Prevent suck -back pendular ring vacuum apparatus

The utility model relates to a vacuum system field, aim at provides a prevent suck -back pendular ring vacuum apparatus, prevent suck -back pendular ring vacuum apparatus, including liquid ring vacuum pump, vacuum buffer tank, connecting tube, power and control switch, the one end of connecting tube links to each other with liquid ring vacuum pump's induction port, and the other end of connecting tube links to each other with the vacuum buffer tank, is equipped with the vacuum bleeder valve on the gas outlet of vacuum buffer tank, and vacuum bleeder valve and liquid ring vacuum pump are connected with the control switch electricity respectively, and control switch is connected with the power electricity. The utility model has the advantages of vacuum bleeder valve and liquid ring vacuum pump are connected to same power and adopt same control switch and power to control, and when liquid ring vacuum pump cut off the power supply, the vacuum bleeder valve loses the electricity and opens, and the gas in the buffe