The invention relates to a
check valve sand supply device of a sand ejector. The
check valve sand supply device comprises a sand hopper, a valve body, an upper
valve seat, a lower
valve seat, a box body, an iron box, a pneumatic switch, a first conveying air
pipe and a second conveying air
pipe, wherein a hollow valve cavity is formed in the valve body, a limiting plate is arranged in the valve cavity, the limiting plate is provided with a circular
ball valve, the upper
valve seat and the lower valve seat are respectively provided with a sand flow hole, the sand hopper is fixed on the upper valve seat, the bottom of the sand hopper is provided with a sand inlet, the box body is fixed below the lower valve seat, a sand ejection passage is formed in the box body, the first conveying air
pipe is connected and communicated with the sand ejection passage, the second conveying air pipe is connected and communicated with the bottom of the valve cavity, and the iron box is arranged below the box body. According to the
check valve sand supply device, the circular
ball valve is controlled by a pneumatic device to be switched on or off, the accurate reciprocating work state of a valve core is guaranteed, the valve core is relatively reliable to reset, the malfunction rate of the check valve is greatly reduced, the reliability of the check valve is improved, the sand leakage defect of a traditional
plugboard sand supply device can be solved, and the
operating environment can be greatly improved.