Piston-type engine oil pressure-limiting valve device

The invention discloses a piston-type engine oil pressure-limiting valve device, which relates to the technical field of the engines. The piston-type engine oil pressure-limiting valve device comprises an engine oil pump installed together with the an engine, wherein an installation space is formed on the pump shell of the engine oil pump; a plug screw plug is in screw joint to the upper part of the installation space; one end of a pressure-limiting spring is pressed on the screw plug; the other end of the pressure-limiting spring is pressed on the valve plug of a pressure-limiting valve; the valve plug of the pressure-limiting valve consists of a pressure bearing part and a cap part; the pressure bearing part extends into the high-pressure chamber of the engine oil pump on the oil outlet of the engine oil pump; one end of an oil drainage channel is communicated and connected with the installation space; and the other end of the oil drainage channel is communicated and connected with a storage machine oil tank of the engine oil pump. The piston-type engine oil pressure-limiting valve device is free from leaking oil in advance, the phenomena of low engine oil pressure of the engine and dry grinding on the surface of a friction pair can be avoided, and the engine reliability is good.