CN-121973095-A - Closed-loop system and method for suppressing vibration of grinding spindle through magneto damping

CN121973095ACN 121973095 ACN121973095 ACN 121973095ACN-121973095-A

Abstract

The application relates to the technical field of grinding systems, and discloses a closed-loop system and a method for suppressing vibration of a grinding main shaft by using magneto damping, which aim to solve the problems of better suppressing vibration of the grinding main shaft and improving processing quality. The closed loop system comprises a grinding main shaft, a sensing module, a magnetic field execution module and a controller, wherein the sensing module is used for detecting the temperature value of the grinding main shaft, the magnetic field execution module is used for generating a damping magnetic field so as to restrain vibration of the grinding main shaft, the sensing module and the magnetic field execution module are electrically connected with the controller, the controller is configured to acquire the optimal value of the magnetic induction intensity of the magnetic field execution module, acquire the temperature value of the grinding main shaft at the current moment, calculate the temperature change rate at the current moment and predict the predicted temperature value after the preset time, and if the predicted temperature value is greater than or equal to a safe temperature threshold value and/or the temperature change rate is greater than or equal to an early warning rate, the magnetic induction intensity of the magnetic field execution module is controlled to be smaller than the optimal value.

Inventors

YIN TENGFEI
GAN XIAOFENG
ZHANG GUOQING

Assignees

深圳大学

Dates

Publication Date: 20260505
Application Date: 20260228

Claims (10)

1. A closed loop system for magnetically damping vibrations of a grinding spindle, comprising: Grinding the main shaft; the sensing module is used for detecting the temperature value of the grinding spindle; A magnetic field execution module for generating a damping magnetic field to suppress vibration of the grinding spindle; the sensing module and the magnetic field execution module are electrically connected with the controller, and the controller is configured to: acquiring an optimal value of the magnetic induction intensity of the magnetic field execution module, wherein the optimal value is used for restraining vibration of the grinding spindle to the greatest extent; Acquiring a temperature value of the grinding spindle at the current moment, calculating a temperature change rate at the current moment according to the temperature value at the current moment, and predicting a predicted temperature value after a preset time; if the predicted temperature value is smaller than a safety temperature threshold value and the temperature change rate is smaller than an early warning rate, controlling the magnetic induction intensity of the magnetic field execution module to be an optimal value; And if the predicted temperature value is greater than or equal to a safety temperature threshold value and/or the temperature change rate is greater than or equal to an early warning rate, controlling the magnetic induction intensity of the magnetic field execution module to be smaller than an optimal value.
2. The closed loop system of claim 1, wherein the controller is further configured to: Predicting a temperature rise value in a preset time period after the current moment by adopting a first-order discrete model; And calculating the predicted temperature value after the preset time according to the temperature rise value.
3. The closed loop system of claim 2, wherein the controller is further configured to: the predicted temperature value after the preset time after the current moment is calculated by adopting the following formula: Wherein, the Is a correction function related to the rotational speed of the grinding spindle, , For the rotational speed of the grinding spindle, A reference rotational speed for the grinding spindle; for the temperature rise value within the preset time period, Is a predicted temperature value after a preset time, As the rate of change of temperature at the present moment, For an optimal value of the magnetic induction of the magnetic field execution module, As a parameter of the model, it is possible to provide, For the rate of temperature rise of the grinding spindle caused by heat other than the heat generated by the magnetic field eddy currents, Is the duration of the preset time period.
4. A closed loop system according to any of claims 1-3, wherein the controller is further configured to: If the predicted temperature value is greater than or equal to a safe temperature threshold value and/or the temperature change rate is greater than or equal to an early warning rate, the predicted temperature value is smaller than the safe temperature threshold value and the temperature change rate is smaller than the early warning rate as a constraint, and a sub-optimal value of the magnetic induction intensity of the magnetic field execution module is calculated, wherein the sub-optimal value is smaller than the optimal value; And controlling the magnetic induction intensity of the magnetic field execution module to be the suboptimal value.
5. A closed loop system according to any of claims 1-3, wherein the sensing module is further adapted to detect an actual vibration value of the grinding spindle; The controller is further configured to: acquiring a target vibration value of the grinding spindle, and calculating an error of the actual vibration value detected by the perception module compared with the target vibration value; And calculating the magnetic induction intensity of the magnetic field execution module which reduces the error to the greatest extent through a control algorithm so as to acquire the optimal value.
6. The closed loop system of claim 5, wherein the controller is further configured to: The optimal value is calculated by the following formula: Wherein, the In order to be able to do this, , For the value of the actual vibration to be mentioned, For the value of the vibration to be the target, 、、 Are all the coefficients of the two-dimensional space, An optimal value of the magnetic induction of the module is performed for the magnetic field.
7. The closed loop system of claim 5, wherein the controller is further configured to: Establishing or identifying an approximate transfer function model G(s) of the magnetic induction intensity B-spindle vibration response V; The optimal value is calculated by the following formula: Wherein, the Is an inverse model feedforward term for counteracting the known disturbance; For feedback terms, for correcting model errors and unknown disturbances, An optimal value of the magnetic induction of the module is performed for the magnetic field.
8. The closed loop system of claim 5, wherein a filter is disposed within the controller, the controller further configured to: The optimal value is calculated by the following formula: Wherein, the As a transfer function of the filter, For the reference input signal of the filter, For an optimal value of the magnetic induction of the magnetic field execution module, Indicating a proportional relationship.
9. The closed loop system of claim 5, wherein the sensing module comprises a vibration detection device for detecting an actual vibration value of the grinding spindle and a temperature detection device for detecting a temperature value of the grinding spindle; And/or the magnetic field execution module comprises an electromagnet and a driving power supply, wherein the electromagnet is arranged on one side of the grinding main shaft along the radial direction of the grinding main shaft and is used for applying a damping magnetic field to the grinding main shaft, and the driving power supply is in ferroelectric connection with the electromagnet and is used for controlling the magnetic induction intensity of the electromagnet.
10. A method of magnetically damping vibrations of a grinding spindle comprising: Obtaining an optimal value of magnetic induction intensity applied to a grinding spindle, wherein the optimal value is used for restraining vibration of the grinding spindle to the greatest extent; Acquiring a temperature value of the grinding spindle at the current moment, calculating a temperature change rate at the current moment according to the temperature value at the current moment, and predicting a predicted temperature value after a preset time; if the predicted temperature value is smaller than a safety temperature threshold value and the temperature change rate is smaller than an early warning rate, the magnetic induction intensity applied to the grinding spindle is an optimal value; And if the predicted temperature value is greater than or equal to a safety temperature threshold value and/or the temperature change rate is greater than or equal to an early warning rate, the magnetic induction intensity applied to the grinding spindle is smaller than an optimal value.

Description

Closed-loop system and method for suppressing vibration of grinding spindle through magneto damping Technical Field The application relates to the technical field of grinding equipment, in particular to a closed-loop system and a method for restraining vibration of a grinding spindle through magnetic damping. Background In ultra-precise grinding, a grinding spindle of a grinding apparatus vibrates during rotation, and the vibration of the grinding spindle affects surface quality (e.g., roughness, waviness, etc.) and shape accuracy of a workpiece, and therefore a member for suppressing vibration of the grinding spindle is generally provided in the grinding apparatus. In the prior art, a magnetic member capable of generating magnetic field damping, such as an electromagnet, is provided in a grinding apparatus to suppress vibration of a grinding spindle by the magnetic field damping generated by the magnetic member. However, the magnetic field applied by the magnetic component to the grinding spindle can generate eddy currents in the grinding spindle (particularly the grinding spindle supported by the conductive/magnetic material), so that the grinding spindle is too high in temperature and is deformed by heating, and the grinding spindle can vibrate to influence the processing quality of a workpiece to be processed. Disclosure of Invention The application aims to provide a closed-loop system and a method for restraining vibration of a grinding main shaft by using magneto damping, which aim to solve the problems of better restraining the vibration of the grinding main shaft and improving the processing quality. In order to achieve the above purpose, the application adopts the following technical scheme: in a first aspect, the application provides a closed-loop system for suppressing vibration of a grinding spindle through magneto damping, the closed-loop system comprises the grinding spindle, a sensing module, a magnetic field execution module and a controller, wherein the sensing module is used for detecting a temperature value of the grinding spindle, the magnetic field execution module is used for generating a damping magnetic field so as to suppress vibration of the grinding spindle, the sensing module and the magnetic field execution module are electrically connected with the controller, and the controller is configured to: acquiring an optimal value of the magnetic induction intensity of the magnetic field execution module, wherein the optimal value is used for restraining vibration of the grinding main shaft to the greatest extent; acquiring a temperature value of the grinding spindle at the current moment, calculating a temperature change rate of the current moment according to the temperature value of the current moment, and predicting a predicted temperature value after a preset time; if the predicted temperature value is smaller than the safety temperature threshold value and the temperature change rate is smaller than the early warning rate, controlling the magnetic induction intensity of the magnetic field execution module to be an optimal value; if the predicted temperature value is greater than or equal to the safety temperature threshold value and/or the temperature change rate is greater than or equal to the early warning rate, controlling the magnetic induction intensity of the magnetic field execution module to be smaller than an optimal value. According to the closed loop system for suppressing vibration of the grinding spindle through the magneto damping, provided by the embodiment of the application, the temperature change rate of the grinding spindle at the current moment is calculated, the temperature change trend of the grinding spindle at the current moment can be accurately judged, and whether the temperature of the grinding spindle exceeds the safety temperature threshold value or not after the preset time is predicted through predicting the temperature change value of the grinding spindle after the preset time, so that when the predicted temperature value is smaller than the safety temperature threshold value and the temperature change rate is smaller than the early warning rate, the magnetic induction intensity of the magnetic field execution module is controlled to be the optimal value, the vibration of the grinding spindle can be suppressed to the greatest extent, the deformation caused by the overhigh temperature of the grinding spindle is avoided, and the processing quality of a workpiece is ensured. When the predicted temperature value is greater than or equal to the safe temperature threshold value and/or the temperature change rate is greater than or equal to the early warning rate, the temperature of the grinding main shaft tends to exceed the safe temperature threshold value, or the temperature of the grinding main shaft is likely to exceed the safe temperature threshold value after the preset time, and the magnetic induction intensity of the magnetic field execution modu