Provided is a throttle device to decompress a refrigerant cooled by a condenser in a refrigerating cycle and to deliver the refrigerant to an evaporator, where a minimum space between a needle valve and a valve port can be accurately set. Inside a cylindrical main body case including a primary chamber connected to the condenser and a secondary chamber connected to the evaporator, a valve seat member formed with a valve port and a cylindrical guide member integral to the valve seat member are provided. A coil spring to energize the needle valve toward the valve port side is provided inside the guide member. A needle portion of the needle valve protrudes from the valve port toward the primary chamber. A tip portion of the needle portion abuts against a stopper member and the tip portion is thereby positioned.

An air conditioning system is provided. The system has a high-pressure pipe, a low-pressure pipe, an indoor heat exchanger, an outdoor heat exchanger, a leak-free thermal expansion valve and a variable capacity compressor. The variable capacity compressor has a shell, a first cylinder and a second cylinder. The shell has a suction port and an exhaust port. The first cylinder has a first suction hole connected to the suction port and a first exhaust hole connected to the exhaust port. The second cylinder has a second suction hole connected to the suction port, a second exhaust hole connected to the exhaust port, and a pressure relief hole connected to the high-pressure pipe and the low-pressure pipe in an on-off manner. Before the variable capacity compressor is started, the high-pressure pipe and the low-pressure pipe are connected and also disconnected after the first preset duration.

An air conditioning system is provided. The system has a high-pressure pipe, a low-pressure pipe, an indoor heat exchanger, an outdoor heat exchanger, a leak-free thermal expansion valve and a variable capacity compressor. The variable capacity compressor has a shell, a first cylinder and a second cylinder. The shell has a suction port and an exhaust port. The first cylinder has a first suction hole connected to the suction port and a first exhaust hole connected to the exhaust port. The second cylinder has a second suction hole connected to the suction port, a second exhaust hole connected to the exhaust port, and a pressure relief hole connected to the high-pressure pipe and the low-pressure pipe in an on-off manner. Before the variable capacity compressor is started, the high-pressure pipe and the low-pressure pipe are connected and also disconnected after the first preset duration.

In a throttle device, a body portion has a flat surface at a position at a predetermined distance from its center axis. Thus, when a needle member is moving, a working pressure of a refrigerant present between an inner peripheral surface of a guide tube and the flat surface acts in a radial direction of the body portion and presses part of an outer peripheral surface of the body portion located opposite from the flat surface against the inner peripheral surface of the guide tube.

The application relates to a cooling system, the cooling system having: an evaporator, a first compressor, a second compressor, a cooling component, an expansion device and a line system that connects the evaporator, the first compressor, the second compressor, the cooling component and the expansion device to one another. The cooling system includes a refrigerant, wherein the refrigerant comprises carbon dioxide. The first compressor and the second compressor are arranged in series with one another. The application also relates to a corresponding laboratory instrument.

The application relates to a cooling system, the cooling system having: an evaporator, a first compressor, a second compressor, a cooling component, an expansion device and a line system that connects the evaporator, the first compressor, the second compressor, the cooling component and the expansion device to one another. The cooling system includes a refrigerant, wherein the refrigerant comprises carbon dioxide. The first compressor and the second compressor are arranged in series with one another. The application also relates to a corresponding laboratory instrument.

An electronic expansion valve (1) is provided, comprising an inlet (9), an outlet (8), an armature (2), a stop member (3), a biasing member (4) and a solenoid coil (12). The biasing member (4) provides a biasing force on the armature (2) towards a closing direction while the solenoid coil (12) may be provided with a current to provide a magnetic force on the armature (2) towards an opening direction. It is intended to provide an electronic expansion valve that may be controlled more precisely and has a higher safety. To this end the pressure difference between the inlet pressure and the outlet pressure provides a differential pressure force on the armature (2) towards an opening direction to allow a fluid flow from the inlet (9) to the outlet (8), and furthermore the armature (2) is displaced away from the stop member (3) to allow a fluid flow from the inlet (9) to the outlet (8) if the sum of the magnetic force and the differential pressure force on the armature (2) exceeds the biasing force. The invention furthermore relates to a refrigeration system comprising such an electronic expansion valve as well as a method for calibrating such an electronic expansion valve.

An expansion valve of an air conditioning system for a vehicle includes: a body member where a first path and a second path that are separate from each other are formed; a movement member combined to be movable in a predetermined direction in the body member, one end of the movement member being exposed to the first path and receiving a pressure of the first path and another end opening/closing the second path; and an elastic member provided to elastically support the movement member in a direction of the first path, where as the movement member ascends or descends due to a difference between an internal pressure of the first path and an elastic force of the elastic member, the second path may be closed or opened.

Provided is a throttle device to decompress a refrigerant cooled by a condenser in a refrigerating cycle and to deliver the refrigerant to an evaporator, where a minimum space between a needle valve and a valve port can be accurately set. Inside a cylindrical main body case including a primary chamber connected to the condenser and a secondary chamber connected to the evaporator, a valve seat member formed with a valve port and a cylindrical guide member integral to the valve seat member are provided. A coil spring to energize the needle valve toward the valve port side is provided inside the guide member. A needle portion of the needle valve protrudes from the valve port toward the primary chamber. A tip portion of the needle portion abuts against a stopper member and the tip portion is thereby positioned.

In a throttle device, a needle member (20) includes a tapered portion (20P) having a taper angle (2), and a length (X) along a center axis from a position (20PS) to an apical surface of the tapered portion (20P) is set to a value equal to or above a prescribed amount of lift (Lcos.sup.2), where the position (20PS) is a position corresponding to an edge (22as) of a valve port (22a) in a state where the tapered portion (20P) is inserted in the valve port (22a) and establishes a closed state of the valve port (22a).