| 摘要 |
1296058 Gas turbine engine fuel systems BENDIX CORP 18 Nov 1969 [18 Nov 1968] 56472/69 Heading F1G [Also in Division G3] A fluid system controlling the fuel supply to a gas turbine has a bridge circuit in which when one limb is unbalanced by changes in engine speed from a predetermined value a servomotor adjusts the other limb to rebalance the bridge and simultaneously adjusts the fuel supply to correct the engine speed. Engine 112 is fed from tank 118 by gear pump 120 and line 116 via an orifice 126 controlled by a piston 98a secured to a piston 38a, movement of which varies the impedance 134 in line 144. Further impedances 96b, in a piston 38b are respectively in series with impedance 134 and a manually controllable valve 189 which is used to pre-set the engine speed. A vortex device 162 as described in Specification 1182547 generates a signal P n proportional to engine speed and this is fed into control ports 60a, 62b of proportional amplifiers 46a, 46b, the other control ports 62a, 60b of which are respectively fed with a pressure P f determined by the adjusted position of impedances 96b, 134, and a pressure P t determined by the settingof valve 189 and the position of piston 38b. The power outlets of amplifiers 46a and 46b adjust the pistons 38a, 38b, 98a to control the fuel supply to maintain a pre-set engine speed. |
