| 摘要 |
PROBLEM TO BE SOLVED: To dissipate the heat of a circuit element attached to a circuit board by means of a heat dissipation member attached to the circuit board.SOLUTION: A motor drive unit 34 includes a circuit board 18 constituting a part of a control circuit for controlling rotation of a motor, a circuit element 16 constituting other part of the control circuit, and a heat sink 20 attached to the circuit board 18. The heat sink 20 is formed using an insulating material, and a plurality of protrusions and recesses 54 are formed on the circuit board 18 side of the heat sink 20. The heat sink 20 is attached to the circuit board 18 in contact with the circuit board 18, in a state where a gap formed between the circuit board 18 is filled with an insulating heat dissipation material 60. Consequently, the heat of the circuit element 16 attached to the circuit board 18 can be dissipated by means of the heat sink 20 attached to the circuit board 18.SELECTED DRAWING: Figure 6 |
