A pump, particularly a vane pump or roller cell pump, whereby the vane
pump or roller cell pump is provided with a two-stroke contour ring, with
a rotor, inside of which vanes or rollers are mounted in a manner that
enables them to be radially displaced, with at least one side side plate,
which seals the rotating group, with a casing and with a casing cover,
whereby the rotor is driven by a shaft and the shaft is mounted inside
the casing and, optionally, inside the cover.