Fuel Injection Pump

Abstract

A fuel injection pump for a diesel engine, including: a control rack an in a rack chamber formed between a pump head and a pump housing, and configured to adjust a fuel injection amount; a transmission shaft rotatably supported by a transmission shaft hole formed in the pump housing; and a lubricating oil passage formed in the pump housing, and configured to pressure-feed lubricating oil between the transmission shaft and the transmission shaft hole. The transmission shaft has an oil passage therein through which passage the lubricating oil pressure-fed to the lubricating oil passage partially passes, a first opening of the oil passage is communicated with the lubricating oil passage, and a second opening of the oil passage is formed on the outer circumferential surface of an upper portion of the transmission shaft, nearby the control rack.

What is claimed is: 
     
         1 . A fuel injection pump to be provided in an engine, comprising:
 a transmission shaft supported by a pump housing,   wherein the transmission shaft includes:
 an oil passage, 
 and 
 an opening of the oil passage, wherein said opening is formed on an outermost circumferential surface of an upper portion of the transmission shaft. 
   
     
     
         2 . The fuel injection pump to be provided in an engine according to  claim 1 , further comprising:
 a lubricating oil passage formed in the pump housing, wherein the lubricating oil passage and the oil passage communicate through another opening separate from said opening.   
     
     
         3 . The fuel injection pump according to  claim 2 , wherein the oil passage includes:
 a groove formed in the outer circumferential surface of the transmission shaft in an axial direction thereof, the groove including said another opening;   a communication path opened on a wall portion of the groove, and formed in a radial direction of the transmission shaft; and   a supply hole communicated with the communication path and formed from substantially an axial center portion of the transmission shaft to said opening.   
     
     
         4 . The fuel injection pump according to  claim 3 , wherein the groove has at least one side wall formed perpendicularly to the wall portion. 
     
     
         5 . The fuel injection pump according to  claim 4 , wherein a lower end portion of an open portion of the groove is formed in a substantially U-shape. 
     
     
         6 . The fuel injection pump according to  claim 2 , wherein the second opening is formed in a recess of an upper edge of the transmission shaft. 
     
     
         7 . The fuel injection pump according to  claim 3 , wherein the first opening is defined by an overlap of a bottom portion of the groove and the lubricating oil passage.