CN220354602U - Valve device - Google Patents

Abstract

The application provides a valve device, which comprises a sleeve, a rotor component, a magnetic component and a detection component, wherein the detection component is used for detecting the magnetic pole change of the magnetic component; the rotor part is at least partially positioned in the sleeve, the magnetic part comprises a magnet and a connecting sleeve, the magnet is sleeved outside the connecting sleeve and is fixedly or limitedly connected with the connecting sleeve, the connecting sleeve is provided with at least one limiting rod extending along the axial direction, the rotor part is connected with a rotating shaft of the valve device through a connecting part, the connecting part is provided with a limiting hole, and the limiting rod is inserted into the limiting hole, so that the magnetic part and the rotor part synchronously rotate; the inner surface of the top wall of the sleeve is provided with a limiting part, one of the magnetic part and the limiting part is provided with a radially extending protrusion, the other is provided with an annular groove part, and at least part of the protrusion is positioned in the annular groove part to axially limit; or, the limiting component comprises a bearing, an inner ring of the bearing is fixedly connected with the inner surface of the top wall of the sleeve, and an outer ring of the bearing is fixed with the connecting sleeve. This structure is advantageous in simplifying the mounting structure of the magnetic component.

Description

Valve device

Technical Field

The utility model relates to the technical field of valves, in particular to a valve device.

Background

Valve devices such as electronic expansion valves are provided with a drive motor comprising a rotor part and a magnet for detection, which rotates in synchronization with the rotor part, while hall sensors are provided, which can obtain the rotation angle of the magnet by detecting the change in the magnetic field of the magnet, and thus learn the rotation angle of the rotor part.

However, in some valve devices, when the rotor component moves axially, the magnet moves together with the rotor component, at this time, the distance between the hall sensor and the magnet changes, once the distance between the hall sensor and the magnet is larger than a certain value, the magnetic field induced by the hall sensor weakens, so that the hall sensor may not detect the change of the magnetic field signal, thereby affecting the reliability of the detection result, and at present, a scheme of axially limiting the magnet by axially propping the spring exists, but the rotation of the magnet is affected by the propping of the spring, thereby affecting the detection precision.

Disclosure of Invention

The present utility model provides a valve device which is beneficial to simplifying the installation structure of a magnetic component.

The application provides a valve device, comprising a sleeve, a rotor component, a magnetic component and a detection component, wherein the detection component is used for detecting the magnetic pole change of the magnetic component; the rotor part is at least partially positioned in the sleeve, the magnetic part comprises a magnet and a connecting sleeve, the magnet is sleeved outside the connecting sleeve and is fixedly or limitedly connected with the connecting sleeve, the connecting sleeve is provided with at least one limiting rod extending along the axial direction, the rotor part is connected with a rotating shaft of the valve device through a connecting part, the connecting part is provided with a limiting hole, and the limiting rod is inserted into the limiting hole to enable the magnetic part and the rotor part to synchronously rotate;

the inner surface of the top wall of the sleeve is provided with a limiting part, one of the magnetic part and the limiting part is provided with a radially extending protrusion, the other is provided with an annular groove part, and at least part of the protrusion is positioned in the annular groove part to axially limit; or, the limiting component comprises a bearing, the inner ring of the bearing is fixedly connected with the inner surface of the top wall of the sleeve, and the outer ring of the bearing is fixed with the connecting sleeve.

The valve device of the application is provided with the limiting component, and the annular groove is arranged by the limiting component and matched with the annular bulge of the magnetic component to limit the axial movement of the magnetic component, or the axial movement is limited by the bearing, so that the valve device is beneficial to simplifying the installation structure of the magnetic component.

Drawings

FIG. 1 is a schematic view showing a part of the structure of a valve device in a first embodiment of the present application;

FIG. 2 is a schematic view of the spacing member of FIG. 1;

FIG. 3 is a schematic radial cross-sectional view of the stop member and magnetic member, spindle position of FIG. 2.

FIG. 4 is a schematic diagram of the pole distribution of the rotor and magnet assemblies of FIG. 1;

FIG. 5 is a schematic diagram of magnetizing an axial surface of a magnetic component of the present application;

FIG. 6 is a schematic view showing a part of the construction of a valve device in a second embodiment of the present application;

FIG. 7 is a schematic view of the spacing member of FIG. 7;

FIG. 8 is a schematic radial cross-sectional view of the stop member and magnetic member, spindle position of FIG. 7.

The reference numerals in fig. 1-8 are illustrated as follows:

1-rotor component

2-magnetic parts; 21-a magnet; 22-connecting sleeve; 221-annular protrusion; 222-a limit rod;

3-rotating shaft;

4-a limiting component; 41-limiting a base; 411-a first annular flange; 41 a-an inner bore; 41 b-an annular clamping groove; 42-lining; 421-a second annular flange; 43-check ring; 4 a-an annular groove portion;

a 5-connection; 5 a-a limiting hole;

6-stator parts;

100-a circuit board; 200-detecting means; 300-sleeve.

Detailed Description

In order to better understand the aspects of the present utility model, the present utility model will be described in further detail with reference to the accompanying drawings and detailed description.

Referring to fig. 1-3, fig. 1 is a schematic view of a part of a valve device according to a first embodiment of the present application; fig. 2 is a schematic view of the limiting member 4 in fig. 1; fig. 3 is a schematic radial sectional view of the position of the limiting member 4, the magnetic member 2 and the rotating shaft 3 in fig. 2.

The present embodiment provides a valve device, for example, an electronic expansion valve, a ball valve, or a water valve, where the valve device includes a sleeve 300, a rotating shaft 3, a stator component 6, and a rotor component 1, where the stator component 6 is sleeved on the outer periphery of the sleeve 300, at least a part of the rotor component 1 is located in the sleeve 300, the stator component 6 generates a magnetic field, and the rotor component 1 rotates under excitation to drive the rotating shaft 3 to rotate, and the rotating shaft 3 can be connected with a valve core component of the valve device, so as to drive the valve core component to act to perform opening adjustment or switching adjustment of a valve port, and the present embodiment mainly uses an electronic expansion valve as an example.

The rotor part 1 and the rotating shaft 3 in this embodiment are connected in a switching way or in an indirect way, and the connection mode can be a fixed connection or a limiting connection, so that the rotor part 1 and the rotating shaft 3 can rotate synchronously. In the embodiment shown in fig. 1, the rotor part 1 is connected in particular by means of a magnetic part 2 and a rotational shaft 3, and in the embodiment shown in fig. 1, the rotor part 1 is connected in particular by means of a connection 5, in particular a connection plate, to the rotational shaft 3.

As shown in fig. 1, the valve device in this embodiment includes a magnetic member 2, and the valve device further includes a detecting member 200, where the magnetic member 2 is used for detecting the detecting member 200, and when the magnetic member 2 rotates with the rotor member 1, the detecting member 200 senses a magnetic pole change of the magnetic member 2, and according to the magnetic pole change, a rotation angle of the magnetic member 2 can be obtained, and as the magnetic member 2 rotates with the rotor member 1 synchronously, a rotation parameter of the rotor member 1 can be obtained accordingly, and then parameters such as a rotation speed, a position, a locked rotor, and a step out of the rotor member 1 in the valve device are obtained. In fig. 1, the detecting member 200 is provided above the magnetic member 2, or may be located directly above or offset from the magnetic member 2 to sense a change in the magnetic pole of the magnetic member 2.

The valve device is provided with a housing (not shown in the drawings), and as shown in fig. 1, the valve device may be further provided with a circuit board 100, a detection part 200 is provided on the circuit board 100, the detected signal may be directly transmitted and processed by the circuit board 100, and the circuit board 100 is provided outside the sleeve 300 and inside the housing of the valve device.

It should be noted that, the sleeve 300 in this embodiment includes a cylindrical side wall 302 and a top wall 301, and the inner surface of the top wall 301 is provided with a limiting member 4 for axially limiting the magnetic member 2 and limiting the axial movement of the magnetic member 2. As shown in fig. 1 and 2, the limiting member 4 is disposed on the inner surface of the top wall 301 of the sleeve 300, the limiting member 4 specifically includes a limiting base 41 and a bushing 42, the limiting base 41 specifically is a bushing structure shown in fig. 2, the limiting base 41 has a hole portion 41a, the hole portion 41a may be a blind hole structure or a through hole structure, when the hole portion 41a is a blind hole, the bottom portion thereof is opened, the top portion of the limiting base 41 has a larger area, and the limiting base 41 may be fixed to the top wall 301 of the sleeve 300, and may be fixed to the top wall 301 by welding, fastening by a fastener, or the like, and the welding may be resistance welding, rivet welding, or the like. As used herein, "top" and "bottom" refer to the top and bottom sides of the top wall 301, respectively, and the inner surface of the top wall 301 is also the bottom surface of the top wall 301, respectively, in the axial direction from the perspective of fig. 1.

The bottom of the limit base 41 has a first annular flange 411 extending radially outwardly, here outwardly, i.e. away from the central axis of the limit base 41. The bushing 42 has a through hole portion, and the bushing 42 is sleeved on the outer periphery of the limit base 41, and can be in interference fit with the limit base 41, however, the two can be in clearance fit. The bottom of the bushing 42 is supported on the first annular flange 411, the top of the bushing 42 has a second annular flange 421, the second annular flange 421 being formed by the radially outward extension of the top of the bushing 42, where the second annular flange 421 may be in contact with the top wall 300 of the sleeve 300, i.e. away from the central axis of the bushing 42, in which case an annular groove 4a is formed between the first annular flange 411 and the second annular flange 421.

With continued reference to fig. 1, the magnetic component 2 includes a connecting sleeve 22 and a magnet 21, where the magnet 21 is sleeved on the periphery of the connecting sleeve 22, and can be fixed with the connecting sleeve 22 by injection molding, or can be connected with the connecting sleeve 22 in a limiting manner, for example, the connecting sleeve 22 and the magnet 21 are clamped, so that the magnet 21 can rotate synchronously with the connecting sleeve 22. The part of the wall of the sleeve hole of the connecting sleeve 22 extends radially inwards to form an annular protrusion 221, specifically in fig. 1, the upper end of the wall of the connecting sleeve 22 extends radially inwards to form an annular protrusion 221, the connecting sleeve 22 is sleeved with the limiting member 4 radially inwards, namely in the direction close to the center of the connecting sleeve 22, and the annular protrusion 221 is inserted into the annular groove part 4a of the limiting member 4.

So arranged, as shown in fig. 1, the magnetic member 2 is caught between the first annular flange 411 and the second annular flange 421 by the annular protrusion 221, and the magnetic member 2 cannot move axially. In the valve device in which the rotor member 1 moves in the axial direction and also rotates, the magnetic member 2 does not move in the axial direction when the rotor member 1 and the rotating shaft 3 move in the axial direction, and of course, in the valve device in which the rotor member 1 only rotates, even if the rotor member 1 may move in the axial direction to some extent, the distance between the detecting member 200 and the magnetic member 2 can be kept constant, the strength of the magnetic field change sensed by the detecting member 200 when the magnetic member 2 rotates is not changed, thereby ensuring the detection accuracy, and the limiting member 4 has a simple structure and reliably limits the magnetic member 4.

In addition, the limiting member 4 is arranged in a manner convenient for assembly. As shown in fig. 1, the limit base 41, the bushing 42, and the magnetic member 2 may be pre-assembled and then secured to the top wall 301 of the sleeve 300. The process of assembly is, for example, that the limit base 41 is penetrated upwards from the bottom of the magnetic component 2, the bushing 42 is inserted downwards from the top, or the magnetic component 2 and the bushing 42 are assembled (for example, the connecting sleeve 22 and the bushing 42 are in interference press fit), the limit base 41 is penetrated again from the bottom, and then the limit base 41 and the top wall 301 are welded and fixed. Therefore, the components are arranged in a split mode, and the processing is simple and the assembly is convenient. When the magnetic component 2 and the bushing 42 are in clearance fit, the magnetic component 2 can be made of wear-resistant and relatively smooth materials, so that the magnetic component 2 can rotate conveniently; the limit base 41 can also be made of wear-resistant and relatively smooth materials, and the limit base 41 is smoother when the bushing 42 and the limit base 41 rotate relatively. That is, the magnetic component 2 in this embodiment may rotate relative to the bushing 42, or may rotate as a whole relative to the limit base 41 after being press-fitted and fixed with the bushing 42.

However, it is obvious that the structure of the limiting member 4 is not limited thereto, and the limiting member 4 may be formed by vertically butting two members, and the annular groove portion 4a may be formed after butting, and may be formed by assembling one member and the magnetic member 2 and then butting. For another example, the limiting component 4 may also be a bearing, the magnetic component 2 is connected with an outer ring of the bearing, for example, the connecting sleeve 22 is fixed with the outer ring of the bearing, the connecting sleeve 22 and the outer ring of the bearing may be in interference fit, adhesion or fastening by a fastener, etc., the inner ring of the bearing is fixedly connected with the top wall 301 of the sleeve 300, so that axial limiting can be achieved as well, and the connecting sleeve 22 can rotate.

In this embodiment, the magnetic component 2, the rotor component 1 and the rotating shaft 3 rotate synchronously, but when the rotor component 1 and the rotating shaft 3 move axially, the axial position of the magnetic component 2 remains unchanged, one end of the rotating shaft 3 can be inserted into the hole 41a of the limiting base 41 and can be in clearance fit with the hole 41a, as shown in fig. 3, the rotating shaft 3 is a circular shaft, the hole 41a of the limiting base 41 is a circular hole, and the limiting base 41 can play a role in guiding the axial movement of the rotating shaft 3, so that the coaxiality of a product is improved. Of course, the rotation shaft 3 may not extend into the limit base 41, in other words, the limit base 41 does not need to be provided with the hole portion 41a, that is, the limit base 41 of the limit member 4 sleeved by the bushing 42 is not limited to the limit base 41 provided with the hole portion 41a, and for example, the limit base may be a cylindrical structure.

With continued reference to fig. 1, the connecting sleeve 22 of the magnetic component 2 is provided with a limiting rod 222 extending along the axial direction, the connecting portion 5 of the rotor component 1 and the rotating shaft 3 is provided with a limiting hole portion 5a, the limiting rod 222 is inserted into the limiting hole portion 5a, and the rotating shaft 3 can drive the connecting sleeve 22 to rotate when rotating, and accordingly, the magnetic component 2 can be driven to rotate. At least one limiting rod 222 can be arranged, two or more limiting rods 222 can be radially symmetrically arranged, and more than two limiting rods 222 are uniformly distributed along the circumferential direction, so that the stress can be balanced. The length of the limiting rod 222 extending out of the limiting hole part 5a should be satisfied, and in the axial movement stroke of the rotating shaft 3, the limiting rod 222 will not separate from the limiting hole part 5a, so as to ensure that the rotating shaft 3 can always drive the magnetic component 2 and the rotor component 1 to synchronously rotate.

In this embodiment, the magnetic component 2 is provided with the connecting sleeve 22, so that the magnet 21 made of magnetic material and the rotating shaft 3 are indirectly connected to realize synchronous rotation, and the relative rotation of the bushing 42 or the limiting base 41 of the relative limiting component 4 is facilitated.

It is noted that the above-described rotor member 1 includes a plurality of pairs of first magnetic poles 1a distributed in the circumferential direction and magnetized in the radial direction, and the magnet 21 of the magnetic member 2 includes one or more pairs of second magnetic poles 21a distributed in the circumferential direction and magnetized in the axial direction. I.e. the direction of magnetization of the rotor part 1 and the magnet 21 is perpendicular, and accordingly the magnetic field distribution of the rotor part 1 and the magnet 21 is different.

As can be understood with continued reference to fig. 4, 5, fig. 4 is a schematic diagram of the magnetic pole distribution of the rotor part 1 and the magnet 21 of fig. 1; fig. 5 is a schematic diagram of magnetizing an axial surface of a magnetic component of the present application.

Here, the axial surface magnetization defines, on the one hand, that the magnetization direction is axial and, on the other hand, that the magnetization is surface magnetization, which requires that the magnet 21 has a magnetic field on the side in the axial direction toward the detection member 200 and has no magnetic field on the other side away from the detection member 200. As shown in fig. 5, in order to magnetize the axial surface, the magnetizing tool 01 only arranges the iron core 012 and the energizing coil 011 on one axial side of the magnet 21, and generates a strong magnetic field by the N pole and the S pole to magnetize the surface of the magnet 21, and by controlling the distance between the magnetizing tool 01 and the surface of one side of the magnet 21, the magnetizing range of the magnet 21 can be controlled so that the other side after magnetizing has no magnetic field, i.e. the magnetic field is zero, or the magnetic field is weak. The magnetizing tool 01 shown in fig. 5 includes an iron core 012 and an energizing coil 011, which is only a specific way, and may be magnetized by a strong magnet. After magnetizing, the magnet 21 may be detected by the magnetic field induction component after machining, and the magnetic field may not be detected at the other side away from the detection component 200, or the magnetic field strength may be within a weaker range, which may be considered that the magnet 21 satisfies the purpose of magnetizing the axial surface.

In fig. 4, the rotor member 1 includes at least one pair of radially magnetized first magnetic poles 1a. The first poles 1a of each pair comprise N and S poles and the rotor member 1 is a radially magnetized magnetic sleeve, and the magnetic field lines of the adjacent pair of first poles 1a are directed from the N pole to the S pole in a radial plane, as can be appreciated with reference to the closed magnetic field lines with arrows in fig. 4.

In fig. 4, the magnet 21 of the magnetic member 2 includes at least a pair of second magnetic poles 2a magnetized to the axial surface, the second magnetic poles 2a being distributed in the circumferential direction. Each pair of second magnetic poles 2a includes an N pole and an S pole, and the magnet 21 is an axially magnetized magnetic ring, so that magnetic lines of force of the adjacent pair of second magnetic poles 12a are directed from the N pole to the S pole in an axial plane, which can be understood by referring to closed magnetic lines of force with arrows in fig. 4.

At this time, when the magnet 21 and the rotor member 1 rotate synchronously, the magnetic field strength sensed by the detecting element 200 will change, and the detecting element 200 can obtain the rotation parameter of the magnet 21 by detecting the change of the magnetic field, and accordingly obtain the rotation parameter of the rotor member 1, and then obtain the rotation speed, position, locked rotation, and out-of-step parameters of the rotor member 1 in the valve device.

In this embodiment, the magnetic component 2 used for detecting by the detecting component 200 is that the axial surface is magnetized, the magnetizing directions of the magnet 21 and the rotor component 1 are perpendicular to each other, the magnetic field of the magnetic component 2 does not affect and interfere with the work of the rotor component 1, and no axial pulling force is generated, and because of the axial surface magnetization, the detecting component 200 can be arranged on one axial side of the magnetic component 2 as shown in fig. 1 and 5, and is not required to be arranged on one radial side of the rotor component 1 through a fixing bracket, so that the detecting component 200 in this embodiment is not required to be fixed on the circuit board 100 through the fixing bracket, and can be directly mounted on the circuit board 100 in a patch manner, thus the detection precision requirement can be met in terms of the axial detection manner, automatic patch mounting can be performed during production, and the production efficiency is improved. Further, as described above, the magnetic member 2 in this embodiment can be kept unchanged in axial position by the elastic member, thereby ensuring the detection accuracy of the detection member 200.

The magnet 21 may be multipolar to be magnetized, that is, includes a plurality of pairs of second magnetic poles 2a, so that the frequency of the magnetic field change is high during the rotation of the magnet 21, and the detection accuracy is high, and the detection component 200 may employ a switch hall sensor, which has low cost and typically has three pins, and can be attached to the surface of the circuit board 100, and fixed to the circuit board 100 in particular by soldering. The principle of the switch Hall sensor is as follows: when carriers in the material of the base material of the switch Hall sensor move in an externally applied magnetic field, the tracks are deviated due to the action of Lorenter magnetic force, and charge accumulation is generated at two sides of the base material to form an electric field perpendicular to the current direction, so that potential difference, namely Hall voltage, is established at two sides, the size of the Hall voltage is in direct proportion to the magnetic field, the change of the magnetic field can be fed back through the change of the Hall voltage, and then the rotating parameters such as the rotating speed, the rotating angle and the like of the magnet 21 are converted.

Because the magnetic component 2 used for detecting by the detecting component 200 in this embodiment is that the axial surface is magnetized, the magnetizing direction of the magnet 21 and the rotor component 1 is perpendicular, the magnetic field of the magnetic component 2 will not affect and interfere with the work of the rotor component 1, so that the magnetic component 2 can be magnetized in multiple poles, in this way, the magnetic field change frequency in the rotating process of the magnetic component 2 is higher, the detecting precision is higher, at this time, the detecting element 200 can be a switch hall sensor, the cost of components is lower, and automatic pasting can be performed during production, thereby improving the production efficiency. Of course, the magnetic component 2 can also be multipolar radial magnetization, and only an in-line hall sensor can be adopted at this time, so that the cost is relatively high.

With continued reference to fig. 6-8, fig. 6 is a schematic view of a portion of a valve device according to a second embodiment of the present application; fig. 7 is a schematic view of the limiting member 4 in fig. 6; fig. 8 is a schematic radial sectional view of the position of the limiting member 4, the magnetic member 2 and the rotating shaft 3 in fig. 7.

This embodiment is basically the same as the first embodiment except that in the second embodiment, the stopper member 4 includes a stopper base 41 and a retainer ring 43, the stopper base 41 is the same as the stopper base 41 in the first embodiment, the retainer ring 43 functions similarly to the bushing 42 in the first embodiment, the retainer ring 43 is stuck outside the upper end portion of the stopper base 41, an annular catching groove 41b may be provided outside the upper end portion of the stopper base 41, the retainer ring 43 may be stuck into the annular catching groove 41b based on a certain deformability, in this way, an annular groove portion 4a is formed between the retainer ring 43 and the first annular flange 411 of the stopper base 41, the annular protrusion 221 of the connecting sleeve 22 of the magnetic member 2 is located in the annular groove portion 4a, so that the magnetic member 2 is axially stopped, the annular protrusion 221 is inserted into the annular groove portion 4a and is in clearance fit with the annular groove portion 4a, and the connecting sleeve 22 can freely rotate relative to the stopper base 41. It is known that the retainer ring 43 is provided at the bottom of the limit base 41, and the upper end of the second bushing 41 may be provided with a first annular flange extending radially outward, or it is also possible that both the top and bottom of the second bushing 41 are engaged with the retainer ring 43, and an annular groove 4a is formed between the two retainer rings 43. It will be appreciated that during assembly, the connecting sleeve 22 is assembled with the limit base 41, and then the retainer ring 43 is clamped into the limit base 41, and the connecting sleeve 22 in the limit component 4 is not illustrated in fig. 7, so as to understand the formed annular clamping groove 41b.

The configuration of the rest of the second embodiment is the same as that of the first embodiment, and will not be described again.

It should be understood that in the first embodiment and the second embodiment, the limiting member 4 and the magnetic member 2 are axially limited by providing the annular groove portion 4a and the annular protrusion 221, and it is also possible that the connecting sleeve 22 of the magnetic member 2 is provided with an annular groove portion and the annular protrusion is provided on the limiting member 4. In practice, the axial limitation is not limited to the cooperation between the annular protrusion 221 and the annular groove portion 4a, for example, the connecting sleeve 22 is provided with a plurality of protrusions distributed along the circumferential direction, and the protrusions may be inserted into the annular groove portion 4a, that is, the protrusions need not be annular.

Specific examples are set forth herein to illustrate the principles and embodiments of the present application, and the description of the examples above is only intended to assist in understanding the methods of the present application and their core ideas. It should be noted that it would be obvious to those skilled in the art that various improvements and modifications can be made to the present application without departing from the principles of the present application, and such improvements and modifications fall within the scope of the claims of the present application.

Claims (8)

1. A valve device, characterized by comprising a sleeve (300), a rotor part (1), a magnetic part (2) and a detection part (200), the detection part (200) being used for detecting a magnetic pole change of the magnetic part (2); the rotor component (1) is at least partially positioned in the sleeve (300), the magnetic component (2) comprises a magnet (21) and a connecting sleeve (22), the magnet (21) is sleeved outside the connecting sleeve (22) and is fixedly or limitedly connected with the connecting sleeve (22), the connecting sleeve (22) is provided with at least one limiting rod (222) extending along the axial direction, the rotor component (1) is connected with a rotating shaft (3) of the valve device through a connecting part (5), the connecting part (5) is provided with a limiting hole (5 a), and the limiting rod (222) is inserted into the limiting hole (5 a) to enable the magnetic component (2) and the rotor component (1) to synchronously rotate;

the inner surface of the top wall (301) of the sleeve (300) is provided with a limiting part (4), one of the magnetic part (2) and the limiting part (4) is provided with a radially extending protrusion, the other is provided with an annular groove part (4 a), and at least part of the protrusion is positioned in the annular groove part (4 a) to axially limit; or, the limiting component (4) comprises a bearing, the inner ring of the bearing is fixedly connected with the inner surface of the top wall (301) of the sleeve (300), and the outer ring of the bearing is fixedly connected with the connecting sleeve (22).

2. Valve device according to claim 1, wherein the limit element (4) comprises a limit base (41) and a bushing (42), the top of the limit base (41) is fixedly connected with the inner surface of the top wall of the sleeve (300), the bottom of the limit base (41) is provided with a first annular flange (411) extending radially outwards, the bushing (42) is provided with a through hole, the limit base (41) is at least partially located in the through hole, the top of the bushing (42) is provided with a second annular flange (421) extending radially outwards, and the annular groove (4 a) is formed between the first annular flange (411) and the second annular flange (421).

3. Valve device according to claim 2, characterized in that the bushing (42) and the limit seat (41) are interference fit.

4. The valve device according to claim 1, wherein the limit member comprises a limit base, the top of which is fixedly connected to the inner surface of the top wall of the sleeve (300); the limiting part also comprises a retainer ring (43);

one of the top and the bottom of the limit base is provided with a first annular flange (411) extending outwards in a radial direction, the other is clamped with a check ring (43), and the annular groove part (4 a) is formed between the first annular flange (411) and the check ring (43); or, the top and the bottom of the limiting component are respectively provided with a retaining ring (43), and an annular groove part (4 a) is formed between the two retaining rings (43).

5. Valve device according to any one of claims 2-4, characterized in that the limit base (41) has a hole, an end of the rotating shaft (3) of the valve device being inserted into the hole of the limit base (41).

6. Valve device according to any of claims 2-4, wherein the limit base (41) and the inner surface of the top wall of the sleeve (300) are welded or fastened by means of fasteners.

7. Valve device according to any of claims 1-4, characterized in that the connecting sleeve (22) is provided with two or more limit rods (222), a plurality of limit rods (222) being evenly distributed around the rotation axis (3) of the valve device.

8. A valve arrangement according to any one of claims 1-4, wherein the rotor part (1) comprises a plurality of pairs of circumferentially distributed and radially magnetized first poles, and the magnet (21) comprises at least one pair of circumferentially distributed and axially surface magnetized second poles.