Electric push rod speed regulating device for HST stepless speed change used in agricultural machinery

The invention discloses an electric push rod speed regulating device for HST stepless speed change used in agricultural machinery. The device is characterized in that an electric push rod is hinged toa crank plate of a speed regulating handle and a rocker of an HST continuously variable transmission correspondingly, and a linear displacement sensor is arranged on the electric push rod side by side and is used for measuring the displacement of the electric push rod; a U-shaped fork pulled by an electromagnet is tightly attached to a short right-angle transition groove of a parking gear, and four strain gauges form a measuring bridge at the portions, higher than a panel by 15 mm, of the front side surface and the rear side surface of the speed regulating handle, and is used for sensing whether the speed regulating handle is pushed forward or pulled backwards or not; a differential signal of the electric bridge is collected by a single-chip microcomputer after being amplified by an instrument operational amplifi