Electromagnetic valve and air conditioning system

Abstract

The electromagnetic valve comprises a valve body, a valve needle, a first sealing structure and a second sealing structure, a valve cavity is formed in the valve body, an inlet communicated with the valve cavity is formed in the side wall of the valve body, a valve port section is arranged at the lower end of the side wall of the valve body, and the valve port section is provided with a main valve port communicated with the valve cavity; the valve needle is located in the valve cavity and can move in the vertical direction of the valve cavity so that the inlet and the main valve port can be communicated or separated. The first sealing structure is arranged between the valve body and the valve needle and located at the upper end of the inlet. The second sealing structure is located at the lower end of the inlet and comprises a sealing groove and a sealing ring arranged in the sealing groove, and the sealing groove is formed in the inner wall of the valve port section or the outer wall of the valve needle. According to the technical scheme, the problem that an existing electromagnetic valve is prone to inner leakage is solved, and the electromagnetic valve better in performance and reliability is provided.

Description

Technical Field

[0001] The present invention relates to the technical field of solenoid valves, and particularly to a solenoid valve and an air conditioning system. Background Art

[0002] The seal of the original solenoid valve is formed by a linear sealing surface formed by a plastic washer provided at the valve needle end and the main valve port in the valve body. After the solenoid valve is switched on and off for a long time, pits will be formed on the surface of the sealing gasket, and the pits will deepen as the number of operations of the solenoid valve increases. Also, with different sealing positions each time, the pit marks will be different. Eventually, the internal leakage of the solenoid valve in the valve-closed state will become larger and larger, and finally lead to failure. Summary of the Invention

[0003] The main object of the present invention is to provide a solenoid valve, aiming to solve the problem that the existing solenoid valve is prone to internal leakage, and to provide a solenoid valve with better performance and reliability.

[0004] To achieve the above object, a solenoid valve proposed by the present invention includes: A valve body, a valve cavity is formed in the valve body, an inlet communicating with the valve cavity is formed on the side wall of the valve body, a valve port section is provided at the lower end of the side wall of the valve body, and the valve port section has a main valve port communicating with the valve cavity; and A valve needle, located in the valve cavity and movable along the up-and-down direction of the valve cavity, so as to connect or disconnect the inlet and the main valve port; A first sealing structure, provided between the valve body and the valve needle and located at the upper end of the inlet; and A second sealing structure, located at the lower end of the inlet, the second sealing structure includes a sealing groove and a sealing ring provided in the sealing groove, the sealing groove is provided on the inner wall of the valve port section or the sealing groove is provided on the outer wall of the valve needle.

[0005] Optionally, at least part of the cross-section of the sealing ring is rectangular or D-shaped, and the shape of the sealing ring is adapted to the shape of the sealing groove.

[0006] Optionally, the sealing ring is hydrogenated nitrile rubber.

[0007] Optionally, the radial compression amount of the sealing ring is 0.15 mm - 0.4 mm.

[0008] Optionally, a lubricating coating is provided on the outer peripheral surface of the sealing ring.

[0009] Optionally, the fitting clearance between the inner wall of the valve body and the outer wall of the valve needle is 0.03 mm - 0.1 mm.

[0010] Optionally, the first sealing structure includes a mounting groove provided on the inner wall of the valve body and a sealing member provided in the mounting groove. The mounting groove is located at the upper end of the inlet, and the outer wall of the valve needle and the inner wall of the valve body press against the sealing member to achieve sealing.

[0011] Optionally, the first sealing structure includes a mounting groove provided on the outer wall of the valve needle and a sealing member provided in the mounting groove. The mounting groove is located at the upper end of the inlet, and the outer wall of the valve needle and the inner wall of the valve body press against the sealing member to achieve sealing.

[0012] Optionally, the mounting groove has the same shape as the sealing groove.

[0013] Optionally, the sealing ring and the sealing member have the same shape and / or the same material.

[0014] Optionally, a limiting protrusion is formed by inward convexity on the side wall of the valve body at the lower end of the inlet. The valve needle includes a main body section and a head section having a step with the main body section, and the end face of the step abuts against the limiting protrusion.

[0015] Optionally, the sealing groove and the sealing ring are provided on the valve port section, and the end of the valve needle is provided with a chamfer.

[0016] Optionally, the angle of the chamfer is 10°-20°.

[0017] Optionally, the solenoid valve further includes a coil assembly that drives the valve needle. The coil assembly includes a connecting seat, and the connecting seat is connected to the valve body by laser welding or argon arc welding.

[0018] Optionally, the coil assembly further includes a housing, a lead screw located inside the housing, a support member, and a mounting bearing. The housing is connected to the connecting seat, the lead screw is threadedly connected to the valve needle, the mounting bearing is provided on the connecting seat, the support member is connected to the housing, and both ends of the lead screw are in transmission connection with the support member and the mounting bearing. The lead screw is used to drive the valve needle to move up and down in the valve cavity.

[0019] Optionally, the coil assembly further includes a rotor component located inside the housing. The rotor component is injection molded with inserts and is fixed to the lead screw by laser welding or argon arc welding.

[0020] Optionally, the mounting bearing is riveted and fixed to the connecting seat; or, the connecting seat is provided with a snap ring groove, and the coil assembly further includes a snap ring that is snap-fitted into the snap ring groove to fix the mounting bearing.

[0021] Optionally, the mounting bearing and the lead screw are in interference fit, and the interference amount is 0-0.03 mm.

[0022] Optionally, the support member and the housing are in interference fit, and the interference amount is 0 - 0.05 mm.

[0023] Optionally, the support member is formed by plastic injection molding and is provided with a limiting hole.

[0024] The present invention also provides an air - conditioning system, including the electromagnetic valve as described above.

[0025] In the technical solution of the present invention, by adopting a valve body, a valve needle, a first sealing structure and a second sealing structure, a valve cavity is formed in the valve body, an inlet communicating with the valve cavity is formed on the side wall of the valve body, a valve port section is provided at the lower end of the side wall of the valve body, and the valve port section has a main valve port communicating with the valve cavity; the valve needle is located in the valve cavity and can move in the up - and - down direction of the valve cavity, so as to connect or disconnect the inlet and the main valve port; the first sealing structure is arranged between the valve body and the valve needle and is located at the upper end of the inlet; and is located at the lower end of the inlet. Compared with the hard - contact linear seal between the valve needle and the valve port section, it is easy to wear and generate internal leakage points; or a plastic gasket is provided to solve the wear problem, but the plastic gasket is prone to pits, and finally the internal leakage of the electromagnetic valve will become larger and larger when the valve is in the closed state. In this solution, by adopting a sealing groove and a sealing ring arranged in the sealing groove, the sealing groove is arranged on the inner wall of the valve port section or the sealing groove is arranged on the outer wall of the valve needle, and the outer wall of the valve needle and the inner wall of the valve port section squeeze the sealing ring for sealing. When squeezing the sealing ring, the contact between the sealing ring and the wall surface is surface contact, thus avoiding the situation that the existing electromagnetic valve is prone to internal leakage at the main valve port. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on the structures shown in these drawings.

[0027] Figure 1 It is a schematic structural diagram of an embodiment of the electromagnetic valve of the present invention; Figure 2 is Figure 1 a partial enlarged view of A in Figure 3 is Figure 2 a schematic structural diagram of an embodiment of the valve body in Figure 4 is Figure 2 a schematic structural diagram of an embodiment of the valve needle in Figure 5 is Figure 2Structural schematic diagram of an embodiment of the middle snap ring and the connection seat; Figure 6 Structural schematic diagram of another embodiment of the solenoid valve of the present invention; Figure 7 is Figure 6 Partial enlarged view at B in; Figure 8 Structural schematic diagram of still another embodiment of the solenoid valve of the present invention; Figure 9 is Figure 8 Structural schematic diagram of an embodiment in which the needle body is provided with a sealing groove; Figure 10 Structural schematic diagram of yet another embodiment of the solenoid valve of the present invention; Figure 11 is Figure 10 Structural schematic diagram of an embodiment of the needle body; Figure 12 is Figure 10 Structural schematic diagram of an embodiment of the valve body.

[0028] Explanation of the reference numerals in the drawings:

[0029] The realization, functional features and advantages of the object of the present invention will be further described with reference to the embodiments and the accompanying drawings. Specific embodiments

[0030] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without making creative efforts belong to the scope of protection of the present invention.

[0031] It should be noted that all directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the relative positional relationship and movement conditions between components in a specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly.

[0032] In addition, the descriptions involving "first", "second", etc. in the present invention are for descriptive purposes only, and should not be construed as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions between various embodiments may be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0033] The seal of the original solenoid valve is achieved through the line seal surface formed by the plastic washer provided at the valve needle end and the main valve port in the valve body. After the solenoid valve is switched on and off for a long time, pits will form on the surface of the gasket, and the pits will deepen as the number of operations of the solenoid valve increases. Also, with different sealing positions each time, the pit marks will be different. Eventually, the internal leakage of the solenoid valve in the valve-closed state will become larger and larger, and finally lead to failure.

[0034] Therefore, the present invention proposes a solenoid valve, aiming to solve the problem of internal leakage occurring during the long-term operation of the solenoid valve and providing a solenoid valve with better performance and reliability.

[0035] Refer to Figures 1 to 12 In an embodiment of the present invention, the solenoid valve 10 controls the opening and closing of the valve needle 20 through electromagnetic force, thereby controlling the flow of fluid. The solenoid valve 10 is mainly applied in the control fields of liquids and gases, such as water supply systems, heating systems, air conditioning systems, the automotive industry, etc. When the solenoid valve 10 is applied to an air conditioning system, it can control the flow rate of the refrigerant to ensure proper refrigeration effect. For example, the solenoid valve 10 in an intelligent variable-frequency air conditioner can automatically adjust the refrigerant flow rate according to user needs, thereby improving the energy efficiency of the air conditioner. When the solenoid valve 10 is applied to refrigeration equipment, such as supermarket freezers, ice makers, food processing equipment, etc., all need to use the solenoid valve 10 to control the flow rate of the refrigerant to maintain stable temperature and humidity. When the solenoid valve 10 is applied to a heat pump system, the heat pump utilizes the heat of the external environment to heat or cool the indoor air. In the refrigeration mode, the solenoid valve 10 controls the flow rate of the refrigerant to achieve a reduction in indoor temperature.

[0036] The solenoid valve 10 generally includes the following main components: a coil 11, a valve body 30, a valve needle 20, etc. The coil 11 is an important part of the solenoid valve 10. It is wound by a wire and generates a magnetic force in the magnetic field when electrified. The magnetic field of the coil 11 acts on the piston or the valve needle 20 to control the opening or closing of the valve. The valve body 30 is the outer shell of the solenoid valve 10, usually made of metal or plastic, and contains a space for the valve needle 20 inside. The valve needle 20 is a movable component, which is affected by the magnetic field of the coil 11 to control the opening and closing state of the valve. The solenoid valve 10 usually has an electrical interface for connecting the power supply and the control signal. This enables the solenoid valve 10 to be operated through a control system and perform on-off control as required. The solenoid valve 10 may be equipped with some sensors, such as a temperature sensor, for monitoring the ambient temperature or the temperature of the refrigerant. These sensors provide the necessary feedback signals for the electronic control unit to make corresponding adjustments. Some solutions include springs. Some solenoid valves 10 are designed to use springs to provide a closing force. When the coil 11 is not electrified, the spring will make the valve needle 20 return to the initial position and close the valve.

[0037] Refer to Figure 1, specifically, the solenoid valve 10 includes a main valve port 331, a sealing ring 52, a connecting seat 17, a valve needle 20, a lead screw 15, a mounting bearing 16, a rotor assembly 13, a support member 14, a housing 12, and a coil 11. The support member 14 is fixedly connected to the housing 12 by interference fit; a concave groove is provided in the inner hole of the main valve port 331, and the sealing ring 52 is placed in the groove to seal the first path of the fluid flowing from the valve needle 20 to the main valve port 331; a step is provided in the inner hole at the lower end of the connecting seat 17, and the sealing ring 52 is provided in the step. The main valve port 331 and the connecting seat 17 are press-fitted into the connecting seat 17 by the press-fitting portion of the main valve port 331 and fixedly connected by laser welding or argon arc welding. Here, the sealing ring 52 forms the second sealing path between the valve needle 20 and the connecting seat 17; the valve needle 20 is movably arranged in the main valve port 331 and the connecting seat 17 assembly; the mounting bearing 16 and the lead screw 15 are fixedly connected by the tight fit between the inner cylindrical surface of the mounting bearing 16 and the outer circle of the lead screw 15, and the downward displacement is restricted by the shoulder of the lead screw 15; the lead screw 15 is screwed with the nut assembly; a stepped inner hole at the upper end of the connecting seat 17 positions the mounting bearing 16, and the mounting bearing 16 is fixedly connected in the connecting seat 17 through the riveting portion; the rotor assembly 13 is of a traditional structure, and the limiting plate is nested and injection-molded in the rotor and fixedly connected to the step of the lead screw 15 by laser welding or argon arc welding; the support member 14 is provided with a hollow limiting hole to provide circumferential limitation for the lead screw 15 during operation and ensure coaxiality; the housing 12 is in interference fit with the outer circle of the connecting seat 17 through the inner hole, and then continuous laser welding is carried out to realize the sealing of the solenoid valve 10. By applying an electric pulse with a certain law to the coil 11, the rotor assembly is excited to rotate, thereby driving the lead screw 15 to rotate. During the operation of the lead screw 15, the hollow limiting hole of the support member 14 and the hole of the mounting bearing 16 provide circumferential limitation to ensure the coaxiality during the operation and realize reliable operation.

[0038] A third sealing structure (not marked in the figure) is provided between the inner wall of the valve seat and the outer wall of the valve port section 33. The third sealing structure includes a groove provided on the outer peripheral wall of the valve port section 33 and a sealing ring 52 installed in the groove. Of course, the groove can also be provided on the inner wall of the valve seat.

[0039] A fourth sealing structure (not marked in the figure) is provided between the outer wall of the connecting seat 17 and the inner wall of the valve seat. The fourth sealing structure includes a sealing ring 52 provided between the valve seat and / or the connecting seat 17.

[0040] Refer to Figures 1 to 12, specifically, a valve cavity 31 is formed inside the valve body 30, an inlet 32 communicating with the valve cavity 31 is formed on the side wall of the valve body 30, a valve port section 33 is provided at the lower end of the side wall of the valve body 30, and the valve port section 33 has a main valve port 331 communicating with the valve cavity 31; the valve needle 20 is located inside the valve cavity 31 and can move in the up and down direction of the valve cavity 31, so as to connect or disconnect the inlet 32 and the main valve port 331; a first sealing structure 40 is provided between the valve body 30 and the valve needle 20, at the upper end of the inlet 32, and the first sealing structure 40 is used to seal the gap between the valve needle 20 and the valve body 30 when the solenoid valve 10 is closed, so as to avoid internal leakage of the medium from passing through the position of the first sealing structure 40 from the inlet 32.

[0041] In the traditional solution, the sealing between the valve needle 20 and the main valve port 331 is achieved by the hard contact linear sealing between the valve needle 20 and the main valve port 331. In the case of hard contact, when the valve needle 20 disengages from the main valve port 331, the valve needle 20 rotates, and the valve needle 20 and the main valve port 331 are prone to wear, resulting in leakage points in the linear sealing, which leads to an increase in internal leakage; to solve the wear problem, the existing solution uses a plastic gasket, that is, the plastic gasket provided at the end of the valve needle 20 forms a line sealing surface with the main valve port 331 inside the valve body 30 for sealing, which can solve the wear problem. However, after the solenoid valve 10 is switched on and off for a long time, pits will form on the surface of the sealing gasket, and the pits will deepen as the number of operations of the solenoid valve 10 increases, and the pit marks will also be different with each sealing position. Eventually, the internal leakage of the solenoid valve 10 in the valve-closed state will become larger and larger, and finally lead to failure.

[0042] To solve the problem of internal leakage occurring during the long-term operation of the solenoid valve 10 and provide a solenoid valve 10 with better performance and reliability, in this solution, a second sealing structure 50 is located at the lower end of the inlet 32. The second sealing structure 50 includes a sealing groove 51 and a sealing ring 52 provided in the sealing groove 51. The sealing groove 51 is provided on the inner wall of the valve port section 33 or the sealing groove 51 is provided on the outer wall of the valve needle 20. The outer wall of the valve needle 20 and the inner wall of the valve port section 33 squeeze the sealing ring 52 for sealing, avoiding the situation of easy leakage points in the linear sealing, which leads to an increase in internal leakage.

[0043] The technical solution of the present invention adopts a valve body 30, a valve needle 20, a first sealing structure 40 and a second sealing structure 50. A valve cavity 31 is formed in the valve body 30. An inlet 32 communicating with the valve cavity 31 is formed on the side wall of the valve body 30. A valve port section 33 is provided at the lower end of the side wall of the valve body 30. The valve port section 33 has a main valve port 331 communicating with the valve cavity 31. The valve needle 20 is located in the valve cavity 31 and can move in the up and down direction of the valve cavity 31, so as to connect or disconnect the inlet 32 and the main valve port 331. The first sealing structure 40 is arranged between the valve body 30 and the valve needle 20, at the upper end of the inlet 32; and at the lower end of the inlet 32, compared with the hard contact linear seal between the valve needle 20 and the valve port section 33, it is easy to wear and generate internal leakage points; or a plastic gasket is set to solve the wear problem, but the plastic gasket is prone to pits, and finally the internal leakage of the solenoid valve 10 will become larger and larger when it is in the closed valve state. In this solution, a sealing groove 51 and a sealing ring 52 arranged in the sealing groove 51 are adopted. The sealing groove 51 is arranged on the inner wall of the valve port section 33 or the sealing groove 51 is arranged on the outer wall of the valve needle 20. The outer wall of the valve needle 20 and the inner wall of the valve port section 33 squeeze the sealing ring 52 to seal. When squeezing the sealing ring 52, the contact between the sealing ring 52 and the wall surface is surface contact, which avoids the situation that linear sealing easily leads to an increase in internal leakage.

[0044] Referring to Figure 1 , Figure 2 and Figure 4 Or Figure 8 and Figure 9 , in an embodiment, the sealing groove 51 is arranged on the outer wall of the valve needle 20. In this solution, the installation of the sealing ring 52 is more convenient and the assembly difficulty is lower.

[0045] Referring to Figure 6 and Figure 7 Or Figure 10 and Figure 12 In an embodiment, the sealing groove 51 is arranged on the inner wall of the valve port section 33. The valve needle 20 includes a main body section 21 and a head section 22 having a step with the main body section 21. In this solution, a chamfer can be further provided at the end of the head section 22. Through the chamfer setting of the head section 22, when the valve needle 20 approaches the main valve port 331, the flow regulation function of expansion throttling can be realized by setting different angles of the valve needle 20.

[0046] Specifically, the angle of the chamfer is 10°-20°. According to different angles, the flow rate adjustment function is different. It can be understood that the inclined surface of the chamfer inclines from the outer circumference towards the axis. The larger the inclination angle, the stronger the flow rate adjustment ability. It can be understood that if the valve needle 20 is not provided with a chamfer, or in the solution where the sealing groove 51 is provided on the outer wall of the valve needle 20, when the valve needle 20 moves in the up and down direction of the valve cavity 31, the inlet 32 and the main valve port 331 can be separated. In this process, the valve needle 20 only has a simple closing function and does not have an adjustment function.

[0047] Refer to Figure 8 、 Figure 10 In another embodiment, a limiting protrusion 332 is formed by inwardly protruding the side wall of the valve body 30 at the lower end of the inlet 32. The valve needle 20 includes a main body section 21 and a head section 22 having a step with the main body section 21. The end surface of the step abuts against the limiting protrusion 332. In this way, the stroke of the valve needle 20 can be limited. The step abutting against the edge of the inlet 32 can provide better sealing performance, prevent medium leakage, and can reduce wear and extend the service life of the valve body 30 and the valve needle 20.

[0048] Refer to Figure 1 、 Figure 2 、 Figure 6 And Figure 7 In another embodiment, the valve needle 20 is directly placed in the valve port section 33, which can make the valve body 30 more compact, save space, and can provide a faster response speed and more accurate flow control.

[0049] Regarding the setting of the first sealing structure 40.

[0050] Refer to Figure 1 、 Figure 6 In one embodiment, the first sealing structure 40 includes a mounting groove 41 provided on the inner wall of the valve body 30 and a sealing member 42 provided in the mounting groove 41. The mounting groove 41 is located at the upper end of the inlet 32. The outer wall of the valve needle 20 and the inner wall of the valve body 30 squeeze the sealing member 42 to achieve sealing.

[0051] Refer to Figure 8 、 Figure 10 In another embodiment, the first sealing structure 40 includes a mounting groove 41 provided on the outer wall of the valve needle 20 and a sealing member 42 provided in the mounting groove 41. The mounting groove 41 is located at the upper end of the inlet 32. The outer wall of the valve needle 20 and the inner wall of the valve body 30 squeeze the sealing member 42 to achieve sealing.

[0052] Furthermore, in the traditional solution, the valve needle 20 is movably arranged within the connecting seat 17 component of the main valve port 331; by applying electrical pulses with a certain pattern to the coil 11, the rotor assembly is excited to rotate, thereby driving the screw rod 15 to rotate, and further driving the valve needle 20 to move in the up and down direction of the valve cavity 31. During this process, the rotation of the valve needle 20 may cause the sealing ring 52 to flip or twist, resulting in sealing failure. Therefore, this solution also improves the sealing ring 52. Refer to Figures 1 to 12 , at least a part of the cross-section of the sealing ring 52 is rectangular or D-shaped, and the shape of the sealing ring 52 is adapted to that of the sealing groove 51. In this way, the straight edge of the rectangular part or D-shaped part of the sealing ring 52 abuts against the groove wall of the sealing groove 51, restricting the rotation of the sealing ring 52, thereby avoiding the problem of the sealing ring 52 failing due to flipping or twisting.

[0053] It should be noted that the first sealing structure 40 and the second sealing structure 50 can both adopt the sealing ring 52 in the above form. That is, the shape of the installation groove 41 is the same as that of the sealing groove 51; or, the shape of the installation groove 41 is the same as that of the sealing groove 51 and they are made of the same material.

[0054] Specifically, the sealing ring 52 is made of hydrogenated nitrile rubber. Compared with other materials, the hydrogenated nitrile rubber sealing ring 52 can be used in high-temperature environments up to above 150 °C and maintain good elasticity and durability. The hydrogenated nitrile rubber sealing ring 52 can work in various organic medium environments such as various oils and solvents and will not lose its sealing performance due to the influence of the medium. The hydrogenated nitrile rubber sealing ring 52 can also maintain good performance and long-term durability in an oxidation environment. The hydrogenated nitrile rubber sealing ring 52 has good wear resistance and can be used in high-frequency and high-speed movements without losing its sealing performance due to wear. To ensure the sealing effect between the valve needle 20 and the valve body 30 and facilitate the movement of the valve needle 20, a lubricating coating is provided on the outer peripheral surface of the sealing ring 52. A coating is provided on the surface of the sealing ring 52 to reduce friction and better achieve the sealing of the first sealing structure 40 and the second sealing structure 50.

[0055] Specifically, to ensure the sealing effect, the radial compression amount of the sealing ring 52 is 0.15 mm - 0.4 mm. In this way, after the outer wall of the valve needle 20 and the inner wall of the valve body 30 squeeze the sealing ring 52, it will not get stuck due to the compression amount being greater than 0.4 mm and insufficient power, nor will the sealing effect be poor because it is less than 0.15 mm, and the medium will break through the first sealing structure 40 or the second sealing structure 50 under the action of pressure.

[0056] Specifically, the fitting clearance between the inner wall of the valve body 30 and the outer wall of the valve needle 20 is 0.03 mm - 0.1 mm. If it is less than 0.03 mm, the accuracy required during the operation of the valve needle 20 is high. Otherwise, it is prone to wear and generate abnormal noise, damaging the valve needle 20. If it is greater than 0.1 mm, the cost of the corresponding sealing structure increases, and the sealing effect weakens.

[0057] Further, the solenoid valve 10 further includes a coil 11 assembly that drives the valve needle 20. The coil 11 assembly includes a connection seat 17, and the connection seat 17 is laser welded or argon arc welded to the valve body 30. In this way, compared with the traditional riveting fixation method, the sealing performance is better.

[0058] Further, the coil 11 assembly further includes a housing 12, a lead screw 15 located inside the housing 12, a limit plate, and a mounting bearing 16. The housing 12 is connected to the connection seat 17. The lead screw 15 is threadedly connected to the valve needle 20. The mounting bearing 16 is provided on the connection seat 17, the limit plate is connected to the housing 12, and both ends of the lead screw 15 are drivingly connected to the limit plate and the mounting bearing 16. The lead screw 15 is used to drive the valve needle 20 to move up and down in the valve cavity 31.

[0059] Further, the coil 11 assembly further includes a rotor component 13 located inside the housing 12. The rotor component 13 and the limit plate are injection molded with inserts and are fixed to the lead screw 15 by laser welding or argon arc welding.

[0060] In one embodiment, the mounting bearing 16 is riveted and fixed to the connection seat 17.

[0061] In another embodiment, the connection seat 17 is provided with a circlip 18 groove. The coil 11 assembly further includes a circlip 18, and the circlip 18 is snap-fitted into the circlip 18 groove to fix the mounting bearing 16.

[0062] Specifically, the mounting bearing 16 and the lead screw 15 are in interference fit, and the interference amount is 0 - 0.03 mm.

[0063] Specifically, the support member 14 and the housing 12 are in interference fit, and the interference amount is 0 - 0.05 mm.

[0064] Specifically, the support member 14 is injection molded from plastic and is provided with a limit hole.

[0065] Specifically, the lead screw 15 and the valve needle 20 are screwed together by threads; a stepped inner hole is provided at the upper end of the connecting seat 17 to position and install the bearing 16, and the installed bearing 16 is fixedly connected within the connecting seat 17 by riveting; the rotor component 13 has a traditional structure, with the limiting plate nested and injection-molded within the rotor and fixedly connected to the stepped portion of the lead screw 15 by laser welding or argon arc welding; the support member 14 is provided with a hollow limiting hole to provide circumferential limitation for the lead screw 15 during operation, ensuring coaxiality; the housing 12 is in interference fit with the outer circle of the connecting seat 17 through the inner hole, and then continuous laser welding is performed to achieve the sealing of the solenoid valve 10.

[0066] By applying an electric pulse with a certain pattern to the coil 11, the rotor assembly is excited to rotate, thereby driving the rotation of the lead screw 15. During the operation of the lead screw 15, the hollow limiting hole of the support member 14 and the hole of the installed bearing 16 provide circumferential limitation, ensuring coaxiality during operation and achieving reliable operation. The rotation of the lead screw 15 drives the valve needle 20 to move up and down through the thread pair, realizing the opening and closing of the valve needle 20 relative to the main valve port 331. During the opening and closing process, the second sealing channel between the valve needle 20 and the connecting seat 17 is sealed by the D-shaped imitation seal ring 52. During the closing process, the first seal between the valve needle 20 and the main valve port 331 is sealed by the D-shaped imitation seal ring 52 provided within the main valve port 331. Finally, the on-off and sealing of the solenoid valve 10 are realized.

[0067] In addition, as described above, in the solution where the sealing groove 51 and the seal ring 52 are provided in the valve port section 33, chamfers with different angles can also be provided at the end of the valve needle 20. During the opening and closing process of the solenoid valve 10, the function of expansion throttling can also be realized to achieve flow regulation, thus realizing both the function of the solenoid valve 10 and the function of the expansion valve.

[0068] The solenoid valve 10 in the traditional solution has a two-stage pilot structure. By energizing the electromagnetic coil 11, the static iron core of the armature component is attracted, and the piston component within the main valve moves upward under the action of the pressure difference to achieve the opening and closing of the solenoid valve 10. When the electromagnetic coil 11 is de-energized, the armature component returns to its original position under the action of the spring, and the piston component within the main valve moves downward under the action of the pressure difference to achieve the closing of the solenoid valve 10. Therefore, it can be seen that both the opening and closing of the original solenoid valve 10 require a pressure difference to be formed between the upper and lower ends of the piston component to achieve the opening and closing of the main valve port 331, and the refrigerant medium flow direction of the solenoid valve 10 can only be unidirectional and cannot achieve bidirectional flow. Reverse flow will directly push open the piston component. The sealing of the original solenoid valve 10 is achieved by the linear sealing surface formed by the plastic washer riveted at the lower end of the piston component and the main valve port 331 within the valve seat 1. After the solenoid valve 10 is switched on and off for a long time, pits will form on the surface of the sealing gasket, and the pits will deepen as the number of operations of the solenoid valve 10 increases. Also, due to the different sealing positions each time, the pit marks will be different. Eventually, the internal leakage of the solenoid valve 10 in the valve closing state will become larger and larger, eventually leading to failure.

[0069] The solenoid valve 10 of the present invention effectively avoids the above problems. In the solenoid valve 10 of the present invention, the valve needle 20 is located within the valve cavity 31 and can move in the vertical direction of the valve cavity 31, enabling the communication or disconnection between the inlet 32 and the main valve port 331. Switching can be achieved without the need for a pressure difference, and the action is reliable and sensitive. The refrigerant medium can flow bidirectionally, greatly simplifying the thermal management system. By providing a D-shaped or rectangular sealing ring 52 and applying a coating on the surface layer of the sealing ring 52 to reduce the frictional resistance, the sealing of the first sealing structure 40 and the second sealing structure 50 is realized, avoiding the problems of flipping or twisting of the sealing ring 52, and achieving nearly zero leakage.

[0070] The present invention also provides an air conditioning system, which includes the solenoid valve 10. The specific structure of this air conditioning system refers to the above embodiments. Since the solenoid valve 10 adopts all the technical solutions of the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be elaborated here one by one. This air conditioning system can be used in automobiles or air conditioners.

[0071] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention. Any equivalent structural transformation made under the concept of the present invention using the content of the specification and drawings of the present invention, or any direct / indirect application in other related technical fields, is included in the patent protection scope of the present invention.

Claims

1. An electromagnetic valve, characterized in that, Comprising: A valve body, a valve cavity is formed inside the valve body, an inlet communicating with the valve cavity is formed on the side wall of the valve body, a valve port section is provided at the lower end of the side wall of the valve body, and the valve port section has a main valve port communicating with the valve cavity; and A valve needle, located inside the valve cavity, and capable of moving in the up and down direction of the valve cavity, so as to connect or disconnect the inlet and the main valve port; A first sealing structure, provided between the valve body and the valve needle, and located at the upper end of the inlet; and A second sealing structure, located at the lower end of the inlet, the second sealing structure includes a sealing groove and a sealing ring provided in the sealing groove, the sealing groove is provided on the inner wall of the valve port section or the sealing groove is provided on the outer wall of the valve needle.

2. The electromagnetic valve according to claim 1, characterized in that, At least part of the cross section of the sealing ring is rectangular or D-shaped, and the shape of the sealing ring is adapted to the shape of the sealing groove.

3. The electromagnetic valve according to claim 1, characterized in that, The sealing ring is hydrogenated nitrile rubber.

4. The electromagnetic valve according to claim 1, characterized in that, The radial compression amount of the sealing ring is 0.15 mm - 0.4 mm.

5. The electromagnetic valve according to claim 1, characterized in that, A lubricating coating is provided on the outer peripheral surface of the sealing ring.

6. The electromagnetic valve according to claim 1, characterized in that, The fitting clearance between the inner wall of the valve body and the outer wall of the valve needle is 0.03 mm - 0.1 mm.

7. The electromagnetic valve according to claim 1, characterized in that, The first sealing structure includes a mounting groove provided on the inner wall of the valve body and a sealing member provided in the mounting groove, the mounting groove is located at the upper end of the inlet, and the outer wall of the valve needle and the inner wall of the valve body squeeze the sealing member to be sealed.

8. The electromagnetic valve according to claim 1, characterized in that, The first sealing structure includes a mounting groove provided on the outer wall of the valve needle and a sealing member provided in the mounting groove, the mounting groove is located at the upper end of the inlet, and the outer wall of the valve needle and the inner wall of the valve body squeeze the sealing member to be sealed.

9. The electromagnetic valve according to claim 7 or 8, characterized in that, The mounting groove has the same shape as the sealing groove; and / or, the sealing ring and the sealing member are of the same shape and / or the same material.

10. The electromagnetic valve according to claim 1, characterized in that, A limiting protrusion is convexly provided inward on the side wall of the valve body at the lower end of the inlet, the valve needle includes a main body section and a head section having a step formed with the main body section, and the end face of the step abuts against the limiting protrusion.

11. The electromagnetic valve according to claim 1, characterized in that, The sealing groove and the sealing ring are provided on the valve port section, and a chamfer is provided at the end of the valve needle.

12. The electromagnetic valve according to claim 11, characterized in that, The angle of the chamfer is 10° - 20°.

13. The electromagnetic valve according to claim 1, characterized in that, The solenoid valve further includes a coil assembly, the coil assembly drives the valve needle, the coil assembly includes a connecting seat, and the connecting seat is laser welded or argon arc welded to the valve body.

14. The electromagnetic valve according to claim 13, characterized in that, The coil assembly further includes a housing, a lead screw, a support member and a mounting bearing located inside the housing, the housing is connected to the connecting seat, the lead screw is threadedly connected to the valve needle, the mounting bearing is provided on the connecting seat, the support member is connected to the housing, and both ends of the lead screw are in transmission connection with the support member and the mounting bearing, and the lead screw is used to drive the valve needle to move up and down in the valve cavity.

15. The electromagnetic valve according to claim 14, characterized in that, The coil assembly further includes a rotor component located inside the housing, the rotor component is injection molded with inserts and is fixed to the lead screw by laser welding or argon arc welding.

16. The electromagnetic valve according to claim 14, characterized in that, The mounting bearing is riveted and fixed to the connecting seat; or, the connecting seat is provided with a snap ring groove, the coil assembly further includes a snap ring, and the snap ring is snap-fitted in the snap ring groove to fix the mounting bearing.

17. The electromagnetic valve according to claim 14, characterized in that, The installed bearing and the lead screw are in interference fit, and the interference amount is 0 - 0.03 mm; and / or, the support member and the housing are in interference fit, and the interference amount is 0 - 0.05 mm; and / or, the support member is formed by plastic injection molding and is provided with a limiting hole.

18. An air conditioning system, characterized in that, It includes the solenoid valve according to any one of claims 1 to 17.

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