| 摘要 |
<p>A blowing device with blowing nozzle for emitting a concentrated, aimed pressurized air jet and incorporating a feed channel (7) having at least one slot-formed exhaust passage (3), which determines the flow quantity through the blowing device. The purpose of the invention is to create a concentrated air flow, well adapted for cleaning, preferably in the component producing industry, having low noise generation at the object blown upon, within the mixing zone and also at the exhaust opening, at critical as well as particularly at sub-critical flow. This is obtained with the blowing device according to the invention in that the exhaust passage or passages (3) is/are constituted by a number of very thin, relative to their width elongated slots (4) located around a common slot center portion, that the ratio between the smallest slot length (L) and the biggest slot width (B) is bigger than 5, preferably bigger than 12, that the most narrow section of the exhaust passage/passages (3) is situated inside the end plane (2) of the nozzle, thus that the expansion zone for the pressurized gaseous fluid is situated outside the end plane (2) of the nozzle and that the extension of the slots (4) in the direction of flow is such that the dynamic pressure of the jet of air, at escape of pressurized gas at critical flow velocity, e.g. air of a feed pressure of 6 bar and the temperature 293 DEG K, by adiabatic expansion, during its exit to the surroundings, is higher than the atmospheric pressure, preferably considerably higher.</p> |
