Vacuum cap screwing mechanism of cap screwing machine

The utility model discloses a vacuum cap screwing mechanism of a cap screwing machine, and belongs to the technical field of cap screwing of cap screwing machines. A surrounding plate is fixedly connected to the top of the base, a cover cylinder is connected to the inner side wall of the surrounding plate in an inserted mode, a mounting block is fixedly connected to the inner wall of the cover cylinder, a sliding way is formed in the mounting block, a sliding rod is slidably connected to the inner wall of the sliding way, a spring is arranged on the inner wall of the sliding way, and a threaded hole communicating with the sliding way is formed in the top of the cover cylinder. A threaded rod is in threaded connection with the interior of the threaded hole, one end of the threaded rod is fixedly connected with a screwing block, one end of the sliding rod penetrates out of the installation block and is fixedly connected with a motor, and the rotating shaft end of the motor is fixedly connected with a pressing p