Angular synchronization of stationary and orbiting plate scroll blades in a scroll pump using a metallic bellows

A method of assembling parts of a pump head of a scroll pump, the method comprising:

• placing a first end of a metallic bellows against a back side of an orbiting plate scroll having an orbiting scroll blade at its front side;
• placing a second end of the metallic bellows against a frame;
• mounting a fixture, having a reference feature, to an assemblage comprising the metallic bellows and the orbiting plate scroll;
• performing an angular alignment process, comprising rotating the metallic bellows, with the fixture mounted to the assemblage, until the reference feature of the fixture aligns in the circumferential direction of the metallic bellows with another reference feature provided on one of the orbiting plate scroll and the frame;
• fixing the metallic bellows, at the first end thereof, to the orbiting plate scroll;
• removing the fixture from the assemblage after the angular alignment process has been performed;
• fixing the metallic bellows, at the second end thereof, to the frame;
• and
• subsequently fixing a stationary plate scroll, having a stationary scroll blade, to the frame in a predetermined angular alignment with the frame and such that the stationary scroll blade faces the orbiting scroll blade in a radial direction,
• wherein the fixing of the metallic bellows to the orbiting plate scroll and to the frame at the first end and the second end of the metallic bellows, respectively, and the fastening of the stationary plate scroll to the frame angularly synchronizes the stationary scroll blade and the orbiting scroll blade with one another.