阅读说明：本技术 多功能膨胀阀和空调系统 (Multifunctional expansion valve and air conditioning system ) 是由 郑梦建 于 2018-09-06 设计创作，主要内容包括：本发明涉及一种多功能膨胀阀和空调系统。该多功能膨胀阀的阀体上设有进口、节流孔以及用于开闭节流孔的阀芯组件。阀体上还设置有两个出口,分别为第一出口和第二出口。还包括两个电磁阀。第一电磁阀的第一流体入口与节流孔连通,第一电磁阀的第一流体出口与第一出口连通。第二电磁阀的第二流体入口与节流孔连通,第二电磁阀的第二流体出口与第二出口连通。上述空调系统使用了上述多功能膨胀阀。上述多功能膨胀阀是将一个膨胀阀的功能组件和两个电磁阀集成在一个阀体上使用。这种多功能膨胀阀在使用时兼具膨胀阀和电磁阀的功能,且在空调系统中使用时,不需要设置过多的管路,从而使整个空调系统更加紧凑,系统可靠性较高。(The invention relates to a multifunctional expansion valve and an air conditioning system. The valve body of the multifunctional expansion valve is provided with an inlet, a throttling hole and a valve core assembly for opening and closing the throttling hole. The valve body is also provided with two outlets, namely a first outlet and a second outlet. Also comprises two electromagnetic valves. The first fluid inlet of the first solenoid valve is in communication with the orifice and the first fluid outlet of the first solenoid valve is in communication with the first outlet. The second fluid inlet of the second solenoid valve is in communication with the orifice and the second fluid outlet of the second solenoid valve is in communication with the second outlet. The air conditioning system uses the multifunctional expansion valve. The multifunctional expansion valve integrates the functional components of one expansion valve and two electromagnetic valves on one valve body for use. The multifunctional expansion valve has the functions of the expansion valve and the electromagnetic valve when in use, and when in use in an air conditioning system, excessive pipelines are not required to be arranged, so that the whole air conditioning system is more compact, and the system reliability is higher.)

1. A multifunctional expansion valve comprises a valve body, wherein the valve body is provided with an inlet and a throttling hole communicated with the inlet, the multifunctional expansion valve also comprises a valve core assembly for opening and closing the throttling hole, and the multifunctional expansion valve is characterized in that,

the valve body is provided with two outlets, namely a first outlet and a second outlet;

the multifunctional expansion valve also comprises two electromagnetic valves which are arranged on the valve body and are respectively a first electromagnetic valve and a second electromagnetic valve;

the first solenoid valve having a first fluid inlet in communication with the orifice and a first fluid outlet in communication with the first outlet;

the second solenoid valve has a second fluid inlet in communication with the orifice and a second fluid outlet in communication with the second outlet.

2. The multi-functional expansion valve of claim 1, wherein the valve core assembly comprises a power head, a valve core, a valve rod and a reset assembly, the power head can drive the valve rod to drive the valve core to move so as to open the orifice, and the reset assembly can drive the valve core to reset so as to close the orifice.

3. The multi-functional expansion valve of claim 2,

the power head comprises a diaphragm, a first cavity arranged on one side of the diaphragm, a second cavity arranged on the other side of the diaphragm and a piston piece arranged in the second cavity, and the piston piece is connected with the valve rod;

the valve body is provided with a balance through hole communicated with the second cavity, the balance through hole is used for fluid to pass through, and the piston piece can do reciprocating linear motion in the second cavity under the action of the diaphragm and the fluid.

4. The multi-functional expansion valve of claim 1, wherein the spool assembly comprises an electromagnetic driver and a spool, the electromagnetic driver driving the spool to move to open and close the orifice.

5. The multi-functional expansion valve of claim 4, wherein the valve body is provided with a balance through-hole for fluid passage.

6. The multi-functional expansion valve of claim 5, wherein the balance through-hole is provided therein with a temperature measuring device for measuring a temperature of the fluid flowing through the balance through-hole and a pressure measuring device for measuring a pressure of the fluid flowing through the balance through-hole, and the electromagnetic driving member controls the movement of the valve element according to detection signals of the temperature measuring device and the pressure measuring device.

7. The multi-functional expansion valve of claim 1, wherein the first solenoid valve is a normally closed solenoid valve or a normally open solenoid valve, and the second solenoid valve is a normally closed solenoid valve or a normally open solenoid valve.

8. The multi-functional expansion valve of claim 1, wherein the first outlet and the second outlet are disposed on the same side of the valve body.

9. An air conditioning system comprising a first evaporator and a second evaporator, wherein the air conditioning system further comprises the multi-function expansion valve of any one of claims 1-8, wherein a first outlet of the multi-function expansion valve is connected to an inlet of the first evaporator via a pipeline, an outlet of the first evaporator is connected to an inlet of the second evaporator via a pipeline, and a second outlet of the multi-function expansion valve is connected to an inlet of the second evaporator via a pipeline.

10. An air conditioning system according to claim 9, wherein a one-way valve is provided in the conduit between the outlet of the first evaporator and the inlet of the second evaporator to prevent fluid from the second evaporator from flowing into the first evaporator.

Technical Field

The invention relates to the technical field of expansion valves, in particular to a multifunctional expansion valve and an air conditioning system.

Background

In a conventional dual-evaporator system, a refrigerant compressed by a compressor passes through an outdoor condenser, an expansion valve and an indoor evaporator and then returns to the compressor. Wherein, two groups of electromagnetic valves connected behind the expansion valve respectively control whether the refrigerant passes through the two indoor evaporators. The system can deal with different loads by changing the working state of each evaporator, thereby achieving the best refrigeration effect. In the traditional double-evaporator system, two electromagnetic valves are independently connected behind an expansion valve, so that the cost is high, and a large number of pipeline connection points exist, and the reliability of the system is adversely affected.

Disclosure of Invention

In view of the above, it is necessary to provide a multifunctional expansion valve to solve the problem of poor system reliability caused by excessive pipe connection points.

A multifunctional expansion valve comprises a valve body, wherein an inlet and a throttling hole communicated with the inlet are formed in the valve body, the multifunctional expansion valve further comprises a valve core assembly used for opening and closing the throttling hole, and two outlets, namely a first outlet and a second outlet, are formed in the valve body; the multifunctional expansion valve also comprises two electromagnetic valves which are arranged on the valve body and are respectively a first electromagnetic valve and a second electromagnetic valve; the first solenoid valve has a first fluid inlet and a first fluid outlet, the first fluid inlet of the first solenoid valve is in communication with the orifice, and the first fluid outlet of the first solenoid valve is in communication with the first outlet; the second solenoid valve has a second fluid inlet in communication with the orifice and a second fluid outlet in communication with the second outlet.

The multifunctional expansion valve integrates the functional components of one expansion valve and two electromagnetic valves on one valve body for use. The multifunctional expansion valve has the functions of the expansion valve and the electromagnetic valve when in use, and when in use in an air conditioning system, excessive pipelines are not required to be arranged, so that the whole air conditioning system is more compact, and the system reliability is higher.

In one embodiment, the valve core assembly comprises a power head, a valve core, a valve rod and a reset assembly, the power head can drive the valve rod to drive the valve core to move so as to open the throttling hole, and the reset assembly can drive the valve core to reset so as to close the throttling hole.

In one of the embodiments, the first and second electrodes are,

the unit head includes the diaphragm, set up at the first cavity of diaphragm one side, set up at the second cavity of diaphragm opposite side and set up the piston spare in the second cavity, the piston spare links to each other with the valve rod, be provided with the balanced through-hole with the second cavity intercommunication on the valve body, balanced through-hole is used for the fluid to pass through, the piston spare can make reciprocal linear motion in the second cavity under diaphragm and fluid effect.

In one embodiment, the valve core assembly comprises an electromagnetic driver and a valve core, and the electromagnetic driver drives the valve core to move to open and close the throttle hole.

In one embodiment, the valve body is provided with a balance through hole for fluid to pass through.

In one embodiment, a temperature measuring device for detecting the temperature of the fluid flowing through the balance through hole and a pressure measuring device for detecting the pressure of the fluid flowing through the balance through hole are arranged in the balance through hole, and the electromagnetic driving piece controls the valve core to move according to detection signals of the temperature measuring device and the pressure measuring device.

In one embodiment, the first electromagnetic valve is a normally closed electromagnetic valve or a normally open electromagnetic valve, and the second electromagnetic valve is a normally closed electromagnetic valve or a normally open electromagnetic valve.

In one embodiment, the first outlet and the second outlet are disposed on the same side of the valve body.

In one embodiment, the first solenoid valve and the second solenoid valve are respectively arranged on two opposite sides of the valve body.

The invention also provides an air conditioning system, which comprises a first evaporator and a second evaporator, and further comprises the multifunctional expansion valve, wherein a first outlet of the multifunctional expansion valve is connected with an inlet of the first evaporator through a pipeline, an outlet of the first evaporator is connected with an inlet of the second evaporator through a pipeline, and a second outlet of the multifunctional expansion valve is connected with an inlet of the second evaporator through a pipeline.

In one embodiment, a one-way valve is disposed on a pipeline between the outlet of the first evaporator and the inlet of the second evaporator, and is used for preventing the fluid of the second evaporator from flowing into the first evaporator.

Drawings

Fig. 1 is a front view of a multi-function expansion valve of an embodiment of the present invention comprised of the functional components of a thermostatic expansion valve and two solenoid valves;

FIG. 2 is a sectional view taken along line A-A of FIG. 1;

fig. 3 is a rear view of the multi-function expansion valve of an embodiment of the present invention comprised of the functional components of a thermostatic expansion valve and two solenoid valves;

FIG. 4 is a sectional view taken along line B-B of FIG. 3;

fig. 5 is a front view of the multi-functional expansion valve of the embodiment of the present invention composed of the functional components of the electronic expansion valve and two solenoid valves and having balancing through holes;

FIG. 6 is a sectional view taken along line A-A of FIG. 5;

FIG. 7 is a sectional view taken along line B-B of FIG. 5;

fig. 8 is a rear view of the multi-functional expansion valve of the embodiment of the present invention composed of the functional components of the electronic expansion valve and two solenoid valves and having balancing through-holes;

fig. 9 is a front view of the multi-function expansion valve of the embodiment of the present invention comprised of the functional components of the electronic expansion valve and two solenoid valves;

FIG. 10 is a sectional view taken along line A-A of FIG. 9;

fig. 11 is a rear view of the multi-function expansion valve of the embodiment of the present invention comprised of the functional components of the electronic expansion valve and two solenoid valves;

FIG. 12 is a sectional view taken along line B-B of FIG. 11;

fig. 13 is a schematic view illustrating that a first solenoid valve is open and a second solenoid valve is closed in a multi-functional expansion valve of an air conditioning system according to an embodiment of the present invention;

fig. 14 is a schematic view showing a first solenoid valve and a second solenoid valve in a multifunction expansion valve of an air conditioning system according to an embodiment of the present invention;

fig. 15 is a schematic view showing that a first solenoid valve is closed and a second solenoid valve is opened in a multi-function expansion valve of an air conditioning system according to an embodiment of the present invention;

fig. 16 is a schematic view of an air conditioning system according to an embodiment of the present invention in which a check valve is provided between a first evaporator and a second evaporator.

Wherein:

100. multifunctional expansion valve 110, valve body 120 and inlet

131. A first solenoid valve 131a, a first fluid inlet 131b, a first fluid outlet

132. A second solenoid valve 132a, a second fluid inlet 132b, a second fluid outlet

141. First outlet 142, second outlet 150, balancing through hole

161. Power head 161a, diaphragm 161b, first chamber

161c, a second chamber 161d, a piston member 162, a valve stem

163. Valve core 164, reset assembly 164a and valve core seat

164b, mount 164c, return spring 170, orifice

181. Electromagnetic driving piece 182, valve core 200 and air conditioning system

201. Indoor air conditioning assembly 201a, first evaporator 201b, second evaporator

201c, check valve 202, compressor 203, condenser

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

As shown in fig. 1 to 4, an embodiment of the present invention provides a multi-functional expansion valve 100, which includes a valve body 110, wherein the valve body 110 is provided with an inlet 120 and an orifice 170 communicating with the inlet 120, the multi-functional expansion valve 100 further includes a valve core assembly for opening and closing the orifice 170, and the valve body 110 is provided with two outlets, namely a first outlet 141 and a second outlet 142. The above-described multi-function expansion valve 100 further includes two solenoid valves, a first solenoid valve 131 and a second solenoid valve 132, mounted on the valve body 110. The first solenoid valve 131 has a first fluid inlet 131a and a first fluid outlet 131b, the first fluid inlet 131a of the first solenoid valve 131 communicates with the orifice 170 to receive the fluid flowing out of the orifice 170, and the first fluid outlet 131b of the first solenoid valve 131 communicates with the first outlet 141. The second solenoid valve 132 has a second fluid inlet 132a and a second fluid outlet 132b, the second fluid inlet 132a of the second solenoid valve 132 communicates with the orifice 170 to receive the fluid flowing out of the orifice 170, and the second fluid outlet 132b of the second solenoid valve 132 communicates with the second outlet 142.

The above-described multi-function expansion valve 100 is used by integrating the functional components of one expansion valve and two solenoid valves into one valve body 110. The multifunctional expansion valve 100 has functions of an expansion valve and a solenoid valve when in use, and when in use in an air conditioning system, excessive pipelines are not required to be arranged, so that the whole air conditioning system is more compact, and the system reliability is higher.

When the multi-function expansion valve 100 is operated, fluid can flow in from the inlet 120 of the valve body 110, and after the valve core assembly is opened, the fluid can flow to the first solenoid valve 131 and the second solenoid valve 132 through the orifice 170. When the first solenoid valve 131 is opened, the fluid may flow to the first outlet 141 provided on the valve body 110 through the first fluid inlet 131a and the first fluid outlet 131b of the first solenoid valve 131, and flow to a subsequent device through the first outlet 141. When the first solenoid valve 131 is closed, the communication between the first fluid inlet 131a and the first fluid outlet 131b is interrupted. When the second solenoid valve 132 is opened, the fluid may flow to the second outlet 142 provided on the valve body 110 through the second fluid inlet 132a and the second fluid outlet 132b of the second solenoid valve 132, and flow to the subsequent equipment through the second outlet 142. When the second solenoid valve 132 is closed, communication between the second fluid inlet 132a and the second fluid outlet 132b is interrupted. The first solenoid valve 131 and the second solenoid valve 132 may be opened simultaneously or only one of the solenoid valves may be opened. The specific starting condition can be selected according to actual use requirements.

The above-mentioned multifunction expansion valve 100 can be applied to a functional component of a thermostatic expansion valve or to a functional component of an electronic expansion valve.

For example, as shown in fig. 1-4, the multi-function expansion valve 100 described above employs functional components of a thermostatic expansion valve. The valve plug assembly includes a power head 161, a valve plug 163, a valve stem 162 and a reset assembly 164, the power head 161 can drive the valve stem 162 to drive the valve plug 163 to move so as to open the orifice 170, and the reset assembly 164 can drive the valve plug to reset so as to close the orifice 170.

When the valve stem 162 moves the valve element to open the orifice 170, the inlet 120 of the valve body 110 is communicated with the first fluid inlet 131a and the second fluid inlet 132a through the orifice 170. When the reset assembly 164 drives the valve core 163 to move in reverse to close the orifice 170, the communication between the inlet 120 of the valve body 110 and the first and second fluid inlets 131a and 132a is cut off.

The power head 161 and reset assembly 164 described above may be implemented using power head and reset assemblies commonly used in the art for thermal expansion valves. For example, the powerhead 161 may include a diaphragm 161a, with the diaphragm 161a providing a first chamber 161b on one side and a second chamber 161c on the other side. The first chamber 161b is provided with a medium having a certain pressure. A piston member 161d is provided in the second chamber 161 c. The piston member 161d is connected to the valve stem 162. The second chamber 161c of the powerhead 161 also communicates with the outlet of the evaporator via an external balance tube. Thus, the refrigerant flowing out of the evaporator outlet may generate a constant pressure to the piston member 161d in the second chamber 161 c. Because the two sides of the piston member 161d are respectively subjected to the pressure of the diaphragm 161a and the pressure of the refrigerant, when the two pressures are unbalanced, the piston member 161d will move relative to the second chamber 161c, and further drive the valve rod 162 to move, and when the two pressures are balanced, the piston member 161d is stationary relative to the second chamber 161 c. The reset assembly 164 may include a valve cartridge 164a, a mounting seat 164b, and a reset spring 164c interposed between the valve cartridge 164a and the mounting seat 164 b. The piston member 161d drives the valve stem 162 to push the spool 163 downward and compresses the return spring 164c to open the orifice 170. At this time, the inlet port 120 of the valve body 110, the orifice 170, the first fluid inlet 131a, and the second fluid inlet 132a communicate. When the return spring 164c pushes the spool 163 upward to move to return, the orifice 170 may be closed. At this time, the communication between the inlet 120 of the valve body 110 and the first and second fluid inlets 131a and 132a is interrupted.

In this embodiment, the power head 161 includes a diaphragm 161a, a first chamber 161b disposed on one side of the diaphragm 161a, a second chamber 161c disposed on the other side of the diaphragm 161a, and a piston member 161d disposed in the second chamber 161c, the piston member 161d is connected to the valve stem 162, the valve body 110 is provided with a balance through hole 150 communicating with the second chamber 161c, the balance through hole 150 is used for fluid to pass through, and the piston member 161d can reciprocate in the second chamber 161c under the action of the diaphragm 161a and the fluid. Both ends of the balance through hole 150 may be connected to a refrigerant outlet of the evaporator and a refrigerant inlet of the compressor 202, respectively. The refrigerant flowing out of the evaporator may flow into the balance through hole 150, and since the refrigerant may contact the piston member 161d, the refrigerant may apply a certain pressure P1 to the piston member 161d, and the first chamber 161b on the side of the diaphragm 161a may be filled with a medium, and the medium may generate a pressure P2 to the piston member 161d through the diaphragm 161 a. The movement of the piston member 161d, and therefore the moving distance of the valve stem 162 connected to the piston member 161d, can be controlled by the difference between P1 and P2, and accordingly the opening degree of the valve core can be controlled.

As shown in fig. 5 to 12, the above-mentioned multi-functional expansion valve 100 may also be applied to a functional component of an electronic expansion valve. Accordingly, the valve core assembly includes an electromagnetic driving member 181 and a valve core 182, and the electromagnetic driving member 181 drives the valve core 182 to move to open and close the throttle hole 170. When the solenoid driver 181 drives the spool 182 to open the orifice 170, the inlet 120 of the valve body 110 communicates with the first fluid inlet 131a and the second fluid inlet 132a through the orifice 170. When the solenoid driver 181 drives the spool 182 to close the orifice 170, the passage between the inlet 120 and the first and second fluid inlets 131a and 132a in the valve body 110 is cut off.

The electromagnetic driving element 181 and the valve core 182 can be applied to the electromagnetic driving element and the valve core of the electronic expansion valve in the prior art, as long as the movement of the valve core can be controlled. For example, when the solenoid driver 181 drives the spool 182 downward, the spool closes the orifice 170 to interrupt communication between the inlet port 120 of the valve body 110 and the first and second fluid inlet ports 131a and 132 a. When the solenoid driver 181 drives the spool 182 upward, the spool 182 opens the orifice 170 to communicate the inlet port 120 of the valve body 110 with the first and second fluid inlet ports 131a and 132 a. It will be appreciated that the reverse arrangement is also possible, for example, when the solenoid driver 181 drives the spool 182 upward, the spool 182 closes the orifice 170 to interrupt communication between the inlet 120 of the valve body 110 and the first and second fluid inlets 131a, 132 a. When the solenoid driver 181 drives the spool 182 downward, the spool 182 opens the orifice 170 to communicate the inlet port 120 of the valve body 110 with the first and second fluid inlet ports 131a and 132 a.

The first solenoid valve 131 may be a normally closed solenoid valve or a normally open solenoid valve, and similarly, the second solenoid valve 132 may be a normally closed solenoid valve or a normally open solenoid valve.

In this embodiment, the valve body 110 is provided with a balance through hole 150, and the balance through hole 150 is used for fluid to pass through. For example, the balance through hole 150 may communicate at both ends thereof with the outlet of the evaporator and the inlet 120 of the compressor 202 through pipes, respectively.

In this embodiment, a temperature measuring device for measuring a temperature of the fluid flowing through the balance through hole 150 and a pressure measuring device for measuring a pressure of the fluid flowing through the balance through hole 150 are disposed in the balance through hole 150, and the electromagnetic driving member 181 controls the valve element to move according to detection signals of the temperature measuring device and the pressure measuring device. The temperature measuring device can be a temperature sensor and the like. The pressure measuring device can be a pressure sensor and the like. After the refrigerant flowing out of the outlet of the evaporator enters the balance through hole 150, the temperature sensor obtains a temperature signal of the refrigerant, the temperature signal is sent to the electromagnetic driving part 181, the pressure sensor obtains a pressure signal of the refrigerant, and the pressure signal is sent to the electromagnetic driving part 181. The solenoid driver 181 receives the temperature signal and the pressure signal, and controls the movement of the spool according to the temperature signal and the pressure signal, thereby controlling the opening degree of the orifice 170.

In this embodiment, the first outlet 141 and the second outlet 142 are disposed on the same side of the valve body 110. With this configuration, the pipe connecting the first outlet 141 and the second outlet 142 can be fixed to the valve body 110 by a fixing plate, thereby simplifying the structure of the fixing plate. Meanwhile, the distance between the two pipelines can be shortened due to the arrangement of the two outlets on the same side, so that the pipeline layout is more compact.

In this embodiment, the first solenoid valve 131 and the second solenoid valve 132 are disposed on opposite sides of the valve body 110. By this arrangement, the balance weights on both sides of the valve body 110 can be balanced. And, the design is such that the inlet port 120, the first outlet port 141 and the second outlet port 142 can be disposed on the other two opposite sides of the valve body 110. In this way, it is possible to facilitate connection of the respective pipes to the inlet 120, the first outlet 141 and the second outlet 142. There is no interference from the first and second solenoid valves 131 and 132 when installing the piping.

As shown in fig. 13 to 16, the present invention further provides an air conditioning system 200, which includes a compressor 202, a condenser 203, a first evaporator 201a and a second evaporator 201b, and the above-mentioned multifunction expansion valve 100. The first evaporator 201a and the second evaporator 201b may be installed indoors as a component of the indoor air conditioning assembly 201.

The first outlet 141 of the multi-function expansion valve 100 is connected to an inlet of the first evaporator 201a through a pipe, an outlet of the first evaporator 201a is connected to an inlet of the second evaporator 201b through a pipe, and the second outlet 142 of the multi-function expansion valve 100 is connected to an inlet of the second evaporator 201b through a pipe.

When the above-mentioned multifunction expansion valve 100 is provided with the balance through-hole 150, the outlet of the second evaporator 201b is connected to one end of the balance through-hole 150 through a pipe, the other end of the balance through-hole 150 is connected to the inlet of the compressor 202 through a pipe, the outlet of the compressor 202 is connected to the inlet of the condenser 203 through a pipe, and the outlet of the condenser 203 is connected to the inlet 120 of the multifunction expansion valve 100 through a pipe.

When the above-described multifunction expansion valve 100 is not provided with the balance through-hole 150, the outlet of the second evaporator 201b is connected to the inlet of the compressor 202 through a pipe, the outlet of the compressor 202 is connected to the inlet of the condenser 203 through a pipe, and the outlet of the condenser 203 is connected to the inlet 120 of the multifunction expansion valve 100 through a pipe.

In use, when only the first solenoid valve 131 is in an open state and the second solenoid valve 132 is in a closed state, all of the refrigerant flowing out of the multi-function expansion valve 100 passes through the first evaporator 201a and the second evaporator 201b in sequence. Therefore, the heat exchange areas of the two evaporators are fully utilized, and the evaporator is suitable for high-load working conditions.

If both the first solenoid valve 131 and the second solenoid valve 132 are in the open state, a part of the refrigerant flowing out of the multi-functional expansion valve 100 flows through the first evaporator 201a and the second evaporator 201b from the first outlet 141 in sequence, thereby making full use of the heat exchange area of both evaporators, and the other part of the refrigerant flows to the second evaporator 201b through the second outlet 142, thereby making use of only the heat exchange area of the second evaporator 201 b. This mode of operation is suitable for medium load conditions.

If only the second solenoid valve 132 is opened and the first solenoid valve 131 is closed, all the refrigerant flowing from the multi-function expansion valve 100 flows to the second evaporator 201b through the second outlet 142, and only the heat exchange area of the second evaporator 201b is used. This mode of operation is suitable for low load conditions.

In this embodiment, a check valve 201c is disposed between the outlet of the first evaporator 201a and the inlet of the second evaporator 201b to prevent the fluid of the second evaporator 201b from flowing into the first evaporator 201 a. With this arrangement, when the indoor second evaporator 201b is used only, the refrigerant is prevented from flowing back into the first evaporator 201a, which may affect the cooling effect.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.