Distribution box for trolley bus

The distribution box comprises a box body, the box body is installed on the lower portion of a downwards-concave structure of a trolley bus roof, an air guide plate is arranged above the downwards-concave structure, the downwards-concave structure and the air guide plate form a heat exchange space, a sealing cavity and a ventilation cavity are formed in the two sides in the box body respectively, the interior of the sealing cavity is sealed, and the ventilation cavity is arranged in the box body. A heat dissipation opening is formed in the side wall of the ventilation cavity of the box body, and a filter screen is mounted at the heat dissipation opening; an exhaust channel is vertically arranged between the filter screen and the right side wall of the electric car, an air outlet channel is arranged on the right side of the downward-concave structure, and an air outlet of the exhaust channel is connected to the middle of the air outlet channel. An upper heat exchange plate is arranged at the top of the box bod