| 摘要 |
PROBLEM TO BE SOLVED: To provide a high pressure fuel pump enabling expansion of a tolerance range of a clearance between a cylinder and a plunger in the plunger type high pressure fuel pump and enabling increase of productivity. SOLUTION: In the plunger type high pressure fuel pump 1 provided with a plunger 23 inserted in the cylinder 21 in such a manner that the same can slide and reciprocate in the cylinder 21, and repeating suction of fuel into a pressurizing chamber 22 and pressurization/delivery of fuel in the pressurizing chamber 22 by reciprocating motion of the plunger 23, linear expansion coefficient of the material constructing a plunger 23 is set smaller than linear expansion coefficient of the material constructing the cylinder 21. The clearance between the plunger 23 and the cylinder 21 increases proportionally to rise of cylinder/plunger temperature by setting liner expansion coefficient of the plunger 23 small in this way. Consequently, the clearance at high temperatures can be set large as compared to the clearance at low temperatures, and tolerance range of the clearance can be expanded. COPYRIGHT: (C)2008,JPO&INPIT
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