Variable vacuum device related to vacuum furnace and vacuumizing method

The variable vacuum device comprises a vacuum furnace body and a diffusion pump, a vacuum pipeline used for communicating the interior of the vacuum furnace body with the diffusion pump is arranged between the vacuum furnace body and the diffusion pump, a baffle is arranged in the vacuum pipeline, and the baffle is connected with an adjusting assembly used for adjusting the angle of the baffle; a detection opening communicated with the inner wall of the vacuum pipeline is formed in the outer wall of the vacuum pipeline, a vacuum detection piece is placed in the detection opening, the diffusion pump is further connected with a control center, and the vacuum detection piece and the adjusting assembly are both electrically connected with the control center. When vacuum treatment is carried out in the vacuum furnace body, the diffusion pump is opened, the vacuum detection piece measures the vacuum degree in the vacuum furnace body in real time and transmits data to the control center, and the control center adjus