Abstract: A multiple stage cryogenic vacuum pump is disclosed for transferring matter or species between a gas and a vacuum chamber. The vacuum chamber has an orifice through which the matter or species moves and through which some of the gas leaks into the chamber. The chamber also has an interior surface which is spaced from the path of movement of the matter or species and encircles such path, and an internal divider extending to a position adjacent the interior surface and dividing the chamber into a first region adjacent the orifice and a second region downstream from the first region, with the interior surface extending in both regions. The surface is cooled by a single refrigerating device to below the condensation temperature of the gas, to produce a pressure below atmospheric in the first region and a lower pressure in the second region. The divider contains an aperture through which the matter or species travels and may itself be cooled to precool gas contacting it.

Abstract: Apparatus for analyzing trace components contained in a sample gas. The sample gas is directed into a reaction chamber and ionized. The resultant trace ions are drifted by an electric field, out of the sample gas, through an inert gas curtain and then through an orifice into a vacuum chamber where they are focused and analyzed. The curtain gas flow may be greater than the flow through the orifice, in which case the gas curtain acts as an ion window which is transparent to ions but blocks sample gas flow into the vacuum chamber. Alternatively, the curtain gas flow may be controlled to admit a desired flow of sample gas through the curtain into the vacuum chamber, in which case the gas curtain acts as a window for ions and as an infinitely variable orifice for the sample gas. Preferably the curtain gas is cryopumpable and is cryopumped by cooling the interior surface of the vaccum chamber.

Abstract: A label applicator for applying a label to an article comprising a supporting structure, a manifold defining an air chamber mounted on the supporting structure, and a plurality of conduits communicating with the air chamber. Some of the conduits are blocked off and other of the conduits are capable of transmitting a blast of air from the air chamber toward the label to remove the label and apply it to an article.

Abstract: A labelling system for labelling articles comprising a cassette label applicator having a supply of labels and a conveyor for moving articles past the label applicator where the label applicator applies the label to the articles as they are moved past the label applicator and the conveyor is adapted so the cassette label applicator may be replaced with another cassette label applicator after the supply of labels of the original cassette label applicator becomes at least substantially exhausted.