Constant-linear-speed and constant-pressure testing method and system for wear resistance of anchor rod drill bit for coal mine

Abstract

The invention discloses a constant-linear-speed constant-pressure testing device and method for the wear resistance of an anchor rod drill bit for a coal mine. The testing device comprises a main shaft, a grinding wheel, and a constant-linear-speed control device, a displacement sensor and a constant-pressure automatic feeding device which are connected with an upper computer, the upper computer is used for setting the grinding linear speed and the grinding pressure required by the test standard and conducting PID parameter setting. The upper computer receives the radius of the grinding wheel acquired by the displacement sensor, calculates a grinding linear speed error and issues the grinding linear speed error to the constant linear speed control device to implement PID control; based on the radius abrasion loss of the grinding wheel, the pressurization feeding amount is adjusted; and the constant-pressure automatic feeding device is used for adjusting the grinding pressure required by the test standard according to the pressurization force by taking the grinding pressure error as the input of PID control during the period of adjusting the feeding amount. According to the invention, the linear speed control precision of the grinding wheel is not lower than 1%, and the fluctuation value of the feeding force does not exceed 0.5% of a set value.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of coal mine equipment detection, and more particularly, relates to a coal mine anchor rod drill bit wear resistance constant linear velocity constant pressure test method and system. BACKGROUND

[0002] At present, the test method in the process of testing the wear resistance of the anchor rod drill bit is relatively simple, and the test conditions are not easy to control. Under the condition that the diameter of the grinding wheel is continuously reduced in the grinding process and the speed of the grinding wheel spindle is maintained constant, the linear velocity of the grinding contact point will gradually decrease, which cannot effectively meet the requirement of the test standard that the grinding contact point is tested at constant linear velocity.

[0003] At the same time, with the decrease of the diameter of the grinding wheel, the protrusion height of the abrasive particles is reduced, which leads to the decrease of the contact force between the measured piece and the grinding wheel, which cannot effectively meet the requirement of the test standard that the grinding contact point is tested at constant pressure.

[0004] The prior art fails to effectively recognize the above technical problems, and the solution remains in the open-loop control mode. During the test, when the change amount of the grinding wheel accumulates to a sufficient amount, an adjustment speed signal is sent. This speed adjustment mode is a pseudo-constant speed test mode, and the real-time linear velocity control is not realized. In addition, the prior art only adjusts the speed, and fails to recognize that the pressure between the measured piece and the grinding wheel needs to be adaptively adjusted according to the change amount of the grinding wheel. Therefore, the prior art does not fundamentally solve the technical problem of meeting the requirement of the test standard that the grinding contact point is tested at constant linear velocity and constant pressure. SUMMARY

[0005] To solve the problems in the prior art, the present application provides a coal mine anchor rod drill bit wear resistance constant linear velocity constant pressure test method, which is committed to solving the technical problem that the linear velocity of the grinding contact point decreases with the decrease of the diameter of the grinding wheel during the grinding of the grinding wheel, which does not meet the requirement of the constant linear velocity constant pressure test of the grinding contact point. The present application realizes the constant linear velocity and constant pressure of the grinding wheel through standard grinding wheel diameter automatic detection, spindle speed variable frequency control and grinding contact point linear velocity closed loop control, and combines the closed loop pneumatic constant pressure automatic feeding method, which meets the test standard requirement that the control accuracy of the linear velocity of the grinding wheel is not less than 1% and the fluctuation value of the feeding force is not more than 0.5% of the set value.

[0006] The present application adopts the following technical solution. The first aspect of the present application provides a coal mine anchor rod drill bit wear resistance constant linear velocity constant pressure test device, which comprises: an upper computer, a constant linear velocity control device, a displacement sensor, a constant pressure automatic feeding device, a spindle and a grinding wheel.

[0007] The host computer is connected with the constant linear velocity control device, displacement sensor and constant pressure automatic feeding device; used for setting the grinding line speed and grinding pressure required by the test standard and carrying out PID parameter setting;

[0008] During the test, the host computer receives the grinding wheel radius collected by the displacement sensor, calculates the grinding line speed error and sends it to the constant linear velocity control device to implement PID control, and calculates the grinding wheel radius wear and sends it to the constant pressure automatic feeding device to adjust the pressure feeding amount;

[0009] The constant pressure automatic feeding device is used to adjust the pressure amount during the adjustment, and the grinding pressure error is used as the input of the PID control to adjust the pressure amount to the grinding pressure required by the test standard.

[0010] Preferably, the constant linear velocity control device comprises a PID controller, a frequency converter, a variable frequency motor and an angular velocity sensor.

[0011] The main shaft is connected with the variable frequency motor and the grinding wheel, respectively, and under the drive of the variable frequency motor, the main shaft drives the grinding wheel to rotate at the same angular velocity, and the grinding wheel grinds the anchor rod drill bit at a controlled grinding line speed.

[0012] The PID controller is connected with the host computer and the frequency converter, respectively, and the PID controller takes the error between the real-time grinding line speed v t of the grinding wheel and the grinding line speed v ref required by the test standard as the input, and after the proportional, integral and differential links, outputs the adjustment amount u(t) and sends it to the frequency converter; the frequency converter takes the adjustment amount u(t) output by the PID controller as the input to generate the PWM drive signal for driving the variable frequency motor and sends it to the variable frequency motor.

[0013] Preferably, the angular velocity sensor is connected with the host computer; used for real-time detection of the main shaft angular velocity ω t , and the measured main shaft angular velocity ω t is sent to the host computer; the angular velocity sensor is a gyroscope, an angle encoder or a tachometer generator.

[0014] Preferably, the host computer calculates the grinding wheel radius wear by subtracting the initial grinding wheel radius from the current grinding wheel radius, takes the grinding wheel radius wear as the automatic feeding amount of the constant pressure automatic feeding device, sends it to the constant pressure automatic feeding device, and adjusts the pressure feeding amount.

[0015] Preferably, the constant pressure automatic feeding device is a pneumatic constant pressure automatic feeding device, which comprises a controller, a miniature air compressor, a servo electric cylinder, an air cylinder, a pressure reducing valve, a reversing valve, a pressure sliding pair and a supporting mechanism.

[0016] Among them, the micro air compressor, the cylinder, the pressure reducing valve and the reversing valve form a pneumatic circuit.

[0017] The second aspect of the present application provides a coal mine anchor rod drill bit wear resistance constant linear velocity constant pressure test method, comprising the following steps:

[0018] The test standard required grinding wheel grinding linear velocity and grinding pressure are set;

[0019] The spindle angular velocity, the radius of the grinding wheel and the grinding pressure are collected in real time, and the real-time grinding wheel grinding linear velocity is calculated through the conversion relationship between the angular velocity, the radius of the grinding wheel and the linear velocity;

[0020] The error between the real-time grinding wheel grinding linear velocity and the test standard required grinding wheel grinding linear velocity is taken as the input of the PID control, the signal driving the spindle is output by the PID control, and the spindle speed is corrected.

[0021] Based on the real-time collected grinding wheel radius, the grinding wheel radius wear amount is calculated and sent to the constant pressure automatic feeding device to adjust the pressure feeding amount, and the error between the real-time grinding wheel grinding pressure and the test standard required grinding wheel grinding pressure is taken as the input of the PID control, and the force adjusting amount of the constant pressure automatic feeding device is output by the PID control to correct the grinding pressure.

[0022] Preferably, the error between the real-time grinding wheel grinding linear velocity and the test standard required grinding wheel grinding linear velocity is taken as the input of the PID control, the signal driving the spindle is output by the PID control, and the spindle speed is corrected.

[0023] The upper computer receives the grinding wheel radius collected by the displacement sensor, calculates the real-time grinding linear velocity v of the grinding wheel t and the error between the test standard required grinding linear velocity v ref is sent to the PID controller, and after the proportional, integral and differential links, the adjusting amount u(t) is output and sent to the frequency converter; the frequency converter takes the adjusting amount u(t) output by the PID controller as the input to generate the PWM driving signal driving the variable frequency motor, and sends it to the variable frequency motor.

[0024] Preferably, the error between the real-time grinding wheel grinding linear velocity and the test standard required grinding wheel grinding linear velocity is taken as the input of the PID control, the signal driving the spindle is output by the PID control, and the spindle speed is corrected.

[0025] The upper computer calculates the grinding wheel radius wear amount by subtracting the current grinding wheel radius from the initial grinding wheel radius, takes the grinding wheel radius wear amount as the automatic feeding amount of the constant pressure automatic feeding device, and sends it to the constant pressure automatic feeding device to adjust the pressure feeding amount.

[0026] Preferably, the error between the real-time grinding wheel grinding pressure and the grinding wheel grinding pressure required by the test standard is taken as the input of the PID control, the force adjustment amount of the constant pressure automatic feeding device is output by the PID control, and the grinding pressure is corrected, which includes:

[0027] The host computer receives the grinding pressure collected by the pressure sensor, calculates the error between the real-time grinding pressure of the grinding wheel and the grinding pressure required by the test standard, sends the error to the PID controller, outputs the adjustment amount f(t) after the proportional, integral and differential links, and sends it to the pneumatic constant pressure automatic feeding device; the pneumatic constant pressure automatic feeding device adjusts the opening of the pressure reducing valve to adjust the pressure to the grinding pressure required by the test standard.

[0028] Preferably, the parameter setting mode of the PID control is to set according to the empirical value before testing or to dynamically adjust the adaptive PID parameters during testing.

[0029] Compared with the prior art, the beneficial effects of the present application at least include:

[0030] 1. The test method provided by the present application can continuously detect the displacement value of the grinding contact point displacement sensor during grinding, and then convert it into the grinding wheel radius to realize automatic detection of the standard grinding wheel diameter; and the real-time detected grinding wheel radius is fed back to the control system to realize real-time adjustment of the rotating speed of the frequency conversion motor and the feed amount and grinding pressure of the constant pressure automatic feeding device. On the basis of continuously adjustable grinding line speed of 15-25 m / s and continuously adjustable grinding pressure of 5-20 N, the grinding contact point line speed of the grinding wheel spindle and the grinding pressure are kept constant, which meets the test standard requirements that the control accuracy of the grinding wheel line speed is not less than 1% and the fluctuation value of the feed force is not more than 0.5% of the set value.

[0031] 2. The test method provided by the present application uses the PID control algorithm to further control the frequency converter of the frequency conversion motor, corrects the rotating speed of the grinding wheel spindle, realizes closed-loop accurate control of the grinding contact point line speed of the grinding wheel spindle, and further guarantees the constant grinding contact point line speed and grinding pressure through PID control of the feed amount and grinding pressure of the constant pressure automatic feeding device. Especially, the pressure control instruction is output to the pressure reducing valve through the PLC analog input and output module, and the accurate control of the cylinder pressure can be realized according to the monitoring output signal, which meets the test standard requirements that the fluctuation value of the feed force is not more than 0.5% of the set value. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 The coal mine anchor rod drill bit wear resistance constant line speed test method control flowchart provided according to the embodiment of the present application;

[0033] Figure 2The constant-pressure automatic feeding device provided according to the embodiment of the present application;

[0034] Figure 3 A schematic diagram of a grinding linear velocity curve when the proportional coefficient of the PID control algorithm provided according to the embodiment of the present application is 2.9;

[0035] In the figure:

[0036] 1-cylinder; 2-pressure reducing valve; 3-reversing valve. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solutions and advantages of the present application clearer, the technical solutions of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. The described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those skilled in the art without creative labor based on the spirit of the present application shall fall within the protection scope of the present application.

[0038] The embodiment 1 of the present application provides a coal mine anchor rod drill bit wear resistance constant linear velocity constant pressure test system for running a coal mine anchor rod drill bit wear resistance constant linear velocity test method, which comprises an upper computer, a constant linear velocity control device, a displacement sensor, a constant pressure automatic feeding device, a main shaft and a grinding wheel.

[0039] The constant linear velocity control device adjusts the rotation speed of the main shaft and the grinding wheel based on the change of the grinding wheel radius obtained by the displacement sensor, maintains the constant grinding linear velocity, and comprises a PID controller, a frequency converter, a variable frequency motor and an angular velocity sensor.

[0040] The main shaft is connected with the variable frequency motor and the grinding wheel respectively; specifically, under the driving of the variable frequency motor, the main shaft drives the grinding wheel to rotate at the same angular velocity, and the grinding wheel grinds the anchor rod drill bit at a controlled grinding linear velocity.

[0041] The displacement sensor is connected with the upper computer; specifically, the displacement sensor is used for real-time detection of the grinding wheel radius, and the real-time grinding wheel radius R t is sent to the upper computer; preferably but not limitedly, the displacement sensor is a non-contact or contact high-precision displacement sensor.

[0042] It is worth noting that, as one of the outstanding and essential features of the present application, the coal mine anchor rod drill bit wear resistance constant linear velocity test method uses a high-precision displacement sensor to continuously detect the position signal during grinding, converts the grinding wheel radius in real time, and realizes automatic detection of the standard grinding wheel radius.

[0043] The angular velocity sensor is connected with the host computer; specifically, the angular velocity sensor is used to detect the spindle angular velocity ω in real time t The measured spindle angular velocity ω t is sent to the host computer; preferably but not limited to, the angular velocity sensor is a gyroscope, an angle encoder or a tachogenerator.

[0044] The host computer is connected with the PID controller, the displacement sensor and the angular velocity sensor respectively; specifically, the host computer includes a control panel for setting the required grinding line speed v ref , grinding pressure f ref and PID parameter setting for the actual physical system. Preferably but not limited to, the spindle wheel line speed of the constant linear speed and constant pressure test system is continuously adjustable in the range of 15-25 m / s, the feed force is continuously adjustable in the range of 5-20 N, and both are set as the reference values of the grinding line speed and the grinding pressure on the control panel of the host computer.

[0045] More specifically, the host computer receives the shaft angular velocity from the angular velocity sensor and the real-time wheel radius R t from the displacement sensor, and the product of the two is the real-time grinding line speed v t ; the host computer subtracts the required grinding line speed v t from the real-time grinding line speed v ref to obtain the grinding line speed error, and the error signal e(t) is used as the input of the PID controller and sent to the PID controller.

[0046] And the host computer subtracts the current wheel radius from the initial wheel radius to calculate the wheel radius wear, and uses the wheel radius wear as the automatic feed amount of the constant pressure automatic feed device and sends it to the constant pressure automatic feed device to adjust the pressure feed amount.

[0047] As shown in Figure 1 , the PID controller is connected with the host computer and the frequency converter respectively; specifically, the PID controller takes the error between the real-time grinding line speed v t and the required grinding line speed v ref as the input, and after the proportional, integral and differential links, outputs the adjustment amount u(t) and sends it to the frequency converter.

[0048] More specifically, the PID controller has a built-in PID control algorithm model, which is expressed by the following formula (1):

[0049]

[0050] In the formula,

[0051] u(t) is the output of the PID control algorithm, that is, the adjustment amount issued to the frequency converter;

[0052] e(t) is the error signal, that is, the input signal of the PID control algorithm;

[0053] K p , K i and K d are non-negative and represent the coefficients of the proportional term, the integral term and the differential term respectively, which are parameterized at the host computer.

[0054] Notably, as one of the prominent and essential features of the present application, the coal mine anchor rod drill bit wear resistance constant linear velocity testing method uses a PID control algorithm, detects and counts the angular velocity of the main shaft through an angle encoder, feeds the test data back to the PID controller, and corrects the rotational speed of the variable frequency motor, thereby achieving the technical effect of closed-loop precise control.

[0055] The frequency converter is connected with the PID controller and the variable frequency motor respectively; specifically, the frequency converter takes the adjustment amount u(t) output by the PID controller as input, generates a PWM drive signal for driving the variable frequency motor, issues the PWM drive signal to the variable frequency motor, controls the rotational speed of the variable frequency motor, that is, the rotational speed of the main shaft and the grinding linear speed of the grinding wheel.

[0056] Notably, as one of the prominent and essential features of the present application, the coal mine anchor rod drill bit wear resistance constant linear velocity testing method feeds the grinding wheel radius detected by the displacement sensor in real time to the control system, controls the variable frequency motor frequency converter, realizes variable frequency control of the grinding wheel main shaft rotational speed, and ensures that the grinding contact point linear speed of the grinding wheel main shaft remains constant.

[0057] As shown in Figure 2 , the constant pressure automatic feeding device is a pneumatic constant pressure automatic feeding device, which comprises a miniature air compressor, a servo electric cylinder, a cylinder 1, a pressure reducing valve 2, a reversing valve 3, a pressurized sliding pair and a supporting mechanism; wherein the miniature air compressor, the cylinder 1, the pressure reducing valve 2 and the reversing valve 3 form a pneumatic circuit. The pressure reducing valve 2 is connected with a constant pressure automatic feeding controller, and according to the real-time grinding wheel radius R t , the feeding amount is automatically increased, and the measured piece is attached to the surface of the grinding wheel according to the set pressure by using the PID control algorithm according to the adjustment pressure.

[0058] Preferably, the pressure reducing valve 2 is a high-precision electric proportional valve.

[0059] Embodiment 1 of the present application provides a coal mine anchor rod drill bit wear resistance constant linear velocity constant pressure testing method, comprising the following steps:

[0060] Step 1: set the grinding wheel grinding line speed and grinding pressure required by the test standard, and perform PID parameter tuning on the actual physical system.

[0061] Preferably, the PID parameter tuning on the actual physical system can be parameter tuning according to empirical values, or adaptive PID parameter dynamic adjustment in subsequent steps combined with online identification.

[0062] Step 2: real-time acquisition of spindle angular velocity, grinding wheel radius and grinding pressure, calculation of real-time grinding wheel grinding line speed through the conversion relationship between angular velocity, grinding wheel radius and line speed.

[0063] Step 3: taking the error between the real-time grinding wheel grinding line speed and the grinding wheel grinding line speed required by the test standard as the input of the PID control algorithm, after the proportional, integral and differential links, outputting the adjustment amount u(t) to the driving part of the spindle. The driving part of the spindle receives the adjustment amount output by the PID control algorithm, generates a signal to drive the spindle, corrects the spindle speed, and achieves the purpose of closed-loop precise control.

[0064] Specifically, the PID control algorithm is expressed by the following formula (2):

[0065]

[0066] In the formula:

[0067] u(t) is the output of the PID control algorithm, i.e. the adjustment amount issued to the driving part;

[0068] e(t) is the error signal, i.e. the input signal of the PID control algorithm;

[0069] K p , K i and K d are non-negative and represent the coefficients of the proportional term, the integral term and the differential term respectively, for example but not limited to parameter tuning at the host computer.

[0070] Step 4: based on the radius of the grinding wheel obtained in step 2, adjusting the feed amount of the constant pressure automatic feed device, including: automatically increasing the feed amount of the constant pressure automatic feed device with the grinding wheel wear amount; and during the increase of the feed amount, taking the error between the real-time grinding pressure and the grinding pressure required by the test standard as the input of the PID control algorithm, after the proportional, integral and differential links, outputting the adjustment amount f(t) to the pressure reducing valve of the constant pressure automatic feed device, and adjusting the pressure degree to the grinding pressure required by the test standard.

[0071] It can be understood that the PID control algorithm for adjusting the grinding pressure is similar to adjusting the grinding line speed of the grinding wheel, except that the error between the real-time grinding pressure during the adjustment of the feed amount and the grinding pressure required by the test standard is taken as the input of the PID control algorithm as the grinding wheel wears.

[0072] The more profound control mechanism is that the control of adjusting the grinding line speed of the grinding wheel is derived from the change of the grinding wheel wear radius, and the change of the grinding wheel wear radius also affects the grinding pressure, so the constant-pressure automatic feed device needs to adopt double control of pressure and displacement to coordinate control, that is, the technical problem difficulty lies in the coupling relationship between the change of the pressure and the change of the line speed, and the coordinated control of the two in the application is based on a common collected change of the grinding wheel diameter, and the two are controlled by PID algorithms respectively, without paying attention to the mutual influence between the two, and taking the line speed error and the pressure error as the inputs of the two PID control algorithms respectively, so as to quickly and accurately eliminate the errors of the line speed and the grinding pressure, and achieve the purpose of implementing the test with constant line speed and constant pressure.

[0073] Embodiment 3 of the application provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, and the computer program implements the test method according to embodiment 2 when loaded into the processor.

[0074] Embodiment 4 of the application provides a computer readable storage medium, and the computer readable storage medium stores a computer program, and the computer program implements the test method according to embodiment 2 when executed by a processor.

[0075] In order to more clearly introduce the outstanding substantial features of the application and the significant progress brought to the prior art, an application example of implementing the application is introduced as follows.

[0076] The grinding line speed of 25 mm / s required by the test standard is input on the control panel of the host computer, and the PID parameters of the actual physical system are adjusted. When the proportional coefficient is small, the steady-state error of the grinding line speed is large, and the proportional coefficient is gradually increased, and the steady-state error is continuously reduced, and when the proportional coefficient reaches 2.9, as shown in Figure 3 The grinding line speed curve when the proportional coefficient is 2.9 is shown in FIG. 4, the grinding line speed of the grinding wheel spindle is kept constant at 25 mm / s, the control accuracy reaches ±1%, and the requirements of the test grinding line speed and the control accuracy are realized. The constant-pressure automatic feed device is the same, and details are not repeated.

[0077] It is worth noting that in the embodiments of the present application, "step + number" is only a kind of expression for clearly describing the specific implementation of the test method, and is not an absolute limitation on the sequence of each step.Under the guidance of the core concept of the present application, these steps are exchanged in sequence to obtain the same or similar technical effects, which all fall within the scope of the present application.

[0078] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application and not to limit them, and although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that the specific embodiments of the present application can be modified or replaced equivalently without departing from the spirit and scope of the present application, and any modification or equivalent replacement thereof should be covered within the protection scope of the claims of the present application.

Claims

1. A device for testing the wear resistance of a coal mine anchor rod drill bit with constant linear velocity and constant pressure, characterized in that, It comprises: a host computer, a constant linear velocity control device, a displacement sensor, a constant pressure automatic feeding device, a main shaft and a grinding wheel; The host computer is connected with the constant linear velocity control device, the displacement sensor and the constant pressure automatic feeding device; it is used for setting the grinding linear velocity and the grinding pressure required by the test standard and performing PID parameter setting; During the test, the host computer receives the grinding wheel radius collected by the displacement sensor, calculates the grinding linear velocity error and sends it to the constant linear velocity control device to implement PID control; And calculates the grinding wheel radius wear amount and sends it to the constant pressure automatic feeding device to adjust the pressure feeding amount; The constant pressure automatic feeding device is used for adjusting the pressure amount by taking the grinding pressure error as the input of PID control to the grinding pressure required by the test standard.

2. The constant linear velocity and constant pressure test device for the wear resistance of the coal mine anchor rod drill bit according to claim 1, characterized in that: The constant linear velocity control device comprises a PID controller, a frequency converter, a variable frequency motor and an angular velocity sensor; The main shaft is connected with the variable frequency motor and the grinding wheel respectively; under the drive of the variable frequency motor, the main shaft drives the grinding wheel to rotate at the same angular velocity, and the grinding wheel grinds the anchor rod drill bit at the controlled grinding linear velocity; The PID controller is connected with the upper computer and the frequency converter respectively, and the PID controller takes the error between the real-time grinding line speed v of the grinding wheel t required by the test standard ref as input, outputs the adjustment amount u(t) after the proportional, integral and differential links, and sends it to the frequency converter; the frequency converter takes the adjustment amount u(t) output by the PID controller as input, generates the PWM driving signal of the driving frequency conversion motor, and sends it to the frequency conversion motor.

3. The constant linear velocity and constant pressure test device for the wear resistance of the coal mine anchor rod drill bit according to claim 2, characterized in that: The angular velocity sensor is connected with the upper computer; and is used for detecting the angular velocity ω of the main shaft in real time t The measured angular velocity ω of the main shaft is transmitted to the upper computer t The angular velocity sensor is a gyroscope, an angle encoder or a speed generator.

4. The constant linear velocity and constant pressure test device for the wear resistance of the coal mine anchor rod drill bit according to any one of claims 1 to 3, characterized in that: The host computer calculates the grinding wheel radius wear amount by subtracting the initial grinding wheel radius from the current grinding wheel radius, takes the grinding wheel radius wear amount as the automatic feeding amount of the constant pressure automatic feeding device and sends it to the constant pressure automatic feeding device to adjust the pressure feeding amount.

5. The constant linear velocity and constant pressure test device for the wear resistance of the coal mine anchor rod drill bit according to claim 4, characterized in that: The constant pressure automatic feeding device is a pneumatic constant pressure automatic feeding device, which comprises a controller, a micro air compressor, a servo electric cylinder, a pneumatic cylinder (1), a pressure reducing valve (2), a reversing valve (3), a pressure sliding pair and a supporting mechanism; The micro air compressor, the pneumatic cylinder (1), the pressure reducing valve (2) and the reversing valve (3) form a pneumatic circuit.

6. A method for testing the wear resistance of a coal mine anchor rod drill bit constant linear velocity constant pressure, characterized in that, The steps include: setting the grinding linear velocity and the grinding pressure of the grinding wheel required by the test standard; collecting the angular velocity of the main shaft, the radius of the grinding wheel and the grinding pressure in real time, calculating the real-time grinding linear velocity of the grinding wheel through the conversion relationship between the angular velocity, the radius of the grinding wheel and the linear velocity; taking the error between the real-time grinding linear velocity of the grinding wheel and the grinding linear velocity of the grinding wheel required by the test standard as the input of PID control, correcting the rotating speed of the main shaft by the signal output by the PID control to drive the main shaft; Based on the real-time collected grinding wheel radius, the grinding wheel radius wear amount is calculated and sent to the constant pressure automatic feeding device to adjust the pressure feeding amount, and the error between the real-time grinding wheel grinding pressure and the grinding wheel grinding pressure required by the test standard is taken as the input of the PID control, and the force adjustment amount of the constant pressure automatic feeding device is output by the PID control to correct the grinding pressure.

7. The constant linear velocity and constant pressure test method for the wear resistance of a coal mine anchor rod drill bit according to claim 6, characterized in that: The error between the real-time grinding wheel grinding linear velocity and the grinding linear velocity required by the test standard is taken as the input of the PID control, and the signal of the driving spindle is output by the PID control to correct the spindle speed, including: The host computer receives the grinding wheel radius obtained from the displacement sensor and calculates the real-time grinding linear velocity v of the grinding wheel. t The grinding linear speed v required by the test standard ref The error between the two is sent to the PID controller, which outputs the adjustment quantity u(t) after passing through the proportional, integral, and derivative components, and then sends it to the frequency converter. The frequency converter takes the adjustment quantity u(t) output by the PID controller as input, generates a PWM drive signal to drive the variable frequency motor, and sends it to the variable frequency motor.

8. The constant linear velocity and constant pressure test method for the wear resistance of a coal mine anchor rod drill bit according to claim 6, characterized in that: The constant pressure automatic feeding device is adjusted by the grinding wheel radius wear amount, including: The host computer calculates the grinding wheel radius wear amount by subtracting the initial grinding wheel radius from the current grinding wheel radius, takes the grinding wheel radius wear amount as the automatic feeding amount of the constant pressure automatic feeding device, and sends it to the constant pressure automatic feeding device to adjust the pressure feeding amount.

9. The constant linear velocity and constant pressure test method for the wear resistance of a coal mine anchor rod drill bit according to any one of claims 6 to 8, characterized in that: The error between the real-time grinding wheel grinding pressure and the grinding pressure required by the test standard is taken as the input of the PID control, and the force adjustment amount of the constant pressure automatic feeding device is output by the PID control to correct the grinding pressure, including: The host computer receives the grinding pressure collected by the pressure sensor, calculates the error between the real-time grinding pressure of the grinding wheel and the grinding pressure required by the test standard, sends the error to the PID controller, and outputs the adjustment amount f(t) after the proportional, integral, and differential links, and sends it to the pneumatic constant pressure automatic feeding device; the pneumatic constant pressure automatic feeding device adjusts the opening degree of the pressure reducing valve to adjust the pressure to the grinding pressure required by the test standard.

10. The constant linear velocity and constant pressure test method for the wear resistance of a coal mine anchor rod drill bit according to claim 6, characterized in that: The parameter setting method of the PID control is to set the value according to experience before the test or to dynamically adjust the adaptive PID parameters during the test.

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