Bridge expansion joint external iron sheet rain gutter device

The utility model discloses a bridge expansion joint external iron sheet rainwater tank device which comprises a first bridge, a connecting block, a dirt collecting plate, a second bridge and a watercollecting tank, the connecting block is clamped and fixed between the first bridge and the second bridge, a groove is formed in the top of the connecting block, and second water leaking holes are formed in the front side and the rear side of the groove. A sewage collecting plate is placed in the groove, first water leaking holes are formed in the front side and the rear side of the sewage collecting plate, pull rings are rotationally connected to the positions, on one sides of the first water leaking holes, of the sewage collecting plate, a water collecting groove is fixed to the top of the connecting block, and water inlet holes are formed in the two sides of the top of the water collecting groove. Drain holes are formed in two sides of the bottom of the water collecting tank. Through the arrangement of the conn