Electro-hydraulic servo valve with rotary direct drive valve as pilot and control method of electro-hydraulic servo valve

Abstract

The invention relates to the technical field of electro-hydraulic servo valves, in particular to an electro-hydraulic servo valve with a rotary direct drive valve as a pilot and a control method thereof.The electro-hydraulic servo valve comprises a main valve and a pilot valve, the main valve comprises a first valve body and a first valve element, and the first valve body is provided with a main liquid inlet channel, a main liquid outlet channel, a first main input channel and a second main input channel; the first valve element is arranged in the first valve body in an axial moving mode, and the first main input channel and the second main input channel communicate with the two axial ends of the first valve element correspondingly. The pilot valve comprises a second valve body, a second valve element and an eccentric driver. The second valve body is connected with the first valve body and provided with a pilot liquid inlet channel, a first pilot liquid outlet channel and a second pilot liquid outlet channel. The pilot liquid inlet channel is communicated with the main liquid inlet channel, the first pilot liquid outlet channel is communicated with the first main input channel, and the second pilot liquid outlet channel is communicated with the second main input channel; the second valve element is arranged in the second valve body in an axial moving mode. The driving end of the eccentric driver is in transmission connection with the second valve element. The frequency response is high, and the anti-pollution capacity is high.

Description

Technical Field

[0001] The invention relates to the technical field of electro-hydraulic servo valves, in particular to an electro-hydraulic servo valve with a rotary direct-drive valve as a pilot and a control method thereof. Background Art

[0002] In a hydraulic system, a pilot valve is usually required for the main valve, and the pilot valve is used to open or adjust the main valve core. In the prior art, there are many structures of pilot valves, including jet tube pilot valves, nozzle baffle pilot valves, etc. Taking a multi-stage electro-hydraulic servo valve as an example, when using the above three types of pilot valves, there are generally problems of low frequency response and weak anti-pollution ability. Summary of the invention

[0003] The electro-hydraulic servo valve with a rotary direct-drive valve as a pilot and the control method thereof provided in the embodiment of the present invention at least solve the problems of low frequency response and weak anti-pollution ability of the existing pilot valve, and have high frequency response and strong anti-pollution ability.

[0004] In a first aspect, the present invention provides an electro-hydraulic servo valve with a rotary direct-drive valve as a pilot, comprising a main valve, the main valve comprising a first valve body and a first valve core, the first valve body being provided with a main liquid inlet channel, a main liquid outlet channel, a first main input channel and a second main input channel; the first valve core being axially movable and arranged in the first valve body, the first main input channel and the second main input channel being connected to the axial ends of the first valve core respectively; a pilot valve, the pilot valve comprising a second valve body, a second valve core and an eccentric driver; the second valve body being connected to the first valve body, the second valve body being provided with a pilot liquid inlet channel, a first pilot liquid outlet channel and a second pilot liquid outlet channel; the pilot The liquid inlet channel is connected to the main liquid inlet channel, the first pilot liquid outlet channel is connected to the first main input channel, and the second pilot liquid outlet channel is connected to the second main input channel; the second valve core is axially movable and arranged in the second valve body; the driving end of the eccentric driver is transmission-connected with the second valve core; wherein the driving end of the eccentric driver rotates and drives the second valve core to move, so that the pilot liquid inlet channel is connected to the corresponding pilot liquid outlet channel, so that a pressure difference is generated between the first main input channel and the second main input channel to drive the first valve core to move, and the main liquid outlet channel is connected to the main liquid inlet channel, and the main liquid outlet channel outputs the fluid of the target flow rate.

[0005] In one embodiment of the present invention, the second valve body is further provided with a first pilot control channel and a second pilot control channel which are interconnected, and along the axial direction of the second valve core, the ports of the first pilot control channel, the first pilot liquid outlet channel, the pilot liquid inlet channel, the second pilot liquid outlet channel and the second pilot control channel are sequentially arranged; the second valve core is hollow along its own axial direction, and the second valve core is sequentially spaced along its own axial direction with a first pilot shoulder, a second pilot shoulder and a third pilot shoulder, a first pilot channel is provided between the first pilot shoulder and the second pilot shoulder, and the second pilot shoulder and the third pilot channel are provided between the first pilot shoulder and the second pilot shoulder. There is a second pilot platform channel between the shoulders; wherein, when the second valve core is driven and moved by the eccentric driver, the first pilot platform channel closes the first pilot control channel, the first pilot platform channel connects the pilot liquid inlet channel and the first pilot liquid outlet channel, and the second pilot platform channel connects the second pilot liquid outlet channel and the second pilot control channel; or, the second pilot platform channel closes the second pilot control channel, the second pilot platform channel connects the pilot liquid inlet channel and the second pilot liquid outlet channel, and the first pilot platform channel connects the first pilot liquid outlet channel and the first pilot control channel.

[0006] In one embodiment of the present invention, the eccentric driver includes a driving motor, which is used to receive a driving signal and rotate a target angle along a target direction; wherein the driving signal includes the target direction and the target angle; an eccentric output shaft, one end of which is transmission-connected to the driving end of the driving motor and the other end of which is provided with a transmission ball head; a transmission ball hole corresponding to the transmission ball head is provided on the second valve core, and the transmission ball head is rotatably arranged in the transmission ball hole; an angle sensor, which is used to detect the rotation angle of the driving motor, and the rotation angle is used to control the target moving distance, and the target moving distance is the moving distance of the second valve core relative to the second valve body.

[0007] In one embodiment of the present invention, the pilot valve also includes a second valve sleeve, which is arranged in the second valve body, the second valve sleeve is hollow along its own axial direction, and the second valve core is axially movably arranged in the second valve sleeve; the second valve sleeve is provided with a pilot liquid inlet through hole, a first pilot liquid outlet through hole and a second pilot liquid outlet through hole, the pilot liquid inlet through hole is connected to the pilot liquid inlet channel, the first pilot liquid outlet through hole is connected to the first pilot liquid outlet channel, and the second pilot liquid outlet through hole is connected to the second pilot liquid outlet channel; wherein, when the second valve core is driven and moved by the eccentric driver, the second valve core makes the pilot liquid inlet through hole connected to the first pilot liquid outlet through hole; or, the second valve core makes the pilot liquid inlet through hole connected to the second pilot liquid outlet through hole.

[0008] In one embodiment of the present invention, the main valve also includes: a displacement sensor, which is used to detect the actual moving distance of the first valve core; a controller, which is electrically connected to the displacement sensor and the eccentric driver, respectively, and is used to compare the preset moving distance and the actual moving distance, and when the deviation value is non-zero, transmit a new drive signal to the eccentric driver to control the eccentric driver to drive the second valve core to move; wherein the deviation value is equal to the difference between the preset moving distance and the actual moving distance.

[0009] In one embodiment of the present invention, the main liquid outlet channel includes a first main liquid outlet channel and a second main liquid outlet channel, and the first valve body is further provided with a first main control channel and a second main control channel that are interconnected. Along the axial direction of the first valve core, ports of the first main control channel, the first main liquid outlet channel, the main liquid inlet channel, the second main liquid outlet channel and the second main control channel are sequentially arranged; the first valve core is provided with a first main shoulder, a second main shoulder, a third main shoulder and a fourth main shoulder in sequence along its own axial direction, and a first main shoulder channel is provided between the first main shoulder and the second main shoulder, a second main shoulder channel is provided between the second main shoulder and the third main shoulder, and a third main shoulder channel is provided between the third main shoulder and the fourth main shoulder; wherein, when the first valve core is driven and moved by the pressure difference, the second main shoulder channel is connected with the main liquid inlet channel and the first main liquid outlet channel, and the third main shoulder channel is connected with the second main liquid outlet channel and the second main control channel; or, the second main shoulder channel is connected with the main liquid inlet channel and the second main liquid outlet channel, and the first main shoulder channel is connected with the first main liquid outlet channel and the first main control channel.

[0010] In one embodiment of the present invention, the main valve further comprises a first valve sleeve, the first valve sleeve is arranged in the first valve body, the first valve sleeve is hollow along its own axial direction, and the first valve core is axially movably arranged in the first valve sleeve; the first valve sleeve is provided with a main liquid inlet through hole, a first main liquid outlet through hole, a second main liquid outlet through hole, a first main control through hole and a second main control through hole, the main liquid inlet through hole is connected to the main liquid inlet channel, the first main liquid outlet through hole is connected to the first main liquid outlet channel, the second main liquid outlet through hole is connected to the second main liquid outlet channel, the first main control through hole is connected to the first main control channel, and the second main control through hole is connected to the second main control channel; wherein, when the first valve core is driven and moved by the pressure difference, the main liquid inlet through hole is connected to the first main liquid outlet through hole, the second main liquid outlet through hole is connected to the second main control through hole; or, the main liquid inlet through hole is connected to the second main liquid outlet through hole, and the first main liquid outlet through hole is connected to the first main control through hole.

[0011] In one embodiment of the present invention, the first valve sleeve is provided with a plurality of the main liquid inlet through holes, a plurality of the first main liquid outlet through holes, a plurality of the second main liquid outlet through holes, a plurality of the first main control through holes and a plurality of the second main control through holes, and the plurality of the main liquid inlet through holes, the plurality of the first main liquid outlet through holes, the plurality of the second main liquid outlet through holes, the plurality of the first main control through holes and the plurality of the second main control through holes are uniformly distributed along the circumference of the first valve sleeve.

[0012] In a second aspect, the present invention further provides a control method for an electro-hydraulic servo valve with a rotary direct-drive valve as a pilot based on any one of the above-mentioned items, comprising: receiving fluid through a main liquid inlet channel of a first valve body; wherein a main liquid outlet channel, a first main input channel, and a second main input channel are also provided on the first valve body; a first valve core is axially movably arranged in the first valve body, and the first main input channel and the second main input channel are respectively connected to the axial ends of the first valve core; a driving signal is received through an eccentric driver; wherein a driving end of the eccentric driver is transmission-connected to a second valve core, and the second valve core is axially movably arranged in the second valve body, and the second valve body is connected to the first valve body, and a A pilot liquid inlet channel, a first pilot liquid outlet channel and a second pilot liquid outlet channel are provided, the pilot liquid inlet channel is connected to the main liquid inlet channel, the first pilot liquid outlet channel is connected to the first main input channel, and the second pilot liquid outlet channel is connected to the second main input channel; in response to the driving signal, the driving end of the eccentric driver rotates and drives the second valve core to move, so that the pilot liquid inlet channel is connected to the corresponding pilot liquid outlet channel; the fluid flows from the pilot liquid inlet channel into the corresponding pilot liquid outlet channel, so that a pressure difference is generated between the first main input channel and the second main input channel to drive the first valve core to move; the main liquid outlet channel is connected to the main liquid inlet channel to output the fluid of the target flow rate.

[0013] In one embodiment of the present invention, the actual moving distance of the first valve core is detected; the preset moving distance and the actual moving distance are compared; and when the deviation value is non-zero, a new drive signal is emitted to the eccentric driver to control the eccentric driver to drive the second valve core to move; wherein the deviation value is equal to the difference between the preset moving distance and the actual moving distance.

[0014] The above technical solution of the present invention has the following beneficial effects compared with the prior art:

[0015] The electro-hydraulic servo valve with a rotary direct-drive valve as a pilot described in the present invention can effectively improve the performance of the valve body by providing a pilot valve for the main valve that is driven by an eccentric driver to move the second valve core. Compared with the multi-stage electro-hydraulic servo valve with a nozzle baffle structure as a pilot, the present invention has stronger anti-pollution ability and higher frequency response; compared with the multi-stage electro-hydraulic servo valve with a jet tube structure as a pilot, the present invention not only has stronger anti-pollution ability and higher frequency response, but also has low energy consumption; compared with the multi-stage electro-hydraulic servo valve with a cylindrical slide valve driven by a proportional solenoid or a force motor as a pilot, the present invention has a higher frequency response, a smaller size, and higher precision. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art descriptions. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other embodiments can be obtained based on these drawings without creative work. In the drawings:

[0017] Figure 1 It is a schematic structural diagram of an electro-hydraulic servo valve with a rotary direct-drive valve as a pilot in a preferred embodiment of the present invention.

[0018] Figure 2 It is one of the cross-sectional structural schematic diagrams of an electro-hydraulic servo valve with a rotary direct-drive valve as a pilot in a preferred embodiment of the present invention.

[0019] Figure 3 This is the second schematic cross-sectional structure diagram of the electro-hydraulic servo valve with a rotary direct-drive valve as a pilot in the preferred embodiment of the present invention.

[0020] Figure 4 It is a schematic cross-sectional view of the pilot valve in a preferred embodiment of the present invention.

[0021] Figure 5 It is a schematic cross-sectional structural diagram of the main valve in a preferred embodiment of the present invention.

[0022] Figure 6 It is a flow chart of a control method of an electro-hydraulic servo valve with a rotary direct-drive valve as a pilot in a preferred embodiment of the present invention.

[0023] The above drawings include the following reference numerals:

[0024] 10. Main valve; 11. First valve body; 111. Main inlet channel; 1111. Pilot channel; 112. Main outlet channel; 1121. First main outlet channel; 1122. Second main outlet channel; 113. First main input channel; 114. Second main input channel; 115. First main control channel; 116. Second main control channel; 12. First valve core; 121. First main shoulder; 122. Second main shoulder; 123. First main input channel; 114. Second main input channel; 115. First main control channel; 116. Second main control channel; 12. First valve core; 121. First main shoulder; 122. Second main shoulder; 123. 3rd main shoulder; 124, 4th main shoulder; 125, 1st main channel; 126, 2nd main channel; 127, 3rd main channel; 13, displacement sensor; 14, controller; 15, 1st valve sleeve; 151, main liquid inlet hole; 152, 1st main liquid outlet hole; 153, 2nd main liquid outlet hole; 154, 1st main control hole; 155, 2nd main control hole; 20, pilot valve; 21, 2nd valve body; 211, pilot inlet hole Liquid channel; 2111, first pilot liquid inlet channel; 2112, second pilot liquid inlet channel; 212, first pilot liquid outlet channel; 213, second pilot liquid outlet channel; 214, first pilot control channel; 215, second pilot control channel; 22, second valve core; 221, first pilot shoulder; 222, second pilot shoulder; 223, third pilot shoulder; 224, first pilot stage channel; 225, second pilot stage channel; 22 6. Transmission ball hole; 23. Eccentric driver; 231. Drive motor; 232. Eccentric output shaft; 2321. Transmission ball head; 233. Angle sensor; 24. Second valve sleeve; 2411. First pilot liquid inlet hole; 2412. Second pilot liquid inlet hole; 242. First pilot liquid outlet hole; 243. Second pilot liquid outlet hole; 244. First pilot control hole; 245. Second pilot control hole; 246. Transmission channel. DETAILED DESCRIPTION

[0025] Embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although certain embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as being limited to the embodiments described herein, which are instead provided for a more thorough and complete understanding of the present invention. It should be understood that the drawings and embodiments of the present invention are only for exemplary purposes and are not intended to limit the scope of protection of the present invention.

[0026] In multi-stage electro-hydraulic servo valves, when using a jet tube pilot valve, the jet tube has a large swing inertia and a low frequency response; the continuous high-speed jet causes a large energy consumption of the valve, and the valve has a relatively weak anti-pollution ability. When using a nozzle flapper pilot valve, the valve is prone to jamming and has a relatively weak anti-pollution ability. In addition, there are also cylindrical slide valve pilot valves driven by proportional solenoids or force motors. Although they have relatively improved anti-pollution ability, they are large in size and have a low frequency response.

[0027] To solve the above problems, refer to Figure 1 and Figure 2 As shown, the present invention provides an electro-hydraulic servo valve with a rotary direct-drive valve as a pilot, comprising a main valve 10 and a pilot valve 20 .

[0028] The main valve 10 includes a first valve body 11 and a first valve core 12. The first valve core 12 is axially movable and arranged in the first valve body 11 to cooperate with the pilot valve 20 to realize the on-off of the oil circuit and the control of the flow rate. Those skilled in the art can configure the corresponding sealing structure according to actual needs, such as setting a sealing ring to ensure the sealing of the valve, which will not be repeated.

[0029] The first valve body 11 is provided with a main liquid inlet channel 111, a main liquid outlet channel 112, a first main input channel 113 and a second main input channel 114. The main liquid inlet channel 111 serves as a flow pressure inlet of the first valve body 11, and the main liquid outlet channel 112 serves as a flow pressure outlet of the first valve body 11. Those skilled in the art can set the main liquid outlet channel 112 according to actual needs. For example, the main liquid outlet channel 112 includes a first main liquid outlet channel 1121 and a second main liquid outlet channel 1122 that are independent of each other.

[0030] The first main input channel 113 and the second main input channel 114 are respectively connected to the two axial ends of the first valve core 12; the two channels are simultaneously connected to the pilot valve 20 to transmit hydraulic pressure, thereby causing the first valve core 12 to move axially.

[0031] Those skilled in the art can also provide other channels on the first valve body 11 or connect the first valve body 11 with other power controllers 14 according to actual needs.

[0032] The pilot valve 20 includes a second valve body 21, a second valve core 22 and an eccentric driver 23. The second valve body 21 is connected to the first valve body 11, and the two are fixedly connected by bolts. The second valve body 21 is provided with a pilot liquid inlet channel 211, a first pilot liquid outlet channel 212 and a second pilot liquid outlet channel 213.

[0033] The pilot inlet channel 211 is connected to the main inlet channel 111 so as to receive the fluid, such as hydraulic oil, in the main inlet channel 111 . Exemplarily, a pilot channel 1111 is provided on the main inlet channel 111 to achieve communication with the pilot inlet channel 211 .

[0034] The first pilot outlet fluid channel 212 is connected to the first main input channel 113, and the second pilot outlet fluid channel 213 is connected to the second main input channel 114 to transmit hydraulic pressure under corresponding conditions. The second valve core 22 is axially movable in the second valve body 21, and the driving end of the eccentric driver 23 is drivingly connected to the second valve core 22.

[0035] Those skilled in the art can also set other channels on the second valve body 21 according to actual needs. For example, the second valve body 21 is set to a three-position four-way valve structure.

[0036] In actual use, the eccentric driver 23 receives a driving signal, causing its driving end to rotate, thereby driving the second valve core 22 to move axially relative to the second valve body 21. After the second valve core 22 moves, the pilot inlet channel 211 and the corresponding pilot outlet channel that were originally isolated will be connected. At this time, the hydraulic oil flows from the pilot inlet channel 211 into the second valve body 21 and into the corresponding pilot outlet channel, and then flows into the main input channel of the first valve body 11.

[0037] At this time, due to the influence of the hydraulic pressure, a pressure difference is generated between the first main input channel 113 and the second main input channel 114. Accordingly, under the action of the pressure difference, the first valve core 12 is driven to move axially relative to the first valve body 11. After the first valve core 12 moves, the main liquid outlet channel 112 is connected to the main liquid inlet channel 111, and then the main liquid outlet channel 112 can output the target flow rate of the fluid. Among them, the flow rate of the output fluid has a certain proportional relationship with the drive signal received by the eccentric driver 23.

[0038] The electro-hydraulic servo valve with a rotary direct-drive valve as a pilot according to the present invention can effectively improve the valve body performance by providing a pilot valve 20 driven by an eccentric driver 23 for the main valve 10 to move the second valve core 22. Compared with the multi-stage electro-hydraulic servo valve with a nozzle baffle structure as a pilot, the present invention has stronger anti-pollution ability and higher frequency response; compared with the multi-stage electro-hydraulic servo valve with a jet tube structure as a pilot, the present invention not only has stronger anti-pollution ability and higher frequency response, but also has low energy consumption; compared with the multi-stage electro-hydraulic servo valve with a cylindrical slide valve driven by a proportional solenoid or a force motor as a pilot, the present invention has higher frequency response, smaller size and higher precision.

[0039] Reference Figure 3 and Figure 4 As shown, in the electro-hydraulic servo valve with a rotary direct-drive valve as a pilot described in the present invention, in some embodiments, a first pilot control channel 214 and a second pilot control channel 215 are further provided on the second valve body 21, and the first pilot control channel 214 and the second pilot control channel 215 are interconnected.

[0040] Preferably, the pilot liquid inlet channel 211 includes a first pilot liquid inlet channel 2111 and a second pilot liquid inlet channel 2112 , and the liquid inlet ports of the first pilot liquid inlet channel 2111 and the second pilot liquid inlet channel 2112 are both connected to the pilot channel 1111 to receive the hydraulic oil of the main liquid inlet channel 111 .

[0041] Along the axial direction of the second valve core 22, the ports of the first pilot control channel 214, the first pilot liquid outlet channel 212, the first pilot liquid inlet channel 2111, the second pilot liquid inlet channel 2112, the second pilot liquid outlet channel 213 and the second pilot control channel 215 are arranged in sequence to cooperate with the second valve core 22 to realize the on-off control and flow rate control of the pilot flow path.

[0042] Correspondingly, the second valve core 22 is provided with a first pilot shoulder 221, a second pilot shoulder 222 and a third pilot shoulder 223 in sequence along its axial direction, a first pilot land channel 224 is provided between the first pilot shoulder 221 and the second pilot shoulder 222, and a second pilot land channel 225 is provided between the second pilot shoulder 222 and the third pilot shoulder 223. It can be understood that each pilot land channel is enclosed by a corresponding pilot shoulder and the inner wall of the valve body or the inner wall of the valve sleeve.

[0043] Preferably, the second valve core 22 is hollow along its own axial direction, which can effectively reduce the fluid flow resistance, achieve uniform flow distribution, reduce the valve core mass, and improve the valve core flexibility, adaptability, reliability and stability.

[0044] The pilot valve 20 of this structure is a three-position four-way valve structure, which has a simple structure, strong adaptability, strong anti-pollution ability, and is easy to maintain. In actual use, the pilot valve 20 includes a cutoff state and two connected states when the second valve core 22 is driven and moved by the eccentric driver 23.

[0045] When the pilot valve 20 is in the shutoff state, the pilot fluid inlet passage 211 is closed by the second pilot shoulder 222 , and is shut off from the two pilot fluid outlet passages.

[0046] When the pilot valve 20 is in one of the connected states, the first pilot shoulder 221 closes the first pilot control channel 214, the first pilot stage channel 224 connects the first pilot inlet channel 2111 and the first pilot outlet channel 212, and the second pilot stage channel 225 connects the second pilot outlet channel 213 and the second pilot control channel 215. Due to the influence of the hydraulic pressure, a pressure difference is generated between the first main input channel 113 and the second main input channel 114, the first valve core 12 moves under the action of the pressure difference, the main outlet channel 112 is connected to the main inlet channel 111, and then the main outlet channel 112 can output the fluid of the target flow rate.

[0047] When the pilot valve 20 is in another connected state, the second pilot shoulder 222 closes the second pilot control channel 215, the second pilot stage channel 225 connects the second pilot inlet channel 2112 and the second pilot outlet channel 213, and the first pilot stage channel 224 connects the first pilot outlet channel 212 and the first pilot control channel 214. Due to the influence of the hydraulic pressure, a pressure difference is generated between the first main input channel 113 and the second main input channel 114, and the first valve core 12 moves under the action of the pressure difference, the main outlet channel 112 is connected to the main inlet channel 111, and then the main outlet channel 112 can output the fluid of the target flow rate.

[0048] Reference Figure 4 As shown, in the electro-hydraulic servo valve with a rotary direct-drive valve as a pilot according to the present invention, in some embodiments, the eccentric driver 23 includes a drive motor 231 , an eccentric output shaft 232 and an angle sensor 233 .

[0049] The drive motor 231 is used to receive a drive signal. Specifically, the drive motor 231 includes a motor stator and a motor rotor. After receiving the drive signal, the motor stator and the motor rotor cooperate to rotate the motor rotor in a target direction and at a target angle. The drive signal includes the target direction and target angle that the motor rotor is to rotate.

[0050] One end of the eccentric output shaft 232 is drivingly connected to the driving end of the driving motor 231, and the other end is provided with a driving ball head 2321. The second valve core 22 is provided with a driving ball hole 226 corresponding to the driving ball head 2321, and the driving ball head 2321 is rotatably arranged in the driving ball hole 226. The driving ball hole 226 and the ball hole of the driving ball head 2321 cooperate to convert the rotational motion of the driving motor 231 into the axial movement of the second valve core 22, which has a compact structure, a small size, is stable and reliable, and has a high frequency response and high precision.

[0051] The angle sensor 233 is used to detect the rotation angle of the drive motor 231, and the rotation angle is used to control the target moving distance. The target moving distance is the moving distance of the second valve core 22 relative to the second valve body 21. Depending on the rotation angle of the drive motor 231, the moving distance of the second valve core 22 will also be different. By setting the angle sensor 233, the relative position of the second valve core 22 can be controlled by controlling the rotation angle of the motor rotor, thereby effectively improving the accuracy and reliability of the valve.

[0052] Reference Figure 4As shown, in the electro-hydraulic servo valve with a rotary direct-drive valve as a pilot according to the present invention, in some embodiments, the pilot valve 20 also includes a second valve sleeve 24, and the second valve sleeve 24 is arranged in the second valve body 21. Preferably, the second valve sleeve 24 is detachably connected to the second valve body 21. The second valve sleeve 24 is hollow along its own axial direction, and the second valve core 22 is axially movable in the second valve sleeve 24. By setting the second valve sleeve 24, support and guidance can be provided for the second valve core 22, ensuring that the second valve core 22 will not deflect or get stuck during the movement, thereby ensuring the sealing of the valve and the smoothness of operation. In addition, the second valve sleeve 24 can also reduce the friction and wear caused by the direct contact between the second valve core 22 and the second valve body 21, extend the service life of both, and reduce the maintenance cost and replacement frequency. Preferably, a transmission channel 246 for setting the eccentric output shaft 232 is provided on the second valve sleeve 24.

[0053] The second valve sleeve 24 is provided with a pilot liquid inlet through hole, a first pilot liquid outlet through hole 242 and a second pilot liquid outlet through hole 243. The pilot liquid inlet through hole is connected to the pilot liquid inlet channel 211, the first pilot liquid outlet through hole 242 is connected to the first pilot liquid outlet channel 212, and the second pilot liquid outlet through hole 243 is connected to the second pilot liquid outlet channel 213. Different through holes cooperate with corresponding shoulders of the second valve core 22 to form a variable throttle structure to achieve on-off control or flow control.

[0054] In the case where the first pilot liquid inlet channel 2111 and the second pilot liquid inlet channel 2112 are provided, the pilot liquid inlet through hole includes an independent first pilot liquid inlet through hole 2411 and a second pilot liquid inlet through hole 2412. The first pilot liquid inlet through hole 2411 is connected to the first pilot liquid inlet channel 2111, and the second pilot liquid inlet through hole 2412 is connected to the second pilot liquid inlet channel 2112. In the case where the first pilot control channel 214 and the second pilot control channel 215 are provided, the second valve sleeve 24 is also provided with a first pilot control through hole 244 and a second pilot control through hole 245. The first pilot control through hole 244 is connected to the first pilot control channel 214, and the second pilot control through hole 245 is connected to the second pilot control channel 215.

[0055] When the pilot valve 20 is in the cut-off state, the first pilot liquid inlet through hole 2411 and the second pilot liquid inlet through hole 2412 are closed by the second pilot shoulder 222 , which is cut off from the two pilot liquid outlet through holes.

[0056] When the pilot valve 20 is in one of the connected states, the first pilot shoulder 221 of the second valve core 22 closes the first pilot control through hole 244, and the first pilot platform channel 224 connects the first pilot liquid inlet through hole 2411 and the first pilot liquid outlet through hole 242, thereby connecting the first pilot liquid inlet channel 2111 and the first pilot liquid outlet channel 212. At the same time, the second pilot platform channel 225 connects the second pilot liquid outlet through hole 243 and the second pilot control through hole 245.

[0057] When the pilot valve 20 is in another connected state, the second pilot shoulder 222 of the second valve core 22 closes the second pilot control through hole 245, and the second pilot platform channel 225 connects the second pilot liquid inlet through hole 2412 and the second pilot liquid outlet through hole 243, thereby connecting the second pilot liquid inlet channel 2112 and the second pilot liquid outlet channel 213. At the same time, the first pilot platform channel 224 connects the first pilot liquid outlet through hole 242 and the first pilot control through hole 244.

[0058] Reference Figure 3 and Figure 5 As shown, in the electro-hydraulic servo valve with a rotary direct-drive valve as a pilot according to the present invention, in some embodiments, the main valve 10 further includes a displacement sensor 13 and a controller 14 .

[0059] The displacement sensor 13 is used to detect the actual movement distance of the first valve core 12. Preferably, the displacement sensor 13 is coaxially connected to the first valve core 12.

[0060] The controller 14 is electrically connected to the displacement sensor 13 and the eccentric driver 23 respectively; exemplary, the connection is achieved through cables. Preferably, an electrical box is provided outside the controller 14, and the electrical box is connected to the first valve body 11 through bolts.

[0061] The controller 14 is used to compare the preset moving distance with the actual moving distance, and when the deviation value is non-zero, transmit a new driving signal to the eccentric driver 23 to control the eccentric driver 23 to drive the second valve core 22 to move; wherein the deviation value is equal to the difference between the preset moving distance and the actual moving distance. The new driving signal is related to the deviation value; preferably, when the deviation value is non-zero, the deviation value is repeatedly adjusted until the deviation value returns to zero. By setting this structure, it can effectively ensure that the main liquid outlet channel 112 outputs a fluid with an accurate flow rate, thereby improving the accuracy of the valve.

[0062] Reference Figure 5 As shown, in the electro-hydraulic servo valve with a rotary direct-drive valve as a pilot described in the present invention, in some embodiments, the main liquid outlet channel 112 includes a first main liquid outlet channel 1121 and a second main liquid outlet channel 1122, which has stronger adaptability.

[0063] The first valve body 11 is also provided with a first main control channel 115 and a second main control channel 116 which are interconnected; along the axial direction of the first valve core 12, ports of the first main control channel 115, the first main liquid outlet channel 1121, the main liquid inlet channel 111, the second main liquid outlet channel 1122 and the second main control channel 116 are arranged in sequence to cooperate with the first valve core 12 to realize on-off control of the flow path and flow rate control.

[0064] Correspondingly, the first valve core 12 is provided with a first main shoulder 121, a second main shoulder 122, a third main shoulder 123 and a fourth main shoulder 124 in sequence along its own axial direction, a first main shoulder channel 125 is provided between the first main shoulder 121 and the second main shoulder 122, a second main shoulder channel 126 is provided between the second main shoulder 122 and the third main shoulder 123, and a third main shoulder channel 127 is provided between the third main shoulder 123 and the fourth main shoulder 124. It can be understood that each main shoulder channel is enclosed by each main shoulder and the inner wall of the valve body or the inner wall of the valve sleeve.

[0065] In actual use, the main valve 10 includes a blocking state and two connecting states when the first valve core 12 is driven and moved by the pressure difference.

[0066] When the main valve 10 is in the cut-off state, the first main liquid outlet channel 1121 is closed by the second main shoulder 122 , and the second main liquid outlet channel 1122 is closed by the third main shoulder 123 , and both channels are cut off from the main liquid inlet channel 111 .

[0067] When the main valve 10 is in one of the connected states, the third main stage channel 127 connects the second main liquid outlet channel 1122 and the second main control channel 116, and the second main stage channel 126 connects the main liquid inlet channel 111 and the first main liquid outlet channel 1121, so that the first main liquid outlet channel 1121 can output fluid of the target flow rate.

[0068] When the main valve 10 is in another connected state, the first main stage channel 125 connects the first main liquid outlet channel 1121 and the first main control channel 115, and the second main stage channel 126 connects the main liquid inlet channel 111 and the second main liquid outlet channel 1122, so that the second main liquid outlet channel 1122 can output fluid of the target flow rate.

[0069] Further, see Figure 5As shown, in the electro-hydraulic servo valve with a rotary direct-drive valve as a pilot described in the present invention, in some embodiments, the main valve 10 also includes a first valve sleeve 15, and the first valve sleeve 15 is arranged in the first valve body 11. The first valve sleeve 15 is hollow along its own axial direction, and the first valve core 12 is axially movable in the first valve sleeve 15. By providing the first valve sleeve 15, support and guidance can be provided for the first valve core 12, ensuring that the first valve core 12 will not deflect or get stuck during the movement, thereby ensuring the sealing of the valve and the smoothness of operation. In addition, the first valve sleeve 15 can also reduce the friction and wear caused by the direct contact between the first valve core 12 and the first valve body 11, extend the service life of both, and reduce maintenance costs and replacement frequency.

[0070] The first valve sleeve 15 is provided with a main liquid inlet through hole 151, a first main liquid outlet through hole 152, a second main liquid outlet through hole 153, a first main control through hole 154 and a second main control through hole 155. The main liquid inlet through hole 151 is connected to the main liquid inlet channel 111, the first main liquid outlet through hole 152 is connected to the first main liquid outlet channel 1121, the second main liquid outlet through hole 153 is connected to the second main liquid outlet channel 1122, the first main control through hole 154 is connected to the first main control channel 115, and the second main control through hole 155 is connected to the second main control channel 116. Different through holes cooperate with corresponding shoulders of the first valve core 12 to form a variable throttle structure to achieve on-off control or flow control.

[0071] When the main valve 10 is in the shutoff state, the first main liquid outlet through hole 152 is closed by the second main shoulder 122 , and the second main liquid outlet through hole 153 is closed by the third main shoulder 123 . Both through holes are shut off from the main liquid inlet through hole 151 .

[0072] When the main valve 10 is in one of the connected states, the third main stage channel 127 is connected to the second main liquid outlet hole 153 and the second main control hole 155, and the second main stage channel 126 is connected to the main liquid inlet hole 151 and the first main liquid outlet hole 152, thereby making the main liquid inlet channel 111 and the first main liquid outlet channel 1121 connected, and the first main liquid outlet channel 1121 can output fluid of the target flow rate.

[0073] When the main valve 10 is in another connected state, the first main stage channel 125 connects the first main liquid outlet hole 152 and the first main control hole 154, and the second main stage channel 126 connects the main liquid inlet hole 151 and the second main liquid outlet hole 153, so that the main liquid inlet channel 111 and the second main liquid outlet channel 1122 are connected, and the second main liquid outlet channel 1122 can output fluid of the target flow rate.

[0074] Further, see Figure 5As shown, in the electro-hydraulic servo valve with a rotary direct-drive valve as a pilot described in the present invention, in some embodiments, the first valve sleeve 15 is provided with a plurality of main liquid inlet holes 151, a plurality of first main liquid outlet holes 152, a plurality of second main liquid outlet holes 153, a plurality of first main control holes 154 and a plurality of second main control holes 155, and the plurality of main liquid inlet holes 151, a plurality of first main liquid outlet holes 152, a plurality of second main liquid outlet holes 153, a plurality of first main control holes 154 and a plurality of second main control holes 155 are uniformly distributed along the circumference of the first valve sleeve 15. By setting up this structure, uniform flow diversion can be achieved, and precise regulation of flow can be achieved. In addition, the possibility of blockage is effectively reduced, which is convenient for balancing the radial force on the valve sleeve, extending the service life and improving the assembly quality.

[0075] On the other hand, referring to Figure 6 As shown, an embodiment of the present invention further provides a control method based on an electro-hydraulic servo valve with a rotary direct drive valve as a pilot as described in any of the above embodiments. The control method includes:

[0076] The fluid is received through the main liquid inlet channel 111 of the first valve body 11 .

[0077] Among them, the first valve body 11 is also provided with a main liquid outlet channel 112, a first main input channel 113 and a second main input channel 114. The main liquid outlet channel 112 serves as the flow pressure outlet of the first valve body 11. The first valve core 12 is axially movably arranged in the first valve body 11 to cooperate with the pilot valve 20 to realize the on-off of the oil circuit and the control of the flow rate. Those skilled in the art can configure the corresponding sealing structure according to actual needs, such as setting a sealing ring to ensure the sealing of the valve, which will not be repeated. The first main input channel 113 and the second main input channel 114 are respectively connected to the axial ends of the first valve core 12; the two channels are simultaneously connected to the pilot valve 20 to transmit liquid pressure, thereby causing the first valve core 12 to move axially.

[0078] The drive signal is received by the eccentric driver 23 .

[0079] Among them, the driving end of the eccentric driver 23 is transmission-connected with the second valve core 22, and the second valve core 22 is axially movable in the second valve body 21. The second valve body 21 is connected to the first valve body 11, and exemplarily, the two are fixedly connected by bolts. The second valve body 21 is provided with a pilot liquid inlet channel 211, a first pilot liquid outlet channel 212, and a second pilot liquid outlet channel 213. The pilot liquid inlet channel 211 is connected to the main liquid inlet channel 111 so as to receive the fluid, such as hydraulic oil, of the main liquid inlet channel 111; exemplarily, the main liquid inlet channel 111 is provided with a pilot channel 1111 to achieve communication with the pilot liquid inlet channel 211. The first pilot liquid outlet channel 212 is connected to the first main input channel 113, and the second pilot liquid outlet channel 213 is connected to the second main input channel 114 to transmit liquid pressure under corresponding circumstances.

[0080] In response to the driving signal, the driving end of the eccentric driver 23 rotates and drives the second valve core 22 to move, so that the pilot inlet channel 211 is connected to the corresponding pilot outlet channel. For example, the pilot inlet channel 211 is connected to the first pilot outlet channel 212, or to the second pilot outlet channel 213.

[0081] The fluid flows from the pilot fluid inlet channel 211 into the corresponding pilot fluid outlet channel, so that a pressure difference is generated between the first main input channel 113 and the second main input channel 114 to drive the first valve core 12 to move.

[0082] The main liquid outlet channel 112 is connected to the main liquid inlet channel 111 to output a target flow rate of fluid.

[0083] The control method of the present invention, in some embodiments, further includes:

[0084] The actual moving distance of the first valve element 12 is detected.

[0085] Exemplarily, the actual moving distance of the first valve core 12 is detected by providing a displacement sensor 13. Preferably, the displacement sensor 13 is coaxially connected to the first valve core 12.

[0086] The preset moving distance and the actual moving distance are compared, wherein the difference between the preset moving distance and the actual moving distance is the deviation value.

[0087] When the deviation value is non-zero, a new driving signal is sent to the eccentric driver 23 to control the eccentric driver 23 to drive the second valve core 22 to move. The new driving signal is related to the deviation value; preferably, when the deviation value is non-zero, the adjustment is repeated until the deviation value returns to zero, thereby effectively ensuring that the main liquid outlet channel 112 outputs a fluid with an accurate flow rate, thereby improving the accuracy of the valve.

[0088] Working principle:

[0089] In actual use, the valve includes an isolation state and two connection states.

[0090] When the valve is in the cut-off state, the eccentric output shaft 232 of the eccentric driver 23 is in the initial position. At this time, the two pilot liquid inlet channels 211 are both closed by the second pilot shoulder 222 and are cut off from the two pilot liquid outlet channels; the first main liquid outlet channel 1121 is closed by the second main shoulder 122, and the second main liquid outlet channel 1122 is closed by the third main shoulder 123, and both channels are cut off from the main liquid inlet channel 111.

[0091] When the pilot valve 20 is in one of the connected states, the first pilot shoulder 221 closes the first pilot control channel 214, the first pilot stage channel 224 connects the first pilot inlet channel 2111 and the first pilot outlet channel 212, and the second pilot stage channel 225 connects the second pilot outlet channel 213 and the second pilot control channel 215. Due to the influence of the hydraulic pressure, a pressure difference is generated between the first main input channel 113 and the second main input channel 114, and the first valve core 12 moves under the action of the pressure difference. The third main stage channel 127 connects the second main outlet channel 1122 and the second main control channel 116, and the second main stage channel 126 connects the main inlet channel 111 and the first main outlet channel 1121, so that the first main outlet channel 1121 can output the fluid of the target flow rate.

[0092] When the pilot valve 20 is in another connected state, the second pilot shoulder 222 closes the second pilot control channel 215, the second pilot stage channel 225 connects the second pilot inlet channel 2112 and the second pilot outlet channel 213, and the first pilot stage channel 224 connects the first pilot outlet channel 212 and the first pilot control channel 214. Due to the influence of the hydraulic pressure, a pressure difference is generated between the first main input channel 113 and the second main input channel 114, and the first valve core 12 moves under the action of the pressure difference. The first main stage channel 125 connects the first main outlet channel 1121 and the first main control channel 115, and the second main stage channel 126 connects the main inlet channel 111 and the second main outlet channel 1122, so that the second main outlet channel 1122 can output the fluid of the target flow rate.

[0093] Before the corresponding main liquid outlet channel outputs the fluid, the displacement sensor 13 is used to detect the actual moving distance of the first valve core 12. The preset moving distance is compared with the actual moving distance. If the deviation value, that is, the difference between the preset moving distance and the actual moving distance is not zero, a new driving signal is sent to the eccentric driver 23 to control the eccentric driver 23 to drive the second valve core 22 to move until the deviation value returns to zero.

[0094] It should be noted that the term "including" and its variations used in the embodiments of the present invention are open inclusions, that is, "including but not limited to". The term "based on" means "based at least in part on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one other embodiment"; the term "some embodiments" means "at least some embodiments". The modifications of "one" and "multiple" mentioned in the embodiments of the present invention are illustrative and not restrictive. Those skilled in the art should understand that unless the context clearly indicates otherwise, it should be understood as "one or more".

[0095] The various steps described in the method implementation methods provided by the embodiments of the present invention may be performed in different orders and / or in parallel. In addition, the method implementation methods may include additional steps and / or omit the steps shown. The scope of protection of the present invention is not limited in this respect.

[0096] The term "embodiment" in this specification refers to specific features, structures or characteristics described in conjunction with the embodiment that can be included in at least one embodiment of the present invention. The appearance of this phrase in various places in the specification does not necessarily mean the same embodiment, nor does it mean that it is mutually exclusive with other embodiments and is independent or optional. The various embodiments in this specification are described in a related manner, and the same or similar parts between the various embodiments refer to each other. In particular, for the device, equipment, and system embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and the relevant parts refer to the partial description of the method embodiment.

[0097] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of protection. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the attached claims.

Claims

1. An electro-hydraulic servo valve with a rotary direct drive valve as a pilot, characterized in that: include: A main valve, the main valve comprising a first valve body and a first valve core, the first valve body being provided with a main liquid inlet channel, a main liquid outlet channel, a first main input channel and a second main input channel; The first valve core is axially movable and arranged in the first valve body, and the first main input channel and the second main input channel are respectively connected to the axial ends of the first valve core; A pilot valve, the pilot valve comprising a second valve body, a second valve core and an eccentric driver; the second valve body is connected to the first valve body, and a pilot liquid inlet channel, a first pilot liquid outlet channel and a second pilot liquid outlet channel are provided on the second valve body; the pilot liquid inlet channel is connected to the main liquid inlet channel, the first pilot liquid outlet channel is connected to the first main input channel, and the second pilot liquid outlet channel is connected to the second main input channel; the second valve core is axially movable and arranged in the second valve body; the driving end of the eccentric driver is drivingly connected to the second valve core; Among them, the driving end of the eccentric driver rotates and drives the second valve core to move, so that the pilot liquid inlet channel is connected to the corresponding pilot liquid outlet channel, so that a pressure difference is generated between the first main input channel and the second main input channel to drive the first valve core to move, the main liquid outlet channel is connected to the main liquid inlet channel, and the main liquid outlet channel outputs the fluid of the target flow rate.

2. The electro-hydraulic servo valve with a rotary direct drive valve as a pilot according to claim 1, characterized in that: The second valve body is also provided with a first pilot control channel and a second pilot control channel which are interconnected, and along the axial direction of the second valve core, the first pilot control channel, the first pilot liquid outlet channel, the pilot liquid inlet channel, the second pilot liquid outlet channel and the ports of the second pilot control channel are sequentially arranged; The second valve core is hollow along its own axial direction, and a first pilot shoulder, a second pilot shoulder and a third pilot shoulder are sequentially arranged on the second valve core along its own axial direction, a first pilot shoulder channel is provided between the first pilot shoulder and the second pilot shoulder, and a second pilot shoulder channel is provided between the second pilot shoulder and the third pilot shoulder; Wherein, when the second valve core is driven and moved by the eccentric driver, the first pilot shoulder closes the first pilot control channel, the first pilot stage channel connects the pilot liquid inlet channel and the first pilot liquid outlet channel, and the second pilot stage channel connects the second pilot liquid outlet channel and the second pilot control channel; or, the second pilot shoulder closes the second pilot control channel, the second pilot stage channel connects the pilot liquid inlet channel and the second pilot liquid outlet channel, and the first pilot stage channel connects the first pilot liquid outlet channel and the first pilot control channel.

3. The electro-hydraulic servo valve with a rotary direct drive valve as a pilot according to claim 1, characterized in that: The eccentric drive comprises: A driving motor, the driving motor is used to receive a driving signal and rotate along a target direction by a target angle; wherein the driving signal includes the target direction and the target angle; An eccentric output shaft, one end of which is drivingly connected to the driving end of the driving motor, and the other end of which is provided with a driving ball head; a driving ball hole corresponding to the driving ball head is provided on the second valve core, and the driving ball head is rotatably arranged in the driving ball hole; An angle sensor, the angle sensor is used to detect the rotation angle of the drive motor, the rotation angle is used to control the target moving distance, and the target moving distance is the moving distance of the second valve core relative to the second valve body.

4. The electro-hydraulic servo valve with a rotary direct drive valve as a pilot according to claim 1, characterized in that: The pilot valve further comprises a second valve sleeve, which is disposed in the second valve body, the second valve sleeve is hollow along its own axial direction, and the second valve core is axially movable in the second valve sleeve; the second valve sleeve is provided with a pilot liquid inlet through hole, a first pilot liquid outlet through hole, and a second pilot liquid outlet through hole, the pilot liquid inlet through hole is connected to the pilot liquid inlet channel, the first pilot liquid outlet through hole is connected to the first pilot liquid outlet channel, and the second pilot liquid outlet through hole is connected to the second pilot liquid outlet channel; Wherein, when the second valve core is driven and moved by the eccentric driver, the second valve core connects the pilot liquid inlet through hole to the first pilot liquid outlet through hole; or, the second valve core connects the pilot liquid inlet through hole to the second pilot liquid outlet through hole.

5. The electro-hydraulic servo valve with a rotary direct drive valve as a pilot according to claim 1, characterized in that: The main valve also includes: A displacement sensor, the displacement sensor is used to detect an actual moving distance of the first valve core; A controller is electrically connected to the displacement sensor and the eccentric driver, respectively, and is used to compare a preset moving distance with the actual moving distance, and when a deviation value is non-zero, transmit a new driving signal to the eccentric driver to control the eccentric driver to drive the second valve core to move; wherein the deviation value is equal to the difference between the preset moving distance and the actual moving distance.

6. The electro-hydraulic servo valve with a rotary direct drive valve as a pilot according to claim 1, characterized in that: The main liquid outlet channel includes a first main liquid outlet channel and a second main liquid outlet channel, and the first valve body is also provided with a first main control channel and a second main control channel that are interconnected, and along the axial direction of the first valve core, the ports of the first main control channel, the first main liquid outlet channel, the main liquid inlet channel, the second main liquid outlet channel and the second main control channel are sequentially arranged; The first valve core is provided with a first main shoulder, a second main shoulder, a third main shoulder and a fourth main shoulder in sequence along its axial direction, a first main shoulder channel is provided between the first main shoulder and the second main shoulder, a second main shoulder channel is provided between the second main shoulder and the third main shoulder, and a third main shoulder channel is provided between the third main shoulder and the fourth main shoulder; Among them, when the first valve core is driven and moved by the pressure difference, the second main stage channel connects the main liquid inlet channel and the first main liquid outlet channel, and the third main stage channel connects the second main liquid outlet channel and the second main control channel; or, the second main stage channel connects the main liquid inlet channel and the second main liquid outlet channel, and the first main stage channel connects the first main liquid outlet channel and the first main control channel.

7. The electro-hydraulic servo valve with a rotary direct drive valve as a pilot according to claim 6, characterized in that: The main valve further comprises a first valve sleeve, which is arranged in the first valve body, is hollow along its own axial direction, and the first valve core is axially movable in the first valve sleeve; the first valve sleeve is provided with a main liquid inlet through hole, a first main liquid outlet through hole, a second main liquid outlet through hole, a first main control through hole and a second main control through hole, the main liquid inlet through hole is connected to the main liquid inlet channel, the first main liquid outlet through hole is connected to the first main liquid outlet channel, the second main liquid outlet through hole is connected to the second main liquid outlet channel, the first main control through hole is connected to the first main control channel, and the second main control through hole is connected to the second main control channel; Wherein, when the first valve core is driven and moved by the pressure difference, the main liquid inlet through hole is connected to the first main liquid outlet through hole, and the second main liquid outlet through hole is connected to the second main control through hole; or, the main liquid inlet through hole is connected to the second main liquid outlet through hole, and the first main liquid outlet through hole is connected to the first main control through hole.

8. The electro-hydraulic servo valve with a rotary direct drive valve as a pilot according to claim 7, characterized in that: The first valve sleeve is provided with a plurality of the main liquid inlet through holes, a plurality of the first main liquid outlet through holes, a plurality of the second main liquid outlet through holes, a plurality of the first main control through holes and a plurality of the second main control through holes. The plurality of the main liquid inlet through holes, the plurality of the first main liquid outlet through holes, the plurality of the second main liquid outlet through holes, the plurality of the first main control through holes and the plurality of the second main control through holes are uniformly distributed along the circumference of the first valve sleeve.

9. A control method for an electro-hydraulic servo valve with a rotary direct drive valve as a pilot according to any one of claims 1 to 8, characterized in that: include: The fluid is received through the main liquid inlet channel of the first valve body; wherein the first valve body is also provided with a main liquid outlet channel, a first main input channel and a second main input channel; the first valve core is axially movable and arranged in the first valve body, and the first main input channel and the second main input channel are respectively connected to the axial ends of the first valve core; The driving signal is received through an eccentric driver; wherein the driving end of the eccentric driver is in transmission connection with a second valve core, the second valve core is axially movable and arranged in a second valve body, the second valve body is connected to the first valve body, and a pilot liquid inlet channel, a first pilot liquid outlet channel and a second pilot liquid outlet channel are arranged on the second valve body, the pilot liquid inlet channel is connected to the main liquid inlet channel, the first pilot liquid outlet channel is connected to the first main input channel, and the second pilot liquid outlet channel is connected to the second main input channel; In response to the driving signal, the driving end of the eccentric driver rotates and drives the second valve core to move, so that the pilot liquid inlet channel is connected to the corresponding pilot liquid outlet channel; The fluid flows from the pilot inlet channel into the corresponding pilot outlet channel, so that a pressure difference is generated between the first main input channel and the second main input channel, so as to drive the first valve core to move; The main liquid outlet channel is communicated with the main liquid inlet channel to output the fluid at a target flow rate.

10. The control method according to claim 9, characterized in that: Also includes: detecting an actual moving distance of the first valve core; comparing a preset moving distance with the actual moving distance; When the deviation value is non-zero, a new driving signal is transmitted to the eccentric driver to control the eccentric driver to drive the second valve core to move; wherein the deviation value is equal to the difference between the preset moving distance and the actual moving distance.

Images