Soldering iron with automatic soldering connection validation

Patent metadata

Field	Value
Publication number	US-9516762-B2
Application number	US-201514794678-A
Country	US
Kind code	B2
Filing date	Jul 8, 2015
Priority date	Aug 4, 2014
Publication date	Dec 6, 2016
Grant date	Dec 6, 2016

Abstract

A soldering iron station and a method thereof for a soldering joint connection validation, the method including: identifying a type of the soldering cartridge being used; performing a preliminary validation by measuring the soldering tip temperature, after the soldering event has started; monitoring the power level delivered to the soldering tip to detect liquidus occurrence; determining the thickness of an intermetallic component (IMC) of the soldering joint; determining whether the thickness of the IMC is within a predetermined rage, within a predetermined cooling time period; and indicating that a reliable soldering joint connection is formed, when the thickness of the IMC is within the predetermined rage, within the predetermined cooling time period.

First claim

What is claimed is:

1. A method performed by a handheld soldering iron station for a soldering joint connection validation, the handheld soldering iron station including a soldering cartridge having a soldering tip, the method comprising:
identifying a type of the soldering cartridge being used by the soldering iron station and obtaining information related to the identified cartridge;
determining that a soldering event has started by measuring a power level delivered to the soldering tip, within a first predetermined time period;
performing a preliminary validation by measuring a soldering tip temperature, after the soldering event has started;
monitoring the power level delivered to the soldering tip to detect liquidus occurrence;
determining a thickness of an intermetallic component (IMC) of the soldering joint as a function of soldering time and soldering tip temperature, after detect the liquidus occurrence;
determining whether the thickness of the IMC is within a predetermined range, within a predetermined cooling time period; and
indicating that a reliable soldering joint connection is formed, when the thickness of the IMC is within the predetermined range, within the predetermined cooling time period.

2. The method of claim 1 , wherein identifying a type of the soldering cartridge being used and obtaining information related to the identified cartridge comprises retrieving data from a memory within the soldering iron station, or from a memory remote from the soldering iron station.

3. The method of claim 1 , wherein measuring a soldering tip temperature comprises measuring an impedance of the soldering tip and determining the soldering tip temperature as a function of the measured impedance.

4. The method of claim 1 , wherein measuring a soldering tip temperature comprises defining a thermal efficiency factor for a geometry of the soldering tip and a heater material and determining the soldering tip temperature as a function of the thermal efficiency and the powered delivered to the soldering tip.

5. The method of claim 1 , wherein the liquidus occurrence is detected when the monitored power is declining from a peak.

6. The method of claim 1 , wherein the predetermined range of the thickness of the IMC is 1 μm-4 μm.

7. The method of claim 1 , further comprising performing a thermal efficiency check and aborting the method when the thermal efficiency check fails.

8. A soldering iron station with automatic soldering joint connection validation comprising:
a hand piece including a soldering cartridge having a soldering tip;
a power supply for delivering power to the soldering tip;
an indicator; and
a processor including associated circuits for identifying a type of the soldering cartridge being used by the soldering iron station and obtaining information related to the identified cartridge; performing a preliminary validation by measuring a soldering tip temperature; monitoring the power level delivered to the soldering tip to detect liquidus occurrence; determining a thickness of an intermetallic component (IMC) of the soldering joint as a function of soldering time and soldering tip temperature, after detecting the liquidus occurrence; and determining whether the thickness of the IMC is within a predetermined range, within a predetermined cooling time period, wherein
the indicator indicates that a reliable soldering joint connection is formed, when the thickness of the IMC is within the predetermined range, within the predetermined cooling time period.

9. The soldering iron station of claim 8 , wherein the soldering iron station further includes a non-volatile memory (NVM) for storing data related to the cartridge, and wherein the processor identifies the type of the soldering cartridge being used and obtains information related to the identified cartridge by retrieving data from the NVM.

10. The soldering iron station of claim 9 , wherein data related to the cartridge stored in the NVM includes one or more of a part number, lot code, a serial number, a total usage, a total point, a tip mass/weight, a tip configuration, an authentication code, a thermal efficiency, and a thermal characteristic.

11. The soldering iron station of claim 8 , further comprising a temperature sensor for measuring the soldering tip temperature.

12. The soldering iron station of claim 8 , wherein the processor detects the liquidus occurrence when the monitored power is declining from a peak.

13. A method performed by a handheld soldering iron station for a soldering joint connection validation, the handheld soldering iron station including two cameras for capturing respective images of the soldering joint from different views, the method comprising:
capturing a 2-dimensional (2D) reference image of the soldering joint by each of the cameras, before a soldering event starts;
generating a 3-dimensional (3D) reference image of the soldering joint from the captured 2D reference images;
determining an amount of solder needed to fill in a barrel of a hole for a through hole component, or to fill in a surface of a barrel of a hole for a surface mount component, from the 3D reference image;
capturing a 2D current image of the soldering joint by each of the cameras, after the soldering event starts;
comparing a value of each pixel in each of the 2D current images to corresponding pixel values in the 2D reference images, respectively to detect any color changes of the pixels in the 2D current images due to spread of a dispensed solder, as the soldering event progresses;
repeating capturing a 2D current image and comparing a value of each pixel, until all the pixels in the 2D current images are determined to be pixels of the dispensed solder to detect an occurrence of a liquidus of the dispensed solder;
after detection of the occurrence of the liquidus, generating a 3D current image of the soldering joint from the last captured 2D reference image from each camera;
determining volume of the dispensed solder after occurrence of the liquidus from the 3D current image;
comparing the volume of the dispensed solder to the determined amount of solder needed to fill in the barrel or the surface area of the barrel to determine how much of the dispensed solder is dissipated into the barrel or on the surface area of the barrel;
repeating the comparing of the volume of the dispensed solder until the dispensed solder has filled the barrel or the surface area of the barrel, within a predetermined tolerance; and
activating an indicator to indicate a good solder joint connection, when the dispensed solder has filled the barrel or the surface area of the barrel within the predetermined tolerance.

14. The method of claim 13 , wherein comparing a value of each pixel in each of the 2D current images comprises comparing a color value of each pixel in each of the 2D current images to corresponding pixel color values in the 2D reference images, respectively in relation to a known color pixel value of solder.

15. The method of claim 14 , wherein detection of the occurrence of the liquidus of the dispensed solder is determined when all of the pixel color values in the last two 2D current images are equal to the known color pixel value of solder, within a tolerance range.

16. The method of claim 13 , further comprising aborting the method when within a predetermined time period, not all the pixels in the 2D current images are determined to be pixels of the dispensed solder.

17. The method of claim 13 , further comprising aborting the method when within a predetermined time period, the dispensed solder has not fil

Assignees

• Capital Formation Inc
• Ok Int Inc

Inventors

• Marino Kenneth D
• Nguyen Hoa

Classifications

• B23K2101/42

  Printed circuits · CPC title

• B23K3/08

  Auxiliary devices therefor · CPC title

• B23K1/0016 Primary

  Soldering of electronic components · CPC title

• B23K3/033

  comprising means for controlling or selecting the temperature or power · CPC title

• B23K3/02

  Soldering irons; Bits · CPC title