| 摘要 |
PURPOSE:To prevent interchanging of air between two adjacent chambers, by a method wherein extra air, being enough to lift a neutral band at an opening time of a door part to an upper end of the opening of the door part, is supplied to a positive pressure side, and a resistance, which maintains a given difference in pressure between the two chambers at the closing time of the door part, is mounted. CONSTITUTION:A prechamber 11 is mounted between a breeding chamber 10 and a corridor 12, while the breeding chamber 10 and the corridor 12 are designed to be set to a positive pressure of 2mm.Aq, and the prechamber 11 to be set to a negative pressure of -2mm.Aq. In a normal condition, a neutral band, having no difference in pressure, is formed in the middle in a vertical direction of an opening part resulting from the occurrence of a temperature difference between the breeding chamber 10 and the prechamber 11 produced with the opening of a door part 13. However, the neutral band disappears by applying an air amount, which is enough to lift the neutral band to the upper end of the opening of the door part, to the breeding chamber 10 at the positive pressure side. A connection opening, having resistance, for example, a nozzle orifice 17 is located at the boundary between the two chambers 10 and 11 to maintain a given difference in voltage. |
