Proximity switch mounting structure for small rail car and small rail car system comprising proximity switch mounting structure

The utility model provides a proximity switch mounting structure for a small rail car, which comprises a rail batten provided with a mounting section, the upper part of the mounting section is chiseled to form a mounting groove and a mounting plate positioned below the mounting groove, the mounting groove and the mounting plate are respectively in a trapezoid shape taking the two side edges of the rail batten as the bottom edges, and the short bottom edge of the trapezoid of the mounting plate is provided with an accommodating notch; the clamping plate structure is in a U shape formed by an upper clamping plate, a connecting plate and a lower clamping plate, the upper clamping plate is in a trapezoid shape matched with the mounting groove, and an inserting hole corresponding to the containing notch is formed in the upper clamping plate; the upper end of the connecting plate is connected with the trapezoidal short bottom edge of the upper clamping plate; the proximity switch is cylindrical, the radial size of