A rotary compressor includes: a shell defining an internal space; a driving motor arranged in the internal space of the shell; and a compression mechanism unit to receive power of the driving motor and compress refrigerant, wherein the compression mechanism unit includes: a cylinder defining a chamber in which the refrigerant is compressed; a rotary shaft connected to the driving motor; a roller located in the chamber and connected to the rotary shaft to compress the refrigerant in the chamber while being rotated; a bearing coupled to the cylinder and having a discharge port through which the refrigerant compressed in the chamber passes; a muffler coupled to the bearing and into which the refrigerant passing through the discharge port is introduced; and a noise reducing unit fixed to the muffler to define a noise reducing chamber together with the muffler.

A compressor unit (10) of a refrigerating machine (100) for domestic or commercial use has a rotary compressor (11) which has a BLDC or BLAC motor (13), connected to a compression element (12) for actuating it, and a control device (16) connected to the motor (13), for driving it at a variable speed. The compressor (11) further has a a housing (17) which encloses the motor (13) and the compression element (16) and which has a side wall (20) inside of which the stator (14) of the motor (13) is fixed. The compressor unit (10) also comprises an operating shell (21) covering the housing (17) and in thermal communication with the side wall (20). The operating shell (21) dissipates heat transmitted to it by the housing (17) and contrasts or absorbs or dissipate sound waves having a frequency of between 4 kHz and 16 kHz.

A motor oil pump assembly includes: an inner sound insulation enclosure encloses an oil pump component, and the inner sound insulation enclosure and the oil pump component define an inner sound insulation cavity filled with low-pressure oil, the inner sound insulation cavity is in communication with a low-pressure cavity of the oil pump component, and the inner sound insulation enclosure is provided with a sound insulation enclosure cavity; and a pre-tightening buffering component, where the pre-tightening buffering component includes a piston and an elastic member, the piston fits in with the sound insulation enclosure cavity, the piston and an upper end cover of the oil pump component are integrally formed, and the elastic member is elastically sandwiched between a top wall of the sound insulation enclosure cavity and the piston, where the sound insulation enclosure cavity is in communication with a high-pressure cavity of the oil pump component.

A vacuum pumping system includes a vacuum pump and a soundproofing arrangement. The vacuum pump is accommodated in a pump housing. The soundproofing hood surrounds the pump housing and includes a hood air inlet and a hood air outlet. To improve dampening of the noise generated by the vacuum pumping system, one or more additional soundproofing shielding element(s) is/are provided between the hood air inlet and the pump housing air inlet and/or between the hood air outlet and the pump housing air outlet, respectively. The additional soundproofing shielding element(s) may be designed as a casing surrounding the pump housing and including a casing air inlet and a casing air outlet.

A discharge muffler for a fluid pump is formed by a cowling and a muffler insert configured to be removably inserted into a muffler receptacle of the cowling. The muffler insert includes a muffler inlet, a muffler outlet, and a plurality of muffler walls. The pump includes a pumping stage, a motor, and a drive shaft coupled between the pumping stage and the motor. When the muffler insert is inserted into the muffler receptacle, the muffler inlet communicates with the pumping stage, and the cowling and the muffler insert cooperatively define the discharge muffler. The discharge muffler is configured or effective to suppress noise generated by fluid discharged from the pumping stage.

Methods, systems, and apparatuses are disclosed to isolate operation vibration of a compressor to reduce operational sound. A compressor may include an external shell, and one or more isolators that separate a compression mechanism of a compressor from the external shell. The isolator can help isolate the vibration of the compression mechanism from the external shell. The isolator can also support a weight of the compression mechanism. The external shell can also include one or more internal seals. The internal seals can help separate a low-pressure side (e.g., a suction side) and a high-pressure side (e.g., a discharge side) of the compression mechanism. The compressor may also include a pressure balancing mechanism configured to help reduce a pressure difference between, for example, two ends of the compression mechanism, so as to reduce/eliminate the compression mechanism from physical shift in position due to the pressure difference.

A vacuum pump with a primarily cylinder-shaped pump housing is provided. A bowl-shaped sound-absorbing cover is attached on the pump housing and a circumferential gap space for sound absorption is formed between the pump housing and the sound-absorbing cover. The pump housing has an end face in which at least one air outlet opening is arranged. An elastic upstream sound absorber element is arranged between the end face and the sound-absorbing cover so that an upstream chamber is formed therebetween into which the air flows from the air outlet opening. The upstream sound absorber element has a molded projection facing the end face with an air channel passing through the projection. The projection is arranged at a distance from the end face during operation of the vacuum pump. While the vacuum pump is idle, the projection makes contact with the end face through elastic deformation of the upstream sound absorber element, causing the air channel to be closed off and creating a check valve function.

A rotary compressor includes: a shell defining an internal space; a driving motor arranged in the internal space of the shell; and a compression mechanism unit to receive power of the driving motor and compress refrigerant, wherein the compression mechanism unit includes: a cylinder defining a chamber in which the refrigerant is compressed; a rotary shaft connected to the driving motor; a roller located in the chamber and connected to the rotary shaft to compress the refrigerant in the chamber while being rotated; a bearing coupled to the cylinder and having a discharge port through which the refrigerant compressed in the chamber passes; a muffler coupled to the bearing and into which the refrigerant passing through the discharge port is introduced; and a noise reducing unit fixed to the muffler to define a noise reducing chamber together with the muffler.

An electric compressor includes a compression portion, an electric motor, an inverter, a housing, a support bracket, a vibration insulator, and a soundproofing cover. The compression portion is configured to compress a fluid. The electric motor is configured to drive the compression portion. The inverter is configured to drive the electric motor. The housing includes an outer peripheral surface that has a cylindrical shape and accommodates the compression portion, the electric motor, and the inverter. The support bracket is fastened to the housing and supports the housing to an object to which the electric compressor is mounted. The vibration insulator is interposed between the support bracket and the object. The soundproofing cover is made of an elastically deformable sound absorbing material and covers the housing and the support bracket.

The present invention relates to a compressor comprising: a muffler that provides a sealed space for guiding a refrigerant; and a resonator provided in the muffler and forming cavities separate from the sealed space to decrease vibration and noise caused by the refrigerant.