Hydraulic oscillator based on cam and impeller

The invention discloses a hydraulic oscillator with a drag reduction and speed increase function which is used in the fields such as oil drilling. According to the technical scheme, an upper joint, anouter shell and a lower joint are connected in sequence through screw threads, a throttle valve plate is connected with the upper joint through screw threads and connected with cylinder pins throughlocking bolts, and the cylinder pins are located between an impeller and the throttle valve plate; an impeller shaft, an impeller and an impeller outer shell are welded into a whole, a tandem bearingis installed between the impeller outer shell and the outer shell, the upper and lower ends of the tandem bearing are positioned through an inner sleeve and an outer sleeve, and the impeller shell isnext to a cam; and circumferential positioning of the cam and the outer shell is realized through a spline, the lower end of the cam is next to the lower joint, and axial positioning is realized. According to the novel hydraulic