| 摘要 |
<p>PROBLEM TO BE SOLVED: To eliminate the deterioration of outward appearance and also to prevent foreign matter from entering through vent holes in a configuration which utilizes the vent holes and controls the temperature rise in an outer case. SOLUTION: In the programmable controller 1, a groove part 11 for DIN mounting is formed between leg parts 12 formed on the bottom face of an outer case 2. Vent holes 16 are formed in the groove part 11 for DIN rail mounting and the positions of the vent holes 16 are corresponding to the corners of a printed circuit board provided in the outer case 2. Since heated air is discharged from the holes 16 located at an upper place and air simultaneously enters from the holes 16 located at lower place when an electronic part mounted on the printed circuit board generates heat, an air route passing through the printed circuit board is formed and the temperature rise inside the controller 1 can be suppressed.</p> |
