Flow control valve, thermal management system, air conditioning system and fuel metering system

Abstract

The utility model relates to a flow control valve, a thermal management system, an air conditioning system and a fuel metering system. A flow control valve includes a valve body having an inlet and an outlet and a spool movable in the valve body in an axial direction. A valve seat is arranged at the outlet, the free end of the valve element abuts against the valve seat to close the outlet in the closed position of the flow control valve, a control window is arranged in the inner circumferential wall of the valve body for the inlet, the valve element is provided with a piston section, and the valve element is provided with a piston rod in the closed position of the flow control valve. In a maximum open position of the flow control valve, an outer peripheral wall of the piston section completely covers the control window to prevent fluid flow through the control window, and in a maximum open position of the flow control valve, the outer peripheral wall of the piston section completely releases the control window to enable fluid flow through the control window. The flow control valve not only can control the flow very accurately, but also has very small leakage.

Description

Technical Field

[0001] The present application relates to a flow control valve, a thermal management system having the flow control valve, an air conditioning system having the flow control valve, and a fuel metering system having the flow control valve. Background Art

[0002] A valve is a device used to control the direction, pressure, and flow of a fluid in a fluid system. It is a device that allows the medium (liquid, gas, powder) in the piping and equipment to flow or stop and control its flow. The valve is a control component in the fluid delivery system, with functions such as cutoff, regulation, diversion, backflow prevention, pressure stabilization, diversion or overflow pressure relief. Flow control valves are mainly used for fluid regulation and control in fluid systems. Such flow control valves are also widely used in thermal management systems, air conditioning systems, and fuel metering systems commonly used in the automotive industry. For example, in thermal management systems and air conditioning systems, flow control valves are usually used as expansion valves, which throttle medium-temperature and high-pressure liquid refrigerants into low-temperature and low-pressure wet steam, and then enter the evaporator to absorb heat to achieve a cooling effect. In the fuel metering system, the flow control valve is used to control the precise metering of the fuel, so that emissions that meet regulatory requirements can be obtained.

[0003] There are various types of flow control valves in the prior art. There are two main types: piston valves and seat valves. In a piston valve, the inlet and / or outlet of the valve body is opened or closed by the outer peripheral wall of a valve core configured as a piston. In a seat valve, a valve seat is provided at the outlet, and the outlet is opened or closed by supporting a valve flap provided at the free end of the valve core on the valve seat. Utility Model Content

[0004] However, after research, it was found that in piston valves, there is a large leakage due to the inevitable gap between the inner peripheral wall of the valve body and the outer peripheral wall of the valve core. In seat valves, although the valve disc can be supported on the valve seat to achieve the sealing of the outlet and thus avoid or at least significantly reduce leakage, its flow control effect is poor, especially for small flow control is difficult to be satisfactory.

[0005] Therefore, an object of the present application is not only to improve the flow control effect of the flow control valve, but also to avoid or at least significantly reduce the leakage of the flow control valve.

[0006] According to a first aspect of the present application, a flow control valve is provided, the flow control valve comprising a valve body and a valve core capable of moving in the valve body along the axial direction of the valve body, wherein the valve body has one or more inlets and an outlet. Here, a valve seat is provided at the outlet, and in the closed position of the flow control valve, the free end of the valve core abuts against the valve seat, thereby closing the outlet. In addition, a control window connected to the inlet fluid is provided in the inner peripheral wall of the valve body for each of the inlets, the valve core has a piston section, in the closed position of the flow control valve, the outer peripheral wall of the piston section completely covers the control window, thereby preventing the fluid from flowing through the control window, and in the maximum open position of the flow control valve, the outer peripheral wall of the piston section completely releases the control window, so that the fluid can flow through the control window. The flow control valve combines the advantages of a piston valve and a seat valve, and avoids the disadvantages of the piston valve and the seat valve at the same time. Specifically, the opening and closing of the inlet and the outlet are controlled simultaneously in the flow control valve, that is, the outlet can be closed in the closed position of the flow control valve by adopting the structure of the seat valve, thereby avoiding or at least significantly reducing leakage. The opening and closing of the inlet can be controlled by the piston section of the valve core, and the flow of the flow control valve can be accurately controlled by the control window.

[0007] Optionally, the width of the control window along the circumferential direction of the inner peripheral wall of the valve body remains constant or gradually increases, or first remains constant and then gradually increases, or first gradually increases and then remains constant, or first remains constant and then gradually decreases, or first gradually increases and then gradually decreases as it moves away from the outlet in the axial direction. It should be noted that the above-mentioned variation trend of the width of the control window is only exemplary. According to system requirements, the above-mentioned variation trend can also be changed to obtain the required flow characteristic curve.

[0008] Optionally, when viewed in the radial direction of the valve body, the control window has a triangular or rectangular or semicircular or semi-elliptical shape or a shape having any combination of a triangular, rectangular, semicircular and semi-elliptical shape. In other words, the control window may have a single triangular shape, a single rectangular shape, a single semicircular shape or a single semi-elliptical shape. Alternatively, the control window may also have a shape obtained by any combination of one or more triangles, one or more rectangles, one or more semicircles, or one or more semi-ellipses.

[0009] In an exemplary embodiment, the control window has a shape of a plurality of isosceles triangles that are sequentially adjacent to each other in the axial direction, and the vertex angle of each of the isosceles triangles gradually increases as it moves away from the outlet in the axial direction. In another exemplary embodiment, the control window has a shape of a rectangle and at least one isosceles triangle that are sequentially adjacent to each other in the axial direction, wherein the rectangle is closest to the outlet in the axial direction, and the vertex angle of each of the isosceles triangles gradually increases as it moves away from the outlet in the axial direction.

[0010] In conclusion, the shape of the control window can be reasonably designed according to the requirements for flow control.

[0011] Optionally, the free end of the valve core is formed by a valve flap, and the valve flap is a flat valve flap, a spherical valve flap, or a conical valve flap.

[0012] Optionally, the valve seat is a plane valve seat, a spherical valve seat, or a conical valve seat.

[0013] Here, different shapes of the valve flap and the valve seat can also be combined in any desired manner.

[0014] In the flow control valve, the flow control valve has a driving device for driving the valve core to move along the axial direction, and the driving device can be an electric motor or an electromagnet or a manual operating member.

[0015] According to a second aspect of the present application, a thermal management system is provided, wherein the thermal management system has at least one flow control valve for controlling the flow of a refrigerant.

[0016] According to a third aspect of the present application, an air-conditioning system is provided, wherein the air-conditioning system has at least one flow control valve for controlling the flow of refrigerant.

[0017] According to a fourth aspect of the present application, a fuel metering system is provided, wherein the fuel metering system has at least one flow control valve for controlling the flow of fuel.

[0018] The flow control valve of the present application adopts the valve seat and valve flap of the seat valve, thereby avoiding or at least significantly reducing leakage through the close fit between the valve flap and the valve seat in the closed position of the flow control valve. On the other hand, a piston section is provided on the valve core, so that the control window of the flow control valve is gradually released through the piston section, so that the flow rate can be accurately controlled. By designing the shape of the control window, the desired flow characteristic curve of the flow control valve can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The following will further describe the embodiments of the present application in detail in conjunction with the accompanying drawings, but those skilled in the art will appreciate that these drawings are only used for the purpose of explaining the embodiments and should not be used as a limitation on the scope of the present application. The accompanying drawings show:

[0020] Figure 1 is a schematic diagram of a piston valve in the prior art;

[0021] Figure 2 yes Figure 1 The flow characteristic curve of the piston valve shown;

[0022] Figure 3 is a schematic diagram of a seat valve in the prior art;

[0023] Figure 4 yes Figure 3 The flow characteristic curve of the seat valve shown;

[0024] Figure 5 is a schematic diagram of an implementation of a flow control valve according to the present application;

[0025] Figure 6 is a schematic diagram of an implementation of a control window of a flow control valve according to the present application;

[0026] Figure 7 Is based on Figure 6 The flow characteristic curve of the flow control valve of the control window shown;

[0027] Figure 8 is a schematic diagram of another embodiment of a control window of a flow control valve according to the present application and a corresponding flow characteristic curve;

[0028] Fig. 9 is a schematic diagram of another embodiment of a control window of a flow control valve according to the present application and a corresponding flow characteristic curve;

[0029] Fig.10 It is a schematic diagram of another embodiment of the control window of the flow control valve according to the present application and the corresponding flow characteristic curve. DETAILED DESCRIPTION

[0030] Figure 1A flow control valve 10 in the prior art is shown. The flow control valve 10 is configured as a piston valve. The flow control valve 10 has a valve body 2 and a valve core 1 that can move in the valve body 2 along the axial direction of the valve body 2. In addition, the valve body 2 has two inlets 3 and one outlet 4. Here, the valve core 1 is configured as a piston. The inlet 3 of the valve body 2 is closed or released by the movement of the valve core 1 along the axial direction. However, the outlet 4 of the valve body 2 remains open. Since there is inevitably a gap between the inner circumferential wall of the valve body 2 and the outer circumferential wall of the valve core 1 and the outlet 4 remains open, a large leakage is inevitably present in such a flow control valve 10.

[0031] Figure 2 Shows Figure 1 The flow characteristic curve of the piston valve is shown in FIG. Here, an electrically controlled piston valve is taken as an example. The horizontal axis represents the current I applied to the piston valve, and the vertical axis represents the flow Q through the piston valve. When the power is off, the piston valve remains closed. As the current I increases, the piston overcomes the spring preload and gradually moves upward in the axial direction to release the inlet 3 of the piston valve, thereby gradually increasing the flow Q. However, from Figure 2 It can be seen that when the current I is 0, a certain flow Q is generated, and the flow Q depends on the size of the gap between the inner circumferential wall of the valve body 2 and the outer circumferential wall of the valve core 1.

[0032] Figure 3 A flow control valve 10 in the prior art is shown. The flow control valve 10 is configured as a seat valve. The flow control valve 10 also has a valve body 2 and a valve core 1 that can move in the valve body 2 along the axial direction of the valve body 2. In addition, the valve body 2 has two inlets 3 and an outlet 4. A valve seat 5 is provided at the outlet 4, and in the closed position of the flow control valve 10, the free end of the valve core 1 abuts on the valve seat 5, thereby closing the outlet 4. Here, the valve core 1 is not configured as a piston for closing or releasing the inlet 3, so the inlet 3 of the flow control valve 10 remains open. Although a good sealing of the outlet 4 can be achieved by the free end of the valve core 1 abutting on the valve seat 5, for this flow control valve, it is impossible to achieve a satisfactory flow control effect. In particular, in the stage when the flow control valve 10 is just opened, that is, in the small flow stage, the flow control effect is particularly unsatisfactory.

[0033] Figure 4 Shows Figure 3The flow characteristic curve of the seat valve is shown in FIG. Here, the electrically controlled seat valve is still taken as an example. The horizontal axis represents the current I applied to the seat valve, and the vertical axis represents the flow Q through the seat valve. When no power is applied, the seat valve remains closed. As the current I increases, the valve core 1 gradually moves upward in the axial direction to overcome the spring preload, so that the free end of the valve core 1 gradually lifts from the valve seat 5, thereby gradually opening the seat valve and the flow Q gradually increases. Figure 4 It can be seen that good sealing can be achieved when the current I is 0. However, when the seat valve is just opened, that is, in the small flow stage, the flow Q has a very large increase rate, so the control effect is difficult to be satisfactory.

[0034] Figure 5 is a schematic diagram of a flow control valve 10 according to the present application. The flow control valve 10 comprises a valve body 2 and a valve core 1 which can move in the valve body 2 along the axial direction of the valve body 2, and the valve body 2 has two inlets 3 and one outlet 4. It should be noted that the inlets 3 of the valve body 2 are not limited to two, but may also have only one inlet 3. Of course, three or more inlets 3 may also be provided as required. As shown in the figure, a valve seat 5 is provided at the outlet 4, and in the closed position of the flow control valve 10, the free end of the valve core 1 abuts against the valve seat 5, thereby closing the outlet 4. This design avoids or at least significantly reduces the leakage of the flow control valve 10, because a good seal can be achieved between the free end of the valve core 1 and the valve seat 5. Here, the free end of the valve core 1 is formed by a valve flap, and the valve flap may be a flat valve flap, a spherical valve flap, or a conical valve flap. Accordingly, the valve seat 5 may be a flat valve seat, a spherical valve seat, or a conical valve seat. Here, the different shapes of the valve flap and the valve seat may be arbitrarily combined.

[0035] In addition, a control window 7 in fluid communication with the inlet 3 is provided in the inner peripheral wall of the valve body 2 for each of the inlets 3. The valve core 1 has a piston section 6, and in the closed position of the flow control valve 10, the outer peripheral wall of the piston section 6 completely covers the control window 7, thereby preventing the fluid from flowing through the control window 7, and in the maximum open position of the flow control valve 10, the outer peripheral wall of the piston section 6 completely releases the control window 7, so that the fluid can flow through the control window 7. By designing the shape of the control window 7, the flow rate of the flow control valve 10 can be accurately controlled.

[0036] Here, according to the requirements for flow control, the width of the control window 7 along the circumferential direction of the inner circumferential wall of the valve body 2 can remain constant or gradually increase, or first remain constant and then gradually increase, or first gradually increase and then remain constant, or first remain constant and then gradually decrease, or first gradually increase and then gradually decrease as it moves away from the outlet 4 in the axial direction. It should be noted that the above-mentioned variation trend of the width of the control window is only exemplary. According to system requirements, the above-mentioned variation trend can also be changed to obtain the required flow characteristic curve.

[0037] Observe along the radial direction of the valve body 2, that is, along Figure 5 When viewed in the direction A in the figure, the control window 7 may have a triangular or rectangular or semicircular or semi-elliptical shape, or a shape having any combination of triangular, rectangular, semicircular and semi-elliptical shapes.

[0038] Figure 6 Schematic diagram of an embodiment of the control window of the flow control valve according to the present application. Figure 5 The inlet 3 of the valve body 2 and the contour of the control window 7 and the position of the piston control edge 8 of the piston section 6 relative to the control window 7 when viewed from the A direction in FIG. Here, the shape of the control window 7 is a single isosceles triangle with the top angle pointing downward. Figure 6 It can be seen from the top view that in the closed position of the flow control valve 10, the piston control edge 8 of the piston section 6 is just located at the lower edge of the control window 7, so that the outer peripheral wall of the piston section 6 completely covers the control window 7. Of course, as required, in the closed position of the flow control valve 10, the piston control edge 8 of the piston section 6 can extend downward beyond the lower edge of the control window 7 by a preset distance, so that the outer peripheral wall of the piston section 6 begins to release the control window 7 after the valve core 1 moves upward by the preset distance. Figure 6 The middle view shows that the valve core 1 has moved upward for a certain distance, at which time the piston control edge 8 of the piston section 6 intersects with the two waists of the control window 7, thereby releasing a portion of the control window 7 (the portion below the piston control edge 8) from the outer peripheral wall of the piston section 6. Figure 6 In the bottommost view, the piston section 6 has just passed over the control window 7 , wherein the piston control edge 8 is located at the upper edge of the control window 7 and the outer circumferential wall of the piston section 6 thus completely releases the control window 7 .

[0039] Figure 7 Is based on Figure 6 The flow characteristic curve of the flow control valve with the control window shown in Figure 1 is shown in Figure 2. Figure 7It can be seen that no flow is generated when the current is small. This is because at this time, under the action of the spring preload of the flow control valve, the free end of the valve core 1 is tightly fitted with the valve seat 5. The operating force applied to the valve core 1 (in the case of an electrically controlled flow control valve, it is proportional to the current I applied to the flow control valve 10) first needs to overcome the spring preload applied to the valve core 1. After overcoming the spring preload, the valve core 1 can be lifted from the valve seat 5, and flow begins to be generated. Figure 7 It can be seen that as the current I applied to the flow control valve 10 gradually increases, the flow Q of the flow control valve 10 also gradually increases. Not only does no leakage occur here, but the increase in the flow Q is also relatively gentle compared to the seat valve in the prior art.

[0040] Figure 8 is a schematic diagram of another embodiment of the control window of the flow control valve according to the present application and a corresponding flow characteristic curve. Figure 6 The single isosceles triangle control window shown in the figure adopts a control window formed by two isosceles triangles adjacent to each other, wherein the vertex angle of the triangle located below is smaller than the vertex angle of the triangle located above. Figure 7 Similar flow characteristic curve. Figure 7 The flow characteristic curve is slightly different in that when the piston control edge 8 of the piston section 6 transitions from the lower triangle to the upper triangle, a larger flow change rate can be obtained due to the increase in the change rate of the width of the control window.

[0041] Fig. 9 It is a schematic diagram of another embodiment of the control window of the flow control valve according to the present application and the corresponding flow characteristic curve. Fig. 9 The control window in Figure 8 The difference between the control window in FIG. 1 and FIG. 2 is that an additional rectangular shape is added below the two isosceles triangles. Therefore, when the current I increases to just generate the flow Q, the flow Q has a larger rate of change corresponding to the rectangular shape. After passing through the rectangular section of the control window, the flow characteristic curve is Figure 8 The flow characteristic curves in are basically consistent.

[0042] Fig.10 1 is a schematic diagram of another embodiment of the control window of the flow control valve according to the present application and a corresponding flow characteristic curve. Here, the control window is composed of a single rectangular shape. Thus, after overcoming the spring preload, the flow Q increases linearly with the increase of the current I.

[0043] It should be noted here that in the embodiments described above, the shapes of the control windows of the flow control valves are exemplary. However, the control windows of the flow control valves of the present application are not limited to the above embodiments, but can be reasonably selected and designed according to the requirements of the flow characteristic curve without departing from the spirit of the present application.

[0044] In addition, in the above-described embodiment, the flow rate characteristic curve of the flow control valve is drawn for an electrically controlled flow control valve, that is, the flow control valve has an electromagnet or an electric motor as a driving device. The relationship between the flow rate Q and the current I applied to the flow control valve is drawn here. However, the flow control valve may also be a manually operated flow control valve, that is, the flow control valve has a manual operating member as a driving device. In this case, the current I in the above flow rate characteristic curve can be replaced by an operating force.

[0045] The flow control valve of the present application can be used in a variety of applications. For example, in a thermal management system, especially in a thermal management system for a vehicle, the flow control valve can be used as an expansion valve for controlling the flow of a refrigerant. For another example, in an air-conditioning system, especially in an air-conditioning system for a vehicle, the flow control valve can also be used as an expansion valve for controlling the flow of a refrigerant. In a fuel metering system, especially in a fuel metering system for a vehicle, the flow control valve can be used as a fuel metering valve for controlling the flow of fuel. It should be noted that the above-mentioned applications of the flow control valve are merely exemplary, and the flow control valve of the present application is not limited to the above applications.

[0046] The above is only an exemplary implementation of the present application, and the protection scope of the present application is not limited to the above implementation. All technical solutions under the concept of the present application belong to the protection scope of the present application. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present application should also be regarded as the protection scope of the present application.

Claims

1. A flow control valve (10), comprising: Valve body (2); as well as a valve core (1) capable of moving in the valve body (2) along the axial direction of the valve body (2), Wherein, the valve body (2) has: one or more imports (3); and One exit (4), It is characterized in that A valve seat (5) is provided at the outlet (4), and in the closed position of the flow control valve (10), the free end of the valve core (1) abuts against the valve seat (5), thereby closing the outlet (4). A control window (7) is provided in the inner peripheral wall of the valve body (2) for each inlet (3) and is in fluid communication with the inlet (3). The valve core (1) has a piston section (6), in the closed position of the flow control valve (10), the outer peripheral wall of the piston section (6) completely covers the control window (7), thereby preventing the fluid from flowing through the control window (7), and in the maximum open position of the flow control valve (10), the outer peripheral wall of the piston section (6) completely releases the control window (7), so that the fluid can flow through the control window (7).

2. The flow control valve (10) according to claim 1, characterized in that: The width of the control window (7) along the circumferential direction of the inner circumferential wall of the valve body (2) remains constant or gradually increases, or first remains constant and then gradually increases, or first gradually increases and then remains constant, or first remains constant and then gradually decreases, or first gradually increases and then gradually decreases, as it moves away from the outlet (4) in the axial direction.

3. The flow control valve (10) according to claim 1, characterized in that: When viewed along the radial direction of the valve body (2), the control window (7) has a triangular, rectangular, semicircular, or semi-elliptical shape, or has a shape that is any combination of a triangular, rectangular, semicircular, and semi-elliptical shape.

4. The flow control valve (10) according to claim 3, characterized in that: The control window (7) has a shape of a plurality of isosceles triangles that are sequentially adjacent to each other in the axial direction, and the vertex angle of each isosceles triangle gradually increases as it moves away from the outlet (4) in the axial direction.

5. The flow control valve (10) according to claim 3, characterized in that: The control window (7) has the shape of a rectangle and at least one isosceles triangle which are adjacent to each other in sequence along the axial direction, wherein the rectangle is closest to the outlet (4) along the axial direction, and the vertex angle of each isosceles triangle gradually increases as it moves away from the outlet (4) along the axial direction.

6. The flow control valve (10) according to any one of claims 1 to 5, characterized in that: The free end of the valve core (1) is formed by a valve flap, which is a flat valve flap, a spherical valve flap, or a conical valve flap, and the valve seat (5) is a flat valve seat, a spherical valve seat, or a conical valve seat.

7. The flow control valve (10) according to any one of claims 1 to 5, characterized in that: The flow control valve (10) has a driving device for driving the valve core (1) to move along the axial direction, and the driving device is an electric motor or an electromagnet or a manual operating member.

8. A thermal management system, characterized in that: The thermal management system comprises at least one flow control valve (10) according to any one of claims 1 to 7 for controlling the flow of the refrigerant.

9. An air conditioning system, characterized in that: The air conditioning system comprises at least one flow control valve (10) according to any one of claims 1 to 7 for controlling the flow of a refrigerant.

10. A fuel metering system, characterized in that: The fuel metering system comprises at least one flow control valve (10) according to any one of claims 1 to 7 for controlling the flow of fuel.

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