Abstract: An upper housing for rotatably supporting a driving scroll in a sealing container is provided with an annular chamber to be maintained at the atmospheric pressure. The annular chamber is communicated with a compression chamber formed between the driving and driven scrolls through a discharge conduit which is formed in the driving shaft of the driving scroll. The annular chamber is communicated with the inside of the container through a throttling path. An oil stored in the lower part of the container is induced with the compression chamber during the revolution of the both scrolls to be introduced into the annular chamber. Owing to the throttling path, the oil is stored in the annular chamber to separate the inside of the container and the annular chamber kept at the atmospheric pressure.

Abstract: A scroll-type apparatus having a main journal bearing which journals the drive shaft of the apparatus and is capable of pivoting by small angles with two degrees of freedom. The main journal bearing comprises three or more arcuate pads whose inner surfaces journal the drive shaft and which are pivotably supported by a stationary main bearing housing. In a preferred embodiment, each of the pads has a spherical protrusion and two rotation-preventing pins secured to its back surface. The protrusions contact the inner surface of the main bearing housing and pivotably support the pads, while the rotation-preventing pins are inserted into grooves formed on the inner surface of the main bearing housing.

Abstract: A scroll type hydraulic machine having an improved thrust bearing structure, whereby the thrust bearing is capable of tilting radially and peripherally. The thrust bearing is preferably composed of at least three sectors, and an anti-rotation member is provided between adjacent ones of the sectors. A bearing support is provided, a portion of which has the form of a ball. The thrust bearing is surrounded by an annular portion whose height is substantially the same as that of the thrust bearing.