Abstract: An evaporative emissions control system for small internal combustion engines includes a control valve associated with a fuel line and with a vent line which each connect the fuel tank to the carburetor. When the engine is not running, the control valve automatically closes the vent line and the fuel line, thereby trapping fuel vapors within the fuel tank and vent line and preventing the supply of liquid fuel to the carburetor. Upon engine start up, actuation of a bail assembly or vacuum produced within the carburetor causes the control valve to open the vent line and the fuel line, venting fuel vapors from the fuel tank through the fuel line to the carburetor for consumption by the engine, and opening the supply of liquid fuel from the fuel tank to the carburetor.

Abstract: Mechanical compression and vacuum release mechanisms for internal combustion engines. The compression and vacuum release mechanism may include a pair of centrifugally responsive flyweights pivotally mounted to the cam gear. One of the flyweights actuates a vacuum release member having a vacuum release cam and the other of the flyweights actuates a compression release member having a compression release cam. In another embodiment, the compression and vacuum release mechanism includes a single flyweight having structure associated therewith to actuate a vacuum release member and a compression release member having respective vacuum and compression release cams. The compression and vacuum release cams are in lifting engagement with the valve actuation structure of one of the intake or exhaust valves of the engine during engine starting to relieve compression and vacuum within the combustion chamber and thereby facilitate easier engine starting.

Abstract: A multi-stage compressor having a shaft with two eccentrics that are offset with respect to the shaft axis of rotation in substantially the same radial direction, compressor also having two vanes oriented in substantially opposite radial directions with respect to shaft axis. Also, a multi-stage compressor having a first-stage cylinder for compressing a fluid, e.g., a refrigerant, from a low pressure to an intermediate pressure, a second-stage cylinder for compressing the refrigerant from the intermediate pressure to a high pressure, and a housing having an intermediate-pressure refrigerant outlet in direct fluid communication with the first-stage cylinder and an intermediate-pressure refrigerant return inlet in fluid communication with the interior of the compressor housing. Also, a compressor having a vane operably engaged with a shaft eccentric and a spring biasing the vane toward the eccentric, wherein the amount of biasing force applied by the spring is adjustable.

Abstract: A refrigeration system for freezing fluid in a tray during a first operating mode and defrosting the ice during a second operating mode to facilitate the removal of the ice from the tray. In the first operating mode, refrigerant circulates through a circuit in a first direction and, in the second mode, the flow of refrigerant is reversed in a portion of the circuit. In the first operating mode, cool refrigerant exits an expansion device in the circuit and enters into the evaporator to freeze a fluid in the tray. In the second operating mode, a valve is operated to permit warm refrigerant exiting the compressor to enter into the evaporator to melt a portion of the ice reversing the flow of refrigerant therein. A second valve permits the reverse flow of refrigerant through the evaporator to return to the compressor inlet instead of passing through the expansion device and condenser.

Abstract: A reciprocating piston compressor having a suction muffler and a pair of discharge mufflers to attenuate noise created by the primary pumping frequency in the primary pumping pulse. The suction muffler is disposed along a suction tube extending between the motor cap and the cylinder head of the compressor. The discharge mufflers are positioned in series within the compressor to receive discharge gases from the compression mechanism and are spaced one quarter of a wavelength from each other so as to sequentially diminish the problematic or noisy frequencies created during compressor operation. The motor/compressor assembly including the motor and compression mechanism is mounted to the interior surface of the compressor housing by spring mounts. These mounted are secured to the housing to define the position of the nodes and anti-nodes of the frequency created in the housing to reduce noise produced by natural frequencies during compressor operation.

Abstract: A mounting bracket for a compressor. The mounting bracket includes a mounting member and an elongate bracing member. The mounting member is secured to the housing of the compressor has a central support section in substantial registry with the housing. The mounting member includes two legs which extend from opposite ends of the central support section. The first and second legs respectively include first and second distal portions. The bracing member may be secured to the mounting member with two swaged connections. The swaged connections each define an aperture through the bracing member and the mounting member. A method of mounting a compressor is also provided. The method utilizes a mounting bracket having a bracing member which is secured to a mounting member by deforming at least one of the bracing member and the mounting member into engagement with the other of the bracing member and the mounting member.

Abstract: A multi-layered compressor housing and method of manufacture is provided. The housing defines an interior space and includes first and second layers having first and second major surfaces respectivley. The first and second layers are secured together by the frictional engagement of the first and second major surfaces which each substantially enclose the interior space defined by the housing. The housing may be manufactured by placing first and second layers of sheet stock material in mutual facing engagement wherein the two layers are relatively moveable. The first and second relatively moveable layers are then simultaneously formed into a non-planar shape defining at least a portion of the housing. A compressor is then mounted in the housing and the housing is hermetically sealed. The simultaneous forming of the first and second layers into a non-planar shape causes the frictional engagement of the layers whereby the layers are secured together.

Abstract: A modular hydrostatic transaxle includes an axle module removably connected to a hydrostatic transmission module. The axle module includes a differential connected to a reduction gear train and disposed in an axle casing. A pair of axles are connected to the differential and supported within the axle casing. The hydrostatic transmission module comprises a transmission casing separate from the axle casing and hydraulically connected pump and motor disposed in the transmission casing. The motor output connection includes a shaft piloted to an input drive of the reduction gear train, which constitutes the alignment mechanism of the transmission and axle modules. The pump and motor cylinder barrels are hydraulically connected through the pump and motor block at 90° orientation, and a portion of the pump and motor block forms an inclined surface which supports a face of a thrust bearing. At least one homogeneous low friction bearing strip is confined between the swash plate and the interior portion of the casing.

Abstract: A compressor assembly including a cylinder block defining first and second cavity portions. A central axis extends through first and second cavity portions. A compressible fluid respectively enters and exits the first cavity portion through an inlet and outlet. A piston is reciprocatingly disposed along the central axis and includes first and second piston portions which are at least partially disposed within the first and second cavity portions, respectively. The first piston portion defines a compression chamber within the first cavity portion. Reciprocation of the piston compresses the fluid within compression chamber. The second piston portion has a radial outer surface at least partially engageable with a sidewall of second cavity portion whereby forces transverse to the central axis are transferable between the radial outer surface and the sidewall. A variable volume space is defined by the second piston and cavity portions. A vent passage communicates with the variable volume space.

Abstract: Mechanical compression and vacuum release mechanisms which are of simple construction and which significantly reduce the effort required to start an internal combustion engine. In several embodiments, the compression and vacuum release mechanisms include a centrifugally responsive flyweight pivotally mounted to the camshaft, the flyweight coupled to a pair of compression and vacuum release pins which include respective compression and vacuum release cams that are in lifting engagement with the valve actuation structure of one of the intake or exhaust valves of the engine during engine starting to relieve compression and vacuum within the combustion chamber and thereby facilitate easier engine starting. After the engine is started and reaches running speed, the flyweight pivots responsive to centrifugal force and in turn pivots the compression and vacuum release cams out of engagement with the valve actuation structure of the intake or exhaust valve to allow the engine to operate normally.

Abstract: A secondary engine speed control mechanism for small internal combustion engines, including an operator control which is manually operable to override an engine running speed which is set by the engine's primary speed control mechanism and governed by the governor. The secondary speed control mechanism may be selectively actuated by the operator in anticipation of an increased engine load to provide a temporary increase or “boost” to engine speed above the set, governed engine running speed. The secondary speed control mechanism may include an operator actuated, trigger-type mechanism located on the handle of an implement with which the engine is used.

Abstract: An evaporative emissions control system for small internal combustion engines. The system generally includes a charcoal canister and a carburetor with a fuel circuit shutoff valve. The charcoal canister is in fluid communication with the air space above the liquid fuel within the engine fuel tank, and optionally, with the air space above the liquid fuel within the fuel bowl of a fuel bowl-type carburetor. The charcoal canister contains charcoal media which absorbs fuel vapors when the engine is not running. During running of the engine, vacuum within the carburetor induces a flow of atmospheric air through the charcoal canister to purge the collected fuel vapors from the charcoal media, and the fuel vapors pass into the engine for consumption. The carburetor of the engine, which may be either a fuel bowl-type carburetor or a diaphragm carburetor, includes a fuel circuit shutoff valve controlled either by a vacuum signal produced within the engine or by a user-actuated mechanical linkage.

Abstract: A compressor assembly including a compression mechanism having a main bearing and a plurality of first pilot holes, and an electric motor comprising a rotor disposed within a stator. The stator has a plurality of second and third pilot holes. Each of the first pilot holes are aligned with one of the second pilot holes. Alignment members are disposed within each pair of aligned first and second pilot holes, whereby the alignment of compression mechanism and stator is maintained. An outboard bearing is secured to the stator, has a plurality of fourth pilot holes and rotatably supports the drive shaft. Each of third pilot holes is aligned with one of the fourth pilot holes. Alignment members are disposed within each pair of third and fourth pilot holes, whereby the alignment of the compression mechanism, the stator and the outboard bearing is maintained.

Abstract: A method of operating a vapor compression system, the vapor compression system defining a closed fluid circuit in which a refrigerant is circulated and having operably disposed therein, in serial order, a compressor, a high pressure heat exchanger, an expansion device and a low pressure heat exchanger. The method includes applying a variable thermal load on a first one of the heat exchangers, monitoring the thermal load placed on the first heat exchanger and controlling the operation of the system to limit the thermal load placed on the first heat exchanger when the thermal load exceeds a predetermined value. A heat exchange subsystem employed to limit the thermal load may include reducing the flow of a heat exchange medium over the heat exchanger or to recirculate the heat exchange medium in a manner which reduces the thermal load on the heat exchanger.

Abstract: A transcritical vapor compression system that includes a fluid circuit circulating a refrigerant in a closed loop. The fluid circuit has operably disposed therein, in serial order, a compressor, a first heat exchanger, a first capillary tube and a second heat exchanger. The compressor compresses the refrigerant from a low pressure to a supercritical pressure. The first heat exchanger is positioned in a high pressure side of the fluid circuit and the second heat exchanger is positioned in a low pressure side of the fluid circuit. The first capillary tube reduces the pressure of the refrigerant from a supercritical pressure to a relatively lower pressure. The refrigerant flows through the first capillary tube at its critical velocity and means for controlling the temperature of the refrigerant in the first capillary tube are provided.

Abstract: A secondary engine speed control mechanism for small internal combustion engines, including an operator control which is manually operable to override an engine running speed which is set by the engine's primary speed control mechanism and governed by the governor. The secondary speed control mechanism may be selectively actuated by the operator in anticipation of an increased engine load to provide a temporary increase or “boost” to engine speed above the set, governed engine running speed. The secondary speed control mechanism may be either mechanically or electrically actuated, and may include an operator actuated, trigger-type mechanism or an electrical switch located on the handle of an implement with which the engine is used.

Abstract: A small internal combustion engine having user interfaces which are formed at least in part of at least one glow-in-the-dark or luminescent material. The user interfaces may include, for example, the carburetor choke and throttle controls, the carburetor primer bulb, the carburetor primer bulb base, the engine ignition key switch, the ignition key, the fuel shut-off valve member, the recoil starter handle, the fuel tank cap, and the oil fill cap.

Abstract: A transcritical vapor compression system that includes a fluid circuit circulating a refrigerant in a closed loop. The fluid circuit has operably disposed therein, in serial order, a compressor, a first heat exchanger, a first capillary tube and a second heat exchanger. The compressor compresses the refrigerant from a low pressure to a supercritical pressure. The first heat exchanger is positioned in a high pressure side of the fluid circuit and the second heat exchanger is positioned in a low pressure side of the fluid circuit. The first capillary tube reduces the pressure of the refrigerant from a supercritical pressure to a relatively lower pressure. The refrigerant flows through the first capillary tube at its critical velocity and means for controlling the temperature of the refrigerant in the first capillary tube are provided.

Abstract: An evaporative emissions control system for small internal combustion engines includes a control valve associated with a fuel line and with a vent line which each connect the fuel tank to the carburetor. When the engine is not running, the control valve automatically closes the vent line and the fuel line, thereby trapping fuel vapors within the fuel tank and vent line and preventing the supply of liquid fuel to the carburetor. Upon engine start up, actuation of a bail assembly or vacuum produced within the carburetor causes the control valve to open the vent line and the fuel line, venting fuel vapors from the fuel tank through the fuel line to the carburetor for consumption by the engine, and opening the supply of liquid fuel from the fuel tank to the carburetor.

Abstract: A rotary compressor comprising a rotor having a plurality of permanent magnets mounted thereon and a stator, where the rotor is aligned with respect to the stator via a magnetic attraction between the permanent magnets and the stator. The compressor includes a housing and is configured such that the rotor does not entirely bear against a top or bottom portion of the compressor housing. The permanent magnets of the rotor are sized and configured such that the magnetic attraction between the magnets and the stator, regardless of whether the stator is energized, positions, or suspends, the rotor substantially intermediate the top and bottom portions of the housing. As a result, less or, possibly, even no friction is experienced between the rotor and the compressor housing which reduces the potential for the rotor to seize or stall and allows the compressor to be operated with little or no oil.