GB1339089A - Device for indicating changes in the density of a liquid - Google Patents

Abstract

1339089 Measuring density POLYGRAPH LEIPZIG KOMBINAT FUR POLYGRAPHISCHE MASCHINEN UND AUSRUSTUNGEN VEB 6 April 1972 15922/72 Heading G1S A cylindrical float 1, Fig.1 contains a second float 3 and traps it in the cavity 2 by means of a diaphragm 4 and a strip 16 mounting adjustable compensating floatation weights 18. A vent tube 15 connects the cavity 2 with the atmosphere so that the liquid supporting the floats has a level a around the float 1 and a level c around the float 3, the air in the space between 3 and 4 depressing the level to c. A casing 5 supports a three leaf electric switch 7 operated by the float 3 pressing on the diaphragm 4, and a piston 13 may be moved to increase or decrease the air pressure in the casing 5 to affect the operation of the diaphragm 4 and vary the density tolerance range. In Fig.2 the piston 13 is not provided and the contacts of 7 are adjusted by turning a screw 19. In operation the apparatus is floated in a liquid and adjusted so that its contact 8 is in a middle position. If the liquid density varies then there is relative vertical movement between the floats 1, 3 and the contact makes either one leaf or the other of the switch 7 to indicate on two signal lamps the raising or lowering of the density, Fig.3 (not shown) or to arrange for relays and magnetic valves to be operated and make provision for the liquid to be either automatically diluted or strengthened, Fig.4 (not shown). In a modification the electric switch can be replaced by pneumatic controls or by micro-switches or tilting mercury switch tubes. It is also possible to provide magnetic contacts in the casing 5 operated by a magnet across the diaphragm.