阅读说明：本技术 一种基于闭环控制的恒定力加载模拟装置及力加载方法 (Constant force loading simulation device and force loading method based on closed-loop control ) 是由 钟亮 邓建军 王金凤 唐雪松 秦红 范旭波 于 2020-05-15 设计创作，主要内容包括：本发明涉及设备疲劳试验技术领域,尤其涉及一种基于闭环控制的恒定力加载模拟装置及力加载方法,包括扭矩显示仪表和工控机；工控机的控制信号输出端依次电性连接有压控恒流源、磁滞制动器,磁滞制动器上同轴设置有扭矩传感器,扭矩传感器与所述扭矩显示仪表电性连接,扭矩显示仪表的输出端电性接入工控机的反馈信号输入端,构成一个闭环控制回路。本技术方案采用闭环控制的方式对被测物体提供所需的扭矩加载,优势在于可以在试验过程自我监控,不断提供反馈信号,以此调整加载扭矩的大小,将加载扭矩精度提高到0.5%,进一步为被测物提供连续、稳定的加载扭矩,有效的避免扭矩施加过大,超过被测物承受范围,进而导致被测物损坏的情况发生。(The invention relates to the technical field of equipment fatigue tests, in particular to a constant force loading simulation device and a force loading method based on closed-loop control, which comprise a torque display instrument and an industrial personal computer; the control signal output end of the industrial personal computer is electrically connected with a voltage-controlled constant current source and a hysteresis brake in sequence, a torque sensor is coaxially arranged on the hysteresis brake, the torque sensor is electrically connected with a torque display instrument, and the output end of the torque display instrument is electrically connected into the feedback signal input end of the industrial personal computer to form a closed-loop control loop. This technical scheme adopts closed-loop control's mode to provide required moment of torsion loading to the measured object, and the advantage lies in can constantly providing feedback signal at the self-monitoring of experimentation to this adjustment loading torque's size improves loading torque precision to 0.5%, further provides continuous, stable loading torque for the measured object, and the effectual moment of torsion of avoiding is applyed too big, exceeds the measured object and bears the scope, and then leads to the condition emergence of measured object damage.)

1. A constant force loading simulation device based on closed-loop control is characterized in that: the torque control device comprises a torque display instrument and an industrial personal computer provided with a control signal output end and a feedback signal input end; the industrial personal computer internally comprises a central processing unit, a communication module and a digital-to-analog conversion module, wherein the communication module is used as a feedback signal input end of the industrial personal computer and is electrically connected with the central processing unit, and the digital-to-analog conversion module is used as a control signal output end of the industrial personal computer and is electrically connected with the central processing unit; the control signal output of industrial computer has voltage-controlled constant current source, hysteresis brake in proper order electric connection, and the hysteresis brake is gone up the coaxial torque sensor that is provided with, torque sensor with torque display instrument electric connection, torque display instrument's output electric access the feedback signal input of industrial computer constitutes a closed-loop control circuit.

2. A closed-loop-control-based constant force loading simulation apparatus as claimed in claim 1, wherein: the torque sensor is a strain gauge torque sensor comprising a strain gauge, and the strain gauge is a resistance-type metal foil.

3. A closed-loop-control-based constant force loading simulation apparatus as claimed in claim 1, wherein: and the output end of the torque display instrument is connected to the feedback signal input end of the industrial personal computer through an RS485 communication bus.

4. A constant force loading method based on closed-loop control is characterized in that: the method comprises the steps of preparing in the early stage of a test, primarily applying torque, forming a feedback signal, adjusting the applied torque and keeping the torque;

preparing at the early stage of the test: presetting a target torque value a according to the actually required loading torque of the measured object;

the preliminary applied torque: inputting the target torque value a into an industrial personal computer, outputting a control signal corresponding to the target torque value a by using the industrial personal computer, accessing the control signal into a voltage-controlled constant current source, outputting a current signal corresponding to the control signal by using the voltage-controlled constant current source, introducing the current signal into a hysteresis brake, and controlling the hysteresis brake to apply corresponding torque to the shafting rotation of a measured object according to the current signal;

the forming of the feedback signal: the torque sensor is coaxially arranged with the hysteresis brake to realize real-time monitoring of the loading torque, the torque sensor converts the measured torque into an electric signal which is linearly proportional to the torque, the electric signal is connected into the torque display instrument, the torque display instrument converts the electric signal into a digital quantity to be displayed, meanwhile, a digital signal corresponding to the digital quantity is formed in the torque display instrument, and the digital signal is used as a feedback signal and is sent to the industrial personal computer through an RS485 communication bus;

the adjustment applies a torque: after the industrial personal computer receives the feedback signal, the internal central processing unit is utilized to calculate the actual measured load torque value N_rThe difference q between the target torque value a and the target torque value a, and the industrial personal computer controls the output of the digital-to-analog conversion module according to the magnitude of the difference qThe signal is adjusted, the magnitude of the current signal output by the voltage-controlled constant current source is further adjusted, the actual output torque of the hysteresis brake is finally changed, during the period, the torque display instrument continuously feeds back signals to the industrial personal computer until the digital quantity meets the actual requirement, the industrial personal computer stops adjusting the output control signal, and the actual output torque of the hysteresis brake is kept.

5. The constant force loading method based on closed-loop control as claimed in claim 4, wherein: the process of adjusting the applied torque further comprises the step of judging whether the difference q is equal to 0 in an industrial personal computer; if q =0, the output control signal is unchanged, and the actual output torque of the hysteresis brake is continuously maintained; if q is not equal to 0, judging that q is greater than 0, if q is greater than 0, reducing the control signal output by the digital-to-analog conversion module, reducing the output current signal of the voltage-controlled constant current source, and further reducing the actual output torque of the hysteresis brake, if q is not greater than 0, increasing the output current signal of the voltage-controlled constant current source by increasing the control signal output by the digital-to-analog conversion module, and further increasing the actual output torque of the hysteresis brake until the industrial personal computer judges that q =0, and then keeping the actual output torque of the hysteresis brake.

6. The constant force loading method based on closed-loop control as claimed in claim 4, wherein: the preliminary preparation process of the test also comprises setting a maximum allowable error value Q; the process of adjusting the applied torque further comprises judging whether the absolute value of the difference value Q is less than or equal to the maximum allowable error value Q; if Q |. is not more than Q, the output control signal is unchanged, and the actual output torque of the hysteresis brake is kept continuously; if the absolute value of the difference Q is not less than or equal to the maximum allowable error value Q, judging that Q is greater than 0, if Q is greater than 0, reducing the control signal output by the digital-to-analog conversion module, reducing the current signal output by the voltage-controlled constant current source, further reducing the actual output torque of the hysteresis brake, if Q is not greater than 0, increasing the current signal output by the voltage-controlled constant current source and further increasing the actual output torque of the hysteresis brake by increasing the control signal output by the digital-to-analog conversion module until the industrial personal computer judges that Q is less than or equal to Q, and keeping the actual output torque of the hysteresis brake.

7. The constant force loading method based on closed-loop control as claimed in claim 6, wherein: the maximum allowable error value Q is set to 1N · m.

Technical Field

The invention relates to the technical field of equipment fatigue tests, in particular to a constant force loading simulation device and a force loading method based on closed-loop control.

Background

In the fields of precision machine tool, engine design, precision test instrument research and large-scale manufacturing of airplanes, ships, automobiles and the like, on-load tests such as torsion, rotating speed and the like are involved, and specific moment loads need to be set in the test process, so that the driving capability and the stability of a tested object are verified.

At present, torque loading is mainly realized by adopting an open-loop control mode, the quality of a measured object is affected due to unstable torque application in the test process, and even the torque application is too large and exceeds the bearing range of the measured object, so that the measured object is damaged. In order to avoid the condition that a tested object is damaged, a torque detection device is added on testing equipment by part of manufacturers to monitor the torque, when the torque exceeds the range, the controller stops the brake driving device, the test is stopped, and then the test is carried out again after manual fault removal. Although the method can avoid the damage of the measured object, the applied loading force can not be accurately controlled, and the retest is time-wasting after the problem occurs, thereby slowing down the working efficiency.

Disclosure of Invention

The invention aims to provide a simulation device and a method for applying constant load to a small-torque product and verifying the driving capability of a measured object, aiming at the defects of the prior art, so as to realize accurate and constant force loading.

The method is realized by the following technical scheme:

a constant force loading simulation device based on closed-loop control comprises a torque display instrument and an industrial personal computer provided with a control signal output end and a feedback signal input end; the industrial personal computer comprises a central processing unit, a communication module and a digital-to-analog conversion module, wherein the communication module is a communication peripheral interface of the industrial personal computer, the digital-to-analog conversion module is mainly used for converting a digital signal output by the central processing unit into an analog signal and transmitting the analog signal to the voltage-controlled constant current source, and the analog signal is a voltage signal. The communication module is used as a feedback signal input end of the industrial personal computer and is electrically connected with the central processing unit, and the digital-to-analog conversion module is used as a control signal output end of the industrial personal computer and is electrically connected with the central processing unit; the control signal output of industrial computer has voltage-controlled constant current source, hysteresis brake in proper order electric connection, and the hysteresis brake is gone up the coaxial torque sensor that is provided with, torque sensor with torque display instrument electric connection, torque display instrument's output electric access the feedback signal input of industrial computer constitutes a closed-loop control circuit. The industrial personal computer is a tool general name which adopts a bus structure and detects and controls a production process, electromechanical equipment and process equipment; the industrial personal computer has important computer attributes and characteristics, such as a computer mainboard, a CPU, a hard disk, a memory, peripherals and interfaces, an operating system, a control network and protocol, computing capability and a friendly human-computer interface, and is used for realizing torque target value setting, actual torque value computing, control signal output and torque signal acquisition. The hysteresis brake utilizes a hysteresis principle to generate a certain torque by controlling the input exciting current, wherein the control current and the output torque have a better linear relation; the hysteresis brake can provide smooth, stepless and adjustable torque control irrelevant to the rotating speed, has no other friction in a hysteresis brake system except for a bearing, and has the advantages of stability, reliability, high using rotating speed, low noise, long service life, low maintenance cost and the like. The voltage-controlled constant current source is used for receiving a control signal of the industrial personal computer and outputting a current signal for controlling the hysteresis brake to output corresponding torque. Torque sensors are the detection of the perception of torsional moments on various rotating or non-rotating mechanical components. The torque display instrument is used for converting the electric signal into digital quantity for display and forming a corresponding digital signal for a loading controller to collect.

The torque sensor is a strain gauge torque sensor comprising a strain gauge, the strain gauge is a resistance-type metal foil strain gauge sensor, torque measurement is carried out by adopting a strain electric measurement technology, the strain gauge is adhered to an elastic shaft to form a measurement bridge, when the elastic shaft is subjected to small deformation caused by torque, the resistance value of the bridge is changed, and the change of the resistance of the strain bridge is converted into the change of an electric signal, so that the torque measurement is realized.

And the output end of the torque display instrument is connected to the feedback signal input end of the industrial personal computer through an RS485 communication bus. The RS485 communication bus is an RS485 bus (RS-485), the RS-485 adopts balanced transmission and differential reception, so the RS-485 bus has the capability of inhibiting common mode interference, and the bus transceiver has high sensitivity and can detect the voltage as low as 200mv, so the transmission signal can be recovered beyond kilometers. Therefore, the torque display instrument is connected to the feedback signal input end of the industrial personal computer through the RS485 communication bus, so that the feedback signal is not affected by the outside, the feedback signal can smoothly reach the industrial personal computer, and the reliability of signal transmission is improved.

A constant force loading method based on closed-loop control is characterized in that: the method comprises the steps of preparing in the early stage of a test, primarily applying torque, forming a feedback signal, adjusting the applied torque and keeping the torque;

preparing at the early stage of the test: presetting a target torque value a according to the actually required loading torque of the measured object;

the preliminary applied torque: inputting the target torque value a into an industrial personal computer, outputting a control signal corresponding to the target torque value a by using the industrial personal computer, accessing the control signal into a voltage-controlled constant current source, outputting a current signal corresponding to the control signal by using the voltage-controlled constant current source, introducing the current signal into a hysteresis brake, and controlling the hysteresis brake to apply corresponding torque to the shafting rotation of a measured object according to the current signal;

the forming of the feedback signal: the torque sensor is coaxially arranged with the hysteresis brake to realize real-time monitoring of the loading torque, the torque sensor converts the measured torque into an electric signal which is linearly proportional to the torque, the electric signal is connected into the torque display instrument, the torque display instrument converts the electric signal into a digital quantity to be displayed, meanwhile, a digital signal corresponding to the digital quantity is formed in the torque display instrument, and the digital signal is used as a feedback signal and is sent to the industrial personal computer through an RS485 communication bus;

the adjustment applies a torque: after the industrial personal computer receives the feedback signal, the internal central processing unit is utilized to calculate the actual measured load torque value N_rAnd the industrial personal computer adjusts the control signal output by the digital-to-analog conversion module according to the difference q, further adjusts the magnitude of the current signal output by the voltage-controlled constant current source, and finally changes the actual output torque of the hysteresis brake.

Preferably, the process of adjusting the applied torque further comprises judging whether the difference q is equal to 0 in an industrial personal computer; if q =0, the output control signal is unchanged, and the actual output torque of the hysteresis brake is continuously maintained; if q is not equal to 0, judging that q is greater than 0, if q is greater than 0, reducing the control signal output by the digital-to-analog conversion module, reducing the output current signal of the voltage-controlled constant current source, and further reducing the actual output torque of the hysteresis brake, if q is not greater than 0, increasing the output current signal of the voltage-controlled constant current source by increasing the control signal output by the digital-to-analog conversion module, and further increasing the actual output torque of the hysteresis brake until the industrial personal computer judges that q =0, and then keeping the actual output torque of the hysteresis brake.

Preferably, the preliminary test preparation process further includes setting a maximum allowable error value Q; the process of adjusting the applied torque further comprises judging whether the absolute value of the difference value Q is less than or equal to the maximum allowable error value Q; if Q |. is not more than Q, the output control signal is unchanged, and the actual output torque of the hysteresis brake is kept continuously; if the absolute value of the difference Q is not less than or equal to the maximum allowable error value Q, judging that Q is greater than 0, if Q is greater than 0, reducing the control signal output by the digital-to-analog conversion module, reducing the current signal output by the voltage-controlled constant current source, further reducing the actual output torque of the hysteresis brake, if Q is not greater than 0, increasing the current signal output by the voltage-controlled constant current source and further increasing the actual output torque of the hysteresis brake by increasing the control signal output by the digital-to-analog conversion module until the industrial personal computer judges that Q is less than or equal to Q, and keeping the actual output torque of the hysteresis brake.

Preferably, the maximum allowable error value Q is set to 1N · m.

The beneficial effect that this technical scheme brought:

this technical scheme adopts closed-loop control's mode to provide required moment of torsion loading to the measured object, the advantage lies in can be at the self-monitoring of testing process, constantly provide feedback signal, with this size of adjustment loading moment of torsion, improve loading moment of torsion precision to 0.5%, further provide continuous, stable loading moment of torsion for the measured object, the effectual moment of torsion of avoiding is applyed oversize, exceed the measured object and bear the scope, and then the condition that leads to the measured object to damage takes place, and this technical scheme adopts automatic control, with loading moment of torsion control in the scope of bearing of measured object, need not take the measure of torque detection device control, the process of troubleshooting has also been saved, and work efficiency is improved.

Drawings

The foregoing and following detailed description of the invention will be apparent when read in conjunction with the following drawings, in which:

FIG. 1 is a schematic flow diagram of the closed loop control signal of the present invention;

FIG. 2 is a torque loading flow diagram of a basic aspect of the present invention;

FIG. 3 is a torque loading flow diagram of a preferred embodiment of the present invention.

Detailed Description

The technical solutions for achieving the objects of the present invention are further illustrated by the following specific examples, and it should be noted that the technical solutions claimed in the present invention include, but are not limited to, the following examples.