Temperature control system for large temperature difference adjustment of reflow soldering machine and temperature control method

Abstract

The invention discloses a temperature control system for the large temperature difference adjustment of a reflow soldering machine and a temperature control method. The control system comprises a programmable logic controller, a plurality of cold air transmission pipelines, refrigerating systems, temperature detection units as well as electromagnetic valves installed on the cold air transmission pipelines and controlled by the programmable logic controller, and the programmable logic controller is connected with heating mechanisms arranged in upper and lower temperature subareas of a plurality of temperature areas. The temperature control method comprises the following steps: 1, newly set temperatures for the upper and the lower temperature subareas in the plurality of temperature areas are input respectively to the programmable logic controller; and 2, the programmable logic controller performs control and adjustment to the temperatures of the upper and the lower temperature subareas in the plurality of temperature areas, including quick temperature adjustment, appropriate temperature adjustment and heat preservation. The temperature control system has the advantages of reasonable design and good use effect, is convenient for installation, arrangement and wiring, and is easy to operate. Besides solving the problem of slow temperature reduction, the temperature control system is used for rapidly and conveniently adjusting the temperature difference between adjacent temperature areas, and addresses the difficulty in setting a temperature difference between an upper temperature area and a lower temperature area of a PCB (Printed Circuit Board).

Description

technical field [0001] The invention belongs to the technical field of temperature control systems for reflow soldering machines, and in particular relates to a temperature control system and a temperature control method for adjusting a large temperature difference of a reflow soldering machine. Background technique [0002] At present, tunnel furnaces and reflow soldering machines often use hot air circulation heating to increase the temperature of each temperature zone. In actual use, when the set temperature drops, the only way to cool down is to stop the hot air circulation so that the temperature in the corresponding temperature zone will naturally cool down, so the cooling process is slow and time-consuming. At the same time, due to the influence of heat transfer, it is also difficult to increase the temperature difference between the set temperatures of adjacent temperature zones by using this temperature control method. In addition, in the actual operation process, ...

AI Technical Summary

Problems solved by technology

In the actual use process, when the set temperature drops, the only way to cool down is to stop the hot air circulation so that the temperature in the corresponding temperature zone will naturally cool down, so the cooling process is slow and time-consuming

At the same time, due to the influence of heat transfer, it is difficult to increase the temperature difference between the set temperatures of adjacent temperature zones by using this temperature control method.

In addition, in the actual operation process, due to the poor heat resistance of the parts located on the upper part of the PCB, the temperature in the upper temperature zone of the PCB board often needs to be lower than the temperature in the lower temperature zone during the soldering process, and the existing temperature control methods cannot solve the problem. The problem of controlling and adjusting the temperature difference between the set temperature of the upper temperature zone and the lower temperature zone in the same temperature zone

Images