Casing unit for circuit assembly and method for producing the circuit assembly

摘要

A power circuit section (1) is adhered to a circuit arrangement surface (2a) on a heat radiation member (2) to form a circuit assembly. A casing body (30) is mounted on the heat radiation member. The casing body is provided with an opening (32) that exposes at least the upper portion of the power circuit section. A shape retention member (38) is disposed across the opening for interconnecting a peripheral edge of the opening to each other at one or a plurality of positions. A casing unit is made of a synthetic resin. The shape retention member suppresses a deformation of the casing body due to a shrinkage cavity. After cooling the casing unit, the shape retention member is removed to define a large opening, if desired.