Calibration method and device and vehicle

Abstract

The invention relates to the technical field of motor control, and particularly provides a calibration method and a calibration device for calibrating a driving zero position of a motor and a vehicle. The calibration method comprises the following steps: acquiring a signal variable about the position change of a motor in the process of driving a moving part; the motor is controlled to drive the moving part to return to a preset mechanical limiting position, and the numerical value of the signal variable at the mechanical limiting position is determined as a base point value; determining a zero point value about the signal variable in a preset direction of the motor-driven moving part by taking the base point value as a reference and the set migration amount as an interval; and calibrating the position of the motor as a driving zero position when the value of the signal variable is the zero value. According to the calibration method provided by the invention, a spacing distance is set between the driving zero position of the motor and the mechanical limiting position, and the motor does not reach the mechanical limiting position when returning each time, so that the condition that mechanical collision occurs when the motor drives the moving part to return to the driving zero position can be improved.

Description

Technical Field

[0001] The present invention relates to the field of motor control technology, and in particular to a calibration method for calibrating the driving zero point position of a motor. In addition, the present invention also relates to a calibration device and a vehicle. Background Art

[0002] In various motor-driven moving parts devices or systems, the motor drives the moving part from a drive zero position, moves it forward to a target position, and then drives it back to the drive zero position. Therefore, during motor control, it is necessary to clearly determine the drive zero position to which the motor drives the moving part before it returns. This allows for accurate determination and recording of the motor's position changes, thereby enabling better control of the moving part's motion.

[0003] Current methods for calibrating the motor's drive zero point typically calibrate the motor's drive zero position to the point where the motor drives the moving part back and reaches a mechanical limit. This mechanical limit position is then used as the drive zero position. This results in mechanical collisions each time the motor retracts to the drive zero position, significantly reducing the lifespan of the motor and transmission mechanism. When calibrating the motor's drive zero point, a closed-loop position control method is used. However, since the motor's position prior to zero point calibration is unclear, achieving the required accuracy when using position-controlled motors to return to zero is difficult. Summary of the Invention

[0004] In view of this, the present invention aims to propose a calibration method to improve the situation where a mechanical collision occurs when the motor drives a moving part to return to a driving zero position.

[0005] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0006] A calibration method for calibrating a drive zero position of a motor, the calibration method comprising:

[0007] Acquiring a signal variable regarding a position change of the motor in a process of driving a moving part;

[0008] controlling the motor to drive the moving part to retract to a preset mechanical limit position, and determining the value of the signal variable at the mechanical limit position as a base point value;

[0009] Based on the base point value and with the set migration amount as an interval, the zero point value of the signal variable is determined in the preset direction of the moving part driven by the motor; when the numerical value of the signal variable is the zero point value, the position of the motor is calibrated as the driving zero point position.

[0010] Furthermore, determining the value of the signal variable at the mechanical limit position as the base point value includes:

[0011] After determining that the moving part has retreated to the mechanical limit position, accumulating the number of retreats and recording the current value of the signal variable;

[0012] Determine whether the accumulated number of rollbacks has reached a preset number of repetitions;

[0013] When the accumulated number of retractions does not reach the number of repetitions, firstly controlling the motor to drive the moving part to leave the mechanical limit position, and then controlling the motor again to drive the moving part to retract to the mechanical limit position;

[0014] When the accumulated number of backoffs has reached the number of repetitions, the average value of the recorded current values is taken as the base point value.

[0015] Furthermore, controlling the motor to drive the moving part back to the mechanical limit position includes: controlling the motor to drive the moving part back, and obtaining a load signal of the motor; when the load signal exceeds a set load threshold and lasts for a preset time, determining that the moving part has retracted to the mechanical limit position.

[0016] Furthermore, the signal variable is at least one of variables related to the motor rotation angle, drive current and output torque.

[0017] Furthermore, the migration amount is 0.5% to 2.0% of the total change of the signal variable during the movement of the moving part driven by the motor.

[0018] Compared with the prior art, the present invention has the following advantages:

[0019] (1) The calibration method of the present invention can judge the motion changes, driving speed, etc. of the motor and the moving part in real time by obtaining the signal variable about the position change of the motor in the process of driving the moving part; when the motor drives the moving part to retreat to the mechanical limit position, the value of the signal variable will no longer change. The value at this time is the corresponding value of the signal variable when the moving part is at the mechanical limit position. This value is determined as the base point value, and a base point value for calibrating the driving zero point position of the motor is determined on the signal variable; then, using the signal variable as the control quantity, the motor drives the moving part to move forward, so that the signal variable reaches a zero point value that is a preset migration amount away from the base point value, as the value corresponding to the driving zero point position. At this moment, the position reached by the motor driving the moving part is used as the driving zero point position of the motor, thereby completing the calibration of the driving zero point position. In this way, each time the motor drives the moving part to retreat to the driving zero point position, there will be a spacing distance between it and the mechanical limit position, thereby improving the situation where the motor will cause mechanical collision when driving the moving part back to the driving zero point position.

[0020] (2) By repeatedly controlling the motor to drive the moving part back to the mechanical limit position, multiple corresponding zero point values are obtained and averaged to determine the final zero point value used; this can effectively increase the correspondence accuracy between the zero point value and the mechanical limit position, thereby improving the calibration accuracy of the motor's drive zero point position.

[0021] (3) In the process of judging whether the motor drives the moving part to retreat to the mechanical limit position and reach the position, when the motor speed is zero, the value of the signal variable will remain static. At this time, it can be preliminarily determined that the moving part has retreated to the position. At this moment, mechanical limit occurs between the moving part and its assembly structure, and the load signals such as the motor's drive current and torque will change significantly. By setting a reasonable threshold, when the load signal exceeds the set threshold, it can be more accurately judged that the mechanical limit has occurred and the moving part has indeed reached the mechanical limit position. The improvement of the accuracy of the mechanical limit position judgment can correspondingly improve the accuracy of the zero point value determination, thereby improving the calibration accuracy of the drive zero point position.

[0022] (4) The signal variable uses a variable related to the rotation angle of the motor, which makes it easy to detect the rotation of the motor in real time through the existing angle sensor to obtain reliable signal variables.

[0023] (5) Setting a reasonable numerical range for the migration amount can form a reasonable size interval between the mechanical limit position and the drive zero position; that is, it guarantees the driving space distance of the motor to the moving part, and also ensures that no mechanical collision occurs when the moving part returns to the drive zero position.

[0024] Another object of the present invention is to provide a calibration device, comprising a mechanical limit mechanism, a detection device and a control unit;

[0025] The control unit can load and execute a stored computer program to implement the calibration method described in the present invention; the mechanical limit mechanism is used to limit the mechanical limit position, and the control unit obtains the signal variable through the detection device.

[0026] Furthermore, the mechanical limiting mechanism includes a base provided at the power output end of the motor, and a limiting fitting portion provided on the moving part; the moving part is guided on the base along the preset direction, and as the moving part retreats, the limiting fitting portion abuts against the base to limit the mechanical limiting position.

[0027] Furthermore, relative to the side where the motor is located, the piston is located on the other side of the base; when the piston is driven back by the motor and abuts against the base, the mechanical limit position is defined.

[0028] Furthermore, the detection device includes an angle sensor arranged in the motor.

[0029] Furthermore, the base is provided with a pin through-hole for the motor pin of the motor to pass through and / or an angle sensor through-hole for the signal output terminal of the angle sensor to pass through.

[0030] (1) The calibration device of the present invention can obtain signal variables about the position change of the moving part in real time by using a detection device during the process of the motor driving the moving part, and then the control unit executes the above calibration method, which can well realize the driving action of the motor on the moving part and calibrate a driving zero point position with a spacing distance from the mechanical limit position, which can improve the situation of mechanical collision between the moving part and its assembly structure when the motor drives the moving part to return to the driving zero point position, and has the technical advantages of the above calibration method.

[0031] (2) Providing a base at the power output end of the motor not only facilitates the installation and arrangement of the motor and moving parts, but also provides guidance conditions for the movement of the moving parts. The limit fitting portion on the moving part abuts against the base, which can well define the mechanical limit position required for calibration.

[0032] (3) The detection device uses an angle sensor, which is not only convenient for installation on the motor, but also has the advantages of mature and reliable technology.

[0033] (4) When the base is set at the power output end of the motor, the base also forms the end plate of the motor. By opening pin holes, angle sensor holes, etc. on the base, the motor pins and signal output terminals inside the motor can be partially extended to the outside of the motor to facilitate the connection of related circuits outside the motor.

[0034] The present invention also provides a vehicle equipped with an electronic braking system, wherein the electronic braking system is provided with the calibration device of the present invention. The vehicle of the present invention has the technical advantages of the calibration device described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The accompanying drawings, which constitute part of the present invention, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention. Terms such as front and back, top and bottom, etc., used therein are intended only to indicate relative positional relationships and do not constitute undue limitations on the present invention. In the accompanying drawings:

[0036] Figure 1 Schematic diagram of the overall control flow of the calibration method according to an embodiment of the present invention;

[0037] Figure 2 Schematic diagram of the specific control flow of steps S2 and S3 in the calibration method according to an embodiment of the present invention;

[0038] Figure 3 This is a schematic diagram of the assembly structure of the main components of the calibration device according to an embodiment of the present invention;

[0039] Figure 4 This is a schematic structural diagram of a side of the base facing the motor according to an embodiment of the present invention;

[0040] Figure 5 This is a schematic diagram of the assembly structure of the motor and angle sensor according to an embodiment of the present invention;

[0041] Figure 6 Schematic diagram of the system structure of the electronic mechanical braking system of a vehicle according to an embodiment of the present invention.

[0042] Description of reference numerals:

[0043] 1. Piston; 2. Piston rod;

[0044] 3. Base; 31. Mounting hole; 32. Angle sensor mounting surface; 33. Piston rod through hole; 34. Angle sensor through hole; 35. Pin through hole;

[0045] 4. Ball screw;

[0046] 5. Angle sensor; 51. Signal output terminal; 52. Magnetic field sensor; 53. Motor follower;

[0047] 6. Motor; 61. Motor pins; 62. Motor assembly surface; 63. Motor bolt holes;

[0048] 7. Motor fixing bolts; 8. Control unit. DETAILED DESCRIPTION

[0049] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0050] In the description of the present invention, it should be stated that if terms indicating directions or positional relationships such as "up, down, left, right, front, back, inside, outside" appear, they are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed or operate in a specific direction. Therefore, they cannot be understood as limiting the present invention.

[0051] Furthermore, in the description of the present invention, unless otherwise expressly defined, the terms "mounted," "connected," "connect," and "connector" should be interpreted broadly. For example, a connection can be a fixed connection, a removable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, an indirect connection through an intermediary, or internal communication between two components. Those skilled in the art will understand the specific meanings of these terms in the present invention based on the specific circumstances.

[0052] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0053] Example 1

[0054] This embodiment relates to a calibration method for calibrating the driving zero position of the motor 6, which can improve the situation where the motor 6 may cause mechanical collision when driving the moving part to return to the driving zero position; an exemplary control flow of the method is as follows Figure 1 and Figure 2 shown.

[0055] In general, the calibration method includes:

[0056] S1, obtaining a signal variable regarding the position change of the motor 6 in the process of driving the moving part;

[0057] S2, control the motor 6 to drive the moving part back to the preset mechanical limit position;

[0058] S3, determining the value of the signal variable at the mechanical limit position as the base point value;

[0059] S4. Based on the base point value and the set migration amount as an interval, determine the zero point value of the signal variable in the preset direction of the moving part driven by the motor 6;

[0060] S5. When the value of the signal variable is a zero point value, the position of the motor 6 is calibrated as the driving zero point position of the motor 6.

[0061] It should be noted that, based on the above-described overall calibration strategy, the technical solution of the present invention can adopt a variety of different specific implementations or control forms. For example, the aforementioned signal variable can be a variable related to the rotation angle of motor 6 or a variable related to the linear displacement of the moving part. The corresponding detection device for obtaining the signal variable can be an angle sensor 5 or a displacement sensor. The moving part can be the piston 1 in the vehicle's electronic mechanical braking system or another moving part driven by motor 6 to perform reciprocating motion. The aforementioned preset direction can be the forward and reverse direction of rotation angle or the forward and backward direction of linear reciprocating motion. Taking the moving part as the piston 1 in the vehicle's electronic mechanical braking system as an example, the moving part's retraction direction is the direction away from the brake pad. The preset direction of the moving part driven by motor 6 is the direction in which the moving part moves away from the mechanical limit position, moves forward to approach, and ultimately pushes against the brake pad. For parts required for the implementation of the overall solution but not covered in the above-described overall configuration, reasonable and flexible design can be made by referring to established configuration methods in the art and actual implementation conditions. The specific implementation scheme described below in this embodiment is merely a preferred example of the many possible solutions that can be formed by the various combinations and variations described above. In actual implementation, those skilled in the art can flexibly adjust and improve based on actual conditions. Obviously, the various combinations of the above-mentioned specific forms and their variations can form many solutions, as well as the specific implementation scheme of this embodiment, all fall within the scope of protection of the present invention.

[0062] To confirm the zero point value, the motor 6 needs to drive the moving part back to the mechanical limit position. Of course, the confirmation of the zero point value can be completed by simply returning in sequence. However, preferably, in the above-mentioned step S3, the motor 6 is repeatedly controlled to drive the moving part back to the mechanical limit position, and the average value of the signal variable at the mechanical limit position obtained multiple times is taken as the base point value. By repeatedly controlling the motor 6 to drive the moving part back to the mechanical limit position, multiple corresponding zero point values are obtained, and an average calculation is performed to determine the zero point value to be used. This can effectively increase the accuracy of the correspondence between the zero point value and the mechanical limit position, thereby improving the calibration accuracy of the drive zero point position of the motor 6.

[0063] Regarding step S2 above, there are of course various methods for determining whether the moving part has reached the mechanical limit position. In this embodiment, controlling the motor 6 to drive the moving part back to the mechanical limit position includes: controlling the motor 6 to rotate in the direction of driving the moving part back, and obtaining a load signal from the motor 6; when the load signal exceeds a set threshold, determining that the moving part has returned to the mechanical limit position.

[0064] When determining whether motor 6 has driven the moving part back to the mechanical limit position and reached its position, when the motor speed reaches zero, the value of the signal variable will remain stationary, at which point it can be preliminarily determined that the moving part has returned to its position. At this point, mechanical limit occurs between the moving part and its assembly structure, and load signals such as the drive current and torque of motor 6 will change significantly. By setting a reasonable threshold, when the load signal exceeds the set threshold, it can be more accurately determined that mechanical limit has occurred and the moving part has indeed reached the mechanical limit position. Improving the accuracy of mechanical limit position determination can correspondingly improve the accuracy of zero point determination, thereby improving the calibration accuracy of the drive zero point position.

[0065] Combined with the settings of steps S2 and S3 above, refer to Figure 2 As shown, steps S2 and S3 specifically include the following control steps:

[0066] S21, controlling the motor 6 to drive the moving part to retreat, and obtaining the load signal of the motor 6;

[0067] S22, determining whether the load signal exceeds a set load threshold; if the load signal exceeds the set load threshold, executing the subsequent step S23, otherwise returning to step S21;

[0068] S23, timing the duration of the load signal exceeding the set load threshold, and determining whether the duration reaches a preset time; if the preset time is reached, executing the subsequent step S24, otherwise returning to step S22;

[0069] S24, determining that the moving part has returned to the mechanical limit position;

[0070] S31, after determining that the moving part has retreated to the mechanical limit position, accumulating the number of retreats and recording the current value of the signal variable;

[0071] S32, determining whether the number of backoffs has reached the set number of repetitions; if the number of backoffs has reached the set number of repetitions, executing the subsequent step S34, otherwise executing the subsequent step S33;

[0072] S33, first controlling the motor 6 to drive the moving part forward in a preset direction for a distance, leaving the mechanical limit position, so as to control the motor 6 to drive the moving part back again, and then controlling the motor 6 to drive the moving part back to the mechanical limit position;

[0073] S34. Take the average value of each recorded current value (i.e., the value of the signal variable when retreating to the mechanical limit position each time) as the base point value.

[0074] Among them, the above-mentioned repetition times can be set to two, three, four times, etc., preferably set between 2 and 4 times; the above-mentioned motor 6 drives the moving part to move forward a certain distance, and the distance can be reasonably set, as long as it is ensured that the moving part has completely left the mechanical limit position.

[0075] By refining the above-mentioned steps S2 and S3, the accuracy of the base point value of the signal variable corresponding to the mechanical limit position can be further improved. The load signal exceeding the set load threshold is used as the primary condition for determining whether the moving part has retracted to the mechanical limit position. At the same time, the duration of the load signal exceeding the set load threshold is timed, and it is determined whether the duration has reached the preset time. This eliminates abnormal momentary fluctuations in the load signal due to interference and other reasons, thereby improving the accuracy and reliability of the determination of the moving part's retraction to the mechanical limit position.

[0076] Furthermore, by repeatedly controlling the motor 6 to drive the moving part back to the mechanical limit position, obtaining multiple corresponding zero point values, and performing average calculations, the correspondence accuracy between the zero point value and the mechanical limit position can be further increased, thereby improving the calibration accuracy of the driving zero point position of the motor 6.

[0077] In addition, as mentioned above, the signal variable can be a variable related to the rotation angle of motor 6 or a variable related to the linear displacement of the moving part. At the same time, variables such as the drive current or output torque of motor 6 can also be selected as the above-mentioned signal variables. By judging and converting the signal changes of the drive current or the output torque, the position changes of motor 6 in the process of driving the moving part can also be reflected. Moreover, the above-mentioned signal variables can be flexibly selected from the rotation angle, drive current and output torque, and can be selected from one or more. When multiple signal variables are selected, multiple signals can be collected and calculated to improve the accuracy of detection through mutual verification.

[0078] In this embodiment, the signal variable is a variable related to the rotation angle of the motor 6. Using a variable related to the rotation angle of the motor 6 facilitates real-time detection of the rotation of the motor 6 by the existing angle sensor 5 to obtain a reliable signal variable.

[0079] Regarding the setting of the above-mentioned migration amount, it can be reasonably set within the entire range of the movement of the moving part driven by the motor 6. Preferably, the migration amount can be set to 0.5% to 2.0% of the total change in the signal variable during the entire process of the motor 6 driving the moving part; so that the moving part can completely break away from the hard contact with the assembly structure after moving forward by a migration amount from the mechanical limit position to the drive zero point position. Setting a reasonable numerical range for the migration amount can form a reasonably sized interval between the mechanical limit position and the drive zero point position; that is, it ensures the driving space distance of the motor 6 to the moving part, and also ensures that no mechanical collision occurs when the moving part returns to the drive zero point position. When the signal variable is a variable related to the rotation angle of the motor 6, if the motor 6 needs to rotate 10 times within the entire range of the travel, that is, 3 signal variables °, the above-mentioned migration amount can be set between 18° and 72°; such as 18°, 20°, 25°, 30°, 50°, 60°, etc.

[0080] In summary, the calibration method of this embodiment can determine the motion changes, drive speed, and other conditions of the motor 6 and the moving part in real time by obtaining the signal variable related to the position change of the motor 6 during the process of driving the moving part. When the motor 6 drives the moving part back to the mechanical limit position, the value of the signal variable will no longer change. The value at this time is the corresponding value of the signal variable when the moving part is at the mechanical limit position. This value is determined as the base point value, and a base point value for calibrating the drive zero position of the motor 6 is determined on the signal variable. Then, using the signal variable as the control variable, the motor 6 is controlled to drive the moving part forward, so that the signal variable reaches a zero point value that is separated from the base point value by a preset migration amount, which is used as the value corresponding to the drive zero position. At this time, the position reached by the motor 6 driving the moving part is used as the drive zero position of the motor 6, thereby completing the calibration of the drive zero position. In this way, each time the motor 6 drives the moving part back to the drive zero position, there will be a distance between it and the mechanical limit position, thereby improving the situation where the motor 6 will cause mechanical collision when driving the moving part back to the drive zero position.

[0081] Example 2

[0082] This embodiment relates to a calibration device and a vehicle. The calibration device is used to calibrate the driving zero point position of the motor 6. An exemplary assembly structure of its main components is as follows: Figures 3 to 6 shown.

[0083] In general, the calibration device includes a mechanical limit mechanism, a detection device, and a control unit 8. The control unit 8 is capable of loading and executing a stored computer program to implement the calibration method provided in Example 1 and calibrate the drive zero position of the motor 6. The mechanical limit mechanism is used to define the mechanical limit position, and the control unit 8 obtains the aforementioned signal variable through the detection device.

[0084] Similar to the calibration method of Example 1, the calibration device of this embodiment can be used to calibrate the zero point position of the piston 1 driven by the motor 6 in a vehicle's electronic mechanical brake system, or to calibrate the zero point of other reciprocating moving parts driven by the motor 6. This embodiment is described using the vehicle's electronic mechanical brake system as an example.

[0085] Taking the vehicle's electronic braking system as an example, unlike traditional brake vacuum boosters, the calibration device's power assist comes from the output torque of a brushless motor. Motor 6 converts rotation into axial linear drive through a transmission mechanism, actuating the brake cylinder's piston 1. During the drive process, motor 6 must start from its zero position and drive piston 1 forward to push against the brake pads. After braking, motor 6 must retract piston 1 to release the brake pads from the brake disc.

[0086] Combined with the above-mentioned braking driving situation, in this embodiment, if Figure 3 、 Figure 4 As shown, the mechanical limit mechanism includes a base 3 mounted on the power output end of the motor 6 and a limit-matching portion mounted on the moving member. The moving member is guided along a predetermined direction (here, the axial direction of the motor 6) on the base 3. As the moving member retracts, the limit-matching portion abuts against the base 3, defining the mechanical limit position.

[0087] In the electronic mechanical braking system, the above-mentioned moving parts mainly include a piston rod 2 arranged on the base 3 along the axial guide of the motor 6, and a piston 1 arranged at the end of the piston rod 2; wherein, the end surface of the piston 1 facing the base 3 constitutes the above-mentioned limiting fitting portion. Specifically, the motor 6 drives the piston rod 2 to guide the piston 1 forward through the screw transmission mechanism to perform the braking action. The base 3 is set at the power output end of the motor 6, which not only facilitates the installation and arrangement of the motor 6, piston 1, etc., but also provides guiding conditions for the guided movement of the piston 1. The screw transmission mechanism is used between the motor 6 and the piston 1 to realize transmission, which not only has stable transmission performance and compact structure, but also can well convert the rotational motion of the motor 6 into the guided linear motion of the piston 1.

[0088] Of course, there are many forms of assembly between the base 3 and the motor 6, such as snap-on connection, screw connection, etc.; in this embodiment, a plurality of mounting holes 31 are provided on the base 3, and correspondingly, a motor bolt hole 63 is provided on the motor assembly surface 62 of the motor 6. The fixed connection between the base 3 and the motor 6 can be completed by passing through the motor bolt hole 63 and screwing into the mounting hole 31.

[0089] The specific arrangement of piston 1 offers a variety of structural options. In this embodiment, piston 1 is located on the opposite side of base 3 from the motor 6. When piston 1 is driven back by motor 6 and abuts base 3, the aforementioned mechanical stop position is defined. Positioning motor 6 and piston 1 on opposite sides of base 3 provides reasonable space for the braking action of piston 1.

[0090] In specific implementation, the above-mentioned screw transmission mechanism can be configured as follows: the screw transmission mechanism includes a ball screw 4 fixedly connected to the power output shaft of the motor 6, and a piston rod 2 fixedly connected to the piston 1. The piston 1 is guided and arranged on the base 3 through the piston rod 2. The piston rod 2 passes through the piston rod through hole 33 located in the middle of the base 3 and is threadedly engaged with the ball screw 4. When the motor 6 drives the ball screw 4 to rotate, it will drive the piston rod 2 to move forward and backward on the base 3, thereby driving the piston 1 to perform forward braking or retraction. In this way, the retracting moving part will abut against the base 3 when it reaches the mechanical limit position, thus forming a reliable mechanical limit.

[0091] In addition, if Figure 5 As shown, the detection device of this embodiment includes an angle sensor 5 arranged in the motor 6. The detection device adopts the angle sensor 5, which is not only easy to install on the motor 6, but also has the advantage of mature and reliable technology.

[0092] During specific assembly and configuration, an annular angle sensor mounting surface 32 can be provided on the side of the base 3 facing the interior of the motor 6, and the magnetic field sensing element 52 of the angle sensor 5 can be mounted on the angle sensor mounting surface 32. The motor follower 53 of the angle sensor 5 can then be fixed to the rotor of the motor 6 and rotate with the motor 6. In this way, the angle sensor 5 uses the principle of eddy current to measure the changes in the magnetic field between the magnetic field sensing element 52 and the motor follower 53. The transmitted signal variable is output to the control unit 8 via the signal output terminal 51, thereby determining the rotation angle of the motor 6. When the motor 6 is powered on and rotates, driving the motor follower 53 to rotate, the magnetic field around the motor follower 53 changes with the change in the rotation angle of the motor 6. Because the magnetic field sensed by the magnetic field sensing element 52 changes, and this change is related to the rotation angle of the motor follower 53 and the motor 6, the angle sensor 5 will generate different signals based on the changes in the magnetic field. This signal is transmitted to the control unit 8 via the signal output terminal 51 for signal processing, thereby determining the rotation angle position of the motor 6 and thus achieving optimal control of the motor 6.

[0093] Based on the above settings, if Figure 4As shown, the base 3 may be provided with pin holes 35 for the motor pins 61 of the power supply 6 to pass through, or angle sensor holes 34 for the signal output terminals 51 of the angle sensor 5 to pass through. Of course, the pin holes 35 and angle sensor holes 34 described above may also be provided simultaneously. When the base 3 is positioned at the power output end of the motor 6, the base 3 also forms the end plate of the motor 6. By providing the pin holes 35 and angle sensor holes 34 on the base 3, the motor pins 61 and signal output terminals 51 located inside the motor 6 can be partially extended to the outside of the motor 6, thereby facilitating the connection of related circuits outside the motor 6.

[0094] Based on the above-mentioned overall configuration, the ball screw 4 can be fixedly connected to the power output shaft of the motor 6 by means of press-fitting, thereby closely cooperating with the motor 6. The piston rod 2 is connected to the ball screw 4 via a thread, realizing a screw transmission between the two. The signal output terminal 51 passes through the angle sensor through-hole 34 on the base 3 and is connected to the signal line from the control unit 8; the magnetic field sensor 52 is fitted onto the angle sensor mounting surface 32 of the base 3, and the motor follower 53 is fixedly connected to the rotor of the motor 6. After rotating a certain angle to align the corresponding components and through-holes, the three motor pins 61 of the motor 6 are respectively passed through the three pin through-holes 35 on the base 3, and the ball screw 4 and the piston rod 2 are passed through the piston rod through-hole 33 on the base 3, thus completing the assembly of the motor 6, the base 3, and the piston rod 2. Finally, the piston 1 is tightened and fixed to the end of the piston rod 2.

[0095] At this point, the piston 1, piston rod 2, base 3, ball screw 4, angle sensor 5 and motor 6 constitute the driving mechanism of the calibration device, completing the calibration device assembled as above. The radial and axial positioning of the angle sensor 5 are very precise, and the entire assembly structure has a high degree of integration and simple assembly operation.

[0096] Based on the above overall configuration, combined with Figure 6 As shown, the working principle of the calibration device of this embodiment is as follows:

[0097] After the entire drive mechanism is assembled, the rotation angle of the motor 6 is uncertain, which will cause the position of the piston 1 in the drive mechanism to be uncertain. Therefore, the state of the entire drive mechanism after assembly is unknown, so a calibration process for the drive zero point position of the motor 6 is required. The signal variable detected by the angle sensor 5 can reflect the position change of the motor 6 driving process, and then judge the state of the entire mechanism. Through the control of the control unit 8, the motor control method of current control (torque, speed) is used to control the motor 6 to rotate along the retreat direction of the drive mechanism. The ball screw 4 converts the rotational motion of the motor 6 into linear motion, thereby driving the piston rod 2 and the piston 1 to retreat until the piston 1 is tightly fitted and abutted with the base 3. Since the two structures are rigidly fitted, a mechanical limit effect is achieved, causing the piston rod 2 and the piston 1 to be unable to continue to be pulled by the rotational motion of the motor 6 and continue to move backward, thereby causing the motor 6 to be unable to continue to rotate. At this point, the load signals of motor 6, such as the drive current and torque, will increase significantly. When the drive current (torque) exceeds a certain load threshold, the vehicle's ECU (Electronic Control Unit) or the like, acting as a control unit 8, can determine that motor 6 has driven the moving part to the mechanical limit position by determining the change in the load signal of motor 6 and whether it exceeds the load threshold set by the flow rate. Simultaneously, angle sensor 5 records the position of motor 6 at this time. The value of the signal variable output by angle sensor 5 is the base point value; this base point value corresponds to the mechanical limit position. To ensure the accuracy of zero point calibration, motor 6 can be controlled to rotate in the forward direction of the drive mechanism, driving piston 1 forward a distance away from base 3, then retracting to a position closely aligned with base 3 (mechanical limit position), and repeating the base point value. Using the control method described above, this position is recorded as the mechanical limit position of the transmission mechanism. This cycle is repeated three or more times, and the base point values corresponding to the mechanical limit positions are calculated. The average of these multiple base point values is taken as the final base point value.

[0098] Afterwards, based on the position corresponding to the base point value, the motor 6 is controlled again to drive the piston 1 to move forward a distance determined by the migration amount (such as the motor 6 rotates 30°), so that the piston 1 and the base 3 are out of hard contact. At this moment, the value of the signal variable output by the angle sensor 5 is the zero point value. Correspondingly, the position of the motor 6 at this time can be calibrated as the driving zero point position of the motor 6.

[0099] It can be seen that the present invention proposes a new calibration device and a matching calibration method, which can not only solve the limitations of the existing calibration method of the angle sensor 5 of the motor 6 during the torque control, speed control and other processes of the motor 6, but also further improve the convenience of use, positioning accuracy, and structural reliability of the angle sensor 5 in the mechanical brake structure, and help reduce the manufacturing cost of the calibration device.

[0100] The calibration device of the present invention adopts a matching calibration method, which can accurately mark the driving zero point position of the motor 6 after the motor 6, the angle sensor 5 and the piston 1 are assembled. The method is simple, easy to operate, and the calibration process takes a short time and is highly efficient. In addition, by adopting the above-mentioned calibration method, the mechanical limit position and the driving zero point position of the motor 6 in the entire driving mechanism can be effectively distinguished, which can effectively avoid the situation where a mechanical collision occurs between the piston 1 and the base 3 each time the motor 6 drives the piston 1 to return to its original position; and after the driving zero point position of the driving mechanism is calibrated, the control accuracy of the angle sensor 5 on the driving position change of the motor 6 can be effectively improved, avoiding the situation where the motor 6 is positionally disordered and rotates randomly after completing the driving work of the braking action each time.

[0101] To sum up, the calibration device of the present invention can obtain signal variables about the position changes of the moving parts in real time by using the detection device during the process of the motor 6 driving the moving parts, and then the control unit 8 executes the above-mentioned calibration method, which can well realize the driving action of the motor 6 on the moving parts, and calibrate a driving zero point position with a spacing distance from the mechanical limit position, which can improve the situation of mechanical collision between the moving parts and their assembly structure when the motor 6 drives the moving parts to return to the driving zero point position, and has the technical advantages of the above-mentioned calibration method.

[0102] The foregoing description is merely a preferred embodiment of the present invention. The detailed configuration explanations, specific structural configuration examples, and assembly connection descriptions are provided for the purpose of providing sufficient disclosure to facilitate the implementation of the present invention by those skilled in the art, and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A calibration method for calibrating the drive zero position of a motor (6), characterized in that: The calibration method comprises: Acquiring signal variables related to position changes of the motor (6) in the process of driving a moving part; Controlling the motor (6) to drive the moving part to retreat to a preset mechanical limit position, and determining the value of the signal variable at the mechanical limit position as a base point value; Taking the base point value as a reference and the set migration amount as an interval, determining the zero point value of the signal variable in the preset direction in which the motor (6) drives the moving part; When the value of the signal variable is the zero point value, the position of the motor (6) is calibrated as the driving zero point position.

2. The calibration method according to claim 1, characterized in that: Determining the value of the signal variable at the mechanical limit position as the base point value includes: After determining that the moving part has retreated to the mechanical limit position, accumulating the number of retreats and recording the current value of the signal variable; Determine whether the accumulated number of rollbacks has reached a preset number of repetitions; When the accumulated number of retractions does not reach the number of repetitions, the motor (6) is first controlled to drive the moving part to leave the mechanical limit position, and the motor (6) is again controlled to drive the moving part to retract to the mechanical limit position; When the accumulated number of backoffs has reached the number of repetitions, the average value of the recorded current values is taken as the base point value.

3. The calibration method according to claim 1, characterized in that: The controlling of the motor (6) to drive the moving part to retreat to the mechanical limit position comprises: controlling the motor (6) to drive the moving part to retreat, and obtaining a load signal of the motor (6); When the load signal exceeds a set load threshold and lasts for a preset time, it is determined that the moving part retreats to the mechanical limit position.

4. The calibration method according to any one of claims 1 to 3, characterized in that: The signal variable is at least one of variables related to the rotation angle, drive current and output torque of the motor (6).

5. The calibration method according to any one of claims 1 to 3, characterized in that: The migration amount is 0.5% to 2.0% of the total change of the signal variable during the movement of the moving part driven by the motor (6).

6. A calibration device, characterized in that: It includes a mechanical limiting mechanism, a detection device and a control unit (8); The control unit (8) is capable of loading and executing a stored computer program to implement the calibration method according to any one of claims 1 to 5; The mechanical limiting mechanism is used to limit the mechanical limiting position, and the control unit (8) obtains the signal variable through the detection device.

7. The calibration device according to claim 6, characterized in that: The mechanical limit mechanism comprises a base (3) provided at the power output end of the motor (6), and a limit fitting portion provided on the moving part; the moving part is guided and provided on the base (3) along the preset direction, and as the moving part retreats, the limit fitting portion abuts against the base (3) to define the mechanical limit position.

8. The calibration device according to claim 7, characterized in that: The detection device comprises an angle sensor (5) arranged in the motor (6).

9. The calibration device according to claim 8, characterized in that: The base (3) is provided with a pin through-hole (35) for the motor pin (61) of the motor (6) to pass through and / or an angle sensor through-hole (34) for the signal output terminal (51) of the angle sensor (5) to pass through.

10. A vehicle equipped with an electronic braking system, characterized in that: The electronic braking system is provided with a calibration device according to any one of claims 6 to 9.

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