GEAR TO ESTABLISH SURFACE TENSION IN LIQUIDS Russian patent published in 2004 - IPC

FIELD: instrumentation, aids testing surface tension of liquid media. SUBSTANCE: gear includes flow-type chamber, source of constant pressure feeding gas, pneumatic unbalanced bridge comprising tee-joint to which inlets of two throttles and outlet of feeding gas line are connected, two calibrated capillaries of different flow sections and same length joined to outlets of throttles, and differential manometer connected to measurement diagonal of unbalanced bridge and recording instrument connected to outlet of differential manometer arranged vertically in flow-type chamber. Gear is supplemented with additional pneumatic vessel, variable throttle, generator of rectangular pressure pulses and three-membrane pneumatic relay with fixed initial position incorporating make and break pneumatic contacts and control chamber. Outlet of source of constant pressure feeding gas is connected to make pneumatic contact of pneumatic relay, break contact of the latter communicates with atmosphere. Control chamber of pneumatic relay is connected to outlet of generator of rectangular pressure pulses and outlet of pneumatic relay is coupled to inlet of variable throttle which outlet is connected to pneumatic vessel and inlet of feeding gas line. EFFECT: simplified design and increased accuracy of gear for automatic establishment of surface tension in liquids. 2 dwg