Automatic piezo stroke adjustment

Patent metadata

Field	Value
Publication number	US-10646893-B2
Application number	US-201615747765-A
Country	US
Kind code	B2
Filing date	Aug 31, 2016
Priority date	Aug 31, 2015
Publication date	May 12, 2020
Grant date	May 12, 2020

Abstract

A method of calibrating the jetting profile includes applying voltage to a piezoelectric actuator to move a valve closure structure between non-impact and impact positions, sensing the position of the valve closure structure, establishing a reference point using voltage and position data, and using the reference point to adjust the voltage applied. Another method uses a mechanical stop to calibrate a jetting system. This method includes applying voltage to the piezoelectric actuator to move the valve closure structure between non-impact and impact calibration positions, sensing the position of the valve closure structure, generating voltage and position calibration data, establishing a master reference point using this data, and using the master reference point to determine wear of at least one of: the piezoelectric actuator and the valve closure structure. Another method of operating a jetting system includes the user inputting information into a control component. Another method involves using voltage data and the position data relating to a piezoelectric actuator for preventative maintenance of one or more components of the jetting valve.

First claim

What is claimed is:

1. A method of calibrating the jetting profile of a jetted fluid material for a jetting system, the jetting system including a jetting dispenser and a control component operatively coupled to the jetting dispenser, the jetting dispenser including a valve seat, a valve closure structure, and a piezoelectric actuation mechanism having a piezoelectric actuator, the method comprising:
applying voltage to the piezoelectric actuator to move the valve closure structure between a non-impact position where the valve closure structure is not impacting the valve seat and an impact position where at least a portion of the valve closure structure is impacting the valve seat;
generating voltage data as the valve closure structure is moved;
sensing the position of the valve closure structure as the valve closure structure is moved using a sensing device;
generating position data as the valve closure structure is moved;
establishing a reference point using the voltage and position data; and
using the reference point to adjust the voltage applied to the piezoelectric actuator.

2. The method of claim 1 , further comprising:
generating velocity data as the valve closure structure is moved; and
establishing a reference point using the voltage, position, and velocity data.

3. The method of claim 2 , wherein using the reference point further comprises:
using the reference point to decrease an impact velocity and increase a sealing force for low-viscosity fluid materials.

4. The method of claim 2 , wherein using the reference point further comprises:
using the reference point to increase an impact velocity and decrease a sealing force for high-viscosity fluid materials.

5. The method of claim 1 , wherein using the reference point further comprises:
using the reference point to determine the wear characteristics of at least one of: the piezoelectric actuation mechanism, the valve closure structure, and valve seat.

6. The method of claim 1 , wherein the sensing device further comprises a linear encoder.

7. The method of claim 1 , wherein sensing the position of the valve closure structure further comprises:
sensing the position of the valve closure structure using a sensing device directly attached to the valve closure structure.

8. The method of claim 1 , wherein establishing a reference point using the voltage and position data further comprises plotting the voltage and position data.

9. The method of claim 1 , wherein the position data further includes non-impact and impact position data, and wherein establishing the reference point further comprise:
generating a first trendline from at least a portion of the non-impact position data;
generating a second trendline from at least a portion of the impact position data; and
determining the intersection of the first and second trendlines to establish the reference point.

10. The method of claim 9 , wherein generating a first and second trendlines and determining the intersection further comprise:
generating a first linear trendline from a linear portion of the non-impact position data;
generating a second linear trendline from a linear portion of the impact position data; and
determining the intersection of the first and second linear trendlines to establish the reference point.

11. A method of calibrating the jetting profile of a jetted fluid material for a jetting system, the jetting system including a jetting dispenser and a control component operatively coupled to the jetting dispenser, the jetting dispenser including a piezoelectric actuation mechanism having a piezoelectric actuator, a valve closure structure, and a mechanical stop positioned at a predetermined distance away from the valve closure structure in a non-impact calibration position, the method comprising:
applying voltage to the piezoelectric actuator to move the valve closure structure between the non-impact calibration position where the valve closure structure is not impacting the mechanical stop and an impact calibration position where at least a portion of the valve closure structure is impacting the mechanical stop;
generating voltage calibration data as the valve closure structure is moved;
sensing the position of the valve closure structure as the valve closure structure is moved using a sensing device;
generating position calibration data as the valve closure structure is moved;
establishing a master reference point using the voltage and position calibration data; and
using the master reference point to determine wear of at least one of: the piezoelectric actuation mechanism and the valve closure structure.

12. The method of claim 11 , wherein using the master reference point further comprises:
storing the master reference point over a period of time;
comparing the stored master reference point to a current master reference point; and
using the comparison to determine the wear or predict preventative maintenance of at least one of: the piezoelectric actuation mechanism and the valve closure structure.

13. The method of claim 11 , wherein using the master reference point further comprises:
storing the position and voltage calibration data over a period of time;
comparing the stored position and voltage calibration data to current position and voltage calibration data; and
using the comparison to determine the wear or predict preventative maintenance of at least one of: the piezoelectric actuation mechanism and the valve closure structure.

14. The method of claim 11 , wherein the piezoelectric actuation mechanism further comprises:
a piezoelectric stack comprising a plurality of piezoelectric elements; and
an amplifier positioned between the piezoelectric stack and the valve closure structure.

15. The method of claim 14 , further comprising:
alerting the user when the wear of at least one of: the piezoelectric actuation mechanism and the valve closure structure is outside of an acceptable tolerance.

16. The method of claim 14 , further comprising:
tracking a number of cycles the valve closure structure impacts the valve seat; and
determining a useful life of at least one of: the piezoelectric actuation mechanism, the valve closure structure, and the valve seat using the voltage and position calibration data and the number of cycles.

17. The method of claim 16 , further comprising:
alerting the user of the useful life of at least one of: the piezoelectric actuation mechanism, the valve closure structure, and the valve seat.

18. The method of claim 14 , further comprising:
tracking a number of cycles the valve closure structure impacts the valve seat;
determining the need for preventative maintenance to at least one of: the piezoelectric actuation mechanism, the valve closure structure, and the valve seat using the voltage and position calibration data and the number of cycles.

19. The method of claim 18 , further comprising:
alerting the user of a need for preventative maintenance to at least one of: the piezoelectric actuation mechanism, the valve closure structure, and the valve seat.

20. A method of calibrating the jetting profile of a jetted fluid material for a jetting system, the jetting system including a jetting dispenser and a control component operatively coupled to the jetting dispenser, the jetting dispenser including a valve seat, a valve closure structure, a piezoelectric actuation mechanism having a piezoelectric actuator, and a mechanical stop positioned at a predetermined distance away from the valve closure structure

Assignees

• Nordson Corp

Inventors

• Burzo Christopher
• Gorman Michael
• Lewis Alan R
• Crowell Iii Cutler

Classifications

• B05C5/022

  the outlet being fixed during operation · CPC title

• B05C11/1034

  specially designed for conducting intermittent application of small quantities, e.g. drops, of coating material (B05C5/0225, B05C11/1026 take precedence) · CPC title

• B05C5/0225 Primary

  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 title

• H05K13/0469

  by applying a glue or viscous material · CPC title

• H05K13/08

  Monitoring manufacture of assemblages · CPC title