Waterproof control unit and method of assembling the same

A waterproof control unit, comprising:

• a base and a cover;
• a circuit board that is hermetically housed in a casing comprising the base and the cover, and has circuit components mounted thereon;
• a connector housing that is positioned and fixed to the circuit board, and allows a plurality of contact terminals to pass therethrough via a partition wall;
• and
• a waterproof sealing material filled into each of a first sealing gap defined between opposing surfaces of the connector housing and the cover, a second sealing gap defined between opposing surfaces of the connector housing and the base, and a third sealing gap defined between directly-opposing surfaces of the base and the cover, so as to expose, from an opening portion of a side surface of the cover, an external-connection end surface of the connector housing,
• wherein the connector housing is made of a resin forming material, and a first opposing surface, which comprises a flat surface and an inclined surface forming one of the opposing surfaces of the first sealing gap, is formed on three sides of an outer periphery of the connector housing,
• wherein a second opposing surface, which comprises a flat surface and an inclined surface forming one of the opposing surfaces of the second sealing gap, is formed on one remaining side of the outer periphery of the connector housing serving as a bottom surface thereof,
• wherein the inclined surface of the first opposing surface comprises a slope portion connecting an outer-step flat portion and an inner-step flat portion in a stepped manner, or a first convex thread having a triangular cross-section,
• wherein the inclined surface of the second opposing surface comprises any one of a slope portion connecting an outer-step flat portion and an inner-step flat portion in a stepped manner, a second concave thread having a trapezoid cross-section, or an undulating deformation portion having a recessed cross-section,
• wherein the first opposing surface and the second opposing surface extend across an inner boundary surface of the partition wall toward an inside and an outside of the casing,
• wherein the connector housing further comprises a looped peripheral wall formed at a position of the outer periphery of the connector housing exposed from the casing, and a pair of side-surface convex threads formed on both side surfaces at a position of an unexposed end surface of the connector housing,
• wherein the looped peripheral wall is opposed to an opening side surface of the cover and an end surface of the base with an opening gap (H),
• wherein the side-surface convex threads function as plane movement regulating members that are fitted into a pair of side-surface concave threads formed in the cover, and
• wherein a relative position between the connector housing and the cover is regulated by the plane movement regulating members so that a plane movement gap dimension of the first sealing gap is kept within a predetermined range of fluctuation.