High-precision flow regulating proportional valve

Abstract

The application relates to a high-precision flow regulating proportional valve, and belongs to the technical field of proportional valves, which comprises a valve seat provided with a hole groove structure in the axial direction; a connecting rod provided with an oil inlet channel, one end of the connecting rod being provided with a conical surface; a valve sleeve slidably arranged in the hole groove structure and coaxially arranged outside the connecting rod, one end of the valve sleeve being closed, the other end being an open end, and the inner edge of the open end of the valve sleeve being matched with the conical surface to form a valve port; a top pin slidably arranged on the connecting rod, one end of the top pin being used for bearing the oil pressure from the oil inlet channel, the other end being used for pushing the valve sleeve to move when bearing the oil pressure; and an elastic member used for applying a pre-tightening force to the valve sleeve towards the conical surface. The application reduces the machining difficulty of parts, is beneficial to improving product consistency, and is convenient for realizing large-scale mass production. Meanwhile, the addition of an electromagnetic driving mechanism is beneficial to realizing electric control regulation, so that flow control is more flexible and response is more rapid.

Description

Technical Field

[0001] This application relates to the field of proportional valves, and more particularly to a high-precision flow regulating proportional valve. Background Technology

[0002] Proportional valves, as key control components in hydraulic systems, can continuously and proportionally adjust fluid flow based on input electrical signals and are widely used in fields such as engineering machinery and automotive vibration damping. Chinese Patent Publication No. CN121828387A discloses a CDC proportional valve for motor vehicles. This proportional valve mainly includes a housing, a valve sleeve assembly, and a valve stem assembly. The valve sleeve assembly consists of a first valve seat and a second valve seat. A conical surface is provided between the second valve seat and the valve stem. By reciprocating the valve stem, the size of the opening gap between the second valve seat and the conical surface is changed, thereby achieving continuous flow regulation. In this structure, the displacement of the valve stem directly determines the flow area of ​​the annular throttling orifice, thus controlling the output flow rate.

[0003] However, in the above technical solution, the flow area of ​​the annular throttling orifice is proportional to the valve stem displacement and the sine of the cone's half-cone angle. To achieve precise flow regulation and avoid drastic flow changes caused by minute valve stem displacement, the taper of the cone must be controlled within an extremely small range during the design process to ensure that the area change rate corresponding to a unit displacement is sufficiently low, thereby obtaining sufficient regulation resolution.

[0004] Regarding the above technical solution, the inventor believes that the proportional valve relies excessively on the precise geometric dimensions of the conical surface to achieve flow regulation. The taper of the conical surface must be extremely small and the machining accuracy requirement is extremely high, resulting in poor product consistency and difficulty in mass production. Summary of the Invention

[0005] In order to reduce the dependence on the machining accuracy of parts and improve product consistency and mass production feasibility, this application provides a high-precision flow regulating proportional valve.

[0006] This application provides a high-precision flow regulating proportional valve, which adopts the following technical solution: A high-precision flow regulating proportional valve, comprising: The valve seat has a slotted structure along its axial direction; The connecting rod is provided with an oil inlet channel, and one end of the connecting rod has a tapered surface on its outer edge. A valve sleeve is slidably disposed within the slot structure and coaxially disposed outside the connecting rod. One end of the valve sleeve is closed and the other end is open. The inner edge of the open end of the valve sleeve mates with a conical surface to form a valve port. A push pin is slidably mounted on the connecting rod. One end of the push pin is used to withstand the oil pressure from the oil inlet channel, and the other end is disposed opposite to the inner side of the closed end of the valve sleeve, so as to push the valve sleeve to move when subjected to oil pressure. An elastic element is provided between the valve seat and the valve sleeve, for applying a preload force toward the conical surface to the valve sleeve; An electromagnetic drive mechanism is located on the side of the valve seat away from the connecting rod, and is used to drive the valve sleeve to move axially.

[0007] Optionally, the slot structure includes a through hole, a receiving slot, a stepped slot, an oil outlet cavity, and a plug hole arranged sequentially along the axial direction. The stepped slot is used to accommodate the valve sleeve and allow it to slide axially. The plug hole is used to plug in the connecting rod. The valve seat is also provided with a first oil hole communicating with the oil outlet cavity.

[0008] Optionally, the connecting rod has a neck at one end near the conical surface, and the outer peripheral surface of the neck has a second oil hole communicating with the oil inlet channel.

[0009] Optionally, the end of the constricted neck away from the conical surface is provided with an inner guide block, the open end of the valve sleeve is slidably fitted onto the outer periphery of the inner guide block, the inner guide block is provided with a guide hole along the axial direction, one end of the ejector pin is slidably inserted into the guide hole, the guide hole is connected to the oil inlet channel so that the oil pressure acts on the end face of the ejector pin.

[0010] Optionally, one end of the ejector pin is a small head and the other end is a large head. The small head slides through the guide hole, and the large head is located inside the valve sleeve and is positioned opposite to the inner side of the closed end of the valve sleeve.

[0011] Optionally, a balance cavity is formed between the inner guide block and the closed end of the valve sleeve, and a balance hole communicating with the balance cavity is provided on the valve sleeve; a sliding gap is formed between the valve sleeve and the stepped groove, and the balance hole communicates with the oil outlet cavity through the sliding gap.

[0012] Optionally, the closed end of the valve sleeve is provided with a push rod, which passes through the through hole axially and is connected to the electromagnetic drive mechanism.

[0013] Optionally, it also includes a housing, the valve seat being fixed to the housing, and the electromagnetic drive mechanism including a magnetic core disposed inside the housing and a coil surrounding the outside of the magnetic core, one end of the magnetic core being connected to a push rod.

[0014] Optionally, the elastic element is a helical compression spring sleeved on the outside of the ejector pin, with one end abutting against the bottom wall of the receiving groove and the other end abutting against the closed end of the valve sleeve.

[0015] In summary, this application includes at least one of the following beneficial technical effects: 1. Through the design of the ejector pin and elastic element, the ejector pin converts the oil pressure into axial thrust, forming a dynamic balance with the preload of the elastic element. The position of the valve sleeve is automatically determined by this balance point, rather than being precisely controlled by mechanical displacement. Although the valve orifice formed by the conical surface and the inner edge of the valve sleeve opening is a throttling part, its opening degree is determined by the force balance result, not solely by the geometry of the conical surface. Therefore, even if the taper of the conical surface is large or there are certain manufacturing errors, as long as the force balance system can operate stably, the valve orifice opening can still be continuously and accurately adjusted with changes in oil pressure. This means that the conical surface does not need to be machined to an extremely small taper, nor does it need to achieve extremely high dimensional accuracy, reducing the machining difficulty and manufacturing cost of parts, which is conducive to improving product consistency and facilitating mass production. At the same time, the addition of the electromagnetic drive mechanism can superimpose an additional initial resistance value on the force balance, thereby realizing electronic control regulation, making flow control more flexible and responsive.

[0016] 2. Through the design of the inner guide block and guide hole, the inner guide block provides radial support and precise axial sliding guidance for the open end of the valve sleeve, ensuring that the valve sleeve maintains coaxiality with the connecting rod during movement and preventing leakage or wear at the valve port due to eccentricity. The guide hole guides the ejector pin along the axial direction and introduces oil from the oil inlet channel into the ejector pin end face, allowing the oil pressure to act directly and effectively on the ejector pin, ensuring sensitive force transmission.

[0017] 3. By designing the two ends of the ejector pin with a smaller diameter, the smaller head has a smaller diameter and low friction when sliding in the guide hole, while the larger head has a larger diameter and plays a mechanical limiting role. Even if there is no oil pressure or the pressure is low in the oil inlet channel, the ejector pin will not come out of the guide hole, thus ensuring the reliability and safety of the structure.

[0018] 4. Through the design of the balance chamber, balance hole, and sliding clearance, the pressure in the balance chamber is always consistent with that in the oil outlet chamber, thereby canceling out the axial pressures on both sides of the valve sleeve and eliminating the additional axial force caused by the pressure difference. This ensures that the axial position of the valve sleeve is determined only by the push force of the ejector pin, the preload of the elastic element, and the electromagnetic force, improving the linearity of adjustment and anti-interference capability. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of a high-precision flow regulating proportional valve according to an embodiment of this application.

[0020] Figure 2 This is a cross-sectional view illustrating the valve seat, valve sleeve, and connecting rod in the embodiments of this application.

[0021] Figure 3 This is a flow-pressure curve diagram illustrating the proportional valve in the embodiments of this application.

[0022] Explanation of reference numerals in the attached drawings: 1. Housing; 2. Valve seat; 21. Perforation; 22. Receiving groove; 23. Step groove; 231. Sliding clearance; 24. Oil outlet chamber; 25. Insertion hole; 26. First oil hole; 3. Connecting rod; 31. Oil inlet channel; 32. Conical surface; 33. Neck; 331. Second oil hole; 34. Inner guide block; 341. Guide hole; 4. Valve sleeve; 41. Push rod; 42. Balance chamber; 43. Balance hole; 5. Push pin; 51. Small head; 52. Large head; 6. Elastic element; 7. Electromagnetic drive mechanism; 71. Magnetic core; 72. Coil; 73. Guide sleeve. Detailed Implementation

[0023] The following combination Figures 1-3 This application will be described in further detail below.

[0024] Example: This application discloses a high-precision flow regulating proportional valve. (Refer to...) Figure 1 and Figure 2 A high-precision flow regulating proportional valve includes a housing 1 and a valve seat 2 fixed to one end of the housing 1. The valve seat 2 has a slotted structure along its axial direction, which includes a through hole 21, a receiving groove 22, a stepped groove 23, an oil outlet chamber 24, and a plug-in hole 25 sequentially formed along the axial direction. The radial dimensions of the through hole 21, the receiving groove 22, the stepped groove 23, and the oil outlet chamber 24 gradually widen. The diameter of the plug-in hole 25 is smaller than the radial dimension of the oil outlet chamber 24. A connecting rod 3 is inserted and fixed into the plug-in hole 25. For ease of explanation, in the valve seat 2, the end with the through hole 21 is the left end, and the end with the plug-in hole 25 is the right end. The left-right direction of the other components is consistent with the left-right direction of the valve seat 2.

[0025] Reference Figure 2 The connecting rod 3 has an oil inlet channel 31 along its axial direction. The outer edge of the left end of the connecting rod 3 is formed with a conical surface 32. The end of the connecting rod 3 near the conical surface 32 is integrally formed with a neck 33. The left end of the neck 33 is integrally formed with an inner guide block 34.

[0026] Reference Figure 1 and Figure 2 A valve sleeve 4 is slidably disposed in the stepped groove 23. One end of the valve sleeve 4 is closed and the other end is open. The open end of the valve sleeve 4 is slidably fitted onto the outer periphery of the inner guide block 34, and the inner edge of the open end of the valve sleeve 4 cooperates with the conical surface 32 to form a valve port.

[0027] Reference Figure 2The inner guide block 34 has a guide hole 341 along the axial direction. A push pin 5 is slidably arranged in the guide hole 341. The guide hole 341 is connected to the oil inlet channel 31 so that the oil pressure acts on the right end face of the push pin 5. The left end of the push pin 5 is arranged opposite to the inner side of the closed end of the valve sleeve 4, and is used to push the valve sleeve 4 to the left when subjected to oil pressure.

[0028] Reference Figure 1 and Figure 2 An elastic element 6 is provided between the valve seat 2 and the valve sleeve 4. The elastic element 6 is used to apply a preload force toward the conical surface 32 to the valve sleeve 4. A push rod 41 is integrally formed on the left side of the closed end of the valve sleeve 4. The push rod 41 passes through the through hole 21 axially and is connected to an electromagnetic drive mechanism 7. The electromagnetic drive mechanism 7 is located on the side of the valve seat 2 away from the connecting rod 3 and is used to drive the valve sleeve 4 to move axially.

[0029] In operation, the ejector pin 5 converts the oil pressure into axial thrust, which forms a dynamic balance with the preload of the elastic element 6. The position of the valve sleeve 4 is automatically determined by this balance point, rather than being precisely controlled by mechanical displacement. Although the valve port formed by the conical surface 32 and the inner edge of the valve sleeve 4's opening is a throttling part, its opening degree is determined by the force balance result, not solely by the geometry of the conical surface 32. Therefore, even if the taper of the conical surface 32 is large or has certain manufacturing errors, as long as the force balance system can operate stably, the valve port opening degree can still be continuously and accurately adjusted according to changes in oil pressure. Furthermore, the addition of the electromagnetic drive mechanism 7 can superimpose an additional initial bias resistance value on top of the force balance, thereby achieving electronic control regulation.

[0030] Reference Figure 2 To facilitate the formation of a conductive path for the oil when the valve port is opened, a first oil hole 26 communicating with the oil outlet chamber 24 is provided on the outer periphery of the valve seat 2, and a second oil hole 331 communicating with the oil inlet channel 31 is provided on the outer periphery of the constricted neck 33. Thus, the oil in the oil inlet channel 31 acts on the end face of the ejector pin 5 through the guide hole 341, generating an axial thrust. This thrust pushes the ejector pin 5, which then pushes against the closed end of the valve sleeve 4, attempting to drive the valve sleeve 4 to move to the left. Simultaneously, the elastic element 6 applies a pre-tightening force to the right on the valve sleeve 4, creating a force balance opposite to the thrust of the ejector pin 5. When the oil pressure is low, the thrust of the ejector pin 5 is insufficient to overcome the pre-tightening force of the elastic element 6, and the valve port remains closed. As the oil pressure increases, the thrust of the ejector pin 5 gradually increases. When the thrust exceeds the pre-tightening force of the elastic element 6, the valve sleeve 4 begins to move to the left, and the valve port opens accordingly. The oil flows out through the first oil hole 26, the valve port, the oil outlet chamber 24, and then through the second oil hole 331.

[0031] Reference Figure 2The ejector pin 5 has a small head 51 at one end and a large head 52 at the other end. The small head 51 slides through the guide hole 341, while the large head 52 is located inside the valve sleeve 4 and is positioned opposite to the inner side of the closed end of the valve sleeve 4. By designing the ejector pin 5 with a small head 51, which has a smaller diameter and lower friction when sliding in the guide hole 341, and the large head 52, which has a larger diameter, it plays a mechanical limiting role. Even when there is no oil pressure or the pressure is low in the oil inlet channel 31, the ejector pin 5 will not come out of the guide hole 341, ensuring the reliability and safety of the structure.

[0032] Reference Figure 2 A balance chamber 42 is formed between the inner guide block 34 and the closed end of the valve sleeve 4. A balance hole 43 is provided on the outer periphery of the valve sleeve 4 to connect with the balance chamber 42. A sliding gap 231 is formed between the valve sleeve 4 and the stepped groove 23. The balance hole 43 is connected to the oil outlet chamber 24 through the sliding gap 231. Through the sequential connection of the balance chamber 42, the balance hole 43, the sliding gap 231 and the oil outlet chamber 24, the pressure in the balance chamber 42 is always consistent with that in the oil outlet chamber 24, thereby canceling out the axial pressure on the inner and outer sides of the valve sleeve 4 and eliminating the additional axial force caused by the pressure difference. This ensures that the axial position of the valve sleeve 4 is determined only by the thrust of the ejector pin 5, the preload of the elastic element 6 and the electromagnetic force, improving the linearity of adjustment and anti-interference ability.

[0033] Reference Figure 1 and Figure 2 The elastic element 6 is a helical compression spring sleeved outside the ejector pin 5. One end of the helical compression spring abuts against the bottom wall of the receiving groove 22, and the other end abuts against the closed end of the valve sleeve 4. Thus, the preload formula for the elastic element 6 follows Hooke's Law, and the expression is: Among them, F 弹 In the initial installation state, the elastic element 6 has a certain pre-compression amount x0, and the resulting preload is: When the valve sleeve 4 is displaced by Δx under the action of external force, the total compression of the elastic element 6 becomes x0+Δx (or x0-Δx, depending on the direction of displacement), and the corresponding preload also changes linearly.

[0034] In this application, the preload of the elastic element 6 and the thrust of the ejector pin 5 constitute a force balance system. When the valve sleeve 4 is in a steady-state position, the following balance relationship is satisfied: Where P is the oil pressure, S is the effective pressure-bearing area of ​​the ejector pin 5, and in this embodiment, S is the cross-sectional area of ​​the end face of the small head 51, and Δx is the displacement of the valve sleeve 4 relative to the initial position.

[0035] Reference Figure 1 and Figure 2The electromagnetic drive mechanism 7 includes a magnetic core 71 disposed within the housing 1 and a coil 72 surrounding the outside of the magnetic core 71. One end of the magnetic core 71 is connected to the push rod 41. To ensure the stability of the axial movement of the magnetic core 71, a guide sleeve 73 is fixed inside the housing 1 to guide the movement of the magnetic core 71. The guide sleeve 73 is located between the magnetic core 71 and the coil 72.

[0036] Reference Figure 3 , Figure 3 This is a flow-pressure characteristic curve of an embodiment of this application. When the coil 72 is not energized, that is, when the test current of the coil 72 is zero, the displacement of the valve sleeve 4 is determined by the force balance point between the thrust of the ejector pin 5 and the preload of the elastic element 6. The thrust of the ejector pin 5 is equal to the axial pressure on the small head 51. The greater the axial pressure, the greater the valve flow rate. When the coil 72 is energized, the greater the test current of the coil 72, the stronger the electromagnetic force, and the higher the axial pressure threshold of the ejector pin 5 required for the valve sleeve 4 to move to the left. Under the same axial pressure condition, the greater the test current, the smaller the valve opening and the smaller the flow rate.

[0037] The implementation principle of a high-precision flow regulating proportional valve according to an embodiment of this application is as follows: When the coil 72 is not energized, the oil in the oil inlet channel 31 acts on the end face of the ejector pin 5 through the guide hole 341, generating an axial thrust. This thrust pushes the ejector pin 5, causing its large head 52 to push against the closed end of the valve sleeve 4, attempting to drive the valve sleeve 4 to move to the left. At the same time, the elastic element 6 applies a pre-tightening force to the right to the valve sleeve 4, forming a force balance in the opposite direction to the thrust of the ejector pin 5. When the oil pressure is low, the thrust of the ejector pin 5 is insufficient to overcome the pre-tightening force of the elastic element 6, and the valve port is in a closed state; as the oil pressure increases, the thrust of the ejector pin 5 gradually increases. When the thrust exceeds the pre-tightening force of the elastic element 6, the valve sleeve 4 begins to move to the left, and the valve port opens accordingly. The oil flows out from the second oil hole 331 after passing through the first oil hole 26, the valve port, and the oil outlet chamber 24. The displacement of valve sleeve 4 is automatically determined by the balance point between the thrust of ejector pin 5 and the preload of elastic element 6. The thrust of ejector pin 5 is determined by oil pressure. The higher the oil pressure, the greater the leftward movement of valve sleeve 4, the greater the valve opening, and the greater the flow rate.

[0038] When coil 72 is energized, electromagnetic drive mechanism 7 generates electromagnetic force, which applies an additional rightward thrust to valve sleeve 4 via push rod 41. This thrust is equivalent to adding an adjustable initial bias force to the preload of elastic element 6, requiring valve sleeve 4 to have a larger push force from push pin 5 to overcome the total resistance and move to the left. Therefore, the larger the energizing current, the stronger the electromagnetic force, and the higher the oil pressure threshold required for valve sleeve 4 to move to the left. Under the same oil pressure environment, the larger the current, the smaller the valve opening and the smaller the flow rate. By adjusting the current, the flow-pressure characteristic curve can be shifted and shaped, thereby achieving high-precision proportional regulation over a wide range.

[0039] In this proportional valve, the hydraulic pressure is converted into axial thrust by the ejector pin 5, which forms a dynamic force balance with the preload of the elastic element 6. The position of the valve sleeve 4 is automatically determined by the force balance point, rather than being precisely controlled by mechanical displacement. Although the valve orifice formed by the conical surface 32 and the inner edge of the valve sleeve 4 is a throttling part, its opening degree is determined by the force balance result, rather than solely by the geometry of the conical surface 32. Even if the taper of the conical surface 32 is large or there are certain manufacturing errors, as long as the force balance system can operate stably, the valve orifice opening can still be continuously and accurately adjusted according to changes in hydraulic pressure. Therefore, the conical surface 32 does not need to be machined to an extremely small taper, nor does it need to achieve extremely high manufacturing precision, reducing the dependence on the precision of parts machining, which is conducive to improving product consistency and facilitating mass production. At the same time, the addition of the electromagnetic drive mechanism 7 enables electronic control regulation, making flow control more flexible, response faster, and adaptable to diverse operating conditions.

[0040] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A high-precision flow regulating proportional valve, characterized in that, include: Valve seat (2) has a slotted structure along its axial direction; The connecting rod (3) is provided with an oil inlet channel (31), and a tapered surface (32) is provided on the outer edge of one end of the connecting rod (3); The valve sleeve (4) is slidably disposed in the slot structure and coaxially disposed outside the connecting rod (3). One end of the valve sleeve (4) is closed and the other end is open. The inner edge of the open end of the valve sleeve (4) cooperates with the conical surface (32) to form a valve port. A push pin (5) is slidably mounted on the connecting rod (3). One end of the push pin (5) is used to bear the oil pressure from the oil inlet channel (31), and the other end is disposed opposite to the inner side of the closed end of the valve sleeve (4) to push the valve sleeve (4) to move when bearing oil pressure. An elastic element (6) is provided between the valve seat (2) and the valve sleeve (4) for applying a preload force toward the conical surface (32) to the valve sleeve (4); An electromagnetic drive mechanism (7) is located on the side of the valve seat (2) away from the connecting rod (3) and is used to drive the valve sleeve (4) to move axially. The slot structure includes a through hole (21), a receiving groove (22), a stepped groove (23), an oil outlet chamber (24), and a plug hole (25) arranged sequentially along the axial direction. The stepped groove (23) is used to accommodate the valve sleeve (4) and allow it to slide axially. The plug hole (25) is used to plug in the connecting rod (3). The valve seat (2) is also provided with a first oil hole (26) that communicates with the oil outlet chamber (24).

2. The high-precision flow regulating proportional valve according to claim 1, characterized in that: The connecting rod (3) has a neck (33) at one end near the conical surface (32), and the outer circumferential surface of the neck (33) has a second oil hole (331) that communicates with the oil inlet channel (31).

3. The high-precision flow regulating proportional valve according to claim 2, characterized in that: The neck (33) is provided with an inner guide block (34) at one end away from the conical surface (32). The open end of the valve sleeve (4) is slidably fitted onto the outer periphery of the inner guide block (34). The inner guide block (34) is provided with a guide hole (341) along the axial direction. One end of the ejector pin (5) is slidably inserted into the guide hole (341). The guide hole (341) is connected to the oil inlet channel (31) so that the oil pressure acts on the end face of the ejector pin (5).

4. A high-precision flow regulating proportional valve according to claim 3, characterized in that: One end of the ejector pin (5) is a small head (51) and the other end is a large head (52). The small head (51) slides through the guide hole (341) and the large head (52) is located inside the valve sleeve (4) and is positioned opposite to the inner side of the closed end of the valve sleeve (4).

5. A high-precision flow regulating proportional valve according to claim 4, characterized in that: A balance cavity (42) is formed between the inner guide block (34) and the closed end of the valve sleeve (4). The valve sleeve (4) is provided with a balance hole (43) that communicates with the balance cavity (42). A sliding gap (231) is formed between the valve sleeve (4) and the stepped groove (23). The balance hole (43) communicates with the oil outlet cavity (24) through the sliding gap (231).

6. A high-precision flow regulating proportional valve according to claim 1, characterized in that: The valve sleeve (4) has a push rod (41) at its closed end. The push rod (41) passes through the through hole (21) axially and is connected to the electromagnetic drive mechanism (7).

7. A high-precision flow regulating proportional valve according to claim 6, characterized in that: It also includes a housing (1), the valve seat (2) is fixed on the housing (1), and the electromagnetic drive mechanism (7) includes a magnetic core (71) disposed in the housing (1) and a coil (72) surrounding the outside of the magnetic core (71). One end of the magnetic core (71) is connected to the push rod (41).

8. A high-precision flow regulating proportional valve according to claim 1, characterized in that: The elastic element (6) is a helical compression spring and is sleeved on the outside of the ejector pin (5). One end of the spring abuts against the bottom wall of the receiving groove (22), and the other end abuts against the closed end of the valve sleeve (4).

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