| 摘要 |
<p>A chemical liquid feed pump capable of stabilizing the discharge of a chemical liquid by reducing the pulsation of a discharge pressure by a diaphragm and fine-controlling the discharge pressure. The opening (22d) of a supply/discharge passage (22b) is formed in the inner wall surface (22c) of a working chamber (26) (recessed part (22a)) at its center part, and a pin (24) projected to the diaphragm (23) side is mounted at a position offset from the center part. When the diaphragm (23) is deformed to the working chamber (26) side by the suction of an operation air into the working chamber (26) in sucking the chemical liquid, a part of the diaphragm (23) opposed to the pin (24) rides over the pin (24) and brought into a deformed state to the pump chamber (25) side in a slightly projected shape. When the operation air is supplied from the opening (22d) of the supply/discharge passage (22b) into the working chamber (26) in jetting the chemical liquid, the deformation is started preferentially at the portion of the diaphragm (23) riding over the pin (24).</p> |
