Angular Synchronization of Stationary and Orbiting Plate Scroll Blades in a Scroll Pump Using a Metallic Bellows

Patent metadata

Field	Value
Publication number	US-2016201670-A1
Application number	US-201615075123-A
Country	US
Kind code	A1
Filing date	Mar 19, 2016
Priority date	Apr 5, 2013
Publication date	Jul 14, 2016
Grant date	—

Abstract

Parts of a pump head of a scroll pump facilitate an assembly process in which the stationary and orbiting scroll blades of the pump are angularly aligned or synchronized with one another. A metallic bellows of the pump head provides a primary means of synchronizing the stationary and orbiting scroll blades. The assembly process may be carried out using a fixture configured to be mountable to an assemblage including the bellows and the orbiting plate scroll. The fixture has a reference feature, and the orbiting plate scroll or the frame has another reference feature that can be aligned with the reference feature of the fixture, in the circumferential direction of the bellows, during the course of the assembly process.

First claim

What is claimed is:

1 . 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 surface of a plate of an orbiting plate scroll having an orbiting scroll blade protruding from a front surface of the plate, and fixing the metallic bellows at its first end to the orbiting plate scroll, wherein the fixing of the metallic bellows to the orbiting plate scroll comprises inserting fasteners into the plate of the orbiting plate scroll from the back surface of the plate; placing a second end of the metallic bellows against an inner surface of a frame; performing an angular alignment process comprising establishing a predetermined angular alignment between the frame and the orbiting plate scroll; subsequently fixing the bellows, at a second end thereof, to the frame, wherein the fixing of the metallic bellows to the frame comprises inserting fasteners into the frame from an outer surface of the frame opposite the inner surface; 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 angular alignment process and the fastening of the stationary plate scroll to the frame angularly synchronizes the stationary and orbiting scroll blades with one another.

2 . The method of claim 1 , further comprising:
mounting bearings to the orbiting plate scroll with an end nut interposed between the bearings and the plate of the orbiting plate scroll; mounting bearings to the frame; and after the bearings are mounted to the frame, installing a unit comprising a crank shaft and counterweight in the frame and as supported by the bearings mounted to the frame; and after the bellows is fixed, at the second end thereof to the frame, inserting a bolt through the crank shaft of the unit and into threaded engagement with the end nut, and tightening the bolt to pre-load at least one of the bearings.

3 . The method of claim 1 , wherein the fixing of the metallic bellows to the orbiting plate scroll comprises inserting fasteners into blind holes open at the back surface of the plate of the orbiting plate scroll.

4 . 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 bellows and the orbiting plate scroll; performing an angular alignment process, comprising rotating the bellows, with the fixture mounted to the assemblage, until the reference feature of the fixture aligns in the circumferential direction of the bellows with another reference feature provided on one of the orbiting plate scroll and the frame; fixing the 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 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 bellows to the orbiting plate scroll and to the frame at the first and second ends of the bellows, respectively, and the fastening of the stationary plate scroll to the frame angularly synchronizes the stationary and orbiting scroll blades with one another.

5 . The method of claim 4 , further comprising setting the orbiting plate scroll on a jig, that prevents the orbiting plate scroll from rotating about its central longitudinal axis, with the back side of the orbiting plate scroll facing up, and the reference feature of the orbiting plate scroll exposed, and
wherein said another reference feature is provided on one of the orbiting plate scroll, the first end of a metallic bellows is placed against the back side of the orbiting plate scroll while the orbiting plate scroll is set on the jig, the fixture is mounted to the assemblage by mating respective portions of the fixture and the second end of the metallic bellows with one another such that the fixture is mounted to the bellows with a predetermined angular alignment therewith, the angular alignment process comprises rotating the fixture mounted to the bellows relative the orbiting plate scroll against which the first end of the bellows has been set, while the orbiting plate scroll is set on the jig, until the reference feature of the fixture aligns, in the circumferential direction of the bellows, with the reference fixture of the orbiting plate scroll, the bellows is fixed, at the first end thereof, to the orbiting plate scroll by clamping the first end of the bellows to the orbiting plate scroll, and the bellows is fixed, at the second end thereof, to the frame after the bellows has been fixed to the orbiting plate scroll.

6 . The method of claim 5 , wherein the placing of the first end of the bellows against the back side of an orbiting plate scroll comprises inserting an annular flange of the bellows into a complementary circular recess in the back side of the orbiting plate scroll.

7 . The method of claim 6 , wherein the fixture is mounted to the assemblage by respectively inserting pins of the fixture into holes provided in the second end of the metallic bellows.

8 . The method of claim 7 , wherein the fixing of the bellows, at the second end thereof, to the frame comprises inserting fasteners through said holes provided in the second end of the metallic bellows.

9 . The method of claim 5 , wherein the fixture is mounted to the assemblage by respectively inserting pins of the fixture into holes provided in one of the ends of the metallic bellows.

10 . The method of claim 9 , wherein the fixing of the bellows, at the second end thereof, to the frame comprises inserting fasteners through said holes provided in the second end of the metallic bellows.

11 . The method of claim 4 , wherein the another reference feature is provided on the frame,
the bellows is fixed, at the first end thereof, to the orbiting plate scroll before the angular alignment process is performed, the second end of the bellows is set against the frame while the orbiting plate scroll is fixed to the bellows at the first end thereof, the fixture is mounted to the assemblage by mating respective portions of the fixture and the orbiting plate scroll with one another such that the fixture is mounted to the orbiting plate scroll with a predetermined angular alignment therewith, the angular alignment process comprises rotating an assemblage, comprising the bellows, the orbiting plate scroll fixed to the bellows, and the fixture mounted to the orbiting plate scroll, relative to the frame until the reference feature of the fixture is aligned with the reference feature provided on the frame, and the bellows is fixed, at the second end thereof, to the frame after the angular alignment process has been performed.

12 . The method of claim 11 , wherein the fixture is mounted to the assemblage by mating a portion of the fixture with a portion of the orbiting scroll blade.

13 . The method of claim 11 , wherein said mating comprises respectively inserting pins of the feature into holes in the orbiting scroll blade.

Assignees

• Agilent Technologies Inc

Inventors

• Calhoun John
• Galica George
• Lu Vannie Yucong
• Pierce James

Classifications

• F01C17/06

  using cranks, universal joints or similar elements (F01C1/07 takes precedence) · CPC title

• F04C2230/603

  Centering; Aligning · CPC title

• F04C18/0269 Primary

  Details concerning the involute wraps · CPC title

• F04C2/025

  the moving and the stationary member having co-operating elements in spiral form · CPC title

• F04C18/0215 Primary

  where only one member is moving · CPC title