Portable equipment for monitoring and controlling the level of oxygen in reflow oven atmosphere

Patent metadata

Field	Value
Publication number	US-9539672-B2
Application number	US-201314651836-A
Country	US
Kind code	B2
Filing date	Nov 26, 2013
Priority date	Dec 14, 2012
Publication date	Jan 10, 2017
Grant date	Jan 10, 2017

Abstract

The present invention describes a portable device for monitoring and controlling the level of residual oxygen in reflow oven atmosphere ( 1 ). This referred equipment is able to determine the quality of the atmosphere of a reflow oven, using parameters predetermined by the user. Therefore, the equipment performs the monitoring of the reflow oven atmosphere ( 1 ) controlling the level of residual oxygen of the reflow oven ( 1 ) by increasing or decreasing of the feed flow rate of nitrogen by the control that the microcontroller exerts over the proportional valve of nitrogen flow control ( 9 ), by opening or closing the valves to kept such predetermined values.

First claim

The invention claimed is:

1. Portable equipment for monitoring and controlling the atmosphere of reflow ovens, comprising:
a nitrogen injection flow control box comprising at least one ball-type manual valve, at least one nitrogen pressure regulator with pressure gauge, a proportional valve of nitrogen flow control; and a cleaning line comprising a ball-type manual valve of the cleaning line and nitrogen pressure regulator of the cleaning line with a manometer;
a collecting and analysis box comprising a line filter, at least one solenoid valve, a lambda sensor coupled with an analysis chamber, a signal converter, a flow meter with needle valve, and a diaphragm-type vacuum pump; and
a box with a programmable controller, and a display with communicative interface comprising of a microcontroller, and a signal converter the lambda sensor coupled with an analysis chamber connected with one to another by electrical cables.

2. The portable equipment according to claim 1 , wherein the cleaning line is used for cleaning a sampling system utilizing nitrogen.

3. The portable equipment according to claim 1 , wherein the solenoid valve controls the flow rate of a cleaning sample or nitrogen.

4. The portable equipment, according to claim 1 , wherein a desired value of oxygen in the reflow surroundings is preselected through a communicative interface.

5. The portable equipment, according to claim 1 , wherein the lambda sensor coupled to an analysis chamber sends electrical signal to the signal converter.

6. The portable equipment, according to claim 1 , wherein the microcontroller uninterruptedly evaluates and controls oxygen values collected in the collecting and analysis box of samples and makes a comparison with values of the atmosphere predetermined by a user.

7. The portable equipment, according to claim 1 , wherein the microcontroller sends a control signal to the control box of nitrogen flow that coordinates opening and closing of the proportional valve of nitrogen flow control.

Assignees

• L'Air Liquide Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude

Inventors

• Rodrigues Luiz
• Neryz Maicon Renan

Classifications

• H05K2203/163

  Monitoring a manufacturing process · CPC title

• H05K3/3494 Primary

  Heating processes for reflow soldering · CPC title

• B23K35/383 Primary

  mainly containing noble gases or nitrogen · CPC title

• B23K35/38

  Selection of media, e.g. special atmospheres for surrounding the working area · CPC title

• B23K1/012

  Soldering with the use of hot gas · CPC title