Electrical outlet box assembly

An electric box assembly for mounting an outlet box within an opening extending between opposite surfaces of a panel, comprising:

• a ring member having a sidewall adapted to be inserted into and seated within said opening said sidewall having inner and outer surfaces, a first flange extending outwardly from the outer surface of said sidewall and adapted to bear against one surface of said panel, and first cam means on one of said surfaces of said sidewall;
• and an outlet box meamber having a sidewall adapted to be positioned within the sidewall of said ring member, a second flange extending outwardly from the sidewall of said outlet box member and adapted to bear against the surface of said panel opposite to the surface engaged by said first flange on said ring member, and second cam means on the sidewall of said outlet box member and adapted to engage said first cam means when said outlet box member is moved relative to said ring member, said second cam means including a plurality of sets of lugs, each set of lugs being located on a plane extending parallel to said second flange with the respective planes being spaced different distances from said second flange, so any one of said plurality of sets of lugs can cooperate with said first cam means to move the flanges on said ring member and outlet box member with respect to one another to clampingly engage said panel therebetween, whereby to accommodate panels of different thickness.

An electric box assembly for mounting an outlet box within an opening extending between opposite surfaces of a panel, comprising:

• a ring formed of a material with an inherently elastic memory and having a generally cylindrically-shaped sidewall having inner and outer surfaces adapted to be inserted into and seated within said opening and having first and second edges;
• a flange extending outwardly from the outer surface of said sidewall and adapted to bear against one surface of said panel, said flange being located opposite ends of said sidewall and closer to one sidewall end than the other sidewall end;
• and means on the inner surfaces of said sidewall defining cam track means inclined away from the end of the ring member inserted into the panel opening and defining a ratchet means having a plurality of alternating crests and troughs on a bearing surface of the cam track means, said sidewall being discontinuous and defining a gap to permit said ring member sidewall to be spread apart from a relaxed position, wherein the diameter of said outer surface is greater than the diameter of said opening to a spread position wherein the gap is greater than the thickness of the panel whereby the ring member may be inserted through said panel opening by (1) placing one portion of the sidewall adjacent the gap outside the panel, and (2) rotating the ring member relative to the panel to position the entire ring member outside the panel and in the relaxed position, said ring member then being insertable in said opening by (1) compressing the ring member from said relaxed position to a compressed position wherein the diameter of said outer surface is smaller than the diameter of said opening, (2) telescopically inserting said ring member in said opening until the flange thereon engages said one panel surface, and (3) releasing the force compressing said ring member whereby the inherent elastic memory of said ring member urges said sidewall toward said relaxed position to position the outer surface of said sidewall between said flange and one sidewall end in frictional retentive engagement with the wall of said opening, said ring member being reversible from a first position wherein one surface of said flange is adapted to bear against said one surface of said panel and the portion of said sidewall between said flange and said one end engages the wall of said opening, to a second position wherein a second surface of said flange is adapted to bear against said one surface of said panel and the portion of said sidewall between said flange and said other of said ends engages the wall of said opening, to thereby accommodate panels of greater variation thicknesses than when the ring is in either position;
• and an outlet box member having a sidewall adapted to be positioned within the sidewall of said ring member;
• a flange extending outwardly from the sidewall of said outlet box member and adapted to bear against the opposite surface of said panel;
• and cam follower means on the sidewall of said outlet box member and having a bearing surface adapted to engage said cam track means when said outlet box member is rotated relative to said ring member;
• said bearing surface having a profile generally complementary to the shape of said cam track means and receivable in said troughs between successive crests, whereby said cam and cam follower means cooperate to move the flanges on said ring member and outlet box member toward one another and into clamping engagement with said panel, as said cam follower means moves along said inclined cam track means, and said cam follower means and cam track means cooperate to minimize the possibility of dislodgement of said outlet box member from said ring member.

A ring member for an electric box assembly for mounting an outlet box within an opening extending between opposite surfaces of a panel, comprising a generally cylindrical sidewall adapted to be seated within said opening, said sidewall having inner and outer surfaces and opposite ends, a flange integral with said sidewall and extending outwardly from said outer surface, said flange having first and second opposed surfaces extending perpendicular to the axis of said generally cylindrical sidewall, said first surface of said flange being spaced a greater distance from one end of said sidewall than said second surface is spaced from the opposite end of said sidewall, said sidewall and flange being formed of a material with an inherent elastic memory and being discontinuous to define a gap permitting said ring member sidewall to be spread apart and compressed from a relaxed position, and a plurality of circumferentially spaced cam tracks integral with said sidewall and extending inwardly from said inner surface, each of cam tracks comprising a thin rib having opposed parallel surfaces inclined with respect to a plane extending parallel to said first and second surfaces of said flange, said ribs having opposite ends respectively located on planes extending parallel to said plane so that either of said first and second surfaces can be positioned to engage a surface of said panel to accommodate panels of different thickness.

An outlet box adapted to cooperate with a ring member having a set of circumferentially spaced cam tracks with the adjacent ends of each pair of cam tracks spaced from each other, the total circumferential dimension of the cam tracks encompassing substantially the entire ring and the total spacing between adjacent cam tracks being a small fraction of the overall circumferential dimension of the ring, said outlet box comprising a cylindrical sidewall having a first end and a second end, a flange extending outwardly from said first end of said sidewall and defining a surface between said ends which extends perpendicular to a center axis of said cylindrical sidewall, a plurality of sets of circumferentially spaced lugs extending outwardly from said sidewall with each set of lugs located on a plane extending parallel to said surface and the respective planes being spaced different distances from said surface, the circumferential dimension of each lug being less than the spacing between adjacent pairs of cam tracks so that the total circumferential dimension of each set of lugs is less than said small fraction, each of said circumferentially spaced lugs of one set being axially aligned with a lug of the other sets so that said outlet box may be inserted through a ring member having a single set of cam track members equal in number to the lugs in a set and the lugs of a set engage the respective cam track members.