Precise press-fit device for interference fit parts and application method

Abstract

The invention belongs to the field of mechanical hydraulic pressure, and particularly relates to a precise press-fit device for interference fit parts and an application method. Comprising an adder, a controller, a power amplifier module, a pressure servo valve, a hydraulic cylinder, a force sensor, a force application rod, a displacement sensor, a displacement sensor signal processing module and a force sensor signal processing module. An input signal is connected with the summator and is subtracted from signals fed back by the displacement sensor signal processing module and the force sensor signal processing module to form a difference instruction, the difference instruction is resolved by the controller, the resolved instruction is amplified by the power amplifier module to form a servo valve instruction signal, and the pressure servo valve outputs linear pressure according to the instruction signal. The pressure drives the hydraulic cylinder to generate thrust, the hydraulic cylinder pushes the force application rod to punch the plug, the force sensor monitors the punching force, the displacement sensor measures the position of the plug in a non-contact mode, and displacement and force signals are fed back to the adder through the force displacement sensor signal processing module and the force sensor signal processing module respectively. Closed-loop feedback is formed; and finally, gradually-changed thrust is output and acts on the plug through the force application rod, and the plug is pressed into the corresponding position of the valve body. The debugging consistency of the servo valve is improved, the debugging efficiency is improved, interference surface scratches caused by multiple times of pressing and pulling of the jet device are avoided, and the working reliability of the jet device part is improved.

Description

Technical Field

[0001] The invention belongs to the field of mechanical hydraulics, and in particular relates to a precision press-fit device for interference-fit parts and an application method thereof. Background Art

[0002] Electro-hydraulic servo valves are precision hydraulic control components, mainly used in hydraulic servo control systems and widely used in the aerospace field. With the vigorous development of aerospace, the demand for servo valves is gradually increasing, the output efficiency of servo valves needs to be greatly improved, and the improvement of reliability is also urgent.

[0003] During the debugging process of traditional methods, the positions of the ejector, throttle cone and housing need to be tested and adjusted many times before they can be determined. All the parts on the valve need to be disassembled for each adjustment, which is a lot of work and there is also the risk of bringing in excess materials. The corresponding holes of the ejector, throttle cone and housing are interference fits. The traditional parts are usually pressed in by hammering them in, or directly pressed in by a press, which cannot be automated and accurately positioned. If they are pressed in too much during the press-fitting process, they need to be pulled out. Repeated pressing and pulling will damage the interference surface, resulting in oil leakage problems. Therefore, accurate determination of the parts position and accurate press-fitting are urgently needed. The traditional position standard between the ejector and the adjustment plate is based on the flow gain out of the ejector. According to batch production data, a large proportion of servo valves have problems such as small stability margin and easy resonance. Summary of the invention

[0004] Purpose of the present invention:

[0005] The invention overcomes the shortcomings of the existing technology and solves the problems of accurately pressing in the interference fit parts, accurately determining the position of the ejector and pressing it into place at one time, and the stability of the valve.

[0006] The technical solution of the present invention is as follows: In order to achieve the above-mentioned purpose of the invention, the present invention proposes a precision press-fitting device for interference fit parts, including an adder, a controller, a power amplifier module, a pressure servo valve, a hydraulic cylinder, a force sensor, a force application rod, a displacement sensor, a displacement sensor signal processing module, and a force sensor signal processing module;

[0007] The input signal is connected to the adder and subtracted from the signals fed back by the displacement sensor signal processing module and the force sensor signal processing module to form a difference command, which is solved by the controller. The solved command is amplified by the power amplifier module to form a servo valve command signal. The pressure servo valve outputs linear pressure according to the command signal. The pressure drives the hydraulic cylinder to generate thrust. The hydraulic cylinder pushes the force rod to punch the plug. The force sensor monitors the punching force. The displacement sensor measures the position of the plug by non-contact means. The displacement and force signals are fed back to the adder through the force displacement sensor signal processing module and the force sensor signal processing module respectively to form a closed-loop feedback; finally, a gradually changing thrust is output, which acts on the plug through the force rod to press the plug into the corresponding position of the valve body.

[0008] Furthermore, the controller adopts a PID control algorithm to perform integration processing on the displacement error signal to obtain the pressure amplitude by integration; the power amplifier module converts the pressure amplitude signal into a pulse signal of corresponding amplitude and specified frequency; the controller adopts a high-pass filter to retain the thrust peak value of the difference.

[0009] Furthermore, the hydraulic cylinder adopts a single-rod hydraulic cylinder with a spring, the pressure is passed into the rodless chamber, and the spring is arranged in the rod chamber.

[0010] On the other hand, the present invention also proposes an application method of a precision press-fit device for interference-fit parts, the purpose of which is to accurately press-fit the throttling cone and the ejector position of the servo valve to realize the pressure characteristics of the hydraulic amplifier stage of the servo valve. The part of the servo valve related to the amplifier stage consists of a left throttling cone, a left ejector, an adjustment plate, a right ejector, a valve core, and a right throttling cone. The left throttling cone and the right throttling cone are both interference-fitted with the housing hole, and the left ejector and the right ejector are both interference-fitted with the housing hole. The application method of the device of the present invention comprises the following steps:

[0011] Step S1: measuring the sizes of the throttling cone ring and the ejector, and selecting the sizes of a pair of throttling cone rings and a pair of ejectors;

[0012] Step S2: According to the flow continuity equation, calculate the initial throttling cone displacement Xv and the distance X between the ejector and the regulating plate when maintaining a constant damping ratio. f0 ;

[0013] Step S3: Improve the model for fluid simulation, bring the test data into the simulation boundary conditions, and obtain the corrected throttle cone displacement Xv and the distance X between the ejector and the regulating plate. f0 ;

[0014] Step S4: According to the displacement of the throttling cone Xv and the distance between the ejector and the regulating plate X f0 , test its damping ratio, and ensure that it is within 5% of the set value;

[0015] Step S5: Use the above steps to accumulate a large amount of data, form a database, and improve production efficiency.

[0016] Furthermore, in step S1, a microscope with a magnification of ≥200 is used to fit the throttling cone ring median diameter d m1 d m2 and ejector aperture D n1 , D n2 , measure the corresponding dimensions, the aperture difference of a pair of throttling cone rings in the middle diameter is not greater than 0.005mm, and the aperture difference of a pair of ejectors is not greater than 0.005mm;

[0017] Furthermore, in step S2, the determined left and right throttle cone displacements X are given. v1 , X v2 , calculate the distance X between the ejector and the regulating plate f0 , to meet the set damping ratio at the spray stop, including the following steps:

[0018] Step S21: Consider the median diameter d of the left and right throttle cone rings m1 d m2 And the measured size D of the left and right nozzles n1 , D n2 The measured dimensions and the flow continuity equation are listed as follows:

[0019]

[0020] p L =P1-P2

[0021] in,

[0022] C d0 is the flow coefficient at the throttling cone;

[0023] C df is the variable orifice flow coefficient;

[0024] d m1 d m2 is the middle diameter of the left and right throttling cone rings;

[0025] D n1 , D n2 is the aperture of the left and right ejector holes;

[0026] ρ is the density of hydraulic oil;

[0027] P1 and P2 are the pressures of the left and right control chambers;

[0028] X f0 is the initial spray blocking distance;

[0029] X v1 , X v2 is the displacement of the left and right throttle cones

[0030] X f is the baffle displacement;

[0031] q L is the load flow;

[0032] p L is the load pressure;

[0033] Step S22: X f Set to 0.002mm~0.005mm, calculate q L / X f and p L / X f Expression, calculate the damping ratio (q L / X f ) / (p L / X f ) is the set value, and the initial distance X between the ejector and the regulating plate is obtained. f0 ;

[0034] Step S23: Use a precision press-fit device for interference fit parts to press the left and right ejectors in, so that the distance between the left and right ejectors and the adjustment plate is X f0 ;

[0035] Step S24: Test the actual pressures P1 and P2 of the left and right control chambers.

[0036] Furthermore, in step S3, the determined X is obtained. f0 , to meet the set damping ratio at the spray stop, including the following steps:

[0037] Step S31: Setting up the model

[0038] Use 3D modeling software to build models with zero load pressure to solve q L / X f The model with zero load pressure is used to solve p L / X f , the distance between each model ejector and the regulating plate is X f0 , X f0 ±B、X f0 ±2B, X f0 ±3B, X f0 ±4B, where B is 1% of the ejector aperture Dn;

[0039] Step S32: Mesh division

[0040] The MESH component of the simulation software ANSYS WorkBench was selected to divide the mesh model. Unstructured meshing was used where the size of the ejector and the regulating plate was very small, and mesh encryption was used.

[0041] Step S33: Boundary conditions

[0042] a) Define the fluid medium as 15# aviation hydraulic oil; b) Specify the oil inlet pressure, oil outlet pressure, and control chamber pressure P1 / P2; c) Select the K-ε turbulence model; d) Select the solver; e) Initialize and set the iterative step calculation;

[0043] Step S34: Calculate Kq / Kp

[0044] Calculate multiple groups of q L / X f and p L / X f value, and find multiple groups of damping ratios (q L / X f ) / (p L / X f ), use the least squares method to fit the curve and find the X when the damping ratio is set f0 .

[0045] Furthermore, in the step S3, a precision press-fit device for interference fit parts is used to press-fit the left throttle cone and the right throttle cone respectively. v1 , X v2 The distance between the left ejector and the right ejector and the adjustment plate is X f0 , press fit once and for all; retest (q L / X f ) / (p L / X f ) value can be guaranteed to be within 5% of the set value.

[0046] Compared with the prior art, the present invention has the following beneficial effects:

[0047] (1) The problem that the traditional press-fitting of interference fit parts using hammers and press machines has poor positioning accuracy and is easy to damage the interference surface has been solved. A precision press-fitting device for interference fit parts has been invented, which can accurately and automatically realize press-fitting, filling a domestic gap;

[0048] (2) Invented a precision press-fit device for interference-fit parts, which solved the problem of repeated press-fit between the throttle cone and the ejector and the housing hole in the servo valve, and achieved automated positioning;

[0049] (3) A method for determining the displacement of the throttle cone and the distance between the ejector and the regulating plate is invented. For each valve's respective throttle cone and ejector parameters, the throttle cone displacement Xv and the distance Xv between the ejector and the regulating plate can be specifically calculated. f0 .

[0050] (4) Setting a certain damping ratio and debugging the servo valve using the determined damping ratio can ensure the stability margin of each servo valve and improve the one-time installation and adjustment pass rate of batch products. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 This is a schematic diagram of a precision press-fit device for interference fit parts according to an embodiment of the present invention;

[0052] Figure 2 It is a diagram of the hydraulic amplifier stage of the cone throttling electro-hydraulic servo valve according to an embodiment of the present invention;

[0053] Figure 3 The method for determining the displacement of the throttling cone and the distance between the ejector and the regulating plate according to the embodiment of the present invention is implemented in steps;

[0054] Among them, adder 1, controller 2, power amplifier module 3, pressure servo valve 4, hydraulic cylinder 5, force sensor 6, force rod 7, displacement sensor 8, displacement sensor signal processing module 9, force sensor signal processing module 10, valve body 11, plug 12, left throttling cone 13, left ejector 14, adjustment plate 15, right ejector 16, valve core 17, right throttling cone 18. DETAILED DESCRIPTION

[0055] In order to more clearly illustrate the technical solution of the embodiment of the present invention, the present invention is described in detail below in conjunction with the drawings or specific implementation cases of the specification. It should be noted that some (but not all) of the disclosed examples are shown in the drawings. In fact, many different examples can be described and these examples should not be understood as being limited to the examples set forth herein. On the contrary, these examples are described so that the positive effects of the present invention are more reflected, and any parts not detailed in the text are regarded as known techniques or conventional technical means in the art.

[0056] In the specific implementation process of the present invention, a precision press-fit device for interference fit parts is specifically designed, such as Figure 1 As shown, it includes an adder 1, a controller 2, a power amplifier module 3, a pressure servo valve 4, a hydraulic cylinder 5, a force sensor 6, a force application rod 7, a displacement sensor 8, a displacement sensor signal processing module 9, and a force sensor signal processing module 10;

[0057] The input signal is connected to the adder 1, and is subtracted from the signals fed back by the displacement sensor signal processing module 9 and the force sensor signal processing module 10 to form a difference command, which is solved by the controller 2. The solved command is amplified by the power amplifier module 3 to form a servo valve command signal. The pressure servo valve 4 outputs a linear pressure according to the command signal, and the pressure drives the hydraulic cylinder 5 to generate thrust. The hydraulic cylinder 5 pushes the force rod 7 to punch the plug. The force sensor 6 monitors the punching force. The displacement sensor 8 uses a non-contact method to measure the position of the plug. The displacement and force signals are fed back to the adder 1 through the force displacement sensor signal processing module 9 and the force sensor signal processing module 10, respectively, to form a closed-loop feedback. Finally, the gradually changing thrust is output, which acts on the plug through the force rod 7, and the plug 12 is pressed into the corresponding position of the valve body (11).

[0058] Based on the design of the above-mentioned precision press-fitting device, the controller 2 adopts a PID control algorithm to perform integration processing on the displacement error signal, and the integration obtains the pressure amplitude; the power amplifier module 3 converts the pressure amplitude signal into a pulse signal of corresponding amplitude and specified frequency; the controller adopts a high-pass filter to retain the thrust peak value of the difference; the hydraulic cylinder 5 adopts a single-rod hydraulic cylinder with a spring, the pressure is passed into the rodless cavity, and the spring is set in the rod cavity;

[0059] In the specific implementation process, the present invention also proposes an application method of a precision press-fit device for interference fit parts, the purpose of which is to accurately press-fit the throttle cone and the ejector position of the servo valve to realize the pressure characteristics of the hydraulic amplifier stage of the servo valve. The parts of the servo valve related to the amplifier stage such as Figure 2 As shown, it is composed of a left throttle cone 13, a left ejector 14, an adjusting plate 15, a right ejector 16, a valve core 17, and a right throttle cone 18. The left throttle cone 13 and the right throttle cone 18 are both interference fit with the shell hole, and the left ejector 14 and the right ejector 16 are both interference fit with the shell hole. The application method of the device of the present invention includes the following steps, such as Figure 3 As shown:

[0060] Step S1: measuring the sizes of the throttling cone ring and the ejector, and selecting the sizes of a pair of throttling cone rings and a pair of ejectors;

[0061] Step S2: According to the flow continuity equation, calculate the initial throttling cone displacement Xv and the distance X between the ejector and the regulating plate when maintaining a constant damping ratio. f0 ;

[0062] Step S3: Improve the model for fluid simulation, bring the test data into the simulation boundary conditions, and obtain the corrected throttle cone displacement Xv and the distance X between the ejector and the regulating plate. f0 ;

[0063] Step S4: According to the displacement of the throttling cone Xv and the distance between the ejector and the regulating plate X f0, test its damping ratio, and ensure that it is within 5% of the set value;

[0064] Step S5: Use the above steps to accumulate a large amount of data, form a database, and improve production efficiency.

[0065] In a specific application case, for step S1, a microscope ≥200 times is used to fit the throttling cone ring middle diameter d m1 d m2 and ejector aperture D n1 , D n2 , measure the corresponding dimensions, the aperture difference of a pair of throttling cone rings in the middle diameter is not greater than 0.005mm, and the aperture difference of a pair of ejectors is not greater than 0.005mm;

[0066] In a specific applicable case, for the step S2, the determined left and right throttle cone displacements X are given. v1 , X v2 , calculate the distance X between the ejector and the regulating plate f0 , to meet the set damping ratio at the spray stop, including the following steps:

[0067] Step S21: Considering the left and right throttling cone ring mid-diameters dm1 and dm2 and the left and right nozzle measured dimensions Dn1 and Dn2, the flow continuity equation is listed as follows:

[0068]

[0069] p L =P1-P2

[0070] in,

[0071] C d0 is the flow coefficient at the throttling cone;

[0072] C df is the variable orifice flow coefficient;

[0073] d m1 d m2 is the middle diameter of the left and right throttling cone rings;

[0074] D n1 , D n2 is the aperture of the left and right ejector holes;

[0075] ρ is the density of hydraulic oil;

[0076] P1 and P2 are the pressures of the left and right control chambers;

[0077] X f0 is the initial spray blocking distance;

[0078] X v1 , X v2is the displacement of the left and right throttle cones

[0079] X f is the baffle displacement;

[0080] q L is the load flow;

[0081] p L is the load pressure;

[0082] Step S22: X f Set to 0.002mm~0.005mm, calculate q L / X f and p L / X f Expression, calculate the damping ratio (q L / X f ) / (p L / X f ) is the set value, and the initial distance X between the ejector and the regulating plate is obtained. f0 ;

[0083] Step S23: Use a precision press-fit device for interference fit parts to press the left and right ejectors in, so that the distance between the left and right ejectors and the adjustment plate is X f0 ;

[0084] Step S24: Test the actual pressures P1 and P2 of the left and right control chambers.

[0085] In a specific applicable case, for the step S3, find the determined X f0 , to meet the set damping ratio at the spray stop, including the following steps:

[0086] Step S31: Setting up the model

[0087] Use 3D modeling software to build models with zero load pressure to solve q L / X f The model with zero load pressure is used to solve p L / X f The distance between each model ejector and the regulating plate (15) is X f0 , X f0 ±B、X f0 ±2B, X f0 ±3B, X f0 ±4B, where B is 1% of the ejector aperture Dn;

[0088] Step S32: Mesh division

[0089] The MESH component of the simulation software ANSYS WorkBench is selected to divide the mesh model, and unstructured mesh division is used in the places where the size of the ejector and the regulating plate 15 is very small, and mesh encryption is used;

[0090] Step S33: Boundary conditions

[0091] a) Define the fluid medium as 15# aviation hydraulic oil; b) Specify the oil inlet pressure, oil outlet pressure, and control chamber pressure P1 / P2; c) Select the K-ε turbulence model; d) Select the solver; e) Initialize and set the iterative step calculation;

[0092] Step S34: Calculate Kq / Kp

[0093] Calculate multiple groups of q L / X f and p L / X f value, and find multiple groups of damping ratios (q L / X f ) / (p L / X f ), use the least squares method to fit the curve and find the X when the damping ratio is set f0 .

[0094] In a specific applicable case, for the step S3, a precision press-fit device for interference fit parts is used, and the displacements of the left throttle cone 13 and the right throttle cone 18 are respectively X v1 , X v2 The distance between the left ejector 14 and the right ejector 16 and the adjustment plate 15 is X f0 , press fit once and for all; retest (q L / X f ) / (p L / X f ) value can be guaranteed to be within 5% of the set value.

[0095] The above specific implementation methods or cases are only used to explain the technical solutions of the present invention, and are not intended to limit the present application. Any parts not described in detail are deemed to be conventional technical means or common knowledge in the field. It can be understood by ordinary technicians in this field that: based on the design concept of the present application, the technical solutions recorded in the aforementioned implementation methods should be adaptively modified, or some or all of the technical features therein should be replaced by equivalents. These modifications, equivalent replacements, and adaptively improved technical solutions do not depart from the technical essence of the present invention and should all be covered within the protection scope of the present application.

Claims

1. A precision press-fit device for interference fit parts and an application method, characterized in that: It comprises an adder (1), a controller (2), a power amplifier module (3), a pressure servo valve (4), a hydraulic cylinder (5), a force sensor (6), a force application rod (7), a displacement sensor (8), a displacement sensor signal processing module (9), and a force sensor signal processing module (10); The input signal is connected to the adder (1), and is subtracted from the signals fed back by the displacement sensor signal processing module (9) and the force sensor signal processing module (10) to form a difference command, which is solved by the controller (2). The solved command is amplified by the power amplifier module (3) to form a servo valve command signal. The pressure servo valve (4) outputs a linear pressure according to the command signal, and the pressure drives the hydraulic cylinder (5) to generate thrust. The hydraulic cylinder (5) pushes the force application rod (7) to punch the plug. The force sensor (6) monitors the punching force. The displacement sensor (8) measures the position of the plug by non-contact means. The displacement and force signals are respectively fed back to the adder (1) through the force displacement sensor signal processing module (9) and the force sensor signal processing module (10) to form a closed-loop feedback. Finally, a gradually changing thrust is output, which acts on the plug through the force application rod (7) to press the plug (12) into the corresponding position of the valve body (11).

2. The device for precision press-fitting of interference fit parts and the application method according to claim 1, characterized in that: The controller (2) adopts a PID control algorithm to perform integration processing on the displacement error signal, and the integration obtains the pressure amplitude; the power amplifier module (3) converts the pressure amplitude signal into a pulse signal of corresponding amplitude and specified frequency; the controller adopts a high-pass filter to retain the thrust peak value of the difference.

3. The device for precision press-fitting of interference fit parts and the application method according to claim 1, characterized in that: The hydraulic cylinder (5) is a single-rod hydraulic cylinder with a spring, the pressure is passed into the rodless chamber, and the spring is arranged in the rod chamber.

4. An application method of the interference fit parts precision press-fit device according to any one of claims 1 to 3, characterized in that: The invention is used to realize the pressure characteristics of the hydraulic amplifier stage of the servo valve. The servo valve and the amplifier stage are composed of a left throttle cone (13), a left ejector (14), an adjusting plate (15), a right ejector (16), a valve core (17), and a right throttle cone (18). The left throttle cone (13) and the right throttle cone (18) are both interference-fitted with the housing hole, and the left ejector (14) and the right ejector (16) are both interference-fitted with the housing hole. The throttle cone and the ejector position of the servo valve are accurately pressed and fitted, and the steps are as follows: Step S1: measuring the sizes of the throttling cone ring and the ejector, and selecting the sizes of a pair of throttling cone rings and a pair of ejectors; Step S2: According to the flow continuity equation, calculate the initial throttling cone displacement Xv and the distance X between the ejector and the regulating plate when maintaining a constant damping ratio. f0 ; Step S3: Improve the model for fluid simulation, bring the test data into the simulation boundary conditions, and obtain the corrected throttle cone displacement Xv and the distance X between the ejector and the regulating plate. f0 ; Step S4: According to the displacement of the throttling cone Xv and the distance between the ejector and the regulating plate X f0 , test its damping ratio, and ensure that it is within 5% of the set value; Step S5: Use the above steps to accumulate a large amount of data, form a database, and improve production efficiency.

5. The application method of the interference fit parts precision press-fit device as claimed in claim 4, characterized in that: In step S1, use a microscope with a magnification of ≥200 to fit the throttle cone ring median diameter d m1 d m2 and ejector aperture D n1 , D n2 , measure the corresponding dimensions, the aperture difference of a pair of throttling cone rings in the middle diameter is not greater than 0.005mm, and the aperture difference of a pair of ejectors is not greater than 0.005mm.

6. The application method of the interference fit parts precision press-fit device as claimed in claim 5, characterized in that: In step S2, the determined left and right throttle cone displacements X are given. v1 , X v2 , calculate the distance X between the ejector and the regulating plate f0 , to meet the set damping ratio at the spray stop, including the following steps: Step S21: Consider the median diameter d of the left and right throttle cone rings m1 d m2 And the measured size D of the left and right nozzles n1 , D n2 The measured dimensions and the flow continuity equation are listed as follows: p L =P1-P2 in, C d0 is the flow coefficient at the throttling cone; C df is the variable orifice flow coefficient; d m1 d m2 are the middle diameters of the left and right throttle cone rings respectively; D n1 , D n2 are the apertures of the left and right ejector holes, respectively; ρ is the density of hydraulic oil; P1 and P2 are the pressures of the left and right control chambers respectively; X f0 is the initial spray blocking distance; X v1 , X v2 are the left and right throttle cone displacements, respectively; X f is the baffle displacement; q L is the load flow; p L is the load pressure; Step S22: X f Set to 0.002mm~0.005mm, calculate q L / X f and p L / X f Expression, calculate the damping ratio (q L / X f ) / (p L / X f ) is the set value, and the initial distance between the ejector and the regulating plate Xf0 is obtained; Step S23: Use a precision press-fit device for interference fit parts to press the left and right ejectors in, so that the distance between the left and right ejectors and the adjustment plate is X f0 ; Step S24: Test the actual pressures P1 and P2 of the left and right control chambers.

7. The application method of the interference fit parts precision press-fit device as claimed in claim 6, characterized in that: In step S3, the determined Xf0 is obtained to satisfy the set damping ratio at the injection stop, including the following steps: Step S31: Setting up the model Use 3D modeling software to build models with zero load pressure to solve q L / X f The model with zero load pressure is used to solve p L / X f The distance between each model ejector and the regulating plate (15) is X f0 , X f0 ±B、X f0 ±2B, X f0 ±3B, X f0 ±4B, where B is 1% of the ejector aperture Dn; Step S32: Mesh division The MESH component of the simulation software ANSYS WorkBench is selected to divide the mesh model, and unstructured mesh division is used at the places where the size of the ejector and the regulating plate (15) is very small, and mesh encryption is used; Step S33: Boundary conditions a) Define the fluid medium as 15# aviation hydraulic oil; b) Specify the oil inlet pressure, oil outlet pressure, and control chamber pressure P1 / P2; c) Select the K-ε turbulence model; d) Select the solver; e) Initialize and set the iterative step calculation; Step S34: Calculate Kq / Kp Calculate multiple groups of q L / X f and p L / X f value, and find multiple groups of damping ratios (q L / X f ) / (p L / X f ), use the least squares method to fit the curve and find the X when the damping ratio is set f0 .

8. The application method of the interference fit parts precision press-fit device as claimed in claim 7, characterized in that: In step S3, a precision press-fit device for interference fit parts is used to press-fit the left throttle cone (13) and the right throttle cone (18) by displacements of X and v1 , X v2 The distance between the left ejector (14) and the right ejector (16) and the adjustment plate (15) is X. f0 , press fit once and for all; retest (q L / X f ) / (p L / X f ) value can be guaranteed to be within 5% of the set value.

Images