Abstract: A variable size is provided for a discharge port in a scroll compressor. The variable size is movable dependent on conditions within the scroll compressor to achieve a desired pressure ratio based upon operational conditions in the compressor or an associated refrigerant cycle. In one embodiment a plunger moves axially to increase or decrease the size of a discharge port. In a second embodiment, the plunger rotates about an axis and has a groove that is selectively aligned with the port to increase or decrease the effective size of the port.

Abstract: An oil spout is drilled in the crankcase of a scroll compressor between the outer seal and the coupling. The oil spout intersects the oil return chamber to redirect a portion of the oil exiting the oil return passage to the lower surface of the orbiting scroll between the outer seal and the coupling. It is preferred that the oil spout be substantially perpendicular to and smaller in diameter than the oil return passage. The oil spout provides a continual flow of additional lubrication to the outer seal and the coupling, preventing excessive wear of the outer seal and improving overall seal reliability.

Abstract: A scroll compressor has a non-orbiting scroll axially secured within an end cap. The compressor is of the sort wherein the back pressure chamber is defined behind the orbiting scroll. In one embodiment a spring biases the non-orbiting scroll toward the orbiting scroll. In other embodiments the non-orbiting scroll is force fit within the end cap.

Abstract: A scroll compressor has a non-orbiting scroll axially secured within an end cap. The compressor is of the sort wherein the back pressure chamber is defined behind the orbiting scroll. In one embodiment a spring biases the non-orbiting scroll toward the orbiting scroll. In other embodiments the non-orbiting scroll is force fit within the end cap.

Abstract: An improved bearing for a sealed compressor incorporates a bearing mount mounted radially outwardly of the bearing. Oil supply passages extend through the bearing mount to supply lubricant to the bearing. A magnet is positioned outwardly of the bearing mount, and will collect magnetic debris within the lubricant. The positioning of the magnet adjacent to the oil supply passages provides adequate removal of the debris in an efficient way.

Abstract: A sealed compressor includes a lower end cap with a u-shaped hump extending around its periphery. A weld reinforcement which is preferably a ring is welded between inner and outer legs of the u-shaped hump. The weld reinforcement ring bears a good deal of stress from internal pressures, and results in a more long-lasting housing.

Abstract: A scroll compressor is provided with a motor protector for stopping operation of its motor should conditions be indicative of a problem. The motor protector is sensitive to elevated temperature, and stops operation of the motor should a sensed temperature exceed a predetermined maximum. The motor protector is positioned in a chamber in a rear face of a base of the non-orbiting scroll. A port extends through the base of the non-orbiting scroll to connect a motor protector chamber to a suction chamber. Electric wires connect the motor protector to the motor and extend through this same port. In some embodiments, a pressure relief valve also communicates with the motor protector chamber. In one embodiment the motor protector chamber is enclosed by a cap and the pressure relief valve is mounted in that cap. In another embodiment the pressure relief valve extends through a wall of the non-orbiting scroll. In other embodiments, a pair of mating plugs connect the protector to the motor.

Abstract: A sealed compressor includes a lower end cap with a u-shaped hump extending around its periphery. A weld reinforcement which is preferably a ring is welded between inner and outer legs of the u-shaped hump. The weld reinforcement ring bears a good deal of stress from internal pressures, and results in a more long-lasting housing.

Abstract: Motor protectors are positioned in a location in a scroll compressor where they are cooled by suction refrigerant flow. If the volume of refrigerant flow decreases, then the cooling effect also decreases. In this way, the protector becomes more sensitive to the mass flow of refrigerant. Thus, the motor protector is more likely to trip in a loss of charge situation.

Abstract: An improved Oldham coupling ring is relatively easy to manufacture. Opposed circular arc portions are connected by angled portions to opposed flat portions. The circular arc portions are centered on a common center. As such, the invention is relatively easy to manufacture when compared to prior art systems.

Abstract: An improved Oldham coupling ring is relatively easy to manufacture. Opposed circular arc portions are connected by angled portions to opposed flat portions. The circular arc portions are centered on a common center. As such, the invention is relatively easy to manufacture when compared to prior art systems.

Abstract: An improved slider block for a scroll compressor has a bore including two spaced circular portions centered on a common axis. A recess is formed into one of the curved portions to provide additional clearance for movement of an eccentric pin. The recess allows the eccentric pin to move within the bore, as the relative position of the slider block and the eccentric pin move and change during operation of the scroll compressor.

Abstract: A scroll compressor includes an oil supply cross-hole extending radially outwardly to the outer peripheral surface of the base of the orbiting scroll. The cross-hole supplies lubricant against the crankcase towers such that lubricant is supplied to both the Oldham coupling and the seals for the back pressure chamber. The cross-hole is preferably positioned to be between 80° and 90° downstream from the beginning of the orbiting scroll wrap. In this position, adequate oil will be supplied to lubricate the Oldham coupling and the seal, while at the same time, it is unlikely that an undue amount of lubricant will be allowed into the scroll compressor chambers.

Abstract: A scroll compressor is provided with economizer injection ports which extend through the wrap of one of the scroll members. Preferably the injection ports are formed through a so-called “hybrid” wrap which has a varying thickness. The other scroll member is provided with grooves in its base plate. The injection of economizer fluid occurs only during a portion of the orbiting cycle when the injection port and corresponding grooves are aligned with each other. However, as the orbiting cycle continues, the injection port will no longer be aligned with the groove. At that point, the injection is ceased. This allows a simple and precise way for valving the flow of the economizer fluid into the compression chambers.

Abstract: A system includes a motor mounted within a housing and a compressor pump unit. A single-phase PSC motor includes a switch assembly which selectively connects primary or alternate windings. During normal load operation, when maximum efficiency is desired, the switch is placed in one position, then during high load operation, when maximum torque output is needed at maximum a load point, the switch is placed in the closed position. In effect, the number of main winding turns is decreased and the motor is strengthened. As the auxiliary capacitors are also now connected in parallel, the net effect is an increase in the total auxiliary capacitance, which also serves to strengthen the motor. Another embodiment provides a switch for a three-phase WYE connected motor. In yet another embodiment, a three phase delta connected motor switch is provided.

Abstract: An improved slider block for a scroll compressor has a bore including two spaced circular portions centered on a common axis. A recess is formed into one of the curved portions to provide additional clearance for movement of an eccentric pin. The recess allows the eccentric pin to move within the bore, as the relative position of the slider block and the eccentric pin move and change during operation of the scroll compressor.

Abstract: An improved heat shield for a scroll compressor is provided with a non-cylindrical end portion caught between the end cap and the non-orbiting scroll. In several embodiments, the portion provides a seal between the discharge chamber and a suction chamber. In one embodiment the portion of the heat shield is serpentine. In another embodiment the portion of the heat shield is generally u-shaped. In further embodiments the portion includes a plurality of circumferentially spaced clips. Several other embodiments are also disclosed.

Abstract: An improved bearing for a sealed compressor incorporates a bearing mount mounted radially outwardly of the bearing. Oil supply passages extend through the bearing mount to supply lubricant to the bearing. A magnet is positioned outwardly of the bearing mount, and will collect magnetic debris within the lubricant. The positioning of the magnet adjacent to the oil supply passages provides adequate removal of the debris in an efficient way.

Abstract: A scroll compressor includes an oil supply cross-hole extending radially outwardly to the outer peripheral surface of the base of the orbiting scroll. The cross-hole supplies lubricant against the crankcase towers such that lubricant is supplied to both the Oldham coupling and the seals for the back pressure chamber. The cross-hole is preferably positioned to be between 80° and 90° downstream from the beginning of the orbiting scroll wrap. In this position, adequate oil will be supplied to lubricate the Oldham coupling and the seal, while at the same time, it is unlikely that an undue amount of lubricant will be allowed into the scroll compressor chambers.

Abstract: An unloader valve for a scroll compressor to selectively communicate suction and discharge is positioned outwardly of the compressor housing. In this way, the unloader valve is ideally positioned to address several system failures. As an example, loss or charge, reverse running, fan failure, etc. are all addressed in an efficient and quick manner. The unloader valve may be the normal unloader valve controlled by a system control which also selectively controls capacity. The unloader valve control is modified such that it is also operable to open the unloader valve when a system failure is detected.