| 摘要 |
Provided is a pump device capable of minimizing a decline in pump efficiency. A pump device equipped with: a venturi section provided partway along a discharge channel, and having a small-diameter section having a smaller inner diameter than the inner diameter of the discharge channel from the discharge port to the venturi section, and a gradually increasing inner-diameter section formed in a manner such that the inner diameter thereof gradually increases from the small-diameter section toward the downstream side of the discharge channel; and a control valve to which the pressure inside the venturi section and on the upstream side of the venturi section is introduced, and which controls the flow of a working fluid supplied to an automatic transmission by switching the working fluid channel on the basis of the difference in the pressure inside the venturi section (50) and on the upstream side of the venturi section. |
