| 摘要 |
PURPOSE:To realize the smooth actuation of a downward blow damper by a structure wherein the downward blow damper is opened and closed by the gearing action of rack and pinion and yet the uppermost side of a keep plate is rendered to be brought into contact with the circumference of the pinion. CONSTITUTION:The variable driving unit of a downward blow damper 7 to change the blowoff air direction consists of a pinion 8, a rack 10 and a keep plate 16. Flanges 17 and 18, which are bent toward the tooth profile 11 side of the rack, are integrally formed at both ends of the tooth profile 11 side of the rack together with a handle 14, which drives the rack 10, formed at the side opposite to the tooth profile 11. Furthermore, tooth profiles are formed over one-fourth of the circumference of the outer circumferential surface of the pinion 8 and as well as one side of the keep plate 16 is on the circumference of the pinion 8, while its other side is placed on the plane surface at the tooth profile 11 side of the rack. In addition, when the rack 10 is driven to open the damper 7, the circumferential surface of the pinion 8 abuts against the flange 18 and when the rack 10 is driven to close the damper 7, the tip of the keep plate 16 abuts against the flange 17 of the rack 11. In other words, the flanges 17 and 18 serve as the stopper at the opening and the closing of the damper 7 respectively. |
