Automatic pressure relief universal grease gun

The utility model relates to the field of engineering machinery lubricating devices, and discloses an automatic pressure relief universal grease gun which comprises an automatic pressure relief module, the automatic pressure relief module is fixedly connected with a flat gun head high-pressure oil pipe and a high-pressure oil inlet pipe, the automatic pressure relief module comprises a valve element and a pressure relief oil outlet pipe, the automatic pressure relief module is rotationally connected with a trigger, and the trigger is connected with the valve element. The valve element rotates in the pressure relief module through the trigger, and an inlet of the flat gun head high-pressure oil pipe, an outlet of the high-pressure oil inlet pipe and an inlet of the pressure relief oil outlet pipe are tightly attached to the valve element. The valve element comprises a first channel and a second channel. The trigger is connected with a reset spring. An inlet of the high-pressure oil inlet pipe is connected with