Patent ID: 6912123

Claim:
A power supply device, wherein: a power supply circuit, which comprises a rectifier circuit for rectifying an AC current from a commercial AC power supply and a switching element provided on the output side of the rectifier circuit, is connected to a first primary side winding of a high frequency transformer; a secondary side DC output circuit, which supplies electric power to a load, is connected to a secondary side winding of the high frequency transformer; a second primary side winding of the high frequency transformer and a DC power supply circuit that is separate from the power supply circuit are provided with connecting portions that are capable of connecting and disconnecting the second primary side winding and the DC power supply circuit; a cooling fan for the release to the outside of heat generated within a casing that houses at least the power supply circuit, the first primary side winding, the secondary side DC output circuit, the secondary side winding, and the second primary side winding is detachably mounted in the casing; a protective member is mounted so as to be displaceable to a removal disabling position located in front of the cooling fan in order to obstruct removal of the cooling fan by abutting against same, and to a removal enabling position that is retracted from the position in front of the cooling fan in order to allow removal of the cooling fan; the protective member is constituted so as to be displaceable to the removal enabling position only when a switch provided on the casing is turned OFF in order to switch the cooling fan from ON to OFF, or only when an insertable/removable power supply cable plug that is inserted in an input portion provided in the casing in order to input the AC current from the commercial AC power supply is removed, or only when the switch is turned OFF and the plug is removed; a stopper member, which obstructs the movement of the protective member to the removal disabling position by abutting against the protective member in a state where the cooling fan is not disposed in a predetermined position in the casing, and which allows the movement of the protective member to the removal disabling position in a state where the cooling fan is disposed in the predetermined position in the casing, is provided.