GB816433A - Apparatus for testing the pneumatic governors of the fuel pumps of compression ignition engines - Google Patents

Abstract

816,433. Testing pneumatic governors. HARTRIDGE Ltd., L. Dec. 22, 1955 [Sept. 22, 1954], No. 27447/54. Class 57. Apparatus for testing the pneumatic governors of the fuel pumps of compression ignition engines comprises a U-tube 2, 3, 4 inclined to the horizontal and containing mercury, a scale 10 adjacent to the limb 3, and means for lowering the air pressure in the limb 3 and in the vacuum chamber of a governor to be tested. The air pressure may be lowered by a hand pump 13 or by an aspirator 14 according to the setting of a two-way valve 23 which is connected to a mercury trap 8 at the upper end of the limb 3 by tubing 24, an isolating valve 25 and a connection 21 with the governor. The aspirator may consist of an air discharge nozzle arranged concentrically with a venturi tube. The nozzle is connected by pipes 15, a regulating valve 17 and a shut-off valve 16 to a compressed-air supply 18 while the space between the tube and the nozzle is connected by a pipe 20 to the valve 23. An indicating device is applied to the fuel pump control rod and the air pressures checked at the " nearly closed " and " full open " positions. A " vacuum " test may be made by noting the time taken for a specified decrease in vacuum in the governor chamber. The scale 10 is secured by screws 11 passing through slots 12 so that the zero line on the scale may be adjusted. The U-tube is preferably -inclined at 60 degrees to the vertical so that a change in pressure of one inch of mercury corresponds to a distance of one inch on the scale 10. A spirit level 26 is provided.