Torque motor of corrugated pipe structure for servo valve

Abstract

The invention discloses a torque motor of a corrugated pipe structure for a servo valve, and belongs to the technical field of mechanical hydraulic pressure. A first through hole is formed in the motor base; a second through hole is formed in the center of the armature; the second end of the oil pipe is connected with the oil inlet of the motor base; the first end of the jet pipe penetrates through the first through hole of the motor base and the second through hole of the armature to be connected with the first end of the jet pipe; the coil framework is mounted on cantilevers on the two sides of the armature; the magnetic pole assembly is arranged on the motor base; the first end of the jet pipe protection cover is connected with the first through hole of the motor base, and the second end extends into the second through hole of the armature; the first end of the tubular elastic element is connected with the jet pipe, and the second end of the tubular elastic element is fixedly connected with the second end of the jet pipe protection cover. The jet pipe can be more stable in reciprocating motion through auxiliary support and elasticity provided by the tubular elastic element, and then the linearity performance of the torque motor is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of mechanical hydraulics, and more particularly relates to a torque motor with a bellows structure for a servo valve. Background Art

[0002] Jet tube type electro-hydraulic servo valves are widely used in key areas such as engines, aircraft, ships, and energy. They are mainly used in servo mechanism control systems and are the core components of servo mechanism control systems.

[0003] As the operating conditions of hydraulic servo control systems become increasingly harsh, the requirements for servo valves are further increased. At present, the jet tube electro-hydraulic servo valve is limited to a certain extent by the performance of the torque motor. The torque motor mainly generates magnetic force by the coil assembly, which interacts with the magnetic pole assembly, so that the armature drives the jet tube to repeatedly deflect to complete the work. At the same time, the current installation position of the jet tube of the torque motor is not ideal, and the deflection movement of the jet tube is unstable and there is a hidden danger of failure caused by repeated movement. The resulting performance degradation caused by elastic structure fatigue will greatly affect the performance of the electro-hydraulic servo valve, and the failure of the torque motor will have serious consequences for the hydraulic system.

[0004] Currently, in the field of servo hydraulic control, the lifespan of servo valve products is not high, their performance degrades significantly with working time, and their anti-interference ability is insufficient. This is largely due to the insufficient performance of the servo valve torque motor, which creates a certain degree of hidden dangers for the hydraulic control system. Summary of the Invention

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0006] A torque motor with a bellows structure for a servo valve, comprising:

[0007] A motor base, wherein the motor base has a gantry bracket that provides elastic deformation; a first through hole is provided on the motor base; and the motor base is used to provide support;

[0008] An armature, wherein the armature is provided with cantilevers on both sides and a second through hole is provided in the center;

[0009] an oil pipe, a second end of the oil pipe being connected to the oil inlet of the motor base;

[0010] a jet tube, wherein a first end of the jet tube passes through the first through hole of the motor base, the second through hole of the armature, and is connected to the first end of the oil pipe;

[0011] A coil frame, the coil frame being mounted on the cantilevers on both sides of the armature through a center hole;

[0012] a magnetic pole assembly, the magnetic pole assembly being disposed on the motor base and containing the coil skeleton and the armature;

[0013] a jet tube protective cover, wherein a first end of the jet tube protective cover is connected to the first through hole of the motor base, and a second end of the jet tube protective cover extends into the second through hole of the armature;

[0014] A tubular elastic element, wherein a first end connecting hole of the tubular elastic element is connected to the jet tube, and a second end of the tubular elastic element is fixedly connected to a second end of the jet tube protective cover.

[0015] Furthermore, the tubular elastic element is a bellows having a wave structure.

[0016] Furthermore, the corrugated tube has 2 to 3 corrugated structures and a wall thickness of 0.1 to 0.3 mm.

[0017] Furthermore, the first end of the bellows has a small aperture, which matches the outer diameter of the jet tube; the second end of the bellows has a large aperture, which matches the second end of the jet tube protective cover, and the three are connected by welding.

[0018] Furthermore, the clearance between the inner diameter of the first end of the bellows and the outer diameter of the jet tube is 0.001 mm to 0.005 mm, and they are fixedly connected by welding after installation.

[0019] Furthermore, the inner diameter of the jet tube is close to the inner diameter of the oil pipe to ensure the flow stability of the working medium; the outer diameter of the oil pipe is smaller than the inner diameter of the first end mounting portion of the jet tube.

[0020] Furthermore, the jet tube passes through the narrow opening of the first end of the corrugated tube and is connected to the corrugated tube. When the jet tube moves, it drives the corrugated tube to deform.

[0021] Furthermore, the jet tube, the tubular elastic element and the jet tube protective cover are connected to form a sealed flow domain, and the jet tube is located in the formed sealed flow domain when moving.

[0022] Furthermore, the second end of the jet tube protective cover has a multi-layer step structure and is cooperatively connected with the bellows.

[0023] Furthermore, the coaxiality of the tubular elastic element, the jet tube, the jet tube protective cover, the oil pipe, the second through hole of the armature and the central hole axis of the motor base is 0.01 mm.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1) The torque motor with a bellows structure provided by the present invention has a simple structure and is easy to process. The jet tube can be more stable during reciprocating motion through the auxiliary support and elasticity provided by the bellows, thereby improving the linear performance of the torque motor. At the same time, it reduces structural fatigue caused by frequent reciprocating motion, increases the service life of the torque motor, and innovatively solves the problems of poor operating stability and short life of the torque motor currently used in servo valves.

[0026] 2) The bellows were introduced for the first time into the torque motor for the servo valve, providing an additional support point for the jet tube. The bellows' excellent shock absorption and bending properties improved the stability and life of the jet tube during reciprocating deflection motion, while also enhancing the overall structure's anti-interference performance when subjected to external fluctuations. This avoids the stress concentration problem and the resulting fatigue life issues that exist in the prior art, where support is provided solely by the deformation of the gantry bracket. This in turn improves the stability, linearity, and life of the torque motor.

[0027] 3) For the first time, a jet tube, a jet tube protective cover and a bellows are used to form a fluid sealing area, placing the deflected part of the jet tube in a stable flow field. Compared with the flow field around the jet tube of similar torque motors, the flow field formed by the present invention is expanded by 5 to 8 times, avoiding the interference between the jet tube and the motor base when the deflection is too large in the prior art. At the same time, the flow field around the jet tube is more stable during movement, thereby greatly reducing the reaction on the jet tube and enhancing the stability and shock resistance of the jet tube during operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] 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 description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0029] Figure 1 A schematic diagram of the overall structure of a torque motor with a bellows structure for a servo valve provided by the present invention;

[0030] Figure 2 An exploded schematic diagram of a torque motor with a bellows structure for a servo valve provided by the present invention;

[0031] Figure 3 A top view of a torque motor with a bellows structure for a servo valve provided by the present invention;

[0032] Figure 4 for Figure 3 Cross-sectional view of section AA;

[0033] Figure 5 It is a structural diagram of the motor base;

[0034] Figure 6 Schematic diagram of the explosion of the magnetic pole assembly;

[0035] In the figure: 1. Motor base; 1a. First through hole; 1b. Gantry bracket; 1c. Center hole of gantry bracket; 1d. Oil inlet; 2. Jet tube; 3. Coil skeleton; 4. Armature; 5. Pole assembly; 5a. Lower pole shoe; 5b. Permanent magnet; 5c. Upper pole shoe; 5d. Motor mounting screw; 5e. Hexagonal nut; 5f. Limit screw; 6. Oil pipe; 7. Bellows; 8. Jet tube protective cover. DETAILED DESCRIPTION

[0036] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0037] Example 1

[0038] refer to Figure 1-6 , a torque motor with a bellows structure for a servo valve, comprising:

[0039] The motor base 1 has a gantry bracket 1b that provides elastic deformation; the motor base 1 is provided with a first through hole 1a; the motor base 1 is used to provide support;

[0040] An armature 4, with cantilevers provided on both sides of the armature 4 and a second through hole provided in the center;

[0041] The oil pipe 6 has a second end connected to the oil inlet 1d of the motor base 1;

[0042] A jet tube 2, the first end of which passes through the first through hole 1a of the motor base 1 and the second through hole of the armature 4 and is connected to the first end of the oil pipe 6;

[0043] The coil frame 3 is mounted on the cantilevered arms on both sides of the armature 4 through the center hole;

[0044] The magnetic pole assembly 5 is arranged on the motor base 1 and includes the coil skeleton 3 and the armature 4;

[0045] A jet tube protective cover 8, wherein a first end of the jet tube protective cover 8 is connected to the first through hole 1a of the motor base 1 and is mounted in the first through hole 1a (center hole) of the motor base 1, and a second end of the jet tube protective cover 8 extends into the second through hole of the armature 4;

[0046] The tubular elastic element has a first end connecting hole connected to the jet tube 2 , and a second end of the tubular elastic element is fixedly connected to the second end of the jet tube protective cover 8 .

[0047] In this embodiment, the tubular elastic element is preferably a corrugated tube 7 having a wave structure. Specifically, the corrugated tube 7 has 2 to 3 corrugated structures and a wall thickness of 0.1 to 0.3 mm.

[0048] The bellows 7 is preferably a metal bellows. A metal bellows is a thin-walled pipe with a corrugated shape, offering excellent bending and shock absorption properties. It serves as a compensating element to compensate for various deformations of the mechanical structure. Introducing a bellows structure at an appropriate location within the torque motor effectively addresses existing technical issues.

[0049] In this embodiment, the armature 4 is welded under the gantry bracket 1b on the upper part of the motor base 1, the jet tube 2 is installed in the center hole (second through hole) of the armature 4 through the motor base 1, the second end of the oil pipe 6 is welded to the motor base 1, and the first end of the oil pipe 6 is installed on the first end of the jet tube 2, the second end of the bellows 7 is inserted into the jet tube 2 and is connected to the jet tube protective cover 8, and the first end of the jet tube protective cover 8 is installed in the center hole (first through hole 1a) of the motor base 1.

[0050] Specifically, the center of the armature 4 has a second through hole, which is arranged in the gantry bracket 1b of the torque motor base 1, and the second through hole of the armature 4 is aligned with the gantry bracket center hole 1c of the gantry bracket 1b; the first end of the jet tube 2 passes through the through holes of the motor base 1 and the armature 4, and is arranged at the center position.

[0051] Among them, the upper end of the jet tube 2 passes through the center hole (second through hole) of the armature 4 and is fixed to the armature 4, and the jet tube 2 deflects following the deflection of the armature 4; the oil pipe 6 has good flexibility, and the connection between the oil pipe 6 and the jet tube 2 will not affect the deflection movement of the jet tube 2.

[0052] In this embodiment, the oil pipe 6 is a three-section bent pipe, whose outer diameter is smaller than the aperture of the first end of the jet tube 2. The first end of the oil pipe 6 is connected to the jet tube 2, and the second end of the oil pipe 6 is connected to the oil port of the motor base 1. The three form a jet oil circuit.

[0053] The center hole (second through hole) of the armature 4 is concentrically matched with the center hole of the gantry bracket 1b on the upper part of the motor base 1. The upper surface of the armature 4 and the lower surface of the gantry bracket 1b cooperate with each other, and the two are fixed by welding. When the armature 4 is deflected by the electromagnetic force, the gantry bracket 1b is driven to deflect. At the same time, the reaction force generated by the elastic deformation of the gantry bracket 1b supports the stable movement of the armature 4. The electromagnetic force exerted on the armature 4 and the reaction force of the gantry bracket 1b are balanced with each other.

[0054] The electromagnetic force on the armature 4 is proportional to the input current. As the input current increases, the electromagnetic force increases, which drives the deflection angle of the armature 4 to increase.

[0055] In this embodiment, the armature 4 is provided with a left cantilever and a right cantilever, and the coil frame 3 is installed on the left cantilever and the right cantilever on both sides through the center hole; the magnetic pole assembly 5 is arranged on the motor base 1, and the coil frame 3 and the armature 4 are included therein, and the left cantilever and the right cantilever of the armature 4 are located at the center position of the upper pole shoe 5c and the lower pole shoe 5a.

[0056] The coil frame 3 itself is wound with a coil, and its working principle is as follows: after power is applied, a magnetic force is generated, which interacts with the magnetic field of the magnetic pole assembly 5. Under the action of the electromagnetic force, the motor base 1 and the armature 4 are driven to deflect, and the gantry bracket 1b part of the motor base 1 is elastically deformed, further driving the jet tube 2 fixed at the center of the armature 4 to deflect, thereby causing the working medium ejected through the jet tube 2 to be sprayed to the specified position of the servo valve.

[0057] The bellows 7 selected in this embodiment has a wave structure. The connecting hole at the first end of the bellows 7 is connected to the jet tube 2, and the second end of the bellows 7 is fixedly connected to the second end of the jet tube protective cover 8. The wave structure increases the overall elasticity of the motor, so that it has a certain flexibility and elasticity for absorbing vibrations, and provides support for the jet tube 2 to restore the center position; it provides additional support when the jet tube 2 is deflected, can absorb the vibration generated during work, improve the stability and linearity of the torque motor during operation, and reduce fatigue caused by reciprocating elastic deformation, thereby increasing service life.

[0058] In this embodiment, the first end of the bellows 7 has a small aperture, which matches the outer diameter of the jet tube 2; the second end of the bellows 7 has a large aperture, which matches the second end of the jet tube protective cover 8, and the three are connected by welding.

[0059] The clearance between the inner diameter of the first end of the bellows 7 and the outer diameter of the jet tube 2 is 0.001 mm to 0.005 mm, and the connection is fixed by welding after installation.

[0060] In this embodiment, the inner diameter of the jet tube 2 is close to that of the oil pipe 6 to ensure the flow stability of the working medium; the outer diameter of the oil pipe 6 is smaller than the inner diameter of the first end mounting portion of the jet tube 2.

[0061] In this embodiment, the jet tube 2 passes through the narrow opening of the first end of the bellows 7 and is connected to the bellows 7. When the jet tube 2 moves, the bellows 7 is deformed.

[0062] In this embodiment, the jet tube 2, the tubular elastic element and the jet tube protective cover 8 are connected to form a sealed flow area. The jet tube 2 is in the formed sealed flow area when moving, and the medium fills the above area when working.

[0063] Specifically, the first end of the jet tube protective cover 8 is connected to the center hole of the motor base 1, and the above-mentioned jet tube 2, bellows 7 and jet tube protective cover 8 are connected to form a sealed flow domain. Compared with the current structure, the flow domain area around the jet tube 2 of the present invention is greatly increased, which reduces the interference of the disturbed flow field on the jet tube 2 during the movement of the jet tube 2, and avoids the interference problem between the jet tube 2 and the center hole of the motor base 1 when the deflection angle of the jet tube 2 is too large in the prior art.

[0064] In this embodiment, the second end of the jet tube protective cover 8 has a multi-layer step structure, which is connected to the bellows 7, so that it can be connected to the bellows 7 with the actual part size when there is a processing error.

[0065] Among them, the wall thickness of the main part of the jet tube protective cover 8 is 1mm~3mm, and the upper end has a multi-layer step design, and the wall thickness of each step is 0.2mm~0.5mm. It is connected with the bellows 7 according to the actual part size.

[0066] In this embodiment, the coaxiality of the tubular elastic element, the jet tube 2 , the jet tube protective cover 8 , the oil pipe 6 , the second through hole of the armature 4 and the axis of the central hole of the motor base 1 is 0.01 mm.

[0067] In this embodiment, the magnetic pole assembly 5 includes a lower pole shoe 5a, a permanent magnet 5b, an upper pole shoe 5c, a motor mounting screw 5d, a hexagonal nut 5e, and a limit screw 5f. The permanent magnet 5b is disposed between the upper pole shoe 5c and the lower pole shoe 5a and is fixedly connected to the motor base 1 via the motor mounting screw 5d. The limit screw 5f passes through the upper pole shoe 5c to limit the range of motion of the armature 4.

[0068] The left and right cantilevers on both sides of the armature 4 are provided with a coil frame 3, on which a coil is wound. The whole is inside the cavity formed by the magnetic pole assembly 5. The top surface of the armature 4 is connected to the lower end surface of the gantry bracket 1b of the motor base 1, and the center holes of the two are aligned and connected.

[0069] The present invention provides a torque motor with a bellows structure for a servo valve, and its working principle is as follows:

[0070] When current is input to the coil set on the armature, due to the electromagnetic effect, the magnetic field generated by the coil interacts with the magnetic field formed by the magnetic pole assembly, driving the armature to deflect within the design range, and further driving the jet tube fixed on the armature to deflect. At the same time, the deflection of the armature synchronously drives the deformation of the gantry bracket on the motor base. The reaction force generated by the deformation is balanced with the electromagnetic force exerted on the armature, causing the jet tube to move to the specified position and be fixed, and further allowing the ejected oil to reach the specified position.

[0071] Among them, the flexibility and elasticity generated by the bellows absorb external factors such as impact and vibration that the part motor is subjected to during operation, and at the same time provide additional support force for the jet tube, so that the jet tube can remain stable during movement, and avoid the fatigue life problem caused by stress concentration caused by the existing technology that only the support force is provided by the deformation of the gantry bracket, thereby increasing the life and linearity of the torque motor.

[0072] Ultimately, the torque motor achieves smooth motion, high linearity, strong anti-interference ability and long service life during operation.

[0073] Compared with the existing technology, the present invention can avoid the performance problems such as unstable movement caused by the deformation of a single elastic structure, susceptibility to fatigue and short life, etc., introduces a bellows to provide additional support for the jet tube, and introduces a jet tube protective cover to provide a stable flow field, thereby increasing the stability and reliability of the overall torque motor, and solving the problems of the current torque motor being susceptible to interference, short life and poor performance.

[0074] The above fully describes the technical solution of the present invention. It should be noted that the specific implementation of the present invention is not limited to the above description. All technical solutions formed by ordinary technicians in this field using equivalent or equivalent transformations in structure, method or function based on the spirit of the present invention fall within the scope of protection of the present invention.

Claims

1. A torque motor with a bellows structure for a servo valve, characterized in that: include: A motor base, wherein the motor base has a gantry bracket that provides elastic deformation; a first through hole is provided on the motor base; and the motor base is used to provide support; An armature, wherein the armature is provided with cantilevers on both sides and a second through hole is provided in the center; an oil pipe, a second end of the oil pipe being connected to the oil inlet of the motor base; a jet tube, wherein a first end of the jet tube passes through the first through hole of the motor base, the second through hole of the armature, and is connected to the first end of the oil pipe; A coil frame, the coil frame being mounted on the cantilevers on both sides of the armature through a center hole; a magnetic pole assembly, the magnetic pole assembly being disposed on the motor base and containing the coil skeleton and the armature; a jet tube protective cover, wherein a first end of the jet tube protective cover is connected to the first through hole of the motor base, and a second end of the jet tube protective cover extends into the second through hole of the armature; A tubular elastic element, wherein a first end connecting hole of the tubular elastic element is connected to the jet tube, and a second end of the tubular elastic element is fixedly connected to a second end of the jet tube protective cover.

2. The torque motor with a bellows structure for a servo valve according to claim 1, characterized in that: The tubular elastic element is a bellows with a wave structure.

3. The torque motor with a bellows structure for a servo valve according to claim 2, characterized in that: The corrugated pipe has 2 to 3 corrugated structures and a wall thickness of 0.1 to 0.3 mm.

4. The torque motor with a bellows structure for a servo valve according to claim 3, characterized in that: The first end of the bellows has a small aperture, which matches the outer diameter of the jet tube; the second end of the bellows has a large aperture, which matches the second end of the jet tube protective cover, and the three are connected by welding.

5. The torque motor with a bellows structure for a servo valve according to claim 4, characterized in that: The clearance between the inner diameter of the first end of the bellows and the outer diameter of the jet tube is 0.001 mm to 0.005 mm, and the connection is fixed by welding after installation.

6. The torque motor with a bellows structure for a servo valve according to claim 4, characterized in that: The inner diameter of the jet tube is close to that of the oil pipe to ensure the flow stability of the working medium; the outer diameter of the oil pipe is smaller than the inner diameter of the first end mounting portion of the jet tube.

7. The torque motor with a bellows structure for a servo valve according to claim 4, characterized in that: The jet tube passes through the narrow opening of the first end of the corrugated tube and is connected to the corrugated tube. When the jet tube moves, it drives the corrugated tube to deform.

8. The torque motor with a bellows structure for a servo valve according to claim 1, characterized in that: The jet tube, the tubular elastic element and the jet tube protective cover are connected to form a sealed flow domain, and the jet tube is located in the formed sealed flow domain when moving.

9. The torque motor with a bellows structure for a servo valve according to claim 1, characterized in that: The second end of the jet tube protective cover has a multi-layer step structure and is cooperatively connected with the corrugated tube.

10. The torque motor with a bellows structure for a servo valve according to claim 1, characterized in that: The coaxiality of the tubular elastic element, the jet tube, the jet tube protective cover, the oil pipe, the second through hole of the armature and the central hole axis of the motor base is 0.01 mm.

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