Bag opening and sealing device

The opening and sealing device of the packaging bag includes a screw cap 1, a circular cutter 2, a sealing ring 3, a through-hole 4, a tight ring 5, and an annular surface on one side of the sealing ring 5 affixed to the annular surface of the ring 4-3. In the above, the sealing ring 3 is sleeved on the outside of the external thread section 4-1 and close to the ring surface 4-2. The circular cutting blade 2 is inserted into the through hole 4 and the ring 2-2 is inserted inside the screw cap 1. The inner bottom surface of the screw cap 1 is fixedly connected with the screw cap 1 and the external thread segment 4-1. The round end surface of the screw cap 1 presses the sealing ring 3, and the utility model can be used