Scroll compressor having eccentric shaft lubrication

摘要

An eccentric shaft 5 is radially slidably inserted in a bore 6a of a bushing 6, which is inserted in an opening 8c-1 of a boss portion 8c of a movable scroll member 8 by way of a radial needle bearing 7. An axial space 24 is confined between a rear end of a bushing 6 and a bottom surface of the opening 8c-1. The space 24 is in communication with the radial bearing 7 via an annular gap 26 between faced surfaces of bushing 6 and the opening 8c-1. A radial space 23 is confined between the inner surface of the bore 6a and the eccentric shaft 5, so that a limited radial movement of the eccentric shaft 5 with respect to the bushing 6 is allowed. A washer 21 for obtaining a fixed axial location of the bushing 6 on the eccentric shaft 5 is formed with recess 21b (first passageway 25) for communicating the radial space 23 with the axial space 24. The bushing 6 is further formed with a radial hole 27 (second passageway) for communicating the radial space 23 with a crank chamber R. A recirculation passageway for the lubricant is thus generated between the crank chamber R, the gaps in the needle bearing 7, the gap 26, the axial chamber 24, the first passageway 25, the radial space 23, the second passageway 27 and the crank chamber R.