A brake motor with automatic braking torque compensation function

Abstract

The present invention relates to a brake motor with an automatic braking torque compensation function, wherein a brake disc is provided in the brake; an electromagnet is fixedly provided in the brake, and a brake disc is slidably provided in the brake, the brake disc is located between the brake disc and the electromagnet, and the sliding direction of the brake disc is toward the brake disc; a guide rod is fixedly provided in the brake parallel to the axial direction of the motor shaft, and the guide rod passes through the brake disc and is slidably connected to the brake disc; an armature is fixedly provided on the brake disc, and an elastic element is also provided in the brake, the elastic force of the elastic element drives the brake disc to press the brake disc; wherein the elastic unit includes a magnetorheological spring and a coil spring, the magnetorheological spring is fixedly installed in the brake, one end of the coil spring is fixedly installed on the magnetorheological spring, and the other end is fixedly installed on the brake disc. The brake motor of the present invention is particularly suitable for use in crane hoisting systems.

Description

Technical Field

[0001] The invention belongs to the technical field of brake motors, and in particular relates to a brake motor with an automatic compensation function for braking torque. Background Art

[0002] Brake motors are increasingly used in modern industry, particularly in the mechanization and automation of construction, lifting, transportation, light industry, chemical industry, woodworking, metallurgy, forging, and various machine tools. To reduce labor intensity and improve productivity, stringent requirements are being placed on various types of rapid stopping, minimizing auxiliary operating time, and ensuring accurate positioning.

[0003] The increasing demand for brake motors as main and auxiliary transmissions has also promoted their development. To meet the needs of industrial development, the motor industry has devoted decades of research and development to producing brake motors with simple and reliable structures, easy manufacturing, long maintenance cycles, simple repairs, energy saving, and economical performance.

[0004] After long-term use, the brake disc of a brake motor will experience a decrease in the spring's force against the disc due to spring degradation. Furthermore, due to wear and tear, the disc will become thinner, requiring the spring to expand further to hold the disc in place, which also reduces the spring's force. Ultimately, both factors affect braking performance, and in most cases, the combined effects of these two factors are detrimental.

[0005] Currently, to compensate for the thinning of brake discs due to wear, most engineering practices involve moving the brake disc closer to the brake disc. This approach, on the one hand, requires opening the brake motor housing and shutting down the machine; on the other hand, it fails to address the coupling issue of spring performance degradation and brake disc thinning.

[0006] Therefore, how to provide a brake motor with automatic braking torque compensation function that can compensate for the thinning of the brake disc thickness online in real time and solve the coupling problem of spring performance degradation and brake disc thickness thinning has become a technical problem that needs to be solved urgently in this field. Summary of the Invention

[0007] In order to solve the above problems, the present invention proposes a brake motor with a braking torque automatic compensation function, comprising a motor body and a brake installed on one side of the motor body;

[0008] The motor body includes a motor housing and a motor shaft, one end of the motor shaft extends out of the motor housing to connect to a load device, and the other end of the motor shaft extends out of the motor housing and is transmission-connected to a brake;

[0009] A brake disc is provided in the brake, and the brake disc is mounted on the motor shaft by a key connection;

[0010] The brake is further provided with an electromagnet fixedly and a brake disc slidably arranged therein, and the brake disc is located between the brake disc and the electromagnet, and the sliding direction of the brake disc is toward the brake disc;

[0011] A guide rod is fixedly provided in the brake parallel to the axial direction of the motor shaft, and the guide rod passes through the brake disc and is slidably connected to the brake disc;

[0012] An armature is fixedly provided on the brake disc, and an elastic element is also provided in the brake, and the elastic force of the elastic element drives the brake disc to press the brake disc;

[0013] The elastic unit includes a magnetorheological spring and a coil spring. The magnetorheological spring is fixedly installed in the brake. One end of the coil spring is fixedly installed on the magnetorheological spring, and the other end is fixedly installed on the brake disc.

[0014] Furthermore, the magnetorheological spring includes a coil support, an excitation coil, and an elastic body unit;

[0015] The coil support is fixedly mounted on the base and is provided with an inner cylinder, a middle cylinder and an outer cylinder in sequence from the inside to the outside;

[0016] The excitation coil is wound around the outside of the middle cylinder, the elastic body unit is arranged between the inner cylinder and the middle cylinder, and the top end of the middle cylinder is provided with an annular flange extending inward.

[0017] Furthermore, the elastic body unit includes a plurality of magnetorheological elastic bodies and a soft iron sheet. A soft iron sheet is arranged between two adjacent magnetorheological elastic bodies. The magnetorheological elastic body and the soft iron sheet are both annular and sleeved on the outside of the inner cylinder.

[0018] Furthermore, in the initial state, when the brake motor stops working and the power supply of the electromagnet is cut off, the magnetorheological spring is not energized.

[0019] Furthermore, a pressure column is provided on one end of the brake disc facing the mounting seat;

[0020] A pressure groove which matches the pressure column is formed on one end of the mounting seat facing the brake disc, and a pressure sensor is installed in the pressure groove.

[0021] Furthermore, a clearance groove is provided at one end of the brake disc facing the brake disc, and a distance sensor is installed in the clearance groove.

[0022] Furthermore, the dynamic control equation for adjusting the elastic coefficient of the magnetorheological spring is:

[0023]

[0024] Where F is the magnetic attraction force on the brake disc when the brake motor is in working state and the electromagnet is energized to generate magnetic force to attract the brake disc;

[0025] P is the pressure value detected by the pressure sensor when the brake motor is in working state and the electromagnet is energized to generate magnetic force to attract the brake disc;

[0026] d1 is the length of the elastic unit compressed when the brake motor is in working state and the electromagnet is energized to generate magnetic force to attract the brake disc;

[0027] k M0 is the initial elastic coefficient of the magnetorheological spring;

[0028] k SC is the elastic coefficient of the coil spring after performance attenuation;

[0029] d2 is the length of the elastic unit compressed when the brake disc is in the initial thickness state, the brake motor stops working, the power supply of the electromagnet is cut off, and the brake disc moves toward the brake disc and presses against the brake disc;

[0030] d0 is the distance value detected by the distance sensor when the brake disc is in the initial thickness state, the brake motor stops working, the power supply of the electromagnet is cut off, and the brake disc moves toward the brake disc and presses against the brake disc;

[0031] d is the distance value detected by the distance sensor when the brake disc becomes thinner, the brake motor stops working, the power supply of the electromagnet is cut off, and the brake disc moves toward the brake disc and presses against the brake disc;

[0032] k M To dynamically adjust the elastic coefficient of the magnetorheological spring;

[0033] K0 is the overall initial elastic coefficient of the elastic unit;

[0034] in,

[0035] Where K S0 is the initial elastic constant of the coil spring.

[0036] Furthermore, the brake includes a brake housing, and the brake housing is provided with an avoidance hole for the other end of the motor shaft to extend into;

[0037] The brake housing is fixedly connected to the motor housing, and a mounting cavity communicating with the avoidance hole is provided in the brake housing.

[0038] Furthermore, the brake disc includes a brake shoe for contacting the brake disc, and the brake shoe and the brake disc are detachably connected by bolts;

[0039] The hardness of the brake pad is lower than that of the brake disc, and wear is caused by the brake pad when the two come into contact with each other for braking;

[0040] The brake block is provided with a brake surface for contacting the brake disc, and the brake disc is provided with a brake surface for contacting the brake block. Both the brake surface and the brake surface are annular, and the motor shaft is located inside the inner ring of the brake surface, and the motor shaft does not contact the brake disc.

[0041] Furthermore, a mounting seat is fixedly installed in the mounting cavity, and the electromagnet is fixedly installed in the mounting seat by bolts;

[0042] A base is also fixedly mounted on the outer periphery of the lower end of the mounting seat, and the end of the guide rod is fixedly mounted on the base;

[0043] The elastic element is sleeved on the guide rod, one end of the guide rod is connected to the brake disc, and the other end of the guide rod is connected to the base.

[0044] The advantages of the present invention are:

[0045] 1. The invented brake motor with automatic braking torque compensation function can compensate for the insufficient elastic force caused by the thinning of the brake disc thickness and the degradation of spring performance online in real time, and can solve the coupling problem of spring performance degradation and thinning of the brake disc thickness.

[0046] 2. The overall elasticity of the elastic unit is altered by adjusting the elastic modulus of the magnetorheological spring. The elastic modulus of the magnetorheological spring varies with the strength of the applied magnetic field, offering a fast response speed and allowing for wide adjustment with only a small change in current.

[0047] 3. The brake disc is subject to a magnetic attraction to the right, as well as an elastic and supporting force to the left. The pressure sensor detects the reaction to this supporting force, i.e., the pressure exerted by the brake disc on the mounting seat. Consequently, when the spring rate of the coil spring decreases, the elastic force decreases, and the pressure exerted by the brake disc on the mounting seat increases. This indicates whether spring rate attenuation has occurred, as determined by the pressure value detected by the pressure sensor.

[0048] 4. As the brake disc moves toward and against the brake pad under the elastic force of the elastic element, the distance sensor detects the distance between the left end of the clearance groove and the right end of the motor shaft. Consequently, as the thickness of the brake pad decreases, the distance between the left end of the clearance groove and the right end of the motor shaft decreases. This distance value, detected by the distance sensor, indicates whether the brake pad thickness is decreasing.

[0049] 5. By adjusting the dynamic control equation of the elastic coefficient of the magnetorheological spring, a joint control relationship is established between the adjustment value of the elastic coefficient of the magnetorheological spring and the detection value of the sensor that detects the elastic coefficient attenuation of the coil spring and the thickness change of the brake disc. This can quickly and accurately adjust the elastic coefficient of the magnetorheological spring, which is conducive to dynamically compensating the elastic coefficient of the elastic unit and ensuring that the elastic force of the elastic unit on the brake disc is always greater than the threshold during braking. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present invention. The same reference symbols are used throughout the drawings to represent the same components. In the drawings:

[0051] Figure 1 This is the overall structure diagram of the brake motor;

[0052] Figure 2 It is a partial cross-sectional view of the brake motor;

[0053] Figure 3 This is a cross-sectional view of the brake motor;

[0054] Figure 4 for Figure 3 A partial enlarged view of point A in the middle. DETAILED DESCRIPTION

[0055] In order to make the purpose, technical solutions and advantages of this application more clearly understood, the present application is described and illustrated below in conjunction with the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely used to explain this application and are not intended to limit this application. Based on the embodiments provided in this application, all other embodiments obtained by those of ordinary skill in the art without making any creative efforts are within the scope of protection of this application.

[0056] like Figure 1-4 As shown, this embodiment provides a brake motor with automatic braking torque compensation function, including a motor body 100 and a brake 200 mounted on one side of the motor body 100. The motor body 100 includes a motor housing 110 and a motor shaft 120. One end of the motor shaft 120 extends from the motor housing 110 to connect to a load device for power output. The other end of the motor shaft 120 extends from the motor housing 110 and is transmission-connected to the brake 200.

[0057] The brake 200 includes a brake housing 210 having a clearance hole 211 for the other end of the motor shaft 120 to extend into. The brake housing 210 is fixedly connected to the motor housing 110 and has a mounting cavity 212 therein that communicates with the clearance hole 211.

[0058] In this embodiment, a brake disc 220 is disposed within the mounting cavity 212 and is mounted to the motor shaft 120 via a key connection, thereby securing the brake disc 220 and the motor shaft 120 relative to each other. An electromagnet 230 is also fixedly disposed within the mounting cavity 212, and a brake disc 240 is slidably disposed therein. The brake disc 240 is positioned between the brake disc 220 and the electromagnet 230, with the brake disc 240 sliding toward the brake disc 220.

[0059] A guide rod 250 is fixedly provided in the mounting cavity 212 parallel to the axial direction of the motor shaft 120 , and the guide rod 250 passes through the brake disc 240 and is slidably connected to the brake disc 240 , so that the guide rod 250 limits the brake disc 240 from rotating relative to the brake housing 210 .

[0060] An armature 241 is fixedly mounted on the brake disc 240 . An elastic element 300 is further disposed in the mounting cavity 212 . The elastic force of the elastic element 300 drives the brake disc 240 to press against the brake disc 220 .

[0061] It is understandable that the brake disc 220 and the brake disc 240 are both circular discs, and the axes of the brake disc 220 , the brake disc 240 and the motor shaft 120 coincide with each other.

[0062] In this embodiment, the brake disc 220 includes a brake block 221 for contacting the brake disc 240, and the brake block 221 and the brake disc 220 are detachably connected by bolts; the hardness of the brake block 221 is lower than that of the brake disc 240, and the brake block 221 is worn when the two are in contact and braked.

[0063] The brake block 221 is provided with a brake surface 222 for contacting the brake disc 240, and the brake disc 240 is provided with a brake surface 242 for contacting the brake block 221. The brake surfaces 222 and 242 are both annular. The motor shaft 120 is located on the inner side of the inner ring of the brake surface 222, and the motor shaft 120 does not contact the brake disc 240.

[0064] In this embodiment, a mounting seat 260 is fixedly mounted within the mounting cavity 212, and the electromagnet 230 is fixedly mounted within the mounting seat 260 via bolts. A base 261 is also fixedly mounted on the outer periphery of the lower end of the mounting seat 260. The end of the guide rod 250 is fixedly mounted to the base 261, so that the mounting seat 260, the electromagnet 230, and the guide rod 250 are all fixed relative to the brake housing 210. The elastic element 300 is sleeved on the guide rod 250, and one end of the guide rod 250 is connected to the brake disc 240, while the other end of the guide rod 250 is connected to the base 261.

[0065] It is understood that when the brake motor is in operation, the electromagnet 230 is energized to generate a magnetic force that attracts the brake disc 240, separating the brake disc 240 from the brake disc 220, thereby allowing the motor shaft 120 to rotate freely. When the brake motor stops operating, the power to the electromagnet 230 is simultaneously cut off. Under the elastic force of the elastic element 300, the brake disc 240 moves toward the brake disc 220 and presses against the brake disc 220, generating friction between the brake disc 240 and the brake disc 220. This friction quickly consumes the kinetic energy of the motor shaft 120 and the components it drives to rotate, causing the motor shaft 120 to stop rotating and achieve braking.

[0066] The conventional brake motor uses a mechanical spring to drive the brake disc 240 toward the brake disc 220 and press it against the brake disc 220. After long-term use of the brake disc 220, the performance of the spring deteriorates. According to Hooke's law, when the spring presses the brake disc 240 against the brake disc 220, the elastic force of the spring on the brake disc 220 decreases.

[0067] On the other hand, due to long-term wear of the brake, the thickness of the brake block 221 will become thinner, causing the spring to need to expand a longer length when pressing the brake disc 240 against the brake disc 220, that is, the compression of the spring becomes smaller (the compression of the spring is the largest when the electromagnet 230 is energized). According to Hooke's law, the elastic force of the spring acting on the brake disc 240 will decrease.

[0068] Based on these two reasons, the negative impact is ultimately caused by the elastic force of the spring acting on the brake disc 220 being less than the threshold.

[0069] To eliminate the aforementioned issues, the brake motor with automatic braking torque compensation in this embodiment utilizes an actively controlled spring in its elastic unit 300. Consequently, when the elastic coefficient of the elastic unit 300 decays and / or the thickness of the brake pad 221 decreases, the elastic coefficient of the elastic unit 300 is dynamically compensated. When the elastic unit 300 forces the brake disc 240 toward and against the brake disc 220, the elastic force exerted by the elastic unit 300 on the brake disc 220 is ensured to be greater than a threshold.

[0070] In this embodiment, the elastic unit 300 includes a magnetorheological spring 310 and a coil spring 320 . The magnetorheological spring 310 is fixedly mounted on the base 261 . One end of the coil spring 320 is fixedly mounted on the magnetorheological spring 310 , and the other end is fixedly mounted on the brake disc 240 .

[0071] Thus, the overall elasticity of the elastic unit 300 is changed by adjusting the elastic modulus of the magnetorheological spring 310. The elastic modulus of the magnetorheological spring 310 can change with the strength of the applied magnetic field, has a fast response speed, and can be adjusted over a wide range with only a small change in current, consuming very little energy.

[0072] Specifically, the magnetorheological spring 310 includes a coil bracket 311, an excitation coil 312 and an elastic body unit 313. The coil bracket 311 is fixedly installed on the base 261, and is provided with an inner cylinder 314, a middle cylinder 315 and an outer cylinder 316 from the inside to the outside. The excitation coil 312 is wound around the outer side 315 of the middle cylinder. The elastic body unit 313 is arranged between the inner cylinder 314 and the middle cylinder 315, and the top end of the middle cylinder 315 is extended inwardly to provide an annular flange 317 to limit the axial displacement of the elastic body unit 313 and ensure that one end of the coil spring 320 is fixedly connected to the elastic body unit 313.

[0073] The elastic body unit 313 includes several magnetorheological elastic bodies 318 and a soft iron sheet 319. A soft iron sheet 319 is positioned between two adjacent magnetorheological elastic bodies 318. Both the magnetorheological elastic bodies 318 and the soft iron sheet 319 are annular and sleeved onto the outer side of the inner cylinder 314. The soft iron sheet 319 positioned between two adjacent magnetorheological elastic bodies 318 enhances the magnetic permeability of the magnetic circuit and increases the magnetic field strength around the magnetorheological elastic bodies 318.

[0074] It is understandable that by adjusting the current in the excitation coil 312 , the elastic coefficient of the magnetorheological spring 310 can be changed, thereby achieving dynamic adjustment of the overall elastic coefficient of the elastic unit 300 .

[0075] It is worth noting that in the initial state, that is, when the elastic coefficient of the coil spring 320 has not decayed and the thickness of the brake block 221 has not become thinner, when the brake motor stops working and cuts off the power supply of the electromagnet 230, the magnetorheological spring 310 does not need to be energized, so that the magnetorheological spring 310 is at the initial elastic coefficient to save electricity. When the elastic coefficient of the coil spring 320 decays and / or the thickness of the brake block 221 becomes thinner, the magnetorheological spring 310 can be energized to adjust its elastic coefficient.

[0076] To detect whether the spring constant of the coil spring 320 has decreased, in this embodiment, a pressure column 243 is provided on the end of the brake disc 240 facing the mounting seat 260. Furthermore, a pressure groove 262 is provided on the end of the mounting seat 260 facing the brake disc 240, which is adapted to fit the pressure column 243. A pressure sensor 270 is installed in the pressure groove 262. Thus, when the electromagnet 230 is energized to generate a magnetic force that attracts the brake disc 240, the spring constant of the coil spring 320 can be detected and determined to be attenuated.

[0077] With this setting, see Figure 3 From this perspective, the brake disc 240 is subject to a rightward magnetic attraction, as well as a leftward elastic force and a supporting force. The reaction force to the supporting force, i.e., the pressure exerted by the brake disc 240 on the mounting seat 260, is detected by the pressure sensor 270. Therefore, when the spring constant of the coil spring 320 decays, the elastic force decreases, and the pressure exerted by the brake disc 240 on the mounting seat 260 increases. In other words, whether the spring constant has decayed is determined by the pressure value detected by the pressure sensor 270.

[0078] To detect whether the brake shoe 221 has become thinner, in this embodiment, a clearance groove 244 is formed on the end of the brake disc 240 facing the brake disc 220, and a distance sensor 280 is installed in the clearance groove 244. Thus, when the brake motor stops and the power to the electromagnet 230 is cut off, the brake disc 240 moves toward the brake disc 220 under the elastic force of the elastic element 300 and abuts against the brake disc 220, thereby detecting whether the brake shoe 221 has become thinner.

[0079] With this setting, see Figure 3 From this perspective, when the brake disc 240 moves toward and abuts against the brake disc 220 under the elastic force of the elastic element 300, the distance sensor 280 detects the distance between the left end surface of the clearance groove 244 and the right end surface of the motor shaft. Consequently, as the thickness of the brake shoe 221 decreases, the distance between the left end surface of the clearance groove 244 and the right end surface of the motor shaft decreases. In other words, the distance value detected by the distance sensor 280 can be used to determine whether the thickness of the brake shoe 221 has decreased.

[0080] It is worth noting that, in this embodiment, when the pressure value P detected by the pressure sensor 270 is greater than the threshold value P0, and the distance value d detected by the distance sensor 280 is not less than the threshold value d0, that is, the elastic coefficient of the coil spring 320 is attenuated, the thickness of the brake shoe 221 does not become thinner;

[0081] When the pressure value P detected by the pressure sensor 270 is not greater than the threshold value P0, and the distance value d detected by the distance sensor 280 is less than the threshold value d0, that is, the elastic coefficient of the coil spring 320 has not decayed, and the thickness of the brake shoe 221 has become thinner;

[0082] When the pressure value P detected by the pressure sensor 270 is greater than the threshold value P0, and the distance value d detected by the distance sensor 280 is less than the threshold value d0, the elastic coefficient of the coil spring 320 is attenuated, and the thickness of the brake shoe 221 is reduced.

[0083] The elastic coefficient of the dynamically adjusted magnetorheological spring 310 is:

[0084]

[0085] Wherein, F is the magnetic attraction force exerted on the brake disc 240 when the brake motor is in operation and the electromagnet 230 is energized to generate a magnetic force to attract the brake disc 240; P is the pressure value detected by the pressure sensor 270 when the brake motor is in operation and the electromagnet 230 is energized to generate a magnetic force to attract the brake disc 240; d1 is the length value of the elastic unit 300 compressed when the brake motor is in operation and the electromagnet 230 is energized to generate a magnetic force to attract the brake disc 240; k M0 k is the initial elastic coefficient of the magnetorheological spring 310; SC is the elastic coefficient of the coil spring 320 after performance attenuation; d2 is the length value of the elastic unit 300 being compressed when the brake disc 220 is in the initial thickness state, the brake motor stops working, the power supply of the electromagnet 230 is cut off, and the brake disc 240 moves toward the brake disc 220 and presses against the brake disc 220; d0 is the distance value detected by the distance sensor 280 when the brake disc 220 is in the initial thickness state, the brake motor stops working, the power supply of the electromagnet 230 is cut off, and the brake disc 240 moves toward the brake disc 220 and presses against the brake disc 220; d is the distance value detected by the distance sensor 280 when the brake disc 220 becomes thinner, the brake motor stops working, the power supply of the electromagnet 230 is cut off, and the brake disc 240 moves toward the brake disc 220 and presses against the brake disc 220; k M is the value of the elastic coefficient of the magnetorheological spring 310 that is dynamically adjusted; K0 is the initial elastic coefficient of the elastic unit 300 as a whole;

[0086] in, Where K S0 is the initial elastic coefficient of the coil spring 320.

[0087] By using the above-mentioned dynamic control equation for adjusting the elastic coefficient of the magnetorheological spring 310, a control relationship is established between the adjustment value of the elastic coefficient of the magnetorheological spring 310 and the sensor detection value for detecting the elastic coefficient attenuation of the coil spring 320 and the thickness change of the brake disc 220. This allows for rapid and precise adjustment of the elastic coefficient of the magnetorheological spring 310, which is beneficial for dynamically compensating the elastic coefficient of the elastic unit 300 and ensuring that the elastic force of the elastic unit 300 on the brake disc 240 is always greater than the threshold during braking.

[0088] It will be appreciated that the magnetorheological spring 310 of this embodiment operates in a compression mode. The elastic coefficient of the magnetorheological spring 310 varies with the strength of the applied magnetic field, that is, with the applied current. The functional relationship between the adjustment value of the elastic coefficient of the magnetorheological spring 310 and the applied current is fixed and solely dependent on the parameters of the magnetorheological spring 310. Therefore, the governing equations for the elastic coefficient of the magnetorheological spring 310 and the applied current in the compression mode are not further provided in this embodiment.

[0089] In one embodiment, the brake motor with automatic braking torque compensation function of the present invention is used in a crane hoisting system, and in the crane hoisting system, the following technical effects are achieved:

[0090] 1. The invented brake motor with automatic braking torque compensation function can compensate for the insufficient elastic force caused by the thinning of the brake disc thickness and the degradation of spring performance online in real time, and can solve the coupling problem of spring performance degradation and thinning of the brake disc thickness.

[0091] 2. The overall elasticity of the elastic unit is altered by adjusting the elastic modulus of the magnetorheological spring. The elastic modulus of the magnetorheological spring varies with the strength of the applied magnetic field, offering a fast response speed and allowing for wide adjustment with only a small change in current.

[0092] 3. The brake disc is subject to a magnetic attraction to the right, as well as an elastic and supporting force to the left. The pressure sensor detects the reaction to this supporting force, i.e., the pressure exerted by the brake disc on the mounting seat. Consequently, when the spring rate of the coil spring decreases, the elastic force decreases, and the pressure exerted by the brake disc on the mounting seat increases. This indicates whether spring rate attenuation has occurred, as determined by the pressure value detected by the pressure sensor.

[0093] 4. As the brake disc moves toward and against the brake pad under the elastic force of the elastic element, the distance sensor detects the distance between the left end of the clearance groove and the right end of the motor shaft. Consequently, as the thickness of the brake pad decreases, the distance between the left end of the clearance groove and the right end of the motor shaft decreases. This distance value, detected by the distance sensor, indicates whether the brake pad thickness is decreasing.

[0094] 5. By adjusting the dynamic control equation of the elastic coefficient of the magnetorheological spring, a joint control relationship is established between the adjustment value of the elastic coefficient of the magnetorheological spring and the detection value of the sensor that detects the elastic coefficient attenuation of the coil spring and the thickness change of the brake disc. This can quickly and accurately adjust the elastic coefficient of the magnetorheological spring, which is conducive to dynamically compensating the elastic coefficient of the elastic unit and ensuring that the elastic force of the elastic unit on the brake disc is always greater than the threshold during braking.

[0095] The foregoing description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be readily conceived by a person skilled in the art within the technical scope disclosed herein are intended to be encompassed within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

Claims

1. A brake motor with automatic braking torque compensation function, comprising a motor body and a brake mounted on one side of the motor body; The motor body includes a motor housing and a motor shaft, one end of the motor shaft extends out of the motor housing to connect to a load device, and the other end of the motor shaft extends out of the motor housing and is transmission-connected to a brake; A brake disc is provided in the brake, and the brake disc is mounted on the motor shaft by a key connection; The brake is further provided with an electromagnet fixedly and a brake disc slidably arranged therein, and the brake disc is located between the brake disc and the electromagnet, and the sliding direction of the brake disc is toward the brake disc; A guide rod is fixedly provided in the brake parallel to the axial direction of the motor shaft, and the guide rod passes through the brake disc and is slidably connected to the brake disc; An armature is fixedly provided on the brake disc, and an elastic element is also provided in the brake, and the elastic force of the elastic element drives the brake disc to press the brake disc; It is characterized in that The elastic unit includes a magnetorheological spring and a coil spring. The magnetorheological spring is fixedly installed in the brake. One end of the coil spring is fixedly installed on the magnetorheological spring, and the other end is fixedly installed on the brake disc. A pressure column is provided on the end of the brake disc facing the mounting seat; a pressure groove that is adapted to the pressure column is provided on the end of the mounting seat facing the brake disc, and a pressure sensor is installed in the pressure groove; a clearance groove is provided on the end of the brake disc facing the brake disc, and a distance sensor is installed in the clearance groove; The dynamic control equation for adjusting the elastic coefficient of the magnetorheological spring is: Where F is the magnetic attraction force on the brake disc when the brake motor is in working state and the electromagnet is energized to generate magnetic force to attract the brake disc; P is the pressure value detected by the pressure sensor when the brake motor is in working state and the electromagnet is energized to generate magnetic force to attract the brake disc; d1 is the length of the elastic unit compressed when the brake motor is in working state and the electromagnet is energized to generate magnetic force to attract the brake disc; k M0 is the initial elastic coefficient of the magnetorheological spring; k SC is the elastic coefficient of the coil spring after performance attenuation; d2 is the length of the elastic unit compressed when the brake disc is in the initial thickness state, the brake motor stops working, the power supply of the electromagnet is cut off, and the brake disc moves toward the brake disc and presses against the brake disc; d0 is the distance value detected by the distance sensor when the brake disc is in the initial thickness state, the brake motor stops working, the power supply of the electromagnet is cut off, and the brake disc moves toward the brake disc and presses against the brake disc; d is the distance value detected by the distance sensor when the brake disc becomes thinner, the brake motor stops working, the power supply of the electromagnet is cut off, and the brake disc moves toward the brake disc and presses against the brake disc; k M To dynamically adjust the elastic coefficient of the magnetorheological spring; K0 is the overall initial elastic coefficient of the elastic unit; in, Where K S0 is the initial elastic constant of the coil spring.

2. The brake motor with automatic braking torque compensation function according to claim 1, characterized in that: The magnetorheological spring includes a coil support, an excitation coil and an elastic body unit; The coil support is fixedly mounted on the base and is provided with an inner cylinder, a middle cylinder and an outer cylinder in sequence from the inside to the outside; The excitation coil is wound around the outside of the middle cylinder, the elastic body unit is arranged between the inner cylinder and the middle cylinder, and the top end of the middle cylinder is provided with an annular flange extending inward.

3. The brake motor with automatic braking torque compensation function according to claim 2, characterized in that: The elastic body unit includes several magnetorheological elastic bodies and soft iron sheets. A soft iron sheet is arranged between two adjacent magnetorheological elastic bodies. The magnetorheological elastic bodies and the soft iron sheet are both annular and sleeved on the outside of the inner cylinder.

4. The brake motor with automatic braking torque compensation function according to claim 2, characterized in that: In the initial state, when the brake motor stops working and the power supply of the electromagnet is cut off, the magnetorheological spring is not energized.

5. The brake motor with automatic braking torque compensation function according to claim 1, characterized in that: The brake comprises a brake housing, and the brake housing is provided with an avoidance hole for the other end of the motor shaft to extend into; The brake housing is fixedly connected to the motor housing, and a mounting cavity communicating with the avoidance hole is provided in the brake housing.

6. The brake motor with automatic braking torque compensation function according to claim 5, characterized in that: The brake disc includes a brake shoe for contacting the brake disc, and the brake shoe is detachably connected to the brake disc via bolts; The hardness of the brake pad is lower than that of the brake disc, and wear is caused by the brake pad when the two come into contact with each other for braking; The brake block is provided with a brake surface for contacting the brake disc, and the brake disc is provided with a brake surface for contacting the brake block. Both the brake surface and the brake surface are annular, and the motor shaft is located inside the inner ring of the brake surface, and the motor shaft does not contact the brake disc.

7. The brake motor with automatic braking torque compensation function according to claim 5, characterized in that: A mounting seat is fixedly installed in the mounting cavity, and the electromagnet is fixedly installed in the mounting seat by bolts; A base is also fixedly mounted on the outer periphery of the lower end of the mounting seat, and the end of the guide rod is fixedly mounted on the base; The elastic element is sleeved on the guide rod, one end of the guide rod is connected to the brake disc, and the other end of the guide rod is connected to the base.

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