| 摘要 |
PURPOSE:To reduce the load applied onto an oil seal by setting nearly equal to pressure of the lubricating oil supplied into an oil resevoir formed onto the outer periphery of a drive shaft to the pressure of the fuel supplied into the space between the oil seal on one side and a feed pump. CONSTITUTION:The fuel pressurized by a feed pump 101 is pressure-adjusted by a regulating valve 120 and introduced into a pump mechanism chamber 109, and at the same time leaks into the left-side space 112 of the pump 101. The leaked fuel is introduced into the suction side of the pump 101 through a passage 104. At this time, the intrusion of the fuel in the space 112 into a bearing 102a side is suppressed by an oil seal 103a. While, lubricating oil intrudes into an oil reservoir 105 from an introducing passage 113 through a throttle 111, and lubricates journal bearings 102a and 102b. Though, in this case, the intake negative pressure of the fuel and the discharge back-pressure of lubricating oil act onto the both sides of the oil seal 103a, each of which is low pressure close to the atmospheric pressure, and a prescribed purpose can be achieved. |
