The Rovac Corporation

Avco Corporation

Wayne C Shank

Thomas C Edwards

A refrigeration system including a compressor, a condenser, an expansion valve and an evaporator with controls and interconnections to provide a system operating in a vapor refrigeration cycle containing a refrigerant or combination thereof selected from a group of low vapor pressure refrigerants having boiling points anywhere from about 10 degrees F. to 83 degrees F. and the compressor comprising an open system constrained rotary vane compressor having a ratio Q/D of cooling capacity per unit of displacement anywhere in the range from about 8,000 to 30,000 FT-LB per HR/FT.sup.3 per HR determined by the refrigerant or combination thereof in the system and according to a specified formula.

Vapor refrigeration cycle system with constrained rotary vane compressor

A rotary compressor having a housing defining a chamber with a curved outer wall of substantially elliptical profile containing a rotor of cylindrical shape having a plurality of vanes profiled to fit the chamber and radially slidable in grooves in the rotor to define enclosed compartments between them. Each vane has a pair of axially extending stubshafts having rollers respectively mounted thereon. Roller tracks formed in the end walls of the chamber accommodate the rollers for guiding the vanes so that the outer edges of the vanes follow the outer wall of the chamber in closely spaced engagement. Inlet and outlet ports located in the curved outer wall of the chamber closely straddle a reference region. The rotor has its axis laterally offset from the chamber for engagement at the reference region for sealing between the ports, the rotor axis being offset toward the outlet port and being spaced along both the major and minor axes of the elliptical profile by sufficient amounts that each vane undergoes but a single in and out stroke during each revolution of the rotor notwithstanding the elliptical nature of the chamber. In the preferred construction the rollers ride in grooves having radially opposed walls formed in the respective end walls of the chamber, with the radially inward wall having substantially constant radial clearance with respect to the contained rollers thereby to determine the amount that each vane can move radially inward under starting conditions and in the face of 'slugging'.

Vane type compressor having elliptical stator with doubly-offset rotor

A rotary machine having a cavity in the form of a doubly truncated sphere having a rotor of hollow construction mounted therein, the cavity being symmetric about a vane axis which is canted with respect to the rotor axis. The rotor includes an integral Saturn-like ring extending symmetrically about its axis dividing the cavity into first and second sides each of annular wedge shape having thick and thin portions arranged in complementary fashion. The rotor has four radial slots aligned with the shaft axis to divide the rotor into 90 degree sectors, the slots being occupied by first and second blades with each blade defining a pair of vanes which separate the sides of the cavity into successive chambers which vary cyclically in volume as the shaft rotates. A relatively thin auxiliary shaft extends axially through the hollow of the rotor. An auxiliary centering ball is telescoped over the auxiliary shaft at the point of intersection of the axes. For engaging the ball the blades have at their centers respective C-shaped recesses facing mutually inwardly in overlapping relation, each recess being radially dimensioned to snugly embrace the ball in the longitudinal dimension thereby to keep the blades centered in positions of equalized radial clearance with respect to the wall of the cavity. In the preferred embodiment the recesses are so formed that the ball is held relatively captive in the plane of each blade so that each blade is positioned in the endwise direction by the companion blade.

Rotary machine of canted vane type having centering ball

A compressor-expander having a vaned rotor in which the vanes rotate about an axis which is canted with respect to the rotor axis. The housing of the device has a disc-shaped main cavity having adjacent hub recesses which are concentrically spherical. The cavity is in the form of a doubly truncated sphere canted with respect to the shaft axis. The rotor has a central spherical portion for mating with the recesses and includes an integral Saturn-like ring extending to the outer wall of the cavity to divide the cavity into first and second complementary sides of annular wedge shape. The vanes occupy radially extending slots in the rotor and serve to separate each side into successive chambers which vary cyclically in volume as the shaft rotates without requiring the vanes to bodily reciprocate either radially or axially. Each side is provided with inlet and outlet ports. The vanes have laterally projecting shoulders along their lateral edges formed to mate with the respective concave spherical surfaces in the housing. The vanes comprising each pair are interconnected in coplanar relation by a central connector, the central connectors being offset in the axial direction for crossing one another in the hollow of the rotor. The vanes have lateral edges lying in a cylindrical locus and have a thickness which is related to the thickness of the cavity and the angle of cant of the vane axis.

Compressor-expander of the vane type having canted vane cavity

A rotary compressor for use in air conditioning or the like including a housing having a chamber with a cylindrical rotor journaled therein, the rotor having a set of vanes radially slidable to define enclosed compartments between them. The curved outer wall of chamber has a reference region separating the chamber into inlet and outlet sides having inlet and outlet ports in straddling relation. The rotor has its axis laterally offset from the chamber axis to produce sealing at the reference region. The curved wall of the chamber on the inlet side is of substantially elliptical profile with the major axis of the ellipse generally centered on the inlet side and with the inlet port extending to a point of cut-off short of the major axis. The curved wall on the outlet side is smoothly continuous and substantially circular in profile. In operation, gas entering the inlet port is charged in a compartment between a pair of vanes at the major elliptical axis and progressively compressed over an arc of compression greater than about 180 degrees for discharge from the outlet port in the compressed state. The outlet port is provided with a circular liner the trailing end of which defines the point of initial discharge from the outlet port, the liner being peripherally shiftable to vary the pressure at which the gas is discharged.

Vane type compressor employing elliptical-circular profile

Herein disclosed is the combination of an aerodynamic blade having a root formed with outwardly curved shoulders and a transverse curved indentation, a rotor disc formed with a blade root receiving slot having curved complementary retaining surfaces in contact with those shoulders and an elastic split metallic roll pin disposed between the indentation and disc to provide damping, the radii of the curved shoulders and retaining surfaces being generated from an axis below said indentation.

Rooted aerodynamic blade and elastic roll pin damper construction

A negative torque sensing and control system is disclosed which is useful with a differential geared or fixed shaft gas turbine engine of the type installed in general aviation aircraft. Negative torque is sensed in the gear train between the propeller and the aircraft engine whenever there is a powerplant failure. When the reverse torque exceeds a selected threshold, hydraulic valves are actuated which remove oil pressure from the pitch control mechanism of the propeller. Loss of oil pressure causes the propeller to assume the feathered position.

Negative torque sensor for a gas turbine engine

A two-stage diffuser is disclosed which is intended to be used with a high pressure ratio centrifugal compressor. The first stage comprises a vaneless diffuser passage having rotating sidewalls that freely turn on bearings mounted coaxially with the compressor rotor. The second stage comprises a stationary vaned-type diffuser. In combination, the two stages provide a compact diffuser having improved efficiency. Gas flow leaving the compressor from the periphery of the impeller at supersonic speed contacts the moving sidewalls of the rotary diffuser stage. By having these walls travel at nearly half the speed of the impeller, relative difference in speed between the gas and the walls is subsonic, hence, no shock wave occurs. Expansion of the gas in the first rotary diffuser stage makes it possible to deliver subsonic gas to the vaned second stage.

Growing community of inventors

Tucson, AZ, United States of America

Wayne C Shank