WO2020057072A1

WO2020057072A1 - Threaded insertion type rotary direct-drive electro-hydraulic servo valve with harmonic speed reducer

Info

Publication number: WO2020057072A1
Application number: PCT/CN2019/078449
Authority: WO
Inventors: 赵言正; 周小云; 王刚; 蒯佳君; 李建伟
Original assignee: 江苏钧微动力科技有限公司
Priority date: 2018-09-18
Filing date: 2019-03-18
Publication date: 2020-03-26
Also published as: CN108953276A

Abstract

Disclosed is a threaded insertion type rotary direct-drive electro-hydraulic servo valve with a harmonic speed reducer. A direct-current brushless servo motor (1) and a harmonic speed reducer (3) are used as an electromechanical conversion part of the threaded insertion type rotary direct-drive electro-hydraulic servo valve, so that the requirement for the starting torque of the servo motor is reduced, the size of the conversion part is reduced, and the stability of the servo valve at the zero position is guaranteed. The servo valve comprises the direct-current brushless servo motor (1), a valve body assembly (2) and the harmonic speed reducer (3), wherein the valve body assembly (2) comprises a valve core (4), a valve sleeve (5), an upper end cover assembly (6) and a lower end cover assembly (7); an output shaft (33) of the direct-current brushless servo motor (1) is fixedly connected to an input shaft (31) of the harmonic speed reducer, and an output shaft (32) of the harmonic speed reducer is connected to an outwardly-protruding part of a central shaft (41) of the valve core (4); and an outer thread (61) is provided on an outer circumferential face of the upper end cover assembly (6), and the outer thread is used for installation and connection with an integrated valve block.

Description

Threaded cartridge rotary direct drive electro-hydraulic servo valve with harmonic reducer

Technical field

The invention relates to the technical field of electro-hydraulic servo valves, in particular to a screw-inserted rotary direct-drive electro-hydraulic servo valve with a harmonic reducer.

Background technique

The electro-hydraulic servo valve is a key component of the electro-hydraulic servo control system. It is both an electro-hydraulic conversion element and a power amplification element. It connects the electrical part with the hydraulic part to achieve the conversion and amplification of the electro-hydraulic signal. The degree determines the performance of the entire electro-hydraulic servo control system. With its high accuracy and fast response, it is widely used in machinery, automobiles, ships, aviation, aerospace and robotics.

At present, with the expansion of the application field of electro-hydraulic servo systems, the application of robots has also put forward higher requirements for electro-hydraulic servo valves: high frequency response, high reliability, strong anti-pollution ability, simple structure, small size, and use. Convenient maintenance, low cost, and easy integration. Traditional electro-hydraulic servo valves have been difficult to meet the above requirements. The current mainstream miniature electro-hydraulic servo valves are the Moog 30 series, E024 series, and 242, which are all complicated to install. The internal elastic components of the hydraulic servo valve make its service life unsatisfactory for robot applications.

Therefore, in the field of robots, there is an urgent need to independently develop a high-frequency electro-hydraulic servo valve that is small in size, light in weight, easy to integrate, and extremely reliable in service life, especially a screw-inserted rotary direct-drive electro-hydraulic servo valve. The existing brushless DC brushless servo motors of the existing screw-inserted rotary direct-drive electro-hydraulic servo valve are directly connected to the central axis of the valve core. The electro-hydraulic servo valve requires a frequent start and stop function at a small angle. The large starting torque of the motor makes the DC brushless servo motor large in size and cannot meet the requirements of small size and light weight. The DC brushless servo motor is directly connected to the center axis of the valve core. The zero-position jitter is serious, which makes the valve body's stability at zero position bad.

Summary of the Invention

In view of the above problems, the present invention provides a threaded cartridge rotary direct drive electro-hydraulic servo valve with a harmonic reducer, which uses a DC brushless servo motor and a harmonic reducer as the threaded cartridge rotary direct drive electro-hydraulic servo valve. The electromechanical conversion part reduces the starting torque requirement of the servo motor, reduces the volume of the conversion part, and ensures the stability of the solenoid valve at the zero position.

Threaded plug-in rotary direct-drive electro-hydraulic servo valve with harmonic reducer, which is characterized in that it includes a DC brushless servo motor, a valve body component, and a harmonic reducer. The valve body component includes a valve core and a valve. The output shaft of the DC brushless servo motor is fixedly connected to the input shaft of the harmonic reducer, and the output shaft of the harmonic reducer is connected to the central shaft of the valve core. In the external convex part, an external thread is provided on the peripheral surface of the outer ring of the upper end cap assembly, and the external thread is used for installation and connection with the integrated valve block.

It is further characterized by:

The DC brushless servo motor is arranged at one axial end of the harmonic speed reducer, the valve body component is arranged at the other axial end of the harmonic speed reducer, an outer shell of the DC brushless servo motor and Corresponding end faces of the housing of the harmonic reducer are fixed by screws, and the other end face of the housing of the harmonic reducer and the corresponding end face of the upper end cover assembly are fixed by screws, which ensures that the entire structure is axially upward. small volume;

The output shaft of the DC brushless servo motor and the input shaft of the harmonic reducer are locked and connected by a first hexagonal set screw;

The output shaft of the harmonic reducer and the convex portion of the central shaft of the valve core are locked and connected by a second hexagon socket set screw;

The valve core is arranged in the inner cavity of the valve sleeve, the upper end cover of the valve sleeve is equipped with the upper end cover assembly, the lower end cover of the valve sleeve is equipped with the lower end cover assembly, and the valve The upper end surface of the sleeve corresponds to the first positioning concave ring groove of the upper end cover component, and the lower end surface of the valve sleeve corresponds to the second positioning concave ring groove of the lower end cover component. A second positioning ring is provided to facilitate assembly and debugging;

The lower end of the valve core is provided with a slot structure, which is convenient for assembly and debugging;

The upper end cover assembly specifically includes an upper end cover, an upper end cover upper pressing piece, and an upper end cover lower pressing piece. The upper end cover is provided with an upward convex positioning ring corresponding to an inner groove of an output end of the harmonic reducer. The central area of the convex positioning ring is a first inner recessed hole, and a pressing piece on the upper end cover is fitted and installed in the first inner recessed hole. The lower surface of the pressing piece on the upper end cover fits the first inner hole. The bottom end surface of the recessed hole is arranged, and the center position of the lower surface of the upper end cover is recessed to form a second inner recessed hole. The lower surface of the lower end plate of the upper end cover is provided with the first positioning concave ring groove, and the upper end cover. A lower pressing piece is fitted in an interference fit to the second inner recessed hole, and the upper surface of the lower end pressing piece of the upper end cover is arranged close to the upper surface of the second inner recessed hole. The screw covers the upper end piece and the upper end cover. The upper end cover is connected with the lower pressing piece to form the upper end cover component, and the convex portion of the central axis of the valve core penetrates the center position of the upper end cover component;

The first fastening screw is fastened to the corresponding upper end surface of the upper end cover component and the valve sleeve to ensure convenient and reliable assembly;

A step hole is provided on a portion of the upper end cover corresponding to the central axis, a stepped hole is arranged in the step hole, and a first annular inner groove is provided on the lower surface of the upper end cover. The first annular inner groove is provided with an O-shaped seal ring;

The upper surface of the second inner recessed hole of the upper end cover is provided with a second recessed inner annular groove, and the second inner recessed groove is provided with an O-shaped sealing ring;

The lower end cover assembly includes a lower end cover and a lower end cover pressing plate. The upper surface of the lower end cover is provided with a second positioning concave ring groove. The center of the lower end cover pressing plate is provided with a central circular hole, and a circumferential direction of the central circular hole. Two oil return holes are provided, and the lower end cover and the lower end cover pressure plate are fixedly connected to form a lower end cover component. The central round hole of the lower end cover pressure plate is coaxially arranged with the central hole of the lower end cover. The oil return hole of the lower end cover pressure plate Aligned with the arc-shaped T channel of the lower end cap;

The second fastening screw fastens and connects the corresponding lower end surface of the lower end cover component and the valve sleeve, thereby ensuring convenient and reliable assembly.

After adopting the present invention, the structure of the screw-inserted rotary direct-drive electro-hydraulic servo valve and the harmonic reducer is adopted, which inherits the advantages of the screw-inserted rotary direct-drive electro-hydraulic servo valve and overcomes the zero position control of the servo motor. The shortcomings highlighted at the time; its use of a DC brushless servo motor and a harmonic reducer as the conversion part of the screw-inserted rotary direct drive electro-hydraulic servo valve can help reduce the starting torque requirement of the servo motor, thereby enhancing the servo The adaptability of the motor to external load changes; reducing the zero-position jitter caused by the mechanical characteristics of the servo motor, thereby enhancing the stability of the electro-hydraulic servo valve at the zero position; by appropriately extending the frequent start and stop time of the servo motor, the servo motor is enhanced in Controllability near the zero position; by using the directional arrangement of the servo motor and the harmonic reducer, and the output end of the harmonic reducer and the servo motor and the input end of the valve core are locked with hexagon socket set screws, The hydraulic servo valve has a more compact space structure; through the improvement of process design, the electro-hydraulic servo valve has a better processing technology and assembly technology.

BRIEF DESCRIPTION OF THE DRAWINGS

1 is a schematic diagram of a cross-sectional structure of a front view of the present invention;

2 is a schematic sectional structural view of a valve body of the present invention;

3 is a sectional structural schematic view of the lower valve cover assembly of the present invention and FIG. 2 is a different angle;

The corresponding names in the figure are as follows:

DC brushless servo motor 1, output shaft 11, outer housing 12, valve body assembly 2, harmonic reducer 3, input shaft 31, output shaft 32, housing 33, inner groove 34 at the output end, valve core 4, center shaft 41. Slotted structure 42, valve sleeve 5, first positioning ring 51, second positioning ring 52, upper end cover assembly 6, external thread 61, first positioning concave ring groove 62, upper end cover 63, and convex positioning ring 631 , The first inner recessed hole 632, the second inner recessed hole 633, the second annular inner groove 634, the upper end cover upper plate 64, the step hole 641, the first annular inner groove 642, the upper end cover lower plate 65, the first A fastening screw 66, a lower end cover assembly 7, a second positioning recessed ring groove 71, a lower end cover 72, a lower end cover pressing plate 73, a center circular hole 731, an oil return hole 732, a second fastening screw 74, and a first hexagon socket. Fixing screw 8, second hexagon socket set screw 9.

detailed description

Threaded plug-in rotary direct-drive electro-hydraulic servo valve with harmonic reducer, see Figures 1-3: It includes DC brushless servo motor 1, valve body assembly 2, harmonic reducer 3, valve body assembly 2 includes There are valve core 4, valve sleeve 5, upper end cover assembly 6, lower end cover assembly 7, the output shaft 11 of the DC brushless servo motor 1 is fixedly connected to the input shaft 31 of the harmonic reducer 3, and the output shaft 32 of the harmonic reducer 3 The outer convex part of the central shaft 41 connected to the valve core 4 is provided with an external thread 61 on the peripheral surface of the outer ring of the upper end cap assembly 6, and the external thread 61 is used for installation and connection with the integrated valve block.

The DC brushless servo motor 1 is arranged at the axial end of the harmonic reducer 3, the valve body assembly 2 is disposed at the other axial end of the harmonic reducer 3, the outer shell 12 and the harmonic reducer of the DC brushless servo motor 1 The corresponding end faces of the housing 33 of 3 are fixed by screw connection, and the other end face of the housing 33 of the harmonic reducer 3 and the corresponding end face of the upper end cover assembly 7 are fixed by screw connection, which ensures that the entire structure has a small axial volume;

The output shaft 11 of the DC brushless servo motor 1 and the input shaft 31 of the harmonic reducer 3 are locked and connected by a first hexagon socket set screw 8;

The output shaft 32 of the harmonic reducer 3 and the convex portion of the central shaft 41 of the valve core 4 are locked and connected by a second hexagon socket set screw 9;

A valve core 4 is arranged in the inner cavity of the valve sleeve 5. The upper end cover of the valve sleeve 5 is equipped with an upper end cover assembly 6. The lower end cover of the valve sleeve 5 is equipped with a lower end cover assembly 7. The upper end surface of the valve sleeve 5 corresponds to An upwardly convex first positioning ring 51 is provided at the first positioning concave ring groove 62 of the upper end cover assembly 6, and a lower end of the valve sleeve 5 corresponds to a downwardly convex portion provided at the second positioning concave ring groove 71 of the lower end cover assembly 7. The second positioning ring 52 is convenient for assembly and debugging;

The lower end of the spool 4 is provided with a slotted structure 42, which is convenient for assembly and debugging;

The upper end cover assembly 6 specifically includes an upper end cover 63, an upper end cover upper pressing piece 64, and an upper end cover lower pressing piece 65. The upper end cover 63 is provided with an upward convex positioning ring 631 corresponding to the inner groove 34 of the output end of the harmonic reducer 3. The center area of the convex positioning ring 631 is a first inner recessed hole 632. The upper end cover 64 is fitted in the first recessed hole 632 with a gap. The lower surface of the upper end cover 64 is fitted to the first inner recessed hole 632. The bottom end surface of the upper end cover 63 is recessed to form a second inner recessed hole 633 at the center position of the lower surface. The lower end plate 65 of the upper end cover is provided with a first positioning concave ring groove 62 on the lower surface, and the upper end cover 65 is in interference. Cooperated with the second inner recessed hole 633, the upper surface of the upper end cover lower pressing piece 65 is arranged closely against the upper surface of the second inner recessed hole 633. The screw covers the upper end cover upper piece 64, the upper end cover 63, and the upper end cover lower piece. 65 is connected to form the upper end cover assembly 6, and the convex portion of the central shaft 41 of the spool 4 penetrates the center position of the upper end cover assembly 6;

The first fastening screw 66 fastens and connects the corresponding upper end faces of the upper end cover assembly 6 and the valve sleeve 5 to ensure convenient and reliable assembly;

A stepped hole 641 is provided on the upper end cover pressing piece 64 corresponding to the central axis 41, and a Gray ring is arranged in the step hole. A lower surface of the upper end cover pressing piece 64 is provided with a first annular inner groove 642, and the first annular shape The inner groove 642 is provided with an O-shaped sealing ring;

The upper surface of the second inner recessed hole 633 of the upper end cover 63 is provided with a concave second annular inner groove 634, and the second annular inner groove 634 is provided with an O-shaped sealing ring;

The lower end cover assembly 7 includes a lower end cover 72 and a lower end cover pressing plate 73. The upper surface of the lower end cover 72 is provided with a second positioning concave ring groove 71. The center of the lower end cover pressing plate 73 is provided with a central circular hole 731, and a circumferential direction of the central circular hole 731. Two oil return holes 732 are provided, and the lower end cover 72 and the lower end cover pressing plate 73 are fixed to form the lower end cover assembly 7. The center circular hole 731 of the lower end cover pressing plate 73 is coaxially arranged with the central hole of the lower end cover 72. The lower end cover pressing plate The oil return hole 732 of 73 is aligned with the arc-shaped T channel of the lower end cover 72 (not shown in the figure and belonging to the existing mature structure);

The second fastening screw 74 fastens and connects the corresponding lower end faces of the lower end cover assembly 7 and the valve sleeve 5 to ensure convenient and reliable assembly.

In this technical solution, the assembly relationship between the valve core 4 and the valve sleeve 5, and the passage and oil hole setting and arrangement of the valve sleeve 5 and the upper end cap assembly 6, and the lower end cap assembly 7 are the same as the existing threaded plug-in rotary direct drive. The electro-hydraulic servo valve is the same, so it will not be repeated here.

The structure of the screw-inserted rotary direct-drive electro-hydraulic servo valve and harmonic reducer inherits the advantages of the screw-inserted rotary direct-drive electro-hydraulic servo valve and overcomes the outstanding characteristics of the servo motor during zero position control. Disadvantages: It uses a DC brushless servo motor and a harmonic reducer as the conversion part of the screw-inserted rotary direct drive electro-hydraulic servo valve, which can help reduce the starting torque requirement of the servo motor, thereby enhancing the servo motor's external load change. Adaptability; reduce the zero position jitter caused by the mechanical characteristics of the servo motor, thereby enhancing the stability of the electro-hydraulic servo valve at the zero position; by appropriately extending the frequent start and stop time of the servo motor, the servo motor can be strengthened near the zero position. Controllability; by adopting the directional arrangement of the servo motor and the harmonic reducer, and the output end of the harmonic reducer and the servo motor and the input end of the valve core are locked with the hexagonal set screws, the electro-hydraulic servo valve has more Compact space structure; through the improvement of process design, the electro-hydraulic servo valve has better processing technology and assembly technology.

The specific embodiments of the present invention have been described in detail above, but the content is only the preferred embodiments created by the present invention, and cannot be considered to limit the implementation scope of the invention creation. All equal changes and improvements made in accordance with the scope of the present invention shall still fall within the scope of this patent.

Claims

Threaded plug-in rotary direct-drive electro-hydraulic servo valve with harmonic reducer, which is characterized in that it includes a DC brushless servo motor, a valve body component, and a harmonic reducer. The valve body component includes a valve core and a valve. The output shaft of the DC brushless servo motor is fixedly connected to the input shaft of the harmonic reducer, and the output shaft of the harmonic reducer is connected to the central shaft of the valve core. In the external convex part, an external thread is provided on the peripheral surface of the outer ring of the upper end cap assembly, and the external thread is used for installation and connection with the integrated valve block.
The threaded cartridge rotary direct drive electro-hydraulic servo valve with a harmonic reducer according to claim 1, wherein the DC brushless servo motor is arranged at an axial end of the harmonic reducer, and The valve body assembly is arranged at the other axial end of the harmonic reducer, and the outer shell of the DC brushless servo motor and the corresponding end face of the housing of the harmonic reducer are fixed by a screw connection. The other end surface of the reducer casing and the corresponding end surface of the upper end cover assembly are fixed by screw connection.
The threaded cartridge rotary direct drive electro-hydraulic servo valve with a harmonic reducer according to claim 1, wherein the output shaft of the DC brushless servo motor passes through the input shaft of the harmonic reducer The first hexagon socket set screw locks the connection.
The threaded plug-in rotary direct-drive electro-hydraulic servo valve with a harmonic reducer according to claim 1, wherein the output shaft of the harmonic reducer and the central axis of the valve core are convex Partially lock the connection by a second hexagon socket set screw.
The threaded plug-in rotary direct-drive electro-hydraulic servo valve with a harmonic reducer according to claim 1, wherein the valve core is arranged in the inner cavity of the valve sleeve, and the upper part of the valve sleeve is The end cover is provided with the upper end cover assembly, and the lower end cover of the valve sleeve is provided with the lower end cover assembly. The upper end surface of the valve sleeve is provided at a position corresponding to the first positioning concave ring groove of the upper end cover assembly. A convex first positioning ring is provided, and the lower end surface of the valve sleeve corresponds to a convex second positioning ring at a second positioning concave ring groove of the lower end cap assembly; a lower groove of the valve core is provided with a slot structure
The threaded plug-in rotary direct-drive electro-hydraulic servo valve with a harmonic speed reducer according to claim 5, wherein the upper end cover assembly specifically comprises an upper end cover, an upper end cover upper pressing piece, and an upper end cover lower pressing piece. The upper end cover is provided with an upward convex positioning ring corresponding to an inner groove of an output end of the harmonic reducer, and a central area of the upward convex positioning ring is a first inner recessed hole, and the upper end cover has a pressing gap. Fitted and installed in the first recessed hole, the lower surface of the upper end cover is arranged to fit the bottom end surface of the first recessed hole, and the center position of the lower surface of the upper end cover is recessed to form a first Two inner recessed holes, the first positioning recessed ring groove is provided on the lower surface of the upper end cover lower pressing piece, the upper end cover lower pressing piece is fitted in an interference fit to the second inner recessed hole, and the upper end cover is under the upper end cover The upper surface of the pressing piece is arranged close to the upper surface of the second inner recessed hole. The screw connects the upper pressing piece of the upper end cover, the upper end cover, and the lower pressing piece of the upper end cover to form the upper end cover component. The central axis of the valve core is convex outward. Partially penetrates the center position of the upper end cap assembly.
The threaded plug-in rotary direct drive electro-hydraulic servo valve with a harmonic speed reducer according to claim 6, wherein a first fastening screw is fastened to the upper end cover assembly and the corresponding upper end face of the valve sleeve.
The threaded plug-in rotary direct-drive electro-hydraulic servo valve with a harmonic reducer according to claim 6, characterized in that a stepped hole on the upper end cover corresponding to the central shaft is provided with a stepped hole, so A Gray ring is arranged in the step hole, a first annular inner groove is provided on the lower surface of the pressing plate on the upper end cover, and an O-shaped seal ring is provided on the first annular inner groove; An upper surface of the two inner concave holes is provided with a second concave inner annular groove, and the second annular inner groove is provided with an O-shaped seal ring.
The threaded plug-in rotary direct-drive electro-hydraulic servo valve with a harmonic reducer according to claim 5, wherein the lower end cover assembly includes a lower end cover, a lower end cover pressing plate, and an upper surface of the lower end cover is provided. There is a second positioning concave ring groove, a center circular hole is provided in the center of the lower end cover pressure plate, and two oil return holes are provided in the circumferential direction of the center circular hole, and the lower end cover and the lower end cover pressure plate are fixedly connected to form a lower end cover. Component, the central circular hole of the lower end cover pressure plate is coaxially arranged with the central hole of the lower end cover, and the oil return hole of the lower end cover pressure plate is aligned with the arc-shaped T channel of the lower end cover.
The threaded plug-in rotary direct-drive electro-hydraulic servo valve with a harmonic speed reducer according to claim 9, wherein a second fastening screw is fastened to the corresponding lower end surface of the lower end cover assembly and the valve sleeve.