Flow regulating mechanism in electronic expansion valve
By introducing ball screw drive into the electronic expansion valve, the problems of low transmission efficiency, poor accuracy, and poor stability are solved, achieving more efficient, quieter, and more stable flow regulation.
Patent Information
- Application Number
- CN202511188202.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-25
- Publication Date
- 2025-11-21
AI Technical Summary
Existing electronic expansion valves have low transmission efficiency, poor precision, high starting torque, are prone to noise and have poor stability, and are especially prone to stalling when there are minute impurities.
The ball screw drive is used instead of the sliding screw drive. By introducing a rolling ball thread connection between the screw and the upper sleeve, the smooth movement and precise control of the screw are ensured.
It improves transmission efficiency to 85%-90%, reduces starting torque by 50%, reduces noise, and effectively prevents stalling, achieving higher flow regulation accuracy and stability.
Smart Images
Figure CN120991501A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of mechanical technology, and more specifically to a flow regulating mechanism in an electronic expansion valve. Background Technology
[0002] Electronic expansion valves are "intelligent valves" in modern high-efficiency refrigeration systems. They achieve precise, rapid, and flexible adjustment of refrigerant flow through electronic control and are one of the core components for improving the energy efficiency, comfort, and intelligence of air conditioning and refrigeration equipment.
[0003] Electronic expansion valves play a role in the thermal management system of new energy vehicles by throttling and reducing pressure, controlling superheat, and regulating refrigerant flow. They can regulate the flow of refrigerant entering the refrigeration unit according to a preset program and are an important component of new energy vehicles.
[0004] Existing electronic valves generally consist of a stepper motor, rotor assembly, valve needle, and valve body. They all employ sliding screw drives, relying on sliding friction generated by mechanical contact to achieve axial movement. Direct screw drives suffer from low transmission efficiency and accuracy, high starting torque leading to operating noise. Furthermore, the presence of minute impurities in the screw can easily cause stalling, resulting in poor stability. Summary of the Invention
[0005] The purpose of this invention is to address the aforementioned problems in existing technologies by providing a flow regulation mechanism in an electronic expansion valve that operates smoothly and stably.
[0006] To achieve the above objectives, the present invention can be implemented through the following technical solutions:
[0007] A flow regulating mechanism in an electronic expansion valve, the electronic expansion valve including a valve body and a driving component, characterized in that the flow regulating mechanism in the electronic expansion valve includes a rotor, an upper sleeve, a valve seat and a valve needle, the valve body having an internal cavity, the valve seat being cylindrical and fixedly connected to the lower part of the valve body, the valve seat having an inlet communicating with its internal cavity on its side, and an outlet communicating with its internal cavity at its lower end, the upper sleeve being fixedly connected to the rotor, the lower end of the lead screw being connected to the upper end of the valve needle, the upper end of the lead screw being located inside the upper sleeve and the two being threadedly connected, the lower end of the valve needle being located inside the valve seat, the valve needle initially blocking the outlet, and the outlet being able to open when the valve needle moves upward, the valve body also having a connecting component that prevents the valve needle from rotating.
[0008] In the flow regulation mechanism of the aforementioned electronic expansion valve, a cylindrical connecting sleeve is fixedly connected to the valve body, the lower end of the lead screw has a cylindrical lower sleeve located inside the connecting sleeve, and the upper end of the valve needle is connected to the lower sleeve.
[0009] In the flow regulating mechanism of the electronic expansion valve, the connecting assembly comprises a limiting groove and a plug, the limiting groove is located on the side of the lower sleeve and is arranged axially, and the plug is fixed on the connecting cylinder and is inserted into the limiting groove.
[0010] In the flow regulating mechanism of the electronic expansion valve, the lower end of the lower sleeve is provided with a protruding stopper one, the valve needle is provided with a protruding stopper two, and the lower sleeve is further provided with a spring, the two ends of the spring are arranged on the lower sleeve and the valve needle respectively, and the stopper two has a tendency to abut against the stopper one under the elastic force of the spring.
[0011] In the flow regulating mechanism of the electronic expansion valve, the connecting cylinder and the upper sleeve are provided with a bearing.
[0012] In the flow regulating mechanism of the electronic expansion valve, the outer side of the screw rod is provided with a helical concave thread groove one, the inner side of the upper sleeve is provided with a helical concave thread groove two, the thread groove one and the thread groove two are opposite to each other and form a helical sliding channel therebetween, a plurality of balls are arranged along the length direction of the sliding channel and abut against the thread groove one and the thread groove two respectively.
[0013] In the flow regulating mechanism of the electronic expansion valve, the length of the thread groove one is greater than the length of the thread groove two.
[0014] In the flow regulating mechanism of the electronic expansion valve, a sleeve and a base are further included, the inside of the sleeve is a cavity and the lower end is open, the upper end of the base is fixed at the lower end of the sleeve, the rotor is located in the sleeve, and the upper end of the valve seat is connected with the base.
[0015] In the flow regulating mechanism of the electronic expansion valve, the upper end of the valve needle is provided with a protruding shoulder, the inner side of the base is provided with a protruding stopper, and the lower end of the connecting cylinder and the lower end of the lower sleeve abut against the valve seat and the shoulder is tightly pressed between the connecting seat and the stopper.
[0016] In the flow regulating mechanism of the electronic expansion valve, the valve needle is provided with a through hole penetrating through the two sides thereof, and the through hole is communicated with the inlet.
[0017] Compared with the prior art, the flow regulating mechanism of the electronic expansion valve has the following advantages because the screw rod and the upper sleeve are connected by the balls which can roll.
[0018] 1. The ball screw rod can display micron-level precision control, and the transmission precision is higher than that of the sliding screw rod, so that more subtle flow regulation can be realized.
[0019] 2. The ball screw has higher transmission efficiency, compared with the threaded sliding transmission, the transmission efficiency is increased from 30% to 85%~90%;
[0020] 3. The ball screw has lower friction coefficient, which can reduce the starting torque by 50% and is beneficial to reduce the starting noise of the electronic expansion valve;
[0021] Compared with the sliding screw, the gap between the threads during movement will produce a gap, the ball screw has smaller gap between the ball and the upper and lower screw during movement, and when there is fine impurities, the ball screw can isolate the impurities to effectively reduce the risk of electronic expansion valve stall.
[0022] Therefore, the flow regulating mechanism in the electronic expansion valve is smooth and has high stability when adjusting the flow. BRIEF DESCRIPTION OF DRAWINGS
[0023] Figure 1 is a perspective structural schematic diagram of the flow regulating mechanism in the electronic expansion valve.
[0024] Figure 2 is a front view structural schematic diagram of the flow regulating mechanism in the electronic expansion valve.
[0025] Figure 3 is Figure 2 a sectional view structural schematic diagram in the direction of A-A in
[0026] Figure 4 is a perspective structural schematic diagram of the flow regulating mechanism in the electronic expansion valve with the valve body hidden.
[0027] Figure 5 is Figure 4 a sectional view structural schematic diagram of
[0028] Figure 6 is a perspective structural schematic diagram of the connection between the screw rod and the upper sleeve.
[0029] Figure 7 is Figure 5 a local structural schematic diagram at B in
[0030] In the figure:
[0031] 1, valve body; 2, driving part; 3, rotor; 4, upper sleeve; 41, second threaded groove; 5, valve seat; 51, inlet; 52, outlet; 53, shoulder; 6, valve needle; 61, second stop edge; 63, through hole; 7, screw rod; 71, lower sleeve; 711, limiting groove; 712, first stop edge; 72, first threaded groove; 8, connecting cylinder; 9, latch; 10, spring; 11, bearing; 12, ball; 13, sleeve; 14, base; 141, convex edge. DETAILED DESCRIPTION
[0032] The following is a specific embodiment of the present application and further describes the technical solutions of the present application in conjunction with the accompanying drawings.
[0033] As shown in Figures 1-7 , the electronic expansion valve comprises a valve body 1 and a driving member 2.
[0034] The flow regulating mechanism in the electronic expansion valve comprises a rotor 3, an upper sleeve 4, a valve seat 5 and a valve needle 6, the valve body 1 is hollow, the valve seat 5 is cylindrical and is fixedly connected to the lower part of the valve body 1, the side part of the valve seat 5 has an inlet 51 communicating with the inner cavity thereof, the lower end of the valve seat 5 has an outlet 52 communicating with the inner cavity thereof, the upper sleeve 4 is fixedly connected to the rotor 3, the lower end of a lead screw 7 is connected to the upper end of the valve needle 6, the upper end of the lead screw 7 is located in the upper sleeve 4 and the two are threadedly connected, the lower end of the valve needle 6 is located in the valve seat 5, and the valve needle 6 blocks the outlet 52 in the initial state, the outlet 52 can be opened after the valve needle 6 moves upward, and the valve body 1 further has a connecting assembly capable of preventing the valve needle 6 from rotating.
[0035] The driving member 2 is an electromagnetic coil, and a magnetic field is formed at the rotor 3 after the driving member is energized, and the rotor 3 rotates under the action of the magnetic field.
[0036] Since the upper sleeve 4 is fixedly connected to the rotor 3, the upper sleeve 4 rotates together with the rotor 3. The rotation of the lead screw 7 is limited under the action of the connecting assembly, but the upper sleeve 4 is threadedly connected to the lead screw 7, so that the lead screw 7 moves up and down simultaneously during the rotation of the upper sleeve 4.
[0037] In the initial state, the valve needle 6 blocks the outlet of the valve seat 5, and at this time, the fluid medium entering the inlet 51 cannot be discharged from the outlet 52.
[0038] Conversely, after the lead screw 7 moves upward, the valve needle 6 is separated from the outlet 52, so that the fluid medium entering the inlet 51 is smoothly discharged from the outlet 52.
[0039] The upward movement amount of the valve needle 6 determines the output amount of the fluid medium at the outlet 52, that is, the valve needle 6 plays a role in controlling the flow adjustment of the entire electronic expansion valve.
[0040] The valve body 1 is fixedly connected with a cylindrical connecting cylinder 8, the lower end of the lead screw 7 has a cylindrical lower sleeve 71, and the lower sleeve 71 is located in the connecting cylinder 8, and the upper end of the valve needle 6 is connected to the lower sleeve 71.
[0041] The connecting assembly comprises a limiting groove 711 and a plug 9, the limiting groove 711 is located on the side part of the lower sleeve 71 and is arranged in the axial direction thereof, and the plug 9 is fixedly connected to the connecting cylinder 8 and is embedded in the limiting groove 711.
[0042] The connecting cylinder 8 has two functions:
[0043] One, provide enough position setting connecting assembly;
[0044] Two, the inner cavity of the connecting cylinder 8 matches with the lower sleeve 71, which ensures the stable up and down movement of the lower sleeve 71 and the lead screw 7.
[0045] The lower sleeve 71 has a protruding stopper 712 at the lower end, the valve needle 6 has a ring-shaped protruding stopper 61, and the lower sleeve 71 also has a spring 10, the two ends of the spring 10 act on the lower sleeve 71 and the valve needle 6 respectively, and the stopper 61 has a tendency to abut against the stopper 712 under the elastic force of the spring 10.
[0046] The stopper 61 abuts against the stopper 712 under the elastic force of the spring 10, which can make the valve needle 6 always have a downward tendency, and can buffer the valve needle 6 when it contacts the valve seat 5, avoiding rigid contact between the valve needle 6 and the valve seat 5.
[0047] The connecting cylinder 8 and the upper sleeve 4 have a bearing 11 therebetween.
[0048] The upper sleeve 4 can rotate smoothly under the action of the bearing 11.
[0049] The outer side of the lead screw 7 has a helical recessed thread groove one 72, and the inner side of the upper sleeve 4 has a helical recessed thread groove two 41, the thread groove one 72 and the thread groove two 41 are opposite and form a helical sliding channel therebetween, and a plurality of ball bearings 12 are arranged along the length direction of the sliding channel, and the two sides of the ball bearings 12 abut against the thread groove one 72 and the thread groove two 41 respectively.
[0050] The lead screw 7 and the upper sleeve 4 are threadedly connected, but they are not directly threadedly connected, and the thread connection is realized by the ball bearings 12.
[0051] That is, the lead screw 7 and the upper sleeve 4 are not threadedly connected without the ball bearings 12, and the lead screw 7 and the upper sleeve 4 are indirectly threadedly connected together after the two sides of the ball bearings 12 are embedded in the thread groove one 72 and the thread groove two 41 respectively.
[0052] The length dimension of the thread groove one 72 is greater than that of the thread groove two 41.
[0053] Such a structure can make the lead screw 7 move up and down smoothly and prevent the lead screw 7 from being stuck.
[0054] It also includes a sleeve 13 and a base 14, the inside of the sleeve 13 is a cavity and the lower end is open, the upper end of the base 14 is fixedly connected to the lower end of the sleeve 13, the rotor 3 is located in the sleeve 13, and the upper end of the valve seat 5 is connected with the base 14.
[0055] After the sleeve 13 and the base 14 are connected, the rotor 3, the upper sleeve 4, the screw rod 7 and other parts are located in the sleeve 13, and such a structure can protect the rotor 13 and other parts.
[0056] The upper end of the valve seat 5 has an annular convex shoulder 53, the inner side of the base 14 has an annular convex edge 14a, the lower end of the connecting cylinder 8 and the lower end of the lower sleeve 71 abut against the valve seat 5, and the convex shoulder 53 is tightly pressed between the connecting cylinder 8 and the convex edge 14a.
[0057] The convex shoulder 53 cooperates with the convex edge 141 to stably connect the upper end of the valve seat 5 to the base 14.
[0058] The valve needle 6 has a through hole 63 penetrating through both sides thereof, and the through hole 63 is communicated with the inlet 52.
[0059] The number of the inlets 52 is two, and the two inlets 52 are symmetrically arranged on both sides of the valve seat 5, and the through hole 63 on the valve needle 6 is located between the two inlets 52, and such a structure can keep the two inlets 52 in a conducting state at all times.
[0060] The flow regulating mechanism in the electronic expansion valve has the following advantages because the ball screw thread connection is used between the screw rod and the upper sleeve:
[0061] 1. The ball screw rod can display micron-level precision control, and compared with the sliding screw rod transmission, the ball screw rod transmission has higher precision and can realize more subtle flow regulation;
[0062] 2. The ball screw rod has higher transmission efficiency, and compared with the threaded sliding transmission, the transmission efficiency is increased from 30% to 85% to 90%;
[0063] 3. The ball screw rod has lower friction coefficient, can reduce the starting torque by 50%, and is beneficial to reducing the starting noise of the electronic expansion valve;
[0064] Compared with the sliding screw rod, the gap between the threads is generated in the movement process, the gap between the ball and the upper and lower screw rods is smaller when the ball screw rod moves, and when there is fine impurities, the ball screw rod can isolate the impurities from entering to effectively reduce the risk of electronic expansion valve stall.
[0065] Therefore, the flow regulating mechanism in the electronic expansion valve is smooth and has high stability when regulating the flow.
[0066] The technical scheme of the present application provides a solution significantly different from the prior art, and the parts not involved in the technical scheme of the present application are the same as or can be realized by the prior art, and will not be described here.
[0067] The technical solutions in the above embodiments have clearly and completely described the content of the present application. Apparently, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.
Claims
1. A flow regulating mechanism in an electronic expansion valve including a valve body and a drive member, characterized by, The flow regulating mechanism of the electronic expansion valve comprises a rotor, an upper sleeve, a valve seat and a valve needle, the valve body is a hollow cavity, the valve seat is a cylinder and is fixed to the lower part of the valve body, the side of the valve seat has an inlet communicating with the inner cavity, the lower end of the valve seat has an outlet communicating with the inner cavity, the upper sleeve is fixed in the rotor, the lower end of the screw rod is connected with the upper end of the valve needle, the upper end of the screw rod is located in the upper sleeve and is screwed with the upper sleeve, the lower end of the valve needle is located in the valve seat, the valve needle blocks the outlet in the initial state, and the outlet can be opened after the valve needle moves upward, and the valve body further has a connecting assembly capable of preventing the valve needle from rotating.
2. The flow regulating mechanism in an electronic expansion valve according to claim 1, wherein The valve body is fixed with a cylindrical connecting cylinder, the lower end of the screw rod has a cylindrical lower sleeve located in the connecting cylinder, and the upper end of the valve needle is connected with the lower sleeve.
3. The flow regulating mechanism in an electronic expansion valve according to claim 1, wherein The connecting assembly comprises a limiting groove and a plug, the limiting groove is located on the side of the lower sleeve and is arranged in the axial direction, and the plug is fixed to the connecting cylinder and is embedded in the limiting groove.
4. The flow regulating mechanism in an electronic expansion valve according to claim 1, wherein The lower end of the lower sleeve has a protruding stop flange one, the valve needle has a protruding annular stop flange two, the lower sleeve further has a spring, and the two ends of the spring act on the lower sleeve and the valve needle respectively, and the stop flange two has a tendency to abut against the stop flange one under the elastic force of the spring.
5. The flow regulating mechanism in an electronic expansion valve according to claim 1, wherein The connecting cylinder and the upper sleeve have a bearing therebetween.
6. The flow regulating mechanism in an electronic expansion valve according to claim 1 or 2 or 3 or 4 or 5, characterized in that, The outer side of the screw rod has a helical recessed thread groove one, the inner side of the upper sleeve has a helical recessed thread groove two, the thread groove one and the thread groove two are opposite to each other and form a helical sliding channel therebetween, and a plurality of balls are arranged along the length direction of the sliding channel and abut against the thread groove one and the thread groove two respectively.
7. The flow regulating mechanism in an electronic expansion valve according to claim 6, wherein The length of the thread groove one is greater than that of the thread groove two.
8. The flow regulating mechanism in an electronic expansion valve according to claim 7, wherein The valve further comprises a sleeve and a base, the inside of the sleeve is a hollow cavity and the lower end is open, the upper end of the base is fixed to the lower end of the sleeve, the rotor is located in the sleeve, and the upper end of the valve seat is connected with the base.
9. The flow regulating mechanism in an electronic expansion valve according to claim 8, wherein The upper end of the valve needle has a protruding annular shoulder, the inner side of the base has a protruding annular flange, and the lower end of the connecting cylinder and the lower end of the lower sleeve abut against the valve seat, and the shoulder is tightly pressed between the connecting seat and the flange.
10. The flow regulating mechanism in an electronic expansion valve according to claim 9, wherein The valve needle has a through hole penetrating through the two sides thereof, and the through hole communicates with the inlet.