Patent GB-668638-A (GB)
Title: Improvements in or relating to gas-turbine power-plant installations
Inventor: LOMBARD ADRIAN ALBERT
IPC: F02C7/055
Filed: 1949-04-28
Abstract: 668,638. Gas turbine plant; axial flow compressors. ROLLS-ROYCE, Ltd. April 26, 1950. [April 28, 1949] No. 11378/49. Classes 110(i) and 110(iii). [Also in Group XXXIII] A gas turbine power plant has a guard grid formed from a plurality of grid panels arranged for movement between an operative position in which the panels form a substantially continuous grid across the air intake and a retracted position in which the air passage is substantially unobstructed by the grid panels. The guard grid, Figs. 1 and 2, comprises a number of panels 16 which are movable between the operative position shown and a retracted position in which they are .accommodated within recesses 17 formed in the outer wall 10a of the gas turbine air intake 10. Each panel 16 consists of a channel section frame 16d for supporting the grid and is shaped as a portion of a surface of a cylinder so that in its retracted position it conforms to the shape of the outer wall 10a. The grid is formed from strip metal in honeycomb form sweated or brazed into the frame 16d. Each hexagonal orifice is arranged in line with the air flow so that a stepped effect is formed between the strips 71, Fig. 9. The panels 16 are supported from cross shafts 18 carried in bearing brackets 19 forming part of a supporting ring 20 bolted to the front flange 14a of the compressor casing 14. The cross shafts extend circumferentially around the ring 20 and are interconnected by sector gears 21 so that 'the panels 16 move together. The shafts 18 are rotated by a ram 24 through a piston rod 24a and radius arm 25. To catch the debris as the panels 16 are moved to the retracted position a metal strip is welded to the channel frame 16d to form lips 16e. A series of imperf orate panels 26 blank off the mouths of the recesses 17 when the panels 16 are in the operative position. The pariels 26 are pivoted at one end to the wall 10a and carry a pin 35 which engages a slot 31a in an operating arm 31. The arm 31 is actuated through toothed members 28, 29 and 30 from the shaft 18. The rearward edge 26a of the panels 26 is stepped so as to engage a sealing strip 36 on the nacelle skin 27 and thus form a debris chamber 37 when the panels 26 are retracted. In a modification, Figs. 4 and 5, the panels 16 are pivoted on two levers 45, 46 universally mounted on girder members 40 by ball and socket joints 48, 49 so that the panels 16 rock about an axis which is a chord of the duct 10. The levers 45 are actuated by rams 53 the action of which is co-ordinated by connecting them to a common pressure fluid supply. The recesses 17 are blanked off by a number of panels 58 each of which is in two parts 58a, 58b, united by a doubledished bridge piece 59. The panels 58 are pivoted on pins 62 which engage bosses 51 on levers 45, 46 and pins 64 which are connected to swinging links 60. When the rams 53 are operated to swing the panels 16 from the operative position, the levers 45, 46 and links 60 cause the panels 58 to be lifted out of the recesses 17 and swung rearwardly.