Graphite furnace adopting multi-layer and multi-hole injection type shielding gas input mode

The utility model discloses a multi-layer multi-hole jet type graphite furnace adopting a protective gas input mode, which comprises a furnace body, an annular upper gas circuit module arranged at the top of the furnace body, an annular lower gas circuit module arranged at the bottom of the furnace body, an upper furnace mouth quartz cover arranged at the top of the annular upper gas circuit module, and an upper furnace mouth quartz cover arranged at the bottom of the furnace body. An annular upper air sealing cavity and an annular main air inlet cavity are formed in the annular upper air path module, a plurality of first horizontal air outlet holes are formed between the annular upper air sealing cavity and the inner wall of the annular upper air path module, and a plurality of inclined air outlet holes are formed between the annular main air inlet cavity and the inner wall of the annular upper air path module. And an annular lower air sealing cavity is formed in the annular lower air path module, and a plur