Nozzle flapper servo valve

Abstract

The utility model discloses a nozzle baffle servo valve. The servo valve comprises a valve body, an oil inlet nozzle, an oil return nozzle, a gasket, a support, a lining, a threaded block, a coil, a magnetic ring and the like. A traditional armature, an elastic support and a baffle are made into a whole and fixed to a valve body through screws, a gasket is arranged between the supporting part and the valve body, and the distance between a nozzle and the rotating center of the support can be adjusted. And the bushing wraps the support and the gasket and is matched with the sealing ring to realize sealing. An original design method that a movable sealing ring is arranged on the baffle is changed, and the reliability is higher by using the lining static seal. The coil is sleeved with the magnetic ring, the magnetic ring is composed of two permanent magnets and two magnetizers, threaded holes are formed in the middles of the magnetizers, adjusting screws are arranged in the threaded holes, the magnetic gap between the magnetizers and the cylinder of the bush is conveniently adjusted, and the debugging manufacturability is improved. According to the servo valve, the development requirements of miniaturization, high power-to-weight ratio and high reliability of the servo valve can be met.

Description

Technical Field

[0001] The utility model relates to a servo valve used in an electro-hydraulic servo control system, in particular to a torque motor type electro-hydraulic servo valve. Background Art

[0002] Among the servo valves commonly used in industry, the electro-hydraulic servo valve is an important type. The electro-hydraulic servo valve is a key component in the control system, which can convert low-power electrical energy input into high-power hydraulic output. The core of the electro-hydraulic servo valve lies in the design of the torque motor. Miniaturization, high power-to-weight ratio, and high reliability of the torque motor are the development direction of the nozzle flapper servo valve.

[0003] With the development demand for miniaturization, high power-to-weight ratio and high reliability of hydraulic components, the existing nozzle flapper servo valve cannot meet this requirement. The main problems are as follows:

[0004] The elastic support stiffness is an important design parameter of the servo valve. Since high-pressure oil enters the elastic support, in order to ensure reliability, the thickness of the elastic support wall has certain requirements, which increases the support stiffness. In order to meet the parameter matching requirements, the torque motor needs a larger output torque and cannot be miniaturized.

[0005] Due to the limited space of the torque motor in the structural design, the existing torque motor uses two coils in series, which has a large space volume and a relatively low power density; Utility Model Content

[0006] In order to solve the above problems, the utility model provides a miniaturized nozzle baffle servo valve structure with high power-to-weight ratio and high reliability, so as to achieve the requirements of product miniaturization, high power-to-weight ratio and high reliability.

[0007] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0008] A nozzle baffle servo valve, the servo valve comprises a valve body, a gasket and a support are installed on the valve body, the gasket and the support are sleeved on the support baffle, and the gasket and the support are fixed to the valve body with screws; the bushing wraps the support and the gasket to form a whole, and a sealing ring is provided at the contact position between the bushing and the gasket; the upper and lower surfaces of the support are all oil static pressure.

[0009] Furthermore, a threaded block is provided above the bushing, and the threaded block fixes the bushing on the valve body. Both the threaded block and the bushing are made of brass.

[0010] Furthermore, the servo valve is also provided with an oil inlet nozzle and an oil return nozzle, and the oil inlet nozzle and the oil return nozzle are located on both sides of the protruding part of the support baffle, and the oil from the two nozzles directly acts on the support baffle, and by giving a command signal, the distance from the support baffle part to the two nozzles is changed, and the pressure of the output oil port is changed to realize the servo valve control.

[0011] Furthermore, the servo valve is also provided with a threaded block and a coil, the threaded block and the coil are sequentially mounted on the support baffle, the coil is mounted above the threaded block, the coil is vertically mounted on the bushing cylinder, and a magnetic coating is filled between the coil and the threaded block.

[0012] Furthermore, the coil is covered with a magnetic ring, which consists of two permanent magnets and two magnetic conductors. A threaded hole is opened in the middle of the magnetic conductor, and a left adjusting screw and a right adjusting screw are arranged inside to adjust the air gap of the magnetic circuit.

[0013] The traditional armature, elastic support and baffle are made into one piece and fixed to the valve body with screws. A gasket is set between the support part and the valve body, and the distance between the nozzle and the support rotation center can be adjusted. The bushing wraps the support and the gasket, and cooperates with the sealing ring to achieve sealing. Therefore, the upper and lower surfaces of the support are all oil-hydrostatic, and the support wall thickness does not need to be too thick, as long as it meets the stiffness requirements. The bushing is fixed with a threaded block above the bushing. Both the threaded block and the bushing are made of brass to ensure the isolation of the magnetic circuit. A coil is installed above the threaded block. The coil is sleeved in the bushing cylinder, and a magnetic coating is filled between the coil and the threaded block. The outside of the coil is covered with a magnetic ring, which consists of two permanent magnets and two magnetic conductors. There is a threaded hole in the middle of the magnetic conductor, and an adjusting screw is set inside to facilitate the adjustment of the gap with the bushing cylinder and change the magnetic gap. The magnetic ring is connected to the valve body by screws, and there is a cover outside the magnetic ring for protection. There is a sealing ring between the cover and the valve body to achieve sealing.

[0014] Beneficial effects of this utility model patent:

[0015] The traditional armature, elastic support and baffle are integrated, surrounded by a bushing and sealed with a sealing ring. The thickness of the elastic support wall only needs to meet the stiffness requirements, and there is no need to consider the oil pressure. The smaller support stiffness can make the torque motor easier to drive, so the torque motor design structure can be miniaturized. At the same time, the bushing sealing method used changes the original design method of arranging a dynamic sealing ring on the baffle, and the use of a bushing static seal has higher reliability.

[0016] The single coil is arranged vertically to reduce the coil skeleton, so the coil can be wound in a larger volume and have a larger output torque. At the same time, the adjustment screws set on the magnetic ring make it easier to change the air gap. Compared with the traditional method of using different thickness adjustment gaskets to adjust the air gap, the debugging process of this solution is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a structural principle diagram of the nozzle baffle servo valve of the utility model;

[0018] Figure 2 is a diagram of a magnetic ring structure provided in an embodiment;

[0019] In the figure: 1. valve body; 2. oil inlet nozzle; 3. oil inlet nozzle sealing ring; 4. oil outlet sealing ring; 5. support baffle part; 6. oil return nozzle sealing ring; 7. oil return nozzle; 8. gasket; 9. support; 10. screw; 11. bushing; 12. threaded block; 13. coil; 14. right adjusting screw; 15 left adjusting screw; 16 magnetic ring; 17. cover; 18. screw; 19. magnetic coating; 20. cover seal ring; 21. bushing seal ring;

[0020] 16-1. Permanent magnet; 16-2. Magnetic conductor; 16-3 Threaded hole. DETAILED DESCRIPTION

[0021] Figure 1 The accompanying drawing shows a schematic diagram of the structure of the servo valve proposed by the utility model, which mainly includes a valve body 1, an oil inlet nozzle 2, an oil return nozzle 7 and a gasket 8, a support 9, a bushing 11, a threaded block 12, a coil 13, and a magnetic ring 16.

[0022] The servo valve body 1 is equipped with an oil inlet nozzle 2 and an oil return nozzle 7. The oil from the two nozzles directly acts on the supporting baffle part 5. By giving a command signal, the distance from the supporting baffle part 5 to the two nozzles is changed, the pressure of the output oil port is changed, and the servo valve control is realized.

[0023] The valve body 1 is installed with a gasket 8 and a support 9, which are fixed to the valve body 1 by screws 10. The support 9 and the gasket 8 are wrapped with a bushing 11, and the bushing seal ring 21 is used to achieve sealing. Therefore, the upper and lower surfaces of the support 9 are all oil static pressure, and the wall thickness of the support 9 does not need to be too thick, as long as the rigidity requirements are met. The bushing 11 is fixed to the valve body 1 by a threaded block 12 above the bushing 11. The threaded block 12 and the bushing 11 are both made of brass to ensure magnetic circuit isolation.

[0024] A coil 13 is installed above the threaded block 12. The coil 13 is vertically sleeved on the cylinder of the bushing 11, and a magnetic coating 19 is filled between the coil 13 and the threaded block 12. The coil 13 is sleeved with a magnetic ring 16 on the outside. The magnetic ring 16 consists of two permanent magnets 16-1 and two magnetic conductors 16-2. The magnetic conductors 16-2 have a threaded hole 16-3 in the middle, and are provided with a left adjustment screw 15 and a right adjustment screw 14 to facilitate the adjustment of the magnetic circuit air gap. The magnetic ring 16 is connected to the valve body 1 through a screw 18. The magnetic ring 16 is protected by a cover 17 on the outside, and a cover seal ring 20 is provided between the cover 17 and the valve body 1 to achieve sealing.

[0025] The utility model provides a novel servo valve principle structure, which integrates the traditional baffle, elastic support and armature into an integrated structure, uses a bushing 11 for sealing, greatly improves the sealing reliability, reduces the design wall thickness of the support 9, reduces the output demand for the torque motor, and realizes the miniaturization design of the torque motor. At the same time, a single coil 13 is arranged vertically to reduce the coil skeleton, effectively increase the winding volume of the coil 13, and greatly improve the output capacity of the torque motor. The magnetic ring 16 is provided with a left adjustment screw 15 and a right adjustment screw 14, which greatly improves the convenience of air gap adjustment.

Claims

1. Nozzle flapper servo valve, characterized by: The servo valve includes a valve body, on which a gasket and a support are installed, the gasket and the support are sleeved on a supporting baffle, and the gasket and the support are fixed to the valve body using screws; the bushing wraps the support and the gasket to form a whole, and a sealing ring is provided at the contact position between the bushing and the gasket; the upper and lower surfaces of the support are all oil static pressure.

2. The nozzle flapper servo valve according to claim 1, characterized in that: A threaded block is provided above the bushing, and the threaded block fixes the bushing on the valve body. Both the threaded block and the bushing are made of brass.

3. The nozzle flapper servo valve according to claim 1, characterized in that: The servo valve is also provided with an oil inlet nozzle and an oil return nozzle, which are located on both sides of the extended part of the support baffle. The oil from the two nozzles directly acts on the support baffle. By giving a command signal, the distance from the support baffle part to the two nozzles is changed, and the pressure of the output oil port is changed to realize the servo valve control.

4. The nozzle flapper servo valve according to claim 1, characterized in that: The servo valve is also provided with a thread block and a coil, which are sequentially sleeved on the support baffle, the coil is installed above the thread block, the coil is vertically sleeved on the bushing cylinder, and a magnetic coating is filled between the coil and the thread block.

5. The nozzle flapper servo valve according to claim 4, characterized in that: The coil is covered with a magnetic ring outside, which consists of two permanent magnets and two magnetic conductors. A threaded hole is opened in the middle of the magnetic conductor, and a left adjusting screw and a right adjusting screw are arranged inside to adjust the air gap of the magnetic circuit.

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