Abstract: An oil separator-muffler for a compressor includes an inner chamber with an oil accumulation region and a wall positioned in the inner chamber. The wall defines a separator region and has an impingement surface. The arrangement of the wall in the inner chamber defines flow channels of varying cross-sectional areas. A mixture inlet for the separator-muffler provides a passageway for an oil gaseous refrigerant mixture to flow from the exterior of the separator-muffler into the separator region. The oil is separated from the mixture as the mixture impinges against the impingement surface and flows into the oil accumulation region. A channel in fluid communication with the oil accumulation region provides a passageway for the separated oil from the accumulation region to the exterior of the separator-muffler.

Abstract: A piping structure of an air conditioner causes a looped main piping connected to a compressor of an outdoor unit of the air conditioner to be branched into two or more branch pipings within a predetermined interval of the main piping and cause the branch pipings to be jointed at an arbitrary location. According to the piping structure, it is possible to reduce a vibration by an interference phenomenon, which is generated when either a refrigerant pulsation or a periodic vibration of the compressor is divided and then combined.

Abstract: A device is provided for dampening compressor-induced vibration in an air conditioning system of the type having an indoor unit, an outdoor unit and a refrigerant conduit therebetween. The outdoor unit includes a compressor that is operable to circulate a vapor compression refrigerant through the conduit between the indoor and outdoor units. The device is comprised of a support member containing a section of refrigerant line. The support member is located beneath the outdoor unit and the refrigerant line section is interposed in a portion of the refrigerant conduit between said compressor and said indoor unit, such that the refrigerant flowing between the indoor unit and the compressor is routed through the line section in the outdoor unit support member.

Abstract: A device is provided for dampening compressor-induced vibration in an air conditioning system of the type having an indoor unit, an outdoor unit and a refrigerant conduit therebetween. The outdoor unit includes a compressor that is operable to circulate a vapor compression refrigerant through the conduit between the indoor and outdoor units. The dampening device is comprised of plural vibration dampening elements spaced along the conduit, with the spacing between adjacent elements corresponding to the wavelength of a natural vibratory frequency of the conduit. The device is preferably located proximate to the compressor and inside of the outdoor unit cabinet in which the compressor is housed. Various embodiments of the dampening device are disclosed.

Abstract: An absorption pipe structure of a compressor, capable of reducing vibration of the absorption pipe and making the machinery room small-sized, by making short the length of the absorption pipe connected with the compressor and forming the curved part formed in a proper diameter, is provided.

Abstract: A refrigerator which has a pleasant front appearance by improving a structure to circulate air through a machine room thereof, and which restrains a transmission of operational noise from an interior to an outside of the machine room, thus performing a silent operation. The refrigerator has a cabinet defining a storage compartment therein, and a machine room defined at a top of the cabinet. The machine room is partitioned in an interior thereof into front and rear chambers by a noise buffering plate having a plurality of vent holes. A main inlet hole and a main outlet hole are provided side-by-side at an upper surface of the front chamber of the machine room so as to allow air to circulate through the machine room. A compressor, a condenser and a cooling fan are installed in the rear chamber of the machine room.

Abstract: A baffle for use in a refrigerator apparatus comprises a baffle plate comprising a first and a second opposing sides attached to an inner surface of the refrigerator apparatus, a baffle seal plate attached along a third side of the baffle plate, the baffle plate seal plate attached to the inner surface of the refrigerator apparatus.

Abstract: An air conditioner which includes a plurality of indoor units to cool air of a plurality of rooms. Included is a plurality of branch refrigerant lines that each include a backflow prevention part provided at an end of the branch refrigerant line and/or a pulsation dampening part provided at an end of the branch refrigerant line, adjacent to the main refrigerant line. The air conditioner acts to prevent a liquid part of the refrigerant from flowing in a reverse direction into idle indoor heat exchangers. Furthermore, because a pressure pulsation of the refrigerant is dampened by the pulsation dampening part before the refrigerant is supplied into the indoor heat exchangers, the air conditioner reduces vibration, and, thus, noise from the indoor heat exchangers which is caused by the pressure pulsation of the refrigerant.

Abstract: The present invention provides a method for masking noise in a motor vehicle that has a component that produces noise when operated. The method of the invention comprises monitoring the speed of the vehicle, and increasing the movement of the moveable part when the vehicle is at a predetermined speed. It is well known that vehicles naturally produce more noise as the speed of the vehicle is increased. The invention also provides a noise masking system that exploits the method of the invention.

Abstract: A compressor that sucks refrigerant gas from an external refrigerant circuit, compresses the sucked refrigerant gas and discharges the compressed refrigerant gas, comprising a cylinder having a plurality of bores, a front housing coupled to the front side of the cylinder and forming a crank chamber, a driving shaft supported so as to freely rotate with respect to the cylinder and the front housing, a single-headed piston connected to a slanting plate element mounted on the driving shaft and linearly reciprocating inside the bores of the cylinder, and a rear housing coupled to and closing the rear side of the cylinder.

Abstract: An improved piping structure of an air conditioner can minimize a vibration by change in a piping shape in looped pipings. In the piping structure, a first directional piping part configured on a same plane is changed to be slanted at a predetermined angle on one end thereof, to be displaced onto a third plane, and to be connected with a second directional piping part configured on a different plane from that of the first directional piping part. Further, the piping structure comprises a vertical piping part wound in an up and down direction and a horizontal piping part connected to the vertical piping part having one end changed at a predetermined slant angle.

Abstract: Silencing equipment is provided for an air-cooling assembly in a large off-road vehicle having wheels, traction motors for the wheels that operate in a motoring mode to propel the vehicle and a power generating dynamic braking mode, resistor grids for dissipating the dynamic braking power, and a blower for moving cooling air past the grids to cool them. The silencing equipment may include a resistor grid housing 24 and at least one upper inlet 22 for passing cooling air to the interior of the housing. The inlet includes noise-absorbing material. A conduit 28 is provided for directing cooling air from the upper inlet through a transition chamber to reach the blower and at least one resistor grid in the housing. The conduit is lined with noise-absorbing material. A removable cover 30 is provided for the conduit for accessing the air blower in the housing through the transition chamber, whereby servicing of the blower may be performed without removal of the entire upper inlet.

Abstract: A sonic nozzle is disclosed that is positioned between an evaporator and compressor in an air conditioning system. The sonic nozzle limits refrigerant flow rate to that allowed by sonic velocity at a throat area of the sonic nozzle. The sonic nozzle may have a by-pass flow area that allows for less pressure drop at lower flow rates where the by-pass flow area is sealed off at a predetermined pressure drop to force all flow through the sonic nozzle. Another embodiment that is disclosed features a thermally actuated suction throttling valve that is attached to a sonic nozzle. A power element of the throttling valve contains thermally active fluid, such as water, when frozen activates a piston member into the throat portion of the sonic nozzle to restrict fluid flow.

Abstract: In an air conditioner for a vehicle, when a target rotation speed of an electric compressor calculated by a target rotation speed calculating means is higher than an upper limit set by an upper limit setting means and a noise level is reduced from a level equal to or higher than a predetermined noise level to a level lower than the predetermined noise level, an inverter controls the compressor to stop for a predetermined period of time and subsequently increase rotation speed to the upper limit. Since the compressor is stopped for the predetermined period of time, the rotation speed of the compressor is controlled without detecting a rotational position of the compressor. Therefore, when the target rotation speed is higher than the upper limit and the noise level is decreased lower than the predetermined noise level, an actual rotation speed of the compressor is immediately decreased.

Abstract: Disclosed is a method for controlling noise reduction of an air conditioner comprising the steps of: (a) stopping a compressor, when the air conditioner is stopped under the condition that the compressor and an outdoor fan are operated; and (b) stopping the outdoor fan after a designated time after a point in time when the compressor is stopped in the step (a) elapses, thus reducing the size and duration of noise generated by the flow of the refrigerant due to a difference of inner pressures in the air conditioner and allowing the noise at a designated frequency band generated by the flow of the refrigerant, which causes unpleasantness to users, to be concealed by noise generated by the operation of the outdoor fan. Accordingly, the method of the present invention increases reliability of air conditioner products.

Abstract: Disclosed is a vibration absorbing apparatus for a compressor of a refrigerator. The vibration absorbing apparatus includes: an elastic member for absorbing a vibration generated during an operation of a compressor; a base pan supporting the elastic member; a stand installed in the base pan to prevent the elastic member from being bent; and a stopper installed in an upper portion of the stand to prevent the elastic member from being escaped from the base pan during a vibration of the compressor. The elastic member includes: a body having a plurality of grooves enclosing an interior surface and an exterior surface thereof, and a hollow axially passing through a central portion of the body; and a base being a lower portion of the body and being mounted on the base pan.

Abstract: The present invention relates to an elastic member and apparatus for a refrigerator compressor. A vibration absorption apparatus for a refrigerator compressor according to the present invention is connected to a foot of the compressor for transmitting the vibration generated when the compressor is operated, and includes an elastic member having a hollow passing through the central portion in an axial direction is formed; a base pan installed on a bottom of the refrigerator machinery room, for supporting the elastic member; a stand coupled with the base pan and passing through the hollow of the elastic member; and a stopper installed on the stand, for preventing the elastic member from being escaped from the base pan. The elastic member comprises a body having a plurality grooves enclosing an inner surface and outer surface thereof to have a vertical section in a zigzag; a projection of an upper portion of the body to which the stopper is forcedly attached; and a base being a lower portion of the body.

Abstract: A resistive muffler attenuates sound generated by the gas intake and suction valve during compressor operation of a refrigerant compressor. The resistive muffler is assembled inline with the suction gas flow of the compressor and is positioned within the compressor housing. The resistive muffler attenuates the sound generated by the compressor during its operation as refrigerant gas is drawn into the compressor from an evaporator and passes through the resistive muffler in transit to the suction valve and hence to the region of the compressor where the gas is physically compressed. The resistive muffler includes a muffler housing having an intake end and an exhaust end. An acoustic foam assembly is incorporated into the muffler housing.

Abstract: A compressor for compressing refrigerant in an air conditioning or refrigeration system, including a housing having a suction port, a discharge port, and a compression chamber, a mechanism for producing a compression cycle for compressing the refrigerant, wherein the compression cycle occurs in the suction port, discharge port and compression chamber, and a mechanism for providing liquid refrigerant into the compression cycle at a desired location for reducing pressure pulsations and associated radiated noise produced during the compression cycle.

Abstract: Two case members of the same shape are attached to the body of an expansion valve and a temperature sensing drive element through sound insulating members. Each of the two case members is formed having upper retaining and retainable portions at its upper part and lower retaining and retainable portions at its lower part. The upper retaining portion, upper retainable portion, lower retaining portion, and lower retainable portion of one of the case members are in engagement with the upper retainable portion, upper retaining portion, lower retainable portion, and lower retaining portion, respectively, of the other case member.

Abstract: A turbomachinery system for cooling a high power density device includes a turbomachine configured to deliver a high flux cooling medium toward the high power density device, a housing containing a motor, a compressor, or both, of the turbomachine, a heat exchanger in fluid communication with the turbomachine and arranged for being thermally coupled to the high power density device, and a transition duct arranged intermediate the heat exchanger and turbomachine.

Abstract: An apparatus for manipulating the air temperature within an interior compartment of a vehicle includes a compressor, a condenser, and an evaporator interconnected in a manner to remove heat from air in the interior compartment. A thermostatic expansion valve is connected between the condenser and evaporator, and includes an inlet and an outlet. A silencer screen is positioned at the outlet of the thermostatic expansion valve to reduce turbulence in refrigerant flow exiting the thermostatic expansion valve.

Abstract: In a compressor having a noise reducing apparatus capable of minimizing noise propagated to the outside of a casing, by constructing a bottom cap of a casing as a double wall structure and naturally filling oil inside the casing into the double wall, high frequency noise occurred at the bottom cap side can be efficiently excluded, and accordingly a noise absorption efficiency can be maximized.

Abstract: A noise abatement device and method to direct flow in a predetermined manner to substantially reduce the aerodynamic noise and structural vibrations produced by steam entering an air-cooled condenser in a power generating system. The interactive flow between the spargers that produces the aerodynamic noise and structural vibrations is largely eliminated by prohibiting fluid flow through selected flow regions within the spargers. The spargers include a stack of disks with fluid passageways. The fluid passageways are interrupted with continuous and undivided regions of the sparger to direct radial flow away from adjacent spargers, substantially eliminating the interactive flow.

Abstract: Twisted blades for outdoor air conditioner condensers and heat pumps that improve airflow efficiency to minimize operating power requirements. The blades can run at approximately 850 rpm to produce approximately 1930 cfm of air flow using approximately 110 Watts of power from an 8-pole motor with an improved diffuser assembly. Using an OEM 6-pole ⅛ hp motor produced approximately 2610 cfm with approximately 145 Watts of power while running the blades at approximately 1100 rpm. Power savings were approximately 24% (40 to 50 Watts) over the conventional configuration with increased air flow. Embodiments of two, three, four and five blades can be equally spaced apart from one another about hubs. Additionally, a novel noise reduction configuration can include asymmetrically mounted blades such as five blades asymmetrically mounted about the hub.

Abstract: A horizontal type compressor comprising: a differential pressure plate for dividing an inside of a casing into a high pressure chamber and a lower pressure chamber and thus maintaining an oil level of the high pressure chamber to be higher than that of the lower pressure chamber; and a lubricating unit for supplying oil stored in the high pressure chamber to each sliding part in the compressor and making the oil which finished a lubricating operation return to the high pressure chamber from the lower pressure chamber. The compressor smoothly supplies refrigerant oil and minimizes an amount of the refrigerant oil discharged outside the compressor, thereby prolonging a life of the compressor and increasing a reliability of the compressor. Also, the differential pressure plate and the muffler are integrally formed, thereby reducing a fabricating cost and reducing an assembling process.

Abstract: An apparatus for manipulating the air temperature within an interior compartment of a vehicle includes a compressor, a condenser, and an evaporator interconnected in a manner to remove heat from air in the interior compartment. A thermostatic expansion valve is connected between the condenser and evaporator, and includes an inlet and an outlet. A silencer screen is positioned at the outlet of the thermostatic expansion valve to reduce turbulence in refrigerant flow exiting the thermostatic expansion valve.

Abstract: Refrigerant compressed by a first stage compression elements (30) run by a motor (20) is discharged in the closed container (10) via a silencer chamber (35) to cool the motor (20) before the refrigerant is led to a second stage compression element (40). The refrigerant is discharged from the second stage compression element (40) out of the compressor after it is further compressed in the second compression element (40). Thus, the motor (20) is cooled in a simple cooling mechanism during normal operation of the compressor.

Abstract: Multi-type air conditioner including an outdoor unit having a compressor, an outdoor heat exchanger, a flow path control valve for controlling a flow path of the refrigerant from the compressor, and an outdoor unit piping system, a plurality of indoor units each having an indoor expansion device, an indoor heat exchanger, and an indoor piping system, a distributor for selectively distributing the refrigerant from the outdoor unit to the indoor units and returning to the outdoor unit again proper to respective operation modes, and noise preventing means on pipelines respectively connected to the indoor units to cut off refrigerant flow into inoperative indoor units when the air conditioner is in operation, for preventing occurrence of refrigerant flow noise at the inoperative indoor units.

Abstract: The suction muffler of a reciprocating compressor according to the disclosed invention comprises a flow controller for controlling the flow of refrigerant so that a steady amount of refrigerant flows into the suction port of the suction muffler. The flow controller comprises a fixing member having a main refrigerant path, a plurality of refrigerant sub-paths formed to vertically penetrate the fixing member along and adjacent to a circumference of the main refrigerant path at predetermined intervals, and a space with a diameter larger than an imaginary circle made by connecting the plurality of refrigerant sub-paths, formed under the main refrigerant path and the plurality of refrigerant sub-paths. A movable member has a first through hole formed to correspond to the main refrigerant path, and a plurality of second through holes formed at predetermined intervals on the imaginary circumference having a diameter larger than an imaginary circle made by connecting the plurality of refrigerant sub-paths.

Abstract: Disclosed is a method for controlling noise reduction of an air conditioner comprising the steps of: (a) stopping a compressor, when the air conditioner is stopped under the condition that the compressor and an outdoor fan are operated; and (b) stopping the outdoor fan after a designated time after a point in time when the compressor is stopped in the step (a) elapses, thus reducing the size and duration of noise generated by the flow of the refrigerant due to a difference of inner pressures in the air conditioner and allowing the noise at a designated frequency band generated by the flow of the refrigerant, which causes unpleasantness to users, to be concealed by noise generated by the operation of the outdoor fan. Accordingly, the method of the present invention increases reliability of air conditioner products.

Abstract: A compressor that inhales refrigerant gas from an external refrigerant circuit, compresses the inhaled refrigerant gas and discharges the compressed refrigerant gas, comprising a cylinder block having a plurality of bores, and a suction muffler chamber having a suction port connected to an external refrigerant circuit installed on the outer circumferential surface of the cylinder block, a front housing coupled to the front side of the cylinder block and forming a crank chamber, a driving shaft supported so as to freely rotate with respect to the cylinder block and the front housing, a single-headed piston connected to a slanting plate element mounted on the driving shaft and linearly reciprocating inside the bores of the cylinder block, and a rear housing connected to and closing the rear side of the cylinder block, having a discharge chamber and a suction chamber, and having two or more suction chamber connecting passages at an upstream side of the suction chamber.

Abstract: A compressor that sucks refrigerant gas from an external refrigerant circuit, compresses the sucked refrigerant gas and discharges the compressed refrigerant gas, comprising a cylinder having a plurality of bores, a front housing coupled to the front side of the cylinder and forming a crank chamber, a driving shaft supported so as to freely rotate with respect to the cylinder and the front housing, a single-headed piston connected to a slanting plate element mounted on the driving shaft and linearly reciprocating inside the bores of the cylinder, and a rear housing coupled to and closing the rear side of the cylinder.

Abstract: In order to provide a screw compressor comprising two screw rotors which are disposed in screw rotor bores in a compressor casing and which compress a refrigerant entering at a refrigerant inlet and discharge it at a refrigerant outlet, and comprising an inlet provided in the compressor casing for refrigerant which is coming from a supercooling circuit and is passed to the inlet in a system of lines, the inlet being disposed in such a way that it opens out into compression spaces enclosed by the screw rotors and screw rotor bores, in which compressor the pressure oscillations or pulsations occurring at the inlet propagate as little as possible to the pipeline system of the supercooling circuit outside the compressor casing, it is proposed that the inlet is preceded by a damper channel which is associated with the system of lines and in which refrigerant from the supercooling circuit is present.

Abstract: A closed motor-driven compressor includes a compression component (2) and an electric component (3) for driving the compression component (2), both of which are elastically supported within a closed vessel (1). A suction muffler (8) is mounted on the compression component (2) and includes a plurality of elements (10, 11, 12; 14, 15, 16; 18, 19, 20; 22, 23, 24; 26, 27, 28) assembled together and each made of synthetic resin. One of the plurality of elements (10, 11, 12; 14, 15, 16; 18, 19, 20; 22, 23, 24; 26, 27, 28) has a guide rib (13; 17; 21) integrally formed therewith that is tapered down toward an adjoining one of the plurality of elements (10, 11, 12; 14, 15, 16; 18, 19, 20; 22, 23, 24; 26, 27, 28), thereby facilitating assembly of the two elements.

Abstract: An air handling apparatus for blending outside and return airflow including a housing having exterior side walls, a top and a bottom and containing first and second inlet regions and a mixing chamber. Outside air flows through a first inlet into the first inlet region while return air flows through another inlet into the second inlet region. There are also first and second damper mechanisms positioned between the first and second inlet regions and the mixing chamber, each capable of adjusting the amount of airflow from the respective inlet region to the mixing chamber. An exhaust fan is mounted on the housing above the second inlet region while an air supply fan is mounted in the housing on the downstream side of the mixing chamber. Heating and cooling coil units can be located downstream of the mixing chamber.

Abstract: The entire discharge flow in a high side, vertical, hermetic rotary compressor is directed into the oil sump which generates foam for sound attenuation and heats the oil to reduce its viscosity and to drive off refrigerant dissolved in the oil.

Abstract: An air conditioner has an evaporator, a main compressor, a condenser, and an energy recovery device. The condenser receives a compressed refrigerant from the compressor and condenses the refrigerant to either a liquid phase or a saturated liquid-vapor phase. The condensed refrigerant is passed through the energy recovery device to expand the refrigerant. The refrigerant passing through the energy recovery device is regulated to maintain the refrigerant in a high cavitation region within a motor, while maintaining within a predetermined refrigerant pressure range in the motor. During refrigerant regulation, sounds and vibrations are created that may be unpleasant to humans. A sound suppression device is included in the air conditioner to reduce or eliminate these sounds, and is positioned between the condenser and the energy recovery device.

Abstract: The gas flow direction and the noise generation direction are in opposite directions in the suction muffler. The flow path in the muffler has a number of changes in direction and the flow path cross section decreases at each change of direction in the direction of flow.

Abstract: A device for muffing the sound of water droplets falling onto an upper surface of the housing of an air conditioning unit that extends beyond the side of a building is disclosed. The muffling device comprises a plurality of screens of different fineness of mesh, and a frame for holding the plurality of screens arranged in a progressively finer parallel spaced-apart relationship. The device is secured to the housing of the air conditioning unit with the finest mesh screen closest to and in parallel relation with the upper surface of the housing.

Abstract: Sound attenuation apparatus for use in a bus in which an air conditioning unit that is mounted on the rear wall of the bus is arranged to exchange conditioned air for return air drawn from the buses passenger compartment through a central opening in the rear wall of the bus. A housing is mounted over the central opening inside the bus that has a front wall that extends to either side of the opening. Apertures are mounted in both the extended sections of the front wall that forces the return air passing through the housing to move over a tortuous path of travel thereby attenuating the sound in the air flow path. The interior surfaces of the housing are covered with an open cell foam material which further absorbs the sound in the air flow path.

Abstract: A sound suppression system for suppressing the noise of an engine within an enclosure of an outdoor unit for a transport refrigeration system. A resonator is provided to suppress noise caused by the inflow of air to the air intake manifold of the engine, and a sound panel is provided in the bottom wall of the enclosure to suppress noise emanating from the engine. The resonator and the sound panel are co-located in the same plane and are preferably integrally formed of a molded plastic material.

Abstract: A compressor for compressing refrigerant in an air conditioning or refrigeration system, including a housing having a suction port, a discharge port, and a compression chamber, a mechanism for producing a compression cycle for compressing the refrigerant, wherein the compression cycle occurs in the suction port, discharge port and compression chamber, and a mechanism for providing liquid refrigerant into the compression cycle at a desired location for reducing pressure pulsations and associated radiated noise produced during the compression cycle.

Abstract: A refrigeration system which can reduce the amount of moisture permeating into the system, inexpensively and by a simple structure, is disclosed. Rubber hoses (7, 8) capable of absorbing vibrations are arranged on the discharge and the intake sides of a compressor (1). It was found that the amount of moisture in the system can be effectively reduced by reducing the amount of moisture permeating the rubber hose on the discharge side. A freezing limit line is set for defining to a predetermined level the amount of moisture in the system determined by the amount of the refrigerant sealed in the system, the amount of the lubricating oil sealed in the system, the amount of moisture permeation of the hoses (7, 8) and the number of the years elapsed after operation start. The hose (7) on the discharge side of the compressor has a smaller amount of moisture permeation than the hose (8) on the intake side.

Abstract: An air treatment system having an outer heat exchange coil, an inner heat exchange coil spaced-apart from and encompassed by the outer heat exchange coil, seal structure positioned with respect to both coils so that air pulled through the air treatment system by air movement apparatus may flow through the inner heat exchange coil without flowing through the outer heat exchange coil; and in one aspect, an air treatment system having an outer heat exchange coil; an inner heat exchange coil within the outer heat exchange coil; the inner coil spaced-apart from the outer heat exchange coil; the inner heat exchange coil and the outer heat exchange coil defining an inner chamber therebetween; the inner chamber positioned so that air exhaust apparatus above the inner heat exchange coil moves air into the inner chamber for exhausting therefrom by the air exhaust apparatus; air flowing from outside the outer heat exchange coil, through the outer heat exchange coil, and into the inner chamber; and air flowing from outsi

Abstract: A fluid compressor includes a compressor inlet for receiving a medium, a compressor for compressing the medium, a compressor outlet for discharging the compressed medium and a compressor muffler. The compressor muffler includes a housing defining an inner space, an inlet for receiving a compressed medium, a muffling structure located in the inner space, wherein the muffling structure has a plurality of chambers for receiving the compressed medium from the inlet, an outlet for discharging the compressed medium and a flow path located in the inner space; The flow path communicates the inlet with the muffling structure and the muffling structure with the outlet; A method for reducing any noise-generating frequencies present in a compressed medium is additionally presented.

Abstract: A grill for an air conditioning unit has one or more grill members wrapped with wire so as to present a varying topographical surface to the flow of air over the grill members. The resulting grill member profile that is presented to the air flow reduces vortex shedding noise that would otherwise occur without the wire wrapping. Various wire wrappings are disclosed which produce the desired effect of reducing the vortex shedding noise.

Abstract: The tunable resonator is coupled to the engine speed control such that the resonator is set to a different frequency range when the engine speed is changed. The frequency range is, changed to a higher frequency by closing a valve which effectively reduces the length of the resonator.

Abstract: Suction muffler for a compressor including an inlet for introducing a refrigerant into the suction muffler, a chamber for temporary storage of the refrigerant and dropping a pressure of the refrigerant by means of a sudden increase of a volume of the refrigerant, a resonator for attenuating a noise of a specific frequency, a refrigerant supply tube for leading the refrigerant from the chamber to a cylinder, thereby stopping transmission of a pulsating flow occurred by the piston movement in the cylinder to outside of the refrigerant supply tube and preventing transmission of a noise from a suction valve and a discharge valve to outside of the suction muffler, wherein the chamber includes a vibration member having a vibration frequency corresponding to a pulsation frequency occurred at the refrigerant supply tube, thereby increasing supply of refrigerant to the cylinder a improving a performance of the compressor.

Abstract: A valve body 30 of an expansion valve 10′ is equipped with a first passage 32′ formed by a cutting process through which a high-pressure refrigerant travels, and on the lower portion of the valve body 30 is formed a space 35a defining a valve chamber 35′ from the bottom portion of the valve body 30 along the axial direction by a passage 33. The passage 33 defining the space 35a and the first passage 32′ are formed so as to interfere with each other, and at the interference area is formed a throttle portion 323. That is, the diameter of the first passage 32′ is formed so that the cross-sectional area thereof is gradually reduced toward the direction of the valve chamber 35, and a throttle portion 323 is formed to the area of the first passage 32′ interfering with the passage 33 defining the valve chamber 35′. The throttle portion 323 is formed to have a cross-sectional area corresponding to a diameter of approximately 3 mm.