Jetting Apparatus and Method of Improving the Performance of a Jetting Apparatus

• US 20090266906A1
• Filed: 11/14/2006
• Published: 10/29/2009
• Est. Priority Date: 11/14/2005
• Status: Active Grant

• Current Assignee: Mycronic AB
• Original Assignee: MYDATA automation AB (Mycronic AB)
• Inventors: Holm, William, Kronstedt, Johan, Sandell, Hakan
• Granted Patent: US 8,453,595 B2
• Time in Patent Office: Days
• US Class Current: 239/1
• CPC Class Codes: B05B 17/06 using ultrasonic or other kinds of vibrations
• CPC Class Codes: B05B 17/0623 coupled with a vibrating horn
• CPC Class Codes: B05B 7/0408 with arrangements for mixing two or more liquids
• CPC Class Codes: B05B 7/0483 with gas and liquid jets intersecting in the mixing chamber
• CPC Class Codes: B05C 11/1034 specially designed for conducting intermittent application of small quantities, e.g. drops, of coating material B05C5/0225, B05C11/1026 take precedence
• CPC Class Codes: B05C 5/022 the outlet being fixed during operation
• CPC Class Codes: B05C 5/0225 characterised by flow controlling means, e.g. valves, located proximate the outlet B05C5/0258, B05C5/0275 take precedence; supply valves upstream the coating head B05C11/1036
• CPC Class Codes: B23K 3/0623 for shaped solder piece feeding, e.g. preforms, bumps, balls, pellets, droplets
• CPC Class Codes: B23K 3/082 Flux dispensers; Apparatus for applying flux

Abstract

A jetting apparatus (15) for jetting droplets of viscous medium onto a substrate and a method of improving the performance of the jetting apparatus. The jetting apparatus (15) includes a jetting outlet (27) through which the droplets are jetted, a flow generator for producing a flow of air past the jetting outlet for removing viscous medium residue at the jetting outlet (27), a receptacle (55) for receiving viscous medium residue transported by the air flow away from the jetting outlet (27), and a flow path (58) for the air flow between the jetting outlet (27) and the flow generator, via the receptacle. A flow sensor (70) is arranged in the flow path (58) for measuring the air flow. An air flow signal representative of the air flow is obtained, the air flow signal is evaluated for determining at least one status of the jetting apparatus (15), and an indication of the status is provided.

Claims

1. A method of improving the performance of a jetting apparatus for jetting individual droplets of viscous medium onto a substrate, said jetting apparatus including a jetting outlet through which said droplets are jetted, a flow generator for producing a flow of air past the jetting outlet for removing viscous medium residue at the jetting outlet, a receptacle for receiving viscous medium residue transported by said air flow away from the jetting outlet, and a flow path for said air flow between said jetting outlet and said flow generator, via said receptacle, comprising the steps of:

measuring the air flow in said flow path and obtaining an air flow signal representative of said air flow;

evaluating said air flow signal for determining at least one status of said jetting apparatus; and

providing an indication of said status.

2. The method as claimed in claim 1, wherein said step of evaluating comprises:

comparing the said air flow signal to one or more threshold values, each threshold value being representative of at least one status of said jetting apparatus.

3. The method as claimed in claim 1, wherein said step of evaluating comprises:

monitoring the variation in said air flow, and comparing said variation to chosen threshold values indicating at least one status of the jetting apparatus.

4. The method as claimed in claim 1, wherein said step of evaluating comprises:

evaluating said air flow signal to indicate a status of air flow leakage.

5. The method as claimed in claim 1, wherein said step of evaluating comprises:

evaluating said air flow signal to indicate a status of occurring or non-occurring jetting operation.

6. The method as claimed in claim 1, wherein said step of evaluating comprises:

evaluating said air flow signal to indicate a status of a certain filling ratio of the receptacle.

7. The method as claimed in claim 1, wherein said receptacle includes a filter through which the flow of air is guided in the receptacle, wherein said step of evaluating comprises:

evaluating said air flow signal to indicate a status of a certain clogging degree of said filter.

8. The method as claimed in claim 1, comprising the steps of:

evaluating, in said step of evaluating, said air flow signal to indicate a status of obstructed air flow; and

indicating that the air flow is so low that the accuracy of the jetting operation may be affected.

9. The method of claim 8, wherein said obstructed air flow is a result of at least one of the receptacle being substantially full with viscous medium, and a filter of the receptacle being substantially clogged with viscous medium.

10. The method as claimed in claim 1, comprising the steps of:

evaluating said air flow signal to indicate a status of temporary minor obstruction of the air flow.

11. The method as claimed in claim 1, comprising the steps of:

evaluating said air flow signal during occurring jetting operation to indicate a status related to amount of generated viscous medium residue per time period.

12. The method as claimed in claim 11, wherein said status related to amount of generated viscous medium residue per time period represents the performance of the jetting operation.

13. The method as claimed in claim 1, further comprising the step of:

preventing the jetting of viscous medium when the evaluation of air flow and indication of status of said jetting apparatus indicates that the performance of the jetting operation may be in jeopardy.

14. The method as claimed in claim 13, wherein said jetting is prevented when said status indicates the possibility of at least one of a leakage in the flow path and an erroneous assembly of the jetting apparatus.

15. The method as claimed in claim 13, wherein said jetting is prevented when said status indicates that the flow of air is significantly obstructed in said receptacle.

16. The method as claimed in claim 1, further comprising the steps of:

storing said air flow signal for providing air flow information of the jetting operation related to a particular substrate or group of substrates; and

inspecting the results of said jetting operation related to a particular substrate or group of substrates utilizing said air flow information for indicating when and for which droplet(s) there is an increased probability of reduced jetting performance due to air flow variation.

17. The method as claimed in claim 1, further comprising the step of:

storing said air flow signal for providing air flow information of the jetting operation; and

utilizing said air flow information for adjusting the jetting operation and improving the performance thereof.

18. A jetting apparatus for jetting individual droplets of viscous medium onto a substrate, including a jetting outlet through which said droplets are jetted, a flow generator for producing a flow of air past the jetting outlet for removing viscous medium residue at the jetting outlet, a receptacle for receiving viscous medium residue transported by said air flow away from the jetting outlet, and an air flow path for said air flow between said jetting outlet and said flow generator, via said receptacle, the jetting apparatus comprising:

an air flow meter for measuring the air flow in said air flow path, said air flow meter including a flow sensor positioned in the air flow path, said air flow meter being arranged for outputting an air flow signal representative of the air flow in the air flow path, and

a processor arranged for receiving said flow signal from the air flow meter, evaluating said flow signal, and outputting an indication of a status of the jetting apparatus.

19. The jetting apparatus as claimed in claim 18, wherein the processor is arranged for

comparing the said air flow signal to one or more threshold values, each threshold value being representative of at least one status of said jetting apparatus.

20. The jetting apparatus as claimed in claim 18, wherein the processor is arranged for

monitoring the variation in said air flow, and comparing said variation to chosen threshold values indicating at least one status of the jetting apparatus.

21. The jetting apparatus as claimed claim 18, wherein the processor is arranged for

evaluating said air flow signal to indicate a status of air flow leakage.

22. The jetting apparatus as claimed in claim 18, wherein the processor is arranged for

evaluating said air flow signal to indicate a status of occurring or non-occurring jetting operation.

23. The jetting apparatus as claimed in claim 18, wherein the processor is arranged for

evaluating said air flow signal to indicate a status of a certain filling ratio of the receptacle.

24. The jetting apparatus as claimed in claim 18, further comprising a viscous medium filter arranged in the receptacle, wherein the flow of air is guided through the filter within the receptacle,

wherein the processor is arranged for evaluating said air flow signal to indicate a status of a certain clogging degree of said filter.

25. The jetting apparatus as claimed in claim 18, wherein the processor is arranged for

evaluating, in said step of evaluating, said air flow signal to indicate a status of obstructed air flow;

and

indicating that the air flow is so low that the accuracy of the jetting operation may be affected.

26. The jetting apparatus of claim 25, wherein said obstructed air flow is a result of at least one of the receptacle being substantially full with viscous medium, and a filter of the receptacle being substantially clogged with viscous medium.

27. The jetting apparatus as claimed in claim 18, wherein the processor is arranged for

evaluating said air flow signal to indicate a status of temporary minor obstruction of the air flow.

28. The jetting apparatus as claimed in claim 18, wherein the processor is arranged for

evaluating said air flow signal during occurring jetting operation to indicate a status related to an amount of generated viscous medium residue per time period.

29. The jetting apparatus as claimed in claim 28, wherein said status related to the amount of generated viscous medium residue per time period represents the performance of the jetting operation.

30. The jetting apparatus as claimed in claim 18, wherein the processor is arranged for

preventing the jetting of viscous medium when the evaluation of air flow and indication of status of said jetting apparatus indicates that the performance of the jetting operation may be in jeopardy.

31. The jetting apparatus as claimed in claim 30, wherein said processor is arranged for

preventing the jetting when said status indicates the possibility of at least one of a leakage in the flow path and an erroneous assembly of the jetting apparatus.

32. The jetting apparatus as claimed in claim 30, wherein said processor is arranged for

preventing the jetting when said status indicates that the flow of air is significantly obstructed in said receptacle.

33. The jetting apparatus as claimed in claim 18, wherein said jetting apparatus further comprises:

storing means for storing said air flow signal for providing air flow information of the jetting operation related to a particular substrate or group of substrates; and

an inspection unit arranged for inspecting the results of said jetting operation related to a particular substrate or group of substrates utilizing said air flow information for indicating when and for which droplet(s) there is an increased probability of reduced jetting performance due to air flow variation.

34. The jetting apparatus as claimed in claim 18, wherein said processor is arranged for

storing said air flow signal for providing air flow information of the jetting operation;

and

utilizing said air flow information for adjusting the jetting operation and improving the performance thereof.

35. The jetting apparatus as claimed in claim 18, wherein the flow sensor is positioned in the air flow path between the flow generator and the receptacle.