Electric valve and control method thereof

Abstract

The electrically operated valve comprises a valve element seat and a valve element, the valve element seat is provided with a valve hole part, the valve element comprises an extending part, and the electrically operated valve is provided with a valve cavity; the electric valve at least comprises a first working state, in the first working state, at least part of the stretching-in part is located in a valve hole formed in the valve hole part, a flow channel is formed between the stretching-in part and the valve hole part and communicates with the valve cavity, and in the process that the valve element moves by a distance larger than zero, the flow of the flow channel is within the small flow range, so that the stability of the electric valve is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of fluid control, and particularly relates to an electric valve and a control method thereof. Background Art

[0002] An electric valve generally includes a controller, a motor, a transmission mechanism and a valve body. The controller sends a driving signal to the motor to control the rotation of the motor. The motor is in transmission connection with a valve core through the transmission mechanism, and the motor drives the valve core of the electric valve to move, so that the valve body reaches a corresponding opening degree to realize the regulation of the fluid flow rate.

[0003] For different electric valves, due to deviations in the manufacturing process or transmission structure, the stability of the electric valve, especially the stability of the flow rate, will be affected, thereby affecting the performance of the electric valve. Summary of the Invention

[0004] An object of the present application is to provide an electric valve and a control method thereof to improve the stability of the electric valve.

[0005] An embodiment of the present application provides an electric valve, including a valve core seat and a valve core. The valve core seat has a valve hole portion, the valve core includes an insertion portion, and the electric valve has a valve cavity. The electric valve has at least a first working state. In the first working state, at least a part of the insertion portion is located in the valve hole of the valve hole portion, and a flow channel is formed between the insertion portion and the valve hole portion. The flow channel communicates with the valve cavity. During the process that the valve core moves a distance greater than zero, the flow rate of the flow channel is within a small flow rate range.

[0006] In the electric valve provided by an embodiment of the present application, at least a part of the insertion portion is located in the valve hole of the valve hole portion, and a flow channel is formed between the insertion portion and the valve hole portion. During the process that the valve core moves a distance greater than zero, the flow rate of the flow channel is within a small flow rate range, thereby improving the stability of the electric valve.

[0007] Another embodiment of the present application provides an electric valve, including a valve core seat and a valve core. The valve core seat has a valve hole portion, the valve core includes an insertion portion, and the electric valve has a valve cavity. The electric valve has at least a first working state. In the first working state, at least a part of the insertion portion is located in the valve hole of the valve hole portion, and a flow channel is formed between the insertion portion and the valve hole portion. The flow channel communicates with the valve cavity. During the process that the valve core moves a distance greater than zero, the cross-sectional area of the flow channel is within a certain range.

[0008] In an electric valve provided by another embodiment of the present application, there is a flow channel between the extending portion and the valve hole portion. During the process of the valve core moving a distance greater than zero, the cross-sectional area of the flow channel is within a certain range, so that the flow rate of the flow channel is maintained within a certain range, thereby improving the stability of the electric valve.

[0009] An embodiment of the present application provides a control method for an electric valve. The electric valve includes a motor assembly and a valve core. The motor assembly includes a rotor assembly. The rotor assembly includes an output portion. The output portion is directly or indirectly drivingly connected to the valve core. Define the movement directions of the output portion to include a first direction and a second direction, and the first direction is opposite to the second direction. The control method of the electric valve includes: controlling the output portion to act in the first direction to make the rotor assembly reach the lower dead point; controlling the output portion to act in the second direction to a margin range.

[0010] In a control method for an electric valve provided by an embodiment of the present application, controlling the output portion to act in the second direction to a margin range enables the flow rate of the electric valve to more accurately reach a preset flow rate range, thereby improving the stability of the electric valve.

[0011] Another embodiment of the present application provides a control method for an electric valve. The control method of the electric valve includes: inserting at least a part of the extending portion into the valve hole of the valve hole portion, so that during the process of the extending portion moving a distance greater than zero, the flow rate of the flow channel is within a small flow rate range, where the flow channel is between the extending portion and the valve hole portion.

[0012] In a control method for an electric valve provided by another embodiment of the present application, inserting at least a part of the extending portion into the valve hole of the valve hole portion, so that during the process of the extending portion moving a distance greater than zero, the flow rate of the flow channel is within a small flow rate range, thereby improving the stability of the electric valve.

[0013] Another embodiment of the present application provides a control method for an electric valve. The control method of the electric valve includes: inserting at least a part of the extending portion into the valve hole of the valve hole portion, so that during the process of the extending portion moving a distance greater than zero, the cross-sectional area of the flow channel is within a certain range, where the flow channel is between the extending portion and the valve hole portion.

[0014] In a control method for an electric valve provided by another embodiment of the present application, inserting at least a part of the extending portion into the valve hole of the valve hole portion, so that during the process of the extending portion moving a distance greater than zero, the cross-sectional area of the flow channel is within a certain range, so that the flow rate of the flow channel is maintained within a certain range, thereby improving the stability of the electric valve. Description of the Drawings

[0015] Figure 1 Shows a schematic structural diagram of an embodiment of the electric valve of the present application;

[0016] Figure 2 Shows Figure 1 A schematic cross-sectional structural diagram of the shown electric valve along line A-A;

[0017] Figure 3 Shows Figure 2 A partially enlarged structural diagram of the shown electric valve at A;

[0018] Figure 4 Shows Figure 3 A partially enlarged structural diagram of the shown electric valve;

[0019] Figure 5 Shows Figure 3 A partially enlarged structural diagram of the shown electric valve when the valve core is in the first position;

[0020] Figure 6 Shows Figure 3 A partially enlarged structural diagram of the shown electric valve when the valve core is in the second position;

[0021] Figure 7 Shows Figure 2 The flow curve of the shown electric valve;

[0022] Figure 8 Shows Figure 7 A partially enlarged schematic diagram of the flow curve of the shown electric valve;

[0023] Figure 9 A partially enlarged schematic diagram of the flow curves of three electric valves with different valve opening positions;

[0024] Figure 10 Shows a partially enlarged schematic diagram of another embodiment of the electric valve of the present application;

[0025] Figure 11 Shows a partially enlarged schematic diagram of yet another embodiment of the electric valve of the present application.

[0026] Reference numerals:

[0027] 100. Electric valve; 1. Valve core seat; 11. Valve hole; 12. Second side wall; 13. Abutment surface; 14. Protruding rib; 15. Valve cavity; 16. First opening; 17. Second opening; 2. Valve core; 21. Sealing portion; 22. Insertion portion; 23. First side wall; 24. First inclined surface; 25. Second inclined surface; 26. Groove; 3. Motor assembly; 31. Stator assembly; 32. Rotor assembly; 33. Magnetic portion; 34. Output portion; 35. External thread portion; 4. Nut assembly; 41. Internal thread portion; 5. Valve body. Specific implementation method

[0028] The following is a detailed description of the embodiments in conjunction with the accompanying drawings.

[0029] In order to make the purpose, technical solutions and advantages of the present application more clear, the present application is further described in detail below in conjunction with the accompanying drawings and specific embodiments. In this article, relational terms such as "first" and "second" are only used to distinguish one component with the same name from another, and do not necessarily require or imply that there is any actual relationship or order between these components. It should be noted that the "limited connection" in this application includes snap-on connection, hinged connection, etc., and the "fixed connection" in this application includes threaded connection, welding, bonding, vulcanization fixation, riveting, insert injection molding, interference fit, etc.

[0030] If Figures 1-9 As shown in , the electric valve 100 includes a valve core seat 1, a valve core 2, a motor assembly 3, and a nut assembly 4. The motor assembly 3 includes a stator assembly 31 and a rotor assembly 32. The rotor assembly 32 can drive the valve core 2 to move. At least part of the stator assembly 31 is located on the periphery of the rotor assembly 32. The rotor assembly 32 includes an output portion 34 and a magnetic portion 33. The output portion 34 extends along the axial direction of the electric valve 100, and one end of the output portion 34 is directly or indirectly connected to the valve core 2. The nut assembly 4 is fixedly connected or limitedly connected to the valve core seat 1. The output portion 34 includes an external threaded portion 35. The nut assembly 4 includes an internal threaded portion 41, and the internal threaded portion 41 is meshed with the external threaded portion 35. The moving direction of the valve core 2 is defined as the axial direction of the electric valve 100. The axial direction of the electric valve 100 is Figure 3 is indicated by H. Through the meshing of the external threaded portion 35 and the internal threaded portion 41, the circumferential rotation of the rotor assembly 32 can be converted into axial movement, thereby driving the valve core 2 to move axially.

[0031] If Figures 2-5As shown, the valve core seat 1 has a valve hole portion 11, the valve core 2 includes an extending portion 22, the electric valve 100 has a valve cavity 15, and at least part of the valve core 2 is located in the valve cavity 15. The electric valve 100 has at least a first operating state. In the first operating state, the valve core 2 opens the valve hole portion 11, at least part of the extending portion is located in the valve hole of the valve hole portion 11, and there is a flow channel between the extending portion 22 and the valve hole portion 11. The flow channel communicates with the valve cavity 15, and the flow channel is at the narrowest part between the extending portion 22 and the valve hole portion 11. During the process of the valve core 2 moving a distance greater than zero, the cross-sectional area of the flow channel is within a certain range, so that the flow rate of the flow channel is kept within a certain range, thereby improving the stability of the electric valve 100, especially improving the stability of the flow rate of the electric valve 100, and thus improving the performance of the electric valve 100. It should be noted that "the output portion is indirectly drivingly connected to the valve core 2" means that the output portion is drivingly connected to the valve core 2 through transmission structures such as worm gears, gears, hinges, and limit connections.

[0032] For an air-conditioning system, under the mild conditions in some spring and autumn seasons, because the environmental conditions are unstable, the air conditioner may occasionally refrigerate and occasionally heat. Because the environmental load is very low, in this case, the flow rate that the throttle valve in the air-conditioning system needs to maintain is very small, such as 5 g / s. The throttle valve accurately reaching this small flow rate can improve the efficiency of the entire air-conditioning system. However, under the conditions in winter and summer seasons, due to the large load, the throttle valve needs to have a larger flow rate.

[0033] In this embodiment, in the first operating state, during the process of the valve core 2 moving a distance greater than zero, the flow rate of the flow channel is within the small flow rate range, so that the stability of the electric valve 100 can be improved, especially the stability of flow rate regulation, thereby improving the performance of the electric valve 100. When connecting the electric valve 100 as a throttle valve into the air-conditioning system, the flow rate of the electric valve 100 can more surely reach the required small flow rate range, thereby improving the efficiency of the air-conditioning system. At the same time, the electric valve 100 can also achieve the regulation of a larger flow rate range, can meet the needs of large loads, has a high integration degree and strong versatility. Specifically, the middle value of the small flow rate range is 1% - 5% of the full-open flow rate of the electric valve, preferably 1% - 3% of the full-open flow rate of the electric valve 100, such as 2%. Correspondingly, the cross-sectional area of the flow channel is 1% - 5% of the cross-sectional area of the valve hole portion 11, preferably 1% - 3% of the cross-sectional area of the valve hole portion 11, such as 2%. For example, if the cross-sectional area of the valve hole portion 11 is 7 mm 2 , then the cross-sectional area of this flow channel can be 0.1 mm 2 - 0.5 mm 2 , preferably 0.1 mm 2 - 0.3 mm 2 . The full-open flow rate is the flow rate corresponding to point f in Figure 7 .

[0034] As shown Figures 2-5 As shown, the insertion part 22 includes a first side wall part 23, the first side wall part 23 is located on the outer peripheral part of the insertion part 22, and the valve hole part 11 includes a second side wall part 12. In the first working state, the second side wall part 12 circumferentially surrounds the first side wall part 23 along the circumference of the electric valve 100, at least part of the first side wall part 23 faces the second side wall part 12, and a flow channel is formed between the first side wall part 23 and the second side wall part 12.

[0035] In this embodiment, the second side wall part 12 extends along the axial direction of the electric valve 100. During the process of the valve core 2 moving a certain distance, the cross-sectional area of the flow channel between the first side wall part 23 and the second side wall part 12 fluctuates within a smaller range, so that the flow rate of the flow channel is basically constant or fluctuates within a smaller range, thereby improving the stability of the electric valve 100. Specifically, the electric valve 100 can reach the small flow rate range more determinately, thereby improving the efficiency of the air conditioning system.

[0036] In this embodiment, the second side wall part 12 is in the shape of a cylindrical surface, which can improve the machining accuracy of the second side wall part 12, especially improve the accuracy of the radial dimension. The first side wall part 23 also extends along the axial direction of the electric valve 100, and the first side wall part 23 is in the shape of a cylindrical surface, which can improve the machining accuracy of the first side wall part 23, especially improve the accuracy of the radial dimension.

[0037] The motor assembly 3 is a stepping motor, and the stator assembly 31 can receive pulses to drive the rotor assembly 32 to rotate. Excluding the case of stalling, for each pulse received by the stator assembly 31, the rotor assembly 32 rotates one step, that is, the number of pulses corresponds to the rotation angle of the stator assembly 31, and the stroke of the output part 34 can be measured by the number of pulses received by the motor assembly 3. In other embodiments, the motor assembly 3 can also be a linear motor, a DC motor, etc., and the stroke of the output part 34 can be obtained through a Hall sensor or a potentiometer.

[0038] Figure 7 , Figure 8 shows a flow rate curve of an electric valve 100. Among them, the X-axis is the number of pulses (P), the Y-axis is the flow rate (Q). When the number of pulses is 0, the state of the electric valve 100 corresponds to Figure 8 point a in, at this time the rotor assembly 32 reaches the bottom dead center, and the valve core 2 blocks the valve hole part 11. As the number of pulses increases, the state of the electric valve 100 reaches Figure 8 point b in, at this time the valve core 2 just leaves the valve core seat 1, b is the valve opening point, or it can be said that point b is the end of the valve closing state. The first working state of the electric valve 100 includes a stable flow rate state. Figure 8 The section of the curve from point c to point d in corresponds to the stable flow rate state, and the aforementioned small flow rate range is the flow rate range corresponding to this stable flow rate state.

[0039] Figures 4-6 Shows the states of the electric valve 100 when the valve core 2 is in different positions. Figure 5 The position of the valve core 2 in corresponds to Figure 7 Point c in, that is, the state at the start of the stable flow state. Figure 6 The position of the valve core 2 in corresponds to Figure 7 Point d in, that is, the state at the end of the stable flow state. As Figure 4 shown, the electric valve 100 also includes a valve-closed state, in which the valve hole portion 11 is blocked by the valve core 2, and the flow rate of the electric valve 100 is basically 0. Figure 4 The position of the valve core 2 in corresponds to Figure 7 The flow curve from point a to point b in. The position of the valve core 2 is determined by Figure 4 changing to Figure 5 corresponds to the process from point b to point c in, during which the sealing portion 21 gradually moves away from the abutting surface 13, but the flow rate in this stage mainly depends on the flow area of the flow path between the extending portion 22 and the valve hole portion 11. Define Figure 7 The number of pulses experienced between the valve-opening point b and the starting point c of the stable flow state in as the intermediate pulse number. The intermediate pulse numbers of the electric valves 100 with different valve-opening points are basically the same. Figure 7 It should be noted that the upper, lower, left, right, front, rear and other orientation words mentioned in this specification are all based on the orientation of the drawings in the specification, only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, so it cannot be understood as a limitation to this application. "Extending along the axial direction of the electric valve" includes but is not limited to an angle of 0 with the axial direction of the electric valve, and also includes the case where the angle with the axial direction of the electric valve is less than 5°.

[0040] As

[0041] As Figures 2-5 shown, in this embodiment, the radial dimension of the second side wall portion 12 is smaller than the radial dimension of the rest of the valve hole portion 11, and the radial dimension of the first side wall portion 23 is larger than the radial dimension of the rest of the extending portion 22, that is, the second side wall portion 12 is the narrowest part of the valve hole portion 11, and the first side wall portion 23 is the widest part of the extending portion 22. Since the flow rate in the fluid passage is positively correlated with the diameter of the narrowest part of the electric valve 100, when the electric valve 100 is in the stable flow state, the flow path formed between the second side wall portion 12 and the first side wall portion 23 is the narrowest part of the entire fluid passage.

[0042] It should be noted that Figure 8The stable flow state in [description] is the ideal state, and the slope of the corresponding flow curve is 0. In actual situations, due to the influence of tolerances or the shape of the flow channel, the slope of the flow curve corresponding to the stable flow state may not be 0, and the flow rate corresponding to the stable flow state may fluctuate within a flow rate range, that is, within a small flow rate range. Therefore, by means such as improving the machining accuracy of the electric valve 100, making the difference between the upper limit and the lower limit of the small flow rate range less than 0.5% of the fully open flow rate of the electric valve, the difference between the upper limit and the lower limit of the small flow rate range can be made smaller, thereby improving the stability of the electric valve 100, especially the stability of small flow rate regulation.

[0043] Due to the existence of the radial dimensional tolerances of the first side wall portion 23 and the second side wall portion 12, for different electric valves 100, the cross-sectional area of the narrowest flow channel will be different, so the flow rates of the achieved stable flow states will also be different. In this application, by improving the machining accuracy, the radial dimensional tolerances of the first side wall portion 23 and the second side wall portion 12 are controlled within a range, such as within ±6μm, so that the flow rates of different electric valves 100 in the stable flow state are also controlled within a smaller interval, thereby improving the stability of the electric valve 100.

[0044] Due to some deviations in the manufacturing process, transmission structure, or operation process, each electric valve 100 manufactured from the same design drawing may have different valve opening positions, which can form a form similar to tolerances. For further illustration, Figure 9 shows the flow curves of three electric valves 100, Figure 9 The first valve in [description] is the flow curve of the designed electric valve 100, the second valve is the flow curve of the electric valve 100 with the maximum limit valve opening position, and the third valve is the flow curve of the electric valve 100 with the minimum limit valve opening position. Taking Figure 9 as an example, the valve opening position of the first valve is 38p, the valve opening position of the second valve is 53p, and the valve opening position of the third valve is 23p. Therefore, the tolerance of the valve opening position is ±15p.

[0045] Define the valve opening pulse deviation, which is the difference in the number of pulses between the maximum limit valve opening position and the minimum limit valve opening position. As Figure 9 shown, if the absolute value of the difference between the number of pulses at the start of the stable flow state and the number of pulses at the end of the stable flow state is greater than the valve opening pulse deviation, there can be a margin interval M. Within this margin interval M, even for electric valves 100 with different valve opening pulses, their flow rates are within the small flow rate range, so that electric valves 100 with different valve opening pulses can all reach the small flow rate range at a certain valve opening pulse, thereby improving the stability of the electric valve 100. Taking Figure 9For example, the number of pulses corresponding to the stable flow state is about 54p, and the valve opening pulse deviation is 30p. Therefore, the margin interval M is about the interval of 57p to 80p. That is to say, when the number of pulses of the electric valve 100 exceeds 57p but has not reached 80p, the electric valves 100 with different valve opening positions can all reach the preset small flow range.

[0046] Therefore, to improve the stability of the electric valve, the stable flow state needs to be long enough. The absolute value of the difference between the number of pulses at the start of the stable flow state and the number of pulses at the end of the stable flow state is greater than 4% of the full-open pulse number, so that the electric valves 100 with different valve opening pulses can all reach the small flow range at a certain valve opening pulse, thereby improving the stability of the electric valve 100. Define the full-open pulse number. The full-open pulse number is the number of pulses from the valve closing initialization position as zero to when the electric valve is fully open. For example Figure 7 the number of pulses corresponding to point f in []. Preferably, the absolute value of the difference between the number of pulses at the start of the stable flow state and the number of pulses at the end of the stable flow state is greater than 6% of the full-open pulse number, such as 7%, 8%, 9%, 10%, 12%. Specifically, the full-open pulse number can be 400p to 600p, the absolute value of the difference between the number of pulses at the start of the stable flow state and the number of pulses at the end of the stable flow state is 20p to 40p, and the range of the number of pulses corresponding to the start of the stable flow state can be 20p to 100p. The number of pulses corresponding to the end of the valve closing state is less than the number of pulses corresponding to the start of the stable flow state, and the range of the number of pulses corresponding to the end of the valve closing state can be 20p to 60p. It should be noted that the above "start" and "end" both refer to the endpoints of the pulse range, and the direction from valve closing to valve opening is used as the standard for start and end.

[0047] Correspondingly, taking this embodiment as an example, the second side wall portion 12 extends along the axial direction of the electric valve 100. The axial dimension of the second side wall portion 12 needs to be long enough to further improve the stability of the electric valve 100. The axial dimension of the second side wall portion 12 is greater than 4% of the total stroke of the valve core 2, so that the electric valves 100 with different valve opening pulses can all reach the small flow range at a certain valve opening pulse, thereby improving the

[0048] stability of the electric valve 100. Define the total stroke of the valve core 2 as the stroke that the valve core 2 travels from valve closing to full open.

[0049] Taking Figure 5 as an example, Figure 5 shows L1 in []. L1 is the axial distance from the upper end of the second side wall portion 12 to the lower end of the first side wall portion 23 when the electric valve 100 just enters the stable flow state. The dimension of L1 is greater than 4% of the total stroke of the valve core 2, and preferably greater than 6%.

[0050] The operating directions of the output unit 34 are defined to include a first direction and a second direction, and the first direction is opposite to the second direction. In this embodiment, both the first direction and the second direction are the rotational directions of the rotor assembly 32.

[0051] The control method of the electric valve 100 includes:

[0052] S1. Control the output unit 34 to act in the first direction so that the rotor assembly 32 reaches the bottom dead center; define the bottom dead center of the rotor assembly as the zero point of the pulse number. This step can enable the rotor assembly 32 to reach Figure 7 the position where the pulse number is 0, thereby realizing the initialization of the electric valve 100.

[0053] S2. Control the output unit 34 to act in the second direction to the margin interval.

[0054] Enable electric valves 100 with different opening valve pulses to reach the small flow range at a certain opening valve pulse, thereby improving the stability of the electric valve and the operating efficiency of the system.

[0055] Specifically, step S2 includes: controlling the output unit 34 to act in the second direction for a first stroke, and the first stroke is greater than or equal to the stroke of the output unit 34 corresponding to the sum of the maximum limit opening valve pulse number and the intermediate pulse number. The "maximum limit opening valve pulse number" is the pulse number corresponding to the aforementioned maximum limit opening valve position.

[0056] The valve seat 1 includes an abutting surface 13, the abutting surface 13 surrounds the valve hole portion 11, the valve core 2 includes a sealing portion 21, and the sealing portion 21 can abut against the abutting surface 13 to block the valve hole portion 11, and the flow rate is zero when the valve hole portion 11 is blocked; along the axial direction of the electric valve 100, the sealing portion 21 is farther from the valve hole portion 11 than the extending portion 22.

[0057] As Figures 2-5 shown, the extending portion 22 includes a first inclined surface 24. Along the axial direction of the electric valve 100, the first inclined surface 24 is farther from the sealing portion 21 than the first side wall portion 23. The first inclined surface 24 is adjacent to the first side wall portion 23, and the radial dimension of the first inclined surface 24 decreases in the direction away from the sealing portion 21. The first inclined surface 24 cooperates with the wall forming the valve hole portion 11. By moving the valve core 2, the flow rate of the electric valve 100 can be adjusted within a pulse number range, such as Figure 7 、 Figure 8 the line segment from the midpoint d to the point e. Specifically, the first inclined surface 24 is a conical surface, and the angle between the first inclined surface 24 and the axial direction of the electric valve 100 is less than 10°. This can make the flow rate curve within this pulse number range smoother, that is, the flow rate change generated by the valve core 2 moving a unit distance is smaller, thereby improving the accuracy of flow rate adjustment at the initial stage of valve opening. Specifically, the angle between the first inclined surface 24 and the axial direction of the electric valve 100 is greater than the angle between the first side wall portion 22 and the axial direction of the electric valve 100.

[0058] The insertion part 22 includes a second inclined surface 25. Along the axial direction of the electric valve 100, the second inclined surface 25 is farther from the sealing part 21 than the first inclined surface 24. The second inclined surface 25 is adjacent to the first inclined surface 24, and the radial dimension of the second inclined surface 25 decreases in the direction away from the sealing part 21. Specifically, the second inclined surface 25 is a conical surface, and the angle between the second inclined surface 25 and the axial direction of the electric valve 100 is greater than the angle between the first inclined surface 24 and the axial direction of the electric valve 100. The second inclined surface 25 cooperates with the wall forming the valve hole part 11. By moving the valve core 2, the flow rate of the electric valve 100 can be adjusted within a pulse number range. For example Figure 7 the line segment from point e to point f in. The flow rate curve within this pulse number range is located in the stage close to fully open during the valve opening process. The angle between the second inclined surface 25 and the axial direction of the electric valve 100 is greater than the angle between the first inclined surface 24 and the axial direction of the electric valve 100, so that the flow rate change generated by the valve core 2 moving a unit distance is larger, and the fully open state can be completed within a shorter stroke of the valve core 2, reducing the axial length of the valve core 2. In this embodiment, the preferred range of the angle between the second inclined surface 25 and the axial direction of the electric valve 100 is between 30° and 50°.

[0059] As Figures 2-5 shown, the sealing part 21 extends radially outward from the insertion part 22 along the electric valve 100. The insertion part 22 includes a groove 26. Along the axial direction of the electric valve 100, the groove 26 is located between the first side wall part 23 and the sealing part 21. Along the radial direction of the electric valve 100, the groove 26 is recessed inward compared with the first side wall part 23, and the wall forming the groove 26 is adjacent to the sealing part 21. The groove 26 plays a role of "fillet clearing", so that the part between the first side wall part 23 and the sealing part 21 will not contact the abutting surface 13 and affect the sealing.

[0060] The valve core seat 1 includes a rib 14 protruding towards the sealing part 21. The rib 14 surrounds the valve hole part 11, and the abutting surface 13 is located at one end of the rib 14 relatively close to the sealing part 21. In this embodiment, the abutting surface 13 is planar and extends along the radial direction of the electric valve 100. In other embodiments, the abutting surface 13 can also arch towards the sealing part 21. Setting the abutting surface 13 at the top of the rib 14 facilitates the cutting process of the abutting surface 13.

[0061] The valve core seat 1 has a valve cavity 15. The valve core seat 1 has a first opening 16 and a second opening 17. The first opening 16 communicates with the valve cavity 15, and the second opening 17 communicates with the valve hole portion 11. Along the axial direction of the electric valve 100, the second opening 17 is located on one side of the valve hole portion 11, and the second opening 17 is located on the other side of the valve hole portion 11, so that the flow path does not turn too much. When the valve core 2 opens the valve hole portion 11, the valve hole portion 11 communicates with the first opening 16 and the second opening 17 respectively. The valve core seat 1 can be inserted into the valve body 5, so that the first opening 16 and the second opening 17 communicate with the channels of the valve body 5 respectively, and then the flow rate of a certain flow path in the air-conditioning system is adjusted.

[0062] It should be noted that the working medium in the electric valve 100 can be a refrigerant, such as R134a, R1234yf, and the electric valve 100 can throttle and expand the refrigerant. The working medium in the electric valve 100 can also be a coolant, oil, etc.

[0063] As Figure 11 shown, in other embodiments of the electric valve, the first side wall portion 23 extends along the axial direction of the electric valve 100, and the second side wall portion 12 protrudes inward along the radial direction of the electric valve 100. In the first working state, when the valve core 2 moves a distance greater than zero, the cross-sectional area of the flow channel between the first side wall portion 23 and the second side wall portion 12 is basically constant or within a smaller range, so that the flow rate of the flow channel is within a small flow rate range, which can improve the stability of the electric valve and improve the system efficiency. The cross-section of the second side wall portion 12 can be arc-shaped. Specifically, the axial dimension of the first side wall portion 23 is greater than 4% of the total stroke of the valve core 2, which can further improve the stability of the electric valve and improve the system efficiency.

[0064] As Figure 10 shown, in another embodiment of the electric valve, the second side wall portion 12 extends along the axial direction of the electric valve 100, and the first side wall portion 23 protrudes outward along the radial direction of the electric valve 100. In the first working state, when the valve core 2 moves a distance, the cross-sectional area of the flow channel between the first side wall portion 23 and the second side wall portion 12 is basically constant or within a smaller range, so that the flow rate of the flow channel is within a small flow rate range, which can improve the stability of the electric valve and improve the system efficiency. The cross-section of the first side wall portion 23 can be arc-shaped. Specifically, the axial dimension of the second side wall portion 12 is greater than 4% of the total stroke of the valve core 2, which can further improve the stability of the electric valve and improve the system efficiency.

[0065] It should be noted that "inward" in this application refers to the direction towards the central axis of the valve core 2, and "outward" refers to the direction away from the central axis of the valve core 2.

[0066] In another embodiment of the control method of the electric valve 100, the control method of the electric valve 100 includes: inserting at least a part of the insertion portion 22 into the valve hole of the valve hole portion 11, so that during the process of the insertion portion 22 moving a distance greater than zero, the flow rate of the flow channel is within the small flow rate range, wherein the flow channel is located between the insertion portion 22 and the valve hole portion 11, thereby improving the stability of the electric valve 100.

[0067] In yet another embodiment of the control method of the electric valve 100, the control method of the electric valve 100 includes: inserting at least a part of the insertion portion 22 into the valve hole of the valve hole portion 11, so that during the process of the insertion portion 22 moving a distance greater than zero, the cross-sectional area of the flow channel is within a certain range, wherein the flow channel is located between the insertion portion 22 and the valve hole portion 11, thereby improving the stability of the electric valve 100.

[0068] It should be noted that the above embodiments are only used to illustrate the present invention and do not limit the technical solutions described in the present invention. Although the present specification has described the present invention in detail with reference to the above embodiments, those of ordinary skill in the art should understand that those skilled in the art can still modify the present invention or make equivalent substitutions, and all technical solutions and improvements that do not depart from the spirit and scope of the present invention should be covered within the scope of the claims of the present invention.

Claims

1. An electric valve (100), comprising a valve core seat (1) and a valve core (2), wherein the valve core seat (1) has a valve hole portion (11), the valve core (2) comprises an insertion portion (22), and the electric valve has a valve cavity (15); The electric valve (100) includes at least a first working state. In the first working state, at least a portion of the extending portion (22) is located in the valve hole of the valve hole portion (11). A flow channel is provided between the extending portion (22) and the valve hole portion (11). The flow channel is connected to the valve cavity. When the valve core (2) moves a distance greater than zero, the flow rate of the flow channel is within a small flow rate range.

2. The electric valve according to claim 1, characterized in that: The middle value of the small flow range is 1% to 5% of the full-open flow of the electric valve; The difference between the upper limit and the lower limit of the small flow range is less than 0.5% of the full-open flow of the electric valve.

3. The electric valve according to claim 1 or 2, characterized in that: The electric valve (100) includes a motor assembly (3), the motor assembly (3) includes an output part (34), and the output part (34) is directly or indirectly connected to the valve core (2); the first working state includes a stable flow state, the small flow range is the flow range corresponding to the stable flow state, and the absolute value of the difference between the number of pulses at the beginning of the stable flow state and the number of pulses at the end of the stable flow state is greater than 4% of the fully open pulse number.

4. The electric valve according to claim 3, characterized in that: The fully open pulse number is 400p to 600p, and the pulse number corresponding to the beginning of the stable flow state is in the range of 20p to 100p.

5. The electric valve according to claim 4, characterized in that: The electric valve includes a valve closing state, the pulse number corresponding to the end of the valve closing state is less than the pulse number corresponding to the beginning of the stable flow state, and the pulse number corresponding to the end of the valve closing state ranges from 20p to 60p.

6. An electric valve (100), comprising a valve core seat (1) and a valve core (2), wherein the valve core seat (1) has a valve hole portion (11), the valve core (2) comprises an insertion portion (22), and the electric valve has a valve cavity (15); The electric valve (100) includes at least a first working state. In the first working state, at least a portion of the extending portion (22) is located in the valve hole of the valve hole portion (11). A flow channel is provided between the extending portion (22) and the valve hole portion (11), and the flow channel is connected to the valve cavity. When the valve core (2) moves a distance greater than zero, the cross-sectional area of ​​the flow channel is within a certain range.

7. The electric valve (100) according to claim 6, characterized in that: The flow channel is located at the narrowest part between the extending portion (22) and the valve hole portion (11), the extending portion (22) includes a first side wall portion (23), the first side wall portion (23) is located at the outer periphery of the extending portion (22), and the valve hole portion (11) includes a second side wall portion (12); In the first working state, the second side wall portion (12) surrounds the first side wall portion (23) along the circumference of the electric valve (100), and at least a portion of the first side wall portion (23) is opposite to the second side wall portion (12); The movement direction of the valve core (2) is defined as the axial direction of the electric valve (100), and the first side wall portion (23) and the second side wall portion (12) both extend along the axial direction of the electric valve (100); or, the first side wall portion (23) extends along the axial direction of the electric valve (100), and the second side wall portion (12) protrudes inwardly in the radial direction of the electric valve (100); or, the second side wall portion (12) extends along the axial direction of the electric valve (100), and the first side wall portion (23) protrudes outwardly in the radial direction of the electric valve (100).

8. The electric valve (100) according to claim 7, characterized in that: The radial dimension of the second side wall portion (12) is smaller than the radial dimension of the remaining portion of the valve hole portion (11), the radial dimension of the first side wall portion (23) is larger than the radial dimension of the remaining portion of the extension portion (22), and one of the first side wall portion (23) and the second side wall portion (12) extending axially along the electric valve (100) is cylindrical.

9. The electric valve (100) according to claim 7, characterized in that: The axial dimension of one of the first side wall portion (23) and the second side wall portion (12) extending along the axial direction of the electric valve (100) is greater than 4% of the total stroke of the valve core (2), and the total stroke of the valve core (2) is defined as the stroke of the valve core from closing the valve to fully opening the valve; The cross-sectional area of ​​the flow channel is 1% to 5% of the cross-sectional area of ​​the valve hole.

10. The electric valve (100) according to any one of claims 7 to 9, characterized in that: The valve core seat (1) includes an abutment surface (13), and the abutment surface (13) surrounds the valve hole portion (11). The valve core (2) includes a sealing portion (21), and the sealing portion (21) can abut against the abutment surface (13) to seal the valve hole portion (11); along the axial direction of the electric valve (100), the sealing portion (21) is farther away from the valve hole portion (11) than the extension portion (22).

11. The electric valve (100) according to claim 10, characterized in that: The extending portion (22) includes a first inclined surface (24). Along the axial direction of the electric valve (100), the first inclined surface (24) is farther away from the sealing portion (21) than the first side wall portion (23). The first inclined surface (24) is adjacent to the first side wall portion (23), and the radial dimension of the first inclined surface (24) decreases in a direction away from the sealing portion (21).

12. The electric valve (100) according to claim 11, characterized in that: The first inclined surface (24) is a conical surface, and the axial angle between the first inclined surface (24) and the electric valve (100) is greater than the axial angle between the first side wall portion (22) and the electric valve (100), and the axial angle between the first inclined surface (24) and the electric valve (100) is less than 10°.

13. The electric valve (100) according to claim 12, characterized in that: The protruding portion (22) comprises a second inclined surface (25), and along the axial direction of the electric valve (100), the second inclined surface (25) is farther away from the sealing portion (21) than the first inclined surface (24), the second inclined surface (25) is adjacent to the first inclined surface (24), and the radial dimension of the second inclined surface (25) decreases in a direction away from the sealing portion (21); The second inclined surface (25) is a conical surface, and the angle between the second inclined surface (25) and the axial direction of the electric valve (100) is greater than the angle between the first inclined surface (24) and the axial direction of the electric valve (100).

14. The electric valve (100) according to claim 10, characterized in that: The sealing portion (21) extends outward from the protruding portion (22) along the radial direction of the electric valve (100); the protruding portion (22) comprises a groove (26); along the axial direction of the electric valve (100), the groove (26) is located between the first side wall portion (23) and the sealing portion (21); along the radial direction of the electric valve (100), the groove (26) is recessed inwardly compared to the first side wall portion (23), and the wall forming the groove (26) is adjacent to the sealing portion (21); The valve core seat (1) comprises a convex rib (14) protruding toward the sealing portion (21), the convex rib (14) surrounds the valve hole portion (11), and the abutment surface (13) is located at an end of the convex rib (14) relatively close to the sealing portion (21).

15. The electric valve (100) according to any one of claims 6, 7, 8, 9 to 13, characterized in that: The electric valve comprises a motor assembly (3), the motor assembly (3) comprises a stator assembly (31) and a rotor assembly (32), at least a portion of the stator assembly (31) is located on the periphery of the rotor assembly (32), and the rotor assembly (32) comprises an output portion (34) and a magnetic portion (33); The output part (34) extends along the axial direction of the electric valve (100), and one end of the output part (34) is directly or indirectly connected to the valve core (2); the electric valve (100) includes a nut assembly (4), and the nut assembly (4) is fixedly connected or limit-connected to the valve core seat (1); the output part (34) includes an external threaded part (35), and the nut assembly (4) includes an internal threaded part (41), and the internal threaded part (41) is meshed with the external threaded part (35).

16. A control method for an electric valve (100), the electric valve (100) comprising a motor assembly (3) and a valve core (2), the motor assembly (3) comprising a rotor assembly (32), the rotor assembly (32) comprising an output part (34), the output part (34) being directly or indirectly transmission-connected to the valve core (2); The action direction of the output unit (34) is defined to include a first direction and a second direction, wherein the first direction is opposite to the second direction; The control method of the electric valve (100) comprises: controlling the output portion (34) to move along the first direction so that the rotor assembly (32) reaches a bottom dead point; The output unit (34) is controlled to move along the second direction to a margin interval.

17. A method for controlling an electric valve (100), the method for controlling an electric valve (100) comprising: At least a portion of the extending portion (22) is extended into the valve hole of the valve hole portion (11), so that when the extending portion (22) moves a distance greater than zero, the flow rate of the flow channel is within a small flow rate range, wherein the flow channel is located between the extending portion (22) and the valve hole portion (11).

18. A method for controlling an electric valve (100), the method for controlling an electric valve (100) comprising: At least a portion of the extending portion (22) is extended into the valve hole of the valve hole portion (11), so that when the extending portion (22) moves a distance greater than zero, the cross-sectional area of ​​the flow channel is within a certain range, wherein the flow channel is located between the extending portion (22) and the valve hole portion (11).

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