A vacuum adsorber includes a housing having an accommodating cavity and an opening communicating with the accommodating cavity; an integrated
vacuum pump arranged inside the accommodating cavity; a control panel arranged inside the accommodating cavity and controllably connected with the integrated
vacuum pump; wherein the control panel is controllably connected with a photoelectric switch; a power-up
assembly having a guide piece and a shading movement portion; and an activating piece covering inside the opening of the housing. By means of setting the activating piece to push the shading movement portion to move in the movement cavity, when the shading movement portion moves to block beams, it causes the state of beams to change, and then
voltage inside the photoelectric switch changes; when the control panel detects a change in
voltage, it controls the pump to start operating; thereby improving the stability and reliability during starting the pump.