US PATENT SUBCLASS 169 / 22
.~.~ Differential area


Current as of: June, 1999
Click HD for Main Headings
Click for All Classes

Internet Version by PATENTEC © 1999      Terms of Use



169 /   HD   FIRE EXTINGUISHERS

19  DF  AUTOMATIC VALVES {1}
20  DF  .~ Pressure controlled {2}
22.~.~ Differential area


DEFINITION

Classification: 169/22

(under subclass 20) Apparatus, wherein the pressure of the fluid in the distributing- pipes is transmitted directly from the air-valve to the water-valve to maintain the latter closed, the effective area of the air-valve being greater than that of the water-valve. The air-valve may be integral with the water-valve or may have a bearing upon it without the interposition of levers, toggles, or the like.