Fastening mechanism for access panels and grills using screw driven arm

A detachable grill device for covering an opening in a structure, duct or appliance, said grill device comprising:

• a generally flat grill having inner and outer sides;
• an elongate fastening arm member positioned adjacent said inner side and extending during use thereof generally parallel to said inner side, said arm member being pivotable relative to said grill between a first position used for insertion of said arm member into said opening and a second position used for clamping said grill to edge structure defining said opening;
• a slideway connected to said inner side of the grill and limiting the extent of pivotable movement of said arm member relative to said grill;
• a threaded member having a head at one end thereof and a stop at an opposite end thereof, said threaded member extending from said head through a hole formed in the grill and then through a threaded hole formed in a central section of said arm member and connecting said arm member to said grill;
• and
• a spring acting on said arm member to bias said arm member so that the arm member pivots towards said second position,
• wherein in said second position, said arm member travels towards said grill when said threaded member is turned in one predetermined direction so that said edge structure can be clamped between opposite end sections of said arm member and said grill.

A cover device for covering an opening in a structure, duct or appliance, said device comprising:

• a cover with a peripheral edge portion, an inner side and an outer side;
• an elongate fastening member located adjacent said inner side and extending during use thereof generally parallel to said inner side, said fastening member being pivotable relative to said cover and about a pivot axis perpendicular to said cover between a first position usable for insertion of said fastening member into said opening and a second position used for clamping said cover to edge structure defining said opening;
• means provided on said cover for limiting the extent of said pivotable movement of said fastening member relative to said cover;
• a threaded member having a head at one end, extending through a hole formed in said cover and a threaded hole formed in said fastening member, and connecting said fastening member to said cover;
• and
• means for biasing said fastening member so that said fastening member pivots about said pivot axis towards said second position;
• wherein in said second position said fastening member moves towards said inner side when said threaded member is turned in one predetermined direction so that said edge structure can be clamped between end sections of said fastening member and said peripheral edge portion of the cover.