Manual packaging bag heat sealing machine stable in heating

The manual packaging bag heat sealing machine comprises a square upper plate and two heat sealing plates located on the inner circumference of the upper plate, heat conduction grooves are formed in the adjacent sides of the two upper plates, heat conduction plates are installed on the inner circumferences of the heat conduction grooves, heating grooves are formed in the opposite sides of the two heat conduction plates, and the heating grooves are communicated with the heat conduction grooves. A heating wire used for heating is arranged between the inner peripheries of the two heating grooves, a temperature sensor is installed on the top of the heat sealing plate, moving pieces used for pressing fit are arranged between the same sides of the two heat conducting plates, a balance weight plate is arranged below the upper plate, a lifting plate is arranged between the balance weight plate and the upper plate, and the balance weight plate is connected with the lifting plate. And four lifting pieces for driving the