PURPOSE: To suppress the abrasion of a rod which is vertically moved and rotationally moved, and improve the durability of a very small discharge quantity pump by forming the pump so as to nearly equalize contact force which acts on a rod at the intake time when a fluid chamber is expanded, and a contact force which acts on a rod at the discharge time when the fluid chamber is contracted.
CONSTITUTION: In a body 1, a notch part 6 which extends in an axial direction and is opened to a fluid chamber 8, is formed at the top end part of a rod 5 whose one end is inserted from the other end side in a closing inserting hole 2, and an intake passage 3 and a discharging passage 4 are formed on a body at a position which is communicated with the notch part 6. In the roller 28 which is supported on the upper part of the rod 5, the rod 5 is vertically moved and rotated by rotating it along a cam surface 7 having a step difference part formed on the upper end surface of the body 1, and fluid is discharged. In this case, the center axis of the roller 28 and a straight line faced from the center axis of the rod 5 to the center of the notch part 6 are set to an angle of nearly 90°, and smooth operation in which large contact force is not activated is realized.
TSUCHIDA TOSHIYUKI
MORI MICHIHIRO
