Abstract: A scroll compressor is provided with a generally spiral wrap having an abradable or conformable coating on radially inner portions of its tip. The coating is not applied to radially outer portions. During operation of the scroll compressor, the coating will eliminate tip gap leakage adjacent radially inner, higher discharge pressure portions of the compression process. The outer, non-coated portions will bear the axial load, and ensure the coating will not wear away to an undue amount.

Abstract: A self-modulating scroll compressor includes a pair of valves. A first valve moves to a low capacity position when the pressure differential is below a predetermined amount. A second valve moves to a low capacity position when the suction pressure is above a predetermined amount. Low capacity operation will only occur when both valves are open. The present invention thus provides a scroll compressor design with the ability to self-modulate and control the conditions under which low capacity operation occurs based upon two criteria.

Abstract: A scroll compressor has lubricant flow which communicates lubricant onto a motor protector when adverse conditions are present causing the motor protector to trip the motor and stop further rotation. The lubricant is returned to an oil sump through a normal return path. The normal return path outlet may be positioned above the motor protector such that lubricant will contact the motor protector when adverse conditions are present, or the outlet may be remote from the protector. When the outlet is remote from the protector, a funnel and tubing divert the oil to the motor protector under adverse conditions. Alternatively, a passage communicating with the normal return path is selectively blocked when an adverse condition is present. At that time, lubricant is forced into an alternative oil path, which is positioned above the motor protector.

Abstract: A compressor comprises a compressor pump unit and a motor for driving the pump unit. A compressor housing surrounds the compressor pump unit and the motor. A cable supplies power to the motor through a power supply housing mounted to the compressor housing. The power supply housing has a fence with a slot that permits insertion of the cable along a first axis and removal of the cable along a second axis transverse to the first axis. A clip couples the cable to the power supply housing, limiting movement of the cable along the second axis.

Abstract: Scroll compressors include a tap for communicating a compressed refrigerant to a back pressure chamber to resist a separating force. A restriction is placed within this tap to slow build-up of the back pressure chamber at start-up. Further, the restriction smoothes out any fluctuations in the back pressure force as the pressure in the compression chamber from which the refrigerant is tapped may fluctuate.

Abstract: A check valve retainer for a scroll compressor includes a retaining lip that fits into a recess formed in a scroll. The retaining lip may be manufactured as an integral part of the check valve retainer for press fitting or may be formed by an expansion fit locking member having a protrusion that forces a portion of check valve retainer wall into the recess. The retaining lip ensures that the check valve retainer stays attached to the scroll without risking scroll deformation.

Abstract: An oil pump for a scroll compressor has a bearing hub with a vent disposed between at least one fluid inlet in the bearing hub and a thrust washer. The vent provides an additional fluid flow path to equalize fluid pressure underneath the thrust washer. By minimizing or eliminating low fluid pressure zones with the bearing hub, fluid flow through the oil pump can be maintained at a constant level.

Abstract: A scroll compressor having a hybrid wrap is defined to have its wrap origin offset from a drive center of both the orbiting and non-orbiting scroll members. The offset is selected in a direction such that it eliminates extremes in the torque curve relative to shaft rotation. In this way, torque reversal is generally eliminated.

Abstract: A scroll compressor includes an adjustable actuator mount that changes the relative position of a non-orbiting scroll and an orbiting scroll to change the compressor capacity. In one embodiment, the scroll wrap and base of each scroll are manufactured as two separate components with a wrap modulator between the scroll wrap and the base of each scroll. As the mount moves the scrolls apart and together, the wrap modulators extend and retract the scroll wraps relative to their respective bases to maintain fluid-tight compression chambers.

Abstract: Several transmission embodiments selectively communicate rotary drive to an orbiting scroll to achieve capacity modulation. In these embodiments, when the motor is driven in a first direction, the orbiting scroll is driven at a rate which is equal to the motor speed. However, if the motor is driven in a reverse direction, the orbit rate of the orbiting scroll is reduced. The transmission ensures that the orbiting scroll member itself is driven in the proper forward direction regardless of whether the motor is being driven in forward or reverse.

Abstract: A scroll compressor is provided with a hybrid having thicker wrap portions and thinner wrap portions. The problem of uneven thermal expansion is addressed by providing a recess in the thicker portion. The recess communicates with the inner higher pressure and higher temperature compression chambers to communicate the higher temperature refrigerant along the face of the thicker portion. The recess blocks flow of this refrigerant to the radially outer end of the thicker portion which communicates with a lower pressure/lower temperature chamber. The use of the recess compensates for uneven thermal expansion by bringing the thicker portion to a more even temperature across its width.

Abstract: A lower shell for a sealed compressor includes a shape with a plurality of intricate bends. In particular, u-shaped sections are stamped into a plainer sheet of material to form the lower shell. This stamping process can cause brittleness in the lower shell. Thus, after the stamping process, the lower shell is subjected to a heat-treating process to reduce the brittleness. After the heat-treating process a center shell is welded to the lower shell.

Abstract: A cooling passage is formed through the wrap of a non-orbiting scroll. The cooling passage communicates with suction pressure refrigerant and passes the suction pressure refrigerant through both the base and the wrap of the non-orbiting scroll to cool an interface between suction pressure chamber and discharge pressure chambers. Preferably the cooling passage extends for a relatively great circumferential extent, and preferably more than 45°. More preferably the passage extends for more than 90°. The cooling passage provides a heat barrier increasing the efficiency of compression. Moreover, by having the suction pressure flow to the interface between the thicker portion of the wrap and the opposed base of the orbiting scroll, several benefits are obtained with regard to reliable operation of the scroll compressor.

Abstract: A simple, stamped counterweight is formed from a flat sheet of metal. The counterweight is attached to an uppermost portion of the end ring of the motor rotor. In this way, the counterweight requires little axial space, and is a very simple item to produce and assemble.

Abstract: An improved method of aligning the bearing components within a scroll compressor includes the step of mounting the crankcase to be an interference fit within the center shell, and having a surface abutting a true upper surface of the shell. This ensures that the axis of the bearing in the crankcase is idealized and centered on the center axis of the center shell. At the same time, the lower bearing is mounted on the lower end cap, and is also cut to be concentric with a force fit outer surface of the end cap. This ensures the lower bearing is also centered on the inner periphery of the center shell. Once it is ensured the center shell is true, then it is also thus ensured the upper and lower bearings are aligned on a common axis. An improved lower bearing structure with a reverse taper is also disclosed. In some embodiments, the outer surface to be machined to be concentric with the inner surface is provided by a separate part which is welded to the lower end cap.

Abstract: A scroll compressor has lubricant flow which communicates lubricant onto a motor protector causing the motor protector to trip the motor and stop further rotation when a predetermined lubricant temperature is reached. The motor protector is surrounded by a reservoir which maintains contact between the motor protector and the lubricant, thus facilitating heat transfer between the motor protector and the lubricant. The lubricant is returned to an oil sump remote from the compressor pump set when the reservoir is filled.

Abstract: A sealed compressor assembly includes a compressor pump driven by a motor mounted within a sealed housing. The sealed housing comprises a center shell extending between first and second ends and a lower shell attached to the center shell. The lower shell is generally square shaped with mounting feet extending diagonally from each corner. The lower shell includes a predetermined amount of material removed to shift the resonance frequency of the sealed housing outside the operating frequency range of the motor and compressor.

Abstract: Low voltage electrical power is supplied to a diagnostic control device in a sealed compressor. Electrical power is tapped from a high voltage power line and transformed to low voltage power that in turn operates the diagnostic control device. The diagnostic control device and the electric voltage transforming system are housed within the sealed compressor shell, thus eliminating the need for additional openings in the compressor shell. Other low voltage devices can be powered in this way.

Abstract: A scroll compressor includes a non-orbiting scroll having a plurality of radially extending ribs on its rear face. The non-orbiting scroll preferably provides a separating function separating the interior of the sealed housing of the compressor into the discharge and suction pressure chambers. The ribs extend from a central portion of the base of the non-orbiting scroll to its outer peripheral surface. A circumferentially extending rib also connects the plural radially extending ribs.

Abstract: A low cost protective clutch member is positioned adjacent an end of the drive shaft in a scroll compressor. The device is a thin washer having a tab which is selectively driven against the housing stop when the compressor is driven in a forward direction, but is movable into a notch in the shaft when the shaft is driven in a reverse direction. The tab prevents rotation of the shaft when in the notch.