초록 ▼

A power supply apparatus includes a power supply unit disposed within a casing. The power supply unit includes power semiconductor devices. A fan is provided in the casing for cooling the power semiconductor devices. The power supply unit is operated in a plurality of contiguous cycles each includin

A power supply apparatus includes a power supply unit disposed within a casing. The power supply unit includes power semiconductor devices. A fan is provided in the casing for cooling the power semiconductor devices. The power supply unit is operated in a plurality of contiguous cycles each including a running and pausing modes of operation. Each cycle lasting a relatively short time period. The power supply unit operates in the running mode and the pausing mode, respectively in response to the closing and opening of a start switch. In association with the closing and opening of the start switch, a switch for the cooling fan causes the fan to rotate and stop, respectively, which results in minimizing the difference between the highest and lowest temperatures of the power semiconductor devices so that the lifetime of the power semiconductor devices can be prolonged.

대표청구항 ▼

[ What is claimed is:] [1.]1. A power supply apparatus comprising:a casing;a power supply unit, including heat generating components including a power semiconductor device, disposed in said casing;a cooling fan disposed in said casing for cooling said heat generating components;a start switch, when

[ What is claimed is:] [1.]1. A power supply apparatus comprising:a casing;a power supply unit, including heat generating components including a power semiconductor device, disposed in said casing;a cooling fan disposed in said casing for cooling said heat generating components;a start switch, when closed, enabling said power supply unit to operate for a first predetermined time, and, when opened, disabling said power supply unit for a second predetermined time, the closing and opening of said start switch alternating with each other; anda timer responsive to the closure of said start switch for enabling said cooling fan to operate, said timer disabling said cooling fan a third predetermined time after the opening of said start switch, said third predetermined time being shorter than said second predetermined time during which said power supply unit is disabled.