Rotary servo valve

Abstract

Disclosed is a rotary servo valve, comprising a housing (1) and a valve body (12). The valve body (12) is fixedly mounted in the housing (1), a rotor valve element (13) is arranged in the valve body (12), a valve sleeve (10) is arranged on the rotor valve element (13), and first O-rings (11) are arranged at the lower end of the valve body (12); an end cover (3) is provided at the upper end of the housing (1), a PCBA circuit board (5) is provided in the end cover (3), and a plug (4) is provided at the upper end of the end cover (3); a first bearing (9) is provided on the upper right side of the valve body (12), and a permanent magnet is provided at the upper end of the first bearing (9). The position of a motor is controlled by means of a sensor, and the motor is controlled by using the servo technology. According to the rotary valve, the valve element is driven by the motor to rotate in a limited angle to control the flow direction and the flow velocity of a fluid. The valve body, valve sleeve and valve element use generative design and additive manufacturing, so that the fluid performance can be effectively improved, the space is effectively utilized, the waste material is reduced, and the machining amount and the number of parts are reduced, achieving the effect of reducing the manufacturing costs.

Description

A rotary servo valve Technical Field

[0001] The present invention relates to a servo valve, in particular to a rotary servo valve. Background Art

[0002] The electro-hydraulic servo valve is the heart of the electro-hydraulic servo system. Featuring high precision and fast response, it is widely used in high-precision mechatronic systems, the aerospace field, and large-scale test equipment. However, existing servo valves are heavy, bulky, and their power needs to be improved. Therefore, those skilled in the art have proposed a rotary servo valve to address the issues raised in the background art. Summary of the Invention

[0003] The object of the present invention is to provide a rotary servo valve to solve the problems raised in the above background technology.

[0004] To achieve the above object, the present invention provides the following technical solutions:

[0005] A rotary servo valve comprises a casing, the casing and a valve body, the valve body being mounted and fixed inside the casing, a rotor valve core being provided inside the valve body, a valve sleeve being provided on the rotor valve core, and an O-ring 1 being provided at the lower end of the valve body; an end cover being provided at the upper end of the casing, a PCBA circuit board being provided inside the end cover, and a plug being provided at the upper end of the end cover; a bearing 1 being provided at the upper right side of the valve body, a permanent magnet being provided at the upper end of the bearing 1, an O-ring 2 being provided at the left side of the bearing 1, an electronic stator being provided at the upper left side of the O-ring 2, a bearing 2 being provided at the upper side of the permanent magnet, and a magnetic spool being provided at the left side of the bearing 2.

[0006] As a further solution of the present invention: a bearing mounting hole is provided inside the valve sleeve, two symmetrical limit grooves are provided on both sides of the upper side of the bearing mounting hole, an O-ring mounting groove is provided on the upper side of the outer side of the valve sleeve, a sharp-edge sealing line is provided on the lower side of the valve sleeve, and a vulcanized rubber groove that is connected horizontally and vertically is provided on the lower surface of the valve sleeve.

[0007] As a further solution of the present invention: a permanent magnet mounting column is provided at the upper end of the rotor valve core, a bearing mounting column is provided at the upper end of the permanent magnet mounting column, a magnetic wick mounting hole is provided on the lower side of the bearing mounting column, the magnetic wick is installed in the magnetic wick mounting hole, two limiting structures are provided at the middle position of the outer side of the rotor valve core, the two limiting structures are arranged into a centrally symmetrical structure, and a valve core sharp edge sealing line is provided on the lower side of the rotor valve core.

[0008] As a further solution of the present invention: there are two rounds of kidney-shaped holes on the inner and outer circles of the valve sleeve distributed in an annular shape, the kidney-shaped holes in the first round along the counterclockwise direction are P5, A3, T5, P6, A4, T6 in sequence, and the kidney-shaped holes in the second round along the counterclockwise direction are T7, B3, P7, T8, B4, P8 in sequence, among which Pn is tightly fitted and connected with the corresponding Pn-4 of the valve body, An is tightly fitted and connected with the corresponding An-2 of the valve body, Bn is tightly fitted and connected with the corresponding Bn-2 of the valve body, and Tn is tightly fitted and connected with the corresponding Tn-4 of the valve body, and the kidney-shaped holes on the inner cylindrical surface are symmetrically distributed; among which, in the kidney-shaped holes in the first round along the counterclockwise direction, P5 and P6 are a pair of small holes, A3 and A4, T5 and T6 are two pairs of large holes; in the kidney-shaped holes in the second round along the counterclockwise direction, P7 and P8 are a pair of small holes, B3 and B4, T7 and T8 are two pairs of large holes.

[0009] Compared with the prior art, the present invention has the following beneficial effects:

[0010] The valve body, valve sleeve, rotor, and valve core of this invention utilize a generative AI design, ensuring uniform wall thickness in the flow channel and eliminating process holes. This significantly reduces raw materials, resulting in lightweight, compact, and high power density. The 3D-printed flow channel undergoes a grinding process, resulting in a smooth, continuous flow path with minimal pressure loss, energy savings, and high flow capacity. Compared to conventional servo valves of the same specifications, this valve can increase its rated flow rate by 1-2 times.

[0011] 2. The valve body, valve sleeve, rotor, and valve core of this invention are all 3D-printed. During the printing process, only minimal machining allowance is retained on the machined surfaces, significantly reducing the machining workload by over 80%, significantly lowering production costs. The servo motor used in this invention controls the rotation of the valve core, resulting in a fast response speed and high frequency response, reaching 300 Hz, far exceeding that of traditional servo valves.

[0012] 3. The rotor valve core of the present invention is equipped with a high-precision angular displacement sensor, which can provide real-time feedback on the angular displacement of the rotor valve core. The circuit board is equipped with a closed-loop control system for the displacement of the rotor valve core, which can very accurately control the opening of the rotor valve core, so the control accuracy is high; the rotor valve core valve sleeve of the present invention is printed with ZrO2 ceramic material, and the hardness can reach 85HRC after firing. Even if there are particulate contaminants in the oil, the hardness of the rotor valve core valve sleeve is far greater than that of the particulate contaminants in the oil, and the particulate contaminants will not cause damage to the rotor valve core valve sleeve, so this valve has a long service life, strong anti-pollution ability and high reliability.

[0013] 4. The rotor valve core and valve sleeve of the present invention do not contact each other, and the rotor valve core and valve sleeve are not worn during the rotation of the rotor valve core. The rotor valve core and valve sleeve of the traditional servo valve will definitely contact each other, so they will wear out after being used for a period of time, resulting in a short life and low reliability of the traditional servo valve. Therefore, the service life and reliability of this valve far exceed those of the traditional servo valve; the present invention adopts 3D printing technology to manufacture the rotor core. This technology can minimize the material while ensuring mechanical strength, making the motor rotor lighter and having a smaller inertia, so that the motor and valve have a faster response speed.

[0014] 5. The motor's permanent magnets utilize a magnetic ring structure, eliminating the risk of falling out. Furthermore, the pole spacing is reduced, improving the motor's cogging torque and enhancing the motor and valve precision. The housing and rotor base are designed as a single component (the housing), eliminating the risk of oil leakage from the rotor end to the stator end. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] FIG1 is a schematic structural diagram of a rotary servo valve.

[0016] FIG2 is a schematic cross-sectional view of a rotary servo valve in the AA direction.

[0017] FIG3 is a schematic structural diagram of a valve body in a rotary servo valve.

[0018] FIG4 is a schematic cross-sectional view of a valve body in a rotary servo valve in the EE direction.

[0019] FIG5 is a schematic cross-sectional view of a valve body in a rotary servo valve in the BB direction.

[0020] FIG6 is a schematic structural diagram of a valve sleeve in a rotary servo valve.

[0021] FIG7 is a schematic cross-sectional view of a valve sleeve in a rotary servo valve.

[0022] FIG8 is a top view of a valve sleeve in a rotary servo valve.

[0023] FIG9 is a schematic cross-sectional view of a valve sleeve in a rotary servo valve in the BB direction.

[0024] FIG10 is a schematic cross-sectional view of a valve sleeve in a rotary servo valve in the DD direction.

[0025] FIG11 is a schematic structural diagram of a rotor valve core in a rotary servo valve.

[0026] FIG12 is a schematic cross-sectional view of a rotor valve core in a rotary servo valve.

[0027] FIG13 is a schematic diagram of a rotor valve core in a rotary servo valve in the DD direction and the FF direction.

[0028] FIG14 is a schematic diagram of oil flow through an oil port after the valve core rotates in a rotary servo valve.

[0029] FIG15 is a schematic structural diagram of a housing in a rotary servo valve.

[0030] FIG16 is a schematic cross-sectional view of a housing in a rotary servo valve.

[0031] FIG17 is a residual diagram of the calculation process using the SST turbulence model in this embodiment.

[0032] FIG18 is a screenshot of the flow calculation results of the optimization model of this embodiment.

[0033] In the figure: housing 1, motor stator 2, end cover 3, plug 4, PCBA circuit board 5, magnetic spool 6, bearing 2 7, permanent magnet 8, bearing 1 9, valve sleeve 10, O-ring 1 11, valve body 12, rotor spool 13, O-ring 2 14, limit groove 15, bearing mounting hole 16, O-ring mounting groove 17, valve sleeve sharp edge sealing line 18, magnetic spool mounting hole 19, bearing mounting column 20, permanent magnet mounting column 21, limit structure 22, bottom oil port 23, arc groove 24, sealing line cover 25, valve core sharp edge sealing line 26, vulcanized rubber groove 27. DETAILED DESCRIPTION

[0034] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0035] Referring to Figures 1 to 18, an embodiment of the present invention shows a rotary servo valve including a housing 1, the housing 1 and a valve body 12. The valve body 12 is fixedly mounted within the housing 1. A rotor valve core 13 is disposed within the valve body 12. A valve sleeve 10 is disposed on the rotor valve core 13. An O-ring 11 is disposed at the lower end of the valve body 12.

[0036] The upper end of the housing 1 is provided with an end cover 3, a PCBA circuit board 5 is provided inside the end cover 3, and a plug 4 is provided at the upper end of the end cover 3;

[0037] A bearing 1 9 is provided on the upper right side of the valve body 12, a permanent magnet 8 is provided on the upper end of the bearing 1 9, an O-ring 2 14 is provided on the left side of the bearing 1 9, an electronic stator 2 is provided on the upper left side of the O-ring 2 14, a bearing 2 7 is provided on the upper side of the permanent magnet 8, and a magnetic spool 6 is provided on the left side of the bearing 2 7;

[0038] The valve sleeve 10 is provided with a bearing mounting hole 16 inside, with two symmetrical limit grooves 15 on both sides of the upper side of the bearing mounting hole 16. The valve sleeve 10 is provided with an O-ring mounting groove 17 on the upper side of the outer side. The valve sleeve 10 is provided with a sharp-edge sealing line 18 on the lower side. The lower surface of the valve sleeve 10 is provided with a vulcanized rubber groove 27 that is connected horizontally and vertically.

[0039] A permanent magnet mounting column 21 is provided at the upper end of the rotor valve core 13, and a bearing mounting column 20 is provided at the upper end of the permanent magnet mounting column 21. A magnetic spool mounting hole 19 is provided on the lower side of the bearing mounting column 20, and the magnetic spool 6 is installed in the magnetic spool mounting hole 19. Two limiting structures 22 are provided in the middle position of the outer side of the rotor valve core 13, and the two limiting structures 22 are arranged into a centrally symmetrical structure. A valve core sharp edge sealing line 26 is provided on the lower side of the rotor valve core 13.

[0040] A bottom oil port 23 is provided on each of the left and right sides of the lower side of the valve body 12. The valve body 12 is 3D printed using generative design. There are four P, A, B, and T oil ports on the bottom. The P, A, B, and T oil ports are connected to the upper and lower waist-shaped holes on the valve body through 3D printed oil channels. As shown in Figures 4-5, the two waist-shaped holes on the valve body are distributed in a ring shape around the valve sleeve mounting hole. The order of the first week is P1, A1, T1, P2, A2, T2, and the order of the second week is P3, B1, T3, P4, B2, and T4, among which Pn is connected to P, An is connected to A, Bn is connected to B, and Tn is connected to T. The valve body includes a T5 port connected to the bottom, wherein the T5 port is connected to the T port.

[0041] Four O-rings 11 are respectively installed on the P, A, B, and T holes of the valve body bottom plate to play a sealing role. The valve body 12 is formed in one piece by 3D printing. The valve sleeve 10 is installed in the main hole of the valve body 12. The rotor valve core 13 and the motor rotor are printed and processed in one piece. Bearing 1 9 and bearing 2 7 are installed at both ends of the rotor valve core 13. The rotor valve core 13 and the valve sleeve 10 are clearance-matched. The motor stator 2 is installed on the casing 1, and the permanent magnet 8 is installed on the rotor valve core 13. The casing 1 is fixed to the valve body 12 by screws, and the end cover 3 is fixed to the casing 1 by screws. The PCBA circuit board 5 is fixed in the end cover 3 by screws. When the motor is energized, it drives the rotor valve core 13 to rotate, and the angle of rotation of the rotor valve core 13 is fed back through the magnetic encoder 6 to achieve precise closed-loop control.

[0042] Figures 6-10 show a schematic diagram of the structure of the valve sleeve 10, which is 3D printed using generative design. There are two rounds of waist-shaped holes on the inner and outer circles of the valve sleeve 10, distributed in an annular pattern. The waist-shaped holes in the first round along the counterclockwise direction are P5, A3, T5, P6, A4, and T6, and the waist-shaped holes in the second round along the counterclockwise direction are T7, B3, P7, T8, B4, and P8, respectively. Among them, Pn is tightly connected to the corresponding Pn-4 of the valve body, An is tightly connected to the corresponding An-2 of the valve body, Bn is tightly connected to the corresponding Bn-2 of the valve body, and Tn is tightly connected to the corresponding Tn-4 of the valve body. The waist-shaped holes on the inner cylindrical surface are symmetrically distributed. The sharp edge sealing line 18 of the valve sleeve and the sharp edge sealing line 26 of the valve core ensure a certain amount of coverage to achieve a sealing effect. The O-ring mounting groove 17 is used to install the O-ring, and the bearing mounting hole is used to install a fixed bearing. The groove surface of the vulcanized rubber groove 27 is rough.

[0043] Among the waist-shaped holes in the first circle along the counterclockwise direction, P5 and P6 are a pair of small holes, A3 and A4, T5 and T6 are two pairs of large holes; among the waist-shaped holes in the second circle along the counterclockwise direction, P7 and P8 are a pair of small holes, B3 and B4, T7 and T8 are two pairs of large holes.

[0044] Figures 11-13 illustrate the rotor valve core structure, manufactured using generative design and 3D printing. This process creates a hollow structure while maintaining the rotor's mechanical strength, minimizing the rotor valve core's weight. This results in a smaller rotor inertia and faster response. Four arcuate grooves 24 are symmetrically arranged at the upper and lower ends of the rotor valve core's cylindrical surface. These correspond to eight sharp-edged seal lines 26 on the valve core, ensuring positive overlap with the valve sleeve. A stopper structure 22 limits the rotor's rotation angle. The magnetic ring is mounted on the rotor. Made of sintered neodymium iron boron, this material possesses a high magnetic energy product, meaning that less material is required for the same magnetic output, reducing rotor weight. Furthermore, the magnetic ring structure eliminates the risk of dislodging, reduces pole spacing, improves motor cogging torque, and enhances motor and valve precision. The upper and lower bearings are mounted on the bearing mounts. The rotor valve core also features a dual, symmetrical stopper design. This not only provides a double safeguard but also ensures better dynamic balancing of the motor rotor, resulting in smoother valve operation and higher precision.

[0045] Figure 14 shows a schematic diagram of the oil flow through the oil ports after the valve core rotates. When in the middle position, the P, T, A, and B oil ports are blocked and sealed by sealing wires. After the valve core rotates counterclockwise, P and A are connected, and B and T are connected. After the valve core rotates clockwise, P and B are connected, and A and T are connected. In this way, the on-off status of P, T, A, and B can be freely controlled by the motor to drive the valve core to rotate, thereby achieving reversing and precise control.

[0046] Figures 15-16 show a schematic diagram of the motor's integrated housing. This part is molded in one piece, effectively isolating the path connecting the motor's stator and rotor, eliminating the risk of oil leakage from the rotor end to the stator end.

[0047] In the fluid area of ​​the structural simulation model of this application, hydraulic oil enters through the two lower ports, passes through the throttling area of ​​the valve core in the middle, and exits through the other two ports. Compared to the original model, the valve core structure is crescent-shaped, increasing the flow area, and the inner diameter of the pipe downstream of the valve core has been nearly doubled. These two structural optimizations reduce the model's pressure drop and increase the valve's flow rate.

[0048] The polyhedra grid method is used to divide the model. For accurate calculation, 10 boundary layers are set for all walls, the growth rate is 1.2, the number of grids is 687198, and the grid quality is 0.2. The grid quality meets the requirements.

[0049] The SST turbulence model was used for the calculation, with the inlet total pressure set to 7 MPa, the outlet to atmospheric pressure, and the wall roughness set to 6.3 μm. The residual plot of the calculation process is shown in Figure 17. It can be seen that the residual is less than 1e-3, indicating that the calculation has converged.

[0050] Analysis of calculation results: The flow calculation results of the optimized model are shown in Figure 18. The mass flow rate of the P port is 0.98 kg / s, and the volume flow rate is 65.93 liters / min, which is 74.65% higher than that of the original model; the mass flow rate of the T port is 1.08 kg / s, and the volume flow rate is 72.74 liters / min, which is 57.51% higher than that of the original model.

[0051] This study optimized the structure of the valve core and downstream pipe diameter based on the original model, established a new model, and simulated the original model and the optimized model separately while ensuring other consistency. The calculation results are summarized as follows:

[0052] 1. The original model has a mass flow rate of 0.56 kg / s and a volume flow rate of 37.75 L / min at the P port; a mass flow rate of 0.68 kg / s and a volume flow rate of 46.18 L / min at the T port.

[0053] 2. The optimized model has a mass flow rate of 0.98 kg / s and a volume flow rate of 65.93 liters / min at the P port, which are 74.65% higher than those of the original model. The optimized model has a mass flow rate of 1.08 kg / s and a volume flow rate of 72.74 liters / min at the T port, which are 57.51% higher than those of the original model.

[0054] It can be seen that the optimization effect is quite obvious, and the optimized model has been greatly improved compared with the original model.

[0055] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A rotary servo valve, comprising a housing (1) and a valve body (12), characterized in that: The valve body (12) is installed and fixed inside the casing (1), and a rotor valve core (13) is arranged inside the valve body (12), a valve sleeve (10) is arranged on the rotor valve core (13), and an O-ring (11) is arranged at the lower end of the valve body (12); An end cover (3) is arranged at the upper end of the housing (1), a PCBA circuit board (5) is arranged inside the end cover (3), and a plug (4) is arranged at the upper end of the end cover (3); A bearing 1 (9) is arranged on the upper right side of the valve body (12), a permanent magnet (8) is arranged on the upper end of the bearing 1 (9), an O-ring 2 (14) is arranged on the left side of the bearing 1 (9), an electronic stator (2) is arranged on the upper left side of the O-ring 2 (14), a bearing 2 (7) is arranged on the upper side of the permanent magnet (8), and a magnetic encoder (6) is arranged on the left side of the bearing 2 (7).

2. A rotary servo valve according to claim 1, characterized in that: A bearing mounting hole (16) is provided inside the valve sleeve (10), two symmetrical limit grooves (15) are provided on both sides of the upper side of the bearing mounting hole (16), an O-ring mounting groove (17) is provided on the upper side of the outer side of the valve sleeve (10), a sharp-edge sealing line (18) is provided on the lower side of the valve sleeve (10), and a vulcanized rubber groove (27) that is connected horizontally and vertically is provided on the lower surface of the valve sleeve (10).

3. A rotary servo valve according to claim 1, characterized in that: A permanent magnet mounting column (21) is provided at the upper end of the rotor valve core (13), a bearing mounting column (20) is provided at the upper end of the permanent magnet mounting column (21), a magnetic encoder mounting hole (19) is provided at the lower inner side of the bearing mounting column (20), and the magnetic encoder (6) is mounted in the magnetic encoder mounting hole (19).

4. A rotary servo valve according to claim 3, characterized in that: Two limiting structures (22) are arranged at the middle position of the outer side of the rotor valve core (13), and the two limiting structures (22) are arranged in a centrally symmetrical structure. A valve core sharp edge sealing line (26) is arranged at the lower side of the rotor valve core (13).

5. The rotary servo valve according to claim 1, characterized in that: The motor stator (2) is mounted on the casing (1), the permanent magnet (8) is mounted on the rotor valve core (13), the casing (1) is fixed to the valve body (12) by screws, the end cover (3) is fixed to the casing (1) by screws, and the PCBA circuit board (5) is fixed in the end cover (3) by screws.

6. A rotary servo valve according to claim 1, characterized in that: Four arc grooves (24) are symmetrically arranged at the upper and lower ends of the cylindrical surface of the rotor valve core (13).

7. The rotary servo valve according to claim 1, characterized in that: The valve sleeve (10) is made by 3D printing, and has two rounds of waist-shaped holes distributed in a ring shape on the inner circle and the outer circle of the valve sleeve (10).

8. The rotary servo valve according to claim 1, characterized in that: The rotor valve core (13) is made by 3D printing.

9. A rotary servo valve according to any one of the preceding claims, characterised in that There are two rounds of waist-shaped holes on the inner circle and the outer circle of the valve sleeve (10) distributed in an annular shape. The waist-shaped holes in the first round along the counterclockwise direction are (P5, A3, T5, P6, A4, T6) in sequence, and the waist-shaped holes in the second round along the counterclockwise direction are (T7, B3, P7, T8, B4, P8) in sequence, wherein Pn is closely connected with the valve body corresponding to Pn-4, An is closely connected with the valve body corresponding to An-2, Bn is closely connected with the valve body corresponding to Bn-2, and Tn is closely connected with the valve body corresponding to Tn-4. The waist-shaped holes on the inner cylindrical surface are distributed symmetrically. Among the waist-shaped holes in the first round along the counterclockwise direction, (P5, P6) are a pair of small holes, (A3, A4) and (T5, T6) are two pairs of large holes; among the waist-shaped holes in the second round along the counterclockwise direction, (P7, P8) are a pair of small holes, (B3, B4) and (T5, T6) are two pairs of large holes. (T7, T8) are two pairs of large holes.

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