Apparatus and method for alignment of the bearing of the crankshaft of a scroll compressor and a scroll compressor and device for carrying out this method

A method for mounting and aligning upper and lower bearings for supporting a crankshaft of a scroll compressor, using a single stand, the method comprising the steps of:

• providing a single bearing mounting and alignment fixture having measuring apparatus associated therewith for determining bearing play,
• providing a compressor assembly formed by mounting a body forming part of the compressor and compression elements in a casing forming part of the compressor, with a body or fixed scroll bearing on one end of a shroud defined by the casing, and then welding a cap to the shroud, the crankshaft being previously or subsequently engaged in a movable scroll bearing forming part of a movable portion of a compression stage in the compressor and into the upper bearing coupled to the body, the crankshaft having to be mounted in a lower bearing, itself mounted in a support to be fastened to the casing of the compressor,
• mounting the compressor assembly in the single bearing mounting and alignment fixture,
• displacing a free end of the crankshaft in a plurality of directions approximately perpendicular to an axis defined by the crankshaft to account for play in the upper bearing mounted in the body,
• using the measuring apparatus to determine the play in the upper bearing and then determining the axis of the lower bearing from the different displacements of the crankshaft,
• positioning the lower bearing as a function of the axis of the lower bearing, and
• fastening the support equipped with the lower bearing to the casing of the compressor.