HIGH-TEMPERATURE ELECTRONICS ENCLOSURE

THE CLIENT’S NEED

After decades in business, the largest supplier of thermal profiling data-acquisition devices for characterizing wave and reflow solder ovens contracted NOVO to design its next-generation device in response to customer requests for a smaller, sleeker design. The existing profilers, which were large and unwieldy, helped prevent defects in surface-mounted PCBs that could result from charring, cracking, or spattering if reflow solder ovens became too hot or heated too quickly. NOVO was engaged for the mechanical and industrial design (ID) needed to enclose electronics designed by the client’s in-house staff.

THE TECHNICAL AND DESIGN CHALLENGES

This project’s primary challenge was to ensure a ruggedized electronics packaging design capable of withstanding rough handling in an industrial environment, and the high process temperature of the ovens used in surface-mount technology (SMT). Differential thermal expansion at the elevated temperatures posed a challenge at component interfaces. A high-temperature material set that met competing requirements for manufacturing costs, feature resolution, ID, and durability had to be identified.

THE ENGINEERING BEHIND GREAT PRODUCTS

NOVO engineers responded with a sleek design consisting of an extruded aluminum body with Ultem® endcaps. Provision for thermal expansion was made by properly designing the joints and tolerancing the components. The extruded aluminum body functioned as a thermal mass and while lending itself to an attractive, minimalist design. The injection-molded Ultem material allowed complex geometry and temperature resistance, but required a specific molding process. The enclosure was designed to allow the RF communication between the device and the receiver plugged into a USB port on the host PC.

Throughout the project, the engineers coordinated extensively with the client staff to successfully integrate the electronics into the housing, and with vendors to mold the plastic parts. Although the client company had the highest sales worldwide, their staff was small, and they did not have a large service and repairs department that could reach the remote locations where the device was often used. NOVO worked directly with field service representatives to investigate failures that had occurred in the previous-generation product and to incorporate features into the new design to eliminate those failure modes.

NOVO also included a battery compartment cover and an adapter for older thermocouple probes. The robust design has been a success around the world for several years and continues to be the most widely-used brand on the market for PCA line quality control.