Abstract: An active noise control system for a three-dimensional space, including noise detecting means, sound generating means, noise control effect detecting means and a control device consisting of a phase of a wave signal fed from the noise detecting means wherein a plurality of noise control effect detecting means and sound generating means are disposed at a distance shorter than a wavelength of the noise to be controlled, and input signals of the respective sound generating means and output signals of the respective noise control effect detecting means are fed through filters, separately, to control the sound for active noise control. In case of an air conditioner, the noise control effect detecting means are disposed at positions where an air stream flowing through the air conditioner is not obstructed thereby.

Abstract: A refrigeration compressor incorporating an improved suction muffler is disclosed. The suction muffler provides dual sound attenuating chambers within a single housing, which housing is secured to the suction inlet conduit extending between the motor cover and suction inlet for the compressor. The suction inlet conduit is increased in diameter between the motor cover and the compressor inlet to provide a stepped portion which operates to reflect pressure waves. Integrally formed openings in the sidewall of the conduit provide communication with each of the two chambers and the respective chambers may be tuned to attenuate different specific frequencies. Internal integrally formed baffles within each of the chambers serve to reduce standing waves within the chambers as well as adding stiffness to the muffler.

Abstract: A hermetic compressor including a vibration damper situated around the outside of the compressor housing. The vibration damper is constructed from a length of wire wrapped around the housing to form a plurality of windings each winding in contact simultaneously with an adjacent one and the housing. The wire is wrapped about portions of the housing having the highest acceleration and vibration production potential. Alternatively, the windings may be formed of separate wires connected to a bracket and, further, more than one layer of windings of the equal or different diameters is possible.

Abstract: The present invention discloses an integral air-conditioner of which an indoor portion and an outdoor portion are connected elastically, the air-conditioner includes an indoor portion (1), an outdoor portion (3), and a means for elastically connecting the indoor portion and outdoor portion integrally. The integral air-conditioner according to the present invention retains all the advantages exhibited by the window air-conditioner and the divided air-conditioner in the prior art, meanwhile overcomes their drawbacks. The integral air-conditioner according to the present invention can be easily mounted and maintained, and has a lower noise intensity which is only 1/2 of that of the window air-conditioner in the prior art. The air-conditioner according to the present invention is an ideal air-conditioning apparatus.

Abstract: An electric expansion valve is arranged between a first indoor heat exchanger and a second indoor heat exchanger. At a time of cooling operation, the electric expansion valve is fully opened to connect both the indoor heat exchangers to each other. At a time of dehumidifying operation the electric expansion valve is narrowed to apply a pressure reducing action across these indoor heat exchangers so that the first indoor heat exchanger acts as a reheater and the second indoor heat exchanger as an evaporator. The indoor air is cooled and dehumidified by the second heat exchanger and then reheated by the first indoor heat exchanger and blown into the room. At a time of dehumidifying operation, the temperature of the air blown into the room varies by controlling the speed of an outdoor fan.

Abstract: A sound attenuating enclosure with sound absorbing panels. The panels are positioned in an array of four side panels and a top panel. The array of panels is covered with vinyl material forming seams between adjoining panels and flaps for securing the panels together to form the enclosure. Each of the panels is provided with a pouch having a resealable opening for containing a flat sound reflecting element. One predetermined side panel is provided with apertures for allowing supply lines to pass through the enclosure.

Abstract: A silencer attenuating a noise from a noise source to be ventilated of this invention comprises a machine compartment with a one-dimensional duct configuration whose sectional dimension is sufficiently small in comparison with the wavelength of the noise to be attenuated, a compressor and/or other machinery disposed within the machine compartment, an opening for dissipation of heat as disposed in a wall of the machine compartment and opening in a direction generally perpendicular to the direction of advance of sound within the machine compartment, a vibration pickup for detecting the vibration of the machinery corresponding to the output noise of the machinery, and a control circuit for processing output signals from the vibration pickup to drive a sound generator such as a speaker. The sound generator outputs a controlling signal dependent on the machine noise to cancel the noise about to emerge from the machine compartment.

Abstract: A muffler tube for use in a hermetically sealed compressor is disclosed. The muffler tube of the present invention has a roughened outer finish, and has a protuberance extending radially outwardly therefrom, which protuberance is received in a recess in the inner wall of the muffler. The combination of the roughened outer finish and the protuberance connection assist in preventing the muffler from turning on the tube, and from moving vertically on the tube.

Abstract: A muffler and an oil separator located within a common shell. The muffler includes a plurality of chambers tuned to different frequencies. The flow path is serially through the muffler into contact with an agglomerating pad followed by flow through demister pads and a coalescer.

Abstract: An air conditioning apparatus having a condenser fan, an evaporator fan, a compressor, at least two motor for driving the fans and the compressor, and being responsive to vibration of the apparatus to control the speed of each motor to reduce the vibration. In its preferred embodiments, the apparatus performs a test to determine optimum speeds of the motors to minimize the vibration. The apparatus uses a microcomputer, operative during the test to change the speed of at least one of the motors to each of a plurality of different speed values within a predetermined speed range, and at least one vibration detector. The detector detects values of the vibration when the motors are operating at the different speed values. At the end of the test, the motors are controlled to operate at the speed value at which the vibration is minimized.

Abstract: A muffler tube for use in a hermetically sealed compressor is disclosed. The muffler tube of the present invention has a roughened outer finish, and has a protuberance extending radially outwardly therefrom, which protuberance is received in a recess in the inner wall of the muffler. The combination of the roughened outer finish and the protuberance connection assist in preventing the muffler from turning on the tube, and from moving vertically on the tube.

Abstract: There is disclosed an improved two-piece enclosure for a refrigerant compressor which is very simple in design and which effectively attenuates the sound produced by that compressor and, at the same time, requires a minimum amount of additional space and provides easy access to the compressor for service and the like. Two embodiments are shown, one with sound insulation on the walls of the container and another with sound insulation on the compressor.

Abstract: In a low noise refrigerator, a rotary compressor constituting a noise source is arranged within a machine chamber provided with an opening in one location, which chamber has a one-dimensional duct construction having a cross-sectional dimension which is small relative to trhe wavelength of the noise which is to be reduced. A vibration pick-up being located in the vicinity of the rotary compressor. The vibration pick-up detects compressor vibrations which correlate to the compressor noise, in the tangential direction of the compressor. There is provided a control circuit that processes the output signal of the vibration pick-up. In the machine chamber, a sound generator is driven by the output signal of the control circuit to generate a control sound, so that the compressor noise which tries to issue from the opening is canceled by the control sound.

Abstract: A refrigerator with a noise attenuating function includes a cabinet having storage and machine compartments, a compressor disposed in the machine compartment, a noise detector disposed in the machine compartment for detecting noise produced from driving of the compressor and converting the noise to an electrical signal, an operational unit for converting the electrical signal to an acoustic signal for an active noise control, a cancellation sound producer producing a sound of opposite phase with the noise based on the acoustic signal so that the noise is attenuated, a noise attenuation monitoring sound receiver for monitoring the noise attenuating effect of the cancellation sound producer, an adaptive control circuit changing an operational factor of the operational unit by a predetermined amount when the monitoring result of the noise attenuation monitoring sound receiver is out of a predetermined tolerance, the adaptive control circuit being adapted to continuously perform the operation of changing the oper

Abstract: In a low noise refrigerator, a compressor constituting a noise source is arranged within a machine chamber provided with an opening in one location, which chamber has a one-dimensional duct construction in which its cross-sectional dimension is small relative to the wavelength of the noise which is to be reduced. A vibration pick-up is located in the vicinity of the compressor. The vibration pick-up detects compressor vibrations which correlate to the compressor noise of the compressor. There is provided a control circuit that processes the output signal of the vibration pick-up. In the machine chamber, a sound generator is driven by the output signal of the control circuit to generate a control sound, so that the compressor noise which tries to issue from the opening is canceled by the control sound.

Abstract: Radiant sound reduction is achieved in a variable speed compressor by bleeding a small amount of refrigerant into the oil sump for froth production. The refrigerant is bleed from the discharge of the compressor through a solenoid controlled valve which is opened to permit a bleed flow when the compressor is operating at or above a predetermined capacity/speed. This limits system efficiency losses and produces sound reduction only when it is needed.

Abstract: A compression-type air-conditioning system for a railraod car, intended in particular for a high-speed train, includes a refrigerant compressor, a condenser with tubes in which compressed fluid is cooled by circulation of air around the tubes and is thereafter liquified, an expansion valve supplying a low-temperature refrigerating gas, and an evaporator following the expansion valve. The tubes of the condenser form an oblique bank between a floor of the railroad car and an underframe of the air-conditioning system. The oblique bank enables, on the one hand, the number of the tubes and consequently the cooling capacity of the air-conditioning system to be increased. On the other hand, space is freed up in a vertical direction for fitting damping devices at different fastening points on the condenser. As a result of the invention, there is an improvement in the comfort of passengers, both in terms of air-conditioning and in terms of reducing vibrations. Furthermore, there is a reduction in operating costs.

Abstract: An audible sound radiated from an air conditioning apparatus is decreased when the actual audible sound detected by the sound sensor is greater than a predetermined audible sound value which is modified according to changes in the ambient light or the ambient temperature.

Abstract: In a low side hermetic compressor, a small portion of the compressed refrigerant gas is diverted and discharged into the oil sump through an orifice into the upper level of the oil in the sump. This results in a supersaturated solution of refrigerant in oil in the upper level which drives the refrigerant out of the oil, thereby creating froth which provides sound reduction without disturbing the lower level which remains stratified.

Abstract: An air conditioner generally comprises a compressor accommodated in the outer casing thereof and the compressor is surrounded by a sound-proof cover. The sound-proof cover is formed of a main body made of a sound absorbing material and a heat insulating member preferably made of a foam of a thermosetting resin which is bonded to the surface of the main body opposing to the outer surface of the compressor. The heat insulating member has a heat transfer efficiency smaller than that of the main body. The main body is preferably formed of a sound absorbing member and a noise insulating member. The heat insulating member, the sound absorbing member and the noise insulating member are laminated and bonded to each other in this order. The entire sound-proof cover is arranged in contact with substantially the entire outer periphery of the compressor. An outer casing formed of a sound absorbing material may be further disposed so as to surround the sound-proof cover with space therebetween.

Abstract: A transport refrigeration unit having a top and bottom, a back, and side planes which include a front and first and second sides. The transport refrigeration unit further includes a condenser having air intake openings along a selected side plane of the unit, with condenser air being discharged through the top. A sound reducing cover is disposed to surround the transport refrigeration unit. The sound reducing cover is lined with a sound absorbing material, and it re-positions the condenser air intake such that incoming condenser air enters the unit through the top, instead of through a side plane, while maintaining top air discharge. In one embodiment the sound reducing cover separates incoming and exiting air in a direction from the front to the back of the unit, and in another embodiment in a direction from one side of the unit to the other side.

Abstract: A cooling unit suitable for use in an automobile air conditioning system. The cooling unit includes an evaporator disposed in a casing having air inlet and air outlet openings to permit air passage through the evaporator. A vibration absorbing mechanism comprising an elastic material surrounds a peripheral surface of the evaporator and is disposed between the evaporator and the casing to prevent the transfer of vibration from the evaporator to the casing. Accordingly, the vibration absorption mechanism reduces or eliminates noise related to evaporator vibration from reaching the automotive passenger compartment.

Abstract: In a low side hermetic compressor, a small portion of the compressed refrigerant gas is diverted and discharged into the oil sump through an orifice into the upper level of the oil in the sump. This results in a supersaturated solution of refrigerant in oil in the upper level which drives the refrigerant out of the oil, thereby creating froth which provides sound reduction without disturbing the lower level which remains stratified.

Abstract: In a low side hermetic compressor, a small portion of the compressed refrigerant gas is diverted and discharged into the oil sump through an orifice into the upper level of the oil in the sump. This results in a supersaturated solution of refrigerant in oil in the upper level which drives the refrigerant out of the oil, thereby creating froth which provides sound reduction without disturbing the lower level which remains stratified. A check valve is provided for preventing reverse flow while requiring a predetermined pressure differential for diversion.

Abstract: A heat pump system comprised of an internal combustion engine and a rigidly connected refrigeration compressor is provided with a vibration isolation support having compression springs which have spring rates and natural vibration frequencies that are substantially less than the lowest operating frequency of the internal combustion engine/refrigeration compressor combination.

Abstract: A cold finger portion of a refrigerator is coupled to a movable member by means of a spring member having a linear characteristics to form a vibration system make phase difference between pressure variation and movement of the movable member and amplitude thereof possible to set at optimum values and to make a center of movement of the movable member constant by the linearity of the spring member regardless of operating condition.

Abstract: In cryogenic refrigerator provided with a cryostat having a low temperature level maintaining part for cooling and maintaining a part to be cooled at a very low temperature level and an expander which is fitted in the low temperature level maintaining part of the cryostat and generates cold in the low temperature level maintaining part by expanding refrigerant gas compressed by a compressor, vibration of the working expander is prevented from being transmitted to the part to be cooled by fixing and supporting the part to be cooled to the cryostat, separately from the expander, thereby minimizing the bad influence or vibration on a cryogenic working apparatus which is sensitive to vibration and by integrally supporting the part to be cooled and the expander to the crystat. In this way, the necessity of supporting the part to be cooled and the expander individually is eliminated and installation of the refrigerator is easy.

Abstract: A hermetically sealed scotch yoke compressor assembly is disclosed wherein a crankcase includes annular channels formed on the top and bottom surfaces thereof defining muffling chambers. Gas refrigerant compressed within radially disposed cylinders into cylinder head covers is channeled into the upper annular muffler chamber and them through passages extending through the crankcase into the lower muffling chamber. An annular cover plate for covering the bottom annular channel is attached to the crankcase at its radially inner extreme and is biased against the crankcase at its radially outer extreme. Spacers between the cover plate and the crankcase provide an annular discharge opening directing discharge gas onto the motor windings.

Abstract: A refrigeration system comprising in closed series-flow relationship, a condenser, a capillary tube flow restrictor, and an evaporator including means connecting the outlet end of the restrictor to the evaporator inlet for reducing the noise generated by refrigerant flowing from the restrictor.

Abstract: A hermetic reciprocating piston refrigeration compressor utilizes separate cylinder head members for the discharge and suction plenum chambers adjacent the discharge and suction valves. The two cylinder heads extend over substantially the entire area of the valve plate at the end of the cylinder carrying the valves. A discharge cylinder head is formed of metal while the suction cylinder head is formed of a plastic material of low thermal conductivity to minimize heat transfer between the discharge and suction plenums. The suction cylinder head is formed as a unitary member to include also passages and a portion of the suction muffler and is secured in place by a single fastening member.

Abstract: In a rotary compressor for refrigeration and heat pump systems with an integrated drive motor on the high-pressure side, the operating medium will flow over the drive motor. During operating of the rotary compressor gas pulsations/pressure pulses will occur on both low-pressure and high-pressure sides. In order to suppress these pressure pulses on the high-pressure side one or more chambers with different volumes are provided, joined by channels between the discharge opening and the drive motor.

Abstract: A new and improved surge tank for the refrigeration circuit of an automobile air-conditioning system is fabricated from tube stock and comprises a unitary main cylindrical body having a sidewall and end walls. The end walls are formed by friction spinning.

Abstract: A unitary air conditioner including a compressor, a chiller coil, a condenser, an indoor fan and an outdoor fan provided on a common base. An outdoor cabinet accommodates the compressor, condenser and outdoor fan. An indoor cabinet accommodates the chiller coil and the indoor fan. The outdoor cabinet has a first noise shielding member facing the indoor cabinet for shielding the noise produced in the outdoor cabinet. The indoor cabinet has a second noise shielding member facing the first noise shielding member for preventing propagation of the noise into the indoor cabinet. The first and second noise shielding members are spaced apart from each other to separate the outdoor and indoor cabinets, which are mounted on the base.

Abstract: A muffler for motor compressors comprising a body closed at the lower side by a cover and provided on its frontal wall with a hole through which the refrigerating gas is sucked. The gas introduced into the interior of the body strikes against the rear wall of the body and is diverted toward two narrow passages formed by the lateral internal walls of the body and by vertical walls of an M-shaped element located internally of the body. The inclined walls of the element favor the collection of the oil which has separated from the refrigerating gas and directs it toward an inclined plane which facilitates the discharge of the oil, by gravity, through a groove made in the body of the muffler.

Abstract: A thermal energy detecting system includes a closed cycle cooler (refrigerator) having a piston assembly including a piston, a piston housing and a preloaded spring mounted in the piston housing between the head of the piston and the piston housing for substantially reducing any bearing clearances of the piston assembly during the pressure changes occurring above and below the piston during the cooling cycle of the cooler.

Abstract: The suction gas supply tubes are made integral with the seal for sealing the gap between the cylinder head and the cylinder block caused by the valve assembly. The suction gas supply tubes have flared inlets and a long, narrow tapering cross section to minimize flow loses. Additionally, the length of the tubes is such that they provide pressure pulse attenuation and tuning.

Abstract: A refrigeration compressor is provided with a combined sound dampening and centrifugal liquid separator chamber.

Abstract: A muffler on the intake tube in a hermetically sealed compressor for refrigerating apparatuses in direct communication with the intake chamber located in the compressor cylinder head. The body of the muffler, preferably made of plastic material, consists of two half-shells of identical form and structure assembled in an overlapped way and turned by 180.degree. C. with respect to each other.

Abstract: A muffler for hermetically sealed compressors consisting of a body made of plastic material with two chambers separated by a wall and directly assembled on the compressor cylinder head by means of two lined up small tubes equipped with special sealing means. The danger that the muffler may break loose from the head and possibly rotate on its axis of vertical symmetry is thus avoided.

Abstract: A noise suppressing feeder tube for use in a refrigeration circuit is disclosed. A single unitary member having a middle portion flattened to reduce this cross-sectional diameter is disclosed for connecting a capillary tube to the evaporator of a small refrigeration circuit. By forming a unitary piece with a reduced cross-sectional area it has been found that refrigerant noise as is caused during the turbulent flow from the capillary tube to the evaporator may be suppressed.

Abstract: There is provided a heating apparatus having a heat pump including a compressor, a condenser, and an evaporator arranged in a closed circuit. A heat storage medium is contained in a storage vessel, the condenser or the evaporator being positioned therewithin. A sealed housing is disposed within the storage vessel, the compressor being positioned within the housing and rigidly connected thereto. The condenser or the evaporator is rigidly mounted to the exterior of said housing, the housing and the compressor and the condenser or the evaporator thereby forming a rigid unit. This rigid unit is resiliently mounted in the storage vessel to enable the same to be vibrated in the heat storage medium.

Abstract: A hermetic reciprocating piston refrigeration compressor has a high efficiency muffler system. The suction muffler has an inlet adjacent the refrigerant return line and is made of an insulating material. It is mounted on a pair of suction tubes secured to the cylinder head and extending into the interior of the muffler. A discharge muffler system includes a pair of large muffler chambers formed partially in a cylinder block and connected by an external transfer tube. A large straight passage connects the discharge plenum in the cylinder head with one muffler chamber, while a discharge line extends from the other muffler chamber to the exterior of the compressor casing.

Abstract: A suspension system for a motor compressor unit mounted within a hermetically sealed shell. The shell defines at least one chamber filled with refrigerant suction gas and a second chamber filled with refrigerant discharge gas. The compressor's cylinder block includes a wall member extending into contact with the interior surface of the shell to support the unit in a vertical plane taken through the shell.

Abstract: A motor compressor unit comprising a compressor, a motor, a shell enclosing the compressor and the motor, a motor cap located within the shell, covering a portion of the motor, and defining an attenuation tube opening, and an attenuation tube connected to the motor cap and extending through the attenuation tube opening. The attenuation tube includes a body; first and second lower lips extending outward from the body, below and in pressure contact with an outside surface of the motor cap, first and second alignment flange portions projecting above the first and second lower lips, adjacent opposed surfaces of the motor cap defining the attenuation tube opening; said first and second upper lips extending outward from the body, above and in pressure contact with an inside surface of the motor cap.

Abstract: A hermetically sealed motor-compressor unit for refrigerators, of vertical axis, comprising a container for said motor compressor unit defining a sump for the gravitational collection of oil therein and a motor compressor unit positioned within said container, said compressor unit comprising a casing defining a plate, a cylinder, silencer portions positioned at the end of said cylinder below said plate, upper support means extending upwardly from said plate, perimetral walls extending upwardly along a portion of the plate and lower support means extending downwardly from the plate supporting said motor compressor in said container; an electric motor supported on said upper support means; spherical caps fastened to said silencer portions to form silencers; a cylinder head defining a suction chamber and delivery chamber interconnected to said silencers; a vertical shaft and a lubricating member disposed on the lower end of said shaft and immersed in said sump.

Abstract: A hermetic compressor housing formed from sheet metal as two housing halves which when joined form a generally ellipsoidal inner surface having a maximum radius of curvature of about one order of magnitude greater than the minimum radius of curvature and deviating from the generally ellipsoidal shape only where necessary for supporting a compressor-motor assembly therein and for joining the housing halves is disclosed and provides a housing of relatively uniform rigidity to reduce the level of sounds radiated thereby. In one specific embodiment all of the audible natural resonant frequencies of the housing are above 3500 Hz.

Abstract: When a fluid is jetted from an orifice having a small diameter into an ample space having a much greater cross-sectional area than the orifice, as in the case of a refrigerant jetted from a restriction or orifice into a refrigerant pipe of a refrigeration system, jet noise of high frequency is generated in the region around the orifice. In order to suppress the generation of this jet noise, the present invention provides a silencer which includes a casing, an orifice of a small diameter arranged in the casing for jetting a refrigerant into the casing and an obstruction disposed in the casing at a position within a distance which is 5 times as large as the diameter of the orifice. The obstruction can have various forms such as bar-like form, disc-like form and so forth and can be made from various materials such as rubbers, plastics and metals. The obstruction disposed at such a position cause a change of pattern of the fluid flow to effectively suppress the generation of noise.

Abstract: A muffler for attenuating the sound of the hot refrigerant gas discharged from a hermetic refrigeration compressor and for transferring heat from the hot discharged refrigerant gas to a water tube arranged in heat exchange relationship with the muffler. The water tube is adapted to be connected to a water heater tank in a manner that recirculates water from the tank through the water tube in a closed circuit.

Abstract: A hermetic refrigeration compressor includes a suction muffler formed from two pieces of plastic material mounted on the cylinder housing. One piece is cylindrical in shape with an end wall having an aperture for receiving a suction tube connected to the cylinder head. The other piece fits over and covers the other end of the cylindrical piece, and includes a flaring entrance horn which extends toward the return line on the sidewall of the compressor shell.

Abstract: A hermetic reciprocating piston refrigeration compressor utilizes separate cylinder head members for the discharge and suction plenum chambers adjacent the discharge and suction valves. The two cylinders heads extend over substantially the entire area of the valve plate at the end of the cylinder carrying the valves. A discharge cylinder head is formed of metal while the suction cylinder head is formed of a plastic material of low thermal conductivity to minimize heat transfer between the discharge and suction plenums. The suction cylinder head is formed as a unitary member to include also passages and a portion of the suction muffler and is secured in place by a single fastening member.