Patent ID: 6213742
Filing Date: 2001-04-10
Classification: F04C

Abstract:
A scroll-type fluid mover comprising:a fixed scroll, which includes a base plate and a volute portion extending from the base plate;a movable scroll, which includes a base plate having a first surface from which a volute portion extends and a second surface opposite to the first surface, the movable scroll includes a first boss projecting from the first surface and a second boss projecting from the second surface, wherein the two volute portions cooperate to form a variable displacement fluid pocket between the two scrolls;a drive shaft, which is driven to rotate about its axis;a eccentric shaft connected to the drive shaft, the axis of the eccentric shaft being offset from the axis of the drive shaft, wherein the eccentric shaft has a proximal end and a distal end, the proximity end being fixed to the drive shaft and the distal end being radially unsupported, and wherein the eccentric shaft supports the movable scroll at a plurality of axially spaced-apart supports locations, the first and second bosses surround the eccentric shaft, and the eccentric shaft rotatably supports the movable scroll through the first and second bosses;a first bearing located between the eccentric shaft and the first boss;a second bearing, axially spaced apart from the first bearing, located between the eccentric shaft and the second boss, wherein the first and second bearings are located at the axially spaced-apart support locations; anda rotation control mechanism engaged with the movable scroll for allowing the movable scroll to orbit the axis of the drive shaft without rotating about its own axis when the drive shaft rotates, and wherein gas is introduced into and compressed in the fluid pocket in accordance with the orbital movement of the movable scroll, and further wherein the volute portion of the movable scroll has an end surface facing the base plate of the fixed scroll, the eccentric shaft, the first boss, and the first bearing respectively extending axially at least as far as the end surface of the volute portion, whereby the eccentric shaft supports the movable scroll to prevent inclination of the movable scroll with respect to the fixed scroll.