Micro high-pressure plunger sleeve

The micro high-pressure plunger sleeve comprises a sleeve body, a valve element and a plunger, an oil supply channel and an oil supply cavity are formed in the sleeve body, an oil supply hole is formed in the sleeve body, the oil supply hole is suitable for enabling oil to enter the oil supply channel, the valve element is arranged in the oil supply cavity, and the valve element is suitable for preventing the oil in the oil supply channel from entering the oil supply cavity; the plunger does circulating reciprocating motion in the oil supply channel, the plunger is suitable for enabling oil in the oil supply channel to eject the valve element open to enter the oil supply cavity, an ejector is arranged on the plunger, the ejector is embedded in the plunger in a sliding mode, the ejector is suitable for ejecting the valve element open, the sleeve can supply oil through the pressurization action of the plunger, and when the valve element is blocked, the valve element can be inserted into the oil supply cavity. T