GB799170A - Improvements in fuel control valve devices - Google Patents

Abstract

799,170. Clockwork actuated valves. ROBERTSHAW - FULTON CONTROLS CO. May 7, 1956 [Aug. 16, 1955], No. 14079/56. Class 135. A fuel control valve comprises two valve members the actuating means of which is controlled by timing mechanism and manually operable setting means. One. valve member controls the inlet to a casing having two outlets one of which is controlled by the other valve member. The device comprises a casing 10, Fig. 1, divided into three chambers 16, 20 and 50. A closure member 34 urged to a closed position by a spring 38 controls a passage 30 which interconnects chambers 16, 20. The hollow stem 42 of the closure member 34 is guided by a centring pin 44. The interconnecting passage 58 between chambers 50 and 16 is controlled by a closure member 62 similar to closure member 34. The valve stems 42, 64 have adjustable nuts 48, 69 which engage opposite ends 74, 77 of a centrally pivoted lever 70. The relative strengths of springs 38, 66 are such that the closure members and the lever 70 are urged to the position shown in Fig. 1. The lever 70 is controlled by actuating means comprising a spindle 78 located in a recess 90 and urged outwardly by a spring 84. The outer end of the spindle 78 is recessed to receive a plunger 96 located in a housing 98 secured to the casing 10. The plunger 96 is loosely retained in a shaft 100 rotatable relative to the housing 98 by a knob 102. A plate 106, Fig. 2, having diametrically opposed projections 108, 110 is fixed to shaft 100 and co-operates with a stepped cam 118 secured to the housing 98. The cam 118 has opposed pairs of helical surfaces 120, 122 and 124, 126 separated by walls 128, 130 two diametrically opposed recesses 132, 134 and two stops 136, 138. Guide plates 137 extend from a plate 135. The projections 108, 110 are normally in the recesses 132, 134 respectively to hold the lever 70 and the closure members 34, 62 in the positions of Fig. 1. In operation the knob 102 is depressed to move the spindle 78 and rock the lever 70 counter-clockwise to the position shown at A, Fig. 1. The knob 102 is then rotated whereupon the projections 108, 110, Fig. 2, ride along the guide plates 137 and finally drop on to the cam surfaces 120, 124 and move to abut the stops 136, 138. The closure members 34, 62 assume the positions B and C so that fuel flows from inlet 12 into the chamber 20 through the passage 30 into the chamber 16 through the outlet 14 to the after burner. The rotation of the knob is transmitted to the mainspring of a clockwock 140 which returns the plate 106, shaft 102 and the knob 102 to their original positions. During this return movement the projections 108, 110 ride the cam surfaces and the lever 70 is moved successively through the positions F, L and Q. The closure member 34 moves through the positions H, N and R to the closed position whereas the closure member 62 moves from the closed position through the positions M and S to the position shown. It can be seen therefore that starting from the setting in which fuel flows only from outlet 14 the closure members 34, 62 move to positions in which fuel flows from inlet 12 out of both outlets 14 and 18 and finally to a position in which the passage 30 is closed so that no fuel passes through the outlets 14 or 18.