Heavy-load horizontal multi-joint robot

The invention belongs to the field of heavy-load carrying robots, and particularly relates to a heavy-load horizontal multi-joint robot which comprises a base, a large arm, an auxiliary arm and a small arm, the interior of the large arm is of a hollow structure, an I-axis rotation mechanism is arranged at the end, close to the base, in an inner cavity of the large arm, and an II-axis rotation mechanism is arranged at the other end, away from the base, in the inner cavity of the large arm. The I-shaft slewing mechanism is connected with the base, so that the large arm has the degree of freedom of rotation relative to the base, the II-shaft slewing mechanism is connected with one end of the auxiliary arm, so that the auxiliary arm has the degree of freedom of rotation relative to the large arm, and the other end of the auxiliary arm is connected with one end of the small arm; and the height position of the big arm is the same as that of the small arm. A large arm and small arm stacking series arrangement form o