CN114483692A - Rotary direct drive type electro-hydraulic servo valve - Google Patents
Rotary direct drive type electro-hydraulic servo valve Download PDFInfo
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- CN114483692A CN114483692A CN202210055442.0A CN202210055442A CN114483692A CN 114483692 A CN114483692 A CN 114483692A CN 202210055442 A CN202210055442 A CN 202210055442A CN 114483692 A CN114483692 A CN 114483692A
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- valve core
- valve
- drive
- section
- drive motor
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
- F15B13/021—Valves for interconnecting the fluid chambers of an actuator
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K31/00—Actuating devices; Operating means; Releasing devices
- F16K31/02—Actuating devices; Operating means; Releasing devices electric; magnetic
- F16K31/04—Actuating devices; Operating means; Releasing devices electric; magnetic using a motor
Abstract
The invention relates to a rotary direct drive type electro-hydraulic servo valve which comprises a controller, a drive motor connected with the controller, and a valve body connected with the drive motor, wherein a valve core is sleeved in the valve body, a flow channel is arranged in the center of the valve body and the valve core, a rotary shaft of the drive motor is inserted into the valve core after being inserted into the valve body, a support structure used for reducing friction at the joint of the rotary shaft of the drive motor and the valve core and a flexible structure arranged in the valve core and used for reducing a side gap between the drive motor and the valve body caused by the reaction force of the valve core on the drive motor are arranged in the valve core. Compared with the prior art, the servo valve has the advantages of reducing friction of a driving structure, improving stability of the servo valve, prolonging service life and the like.
Description
Technical Field
The invention relates to the technical field of hydraulic control elements, in particular to a rotary direct-drive electro-hydraulic servo valve.
Background
The direct-drive electro-hydraulic servo valve adopts an electro-mechanical conversion device to directly drive the valve core of the main valve, overcomes the insuperable obstacles of poor anti-pollution capability, large internal leakage, harsh processing technology and the like of the traditional mechanical feedback electro-hydraulic servo valve with a preposition level represented by a double-nozzle baffle servo valve and a jet pipe servo valve, and has the advantages of simple structure, low cost, high reliability, easy self-detection and the like. The existing rotary direct-drive electro-hydraulic servo valve mostly adopts a drive interface in the form of an eccentric small ball pair to realize the conversion of the rotary motion of a torque motor and the linear motion of a main valve core, because the motor rotates and is vertical to the linear motion direction of a slide valve, the direct-drive valve in the structural form is more compact relative to a coaxial direct-drive structural form and is insensitive to the external vibration in the motion direction of the main valve core. However, the small ball in the driving interface structure of the eccentric small ball pair directly generates line contact friction with the valve core, and the abrasion is serious; and the valve core can also rotate around the shaft, so that the phenomenon of clamping stagnation caused by instability of the valve core is easy to occur. The existing rotary direct drive type electro-hydraulic servo valve needs to solve the problems of friction and abrasion of a drive interface structure and instability and clamping stagnation of a valve core urgently.
Chinese patent CN207609815U discloses a direct drive servo valve with a push-pull structure, which utilizes a flexible rod structure connected with lead screws disposed at two ends of a valve core to realize redundant configuration of a direct drive valve driving mechanism, and when one end fails, the other end can continue to work, but the direct drive servo valve cannot be applied to a rotary direct drive electro-hydraulic servo valve structure. Chinese patent CN211288293U discloses a cartridge type rotary direct-drive electro-hydraulic servo valve, in which a hydraulic amplification mechanism is designed between an actuating driver and a valve core, so as to reduce the torque requirement of the servo valve on an actuator, but this patent can only be applied to a rotary direct-drive valve with a valve core rotating, but cannot be applied to a rotary direct-drive valve with a valve core moving linearly. Therefore, a new structure capable of solving the problems of frictional wear of the driving interface structure of the rotary direct-drive electro-hydraulic servo valve and instability and clamping stagnation of the valve core is needed to be designed.
Disclosure of Invention
The present invention is directed to overcoming the above-mentioned shortcomings of the prior art and providing a rotary direct-drive electrohydraulic servo valve.
The purpose of the invention can be realized by the following technical scheme:
a rotary direct drive type electro-hydraulic servo valve comprises a controller, a drive motor connected with the controller, and a valve body connected with the drive motor, wherein a valve core is sleeved in the valve body, a flow channel is arranged in the center of the valve body and the valve core, a rotary shaft of the drive motor is inserted into the valve core after being inserted into the valve body, a valve core main body, a supporting structure used for reducing friction at the joint of the rotary shaft of the drive motor and the valve core, and a flexible structure arranged in the valve core main body and used for reducing a side gap between the drive motor and the valve body caused by the reaction force of the valve core on the drive motor are arranged in the valve core main body.
The center of the valve core main body is provided with the flow channel, and the support structure is arranged on the circumferential direction of the flow channel. The supporting structure is provided with a through hole with the same axis as the flow channel. In the servo valve of the invention, the axial direction of the valve core body is taken as an x axis, the radius direction of a section parallel to the axial direction is taken as a y axis, the direction vertical to the axial direction is taken as a z axis, and a clearance in the y direction for accommodating the displacement motion of the valve core body in the y direction is reserved between the support structure and the valve core body.
Further, the support structure may employ a rolling bearing or a sliding bearing.
The flexible structure is arranged on two sides of the supporting structure in the x direction. The size of the flexible structure in the x direction is far larger than that in the z direction, the size of the flexible structure in the z direction is far larger than that in the y direction, and the cross section of the flexible structure in the x direction is rectangular or circular.
Furthermore, a sunken hole is formed in the middle of the flow channel of the valve body, and a supporting piece used for positioning the tail end of the rotating shaft of the driving motor is accommodated in the sunken hole.
In the servo valve of the present invention, the rotation shaft of the drive motor is provided with an eccentric structure.
As a preferable mode, the eccentric structure is a centering-eccentric-centering variable cross-section shaft structure, and comprises a centering shaft section, an eccentric shaft section and a centering variable cross-section shaft section which are sequentially arranged, the diameter size of the eccentric shaft section is the same as that of a through hole of a supporting structure in the valve core, the eccentric shaft section is inserted into the supporting structure in the valve core, the diameter size of the centering variable cross-section shaft section at the tail end is the same as that of a sunken hole of a flow passage of the valve body, and the centering variable cross-section shaft section at the tail end is inserted into the supporting piece of the valve body.
As another preferable mode, the eccentric structure includes an eccentric rotating shaft and a ball body disposed at an end of the eccentric rotating shaft, a diameter of the ball body is the same as a diameter of the through hole of the support structure, the ball body is inserted into the support structure, and a center of the ball body is at the same height as a central axis of the valve core.
Compared with the prior art, the rotary direct-drive electro-hydraulic servo valve provided by the invention at least comprises the following beneficial effects:
1) the invention changes the realization principle of the driving interface by designing the valve core with the flexible structure and the supporting structure, the flexible structure enables the valve core to realize pure axial linear displacement without rotating around a shaft, the supporting structure greatly reduces the friction of the driving structure, improves the stability and the service life of the servo valve, and has simple structure, safety and reliability.
2) The flexible structure is designed, so that the displacement of the eccentric shaft of the motor in the direction vertical to the motion direction of the valve core can be effectively absorbed, the friction between the valve core and the valve core is reduced, the service life of the servo valve is prolonged, and the side gap leakage caused by the reaction force of the valve core on the motor can also be reduced;
3) the middle part of the flexible structure is provided with a supporting structure, and the tail end of the motor shaft is provided with a supporting piece, so that the friction of the joint of the rotating shaft of the motor and the valve core can be reduced, and the rotation precision of the motor is ensured.
Drawings
FIG. 1 is a schematic sectional view of an embodiment of a rotary direct-drive electrohydraulic servo valve;
FIG. 2 is a schematic top sectional view of a valve element of an embodiment of a rotary direct-drive electrohydraulic servo valve;
FIG. 3 is a schematic view of a first structure form of a rotating shaft of a driving motor of the rotary direct-drive electro-hydraulic servo valve in the embodiment;
FIG. 4 is a schematic view of a second structure form of a rotary shaft of a driving motor of the rotary direct-drive electro-hydraulic servo valve in the embodiment;
the reference numbers in the figures indicate: 1. the device comprises a controller, 2, a driving motor, 3, a pressure plate, 4, a valve body, 5, a support piece, 6 and a valve core; 7. the valve core comprises a valve core main body, 8, a flexible structure, 9, a supporting structure and 10, and an eccentric structure.
Detailed Description
The invention is described in detail below with reference to the figures and specific embodiments. It is to be understood that the embodiments described are only a few embodiments of the present invention, and not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, shall fall within the scope of protection of the present invention.
Examples
The invention relates to a rotary direct drive type electro-hydraulic servo valve, which has a structure shown in figures 1 and 2. As shown in fig. 1 and 2, the servo valve includes a controller 1, a driving motor 2, a pressure plate 3, a valve body 4, a support 5, and a valve element 6. The valve core 6 is sleeved in the valve body 4, and a flow passage is arranged in the center of the valve body 4 and the valve core 6. A sunken hole is formed in the middle of the flow passage of the valve body 4 to accommodate the support member 5, and the sunken hole is formed in the bottom of the flow passage of the valve core 6.
In a specific embodiment of the present invention, the supporting member 5 may be a rolling bearing, which has a positioning function, and can ensure the rotation precision of the rotating shaft of the motor 2, and simultaneously avoid the direct friction between the rotating shaft of the motor 2 and the valve body 4.
In another specific embodiment of the present invention, the supporting member 5 may also be a sliding bearing, which has a positioning function, so as to ensure the rotation precision of the rotating shaft of the motor 2, and simultaneously avoid the direct friction between the rotating shaft of the motor 2 and the valve body 4.
As shown in fig. 2, the spool 6 includes a spool main body 7, a flexible structure 8, and a support structure 9; the valve core main body 7, the flexible structure 8 and the supporting structure 9 are integrated, can be made of the same material, and can be manufactured in an additive manufacturing mode and the like. The valve core main body 7 is hollow inside and used for accommodating the flexible structure 8 and the supporting structure 9; a flow passage is provided in the center of the valve body 7. . The supporting structure 9 is arranged on the circumferential direction of the flow channel and used for reducing friction at the joint of the rotating shaft of the driving motor 2 and the valve core 6 and ensuring the rotating precision of the driving motor 2, a through hole is formed in the supporting structure 9, and the through hole of the supporting structure 9 and the flow channel of the valve core 6 are coaxial.
Further, with the axial direction of the valve element main body 7 in fig. 2 as the x-axis, the radial direction of the cross section parallel to the axial direction as the y-axis, and the direction of the cross section perpendicular to the axial direction as the z-axis, the dimension of the flexible structure 8 in the x-direction is much larger than the dimension in the z-direction, the dimension of the flexible structure 8 in the z-direction is much larger than the dimension in the y-direction, and the cross section of the flexible structure 8 in the x-direction is rectangular or circular. A gap in the y direction is reserved between the supporting structure 9 and the valve core main body 7 to accommodate the displacement movement of the supporting structure in the y direction, and the supporting structure 9 is guaranteed not to interfere and collide with the valve core main body 7 when the supporting structure is displaced.
The flexible structures 8 are arranged on both sides of the support structure 9 in the x-direction, and the flexible structures 8 are symmetrical structures. A gap in the y direction is reserved between the flexible structure 8 and the valve core main body 7 to accommodate the displacement movement of the flexible structure 8 in the y direction, and the flexible structure 8 is guaranteed not to interfere and collide with the valve core main body 7 when being deformed. In this embodiment, the flexible structure 8 is geometrically characterized in that its dimension in the x-direction is much greater than its dimension in the z-direction, which is much greater than its dimension in the y-direction, and its cross-sectional shape in the x-direction is rectangular. In other embodiments, the flexible structure 8 is geometrically characterized by an x-dimension substantially greater than a z-dimension, the z-dimension substantially greater than a y-dimension, and the x-cross-sectional shape being circular. The flexible structure 8 can absorb the motion of the rotating shaft of the driving motor 2 applied to the y direction, the valve core main body 7 hardly generates displacement in the y direction through the bending deformation of the flexible structure in the y direction, and the simple axial displacement of the valve core 6 means the reduction of the radial force between the valve core 6 and the valve body 4, so that the friction wear between the valve core 6 and the valve body 4 is reduced, and the service life of the servo valve is prolonged; the flexible structure 8 can also reduce the backlash of the drive motor 2 and the valve body 4 caused by the reaction force of the valve core 6 to the drive motor 2, thereby reducing the leakage amount.
As an embodiment, the supporting structure 9 may adopt a rolling bearing, which can reduce friction at the connection between the rotating shaft of the driving motor 2 and the valve core 6 and ensure the rotation precision of the driving motor 2.
As another embodiment, the supporting structure 9 may be a sliding bearing, which can reduce friction at the connection between the rotating shaft of the driving motor 2 and the valve core 6 and ensure the rotation precision of the driving motor 2.
In the present embodiment, the rotating shaft of the driving motor 2 is designed with an eccentric structure 10, and the eccentric structure 10 can have two forms. One is a centering-eccentric-centering variable cross-section shaft, namely, a rotating shaft of the driving motor 2 comprises a centering shaft section, an eccentric shaft section and a centering variable cross-section shaft section which are sequentially arranged. As shown in fig. 3, the nominal diameter of the eccentric shaft section is the same as the nominal diameter of the through hole of the support structure 9 inside the valve core 6, the eccentric shaft section is inserted into the support structure 9 inside the valve core 6, the nominal diameter of the centering shaft section at the tail end is the same as the nominal diameter of the flow channel counterbore of the valve body 4, and the centering shaft section at the tail end is inserted into the support 5 in the flow channel counterbore of the valve body 4. The other is that the end of the eccentric rotating shaft of the driving motor 2 is provided with a small ball, as shown in fig. 4, the nominal diameter of the small ball is the same as that of the through hole of the supporting structure 9 inside the valve core 6, the small ball is inserted into the supporting structure 9 inside the valve core 6, and the center of the small ball is at the same height as the central axis of the valve core 6, and the eccentric structure 10 designed according to the structure of the small ball does not need to be inserted into the supporting member 5.
As a preferred embodiment, the rotating shaft of the driving motor 2 can rotate in an angle range of-20 degrees to 20 degrees, the opening degree of the valve core 6 can be changed when the rotating shaft of the driving motor 2 rotates in the angle range of-20 degrees to 20 degrees, and the valve port is in a fully closed state when the rotating shaft of the driving motor 2 does not rotate; when the rotating shaft of the driving motor 2 rotates to-20 degrees or 20 degrees, the valve port is in a full-open state.
The invention changes the realization principle of the driving interface by arranging the valve core with the flexible structure and the supporting structure, the flexible structure enables the valve core to realize pure axial linear displacement without rotating around a shaft, the supporting structure greatly reduces the friction of the driving structure, improves the stability and the service life of the servo valve, and has simple structure, safety and reliability. In addition, the flexible structure can effectively absorb the displacement of the eccentric shaft of the motor in the direction vertical to the motion direction of the valve core, reduce the friction between the valve core and the valve core so as to prolong the service life of the servo valve and also reduce the side gap leakage caused by the reaction force of the valve core on the motor; and the middle part of the flexible structure is also provided with a supporting structure, and the tail end of the motor shaft is provided with a supporting piece, so that the friction at the joint of the rotating shaft of the motor and the valve core can be reduced, and the rotation precision of the motor can be ensured.
While the invention has been described with reference to specific embodiments, the invention is not limited thereto, and those skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope of the invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (10)
1. The rotary direct drive type electro-hydraulic servo valve is characterized by comprising a controller (1), a drive motor (2) connected with the controller (1) and a valve body (4) connected with the drive motor (2), wherein a valve core (6) is sleeved in the valve body (4), a flow channel is arranged in the center of the valve body (4) and the center of the valve core (6), a rotary shaft of the drive motor (2) is inserted into the valve core (6) after being inserted into the valve body (4), a supporting structure (9) used for reducing friction at the joint of the rotary shaft of the drive motor (2) and the valve core (6) and a flexible structure (8) arranged in the valve core (6) and used for reducing side clearance between the drive motor (2) and the valve body (4) caused by reaction force of the valve core (6) on the drive motor (2) are arranged in the valve core (6).
2. The rotary direct-drive electrohydraulic servo valve according to claim 1, characterized in that said spool (6) further includes a spool body (7), said spool body (7) having said flow channel at a center thereof, said flow channel being circumferentially provided with said support structure (9), said flexible structure (8) being provided at both sides of said support structure (9).
3. The rotary direct drive type electrohydraulic servo valve according to claim 2, wherein an axial direction of the valve core body (7) is taken as an x-axis, a radial direction of a cross section parallel to the axial direction is taken as a y-axis, a direction of the cross section perpendicular to the axial direction is taken as a z-axis, a dimension of the flexible structure (8) in the x-direction is much larger than a dimension of the z-direction, the dimension of the flexible structure (8) in the z-direction is much larger than the dimension of the y-direction, a cross section of the flexible structure (8) in the x-direction is rectangular or circular, and the flexible structure (8) is provided on both sides of the support structure (9) in the x-direction.
4. A rotary direct-drive electrohydraulic servo valve according to claim 2, characterized in that said support structure (9) is provided with a through hole coaxial with said flow channel.
5. Rotary direct-drive electro-hydraulic servo valve according to claim 4, characterized in that the support structure (9) is a rolling bearing or a plain bearing.
6. A rotary direct-drive electrohydraulic servo valve according to claim 4, characterized in that a rotation shaft of said drive motor (2) is provided with an eccentric structure (10).
7. The rotary direct drive type electrohydraulic servo valve according to claim 6, wherein a sunken hole is formed in a middle position of the flow passage of the valve body (4), and a support member (5) for positioning an end of a rotary shaft of the drive motor (2) is accommodated in the sunken hole.
8. The rotary direct-drive electrohydraulic servo valve according to claim 7, characterized in that said eccentric structure (10) is a centered-eccentric-centered variable cross-section shaft structure comprising a centered shaft section, an eccentric shaft section and a centered variable cross-section shaft section which are sequentially arranged, the diameter of the eccentric shaft section is the same as the diameter of the through hole of the support structure (9) inside said valve core (6), the eccentric shaft section is inserted into the support structure (9) inside the valve core (6), the diameter of the centered variable cross-section shaft section at the end is the same as the diameter of the sunken hole of the flow passage of the valve body (4), and the centered variable cross-section shaft section at the end is inserted into the support (5) of the valve body (4).
9. Rotary direct-drive electrohydraulic servo valve according to claim 6, characterized in that said eccentric structure (10) comprises an eccentric rotation shaft and a ball arranged at the end of the eccentric rotation shaft, the diameter of said ball being the same size as the diameter of the through hole of said support structure (9), said ball being inserted in said support structure (9) with its centre of sphere at the same height as the central axis of the spool (6).
10. Rotary direct-drive electrohydraulic servo valve according to claim 4, characterized in that a y-direction clearance is left between said support structure (9) and said spool body (7) to accommodate the displacement movement of itself in the y-direction.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210055442.0A CN114483692B (en) | 2022-01-18 | 2022-01-18 | Rotary direct drive type electro-hydraulic servo valve |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210055442.0A CN114483692B (en) | 2022-01-18 | 2022-01-18 | Rotary direct drive type electro-hydraulic servo valve |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114483692A true CN114483692A (en) | 2022-05-13 |
| CN114483692B CN114483692B (en) | 2022-12-16 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210055442.0A Active CN114483692B (en) | 2022-01-18 | 2022-01-18 | Rotary direct drive type electro-hydraulic servo valve |
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| CN (1) | CN114483692B (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5510198A (en) * | 1979-07-02 | 1980-01-24 | Hitachi Ltd | Direct-acting servo valve |
| CN102493968A (en) * | 2011-12-30 | 2012-06-13 | 北京理工大学 | Method and device for energy-saving control of elastic load based on electrohydraulic servo drive |
| DE202018105534U1 (en) * | 2018-09-26 | 2018-10-04 | Johnson Electric Germany GmbH & Co. KG | Valve |
| CN112984123A (en) * | 2021-02-01 | 2021-06-18 | 上海衡拓液压控制技术有限公司 | Valve core driving conversion structure of servo valve |
-
2022
- 2022-01-18 CN CN202210055442.0A patent/CN114483692B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5510198A (en) * | 1979-07-02 | 1980-01-24 | Hitachi Ltd | Direct-acting servo valve |
| CN102493968A (en) * | 2011-12-30 | 2012-06-13 | 北京理工大学 | Method and device for energy-saving control of elastic load based on electrohydraulic servo drive |
| DE202018105534U1 (en) * | 2018-09-26 | 2018-10-04 | Johnson Electric Germany GmbH & Co. KG | Valve |
| CN112984123A (en) * | 2021-02-01 | 2021-06-18 | 上海衡拓液压控制技术有限公司 | Valve core driving conversion structure of servo valve |
Non-Patent Citations (1)
| Title |
|---|
| 甄亮等: "摩擦非线性对大型风力机变桨距电液伺服动态加载系统的影响", 《液压与气动》 * |
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| CN114483692B (en) | 2022-12-16 |
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