Method of monitoring parameters of coating material dispensing systems and processes by analysis of swirl pattern dynamics

• US 5,322,706 A
• Filed: 11/23/1992
• Issued: 06/21/1994
• Est. Priority Date: 10/19/1990
• Status: Expired due to Fees

• Current Assignee: Kevin C. Becker, Scott Robertson Miller, Stephen L. Merkel
• Original Assignee: Kevin C. Becker, Scott Robertson Miller, Stephen L. Merkel
• Inventors: Miller, Scott R., Merkel, Stephen L., Becker, Kevin C.
• Primary Examiner(s): Beck, Shrive
• Assistant Examiner(s): Utech, Benjamin L.
• Application Number:
  US07/980,422
• Time in Patent Office: 575 Days
• Field of Search: 427/8, 427/10, 427/422, 427/421, 239/67, 239/71
• US Class Current: 427/8
• 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 12/082 responsive to a condition of the discharged jet or spray, e.g. to jet shape, spray pattern or droplet size
• CPC Class Codes: B05C 11/1007 responsive to condition of liquid or other fluent material B05C11/1005 takes precedence
• CPC Class Codes: B05C 11/1013 responsive to flow or pressure of liquid or other fluent material B05C11/101 takes precedence; control of flow in general G05D7/00; control of fluid pressure in general G05D16/00
• CPC Class Codes: B05C 11/1015 responsive to a conditions of ambient medium or target, e.g. humidity, temperature B05C11/1005 takes precedence; responsive to position or movement of the coating head relative to the target
• CPC Class Codes: B05C 11/1023 responsive to velocity of target, e.g. to web advancement rate
• CPC Class Codes: B05C 5/0245 for applying liquid or other fluent material to a moving work of indefinite length, e.g. to a moving web B05C5/0241, B05C5/0254, B05C5/027, B05C5/0283 take precedence

Abstract

A method of monitoring and/or controlling the motion of a moving coating material dispensing pattern or fiber is provided with a monitor that senses a medium such as sound, light or other form of energy near the space between the dispensing device nozzle and a substrate, and a monitoring signal is generated. Information relating to the pattern motion is extracted, and an output signal is generated representative of characteristics of the motion of the pattern in the space. One or more transducers are used to extract the information, which is analyzed, preferably by comparison of a frequency spectrum of the signal with a spectrum of standard signal, to detect deviations in the system operation from desired criteria. Optionally, the output signal is used to control parameters of the system. In another embodiment, plural spaced transducers detect the phase or orientation of the moving pattern and remove background noise, by inverting, summing, multiplying, and otherwise combining the signals. The invention is useful for detecting malfunctions of the system components, for real-time closed loop control of the process, and for quality control inspection of dispensing device components during manufacture.

Claims

1. A method of monitoring the performance of a controlled fiberization device for dispensing a continuous fiber of liquid coating material distributed through a space between the dispensing device and a substrate in a continuous helical pattern which changes position with time by a rotating motion in the space, said method comprising the steps of:

sensing the rotating motion of the pattern of the material in the space between the dispensing device and the substrate; and

generating in response to the sensed motion a signal representative of characteristics of the motion of the pattern in the space.

2. The method of claim 1 wherein the motion is sensed from a plurality of different angular positions around the pattern.

3. The method of claim 2 wherein:

the sensing step includes the step of positioning, at different angular positions about the pattern, a plurality of transducers and sensing therewith information of the motion of the pattern, including phase information related to the angular position of the pattern; and

further comprising the step of combining the phase information from the plurality of transducers to resolve the angular characteristics of the pattern.

4. The method of claim 2 wherein the sensing step includes the step of:

positioning transducers adjacent the pattern, each transducer being capable of sensing information of the motion of the pattern.

5. The method of claim 1 wherein the sensing step includes the step of:

positioning adjacent the pattern at least two transducers and sensing therewith information of the rotating motion of the pattern; and

the generating step includes generating with each transducer a signal in response to the information sensed by the transducer.

6. The method of claim 5 further comprising the steps of:

generating from said transducer signals a first output signal having an enhanced signal-to-noise ratio;

generating from said transducer signals a second output signal;

analyzing the output signals to discriminate between the information of the motion of the pattern and noise; and

analyzing the output signals to determine the motion of the pattern.

7. The method of claim 5 further comprising the steps of:

inverting the signal from one said transducer and adding the inverted signal to the signal from the other transducer to produce an output signal.

8. The method of claim 7 further comprising the step of:

multiplying the inverted signal by the signal from the other transducer to generate a product signal; and

correlating the product and output signals to discriminate between information of the motion of the pattern and noise.

9. The method of claim 1 wherein the sensed motion includes the sensing of a medium selected from the group consisting of:

electromagnetic radiation, sound, and light modulated by the motion of the pattern in the space.

10. The method of claim 1 further comprising the steps of:

repeating said sensing step;

performing a measurement of a characteristic of the signal generated in each generating step;

comparing the measurement so performed; and

producing an output in response to the measurement comparing step.

11. A method of controlling the dispensing of a continuous fiber of liquid coating material distributed in a space between a dispensing device and a substrate to form a pattern in the space, said method comprising the steps of;

ejecting liquid coating material from a dispensing device toward a substrate in a continuous fiber extending through a space located between the dispensing device and the substrate while causing the fiber to change position in the space with time;

sensing motion of the pattern due to the time changing position of the fiber of the material in the space between the dispensing device and the substrate;

generating in response to the information a signal representative of characteristics of the motion of the pattern in the space; and

controlling the ejection in response to said signal.

12. The method of claim 11 further comprising the steps of:

performing a measurement of at least one of the characteristics when the system is operating under conditions to be monitored; and

comparing the measurement with stored reference characteristics; and

the signal generating step includes the step of generating the signal in response to the comparing step.

13. The method of claim 12 wherein:

the measurement performing step includes the step of generating a frequency spectrum of the signal; and

the characteristic includes at least one characteristic selected from the group consisting of;

primary frequency mode of the signal, harmonics thereof, and amplitude of the primary mode of the signal.

14. The method of claim 12 wherein the material is ejected from the dispensing device and subjected to streams of air emitted from jets, and wherein:

the stored reference characteristics include characteristics stored by performing a measurement of at least one of the characteristics when the system is operating with at least one of the jets obstructed.

15. The method of claim 11 wherein the coating material is dispensed under pressure from the dispensing device, and wherein the controlling step comprises the steps of:

comparing the signal representative of the characteristics of the motion of the pattern with stored reference characteristics; and

varying the pressure of the material ejected from the dispensing device in response to said comparison.

16. The method of claim 11 wherein the dispensed coating material is subjected to streams of air emitted under pressure from jets, and wherein the controlling step comprises the steps of:

comparing the signal representative of the characteristics of the motion of the pattern with stored reference characteristics; and

varying the pressure of the air emitted from the jets.

17. The method of claim 11 wherein:

the controlling step includes the step of stopping a function of the dispensing device.

18. The method of claim 11 wherein the sensing step includes the step of sensing energy selected from the group consisting of electromagnetic radiation, sound, and light modulated by the motion of the pattern in the space.

19. The method of claim 11 further comprising the steps of:

performing a measurement of at least one of the characteristics when the system is operating under conditions to be monitored;

comparing the measurement with reference characteristics; and

the signal generating step includes the step of generating the signal in response to the comparing step.

20. The method of claim 11 further comprising the steps of:

repeating said sensing and generating steps;

performing a measurement of a characteristic of the signal generated in each generating step;

comparing the measurements; and

producing an output in response to the comparison.

21. A method of dispensing liquid coating material onto a substrate that moves past the dispensing device at a speed which may vary, said method comprising the steps of:

ejecting coating material at a controlled rate from a dispensing device toward a substrate through a space located between the dispensing device and the substrate, the ejected material being distributed in the space so as to form a pattern in the space which moves such that the distribution of material in the space changes position therein as a function of time;

sensing the time changing position of the pattern of the material in the space between the dispensing device and the substrate and generating a feedback signal responsive to the sensed change of position of the pattern;

generating a speed signal in response to the speed of the substrate past the dispensing device; and

,

varying the rate at which the coating material is ejected from the dispensing device in response to the speed signal and feedback signal so as to vary the rate at which the material is ejected in relation to the speed of the substrate past the dispensing device.

22. The method of claim 21 wherein:

the sensing step includes the steps of sensing information correlated to the time varying change of position of the pattern of material in the space between the dispensing device and the substrate, and generating the feedback signal from the information;

generating a reference signal in response to the speed signal;

comparing the feedback signal with the reference signal; and

varying said rate of ejection in response to the comparison.

23. The method of claim 22 wherein:

the sensing step includes the step of sensing sound produced by the motion of the pattern and the information correlated to the motion of the pattern is the frequency of the sound.

24. A method of monitoring the performance of a dispensing device for dispensing a coating material in a flowable state through a space between the dispensing device and a substrate in a distribution that forms a continuous rotating pattern in the space that changes position in the space with time so as to modulate energy propagating in the space with information of the time varying change in the position of the distribution of material in the space, said method comprising the steps of:

sensing the information of the time varying change of the position of the rotating pattern of the material from the propagating energy in the space between the dispensing device and the substrate; and

generating in response to the information a signal representative of characteristics of the changing position of the rotating pattern in the space.

25. A method according to claim 24 further comprising the steps of:

ejecting coating material from a nozzle toward a substrate through a space located between the nozzle and the substrate along a path that changes position with time; and

controlling the ejection in response to said signal.

26. The method of claim 24 wherein the energy is selected from the group consisting of electromagnetic radiation, sound, and light modulated by the motion of the pattern that changes position as a function of time in the space.

27. A method of monitoring the performance of a dispensing device for dispensing a coating material in a flowable state through a space between the dispensing device and a substrate in a distribution that forms a continuous rotating pattern in the space that changes position in the space with time so as to modulate energy propagating in the space with information of the time varying change in the position of the distribution of material in the space, said method comprising the steps of:

sensing the information of the time varying change of the position of the rotating pattern of the material from the propagating energy in the space between the dispensing device and the substrate;

generating in response to the information a signal representative of characteristics of the changing position of the rotating pattern in the space;

dispensing coating material onto the substrate, where the substrate moves past the dispensing device at a speed which may vary, wherein;

the ejecting of coating material is at a controlled rate from the dispensing device toward a substrate through a space located between the dispensing device and the substrate so as to cause the material to form a moving rotating pattern as it moves along a path that changes position as a function of time; and

the method further comprises the steps of sensing the rotating motion of the pattern of the material in the space between the dispensing device and the substrate and generating a feedback signal responsive to the sensed change of position of the pattern, generating a speed signal in response to the speed of the substrate past the dispensing device, and, varying the rate at which the coating material is ejected from the dispensing device in response to the speed signal and feedback signal so as to vary the rate at which the material is ejected in relation to the speed of the substrate past the dispensing device.

28. A method of monitoring the performance of a dispensing device for dispensing a coating material in a flowable state through a space between the dispensing device and a substrate in a distribution that forms a continuous rotating pattern in the space that changes position in the space with time so as to modulate energy propagating in the space with information of the time varying change in the position of the distribution of material in the space, said method comprising the steps of:

sensing the information of the time varying change of the position of the rotating pattern of the material from the propagating energy in the space between the dispensing device and the substrate;

generating in response to the information a signal representative of characteristics of the changing position of the rotating pattern in the space;

the coating material being dispensed under pressure from the dispensing device, and the controlling step comprising the steps of;

comparing the signal representative of the characteristics of the rotating motion of the pattern with stored reference characteristics; and

the controlling step includes the step of varying the pressure of the material ejected from the dispensing device in response to said comparing step.

29. A method of monitoring the performance of a dispensing device for dispensing a coating material in a flowable state through a space between the dispensing device and a substrate in a distribution that forms a continuous rotating pattern in the space that changes position in the space with time so as to modulate energy propagating in the space with information of the time varying change in the position of the distribution of material in the space, said method comprising the steps of:

sensing the information of the time varying change of the position of the rotating pattern of the material from the propagating energy in the space between the dispensing device and the substrate;

generating in response to the information a signal representative of characteristics of the changing position of the rotating pattern in the space;

the dispensed coating material being subjected to streams of air emitted under pressure from jets; and

the controlling step including the step of comparing a signal representative of the characteristics of the motion of the rotating pattern with stored criteria and, in response the comparing step, varying the pressure of the air emitted from the jets.

30. A method of monitoring the performance of a dispensing device for dispensing a coating material in a flowable state through a space between the dispensing device and a substrate in a distribution that forms a continuous rotating pattern in the space that changes position in the space with time so as to modulate energy propagating in the space with information of the time varying change in the position of the distribution of material in the space, said method comprising the steps of:

sensing the information of the time varying change of the position of the rotating pattern of the material from the propagating energy in the space between the dispensing device and the substrate;

generating in response to the information a signal representative of characteristics of the changing position of the rotating pattern in the space; and

the information being sensed from a plurality of different angular positions around the pattern.

31. The method of claim 30 wherein:

the sensing step includes the step of positioning, at different angular positions about the pattern, a plurality of transducers and sensing therewith the propagating energy;

the information of the motion of the pattern includes phase information related to the angular position of the pattern; and

the method further comprises the step of combining the phase information from the plurality of transducers so as to resolve the angular characteristics of the pattern; and

the generating step includes the step of generating the signal representative of characteristics of the changing position of the pattern in the space in response to the combined phase information.