received by the International Bureau on 23 May 2019 (23.05.19)

CLAIMS

1. A display panel:

- a back plate (2);

- a transparent front cover (3);

- an edge gasket (4) interposed between the back plate (2) and the front cover (3);

- an array of LED display tiles (6) supported on the back plate (2);

- a frame (5) surrounding the front cover (3) is engaged with the back plate (2) in such a way that the frame acts to clamp the edge gasket (4) between the front cover and the back plate;

characterised in that

the edge gasket (4) is substantially U-shaped with a pair of spaced legs (33) and (34) connected by a cross piece (35).

2. A display panel according to Claim 1 in which the frame (5) has a front limb (30) which overlies the edge of the front cover (3).

3. A display panel according to Claim 1 in which the frame (5) is provided with fastening elements (38) which are engaged with the back plate (2).

4. A display panel according to Claim 3 in which the fastening elements (38) are inserted through the front cover (3).

5. A display panel according to Claim 3 in which the fastening elements (38) are inserted through the edge gasket (4).

6. A display panel according to Claim 1 in which the frame (5) is provided with fastening elements (38) which are inserted through the cross piece (35) of the edge gasket passing between the legs (33) and (34).

7. A display panel according to Claim 1 in which fixings (36) are inserted through the back plate (2) between the legs (33) and (34) of the edge gasket.

8. A display panel according to Claim 1 in which the edge gasket (4) is provided with sealing ribs (40) which are compressed against the front cover (3) and the back plate (2).

9. A display panel according to Claim 1 in which the frame (5) is substantially of L-section with a front limb (30) which overlies the edge of the front cover (3) and a side limb (31) which covers the edge gasket (4).

10. A display panel according to Claim 1 in which mutually spaced elongate tile guides (7a-7d) are secured to the back plate (2) for mounting the tiles (6) in rows.

11. A display panel according to Claim 10 in which an elongate power backplane (8) is secured to the back plate (2) between each pair of tile guides (7a-7d).

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12. A display panel according to Claim 11 in which each power backplane (8) is located between the tiles (6) and the back plate (2).

13. A display panel according to Claim 11 in which the back plate (2) has a power entry aperture (9a-9c) opposed to each power backplane (8).

14. A display panel according to Claim 11 in which the back plate (2) has data entry apertures (1 la-1 If) between the power backplanes (8) and the tile guides (7a-7d).

15. A display panel according to Claim 10 in which the tile guides (7a-7d) locate opposite edges of the tiles (6) in such a way that the tiles can move away from the tile guides whilst still being accurately held in a fixed relationship to the adjacent tiles in a direction parallel to the back plate (2).

16. A display panel according to Claim 15 in which the tiles

(6) have bosses (23) that locate in holes (24) in the tile guides

(7a-7d).

17. A display panel according to Claim 15 in which the tiles

(6) include magnets (25) to hold the tiles (6) to the tile guides

(7a-7d).

18. A display panel according to Claim 1 in which each tile (6) has a front face (20) which carries an array of LEDs and a rear

23 surface (21) which carries electronic control and power supply circuitry for the tile.

19. A display panel according to Claim 18 in which the electronic circuitry is covered by a moulding (22).

20. A display panel according to Claim 18 in which each tile (6) incorporates a DC voltage converter (50).

21. A display panel according to Claim 18 in which each tile (6) includes on-board diagnostic circuitry (52).

22. A display panel according to Claim 21 in which the diagnostic circuitry (52) monitors one or more of the tile's input voltage, DC converter output voltages, LED current, and tile operating temperature.

23. A display panel according to Claim 21 in which the diagnostic circuitry (52) is arranged to send diagnostic information to an interlock controller (53).

24. A display panel according to Claim 23 in which the interlock controller (53) uses the diagnostic information to reboot the display panel in the event of a problem.

25. A display panel according to Claim 23 in which the interlock controller (53) uses the diagnostic information to shut down the display panel in the event of a persistent problem.

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26. A display panel according to Claim 23 in which the interlock controller (53) is arranged to shut down the display panel by means of a power circuit breaker.

27. A display panel which includes a back plate (2) and an array of LED display tiles (6) supported in rows by mutually spaced elongate tile guides (7a-7d) secured to the back plate, in which the tile guides (7a-7d) locate opposite edges of the tiles (6) in such a way that the tiles can move away from the tile guides whilst still being accurately held in a fixed relationship to the adjacent tiles in a direction parallel to the back plate (2).

28. A display panel according to Claim 27 in which the tiles (6) have bosses (23) that locate in holes (24) in the tile guides (7a-7d).

29. A display panel according to Claim 27 in which the tiles (6) include magnets (25) to hold the tiles (6) to the tile guides (7a-7d).

30. A display panel which includes an array of LED display tiles (6), in which each tile (6) has a front face (20) which carries an array of LEDs and a rear surface (21) which carries electronic control and power supply circuitry for the tile.

31. A display panel according to Claim 30 in which each tile (6) incorporates a DC voltage converter (50).

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32. A display panel according to Claim 30 in which each tile (6) includes on-board diagnostic circuitry (52).

33. A display panel according to Claim 32 in which the diagnostic circuitry (52) monitors one or more of the tile's input voltage, DC converter output voltages, LED current, and tile operating temperature.

34. A display panel according to Claim 32 in which the diagnostic circuitry (52) is arranged to send diagnostic information to an interlock controller (53).

35. A display panel according to Claim 34 in which the interlock controller (53) uses the diagnostic information to reboot the display panel in the event of a problem.

36. A display panel according to Claim 34 in which the interlock controller (53) uses the diagnostic information to shut down the display panel in the event of a persistent problem.

37. A display panel according to Claim 34 in which the interlock controller (53) is arranged to shut down the display panel by means of a power circuit breaker.

38. A display panel according to Claim 30 in which power is supplied to the LED display tiles (6) by a power backplane (8) secured to a back plate (2).

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39. A display panel according to Claim 38 in which the power backplane (8) is located between the tiles (6) and the back plate (2).

40. A display panel according to Claim 38 in which the back plate (2) has a power entry aperture (9a-9c) opposed to the power backplane (8).

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