Patent ID: 8745772

Claim:
A discharge valve apparatus on a rinse water tank for storing rinse water for flushing a toilet, said apparatus comprising: a valve body for opening and closing a discharge port disposed on a bottom surface of a rinse water tank; a control cylinder member for controlling flow of rinse water flowing out of the discharge port from the rinse water tank when the valve body releases the discharge port, an opening portion being formed in the control cylinder member to permit rinse water to pass through the control cylinder member; and an adjusting member attached at a changeable predetermined attachment position on the control cylinder member and the adjusting member being capable of adjusting an opening surface area of the opening portion in the control cylinder member according to the changeable predetermined attachment position; the control cylinder member and the adjusting member being respectively furnished with engaging portions by which they mutually engage, and one of the control cylinder member engaging portion and the adjusting member engaging portion being a male engaging portion, while the other of the control cylinder member engaging portion and the adjusting member engaging portion being a female engaging portion; the female engaging portion being arrayed in essentially a straight line fashion, and being furnished with a registration indentation for registering the changeable predetermined attachment position of the adjusting member relative to the control cylinder member, and a gap within said registration indentation being set to be smaller than a width of an installer's finger, so that a manipulation by an installer's finger to release the engagement between the male engaging portion and the female engaging portion is prevented when the adjusting member engaging portion is in a state of engagement with the control cylinder member engaging portion.