| 摘要 |
<p>740,099. Valves. AKTIEBOLAGET SVENSKA FLAKTFABRIKEN. Feb. 10, 1954 [Feb. 17, 1953], No. 3917/54. Class 135. A valve for maintaining a constant static pressure in a duct such as a ventilating duct comprises a curved valve plate 8 carried by arms 10, 12 fixed to a spindle 32 which is angularly movable by a flexible diaphragm 41 acting through a rod 24 guided by rollers 36a, 36b, a lever 17 pivoted at 16, and a link 22 connected to a lever 26 which is adjustably clamped to the spindle. Chambers 42, 45 on either side of the diaphragm are connected to two points in the system, e.g. to an air distributing duct and to a place to be air-conditioned. The pressure difference across the diaphragm is balanced by a spring 19 engageable with any one of a series of adjustment holes 20 in the lever 17. Alternatively, a weight may be used. An adjustable counterweight 27 is carried by an arm 29 clamped to the spindle 32. The spindle also carries a disc 25 which co-operates with a fixed pointer whereby the degree of opening of the valve can be observed through a window.</p> |
