GB338236A - Improvements in or relating to governing means for steam turbines or other engines - Google Patents

Abstract

338,236. Baumann, K., Jolley, J. E., and Associated Electrical Industries, Ltd. Aug. 26, 1929. Centrifugal governors; fluid relays.- In a means for governing a steam turbine or other engine, a centrifugal governor operates in conjunction with a fluid relay to operate the throttle valve in such a manner that movement off the valve is proportional to the position of the governor spindle and hunting is eliminated. Fig. 1 shows the pilot valve 9 attached to the governor spindle 10 and operating in a sliding ported sleeve 12. The pilot valve controls the flow of pressure fluid from a pump 34 to two pressure relay devices which comprise spring controlled pistons 1 and 1<a> operating in ported sleeves 3 and 3<a> which in turn are contained in ported cylinders. The ported sleeve 3 is provided with a piston 5 and controlled by the spring 4 and also conected to a pivoted link 8 which is also attached to the ported sleeve 12 of the pilot valve. The sleeve 3<a> is attached to a pivoted lever 20, to which is also attached the throttle valve 19 and the power cylinder 24 for operating same. The operation is as follows :-Upon a decrease of speed, the pilot valve 9 falls and permits pressure fluid to flow to chambers 22 and 23. The piston 1 rises against its spring control and permits a flow of pressure fluid from pipe 35 through ports 3<b> to the underside of the piston 5. The sleeve 3b then rises and following the movement of piston 1 again tends to close the ports 3<b> and moves the sleeve 12 in a direction to close the ports 12<a>, equilibrium being reached when the movement of the piston 1 is proportionally the same as that of the pilot valve. A similar action takes place in the second relay, the piston 1<a> allowing the flow of fluid to the power cylinder and the movement of the power piston causing the sleeve 3<a> to follow up and close the ports. For an increase in speed the reverse action takes place wherein the ports communicate with the escape drains 25, 25<a>. The speed at which the governor operates may be adjusted by moving the pivot 11, so adjusting the mean position of the sleeve 12. Modifications are described in which the pilot valve may be connected to an intermediate point in the link between the governor spindle and the first relay sleeve, and in which the ported sleeve 3<a> is replaced by a separate pilot valve.