Forming appliance for tetrahedron filtering packet

The utility model discloses a forming device for a tetrahedral filter-bag, which comprises a transversely-sealed welding and cutting device and a transversely-sealed reciprocating gyration device. The transversely-sealed reciprocating gyration device comprises a fixed platform and a stepping motor arranged on the fixed platform. The bottom of the transversely-sealed welding and cutting device is fixedly provided with a hollow rotating shaft, the transversely-sealed welding and cutting device is arranged on the fixed platform through the hollow rotating shaft in a rotary way, the transversely-sealed welding and cutting device and the stepping motor are positioned on the upper platform surface of the fixed platform, the output shafts of the hollow rotating shaft and the stepping motor extend out of the lower platform surface of the fixed platform, and the two shafts are connected with each other through a belt drive. A synchronous motor is utilized to drive the transversely-sealed welding and cutting device dir