Valve needle assembly, electromagnetic valve and air conditioning system

Abstract

The invention discloses a valve needle assembly, an electromagnetic valve and an air conditioning system.The valve needle assembly comprises a nut assembly and a needle body assembly, the nut assembly comprises a main body part and limiting parts arranged on the two sides of the main body part, the needle body assembly is connected with the nut assembly, and parts of the limiting parts protrude out of the periphery of the needle body assembly. According to the technical scheme, the machining efficiency of the valve needle can be improved, and then the machining cost of the valve needle is reduced.

Description

Technical Field

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

[0002] In a solenoid valve, a valve needle moves up and down driven by a lead screw to open / close the passage of the valve body. In order to ensure strength and fitting accuracy, the existing valve needle is integrally formed by metal machining, with large machining allowances for cutting and milling, resulting in high machining costs. Summary of the Invention

[0003] The main object of the present invention is to provide a valve needle assembly, aiming to improve the machining efficiency of the valve needle and thereby reduce the machining cost of the valve needle.

[0004] To achieve the above object, a valve needle assembly proposed by the present invention is used for a solenoid valve. The valve needle assembly includes: A nut assembly, the nut assembly includes a main body portion and limiting portions provided on both sides of the main body portion; and A needle body assembly, the needle body assembly is connected to the nut assembly, and a part of the limiting portion protrudes from the outer periphery of the needle body assembly.

[0005] Optionally, a receiving cavity is formed by inward depression at the end of the needle body assembly, and the main body portion is placed in the receiving cavity.

[0006] Optionally, the needle body assembly is provided with a hollow hole, the diameter of the receiving cavity is larger than the diameter of the hollow hole and is communicated with the hollow hole, and the threaded hole of the nut assembly corresponds to and communicates with the hollow hole.

[0007] Optionally, the needle body assembly is provided with a riveting member, the limiting portion is provided with a riveting opening, the riveting member passes through the riveting opening, and the limiting portion abuts against the inner wall of the receiving cavity.

[0008] Optionally, the riveting member is a riveting rib formed by upward convexity at the edge of the opening of the receiving cavity.

[0009] Optionally, two spaced mounting grooves are formed by downward depression at the edge of the opening of the receiving cavity, the riveting member is formed between the two mounting grooves, the limiting portion is located in the mounting groove, and the upper surface of the main body portion is flush with the edge of the opening of the receiving cavity.

[0010] Optionally, the clearance range between the outer peripheral wall of the main body portion and the inner cavity wall of the receiving cavity is 0 - 0.05 mm.

[0011] Optionally, the clearance range between the outer surface of the riveting member and the inner wall of the riveting opening is 0.1 mm - 0.3 mm.

[0012] Optionally, an installation notch is provided at the edge of the cavity opening of the accommodation cavity, the limiting portion is placed in the installation notch, and the limiting portion is welded to the needle body assembly.

[0013] Optionally, an avoidance hole is provided on the limiting portion, and the main body portion has a threaded hole, and the avoidance hole is communicated with the threaded hole.

[0014] Optionally, an air passing hole is provided on the portion of the limiting portion protruding from the outer periphery of the main body portion.

[0015] Optionally, the limiting portion is located at the middle part of the main body portion in the axial direction.

[0016] Optionally, the main body portion and the limiting portion are formed by insert injection molding, the main body portion is made of plastic, and the limiting portion is made of metal.

[0017] Optionally, a first ventilation groove is formed by recessing the outer peripheral wall of the main body portion, and the first ventilation groove penetrates the main body portion along the height direction of the main body portion.

[0018] Optionally, there are a plurality of the first ventilation grooves, and two of the first ventilation grooves are communicated with the riveting interface.

[0019] Optionally, a second ventilation groove is formed by recessing the bottom of the main body portion, and the second ventilation groove penetrates the main body portion.

[0020] Optionally, the first ventilation groove and the second ventilation groove are communicated with each other.

[0021] Optionally, the cross-sectional shapes of the first ventilation groove and the second ventilation groove are circular or triangular or trapezoidal or rectangular.

[0022] Optionally, the diameters of the first ventilation groove and the second ventilation groove are ≥0.5 mm.

[0023] Optionally, the nut assembly is integrally injection molded.

[0024] The present invention also provides a solenoid valve, including the valve needle assembly as described above.

[0025] The present invention also provides an air conditioning system, including the solenoid valve as described above.

[0026] The technical solution of the present invention is to rivet the needle body assembly and the nut assembly. Compared with the traditional solution where the needle body assembly and the nut assembly are integrally formed by metal machining, resulting in large machining allowances for cutting and milling and high processing costs, the valve needle assembly of this solution effectively avoids the above problems. The valve needle assembly is divided into a needle body assembly and a nut assembly, and the needle body assembly and the nut assembly can be processed separately, thereby reducing the cutting machining allowance and processing cost. The nut assembly includes a main body portion and limiting portions provided on both sides of the main body portion. A part of the limiting portion protrudes from the outer periphery of the needle body assembly. Compared with the existing solution where the needle body assembly rotates up / down following the nut assembly during opening / closing, that is, the valve needle assembly rotates up / down, in this solution, the protruding part of the limiting portion cooperates with the valve body, and the limiting portion restricts the valve needle assembly from rotating in the circumferential direction. Thus, the valve needle assembly only moves up and down and does not rotate, reducing the interference with the sealing ring between the valve body and the valve needle assembly and reducing the problem that the sealing ring follows the rotation of the valve needle assembly up / down and flips, resulting in a reduction in sealing ability. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] 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 drawings in the following description 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.

[0028] Figure 1 It is a schematic structural diagram of an embodiment of the solenoid valve of the present invention; Figure 2 is Figure 1 a partial enlarged view of part A in; Figure 3 It is a schematic structural diagram of an embodiment of the valve needle assembly of the present invention; Figure 4 is Figure 3 a sectional structural diagram taken along line A-A in; Figure 5 is Figure 3 a schematic structural diagram of an embodiment of the needle body assembly in; Figure 6 is Figure 3 a schematic structural diagram of an embodiment of the nut assembly in; Figure 7 It is a schematic structural diagram of another embodiment of the valve needle assembly of the present invention; Figure 8 is Figure 7 a sectional structural diagram of; Figure 9 is Figure 7 a schematic structural diagram of another embodiment of the needle body assembly in; Figure 10 is Figure 7 a schematic structural view of another embodiment of the nut assembly in Figure 11 a schematic structural view of yet another embodiment of the valve needle assembly of the present invention; Figure 12 is Figure 11 a schematic cross-sectional structural view of the valve needle assembly in Figure 13 is Figure 12 a schematic structural view of yet another embodiment of the nut assembly in Figure 14 is Figure 13 a schematic structural view of the cross-section and the limiting portion of the nut assembly in

[0029] Explanation of the reference numerals in the drawings:

[0030] The realization of the object of the present invention, functional features and advantages will be further described in conjunction with the embodiments with reference to the drawings. Specific embodiments

[0031] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the 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 of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the protection scope of the present invention.

[0032] 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 drawings). If this specific posture changes, the directional indications will also change accordingly.

[0033] In addition, the descriptions involving "first", "second", etc. in the present invention are only for descriptive purposes, and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between various embodiments can 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 is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope required by the present invention.

[0034] In a solenoid valve, the valve needle moves up and down driven by a lead screw to open / close the passage of the valve body. In order to ensure strength and mating accuracy, the existing valve needle is integrally machined from metal, resulting in large machining allowances for cutting and milling, and high machining costs.

[0035] Therefore, the present invention proposes a valve needle assembly, aiming to improve the machining efficiency of the valve needle and thus reduce the machining cost of the valve needle.

[0036] Refer to Figure 1 and Figure 2 As shown in FIGS. and, the valve needle assembly 20 includes a nut assembly 22 and a needle body assembly 21. The nut assembly 22 includes a main body portion 221 and limiting portions 224 provided on both sides of the main body portion 221. The needle body assembly 21 is connected to the nut assembly 22, and part of the limiting portion 224 protrudes from the outer periphery of the needle body assembly 21. By dividing the valve needle assembly 20 into the needle body assembly 21 and the nut assembly 22, the needle body assembly 21 and the nut assembly 22 can be machined separately, thereby reducing the cutting machining allowance and the machining cost. And compared with the existing solution where the needle body assembly 21 rotates up / down following the nut assembly 22 during opening / closing, that is, the valve needle assembly 20 rotates up / down, in this solution, the protruding part of the limiting portion 224 cooperates with the valve body 11, and the limiting portion 224 restricts the valve needle assembly 20 from rotating circumferentially. Thus, the valve needle assembly 20 only moves up and down without rotating, reducing the interference with the sealing ring 12 between the valve body 11 and the valve needle assembly 20, and reducing the problem that the sealing ring 12 follows the valve needle assembly 20 to rotate up / down and flip, resulting in a reduction in sealing ability.

[0037] Refer to Figures 3 to 10 As shown in FIG., in an embodiment of the present invention, the valve needle assembly 20 includes: a nut assembly 22 and a needle body assembly 21, and the needle body assembly 21 is riveted to the nut assembly 22.

[0038] Refer to Figures 11 to 14 As shown in FIG., in an embodiment of the present invention, the valve needle assembly 20 includes: a nut assembly 22 and a needle body assembly 21, and the needle body assembly 21 is welded to the threaded assembly 22.

[0039] The valve needle assembly 20 is used for the solenoid valve 10. The solenoid valve 10 controls the opening and closing of the valve core through electromagnetic force, thereby controlling the flow of fluids. 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 in an air conditioning system, it can control the refrigerant flow rate 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 in refrigeration equipment, such as supermarket freezers, ice makers, food processing equipment, etc., all need to use the solenoid valve 10 to control the refrigerant flow rate to maintain stable temperature and humidity. When the solenoid valve 10 is applied in 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 refrigerant flow rate to achieve a reduction in indoor temperature.

[0040] The solenoid valve 10 generally includes the following main components: a coil 19, a valve body 11, a valve core, etc. The coil 19 is an important component in the solenoid valve 10. It is wound with a wire and generates a magnetic force in a magnetic field when energized. The magnetic field of the coil 19 acts on the piston or the valve core to control the opening or closing of the valve. The valve body 11 is the outer shell of the solenoid valve 10, usually made of metal or plastic, and contains the space for the valve core inside. The valve core is a movable component that is affected by the magnetic field of the coil 19 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 control signals. This enables the solenoid valve 10 to be operated through a control system and perform on-off control as needed. The solenoid valve 10 may be equipped with some sensors, such as temperature sensors, 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 the closing force. When the coil 19 is de-energized, the spring will return the valve core to the initial position to close the valve.

[0041] Refer to Figure 1, specifically, the solenoid valve 10 includes a valve port, a sealing ring 12, a connecting seat 13, a valve needle assembly 20, a lead screw 14, a bearing 15, a rotor component 16, a support member 17, a housing 18, and a coil 19. The support member 17 is fixedly connected to the housing 18 by interference fit; an inwardly concave groove is provided in the inner hole of the valve port, and the sealing ring 12 is placed in the groove to seal the first path of the fluid flowing from the valve needle to the valve port; a step is provided in the inner hole at the lower end of the connecting seat 13, and the sealing ring 12 is provided in the step. The valve port and the connecting seat 13 are press-fitted into the connecting seat 13 by the press-fitting portion of the valve port and are fixedly connected by laser welding or argon arc welding. Here, the sealing ring 12 forms the second path for sealing between the valve needle and the connecting seat 13; the valve needle component is movably (only movable up and down and not rotatable) arranged within the valve port connecting seat 13 component; the bearing 15 and the lead screw 14 are fixedly connected by the tight fit between the inner cylindrical surface of the bearing 15 and the outer circle of the lead screw 14, and the downward displacement is restricted by the shoulder of the lead screw 14; the lead screw 14 is screwed with the nut assembly 22; a step inner hole at the upper end of the connecting seat 13 positions the bearing 15, and the bearing 15 is fixedly connected within the connecting seat 13 through the riveting portion; the rotor component 16 is of a traditional structure, and the limiting plate is nested and injection-molded within the rotor and is fixedly connected to the step of the lead screw 14 by laser welding or argon arc welding; the support member 17 is provided with a hollow limiting hole to provide circumferential limitation for the lead screw 14 during operation and ensure coaxiality; the housing 18 is in interference fit with the outer circle of the connecting seat 13 through the inner hole, and then continuous laser welding is performed to achieve the sealing of the solenoid valve 10. By applying an electric pulse with a certain pattern to the coil 19, the rotor assembly is excited to rotate, thereby driving the lead screw 14 to rotate. During the operation of the lead screw 14, the circumferential limitation is given by the hollow limiting hole of the support member 17 and the hole of the bearing 15 to ensure the coaxiality during the operation and achieve reliable operation.

[0042] In the technical solution of the present invention, by riveting the needle body assembly 21 and the nut assembly 22, compared with the traditional solution where the needle body assembly 21 and the nut assembly 22 are integrally formed by metal machining, resulting in large machining allowances for cutting and milling and high processing costs, the valve needle assembly 20 of this solution well avoids the above problems. The valve needle assembly 20 is divided into the needle body assembly 21 and the nut assembly 22, and the needle body assembly 21 and the nut assembly 22 can be processed separately, thereby reducing the cutting machining allowance and the processing cost.

[0043] In one embodiment, the nut assembly 22 has a threaded hole 226 in the middle, which can cooperate with the lead screw 14 of the solenoid valve 10. The nut assembly 22 and the needle body assembly 21 can be two concentrically arranged parts. For example, the splicing surface is the same cross-section, with a riveting piece provided on one of them and a riveting port 225 provided on the other, thereby realizing the riveting of the nut assembly 22 and the needle body assembly 21.

[0044] In another embodiment, the needle body assembly 21 is sleeved with the nut assembly 22 and riveted through a riveting portion, which can be a protruding riveting strip, a riveting piece, a flanging, etc.

[0045] Referring to Figures 2 to 10 , in another embodiment, a receiving cavity 212 is formed by inwardly recessing the end of the needle body assembly 21. The nut assembly 22 includes a main body portion 221 and a limiting portion 224 extending from the main body portion 221 to both sides. The main body portion 221 is placed in the receiving cavity 212, and a part of the limiting portion 224 protrudes from the outer periphery of the needle body assembly 21. In this solution, the receiving cavity 212 is machined on the needle body assembly 21, and the main body portion 221 of the threaded component is placed in the receiving cavity 212, which can reduce the overall length of the valve needle assembly 20 and is beneficial to the miniaturization of the product; at the same time, because the nut assembly 22 is located inside the needle body assembly 21, the exposed part of the valve needle assembly 20 can be reduced, improving the safety and service life of the valve needle assembly 20.

[0046] Furthermore, in order to prevent the rotation of the needle body assembly 21 and ensure the closing effect of the needle body assembly 21, a part of the limiting portion 224 protrudes from the outer periphery of the needle body assembly 21. By making a part of the limiting portion 224 of the nut assembly 22 protrude from the outer periphery of the needle body assembly 21, the protruding limiting portion 224 cooperates with the valve body 11, which can prevent the valve needle assembly 20 from rotating when following the lead screw 14, and the valve needle moves in a non-rotating up-and-down motion, thereby improving the stability and reliability of the valve needle assembly 20.

[0047] Furthermore, the needle body assembly 21 is provided with a hollow hole 211. The diameter of the receiving cavity 212 is larger than the diameter of the hollow hole 211 and is connected to the hollow hole 211. The threaded hole 226 of the nut assembly 22 corresponds to and communicates with the hollow hole 211. The needle body assembly 21 is hollow, the diameter of the receiving cavity 212 is larger than the diameter of the hollow hole 211, the nut assembly 22 is placed in the receiving cavity 212, and the threaded hole 226 of the nut assembly 22 is connected to the hollow hole 211. Thus, when the lead screw 14 rotates and the nut assembly 22 moves up and down along the lead screw 14 assembly, the lead screw 14 can extend into the hollow hole 211.

[0048] Specifically, the needle body assembly 21 is provided with a riveting member 213, and the limiting portion 224 is provided with a riveting opening 225. The riveting member 213 passes through the riveting opening 225, and the limiting portion 224 abuts against the cavity wall of the receiving cavity 212.

[0049] Referring to Figures 3 to 6 , in one embodiment, the riveting member 213 is a riveting rib 214 formed by upwardly protruding the edge of the cavity opening of the receiving cavity 212. After the riveting opening 225 of the limiting convex portion passes through the riveting rib 214, it abuts against the edge of the cavity opening of the receiving cavity 212. A part of the main body portion 221 is located in the receiving cavity 212 and is riveted to the limiting portion 224 through the riveting rib 214.

[0050] Referring to Figures 7 to 10 , in another embodiment, two spaced-apart mounting grooves 215 are formed by downward depression at the edge of the orifice of the receiving cavity 212. A riveting member 213 is formed between the two mounting grooves 215. The limiting portion 224 is located inside the mounting. The upper surface of the main body portion 221 is flush with the edge of the orifice of the receiving cavity 212. It can be understood that being flush should be understood as being approximately flush, rather than absolutely flush. An error within 2 mm should be regarded as being flush.

[0051] Two spaced-apart mounting grooves 215 are formed by downward depression at the edge of the orifice of the receiving cavity 212. A riveting member 213 is formed between the two mounting grooves 215. A riveting opening 225 is formed on the limiting portion 224 of the riveting member 213. The edge of the riveting opening 225 is located within the two mounting grooves 215. In this way, the main body portion 221 can be placed inside the receiving cavity 212, and the upper surface of the main body portion 221 is flush with the edge of the orifice of the receiving cavity 212, resulting in better integrity. In addition, since both the limiting portion 224 of the riveting member 213 and the edge of the riveting opening 225 are located within the mounting grooves 215, the riveting member 213 is more secure, avoiding possible loosening or detachment problems during use.

[0052] Furthermore, the clearance range between the outer peripheral wall of the main body portion 221 and the inner cavity wall of the receiving cavity 212 is 0 - 0.05 mm. This clearance size can prevent excessive frictional force from being generated between the main body portion 221 and the inner cavity wall of the receiving cavity 212. At the same time, this clearance size can also effectively prevent excessive vibration from being generated between the main body portion 221 and the inner cavity wall of the receiving cavity 212, thus ensuring the stability of the main body portion 221. In addition, since the clearance range between the outer peripheral wall of the main body portion 221 and the inner cavity wall of the receiving cavity 212 is 0 - 0.05 mm, dust or moisture in the air can be isolated from entering this clearance to a certain extent, and there is a certain fastening effect between the main body portion 221 and the receiving cavity 212, and the nut assembly 22 is not easily detached from the needle assembly 21.

[0053] Further, the clearance range between the outer surface of the riveting part 213 and the inner wall of the riveting opening 225 is 0.1 mm - 0.3 mm. The clearance range between the outer surface of the riveting part 213 and the inner wall of the riveting opening 225 is between 0.1 mm and 0.3 mm. This tiny clearance not only ensures the firmness of riveting but also prevents the riveting part 213 from deforming due to excessive pressure, thus ensuring the quality and performance of the product. Within this clearance range, the contact area between the riveting part 213 and the riveting opening 225 is moderate, neither too large nor too small, ensuring the firmness of the riveting part 213 and the quality of the product. It should be noted that if the clearance range is less than 0.1 mm, it is difficult to dock the riveting part 213 and the riveting opening 225. Similarly, if the clearance range is greater than 0.3 mm, it may lead to insecure riveting, thus affecting the quality and performance of the product as well.

[0054] Referring to Figures 11 to 14 , in the embodiment where the needle body assembly 21 is welded to the threaded component 22.

[0055] Specifically, an installation notch 216 is provided at the edge of the cavity opening of the accommodation cavity 212, the limiting part 224 is placed in the installation notch 216, and the limiting part 224 is welded to the needle body assembly 21. The main body part 221 is placed in the accommodation cavity 212, and the limiting part 224 is placed in the installation notch 216, which is equivalent to internally arranging the threaded component 22 in the needle body assembly 21, with better integrity and smaller overall dimensions.

[0056] Specifically, the main body part 221 and the limiting part 224 are formed by insert injection molding. The main body part 221 is made of plastic material, and the limiting part 224 is made of metal material.

[0057] Specifically, an avoidance hole 227 is provided on the limiting part 224, and the main body part 221 has a threaded hole 226. The avoidance hole 227 is communicated with the threaded hole 226, and the avoidance hole 227 is larger than the threaded hole 226, so as to avoid affecting the cooperation between the nut assembly 22 and the lead screw 14.

[0058] Specifically, the part of the limiting part 224 protruding from the outer periphery of the main body part 221 is provided with an air passing hole 228. The setting of the air passing hole 228 can, on the one hand, reduce the weight, and on the other hand, be communicated with the ventilation groove below.

[0059] Specifically, the limiting part 224 is located at the middle part of the axial direction of the main body part 221, so as to better control the outer surface of the nut assembly 22 to be flush with the outer surface of the needle body assembly 21.

[0060] Referring to Figures 3 to 10, Further, in order to reduce the pressure difference of the switching valve needle assembly 20 and improve the valve opening ability. In one embodiment, a first ventilation groove 222 is formed by recessing the outer peripheral wall of the main body portion 221, and the first ventilation groove 222 penetrates the main body portion 221 along the height direction of the main body portion 221.

[0061] In another embodiment, there are multiple first ventilation grooves 222, and two of the first ventilation grooves 222 communicate with the riveting interface 225.

[0062] In another embodiment, a second ventilation groove 223 is formed by recessing the bottom of the main body portion 221, and the second ventilation groove 223 penetrates the main body portion 221 along the width direction of the main body portion 221.

[0063] In another embodiment, the first ventilation groove 222 and the second ventilation groove 223 communicate with each other.

[0064] In another embodiment, there are two second ventilation grooves 223 that cross each other in a cross shape at the bottom of the nut assembly 22, and there are four first ventilation grooves 222 on the side wall of the main body portion 221. The four first ventilation grooves 222 communicate with the second ventilation groove 223. In this way, when the valve needle and the nut assembly 22 work in the solenoid valve 10, a vertical channel for balancing gas will be formed. Compared with the traditional solution where the balance hole is generally arranged in the slender lead screw 14, which is formed by milling one side of the thread of the lead screw 14 and matching it with the nut hole, the lead screw 14 is prone to deformation, resulting in a decrease in driving coaxiality and easy jamming. In addition, milling the lead screw 14 into a D-shaped edge is likely to generate burrs and bring them into the system, which is also likely to cause jamming and failure.

[0065] Specifically, the cross-sectional shapes of the first ventilation groove 222 and the second ventilation groove 223 are circular or triangular or trapezoidal or rectangular.

[0066] Further, in order to ensure reducing the pressure difference of the switching valve needle assembly 20 and improving the valve opening ability, the diameters of the first ventilation groove 222 and the second ventilation groove 223 are ≥0.5 mm. Although increasing the first ventilation groove 222 and the second ventilation groove 223 can improve the valve opening ability, it can be understood that the first ventilation groove 222 and the second ventilation groove 223 should not be too large, such as larger than the radius of the nut assembly 22, so as to reduce the mass of the nut assembly 22.

[0067] Refer to Figure 6 and Figure 10, Further, the internal thread of the valve needle is screwed and matched with the external thread of the lead screw 14. During the operation of the solenoid valve 10, it is prone to wear, resulting in wear powder in the valve or entering the air-conditioning system, causing jamming and failure. To solve this problem, in one embodiment, the nut assembly 22 is integrally injection-molded. In another embodiment, the limiting portion 224 is formed by flat stamping. The limiting portion 224 is flat-shaped. The nut is made of plastic PPS and fiberglass material, and is integrally injection-molded by inlaying the partition board.

[0068] The present invention also provides a solenoid valve 10, which includes a valve needle assembly 20. The specific structure of the valve needle assembly 20 refers to the above embodiments. Since this solenoid valve 10 adopts all the technical solutions of the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be elaborated here one by one.

[0069] The present invention also provides an air-conditioning system including the solenoid valve 10. This air-conditioning system can be used in vehicles. Since this air-conditioning system adopts all the technical solutions of the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be elaborated here one by one.

[0070] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent structural transformation made by using the description and drawings of the present invention under the concept of the present invention, or direct / indirect application in other related technical fields, is included in the patent protection scope of the present invention.

Claims

1. A valve needle assembly for an electromagnetic valve, characterized in that, The valve needle assembly includes: a nut assembly, the nut assembly including a main body portion and limiting portions provided on both sides of the main body portion; and a needle body assembly, the needle body assembly being connected to the nut assembly, and part of the limiting portion protruding from the outer periphery of the needle body assembly.

2. The valve needle assembly according to claim 1, characterized in that, An accommodation cavity is formed by inward depression at the end of the needle body assembly, and the main body portion is placed in the accommodation cavity.

3. The valve needle assembly according to claim 2, characterized in that, The needle body assembly is provided with a hollow hole, the diameter of the accommodation cavity is larger than the diameter of the hollow hole and is in communication with the hollow hole, and the threaded hole of the nut assembly corresponds to and communicates with the hollow hole.

4. The valve needle assembly according to claim 2 or 3, characterized in that, The needle body assembly is provided with a riveting member, the limiting portion is provided with a riveting opening, the riveting member passes through the riveting opening, and the limiting portion abuts against the inner wall of the accommodation cavity.

5. The valve needle assembly according to claim 4, characterized in that, The riveting member is a riveting rib formed by upward convexity at the edge of the opening of the accommodation cavity.

6. The valve needle assembly according to claim 4, characterized in that, Two spaced mounting grooves are formed by downward depression at the edge of the opening of the accommodation cavity, the riveting member is formed between the two mounting grooves, the limiting portion is located in the mounting groove, and the upper surface of the main body portion is flush with the edge of the opening of the accommodation cavity.

7. The valve needle assembly according to claim 4, characterized in that, The gap range between the outer peripheral wall of the main body portion and the inner cavity wall of the accommodation cavity is 0 - 0.05 mm.

8. The valve needle assembly according to claim 4, characterized in that, The gap range between the outer surface of the riveting member and the inner wall of the riveting opening is 0.1 mm - 0.3 mm.

9. The valve needle assembly according to claim 2 or 3, characterized in that, An installation notch is provided at the edge of the opening of the accommodation cavity, the limiting portion is placed in the installation notch, and the limiting portion is welded to the needle body assembly.

10. The valve needle assembly according to claim 9, characterized in that, A relief hole is provided on the limiting portion, the main body portion has a threaded hole, and the relief hole communicates with the threaded hole; and / or, an air passage hole is provided in the part of the limiting portion protruding from the outer periphery of the main body portion; and / or, the limiting portion is located at the middle part of the main body portion in the axial direction.

11. The valve needle assembly according to claim 10, characterized in that, The main body portion and the limiting portion are formed by insert injection molding, the main body portion is made of plastic material, and the limiting portion is made of metal material.

12. The valve needle assembly according to claim 1, characterized in that, A first ventilation groove is formed by depression on the outer peripheral wall of the main body portion, and the first ventilation groove penetrates the main body portion along the height direction of the main body portion.

13. The valve needle assembly according to claim 12, characterized in that, A second ventilation groove is formed by depression at the bottom of the main body portion, and the second ventilation groove penetrates the main body portion.

14. The valve needle assembly according to claim 13, characterized in that, The first ventilation groove and the second ventilation groove communicate with each other.

15. The valve needle assembly according to claim 13, characterized in that, The cross-sectional shapes of the first ventilation groove and the second ventilation groove are circular or triangular or trapezoidal or rectangular.

16. The valve needle assembly according to claim 13, characterized in that, The diameters of the first ventilation groove and the second ventilation groove are ≥ 0.5 mm.

17. An electromagnetic valve, characterized in that, It includes the valve needle assembly according to any one of claims 1 to 16.

18. An air conditioning system, characterized in that, It includes the solenoid valve according to claim 17.

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