ide 63 and the elongated bar face 71. The air, after entering the recess 67, passes over the upper surface 53 of the belt and out a slot 73. By reason of the reduced dimensions of the slot 73 pared to the recess 69, a zone of higher pressure, e.g., greater than ambient pressure, is created above the belt surface 53. This zone of high pressure tends to force an edge portion of the belt toward the top plate 29. Thus, contact between the belt surface 53 and the underside surface 63 of the guide 57 is minimized or eliminated. This action is extremely significant when the belt is traveling at high speeds, greater than a 1,000 feet per minute and as high as about 2,200 feet per minute. Contact between the surfaces 53 and 63 at these high speeds could cause significant damage to the belt surface.
全文预览
