Abstract: The disclosed system includes first and second hermetic shell compressors, one of which always runs while the system is operating and includes unloading means for running at half load, and the other compressor operating at full load or not at all so that four operating capacity steps are available, both of the compressors having shells with suction gas inlets, oil equalizer line ports, and gas exchange line ports being identically sized and located with respect to each other so that standard compressors can be stocked and used in the multiple compressor system while the multiple compressor system is capable of being operated at the varying capacities.

Abstract: The air conditioning unit has a refrigerant evaporator diagonally disposed within the air conditioning cabinet and includes a condensate drain trough at the opposite edges of the evaporator adjacent the front and rear wall of the cabinet, a drain pan assembly extending along the rear wall of the cabinet, and a detachable drip tray which is located in one position on the upstream face side of the evaporator when the cabinet is in a vertical disposition and is located on the upstream face of the evaporator in another position to feed condensate to the other drain trough when the cabinet is in one of its horizontal dispositions, the relationship between the two drain troughs, drain pan and drip tray accommodating the installation of the cabinet in a vertical disposition, and alternatively in a horizontal disposition with either the front or the rear face of the cabinet on top.

Abstract: The invention provides an arrangement for shielding non-metallic motor leads from damage during servicing within the cabinet of a forced air furnace having a double inlet centrifugal blower housing containing a fan wheel and a direct drive motor which is resiliently mounted to the blower housing. The arrangement includes a channel-shaped raceway and a junction box which are aligned on the blower housing support plate in an arrangement permitting the raceway to be secured to both the junction box and the side of the blower housing in a way which does not interfere with the resilient mounting of the motor within the housing. The arrangement is also adapted to accommodate protecting the motor and capacitor leads of an external capacitor type motor.

Abstract: A rotary compressor is provided in which the space between the rotor and the encompassing housing wall is separated into suction and discharge spaces by reciprocating vane assemblies, each of which includes a blade portion having a distal end portion carrying a pivotal shoe, the joint between the shoe and blade being of cylinder and socket character with the blade end forming the cylinder part of the joint and the shoe having a socket cavity for receiving the cylinder. In other forms, the shoe has a generally channel shape in transverse cross section with the leg of the channel facing the compression side having vent holes which reduces the turning movement applied to the shoe under conditions of high differential pressures between one side of the shoe and the other. This arrangement promotes stability and reduces the possibility of loss of equilibrium of the shoe against the moving surface.

Abstract: An arrangement for closing selective areas of the tip portion of a hollow turbine blade having internal serpentine coolant passages is provided by radially extended wall portions at the tip of the blade along at least two sides of the outer ends of each two adjacent internal passages to be closed at the tip, retaining grooves provided in the facing surfaces of the extended wall portions, cover means overlie the outer ends of the selected adjacent passages and have opposite lateral edges received in the retaining grooves, and bond means secure the cover means along the lateral edges to the wall portions. The cover plate means preferably takes the form of two or more separable plates which can be independently inserted into the retaining grooves from an area on the tip portion of the blade which does not have the radially extended walls with retaining grooves therein.

Abstract: A gas turbine combustor of the catalytic reactor type has the catalytic element means formed of a crossflow honeycomb type in which the various series of flow passages extend in oblique relation to each other and to longitudinal axis of the combustor shell so that the combustion gas from different radial locations in a cross section upstream from the catalytic element means is shifted to other radial locations in passing downstream, to promote temperature uniformity of the gas in a radial direction throughout the cross section of the combustor.

Abstract: A vane assembly for a rotary compressor is provided having a shoe for sliding against a relatively moving surface and carried on a blade edge in a cylindrical pivot type joint. The shoe is generally channel-shaped in transverse cross-section and has openings in both of the opposite legs of the shoe. The cylindrical-shaped edge of the blade upon which the shoe is mounted is dimensioned relative to the socket of the shoe receiving the edge to permit movement of the cylindrical edge in a direction away from the web of the shoe under a condition of high differential pressure across the shoe so that a relief passage from the high pressure space on the one side of the shoe to the low pressure space on the other side of the shoe is provided by the openings in the legs of the shoe and the cylindrical edge moved apart from the web of the shoe.

Abstract: A multi-row, finned tube heat exchange coil is made in a process particularly useful where the tubes and end fittings are both of aluminum, by arranging all of the hairpin-shaped tubes with their bights on the one end of the coil along with all of the complex connecting fittings such as tripods, inlet and outlet distributor headers and crossovers, and with the return bends all being arranged at the other end of the coil, and then soldering all of the return bends to the open ends of the tubes at that end of the coil.

Abstract: Damaged tubes are removed from a multi-tube finned coil of the type in which the tubes are expanded into the fins by cutting a helix in the tube wall for the length of the tube from internally of the tube and then pulling the tube out by collapsing the helix upon itself.The tool for accomplishing this has a cutting end portion which has a succession of cutting teeth in a helical array in one rotative direction and with the tips of the cutting teeth successively along the length of the cutting end portion generally progressing radially outwardly from about the internal diameter of the tube to about the external diameter of the tube to be removed, the cutting portion also having a series of flutes extending helically along the length of the cutting end portion in the opposite direction from the helical array of the teeth, the tool being used to carry out the method of cutting a helix into the wall of the tube as the cutting end portion of the tool passes through the length of the tube.

Abstract: A refrigeration condenser has the fan and motor supported in depending relation from an inverted, cup-shaped member centered in the top wall opening through which condenser air flows, the cup being supported from the perimeter of the opening in the top wall of the condenser housing by radial spokes having outer ends connected to the housing and extending in a substantially straight line inwardly to connections with the cup, so that the weight of the motor and fan is borne in part at least by tension in the spokes.

Abstract: The heat pump system includes a first and a second centrifugal compressor arranged in series relation in a system including interstage expansion of the refrigerant. A pair of parallel circuits is provided for controlling the energization of the compressors in a sequence in which the first to start compressor must be energized to obtain completion of the second parallel circuit required for energization of the second to start compressor. The start of the second compressor is delayed for a period permitting the first compressor to come up to speed and the first circuit controlling the energization of the first compressor will be interrupted unless the second compressor has started within a short period of time after the time delay in starting the second compressor.

Abstract: A one way check valve is connected between the suction line and discharge line so that immediately after operation of the reversing valve of the system the momentary high pressure derived from the coil which has been operated at the higher pressure is vented to the discharge line then connected to the coil which had been operating at the lower pressure.

Abstract: A double induction mixing box is provided with damperless openings to each of two opposite side passages in the box and fluidic diverter means between a primary air supply to the box and the opposite side passages is used for controlling the diversion of primary air between the opposite side passages to correspondingly control the proportioning of the induction of air into the two damperless openings from a room air source and from a ceiling plenum air source.

Abstract: A heating and cooling system is provided which includes a reversible heat pump with three refrigerant coils, one of which is in an air duct for the space to be served, another of which is in heat exchange relation with outdoor air, and a third of which is adapted to exchange heat with a heat exchange fluid which is circulated from a heat storage location, the system including valve means in the refrigerant lines for connecting any of the three coils to operate as either an evaporator or a condenser and for connecting either one of the other two coils to operate as a condenser or evaporator, respectively, so that heat can be exchanged in any combination between air in the duct serving the space to be heated, outside air, and the storage fluid.

Abstract: An air conditioning unit of the type adapted for installation externally of the space to be conditioned includes an outer housing separated into internal compartments by interior partition means and includes a belt-driven blower in one compartment for forcing air through heat exchanger means including a refrigerant evaporator, with the motor for driving the blowers being located in a compartment separate from that in which the blowers are located, the motor being cantilever mounted on a wall between the compartments with means provided to fasten the motor so that it may be shifted toward and away from the blowers to adjust belt tension but without uncovering an opening in the wall through which the blower motor shaft projects. Thus motor heat is prevented from mingling with the air which is blown across the refrigerant evaporator.

Abstract: An arrangement for sealing the joints formed between the facing ends of turbine stator segments arranged in an annular array to form a turbine diaphragm is disclosed, the arrangement basically consisting of seal strips formed by at least two bimetal ribbons fastened along their longitudinal centerlines and adapted to deflect away from each other with increasing temperatures, the opposite edges of the strips being disposed in grooves in the facing ends of the stator segments.

Abstract: A tow cart is provided with an arrangement in which the tow or drive pin is adapted to be moved out of engagement with the conveyor drive, in response to a predetermined degree of obstruction to the tow cart, by a spring-loaded overcenter double toggle movable from a cocked to a released position in response to the obstruction, and in which the drive pin is pivotally supported so that it may swing forwardly away from the conveyor drive upon the release. In the cocked position of the toggle mechanism the mechanism restrains the forward pivotal movement of the drive pin.

Abstract: A pair of strips having spaced cutouts therein are placed in lapping relation so the cutouts form openings to receive insulating bushings having circumferential grooves therearound at least some of the end margins of the intervening webs between the cutouts being retroverted to take the form of barbs which in the assembled relation face corresponding barbs of the other strip.

Abstract: A hinge adjustment tool for use on self-closing hinges for kitchen cabinets has the form of a bar of hot rolled steel in which end portions of the bar are displaced out of the plane of the intermediate portion of the bar in opposite directions at an angle of about 45.degree. by a cold bending operation, the end portions each having a slot opening to one of its longitudinal edges and facing in opposite directions, and with the end portions of the tool being hardened by heat treatment.

Abstract: A variable capacity multiple compressor refrigeration system having first and second compressors with the first compressor to be always running when the system is operating and the second compressor to be cycled off or to vary the capacity of the system on while the first compressor continues to run. The discharge lines of both compressors are connected together in parallel to the system and a check valve is provided in the discharge line connection between the compressors to prevent discharge pressure from the operating compressor from entering the discharge port of the nonrunning compressor. A by-pass line connects the suction of the system at the inlet of the second compressor to its discharge line between the check valve and its discharge port and a solenoid valve in the by-pass line is arranged to be closed when the second compressor is running and open when it is cycled off.