Flow-rate adjustable valve

A flow-rate adjustable valve for adjusting a flow rate of liquid flowing through a flow path, the flow-rate adjustable valve comprising:

• a main valve body movably supported in the flow path via an elastic member,
• a back pressure chamber in which liquid supplied from an upstream side of the flow path at a predetermined pressure is contained and a biasing force is generated in a valve-closing direction for closing the main valve body by the supplied liquid,
• an inlet hole communicating the upstream side of the flow path with the back pressure chamber,
• an outlet hole communicating a downstream side of the flow path with the back pressure chamber,
• a pilot valve body for opening and closing an end of the outlet hole on a side of the back pressure chamber,
• an elongated member holding the pilot valve body and capable of causing the pilot valve body to move in an axial direction of the elongated member,
• a rotatable member, and
• a lifter rotatable by a rotation of the rotatable member and also movable in the axial direction of the elongated member by the rotation of the rotatable member;
• wherein
• the lifter and the elongated member are connected in such a manner that the lifter and the elongated member are integrally movable in the axial direction of the elongated member, and
• the elongated member is connected to the lifter under a condition in which the elongated member is biased to the lifter in a one-way direction of the axial direction by a biasing-connecting member.