Heat sink unit, circuit board unit, and electronic device

A circuit board unit comprising:

• a circuit board;
• a heat-producing electronic component which is mounted on the circuit board and produces heat by consuming electric power;
• and
• a heat sink unit which is fixed to the circuit board and emits the heat produced by the heat-producing electronic component,
• wherein the heat sink unit comprises:
• a cooling member including a metal plate having a plurality of attachment holes on edges thereof, a first surface of the metal plate adjoining a heat-producing electronic component, and a second surface of the metal plate having a plurality of cooling fins erected on an area other than the attachment holes;
• an attachment member including an opening in which the cooling fins are disposed when the cooling member is installed and a plurality of threaded bosses protruding from the first surface to be inserted into each of the attachment holes;
• and
• coil springs into which the bosses are respectively inserted, and
• wherein the coil springs are interposed between the attachment member and the metal plate, and the bosses are inserted into the attachment holes to fix the cooling member by screws.

An electronic device comprising:

• a circuit board unit;
• and
• a casing which stores the circuit board unit,
• wherein the circuit board unit comprises:
• a circuit board,
• a heat-producing electronic component which is mounted on the circuit board and produces heat by consuming electric power, and
• a heat sink unit which is fixed to the circuit board and emits the heat produced by the heat-producing electronic component,
• wherein the heat sink unit comprises:
• a cooling member including a metal plate having a plurality of attachment holes on edges thereof, a first surface of the metal plate adjoining a heat-producing electronic component, and a second surface of the metal plate having a plurality of cooling fins erected on an area other than the attachment holes,
• an attachment member including an opening in which the cooling fins are disposed when the cooling member is installed and a plurality of threaded bosses protruding from the first surface to be inserted into each of the attachment holes, and
• coil springs into which the bosses are respectively inserted, and
• wherein the coil springs are interposed between the attachment member and the metal plate, and the bosses are inserted into the attachment holes to fix the cooling member by screws.