GB1355088A - Liquid level responsive means - Google Patents

Abstract

1355088 Delivering measured quantities of liquid S B NAGY 15 June 1972 [16 June 1971] 28195/71 Heading B8N [Also in Divisions G1 and G4] A liquid metering arrangement comprises a tube 1 connected through a solenoid valve 17 to a liquid supply 19 there being disposed along the length and at opposite sides of the tube a series of lamps 23, 29...33 and photo-sensitive resistors 22, 24 ... 28. The lamps and resistors are so disposed that in the event of the radiation from the lamp passing through the liquid the beam is so refracted as to impinge on the photo-electric cell of the resistor (Fig. 1, not shown). Additionally a photo-sensitive resistor may also be operated in the absence of the liquid with the beam unaffected (Fig. 2, not shown). The lower resistors 24 ... 28 are coupled in parallel with coils 35, 36 operating coils 17<SP>1</SP>, 20<SP>1</SP> for inlet and outlet valves 17, 20 and relay contacts 35<SP>1</SP>, 35<SP>11</SP>, 35<SP>111</SP>. By operatively selecting an appropriate lower resistor 24 ... 28 by moving switch 34 the coil 35 is energized to operate relay contacts 35, 3511 to energize coil 17<SP>1</SP> and open valve 17 whereby liquid rises in the tube until the level causes the upper resistor 22 to become ineffective to maintain operation of coil 35 so that contacts 35<SP>1</SP>, 35<SP>11</SP> open and contacts 35<SP>111</SP> close. Solenoid valve 17 is thereby closed and the liquid level arrested. A push-button switch 37 of a second relay is then depressed to operate coil 36 and relay contacts 36<SP>11</SP> are closed to energize operating coil 20<SP>1</SP> to open solenoid valve 20. Simultaneously contacts 36<SP>1</SP> are closed to complete a maintaining circuit through the contacts 35<SP>111</SP>. When the level of liquid falls below the location of the selected resistor 24 ... 28 the latter effects operation of coil 35 causing coil 36 to become deenergized and consequently the valve 20 is closed. By selectively setting the switch 34, different volumes of liquid corresponding to different lengths of the tube may be metered. Additionally for measuring fuel consumption the tube may be coupled to an engine 40 and the resistors 22<SP>1</SP>, 24<SP>1</SP> ... 26<SP>1</SP> incorporated in a logic circuit including a timer 56, Fig. 4, which is actuated as the fluid fuel in the tube passes down past the upper resistor 22<SP>1</SP> and ceases when the level passes the selected lower resistor. Consequently from the amount of fuel used in the time indicated the rate of consumption can be calculated.