Positive and negative air-pressure combined seed-sowing mechanism air-chamber

The invention discloses an air chamber for a positive-negative pressure combined seeding mechanism, and relates to a seeding mechanism for a seeding machine in agricultural machinery. The air chamber comprises a seeding shaft (100), a shell (200) and a seeding plate (300); the middle of the shell (200) is provided with the seeding shaft (100); the seeding plate (300) covers the shell (200) and is connected with the seeding shaft (100); the seeding shaft (100) is a round driving shaft; the shell (200) is a round cast with negative pressure seed absorbing function and positive pressure seed feeding function; and the seeding plate (300) is a round plate provided with circular seed absorbing holes. The air chamber adopts negative pressure seed absorption and positive pressure seed feeding to reduce the seed damage rate to zero, has the advantages of saving seeds, simplifying the process of final singling and thinning, and reducing the production cost, is suitable for directly sowing seeds with small grain diamete