer contacts (31; 31m, 31f) are formed integrally with the inner contacts (32), wherein the tube housing (10) has two inner notches (14) extending in the longitudinal direction (X), facing each other and being engaged by the PCB assembly (20), characterized in that the tube housing (10) has a flat back wall forming a part of the preferably almost rectangular cross section, the inner notches (14) being partly formed by the flat back wall such that the PCB assembly (20) contacts the flat back wall in a direction perpendicular to the longitudinal direction (X).
LED tubular lamp assembly (1) according to claim 1, wherein the tube housing (10) has two first outer ribs (15) extending in the longitudinal direction (X) in correspondence with the inner notches (14).
LED tubular lamp assembly (1) according to claim 2, further comprising at least one mounting bracket (40) having two snap arms (41) for engaging the first outer ribs (15) of the tube housing (10) and a connecting part (42) between the snap arms (41) for an attachment of the LED tubular lamp assembly (1) to a supporting structure.
LED tubular lamp assembly (1) according to one of claims 1 - 3, wherein the tube housing (10) has a flat back wall (11) being provided with second outer ribs (16) extending in the longitudinal direction (X).
LED tubular lamp assembly (1) according to one of claims 1 - 4, wherein the PCB assembly (20) is fixed against displacement in the longitudinal direction (X) in the tube housing (10) by the two side cap assemblies (30; 30m, 30f).
LED tubular lamp assembly (1) according to one of claims 1 - 5, wherein the PCB assembly (20) has end sections (25) with regard to the longitudinal direction and wherein the contact areas (24) are flat areas at such end sections (25).
LED tubular lamp assembly (1) according to one of claims 1 - 6, wherein the contact areas (24), the inner contacts (32) and the outer contacts (31; 31m, 31f) are provided pairwise, respectively.
LED tubular lamp assembly (1) according to one of claims 1 - 7, wherein the PCB assembly (20) is provided with electronic devices (23) including at least one integrated circuit for supplying the LED-chips (22) with electric power from a mains supply.
LED tubular lamp assembly (1) according to one of claims 1 - 8, wherein the side cap assemblies (30; 30m, 30f) are secured to the tube housing (10) by press fit-ting in the longitudinal direction (X).
LED tubular lamp assembly (1) according to one of claims 1-9, wherein the outer contacts (31; 31m, 31f) of the side cap assemblies (30; 30m, 30f) comprise pins projecting outwards in the longitudinal direction (X).
LED tubular lamp assembly (1) according to one of claims 1-9, wherein the outer contacts of one of the side cap assemblies (30m) are male type outer contacts (31m) and wherein the outer contacts of the other side cap assembly (30f) are female type outer contacts (31f), the male and female type outer contacts (31m, 31f) being configured to be connected by plugging in the longitudinal direction (X), respectively.