Abstract: A tip seal back-up member is disclosed for use in fluid apparatus of the scroll type, which member comprises a strip of material extending longitudinally in generally spiroidal configuration about a reference axis and having a preformed configuration such that its radially inner and outer edge portions are disposed axially with respect to each other. The strip of material comprises an elastic material such that as one of the edge portions is displaced axially toward the other, an opposing spring force is developed. In operation, the back-up member is disposed within a groove located in a tip surface of a wrap element in fluid apparatus of the scroll type, between a bottom wall of the groove and a tip seal. Preferably, the strip of material is generally flat between its radially inner and outer edge portions and is constructed from steel.

Abstract: A wrap element and tip seal are disclosed for use in fluid apparatus of the scroll type which include a wrap element having a groove disposed within its tip surface of spiroidal configuration generally conforming to that of the wrap element. A tip seal is disposed within the groove and comprises a plurality of strips of material disposed at least partially within the groove and arranged in side-by-side relationship at least partially across the width of the groove, each said strip extending along a longitudinal axis about the spiroidal configuration of the groove. By fabricating the seal from a plurality of strips of material, the necessity for expensive machining operations is obviated while a seal is provided which is relatively flexible in a radial direction as to accommodate the precise groove shape, while remaining relatively inflexible in an axial direction so as to provide the desired sealing characteristics.

Abstract: A rolling thrust bearing for use in a scroll type positive fluid displacement apparatus is disclosed. In the invention, a plurality of ball bearings spaced apart in cavities formed in a bearing cage are operative to transmit an axial force between a supporting frame and an orbiting scroll member. The bearing cage rotates within a groove in which it is seated due to frictional forces between its flank surfaces and the sides of the groove. In a first embodiment, the diameter of the cavities is substantially larger than the diameter of the ball bearings, and the bearings are free to orbit within the cavities as the bearing cage rotates. In the second embodiment, the cavities are only slightly larger in diameter than the ball bearings, but the radial width of the bearing cage is substantially less than the width of the groove, and the bearing cage and the ball bearings together describe an epicycloidal path about the central axis of the bearing cage.

Abstract: A positive fluid displacement apparatus of the scroll type, having a swing link for translating the rotational motion of a drive shaft into the relative orbital motion of two parallel end plates. The facing surfaces of the parallel plates have involute wrap elements attached in fixed angular, intermeshed relationship with each other. Contacting surfaces of the parallel plates and wrap elements define pockets of fluid which are subjected to changes of pressure and volume as the pockets are caused to move between an inlet and an outlet by the orbital motion of the plates.A flexible member of resilient material connects a crank post on the drive shaft with the swing link and transfers the driving force of the drive shaft to the swing link. The flex member is rigid in tension, but flexible in bending. By its spring force, the flex member biases the wrap elements slightly apart when the drive shaft is not rotating, to reduce the driving torque required at start-up of the scroll apparatus.

Abstract: An involute and tip seal for use in a positive fluid displacement apparatus of the scroll type. A scroll machine wrap element of general spiral configuration about an axis includes a radially inner and outer flank surface terminating in a tip. In the tip, a groove is formed which runs in the longitudinal direction of the wrap element and substantially conforms to its spiral shape. A plurality of material strips, generally coaligned in parallel side-by-side relationship, are disposed within the spiral groove of the involute wrap. One or more of the strips includes a plurality of notches along at least one of the two axial edges. These notches, in conjunction with one or more of the adjacent strips and a flat surface against which the notched edge abuts, define a plurality of labyrinth pockets longitudinally spaced along the strips. The labyrinth surface improves both longitudinal and transverse fluid sealing of the involute tip seal.

Abstract: A control and method for defrosting the outdoor heat exchanger of an air source heat pump. A defrost cycle is initiated when ice and frost have accumulated on the outdoor heat exchanger sufficiently such that, as a function of the indoor temperature of a comfort zone, the maximum permissible heat transfer degradation at which the efficiency and reliability of the temperature conditioning system are optimized, has occurred. Heat transfer degradation is determined from the outdoor ambient air temperature and the temperature of either the outdoor heat exchanger, or the compressor suction line. If the temperature of the outdoor heat exchanger or the suction line is less than a predetermined value, a deferred defrost cycle is initiated wherein the defrost cycle starts after a fixed time interval has elapsed.

Abstract: A compressor oil pump with integral contaminant collector and helical vane for improved pumping efficiency. A generally cone-shaped pick-up tube is adapted to be attached to the lower end of a hollow rotatably driven vertical shaft for rotation thereby about its longitudinal axis. The lower end of the pick-up tube includes an inlet opening which extends into a reservoir of oil. An annular contaminant collection groove is disposed circumferentially within the wall of the pick-up tube forming a pocket. This groove collects and retains contaminant particles contained in oil which is swept up the tapered interior surface of the tube due to the centrifugal force developed by its rotation. The helical vane is provided in the interior of the pick-up tube to increase its pumping efficiency. The vane acts to accelerate the oil to the rotational speed of the pump, thereby improving the volumetric flow output from the pump.

Abstract: An oil distribution system for lubricating bearings in a scroll compressor. The system includes an oil collector cup attached to the lower surface of a swing link. Oil pumped through an internal passage in a rotating drive shaft is retained in the collector cup when the compressor stops, so that it is immediately available to lubricate adjacent bearings upon restart of the machine. Also disclosed in two embodiments are means for distributing and properly allocating the flow of oil between a thrust bearing and a swing link bearing.

Abstract: A heat pump refrigeration circuit for heating a space, cooling a space, heating a liquid, heating a space and heating a liquid or for cooling a space and heating a liquid in which indoor and outdoor heat exchangers, a liquid heat exchanger and liquid supply means, compressor, conduit and valve means are provided. The liquid heat exchanger is disposed in the hot vapor line, and liquid is circulated therethrough when liquid heating is required. The liquid heat exchanger may be used as a desuperheater or as a condenser, and the indoor and outdoor heat exchangers may be used as condensers or evaporators, depending upon the path of refrigerant flow, as determined by the valve positions. Bypassed heat exchangers are vented to compressor suction for maintaining refrigerant charge control.

Abstract: A heat pump system and method, wherein the system may be operated in cascade fashion to heat water using heat extracted from relatively cold outdoor ambient air, or in non-cascade fashion to provide supplemental heating or cooling in a comfort zone. The system uses a first and a second refrigerant fluid with separate compression cycle loops passing in heat transfer relationship through a tri-fluid heat exchanger. In a first mode of operation, the first refrigerant fluid condensed while heating water is vaporized in the tri-fluid heat exchanger to cool air supplied to the comfort zone, and in a second mode the first refrigerant fluid is vaporized by heat rejected from condensing the second refrigerant fluid. In a third mode, wherein only the second refrigerant loop is operative, air passing through the tri-fluid heat exchanger to the comfort zone is heated by condensation of the compressed second refrigerant fluid.

Abstract: A gas compressor of the scroll type is disclosed wherein means are provided for reducing its degree of compression as it starts from a standing start in order to reduce the initial starting torque required. To this end, passage means are provided which extend through the end plate means of the compressor from a location in communication with the closed moving volumes defined between the wrap elements to a second location in communication with working gas normally at discharge pressure during operation of the compressor. Valve means are associated with the passage means for permitting flow therethrough when the pressure within the closed moving volumes exceeds the discharge pressure at said second location as the compressor starts from a standing start, and for blocking flow therethrough during operation of the compressor when discharge pressure normally exceeds the pressure in the closed moving volumes.

Abstract: A gas compressor of the scroll type is disclosed wherein unloader means are provided for selectively varying its capacity by effectively delaying the point at which the closed moving volumes defined between the wrap elements begin compression. To this end, passage means extend through the end plate means of the compressor from a location in communication with the closed moving volumes to a location in communication with working gas normally at suction pressure during operation of the compressor. Valve means are provided for selectively blocking flow through the aforementioned passage means, whereby the compressor operates at a relatively high capacity; and for permitting flow through the passage means, whereby gas is exhausted via the passage means to suction pressure as the closed moving volumes progress radially inwardly to a predetermined position at which compression is permitted to begin.

Abstract: A multi-cylinder reciprocating compressor is disclosed which is provided with an unloader valve for blocking the flow of suction gas to at least one of the cylinders to reduce the compressor capacity. The unloader valve is disposed at one end of a cylinder bank and comprises an unloader piston and an unloader port which is an integral part of the cylinder bank. A chamber in which the unloader piston and unloader port are located is formed in the cylinder bank with its axial center in parallel alignment with the axial center of all the cylinders in that bank. This improved efficiency, facilitates ease of manufacture, and reduces associated costs.

Abstract: A solid-state control for a variable air volume (VAV) temperature conditioning system adapted to control a plurality of refrigerant cooling stages, and in particular, to modulate an outdoor air economizer. The control includes both an outdoor ambient air and a discharge air temperature sensor. Further included are means for selectively modulating the economizer either in response to the deviation of the discharge air temperature from a setpoint or in response to the discharge air temperature, depending upon the relative magnitudes of the outdoor and discharge air temperature, and upon one or more stages of cooling being energized.

Abstract: A heat exchange surface having nucleate boiling cavities defined by subsurface cavities in combination with a thin porous coating. A preferred embodiment of the heat exchange surface includes a plurality of helical fins formed on the outer surface of a metallic tube, the tips of which are deformed by rolling to define gaps opening into fin cavities between adjacent fins. A porous open-celled coating flame-sprayed on the deformed portion of the fins substantially bridges these gaps, except at random open points caused by the inherent porosity of the coating. These openings in the porous coating in combination with the fin cavities provide nucleate boiling sites which promote efficient heat transfer for boiling a liquid.

Abstract: A heat transfer surface for boiling liquid refrigerant 11 and its equivalents and method for producing the surface. The surface comprises a porous, open-cell coating at least 15 mils thick, of oxidized metallic particles which are flame-sprayed onto a metal substrate. This surface includes a substantial number of nucleate boiling cavities having an equivalent radius in the range of 1.5 to 4 mils, which are the result of one or more of the following conditions in the flame-spraying process: (1) The flame-spraying nozzle is oriented so that the metallic particles impact the metal substrate at an angle in the range of 30.degree. to 75.degree.; (2) The metal substrate is preheated to a temperature which is at least 600.degree. F., but below the melting point of the substrate; and (3) The flame-spraying apparatus is positioned such that the metallic particles travel from 3 to 6 inches before impacting the substrate.

Abstract: A reciprocating gas compressor of the multicylinder, radial type is disclosed which includes unloading means for selectively shutting off suction gas flow to one or more of the cylinders in order to vary the capacity of the compressor. The unloading means include a valve element having a flat, planar surface which is movable between first and second positions with respect to a generally planar valve seat surrounding the inlet of the suction flow passage means, which inlet is spaced radially from the crankshaft axis and lies in a plane substantially perpendicular thereto.

Abstract: Apparatus and method for controlling a temperature conditioning system in which a plurality of stages of temperature conditioning apparatus may be selectively energized to meet a temperature conditioning demand in a comfort zone into which the flow of temperature conditioned air is varied in response to temperature therein. Control means are operative to determine the differential temperature of the return air and the supply air and to energize and de-energize stages of temperature conditioning in response thereto. Means are provided to measure the outdoor ambient temperature, thereby enabling the control means to determine the heating capacity of an ambient air source heat pump relative to the outdoor ambient air temperature, and to energize and de-energize heating stages as appropriate, to meet heating demand.

Abstract: Apparatus for rotating a fluid impeller of a centrifugal or axial flow fan, at multiple speeds. A fan is provided with a first and a second electric motor for drivingly rotating a fluid impeller at relatively fast and slow speeds, respectively. The rotor of the first motor directly drives the fluid impeller; the second motor is connected to the impeller shaft of the fan through a belt drive, with pulleys sized to reduce the impeller's rotational speed relative to that of the second motor.Only one of the motors is provided with a start winding. Control means selectively energize the first and second motors, and are operative to energize the one motor long enough to bring the other motor up to operating speed.

Abstract: A sensor for providing a differential pressure signal indicative of the average relative rate of flow of a fluid through a duct. Two tubular members are provided, each of which are formed in a loop oriented transverse to the fluid flow and each having a plurality of spaced-apart orifices along their length. In one of the tubular members, the orifices face upstream toward the impinging fluid flow; in the other, the orifices face downstream. The difference between the pressures developed within the two tubular members as a result of the orientation of these orifices relative to fluid flow is indicative of the average rate of fluid flow in the duct.