Electronic expansion valve

Abstract

Provided in the present application is an electronic expansion valve, comprising: a valve tube; a valve seat portion, which is connected to one end of the valve tube, wherein the valve seat portion is provided with a first cavity and a second cavity, the side wall of the first cavity being provided with a first flow port, and the second cavity being provided with a second flow port; a valve seat core, which is arranged in the valve seat portion and separates the first cavity from the second cavity, the valve seat core being provided with a valve port; a first filter structure, which is arranged in the first cavity, the first filter structure being used for filtering out impurities from the medium flowing in through the first flow port, and / or a second filter structure, which is arranged in the second cavity, the second filter structure being used for filtering out impurities from the medium flowing in through the second flow port; and a valve needle structure. By means of the present solution, regardless of whether the electronic expansion valve is used as a one-way flow valve or a two-way flow valve, the first filter structure and / or the second filter structure can effectively prevent impurities in the medium from entering the interior of the electronic expansion valve, thereby solving the problem of impurities in the medium of the electronic expansion valve blocking the interior of the electronic expansion valve.

Description

Electronic expansion valve TECHNICAL FIELD

[0001] The present application relates to the technical field of electronic expansion valves, in particular to an electronic expansion valve. BACKGROUND

[0002] Both flow ports of the electronic expansion valve can serve as a medium inlet, and the electronic expansion valve can realize bidirectional flow. In different air conditioning systems, the electronic expansion valve can be used as a unidirectional flow valve or a bidirectional flow valve. When the electronic expansion valve is used as a unidirectional flow valve, the medium enters the interior of the electronic expansion valve from one of the flow ports of the electronic expansion valve, and then flows out from the other flow port. When the electronic expansion valve is used as a bidirectional flow valve, the medium can enter the interior of the electronic expansion valve from the two flow ports in different flow directions. In the case of unidirectional flow or bidirectional flow, the medium can enter the interior of the electronic expansion valve through the communication hole, specifically, the medium enters the rotor cavity and the valve needle cavity in the interior of the electronic expansion valve, blocks the gap between the threaded segment of the valve needle structure and the nut structure or the guide segment of the valve needle structure and the nut structure, or blocks the gap between the rotor and the valve tube, causing the rotor or the valve needle structure to be stuck, which causes the performance of the electronic expansion valve to deteriorate or fail. Therefore, an electronic expansion valve that can prevent impurities from entering the valve needle cavity and the rotor cavity and avoid the rotor or the valve needle structure from being stuck is needed.

[0003] SUMMARY

[0004] The present application provides an electronic expansion valve to solve the problem of impurities in the medium of the electronic expansion valve blocking the interior of the electronic expansion valve in the prior art.

[0005] To solve the above problem, the present application provides an electronic expansion valve, comprising:

[0006] a valve tube;

[0007] a valve seat portion connected to one end of the valve tube, the valve seat portion having a first cavity and a second cavity, a side wall of the first cavity having a first flow port, and the second cavity having a second flow port;

[0008] a valve seat core fixed in the valve seat portion and separating the first cavity and the second cavity, the valve seat core having a valve port;

[0009] a first filter structure arranged in the first cavity, the first filter structure being used to filter impurities in the medium flowing into the first flow port; and / or,

[0010] a second filter structure arranged in the second cavity, the second filter structure being used to filter impurities in the medium flowing into the second flow port;

[0011] The valve needle structure is movably arranged in a cavity formed by the valve tube and the valve seat portion to open and close the valve port and adjust the opening degree.

[0012] Further, the electronic expansion valve further comprises a nut structure fixedly connected with the valve seat portion, the first filter structure extends along the axis of the electronic expansion valve, the first filter structure surrounds the valve needle structure, one end of the first filter structure is limitingly connected with the nut structure along the axis direction of the first filter structure, the other end of the first filter structure is limitingly connected with the valve seat core, the nut structure, the valve seat core and the first filter structure form a filter cavity, and the first filter structure prevents impurities in the medium flowing into the first flow-through port from entering the filter cavity.

[0013] Further, one end of the nut structure close to the valve seat core has a limiting section, one end of the first filter structure is sleeved on the limiting section, one end of the valve seat core close to the nut structure has a protruding section, and the other end of the first filter structure is sleeved on the protruding section.

[0014] Further, the first filter structure comprises a first filter screen, one end of the first filter screen is limitingly connected with the nut structure, and the other end of the first filter screen is limitingly connected with the valve seat core, or the first filter structure comprises a first filter screen and a first fixing sleeve, the first fixing sleeve is arranged at the end of the first filter screen to support the first filter screen, and the first fixing sleeve is connected with the nut structure and / or the valve seat core.

[0015] Further, the valve seat portion has a first limiting step, the second filter structure has a flange, the flange of the second filter structure is limitingly matched with the first limiting step, and the valve seat core is arranged on the side of the flange away from the first limiting step.

[0016] Further, the first limiting step has an inner ring and an outer ring, the diameter of the inner ring is smaller than the diameter of the outer ring to form the first limiting step, and an annular groove is arranged at the position close to the outer ring at the first limiting step, and the annular groove is used for placing a welding ring.

[0017] Further, the valve seat portion is an integral structure, and the inside of the valve seat portion has a cavity, and the cavity comprises a first cavity and a second cavity.

[0018] Further, the valve seat portion comprises a valve seat and a lower sleeve, and the valve seat has a first reduced diameter section away from the valve tube along the axis direction of the electronic expansion valve, and the outer periphery of the first reduced diameter section is matched and installed with the inner wall of the lower sleeve.

[0019] Further, the valve seat portion comprises a valve seat and a lower sleeve, the outer wall of the lower sleeve is matched and connected with the inner wall of the valve seat, the second filter structure has a flange, the flange of the second filter structure abuts against the side of the valve seat core away from the valve tube along the axis direction of the electronic expansion valve, and the end of the lower sleeve facing the valve seat core abuts against the side of the flange away from the valve tube.

[0020] Further, the valve seat part comprises a valve seat and a lower sleeve, the lower sleeve is connected to the valve seat away from the valve pipe, the second filter structure comprises a second fixed sleeve and a second filter screen, and the second fixed sleeve is fixed to the lower sleeve.

[0021] Further, the inner wall of the lower sleeve has an inwardly protruding limiting inward protrusion, and the limiting inward protrusion axially limits the second fixed sleeve away from the valve pipe.

[0022] Further, the limiting inward protrusion is a convex ring or a convex bubble.

[0023] Further, the outer periphery of the lower sleeve is connected to the inner wall of the valve seat, the valve seat has a second limiting step, the second limiting step axially and radially limits the valve seat core, and the valve seat core axially limits the second fixed sleeve close to the valve pipe.

[0024] Further, along the axis direction of the electronic expansion valve, the end of the valve seat away from the valve pipe has a first reduced diameter section, the outer periphery of the first reduced diameter section is connected to the inner wall of the lower sleeve, and the end face of the end of the valve seat away from the valve pipe abuts against the end of the second fixed sleeve away from the limiting inward protrusion.

[0025] Further, the outer periphery of the valve seat core is fixedly connected to the inner wall of the valve seat, the valve seat and the valve seat core are an integral structure, the valve seat core close to the lower sleeve is provided with a second reduced diameter section, and the second reduced diameter section axially limits the second fixed sleeve.

[0026] Further, the side wall of the lower sleeve has an annular folding edge, the folding edge axially limits the end of the second fixed sleeve away from the valve pipe, the end of the valve seat away from the valve pipe has a first reduced diameter section, the outer periphery of the first reduced diameter section is connected to the inner wall of the lower sleeve, and the end of the valve seat away from the valve pipe axially limits the end of the second fixed sleeve close to the valve pipe.

[0027] Further, the second filter structure comprises a second filter screen, the second filter screen is in a sheet shape, the valve seat part comprises a valve seat and a lower sleeve, the lower sleeve is connected to the valve seat away from the valve pipe, and the second filter screen is arranged between the lower sleeve and the valve seat.

[0028] Further, the end of the valve seat away from the valve pipe has a first reduced diameter section, the outer periphery of the first reduced diameter section is connected to the inner wall of the lower sleeve, the lower sleeve has a third limiting step, the third limiting step abuts against one side of the second filter screen, and the other side of the second filter screen abuts against the end face of the valve seat away from the valve pipe.

[0029] Further, the first filter structure comprises a first filter screen, the area of the actual filtering part of the first filter screen is S, the mesh number of the first filter screen is n, the wire diameter of the first filter screen is r, and the diameter of the valve port is d; or, the second filter structure comprises a second filter screen, the area of the actual filtering part of the second filter screen is S, the mesh number of the second filter screen is n, the wire diameter of the second filter screen is r, and the diameter of the valve port is d.

[0030] The first filter structure and / or the second filter structure need to meet:

[0031] Some embodiments of the present application provide an electronic expansion valve, comprising: a valve tube; a valve seat part connected with one end of the valve tube, the valve seat part having a first cavity and a second cavity, a side wall of the first cavity having a first flow passage, the second cavity having a second flow passage; a valve seat core arranged in the valve seat part and separating the first cavity and the second cavity, the valve seat core having a valve port; a first filter structure arranged in the first cavity, the first filter structure being used to filter impurities in medium flowing into the first flow passage; and / or, a second filter structure arranged in the second cavity, the second filter structure being used to filter impurities in medium flowing into the second flow passage; a valve needle structure movably arranged in a cavity formed by the valve tube and the valve seat part to open and close the valve port and adjust the opening degree.

[0032] By the present scheme, the valve seat core separates the valve seat part into the first cavity and the second cavity, the first filter structure is arranged in the first cavity to filter the medium entering from the first flow passage, avoiding impurities in the medium flowing from the first flow passage from entering the inside of the electronic expansion valve. The second filter structure is arranged in the second cavity to filter the medium entering from the second flow passage, avoiding impurities in the medium of the second flow passage from entering the inside of the electronic expansion valve. The valve needle structure reciprocally moves along the axial direction of the electronic expansion valve to realize the opening and closing of the valve port and the adjustment of the opening degree. When the electronic expansion valve is used as a one-way flow valve, the first filter structure or the second filter structure can individually filter impurities in the medium, avoiding impurities in the medium from entering the inside of the electronic expansion valve. When the electronic expansion valve is used as a two-way flow valve, the first filter structure can be arranged in the first cavity, and the second filter structure can be arranged in the second cavity, to avoid impurities in the fluid from entering the inside of the electronic expansion valve when the fluid flows in the forward and reverse directions in the electronic expansion valve.

[0033] By the arrangement of the first filter structure and / or the second filter structure, the present scheme effectively prevents impurities in the medium from entering the inside of the electronic expansion valve, specifically, prevents impurities in the medium from entering the rotor cavity and the valve needle cavity in the inside of the electronic expansion valve, blocking the gap between the threaded cooperation section of the valve needle structure and the nut structure or the guiding section of the valve needle structure and the nut structure, or blocking the gap between the rotor and the valve tube, avoiding the electronic expansion valve from being poor in performance or failing in performance caused by the rotor or the valve needle structure being stuck. BRIEF DESCRIPTION OF DRAWINGS

[0034] The accompanying drawings, which form a part of the present application, are intended to provide further understanding of the present application and are incorporated herein for a purpose of explanations of the present application and are not intended as improper limitations to the present application. In the drawings:

[0035] Fig. 1 shows a structural schematic diagram of an electronic expansion valve according to an embodiment of the present application;

[0036] Fig. 2 shows a partial enlarged view of A in Fig. 1;

[0037] Fig. 3 shows a structural schematic diagram of the nut structure of the electronic expansion valve in Fig. 1 from a top view;

[0038] Fig. 4 shows a structural schematic diagram of an electronic expansion valve according to another embodiment of the present application;

[0039] Fig. 5 shows a partial enlarged view of B in Fig. 4;

[0040] Fig. 6 shows a structural schematic diagram of an electronic expansion valve according to another embodiment of the present application;

[0041] Fig. 7 shows a partial enlarged view of C in Fig. 6;

[0042] Fig. 8 shows a structural schematic diagram of an electronic expansion valve according to another embodiment of the present application;

[0043] Fig. 9 shows a partial enlarged view of D in Fig. 8;

[0044] Fig. 10 shows a structural schematic diagram of an electronic expansion valve according to another embodiment of the present application;

[0045] Fig. 11 shows a partial enlarged view of E in Fig. 10;

[0046] Fig. 12 shows a structural schematic diagram of an electronic expansion valve according to another embodiment of the present application;

[0047] Fig. 13 shows a partial enlarged view of H in Fig. 12;

[0048] Fig. 14 shows a structural schematic diagram of an electronic expansion valve according to another embodiment of the present application;

[0049] Fig. 15 shows a partial enlarged view of F in Fig. 14;

[0050] Fig. 16 shows a structural schematic diagram of an electronic expansion valve according to another embodiment of the present application;

[0051] Fig. 17 shows a partial enlarged view of G in Fig. 16.

[0052] Wherein, the above-mentioned drawings include the following reference signs: 10, valve pipe; 20, valve seat part; 21, valve seat; 211, first reduced diameter section; 212, second limiting step; 22, lower sleeve; 221, limiting inner convex; 222, folded edge; 223, third limiting step; 23, first limiting step; 24, annular groove; 201, first cavity; 202, second cavity; 30, valve seat core; 31, convex section; 32, second reduced diameter section; 40, first filtering structure; 41, first filter screen; 42, first fixing sleeve; 50, second filtering structure; 51, second filter screen; 52, second fixing sleeve; 60, valve needle structure; 70, nut structure; 71, limiting section; 72, communication channel. DETAILED DESCRIPTION

[0053] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative, but not as any limitation on the present application and its application or use. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0054] As shown in FIGS. 1-2, the embodiment one of the present application provides an electronic expansion valve, comprising a valve pipe 10, a valve seat part 20, a valve seat core 30, a first filtering structure 40, a second filtering structure 50 and a valve needle structure 60, the valve seat part 20 is connected with one end of the valve pipe 10, the valve seat part 20 has a first cavity 201 and a second cavity 202, the side wall of the first cavity 201 has a first flow-through port, the second cavity 202 has a second flow-through port; the valve seat core 30 is arranged in the valve seat part 20 and separates the first cavity 201 and the second cavity 202, the valve seat core 30 has a valve port; the first filtering structure 40 is arranged in the first cavity 201, the first filtering structure 40 is used to filter impurities in the medium flowing into the first flow-through port; and / or, the second filtering structure 50 is arranged in the second cavity 202, the second filtering structure 50 is used to filter impurities in the medium flowing into the second flow-through port; the valve needle structure 60 is movably arranged in the cavity formed by the valve pipe 10 and the valve seat part 20 to open and close the valve port and adjust the opening degree.

[0055] The valve needle structure 60 can be a structure of valve needle and screw integrated, or a structure of valve needle and screw arranged in separate parts.

[0056] The valve seat core 30 separates the valve seat portion 20 into a first cavity 201 and a second cavity 202, so that the media in the first cavity 201 and the second cavity 202 are filtered respectively, increasing the effective area of the filter. The first filter structure 40 is arranged in the first cavity 201 to filter the media entering from the first flow port, preventing impurities in the media flowing from the first flow port from entering the interior of the electronic expansion valve. The second filter structure 50 is arranged in the second cavity 202 to filter the media entering from the second flow port, preventing impurities in the media of the second flow port from entering the interior of the electronic expansion valve. The valve needle structure 60 reciprocates along the axial direction of the electronic expansion valve to realize the opening and closing of the valve port and the adjustment of the opening degree.

[0057] When the electronic expansion valve is used as a one-way flow valve, the first filter structure or the second filter structure can individually filter impurities in the medium, preventing impurities in the medium from entering the interior of the electronic expansion valve. When the electronic expansion valve is used as a two-way flow valve, the first filter structure is arranged in the first cavity, and the second filter structure is arranged in the second cavity, to prevent impurities in the fluid from entering the interior of the electronic expansion valve when the fluid flows in both directions in the electronic expansion valve. The arrangement of the first filter structure and / or the second filter structure effectively prevents impurities in the medium from entering the interior of the electronic expansion valve, in particular, prevents impurities in the medium from entering the rotor cavity and the valve needle cavity in the interior of the electronic expansion valve, solving the problem of impurities in the medium of the electronic expansion valve blocking the gap between the rotor and the valve tube 10, the threaded fitting section between the valve needle structure 60 and the nut structure 70, or the gap between the valve needle structure 60 and the nut structure 70.

[0058] In some embodiments, the first flow port is arranged on the side wall of the first cavity 201, and the second flow port is arranged at the end of the second cavity 202 away from the valve seat core 30.

[0059] As shown in FIG. 2, the electronic expansion valve further includes a nut structure 70 fixedly connected with the valve seat portion 20, the first filter structure 40 extends along the axial direction of the electronic expansion valve, the first filter structure 40 surrounds the valve needle structure 60, along the axial direction of the first filter structure 40, one end of the first filter structure 40 is limitingly connected with the nut structure 70, and the other end of the first filter structure 40 is limitingly connected with the valve seat core 30, the nut structure 70, the valve seat core 30, and the first filter structure 40 form a filter cavity, and the first filter structure 40 prevents impurities in the medium flowing from the first flow port from entering the filter cavity.

[0060] In this way, the valve needle structure 60 moves relative to the nut structure 70 to open and close the valve port and adjust the opening degree. The nut structure 70, the valve seat core 30 and the first filter structure 40 form a filter cavity, and the first filter structure 40 prevents impurities in the medium flowing into the first flow port from entering the filter cavity, thereby avoiding impurities in the medium flowing from the first flow port from entering the internal part of the electronic expansion valve, blocking the gap between the rotor and the valve pipe 10, the threaded fitting section or the guide section between the valve needle structure and the nut structure 70.

[0061] In some embodiments, the first filter structure 40 includes a first filter screen 41, one end of the first filter screen 41 is limitingly connected with the nut structure 70, and the other end of the first filter screen 41 is limitingly connected with the valve seat core 30. The two ends of the first filter screen 41 are arranged on the nut structure 70 and the valve seat core 30 respectively, so that the nut structure 70 and the valve seat core 30 support and limit the two ends of the first filter screen 41 respectively, avoiding deformation or displacement of the first filter screen 41 under the impact of the medium.

[0062] In some embodiments, as shown in FIG. 3, the valve pipe 10 and the nut structure 70 have a rotor cavity, the nut structure 70 has a communication channel 72, and the communication channel 72 communicates the rotor cavity and the filter cavity. The first filter structure 40 prevents impurities in the medium flowing into the first flow port from entering the filter cavity, thereby avoiding impurities in the medium entering the rotor cavity through the communication channel 72, blocking the gap between the rotor and the valve pipe 10, the threaded fitting section or the guide section between the valve needle structure 60 and the nut structure 70.

[0063] Impurities in the medium flowing into the first flow port can enter the rotor cavity through the communication channel 72 of the nut structure 70 or the gap between the valve needle structure 60 and the nut structure 70, thereby blocking the gap between the rotor and the valve pipe 10, the threaded fitting section or the guide section between the valve needle structure and the nut structure 70, causing the valve needle structure or the rotor to be stuck. The first filter structure 40 forms a filter cavity, preventing impurities in the medium flowing into the first flow port from entering the communication channel 72 or the gap between the valve needle structure 60 and the nut structure 70. Impurities in the medium flowing into the second flow port can enter the second cavity 202, then enter the first cavity 201 through the valve port, and then enter the rotor cavity through the communication channel 72 of the nut structure 70 or the gap between the valve needle structure 60 and the nut structure 70. The second filter structure 50 intercepts impurities in the medium flowing into the second flow port in the second cavity 202, thereby preventing impurities from entering the valve needle cavity and the rotor cavity, and preventing impurities from blocking the gap between the rotor and the valve pipe 10, the threaded fitting section or the guide section between the valve needle structure 60 and the nut structure 70.

[0064] As shown in FIG. 1, the nut structure 70 has a limiting section 71 near one end of the valve seat core 30, and one end of the first filter structure 40 is sleeved on the limiting section 71. The valve seat core 30 has a protruding section 31 near one end of the nut structure 70, and the other end of the first filter structure 40 is sleeved on the protruding section 31. The protruding section 31 limits one end of the first filter structure 40 near the valve seat core 30, and the limiting section 71 limits the other end of the first filter structure 40 near the nut structure 70.

[0065] As shown in FIG. 2, the valve seat part 20 has a first limiting step 23, the second filter structure 50 has a flange, and the flange of the second filter structure 50 is limitedly matched with the first limiting step 23. The valve seat core 30 is arranged on the side of the flange away from the first limiting step 23.

[0066] With the above arrangement, the valve seat core 30 and the first limiting step 23 limit the two sides of the flange respectively, so that the flange is fixed on the valve seat part 20, and the second filter net 51 is fixed in the second cavity 202 through the flange of the second filter structure 50.

[0067] In some embodiments, the second filter structure 50 includes a second filter net 51 and a second fixing sleeve 52 for supporting the second filter net 51. The second fixing sleeve 52 includes a supporting section for supporting the second filter net 51 and a flange fixed on the valve seat part 20.

[0068] As shown in FIG. 2, the first limiting step 23 has an inner circle and an outer circle. The diameter of the inner circle is smaller than that of the outer circle, that is, the inner circle is closer to the axis of the electronic expansion valve than the outer circle. The first limiting step 23 is formed between the inner circle and the outer circle, that is, an end face for the flange to limit and abut is formed between the inner circle and the outer circle. An annular groove 24 is arranged at the position of the first limiting step 23 and near the outer circle. The annular groove 24 is used for placing a welding ring to furnace weld the valve seat core 30, the second filter structure 50 and the valve seat part 20. After the welding ring is placed in the annular groove 24, the valve seat core 30, the second filter structure 50 and the valve seat part 20 are furnace welded to fixedly connect the valve seat core 30, the second filter structure 50 and the valve seat part 20.

[0069] As shown in FIG. 2, the valve seat part 20 is an integral structure, and the inside of the valve seat part 20 has a cavity including a first cavity 201 and a second cavity 202. The valve seat core 30 divides the cylindrical cavity in the inside of the valve seat part 20 into the first cavity 201 and the second cavity 202. The first filter structure 40 in the first cavity 201 filters the medium entering through the first flow port, and the second filter structure 50 in the second cavity 202 filters the medium entering through the second flow port.

[0070] As shown in FIG. 4 and FIG. 5, in the second embodiment, different from the first embodiment, the valve seat part 20 comprises the valve seat 21 and the lower sleeve 22, the valve seat 21 has the first reduced diameter section 211 away from the one end of the valve pipe 10 along the axis direction of the electronic expansion valve, and the outer periphery of the first reduced diameter section 211 is installed in cooperation with the inner wall of the lower sleeve 22. The valve seat part 20 is provided as two separate bodies of the valve seat 21 and the lower sleeve 22, and the second flow passage is arranged in the lower sleeve 22, so as to reduce the processing difficulty through the split design.

[0071] In the first embodiment and the second embodiment, the welding ring is arranged in the annular groove 24, and the valve seat core 30 and the valve seat part 20 are welded through furnace welding, so as to limit the second filter structure 50.

[0072] As shown in FIG. 6 and FIG. 7, in the third embodiment, different from the first embodiment, the valve seat part 20 comprises the valve seat 21 and the lower sleeve 22, the outer wall of the lower sleeve 22 is connected in cooperation with the inner wall of the valve seat 21, the second filter structure 50 has the flange, the flange of the second filter structure 50 abuts against the side of the valve seat core 30 away from the valve pipe 10 along the axis direction of the electronic expansion valve, and the one end of the lower sleeve 22 towards the valve seat core 30 abuts against the side of the flange away from the valve pipe 10.

[0073] The outer wall of the lower sleeve 22 is connected in cooperation with the inner wall of the valve seat 21, so that the outer diameter of the lower sleeve 22 is smaller than the outer diameter of the valve seat 21, the outer diameter of the lower sleeve 22 is reduced through the split design of the valve seat 21 and the lower sleeve 22, the structure is miniaturized, the installation space of the electronic expansion valve is saved, and the processing difficulty is reduced through the split design.

[0074] As shown in FIG. 8 and FIG. 9, in the fourth embodiment, different from the first embodiment, the valve seat part 20 comprises the valve seat 21 and the lower sleeve 22, the one end of the lower sleeve 22 is connected away from the valve pipe 10, the second filter structure 50 comprises the second fixing sleeve 52 and the second filter screen 51, and the second fixing sleeve 52 is fixed to the lower sleeve 22. The second fixing sleeve 52 supports the second filter screen 51. The second fixing sleeve 52 is fixed to the lower sleeve 22 to fix the second filter screen 51, and the lower sleeve 22 limits the second fixing sleeve 52.

[0075] As shown in FIG. 9, the inner wall of the lower sleeve 22 has the limiting inner protrusion 221 protruding inwardly, and the limiting inner protrusion 221 axially limits the one end of the second fixing sleeve 52 away from the valve pipe 10. The limiting inner protrusion 221 is arranged on the inner wall of the lower sleeve 22, the one end of the second fixing sleeve 52 away from the valve pipe 10 is limited through the limiting inner protrusion 221, so that the second fixing sleeve 52 is limited in the lower sleeve 22.

[0076] In some embodiments, the limiting inner protrusion 221 is a protruding ring or a protruding bubble. When the limiting inner protrusion 221 is a protruding ring, the protruding ring is arranged circumferentially and axially limits the second fixing sleeve 52 so that the second fixing sleeve 52 cannot move axially relative to the protruding ring. When the limiting inner protrusion 221 is a protruding bubble, the protruding bubble protrudes from the inner wall of the lower sleeve 22 and the second fixing sleeve 52 is clamped on the inner wall of the lower sleeve 22 and cannot move axially.

[0077] As shown in FIG. 9, the outer periphery of the lower sleeve 22 is connected with the inner wall of the valve seat 21, and the valve seat 21 has a second limiting step 212 for axially and radially limiting the valve seat core 30, and the valve seat core 30 axially limits the second fixing sleeve 52 close to one end of the valve pipe 10. Specifically, the second limiting step includes a first limiting surface and a second limiting surface, the second limiting surface is located on the inner wall of the valve seat 21 and extends along the axis direction of the electronic expansion valve, and the second limiting surface and the outer peripheral surface of the valve seat core 30 abut to limit the radial displacement of the valve seat core 30; the first limiting surface is perpendicular to the axis direction of the electronic expansion valve, and the side of the valve seat core 30 away from the valve pipe 10 and the side of the second fixing sleeve 52 close to the valve pipe 10 abut along the axis direction of the electronic expansion valve, the first limiting surface faces the second flow passage, and the first limiting surface and the end of the valve seat core 30 away from the second flow passage abut to limit the displacement of the valve seat core 30 away from the second flow passage.

[0078] The limiting inner protrusion 221 axially limits the end of the second fixing sleeve 52 away from the valve pipe 10, and the second limiting step 212 axially limits the end of the second fixing sleeve 52 close to the valve pipe 10, so that the second fixing sleeve 52 cannot move axially, and the second filter screen 51 is fixed in the second cavity 202.

[0079] As shown in FIGS. 10 and 11, in Embodiment Five, the difference from Embodiment Four is that, along the axis direction of the electronic expansion valve, the end of the valve seat 21 away from the valve pipe 10 has a first reduced diameter section 211, the outer periphery of the first reduced diameter section 211 is connected with the inner wall of the lower sleeve 22, and the end face of the end of the valve seat 21 away from the valve pipe 10 abuts with the end of the second fixing sleeve 52 away from the limiting inner protrusion 221.

[0080] The outer periphery of the first reduced diameter section 211 of the valve seat 21 is connected with the inner wall of the lower sleeve 22, so that the valve seat 21 is connected with the lower sleeve 22. The limiting inner protrusion 221 axially limits the end of the second fixing sleeve 52 away from the valve pipe 10, and the end of the valve seat 21 away from the valve pipe 10 limits the other end of the second fixing sleeve 52, so that the second fixing sleeve 52 cannot move axially, and the second filter screen 51 is fixed in the second cavity 202 to filter the medium entering the second flow passage.

[0081] As shown in FIG. 12 and FIG. 13, in embodiment six, the first filter structure includes the first filter screen 41 and the first fixing sleeve 42, the first fixing sleeve 42 is arranged at the end of the first filter screen 41 to support the first filter screen 41, and the first fixing sleeve 42 is connected with the nut structure 70 and / or the valve seat core 30. The outer periphery of the valve seat core 30 is fixedly connected with the inner wall of the valve seat 21, the valve seat 21 and the valve seat core 30 are an integral structure, and the valve seat core 30 is provided with a second reduced diameter section 32 at the end close to the lower sleeve 22, and the second reduced diameter section 32 axially limits the second fixing sleeve 52.

[0082] The first fixing sleeve 42 is one or two, when one first fixing sleeve 42 is arranged, the first fixing sleeve 42 can be limited and matched with the nut structure 70 or the valve seat core 30 to support and limit the first filter screen 41; when two first fixing sleeves 42 are arranged, the two first fixing sleeves 42 are respectively limited and matched with the nut structure 70 or the valve seat core 30 to support and limit the first filter screen 41.

[0083] In some embodiments, the nut structure 70 or the valve seat core 30 has a groove to limit the first fixing sleeve 42.

[0084] The valve seat 21 and the valve seat core 30 are arranged as an integral structure, which reduces the installation difficulty of the electronic expansion valve, makes the installation of the electronic expansion valve more convenient and fast, saves the time cost, avoids welding connection of the valve seat 21 and the valve seat core 30, reduces the process, and avoids loosening or misplacement of the connection between the valve seat 21 and the valve seat core 30.

[0085] As shown in FIG. 14 and FIG. 15, in embodiment seven, the difference from embodiment four is that the side wall of the lower sleeve 22 has an annular folded edge 222, the folded edge 222 axially limits the end of the second fixing sleeve 52 away from the valve pipe 10, the end of the valve seat 21 away from the valve pipe 10 has a first reduced diameter section 211, the outer periphery of the first reduced diameter section 211 is matched and connected with the inner wall of the lower sleeve 22, and the end of the valve seat 21 away from the valve pipe 10 axially limits the end of the second fixing sleeve 52 close to the valve pipe 10.

[0086] The annular folded edge 222 limits the end of the second fixing sleeve 52 away from the valve pipe 10, the end of the valve seat 21 away from the valve pipe 10 limits the other end of the second fixing sleeve 52, so that the second fixing sleeve 52 cannot axially move, the second fixing sleeve 52 fixes the second filter screen 51 in the second cavity 202 to filter the medium entering through the second flow port.

[0087] As shown in FIG. 16 and FIG. 17, in embodiment eight, the difference from embodiment one is that the second filtering structure 50 comprises a second filter screen 51, the second filter screen 51 is in a sheet shape, the valve seat part 20 comprises a valve seat 21 and a lower sleeve 22, the lower sleeve 22 is connected with the valve seat 21 away from the valve pipe 10, and the second filter screen 51 is arranged between the lower sleeve 22 and the valve seat 21.

[0088] The second filter screen 51 is in a sheet shape, and the second filter screen 51 filters the medium entering the second flow passage to avoid impurities in the medium from entering the inside of the electronic expansion valve and causing blockage.

[0089] The valve seat core 30 and the valve seat part 20 are directly connected by laser welding, as in embodiments three to seven. Alternatively, an annular groove 24 is arranged on the valve seat part 20, a welding ring is placed in the annular groove 24, and the valve seat core 30 and the valve seat part 20 are connected by furnace welding, as in embodiments one and two.

[0090] Further, as shown in FIG. 17, the valve seat 21 away from the valve pipe 10 has a first reduced diameter section 211, the outer periphery of the first reduced diameter section 211 is connected with the inner wall of the lower sleeve 22, the lower sleeve 22 has a third limiting step 223, the third limiting step 223 abuts against one side of the second filter screen 51, and the other side of the second filter screen 51 abuts against the side end face of the valve seat 21 away from the valve pipe 10.

[0091] The first reduced diameter section 211 of the valve seat 21 is connected with the inner wall of the lower sleeve 22 to connect the valve seat 21 and the lower sleeve 22. The third limiting step 223 and the valve seat 21 limit the two sides of the second filter screen 51 respectively to fix the second filter screen 51 in the second cavity 202, so that the second filter screen 51 filters the medium entering the second flow passage.

[0092] Further, the first filtering structure 40 comprises a first filter screen 41, the actual filtering part of the first filter screen 41 has an area S, the first filter screen 41 has a mesh number n, the first filter screen 41 has a wire diameter r, and the valve port has a diameter d; or, the second filtering structure 50 comprises a second filter screen 51, the actual filtering part of the second filter screen 51 has an area S, the second filter screen 51 has a mesh number n, the second filter screen 51 has a wire diameter r, and the valve port has a diameter d.

[0093] The first filtering structure 40 and / or the second filtering structure 50 need to meet:

[0094] In order to filter smaller impurities, the first filter structure 40 and the second filter structure 50 with smaller pore size need to be arranged. The mesh of the first filter structure 40 and the second filter structure 50 with small pore size is easy to be blocked, so the effective filtering area of the first filter screen 41 and the second filter screen 51 needs to be increased, and the flow area corresponding to the part of the first filter structure 40 and / or the second filter structure 50 that actually plays a filtering role is greater than or equal to the diameter of the valve port, which can effectively reduce the throttling effect of the two filter structures on the refrigerant fluid passing through the valve port, and ensure the flow capacity of the electronic expansion valve.

[0095] Part of the area of the first filter screen 41 and the second filter screen 51 is used for positioning or contacting with other structures, such as the second fixed sleeve 52, the nut structure 70, and the valve seat core 30. Therefore, only part of the area of the first filter screen 41 and the second filter screen 51 actually plays a filtering role. The area actually playing a filtering role is the actual area of the first filter screen 41 and / or the second filter screen 51 minus the area used for positioning or contacting with other structures.

[0096] In some embodiments, the flow area of the pipeline connected with the first flow port and the second flow port is greater than the flow area of the valve port, and the cross-sectional area of the valve seat 21 is greater than the flow area of the pipeline connected with the first flow port and the second flow port.

[0097] The above only describes some embodiments of the present application and is not used to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An electronic expansion valve characterized by, The electronic expansion valve comprises: a valve pipe (10); a valve seat part (20) connected with one end of the valve pipe (10), the valve seat part (20) having a first cavity (201) and a second cavity (202), the side wall of the first cavity (201) having a first flow-through port, the second cavity (202) having a second flow-through port; a valve seat core (30) arranged in the valve seat part (20) and separating the first cavity (201) and the second cavity (202), the valve seat core (30) having a valve port; a first filter structure (40) arranged in the first cavity (201), the first filter structure (40) being used for filtering impurities in the medium flowing into the first flow-through port; or, a second filter structure (50) arranged in the second cavity (202), the second filter structure (50) being used for filtering impurities in the medium flowing into the second flow-through port; or, a first filter structure (40) and a second filter structure (50), the first filter structure (40) being arranged in the first cavity (201), the first filter structure (40) being used for filtering impurities in the medium flowing into the first flow-through port, the second filter structure (50) being arranged in the second cavity (202), the second filter structure (50) being used for filtering impurities in the medium flowing into the second flow-through port; a valve needle structure (60) movably arranged in the cavity formed by the valve pipe (10) and the valve seat part (20).

2. The electronic expansion valve according to claim 1, characterized in that The electronic expansion valve further comprises a nut structure (70) fixedly connected with the valve seat part (20), the first filter structure (40) extends along the axis of the electronic expansion valve, the first filter structure (40) surrounds the valve needle structure (60), one end of the first filter structure (40) is limitingly connected with the nut structure (70) along the axis direction of the first filter structure (40), the other end of the first filter structure (40) is limitingly connected with the valve seat core (30), the nut structure (70), the valve seat core (30) and the first filter structure (40) form a filter cavity, the first filter structure (40) prevents impurities in the medium flowing into the first flow-through port from entering the filter cavity.

3. The electronic expansion valve according to claim 2, characterized in that One end of the nut structure (70) close to the valve seat core (30) has a limiting section (71), one end of the first filter structure (40) is sleeved on the limiting section (71), one end of the valve seat core (30) close to the nut structure (70) has a protruding section (31), the other end of the first filter structure (40) is sleeved on the protruding section (31).

4. The electronic expansion valve according to claim 2, wherein The first filter structure (40) comprises a first filter screen (41), one end of the first filter screen (41) is limitingly connected with the nut structure (70), the other end of the first filter screen (41) is limitingly connected with the valve seat core (30). Or, the first filter structure comprises a first filter screen (41) and a first fixing sleeve (42), the first fixing sleeve (42) is arranged at the end of the first filter screen (41) to support the first filter screen (41), and the first fixing sleeve (42) is connected with the nut structure (70) and / or the valve seat core (30).

5. The electronic expansion valve according to claim 1, wherein The valve seat part (20) has a first limiting step (23), the second filter structure (50) has a flange, the flange of the second filter structure (50) is limitedly matched with the first limiting step (23), and the valve seat core (30) is arranged on the side of the flange away from the first limiting step (23).

6. The electronic expansion valve according to claim 5, wherein The first limiting step (23) has an inner ring and an outer ring, the diameter of the inner ring is smaller than that of the outer ring, so as to form the first limiting step (23), and an annular groove (24) is arranged at the position of the first limiting step (23) and close to the outer ring, and the annular groove (24) is used for placing a welding ring.

7. The electronic expansion valve according to claim 5, wherein The valve seat part (20) is an integral structure, the inside of the valve seat part (20) has a cavity, and the cavity comprises the first cavity (201) and the second cavity (202).

8. The electronic expansion valve according to claim 5, wherein The valve seat part (20) comprises a valve seat (21) and a lower sleeve (22), one end of the valve seat (21) away from the valve pipe (10) along the electronic expansion valve axis direction has a first reduced diameter section (211), and the outer periphery of the first reduced diameter section (211) is matched and installed with the inner wall of the lower sleeve (22).

9. The electronic expansion valve according to claim 1, wherein The valve seat part (20) comprises a valve seat (21) and a lower sleeve (22), the outer wall of the lower sleeve (22) is matched and connected with the inner wall of the valve seat (21), the second filter structure (50) has a flange, along the axis direction of the electronic expansion valve, the flange of the second filter structure (50) abuts against one side of the valve seat core (30) away from the valve pipe (10), and one end of the lower sleeve (22) toward the valve seat core (30) abuts against one side of the flange away from the valve pipe (10).

10. The electronic expansion valve according to claim 1, wherein The valve seat part (20) comprises a valve seat (21) and a lower sleeve (22), one end of the lower sleeve (22) away from the valve pipe (10) is connected with the valve seat (21), and the second filter structure (50) comprises a second fixing sleeve (52) and a second filter screen (51), the second fixing sleeve (52) is fixed to the lower sleeve (22).

11. The electronic expansion valve according to claim 10, wherein The inner wall of the lower sleeve (22) has a limiting inner protrusion (221) protruding inward, and the limiting inner protrusion (221) axially limits one end of the second fixing sleeve (52) away from the valve pipe (10).

12. The electronic expansion valve according to claim 11, wherein The outer periphery of the lower sleeve (22) is matched and connected with the inner wall of the valve seat (21), the valve seat (21) has a second limiting step (212), the second limiting step (212) axially and radially limits the valve seat core (30), and the valve seat core (30) is axially limited to one end of the second fixing sleeve (52) close to the valve pipe (10).

13. The electronic expansion valve of claim 11, wherein, The valve seat (21) has a first reduced diameter section (211) at one end away from the valve pipe (10) along the axis of the electronic expansion valve, and the outer periphery of the first reduced diameter section (211) is connected with the inner wall of the lower sleeve (22); and the end face of the one end of the valve seat (21) away from the valve pipe (10) abuts against the one end of the second fixed sleeve (52) away from the limiting inner convex (221).

14. The electronic expansion valve according to claim 13, wherein The valve seat (21) and the valve seat core (30) are in an integrated structure, and the valve seat core (30) is provided with a second reduced diameter section (32) at one end close to the lower sleeve (22), and the second reduced diameter section (32) axially limits the second fixed sleeve (52).

15. The electronic expansion valve of claim 10, wherein, The side wall of the lower sleeve (22) has an annular folded edge (222) for axially limiting the one end of the second fixed sleeve (52) away from the valve pipe (10), and the one end of the valve seat (21) away from the valve pipe (10) has a first reduced diameter section (211), and the outer periphery of the first reduced diameter section (211) is connected with the inner wall of the lower sleeve (22); and the one end of the valve seat (21) away from the valve pipe (10) axially limits the one end of the second fixed sleeve (52) close to the valve pipe (10).

16. The electronic expansion valve of claim 1, wherein The second filter structure (50) comprises a second filter screen (51), the valve seat part (20) comprises a valve seat (21) and a lower sleeve (22), the lower sleeve (22) is connected with the valve seat (21) at one end away from the valve pipe (10), and the second filter screen (51) is arranged between the lower sleeve (22) and the valve seat (21).

17. The electronic expansion valve according to claim 16, wherein The valve seat (21) has a first reduced diameter section (211) at one end away from the valve pipe (10) along the axis of the electronic expansion valve, and the outer periphery of the first reduced diameter section (211) is connected with the inner wall of the lower sleeve (22); and the end face of the one end of the valve seat (21) away from the valve pipe (10) abuts against the one end of the second fixed sleeve (52) away from the limiting inner convex (221).

18. The electronic expansion valve of claim 1, wherein, The first filter structure (40) comprises a first filter screen (41), the area of the part actually playing a filtering role of the first filter screen (41) is S, the mesh number of the first filter screen (41) is n, the wire diameter of the first filter screen (41) is r, and the diameter of the valve port is d; or, the second filter structure (50) comprises a second filter screen (51), the area of the part actually playing a filtering role of the second filter screen (51) is S, the mesh number of the second filter screen (51) is n, the wire diameter of the second filter screen (51) is r, and the diameter of the valve port is d. The first filter structure (40) and / or the second filter structure (50) need to satisfy:

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