A drain valve assembly contains a body including a chamber, at least one rotatable stop portion, a first receiving orifice, a discharge orifice, a coupling orifice, and a second receiving orifice. A shaftless ball valve is received in the chamber and includes a fixing orifice, an opening, a first draining orifice, a second draining orifice, a third draining orifice and a stopping face. A first reinforcement ring is mounted on the upper support portion and the lower support portion. A second reinforcement ring is located at an upper portion of the chamber. A positioning ring includes a through orifice and an abutting portion. A controller includes a connection portion and an operation portion. A limiter is configured to connect the controller with the coupling orifice, and a filtration holder disposed on the first receiving orifice.

A connection structure of a ball valve of a control valve for draining water out of a water sink contains: a body, a filtration cap, the ball valve, a handle bar, and a positioning ring. The body includes a first connecting portion configured to connect with the filtration cap, a second connecting portion configured to accommodate the ball valve, a coupling portion, and a fixing portion. The filtration cap includes multiple filtering orifices configured to guide wasted water into the body. The ball valve is spherical and is received in the second connecting portion, and the includes a guide orifice passing and a connection portion. The handle bar is inserted into the coupling portion and connected with the connection portion so that the handle bar is engaged by the handle bar to be turned on/off. The positioning ring is received in the fixing portion.

A connection structure of a ball valve of a control valve for draining water out of a water sink contains: a body, a filtration cap, the ball valve, a handle bar, and a positioning ring. The body includes a first connecting portion configured to connect with the filtration cap, a second connecting portion configured to accommodate the ball valve, a coupling portion, and a fixing portion. The filtration cap includes multiple filtering orifices configured to guide wasted water into the body. The ball valve is spherical and is received in the second connecting portion, and the includes a guide orifice passing and a connection portion. The handle bar is inserted into the coupling portion and connected with the connection portion so that the handle bar is engaged by the handle bar to be turned on/off. The positioning ring is received in the fixing portion.

A drain valve comprises a valve shell and a valve core which comprises an inner core and an outer core. In the process of draining and closing, the outer core and the inner core of the valve is rotated through operating the handle nut and a rotating part, so as to realize the accurate control of the position of the valve core. When draining water, the first through hole and the second through hole are aligned, and then water is drained to the water outlet pipe through the outlet of the valve core, so that the drainage is smooth; when closed, the valve core is completely pushed into the interior, and the internal water is squeezed out, thus reducing the possibility of residual water, effectively preventing the drain valve from being frozen, and ensuring the normal use of the drain valve in cold climates.