A proportional flow control valve

Abstract

The present disclosure relates to a proportional flow control valve, comprising a valve body, a throttle valve assembly and a compensation valve assembly. The valve body is provided with a valve cavity, an inlet passage and an outlet passage, and the valve cavity has a first end and a second end at opposite ends. The throttle valve assembly includes a throttle valve spool located at the first end of the valve cavity, and the inlet passage is communicated with the valve cavity at the throttle valve spool through a first communication port. The throttle valve spool is controlled by a driving device and adjusts the opening degree of the first communication port when moving. The compensation valve assembly includes a compensation valve spool located at the second end of the valve cavity, and the outlet passage is communicated with the valve cavity at the compensation valve spool through a second communication port. One end of the compensation valve spool adjacent to the second end of the valve cavity forms a control cavity with the second end of the valve cavity, and the valve body is provided with a damping passage communicating the inlet passage and the control cavity. The compensation valve spool moves under the action of the pressure difference between the two sides to adjust the opening degree of the second communication port. Through the self-adaptive adjustment of the compensation valve spool, the outlet flow can be stabilized, the influence of load change on control accuracy can be reduced, and the stability of load operation can be improved.

Description

Technical Field

[0001] This disclosure relates to the field of hydraulic technology, and specifically to a proportional flow control valve. Background Technology

[0002] Traditional proportional flow control valves used in hydraulic machinery are bulky and space-consuming. Although computer-controlled, their complex structure makes them unsuitable for hydraulic transmission systems. Furthermore, the control components are relatively complex, making them difficult for operators to master. They also require high oil cleanliness, leading to frequent malfunctions, difficult maintenance, and high repair costs. Therefore, there is an urgent need for a compact, high-response proportional flow control valve to precisely control the flow rate and direction of fluid, meeting the control performance requirements of the control system. Utility Model Content

[0003] This disclosure provides a proportional flow control valve to address the problems existing in the prior art.

[0004] According to a first aspect of this disclosure, a proportional flow control valve is provided, comprising: The valve body is configured to have a valve cavity, and an oil inlet passage and an oil outlet passage respectively communicating with the valve cavity; the two opposite ends of the valve cavity are respectively referred to as the first end and the second end; A throttle valve assembly includes a throttle valve core located at the first end of the valve chamber, and the oil inlet passage is configured to communicate with a position in the valve chamber corresponding to the throttle valve core through a first connecting port; the throttle valve core is configured to be controlled by a drive device to adjust the opening degree of the first connecting port during movement. A compensating valve assembly includes a compensating valve core located at the second end of the valve cavity. The oil outlet passage is configured to communicate with a position in the valve cavity corresponding to the compensating valve core via a second connecting port. The end of the compensating valve core adjacent to the second end of the valve cavity is configured to form a control chamber with the second end of the valve cavity. A damping passage is provided on the valve body, connecting the oil inlet passage and the control chamber. The compensating valve core is configured to move under the pressure difference on both sides to adjust the opening degree of the second connecting port.

[0005] In one embodiment of this disclosure, the compensating valve core is configured to move toward the first end when the pressure in the control chamber is greater than the pressure on the other side of the compensating valve core, so as to reduce the opening degree of the second communication port.

[0006] In one embodiment of this disclosure, the drive device is configured as a proportional electromagnet located on the valve body, and the output end of the proportional electromagnet is configured to abut against the throttle valve core.

[0007] In one embodiment of this disclosure, the throttle valve core is configured to be pre-compressed within the valve cavity by a first spring; the first spring is configured to push the throttle valve core toward closing the first connection port when the proportional electromagnet is de-energized.

[0008] In one embodiment of this disclosure, the compensating valve core is configured to be pre-compressed within the valve cavity by a second spring; the compensating valve core is configured to move toward the first end against the elastic force of the second spring when the pressure in the control cavity is greater than the pressure on the other side of the compensating valve core.

[0009] In one embodiment of this disclosure, the throttle valve assembly includes a throttle valve sleeve mounted within the valve chamber, the throttle valve core being configured to be movably connected within the throttle valve sleeve.

[0010] In one embodiment of this disclosure, the compensation valve assembly includes a compensation valve sleeve installed within the valve cavity, the compensation valve core being configured to be movably connected within the compensation valve sleeve; a gasket is disposed within the valve cavity at a position between the throttle valve assembly and the compensation valve assembly; one end of the throttle valve sleeve is configured to abut against one side of the gasket, and one end of the compensation valve sleeve is configured to abut against the other side of the gasket.

[0011] In one embodiment of this disclosure, a one-way valve chamber is provided in the valve body, and the one-way valve chamber is configured to communicate with the position corresponding to the throttle valve core and the oil outlet passage in the valve chamber, respectively; a one-way valve is provided in the one-way valve chamber, and the one-way valve is configured to allow only the passage from the oil outlet passage to the valve chamber to be open.

[0012] In one embodiment of this disclosure, the valve body is provided with a third communication port connecting the valve cavity and the one-way valve cavity, and a valve hole is provided in the one-way valve cavity for cooperating with the one-way valve and communicating with the oil outlet passage. The one-way valve is configured to be pre-pressed on the valve hole under the action of a third elastic device.

[0013] In one embodiment of this disclosure, a transition cover is provided between the proportional electromagnet and the valve body, the transition cover being fixed to the valve body and connected to a guide sleeve on the valve body; the proportional electromagnet is configured to be installed on the transition cover by a threaded connection.

[0014] One beneficial effect of this disclosure is that the proportional flow control valve provided by this disclosure includes a valve body, a throttle valve assembly, and a compensation valve assembly. The valve body has a valve cavity, with its two opposite ends referred to as the first end and the second end, respectively. The throttle valve assembly and the compensation valve assembly are both installed in the valve cavity. The oil inlet passage is connected to the throttle valve core located at the first end of the throttle valve assembly through a first connecting port, and the oil outlet passage is connected to the compensation valve core located at the second end of the compensation valve assembly through a second connecting port. The throttle valve core is controlled by a drive device and adjusts the opening degree of the first connecting port during its movement. The compensation valve core moves under the action of the pressure difference on both sides to adjust the opening degree of the second connecting port. A control cavity is formed between the end of the compensation valve core adjacent to the second end and the second end of the valve cavity, and a damping channel connecting the control cavity and the oil inlet passage is provided on the valve body.

[0015] The proportional flow control valve of this disclosure controls the flow rate of hydraulic oil by adjusting the opening degree of the first and second connecting ports. When the oil pressure in the inlet passage increases, the hydraulic oil can be directly sent to the outlet passage through the control chamber via the damping passage to prevent damage to the regulating valve assembly caused by excessive instantaneous oil pressure. This disclosure uses a high-performance proportional electromagnet as the driving device, which can remotely and steplessly control the flow of the hydraulic system. It has the advantages of simple operation, small size, fast response, small flow change, strong anti-interference ability, and low production cost.

[0016] Other features and advantages of this disclosure will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0017] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments of the present disclosure and, together with their description, serve to explain the principles of the present disclosure.

[0018] Figure 1 This is a schematic diagram of the overall structure of the proportional flow control valve provided in this disclosure; Figure 2 This is a partial structural schematic diagram of the proportional flow control valve provided in this disclosure; Figure 3 yes Figure 1 Enlarged view of the throttle valve assembly area marked at point A in the middle; Figure 4 yes Figure 1 Enlarged view of the compensation valve assembly area marked at point B in the middle.

[0019] Figures 1 to 4 The one-to-one correspondence between the component names and the reference numerals in the figures is as follows: 10. Valve body; 11. Valve chamber; 12. Oil inlet passage; 121. Oil inlet; 13. Oil outlet passage; 131. Oil outlet; 14. Guide sleeve; 15. Transition cover; 101. First end; 102. Second end; 20. Throttling valve assembly; 21. Throttling valve core; 22. Throttling valve sleeve; 23. First connecting port; 24. First spring; 30. Compensating valve assembly; 31. Compensating valve core; 32. Compensating valve sleeve; 33. Second connecting port; 34. Second spring; 35. Control chamber; 41. Proportional electromagnet; 42. Push rod; 60. Washer; 61. Patterned washer; 70. Damping passage; 80. One-way valve chamber; 81. One-way valve core; 82. One-way valve sleeve; 83. Third connecting port; 84. Third spring; 85. Valve hole. Detailed Implementation

[0020] Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present disclosure.

[0021] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this disclosure or its application or use.

[0022] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0023] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0024] In this article, terms such as "up," "down," "front," "back," "left," and "right" are used only to indicate the relative positional relationship between related parts, rather than to define the absolute position of these related parts.

[0025] In this article, "first," "second," etc., are used only to distinguish one another, and not to indicate degree of importance, order, or prerequisite for each other.

[0026] In this document, terms such as “equal” and “same” are not strict mathematical and / or geometric limitations, but also include errors that are understandable to those skilled in the art and permissible in manufacturing or use.

[0027] This disclosure provides a proportional flow control valve including a valve body, a throttle valve assembly, and a compensation valve assembly. The valve body has a valve cavity, with its two opposite ends referred to as a first end and a second end. Both the throttle valve assembly and the compensation valve assembly are installed within the valve cavity. An oil inlet passage is connected to the throttle valve core located at the first end of the throttle valve assembly via a first connecting port, and an oil outlet passage is connected to the compensation valve core located at the second end of the compensation valve assembly via a second connecting port. The throttle valve core is controlled by a drive device and adjusts the opening degree of the first connecting port during its movement. The compensation valve core moves under the action of the pressure difference on both sides to adjust the opening degree of the second connecting port. A control cavity is formed between the end of the compensation valve core adjacent to the second end and the second end of the valve cavity, and a damping channel connecting the control cavity and the oil inlet passage is provided on the valve body.

[0028] The proportional flow control valve of this disclosure controls the flow rate of hydraulic oil by adjusting the opening degree of the first and second connecting ports. When the oil pressure in the inlet passage increases, the hydraulic oil can be directly sent to the outlet passage through the control chamber via the damping passage to prevent damage to the regulating valve assembly caused by excessive instantaneous oil pressure. This disclosure uses a high-performance proportional electromagnet as the driving device, which can remotely and steplessly control the flow of the hydraulic system. It has the advantages of simple operation, small size, fast response, small flow change, strong anti-interference ability, and low production cost.

[0029] The specific embodiments of this disclosure are described below with reference to the accompanying drawings.

[0030] refer to Figures 1 to 4 This disclosure provides a proportional flow control valve, including: a valve body 10, a throttle valve assembly 20, and a compensation valve assembly 30. The valve body 10 has a valve cavity 11 and an oil inlet passage 12 and an oil outlet passage 13 respectively communicating with the valve cavity 11.

[0031] Specifically, such as Figure 1 As shown, an oil inlet 121 and an oil outlet 131 are respectively provided on the bottom surface of the valve body 10. The oil inlet 121 is connected to the oil inlet passage 12, and the oil outlet 131 is connected to the oil outlet passage 13. Sealing rings are installed on the oil outlet 131 and the oil inlet 121 to prevent hydraulic oil leakage. The proportional flow control valve of this disclosure can adopt a plate-mounted structure. The bottom of the valve body 10 is a flat mounting surface. During installation, the oil inlet 121 is precisely aligned with the oil inlet passage 12, and the oil outlet 131 is precisely aligned with the oil outlet passage 13, achieving oil circuit connection without the need for additional oil pipes for connection. The advantages of this structure are compact installation, reduced use of oil pipes, and reduced leakage risk caused by oil pipe connections; it also facilitates the centralized arrangement of multiple hydraulic devices, effectively simplifying the overall structure, improving space utilization, and facilitating later maintenance and repair.

[0032] In the proportional flow control valve of this disclosure, the two opposite ends of the valve chamber 11 are respectively designated as the first end 101 and the second end 102. Taking the illustrated direction as an example, the upper end of the valve chamber 11 of the proportional flow control valve is the first end 101, and its lower end is the second end 102. The throttle valve assembly 20 and the compensating valve assembly 30 are arranged coaxially within the valve chamber 11 of the valve body 10. The throttle valve assembly 20 is located at the first end 101 of the valve chamber 11, and the compensating valve assembly 30 is located at the second end 102 of the valve chamber 11. The two are interconnected, allowing for smooth flow of hydraulic oil.

[0033] like Figure 1 and Figure 3 As shown, the throttle valve assembly 20 includes a throttle valve core 21 located at the first end 101 of the valve cavity 11. The oil inlet passage 12 is connected to the position of the throttle valve core 21 in the valve cavity 11 through the first connecting port 23. The throttle valve core 21 is controlled by a driving device, and adjusts the opening degree of the first connecting port 23 during movement. The throttle valve core 21 of this disclosure can be directly installed in the valve cavity 11 and can move relative to the valve cavity 11. In another embodiment of this disclosure, the throttle valve assembly 20 includes a throttle valve sleeve 22 installed in the first end 101 of the valve cavity 11. The throttle valve sleeve 22 is fixed to the inner wall of the valve cavity 11, and the throttle valve core 21 is movably connected in the throttle valve sleeve 22.

[0034] Specifically, when the drive device receives an electrical signal, it pushes the throttle valve core 21 to move up and down inside the throttle valve sleeve 22; the throttle valve sleeve 22 has an opening at a position corresponding to the first connecting port 23, and the size of the opening can be adjusted when the throttle valve core 21 moves, thereby adjusting the opening degree of the first connecting port 23 and controlling the flow rate of hydraulic oil entering the throttle valve core 21 assembly from the oil inlet passage 12.

[0035] The throttle valve sleeve 22 serves as the motion guide and sealing base component for the throttle valve core 21. It is fixed to the inner wall of the valve cavity 11 via an interference fit and a set screw. The throttle valve sleeve 22 has a cylindrical hollow structure with a precision-machined guide surface on its inner wall, and its outer wall is adapted to the inner wall of the valve cavity 11. The overall dimensions of the throttle valve sleeve 22 can simultaneously accommodate the installation space of the valve cavity 11 and the movement requirements of the throttle valve core 21. Installing the throttle valve sleeve 22 provides stable axial motion guidance for the throttle valve core 21, separates the oil passage area inside the valve cavity 11, prevents disorderly leakage of hydraulic oil between the valve cavity 11 and the throttle valve core 21, and forms an adjustable throttle orifice in cooperation with the throttle valve core 21.

[0036] The compensation valve assembly 30 includes a compensation valve core 31 located at the second end 102 within the valve cavity 11. The oil outlet passage 13 communicates with the position corresponding to the compensation valve core 31 within the valve cavity 11 via a second communication port 33. The compensation valve core 31 of this disclosure can be directly installed within the valve cavity 11 and is movable relative to the valve cavity 11. In another embodiment of this disclosure, the compensation valve assembly 30 located at the second end 102 within the valve cavity 11 includes a compensation valve sleeve 32, and the compensation valve core 31 is configured to be movably connected within the compensation valve sleeve 32. Figure 1 and Figure 4 As shown, the compensating valve sleeve 32 is located at the second end 102 within the valve cavity 11 and is fixedly connected to the inner wall of the valve cavity 11 by an interference fit or a snap ring. The compensating valve core 31 is located within the compensating valve sleeve 32 and can move within the compensating valve sleeve 32 without friction. Taking the illustrated direction as an example, a second communication port 33 is provided on the right side of the second end 102 of the valve cavity 11, corresponding to the position of the compensating valve core 31; the compensating valve sleeve 32 also has an opening at the position corresponding to the second communication port 33; the size of the opening on the compensating valve sleeve 32 is changed by the movement of the compensating valve core 31, thereby adjusting the opening degree of the second communication port 33.

[0037] In this design, a control chamber 35 is formed between the end of the compensating valve core 31 adjacent to the second end 102 of the valve chamber 11 and the second end 102 of the valve chamber 11; a damping passage 70 is provided on the valve body 10, connecting the oil inlet passage 12 and the control chamber 35; the compensating valve core 31 moves under the action of the pressure difference on both sides to adjust the opening degree of the second connecting port 33. Figure 3 As shown, when the compensating valve core 31 moves toward the first end 101, a chamber, namely the control chamber 35, can be formed between the bottom of the compensating valve core 31 near the second end 102 and the inner wall of the second end 102 of the valve cavity 11. The damping channel opened at the bottom of the second end 102 of the valve cavity 11 connects the oil inlet passage 12 and the control chamber 35. The diameter of the damping passage 70 is usually set to a smaller specification. This is because an excessively small diameter will cause the hydraulic oil to flow into the control chamber 35 too slowly, resulting in a delayed response of the compensating valve core 31 and an inability to respond to changes in the oil inlet pressure in a timely manner. An excessively large diameter will cause the hydraulic oil to rush into the control chamber 35 quickly, resulting in a sudden increase in pressure within the control chamber 35, causing the compensating valve core 31 to move too sensitively or even oscillate, making it impossible to stably regulate the flow rate. Therefore, the diameter of the damping passage 70 needs to be set to a size that allows the hydraulic oil to flow into the control chamber 35 at a stable rate, balancing the timeliness of the compensation response and the smoothness of the movement.

[0038] Combination Figures 1 to 4When hydraulic oil enters the inlet passage 12 through the inlet port 121, it flows smoothly along the inner wall of the passage under the drive of the system oil pressure. First, it precisely enters the internal chamber of the throttle valve core 21 through the preset first connecting port 23. At this time, the hydraulic oil is simultaneously subjected to the vertical downward force of its own gravity and the axial thrust generated by the oil pressure. The dual forces work together to propel the oil to permeate uniformly into the compensation valve core 31 along the internal flow channel of the throttle valve core 21. During this process, the oil forms a stable flow field in the valve core chamber, avoiding turbulence caused by local pressure changes. Subsequently, the hydraulic oil, after compensation and adjustment, flows smoothly into the outlet passage 13 through the second connecting port 33. After completing a stable pressure transition in the passage, it finally flows out continuously from the outlet port 131 and is precisely delivered to the hydraulic cylinder, providing a stable power source for the actuator.

[0039] In a specific embodiment of this disclosure, reference is made to Figure 4 When the pressure in the control chamber 35 is greater than the pressure on the other side of the compensating valve core 31, the compensating valve core 31 moves toward the first end 101 to reduce the opening degree of the second connecting port 33. Specifically, when the oil pressure at the oil inlet 121 is too high, in order to ensure the accuracy and smoothness of load control, some hydraulic oil will be forced into the damping channel due to the excessive oil pressure; after the hydraulic oil flows to the control chamber 35, it pushes the compensating valve core 31 toward the first end 101, while some hydraulic oil from the throttle valve core 21 pushes the compensating valve core 31 toward the second end 102; under the pressure difference between the oil pressures on both sides of the compensating valve core 31, the compensating valve core 31 moves toward the side with lower pressure, thereby adjusting the opening degree of the second connecting port 33. Therefore, when the oil pressure on one side of the control chamber 35 is greater than the pressure on the other side of the compensation valve core 31, the hydraulic oil entering the control chamber 35 from the damping passage 70 will push the compensation valve core 31 to move towards the first end 101, reducing the opening degree of the second connecting port 33, thereby reducing the flow rate of hydraulic oil in the oil outlet passage 13, ensuring the smooth operation of the load such as the hydraulic cylinder, and improving the safety and accuracy of operation.

[0040] In one embodiment of this disclosure, a gasket 60 is disposed within the valve cavity 11 at a position between the throttle valve assembly 20 and the compensating valve assembly 30. One end of the throttle valve sleeve 22 abuts against one side of the gasket 60, and one end of the compensating valve sleeve 32 abuts against the other side of the gasket 60. Specifically, as... Figure 1As shown, to ensure the coaxiality accuracy and axial installation clearance of the throttle valve assembly 20 and the compensating valve assembly 30, washers 60 are provided at the bottom of the throttle valve sleeve 22 and the top of the compensating valve sleeve 32. These washers 60 are adjustment shims and can be made of wear-resistant and rigid metal, capable of withstanding axial pressure during assembly installation and preventing wear and deformation during long-term use. Oil holes can be made at the coaxial positions of the washers 60 with the throttle valve core 21 and the compensating valve core 31. The diameter of the oil holes should match the diameter of the oil passages inside the throttle valve core 21 and the compensating valve core 31 to ensure smooth hydraulic oil flow and prevent increased oil flow resistance due to excessively narrow holes, or structural strength issues due to excessively wide holes. The gasket 60 can compensate for the axial dimension error of the throttle valve sleeve 22 and the compensation valve sleeve 32 during the processing, as well as the flatness error of the mounting surface of the inner wall of the valve cavity 11. At the same time, it can ensure the precise coaxial arrangement of the throttle valve assembly 20 and the compensation valve assembly 30 in the valve cavity 11, and prevent the valve core from sticking or the oil circuit from leaking due to the eccentricity of the components.

[0041] In one embodiment of this disclosure, the driving device is a proportional electromagnet 41 located on the valve body 10, and the output end of the proportional electromagnet 41 abuts against the throttle valve core 21. A transition cover 15 is provided between the proportional electromagnet 41 and the valve body 10, and the transition cover 15 is fixed to the valve body 10 and connected to the guide sleeve 14 on the valve body 10. Specifically, refer to... Figure 1 The housing of the proportional electromagnet 41 is bolted to the upper end face of the transition cover 15. The push rod 42 inside serves as the output end, passing through the guide hole in the center of the transition cover 15 and the guide sleeve 14 located at the first end 101 of the valve body 10, precisely abutting against the upper end face of the throttle valve core 21. A sealing ring can also be installed between the push rod 42 and the guide sleeve 14 to prevent hydraulic oil in the valve chamber 11 from leaking outwards along the push rod 42. The proportional electromagnet 41 can generate an electromagnetic thrust proportional to the current intensity of the input electrical signal. This thrust can act directly on the throttle valve core 21 through the push rod 42, driving it to move axially within the throttle valve sleeve 22, thereby achieving proportional adjustment of the opening degree of the first connecting port 23, making the flow rate of hydraulic oil entering the valve chamber 11 linearly correspond to the input electrical signal.

[0042] The transition cover 15 can be fixed to the upper end face of the valve body 10 with bolts. The positioning boss on the lower end face of the transition cover 15 can precisely mate with the mounting hole at the first end 101 of the valve body 10, ensuring the coaxiality of the transition cover 15 and the valve cavity 11. The guide sleeve 14 is inserted into the guide hole at the first end 101 of the valve body 10 by interference fit. The lower end face of the transition cover 15 and the upper end face of the guide sleeve 14 are tightly fitted, and the guide hole in the center of the transition cover 15 is coaxial with the inner hole of the guide sleeve 14, providing double guidance support for the push rod 42 of the proportional electromagnet 41, preventing the push rod 42 from deflecting during movement. An O-ring can also be provided between the transition cover 15 and the upper end face of the valve body 10, embedded in the sealing groove on the lower end face of the transition cover 15, to further enhance the sealing of the connection between the two and prevent hydraulic oil leakage.

[0043] Furthermore, the proportional electromagnet 41 can be installed on the transition cover 15 via a threaded connection. Specifically, compared to the screw connection commonly used in traditional proportional flow control valves, the threaded connection not only simplifies the assembly process and allows for fine-tuning of installation accuracy by adjusting the tightening, but also improves the sealing performance of the connection through the tight engagement of the threaded surfaces, effectively preventing the intrusion of external impurities and internal oil leakage. Especially in operating conditions requiring high reliability or subject to frequent vibration, the threaded connection can resist vibration impact through the frictional force generated by the preload, significantly reducing the risk of loosening, and its structural stability is more significantly improved than that of the screw connection.

[0044] The proportional electromagnet 41 body is made of low-temperature resistant alloy material, while the matching sealing ring is made of low-temperature resistant fluororubber. This material maintains good elasticity and sealing performance within an extreme ambient temperature range of -45℃ to 50℃, preventing material hardening and cracking or seal failure due to excessively low temperatures. This material combination design not only ensures the electromagnetic conversion efficiency of the proportional electromagnet 41 in low-temperature environments but also effectively extends the service life of the valve body 10 by blocking the contact between hydraulic oil and the external environment through a reliable sealing structure, enabling the product to meet the usage requirements of special scenarios such as polar operations and low-temperature storage.

[0045] In one embodiment of this disclosure, the throttle valve core 21 is pre-compressed within the valve cavity 11 by a first spring 24; the first spring 24 is configured to push the throttle valve core 21 toward closing the first connection port 23 when the proportional electromagnet 41 is de-energized. Specifically, as Figure 3As shown, the first spring 24 can be a cylindrical helical compression spring, sleeved between the lower end face of the throttle valve core 21 and the inner wall of the throttle valve sleeve 22; the lower end of the first spring 24 abuts against the inner wall of the throttle valve sleeve 22, and its upper end abuts against the throttle valve core 21. When the proportional electromagnet 41 is not energized, the first spring 24 is in a pre-compressed state, and its elastic force pushes the throttle valve core 21 upward, so that the lower end face of the throttle valve core 21 is completely fitted with the opening of the first connecting port 23 on the throttle valve sleeve 22, thereby closing the first connecting port 23 and cutting off the connection between the oil inlet passage 12 and the valve chamber 11. When the proportional electromagnet 41 is energized and generates thrust, this thrust overcomes the preload of the first spring 24 and pushes the throttle valve core 21 downward, gradually opening the first connection port 23. As the electrical signal strengthens, the thrust increases, the valve core moves downward more, the opening widens, and the oil flow increases accordingly. After the power is cut off, the electromagnetic thrust disappears, and the throttle valve core 21 resets under the return force of the first spring 24, closing the first connection port 23 again, thus realizing the automatic reset function of the proportional flow control valve and improving the safety of equipment use.

[0046] In one embodiment of this disclosure, the compensation valve core 31 is pre-pressed within the valve cavity 11 by a second spring 34; when the pressure in the control cavity 35 is greater than the pressure on the other side of the compensation valve core 31, the compensation valve core 31 moves towards the first end 101 against the elastic force of the second spring 34. Specifically, as Figure 4 As shown, the second spring 34 is also a cylindrical helical compression spring, sleeved between the middle of the compensating valve core 31 and the inner wall of the compensating valve sleeve 32; the upper end of the second spring 34 abuts against the inner wall of the compensating valve sleeve 32, and the lower end abuts against the compensating valve core 31. In the initial state, the second spring 34 is in a pre-compressed state, and its elastic force pushes the compensating valve core 31 to move towards the second end 102, so that the opening on the compensating valve sleeve 32 corresponding to the second connecting port 33 maintains a certain initial opening degree, ensuring that the basic oil flow can pass through. When the pressure in the control chamber 35 increases, pushing the compensating valve core 31 to move towards the first end 101, the compensating valve core 31 will further compress the second spring 34. At this time, the reverse elastic force generated by the second spring 34 balances the pressure in the control chamber 35 and the oil pressure on the other side of the compensating valve core 31, slowing down the movement speed of the compensating valve core 31 and avoiding excessive adjustment of the opening degree due to sudden pressure changes. When the pressure in the control chamber 35 decreases, the elastic force of the second spring 34 pushes the compensation valve core 31 downward to reset, gradually increasing the opening. Through the buffering effect of the elastic force of the second spring 34, the adjustment process of the compensation valve core 31 is made smoother, further improving the stability of flow control.

[0047] refer to Figures 1 to 4In one specific embodiment of this disclosure, an annular perforated pad 61 is embedded in the upper end of the compensating valve sleeve 32. This perforated pad 61 is made of high-strength, wear-resistant alloy material, and its core function is to provide a precise positioning support surface for the upper and lower sets of springs. Simultaneously, the through-channel in the middle ensures smooth flow of hydraulic oil, avoiding additional resistance to the oil flow within the valve body 10. The perforated pad 61 and the compensating valve sleeve 32 are embedded in an interference fit design, ensuring that the position remains fixed under high pressure and vibration conditions, effectively preventing spring force imbalance caused by component displacement.

[0048] For the elastic reset structure of the throttle valve assembly 20, the upper end of the first spring 24 is tightly abutted against the lower end face of the throttle valve core 21, while the lower end is stably supported on the upper end face of the perforated pad 61. The rigid support of the perforated pad 61 enables precise control of the spring preload. In the elastic adjustment structure of the compensating valve core 31, the upper end of the second spring 34 abuts against the lower end face of the perforated pad 61, and the lower end forms a reliable abutment with the lower end of the compensating valve core 31. The perforated pad 61 enables the coaxial arrangement of the two sets of springs, ensuring the guiding accuracy of the valve core during reciprocating motion. When hydraulic oil flows through the central channel of the perforated pad 61, the upper and lower end faces of the perforated pad 61 simultaneously provide stable supporting reaction forces for the springs, ensuring that the spring's extension and contraction deformation is always within the preset range, thereby guaranteeing the dynamic adjustment response performance of the throttle valve core 21 and the compensating valve core 31.

[0049] In one specific embodiment of this disclosure, when the proportional flow control valve is working, the external control system inputs an electrical signal corresponding to the target flow rate to the proportional electromagnet 41. The proportional electromagnet 41 generates a corresponding electromagnetic thrust according to the strength of the electrical signal, which pushes the throttle valve core 21 to overcome the elastic force of the first spring 24 and move downward in the throttle valve sleeve 22, adjusting the size of the opening corresponding to the first communication port 23 of the throttle valve sleeve 22, and controlling the initial flow rate of hydraulic oil entering the valve chamber 11 in the oil inlet passage 12. Hydraulic oil flows into the compensation valve core 31 area through the internal oil passage of the throttle valve core 21. At the same time, some hydraulic oil slowly flows into the control chamber 35 through the damping passage 70 under the action of the inlet oil pressure, forming a pressure difference between the lower end (control chamber 35 side) and the upper end (throttle valve core 21 side) of the compensation valve core 31. Under the combined action of this pressure difference and the elastic force of the second spring 34, the compensation valve core 31 makes axial fine adjustment within the compensation valve sleeve 32. By changing the opening degree of the corresponding opening on the compensation valve sleeve 32 and the second connecting port 33, the oil flow is precisely adjusted twice to counteract the influence of inlet oil pressure fluctuations or load changes on the flow rate, so that the flow rate of the oil outlet passage 13 is stabilized at the value corresponding to the input electrical signal. When the inlet oil pressure suddenly increases, the pressure in the control chamber 35 also increases. The pressure at the upper end of the compensation valve core 31 is less than the pressure at the lower end, so the valve core moves upward, reducing the opening and decreasing the oil flow. When the inlet oil pressure decreases, the pressure in the control chamber 35 decreases, and the valve core moves downward under the action of the second spring 34 and the upper oil pressure, increasing the opening and increasing the oil flow. The flow is always kept constant, ensuring that the movement speed of the hydraulic cylinder and other loads is stable and controllable.

[0050] In one embodiment of this disclosure, a one-way valve chamber 80 is provided within the valve body 10. The one-way valve chamber 80 is connected to the position of the corresponding throttling valve core 21 within the valve chamber 11 and to the oil outlet passage 13. A one-way valve core 81 is movably connected within the one-way valve chamber 80, and the one-way valve core 81 only allows the passage from the oil outlet passage 13 to the valve chamber 11 to be open. A third communication port 83 is provided on the valve body 10, connecting the valve chamber 11 and the one-way valve chamber 80. A valve hole 85 is provided within the one-way valve chamber 80 for cooperating with the one-way valve core 81 and communicating with the oil outlet passage 13. The one-way valve is pre-pressed onto the valve hole 85 under the action of a third spring 84. (Reference) Figure 2The one-way valve sleeve 82 is fixedly connected to the one-way valve cavity 80 through a combination of interference fit and snap ring positioning. Specifically, the outer wall of the one-way valve sleeve 82 and the inner wall of the one-way valve cavity 80 are initially fixed using an interference fit. Simultaneously, an annular groove is formed in the middle of the one-way valve cavity 80 to install a third spring 84. The third spring 84 abuts against the lower end face of the one-way valve sleeve 82 to prevent the one-way valve sleeve 82 from moving upwards due to oil pressure during operation. The inner wall of the one-way valve sleeve 82 is machined with a precision guide groove to guide the axial movement of the one-way valve core 81, preventing the valve core from misaligning or jamming. The upper end of the one-way valve sleeve 82 has an oil hole corresponding to the third communication port 83, and the lower end has a sealing step adapted to the valve hole 85. The internal cavity provides sufficient space for the movement of the one-way valve core 81. Meanwhile, a sealing ring is provided between the inner wall of the one-way valve sleeve 82 and the one-way valve chamber 80, embedded in the sealing groove of the outer wall of the one-way valve sleeve 82, to prevent hydraulic oil leakage between the two and ensure the sealing performance and operational reliability of the one-way valve. Figure 2 As shown, the third connecting port 83 is located on the right side wall of the valve cavity 11, opposite to the first connecting port 23. The third connecting port 83 connects the area of ​​the throttle valve core 21 with the upper end of the one-way valve cavity 80. The valve hole 85 is located at the lower end of the one-way valve cavity 80 and connects to the oil outlet passage 13. A sealing cone surface is machined on the upper end face of the valve hole 85, which can be adapted to the cone surface structure at the lower end of the one-way valve core 81, and a seal is achieved through the cone surface fit. The third spring 84 is a cylindrical helical compression spring, which is sleeved between the upper end of the one-way valve core 81 and the top inner wall of the one-way valve sleeve 82. The upper end of the third spring 84 abuts against the top of the one-way valve sleeve 82, and the lower end abuts against the upper end face of the one-way valve core 81. In the initial state, the third spring 84 is in a pre-compressed state, and its elastic force pushes the one-way valve core 81 to move downward, so that the sealing cone surface at the lower end of the one-way valve core 81 is tightly fitted with the cone surface of the valve hole 85, sealing the valve hole 85. At this time, the one-way valve is in the closed state, preventing the hydraulic oil in the valve chamber 11 from flowing into the oil outlet passage 13 through the one-way valve chamber 80, ensuring that the oil flow can flow along the preset path during normal operation.

[0051] In one specific embodiment of this disclosure, when the hydraulic oil in the load needs to return quickly from the outlet 131, the hydraulic oil in the load flows upward through the outlet passage 13 to the valve hole 85. The pressure pushes the one-way valve core 81 upward, compressing the third spring 84, causing the sealing cone surface at the lower end of the one-way valve core 81 to separate from the cone surface of the valve hole 85, forming a return passage between them. The hydraulic oil enters the internal chamber of the one-way valve sleeve 82 through this return passage, then flows into the third connecting port 83 through the oil hole at the upper end of the one-way valve sleeve 82, and finally enters the area below the throttle valve sleeve 22 in the valve cavity 11. Subsequently, the hydraulic oil either enters the interior of the compensating valve core 31 through the oil hole of the gasket 60 between the throttle valve core 21 and the compensating valve core 31; or flows to the first connecting port 23 through the throttle valve core 21, and then returns to the hydraulic system oil tank from the inlet port 121 through the inlet passage 12, achieving rapid return of the load and meeting the requirements of rapid return of the hydraulic cylinder. When the return oil ends, the rebound force of the third spring 84 pushes the one-way valve core 81 downward to reset, and the sealing cone surface re-fits the valve hole 85, closing the one-way valve and preventing the hydraulic oil in the valve chamber 11 from flowing back into the oil outlet passage 13, thus ensuring the one-way nature of the oil circuit when the proportional flow control valve is working normally.

[0052] The various embodiments of this disclosure have been described above. These descriptions are exemplary and not exhaustive, and are not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or technical improvements to the embodiments in the market, or to enable others skilled in the art to understand the embodiments disclosed herein. The scope of this disclosure is defined by the appended claims.

Claims

1. A proportional flow control valve, characterized in that, include: The valve body (10) is configured to have a valve cavity (11) and an oil inlet passage (12) and an oil outlet passage (13) respectively communicating with the valve cavity (11); the two opposite ends of the valve cavity (11) are respectively referred to as the first end (101) and the second end (102). A throttle valve assembly (20) includes a throttle valve core (21) located at the first end (101) of the valve chamber (11). The oil inlet passage (12) is configured to communicate with the position in the valve chamber (11) corresponding to the throttle valve core (21) through a first connecting port (23). The throttle valve core (21) is configured to be controlled by a drive device to adjust the opening degree of the first connecting port (23) during movement. The compensation valve assembly (30) includes a compensation valve core (31) located at the second end (102) of the valve cavity (11). The oil outlet passage (13) is configured to communicate with the position of the compensation valve core (31) in the valve cavity (11) through a second connecting port (33). The end of the compensation valve core (31) adjacent to the second end (102) of the valve cavity (11) is configured to form a control cavity (35) with the second end (102) of the valve cavity (11). The valve body (10) is provided with a damping passage (70) connecting the oil inlet passage (12) and the control cavity (35). The compensation valve core (31) is configured to move under the action of the pressure difference on both sides to adjust the opening degree of the second connecting port (33).

2. The proportional flow control valve according to claim 1, characterized in that, The compensation valve core (31) is configured to move toward the first end (101) when the pressure in the control chamber (35) is greater than the pressure on the other side of the compensation valve core (31) in order to reduce the opening degree of the second communication port (33).

3. The proportional flow control valve according to claim 1, characterized in that, The drive device is configured as a proportional electromagnet (41) located on the valve body (10), and the output end of the proportional electromagnet (41) is configured to abut against the throttle valve core (21).

4. The proportional flow control valve according to claim 3, characterized in that, The throttle valve core (21) is configured to be pre-pressed in the valve chamber (11) by a first spring (24); the first spring (24) is configured to push the throttle valve core (21) to move in the direction of closing the first connection port (23) when the proportional electromagnet (41) is de-energized.

5. The proportional flow control valve according to claim 2, characterized in that, The compensation valve core (31) is configured to be pre-pressed in the valve chamber (11) by a second spring (34); the compensation valve core (31) is configured to move toward the first end (101) against the elastic force of the second spring (34) when the pressure in the control chamber (35) is greater than the pressure on the other side of the compensation valve core (31).

6. The proportional flow control valve according to claim 1, characterized in that, The throttle valve assembly (20) includes a throttle valve sleeve (22) installed in the valve chamber (11), and the throttle valve core (21) is configured to be movably connected within the throttle valve sleeve (22).

7. The proportional flow control valve according to claim 6, characterized in that, The compensation valve assembly (30) includes a compensation valve sleeve (32) installed in the valve chamber (11), and the compensation valve core (31) is configured to be movably connected in the compensation valve sleeve (32); a gasket (60) is provided in the valve chamber (11) at a position between the throttle valve assembly (20) and the compensation valve assembly (30); one end of the throttle valve sleeve (22) is configured to abut against one side of the gasket (60), and one end of the compensation valve sleeve (32) is configured to abut against the other side of the gasket (60).

8. The proportional flow control valve according to claim 1, characterized in that, The valve body (10) is provided with a one-way valve chamber (80), which is configured to communicate with the position of the throttle valve core (21) in the valve chamber (11) and the oil outlet passage (13), respectively; a one-way valve core (81) is provided in the one-way valve chamber (80), which is configured to allow only the passage from the oil outlet passage (13) to the valve chamber (11) to be open.

9. The proportional flow control valve according to claim 8, characterized in that, The valve body (10) is provided with a third communication port (83) connecting the valve cavity (11) and the one-way valve cavity (80). The one-way valve cavity (80) is provided with a valve hole (85) for cooperating with the one-way valve core (81) and communicating with the oil outlet passage (13). The one-way valve core (81) is configured to be pre-pressed on the valve hole (85) under the action of the third spring (84).

10. The proportional flow control valve according to claim 3, characterized in that, A transition cover (15) is provided between the proportional electromagnet (41) and the valve body (10). The transition cover (15) is fixed to the valve body (10) and connected to the guide sleeve (14) on the valve body (10). The proportional electromagnet (41) is configured to be installed on the transition cover (15) by means of a threaded connection.

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