Heat Diffuser Box

A manufacturer of printed circuit board rework stations needed an assembly to pre-heat circuit boards using heated air to minimize warping of the board as rework was taking place.

Project and Challenges

The area for the assembly was limited to a depth of only 2.50 inches.

Even temperatures across the face of the diffuser were important to prevent the distortion of the boards.

A logic level signal to verify airflow was requested as well.

Solutions and Their Impact

A motorized impeller was integrated into the diffuser box, along with an internal baffle, and heating element to provide an efficient compact package. The internal baffle directs the air directly over the resistance coils of the heating element. From there, the air is dispersed evenly across the top face via the holes in the diffuser.

A self-heated thermistor circuit was designed to provide the requested logic level airflow signal.