Systems and methods are presented for improving stabilization of a heating, ventilating, and air conditioning (HVAC) system. More specifically, the systems and methods include a heat-flow modulator for regulating an exchange of thermal energy between a flow of refrigerant and a sensory bulb. The exchange of thermal energy allows an expansion valve to respond to a refrigerant temperature using an actuator, which is coupled to the sensory bulb. The heat-flow modulator is formed of a body that includes a first contact surface and a second contact surface. The first contact surface is thermally-coupled to a suction line of the HVAC system, which conveys the flow of refrigerant. The second contact surface is thermally-coupled to the sensory bulb. In one instance the heat-flow modulator has variable volume depending on how installed. Other systems and methods are presented. Variable heat-flow modulators are also presented.

A control method and a control system are provided. A valve closing position of a valve device can be controlled according to the current flow direction or working mode of a refrigerant. A stroke of the valve device from a fully-opened position to a fully-closed position is defined as a total valve closing stroke. When the flow direction of the refrigerant is a forward direction, the valve device is controlled to operate at a first valve closing position, and when the flow direction of the refrigerant is a reverse direction, the valve device is controlled to operate at a second valve closing position. The first valve closing position is different from the second valve closing position, such that wear caused by valve closing can be reduced.

An expansion valve includes a valve body that is designed as a converging-diverging nozzle that tapers from an inlet end and an outlet end thereof towards a throat. The valve body includes an inlet opening, an outlet opening, and a refrigerant flow path that are co-axial, the refrigerant flow path extending through the valve body from the inlet opening to the outlet opening. A portion of the valve body is flexible and configured to be adjusted by application of an external force to throttle the valve body at the throat and thereby control a flow of the refrigerant through the refrigerant flow path. Further, the expansion valve includes a force applying assembly that is coupled to the flexible portion of the valve body to apply the external force thereon. The force applying assembly is disposed external to the refrigerant flow path and removably coupled to the valve body.

A refrigeration cycle apparatus includes: a compressor; a condenser; an expansion valve; an evaporator; and a control device. The compressor compresses refrigerant. The condenser condenses the refrigerant output from the compressor. The expansion valve decompresses the refrigerant output from the condenser. The evaporator evaporates the refrigerant output from the expansion valve for output to the compressor. In the case of stopping the compressor, the control device executes control for increasing a degree of superheat of the refrigerant output from the evaporator to the compressor, and then stops the compressor.

A valve drive device comprising a valve body drive mechanism including a drive gear, a driven gear for turning the valve body, and a power transmission switching part provided with a protruded part of the drive gear and a turning restriction part turnably attached to the driven gear. The turning restriction part comprises a lever part urged with an urging force toward an outer side of the driven gear. The driven gear comprises a lever turning restriction part for restricting turning of the lever part and the lever part is structured to perform a contact operation with the protruded part and a separating operation separated from a contact position with the lever turning restriction part. The valve body drive mechanism further comprises a foreign matter entry restraining part which covers at least a part of a region formed between the lever part and the lever turning restriction part.

An electronic expansion valve includes a valve seat component, including a valve seat and a valve core seat; and a valve rod component, capable of axially moving along a core cavity of the valve core seat to open or close a valve port. The valve rod component is provided with an axial through hole communicated with the valve port and a sealing surface capable of being adhered to and sealing the valve port. The valve rod component includes a valve rod and a valve core fixedly disposed at a lower end of the valve rod. The valve rod is a cylindrical body, including a small-diameter cylinder body and a large-diameter cylinder body close to the valve port. A first gap is provided between the large-diameter cylinder body and the valve core seat, and a second gap is provided between the valve core and the valve port.

A thermal expansion valve includes a power head and a valve body. The power head and the valve body are fixedly arranged. The power head includes a power head cover, a power head seat, and a membrane. The membrane includes a membrane recess and a corrugated portion. The membrane recess is located at the center position of the membrane. The corrugated portion is located at the peripheral position of the membrane recess. The membrane recess is recessed away from the power head cover. The valve body comprises a top portion. The top portion is provided with an opening. At least a part of the power head is extended into the opening. With an axial direction of the valve body as a projection direction, a projection of the power head towards the top portion falls on the top portion.

Disclosed is an air conditioner and control method thereof. The air conditioner and control method thereof is to improve rapid heating performance without using a large-capacity compressor. The air conditioner includes an indoor unit having a first heat exchanger, an outdoor unit having a compressor and a second heat exchanger, a refrigerant cycle configured to form a refrigerant circulation path between the indoor unit and the outdoor unit, a flow path switch configured to switch a flow of a refrigerant in the refrigerant cycle, and a controller configured to control the flow path switch to allow one part of the refrigerant discharged from the compressor to flow into an inlet of the compressor and the other part of the refrigerant discharged from the compressor to flow into at least one of the first heat exchanger and the second heat exchanger.

An air conditioner includes a refrigerant circuit and refrigerant. The refrigerant circuit has a compressor, a condenser, a pressure-regulating valve, and an evaporator. The refrigerant is R32. The pressure-regulating valve includes a flow path causing the refrigerant flowing from the condenser to flow to the evaporator, a pressure reference chamber partitioned from the flow path and filled with inert gas, and a valve portion. The pressure-regulating valve is configured to adjust a degree of opening of the valve portion to adjust a flow rate of the refrigerant flowing through the flow path. The valve portion is configured to increase the degree of opening when a pressure in the flow path is higher than a pressure in the pressure reference chamber, and reduce the degree of opening when the pressure in the flow path is lower than the pressure in the pressure reference chamber.

An apparatus is for diagnosing a valve failure of a refrigerator by detecting whether or not a first valve configured to control flow of a refrigerant circulating in a first refrigeration compartment and a second valve configured to control flow of a refrigerant circulating in a second refrigeration compartment are abnormal. The apparatus includes a first temperature sensor measuring a temperature in the first refrigeration compartment, a second temperature sensor measuring a temperature in the second refrigeration compartment, and a controller configured to determine whether or not the first valve and the second valve are abnormal by comparing changes in temperatures measured by the first temperature sensor and the second temperature sensor in a state where the first valve or the second valve is opened. The apparatus further includes a display configured to display the determination result indicating whether or not the first valve and the second valve are abnormal.