Abstract: A frameless air handling enclosure is made possible by the use of double-flanged edges on the enclosure's side and bottom panels. The edge configuration provides reinforcement and rigidity to an otherwise flexible panel and also provides a mating surface for fastening the panels together. The enclosure includes an access opening that is covered by a removable access panel having a lining of sound and thermal insulating material. The access panel is installed by first sliding it upward into engagement with a top flange retainer and then sliding it back down into engagement with a bottom flange retainer. Upon engagement with both flange retainers, the lining of insulation is compressed against the perimeter of the access opening. This compression fit not only helps hold the access panel firmly in place but also provides a weathertight seal around the perimeter of the opening.

Abstract: A wind-driven electric current-producer has a magnetic field producing alternator rotor directly driven by an air turbine blade. The alternator and blade together are mounted on a vertically tiltable control frame which is pivotably mounted on a main frame that swivels with the wind direction in response to a guide vane. In high winds the blade and alternator tilt upward but continue to aim into the wind and produce current. The guide vane is low to accomodate the tilted blade path. The location of the pivot causes gravitational forces to tilt the control frame in both directions. Springs counterbalance the upward tilting forces. The spring mounts have a stop that limits the tilt in both directions.

Abstract: A residential heat pump installation includes a variable speed reciprocating compressor. The compressor speed control components, which include an inverter, are cooled by diverting the refrigerant liquid line into the closed controls compartment of the outdoor cabinet section and by passing the liquid line through a block of material therein upon which the compressor speed control components are mounted. The heat generated by the speed control components is transferred through the block of material and ultimately into the liquid refrigerant which is pumped through the liquid line by the operation of the compressor. Heat generated in the controls compartment is therefore removed from the compartment by system refrigerant in an manner which does not, to any significant degree, adversely affect the overall operation and efficiency of the system.

Abstract: A first portion of a pitot tube-like device faces into the incoming stream of suction gas which enters the hermetic shell of a low-side reciprocating compressor. A second portion of the device extends downwardly toward the oil sump within the shell. The device terminates in a third portion which defines a plurality of apertures and which is immersed in the oil within the sump. The dynamic pressure or velocity head of the incoming suction gas stream is converted within the device to static pressure as a result of the resistance to flow through the device. The resistance to flow through the device is a function of, among other things, the static head at the immersed aperture locations.

Abstract: A thrust bearing for use between two parallel plates in relative orbital motion. The bearing includes a plurality of rollers disposed between the plates. Each roller comprises two opposing cones joined at their base with one cone in rolling line contact with one plate and the other cone in rolling line contact with the other plate. As one plate orbits relative to the other, each rolling line contact sweeps a circular area on its respective plate.

Abstract: A control and method for varying the capacity of a centrifugal chiller system used to cool a liquid to a setpoint temperature. The control permits the user to select the setpoint, the control gain, and two variables that determine a first deadband and a second relatively wider deadband about the setpoint. If the absolute value of the difference (error) between the actual fluid temperature and the septoint is increasing, the control uses the first deadband, and conversely, if the error is decreasing, it uses the second deadband to vary chiller capacity. The control also permits the user to select a limit for various operating parameters associated with protective shutdown of the system to avoid catastrophic failure, and adjusts the chiller capacity according to one of two predefined functions of the deviation of the operating parameter from its limit, dependent on whether that deviation is greater or less than a predefined deadband.

Abstract: A combination heat shield/gasket is disposed between abutting components in a reciprocating compressor. The heat shield/gasket includes strategically located protuberances, at locations where the components do not directly abut, the tips of which contact one of the components causing the heat shield/gasket to locally deflect away from the contacted component. The deflection of the heat shield/gasket at such non-abutting locations causes a dead space to be created between the component contacted by the tip of the protuberance and the heat shield/gasket. The dead space so created is a barrier to the transfer of heat, as is the heat shield/gasket itself, from the component contacted by the protruberances to the area on the side of the heat shield/gasket opposite that side on which the dead space is created.

Abstract: A heat exchanger tube assembly having one end of a copper tube soldered to the end of an aluminum tube, and a method of minimizing galvanic corrosion at the soldered joint. The aluminum tube, having a roughened inner surface for enhanced heat transfer, fits inside the copper tube at the soldered joint. A heat shrinkable thermoplastic tube having a thermosetting adhesive inner coating is placed around the joint and then heated. The heat shrinks the thermoplastic tube, causing it to contract and to adhere tightly against and around the joint. The plastic tube with its adhesive inner coating protects the joint from atmospheric moisture and thus inhibits galvanic corrosion that would eventually create a leak in the tube joint.

Abstract: A retrofit assembly for adapting two replacement rooftop air handling units to a multizone installation that originally had only one air handling unit. The two replacement units include one heating unit and one cooling unit, while the original unit typically had provided both heating and cooling to several zones in the building. The retrofit assembly includes a valve manifold and a curb adaptor that make it possible to use the building's existing roof curb and air ducts. The curb adaptor supports the cooling unit on top of the existing roof curb and includes an air duct for conveying air from the existing return air ducts in the building to the inlet of the cooling unit. The heating unit is mounted on its own separate roof curb and the valve manifold receives the air discharged from both replacement units and directs it into the existing plurality of supply air ducts which further convey the air to the plurality of zones in the building.

Abstract: An air conditioning system is disclosed in which the air conditioning capacity is stepped to a lower level upon reduced sensible air conditioning demand. The stepped reduction involves both a stepped reduction of blower capacity and a stepped change of the heat exchange fluid flow at the heat exchanger modifying the temperature of the air. Several embodiments are disclosed.

Abstract: An air-to-air heat pump system includes a refrigerant-liquid heat exchanger for heating a liquid. The system is capable of (1) space cooling, or (2) space heating, or (3) liquid heating without affecting the condition of an indoor space, or (4) simultaneous space cooling and liquid heating, or (5) simultaneous space heating and liquid heating, or (6) defrosting the outdoor heat exchanger without affecting the condition of an indoor space by utilizing heat supplied from a stored previously-heated liquid.

Abstract: A screw rotor profile for both male and female rotors is generated from a single rack in which each individual rack segment includes four discrete circular arc segments and two discrete straight line segments. The leading and trailing flanks of the lobes of both the male and female rotors generated by the rack include involute portions disposed between tangent circular-arc-generated portions. A method for developing the rack is also disclosed.

Abstract: Apparatus for separating a liquid from a gas includes a cylindrical separator element disposed in a sealed housing. The separator element includes a helical ramp wrapped around a cylindrical column both of which are disposed in a hollow cylindrical shell. The ramp, column and shell cooperate to define a helical passage through which a liquid-gas mixture is constrained to pass between an inlet and outlet at opposing ends of the separator element. A liquid-gas mixture entering the separator element is imparted a swirling motion as it passes through the helical passage within the separator element. Liquid entrained in the mixture migrates radially outward within the separator element and passes through the permeable shell. The separated liquid drains by force of gravity to a sump area defined by the sealed housing from where it can be drained for re-use.

Abstract: In a hermetic compressor, a seal extending between a suction port and a second port in fluid communication with an internal chamber disposed adjacent an electric motor. The seal includes a cylindrical tubular member, one end of which slidingly fits within the suction port. A slotted conical flange on the other end of the tubular member fits around the port on the chamber. When a suction line is attached to the suction port with a threaded nut and fitting, it abuts against the projecting end of the tubular member, forcing the cone-shaped flange on the other end of the tubular member to flatten slightly as it seats against the external surface of the chamber. Most of the suction fluid entering the suction port flows through the tubular member into the chamber and through the electric motor to cool it. The compliant flange on the seal allows substantial tolerance in the spacing and angular displacement of the port in the internal chamber relative to the suction port in the shell.

Abstract: A microcomputer based defrost control for a heat pump system that "learns" from previous defrost cycles to achieve optimum defrost control at each of a plurality of outdoor temperature ranges, even if the heat pump system operating parameters change due to system aging. At the conclusion of each defrost cycle, the control determines the differential temperature between the outdoor ambient air and the outdoor heat exchanger and compares that value to a value stored in microcomputer memory representing a previous best such post-defrost differential temperature for the same ambient air temperature range. The control then calculates a defrost differential temperature initiate value, corrected to compensate for any loss of defrost performance indicated by the current post-defrost cycle differential temperature.

Abstract: Liquid refrigerant produced in the condenser of a refrigeration system is directed into an expansion device. The expansion device throttles the high pressure liquid refrigerant into the compressor drive motor housing of the compressor assembly within the refrigeration system. Upon entering the motor housing a first portion of the liquid refrigerant flashes into gas at a pressure intermediate compressor suction and discharge pressure. The portion of refrigerant which remains in the liquid state is directed into a jacket surrounding the stator of the compressor drive motor. As the jacket fills with liquid refrigerant, a portion of the refrigerant is directed through passages in the motor stator into contact with the motor rotor. Liquid refrigerant overflowing the jacket and flowing out the ends of the motor through the gap between the rotor and stator drains to the lowermost portion of the motor housing from where it is directed to a second expansion device.

Abstract: A scroll compressor enclosed in a hermetic shell, wherein part of the volume enclosed by the shell is at suction pressure and part is at discharge pressure. The compressor includes both a stationary and a driven scroll plate, with intermeshed involute wrap elements attached to the plates for defining pockets in which fluid is compressed as a drive shaft connected to the driven plate causes it to orbit relative to the stationary scroll plate. A passage disposed within the driven plate and adjacent its axial center conveys compressed fluid through the plate and into a cavity formed in the end of the drive shaft. Oil entrained in the compressed fluid is thrown radially outward within the cavity, due to centrifugal force, and is thereby separated from the compressed fluid. The oil then flows through an adjacent bearing, and is thrown radially outward, creating a spray that impinges on a seal which abuts the back surface of the driven scroll plate.

Abstract: A heat exchanger of the shell and tube type particularly suitable as an intercooler between compression stages of a compressor is disclosed. The heat exchanger includes a generally cylindrical shell having first and second coil banks disposed therein. The banks are spaced from each other and from the wall of the shell. The incoming fluid flows between the heat exchange coil banks and outwardly therethrough, passing in heat exchange relationship with a fluid flowing through the coils. The fluid velocity is reduced, substantially minimizing carryover of liquid in the fluid, and directional changes in the fluid flow causes disentrainment of liquid. A sump is provided in the bottom of the heat exchanger for removing the condensed liquids, and separate demistors or separators are not required. Access to the coils for cleaning and/or servicing may be had through a manway disposed in the shell, or through an openable end of the shell.

Abstract: A microprocessor based control for tempering supply air in a multi-stage temperature conditioning system. The temperature conditioning stages are normally controlled in response to a comfort temperature sensor to maintain the zone at a setpoint. However, if a sensor in the supply airstream indicates that the temperature of the supply air is less than a predetermined minimum, the primary control algorithm is overridden and the temperature conditioning stages are controlled to increase the supply air temperature. Tempering the supply air prevents personal discomfort due to excessively cold air being supplied to the zone.

Abstract: A nozzle for a shell of a heat exchanger particularly useful as the outlet nozzle thereof in which an outlet pipe extends into the shell, and a bellmouth orifice is provided at the end of the pipe. A mounting plate is attached to the orifice and extends between the perimeter of the orifice and the shell, for minimizing the flow of fluid behind the orifice. Vents are provided in the plate for equalizing the pressures on opposite sides of the plates.