WO2012109993A1

WO2012109993A1 - Electrical expansion valve

Info

Publication number: WO2012109993A1
Application number: PCT/CN2012/071210
Authority: WO
Inventors: 沈自成; 舒小辉
Original assignee: 浙江三花股份有限公司
Priority date: 2011-02-17
Filing date: 2012-02-16
Publication date: 2012-08-23

Abstract

Disclosed is an electrical expansion valve comprising a drive mechanism, a transmission mechanism, a valve seat and a valve pin component; the valve pin component has a valve pin and a valve stem movable along the axial direction of a valve chamber of the electrical expansion valve so as to control the opening size of the valve opening, and has a returning flexible component; the electrical expansion valve also includes a stopping structure arranged in the valve chamber and having an axial channel, and the valve pin component has a lateral flange; the stopping structure is situated above the flange when the valve pin component is moved upwards to a position where the valve opening is at the maximum opening size, and the minimum radial dimension of the axial channel is smaller than the maximum radial dimension of the flange. When the valve pin of the electrical expansion valve is moved upwards to or above the position where the valve opening is at its maximum size, it will not be able to be moved up any further due to the restriction of the stopping structure, thus when the valve pin component needs to be separated from the other upper components for conducting disassembly and replacement of a coil or other operations, the valve pin component will not move up by a large amount to compress the returning flexible component excessively, so that the service life of the flexible component is extended.

Description

一种电子膨胀阀 Electronic expansion valve

本申请要求于 2011 年 02 月 17 日提交中国专利局、申请号为 201110040455.2、发明名称为"一种电子膨胀阀", 以及于 2011年 05月 18 日提交中国专利局、申请号为 201110129451.1、发明名称为"一种电子膨胀阀"的中国专利申请的优先权，其全部内容通过引用结合在本申请中。技术领域 This application is submitted to the Chinese Patent Office on February 17, 2011, the application number is 201110040455.2, the invention name is "an electronic expansion valve", and was submitted to the Chinese Patent Office on May 18, 2011, application number 201110129451.1, invention The priority of the Chinese Patent Application, which is incorporated herein by reference in its entirety in its entirety, the entire entire entire entire entire entire entire entire entire entire entire disclosure Technical field

本发明涉及暖通空调技术领域，特别涉及一种电子膨胀阀。 The invention relates to the technical field of HVAC, and in particular to an electronic expansion valve.

背景技术 Background technique

电子膨胀阀广泛应用于流体的节流膨胀和流量调节。 Electronic expansion valves are widely used for throttling expansion and flow regulation of fluids.

请参考图 1 , 图 1为一种典型的变频空调用减速式电子膨胀阀的结构示意图。 Please refer to Fig. 1. Fig. 1 is a schematic view showing the structure of a typical variable speed electronic expansion valve for inverter air conditioner.

该电子膨胀阀主要包括永磁式步进电机 1、具有三级减速的齿轮减速器 2、位于螺母 4中的丝杆 5和螺纹副结构 3 , 位于阀座 8内的衬套 6、复位弹性部件 7以及阀针部件 9等核心部件。具体工作原理如下：由空调系器 2转动，螺纹副结构 3将该转动转化成丝杆 5的轴向运动，当施加关阀脉冲时，转子逆时针旋转，经过螺纹副结构 3传递，丝杆 5向下运动，顶住传力部件衬套 6, 衬套 6抵住阀针部件 9的上端使其向下运动，此时，复位弹性部件 Ί处于不断拉伸状态，阀针部件 9的端部逐渐封住阀口 10, 即阀口 10的开口度随着阀针部件 9的向下运动逐渐减小；当施加开阀脉冲时，转子顺时针旋转，丝杆 5向上运动，阀针部件 9不受衬套 6的向下抵触力，则阀针部件 9在复位弹性部件 7的回复弹力和***压力作用下将不断向上运动，阀口 10的开启度又逐渐增大。因此，电子膨长阀阀口 10的开启程度得以改变，使得通流面积发生变化，从而达到控制流量，调节过热度的目的。 The electronic expansion valve mainly comprises a permanent magnet type stepping motor 1, a gear reducer with three stages of deceleration, a screw rod 5 located in the nut 4, and a thread pair structure 3, a bushing 6 located in the valve seat 8, and a reduction elasticity A core member such as the member 7 and the valve needle member 9. The specific working principle is as follows: The air conditioner system 2 rotates, and the thread sub-structure 3 converts the rotation into the axial movement of the screw rod 5. When the valve closing pulse is applied, the rotor rotates counterclockwise, and is transmitted through the thread pair structure 3, the screw rod 5 moves downward, against the force-transmitting member bushing 6, and the bushing 6 abuts against the upper end of the valve needle member 9 to move downward. At this time, the return elastic member Ί is in a continuously stretched state, the end of the valve needle member 9 The portion gradually seals the valve port 10, that is, the opening degree of the valve port 10 gradually decreases with the downward movement of the needle member 9; when the valve opening pulse is applied, the rotor rotates clockwise, the screw rod 5 moves upward, and the valve needle member 9 Without the downward contact force of the bushing 6, the valve needle member 9 will continuously move upward under the return elastic force of the return elastic member 7 and the system pressure, and the opening degree of the valve port 10 is gradually increased. Therefore, the degree of opening of the valve port 10 of the electronic expansion valve is changed, so that the flow area is changed, thereby controlling the flow rate and adjusting the degree of heat.

当步进电机 1的线圈出现问题，进行更换时，需要将阀体和线圈进行分离，分离后衬套 6的顶部不与丝杆 5抵接，阀针部件 9向上的移动不再受限制，而此时，制冷剂管路的***压力较大，则在***压力作用下，阀针部件 9会迅速且大幅地向上移动，因此，阀针部件 9在上移过程中会导致复位弹性部件 7过度压缩，丧失或降低其复位能力，从而影响复位弹性部件 7的使用寿命。 When there is a problem with the coil of the stepping motor 1, when the replacement is performed, the valve body and the coil need to be separated, and the top of the bushing 6 is not abutted against the lead screw 5, and the upward movement of the valve needle member 9 is no longer restricted. At this time, the system pressure of the refrigerant line is large, and under the action of the system pressure, the valve The needle member 9 moves up quickly and substantially, so that the valve needle member 9 causes the return elastic member 7 to be excessively compressed during the upward movement, losing or reducing its resetting ability, thereby affecting the service life of the return elastic member 7.

因此，如何使维修时，电子膨胀阀阀针部件的上移高度能够得到一定的限制，从而延长复位弹性部件的使用寿命，是本领域技术人员需要解决的技术问题。发明内容 Therefore, how to make the upward movement height of the valve member of the electronic expansion valve can be restricted to a certain extent, thereby prolonging the service life of the return elastic member, is a technical problem to be solved by those skilled in the art. Summary of the invention

本发明的目的为提供一种电子膨胀阀，该电子膨胀阀阀针部件的上移高度能够得到一定的限制，可以延长复位弹性部件的使用寿命。 SUMMARY OF THE INVENTION An object of the present invention is to provide an electronic expansion valve in which the upward movement height of the valve member can be limited to extend the service life of the return elastic member.

为解决上述技术问题，本发明提供一种电子膨胀阀，包括驱动机构、传动机构、阀座和阀针部件；所述阀针部件具有沿电子膨胀阀阀腔轴向移动以控制阀口开度大小的阀针和阀杆，以及随所述阀针上下移动而缩回或拉伸的复位弹性部件，其特征在于，所述电子膨胀阀还包括设置于所述阀腔中且具有轴向通道的限位结构，所述阀针部件具有横向凸缘；所述限位结构位于所述阀针部件上移至所述阀口刚处于最大开度时所述凸缘的上方，且所述轴向通道的径向最小尺寸小于所述凸缘的径向最大尺寸。 In order to solve the above technical problems, the present invention provides an electronic expansion valve including a driving mechanism, a transmission mechanism, a valve seat and a valve needle member; the valve needle member has an axial movement along the valve chamber of the electronic expansion valve to control the valve opening degree a valve needle and a valve stem of a size, and a return elastic member retracted or stretched as the valve needle moves up and down, wherein the electronic expansion valve further includes a valve disposed in the valve chamber and having an axial passage Limiting structure, the valve needle member has a lateral flange; the limiting structure is located on the valve needle member and moved to the upper side of the flange when the valve port is just at the maximum opening degree, and the shaft The radial minimum dimension to the channel is less than the radial maximum dimension of the flange.

优选地，所述阀针的最大外径大于所述阀杆的直径，所述凸缘为所述阀针。 Preferably, the maximum outer diameter of the valve needle is greater than the diameter of the valve stem, and the flange is the valve needle.

优选地，所述限位结构为具有中心孔的挡圈，所述挡圈的外周与所述阀腔的内壁定位，所述中心孔为所述轴向通道。 Preferably, the limiting structure is a retaining ring having a central hole, an outer circumference of the retaining ring is positioned with an inner wall of the valve cavity, and the central hole is the axial passage.

优选地，所述阀针横截面的外周大致为方形，所述中心孔大致为方形，所述中心孔的边长大于所述阀针外周的边长并小于所述阀针外周的最大对角线长度。 Preferably, the outer circumference of the cross section of the valve needle is substantially square, the central hole is substantially square, the side length of the central hole is larger than the side length of the outer circumference of the valve needle and smaller than the maximum diagonal of the outer circumference of the valve needle Line length.

优选地，所述阀针横截面的外周大致为矩形，所述中心孔大致为矩形，所述中心孔的长度大于所述阀针外周的长度，所述中心孔的宽度大于所述阀针外周的宽度，且所述中心孔的宽度小于所述阀针外周的最大对角线长度。 Preferably, the outer circumference of the cross section of the valve needle is substantially rectangular, the central hole is substantially rectangular, the length of the central hole is greater than the length of the outer circumference of the valve needle, and the width of the central hole is larger than the outer circumference of the valve needle The width of the central aperture is less than the maximum diagonal length of the outer circumference of the valve needle.

优选地，所述阀座的内壁具有与所述挡圈的外周适配的环形凹槽，且所述挡圈具有沿径向延伸的开口。 Preferably, the inner wall of the valve seat has an annular groove adapted to the outer circumference of the retaining ring, and The retaining ring has an opening that extends in a radial direction.

优选地，所述挡圈的外周大致为圓形。优选地，当所述阀针部件上移至所述阀口处于最大开度时，所述限位结构与所述凸缘之间的轴向距离小于 lmm„ Preferably, the outer circumference of the retaining ring is substantially circular. Preferably, when the valve needle member is moved up to the maximum opening of the valve port, the axial distance between the limiting structure and the flange is less than lmm.

优选地，当所述阀针部件上移至所述阀口处于最大开度时，所述限位结构与所述凸缘之间的轴向距离在 0.2mm-lmm之间。 Preferably, when the valve needle member is moved up to the valve opening to be at the maximum opening degree, the axial distance between the limiting structure and the flange is between 0.2 mm and 1 mm.

优选地，所述弹性部件为波纹管。 Preferably, the elastic member is a bellows.

该电子膨胀阀的阀腔中设有限位结构，则阀针部件上移至阀口最大时的位置处或略高于此位置时，会由于限位结构的抵触而无法继续上移，则阀针部件的上端部即使不与其他部件抵触，也无法上移，因此，当进行线圈拆换或其他需要使阀针部件与上方其他部件分离时，阀针部件不会在系统压力下大幅上移，从而避免波纹管类复位弹性部件的过度压缩，延长复位弹性部件的使用寿命；且限位结构位于阀口处于最大开度时凸缘的上方，因此，限位结构在限制阀针部件上移时，不会影响阀针部件对阀口开度大小的控制。 The electronic expansion valve has a limiting structure in the valve cavity, and when the valve needle member is moved to the position at the maximum position of the valve port or slightly higher than the position, the valve can not continue to move up due to the resistance of the limiting structure, then the valve The upper end of the needle member cannot move up even if it does not interfere with other components. Therefore, when the coil is replaced or if the needle member needs to be separated from the other components above, the needle member does not move up significantly under system pressure. Therefore, the excessive compression of the bellows type return elastic member is avoided, and the service life of the return elastic member is prolonged; and the limit structure is located above the flange when the valve port is at the maximum opening degree, therefore, the limit structure moves on the restriction valve needle member When it does not affect the control of the valve stem opening to the size of the valve opening.

为解决上述技术问题，本发明还提供一种电子膨胀阀，包括阀座、沿阀腔轴向移动的阀杆，以及随所述阀杆移动而伸缩的复位弹性部件，所述复位弹性部件的上端通过定位部件定位于阀体上，所述阀腔中设有限位部件，所述阀腔的内壁具有径向凸台，所述限位部件置于所述凸台上，且所述限位部件具有供所述阀杆贯穿的轴向通道；所述阀杆上具有位于所述轴向通道下方的径向凸缘，所述轴向通道的径向最小尺寸小于所述凸缘的径向最大尺寸；所述阀腔中还设有支撑件，所述支撑件支撑于所述限位部件和所述定位部件之间。 In order to solve the above technical problem, the present invention also provides an electronic expansion valve including a valve seat, a valve stem that moves axially along the valve cavity, and a return elastic member that retracts and contracts as the valve stem moves, the reset elastic member The upper end is positioned on the valve body by a positioning component, the valve cavity is provided with a limiting component, the inner wall of the valve cavity has a radial boss, the limiting component is placed on the boss, and the limit is The component has an axial passage for the valve stem to penetrate; the valve stem has a radial flange below the axial passage, the radial minimum dimension of the axial passage being smaller than the radial direction of the flange The maximum size; the valve cavity is further provided with a support member, and the support member is supported between the limiting member and the positioning member.

优选地，所述限位部件为具有中心孔的挡圈，所述支撑件为外套所述复位弹性部件的套筒。 Preferably, the limiting member is a retaining ring having a central bore, and the support member is a sleeve that covers the resilient member.

优选地，所述套筒为圓筒状，所述套筒置入所述阀腔后，所述套筒的侧壁抵靠所述阀腔的内壁。 Preferably, the sleeve is cylindrical, and after the sleeve is placed in the valve cavity, the side wall of the sleeve abuts against the inner wall of the valve chamber.

优选地，所述挡圈具有连通其内周壁和外周壁的开口，且开口的轴向高度为所述挡圈的轴向高度。优选地，所述阀杆末端的阀针为所述凸缘。 Preferably, the retaining ring has an opening communicating with the inner peripheral wall and the outer peripheral wall thereof, and the axial height of the opening is the axial height of the retaining ring. Preferably, the valve needle at the end of the valve stem is the flange.

优选地，所述中心孔的形状为圓形，所述中心孔的直径小于所述阀针的最大外径。 Preferably, the central hole has a circular shape, and the central hole has a diameter smaller than a maximum outer diameter of the valve needle.

优选地，当所述阀针部件上移至所述阀口处于最大开度时，所述挡圈与所述凸缘之间的轴向距离小于 2mm。 Preferably, when the valve needle member is moved up to the maximum opening of the valve port, the axial distance between the retaining ring and the flange is less than 2 mm.

优选地，当所述阀针部件上移至所述阀口处于最大开度时，所述挡圈与所述凸缘之间的轴向距离在 0.2mm-lmm之间。 Preferably, when the valve needle member is moved up to the maximum opening of the valve port, the axial distance between the retaining ring and the flange is between 0.2 mm and 1 mm.

该电子膨胀阀，其阀腔中设有限位部件，限位部件具有供阀杆贯穿的轴向通道，阀杆上具有位于轴向通道下方的凸缘，且凸缘的径向最小尺寸大于轴向通道的径向最大尺寸，同时，限位部件在支撑件的作用下与阀体之间形成轴向定位，则阀杆上移至一定程度时，凸缘会受限位部件的限制而无法继续上移，则阀杆即使不与其他部件抵触，也无法上移。因此，当进行线圈拆换或其他需要使阀针部件与上方其他部件分离时，阀杆不会在 ***压力下大幅上移，从而避免波纹管类复位弹性部件的过度压缩，延长复位弹性部件的使用寿命；此外，限位部件依靠位于径向凸台和定位部件之间的支撑件进行定位，则限位部件和支撑件在装配时，置于径向凸台上即可，操作工序简单。 The electronic expansion valve has a limiting component in the valve cavity, the limiting component has an axial passage for the valve stem to penetrate, the valve stem has a flange below the axial passage, and the radial minimum dimension of the flange is larger than the shaft The radial maximum dimension of the channel, and at the same time, the limiting member forms an axial positioning between the valve body and the valve body. When the valve stem is moved up to a certain extent, the flange may be limited by the positional component. If you continue to move up, the valve stem will not move up even if it does not interfere with other parts. Therefore, when coil replacement or other need to separate the valve needle member from other components above, the valve stem will not move up significantly under system pressure, thereby avoiding excessive compression of the bellows type return elastic member and prolonging the reset elastic member. Service life; In addition, the limiting member is positioned by the support member located between the radial boss and the positioning member, and the limiting member and the supporting member are placed on the radial boss during assembly, and the operation process is simple.

附图说明 DRAWINGS

图 1为一种典型的变频空调用减速式电子膨胀阀的结构示意图；图 2为本发明所提供电子膨胀阀第一种具体实施方式的结构示意图；图 3为本发明所提供电子膨胀阀中阀针部件的结构示意图； 1 is a schematic structural view of a typical variable speed electronic expansion valve for an inverter air conditioner; FIG. 2 is a schematic structural view of a first embodiment of an electronic expansion valve according to the present invention; FIG. 3 is an electronic expansion valve provided by the present invention. Schematic diagram of the valve needle member;

图 4为图 3中阀针上端的横截面示意图； Figure 4 is a schematic cross-sectional view of the upper end of the valve needle of Figure 3;

图 5为图 2中挡圈的结构示意图； Figure 5 is a schematic structural view of the retaining ring of Figure 2;

图 6为图 2中挡圈的另一种结构示意图； Figure 6 is a schematic view showing another structure of the retaining ring of Figure 2;

图 7为图 2中挡圈的又一种结构示意图； Figure 7 is a schematic view showing another structure of the retaining ring of Figure 2;

图 8为本发明所提供电子膨胀阀第二种具体实施方式的结构示意图；图 9为图 8中阀针部件的结构示意图；图 10为图 8中阀针部件与挡圈和套筒装配后的结构示意图；图 11为图 8中挡圈的结构示意图； Figure 8 is a schematic structural view of a second embodiment of the electronic expansion valve provided by the present invention; Figure 9 is a schematic structural view of the valve needle member of Figure 8; Figure 10 is a structural schematic view of the valve needle member of Figure 8 after assembly with the retaining ring and the sleeve; Figure 11 is a schematic structural view of the retaining ring of Figure 8;

图 12为图 8中挡圈的另一种结构示意图； Figure 12 is a schematic view showing another structure of the retaining ring of Figure 8;

图 13为图 8中釆用封闭性挡圈的一种结构示意图； Figure 13 is a schematic view showing the structure of the closed retaining ring of Figure 8;

图 14为图 8中釆用封闭性挡圈的另一种结构示意图。 Fig. 14 is a schematic view showing another structure of the closed retaining ring of Fig. 8.

具体实施方式 detailed description

本发明的核心为提供一种电子膨胀阀，该电子膨胀阀的阀针部件的上移高度能够得到一定的限制，可以延长复位弹性部件的使用寿命。 The core of the present invention is to provide an electronic expansion valve whose lift height of the valve needle member can be limited to extend the service life of the return elastic member.

为了使本领域的技术人员更好地理解本发明的技术方案，下面结合附图和具体实施例对本发明作进一步的详细说明。其中，图 2-7为本发明第一种具体实施方式的结构示意图；图 8-14为本发明第二种具体实施方式的结构示意图。 In order to make those skilled in the art better understand the technical solutions of the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. 2-7 are schematic structural views of a first embodiment of the present invention; and FIGS. 8-14 are schematic structural views of a second embodiment of the present invention.

请参考图 2、图 3和图 4, 图 2为本发明所提供电子膨胀阀第一种具体实施方式的结构示意图；图 3为本发明所提供电子膨胀阀中阀针部件的结构示意图；图 4为图 3中阀针上端的横截面示意图；图 5为图 2中挡圈的结构示意图。 2, FIG. 3 and FIG. 4, FIG. 2 is a schematic structural view of a first embodiment of an electronic expansion valve according to the present invention; FIG. 3 is a schematic structural view of a valve needle member of the electronic expansion valve provided by the present invention; 4 is a schematic cross-sectional view of the upper end of the valve needle of FIG. 3; FIG. 5 is a schematic structural view of the retaining ring of FIG.

本发明所提供的电子膨胀阀，包括驱动机构（可以是图 2中所示的驱动电机 21 )、丝杆 25、螺母 24、阀座 27、以及阀针部件 26等，螺母 24 和阀座 27形成电子膨长阀的阀腔 30, 驱动电机 21可以釆用永磁式步进电机，驱动电机 21中转子转速还可以通过减速机 22减速，传动机构中螺纹副结构 23可以将转子的转动转化为螺纹副结构 23的轴向运动，则与螺纹副结构 23连接的丝杆 25可以在转动的同时，沿阀腔 30轴向上下移动，丝杆 25以及螺纹副结构 23位于螺母 24内，丝杆 25的下方同轴设置阀针部件 26, 阀针部件 26包括传力部件衬套 261 , 则丝杆 25向下移动时，可以带动阀针部件 26向下运动，随着阀针部件 26向下位移的逐渐增大，阀口 29的开度逐渐减小，直至完全封住阀口 29, 阀针部件 26还包括复位弹性部件，复位弹部件的上端可以通过焊接连接于阀体上，复位弹部件的下端可以通过焊接连接于阀杆 263上，复位弹性部件可以是波纹管 262或其他兼具有密封作用的筒形复位弹簧，由于波纹管管壁较薄，灵敏度较高，产品工艺成熟，所以优选釆用。如图 3所示，由于波纹管 262焊接固定在阀杆 263上，丝杆 25下移时，阀杆 263带动波纹管 262拉伸；丝杆 25向上移动时，在波纹管 262的复位作用下，阀针部件 26整体向上移动，阀口 29开度又逐渐增大。 The electronic expansion valve provided by the present invention includes a drive mechanism (which may be the drive motor 21 shown in FIG. 2), a lead screw 25, a nut 24, a valve seat 27, a valve needle member 26, etc., a nut 24 and a valve seat 27 The valve chamber 30 forming the electronic expansion valve, the driving motor 21 can be a permanent magnet type stepping motor, and the rotor speed in the driving motor 21 can also be decelerated by the speed reducer 22, and the thread substructure 23 in the transmission mechanism can convert the rotation of the rotor. For the axial movement of the thread sub-structure 23, the screw rod 25 connected to the thread sub-structure 23 can be moved up and down along the axial direction of the valve chamber 30 while rotating, and the screw rod 25 and the thread sub-structure 23 are located in the nut 24, A valve needle member 26 is disposed coaxially below the rod 25, and the valve needle member 26 includes a force transmitting member bushing 261. When the screw rod 25 moves downward, the needle member 26 can be moved downward, as the needle member 26 is moved toward The gradual increase of the lower displacement, the opening of the valve port 29 is gradually reduced until the valve port 29 is completely sealed, the valve needle member 26 further includes a return elastic member, and the upper end of the reset spring member can be connected to the valve body by welding, resetting Lower end of the elastic part By welding to the valve stem 263 to reset the elastic member 262 may be a bellows or other The cylindrical return spring which has a sealing effect is preferably used because the bellows tube wall is thin, the sensitivity is high, and the product process is mature. As shown in FIG. 3, since the bellows 262 is welded and fixed on the valve stem 263, when the screw rod 25 moves downward, the valve stem 263 drives the bellows 262 to stretch; when the screw rod 25 moves upward, under the action of the bellows 262 The valve needle member 26 is moved upward as a whole, and the opening degree of the valve port 29 is gradually increased.

本发明还包括设置于阀腔 30中的限位结构，且阀针部件 26具有横向凸缘，横向即与阀腔 30轴向垂直的方向，凸缘即相对于整体上大致呈杆状的阀针部件 26, 其上具有向外突出的部分，由于复位弹性部件的限制，凸缘位于复位弹性部件的下方。限位结构位于阀针部件 26上移至阀口 29处于最大开度时凸缘的上方，由于阀口 29的开度由阀针部件 26上下移动控制，因此，阀针部件 26上凸缘相对于限位结构的轴向位置是可变的，本发明所述的限位结构设于阀口 29处于最大开度时凸缘的上方，在正常工作状态下，阀针部件 26上移距离受驱动机构控制，上移至阀口 29恰好处于最大开度时，阀针部件继续上移的距离有限。限位结构具有轴向通道，轴向通道可供阀针部件 26凸缘部位以上的部分贯穿并上下移动，且轴向通道的径向最小尺寸小于凸缘的径向最大尺寸，则阀针部件 26继续上移时，限位结构至少会与凸缘的部分上端面抵触，则阀针部件 26无法继续上移。此处所述的上方并非限于阀针部件 26由轴向最低位置向上移动至阀口 29恰好处于最大开度时凸缘的上端面处，实际上限位结构也可以位于略高于此位置的一定距离处，即还可以允许阀针部件 26继续上移一定距离，此距离应保证尽量减少复位弹性部件的压缩量，本领域技术人员可以根据电子膨胀阀的具体型号和尺寸掌握。优选地，当阀针部件 26上移至阀口 29刚处于最大开度时，限位结构位与凸缘之间的轴向距离小于 lmm, 进一步地优化方案应将限位结构位与凸缘之间的轴向距离限制在 0.2mm-lmm之间。此夕卜，需要说明的是，文中所述的上方和下方，均以图 2所示的竖直放置的电子膨胀阀为基准，径向则以阀腔 30的横截面径向为描述视角。 The present invention also includes a stop structure disposed in the valve chamber 30, and the valve needle member 26 has a lateral flange that is transverse to the axial direction of the valve chamber 30, the flange being a generally rod-shaped valve relative to the entirety The needle member 26 has an outwardly projecting portion thereon, and the flange is located below the return elastic member due to the restriction of the return elastic member. The limit structure is located on the valve needle member 26 and moved above the flange when the valve port 29 is at the maximum opening degree. Since the opening degree of the valve port 29 is controlled by the valve needle member 26 moving up and down, the upper flange of the valve needle member 26 is relatively The axial position of the limiting structure is variable. The limiting structure of the present invention is disposed above the flange when the valve port 29 is at the maximum opening degree. Under normal working conditions, the valve needle member 26 is moved up by the distance. The drive mechanism controls the distance that the valve needle member continues to move up when the valve port 29 is just at the maximum opening. The limiting structure has an axial passage for the portion above the flange portion of the needle member 26 to penetrate and move up and down, and the radial minimum dimension of the axial passage is smaller than the radial maximum dimension of the flange, the valve needle member 26 When the upward movement is continued, the limit structure will at least interfere with the upper end surface of the flange, and the valve needle member 26 cannot continue to move up. The upper portion described herein is not limited to the fact that the valve needle member 26 is moved upward from the axially lowest position to the upper end surface of the flange when the valve port 29 is just at the maximum opening degree. In practice, the limit structure may also be located slightly above this position. At the distance, it is also possible to allow the needle member 26 to continue to move up a distance which is such as to ensure that the amount of compression of the resilient member is minimized, and those skilled in the art will be able to grasp the specific model and size of the electronic expansion valve. Preferably, when the valve needle member 26 is moved up to the valve opening 29 just at the maximum opening degree, the axial distance between the limiting structure position and the flange is less than 1 mm, and further optimization scheme should position the limiting structure with the flange The axial distance between them is limited to between 0.2 mm and 1 mm. Further, it should be noted that both the upper and lower sides described herein are based on the vertically placed electronic expansion valve shown in Fig. 2, and the radial direction is the radial direction of the cross section of the valve chamber 30.

该电子膨胀阀的阀腔 30中设有限位结构，则阀针部件 26上移至阀口 29最大时的位置处或略高于此位置时，会由于限位结构的抵触而无法继续上移，则阀针部件 26的上端部即使不与其他部件抵触，也无法上移，因此，当进行线圈拆换或其他需要使阀针部件 26与上方其他部件分离时，阀针部件 26不会在***压力下大幅上移，从而避免波纹管 262类复位弹性部件的过度压缩，延长复位弹性部件的使用寿命；且限位结构位于阀口 29处于最大开度时凸缘的上方，因此，限位结构在限制阀针部件 26上移时，不会影响阀针部件 26对阀口 29开度大小的控制。 The valve chamber 30 of the electronic expansion valve is provided with a limiting structure. When the valve needle member 26 is moved to the position of the valve port 29 at the maximum position or slightly higher than the position, the position of the valve member 26 cannot be moved upward due to the resistance of the limiting structure. Therefore, the upper end portion of the needle member 26 cannot move up even if it does not interfere with other members, and therefore, When the coil is removed or otherwise required to separate the needle member 26 from the other components above, the needle member 26 does not move up significantly under system pressure, thereby avoiding excessive compression of the bellows 262 type return elastic member and prolonging the return elasticity. The service life of the component; and the limit structure is located above the flange when the valve port 29 is at the maximum opening degree. Therefore, the limit structure does not affect the valve needle member 26 opening to the valve port 29 when the valve needle member 26 is moved up. Degree of control.

在第一种具体实施方式中 ,阀针部件 26下端阀针 264的最大外径可以大于阀杆 263的直径，如图 3所示阀针 264的上端面与阀杆 263形成台阶面，则此种结构的阀针 264可以作为凸缘结构；限位结构具体可以为环状的挡圈 28, 如图 5所示，即挡圈 28具有中心孔 281 , 并将挡圈 28的外周与阀腔 30的内壁定位，图 3中阀腔 30的内壁即阀座 27的内壁，当然，挡圈 28需位于阀口 29刚处于最大开度时阀针 264的上方，如图 2所示，阀座 27的内壁具有内凸缘，当阀针 264的上端面与内凸缘的上端面平齐时，阀口 29开度恰好最大，挡圈 28设于内凸缘处，阀针部件 26不再继续上移；挡圈 28的轴向高度也可以略高于此位置，则阀针部件 26还可以继续上移一定距离，之后，再与挡圈 28抵触，同样，此距离应保证尽量减少复位弹性部件的压缩量，釆取具体的挡圈 28作为限位结构，便于与阀腔 30内壁固定，且定位较为可靠。当然，限位结构并不限于挡圈 28的结构，也可以是对称设置于阀腔中的两个挡片，两个挡片之间形成轴向通道，理论上，一个挡片也可以实现本发明的目的，挡片的一端与阀腔内壁固定，另一端位于阀针 264的上方。本领域技术人员可以根据加工工艺、便于安装等因素选择合适形状的限位结构。 In the first embodiment, the maximum outer diameter of the valve needle 264 at the lower end of the needle member 26 may be larger than the diameter of the valve stem 263. As shown in FIG. 3, the upper end surface of the valve needle 264 forms a stepped surface with the valve stem 263. The valve needle 264 of the structure can be used as a flange structure; the limiting structure can be specifically an annular retaining ring 28, as shown in FIG. 5, that is, the retaining ring 28 has a central hole 281, and the outer circumference of the retaining ring 28 and the valve cavity The inner wall of the valve chamber 30 is positioned as the inner wall of the valve seat 27 in Fig. 3. Of course, the retaining ring 28 needs to be located above the valve needle 264 just before the valve opening 29 is at the maximum opening degree, as shown in Fig. 2, the valve seat The inner wall of 27 has an inner flange. When the upper end surface of the valve needle 264 is flush with the upper end surface of the inner flange, the valve opening 29 is opened to the maximum, the retaining ring 28 is provided at the inner flange, and the valve needle member 26 is no longer Continue to move up; the axial height of the retaining ring 28 can also be slightly higher than this position, then the valve needle member 26 can continue to move up a certain distance, and then with the retaining ring 28, again, this distance should ensure that the reset is minimized. The amount of compression of the elastic member, taking the specific retaining ring 28 as The limit structure is convenient for fixing with the inner wall of the valve cavity 30, and the positioning is relatively reliable. Of course, the limiting structure is not limited to the structure of the retaining ring 28, and may also be two blocking pieces symmetrically disposed in the valve cavity, and an axial passage is formed between the two blocking pieces. In theory, a blocking piece can also implement the present invention. For the purpose of the invention, one end of the flap is fixed to the inner wall of the valve chamber, and the other end is located above the valve needle 264. Those skilled in the art can select a suitable shape of the limiting structure according to the processing technology, the ease of installation and the like.

挡圈 28的中心孔 281即轴向通道，由于中心孔 281的径向最小尺寸小于凸缘的径向最大尺寸，在一定条件下，可以使阀针 264***挡圈 28的中心孔 281 , ***后，旋转一定角度，阀针 264与挡圈 28沿上方卡接。比如，阀针 264的外周大致呈十字形，中心孔 281也具有与阀针 264外周尺寸相当的十字形，则阀针 264可以***中心孔 281内，旋转一定角度，阀针 264 即无法向上移动。此种旋转卡接的限制上移方式，简便易行，在工艺上容易实现。可以釆取下述实施例的方式。 The central hole 281 of the retaining ring 28 is an axial passage. Since the radial minimum dimension of the central bore 281 is smaller than the radial maximum dimension of the flange, under certain conditions, the valve needle 264 can be inserted into the central hole 281 of the retaining ring 28, and inserted. Thereafter, after rotating at a certain angle, the valve needle 264 and the retaining ring 28 are snapped up. For example, the outer circumference of the valve needle 264 is substantially in the shape of a cross, and the center hole 281 also has a cross shape corresponding to the outer circumference of the valve needle 264. The valve needle 264 can be inserted into the center hole 281, and the valve needle 264 can not move upward by a certain angle. . The method of restricting the upward movement of the rotary card is simple and easy to implement, and is easy to implement in the process. The manner of the following embodiments can be taken.

阀针 264上端横截面的外周可以加工成大致呈方形的形状，如图 3和图 4所示，由于阀针 264需要沿阀腔 30轴向移动，阀针 264在方形的四个顶角处具有圓角，起到导向的作用，中心孔 281也为大致方形形状，如图 5所示，中心孔 281的方形边长 L大于阀针 264外周的方形边长 HI并小于阀针 264外周的最大对角线长度 H2, 最大对角线长度即径向最大尺寸。则在装配过程中，可以先将环状挡圈 28与阀座 27周壁定位，由于中心孔 281的方形边长 L大于阀针 264外周的方形边长 HI ,则选择适当的角度可以将阀针 264***挡圈 28的中心孔 281 内，当阀针 264位于中心孔 281 的下方之后，旋转阀针部件 26, 由于阀针 264外周的最大对角线长度 H2 大于中心孔 281的方形边长 L, 随着阀针部件 26的旋转，部分阀针 264的上端面必然会由挡圈 28遮挡，比如旋转 45。，使阀针 264外周最大对角线方向与中心孔 281方形边长方向垂直，此时阀针 264上端面能够与挡圈 28 抵触的面积最大，限位较为可靠。随着阀针部件 26上端其他部件的装配和定位，阀座 27上端面的口部与阀体可以进行铆接并焊接固定，则阀针部件 26与阀针 264的横向（与轴向垂直的方向）角度变动范围较小，在使用过程中，阀针部件 26上移至一定位置时，挡圈 28必然可以与阀针 264相互抵触，从而限制阀针部件 26上移。该种限位结构可以较为简便地实现限制阀针部件 26的上移。 The outer circumference of the cross section of the upper end of the valve needle 264 can be machined into a substantially square shape. As shown in Figures 3 and 4, since the valve needle 264 needs to move axially along the valve chamber 30, the valve needle 264 is at the four corners of the square. The circular hole has a function of guiding, and the center hole 281 is also substantially square. As shown in FIG. 5, the square side length L of the center hole 281 is larger than the square side length HI of the outer circumference of the valve needle 264 and smaller than the outer circumference of the valve needle 264. The maximum diagonal length H2, the maximum diagonal length is the radial maximum size. Then, during the assembly process, the annular retaining ring 28 and the peripheral wall of the valve seat 27 can be first positioned. Since the square side length L of the central hole 281 is larger than the square side length HI of the outer circumference of the valve needle 264, the valve needle can be selected at an appropriate angle. 264 is inserted into the center hole 281 of the retaining ring 28, and after the valve needle 264 is positioned below the center hole 281, the valve needle member 26 is rotated, since the maximum diagonal length H2 of the outer circumference of the valve needle 264 is larger than the square side length L of the center hole 281 With the rotation of the valve needle member 26, the upper end face of the partial valve needle 264 is necessarily blocked by the retaining ring 28, such as the rotation 45. The direction of the maximum diagonal of the outer circumference of the valve needle 264 is perpendicular to the longitudinal direction of the center hole 281. At this time, the upper end surface of the valve needle 264 can be the largest against the retaining ring 28, and the limit is relatively reliable. With the assembly and positioning of the other components at the upper end of the valve needle member 26, the mouth portion of the upper end surface of the valve seat 27 and the valve body can be riveted and welded, and the valve needle member 26 and the valve needle 264 are transverse (direction perpendicular to the axial direction). The angular variation range is small. When the valve needle member 26 is moved to a certain position during use, the retaining ring 28 can inevitably interfere with the valve needle 264, thereby restricting the valve needle member 26 from moving up. This type of limit structure makes it easier to limit the upward movement of the needle member 26.

如图 6和图 7所示，图 6为图 2中挡圈的另一种结构示意图；图 7为图 2中挡圈的又一种结构示意图。 As shown in FIG. 6 and FIG. 7, FIG. 6 is another structural diagram of the retaining ring of FIG. 2; FIG. 7 is another structural schematic view of the retaining ring of FIG.

在图 6 中，阀针 264上端横截面的外周形状为大致矩形，则挡圈 28 的中心孔 281也可以是大致矩形，中心孔 281的矩形长度 D大于阀针 264 外周的矩形长度，中心孔 281的矩形宽度 d大于阀针 264外周的矩形宽度，阀针 264外周的最大对角线长度大于中心孔 281的矩形宽度 d, 同样可以将阀针 264***中心孔 281 内，再旋转一定角度，比如 90°, 使阀针 264 外周长度方向与中心孔 281长度方向垂直，则阀针 264上移时，阀针 264 的上端面与挡圈 28 ·ί氐触。 In FIG. 6, the outer peripheral shape of the cross section of the upper end of the valve needle 264 is substantially rectangular, and the central hole 281 of the retaining ring 28 may also be substantially rectangular. The rectangular length D of the central hole 281 is larger than the rectangular length of the outer circumference of the valve needle 264, and the central hole The rectangular width d of the 281 is larger than the rectangular width of the outer circumference of the valve needle 264, and the maximum diagonal length of the outer circumference of the valve needle 264 is larger than the rectangular width d of the central hole 281. Similarly, the valve needle 264 can be inserted into the center hole 281 and rotated by a certain angle. For example, 90°, the longitudinal direction of the valve needle 264 is perpendicular to the longitudinal direction of the center hole 281, and when the valve needle 264 is moved up, the upper end surface of the valve needle 264 is in contact with the retaining ring 28 .

图 4和图 5所示的挡圈 28的外周形状均为圓形，实际上，挡圈 28外周的形状不受限制，便于与阀腔 30内壁定位即可。如图 6所示，挡圈 28 的外周形状也可以为大致矩形，挡圈 28的顶角处具有圓角，此种结构也可以适用于本发明，达到本发明的目的。 The outer peripheral shape of the retaining ring 28 shown in FIG. 4 and FIG. 5 is circular, in fact, outside the retaining ring 28 The shape of the circumference is not limited, and it is convenient to position the inner wall of the valve chamber 30. As shown in Fig. 6, the outer peripheral shape of the retaining ring 28 may also be substantially rectangular, and the apex angle of the retaining ring 28 may have rounded corners. Such a structure can also be applied to the present invention to attain the object of the present invention.

进一步地，为了将挡圈 28与阀腔 30内壁定位，可以在阀腔 30的内壁加工出与挡圈 28的外周适配的环形槽，当釆用外周为圓形的挡圈 28时，挡圈 28与环形凹槽的适配性较高，且圓形挡圈 28的加工较为简单。 Further, in order to position the retaining ring 28 and the inner wall of the valve chamber 30, an annular groove adapted to the outer circumference of the retaining ring 28 can be machined on the inner wall of the valve chamber 30, and when the outer peripheral ring is a circular retaining ring 28, the block is blocked. The fit of the ring 28 to the annular groove is relatively high, and the processing of the circular retaining ring 28 is relatively simple.

挡圈 28可以具有沿径向延伸的开口 282, 如图 4、图 5和图 6所示，环形的挡圈 28具有一个径向缺口，当挡圈 28的外周受到挤压时，由于挡圈 28具有径向缺口，挡圈 28的开口 282的两个端面具有合拢的趋势，则挡圈 28可以得到一定程度的收缩，如釆用金属材料的挡圈 28时，挡圈 28 具有较大的可收缩性，由于挡圈 28的外径需大于阀腔 30的内径，才可以将挡圈 28嵌入凹槽内以便定位，因此，将挡圈 28装入阀腔 30内时，挡圈 28会受到阀腔 30内周壁的挤压，而具有开口 282的挡圈 28可以较为方便地压装入阀腔 30内，至环形凹槽部位时，挡圈 28又可以自然扩张，嵌入环形凹槽内。因此，该环形挡圈 28的结构较为简单，且便于装配。 The retaining ring 28 can have a radially extending opening 282. As shown in Figures 4, 5 and 6, the annular retaining ring 28 has a radial indentation when the outer circumference of the retaining ring 28 is squeezed due to the retaining ring. 28 has a radial notch, and the two end faces of the opening 282 of the retaining ring 28 have a tendency to close, and the retaining ring 28 can be contracted to a certain extent. For example, when the retaining ring 28 of metal material is used, the retaining ring 28 has a larger Shrinkage, since the outer diameter of the retaining ring 28 needs to be larger than the inner diameter of the valve chamber 30, the retaining ring 28 can be inserted into the recess for positioning. Therefore, when the retaining ring 28 is inserted into the valve chamber 30, the retaining ring 28 will Pressed by the inner peripheral wall of the valve chamber 30, the retaining ring 28 having the opening 282 can be conveniently pressed into the valve chamber 30. When the annular groove is formed, the retaining ring 28 can be naturally expanded and embedded in the annular groove. . Therefore, the structure of the annular retaining ring 28 is relatively simple and easy to assemble.

请参考图 8、图 9和图 10, 图 8为本发明所提供电子膨胀阀第二种具体实施方式的结构示意图；图 9为图 8 中阀针部件的结构示意图；图 10 为图 8中阀针部件与挡圈和套筒装配后的结构示意图。 Please refer to FIG. 8 , FIG. 9 and FIG. 10 . FIG. 8 is a schematic structural view of a second embodiment of an electronic expansion valve according to the present invention; FIG. 9 is a schematic structural view of the valve needle component of FIG. 8; Schematic diagram of the valve pin assembly and the retaining ring and sleeve assembly.

该具体实施方式中的电子膨胀阀，包括驱动机构（可以是图 8中所示的驱动电机 21 )、丝杆 25、螺母 24、阀座 27、以及阀针部件 26等。阀体上具有阀腔 30, 驱动电机 21可以釆用永磁式步进电机，驱动电机 21中转子转速还可以通过减速机 22减速，传动机构中螺纹副结构 23可以将转子的转动转化为螺纹副结构 23的轴向运动，则与螺纹副结构 23配合的丝杆 25可以在转动的同时，沿阀腔 30轴向上下移动，丝杆 25以及螺纹副结构 23位于螺母 24内，丝杆 25的下方同轴设置阀针部件 26, 阀针部件 26包括传力部件衬套 261、阀杆 263以及位于阀杆 263末端的阀针 264 , 则丝杆 25向下移动时，可以带动阀杆 263和阀针 264向下运动，随着阀针 264向下位移的逐渐增大，阀口 29的开度逐渐减小，直至完全封住阀口 29, 阀针部件 26还包括复位弹性部件，复位弹部件的上端通过定位部件与阀体固定连接，定位部件可以是图 8中位于阀针部件顶部并具有中心孔的固定盖 265，复位弹性部件可以通过焊接固定于固定盖 265上，实现与阀体的固定，复位弹性部件可以是波纹管 262或其他兼具有密封作用的筒形复位弹簧，由于波纹管管壁较薄，灵敏度较高，产品工艺成熟，所以优选釆用。如图 9所示，由于波纹管 262的下端焊接固定在阀杆 263上，丝杆 25下移时，阀杆 263带动波纹管 262拉伸；丝杆 25向上移动时，在波纹管 262的复位作用和***的压力作用下，阀杆 263、阀针 264及衬套 261整体向上移动，阀口 29开度又逐渐增大。 The electronic expansion valve in this embodiment includes a drive mechanism (which may be the drive motor 21 shown in Fig. 8), a lead screw 25, a nut 24, a valve seat 27, a valve needle member 26, and the like. The valve body has a valve chamber 30, and the driving motor 21 can be driven by a permanent magnet type stepping motor. The rotor speed of the driving motor 21 can also be decelerated by the speed reducer 22. The thread substructure 23 of the transmission mechanism can convert the rotation of the rotor into a thread. The axial movement of the secondary structure 23 allows the screw 25 that cooperates with the threaded substructure 23 to move up and down along the axial direction of the valve chamber 30 while rotating. The lead screw 25 and the threaded substructure 23 are located within the nut 24, and the lead screw 25 The valve needle member 26 is coaxially disposed below, and the valve needle member 26 includes a force transmitting member bushing 261, a valve stem 263, and a valve needle 264 at the end of the valve stem 263. When the screw rod 25 moves downward, the valve stem 263 can be driven. And the valve needle 264 moves downward, and as the valve needle 264 is displaced downwardly, the opening of the valve port 29 is gradually reduced until the valve port 29 is completely sealed, and the valve needle member 26 further includes a return elastic member, which is reset. The upper end of the elastic member is fixed to the valve body by the positioning member The fixing member may be a fixing cover 265 located at the top of the valve needle member in FIG. 8 and having a center hole. The return elastic member may be fixed to the fixing cover 265 by welding to achieve fixing with the valve body, and the return elastic member may be corrugated. The tube 262 or other cylindrical return spring which has a sealing effect is preferably used because the bellows tube wall is thin, the sensitivity is high, and the product process is mature. As shown in FIG. 9, since the lower end of the bellows 262 is welded and fixed to the valve stem 263, when the screw rod 25 moves downward, the valve stem 263 drives the bellows 262 to stretch; when the screw rod 25 moves upward, the bellows 262 is reset. Under the action and the pressure of the system, the valve stem 263, the valve needle 264 and the bushing 261 move upward as a whole, and the opening degree of the valve port 29 gradually increases.

本发明还包括设置于阀腔 30中的限位部件，而且阀腔 30的内壁具有径向凸台 271 , 当然，该径向凸台 271必然不会限制阀针部件的轴向移动，如图 8所示，阀腔 30的上端直径较大，主要用于放置阀针部件包括波纹管 262的部分，阀腔 30的下端直径小于上端直径，主要对阀针 264起到导向的作用，因此，在阀座 27上形成向上的台阶面，以便形成大径阀腔段和小径阀腔段，可以在阀座 27的内壁加工出径向凸台 271。限位部件置于径向凸台 271上，同时在阀腔 30中还设置支撑件，支撑件位于定位部件和限位部件之间，定位部件即图 8中所示的固定盖 265 , 则装入阀腔 30后，限位部件与阀体之间实现轴向定位；此外，限位部件的底部具有轴向通道，阀杆 263上具有径向凸缘，凸缘位于轴向通道的下方，且轴向通道的径向最小尺寸小于径向凸缘的径向最大尺寸。 The present invention also includes a stop member disposed in the valve chamber 30, and the inner wall of the valve chamber 30 has a radial boss 271. Of course, the radial boss 271 necessarily does not limit the axial movement of the valve needle member, as shown in the figure. As shown in Fig. 8, the upper end of the valve chamber 30 has a large diameter, and is mainly used for placing a portion of the valve needle member including the bellows 262. The diameter of the lower end of the valve chamber 30 is smaller than the diameter of the upper end, and mainly serves as a guide for the valve needle 264. An upward stepped surface is formed on the valve seat 27 to form a large diameter valve chamber section and a small diameter valve chamber section, and a radial boss 271 can be formed on the inner wall of the valve seat 27. The limiting member is placed on the radial boss 271, and a support member is further disposed in the valve chamber 30. The support member is located between the positioning member and the limiting member, and the positioning member is the fixing cover 265 shown in FIG. After entering the valve chamber 30, axial positioning is achieved between the limiting member and the valve body; further, the bottom of the limiting member has an axial passage, the valve stem 263 has a radial flange, and the flange is located below the axial passage. And the radial minimum dimension of the axial passage is less than the radial maximum dimension of the radial flange.

则阀杆 263上移至一定程度时，凸缘会受限位部件的限制而无法继续上移，则衬套 261即使不与其他部件抵触，阀杆 263也无法上移。当然，限位部件的设置必然以满足电子膨胀阀的正常使用为前提，不影响阀口开度范围，即限位部件位于，阀杆 263上移至阀口开度最大时，凸缘的上方。因此，当进行线圈拆换或其他需要使阀针部件与上方其他部件分离时，阀杆不会在***压力下大幅上移，从而避免波纹管类复位弹性部件的过度压缩，延长复位弹性部件的使用寿命；此外，限位部件依靠位于径向凸台 271 和定位部件之间的支撑件进行定位，则限位部件和支撑件在装配时，置于径向凸台 271上即可，操作工序简单。 When the valve stem 263 is moved up to a certain extent, the flange is restricted by the positional component and cannot be moved up. Therefore, the bushing 261 cannot move up even if it does not interfere with other components. Of course, the setting of the limit member must meet the normal use of the electronic expansion valve, and does not affect the valve opening range, that is, the limit member is located, when the valve stem 263 is moved to the maximum opening of the valve port, above the flange . Therefore, when coil replacement or other need to separate the valve needle member from other components above, the valve stem does not move up significantly under system pressure, thereby avoiding excessive compression of the bellows type return elastic member and prolonging the reset elastic member. Service life; further, the limiting member is positioned by the support member located between the radial boss 271 and the positioning member, and the limiting member and the supporting member are placed on the radial boss 271 during assembly, and the operation process is performed. simple.

在该实施方式中支撑件为套筒 281 , 限位部件为具有中心孔 2821的挡圈 282, 装配后，挡圈 282置于径向凸台 271上，套筒 281的下端部置于挡圈 282上；阀针 264的最大外径大于阀杆 263的直径，如图 8所示，由阀针 264的上端面形成阀针部件的径向凸缘结构。 In this embodiment, the support member is a sleeve 281, and the limiting member is a block having a central hole 2821. After the assembly, the retaining ring 282 is placed on the radial boss 271, and the lower end of the sleeve 281 is placed on the retaining ring 282; the maximum outer diameter of the valve needle 264 is larger than the diameter of the valve stem 263, as shown in FIG. The radial flange structure of the valve needle member is formed by the upper end surface of the valve needle 264.

上述结构的具体装配过程如下：首先，将套筒 281外套阀针部件，即将阀针部件自阀针 264端***套筒 281内，阀针部件的固定盖 265的最大外径大于套筒 281的上端部直径，则套筒 281无法自阀针部件的顶部退出；其次，将挡圈 282外套于套筒 281和径向凸缘之间的阀杆 263上；最后，将装配限位部件和支撑件的阀针部件装入阀腔 30 内，阀针部件的固定盖 265与阀座 27的上端可以釆用铆接的方式固定，当然，也可以釆用其他常规的方式实现固定盖 265和阀体的固定，装入阀腔 30后的挡圈 282位于径向凸台 271上，套筒 281的下端部位于挡圈 282的表面之上，套筒 281的上端部位于固定盖 265之下。 The specific assembly process of the above structure is as follows: First, the sleeve 281 is fitted with the valve needle member, that is, the valve needle member is inserted into the sleeve 281 from the end of the valve needle 264, and the maximum outer diameter of the fixed cover 265 of the valve needle member is larger than that of the sleeve 281. The upper end diameter, the sleeve 281 can not be withdrawn from the top of the valve needle member; secondly, the retaining ring 282 is fitted over the valve stem 263 between the sleeve 281 and the radial flange; finally, the limit member and the support will be assembled The valve needle member of the valve member is inserted into the valve chamber 30, and the fixed cover 265 of the valve needle member and the upper end of the valve seat 27 can be fixed by riveting. Of course, the fixing cover 265 and the valve body can also be realized by other conventional methods. The retaining ring 282, which is inserted into the valve chamber 30, is located on the radial boss 271. The lower end of the sleeve 281 is located above the surface of the retaining ring 282, and the upper end of the sleeve 281 is located below the fixed cover 265.

图 8中，阀针部件下端阀针 264的最大外径大于阀杆 263的直径，与挡圈 282配合从而达到限制阀针部件上移的目的，即由阀针 264作为阀杆 263的径向凸缘，该结构阀针部件的结构较为简单。实际上，只要阀杆 263 具有与挡圈 282配合的径向凸缘即可实现本发明的目的，当然，该径向凸缘的最大外径至少大于挡圈 282的最小内径，方能实现限位的作用。 In Fig. 8, the maximum outer diameter of the valve needle member 264 at the lower end of the valve needle member is larger than the diameter of the valve stem 263, and cooperates with the retaining ring 282 to achieve the purpose of restricting the upward movement of the valve needle member, i.e., by the valve needle 264 as the radial direction of the valve stem 263. The flange, the structure of the valve needle member of the structure is relatively simple. In fact, the object of the present invention can be achieved as long as the valve stem 263 has a radial flange that cooperates with the retaining ring 282. Of course, the maximum outer diameter of the radial flange is at least greater than the minimum inner diameter of the retaining ring 282. The role of the bit.

请参考图 11 , 图 11为图 8中挡圈的结构示意图。 Please refer to FIG. 11, which is a schematic structural view of the retaining ring of FIG.

进一步地，挡圈 282可以具有连通其内周壁和外周壁的开口，且开口的轴向高度为所述挡圈的轴向高度，如图 11所示，环形的挡圈 282具有一个缺口，则在装配挡圈 282时，可以将挡圈 282的开口 2822直接卡向套筒 281和阀针 264上端面之间的阀杆 263部分，即将该阀杆 263部分卡入中心孔 2821 内，从而方便地装配挡圈 282, 挡圈 282的中心孔 2821可以是图 11中所示的圓形，其直径 D1小于阀针 264的最大外径 D2。实际上，根据上述挡圈 282的限位原理，中心孔 2821的具体形状并不受限制，如图 12所示，图 12为图 8中挡圈的另一种结构示意图，也可以加工出方形的中心孔 2821 , 其边长 D3小于阀针 264的最大外径 D2, 也可以实现本发明的目的。 Further, the retaining ring 282 may have an opening communicating with the inner peripheral wall and the outer peripheral wall thereof, and the axial height of the opening is the axial height of the retaining ring. As shown in FIG. 11, the annular retaining ring 282 has a notch. When the retaining ring 282 is assembled, the opening 2822 of the retaining ring 282 can be directly engaged with the valve stem 263 portion between the sleeve 281 and the upper end surface of the valve needle 264, that is, the valve stem 263 is partially inserted into the central hole 2821, thereby facilitating The collar 282 is fitted, and the central bore 2821 of the retaining ring 282 can be circular as shown in FIG. 11 with a diameter D1 that is less than the maximum outer diameter D2 of the valve needle 264. In fact, according to the limiting principle of the above-mentioned retaining ring 282, the specific shape of the central hole 2821 is not limited, as shown in FIG. 12, FIG. 12 is another structural schematic diagram of the retaining ring of FIG. 8, and a square shape can also be processed. The center hole 2821 whose side length D3 is smaller than the maximum outer diameter D2 of the valve needle 264 can also achieve the object of the present invention.

当然，挡圈 282也可以不设置开口 2822, 如图 13和图 14所示，图 13为图 8中釆用封闭性挡圈的一种结构示意图；图 14为图 8中釆用封闭性挡圈的另一种结构示意图。使用该两种结构的挡圈 282, 装配时，依次将套筒 281和挡圈 281 自阀杆 263的下端套入，最后，再装配阀针 263 , 同样可以实现本发明的目的，装配工序也较为简单。 Of course, the retaining ring 282 may not be provided with the opening 2822, as shown in FIG. 13 and FIG. 13 is a schematic structural view of the closed retaining ring of FIG. 8; FIG. 14 is another structural schematic view of the closed retaining ring of FIG. When the retaining ring 282 of the two structures is assembled, the sleeve 281 and the retaining ring 281 are sequentially inserted from the lower end of the valve stem 263, and finally, the valve needle 263 is assembled, and the object of the present invention can also be achieved. It's simpler.

由于阀口 29的开度由阀针部件上下移动控制，因此，阀杆 263末端阀针 264上端面相对于挡圈 282的轴向位置是可变的，上述实施例中的挡圈 282设于阀口 29处于最大开度时阀针 264上端面的上方，在正常工作状态下，阀杆 263上移距离受驱动机构控制，上移至阀口 29恰好处于最大开度时，阀杆 263继续上移的距离有限。挡圈 282的中心孔 2821为供凸缘以上阀杆 263贯穿并上下移动的轴向通道，当阀杆 263在刚好处于阀口 29最大开度后继续上移时，挡圈 282会与阀针 264上端面接触，使挡圈 282具有上移的趋势，进一步使套筒 281也具有上移趋势，而套筒 281的顶部与阀针部件顶部的固定盖 265抵触，因此，套筒 281和挡圈 282均无法沿轴向移动，因此，阀杆 263无法继续上移。此处所述的上方并非限于，阀杆 263 由轴向最低位置向上移动至阀口 29恰好处于最大开度时，阀针 264的上端面处，实际上挡圈 282也可以位于略高于此位置的一定距离处，即还可以允许阀杆 263继续上移一定距离，此距离应保证尽量减少复位弹性部件的选地，当阀杆 263上移至阀口 29刚处于最大开度时，挡圈 282与阀针 264 上端面之间的轴向距离小于 2mm, 进一步地，可以将挡圈 282与阀针 264 上端面之间的轴向距离限制在 0.2mm-lmm之间。此外，需要说明的是，文中所述的上方和下方，均以图 8所示的竖直放置的电子膨胀阀为基准，轴向即阀腔 30的轴线方向，径向则以阀腔 30的横截面径向为描述视角，与轴向垂直。 Since the opening degree of the valve port 29 is controlled by the valve needle member moving up and down, the axial position of the upper end surface of the valve needle 264 at the end of the valve stem 263 with respect to the retaining ring 282 is variable, and the retaining ring 282 of the above embodiment is provided at the valve. The port 29 is above the upper end surface of the valve needle 264 at the maximum opening degree. Under normal working conditions, the upward movement distance of the valve stem 263 is controlled by the driving mechanism, and when the valve opening 29 is moved to the maximum opening degree, the valve stem 263 continues. The distance moved is limited. The central hole 2821 of the retaining ring 282 is an axial passage through which the valve stem 263 is inserted and moved up and down. When the valve stem 263 continues to move up just after the maximum opening of the valve port 29, the retaining ring 282 and the valve needle The upper end surface contact of 264 causes the retaining ring 282 to have a tendency to move upward, further causing the sleeve 281 to also have an upward movement tendency, and the top of the sleeve 281 is in contact with the fixed cover 265 at the top of the valve needle member, and therefore, the sleeve 281 and the block None of the rings 282 can move in the axial direction, so the valve stem 263 cannot continue to move up. The upper portion described herein is not limited thereto, and when the valve stem 263 is moved upward from the axial lowest position to the valve opening 29 at the maximum opening degree, the upper end surface of the valve needle 264 may actually be located slightly above this. At a certain distance from the position, it is also possible to allow the valve stem 263 to continue to move up a certain distance, which should ensure that the selection of the resilient member is minimized, and when the valve stem 263 is moved up to the maximum opening of the valve port 29, The axial distance between the ring 282 and the upper end surface of the valve needle 264 is less than 2 mm. Further, the axial distance between the retaining ring 282 and the upper end surface of the valve needle 264 can be limited to between 0.2 mm and 1 mm. In addition, it should be noted that the upper and lower sides described herein are based on the vertically placed electronic expansion valve shown in FIG. 8 , the axial direction of the valve chamber 30, and the radial direction of the valve chamber 30. The cross-sectional radial direction is the described viewing angle, perpendicular to the axial direction.

在该实施方式中，限位部件为挡圈 282, 支撑件为套筒 281 , 二者的结构较为简单，便于实际加工，装配时，依次将套筒 281和挡圈 282外套阀针部件即可，拆除时，可以随阀针部件整体取出，拆装较为便利；而且，釆取套筒 281和挡圈 282结合的方式，承受阀杆 263上移的冲击力时，受力均匀，限位较为可靠。此外，基于本发明的限位原理，理论上，限位部件在轴向上与阀体定位即可，优选地方案可以使套筒 281为圓筒状，且套筒 281的外径大致等于径向凸台 271以上的阀腔 30的内径（即大径段阀腔的内径），如图 8所示，装配后，套筒 281可以抵靠于阀腔 30的内壁，则实际上套筒 281在轴向和径向上均得以定位，套筒 281牢靠定位的同时也实现了挡圈 282更为可靠地定位，从而进一步提高限位部件限制阀杆 263过度上移的可靠性。 In this embodiment, the limiting member is a retaining ring 282, and the supporting member is a sleeve 281. The structure of the two is relatively simple, which is convenient for actual processing. When assembling, the sleeve 281 and the retaining ring 282 are sequentially coated with the valve needle member. When dismantled, it can be taken out with the valve needle component as a whole, which is convenient to disassemble and assemble; Moreover, when the extraction sleeve 281 and the retaining ring 282 are combined, when the impact force of the valve stem 263 is moved upward, the force is even, and the limit is relatively reliable. In addition, based on the limiting principle of the present invention, in theory, the limiting member can be positioned in the axial direction with the valve body. Preferably, the sleeve 281 can be cylindrical, and the outer diameter of the sleeve 281 is approximately equal to the diameter. The inner diameter of the valve chamber 30 above the boss 271 (i.e., the inner diameter of the large-diameter valve chamber) is as shown in Fig. 8. After assembly, the sleeve 281 can abut against the inner wall of the valve chamber 30, and actually the sleeve 281 Positioned in both the axial and radial directions, the sleeve 281 is positioned securely while also achieving a more reliable positioning of the retaining ring 282, thereby further improving the reliability of the limit member limiting the excessive upward movement of the valve stem 263.

由支撑件和限位部件的工作原理可知，实际上，上述实施方式中的套筒 281并不限于完整的筒状结构，其长度大致等于挡圈 281至固定盖 265 之间的距离即可，略大于时，需满足固定盖 265与阀体固定装配，略小于时，需不影响挡圈 282的限位作用。此外，基于此原理，套筒 281的下端部也可以直接固定其他限位部件，比如套筒 281的下端部直接固定沿径向延伸的挡片，也可以实现本发明的目的，具体到上述实施方式中，挡圈 282 也可以与套筒 281的下端部固定连接，形成套筒 281的底部，当然，此种结构与阀针部件装配的简易度次于上述实施方式。 It can be seen from the working principle of the support member and the limiting member that, in fact, the sleeve 281 in the above embodiment is not limited to a complete cylindrical structure, and the length thereof is substantially equal to the distance between the retaining ring 281 and the fixed cover 265. When it is slightly larger than the fixed cover 265 and the valve body are fixedly assembled, when it is slightly smaller, the limit function of the retaining ring 282 is not affected. In addition, based on this principle, the lower end portion of the sleeve 281 can also directly fix other limiting members. For example, the lower end portion of the sleeve 281 directly fixes the radially extending blocking piece, and the object of the present invention can also be achieved, specifically to the above implementation. In the manner, the retaining ring 282 can also be fixedly coupled to the lower end of the sleeve 281 to form the bottom of the sleeve 281. Of course, the ease with which such a structure is assembled with the valve needle member is inferior to the above embodiment.

第一种具体实施方式和第二种具体实施方式中，均是在电子膨胀阀的阀腔内部设置具有限制阀针部件上移距离的部件，两种具体实施方式中分别设置了相对阀体固定且具有轴向通道的限位结构、限位部件，阀杆上设有横向凸缘（第二种具体实施方式表述为径向凸台）。二者的限位原理相同，但第二种具体实施方式在第一种具体实施方式的基础之上，进一步设置支撑件（如文中所述的套筒 281 ), 以实现限位部件的定位。因此，两种具体实施方式均通过限位部件和阀针部件的相互配合，达到限制阀针部件过度上移的目的。 In the first embodiment and the second embodiment, a component for restricting the upward movement distance of the valve needle member is disposed inside the valve cavity of the electronic expansion valve, and the two embodiments are respectively fixed with respect to the valve body. The limiting structure and the limiting member have an axial passage, and the valve stem is provided with a lateral flange (the second embodiment is expressed as a radial boss). The limiting principle of the two is the same, but the second embodiment is based on the first embodiment, and further supports a support member (such as the sleeve 281 described herein) to realize the positioning of the limiting member. Therefore, the two specific embodiments achieve the purpose of limiting the excessive movement of the valve needle member by the cooperation of the limiting member and the valve needle member.

以上对本发明所提供的一种电子膨胀阀进行了详细介绍。本文中应用了具体个例对本发明的原理及实施方式进行了阐述，以上实施例的说明只是用于帮助理解本发明的方法及其核心思想。应当指出，对于本技术领域的普通技术人员来说，在不脱离本发明原理的前提下，还可以对本发明进行若干改进和修饰，这些改进和修饰也落入本发明权利要求的保护范围内。 An electronic expansion valve provided by the present invention has been described in detail above. The principles and embodiments of the present invention have been described herein with reference to specific examples, and the description of the above embodiments is only to assist in understanding the method of the present invention and its core idea. It should be noted that those skilled in the art can make various modifications and changes to the present invention without departing from the spirit and scope of the invention.

Claims

权利要求 Rights request

1、一种电子膨胀阀，包括驱动机构、传动机构、阀座（27)和阀针部件（26); 所述阀针部件（26)具有沿电子膨胀阀的阀腔（30)轴向移动以控制阀口（ 29 )开度大小的阀针（ 264 )和阀杆（ 263 ) ,以及随所述阀针（ 264 ) 上下移动而缩回或拉伸的复位弹性部件，其特征在于，所述电子膨胀阀还包括设置于所述阀腔（30) 中且具有轴向通道的限位结构，所述阀针部件 (30)具有横向凸缘；所述限位结构位于所述阀针部件（26)上移至所述阀口（29)处于最大开度时所述凸缘的上方，且所述轴向通道的径向最小尺寸小于所述凸缘的径向最大尺寸。 An electronic expansion valve comprising a drive mechanism, a transmission mechanism, a valve seat (27) and a valve needle member (26); the valve needle member (26) having an axial movement along a valve chamber (30) of the electronic expansion valve a valve needle (264) and a valve stem (263) that control the opening of the valve port (29), and a return elastic member that is retracted or stretched as the valve needle (264) moves up and down, and is characterized in that The electronic expansion valve further includes a limiting structure disposed in the valve chamber (30) and having an axial passage, the valve needle member (30) having a lateral flange; the limiting structure being located at the valve needle member (26) moving up to the valve port (29) above the flange at maximum opening, and the radial minimum dimension of the axial passage is less than the radial maximum dimension of the flange.

2、根据权利要求 1所述的电子膨胀阀，其特征在于，所述阀针（264) 的最大外径大于所述阀杆（263 ) 的直径，所述凸缘为所述阀针（264)。 2. The electronic expansion valve according to claim 1, wherein a maximum outer diameter of the valve needle (264) is greater than a diameter of the valve stem (263), and the flange is the valve needle (264) ).

3、根据权利要求 2所述的电子膨胀阀，其特征在于，所述限位结构为具有中心孔（281 )的挡圈（28), 所述挡圈（28)的外周与所述阀腔（30) 的内壁定位，所述中心孔（281 )为所述轴向通道。 The electronic expansion valve according to claim 2, wherein the limiting structure is a retaining ring (28) having a central hole (281), an outer circumference of the retaining ring (28) and the valve cavity The inner wall of (30) is positioned, and the central hole (281) is the axial passage.

4、根据权利要求 3所述的电子膨胀阀，其特征在于，所述阀针（264) 横截面的外周大致为方形，所述中心孔（ 281 )大致为方形，所述中心孔（ 281 ) 的边长大于所述阀针（264)外周的边长并小于所述阀针（264)外周的最大对角线长度。 The electronic expansion valve according to claim 3, wherein the outer circumference of the cross section of the valve needle (264) is substantially square, the center hole (281) is substantially square, and the center hole (281) The side length is greater than the side length of the outer circumference of the valve needle (264) and smaller than the maximum diagonal length of the outer circumference of the valve needle (264).

5、根据权利要求 3所述的电子膨胀阀，其特征在于，所述阀针（264) 横截面的外周大致为矩形，所述中心孔（ 281 )大致为矩形，所述中心孔（ 281 ) 的长度大于所述阀针（264)外周的长度，所述中心孔（281 ) 的宽度大于所述阀针（264)外周的宽度，且所述中心孔（281 ) 的宽度小于所述阀针 (264)外周的最大对角线长度。 The electronic expansion valve according to claim 3, wherein the outer circumference of the cross section of the valve needle (264) is substantially rectangular, the center hole (281) is substantially rectangular, and the center hole (281) The length of the central hole (281) is greater than the width of the outer circumference of the valve needle (264), and the width of the central hole (281) is smaller than the valve needle. (264) The maximum diagonal length of the outer circumference.

6、根据权利要求 3至 5任一项所述的电子膨胀阀，其特征在于，所述阀座（27) 的内壁具有与所述挡圈（28) 的外周适配的环形凹槽，且所述挡圈（28)具有沿径向延伸的开口（282)。 The electronic expansion valve according to any one of claims 3 to 5, characterized in that the inner wall of the valve seat (27) has an annular groove adapted to the outer circumference of the retaining ring (28), and The retaining ring (28) has an opening (282) extending in a radial direction.

7、根据权利要求 3至 5任一项所述的电子膨胀阀，其特征在于，所述挡圈（28) 的外周大致为圓形。 The electronic expansion valve according to any one of claims 3 to 5, characterized in that the outer circumference of the retaining ring (28) is substantially circular.

8、根据权利要求 1至 5任一项所述的电子膨胀阀，其特征在于，当所述阀针部件（26)上移至所述阀口（29)处于最大开度时，所述限位结构与所述凸缘之间的轴向距离小于 lmm。 The electronic expansion valve according to any one of claims 1 to 5, characterized in that When the valve needle member (26) is moved up to the maximum opening of the valve port (29), the axial distance between the limiting structure and the flange is less than 1 mm.

9、根据权利要求 8所述的电子膨胀阀，其特征在于，当所述阀针部件 (26)上移至所述阀口（29)处于最大开度时，所述限位结构与所述凸缘之间的轴向巨离在 0.2mm- 1 mm之间。 The electronic expansion valve according to claim 8, wherein when the valve needle member (26) is moved up to the valve opening (29) at a maximum opening degree, the limiting structure and the The axial distance between the flanges is between 0.2 mm and 1 mm.

10、根据权利要求 1至 5任一项所述的电子膨胀阀，其特征在于，所述弹性部件为波纹管（262)。 The electronic expansion valve according to any one of claims 1 to 5, characterized in that the elastic member is a bellows (262).

11、一种电子膨月长阀，包括阀座（27)、沿阀腔（30)轴向移动的阀杆 ( 263 ), 以及随所述阀杆 ( 263 )移动而伸缩的复位弹性部件，所述复位弹性部件的上端通过定位部件定位于阀体上，其特征在于，所述阀腔（30) 中设有限位部件，所述阀腔（30) 的内壁具有径向凸台（271 ), 所述限位部件置于所述凸台（271 )上，且所述限位部件具有供所述阀杆（263 )贯穿的轴向通道；所述阀杆（263 )上具有位于所述轴向通道下方的径向凸缘，所述轴向通道的径向最小尺寸小于所述凸缘的径向最大尺寸；所述阀腔 (30) 中还设有支撑件，所述支撑件支撑于所述限位部件和所述定位部件之间。 11. An electronic inflation valve comprising a valve seat (27), a valve stem (263) that moves axially along the valve chamber (30), and a return resilient member that telescopes as the valve stem (263) moves. The upper end of the return elastic member is positioned on the valve body by the positioning member, wherein the valve chamber (30) is provided with a limiting member, and the inner wall of the valve chamber (30) has a radial boss (271) The limiting member is disposed on the boss (271), and the limiting member has an axial passage for the valve stem (263) to penetrate; the valve stem (263) has the a radial flange below the axial passage, the radial minimum dimension of the axial passage is smaller than a radial maximum dimension of the flange; the valve chamber (30) is further provided with a support member, the support member supports Between the limiting member and the positioning member.

12、根据权利要求 11所述的电子膨胀阀，其特征在于，所述限位部件为具有中心孔（2821 ) 的挡圈（282), 所述支撑件为外套所述复位弹性部件的套筒（281)。 The electronic expansion valve according to claim 11, wherein the limiting member is a retaining ring (282) having a central hole (2821), and the supporting member is a sleeve that covers the return elastic member. (281).

13、根据权利要求 12所述的电子膨胀阀，其特征在于，所述套筒（281 ) 为圓筒状，所述套筒（281 )置入所述阀腔（30)后，所述套筒（281 ) 的侧壁抵靠所述阀腔（30) 的内壁。 The electronic expansion valve according to claim 12, wherein the sleeve (281) is cylindrical, and after the sleeve (281) is placed in the valve chamber (30), the sleeve The side wall of the barrel (281) abuts against the inner wall of the valve chamber (30).

14、根据权利要求 11至 13任一项所述的电子膨胀阀，其特征在于，所述挡圈（282)具有连通其内周壁和外周壁的开口（2822), 且开口的轴向高度为所述挡圈（282) 的轴向高度。 The electronic expansion valve according to any one of claims 11 to 13, wherein the retaining ring (282) has an opening (2822) communicating with an inner peripheral wall and an outer peripheral wall thereof, and an axial height of the opening is The axial height of the retaining ring (282).

15、根据权利要求 14所述的电子膨胀阀，其特征在于，所述阀杆（263 ) 末端的阀针（264)为所述凸缘。 15. An electronic expansion valve according to claim 14 wherein the valve needle (264) at the end of the valve stem (263) is the flange.

16、根据权利要求 15 所述的电子膨胀阀，其特征在于，所述中心孔 (2821 ) 的形状为圓形，所述中心孔（2821 ) 的直径小于所述阀针（264) 的最大外径。 The electronic expansion valve according to claim 15, wherein the central hole (2821) has a circular shape, and the central hole (2821) has a smaller diameter than the valve needle (264). The maximum outer diameter.

17、根据权利要求 16 所述的电子膨胀阀，其特征在于，当所述阀杆 (263 )上移至所述阀口（29)处于最大开度时，所述挡圈（282) 与所述凸缘之间的轴向距离小于 2mm。 The electronic expansion valve according to claim 16, wherein when the valve stem (263) is moved up to the valve opening (29) at a maximum opening degree, the retaining ring (282) The axial distance between the flanges is less than 2 mm.

18、根据权利要求 17 所述的电子膨胀阀，其特征在于，当所述阀杆 (263 )上移至所述阀口（29)处于最大开度时，所述挡圈（282) 与所述凸缘之间的轴向距离在 0.2mm- 1 mm之间。 18. The electronic expansion valve according to claim 17, wherein the retaining ring (282) and the retaining ring (282) are moved when the valve stem (263) is moved up to the maximum opening of the valve port (29) The axial distance between the flanges is between 0.2 mm and 1 mm.

19、根据权利要求 18所述的电子膨胀阀，其特征在于，所述弹性部件为波纹管（262)。 The electronic expansion valve according to claim 18, wherein the elastic member is a bellows (262).