GB454982A - Improvements in or relating to flow proportioning means - Google Patents

Abstract

454,982. Distant - control systems. REINEKE, J. H., 26, Castroperstrasse, Bochum, Germany. June 18, 1935, No. 17492. [Class 40 (i)] [See also Group XXIX] A flow-proportioning apparatus for use in connection with gaseous mixture (e.g. a mixture of coke oven gas with blast furnace gas) is arranged so that the quantity of a third gas (e.g. air) is made dependent on the quantity and proportions of the gaseous mixture. The Figure shows a fluid pressure servomotor system for effecting this control. The conduits 5, 6 conveying the constituents of the mixture are each provided with an orifice plate 8, the pressures on each side of which are arranged to act on the opposite sides -of a pair of diaphragms 12, 13 coupled together by a lever 21 pivoted on a movable fulcrum 24. The lever 21 is coupled by a link 25, lever 26 and spring 28 to an auxiliary valve 20 controlling doubleacting piston 31 coupled by a flexible link 32 to a slidable member 33 carrying the fulcrum 24. The arrangement is such that any unbalance of the pressures on the diaphragms occasioned by variation of the flow in either of the conduits 5, 6 causes the piston 31 to operate in the direction to adjust the fulcrum to restore the balance. The piston 31 also acts through a flexible link, pulley 61 and cam 59 to adjust the fulcrum 55 of a similar servomotor device controlled by the flows in the conduits 2, 3 conveying the gaseous mixture and air supply respectively, whereby the piston of this servomotor system adjusts the position of a throttle valve 52 in the air supply conduit both in accordance with the total flow of the mixture and the flows of the individual constituents. In a modification, the diaphragms 12, 13 are replaced by a pair of manometer U-tubes fitted with resistance devices comprising a series of contact rods of different lengths contacting with mercury in the tubes. These resistances are connected in circuit with a Kelvin balance or other balancing device or relay, a variable resistance operated by the piston 31 being included in the circuit to restore the balance when the flows in either of the two conduits 5, 6 vary. In a modification of this form a reversible electric motor coupled to a pinion, rack and flexible link by the pulley 61 replaces the piston 31. Specification 440,342, [Group XXIX], is referred to.