Electromagnetic shielding apparatus for a memory storage disk module which permits air flow for cooling

A memory storage disk module comprising:

• a memory storage disk unit including at least one memory storage disk, and at least one head able to access the disk for writing and reading data to and from the disk;
• a control circuit board attached to the memory storage disk unit and including a control circuit for controlling the disk and the head;
• a shielding cover covering at least said memory storage disk unit and said control circuit board and having means for shielding electromagnetic waves emitted from at least said control circuit board, said cover having a longitudinal axis, a main panel portion extending generally along and around the longitudinal axis and having opposite ends, a front panel portion located on the main panel portion at one end thereof, and a rear panel portion located on the main panel portion at the other end thereof, the main panel portion being substantially solid and the front and rear panel portions having small apertures, respectively, allowing air to flow therethrough and directly over said memory storage disk unit and said control circuit board, while shielding electromagnetic waves emitted from at least said control circuit board;
• and
• a cooling fan arranged in said cover at a location having a first cross-sectional area so that air flows through a region between said memory storage disk unit and said control circuit board for cooling said memory storage disk unit and said control circuit board, said region having a second cross-sectional area, said first cross-sectional area being larger than said second cross-sectional area, said control circuit board being arranged parallel to the flow of cooling air.