A fluid static pressure deep rolling cutter actual pressure closed loop regulation and axial force conversion device based on leakage flow compensation

Abstract

The application discloses a kind of based on leakage flow compensation fluid static pressure deep rolling cutter actual pressure closed-loop regulation and axial force conversion device, it is related to hydraulic deep rolling machining monitoring and control field.The device includes hydraulic pump station, pressure acquisition unit, leakage flow sensor, data processing unit and feedback control unit.Leakage flow sensor gathers the leakage flow of cutter leakage oil return channel, data processing unit calculates workpiece actual acting pressure according to pump set pressure or pump outlet measured pressure, and combines leakage flow-pressure loss model, and converts axial rolling force according to effective pressure area.Feeback control unit adjusts pump set pressure according to the deviation of actual pressure and target pressure, so that actual acting pressure stably reaches target value, improves pressure compensation precision and machining stability.

Description

Technical Field

[0001] This invention relates to the field of hydraulic system pressure monitoring technology and feedback control, specifically to a closed-loop adjustment and axial force conversion device for the actual pressure of hydrostatic deep rolling tools based on leakage flow compensation. Background Technology

[0002] Hydrostatic deep roll forming uses hydraulic pressure to drive a roll forming actuator onto the workpiece surface, thereby creating plastic deformation and residual compressive stress on the workpiece surface, improving the fatigue strength, surface quality, and service reliability of the parts. In this process, the actual hydraulic pressure acting on the workpiece and the resulting axial roll forming force are key parameters affecting machining quality and process stability.

[0003] In current deep roller burnishing processes, the burnishing pressure is typically estimated based on the hydraulic pump station's set pressure or pump outlet pressure, and then the axial force is calculated according to the effective pressure-bearing area. However, the pump set pressure is not equivalent to the actual effective pressure acting on the workpiece. After the hydraulic oil enters the burnishing tool, it is affected by factors such as leakage within the tool's internal clearance, seal wear, changes in oil viscosity, and changes in structural clearances, resulting in an actual operating pressure lower than the pump set pressure. If the pump set pressure is still directly used to calculate the axial burnishing pressure, it is easy to overestimate the pressure, which in turn affects the judgment of burnishing quality and the control of process parameters.

[0004] Furthermore, existing deep rolling devices lack an active compensation mechanism for internal tool leakage in terms of hydraulic pressure control. During operation, gap leakage inevitably occurs within the hydraulic chamber of the tool, and the leakage amount dynamically fluctuates with changes in tool wear, sealing condition, and hydraulic oil temperature. Due to the structural characteristics of the rolling tool, after the hydraulic oil enters the hydraulic chamber through the tool inlet, a portion of the hydraulic oil supplied to the tool leaks back through the internal gaps, directly reflecting the pressure loss state within the tool. Currently, there is no device to quantitatively characterize the pressure decay within the tool by collecting this leakage flow rate and use it as a feedback signal to adjust the pump set pressure in real time. This results in the effective hydraulic pressure acting on the workpiece remaining consistently low and undetectable under conditions such as increased tool wear or rising oil temperature, leading to inaccurate axial rolling pressure and affecting the consistency and stability of machining quality.

[0005] Meanwhile, existing devices mostly remain at the stage of indirect measurement of pressure or axial force, lacking a closed-loop feedback mechanism to automatically adjust the pump set pressure based on the actual applied pressure. When tool leakage fluctuates with wear, oil temperature, or changes in operating conditions, the system cannot compensate for the actual pressure loss in a timely manner, causing the rolling pressure acting on the workpiece to deviate from the target value, affecting machining consistency and stability. Therefore, it is necessary to propose a device that can calculate the actual applied pressure using tool leakage flow and perform closed-loop adjustment based on the deviation between the actual pressure and the target pressure.

[0006] Furthermore, the axial rolling force Fz, determined by the product of the actual applied pressure Pact and the effective pressure-bearing area Aeff, is a core parameter characterizing the strength of the deep rolling process, directly affecting the depth of the plastic deformation layer and the distribution of residual compressive stress in the workpiece. However, existing devices, on the one hand, use the pump set pressure instead of the actual applied pressure, leading to a systematic overestimation of Fz; on the other hand, the determination of the effective pressure-bearing area Aeff lacks calibration correction, approximating it only with the geometric area of ​​the ball head or empirical values, failing to reflect the actual impact of the ball seat structure and sealing condition on the hydraulic application area. The combination of these two factors further amplifies the axial rolling force conversion error, failing to meet the requirements of precise axial force control in the precision deep rolling process. Summary of the Invention

[0007] The purpose of this invention is to provide a closed-loop adjustment device for actual pressure and axial force conversion of hydrostatic deep rolling tools based on leakage flow compensation, so as to solve the problems in the prior art that directly equates the pump set pressure or pump outlet pressure with the actual working pressure of the workpiece, resulting in inaccurate calculation of axial rolling force and the inability to compensate for actual pressure loss in real time according to changes in tool leakage.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a closed-loop adjustment device for actual pressure and axial force conversion of hydrostatic deep rolling cutters based on leakage flow compensation, comprising a pressure acquisition unit, a leakage flow sensor, a data processing unit, and a feedback control unit.

[0009] The pressure acquisition unit is used to acquire the set pressure of the hydraulic pump station or the measured pressure at the pump outlet; the leakage flow sensor is installed at the leakage return oil channel, leakage collection pipeline or leakage outlet of the rolling cutter, and is used to acquire the leakage flow formed by leakage in the internal gap of the rolling cutter in real time; the data processing unit is connected to the pressure acquisition unit and the leakage flow sensor, and is used to calculate the effective hydraulic pressure actually acting on the workpiece based on the pressure input value and leakage flow, and further convert it into real-time axial rolling pressure; the feedback control unit is connected to the data processing unit and the hydraulic pump station, proportional pressure regulating valve or servo pump controller, and is used to adjust the set pressure of the pump according to the deviation between the actual pressure and the target pressure.

[0010] Furthermore, the data processing unit calculates the pressure loss caused by leakage within the tool's internal clearance using a leakage flow-pressure loss model, and subtracts the leakage pressure loss and the comprehensive correction pressure loss based on the pressure input value to obtain the effective hydraulic pressure actually acting on the workpiece. The actual acting pressure is calculated using the following formula:

[0011]

[0012] in, This indicates the effective hydraulic pressure actually acting on the workpiece. This indicates the pressure input value, which is either the pump set pressure or the actual measured pressure at the pump outlet. This indicates the tool leakage flow rate collected by the leakage flow sensor. This represents the leakage pressure loss calculated from the leakage flow rate. This represents the overall corrected pressure loss obtained from the calibration experiment.

[0013] Furthermore, the real-time axial rolling force is calculated using the following formula:

[0014]

[0015] in, Indicates the real-time axial rolling force. This indicates the effective pressure area of ​​the rolling tool.

[0016] Furthermore, the data processing unit equates the internal clearance leakage channel of the rolling tool to a circular leakage channel and calculates the leakage pressure loss using the following formula:

[0017]

[0018] in, Indicates the dynamic viscosity of hydraulic oil. Indicates the equivalent leakage path length. This indicates the diameter of the equivalent leakage channel.

[0019] Furthermore, the feedback control unit generates a feedback pressure regulation signal based on the deviation between the effective hydraulic pressure actually acting on the workpiece and the target hydraulic pressure, where the pressure deviation is:

[0020]

[0021] in, Indicates pressure deviation. Indicates the target hydraulic pressure. When... When the deviation exceeds the preset allowable deviation, the feedback control unit increases the set pressure of the hydraulic pump station, proportional pressure regulating valve, or servo pump controller; when When the pressure is within the preset allowable deviation range, maintain the current set pressure; when When the actual pressure is less than the negative value of the preset allowable deviation, the set pressure is reduced or a pressure stabilization control signal is output to stabilize the actual working pressure within the target pressure range.

[0022] Compared with existing technologies, this invention no longer directly uses the pump set pressure as the actual rolling pressure. Instead, it calculates the leakage pressure loss by collecting the tool leakage flow rate to obtain an effective hydraulic pressure that more closely approximates the actual stress state of the workpiece, and further converts this into axial rolling force. Simultaneously, this invention uses a feedback control unit to adjust the pump set pressure based on the deviation between the actual applied pressure and the target pressure, achieving closed-loop compensation of the actual pressure. This improves the pressure control accuracy, axial force conversion accuracy, and process stability during deep rolling. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0024] Figure 1 This is a schematic diagram of the actual pressure calculation and closed-loop regulation process based on leakage flow compensation provided in an embodiment of the present invention;

[0025] Figure 2 This is a schematic front view of the actual pressure closed-loop regulation and axial force conversion device provided in an embodiment of the present invention;

[0026] Figure 3 This is a top view schematic diagram of the overall structure of the actual pressure closed-loop regulation and axial force conversion device provided in an embodiment of the present invention;

[0027] Figure 4 This is an equivalent schematic diagram of the internal clearance leakage channel of the rolling tool provided in the embodiment of the present invention, which is equivalent to a circular leakage channel.

[0028] Explanation of reference numerals in the attached figures:

[0029] 1. Headstock; 2. Spindle chuck; 3. Tailstock chuck; 4. Turret; 5. Roller cutter holder; 6. Ball end; 7. Leakage flow sensor; 8. Hydraulic hose; 9. Hydraulic pump station; 10. Pressure acquisition unit; 13. Pressure acquisition and feedback control signal line; 14. Flow signal line. Detailed Implementation

[0030] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0031] As attached Figure 1 As shown:

[0032] Example 1:

[0033] This invention provides a closed-loop adjustment device for actual pressure and axial force conversion of hydrostatic deep rolling tools based on leakage flow compensation, comprising a pressure acquisition unit, a leakage flow sensor, a data processing unit and a feedback control unit;

[0034] The pressure acquisition unit is used to acquire the set pressure of the pump or the measured pressure at the pump outlet of the hydraulic pump station, and transmits the set pressure of the pump or the measured pressure at the pump outlet as the pressure input value to the data processing unit.

[0035] The leakage flow sensor is installed at the leakage return oil channel, leakage collection pipeline, or leakage outlet of the rolling cutter to collect the leakage flow rate caused by leakage in the internal gap of the rolling cutter in real time. The leakage flow rate is different from the total oil supply flow rate entering the rolling cutter and is used to reflect the pressure loss caused by leakage in the internal gap of the cutter.

[0036] The data processing unit is connected to the pressure acquisition unit and the leakage flow sensor signal, respectively, and is used to calculate the effective hydraulic pressure actually acting on the workpiece based on the pressure input value and leakage flow, and to calculate the real-time axial rolling force based on the correspondence between the effective hydraulic pressure and the effective pressure area of ​​the rolling tool.

[0037] The feedback control unit is connected to the data processing unit and the hydraulic pump station. It receives the actual operating pressure calculated by the data processing unit and compares the actual operating pressure with the target hydraulic pressure. When the actual operating pressure is lower than the target hydraulic pressure, the feedback control unit increases the set pressure of the hydraulic pump station; when the actual operating pressure reaches the allowable range of the target hydraulic pressure, it maintains the current set pressure; when the actual operating pressure is higher than the allowable range of the target hydraulic pressure, it decreases the set pressure or outputs a pressure stabilization control signal, thereby stabilizing the effective hydraulic pressure acting on the workpiece within the target hydraulic pressure range.

[0038] Based on the above structure, the data processing unit uses the pump set pressure or the actual measured pressure at the pump outlet obtained by the pressure acquisition unit as the pressure input value, and uses the tool leakage flow rate collected by the leakage flow sensor as the compensation basis to calculate the effective hydraulic pressure actually acting on the workpiece.

[0039] The actual applied pressure is calculated using the following formula:

[0040]

[0041] in, This indicates the effective hydraulic pressure actually acting on the workpiece. This indicates the pressure input value, which is either the pump set pressure or the actual measured pressure at the pump outlet. This indicates the tool leakage flow rate collected by the leakage flow sensor. This represents the leakage pressure loss calculated from the leakage flow rate. This represents the overall corrected pressure loss obtained from the calibration experiment.

[0042] Furthermore, the data processing unit equates the internal clearance leakage channel of the rolling tool to a circular leakage channel and calculates the leakage pressure loss using the following formula:

[0043]

[0044] in, Indicates the dynamic viscosity of hydraulic oil. Indicates the equivalent leakage path length. Indicates the equivalent leakage channel diameter. This indicates the tool leakage flow rate collected by the leakage flow sensor.

[0045] Furthermore, the real-time axial rolling force is calculated using the following formula:

[0046]

[0047] in, Indicates the real-time axial rolling force. This indicates the effective pressure area of ​​the rolling cutter. This indicates the effective hydraulic pressure actually applied to the workpiece.

[0048] Furthermore, the feedback control unit will input the actual applied pressure. With target hydraulic pressure The pressure deviation is determined by the following formula for comparison:

[0049]

[0050] in, Indicates pressure deviation. Indicates the target hydraulic pressure. This indicates the effective hydraulic pressure actually applied to the workpiece.

[0051] when When the deviation exceeds the preset allowable deviation, the feedback control unit increases the set pressure of the hydraulic pump station; when When the pressure is within the preset allowable deviation range, maintain the current set pressure; when When the negative value is less than the preset allowable deviation, the set pressure is reduced or a pressure stabilization control signal is output, so that the effective hydraulic pressure actually acting on the workpiece is stabilized within the target hydraulic pressure range.

[0052] Before formal processing, the device is pre-calibrated to determine the parameters required for calculating leakage pressure loss and axial force conversion.

[0053] First, place the roller burnishing cutter under no-load or standard load conditions, set different pump pressures respectively, and simultaneously collect the pressure input values. Leakage flow and actual pressure Based on the difference between the input pressure and the actual applied pressure, determine the pressure loss caused by leakage in the tool's internal clearance. In conjunction with the structural dimensions of the internal leakage channels of the rolling cutter, the equivalent leakage channel length is determined. Equivalent leakage path diameter Make corrections.

[0054] Hydraulic oil dynamic viscosity The dynamic viscosity of the hydraulic oil is determined based on the hydraulic oil type, operating oil temperature, or a preset temperature-viscosity correlation, and serves as the input parameter for calculating leakage pressure loss. For operating conditions with significant oil temperature variations, the dynamic viscosity of the hydraulic oil can be corrected in real time using the oil temperature detection value. This is to improve the accuracy of leakage pressure loss calculation.

[0055] Comprehensive correction of pressure loss Δ The calibration experiment determined the method used to compensate for the deviation between the pump's set pressure and the measured pressure at the pump outlet, local structural losses, installation errors, and other pressure losses that are difficult to model directly. After calibration, the data processing unit will process the corrected pressure. , μ and Δ Stored as preset parameters for real-time pressure compensation calculations during actual processing.

[0056] Furthermore, an external force sensor is used to measure different actual applied pressures. The lower rolling cutter applies the actual axial rolling force to the workpiece, and the actual axial rolling force is compared with the actual applied pressure. The correspondence between these relationships is used to correct the initial effective pressure area of ​​the rolling cutter, resulting in the effective pressure area used for real-time axial rolling force conversion. .

[0057] Specifically, effective pressure-bearing area The determination is divided into two steps: theoretical calculation and calibration correction. In the theoretical calculation, for ball-end hydraulic deep rolling tools, the effective area of ​​the ball end subjected to hydraulic oil is not simply the cross-sectional area of ​​the ball, but rather the projected area of ​​the ball end actually pushed by the oil within the hydraulic chamber. The theoretical calculation formula is:

[0058]

[0059] in, The diameter of the ball head, This is the half-angle of the hydraulic chamber's conical surface, determined by the ball seat geometry. Or, a more common simplified expression:

[0060]

[0061] That is, the diameter of the contact circle sealed by the ball seat. Based on this, the effective projected circle area of ​​the hydraulic action is taken.

[0062] In the calibration experiment correction section, with the tool not in contact with the workpiece under no-load conditions, the tool head is placed downwards against a pressure sensor (or force platform) with a known range, and different pump pressures are applied. Synchronous recording (Leakage compensated) and sensor measured force ,but:

[0063]

[0064] Take the mean (or regression slope) of multiple sets of data, correct the theoretical initial values, and obtain the final value used for conversion. .

[0065] To further illustrate the leakage flow compensation and pump set pressure correction process, 5MPa, 10MPa, 15MPa, 20MPa, and 25MPa were selected as the target actual operating pressure points. The leakage pressure loss was calculated based on the leakage flow rate collected by the leakage flow sensor, and the pump set pressure required to achieve the target actual operating pressure was calculated by combining the comprehensive correction pressure loss. The calculation results are shown in Table 1.

[0066] 5 106.5 5.00 0.725 4.185 89.1 0.815 5.89 0.783 10 213.0 10.00 1.050 8.746 186.3 1.254 11.39 1.141 15 319.5 15.00 1.375 13.213 281.4 1.787 17.03 1.507 20 426.0 20.00 1.700 17.585 374.5 2.416 22.81 1.883 25 532.5 25.00 2.025 21.861 465.6 3.139 28.74 2.268

[0067] Table 1. Conversion data between actual operating pressure and pump set pressure considering leakage flow compensation.

[0068] During operation, the target hydraulic pressure is first set according to the processing requirements. The hydraulic pump station supplies oil to the rolling cutter according to the initial set pressure. The pressure acquisition unit collects the pump's set pressure or the actual measured pressure at the pump outlet and uses it as the pressure input value. The data is transmitted to the data processing unit; the leakage flow sensor collects the leakage flow rate in real time at the leakage return oil channel, leakage collection pipeline, or leakage outlet of the rolling tool. It is transmitted to the data processing unit via the leakage flow signal line.

[0069] The data processing unit is based on the leakage flow rate Hydraulic oil dynamic viscosity μ, equivalent leakage path length Equivalent leakage path diameter Calculate the pressure loss caused by leakage in the internal clearance of the cutting tool. Subsequently, the data processing unit uses the pressure input value. Deducting leakage pressure loss and comprehensive correction of pressure loss Δ The effective hydraulic pressure actually applied to the workpiece is obtained. .

[0070] In obtaining actual pressure Then, the data processing unit calculates based on the effective pressure area. Convert the actual applied pressure into real-time axial rolling force. The system synchronously outputs the pressure input value, leakage flow rate, actual operating pressure, and axial rolling pressure to a paperless recorder or host computer for display, recording, and storage.

[0071] At the same time, the feedback control unit will apply the actual pressure. With target hydraulic pressure Comparison. When When the hydraulic pressure is below the target allowable range, the feedback control unit outputs a feedback pressure regulating signal to the hydraulic pump station to increase the pump's set pressure to compensate for pressure loss caused by tool leakage; when When the target hydraulic pressure is within the allowable range, maintain the current set pressure; when When the hydraulic pressure exceeds the target allowable range, the pump set pressure is reduced or a pressure stabilization control signal is output. This achieves closed-loop compensation control of the actual applied pressure, keeping the rolling pressure and axial rolling pressure acting on the workpiece stable.

[0072] Example 2:

[0073] As attached Figure 1-4 As shown: This embodiment is basically the same as Embodiment 1, except that this embodiment further illustrates the arrangement of each structural component in conjunction with a lathe machining scenario.

[0074] The headstock 1 is the spindle drive unit of the lathe, which provides the rotational power for the workpiece; the spindle chuck 2 is used to clamp one end of the workpiece and drive it to rotate; the tailstock chuck 3 is used to support the other end of the workpiece to ensure the rigidity of the workpiece during the machining process; the tool turret 4 is used to install and position the rolling tool; the rolling tool shank 5 is the main body of the hydrostatic deep rolling tool; and the ball head 6 is the rolling actuator that directly contacts the surface of the workpiece.

[0075] The leakage flow sensor 7 is installed in the leakage return oil channel, leakage collection pipeline, or near the leakage outlet of the rolling cutter to collect the leakage flow rate formed by leakage in the internal gap of the rolling cutter in real time. The leakage flow sensor 7 is not used to collect the total oil supply flow rate entering the rolling cutter, but to collect the leakage flow rate inside the cutter, and transmits the leakage flow rate signal to the data processing unit through the leakage flow rate signal line 14.

[0076] Hydraulic hose 8 connects hydraulic pump station 9 to the roller burnishing tool holder 5, providing hydraulic oil to the roller burnishing tool. Hydraulic pump station 9 provides the hydraulic pressure required for roller burnishing and can adjust the pump set pressure according to the feedback pressure adjustment signal. Pressure acquisition unit 10 is located at the outlet of hydraulic pump station 9 or connected to the pressure setting terminal of hydraulic pump station 9, and is used to acquire the measured pressure at the pump outlet or the pump set pressure, and is connected to the data processing unit via pressure acquisition and feedback control signal line 13.

[0077] The data processing unit calculates the leakage pressure loss based on the pressure input value obtained by the pressure acquisition unit 10 and the leakage flow rate obtained by the leakage flow sensor 7, thereby obtaining the effective hydraulic pressure actually acting on the workpiece, and converts it into real-time axial rolling pressure based on the effective pressure-bearing area. Simultaneously, the data processing unit compares the actual applied pressure with the target hydraulic pressure. When the actual applied pressure is lower than the target pressure's allowable range, it outputs a feedback pressure regulating signal to the hydraulic pump station 9 through the pressure acquisition and feedback control signal line 13 to increase the pump's set pressure. When the actual applied pressure reaches the target pressure's allowable range, it maintains the current set pressure. When the actual applied pressure is higher than the target pressure's allowable range, it reduces the set pressure or outputs a pressure stabilization control signal.

[0078] With the above arrangement, this embodiment, without changing the original lathe main structure and the basic installation method of the rolling tool, uses the leakage flow sensor 7 to collect the tool leakage flow, and combines the pressure acquisition unit 10, data processing unit and hydraulic pump station 9 to realize the calculation of actual working pressure, conversion of axial rolling pressure and closed-loop adjustment of pump set pressure, thereby avoiding the error caused by directly equating the pump set pressure with the actual working pressure of the workpiece, and improving the pressure control accuracy and process stability of deep rolling.

[0079] Working principle: This invention acquires the set pressure of the hydraulic pump station 9 or the measured pressure at the pump outlet through the pressure acquisition unit 10, and acquires the leakage flow rate formed by leakage in the internal gap of the rolling tool through the leakage flow sensor 7. The data processing unit calculates the pressure loss caused by tool leakage based on the pressure input value and leakage flow rate, thereby obtaining the effective hydraulic pressure actually acting on the workpiece, and converts it into real-time axial rolling force based on the effective pressure area.

[0080] During machining, if the leakage inside the tool increases, the leakage flow rate will change accordingly. The data processing unit can correct the leakage pressure loss in real time based on the change in leakage flow rate, avoiding the error caused by directly calculating the axial rolling pressure using the pump's set pressure. At the same time, the feedback control unit compares the actual applied pressure with the target hydraulic pressure and adjusts the set pressure of the hydraulic pump station 9 according to the deviation between the two, so that the effective hydraulic pressure actually acting on the workpiece is stabilized within the target pressure range.

[0081] Through the above methods, without changing the main structure of the lathe and the basic installation method of the rolling tool, the present invention realizes the acquisition of tool leakage flow, calculation of actual operating pressure, conversion of axial rolling force, and closed-loop regulation of pump set pressure, which can improve the accuracy of pressure control, the reliability of axial force conversion, and the stability of the machining process in hydrostatic deep rolling.

[0082] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. For those skilled in the art, various modifications, substitutions, or equivalent changes can be made to the described embodiments without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions should not be construed as limiting the scope of the claims of the present invention, and the scope of protection of the present invention should be determined by the claims.

Claims

1. A device for closed-loop adjustment of actual pressure and conversion of axial force for hydrostatic deep rolling cutters based on leakage flow compensation, characterized in that, include, The pressure acquisition unit is used to acquire the set pressure of the pump or the measured pressure at the pump outlet of the hydraulic pump station. Leakage flow sensor, installed in the leakage return oil channel, leakage collection pipeline or leakage outlet of the rolling tool, is used to collect the leakage flow rate formed by leakage in the internal gap of the rolling tool in real time; The data processing unit is connected to the pressure acquisition unit and the leakage flow sensor signal. It is used to calculate the effective hydraulic pressure actually acting on the workpiece based on the pump set pressure or the actual measured pressure at the pump outlet and the leakage flow, and further convert it into axial rolling force. The feedback control unit is connected to the data processing unit, the hydraulic pump station, the proportional pressure regulating valve, or the servo pump controller, and is used to adjust the pump set pressure according to the deviation between the actual operating pressure and the target pressure.

2. The device for closed-loop adjustment of actual pressure and axial force conversion of hydrostatic deep rolling cutter based on leakage flow compensation as described in claim 1, characterized in that, The data processing unit is capable of performing the following operations: Based on the pump set pressure or pump outlet measured pressure obtained by the pressure acquisition unit and the leakage flow rate collected by the leakage flow sensor, a leakage flow rate-pressure loss model is established to calculate the pressure loss caused by leakage in the tool's internal clearance. The effective hydraulic pressure actually applied to the workpiece is obtained by subtracting the pressure loss from the pump set pressure or the actual measured pressure at the pump outlet. Calculate the real-time axial rolling force based on the correspondence between the effective hydraulic pressure and the effective pressure area of ​​the rolling cutter; The effective hydraulic pressure is compared with the target hydraulic pressure, and a feedback pressure regulating signal is output based on the deviation between the two to adjust the set pressure of the hydraulic pump station, proportional pressure regulating valve or servo pump controller.

3. The device for closed-loop adjustment of actual pressure and axial force conversion of hydrostatic deep rolling cutter based on leakage flow compensation according to claim 2, characterized in that, The data processing unit calculates the effective hydraulic pressure actually acting on the workpiece using the following formula. in, This indicates the effective hydraulic pressure actually acting on the workpiece. This indicates the pressure input value, which is either the pump set pressure or the actual measured pressure at the pump outlet. This indicates the tool leakage flow rate collected by the leakage flow sensor. This represents the leakage pressure loss calculated from the leakage flow rate. This represents the overall corrected pressure loss obtained from the calibration experiment; The real-time axial rolling force is calculated using the following formula: in, Indicates the real-time axial rolling force. This indicates the effective pressure area of ​​the rolling cutter. This indicates the effective hydraulic pressure actually applied to the workpiece.

4. The device for closed-loop adjustment of actual pressure and axial force conversion of hydrostatic deep rolling cutter based on leakage flow compensation according to claim 3, characterized in that, The data processing unit equates the internal clearance leakage channel of the rolling tool to a tiny circular leakage channel, and calculates the leakage pressure loss based on the leakage flow rate collected by the leakage flow sensor. The leakage pressure loss is determined by the following formula: in, This represents the leakage pressure loss calculated from the leakage flow rate. This indicates the tool leakage flow rate collected by the leakage flow sensor. Indicates the dynamic viscosity of hydraulic oil. Indicates the equivalent leakage path length. This indicates the diameter of the equivalent leakage path.

5. The device for closed-loop adjustment of actual pressure and axial force conversion of hydrostatic deep rolling cutter based on leakage flow compensation according to claim 4, characterized in that, The feedback control unit generates a feedback pressure adjustment signal based on the deviation between the effective hydraulic pressure actually applied to the workpiece and the target hydraulic pressure. The pressure deviation is determined by the following formula: in, Indicates pressure deviation. Indicates the target hydraulic pressure. This indicates the effective hydraulic pressure actually acting on the workpiece. when When the deviation exceeds the preset allowable deviation, the feedback control unit increases the set pressure of the hydraulic pump station, proportional pressure regulating valve, or servo pump controller; when When the pressure is within the preset allowable deviation range, maintain the current set pressure; when When the negative value is less than the preset allowable deviation, the set pressure is reduced or a pressure stabilization control signal is output, so that the effective hydraulic pressure actually acting on the workpiece is stabilized within the target hydraulic pressure range.

6. The device for closed-loop adjustment of actual pressure and axial force conversion of hydrostatic deep rolling cutter based on leakage flow compensation according to claim 4, characterized in that, The equivalent leakage channel length Equivalent leakage path diameter The hydraulic oil dynamic viscosity is determined through tool structure dimensions, leakage channel geometry, and pre-calibration experiments, and stored as a preset parameter in the data processing unit; Determined based on hydraulic oil type, oil temperature readings, or a preset oil temperature-viscosity relationship.

7. The device for closed-loop adjustment of actual pressure and axial force conversion of hydrostatic deep rolling cutter based on leakage flow compensation according to claim 6, characterized in that, The pre-calibration experiment includes: With the roller burnishing cutter under no-load or standard load conditions, different pump pressures were set, and the corresponding leakage flow rates were collected. and actual pressure ; According to the leakage flow Actual pressure and pressure input value Back-calculate leakage pressure loss And correct the equivalent leakage path length. Equivalent leakage path diameter ; The corrected equivalent leakage channel parameters are stored in the data processing unit for use in calculating leakage pressure loss during actual processing.

8. The device for closed-loop adjustment of actual pressure and axial force conversion of hydrostatic deep rolling cutter based on leakage flow compensation according to claim 3, characterized in that, The effective pressure-bearing area Determined through a combination of theoretical calculations and calibration experiments; The theoretical calculation determines the initial effective pressure area based on the geometry of the rolling ball, ball seat, and hydraulic action cavity. In the calibration experiment, an external force sensor was used to measure different actual applied pressures. The actual axial rolling force applied to the workpiece by the lower rolling cutter is determined by the measured actual axial rolling force and the actual applied pressure. Based on the correspondence, the initial effective pressure area is corrected to obtain the effective pressure area used for real-time axial rolling force conversion. .

9. The device for closed-loop adjustment of actual pressure and axial force conversion of hydrostatic deep rolling cutter based on leakage flow compensation according to claim 8, characterized in that, It also includes a paperless recorder, which is electrically connected to the pressure acquisition unit, leakage flow sensor and data processing unit through multiple 4-20mA input interfaces. It is used to synchronously acquire, display and store pressure input values, tool leakage flow, actual effective hydraulic pressure acting on the workpiece, target hydraulic pressure and real-time axial rolling pressure curve data over time, and communicate with the host computer through RS485 / Modbus interface. A device for closed-loop adjustment of actual pressure and axial force conversion of hydrostatic deep rolling cutter based on leakage flow compensation as described in claim 9, characterized in that, The data processing unit is a programmable logic controller (PLC). The PLC is used to acquire, filter, convert units, calculate leakage pressure loss, calculate actual operating pressure, and convert axial rolling pressure online for pressure input and leakage flow signals in real time. It outputs the actual operating pressure, real-time axial rolling pressure, and feedback pressure regulation signal to a paperless recorder, hydraulic pump station, proportional pressure regulating valve, or servo pump controller through an analog output module or digital communication interface to realize real-time display, recording, alarm, and closed-loop regulation of the actual operating pressure.

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