Oil injection pump plunger spring capable of improving fatigue strength

The utility model provides an oil injection pump plunger spring capable of improving fatigue strength. The oil injection pump plunger spring capable of improving the fatigue strength are used for solving the problem that the oil injection pump plunger spring is prone to fatigue break in an early stage caused by sympathetic vibration. According to the technical scheme, the oil injection pump plunger spring is a compression spring with an equal diameter and an equal wire diameters, and d plus delta equals a pitch p. The oil injection pump plunger spring capable of improving fatigue strength are characterized in that an interval delta between the oil injection pump plunger spring is a variable quantity, and the value of the delta is on gradual increase from two ends to the center in a symmetrical mode. According to the oil injection pump plunger spring capable of improving fatigue strength, a variable pitch structure is adopted, namely the pitches of the spring are on gradual increase from the two ends to the ce