A pilot type electronic expansion valve structure

Abstract

This invention discloses a pilot-operated electronic expansion valve structure, including a hydraulic component and an electrical component. The hydraulic component includes a fixed valve seat, inside which a valve sleeve is fixedly installed. The inner cavity of the valve sleeve houses a drive valve core, a spring, and a push rod. A pressure outlet chamber is provided on the fixed valve seat, and a pressure inlet chamber is provided between one end of the fixed valve seat and the drive valve core. A pressure chamber is provided between the push rod and the drive valve core. The electrical component drives the push rod to control the opening and closing of the secondary valve, thereby adjusting the pressure within the pressure chamber and changing the pressure on the drive valve core to indirectly control the opening and closing of the main valve. This invention effectively solves the problem of low output flow rate and also addresses the issue that the force or torque generated by the coil and internal structure cannot overcome the internal medium pressure when increasing the flow output. It meets the needs of automotive thermal management systems with a wide range of flow requirements, featuring a simple structure, low cost, and strong practicality.

Description

Technical Field

[0001] This invention relates to the technical field of automotive thermal management systems, specifically to a pilot-operated electronic expansion valve structure. Background Technology

[0002] This invention relates to automotive thermal management systems, such as those for automotive heat pump air conditioning. In situations where load changes are drastic or operating conditions are wide-ranging, existing expansion valves can no longer meet the comfort and energy-saving requirements under different conditions. Therefore, developing an electronic expansion valve that can meet the needs of various operating conditions is urgently needed. When this electronic expansion valve is in operation, it uses a coil to supply an electrical signal, generating a magnetic field. Under the influence of this magnetic field, the armature drives a push rod, overcoming the pressure generated by the medium and internal structural forces (such as spring force) to move axially, thereby controlling the opening and closing of the internal position.

[0003] In automotive thermal management systems, the flow output requirements of electronic expansion valves vary depending on the operating conditions. Under certain conditions, a small flow output is needed, while under others, a large flow output is required. Conventional applications involve using two or more electronic expansion valves in the system to accommodate these varying needs, resulting in high costs. Among known solutions, one type of electronic expansion valve uses a coil to directly drive the opening and closing of its internal position. However, this method results in a small flow output. When the flow output is increased, the force or torque generated by the coil and internal structure cannot overcome the internal medium pressure, thus failing to meet the needs of refrigeration systems with a wide range of flow requirements. Another type is the deceleration-type electronic expansion valve, as described in the patent application CN202210668410.8, which amplifies the torque through an internal reduction gear to overcome the internal medium pressure. However, this type of valve has a complex structure, high control requirements, weak resistance to foreign objects, and a slow response time.

[0004] No solutions have yet been proposed for the relevant technical issues. Summary of the Invention

[0005] To address the problems in related technologies, this invention proposes a pilot-operated electronic expansion valve structure to overcome the aforementioned technical issues in existing technologies. The purpose of this invention is to effectively solve the problem of low output flow rate, and at the same time, to solve the problem that the force or torque generated by the coil and internal structure cannot overcome the internal medium pressure when increasing the flow rate output. This results in a thermal management system that effectively meets the needs of a wide range of flow rates. The system is simple in structure, low in cost, and easy to use.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a pilot-operated electronic expansion valve structure, comprising a hydraulic component and an electrical component. The hydraulic component includes a fixed valve seat, inside which a valve sleeve is fixedly installed. The inner cavity of the valve sleeve is provided with a drive valve core, a spring, and a push rod. The two ends of the spring are respectively connected to the drive valve core and the valve sleeve. The push rod is connected to the electrical component. The fixed valve seat has a pressure outlet chamber. A pressure inlet chamber is provided between the fixed valve seat and one end of the drive valve core. A pressure chamber is provided between the push rod and the drive valve core. A pressure relief channel is provided on the right side of the valve sleeve. A main opening / closing mechanism is provided between the pressure outlet chamber and the pressure inlet chamber. A secondary opening / closing mechanism is provided between the pressure chamber and the pressure relief channel. A pressure supply channel is provided on the drive valve core. The electrical component includes a coil, inside which a sleeve is provided. An armature is provided inside the sleeve. The armature is fixedly connected to a guide thread. A guide sleeve is also installed inside the valve sleeve. A threaded pair is provided between the guide sleeve and the guide thread. The fixed valve seat has an oil passage connecting to the external environment. The oil passage includes a first channel and a second channel. The pressure outlet chamber and the pressure relief channel can be connected to the external environment through the first channel or the second channel. The opening and closing position of the second channel is located at the auxiliary opening and closing position. The auxiliary opening and closing position is located on the valve sleeve. The armature inside the electrical component is affected by the magnetic field after the coil is energized, which drives the push rod to move axially continuously. By changing the magnetic field after energization, the push rod can be kept at any position within the preset stroke. The distance between the push rod and the auxiliary opening and closing position is called the opening degree of the auxiliary opening and closing position. The flow rate of the medium flowing from the hydraulic component to the external environment through the second channel is directly controlled by the opening degree of the auxiliary opening and closing position. By adjusting the magnetic field generated by the coil, the opening degree of the auxiliary opening and closing position within the preset range can be adjusted so that the flow rate through the second channel can be kept at any size within the preset range. This adjustment process is called small flow rate proportional adjustment.

[0007] Preferably, when the auxiliary opening and closing is closed, the pressure of the medium in the pressure inlet chamber can be transmitted to the interior of the pressure chamber, and the pressure in the pressure inlet chamber and the pressure chamber are equal; when the auxiliary opening and closing is open, the pressure of the medium in the pressure inlet chamber and the pressure of the medium in the pressure chamber are released through the pressure relief channel, and the pressure in the pressure chamber is reduced.

[0008] Preferably, the opening and closing functions of the secondary switch are related to the pressure decrease and increase inside the pressure chamber, leading to the final opening and closing functions of the main switch.

[0009] Preferably, a sealing gasket is installed on the end face of the valve sleeve, and a sealing ring is installed between the fixed valve seat and the valve sleeve.

[0010] Preferably, the first channel of the electronic expansion valve is located at the main opening / closing position. The pressure inside the pressure chamber is adjusted by the opening degree of the secondary opening / closing, and the pressure and spring force at both ends of the drive valve core change, causing the drive valve core to move away from or close to the main opening / closing position, thereby realizing the opening and closing of the main opening / closing. By preset spring force and pressure on the drive valve core, the opening degree of the secondary opening / closing exists at a certain critical position. Between the preset initial position and the critical position, the pressure applied to the drive valve core in the pressure chamber plus the spring force is greater than the pressure in the inlet pressure chamber on the drive valve core. During this period, only the second channel participates in flow output, and the electronic expansion valve can achieve preset small-range proportional flow adjustment. When the push rod moves from the critical position to the preset termination position, the pressure in the pressure chamber and the spring force on the drive valve core are less than the pressure applied to the inlet pressure chamber, the main opening / closing is fully opened. At this time, the first channel outputs flow, and the electronic expansion valve can achieve preset large flow output.

[0011] Preferably, the small flow rate proportional regulation has an arbitrary specific relationship between the flow rate change trend and the magnetic field change trend generated after the coil is energized.

[0012] Compared with the prior art, the beneficial effects of the present invention are:

[0013] (1) This invention is a pilot-operated electronic expansion valve structure, which effectively solves the problem of small output flow rate; at the same time, it solves the problem that the force or torque generated by the coil and internal structure cannot overcome the internal medium pressure when the flow rate output is increased; it effectively meets the refrigeration system with a wide range of flow rate requirements; it effectively solves the problem of weak resistance to foreign objects in existing large flow rate expansion valves; the invention has a simple structure, low cost, and is convenient for people to use.

[0014] (2) The present invention is a pilot-operated electronic expansion valve structure that can simultaneously meet the needs of small flow output under certain working conditions and large flow output under certain working conditions, thereby reducing the operating cost of the thermal management system and saving the installation space of the thermal management system. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0016] Figure 2 This is a schematic cross-sectional view of the overall structure of the present invention;

[0017] Figure 3 for Figure 1 Partial structural diagram;

[0018] Figure 4 for Figure 3 A partial structural diagram.

[0019] In the attached diagram, the following are the reference numerals: 1. Fixed valve seat; 2. Valve sleeve; 3. Drive valve core; 4. Spring; 5. Push rod; 6. Pressure outlet chamber; 7. Pressure inlet chamber; 8. Pressure chamber; 9. Pressure relief channel; 10. Main opening and closing; 11. Auxiliary opening and closing; 12. Pressure supply channel; 13. Coil; 14. Sleeve; 15. Armature; 16. Guide thread; 17. Guide sleeve; 18. Thread pair; 19. First channel; 20. Second channel; 21. Sealing gasket; 22. Sealing ring. Detailed Implementation

[0020] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0021] Example

[0022] Please see Figure 1-4This invention proposes a pilot-operated electronic expansion valve structure: A pilot-operated electronic expansion valve structure includes a hydraulic component and an electrical component. The hydraulic component includes a fixed valve seat 1, with a valve sleeve 2 fixedly installed inside the fixed valve seat 1. The inner cavity of the valve sleeve 2 is provided with a drive valve core 3, a spring 4, and a push rod 5. Specifically, the push rod 5 is controlled by the electrical component to achieve axial reciprocating motion. The two ends of the spring 4 are respectively connected to the drive valve core 3 and the valve sleeve 2. Specifically, the drive valve core 3 can reciprocate under the action of spring force and pressure. The push rod 5 is connected to the electrical component. A pressure outlet chamber 6 is provided on the fixed valve seat 1, and a pressure inlet chamber is provided between one end of the fixed valve seat 1 and the drive valve core 3. 7. A pressure chamber 8 is provided between the push rod 5 and the drive valve core 3. A pressure relief channel 9 is provided on the right side of the valve sleeve 2. A main switch 10 is provided between the outlet pressure chamber 6 and the inlet pressure chamber 7. A secondary switch 11 is provided between the pressure chamber 8 and the pressure relief channel 9. A pressure supply channel 12 is provided on the drive valve core 3. Specifically, the main switch 10 and the drive valve core 3 cooperate to separate the inlet pressure chamber 7 and the outlet pressure chamber 6. When the push rod 5 moves, the push rod 5 contacts the secondary switch 11, and the pressure chamber 8 and the pressure relief channel 9 are cut off. At this time, the internal pressure of the inlet pressure chamber 7 is considered as P1, the pressure of the pressure chamber 8 is considered as P2, and the pressure of the outlet pressure chamber 6 is considered as P3. Since the pressure chamber 8 and the inlet pressure chamber 7 are always connected through the pressurization channel, P1=P2 at this time. Since the pressure outlet chamber 6 is connected to the outside of the valve body, P3 < P1. Under the action of spring force and pressure, the drive valve core 3 is pressed against the end face of the main opening and closing mechanism 10. At this time, the pressure inlet chamber 7 and the pressure outlet chamber 6 are closed. When the push rod 5 moves, the pressure chamber 8 is connected to the pressure relief channel 9. The pressure in the pressure chamber 8 is P2 < P1. The left force-bearing surface of the drive valve core 3 bears pressure. This pressure overcomes the spring force, and the drive valve core 3 moves to the right away from the main opening and closing mechanism 10. At this time, the pressure inlet chamber 7 and the pressure outlet chamber 6 are connected. Through the movement of the drive valve core 3, the contact surface between the drive valve core 3 and the fixed valve seat 1 is brought closer and separated, realizing the opening and closing of the main opening and closing mechanism 10, which can open and close the channel between the pressure inlet chamber 7 and the pressure outlet chamber 6. Driven by the electrical assembly, the push rod 5 can reciprocate axially, enabling the contact surfaces between the push rod 5 and the valve sleeve 2 to approach and separate, thus opening and closing the secondary opening and closing between the pressure chamber 8 and the pressure relief channel 9. The electrical assembly includes a coil 13, inside which is a sleeve 14, and inside which is an armature 15, which is fixedly connected to a guide thread 16. Inside the valve sleeve 2, a guide sleeve 17 is also installed, and a threaded pair 18 is provided between the guide sleeve 17 and the guide thread 16. Specifically, the electrical assembly controls the opening and closing functions of the push rod 5 and the secondary opening and closing 11 to realize the opening and closing functions of the pressure chamber 8 and the pressure relief channel 9, thereby indirectly controlling the opening and closing functions of the inlet pressure chamber 7 and the outlet pressure chamber 6.

[0023] Specifically: After the armature 15 is connected to the push rod 5, it reciprocates along the axial direction together with the armature 15, including but not limited to the following methods to achieve the reciprocating motion of the push rod along the axial direction:

[0024] (1) The coil 13 applies a magnetic force to the armature 15, and through the pressure transmitted by the push rod 5 via the internal spring or the hydraulic assembly, the armature 15 moves back and forth in a straight line along the axis.

[0025] (2) The coil 13 applies a magnetic force to the armature 15, causing the armature 15 to rotate along the axial direction. The rotational movement of the armature 15 is converted into linear motion along the axial direction by adding an internal threaded guide mechanism. (The hydraulic components and the threaded guide mechanism adopt existing technology).

[0026] Please see Figure 1-4 As shown, the fixed valve seat 1 is further provided with an oil passage connecting to the external environment. The oil passage includes a first passage 19 and a second passage 20. The pressure outlet chamber 6 and the pressure relief passage 9 can be connected to the external environment through the first passage 19 or the second passage 20.

[0027] In this embodiment, the medium pressure generated inside the second channel 20 and the first channel 19 is proportional to their flow output capacity. That is, the greater the required flow output, the greater the medium pressure generated inside the second channel 20 and the first channel 19. If the first channel 19 is directly driven by the electrical components, the force or torque generated by the coil 13 and its internal structure under limited conditions cannot overcome the medium pressure generated by the first channel 19. Therefore, by adjusting the opening degree of the auxiliary opening and closing 11, the pressure in the pressure chamber 8 is controlled. Combined with the spring force and pressure on the driving valve core 3, the opening and closing of the first channel 19 is indirectly adjusted. The flow output capacity of the second channel 20 should be less than the flow output capacity of the first channel.

[0028] Please see Figure 1-4 As shown, when the auxiliary switch 11 is closed, the medium pressure in the pressure inlet chamber 7 can be transmitted to the interior of the pressure chamber 8, and the pressure in the pressure inlet chamber 7 and the pressure in the pressure chamber 8 are equal; when the auxiliary switch 11 is opened, the medium pressure in the pressure inlet chamber 7 and the medium pressure in the pressure chamber 8 are released through the pressure relief channel 9, and the pressure in the pressure chamber 8 is reduced.

[0029] Please see Figure 2-3 As shown, further, the opening (A) and closing (A0) functions of the auxiliary switch 11, the pressure reduction (B) and increase (B0) inside the pressure chamber 8, and finally the opening (C) and closing (C0) functions of the main switch 10.

[0030] In this embodiment, the control logic relationship between the auxiliary switch 11, the pressure chamber 8, and the main switch 10 is not limited to any relationship such as ABC, A0-B0-C0, A-B0-C, A0-B-C0, AB-C0, A0-B0-C, A-B0-C0, or A0-BC.

[0031] In this embodiment, the first channel 10 and the second channel 20 may converge and connect inside the valve body before connecting to the external environment, or they may converge outside the valve body before connecting to the external environment, or they may each have their own independent channel connecting to the external environment.

[0032] Furthermore, the opening and closing position of the second channel 20 is located at the auxiliary switch 11. The armature 15 inside the electrical component is affected by the magnetic field after the coil 13 is energized, which drives the push rod 5 to move axially continuously. By changing the magnetic field after energization, the push rod 5 can be kept at any position within the preset stroke. The distance between the push rod 5 and the auxiliary switch 11 is called the opening degree of the auxiliary switch 11. The flow rate of the medium flowing from the hydraulic component to the external environment through the second channel 20 is directly controlled by the opening degree of the auxiliary switch 11. By adjusting the magnetic field generated by the coil 13, the opening degree of the auxiliary switch 11 within the preset range is adjusted so that the flow rate through the second channel 20 can be kept at any size within the preset range. This adjustment process is called small flow rate proportional adjustment.

[0033] Furthermore, the opening and closing position of the first channel 19 of the electronic expansion valve is located at the main opening and closing position 10. The pressure inside the pressure chamber 8 is adjusted by the opening degree of the auxiliary opening and closing position 11. The pressure and spring force at both ends of the drive valve core 3 change, causing the drive valve core 3 to move away from or close to the main opening and closing position 10, thereby realizing the opening and closing of the main opening and closing position 10. By preset the spring force and pressure on the drive valve core 3, the opening degree of the auxiliary opening and closing position 11 exists at a certain key position. Between the preset initial position and the key position, the pressure applied to the drive valve core 3 in the pressure chamber 8 plus the spring force is greater than the pressure on the drive valve core 3 in the inlet pressure chamber 7. During this period, only the second channel 20 participates in the flow output, and the electronic expansion valve can realize preset small-range proportional flow adjustment. When the push rod 5 moves from the key position to the preset end position, the pressure and spring force on the drive valve core 3 in the pressure chamber 8 are less than the pressure applied by the inlet pressure chamber 7, the main opening and closing position 10 is fully opened. At this time, the first channel 19 outputs flow, and the electronic expansion valve can realize preset large flow output.

[0034] Preferably, the small flow rate proportional regulation has an arbitrary and specific relationship between the flow rate change trend and the magnetic field change trend generated after the coil 13 is energized.

[0035] In the description of this invention, it should be understood that the terms "coaxial," "bottom," "one end," "top," "middle," "other end," "upper," "side," "top," "inner," "front," "center," "both ends," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0036] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "setting," "connection," "fixing," "screw connection," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two components or the interaction between two components. Unless otherwise explicitly limited, those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0037] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A pilot-operated electronic expansion valve structure, characterized in that, The device includes a hydraulic assembly and an electrical assembly. The hydraulic assembly includes a fixed valve seat (1), and a valve sleeve (2) is fixedly installed inside the fixed valve seat (1). The inner cavity of the valve sleeve (2) is provided with a drive valve core (3), a spring (4), and a push rod (5). The two ends of the spring (4) are respectively connected to the drive valve core (3) and the valve sleeve (2). The push rod (5) is connected to the electrical assembly. The fixed valve seat (1) is provided with a pressure outlet chamber (6). A pressure inlet chamber (7) is provided between one end of the fixed valve seat (1) and the drive valve core (3). A pressure chamber (8) is provided between the push rod (5) and the drive valve core (3). The right side of the valve sleeve (2) is provided with... A pressure relief channel (9) is provided. A main switch (10) is provided between the pressure outlet chamber (6) and the pressure inlet chamber (7). A secondary switch (11) is provided between the pressure chamber (8) and the pressure relief channel (9). A pressure supply channel (12) is provided on the drive valve core (3). The electrical assembly includes a coil (13). A sleeve (14) is provided inside the coil (13). An armature (15) is provided inside the sleeve (14). The armature (15) is fixedly connected to a guide thread (16). A guide sleeve (17) is also installed inside the valve sleeve (2). A threaded pair is provided between the guide sleeve (17) and the guide thread (16). 18) The fixed valve seat (1) is provided with an oil passage connecting to the external environment. The oil passage includes a first passage (19) and a second passage (20). The pressure outlet chamber (6) and the pressure relief passage (9) can be connected to the external environment through the first passage (19) or the second passage (20). The opening and closing position of the second passage (20) is located at the auxiliary opening and closing (11). The auxiliary opening and closing (11) is located on the valve sleeve (2). The armature (15) inside the electrical component is affected by the magnetic field after the coil (13) is energized, which drives the push rod (5) to move axially continuously. By changing the magnetic field after energization, the push rod (5) can be kept in place. At any position within the preset stroke, the distance between the push rod (5) and the secondary opening (11) is called the opening degree of the secondary opening (11). The flow rate of the medium flowing to the external environment through the second channel (20) of the hydraulic component is directly controlled by the opening degree of the secondary opening (11). By adjusting the magnetic field generated by the adjusting coil (13), the opening degree of the secondary opening (11) within the preset range is adjusted so that the flow rate through the second channel (20) can be maintained at any size within the preset range. This adjustment process is called small flow rate proportional adjustment. A sealing gasket (21) is installed on the end face of the valve sleeve (2), and a sealing ring (22) is installed between the fixed valve seat (1) and the valve sleeve (2).

2. The pilot-operated electronic expansion valve structure according to claim 1, characterized in that, When the secondary opening and closing (11) is closed, the medium pressure in the pressure inlet chamber (7) can be transmitted to the interior of the pressure chamber (8), and the pressure in the pressure inlet chamber (7) and the pressure in the pressure chamber (8) are equal; when the secondary opening and closing (11) is open, the medium pressure in the pressure inlet chamber (7) and the medium pressure in the pressure chamber (8) are released through the pressure relief channel (9), and the pressure in the pressure chamber (8) is reduced.

3. The pilot-operated electronic expansion valve structure according to claim 1, characterized in that, The opening and closing functions of the auxiliary switch (11), the pressure decrease and increase inside the pressure chamber (8), and finally the opening and closing functions of the main switch (10).

4. The pilot-operated electronic expansion valve structure according to claim 1, characterized in that, The opening and closing position of the first channel (19) of the electronic expansion valve is located at the main opening and closing (10). The pressure inside the pressure chamber (8) is adjusted by the opening degree of the auxiliary opening and closing (11). The pressure and spring force at both ends of the drive valve core (3) change, causing the drive valve core (3) to move away from or close to the main opening and closing (10) position, thereby realizing the opening and closing of the main opening and closing (10). By preset the spring force and pressure on the drive valve core (3), the opening degree of the auxiliary opening and closing (11) exists at a certain key position. Between the preset initial position and the key position of the push rod (5), the pressure chamber (8) When the pressure applied to the drive valve core (3) plus the spring force is greater than the pressure of the inlet chamber (7) on the drive valve core (3), during this period, only the second channel (20) participates in the flow output, and the electronic expansion valve can realize the preset small range flow ratio adjustment; when the push rod (5) is between the key position and the preset end position, when the pressure of the pressure chamber (8) on the drive valve core (3) and the spring force are less than the pressure applied by the inlet chamber (7), the main opening and closing (10) is fully opened, and at this time the first channel (19) outputs flow, and the electronic expansion valve can realize the preset large flow output.

5. The pilot-operated electronic expansion valve structure according to claim 1, characterized in that, The small flow rate proportional regulation has an arbitrary and specific relationship between the flow rate change trend and the magnetic field change trend generated after the coil (13) is energized.

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