Three-gauge mixed gauge rail-changing device

The utility model discloses a three-gauge mixed gauge rail-changing device comprising two standard-gauge stock rails, a 1065 narrow gauge, a 1000 narrow gauge, an A switch rail, a B switch rail, a C switch rail, a D switch rail, two connecting rails and two guardrails; the two standard-gauge stock rails run through the rail-changing device; the 1065 narrow gauge, the 1000 narrow gauge, the A switch rail and the B switch rail are arranged at the front portion of the rail-changing device, on the inner sides of the two standard-gauge stock rails; the C switch rail, the D switch rail, the two connecting rails and the two guardrails are arranged at the rear portion of the rail-changing device, on the inner sides of the two standard-gauge stock rails; the 1065 narrow gauge and the 1000 narrow gauge comprise a straight line segment and a folding line segment; heels of the C switch rail and the D switch rail are movably connected with a large base plate of a frog heel at the middle of the rail-changing device, and the heels are connected with tail ends of the 1065 narrow gauge and the 1000 narrow gauge respectively in a contacting mode; the two connecting rails comprise straight line segments and folding line segments.