A compressor and an air conditioner having the compressor, and a protective cover of a connecting terminal of the compressor is installed while spaced apart from a barrier of the connecting terminal. The protective cover is additionally provided with a noise preventing member. Vibration generated from the compressor is delivered to the protective cover via the barrier, but as the protective cover is provided to be spaced apart from the barrier, the vibration is delivered to the barrier through the noise preventing member. Thus, regardless of the state of vibration of the compressor, noise being generated by the protective cover is minimized.

A system and method for controlling a sound level in a heating, ventilation, and air conditioning (HVAC) system are disclosed. The system includes a refrigeration unit including a compressor, a condenser fan, a controller, and a sound controller. The sound controller is configured to maintain a sound level of the refrigeration unit within a sound level operating range. A method of controlling a refrigeration unit for a heating, ventilation, and air conditioning (HVAC) system is described. The method includes determining, by a controller, a cooling requirement of a conditioned space. The controller also determines a sound level operating range for the refrigeration unit. The method further includes the controller applying a cooling setting based on the cooling requirement and the sound level operating range.

Described are a compressor driving apparatus and a refrigerator including the same. The compressor driving apparatus includes: switching elements; an inverter; an output current detector for detecting an output current flowing through a motor; and an inverter controller for controlling the inverter. The inverter controller controls the piston so that one end of the piston is fixed at a first position spaced apart from the discharge unit at stroke of the piston during a first period, controls the piston to collide with the discharge unit when a change rate in an operation rate or a position error of the compressor is equal to or greater than a predetermined value, and controls the piston so that the one end of the piston is fixed at a second position spaced apart from the discharge unit at stroke of the piston during a second period after the collision of the piston.

A control unit is configured to set a rotation speed of a compressor to be lower than that in a defrosting operation and set an opening degree of a pressure reducing device to be equal to or greater than that in the defrosting operation during a first control time after completion of the defrosting operation, stop the compressor and set the opening degree of the pressure reducing device to be less than that in the first control time during a second control time after lapse of the first control time, and control a refrigerant circuit switching device to resume a heating operation after lapse of the second control time.

A two-stage cascade refrigeration system is provided having a first refrigeration stage and a second refrigeration stage. The first refrigeration stage defines a first fluid circuit for circulating a first refrigerant, and has a first compressor, a condenser, and a first expansion device. The second refrigeration stage defines a second fluid circuit for circulating a second refrigerant, with the second refrigeration stage having a second compressor that is a variable speed compressor, a second expansion device, and an evaporator. A heat exchanger is in fluid communication with the first and second fluid circuits to exchange heat between the first and second refrigerants. A controller stages operation of the first and second compressors and runs the second compressor at an initial speed less than a maximum speed initially when a staging protocol is performed during start up or re-starting of the refrigeration system.

Suction muffler (1) for a hermetic refrigeration compressor (2), the suction muffler (1) comprising an inlet (3), so that refrigerant can flow into the suction muffler (1), and an outlet (4), so that refrigerant can flow out from the suction muffler (1), the suction muffler (1) further comprising two damping chambers (5, 6) for sound damping, where the two damping chambers (5, 6) each has a floor (8, 9) and where a wall element (11) is provided, in order to separate the two damping chambers (5, 6) from each other for the refrigerant in the region of their floors (8, 9). In order to guarantee that the damping chambers (5, 6) are overall as gas-tight and sound-tight as possible, it is provided according to the invention that in the region of the wall element (11) at least one siphon segment (16) that connects the two floors is disposed, in order to receive oil (14) in an operating position of the suction muffler (1), where the at least one siphon segment (16) connects the two damping chambers (5, 6) in siphon fashion to each other for the oil (14).

A heat dissipating blower for cooling a condenser in a refrigerator with reduced vibration and reduced noise. The heat dissipating blower includes a drive device configured to generate a rotational force, a fan coupled to the drive device, a support member configured to support the drive device, and a support frame coupled to the support member. The support member includes a fastening portion coupled to the drive device, and a connection frame spaced apart from the support frame. The heat dissipating blower further includes one or more vibration-attenuation members disposed between the connection frame and the support frame.

A refrigerant cycle device for a vehicle includes a compressor which compresses and discharges refrigerant, a discharge capacity control portion which controls a discharge capacity of the compressor. The refrigerant cycle device further includes a noise determination portion which determines whether an audible noise other than a refrigerant passing noise is in a low noise state, and/or a load determination portion which determines whether an air-conditioning thermal load is in a high load state. The discharge capacity control portion performs a gradual activation control in which the discharge capacity of the compressor is set to be lower than that determined in a normal control, when the noise determination portion determines that the audible noise is in the low noise state, and/or when the load determination portion determines that the air-conditioning thermal load is in the high load state, at an activation time of the compressor.

Provided is an expansion valve, including: a case having a valve chamber formed therein; and a valve element arranged in the valve chamber. The case includes: a side wall portion to which a first pipe is connected; and an end wall portion to which a second pipe is connected. The end wall portion has a fluid communication hole to be opened and closed by the valve element. The fluid communication hole is formed so that the following expression is satisfied: L<λ/2, where L represents an axial length of the fluid communication hole, and λ represents a resonance wavelength.

A seal includes a buckling portion. The buckling portion is composed of two H-shaped members that are flexibly connected. The two H-shaped members are buckled with each other to form a mounted state. The H-shaped member has a first arm and a second arm which are parallel to each other, and a connecting portion which connects the first arm and the second arm. The connecting portion has an arcuate surface. The arcuate surfaces of the two H-shaped members cooperatively define a hollow cavity when the two H-shaped members are in the mounted state. A vacuum assembly and a refrigerator are disclosed to respectively have the seal.