An expansion valve

Abstract

The present invention provides an expansion valve, belonging to the technical field of air conditioning components. It solves the problem of low flow control accuracy of existing expansion valves. The expansion valve comprises a tubular valve body and two valve cores slidably arranged in the valve body, the valve body is provided with two limiting parts, the two valve cores are located between the two limiting parts, one of the valve cores has a through throttling hole, the other valve core has a plug connector on its end face, the plug connector has a plurality of annular throttling surfaces with different diameters along the length direction on the outer circumference of the plug connector and / or the inner circumference of the throttling hole, a spring seat is slidably arranged between the valve core and the limiting part at the same end of the valve body, a spring 1 is arranged between the valve core and the spring seat, a spring 2 is arranged between the spring seat and the limiting part, and the spring 1 and spring 2 have different stiffness coefficients. The flow control accuracy of the expansion valve is higher.

Description

Technical Field

[0001] The invention belongs to the technical field of air-conditioning components and relates to an expansion valve. Background Art

[0002] The compressor, condenser, expansion valve and evaporator together constitute the refrigeration system. The expansion valve is an important component in the refrigeration system and is generally installed between the condenser and the evaporator. The expansion valve can pressurize and liquefy the gas evaporated by the evaporator into a high-temperature and high-pressure liquid refrigerant through the compressor, and throttle it through its throttle port to become a low-temperature and low-pressure mist liquid refrigerant. The refrigerant then absorbs heat in the evaporator to achieve a refrigeration effect.

[0003] For example, the expansion valve disclosed in the patent application (application number: 201711366377.9) includes a valve core 1 and a columnar valve core 2, the valve core 1 has a through throttling hole, and the end face of the valve core 2 has a columnar plug connector that can be inserted into the throttling hole, the outer diameter of the plug connector is smaller than the outer diameter of the valve core 2, the inner wall of the throttling hole has at least two straight cylindrical surfaces of different diameters from the orifice to the inside, and the outer wall of the plug connector has at least two annular throttling walls of different diameters, when the plug connector is inserted into the throttling hole, the throttling wall can be opposite to the straight cylindrical surface and form a throttling channel, when heating, the refrigerant pushes the valve core 1 to compress the spring 1 to achieve three-level heating flow control, and when cooling, the refrigerant pushes the valve core 2 to compress the spring 2 to achieve three-level cooling flow control, but different flow levels are controlled by compressing the same spring to different positions, and the precision of multi-segment control of the spring with a fixed stiffness coefficient is low, which leads to relatively low precision of the three-level flow control. Summary of the invention

[0004] The purpose of the present invention is to solve the problem of low flow control accuracy of the existing expansion valve by proposing an expansion valve in view of the above problems in the existing technology.

[0005] The objectives of the present invention can be achieved through the following technical solutions: an expansion valve, comprising a tubular valve body and two valve cores slidably arranged in the valve body, the valve body having two limiting parts, the two valve cores being located between the two limiting parts, one of the valve cores having a through throttling hole, and the other valve core having a plug connector on its end face which is columnar and can be inserted into the throttling hole to form a throttling channel, characterized in that the outer circumferential surface of the plug connector and / or the inner circumferential surface of the throttling hole have a plurality of annular throttling surfaces with different diameters along the length direction, a spring seat is slidably arranged between the valve core and the limiting part at the same end of the valve body, a spring 1 is arranged between the valve core and the spring seat, a spring 2 is arranged between the spring seat and the limiting part, and the spring 1 and spring 2 have different stiffness coefficients.

[0006] When the air conditioner is heating the room, the gaseous refrigerant flows in from the port at one end of the valve body, which is called the heating inlet. The refrigerant pushes the valve core with a throttling hole to move, and the throttling channel opens and the cross-sectional area is adjusted by moving the valve core. When the air conditioner is cooling the room, the liquid refrigerant flows in from the port at the other end of the valve body, which is called the cooling inlet. The refrigerant pushes the valve core with a plug-in connector to move. Similarly, the throttling channel opens and the cross-sectional area is adjusted by moving the valve core. Since a slidable spring seat is provided, at least two structures are included. The first structure is that a spring seat is provided between the valve core with a plug connector and the limiting part, so that the valve core with the plug connector is controlled by spring one and spring two, and an existing spring structure is adopted between the valve core with a throttling hole and the limiting part. Therefore, the expansion valve controls the flow in the cooling mode by two springs, spring one and spring two, and controls the flow in the heating mode by one spring. The second structure is that spring seats are provided between the two valve cores and the corresponding limiting parts, so that spring one and spring two can be respectively provided at both ends of the spring seats, that is, the cooling mode and the heating mode are both flow controlled by two springs, and the spring one and spring two have different stiffness coefficients, so that spring one and spring two can work in time sharing, thereby improving the accuracy of the throttling channel through cross-sectional area adjustment, that is, improving the flow control accuracy.

[0007] Specifically, taking the example that both valve cores are controlled by spring one and spring two, when indoor heating is performed, the gaseous refrigerant flows into the heating inlet and pushes the valve core with a throttling hole, and the valve core compresses the corresponding spring one until the valve core is in contact with the spring seat. In this process, the throttling channel formed by the corresponding throttling surface is used for the intermediate heating mode, and the valve core pushes the spring seat so that the spring seat compresses a part of spring two, but has not yet contacted the limiting part. In this process, the throttling channel formed by the corresponding throttling surface is used for the rated heating mode, and the spring seat continues to compress spring two until it is in contact with the limiting part. In this process, the throttling channel formed by the corresponding throttling surface is used for the maximum heating mode.

[0008] When indoor cooling is performed, liquid refrigerant flows into the cooling inlet and pushes the valve core with a plug connector. The valve core compresses the corresponding spring 1 until the valve core is in contact with the spring seat. In this process, the throttling channel formed by the corresponding throttling surface is used for the intermediate cooling mode. The valve core pushes the spring seat, so that the spring seat compresses a part of the spring 2, but has not yet contacted the limiting part. In this process, the throttling channel formed by the corresponding throttling surface is used for the rated cooling mode. The spring seat continues to compress the spring 2 until it is in contact with the limiting part. In this process, the throttling channel formed by the corresponding throttling surface is used for the maximum cooling mode.

[0009] That is, this structure realizes a total of six flow level working modes for heating and cooling, and when heating or cooling, the three working modes with different flow rates are separately controlled by spring one and spring two, where spring one controls one working mode, and spring two combined with the limit part controls two working modes, so the flow control accuracy is higher.

[0010] In the above expansion valve, the spring coefficient of the first spring is smaller than that of the second spring, and the starting elastic force of the second spring is greater than the elastic force when the first spring is compressed to the point where the valve core abuts against the spring seat. The first spring has a smaller spring coefficient, so that the valve core first compresses the first spring, and the spring seat can remain stationary, thereby reducing the pressure requirement at the heating port in the initial stage of heating. The second spring has a larger starting elastic force, so that the second spring remains stationary during the compression of the first spring, thereby avoiding mutual interference and affecting the flow control accuracy.

[0011] In the above-mentioned expansion valve, there are at least six throttling surfaces and all are located on the plug connector. The throttling surfaces are arranged in sequence from large to small in diameter along the insertion direction of the plug connector. The inner circumferential surface of the throttling hole has an annular mating surface, and a throttling channel is formed between the mating surface and the relative throttling surface. There are six throttling surfaces in this structure, and their diameters are different. When the mating surface is opposite to the corresponding throttling surface, a corresponding throttling channel is formed between the two. Therefore, the larger the diameter of the throttling surface, the smaller the cross-sectional area of ​​the throttling channel. Since the refrigerant is in gaseous form during heating, the required passing area is smaller, and the refrigerant is in liquid form during cooling, the required passing area is larger. Therefore, along the insertion direction of the plug connector, the diameters are arranged from large to small in order: the intermediate heating throttling surface, the rated heating throttling surface, the maximum heating throttling surface, the intermediate cooling throttling surface, the rated cooling throttling surface and the maximum cooling throttling surface. That is, unlike the prior art in which the throttling surface is partially arranged on the outer wall of the plug connector and partially arranged on the inner wall of the throttling hole, the present application utilizes the principle that the passing area required for heating is small and the passing area required for cooling is large, and all the throttling surfaces are arranged on the plug connector in sequence, so that half of the plug connector is used for heating and half is used for cooling, thereby improving the flow control accuracy.

[0012] In the above expansion valve, a spring 3 is further provided between the valve core and the spring seat, and under the action of the spring 1, when the two valve cores are against each other, there is a gap between the end of the spring 3 and the adjacent valve core or spring seat, and the starting elastic force value of the spring 2 is greater than the sum of the elastic force values ​​of the spring 1 and the spring 3 when they are compressed to the point where the valve core and the spring seat are against each other. By adding the spring 3, five flow level working modes can be realized for both cooling and heating. Specifically, when the air conditioner is heating, the gaseous refrigerant pushes the valve core with a throttling hole to move, so that the matching surface and the corresponding throttling surface sequentially form corresponding throttling channels for the following heating modes:

[0013] 1 / 4 Heating mode: The valve core compresses a portion of spring 1, but has not yet contacted spring 3;

[0014] Intermediate heating mode: the valve core continues to compress spring 1 until it contacts the end of spring 3;

[0015] Rated heating mode: the valve core continues to compress spring 3 until it abuts against the spring seat;

[0016] Maximum heating mode: the spring seat compresses part of the spring, but has not yet contacted the limit part;

[0017] Super large heating mode: the spring seat continues to compress the second spring until it abuts against the limit part;

[0018] That is, spring one controls the 1 / 4 heating mode and the intermediate heating mode, spring three controls the rated heating mode, and spring two combined with the limit part controls the maximum heating mode and the extra-large heating mode.

[0019] Similarly, when the air conditioner is cooling, the liquid refrigerant pushes the valve core with the plug connector to move, so that the matching surface and the corresponding throttling surface sequentially form corresponding throttling channels for the following cooling modes:

[0020] 1 / 4 cooling mode: the valve core compresses a portion of spring 1, but has not yet contacted spring 3;

[0021] Intermediate cooling mode: The valve core continues to compress spring 1 until it contacts the end of spring 3;

[0022] Rated cooling mode: the valve core continues to compress spring 3 until it abuts against the spring seat;

[0023] Maximum cooling mode: the spring seat compresses part of the spring, but has not yet contacted the limit part;

[0024] Super cooling mode: the spring seat continues to compress the second spring until it abuts against the limit part;

[0025] That is, spring one controls the 1 / 4 cooling mode and the intermediate cooling mode, spring three controls the rated cooling mode, and spring two combined with the limit part controls the maximum cooling mode and the extra-large cooling mode.

[0026] Correspondingly, there are nine throttling surfaces, which are arranged in descending order of diameter along the insertion direction of the plug connector, namely, 1 / 4 heating throttling surface, intermediate heating throttling surface, rated heating throttling surface, maximum heating throttling surface, 1 / 4 cooling throttling surface, intermediate cooling throttling surface, rated cooling throttling surface, maximum cooling throttling surface and super-large cooling throttling surface. Among them, there is no separate super-large heating throttling surface, but the 1 / 4 cooling throttling surface and the intermediate cooling throttling surface are borrowed for the super-large heating mode. Because the refrigerant is gaseous during heating, the throttling channel formed by the matching surface and the 1 / 4 cooling throttling surface and the intermediate cooling throttling surface is sufficient for the passage of gaseous refrigerant required for the super-large heating mode. It can be seen from the above working modes that after setting spring three, ten working modes with different flow levels can be realized, so the flow control accuracy is higher.

[0027] In the above expansion valve, the spring seat is in a straight tube shape, one end of the spring one is inserted into the spring seat, the other end extends out of the spring seat and abuts against the end face of the valve core, one end of the spring three is sleeved on the spring seat, the other end protrudes out of the spring seat end face, and when the two valve cores abut against each other, there is a gap between the end of the spring three protruding out of the spring seat and the adjacent valve core end face. The spring one has the smallest spring coefficient, so it is arranged inside the spring seat, and the spring three is sleeved outside the spring seat, so that the spring three remains stable even when it is not compressed.

[0028] In the above expansion valve, the outer circumferential surface of the spring seat has an annular guide portion in the circumferential direction, and the outer circumferential surface of the guide portion is slidably matched with the circumferential surface of the valve body. One end of the spring three sleeved on the spring seat abuts against the guide portion, and the inner circumferential surface of the spring seat has a constricted portion, and one end of the spring one inserted in the spring seat abuts against the constricted portion. The stability of the movement of the spring seat is ensured by the guide portion, and the stability of the spring one and the spring three is ensured in combination with the constricted portion.

[0029] In the above expansion valve, the limiting part is in a straight cylindrical shape, and the outer peripheral surface of the limiting part has a fixed part in the circumferential direction, the fixed part is fixedly connected to the valve body, the second spring is sleeved on the limiting part, and one end of the second spring abuts on the fixed part, and the other end abuts on the end surface of the spring seat, and when the second spring is compressed, the spring seat can abut on the limiting part. The limiting part is used to limit the spring seat in the super large heating mode and the super large cooling mode to ensure the accuracy of flow control.

[0030] In the above expansion valve, a straight cylindrical guide seat is fixed in the valve body, the inner hole of the guide seat is a stepped hole, one of the valve cores has a guide column, the guide column slides through the guide seat and slides with the inner hole wall of the guide seat with a smaller diameter, the other valve core has a cylindrical portion on its end surface, the cylindrical portion slides into the guide seat and slides with the inner hole wall of the guide seat with a larger diameter, and the plug connector is located at the end of the guide column. The valve core with the plug connector slides with the guide seat through the guide column, and the valve core with the throttling hole slides with the guide seat through the cylindrical portion, so that the two valve cores that need to be sleeved on each other are guided by the same guide seat, thereby ensuring the relative position accuracy and movement accuracy of the two, that is, ensuring the relative position accuracy between the matching surface and the throttling surface, thereby ensuring the flow control accuracy.

[0031] In the above expansion valve, the spring seat is in the shape of a straight cylinder, the end of the valve core is slidably inserted in the spring seat, and the outer circumference of the valve core is slidably matched with the inner circumference of the spring seat. The inner circumference of the spring seat has a step surface in the circumferential direction, and the outer circumference of the insertion end of the valve core has a limiting convex portion. The spring seat is fixed with a limiting member at one end facing the limiting portion, and the spring 1 is arranged in the spring seat, and one end of the spring 1 abuts on the limiting member, and the other end abuts on the end face of the valve core. Under the action of the spring 1, the limiting convex portion abuts against the step surface. This structure inserts the valve core into the spring seat, and the two realize sliding fit, which increases the stability of the valve core, and makes the spring 1 located inside the valve seat, so that the three form an integral module. When the valve core compresses the spring 1, it moves relative to the spring seat, and the spring seat guides the valve core, thereby ensuring the position accuracy.

[0032] An expansion valve comprises a tubular valve body and two valve cores, wherein one valve core is fixed in the valve body, and the other valve core is slidably arranged in the valve body, one valve core has a penetrating throttling hole, and the other valve core has a plug connector on its end face which is columnar and can be inserted into the throttling hole to form a throttling channel, the valve body has a limiting portion, characterized in that the outer circumferential surface of the plug connector and / or the inner circumferential surface of the throttling hole have a plurality of annular throttling surfaces with different diameters along the length direction, a spring seat is slidably arranged between the slidable valve core and the limiting portion, a spring 1 is arranged between the slidable valve core and the spring seat, a spring 2 is arranged between the spring seat and the limiting portion, and the spring 1 and spring 2 have different stiffness coefficients.

[0033] One valve core in the valve body is fixed and the other valve core is slidable, so the refrigerant in the valve body can only flow in one direction for refrigeration, that is, the expansion valve is used for single-cooling air-conditioning equipment. Specifically, when indoor cooling is performed, liquid refrigerant flows into the refrigeration inlet and pushes the valve core, and the valve core compresses the corresponding spring one until the valve core is in contact with the spring seat. In this process, the throttling channel formed by the corresponding throttling surface is used for the intermediate refrigeration mode. The valve core pushes the spring seat so that the spring seat compresses a part of the spring two, but has not yet contacted the limiting part. In this process, the throttling channel formed by the corresponding throttling surface is used for the rated refrigeration mode. The spring seat continues to compress the spring two until it is in contact with the limiting part. In this process, the throttling channel formed by the corresponding throttling surface is used for the maximum refrigeration mode, that is, the structure realizes three flow level working modes of refrigeration, and the three working modes with different flow rates are separately controlled by spring one and spring two, wherein spring one controls one working mode, and spring two combined with the limiting part controls two working modes, so the flow control accuracy is higher.

[0034] In the above expansion valve, the spring coefficient of the first spring is smaller than that of the second spring, and the starting elastic force of the second spring is greater than the elastic force of the first spring when the valve core is compressed to abut against the spring seat. The spring coefficient of the first spring is smaller, so that the valve core compresses the first spring first, and the spring seat can remain stationary, reducing the pressure demand at the refrigeration port in the initial stage of refrigeration, while the starting elastic force of the second spring is larger, so that the second spring remains stationary during the compression of the first spring, avoiding mutual interference and affecting the flow control accuracy.

[0035] In the above expansion valve, there are at least three throttling surfaces and they are all located on the plug connector. The throttling surfaces are arranged in order from large to small according to diameter along the insertion direction of the plug connector. The inner circumference of the throttling hole has an annular mating surface, and a throttling channel is formed between the mating surface and the corresponding throttling surface. In this structure, there are three throttling surfaces, and the diameters are different. When the mating surface is opposite to the corresponding throttling surface, a corresponding throttling channel is formed between the two. Therefore, the larger the diameter of the throttling surface, the smaller the cross-sectional area of ​​the throttling channel. Along the insertion direction of the plug connector, the diameters are arranged from large to small, which are the intermediate refrigeration throttling surface, the rated refrigeration throttling surface, and the maximum refrigeration throttling surface.

[0036] In the above expansion valve, a spring 3 is also provided between the sliding valve core and the spring seat, and under the action of the spring 1, when the two valve cores are against each other, there is a gap between the end of the spring 3 and the adjacent valve core or spring seat, and the starting elastic force value of the spring 2 is greater than the sum of the elastic force values ​​of the spring 1 and the spring 3 when they are compressed to the valve core and the spring seat. By adding the spring 3, the refrigeration can realize five flow level working modes. Specifically, when the air conditioner is refrigerating, the liquid refrigerant pushes the valve core to move, so that the matching surface and the corresponding throttling surface sequentially form corresponding throttling channels for the following refrigeration modes:

[0037] 1 / 4 cooling mode: the valve core compresses a portion of spring 1, but has not yet contacted spring 3;

[0038] Intermediate cooling mode: The valve core continues to compress spring 1 until it contacts the end of spring 3;

[0039] Rated cooling mode: the valve core continues to compress spring 3 until it abuts against the spring seat;

[0040] Maximum cooling mode: the spring seat compresses part of the spring, but has not yet contacted the limit part;

[0041] Super cooling mode: the spring seat continues to compress the second spring until it abuts against the limit part;

[0042] That is, spring one controls the 1 / 4 cooling mode and the intermediate cooling mode, spring three controls the rated cooling mode, and spring two combined with the limit part controls the maximum cooling mode and the extra-large cooling mode.

[0043] Correspondingly, there are five throttling surfaces, which are 1 / 4 refrigeration throttling surface, intermediate refrigeration throttling surface, rated refrigeration throttling surface, maximum refrigeration throttling surface and extra-large refrigeration throttling surface in order from large to small in diameter along the insertion direction of the plug. It can be seen from the above working modes that after setting spring three, five refrigeration working modes with different flow levels can be achieved, so the flow control accuracy is higher.

[0044] In the above expansion valve, the spring seat is in a straight tube shape, one end of the spring one is inserted into the spring seat, the other end extends out of the spring seat and abuts against the end face of the valve core, one end of the spring three is sleeved on the spring seat, the other end protrudes out of the spring seat end face, and when the two valve cores abut against each other, there is a gap between the end of the spring three protruding out of the spring seat and the adjacent valve core end face. The spring one has the smallest spring coefficient, so it is arranged inside the spring seat, and the spring three is sleeved outside the spring seat, so that the spring three remains stable even when it is not compressed.

[0045] Compared with the prior art, this expansion valve has the following advantages:

[0046] 1. Since a slidable spring seat is provided, spring 1, spring 2 and spring 3 can be respectively provided at both ends of the spring seat, and spring 1, spring 2 and spring 3 can work in different time periods, wherein spring 1 controls two working modes, spring 2 controls two working modes, and spring 3 controls one working mode, so that ten working modes with different flow levels can be realized, thereby improving the accuracy of cross-sectional area adjustment of the throttling channel, that is, improving the flow control accuracy.

[0047] 2. Since a straight cylindrical guide seat is fixed in the valve body, the valve core with the plug-in joint slides with the guide seat through the guide column, and the valve core with the throttling hole slides with the guide seat through the cylindrical part, so that the two valve cores that need to be mounted on each other are guided by the same guide seat, thereby ensuring the relative position accuracy of the two, that is, ensuring the relative position accuracy between the matching surface and the throttling surface, thereby ensuring the flow control accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 It is a structural cross-sectional view of the expansion valve.

[0049] Figure 2 yes Figure 1 A magnified view of the structure at center.

[0050] Figure 3 It is a structural cross-sectional view of the expansion valve in the second embodiment.

[0051] Figure 4 yes Figure 3 A magnified view of the structure at point B.

[0052] Figure 5 It is a structural cross-sectional view of a valve core and a spring seat in the third embodiment.

[0053] Figure 6 It is a structural cross-sectional view of another valve core and spring seat in the third embodiment.

[0054] Figure 7 It is a partial structural cross-sectional view of two valve cores in the fourth embodiment.

[0055] Figure 8 It is a structural cross-sectional view of the expansion valve in the fifth embodiment.

[0056] Fig. 9 It is a structural cross-sectional view of the expansion valve in the sixth embodiment.

[0057] Fig.10 It is a structural cross-sectional view of the expansion valve in the seventh embodiment.

[0058] Fig.11 It is a schematic diagram of the structure of the valve core at the plug connector in the seventh embodiment.

[0059] Fig.12 It is a structural cross-sectional view of the expansion valve in the eighth embodiment.

[0060] In the figure, 1, valve body; 11, cooling inlet; 12, heating inlet; 2, valve core; 21, throttling hole; 211, matching surface; 22, plug connector; 221, 1 / 4 heating throttling surface; 222, intermediate heating throttling surface; 223, rated heating throttling surface; 224, maximum heating throttling surface; 225, 1 / 4 cooling throttling surface; 226, intermediate cooling throttling surface; 227, rated cooling throttling surface; 228, maximum cooling throttling surface; 229, extra-large cooling throttling surface; 23, flow hole; 24, guide column; 25, cylindrical part; 26, limiting convex part; 3, limiting part; 31, fixing part; 4, spring seat; 41, guide part; 42, necking part; 43, step surface; 44, limiting member; 5, spring one; 6, spring two; 7, spring three; 8, guide seat; 9, throttling channel. DETAILED DESCRIPTION

[0061] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0062] Embodiment 1:

[0063] like Figure 1 As shown, an expansion valve comprises a tubular valve body 1, the two end ports of the valve body 1 are respectively a heating inlet 12 and a cooling inlet 11, a straight cylindrical limiting portion 3 is fixed at both ends of the valve body 1, two valve cores 2 are slidably arranged between the two limiting portions 3, a straight cylindrical spring seat 4 is slidably arranged between the valve core 2 and the adjacent limiting portion 3, a spring 1 5 is arranged between the valve core 2 and the spring seat 4, a spring 2 6 is arranged between the spring seat 4 and the limiting portion 3, the spring 1 5 has a smaller stiffness coefficient than the spring 2 6, and the starting elastic force value of the spring 2 6 is greater than the elastic force value when the spring 1 5 is compressed to the point where the valve core 2 abuts against the spring seat 4. One of the valve cores 2 is provided with a through throttling hole 21 in the axial direction, and the inner circumferential surface of the throttling hole 21 has a radially protruding and annular mating surface 211, and the end surface of the other valve core 2 has a columnar plug connector 22, combined with Figure 2 As shown, the outer peripheral surface of the plug connector 22 has six annular throttling surfaces with different diameters. Under the action of spring 1 5 and spring 2 6, the plug connector 22 is inserted into the throttling hole 21, and a throttling channel 9 is formed between the matching surface 211 and the opposite throttling surface. The six throttling surfaces are arranged in descending order according to the diameter along the insertion direction of the plug connector 22, and are named as intermediate heating throttling surface 222, rated heating throttling surface 223, maximum heating throttling surface 224, intermediate cooling throttling surface 226, rated cooling throttling surface 227 and maximum cooling throttling surface 228.

[0064] Specifically, the outer circumference of the spring seat 4 has an annular guide portion 41 in the circumferential direction, and the outer circumference of the guide portion 41 is slidably matched with the inner circumference of the valve body 1. The inner circumference of the spring seat 4 has a constricted portion 42. One end of the spring 1 5 is inserted into the spring seat 4 and abuts against the constricted portion 42, and the other end extends out of the spring seat 4 and abuts against the end face of the valve core 2. The limiting portion 3 is in the shape of a straight cylinder, and the outer circumference of the limiting portion 3 has a fixed portion 31 in the circumferential direction. The fixed portion 31 is fixedly connected to the valve body 1. The spring 2 6 is sleeved on the limiting portion 3, and one end of the spring 2 6 abuts against the fixed portion 31, and the other end abuts against the end face of the spring seat 4. When the spring 2 6 is compressed, the spring seat 4 can abut against the limiting portion 3.

[0065] A straight cylindrical guide seat 8 is fixed in the valve body 1, and the inner hole of the guide seat 8 is a three-level stepped hole. A guide column 24 is provided on one of the valve cores 2. The guide column 24 slides through the guide seat 8 and slides with the inner hole wall of the guide seat 8 with the smallest diameter. A cylindrical portion 25 is provided on the end surface of the other valve core 2. The cylindrical portion 25 slides into the guide seat 8 and slides with the inner hole wall of the guide seat 8 with the largest diameter. The plug connector 22 is located at the end of the guide column 24. A flow hole 23 is opened in the axial direction on the guide column 24. One end of the flow hole 23 penetrates to the end surface of the valve core 2, and the other end penetrates to the outer peripheral surface of the guide column 24 and is relatively connected to the inner hole of the guide seat 8. The guide portion 41 is arranged around the throttle hole 21 and is connected to the throttle hole 21.

[0066] When the air conditioner is heating, the gaseous refrigerant flows into the heating inlet 12 of the valve body 1, and the refrigerant pushes the valve core 2 with the throttling hole 21 to move, thereby realizing the following heating working mode:

[0067] Intermediate heating mode: the valve core 2 compresses the corresponding spring 5 until the valve core 2 abuts against the spring seat 4. During this process, the matching surface 211 is opposite to the intermediate heating throttling surface 222 to form a throttling channel 9.

[0068] Rated heating mode: the valve core 2 pushes the spring seat 4, so that the spring seat 4 compresses a part of the spring 2 6, and there is still a gap between the spring seat 4 and the limiting portion 3. In this process, the matching surface 211 is opposite to the rated heating throttling surface 223 and forms a throttling channel 9.

[0069] Maximum heating mode: the spring seat 4 continues to compress the spring 2 6 until it abuts against the limiting portion 3. During this process, the matching surface 211 is opposite to the maximum heating throttling surface 224 and forms a throttling channel 9.

[0070] When the air conditioner is cooling, liquid refrigerant flows into the cooling inlet 11 of the valve body 1, and the refrigerant pushes the valve core 2 with the plug connector 22 to move, thereby realizing the following cooling working mode:

[0071] Intermediate cooling mode: the valve core 2 compresses the corresponding spring 5 until the valve core 2 abuts against the spring seat 4. During this process, the matching surface 211 is opposite to the intermediate cooling throttling surface 226 to form a throttling channel 9.

[0072] Rated cooling mode: the valve core 2 pushes the spring seat 4, so that the spring seat 4 compresses a part of the spring 2 6, and there is still a gap between the spring seat 4 and the limiting portion 3. In this process, the matching surface 211 is opposite to the rated cooling throttling surface 227 and forms a throttling channel 9.

[0073] Maximum cooling mode: the spring seat 4 continues to compress the spring 2 6 until it abuts against the limiting portion 3. During this process, the matching surface 211 is opposite to the maximum cooling throttling surface 228 and forms a throttling channel 9.

[0074] Embodiment 2:

[0075] The structure of the expansion valve is basically the same as that of the first embodiment. Figure 3 As shown, a spring 3 7 is further provided between the valve core 2 and the spring seat 4. One end of the spring 3 7 is sleeved on the spring seat 4 and abuts against the guide portion 41, and the other end protrudes from the end face of the spring seat 4 and has a gap with the opposite end face of the valve core 2. The spring coefficient of the spring 3 7 is greater than the spring coefficient of the spring 1 5, but less than the spring coefficient of the spring 2 6, and the starting elastic force value of the spring 2 6 is greater than the sum of the elastic force values ​​of the spring 1 5 and the spring 3 7 when they are compressed to the point where the valve core 2 abuts against the spring seat 4. Figure 4 As shown, correspondingly, the plug connector 22 has nine throttling surfaces with different diameters, which are arranged in sequence from large to small along the insertion direction of the plug connector 22, and are named 1 / 4 heating throttling surface 221, intermediate heating throttling surface 222, rated heating throttling surface 223, maximum heating throttling surface 224, 1 / 4 cooling throttling surface 225, intermediate cooling throttling surface 226, rated cooling throttling surface 227, maximum cooling throttling surface 228 and extra-large cooling throttling surface 229, among which the extra-large heating throttling surface is not separately provided, but the 1 / 4 cooling throttling surface 225 and the intermediate cooling throttling surface 226 are borrowed for the extra-large heating mode, because the refrigerant is gaseous during heating, and therefore the throttling channel 9 formed by the matching surface 211 and the 1 / 4 cooling throttling surface 225 and the intermediate cooling throttling surface 226 is sufficient for the passage of the gaseous refrigerant required for the extra-large heating mode.

[0076] This structure can realize five flow level working modes for cooling and heating. Specifically, when the air conditioner is heating, the gaseous refrigerant pushes the valve core 2 with a throttling hole 21 to move, thereby realizing the following heating working modes:

[0077] 1 / 4 heating mode: the valve core 2 compresses a part of the spring 1 5, but has not yet contacted the spring 3 7, and there is a gap between the valve core 2 and the end of the spring 3 7. In this process, the matching surface 211 is opposite to the 1 / 4 heating throttling surface 221 and forms a throttling channel 9;

[0078] Intermediate heating mode: the valve core 2 continues to compress the spring 1 5 until it contacts the end of the spring 3 7. During this process, the matching surface 211 is opposite to the intermediate heating throttling surface 222 to form a throttling channel 9;

[0079] Rated heating mode: the valve core 2 continues to compress the spring 3 7 until it abuts against the spring seat 4. During this process, the matching surface 211 is opposite to the rated heating throttling surface 223 and forms a throttling channel 9;

[0080] Maximum heating mode: the spring seat 4 compresses a part of the spring 2 6, but has not yet contacted the limiting portion 3, and there is a gap between the spring seat 4 and the limiting portion 3. In this process, the matching surface 211 is opposite to the maximum heating throttling surface 224 and forms a throttling channel 9;

[0081] Extra-large heating mode: the spring seat 4 continues to compress the spring 2 6 until it abuts against the limiting portion 3. During this process, the matching surface 211 is opposite to the 1 / 4 refrigeration throttling surface 225 and the middle refrigeration throttling surface 226 to form a throttling channel 9.

[0082] That is, spring one 5 controls the 1 / 4 heating mode and the intermediate heating mode, spring three 7 controls the rated heating mode, and spring two 6 combined with the limiter 3 controls the maximum heating mode and the extra-large heating mode.

[0083] When the air conditioner is cooling, the liquid refrigerant pushes the valve core 2 with the plug connector 22 to move, thereby realizing the following cooling working modes:

[0084] 1 / 4 refrigeration mode: the valve core 2 compresses a part of the spring 1 5, but has not yet contacted the spring 3 7, and there is a gap between the valve core 2 and the end of the spring 3 7. In this process, the matching surface 211 is opposite to the 1 / 4 refrigeration throttling surface 225 and forms a throttling channel 9;

[0085] Intermediate cooling mode: the valve core 2 continues to compress the spring 1 5 until it contacts the end of the spring 3 7. During this process, the matching surface 211 is opposite to the intermediate cooling throttling surface 226 to form a throttling channel 9;

[0086] Rated cooling mode: the valve core 2 continues to compress the spring 3 7 until it abuts against the spring seat 4. During this process, the matching surface 211 is opposite to the rated cooling throttling surface 227 and forms a throttling channel 9;

[0087] Maximum cooling mode: the spring seat 4 compresses a part of the spring 2 6, but has not yet contacted the limiting portion 3, and there is a gap between the spring seat 4 and the limiting portion 3. In this process, the matching surface 211 is opposite to the maximum cooling throttling surface 228 and forms a throttling channel 9;

[0088] Super large cooling mode: the spring seat 4 continues to compress the spring 2 6 until it abuts against the limiting portion 3. During this process, the matching surface 211 is opposite to the super large cooling throttling surface 229 and forms a throttling channel 9.

[0089] That is, spring one 5 controls the 1 / 4 cooling mode and the intermediate cooling mode, spring three 7 controls the rated cooling mode, and spring two 6 combined with the limit part 3 controls the maximum cooling mode and the extra-large cooling mode.

[0090] Embodiment three:

[0091] The structure of the expansion valve is basically the same as that of the first embodiment. Figure 5 , Figure 6 As shown, the spring seat 4 is in the shape of a straight cylinder, the end of the valve core 2 is slidably inserted in the spring seat 4, the inner circumferential surface of the spring seat 4 has a step surface 43 in the circumferential direction, the outer circumferential surface of the insertion end of the valve core 2 has a limiting convex portion 26, and a limiting member 44 is fixed to one end of the spring seat 4 facing the limiting portion 3, the limiting member 44 on one spring seat 4 is annular, and the limiting member 44 on the other spring seat 4 is cylindrical, the spring 15 is arranged in the spring seat 4, and one end of the spring 15 abuts against the limiting member 44, and the other end abuts against the end face of the valve core 2, and under the action of the spring 15, the limiting convex portion 26 abuts against the step surface 43.

[0092] Embodiment 4:

[0093] The structure of the expansion valve is basically the same as that of the first embodiment. Figure 7 As shown, the throttling surfaces are all arranged on the hole wall of the throttling hole 21, that is, a 1 / 4 heating throttling surface 221, an intermediate heating throttling surface 222, a rated heating throttling surface 223, a maximum heating throttling surface 224, a 1 / 4 cooling throttling surface 225, an intermediate cooling throttling surface 226, a rated cooling throttling surface 227, a maximum cooling throttling surface 228 and an extra-large cooling throttling surface 229 are arranged in sequence on the hole wall of the throttling hole 21 along the withdrawal direction of the plug connector 22, and the outer peripheral surface of the plug connector 22 is the mating surface 211, and a throttling channel 9 is formed between the two.

[0094] Embodiment five:

[0095] The structure of the expansion valve is basically the same as that of the first embodiment. Figure 8As shown, the valve core 2 with a throttle hole 21 is fixed in the valve body 1, and the valve core 2 with a plug connector 22 is slidably arranged. Correspondingly, there is only one spring 1 5, spring 2 6, spring seat 4 and limit portion 3. The spring seat 4 is located between the sliding valve core 2 and the limit portion 3. Therefore, the refrigerant in the valve body 1 can only flow in one direction for cooling. That is, the expansion valve is used for single-cooling air-conditioning equipment. When indoor cooling is performed, the liquid refrigerant flows into the cooling inlet and pushes the valve core 2. The valve core 2 compresses the corresponding spring 1 5 until the expansion valve is used for cooling. The valve core 2 is in abutment with the spring seat 4. In this process, the throttling channel 9 formed by the corresponding throttling surface is used for the intermediate cooling mode. The valve core 2 pushes the spring seat 4, so that the spring seat 4 compresses a part of the spring 2 6, but has not yet contacted the limit portion 3. In this process, the throttling channel 9 formed by the corresponding throttling surface is used for the rated cooling mode. The spring seat 4 continues to compress the spring 2 6 until it is in abutment with the limit portion 3. In this process, the throttling channel 9 formed by the corresponding throttling surface is used for the maximum cooling mode, that is, this structure realizes the cooling working mode of three flow levels of cooling.

[0096] Embodiment six:

[0097] The structure of the expansion valve is basically the same as that of the fifth embodiment. Fig. 9 As shown, the valve core 2 with the plug connector 22 is fixed in the valve body 1, and the valve core 2 with the throttling hole 21 is slidably arranged in the valve body 1. During operation, the refrigerant pushes the valve core 2 with the throttling hole 21 to perform cooling.

[0098] Embodiment seven:

[0099] The structure of the expansion valve is basically the same as that of the fifth embodiment. Fig.10 As shown, a spring 3 7 is further provided between the sliding valve core 2 and the spring seat 4. One end of the spring 3 7 is sleeved on the spring seat 4 and abuts against the guide portion 41, and the other end protrudes from the end face of the spring seat 4 and has a gap with the opposite end face of the valve core 2. The spring coefficient of the spring 3 7 is greater than the spring coefficient of the spring 1 5, but less than the spring coefficient of the spring 2 6, and the starting elastic force value of the spring 2 6 is greater than the sum of the elastic force values ​​of the spring 1 5 and the spring 3 7 when they are compressed to the point where the valve core 2 abuts against the spring seat 4. Fig.11 As shown, correspondingly, the plug connector 22 has five throttling surfaces with different diameters, which are arranged in order from large to small along the insertion direction of the plug connector 22, and are named as 1 / 4 refrigeration throttling surface 225, intermediate refrigeration throttling surface 226, rated refrigeration throttling surface 227, maximum refrigeration throttling surface 228 and super large refrigeration throttling surface 229. By adding spring 3 7, the refrigeration realizes five flow level working modes. Specifically, when the air conditioner is refrigerating, the liquid refrigerant pushes the valve core 2 to move, so that the matching surface 211 and the corresponding throttling surface sequentially form corresponding throttling channels 9 for the following refrigeration modes:

[0100] 1 / 4 cooling mode: the valve core 2 compresses a part of the spring 1 5, but has not yet contacted the spring 3 7;

[0101] Intermediate cooling mode: the valve core 2 continues to compress the spring 1 5 until it contacts the end of the spring 3 7;

[0102] Rated cooling mode: the valve core 2 continues to compress the spring 3 7 until it abuts against the spring seat 4;

[0103] Maximum cooling mode: the spring seat 4 compresses a portion of the spring 2 6, but has not yet contacted the limiting portion 3;

[0104] Super cooling mode: the spring seat 4 continues to compress the spring 2 6 until it abuts against the limiting portion 3;

[0105] That is, spring one 5 controls the 1 / 4 cooling mode and the intermediate cooling mode, spring three 7 controls the rated cooling mode, and spring two 6 combined with the limit part 3 controls the maximum cooling mode and the extra-large cooling mode.

[0106] Embodiment eight:

[0107] The structure of the expansion valve is basically the same as that of the seventh embodiment. Fig.12 As shown, the valve core 2 with the plug connector 22 is fixed in the valve body 1, and the valve core 2 with the throttling hole 21 is slidably arranged in the valve body 1. During operation, the refrigerant pushes the valve core 2 with the throttling hole 21 to perform cooling.

[0108] The specific embodiments described herein are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

[0109] Although the terms valve body 1, cooling inlet 11, heating inlet 12, etc. are used more frequently in this article, the possibility of using other terms is not excluded. These terms are used only to more conveniently describe and explain the essence of the present invention; interpreting them as any additional restrictions is contrary to the spirit of the present invention.

Claims

1. An expansion valve, comprising a tubular valve body (1) and two valve cores (2) slidably arranged in the valve body (1), wherein the valve body (1) has two limit portions (3), the two valve cores (2) are located between the two limit portions (3), one of the valve cores (2) has a through throttling hole (21), and the other valve core (2) has a plug connector (22) on its end surface which is cylindrical and can be inserted into the throttling hole (21) to form a throttling channel (9), characterized in that: The outer circumference of the plug connector (22) and / or the inner circumference of the throttling hole (21) are provided with a plurality of annular throttling surfaces of different diameters along the length direction; a spring seat (4) is slidably arranged between the valve core (2) and the limiting portion (3) at the same end of the valve body (1); a spring 1 (5) is arranged between the valve core (2) and the spring seat (4); a spring 2 (6) is arranged between the spring seat (4) and the limiting portion (3); the spring 1 (5) and the spring 2 (6) have different spring coefficients; a spring 2 (6) is fixed inside the valve body (1); A straight cylindrical guide seat (8) having an inner hole of a stepped hole, wherein one valve core (2) is provided with a guide column (24), wherein the guide column (24) slides through the guide seat (8) and slides with the hole wall of the guide seat (8) with a smaller diameter, and the other valve core (2) is provided with a cylindrical portion (25) on its end surface, wherein the cylindrical portion (25) slides into the guide seat (8) and slides with the hole wall of the guide seat (8) with a larger diameter, and the plug connector (22) is located at the end of the guide column (24).

2. The expansion valve according to claim 1, characterized in that: The spring coefficient of the spring one (5) is smaller than the spring coefficient of the spring two (6), and the starting elastic force value of the spring two (6) is larger than the elastic force value when the spring one (5) is compressed to the point where the valve core (2) abuts against the spring seat (4).

3. The expansion valve according to claim 2, characterized in that: There are at least six throttling surfaces, all of which are located on the plug connector (22). The throttling surfaces are arranged in order from large to small according to diameter along the insertion direction of the plug connector (22). The inner circumference of the throttling hole (21) has an annular mating surface (211), and a throttling channel (9) is formed between the mating surface (211) and the opposite throttling surface.

4. The expansion valve according to claim 1, 2 or 3, characterized in that: A spring three (7) is also provided between the valve core (2) and the spring seat (4), and under the action of the spring one (5), when the two valve cores (2) abut against each other, a gap is provided between the end of the spring three (7) and the adjacent valve core (2) or the spring seat (4), and the starting elastic force value of the spring two (6) is greater than the sum of the elastic force values ​​of the spring one (5) and the spring three (7) when they are compressed to the point where the valve core (2) abuts against the spring seat (4).

5. The expansion valve according to claim 4, characterized in that: The spring seat (4) is in the shape of a straight cylinder. One end of the spring one (5) is inserted into the spring seat (4), and the other end extends out of the spring seat (4) and abuts against the end face of the valve core (2). One end of the spring three (7) is sleeved on the spring seat (4), and the other end protrudes from the end face of the spring seat (4). When the two valve cores (2) abut against each other, a gap exists between the end of the spring three (7) protruding from the spring seat (4) and the end face of the adjacent valve core (2).

6. The expansion valve according to claim 5, characterized in that: The outer circumferential surface of the spring seat (4) is provided with an annular guide portion (41) in the circumferential direction, and the outer circumferential surface of the guide portion (41) is slidably matched with the inner circumferential surface of the valve body (1). One end of the spring three (7) sleeved on the spring seat (4) abuts against the guide portion (41), and the inner circumferential surface of the spring seat (4) is provided with a constricted portion (42), and one end of the spring one (5) inserted into the spring seat (4) abuts against the constricted portion (42).

7. The expansion valve according to claim 6, characterized in that The limiting portion (3) is in the shape of a straight cylinder, and the outer peripheral surface of the limiting portion (3) has a fixing portion (31) in the circumferential direction, and the fixing portion (31) is fixedly connected to the valve body (1). The second spring (6) is sleeved on the limiting portion (3), and one end of the second spring (6) abuts against the fixing portion (31), and the other end abuts against the end surface of the spring seat (4). When the second spring (6) is compressed, the spring seat (4) can abut against the limiting portion (3).

8. The expansion valve according to claim 1, 2 or 3, characterized in that: The spring seat (4) is in the shape of a straight cylinder, the end of the valve core (2) is slidably inserted into the spring seat (4), and the outer peripheral surface of the valve core (2) is slidably matched with the inner peripheral surface of the spring seat (4).

9. The expansion valve according to claim 8, characterized in that The inner circumferential surface of the spring seat (4) has a step surface (43) in the circumferential direction, the outer circumferential surface of the insertion end of the valve core (2) has a limiting protrusion (26), and a limiting member (44) is fixed to one end of the spring seat (4) facing the limiting member (3). The spring one (5) is arranged in the spring seat (4), and one end of the spring one (5) abuts against the limiting member (44), and the other end abuts against the end surface of the valve core (2). Under the action of the spring one (5), the limiting protrusion (26) abuts against the step surface (43).

10. An expansion valve, comprising a tubular valve body (1) and two valve cores (2), wherein one valve core (2) is fixed in the valve body (1), and the other valve core (2) is slidably arranged in the valve body (1), one valve core (2) has a throttling hole (21) extending therethrough, and the end surface of the other valve core (2) has a plug connector (22) which is columnar and can be inserted into the throttling hole (21) to form a throttling channel (9), the valve body (1) has a limiting portion (3), and is characterized in that: The plug connector (22) has a plurality of annular throttling surfaces with different diameters on the outer circumference surface and / or the inner circumference surface of the throttling hole (21) along the length direction; a spring seat (4) is slidably arranged between the slidably arranged valve core (2) and the limiting portion (3); a spring one (5) is arranged between the slidably arranged valve core (2) and the spring seat (4); a spring two (6) is arranged between the spring seat (4) and the limiting portion (3); the spring one (5) and the spring two (6) have different stiffness coefficients; a spring three (7) is also arranged between the slidably arranged valve core (2) and the spring seat (4); and under the action of the spring one (5), when two valve cores (2) abut against each other, a gap is formed between the end of the spring three (7) and the adjacent valve core (2) or the spring seat (4); and the starting elastic force value of the spring two (6) is greater than the sum of the elastic force values ​​of the spring one (5) and the spring three (7) when they are compressed to the point where the valve core (2) abuts against the spring seat (4).

11. The expansion valve according to claim 10, characterized in that The spring coefficient of the spring one (5) is smaller than the spring coefficient of the spring two (6), and the starting elastic force value of the spring two (6) is larger than the elastic force value when the spring one (5) is compressed to the point where the valve core (2) abuts against the spring seat (4).

12. The expansion valve according to claim 11, characterized in that There are at least three throttling surfaces, all of which are located on the plug connector (22). The throttling surfaces are arranged in order from large to small according to diameter along the insertion direction of the plug connector (22). The inner circumference of the throttling hole (21) has an annular mating surface (211), and a throttling channel (9) is formed between the mating surface (211) and the opposite throttling surface.

13. The expansion valve according to claim 10, 11 or 12, characterized in that: The spring seat (4) is in the shape of a straight cylinder. One end of the spring one (5) is inserted into the spring seat (4), and the other end extends out of the spring seat (4) and abuts against the end face of the valve core (2). One end of the spring three (7) is sleeved on the spring seat (4), and the other end protrudes from the end face of the spring seat (4). When the two valve cores (2) abut against each other, a gap exists between the end of the spring three (7) protruding from the spring seat (4) and the end face of the adjacent valve core (2).

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