Nozzle-baffle servo valve baffle for inhibiting vortex street oscillation

Abstract

The nozzle-baffle servo valve baffle comprises an armature, a spring tube, a nozzle, an integrated rod and a valve element, the integrated rod is sequentially composed of an assembly structure, a baffle structure and a feedback structure from top to bottom, and the assembly structure of the integrated rod is provided with the armature and the spring tube; two nozzles are symmetrically arranged on the left side and the right side of the baffle structure of the integrated rod, and the tail end of the feedback structure of the integrated rod is connected with the valve element. Compared with the prior art, a baffle and a feedback rod of a servo valve in the prior art are combined into a whole, transition between a baffle structure and a feedback structure is smooth, and under the condition that work of the nozzle-baffle servo valve is not affected, a flow separation point at the bottom of an original baffle is eliminated; and the formation of separation vortex at the bottom of the baffle is fundamentally avoided, so that the vortex street phenomenon of a prestage flow field is inhibited, vibration noise and impact are reduced, and the service life of the electro-hydraulic servo valve is prolonged.

Description

Technical Field

[0001] The invention relates to the technical field of hydraulic control valves, and in particular to a nozzle-baffle servo valve baffle for suppressing vortex street oscillation. Background Art

[0002] As a high-performance hydraulic control valve, the electro-hydraulic servo valve is one of the key components that affect the performance of the hydraulic servo system. It is used to connect the electrical and hydraulic parts of the system to achieve electric-hydraulic conversion and power amplification functions. Among them, the research on the nozzle-flapper servo valve started earlier. It has fast dynamic response speed, high sensitivity, good linearity, and small temperature and pressure zero drift. It is widely used in CNC machine tools, locomotives, ships, radars, flight devices and other automatic control equipment that require high-precision control. In order to meet application requirements, the size of the nozzle-flapper servo valve is getting smaller and smaller, the core speed of the pre-stage jet is getting larger and larger, and the high-speed jet is ejected from the nozzle flow. Most of the fluid will flow along the baffle to the wake area and separate at the tail of the baffle to form two rows of vortices. As the Reynolds number of the fluid increases, periodic alternating vortices will form on both sides of the baffle, generating flow field pressure pulsation, causing the servo valve pre-stage self-oscillation. The servo valve pre-stage self-oscillation will form high-frequency noise, and due to the alternating stress generated by the oscillation, the spring tube may suffer fatigue fracture, resulting in failure of the servo valve.

[0003] In order to suppress the self-oscillation phenomenon of the pre-stage of the nozzle-baffle servo valve, Chinese patent CN 206929154 U discloses a servo valve self-oscillation suppression device with an adjustable nozzle baffle distance; Chinese patent CN 207961119 U discloses a nozzle baffle servo valve for suppressing pre-stage cavitation; Chinese patent CN 114893474 B discloses a method for suppressing the self-oscillation of a double nozzle baffle servo valve; the above patents all suppress the oscillation phenomenon of the local flow field between the nozzle and the baffle through structural innovation, but cannot satisfy the suppression of the vortex street oscillation phenomenon in the baffle wake area. Summary of the invention

[0004] The purpose of the present invention is to suppress the problem of damage to the armature assembly caused by vortex street oscillation in the pre-stage of the nozzle-baffle servo valve in the prior art and to provide a nozzle-baffle servo valve baffle for suppressing vortex street oscillation, so as to suppress the generation of vortex streets in the pre-stage flow field of the nozzle-baffle servo valve and improve the service life of the electro-hydraulic servo valve.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] A nozzle-baffle servo valve baffle for suppressing vortex street oscillation comprises an armature, a spring tube, a nozzle, an integrated rod and a valve core.

[0007] The integrated rod is composed of an assembly structure, a baffle structure and a feedback structure from top to bottom. The assembly structure of the integrated rod is provided with an armature and a spring tube. Two nozzles are symmetrically provided on the left and right sides of the baffle structure of the integrated rod. The end of the feedback structure of the integrated rod is connected to the valve core.

[0008] Furthermore, the armature is fixed to the top end of the assembly structure of the integrated rod.

[0009] Furthermore, the assembly structure of the integrated rod is installed on the spring tube by press-fitting.

[0010] Furthermore, the diameter of the baffle structure of the integrated rod is smaller than the inner diameter of the spring tube.

[0011] Furthermore, a sealing ring is provided between the assembly structure of the integrated rod and the spring tube.

[0012] Furthermore, the baffle structure of the integrated rod is provided with planes which are symmetrical on both sides and parallel to the central axis, and the surface of the baffle structure of the integrated rod is provided with grid-like patterns.

[0013] Furthermore, a slot hole is provided in the middle of the valve core, and a feedback ball is provided at the end of the feedback structure of the integrated rod, and the feedback ball is connected to the slot hole on the valve core.

[0014] As a preferred technical solution, the feedback ball is a solid hemispherical structure.

[0015] Furthermore, the baffle structure and the feedback structure of the integrated rod are connected with each other by a smooth transition.

[0016] Furthermore, the main bodies of the assembly structure of the integrated rod and the baffle structure are both cylinders, and the main body of the feedback structure of the integrated rod is a cone.

[0017] Furthermore, in the above, the diameter of the assembly structure of the integrated rod is greater than the diameters of the baffle structure and the feedback structure of the integrated rod.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] The present invention starts from the vortex street oscillation phenomenon in the baffle wake area and designs a nozzle-baffle servo valve baffle for suppressing vortex street oscillation. Taking into account the conditions for vortex street formation, the present invention combines the baffle and feedback rod of the servo valve in the prior art into a whole, and the transition between the baffle structure and the feedback structure is smooth. Without affecting the operation of the nozzle-baffle servo valve, the flow separation point at the bottom of the original baffle is eliminated, and the formation of a separation vortex at the bottom of the baffle is fundamentally avoided, thereby suppressing the vortex street phenomenon in the pre-stage flow field, reducing vibration noise and impact, and increasing the service life of the electro-hydraulic servo valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of the present invention.

[0021] Explanation of the accompanying drawing numbers: 1. armature, 2. spring tube, 3. sealing ring, 4. nozzle, 5. integrated rod, 6. valve core. DETAILED DESCRIPTION

[0022] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0023] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0024] In the description of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0025] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0026] In conjunction with the accompanying drawings, some embodiments of the present invention are described in detail below. In the absence of conflict, the following embodiments and features in the embodiments may be combined with each other.

[0027] Example

[0028] See also Figure 1 The present embodiment provides a nozzle-baffle servo valve baffle for suppressing vortex street oscillation, comprising an armature 1, a spring tube 2, a nozzle 4, an integrated rod 5 and a valve core 6.

[0029] The integrated rod 5 is composed of an assembly structure, a baffle structure and a feedback structure from top to bottom. The assembly structure of the integrated rod 5 is provided with an armature 1 and a spring tube 2. Two nozzles 4 are symmetrically provided on the left and right sides of the baffle structure of the integrated rod 5. The end of the feedback structure of the integrated rod 5 is connected to the valve core 6.

[0030] In this embodiment, the armature 1 is fixed to the top end of the assembly structure of the integral rod 5 .

[0031] In this embodiment, the assembly structure of the integrated rod 5 is installed on the spring tube 2 by press-fitting.

[0032] In this embodiment, the diameter of the baffle structure of the integrated rod 5 is smaller than the inner diameter of the spring tube 2 .

[0033] In this embodiment, a sealing ring 3 is provided between the assembly structure of the integrated rod 5 and the spring tube 2 .

[0034] In this embodiment, the baffle structure of the integrated rod 5 is provided with planes that are symmetrical on both sides and parallel to the central axis, and the surface of the baffle structure of the integrated rod 5 is provided with grid-like patterns.

[0035] In this embodiment, a slot is provided in the middle of the valve core 6 , and a feedback ball is provided at the end of the feedback structure of the integrated rod 5 , and the feedback ball is connected to the slot on the valve core 6 .

[0036] In this embodiment, the feedback ball is a solid hemispherical structure.

[0037] In this embodiment, the baffle structure and the feedback structure of the integrated rod 5 are connected by a smooth transition.

[0038] In this embodiment, the main bodies of the assembly structure of the integrated rod 5 and the baffle structure are both cylinders, and the main body of the feedback structure of the integrated rod 5 is a cone.

[0039] In this embodiment, the diameter of the assembly structure of the integrated rod 5 is greater than the diameters of the baffle structure and the feedback structure of the integrated rod 5 .

[0040] In a more specific implementation, when the armature 1 generates a torque under the action of the coil current, the armature 1 is caused to deflect, which in turn drives the spring tube 2 and the baffle structure of the integrated rod 5 to deflect, the variable throttling hole composed of the baffle structure of the integrated rod 5 and the nozzles 4 on both sides thereof changes, so that the pressure on the left and right sides of the valve core 6 changes, causing the valve core 6 to move, and the movement of the valve core 6 drives the movement of the feedback ball at the end of the feedback structure of the integrated rod 5, and the movement of the valve core 6 is fed back to the baffle structure of the integrated rod 5 and the spring tube 2 through the feedback structure of the integrated rod 5, thereby realizing closed-loop control of the movement of the valve core 6.

[0041] The present invention starts from the vortex street oscillation phenomenon in the baffle wake area and finds that the separation vortex with a fixed separation point is the fundamental cause of the vortex street phenomenon. The integrated rod 5 of the present invention sets a smooth transition between the baffle structure and the feedback structure, eliminates the fixed separation point at the bottom of the original baffle 5, fundamentally avoids the formation of the separation vortex, and suppresses the vortex street phenomenon of the pre-stage flow field. The baffle structure of the integrated rod 5 is symmetrical on both sides and parallel to the plane of the central axis, and the surface is provided with grid-like patterns. When the fluid is sprayed from the nozzle 4 onto the baffle structure of the integrated rod 5, the viscosity of the fluid flowing downward along the integrated rod 5 increases, and the flow rate drops rapidly, so that the flow rate slows down, thereby avoiding the generation of unnecessary self-excited oscillation phenomenon and improving the service life of the electro-hydraulic servo valve.

[0042] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A nozzle-flapper servo valve baffle for suppressing vortex street oscillation, characterized in that: It comprises an armature (1), a spring tube (2), a nozzle (4), an integrated rod (5) and a valve core (6). The integrated rod (5) is composed of an assembly structure, a baffle structure and a feedback structure from top to bottom. An armature (1) and a spring tube (2) are provided on the assembly structure of the integrated rod (5). Two nozzles (4) are symmetrically provided on the left and right sides of the baffle structure of the integrated rod (5). The end of the feedback structure of the integrated rod (5) is connected to a valve core (6).

2. The nozzle-baffle servo valve baffle for suppressing vortex street oscillation according to claim 1, characterized in that: The armature (1) is fixed to the top end of the assembly structure of the integrated rod (5).

3. The nozzle-baffle servo valve baffle for suppressing vortex street oscillation according to claim 1, characterized in that: The assembly structure of the integrated rod (5) is installed on the spring tube (2) by means of press-fitting.

4. The nozzle-baffle servo valve baffle for suppressing vortex street oscillation according to claim 1, characterized in that: The diameter of the baffle structure of the integrated rod (5) is smaller than the inner diameter of the spring tube (2).

5. The nozzle-baffle servo valve baffle for suppressing vortex oscillation according to claim 1, characterized in that: A sealing ring (3) is provided between the assembly structure of the integrated rod (5) and the spring tube (2).

6. The nozzle-flapper servo valve baffle for suppressing vortex oscillation according to claim 1, characterized in that: The baffle structure of the integrated rod (5) is provided with planes which are symmetrical on both sides and parallel to the central axis, and the surface of the baffle structure of the integrated rod (5) is provided with grid-like patterns.

7. The nozzle-baffle servo valve baffle for suppressing vortex oscillation according to claim 1, characterized in that: A slot hole is provided in the middle of the valve core (6), and a feedback ball is provided at the end of the feedback structure of the integrated rod (5), and the feedback ball is connected to the slot hole on the valve core (6).

8. The nozzle-baffle servo valve baffle for suppressing vortex oscillation according to claim 1, characterized in that: The baffle structure and the feedback structure of the integrated rod (5) are connected by a smooth transition.

9. The nozzle-flapper servo valve baffle for suppressing vortex oscillation according to claim 1, characterized in that: The main bodies of the assembly structure of the integrated rod (5) and the baffle structure are both cylinders, and the main body of the feedback structure of the integrated rod (5) is a cone.

10. The nozzle-flapper servo valve baffle for suppressing vortex oscillation according to claim 9, characterized in that: The diameter of the assembly structure of the integrated rod (5) is greater than the diameters of the baffle structure and the feedback structure of the integrated rod (5).

Images