METHOD FOR PROCESS DIAGNOSIS AND ROTARY ATOMIZER ARRANGEMENT

• US 20100211205A1
• Filed: 07/11/2008
• Published: 08/19/2010
• Est. Priority Date: 07/20/2007
• Status: Active Grant

• Current Assignee: Duerr Systems GmbH
• Original Assignee: Duerr Systems GmbH
• Inventors: Frey, Marcus, Herre, Frank, Haas, Juergen, Meissner, Alexander, Baumann, Michael, Nolte, Hans-Jurgen, Seiz, Bernhard, Block, Torsten
• Granted Patent: US 9,016,596 B2
• Time in Patent Office: Days
• US Class Current: 700/109
• CPC Class Codes: B05B 12/08 responsive to condition of liquid or other fluent material to be discharged, of ambient medium or of target ; responsive to condition of spray devices or of supply means, e.g. pipes, pumps or their drive means
• CPC Class Codes: B05B 15/14 Arrangements for preventing or controlling structural damage to spraying apparatus or its outlets, e.g. for breaking at desired places; Arrangements for handling or replacing damaged parts
• CPC Class Codes: B05B 5/0415 Driving means; Parts thereof, e.g. turbine, shaft, bearings
• CPC Class Codes: B05B 5/0422 comprising means for controlling speed of rotation
• CPC Class Codes: H02P 29/10 for preventing overspeed or under speed

Abstract

A rotary atomizer arrangement and methods for operating the same are disclosed. An exemplary atomizer may be used for the coating of work pieces, and may include a bell plate driven by an electric motor. The exemplary atomizer may further be configured for the detection of errors in the spraying process and/or the drive system of the bell plate, such as by analyzing corresponding parameters of typical values of the drive motor.

Claims

1. A method for process diagnosis during coating of workpieces with a rotary atomizer comprising a rotating spraying element, driven by a drive system comprising an electric drive motor with an adjustable rotary speed, wherein faults are detected, comprising:

driving the spraying element with the electric drive motor, the electric drive motor in communication with an automatic control system; and

evaluating at least one characteristic value of the electric drive motor;

wherein said evaluating includes analyzing at least one process parameter of the drive system of the spraying element, the at least one process parameter relevant to the at least one characteristic value of the drive motor.

18. The method according to claim 1, wherein the electric drive motor is closed-loop controlled.

19. The method according to claim 1, wherein the electric drive motor is open-loop controlled.

20. The method according to claim 1, wherein the process parameter is a parameter of the spraying procedure.

21. The method according to claim 1, wherein the process parameter is a parameter of the drive system.

22. The method according to claim 1, wherein the characteristic value of the electric drive system is selected from a group consisting of:

a magnitude of an electric current flowing through the electric drive motor,

a pattern of an electric current flowing through the electric drive motor,

an electrical power of the electric drive motor,

a torque of the electric drive motor,

a load torque of the electric drive motor,

an acceleration of the electric motor,

a rotary speed of the electric drive motor.

23. The method according to claim 1, wherein the process parameter is a mechanical loading of the drive system by at least one of the spraying element, the coating material, imbalance in the rotating elements, and the mounting of a drive shaft.

24. The method according to claim 1, wherein

a) the process parameter is a volume flow rate of the coating material, and

b) the characteristic value of the electric drive motor is an accelerating behavior of the electric drive motor.

25. The method according to claim 1, wherein the process parameter is a property of the coating material and the characteristic value of the electric drive motor is selected from a group consisting of:

electrical characteristic values,

torque, and

rotary speed of the electric drive motor.

26. The method according to claim 1, wherein

a) the process parameter is a bearing air flowing through an air bearing of the drive shaft of the drive system, and

b) the characteristic value of the electric drive motor is selected from a group consisting of:

a magnitude of the torque,

a pattern of the torque over time,

a rotary speed of the electric drive motor.

27. The method according to claim 1, wherein the process parameter is selected from a group consisting of:

a presence of the spraying element, a moment of inertia of the spraying element, a material of the spraying element, and a type of the spraying element.

28. The method according to claim 1, wherein the at least one characteristic value of the drive motor is evaluated by the automatic control system.

29. The method according to claim 1, wherein the at least one process parameter comprises the switching times of a valve controlling an outflow of the coating material from the rotary atomizer.

30. The method according to claim 1, wherein the evaluation of the characteristic value of the electric drive motor encompasses a determination of at least one of the following parameters:

a negative slope of the characteristic value of the electric drive motor, and

a positive slope of the characteristic value of the electric drive motor.

31. The method according to claim 29, wherein, the switching times determined by the automatic control system of the electric drive motor are compared with target times predetermined by the process control system.

32. The method according to claim 1, wherein a fault detected by evaluating the characteristic value of the electric drive motor is corrected when said fault exceeds a limit value.

33. The method according to claim 1, wherein at least one parameter which is present during at least one of a coating operation, a spraying procedure, rotation of the spraying element at a rotary speed at which the spraying element rotates during a coating operation, and analyzing a spraying procedure by evaluating the at least one characteristic value of the drive motor.

34. The method according to claim 1, wherein the rotary speed of the spraying element at which the analysis of the at least one parameter is carried out is more than 3,000 RPM.

35. The method according to claim 1, wherein the rotary speed of the spraying element at which the analysis of the at least one parameter is carried out is more than 10,000 RPM.

36. The method according to claim 1, wherein the rotary speed of the spraying element at which the analysis of the at least one parameter is carried out is more than 15,000 RPM.

37. The method according to claim 1, wherein the spraying element is at an elevated electrical potential during the analysis of the at least one parameter.

2-17. -17. (canceled)

38. A rotary atomizer arrangement for coating workpieces, comprising

a rotatably mounted spraying element for the coating material,

an electric drive motor configured to drive the spraying element,

an automatic control system configured to control the electric drive motor, and

an electronic evaluating apparatus, with which at least one characteristic value of the electric drive motor can be evaluated in order to analyze at least one process parameter.

39. The rotary atomizer arrangement according to claim 38, wherein the characteristic value of the electric drive motor is selected from a group consisting of:

a size of an electric current of the electric drive motor,

a pattern of the electric current of the electric drive motor,

an electric power of the electric drive motor,

a torque of the electric drive motor,

an acceleration of the electric drive motor, and

a rotary speed of the electric drive motor.

40. The rotary atomizer arrangement according to claim 38, wherein the characteristic value of the electric drive motor is a load on the electric drive motor due at least in part to at least one of the spraying element, the coating material, an imbalance in the rotating elements, and a mounting of the drive shaft.

41. The rotary atomizer arrangement according to claim 38, wherein the electronic evaluating apparatus includes an electronic processor.

42. The rotary atomizer arrangement according to claim 38, wherein the process parameter is a volume flow rate of the coating material, and the characteristic value of the electric drive motor is an acceleration of the electric drive motor.

43. The rotary atomizer arrangement according to claim 38, wherein the process parameter represents a property of the coating material, and the characteristic value of the electric drive motor is selected from a group consisting of a torque and a rotary speed of the electric drive motor.

44. The rotary atomizer arrangement according to claim 38, wherein the process parameter is a bearing air flowing through an air bearing of a drive shaft.

45. The rotary atomizer arrangement according to claim 38, wherein the process parameter is selected from a group consisting of a presence of the spraying element, a moment of inertia of the spraying element, a material of the spraying element, and a type of the spraying element.

46. The rotary atomizer arrangement according to claim 38, wherein the at least one process parameter represents switching times of a valve controlling an outflow of the coating material from the rotary atomizer.

47. The rotary atomizer arrangement according to claim 46, wherein the switching times determined by the automatic control system of the electric drive motor are compared with target times predetermined by the automatic control system.

48. The rotary atomizer arrangement according to claim 38, wherein a fault detected by the evaluation of the characteristic value of the electric drive motor is corrected when said fault exceeds a limit value.

49. The rotary atomizer arrangement according to claim 38, wherein a transformer arrangement is provided having an electrical insulating device between primary and secondary circuits of said transformer arrangement.

50. The rotary atomizer arrangement according to claim 38, wherein signals from at least one of the electronic evaluating apparatus and the automatic control system of the electric drive motor are galvanically separated between a first region at an elevated electrical potential and a second region at a ground potential.