Patent ID: 11879470
Assignee: MICROMASS UK LIMITED
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC F  H | IPC F  H

Claim 0:
1. A mass spectrometer comprising:
a vacuum housing comprising a first vacuum chamber having a first gas exhaust port;
a gas pump having a first gas inlet port connected to the first gas exhaust port by a first gas conduit for evacuating the first vacuum chamber; and
a first apertured cover arranged over the first gas exhaust port or first gas inlet port, or in the first gas conduit therebetween;
wherein the first apertured cover is electrically conductive so as to prevent electric fields passing therethrough and entering the first gas inlet port and/or first gas exhaust port, through the first gas conduit; and
wherein the first apertured cover comprises a main body portion having apertures through which said gas passes and a plurality of protrusions extending away from the main body portion to respective free ends that are arranged in contact with a housing of the gas pump and/or the vacuum housing.