Wet-type direct-drive rotary servo valve

Abstract

The utility model relates to the field of hydraulic components, in particular to a wet-type direct-drive rotary servo valve which comprises a valve body, a servo driving mechanism shell, a rotor valve element and a servo driving mechanism, a plurality of hydraulic oil ports are formed in the valve body, and a plurality of valve body cavities communicating with the hydraulic oil ports are formed in the valve body; the servo driving mechanism shell is arranged at one end of the valve body, a driving cavity is formed in the servo driving mechanism shell, the rotor valve element comprises a valve element part and a rotor part which are integrally formed, and the valve element part is rotationally arranged in the valve body so that the communication state between valve body cavities can be changed; the rotor part and the servo driving mechanism are correspondingly arranged in the driving cavity, the rotor part can be driven by the servo driving mechanism to rotate, the driving cavity communicates with the valve body cavity, and the driving efficiency and the control precision of the servo valve can be improved.

Description

Technical Field

[0001] This application relates to the field of hydraulic components, and particularly to a wet direct-drive rotary servo valve. Background Art

[0002] A hydraulic valve is a hydraulic component used to control the pressure, flow rate, and flow direction of a liquid in a hydraulic transmission. It can operate in manual, hydraulic control, or electric control modes and is an essential component in the field of hydraulic transmission. An electro-hydraulic servo valve, also known as a servo valve, is a hydraulic valve that can control the output modulated flow rate and pressure through a closed-loop control method under the control of an analog electrical signal. It has the advantages of fast dynamic response, high control accuracy, and long service life. It is widely used in high-precision mechatronic systems, aerospace, ships, metallurgy, chemical engineering, and other fields, as well as in the electro-hydraulic servo control systems of large test equipment.

[0003] According to the different movement modes of the spool in the valve body, servo valves can be divided into sliding servo valves and rotary servo valves. A rotary servo valve controls the pressure, flow rate, and flow direction of a liquid by controlling the rotation direction and rotation angle of the spool in the valve body. During the control process, there is no need for the axial movement of the spool, and no external leakage will occur. At the same time, the spool can move directly driven by a servo motor without the need for the conversion between rotary motion and linear motion, having the advantages of small leakage, stable operation, and high control accuracy. According to the different spool drive methods, servo valves can be divided into two-stage servo valves and direct-drive servo valves. A direct-drive servo valve uses a servo drive device to directly drive the spool to move, having the advantages of a simpler valve structure, high control reliability, and long service life.

[0004] For existing rotary direct-drive servo valves, a servo motor is usually integrated on the valve body, and the servo motor and the spool are connected to each other through a transmission connection structure, which affects the drive efficiency and drive accuracy of the spool. For existing rotary direct-drive servo valves, a reliable seal is required between the servo motor and the valve cavity to prevent the hydraulic oil in the valve cavity from penetrating into the servo motor and affecting the normal operation of the servo motor. The frequent operation of the servo motor will generate heat, and the heat dissipation conditions in the working environment of the servo valve are usually poor, which easily leads to an increase in the working temperature of the servo motor. Especially in a high-temperature environment, the accumulation of heat generated by the servo motor easily leads to a decrease in motor efficiency. Summary of the Utility Model

[0005] In order to improve the drive efficiency and control accuracy of the servo valve, this application provides a wet rotary direct-drive servo valve.

[0006] The wet rotary direct-drive servo valve provided by this application adopts the following technical solutions:

[0007] A wet direct-drive rotary servo valve includes a valve body, a servo drive mechanism housing, a rotor spool, and a servo drive mechanism. The valve body is provided with a plurality of hydraulic oil ports, and internally provided with a plurality of valve body cavities respectively communicating with the hydraulic oil ports. The servo drive mechanism housing is arranged at one end of the valve body and internally provided with a drive cavity. The rotor spool includes an integrally formed spool portion and a rotor portion. The spool portion is rotatably arranged in the valve body to be able to change the communication state between the valve body cavities. The rotor portion and the servo drive mechanism are correspondingly arranged in the drive cavity, and the rotor portion can be rotated under the drive of the servo drive mechanism. The drive cavity communicates with the valve body cavity.

[0008] By adopting the above technical solution, by using the spool portion rotatably arranged in the valve body, the on-off and the size of the flow area between different valve body cavities can be changed, so that the flow rate, flow direction and pressure of the liquid can be controlled, and thus the flow direction and flow rate of the hydraulic oil flowing to different hydraulic oil ports can be controlled. By using the rotor portion of the rotor spool, the rotor spool can be rotated under the drive of the servo drive mechanism, so that the spool portion of the rotor spool rotates, forming the rotation of the spool portion directly driven by the servo drive mechanism, avoiding setting a transmission connection structure between the spool and the drive shaft of the servo motor, improving the transmission accuracy and transmission efficiency, thus improving the control accuracy of the servo valve and being beneficial to reducing the response time of the servo valve. By the setting that the drive cavity communicates with the valve body cavity, the servo drive mechanism and the rotor portion can be immersed in the hydraulic oil, and the hydraulic oil is used to dissipate heat from the servo drive mechanism, improving the heat dissipation effect of the servo drive mechanism and ensuring the drive efficiency of the servo drive mechanism.

[0009] In a specific feasible implementation, the servo drive mechanism includes a stator and a circuit connection board. The stator includes a plurality of independent stator segments. The plurality of stator segments are spliced together into a ring shape. Each stator segment is provided with a stator segment coil. The stator segment coils are connected to the circuit connection board in a set manner to form a stator coil in combination.

[0010] By adopting the above technical solution, using the stator formed by splicing a plurality of independent stator segments is beneficial to reducing the size of the stator slot opening, improving the slot fill factor, thus being able to effectively reduce the cogging torque fluctuation of the drive motor, significantly improving the power density, and also being able to improve the control accuracy and power output of the drive motor and the servo valve.

[0011] In a specific feasible implementation, the wet direct-drive rotary servo valve of the present application further includes an end cover. The control board housing is fixed on the side of the servo drive mechanism housing opposite to the valve body. The servo drive mechanism further includes a magnetic encoder, a sealing cover, and a PCBA. The magnetic encoder is arranged at the end of the rotor part. The sealing cover is fixed at the end of the servo drive mechanism housing to form a seal between the servo drive mechanism housing and the control board housing. The PCBA is arranged inside the control board housing, and an electrical plug is arranged on the control board housing. The electrical plug is electrically connected to the PCBA.

[0012] By adopting the above technical solution, by using the magnetic encoder arranged at the end of the rotor part, the angular displacement of the rotor spool can be feedback in real time, so that the rotation angle of the rotor spool can be closed-loop controlled through the servo control circuit, forming an accurate control of the flow area of the valve port and improving the control accuracy of the servo valve. By using the sealing cover fixed at the end of the housing, an isolation between the servo drive mechanism housing and the control board housing can be formed. While ensuring that hydraulic oil enters the inside of the servo drive mechanism housing to immerse the stator coil, it can prevent the hydraulic oil from entering the control board housing and affecting the electronic control circuit on the PCBA.

[0013] In a specific feasible implementation, the rotor part includes a rotor core shaft, a magnet mounting post, and a permanent magnet. The rotor core shaft is connected to the spool part. The magnet mounting post is fixed on the rotor core shaft. A plurality of magnet mounting holes are arranged on the magnet mounting post. The plurality of magnet mounting holes are arranged axially on the outer periphery of the magnet mounting post and are evenly arranged in the circumferential direction of the magnet mounting post. The permanent magnet is fixed in the magnet mounting hole.

[0014] By adopting the above technical solution, by using the magnet mounting post arranged on the rotor core shaft, the setting diameter of the permanent magnet can be effectively increased, the torque acting on the permanent magnet can be increased, and the driving efficiency of the rotor can be improved. By using the permanent magnet fixed in the magnet mounting hole, the permanent magnet can be accurately positioned and reliably fixed, eliminating the risk of shedding of the traditional tile-shaped permanent magnet and ensuring the reliability of the driving motor and the valve function.

[0015] In a specific feasible implementation, a connecting oil groove is arranged on the outer peripheral surface of the spool part. The bottom surface of the connecting oil groove is formed by a combination of different planes and / or curved surfaces. When the spool part is in different rotation states, the connecting oil groove can form different communication states with different valve body cavities, constituting different valve position functions.

[0016] By adopting the above technical solution, by using the connecting oil groove formed by the combination of different planes and / or curved surfaces on the outer peripheral surface of the valve core part, the hydraulic torque formed by the flow of hydraulic oil on the valve core part can be reduced, the load of the servo drive mechanism can be reduced, and the servo valve can work more stably.

[0017] In a specific feasible embodiment, the wet direct-drive rotary servo valve of the present application further includes a valve sleeve. A main valve hole communicating with the valve body cavity is provided inside the valve body. The valve sleeve is fixed in the main valve hole. The valve core part is rotatably arranged in the valve sleeve. A plurality of valve sleeve holes respectively communicating different valve body cavities with different connecting oil grooves are provided on the side wall of the valve sleeve.

[0018] By adopting the above technical solution, by using the setting that the valve sleeve is fixed in the main valve hole and the valve core part is rotatably arranged in the valve sleeve, the valve port area between the valve sleeve hole on the side wall of the valve sleeve and the connecting oil groove on the surface of the valve core part can be accurately controlled, and the flow control accuracy of the servo valve can be improved.

[0019] In a specific feasible embodiment, a valve sleeve hole is provided at the connection end of the servo drive mechanism housing and the valve body. One end of the valve sleeve is fixed in the valve sleeve hole. A drainage groove communicating the valve body cavity with the drive cavity is provided on the outer peripheral surface of the valve sleeve.

[0020] By adopting the above technical solution, by using the drainage groove provided on the outer peripheral surface of the valve sleeve and communicating the valve body cavity with the drive cavity, a hydraulic oil drainage channel not affected by the valve position state can be formed, the hydraulic oil can be stably drained into the drive cavity, the stator coil can be cooled, the heat dissipation effect of the stator coil can be improved, and the working stability of the stator coil under high temperature and high load conditions can be improved.

[0021] In a specific feasible embodiment, the hydraulic oil ports on the valve body include a P port, a T port, an A port, and a B port. The valve body cavities include a P cavity, a T cavity, an A cavity, and a B cavity. The P cavity, T cavity, A cavity, and B cavity are respectively communicated with the P port, T port, A port, and B port. The valve sleeve holes include a valve sleeve P hole, a valve sleeve T hole, a valve sleeve A hole, and a valve sleeve B hole. The valve sleeve P hole, valve sleeve T hole, valve sleeve A hole, and valve sleeve B hole are respectively communicated with the P cavity, T cavity, A cavity, and B cavity.

[0022] By adopting the above technical solution, by using the P port, T port, A port, and B port provided on the valve body, they can be respectively connected to the oil pump, return oil tank of the external hydraulic system, and two oil ports of the hydraulic working element, and the external hydraulic working element can be driven to form different working states. By using the valve sleeve P hole, valve sleeve T hole, valve sleeve A hole, and valve sleeve B hole provided on the valve sleeve, different connection forms can be formed with the connecting oil grooves on the rotor part, forming different valve position states, thereby controlling the on-off and oil supply direction of the oil circuit of the hydraulic working element.

[0023] In a specific feasible embodiment, the valve sleeve P holes include a valve sleeve P1 hole, a valve sleeve P2 hole, a valve sleeve P3 hole, and a valve sleeve P4 hole; the valve sleeve T holes include a valve sleeve T1 hole, a valve sleeve T2 hole, a valve sleeve T3 hole, and a valve sleeve T4 hole; the valve sleeve A holes include a valve sleeve A1 hole and a valve sleeve A2 hole; the valve sleeve B holes include a valve sleeve B1 hole and a valve sleeve B2 hole. The valve sleeve P1 hole, the valve sleeve T1 hole, the valve sleeve A1 hole, the valve sleeve P2 hole, the valve sleeve T2 hole, and the valve sleeve A2 hole are sequentially arranged at the same axial position of the valve sleeve. The valve sleeve T3 hole, the valve sleeve P3 hole, the valve sleeve B1 hole, the valve sleeve T4 hole, the valve sleeve P4 hole, and the valve sleeve B2 hole are sequentially arranged at another axial position of the valve sleeve. The connecting oil grooves on the valve core portion include a first connecting oil groove, a second connecting oil groove, a third connecting oil groove, and a fourth connecting oil groove. The first connecting oil groove and the second connecting oil groove are oppositely arranged on the outer peripheral surface of the valve core portion and are connected through a first oil groove connecting hole. The third connecting oil groove and the fourth connecting oil groove are oppositely arranged on the outer peripheral surface of the valve core portion and are connected through a first oil groove connecting hole and also through a second oil groove connecting hole. The first connecting oil groove and the second connecting oil groove are correspondingly arranged with the valve sleeve P1 hole, the valve sleeve T1 hole, the valve sleeve A1 hole, the valve sleeve P2 hole, the valve sleeve T2 hole, and the valve sleeve A2 hole. The third connecting oil groove and the fourth connecting oil groove are correspondingly arranged with the valve sleeve T3 hole, the valve sleeve P3 hole, the valve sleeve B1 hole, the valve sleeve T4 hole, the valve sleeve P4 hole, and the valve sleeve B2 hole.

[0024] By adopting the above technical solution, by using the current state and left - right rotation of the valve core portion in the valve sleeve, it can be made that the first connecting oil groove is only connected to the valve sleeve A1 hole, or is simultaneously connected to the valve sleeve A1 hole and the valve sleeve T1 hole, or is simultaneously connected to the valve sleeve A1 hole and the valve sleeve P2 hole; the second connecting oil groove is only connected to the valve sleeve A2 hole, or is simultaneously connected to the valve sleeve A2 hole and the valve sleeve T2 hole, or is simultaneously connected to the valve sleeve P2 hole and the valve sleeve P1 hole; the third connecting oil groove is only connected to the valve sleeve B1 hole, or is simultaneously connected to the valve sleeve B1 hole and the valve sleeve P3 hole, or is simultaneously connected to the valve sleeve B1 hole and the valve sleeve T4 hole; the fourth connecting oil groove is only connected to the valve sleeve B2 hole, or is simultaneously connected to the valve sleeve B2 hole and the valve sleeve P4 hole, or is simultaneously connected to the valve sleeve B2 hole and the valve sleeve T3 hole, forming a neutral state where the servo valve A port and B port are not connected to the P port and T port; a first rotation position state where the A port is connected to the T port and the B port is connected to the P port; a second rotation position state where the A port is connected to the P port and the B port is connected to the T port, forming the function of a three - position four - way reversing valve.

[0025] In a specific feasible embodiment, a ball mounting seat is arranged at the end of the valve core portion. A ball is arranged in the ball mounting seat and is supported on the bottom of the main valve hole through the ball.

[0026] By adopting the above technical solution, by using the steel ball mounting seat arranged at the end of the valve core part, a rotary support with the bottom of the main valve hole can be formed through the steel ball, while improving the position stability of the end of the rotor valve core, improving the rotational flexibility of the rotor valve core, thereby reducing the driving load of the servo drive mechanism and being beneficial to improving the response speed of the rotor valve core.

[0027] In a specific feasible implementation, a first bearing mounting part is arranged at the end position of the valve core part, a second bearing mounting part is arranged at the connection position between the rotor part and the valve core part, a third bearing mounting part is arranged at the end position of the rotor part, and bearings are arranged between the first bearing mounting part and the valve body, between the second bearing mounting part and the housing of the servo drive mechanism, and between the third bearing mounting part and the housing of the servo drive mechanism.

[0028] By adopting the above technical solution, by using three bearings respectively arranged at different positions of the rotor valve core, the bearing capacity of the rotor valve core during load rotation against centrifugal force and vibration can be improved, the friction force between the valve core part and the valve sleeve can be reduced, and the anti-interference ability during the operation of the servo valve can be enhanced.

[0029] In summary, the present application includes at least one of the following beneficial technical effects:

[0030] 1. By using the valve core part and the rotor part respectively arranged at both ends of the rotor valve core, an integrated synchronous movement can be formed between the valve core part and the rotor part, thereby avoiding the connection structure connecting the servo drive mechanism and the valve core in the servo valve, and improving the control accuracy and response speed of the servo valve.

[0031] 2. The hydraulic oil in the valve body cavity is introduced into the drive cavity through the connection channel between the drive cavity and the valve body cavity, the servo drive mechanism is immersed in the hydraulic oil, and the servo drive mechanism is cooled by the hydraulic oil, improving the heat dissipation effect of the servo drive mechanism, improving the thermal stability and reliability of the servo drive mechanism in harsh environments such as high temperature, high pressure and high load, and reducing the risk of overheating of the servo drive mechanism.

[0032] 3. Through the split stator formed by splicing multiple split stators, the size of the stator slot can be better reduced, the slot fill factor can be increased to 90%, the cogging torque fluctuation of the drive motor can be effectively reduced, the power density can be significantly improved, and the control accuracy and power output of the drive motor and the servo valve can also be improved.

[0033] 4. By setting the bottom surface of the connecting oil groove on the outer peripheral surface of the valve core part to a structure formed by a combination of different planes and / or curved surfaces, the hydrodynamic force formed by the flow of hydraulic oil on the valve core part can be reduced, the load of the servo drive mechanism during the rotation of the rotor valve core can be reduced, and the operation of the servo valve can be made more stable.

[0034] 5. By using the first bearing mounting part, the second bearing mounting part, and the third bearing mounting part respectively arranged at the end position of the spool part, the connection position between the spool part and the rotor part, and the end position of the rotor part, multiple bearings can be arranged and supported at different positions of the rotor spool, improving the bearing capacity of the rotor spool against centrifugal force and vibration during the load rotation process, reducing the friction force between the spool part and the valve sleeve, and enhancing the stability and anti-interference ability of the servo valve during operation. Description of the Drawings

[0035] Figure 1 It is a schematic external view of an embodiment of the present application.

[0036] Figure 2 It is a schematic axial sectional view of an embodiment of the present application.

[0037] Figure 3 It is Figure 2 The sectional view in the A-A orientation in

[0038] Figure 4 It is a schematic view of the valve body structure in an embodiment of the present application.

[0039] Figure 5 It is Figure 4 The sectional view in the D-D orientation in

[0040] Figure 6 It is Figure 4 The sectional view in the E-E orientation in

[0041] Figure 7 It is a schematic view of the valve sleeve structure in an embodiment of the present application.

[0042] Figure 8 It is Figure 7 The sectional views in the F-F and G-G orientations in

[0043] Figure 9 It is a schematic external view of the rotor spool in an embodiment of the present application.

[0044] Figure 10 It is a schematic sectional view of the rotor spool in an embodiment of the present application.

[0045] Figure 11 It is Figure 10 The sectional views in the H-H and I-I orientations in

[0046] Figure 12 It is Figure 2 The sectional views of the spool in the B-B and C-C orientations in the zero position state in

[0047] Figure 13 It is a schematic functional principle diagram of the spool in the zero position state in an embodiment of the present application.

[0048] Figure 14 In Figure 2 Figure 3 is a cross-sectional view of the valve core in the B-B and C-C orientations in the first working position state.

[0049] Figure 15 Figure 7 is a functional schematic diagram of the valve core in the first working position state in an embodiment of the present application.

[0050] Figure 16 In Figure 2 Figure 13 is a cross-sectional view of the valve core in the B-B and C-C orientations in the second working position state.

[0051] Figure 17 Figure 17 is a functional schematic diagram of the valve core in the second working position state in an embodiment of the present application.

[0052] Explanation of reference numerals: 1. Valve body; 101. P port; 102. T port; 103. A port; 104. B port; 11. Main valve hole; 12. P chamber; 13. T chamber; 14. A chamber; 15. B chamber; 2. Housing; 21. Valve sleeve hole; 3. Rotor valve core; 31. Valve core part; 311. First connecting oil groove; 312. Second connecting oil groove; 313. Third connecting oil groove; 314. Fourth connecting oil groove; 315. First oil groove connecting hole; 316. Second oil groove connecting hole; 317. Ball mounting seat; 318. First bearing mounting part; 32. Rotor part; 321. Rotor core shaft; 322. Magnet mounting post; 323. Permanent magnet; 324. Second bearing mounting part; 325. Third bearing mounting part; 33. Bearing; 4. Servo drive mechanism; 41. Stator; 411. Stator split; 412. Stator split coil; 42. Circuit connection board; 43. Magnetic encoder; 44. Sealing cover; 45. PCBA; 5. End cover; 51. Electrical plug; 6. Valve sleeve; 601. Drainage groove; 61. Valve sleeve P port; 611. Valve sleeve P1 port; 612. Valve sleeve P2 port; 613. Valve sleeve P3 port; 614. Valve sleeve P4 port; 62. Valve sleeve T port; 621. Valve sleeve T1 port; 622. Valve sleeve T2 port; 623. Valve sleeve T3 port; 624. Valve sleeve T4 port; 63. Valve sleeve A port; 631. Valve sleeve A1 port; 632. Valve sleeve A2 port; 64. Valve sleeve B port; 641. Valve sleeve B1 port; 642. Valve sleeve B2 port. Detailed implementation manners

[0053] The following will describe in detail the detailed implementation manners of the present application with reference to the accompanying drawings. It should be understood that the detailed implementation manners described herein are only for explaining and illustrating the present application, and are not used to limit the present application.

[0054] In the description of the present application, it should be noted that unless otherwise clearly specified and limited, the terms "arrangement" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the communication inside two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0055] In this specification, the terms "first", "second", "third", and "fourth" are only used for the purpose of description and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Therefore, the features defined with "first", "second", "third", and "fourth" may explicitly or implicitly include one or more of the said features.

[0056] An embodiment of the wet direct drive type rotary servo valve of the present application, as Figures 1 to 3 shown, includes a valve body 1, a servo drive mechanism housing 2, a rotor spool 3, and a servo drive mechanism 4. The valve body 1 is provided with a liquid circuit interface of the wet direct drive type rotary servo valve of the present application, and a pressure liquid flow channel forming a valve structure is arranged inside. The valve body 1 adopts generative AI design and is formed by 3D printing, which can form a flow channel with equal wall thickness and a structure without process holes, can significantly reduce raw materials, and significantly reduce the processing amount, and has the advantages of light weight, small volume, and high power density. The flow channel inside the valve body 1 is processed by a grinding flow process, the flow channel is smooth and continuous, the pressure loss during the flow of the pressure liquid is small, it is energy-saving, and the flow capacity is large. Compared with traditional servo valves of the same specification, the rated flow of the servo valve using the valve body 1 of the present application can be increased by 1-2 times. Of course, the valve body 1 can also be processed and formed by other existing processing methods.

[0057] A plurality of hydraulic oil ports connected to an external hydraulic system are arranged on the valve body 1, and the flow direction and flow rate of the hydraulic oil input by the external hydraulic system are controlled through the plurality of hydraulic oil ports. A plurality of valve body cavities are arranged inside the valve body 1, and the plurality of valve body cavities are respectively communicated with the plurality of hydraulic oil ports.

[0058] The servo drive mechanism housing 2 is used to carry the drive mechanism of the wet direct drive type rotary servo valve of the present application. Generally, the liquid circuit interface is arranged on the end face at one end of the valve body 1, and the servo drive mechanism housing 2 is fixed to the end at the other end of the valve body 1. A drive cavity for installing a drive mechanism for driving the rotor spool 3 to rotate is arranged inside the housing.

[0059] The rotor spool valve 3 is an integrally formed structural part made of suitable materials such as metal, ceramic, or polymer materials. One end of the rotor spool valve 3 is processed into a spool part 31 for controlling the flow direction and flow rate of hydraulic oil, and the other end is processed into a rotor part 32 for driving the rotation of the rotor spool valve 3. The spool part 31 is installed inside the valve body 1 and can rotate within the valve body 1. A plurality of spool oil grooves recessed into the interior of the spool part 31 are provided on the outer peripheral surface of the spool part 31. When the rotor spool valve 3 rotates to different angular states within the valve body 1, the spool oil grooves can form different degrees of communication states or isolation states with different valve cavities within the valve body 1, thereby controlling the flow rate and flow direction of the hydraulic oil flowing into the valve body 1 through the hydraulic oil port. The rotor part 32 is installed in the drive cavity inside the servo drive mechanism housing 2, and a power component adapted to the servo drive mechanism 4 is provided on the rotor part 32, so that the rotor part 32 can generate a rotational motion under the action of the servo drive mechanism 4, driving the spool part 31 at the other end to rotate within the valve body 1.

[0060] The servo drive mechanism 4 is fixed in the drive cavity inside the servo drive mechanism housing 2, located at the outer peripheral part of the rotor part 32, and is arranged corresponding to the rotor part 32, so that the servo drive mechanism 4 and the rotor part 32 are combined to form a servo drive device similar to a conventional servo motor. Generally, a rotor structure composed of a coil or a permanent magnet is provided on the rotor part 32, and a stator coil is provided at a part of the servo drive mechanism 4 located around the rotor structure. When an electric current is passed through the stator coil, the rotor structure can be driven to rotate, and the rotor structure drives the rotor spool valve 3 to rotate relative to the servo drive mechanism 4, forming a direct drive for the rotor spool valve 3. A servo control circuit is provided in the servo drive mechanism 4, and the rotation of the rotor structure can be closed-loop controlled by using the servo control circuit, forming an accurate control of the rotation position of the rotor spool valve 3.

[0061] A hydraulic oil connection passage is provided between the drive cavity and the valve cavity, so that the hydraulic oil in the valve cavity can flow into the drive cavity along the connection passage, immersing both the rotor part 32 and the servo drive mechanism 4 in the hydraulic oil. When the servo drive mechanism 4 works, the heat generated by the stator coil under the action of the drive current is dissipated into the hydraulic oil and can be dissipated along with the flow of the hydraulic oil. Compared with the dry servo drive device of the traditional servo valve, the heat dissipation effect of the stator coil can be greatly improved. When the servo valve works in harsh environments such as high temperature, high pressure, and high load, the setting of immersing the rotor part 32 and the servo drive mechanism 4 in the hydraulic oil can not only improve the heat dissipation effect and reduce the risk of overheating of the stator coil, but also improve the insulation performance of the stator coil, making the operation of the servo drive device more reliable and stable.

[0062] In some embodiments of the wet direct drive rotary servo valve of the present application, such as Figure 2 and Figure 3As shown, the servo drive mechanism 4 includes a stator 41 and a circuit connection plate 42. Among them, the stator 41 is formed by splicing multiple independent stator segments 411 together. Specifically, each stator segment 411 has an independent iron core segment. Winding coil slots are provided in the middle of both sides of the iron core segment, and stator segment coils 412 are wound in the winding coil slots. After the stator segment coils 412 are wound, multiple iron core segments are connected to each other by welding, bonding, riveting, or other connection methods such as through an external connection structure from both the inside and outside of the winding coil slots, so that the multiple stator segments 411 are spliced together to form an annular stator 41.

[0063] The circuit connection plate 42 is arranged in the drive cavity and is located at one end of the stator 41 away from the valve body 1. The stator segment coils 412 on each stator segment 411 are all connected to the circuit connection plate 42 and are connected to each other in a set manner on the circuit connection plate 42, so that the stator segment coils 412 on different electronic segments 411 are connected in series and parallel in a set manner and are combined with each other to form a stator coil with a set winding direction. The specific number of stator segments 411 is determined according to the design requirements of the servo drive device.

[0064] The stator 41 formed by welding multiple stator segments 411 is welded after the stator segment coils 412 are wound. After the stator 41 is welded and formed, there is no need to wind the stator coil. Compared with the traditional integral stator iron core that needs to wind the stator coil through the stator slot opening after the stator iron core is processed and formed, the width of the stator slot opening can be set smaller, and the slot fill factor of the stator iron core can also be set higher, usually reaching 90%, thereby reducing the cogging torque ripple of the servo drive device and effectively increasing the power density. In addition, the split design of the stator 41 can also improve the control accuracy and power output of the servo drive device and the servo valve.

[0065] In a preferred embodiment of the wet direct-drive rotary servo valve of the present application, as Figure 1 and Figure 2 shown, the wet direct-drive rotary servo valve of the present application further includes a control board housing 5. The control board housing 5 is fixed on the servo drive mechanism housing 2, usually fixed at one end of the servo drive mechanism housing 2 opposite to the valve body 1, and forms a strip-shaped structure with the same cross-sectional shape as the servo drive mechanism housing 2 and the valve body 1.

[0066] The servo drive mechanism 4 is also provided with a magnetic encoder 43, a seal cover 44 and a PCBA 45. Generally, a magnetic encoder mounting seat is fixedly connected to the end of the rotor part 32. A magnetic encoder fixing hole is arranged on the end face of the magnetic encoder mounting seat, and the magnetic encoder 43 is fixed in the magnetic encoder fixing hole. The magnetic encoder mounting seat and the magnetic encoder 43 generally extend out of the end of the servo drive mechanism housing 2 and protrude into the interior of the control board housing 5. The seal cover 44 is fixed to the end of the servo drive mechanism housing 2 to cover the magnetic encoder mounting seat and the magnetic encoder 43 within the seal cover 44, forming a seal between the servo drive mechanism housing 2 and the control board housing 5 outside the magnetic encoder 43, so that the magnetic encoder mounting seat and the magnetic encoder 43 are located in a sealed space communicating with the drive cavity. Generally, a housing fixing plate is arranged at the end of the servo drive mechanism housing 2. A magnetic encoder mounting hole is arranged in the middle of the housing fixing plate. The magnetic encoder mounting seat passes through the magnetic encoder mounting hole and is fixed to the end of the rotor part 32. The housing fixing plate is fixed to the end of the servo drive mechanism housing 2, and a sealing ring is arranged between the housing fixing plate and the servo drive mechanism housing 2 to ensure reliable sealing between the servo drive mechanism housing 2 and the housing fixing plate. The end of the seal cover 44 is fixed to the housing fixing plate, and a sealing ring is arranged between the seal cover 44 and the housing fixing plate to ensure reliable sealing between the seal cover 44 and the housing fixing plate. In this way, reliable sealing between the drive cavity and the interior space of the control board housing 5 can be ensured, preventing the leakage of hydraulic oil in the drive cavity.

[0067] The PCBA (printed circuit board assembly) 45 is arranged outside the seal cover 44 within the control board housing 5, and a servo control circuit is arranged on the PCBA. The PCBA 45 is electrically connected to the stator coil, usually electrically connected to the stator coil through a circuit connection board 42. The servo control circuit therein can control the current in the stator coil to form a driving force for the rotor structure on the rotor part 32, driving the rotor spool 3 to rotate. An electrical plug 51 connected to an external power supply and a control system is arranged on the control board housing 5. The electrical plug 51 is connected to the PCBA 45, so that the operation of the servo valve can be controlled by using an external control system. A magnetic encoder detection element capable of detecting the rotation state of the magnetic encoder 43 is arranged at a position corresponding to the magnetic encoder 43 on the PCBA 45. The magnetic encoder detection element can accurately detect the rotation angle state of the magnetic encoder 43, which also reflects the rotation angle state of the rotor spool 3, and controls the current in the stator coil according to the rotor angle state of the rotor spool 3, realizing precise closed-loop control of the rotation position of the rotor spool 3 through the servo control circuit. In this way, the size of the valve port between the connecting oil groove on the spool part 31 and the valve body cavity can be precisely controlled, thereby realizing precise control of the flow rate.

[0068] In some embodiments of the wet direct drive rotary servo valve of the present application, such as Figure 2 and Figure 3As shown, the rotor part 32 includes a rotor core shaft 321, magnet mounting posts 322, and permanent magnets 323. The rotor core shaft 321 is a rotating long shaft integrally connected to the valve core part 31. The rotor core shaft 321 passes through the end of the servo drive mechanism housing 2 and enters the drive cavity.

[0069] The magnet mounting posts 322 are cylindrical structures with central axis holes. The magnet mounting posts 322 are arranged in the drive cavity, fixed on the rotor core shaft 321 through the central axis holes, and can rotate together with the rotor core shaft 321. A plurality of magnet mounting holes are provided on the magnet mounting posts 322. The plurality of magnet mounting holes are arranged in a direction parallel to the central axis hole, and are arranged on the outer peripheral part of the magnet mounting posts 322, adjacent to the outer peripheral surface of the magnet mounting posts 322, so that the gap between the permanent magnets 323 mounted in the magnet mounting holes and the stator 41 is smaller. Moreover, the plurality of magnet mounting holes are closely arranged with the smallest possible gap in the circumferential direction of the magnet mounting posts 322 and are evenly arranged, thereby reducing the gap between adjacent permanent magnets 323 and improving the rotational stability of the rotor part 32. The specific number of magnet mounting holes provided is determined according to the design requirements of the servo drive device.

[0070] A permanent magnet 323 is fixedly arranged in each magnet mounting hole. The arrangement of embedding the permanent magnet 323 in the magnet mounting hole can facilitate the installation and fixation of the permanent magnet 323 on the rotor, improve the positioning accuracy of the permanent magnet 323, and eliminate the risk of the permanent magnet 323 falling off. In the existing servo valve, the permanent magnet in the servo motor adopts a tile-shaped structure fixed on the rotor surface, and the fixing reliability is poor. During long-term use in a vibration environment, the permanent magnet is likely to fall off. Once the permanent magnet falls off, it is easy to cause damage to the servo motor and the loss of the function of the servo valve.

[0071] In some embodiments of the wet direct drive rotary servo valve of the present application, as Figures 9 to 11 shown, a connecting oil groove is provided on the outer peripheral surface of the valve core part 31. The connecting oil groove is recessed from the outer peripheral surface of the valve core part 21 towards the inside, and the bottom surface of the connecting oil groove can be formed by different planes and / or surface combinations. Generally, the two sides of the bottom surface of the oil groove along the length direction are two different planes and / or curved surfaces respectively. As a preferred embodiment, two inwardly recessed arc cylindrical surfaces are respectively formed on both sides of the bottom surface of the oil groove, and the two arc cylindrical surfaces are connected in the middle of the connecting oil groove to form a longitudinal convex rib, so that the shape of the connecting oil groove in the cross section is a smooth M shape. Specifically, the two sides of the connecting oil groove extend towards the inside of the valve core part 31 in parallel to form the side surfaces of the connecting oil groove; after extending to a certain depth, they turn and extend towards each other to form the bottom surface of the connecting oil groove. The two sides of the bottom surface of the connecting oil groove form a circular arc recessed towards the inside of the bottom surface while extending towards the middle, and extend towards the outside of the bottom surface and are connected to each other in the middle of the bottom surface to form a protrusion towards the outside of the bottom surface, forming a smooth M-shaped cross-sectional shape.

[0072] When the spool part 31 rotates to different rotation states inside the valve body 1, different parts in the width direction of the connecting oil groove can communicate with different valve body cavities inside the valve body 1, enabling the hydraulic oil to flow along the width direction of the connecting oil groove in the connecting oil groove. The M-shaped cross-sectional shape of the connecting oil groove can reduce the hydrodynamic torque of the hydraulic oil flow on the wall of the connecting oil groove, reduce the rotation load of the spool part, and make the rotation of the spool part more stable. Moreover, as the spool part 31 rotates, the connecting oil groove can form a communication state with different valve orifice sizes between the valve body cavities, and while forming different valve position functions of the servo valve, it can also precisely control the flow rate of the hydraulic oil.

[0073] Compared with the traditional rectangular or circular arc shape of the bottom surface of the connecting oil groove, the smooth M-shaped bottom shape of the groove can reduce the hydrodynamic force on the spool part 31 when the hydraulic oil flows between different valve body cavities through the connecting oil groove, reduce the driving load when the servo drive device drives the spool part 31 to rotate, and make the operation of the servo valve more stable.

[0074] In a preferred embodiment of the wet direct drive rotary servo valve of the present application, as Figure 2 shown, the wet direct drive rotary servo valve of the present application further includes a valve sleeve 6. As Figures 4 to 6 shown, a main valve hole 11 communicating with different valve body cavities is provided inside the valve body 1. As Figure 7 and Figure 8 shown, a plurality of valve sleeve holes are provided on the side wall of the valve sleeve 6. The valve sleeve 6 is fixed in the main valve hole 11, so that different valve sleeve holes on the valve sleeve 6 communicate with different valve body cavities inside the valve body 1.

[0075] The spool part 31 is rotatably arranged in the valve sleeve 6. When the spool part 31 is in different rotation states, the connecting oil groove on the spool part 31 communicates with different valve sleeve holes on the side wall of the valve sleeve 6. By setting the valve sleeve holes on the valve sleeve 6, the valve orifice size of the servo valve can be more precisely controlled.

[0076] As a specific implementation manner of the wet direct drive rotary servo valve of the present application, as Figure 2 and Figure 7 shown, a valve sleeve hole 21 is provided on the end surface where the servo drive mechanism housing 2 is connected to the valve body 1. One end of the valve sleeve 6 extends into the valve sleeve hole 21 and is fixed on the side wall of the valve sleeve hole 21. An axially extending drainage groove 601 is provided on the outer peripheral surface of the valve sleeve 6. After the valve sleeve 6 is fixed in the valve sleeve hole 21, one end of the drainage groove 601 communicates with the valve body cavity, and the other end communicates with the drive cavity, enabling the hydraulic oil in the drive cavity to flow into the valve body cavity through the drainage groove 601.

[0077] Specifically, after the valve sleeve 6 is fixed in the valve sleeve hole 21, one end of the drainage groove 601 is preferably communicated with the A chamber 14, and the other end is communicated with the driving chamber. As the servo driving mechanism 4 drives the rotor valve core 3 to rotate, the hydraulic pressure in the A chamber 14 changes between the high hydraulic pressure in the P chamber 12 and the low hydraulic pressure in the T chamber 13. The change of the hydraulic pressure in the A chamber 14 further promotes the flow of the hydraulic oil between the valve body chamber and the driving chamber, and further improves the heat dissipation effect on the stator coil.

[0078] In some embodiments of the wet direct drive rotary servo valve of the present application, as Figures 1 to 8 shown, the hydraulic oil ports provided on the end face of the valve body 1 include a P port 101, a T port 102, an A port 103, and a B port 104. The valve body chambers provided inside the valve body 1 include a P chamber 12, a T chamber 13, an A chamber 14, and a B chamber 15. Among them, the P chamber 12 is communicated with the P port 101, the T chamber 13 is communicated with the T port 102, the A chamber 14 is communicated with the A port 103, and the B chamber 15 is communicated with the B port 104. The valve sleeve holes provided on the valve sleeve 6 include a valve sleeve P hole 61, a valve sleeve T hole 62, a valve sleeve A hole 63, and a valve sleeve B hole 64. After the valve sleeve 6 is installed in the main valve hole 11, the valve sleeve P hole 61 is communicated with the P chamber 12, the valve sleeve T hole 62 is communicated with the T chamber 13, the valve sleeve A hole 63 is communicated with the A chamber 14, and the valve sleeve B hole 64 is communicated with the B chamber 15. And inside the valve body 1, the P chamber 12, the T chamber 13, the A chamber 14, and the B chamber 15 are isolated from each other. In this way, by rotating the valve core part 31 inside the valve sleeve 6 and switching the connection relationship between the connecting oil grooves on the valve core part 31 and the valve sleeve P hole 61, the valve sleeve T hole 62, the valve sleeve A hole 63, and the valve sleeve B hole 64, it is possible to make the valve sleeve A hole 63 communicate with the valve sleeve P hole 61 or the valve sleeve T hole 62, and the size of the flow area between them. At the same time, the valve sleeve B hole 64 communicates with the valve sleeve T hole 62 or the valve sleeve P hole 61, and the size of the flow area between them, so as to switch the flow direction and flow rate of the hydraulic oil passing through the A port 103 and the B port 104.

[0079] In a preferred embodiment of the wet direct drive rotary servo valve of the present application, as Figures 7 to 11 shown, the valve sleeve holes on the valve sleeve 6 are respectively provided on two circumferential surfaces at different axial positions of the valve sleeve 6. The valve sleeve P hole 61 includes a valve sleeve P1 hole 611, a valve sleeve P2 hole 612, a valve sleeve P3 hole 613, and a valve sleeve P4 hole 614. The valve sleeve T hole 62 includes a valve sleeve T1 hole 621, a valve sleeve T2 hole 622, a valve sleeve T3 hole 623, and a valve sleeve T4 hole 624. The valve sleeve A hole 63 includes a valve sleeve A1 hole 631 and a valve sleeve A2 hole 632. The valve sleeve B hole 64 includes a valve sleeve B1 hole 641 and a valve sleeve B2 hole 642.

[0080] Among them, the valve sleeve P1 hole 611, the valve sleeve T1 hole 621, the valve sleeve A1 hole 631, the valve sleeve P2 hole 612, the valve sleeve T2 hole 622, and the valve sleeve A2 hole 632 are sequentially arranged on the circumferential surface of the valve sleeve 6 at the same axial position. The valve sleeve T3 hole 623, the valve sleeve P3 hole 613, the valve sleeve B1 hole 641, the valve sleeve T4 hole 624, the valve sleeve P4 hole 614, and the valve sleeve B2 hole 642 are sequentially arranged on the circumferential surface of the valve sleeve 6 at another axial position. The valve sleeve P1 hole 611, the valve sleeve P2 hole 612, the valve sleeve P3 hole 613, and the valve sleeve P4 hole 614 communicate with the P chamber 12 at different positions inside the valve body 1. The valve sleeve T1 hole 621, the valve sleeve T2 hole 622, the valve sleeve T3 hole 623, and the valve sleeve T4 hole 624 communicate with the T chamber 13 at different positions inside the valve body 1. Both the valve sleeve A1 hole 631 and the valve sleeve A2 hole 632 communicate with the A chamber 14 inside the valve body 1. Both the valve sleeve B1 hole 641 and the valve sleeve B2 hole 642 communicate with the B chamber 15 inside the valve body 1.

[0081] The connecting oil grooves on the valve core part 31 include a first connecting oil groove 311, a second connecting oil groove 312, a third connecting oil groove 313, and a fourth connecting oil groove 314. The first connecting oil groove 311, the second connecting oil groove 312, the third connecting oil groove 313, and the fourth connecting oil groove 314 all extend on the outer circumferential surface of the valve core part 31 in a direction parallel to the rotation axis of the valve core part 31. Among them, the first connecting oil groove 311 and the second connecting oil groove 312 are arranged on the circumferential surface of the valve core part 31 at one axial position and are oppositely arranged in the circumferential direction. A plurality of first oil groove connecting holes 315 are provided at different positions in the length direction of the first connecting oil groove 311 and the second connecting oil groove 312, and the first oil groove connecting holes 315 connect the first connecting oil groove 311 and the second connecting oil groove 312. The third connecting oil groove 313 and the fourth connecting oil groove 314 are arranged on the circumferential surface of the valve core part 31 at another axial position and are oppositely arranged in the circumferential direction. A plurality of second oil groove connecting holes 316 are provided at different positions in the length direction of the third connecting oil groove 313 and the fourth connecting oil groove 314, and the second oil groove connecting holes 316 connect the third connecting oil groove 313 and the fourth connecting oil groove 314.

[0082] When the valve core part 31 is installed in the valve sleeve 6, the first connecting oil groove 311 and the second connecting oil groove 312 are in positions corresponding to the valve sleeve P1 hole 611, the valve sleeve T1 hole 621, the valve sleeve A1 hole 631, the valve sleeve P2 hole 612, the valve sleeve T2 hole 622, and the valve sleeve A2 hole 632. The third connecting oil groove 313 and the fourth connecting oil groove 314 are in positions corresponding to the valve sleeve T3 hole 623, the valve sleeve P3 hole 613, the valve sleeve B1 hole 641, the valve sleeve T4 hole 624, the valve sleeve P4 hole 614, and the valve sleeve B2 hole 642.

[0083] When the rotor valve core 3 is in the original position, as Figure 12As shown, the first connecting oil groove 311 is only connected to the valve sleeve A1 hole 631, and the second connecting oil groove 312 is only connected to the valve sleeve A2 hole 632. The valve sleeve P1 hole 611, the valve sleeve T1 hole 621, the valve sleeve P2 hole 612, and the valve sleeve T2 hole 622 are all closed by the outer peripheral surface of the valve core part 31. At the same time, the third connecting oil groove 313 is only connected to the valve sleeve B1 hole 641, and the fourth connecting oil groove 314 is only connected to the valve sleeve B2 hole 642. The valve sleeve T3 hole 623, the valve sleeve P3 hole 613, the valve sleeve T4 hole 624, and the valve sleeve P4 hole 614 are all closed by the outer peripheral surface of the valve core part 31. At this time, the wet direct drive rotary servo valve of the present application is in the zero position state as shown in Figure 13 , and there is a cut-off state between the P port 101, the T port 102, the A port 103, and the B port 104, and no hydraulic oil flows through the P port 101, the T port 102, the A port 103, and the B port 104.

[0084] When the rotor valve core 3 rotates counterclockwise by a certain angle, as shown in Figure 14 , the first connecting oil groove 311 is simultaneously connected to the valve sleeve A1 hole 631 and the valve sleeve T1 hole 621, and the second connecting oil groove 312 is simultaneously connected to the valve sleeve A2 hole 632 and the valve sleeve T2 hole 622. The valve sleeve P1 hole 611 and the valve sleeve P2 hole 612 are closed by the outer peripheral surface of the valve core part 31. At the same time, the third connecting oil groove 313 is simultaneously connected to the valve sleeve B1 hole 641 and the valve sleeve P3 hole 613, and the fourth connecting oil groove 314 is simultaneously connected to the valve sleeve B2 hole 642 and the valve sleeve P4 hole 614. The valve sleeve T3 hole 623 and the valve sleeve T4 hole 624 are closed by the outer peripheral surface of the valve core part 31.

[0085] At this time, the wet direct drive rotary servo valve of the present application is in the first working position state as shown in Figure 15 . The P port 101 and the B port 104 are in a mutually connected state, and the T port 102 and the A port 103 are in a mutually connected state. The hydraulic oil from the P port 101 flows through the P chamber 12 to the valve sleeve P3 hole 613 and the valve sleeve P4 hole 614 respectively. Among them, the hydraulic oil flowing to the valve sleeve P3 hole 613 flows through the third connecting oil groove 313 to the valve sleeve B1 hole 641; the hydraulic oil flowing to the valve sleeve P4 hole 614 flows through the fourth connecting oil groove 314 to the valve sleeve B2 hole 642. The hydraulic oil from the valve sleeve B1 hole 641 and the valve sleeve B2 hole 642 converges into the B chamber 15 and flows out through the B port 104 to supply oil to the hydraulic working element. The third connecting oil groove 313 and the fourth connecting oil groove 314 arranged in parallel can increase the flow rate of the valve port, and the second oil groove connection hole 316 connected between the third connecting oil groove 313 and the fourth connecting oil groove 314 can balance the oil pressure in the third connecting oil groove 313 and the fourth connecting oil groove 314.

[0086] The oil returning from the hydraulic working element flows into chamber A14 through port A103, and then flows to sleeve A1 hole 631 and sleeve A2 hole 632 respectively. Among them, the hydraulic oil flowing to sleeve A1 hole 631 flows through the first connecting oil groove 311 to sleeve T1 hole 621; the hydraulic oil flowing to sleeve A2 hole 632 flows through the second connecting oil groove 312 to sleeve T2 hole 622. The hydraulic oil from sleeve T1 hole 621 and sleeve T2 hole 622 converges into chamber T13 and returns to the oil tank through port T102. The first connecting oil groove 311 and the second connecting oil groove 312 arranged in parallel can increase the flow rate of the valve port, and the first oil groove connecting hole 315 connected between the first connecting oil groove 311 and the second connecting oil groove 312 can balance the oil pressure in the first connecting oil groove 311 and the second connecting oil groove 312. By controlling the rotation angle of the rotor spool 3, the flow rate of the oil supplied to the hydraulic working element can be controlled.

[0087] When the rotor spool 3 rotates clockwise by a certain angle from the original position, as Figure 16 shown, the first connecting oil groove 311 is simultaneously connected to sleeve A1 hole 631 and sleeve P2 hole 612, and the second connecting oil groove 312 is simultaneously connected to sleeve A2 hole 632 and sleeve P1 hole 611, while sleeve T1 hole 621 and sleeve T2 hole 622 are closed by the outer peripheral surface of the spool part 31. At the same time, the third connecting oil groove 313 is simultaneously connected to sleeve B1 hole 641 and sleeve T4 hole 624, and the fourth connecting oil groove 314 is simultaneously connected to sleeve B2 hole 642 and sleeve T3 hole 623, while sleeve P3 hole 613 and sleeve P4 hole 614 are closed by the outer peripheral surface of the spool part 31.

[0088] At this time, the wet direct-drive rotary servo valve of the present application is in the second working position state as Figure 17 shown. Port P101 and port A103 are in a communicating state with each other, and port T102 and port B104 are in a communicating state with each other. The hydraulic oil from port P101 flows through chamber P12 to sleeve P1 hole 611 and sleeve P2 hole 612 respectively. Among them, the hydraulic oil flowing to sleeve P1 hole 611 flows through the second connecting oil groove 312 to sleeve A2 hole 632; the hydraulic oil flowing to sleeve P2 hole 612 flows through the first connecting oil groove 311 to sleeve A1 hole 631. The hydraulic oil from sleeve A1 hole 631 and sleeve A2 hole 632 converges into chamber A14 and flows out through port A103 to supply oil to the hydraulic working element. The first connecting oil groove 311 and the second connecting oil groove 312 arranged in parallel can increase the flow rate of the valve port, and the first oil groove connecting hole 315 connected between the first connecting oil groove 311 and the second connecting oil groove 312 can balance the oil pressure in the first connecting oil groove 311 and the second connecting oil groove 312.

[0089] The oil return from the hydraulic working element flows into chamber B15 through port B104, and then flows to sleeve B1 hole 641 and sleeve B2 hole 642 respectively. Among them, the hydraulic oil flowing to sleeve B1 hole 641 flows through the third connecting oil groove 313 to sleeve T4 hole 624; the hydraulic oil flowing to sleeve B2 hole 642 flows through the fourth connecting oil groove 314 to sleeve T3 hole 623. The hydraulic oil from sleeve T3 hole 623 and sleeve T4 hole 624 converges into chamber T13 and returns to the fuel tank through port T102. The juxtaposed third connecting oil groove 313 and fourth connecting oil groove 314 can increase the flow rate of the valve port, and the second oil groove connecting hole 315 connected between the third connecting oil groove 313 and the fourth connecting oil groove 314 can balance the oil pressure in the third connecting oil groove 313 and the fourth connecting oil groove 314. By controlling the rotation angle of the rotor spool 3, the flow rate of the oil supplied to the hydraulic working element can be controlled.

[0090] In some embodiments of the wet direct drive rotary servo valve of the present application, such as Figure 2 , Figure 9 and Figure 10 shown, a ball mounting seat 317 is provided at the end of the spool portion 31, and a ball is provided in the ball mounting seat 317. When the spool portion 31 is installed in the main valve hole 11, the ball mounting seat 317 at the end of the rotor spool 3 is rotationally supported on the bottom wall of the main valve hole 11 through the ball. The setting of the ball mounting seat 317 and the ball can provide the rotational flexibility of the rotor spool 3, which is beneficial to improving the response speed of the rotor spool. After optimization, the frequency response of the wet direct drive rotary servo valve of the present application can reach 300HZ, far exceeding that of the traditional structure servo valve.

[0091] A clearance fit is adopted between the spool portion 31 and the valve sleeve 6, so that the rotor spool 3 and the valve sleeve 6 do not contact each other, which can reduce the wear between the rotor spool 3 and the valve sleeve 6 during rotation. Compared with the traditional setting where the servo valve spool is directly supported inside the valve sleeve, it can effectively reduce the wear of the spool and the valve sleeve after long-term use, making the service life and reliability of the wet direct drive rotary servo valve of the present application far exceed that of the traditional servo valve.

[0092] In the wet direct drive rotary servo valve of the present application, such as Figure 2 , Figure 9 and Figure 10As shown in the figure, a first bearing mounting portion 318 is provided at the end position of the spool portion 31, a second bearing mounting portion 324 is provided at the connection between the spool portion 31 and the rotor portion 32, and a third bearing mounting portion 325 is provided at the end position of the rotor portion 32; bearings 33 are provided between the first bearing mounting portion 318 and the valve body 1, between the second bearing mounting portion 324 and the servo drive mechanism housing 2, and between the third bearing mounting portion 325 and the servo drive mechanism housing 2, so that the rotor spool 3 is supported on the valve body 1 and the servo drive mechanism housing 2 by three bearings 33. Compared with the traditional servo valve with one bearing provided at each of the two spools, it can improve the bearing capacity of centrifugal force and vibration during the load-bearing rotation of the rotor spool 3, reduce the friction between the spool portion 31 and the valve sleeve 6, and thus enhance the anti-interference ability of the servo valve during operation.

[0093] In the description of the present application, the description referring to terms such as "one embodiment", "specific embodiment", "preferred embodiment", etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present application, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0094] The above are all the preferred embodiments of the present application, and do not limit the protection scope of the present application accordingly. Therefore, all equivalent changes made according to the structure, shape, and principle of the present application should be covered within the protection scope of the present application.

Claims

1. A wet direct drive rotary servo valve, characterized in that: The invention comprises a valve body (1), a servo drive mechanism housing (2), a rotor valve core (3) and a servo drive mechanism (4); the valve body (1) is provided with a plurality of hydraulic oil ports, and a plurality of valve body cavities respectively connected to the hydraulic oil ports are provided therein; the servo drive mechanism housing (2) is provided at one end of the valve body (1) and a drive cavity is provided therein; the rotor valve core (3) comprises an integrally formed valve core portion (31) and a rotor portion (32); the valve core portion (31) is rotatably provided in the valve body (1) so as to be able to change the connection state between the valve body cavities; the rotor portion (32) and the servo drive mechanism (4) are correspondingly provided in the drive cavity; the rotor portion (32) can rotate under the drive of the servo drive mechanism (4); and the drive cavity is connected to the valve body cavity.

2. The wet direct drive rotary servo valve according to claim 1, characterized in that: The servo drive mechanism (4) comprises a stator (41) and a circuit connection plate (42); the stator (41) comprises a plurality of independent stator lobes (411); the plurality of stator lobes (411) are spliced ​​together to form a ring; each of the stator lobes (411) is provided with a stator lobe coil (412); the stator lobe coil (412) is connected to the circuit connection plate (42) in a set manner, and is combined to form a stator coil.

3. The wet direct drive rotary servo valve according to claim 2, characterized in that: The servo drive mechanism (4) further comprises a control panel cover (5), wherein the control panel cover (5) is fixed to a side of the servo drive mechanism housing (2) opposite to the valve body (1). The servo drive mechanism (4) further comprises a magnetic encoder (43), a sealing cover (44) and a PCBA (45). The magnetic encoder (43) is arranged at an end of the rotor part (32). The sealing cover (44) is fixed to an end of the servo drive mechanism housing (2) to form a seal between the servo drive mechanism housing (2) and the control panel cover (5). The PCBA (45) is arranged in the control panel cover (5). An electrical plug (51) is arranged on the control panel cover (5), and the electrical plug (51) is electrically connected to the PCBA (45).

4. The wet direct drive rotary servo valve according to claim 1, characterized in that: The rotor part (32) comprises a rotor core shaft (321), a magnet mounting column (322) and a permanent magnet (323); the rotor core shaft (321) is connected to the valve core part (31); the magnet mounting column (322) is fixed on the rotor core shaft (321); a plurality of magnet mounting holes are provided on the magnet mounting column (322); the plurality of magnet mounting holes are axially arranged on the outer periphery of the magnet mounting column (322) and are evenly arranged in the circumferential direction of the magnet mounting column (322); and the permanent magnet (323) is fixed in the magnet mounting hole.

5. The wet direct drive rotary servo valve according to claim 1, characterized in that: A connecting oil groove is provided on the outer peripheral surface of the valve core portion (31), and the bottom surface of the connecting oil groove is formed by a combination of different planes and / or curved surfaces. When the valve core portion (31) is in different rotational states, the connecting oil groove can form different communication states with different valve body cavities, thereby forming different valve position functions.

6. The wet direct drive rotary servo valve according to claim 5, characterized in that: It also comprises a valve sleeve (6), wherein the valve body (1) is provided with a main valve hole (11) in communication with the valve body cavity, the valve sleeve (6) is fixed in the main valve hole (11), the valve core portion (31) is rotatably arranged in the valve sleeve (6), and the side wall of the valve sleeve (6) is provided with a plurality of valve sleeve holes respectively communicating with different valve body cavities and different connecting oil grooves.

7. The wet direct drive rotary servo valve according to claim 6, characterized in that: A valve sleeve hole (21) is provided at the connection end between the servo drive mechanism housing (2) and the valve body (1), one end of the valve sleeve (6) is fixed in the valve sleeve hole (21), and a drainage groove (601) connecting the valve body cavity and the drive cavity is provided on the outer peripheral surface of the valve sleeve (6).

8. The wet direct drive rotary servo valve according to claim 6, characterized in that: The hydraulic oil ports on the valve body (1) include a P port (101), a T port (102), an A port (103) and a B port (104); the valve body cavity includes a P cavity (12), a T cavity (13), an A cavity (14) and a B cavity (15); the P cavity (12), the T cavity (13), the A cavity (14) and the B cavity (15) are respectively connected to the P port (101), the T port (102), the A port (103) and the B port (104); the valve sleeve hole includes a valve sleeve P hole (61), a valve sleeve T hole (62), a valve sleeve A hole (63) and a valve sleeve B hole (64); the valve sleeve P hole (61), the valve sleeve T hole (62), the valve sleeve A hole (63) and the valve sleeve B hole (64) are respectively connected to the P cavity (12), the T cavity (13), the A cavity (14) and the B cavity (15).

9. The wet direct drive rotary servo valve according to claim 8, characterized in that: The valve sleeve P hole (61) includes a valve sleeve P1 hole (611), a valve sleeve P2 hole (612), a valve sleeve P3 hole (613) and a valve sleeve P4 hole (614); the valve sleeve T hole (62) includes a valve sleeve T1 hole (621), a valve sleeve T2 hole (622), a valve sleeve T3 hole (623) and a valve sleeve T4 hole (624); the valve sleeve A hole (63) includes a valve sleeve A1 hole (631) and a valve sleeve A2 hole (632); the valve sleeve B hole (64) includes a valve sleeve B1 hole (641) and a valve sleeve B2 hole (642); the valve sleeve P1 hole The valve sleeve (611), the valve sleeve T1 hole (621), the valve sleeve A1 hole (631), the valve sleeve P2 hole (612), the valve sleeve T2 hole (622) and the valve sleeve A2 hole (632) are sequentially arranged at the same axial position of the valve sleeve (6); the valve sleeve T3 hole (623), the valve sleeve P3 hole (613), the valve sleeve B1 hole (641), the valve sleeve T4 hole (624), the valve sleeve P4 hole (614) and the valve sleeve B2 hole (642) are sequentially arranged at another axial position of the valve sleeve (6); the connecting oil on the valve core portion (31) The grooves include a first connecting oil groove (311), a second connecting oil groove (312), a third connecting oil groove (313) and a fourth connecting oil groove (314); the first connecting oil groove (311) and the second connecting oil groove (312) are arranged opposite to each other on the outer peripheral surface of the valve core portion (31) and are connected via a first oil groove connecting hole (315); the third connecting oil groove (313) and the fourth connecting oil groove (314) are arranged opposite to each other on the outer peripheral surface of the valve core portion (31) and are connected via a second oil groove connecting hole (316); the first connecting oil groove The first connecting oil groove (311) and the second connecting oil groove (312) are arranged correspondingly to the valve sleeve P1 hole (611), the valve sleeve T1 hole (621), the valve sleeve A1 hole (631), the valve sleeve P2 hole (612), the valve sleeve T2 hole (622) and the valve sleeve A2 hole (632); the third connecting oil groove (313) and the fourth connecting oil groove (314) are arranged correspondingly to the valve sleeve T3 hole (623), the valve sleeve P3 hole (613), the valve sleeve B1 hole (641), the valve sleeve T4 hole (624), the valve sleeve P4 hole (614) and the valve sleeve B2 hole (642).

10. The wet direct drive rotary servo valve according to claim 6, characterized in that: A steel ball mounting seat (317) is provided at the end of the valve core portion (31), a steel ball is provided in the steel ball mounting seat (317), and is supported at the bottom of the main valve hole (11) by the steel ball.

11. The wet direct drive rotary servo valve according to any one of claims 1 to 10, characterized in that: A first bearing mounting portion (318) is provided at the end position of the valve core portion (31), a second bearing mounting portion (324) is provided at the connection between the valve core portion (31) and the rotor portion (32), a third bearing mounting portion (325) is provided at the end position of the rotor portion (32), and bearings (33) are provided between the first bearing mounting portion (318) and the valve body (1), between the second bearing mounting portion (324) and the servo drive mechanism housing (2), and between the third bearing mounting portion (325) and the servo drive mechanism housing (2).

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