Abstract: A refrigerant motor/compressor employs both a serviceable shaft-grounding device and a ceramic coating to protect a rolling element bearing that could otherwise be damaged by high frequency induced common mode voltage and current originating from an inverter that includes a plurality of IGBTs (insulate gate bipolar transistors). The shaft-grounding device includes a stranded copper wire brush that rides against an axial end of the shaft and a high frequency stranded grounding wire that conducts the induced current away from the shaft. The shaft-grounding device is sized and positioned so that it can be momentarily removed for inspection without having to evacuate the refrigerant. The ceramic coating provides an electrical insulating surface on a bearing bracket and other parts that support the bearing. The coating comprises titanium dioxide and aluminum oxide to provide a surface that is sufficiently hard and tough to resist damage during assembly, thereby maintaining the coating's integrity.

Abstract: The flow, use, interaction and separation of lubricant and gas flowing through the suction pressure portion of a low-side refrigeration scroll compressor is managed by the use of a drive motor mounting sleeve and a multi-ported frame. The mounting sleeve and frame provide for the direction of oil to surfaces within the low side of the compressor shell which require lubrication as well as the conduct of suction gas to the scroll compression mechanism in a manner which cools the compressor drive motor yet which maintains the respective flows of oil and suction gas sufficiently separate to ensure that excessive amounts of oil are not conducted out of the compressor in the gas which is compressed thereby. Lubrication is enhanced by the use of a vent passage which opens into a relatively lower pressure region within the suction pressure portion of the compressor shell.

Abstract: A scroll-type refrigeration compressor has a gas-liquid mixture discharge passage extending through the driver scroll drive shaft for discharging refrigerant gas and entrained lubricant into a high pressure chamber in the compressor housing. An anti-reverse rotation valve is connected to the distal end of the drive shaft and includes a valve housing with radially extending discharge ports and a closure member movable to prevent reverse flow of high pressure gas to the scroll compression chambers to prevent reverse rotation on compressor shutdown. A pressure equalization port may be formed in the valve closure member, valve housing or the distal end of the drive shaft to allow slow bleed down of pressure from the high pressure side to the low pressure side to minimize starting torque of the drive motor. The valve may be formed from a tubular metal housing and having a plug-type closure member slidably disposed therein with the housing being press fitted in a counterbore in the end of the shaft.

Abstract: The flow, use, interaction and separation of lubricant and gas flowing through the suction pressure portion of a low-side refrigeration scroll compressor is managed by the use of a drive motor mounting sleeve (46) and a multi-ported frame (40). The mounting sleeve and frame provide for the direction of oil to surfaces within the low side of the compressor shell which require lubrication as well as the conduct of suction gas to the scroll compression mechanism in a manner which cools the compressor drive motor yet which maintains the respective flows of oil and suction gas sufficiently separate to ensure that excessive amounts of oil are not conducted out of the compressor in the gas which is compressed thereby. Lubrication is enhanced by the use of a vent passage (68) which opens into a relatively lower pressure region within the suction pressure portion of the compressor shell.

Abstract: Protective apparatus in a scroll compressor, in the form of a valve assembly, is operative to prevent compressor damage from reverse direction rotation of the scroll compression mechanism or the development of abnormally high discharge gas temperatures. The valve assembly is disposed in a passage communicating between the suction and discharge pressure portions of the compressor shell and houses a discharge temperature sensor immediately adjacent the location from which discharge gas issues from the compression mechanism. The location of the sensor and its exposure to discharge gas permits the timely sensing of abnormally high discharge temperatures and the shutdown of the compressor upon their occurrence.

Abstract: In a co-rotational scroll apparatus having two interleaving scroll wraps secured to end plates rotating about parallel, non-concentric axes, a procharging device affixed to one end plate and substantially enclosing the scroll wraps and the second end plate. Preferably, the procharging device includes a cup-shaped drive housing secured to one end plate and enclosing the scroll wraps, and a flexible torque-transmitting member connecting between the enclosure member and the second end plate. Apertures are provided in the enclosure member to permit fluid flow into the space enclosed by the enclosure device, with vanes disposed adjacent the apertures to force fluid into the enclosed space during rotation of the scroll wraps. Fluid thus forced into the enclosed space is precharged prior to entering the scroll wraps, being at higher pressure than fluid exterior the enclosed space, improving the operating efficiency of the scroll apparatus.

Abstract: A low side scroll compressor is protected from both the potentially damaging effects of improper electrical hookup and the development of high discharge temperatures by apparatus disposed in a passage which communicates between the suction pressure portion and a discharge pressure portion of the compressor. The apparatus operates to permit gas flow from the suction to the discharge pressure portion of the compressor through a protective passage, such as when the compressor runs backwards due to miswiring, so as to avert damage to the scroll members. The apparatus permits the flow of gas from the discharge to the suction pressure portion of the compressor through the passage when the temperature of the discharge gas produced by the compressor exceeds a predetermined temperature indicative of an abnormal compressor operating condition. The resulting gas flow in the latter case causes the compressor motor to de-energize.

Abstract: In a co-rotational scroll apparatus having two interleaving scroll wraps secured to end plates rotating about parallel, non-concentric axes to produce a relative orbital motion, a means for enhancing lubricant flow through the scroll wraps. One or more passages are provided in one or both of the scroll end plates, each passage disposed to discharge lubricant between the scroll end plates, discharging adjacent the outer end of the scroll wraps immediately before the point where the scroll wraps form the first compression chamber to provide lubricant to the entire scroll wrap length. Lubricant is provided to the passages by a combination of pickup tubes affixed to the scroll end plates and inlet openings in the scroll end plates. The inlet openings accept lubricant discharged from the bearings in the apparatus. The pickup tubes rotate with the scroll end plates and remove lubricant from a sump adjacent the scroll end plates.

Abstract: In a co-rotational scroll apparatus having two interleaving scroll wraps secured to end plates rotating about parallel, non-concentric axes, a precharging device affixed to one end plate and substantially enclosing the scroll wraps and the second end plate. Preferably, the precharging device includes a cup-shaped drive housing secured to one end plate and enclosing the scroll wraps, and a flexible torque-transmitting member connecting between the enclosure member and the second end plate. Apertures are provided in the enclosure member to permit fluid flow into the space enclosed by the enclosure device, with vanes disposed adjacent the apertures to force fluid into the enclosed space during rotation of the scroll wraps. Fluid thus forced into the enclosed space is precharged prior to entering the scroll wraps, being at higher pressure than fluid exterior the enclosed space, improving the operating efficiency of the scroll apparatus.

Abstract: A low side scroll compressor is protected from both the potentially damaging effects of improper electrical hookup and the development of high discharge temperatures by the disposition of a valve member in a passage which communicates between the suction pressure portion and a discharge pressure portion of the compressor. The valve operates to permit the flow of gas from the suction to the discharge pressure portion of the compressor through a protective passage when the compressor is caused to run backwards due to miswiring so as to avert damage to the scroll members. The valve permits the flow of gas from the discharge to the suction pressure portion of the compressor through the protective passage when the temperature of the discharge gas produced by the compressor is caused to exceed a predetermined temperature. The resulting flow causes the compressor motor to de-energize.

Abstract: In a co-rotational scroll apparatus having two interleaving scroll wraps secured to end plates rotating concurrently about parallel, non-concentric axes to produce a relative orbital motion, a scroll member including an annular biasing chamber formed in one scroll member end plate opposite the scroll wrap and a passage from one of the chambers formed by the scroll wraps for providing fluid to the chamber. The fluid exerts a force upon a pressure plate secured to the opposing scroll end plate and thereby acts to bias the scroll wraps into contact with the opposing scroll end plate. Seals are provided in the biasing chamber of the scroll end plate to ensure contact with the pressure plate of the opposing scroll member.

Abstract: In a co-rotational scroll apparatus having two interleaving scroll wraps secured to end plates rotating about parallel, non-concentric axes to produce a relative orbital motion, a means for providing positive lubricant flow through the scroll wraps. A sump is provided adjacent the idler scroll member for supplying lubricant to a lubricant pump disposed in the lower end of the shaft of one scroll member. A lubricant gallery is provided in the scroll shaft for receiving the lubricant from the pump and directing the lubricant through passages in the scroll shaft to lubricate the scroll shaft bearing and for directing lubricant to passages in the end plate of the scroll member to be discharged adjacent the outer ends of the scroll wraps into the alternatively open and closed first chamber formed by the scroll wraps.

Abstract: In a co-rotating scroll apparatus wherein one scroll is a drive scroll and the other scroll is an idler scroll, an axial pressure balancing mechanism and means for discharge pressure balancing is disclosed. The drive scroll wrap is provided with an end plate having a plurality of extension members extending thereform. The extension members extend through corresponding slots in an Oldham coupling ring to drive the idler scroll in relative orbital rotation. The extension members further extend through clearance slots in the end plate of the idler scroll to secure a compression plate and spring biasing the end plate of the idler scroll toward the drive scroll to provide improved axial compliance between the scrolls. Means for axial pressure balancing of the idler scroll shaft and the drive scroll drive shaft are disclosed. The apparatus also includes axial thrust bearings for preventing axial oscillations of the drive and idler scrolls.

Abstract: In a compressor of the hermetic, scroll-type, a motor engaging drive shaft having a net axial thrust load determined by the pressure of compressed fluid acting upon the opposing ends of the shaft. In the preferred embodiment, the shaft includes a first end in the discharge pressure portion providing a first plan view area and a second end in the suction pressure portion having a circular, eccentrically disposed cavity with a second plan view area. The shaft has an axial bore for communicating refrigerant at discharge pressure through the shaft between the respective ends such that refrigerant at discharge pressure acts in opposite directions upon both of the respective plan view areas to balance the net thrust load of the shaft.

Abstract: Inside the hermetic shell of a scroll compressor, a normally closed solenoid valve seats against the back side of a stationary scroll plate to close a discharge opening through the plate. A coil circuit that actuates the valve has an electrical resistance that increases with temperature. The temperature dependent resistance allows the coil circuit to also function as a discharge temperature sensor. Should the discharge gas over-heat, the compressor motor and the valve are de-energized in response to the resistance exceeding a predetermined limit. The closed valve prevents backflow from rapidly reversing the rotational direction of the compressor, which can be extremely noisy and damaging to the compressor. Both the valve and the compressor motor are energized at the same time, regardless of the compressor's direction of rotation.