GB442705A - Improvements in and relating to governing mechanism for elastic fluid engines - Google Patents

Abstract

442,705. Fluid-pressure servomotorcontrol systems. BRITISH THOMSONHOUSTON CO., Ltd., Crown House, Aldwych, London. May 1, 1935, No. 13025. Convention date, May 3, 1934. [Class 135] A governing mechanism for elastic-fluid engines including speed-correcting means of the type disclosed in Specification 262,133, [Class 135], and 361,537, [Group XXVI], is provided with means for accelerating the operation of the correcting means in response to sudden increases in speed to prevent the emergency trip operating. The speed governor 27 operates a pilot valve 24 controlling the supply of pressure fluid to a servo-motor 16 which through the lever 14 pivoted about the point 29 actuates the admission valve 11 of the engine or turbine 10, and also the follow-up sleeve 22 of the pilot valve 24. The lever 14 through linkages 43, 42 and 41 operates a second pilot valve 40 controlling a servo-motor 30 which constitutes a speedcorrecting means and moves the valve 11 farther to correct the speed through the lever 14, which now pivots about its connection to the rod 15 of the servo-motor 16, and at the same time restores the sleeve 22 of the main pilot valve 24 to its original position, the pilot valve 24 also assuming its original position as the speed correction takes effect. In the event of a sudden increase of speed, this correcting mechanism may not act sufficiently fast and to accelerate its action a valve 46 is provided in a conduit leading to the servo-motor 30 which is operated by links 43, 42, and 50 from the lever 14 to supply pressurefluid direct to the servo-motor in addition to that past the pilot valve 40. The link 43 is adjustable along the lever 14 to adjust the amount of correction of the servo-motor 30 for either zero, positive, or negative regulation of the speed. Specification 422,579, [Group XXVI], also is referred to.