Oxygen detection system and reflow furnace using the same

An oxygen detection system for a reflow furnace comprising n furnace chambers and n gas channels, each gas channel T(i)(i=1, 2, . . . n) of the n gas channels having a gas channel inlet R(i=1, 2, . . . n) and a gas channel outlet C(i)(i=1, 2, . . . n), each furnace chamber L(i) (i=1, 2, . . . n) of the n furnace chambers being in fluid communication with the gas channel inlet R(i) of one gas channel T(I) of the n gas channels, wherein:

• the n furnaces and the n gas channels are divided into at least two groups, the at least two groups comprising a first group of furnace chambers, a second group of furnace chambers, a first group of gas channels, and a second group of gas channels, wherein the first group of furnace chambers comprises j furnace chambers, the first group of gas channels comprises j gas channels, the second group of furnace chambers comprises k furnace chambers, the second group of gas channels comprises k gas channels;
• the first group of furnace chambers is in fluid communication with the first group of gas channels, and the second group of furnace chambers is in fluid communication with the second group of gas channels, wherein j+k=n,
• the oxygen detection system comprising:
• a first gas receiving device comprising a first chamber configured to be in switchable fluid communication with a gas channel outlet C(i) of each gas channel T(i) of the first group of gas channels such that gas in each furnace chamber L(i) of the first group of furnace chambers is switchable into the first chamber;
• a second gas receiving device comprising a second chamber configured to be in switchable fluid communication with a gas channel outlet C(i) of each gas channel T(i) of the second group of gas channels such that gas in each furnace chamber L(i) of the second group of furnace chambers is switchable into the first chamber;
• an oxygen detection device switchably in fluid communication with the first chamber and the second chamber;
• a gas suction device switchably in fluid communication with the first chamber and the second chamber;
• and
• a chamber switching device switchably communicating the oxygen detection device with one of the first chamber and the second chamber, and the chamber switching device switchably communicating the gas suction device with the other of the first chamber and the second chamber in fluid communication;
• wherein,
• the second chamber is in fluid communication with the oxygen detection device while the chamber switching device enables the fluid communication of the first chamber and the second chamber and the second chamber is in fluid communication with the gas suction device;
• and
• wherein, when the chamber switching device fluidly connects the second chamber with the oxygen detection device, the first chamber is fluidly isolated from the oxygen detection device and the first chamber is in fluid communication with the gas suction device.