| 摘要 |
PURPOSE:To improve durability of a plunger by arranging a partition wall encapsulating pressure transmission fluid in a fluid path in front of the top dead point of the plunger such that it will partition into plunger side, suction and delivery valve body sides. CONSTITUTION:Upon reciprocal sliding of a plunger 14 through rotary driving of a crankshaft, lubricant in a cylinder 13 is compressed to increase pressure of fluid in a fluid path 12 through an elastically deformable partition wall 23 encapsulating pressure transmission fluid, and thereby a suction valve body 19 closes to deliver fluid in the fluid path 12 through a delivery valve body 22. When negative pressure is produced in the cylinder 13 due to returning motion of the plunger 14, the delivery valve body 22 closes to suck fluid through the suction valve body 19 into a partition wall section 23. By such arrangement, abrasion of the plunger 14 and the cylinder 13 due to a solid mass can be prevented, and since pressure functioning onto the plunger 14 is relieved through the partition wall 23 even when the pressure of the fluid is abnormally high, durability of driver is improved. |
