Patent ID: 7234738

Claim:
A casing assembly comprising a casing defining a receiving space, having inner and outer surfaces, a retention hole formed through said inner and outer surfaces, and an entrance for access into said receiving space in said casing; a lid mounted within said entrance in said casing to deny access into said receiving space in said casing; and a fastening device including two positioning plates mounted stationarily on said inner surface of said casing in such a manner that said positioning plates extend radially from said retention hole to define an angle therebetween, a rotary member enclosed within said casing and extending into said retention hole in said casing, said rotary member having an inner end, an outer operating end exposed from said outer surface of said casing, a blocking plate extending radially from said inner end, and a restricting plate extending radially from the inner end into said angle between said positioning plates, and a resilient clip disposed within said casing, and having a looped portion, a coupling strip extending from one side of said looped portion and fastened securely to said casing, and an urging strip extending from the other side of said looped portion for urging said restricting plate to rotate in a first direction so as to press against one of said positioning plates, which, in turn, rotates said blocking plate toward said entrance to abut against said lid, thereby preventing removal of said lid from casing, whereby, rotation of said outer operating end of said rotary member in a second direction opposite to said first direction against urging action of said resilient clip results in rotation of said restricting plate in said second direction so as to press against the other one said positioning plates, thereby permitting removal of said lid from the casing.