Refueling gun

A refueling gun, comprising:

• a housing, wherein a pump body is provided within the housing, the pump body is connected to an oil intake pipe and an oil outlet pipe, and a first check valve through which oil is delivered into the pump body is provided within the oil intake pipe;
• a valve rod, wherein the valve rod penetrates into the pump body, an end portion of the valve rod located in the pump body is connected to a negative pressure generating assembly, the negative pressure generating assembly comprises a disk, a plurality of limiting members that are fixed to the same side of the disk and that are distributed circumferentially, and a sealing ring, the disk is fixedly connected to an end portion of the valve rod, the plurality of limiting members and the valve rod are distributed on two sides of an axial direction of the disk, the sealing ring is sleeved on the periphery of the plurality of limiting members, the sealing ring is capable of reciprocating along the limiting member, a sliding direction of the sealing ring is perpendicular to a surface of the disk, the sealing ring is capable of sealingly abutting against the disk after sliding in the direction toward the disk, and the sealing ring is slidingly connected to an inner wall of the pump body and is sealingly connected to the inner wall of the pump body;
• and
• a handle, wherein the handle is rotatably provided on the housing and is connected to the valve rod by means of a connecting assembly so as to drive the valve rod to reciprocate within the pump body.