Powder coating booth

• US 20070062444A1
• Filed: 06/20/2006
• Published: 03/22/2007
• Est. Priority Date: 09/19/2005
• Status: Active Grant

• Current Assignee: Nordson Corporation
• Original Assignee: Nordson Corporation
• Inventors: Schroeder, Joseph, Kreeger, Kenneth, Dailidas, Jeffrey, Shutic, Jeffrey
• Granted Patent: US 7,665,414 B2
• Time in Patent Office: Days
• US Class Current: 118/309
• CPC Class Codes: B05B 12/14 for supplying a selected one of a plurality of liquids or other fluent materials or several in selected proportions to a spray apparatus, e.g. to a single spray outlet
• CPC Class Codes: B05B 13/0405 with reciprocating or oscillating spray heads B05B13/0436, B05B13/0442, B05B13/0447, B05B13/0468 take precedence
• CPC Class Codes: B05B 14/41 by cleaning the walls of the booth
• CPC Class Codes: B05B 14/43 by filtering the air charged with excess material
• CPC Class Codes: B05B 14/45 using cyclone separators
• CPC Class Codes: B05B 14/48 specially adapted for particulate material
• CPC Class Codes: B05B 16/40 Construction elements specially adapted therefor, e.g. floors, walls or ceilings ceiling elements filtering inflow of air into the booth B05B16/60; walls specially adapted for promoting separation of excess material B05B14/44
• CPC Class Codes: B05B 16/90 comprising conveying means for moving objects or other work to be sprayed in and out of the booth, e.g. through the booth
• CPC Class Codes: Y02P 70/10 Greenhouse gas [GHG] capture, material saving, heat recovery or other energy efficient measures, e.g. motor control, characterised by manufacturing processes, e.g. for rolling metal or metal working
• CPC Class Codes: Y10S 55/46 Spray booths

Abstract

A powder spray for lengthy parts includes a booth wall structure comprised primarily of doors. A moveable roof may be raised and lowered to clean powder overspray from the interior surfaces of the booth. A cleaning process may be performed with a sideways extraction mode and a downward extraction mode. The mode change occurs when a bulkhead that travels with the moveable roof blocks the inlet duct to the recovery system. The recovery system may be a cyclone system for example. The doors of the booth are hinged so that they can be positioned for spraying operations and cleaning operations. Live hinge designs are provided and hose stress relief designs are also provided. The roof may carry accumulators for pressurized air that feed cleaning nozzles as the roof descends. In addition, exhaust air may be used to assist cleaning the interior surfaces as the roof descends. All of the energy provided for cleaning and color change may be provided by accumulators.

Claims

1. A spray booth for application of powder coating material to an object, the booth comprising doors with at least one door hinged for movement, said doors substantially comprising the booth wall structure.

2. The spray booth of claim 1 wherein each door comprises two vertically arranged sections.

3. The spray booth of claim 1 comprising pneumatic actuators for moving the doors between open and closed positions.

4. The spray booth of claim 1 comprising a roof having a perimeter that generally conforms to the shape of the booth when the doors are closed.

5. The spray booth of claim 4 wherein said roof is generally diamond shaped in plan view.

6. The spray booth of claim 1 comprising a roof that is raised and lowered within the booth interior during a powder removal operation.

7. The spray booth of claim 6 wherein said roof carries a plurality of air nozzles for removing powder off of interior surfaces of said doors.

8. The spray booth of claim 7 comprising a reservoir for pressurized air carried by said roof to provide pressurized air to said nozzles.

9. The spray booth of claim 1 wherein one or more of said doors comprises air nozzles along a lower end thereof to remove powder from the booth floor.

10. The spray booth of claim 1 comprising a vertically extending intake slot through which powder is extracted from the booth interior.

11. The spray booth of claim 10 wherein said intake slot has a first width near the center of the booth and tapers to a second width at the top and bottom of the booth.

12. The spray booth of claim 11 wherein said intake slot communicates with an inlet duct of a cyclone.

13. The spray booth of claim 12 comprising a roof that is raised and lowered within the booth interior, and a member that travels at about the same speed and position within an extraction duct that is connected to the cyclone inlet duct.

14. The spray booth of claim 13 wherein said extraction duct comprises a tangential inlet.

15. The spray booth of claim 13 wherein powder overspray enters said extraction duct through a floor slot.

16. The spray booth of claim 15 comprising a floor having an opening therein that communicates with the extraction duct, and a cover that can selectively open and close said floor opening.

17. The spray booth of claim 16 wherein as the roof is lowered during a cleaning operation, powder initially is extracted from the booth through said intake slot, said member closing off the inlet duct to the cyclone when the roof reaches a predetermined height within the booth, said floor opening being opened to extract powder through the floor and into a bypass duct or the cyclone as the roof continues to lower to near the floor.

22. The spray booth of claim 1 wherein the booth has a vertical height that is at least about two times greater than its length.

18. A powder spray booth comprising a wall structure and a gun slot formed in said wall, and a gun slot cover to selectively open and close the gun slot;

said gun slot cover comprising a flexible sheet of material that flexes between a first position to open the gun slot and a second position to close the gun slot.

19. The spray booth of claim 18 comprising an actuator to selectively bend the cover.

20. The spray booth of claim 19 wherein said actuator comprises a pneumatic cylinder and piston.

21. The spray booth of claim 20 wherein said cover comprises polypropylene.

23. A method for extracting powder overspray from a powder spray booth, comprising:

lowering a roof from the top of the booth to near the bottom of the booth;

applying pressurized air to remove powder off of interior surfaces of the booth as the roof is lowered;

extracting powder sideways from the booth relative to the vertical axis of the booth during a first portion of movement of the roof, and extracting powder downward through the booth floor during a second portion of movement of the roof.

24. The method of claim 23 comprising the step of extracting powder into a cyclone inlet during said first portion and extracting powder into a bypass duct during said second portion.

25. The method of claim 24 comprising the step of blocking the inlet to the cyclone as the roof reaches a predetermined vertical position within the booth.

26. A powder spray booth, comprising:

a vertical wall with a vertically extending opening therein, a roof that raises and lowers within the booth interior during a cleaning operation, a vertical duct that communicates with said slot and an inlet to a cyclone, and a member that travels with the roof for a portion of the travel of the roof, said member blocking the cyclone inlet at a predetermined vertical position of the roof.

27. The powder spray booth of claim 26 comprising a booth floor having an opening for extracting powder from the booth interior after the roof has reached said predetermined vertical position.

28. In a spray booth of the type having one or more gun slots, a gun slot cover having a first position that opens the gun slots and a second position that covers the gun slots for a cleaning operation.

29. The booth of claim 28 wherein said gun slot cover is pneumatically driven.

30. A method for cleaning a powder spray booth comprising:

drawing exhaust air into the booth through a gap between a roof and surfaces being cleaned Such that the exhaust air removes powder from said surfaces, and applying pressurized air against said surfaces.

31. The method of claim 30 comprising the step of moving the roof during a cleaning operation.

32. The method of claim 30 wherein said pressurized air is intermittently triggered to apply pressure waves against said surfaces.

33. A material application system comprising:

a first set of one or more material application devices supported on a first mover;

a second set of one or more material application devices supported on a second mover;

said first and second movers being vertically arranged with respect to each other.

34. The system of claim 33 wherein each said mover operates to move its respective set of devices in either or both vertical and horizontal directions.

35. The system of claim 33 wherein said movers comprise at least one oscillator.

36. The system of claim 33 comprising more than two movers vertically arranged with respect to each other.

37. The system of claim 33 wherein first and second movers are vertically arranged one above the other and each mover can move its respective set of devices in either or both horizontal and vertical directions.

38. A material application system, comprising:

a spray booth;

a first set of one or more material application devices;

a second set of one or more material application devices;

said first set of material application devices being supported on a first mover that can operate to move said devices horizontally and/or vertically;

said second set of material application devices being supported on a second mover that can operate that can operate to move said devices horizontally and/or vertically;

said first and second movers being vertically arranged with respect to each other.

39. The system of claim 38 wherein said application devices comprise powder spray guns.

40. The system of claim 38 wherein said first and second set each comprise a plurality of devices.

41. The system of claim 38 wherein each mover comprises a gun mover that extends and retracts said devices supported thereon into and out of the spray booth.

42. The system of claim 38 wherein at least one of said first and second movers comprises an oscillator.

43. The system of claim 38 wherein said first and second movers are vertically positioned one above the other.

44. The system of claim 38 wherein said movers are supported on a framework positioned outside the spray booth.