| 摘要 |
A ventilation passage formed to penetrate between the upper and lower surfaces of a movable grating and a fixed grating comprises a rear ventilation passage disposed in the rear of the movable and fixed gratings, and a front ventilation passage disposed in front of the movable and fixed gratings. At least the upper end side of the rear ventilation passage is formed in the direction perpendicular to the upper surface and at least the upper end side of the front ventilation passage is formed to incline forward with respect to the upper surface. Supply air can thereby touch a matter being processed located in the rear of the movable and fixed gratings while preventing the supply air from flowing through and preventing a mass of the matter being processed from being caught by the movable and fixed gratings, and cooling/protective effect of the supply air is enhanced in the rear of the movable and fixed gratings. |
