GB831177A - Centrifugal governor - Google Patents

Abstract

831,177. Centrifugal governors. CATERPILLAR TRACTOR CO. May 19, 1958 [March 10, 1958], No. 15954/58. Class 57. A centrifugal governor for positioning the fuel control rack bar 24 of an internal combustion engine comprises flyweights 11 loaded by a spring 23, a control rod 28 connected to the rack bar, and a control lever 35 operable in one direction to preload the spring 23 and operable in the other direction to engage the rod 28 and position the rack bar. The flyweights are pivotally mounted on a carrier 12 driven through gearing 16, 17 from an engine driven shaft 18 and actuate a thrust member 22 to move an adaptor 27 secured to the rack bar against the spring 23. The control rod 28 is axially slidable in a bearing 29 and is formed at one end with a flange 46 providing a lost-motion connection with the adaptor 27 and carries at its other end an enlarged plate member 51. The control lever 35 comprises two bell-crank levers 36, 37 that are connected by a sleeve 38 secured to a shaft 39 rotatably journalled in the governor housing 30 and have tail portions 65 joined by a member 69 carrying a spring- loaded detent 71 adapted to engage a low idle stop cam surface 61 on an axially adjustable bolt 62. A manually-operable lever 41 is fixed to the shaft 39 outside the housing 30. The spring 23 is compressed between the adaptor 27 and a spring seat 32 slidably mounted on the bush 29 and under normal operating conditions the lever 35 abuts the seat 32 and rotation of the shaft 39 clockwise increases the spring preload until member 69 contacts an adjustable high idle stop member 81 screwed into the housing 30. When the lever 35 is moved counter-clockwise it first progressively releases the load on the spring 23 and then passes through slots 53 in the housing 30 to contact the plate 51 and positively move the rack bar to the engine shut-off position as indicated by broken lines at 54. During counterclockwise movement of the lever 35 the detent engages the surface 76 of cam 61 to indicate to the operator that the governor is set in low idle condition. Further such movement causes the detent 71 to pass over the high point of the cam and the detent spring 72 then urges the lever 35 to the shut-off position. The bolt 62 and member 81 are locked in their set positions by a common locking cap 83. Buffer springs 58 and 59 are provided for the adaptor 27 and plate 51 respectively.