Gear wear compensation method and related equipment

Abstract

The invention belongs to the technical field of automobile thermal management systems, and particularly relates to a gear wear compensation method and related equipment. The gear wear compensation method comprises the steps that when a motor is subjected to reversing, the number of rotation turns of the motor is controlled to be an error correction value, and the error correction value is obtained through the following steps that S1, when an output shaft of a gearbox is stopped at two swing stop points, the number of operation turns of the motor is recorded, and the actual number of operation turns of the motor is obtained; and S2, solving the difference between the actual number of operation turns of the motor and the theoretical number of operation turns of the motor to obtain an actual error value, summing the theoretical number of operation turns of the motor and the actual error value to obtain a compensated error correction value, and updating the error correction value to a preset position. Compared with two existing technologies, the method and the device have the advantages that traditional compensation logic is separated, existing in-loop compensation is directly changed into out-loop compensation, the control complexity of multistage gear transmission is reduced, the technology implementation is more convenient, and the control method and the device are more stable.

Description

Technical Field

[0001] The invention belongs to the technical field of automobile thermal management systems, and in particular relates to a gear wear compensation method and related equipment. Background Art

[0002] The water valve assembly in the automotive thermal management system is usually composed of a valve body, a valve core, and a control actuator. The mechanical part composed of the valve body and the valve core manages the refrigerant circulation path, and the control actuator is connected to the valve core through a spline to adjust the opening and closing angle of the valve core. Under the current automotive control requirements and the development of control chips, a precision control requirement of ±1° is proposed, which places very high demands on the entire water valve assembly.

[0003] The control accuracy of the entire water valve assembly depends on two points: the first is the assembly tolerance and manufacturing tolerance of the overall structure, such as the fitting tolerance of the valve body and valve core, the fitting tolerance of the valve core and control actuator, and the manufacturing tolerance of parts; the second is the control tolerance from the control actuator, such as the control execution accuracy of the control actuator, the compensation accuracy of the return difference, and the wear compensation accuracy of the gear.

[0004] The valve assembly will wear out after long-term use, and the wear error will bring new errors, which are corrected by controlling the actuator. The error caused by wear comes from the wear and deformation of the manufacturing gear material. Due to the irreversibility of wear, the wear will become larger and larger during the life cycle, and the error accuracy caused will also become larger and larger.

[0005] The existing technology in this field mainly has two compensation logics: cumulative compensation and matrix compensation. Cumulative compensation performs linear compensation based on the number of times the water valve component works; matrix compensation uses the inherent connections of materials, ambient temperature of the water valve component life cycle, load of the water valve life cycle, etc. to form a function matrix table of wear error and multiple characteristics. The above two compensation logics have one simple logic with large errors, and the other complex logic is difficult to implement. Summary of the invention

[0006] The present invention aims to provide a gear wear compensation method and related equipment to solve the technical problem that the compensation of wear error of a water valve assembly in an automobile thermal management system is large in error and has complex logic and is difficult to implement.

[0007] In order to solve the above technical problems, a first aspect of the present invention provides a gear wear compensation method, the gear wear compensation method comprising:

[0008] When the motor is commutating, the number of rotations of the motor is controlled to be the error correction value stored in the preset position, and the error correction value is obtained in the following manner:

[0009] S1, when the output shaft of the gear box stops at two swing stop points respectively, record the number of revolutions of the motor connected to the input shaft, and obtain the actual number of revolutions of the motor when the output shaft performs a cycloidal motion;

[0010] S2, subtracting the actual number of motor running circles from the theoretical number of motor running circles to obtain an actual error value, summing the theoretical number of motor running circles and the actual error value to obtain a compensated error correction value, and updating the error correction value to a preset position.

[0011] Optionally, in the gear wear compensation method as described above, the theoretical number of revolutions of the motor is calculated as follows:

[0012] Obtain the output shaft swing stroke in the control command, obtain the transmission reduction ratio of the gear box, and obtain the theoretical number of running circles of the motor according to the gear calculation formula n1=k×n2;

[0013] Among them, n1 is the theoretical number of running circles of the motor, k is the transmission reduction ratio, and n2 is the number of circles corresponding to the swing stroke of the output shaft.

[0014] Optionally, in the gear wear compensation method as described above, in step S2, when the actual error value is greater than the preset difference, the subsequent summation step is continued, and when the actual error value is not greater than the preset difference, it is considered that no error correction is required, and the subsequent steps are stopped.

[0015] Optionally, in the gear wear compensation method as described above, the transmission reduction ratio is preset in a register, and the register also stores the theoretical number of running revolutions of the motor.

[0016] Optionally, in the gear wear compensation method as described above, the error correction value is also stored in the register, and when a new error correction value is obtained in step S2, the error correction value stored in the register is updated.

[0017] Optionally, in the gear wear compensation method as described above, the gear wear compensation method further comprises:

[0018] S0, monitoring the number of revolutions of the motor, when the number of revolutions of the motor reaches a preset number, sending a request for error correction to a host computer, and after receiving a correction permission command from the host computer, proceeding to step S1 to step S2.

[0019] Optionally, in the gear wear compensation method as described above, the gear wear compensation method further comprises:

[0020] S0, obtaining the control command sent by the host computer, and when there is a stop command at the swing stop point in the control command, performing steps S1 to S2.

[0021] In order to solve the above technical problems, the second aspect of the present invention provides a gear wear compensation device, comprising:

[0022] A compensation correction module, used to control the number of rotations of the motor to be the error correction value stored in a preset position when the motor is commutating;

[0023] A data acquisition module is used to record the number of revolutions of the motor connected to the input shaft when the output shaft of the gear box stops at two swing stop points respectively, so as to obtain the actual number of revolutions of the motor when the output shaft performs a cycloidal motion;

[0024] The data calculation module is used to calculate the difference between the actual number of motor running circles and the theoretical number of motor running circles to obtain an actual error value, sum the theoretical number of motor running circles and the actual error value to obtain a compensated error correction value, and store the error correction value in a preset position.

[0025] Optionally, in the gear wear compensation device as described above, it further includes:

[0026] The first trigger module is used for monitoring the number of revolutions of the motor, and when the number of revolutions of the motor reaches a preset number, sending a request for error correction to a host computer, and receiving a correction permission command from the host computer.

[0027] Optionally, in the gear wear compensation device as described above, it further includes:

[0028] The second trigger module is used to obtain the control command sent by the host computer and determine whether there is a stop command at the swing stop point in the control command.

[0029] In order to solve the aforementioned technical problem, the third aspect of the present invention provides an electronic device, comprising a memory and a processor, wherein the memory stores computer-readable instructions, and when the computer-readable instructions are executed by the processor, the processor executes the steps of the gear wear compensation method provided by the first aspect of the present invention.

[0030] In order to solve the aforementioned technical problem, the fourth aspect of the present invention provides a storage medium storing computer-readable instructions. When the computer-readable instructions are executed by one or more processors, the one or more processors execute the steps of the gear wear compensation method provided by the first aspect of the present invention.

[0031] The positive and progressive effects of the present invention are:

[0032] 1. Compared with the two existing technologies, the present invention breaks away from the traditional compensation logic and directly changes from the existing in-loop compensation to out-loop compensation, thereby reducing the control complexity of the multi-stage gear transmission, making the technical implementation more convenient, and the control method and device more stable.

[0033] 2. Compared with the cumulative compensation logic, the present invention has the advantage of closed-loop feedback, which can ensure that the output shaft accuracy is within the control range, instead of using open-loop position compensation logic, which is limited by the working scene of the material, such as high temperature, low temperature, grease aging and other conditions. The logic of the present invention is not affected by the working scene of the material because it directly skips the multi-stage gear loop.

[0034] 3. Compared with matrix compensation logic, the present invention reduces the complexity of the control system. Matrix compensation logic uses parameters that affect material properties and material parameter variables for fitting, and establishes an array to form a mathematical model. This algorithm has many variables, and it is necessary to collect a large amount of experimental data to verify the rationality of the mathematical model. At the same time, when using this mathematical model, due to the large number of variables, the stability of the system is reduced. These parameters belong to gear loop parameters, and the control of the present invention does not need to participate in the closed-loop calculation of these parameters, so the algorithm is simplified while increasing the redundancy of the control system. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The disclosure of the present invention will become more apparent with reference to the accompanying drawings. It should be understood that these drawings are only for illustrative purposes and are not intended to limit the scope of protection of the present invention. In the drawings:

[0036] Figure 1 A schematic diagram of a process for obtaining an error correction value of the present invention. DETAILED DESCRIPTION

[0037] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0038] It should be noted that the following embodiments and features therein may be combined with each other if there is no conflict.

[0039] In the description of the present invention, it should be noted that directional words such as the terms "outside", "middle", "inside", "outside", etc., which indicate directions and positional relationships, are based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and cannot be understood as limiting the specific protection scope of the present invention.

[0040] In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features. Therefore, the definition of "first" and "second" features can explicitly or implicitly include one or more of the features. In the description of the present invention, "several" and "a number" mean two or more, unless otherwise clearly and specifically defined.

[0041] An embodiment of the present invention provides a gear wear compensation method, which includes: when the motor is commutating, controlling the number of rotations of the motor to be an error correction value stored in a preset position.

[0042] Each time the motor commutates, the control system introduces the error correction value for control. After the error compensation is introduced, the error is compensated each time the motor commutates, thereby ensuring that the error is eliminated, thereby ensuring the accuracy of the output shaft.

[0043] At the initial stage, there is usually no gear wear phenomenon, and the error correction value is the theoretical number of motor revolutions. Therefore, the theoretical number of motor revolutions can be stored in the initial preset position as the error correction value.

[0044] In the above compensation and correction method, for the life of the gear, as the life cycle progresses, the elastic deformation of the gear and the gear meshing clearance will become larger and larger, that is, the error gradually increases from the initial smaller error range. At this time, the actual error value after the increase can be obtained according to the algorithm of the following steps S1 to S2. By modifying this value and introducing it into the control system, the accuracy within the life cycle can be guaranteed.

[0045] Reference Figure 1 , the error correction value of the present invention is obtained in the following manner:

[0046] S1, data collection: when the output shaft of the gearbox stops at two swing stop points respectively, the number of revolutions of the motor connected to the input shaft is recorded to obtain the actual number of revolutions of the motor when the output shaft makes a cycloidal motion.

[0047] In the water valve assembly of the automotive thermal management system, a motor is usually used to drive a gearbox to adjust the opening and closing angle of the valve core. The gearbox usually includes a multi-stage reduction transmission assembly formed by several gears. The input shaft is driven by the motor, and the motor rotates continuously. The output shaft is a cycloid motion. During the cycloid motion, there is a stop point at each end (also called a swing stop point).

[0048] The present invention utilizes the phenomenon that the output shaft stops at two dead points during cycloidal motion, combined with the fact that the input shaft can monitor the running speed and the number of running revolutions through a control panel, records the current number of running revolutions of the motor when the output shaft stops at the first dead point, and records the current number of running revolutions of the motor when the output shaft stops at the second dead point, and obtains the actual number of running revolutions of the motor by calculating the difference between the data recorded at the two dead point positions.

[0049] In specific implementation, a position sensor or a trigger device such as a proximity switch can be provided at each of the two dead point positions where the output shafts can stop, so as to determine whether the output shafts have swung to the dead point position. The data collection of the current number of motor revolutions can be implemented by using a sensor used in the prior art to monitor the number of revolutions / rotation angles.

[0050] S2, data calculation: subtract the actual number of motor running circles from the theoretical number of motor running circles to obtain the actual error value, sum the theoretical number of motor running circles and the actual error value to obtain the compensated error correction value, and update the error correction value to the preset position.

[0051] The actual error value is caused by the elastic deformation of the gear and the gear meshing clearance. The error caused can be eliminated by introducing the error into the control system.

[0052] In some embodiments, the theoretical number of motor revolutions is calculated as follows:

[0053] Get the output shaft swing stroke in the control command, get the transmission reduction ratio of the gearbox, and get the theoretical number of motor running circles according to the gear calculation formula n1=k×n2. Among them, n1 is the theoretical number of motor running circles, k is the transmission reduction ratio, and n2 is the number of circles corresponding to the output shaft swing stroke.

[0054] In this embodiment, the control command is usually sent from the upper computer to the control component of the water valve component, and the control component controls the number of revolutions of the motor. Theoretically, after the motor rotates the theoretical number of revolutions, the output shaft just realizes a cycloidal motion from one dead point to another.

[0055] In some embodiments, in step S2, when the actual error value is greater than the preset difference, the subsequent summing step is continued; when the actual error value is not greater than the preset difference, it is considered that no error correction is required, and the subsequent steps are stopped.

[0056] In this embodiment, when the actual error value is very small, that is, not greater than the preset difference, the gear wear problem can be ignored and no subsequent compensation is performed. At this time, the motor still drives the output shaft to perform cycloid motion according to the last number of running circles.

[0057] For example, when the actual error value is not greater than one circle, such as a few degrees or even a few tenths of a degree, it is considered to be very small.

[0058] In some embodiments, the transmission reduction ratio is preset in a register, and the register also stores the theoretical number of revolutions of the motor.

[0059] When it is necessary to find the difference between the actual number of motor revolutions and the theoretical number of motor revolutions, the theoretical number of motor revolutions is obtained from the register.

[0060] The theoretical number of motor revolutions may be written into the register at the initialization, or updated into the register after the theoretical number of motor revolutions is obtained according to the gear calculation formula n1=k×n2.

[0061] In some embodiments, the register also stores an error correction value. When a new error correction value is obtained in step S2, the error correction value stored in the register is updated.

[0062] So that when the motor is commutating, the error correction value is obtained from the register as the number of rotations of the motor corresponding to the next cycloid motion.

[0063] In some embodiments, however, due to different control commands and mandatory requirements related to functional safety, the controller in the control assembly cannot act autonomously. Furthermore, due to the error value calculation, a movement that does not conform to the control command must be performed, that is, staying at two dead points to calculate the difference. Therefore, in this embodiment, steps S1 to S3 are not performed in every cycloid movement.

[0064] Steps S1 to S3 can be triggered by the following two control scenarios to perform gear wear compensation:

[0065] In one embodiment, the gear wear compensation method further includes:

[0066] S0, trigger compensation correction: monitor the number of motor revolutions. When the number of motor revolutions reaches a preset number, send a request for error correction to the host computer. After receiving the correction permission command from the host computer, proceed to step S1 to step S2.

[0067] In this embodiment, the preset number of turns may be a number of trigger turns. For example, when the motor runs 10,000 times, 20,000 times, ... N ten thousand times, etc., that is, when it reaches a certain integer ten thousand times, an error correction request is sent to the host computer.

[0068] This triggering method of the present embodiment can be called a method of setting a stroke calibration command. During the entire life cycle of the water valve assembly, at least thirty thousand stroke calibration commands can be sent to ensure the accuracy of the stroke.

[0069] In another embodiment, the gear wear compensation method further comprises:

[0070] S0, trigger compensation correction: obtain the control command issued by the host computer, and when there is a stop command at the swing stop point in the control command, perform steps S1 to S2.

[0071] In this embodiment, the time interval during which the output shaft stays at a certain swing dead point can be multiplied to calculate the difference in the number of motor revolutions corresponding to two swing dead points and the subsequent error correction value.

[0072] Since the above two control scenarios do not conflict with each other, the above two control scenarios can be selected one or both as triggering conditions for gear wear compensation.

[0073] Embodiment 1:

[0074] The gearbox in the water valve assembly is a five-stage reduction transmission with a transmission reduction ratio of 1:600; the input shaft is driven by a motor, and the motor rotates continuously; the output shaft is a cycloid motion with a stroke of 0-240°, and there is a dead point at each end.

[0075] According to the gear calculation formula n1=k×n2, since the output shaft is limited to cycloidal motion, the entire stroke is n2=240 / 360=2 / 3, and the reduction ratio k=600. Substituting it into the above formula, we get n1=400.

[0076] According to the above calculation, the motor rotates 400 times and the output shaft completes the entire 240° stroke. However, due to gear clearance and manufacturing tolerances, actual measurement results show that the motor input shaft needs to rotate 420 times for the output shaft to complete the 240° stroke.

[0077] The actual measurement results are obviously 20 turns different from the theoretical calculation results of the gears. There are two sources of this error. One is that the gears will produce elastic deformation after loading, which will increase the number of input turns when the input shaft is transmitted to the output shaft. The other is that the manufacturing tolerance of the gears causes a gap when the gears are meshing, resulting in an idle stroke. The combined influence of the two causes the reduction ratio to be different from the actual design.

[0078] Due to the five-stage transmission, the error caused by elastic deformation and gear meshing clearance will take effect on each stage of transmission. The error occurs four times, accumulating 20 turns of error.

[0079] However, since the output shaft moves in a cycloidal motion, the direction of rotation will change frequently, and two phenomena will occur at the time of reversal: 1. The elastic deformation caused by the gear first disappears on the meshing surface and then regenerates on the other meshing surface; 2. The gear meshing clearance first increases on the meshing surface and then forms on the other meshing surface.

[0080] It can be found that in a finite number of observations, the errors caused by each swing elastic deformation and gear meshing clearance are the same. However, after the introduction of the concept of gear life, on the one hand, the gears will continue to wear, causing the gear clearance to increase; on the other hand, the reduction in tooth width will cause the elastic deformation of the gears to increase. After the two are superimposed, the error caused will increase with the increase in the number of operations, and cumulative compensation is introduced. However, due to different temperature, lubrication, load and other conditions, the error and the number of operations are not linearly related, so matrix compensation is introduced. However, the above two algorithms are error compensation logic based on a finite number of output conditions. Due to the limitations of observation conditions and operating conditions, more input conditions cannot be introduced.

[0081] During the observation of the entire operation process, it can be found that the output shaft is constantly performing cycloidal motion, and there is a dead point at each end. This embodiment utilizes this phenomenon, and in combination with the input shaft, the operating speed and number of running circles can be monitored through the control panel. When the output shaft stops at the first dead point, the number of motor running circles at this moment is recorded, and when the output shaft stops at the second dead point, the number of motor running circles at this moment is recorded. By calculating the difference between the data recorded at the two positions, the actual number of motor running circles is obtained. By subtracting the actual number of running circles from the theoretically calculated number of theoretical running circles of the motor, the actual error value caused by the elastic deformation of the gear and the gear meshing clearance can be obtained. By introducing the error caused into the control system, the control system introduces the difference every time the motor is commutated to eliminate the error generated.

[0082] Specifically, the actual error value is known to be 20 turns, and the motor is controlled to rotate 420 turns after the error is introduced. The difference is introduced for control each time. After the error compensation is introduced, the error is compensated at each commutation to ensure that the error is eliminated, thereby ensuring the accuracy of the output shaft.

[0083] The embodiment of the present invention further provides a gear wear compensation device, the device comprising:

[0084] A compensation correction module, used to control the number of rotations of the motor to be the error correction value stored in a preset position when the motor is commutating;

[0085] A data acquisition module is used to record the number of revolutions of the motor connected to the input shaft when the output shaft of the gear box stops at two swing stop points, so as to obtain the actual number of revolutions of the motor when the output shaft performs a cycloidal motion;

[0086] The data calculation module is used to calculate the difference between the actual number of motor running circles and the theoretical number of motor running circles to obtain an actual error value, sum the theoretical number of motor running circles and the actual error value to obtain a compensated error correction value, and update the error correction value to a preset position.

[0087] In some embodiments, the apparatus further comprises:

[0088] The first trigger module is used to monitor the number of motor revolutions. When the number of motor revolutions reaches a preset number, a request for error correction is sent to a host computer, and a correction permission command is received from the host computer.

[0089] In some embodiments, the apparatus further comprises:

[0090] The second trigger module is used to obtain the control command sent by the host computer and determine whether there is a stop command at the swing stop point in the control command.

[0091] An embodiment of the present invention further provides an electronic device, comprising a memory and a processor, wherein the memory stores computer-readable instructions, and when the computer-readable instructions are executed by the processor, the processor executes the steps of the gear wear compensation method provided in the above-mentioned embodiments of the present invention.

[0092] An embodiment of the present invention further provides a storage medium storing computer-readable instructions. When the computer-readable instructions are executed by one or more processors, the one or more processors execute the steps of the gear wear compensation method of the above-mentioned embodiments of the present invention.

[0093] The present invention is described in detail above in conjunction with the embodiments of the accompanying drawings. A person skilled in the art can make various variations of the present invention according to the above description. Therefore, some details in the embodiments should not be construed as limiting the present invention, and the present invention shall be protected by the scope defined by the attached claims.

Claims

1. A gear wear compensation method, characterized in that: The gear wear compensation method includes controlling the number of rotations of the motor to be an error correction value stored in a preset position when the motor is commutating, and the error correction value is obtained in the following manner: S1, when the output shaft of the gear box stops at two swing stop points respectively, record the number of revolutions of the motor connected to the input shaft, and obtain the actual number of revolutions of the motor when the output shaft performs a cycloidal motion; S2, subtracting the actual number of motor running circles from the theoretical number of motor running circles to obtain an actual error value, summing the theoretical number of motor running circles and the actual error value to obtain a compensated error correction value, and updating the error correction value to a preset position.

2. The gear wear compensation method according to claim 1, characterized in that: The theoretical number of motor revolutions is calculated as follows: Obtain the output shaft swing stroke in the control command, obtain the transmission reduction ratio of the gear box, and obtain the theoretical number of running circles of the motor according to the gear calculation formula n1=k×n2; Among them, n1 is the theoretical number of running circles of the motor, k is the transmission reduction ratio, and n2 is the number of circles corresponding to the swing stroke of the output shaft.

3. The gear wear compensation method according to claim 1, characterized in that: In step S2, when the actual error value is greater than the preset difference, the subsequent summing step is continued; when the actual error value is not greater than the preset difference, it is considered that no error correction is required, and the subsequent steps are stopped.

4. The gear wear compensation method according to claim 1, characterized in that: The transmission reduction ratio is preset in a register, and the register also stores the theoretical number of motor running circles.

5. The gear wear compensation method according to claim 4, characterized in that: The register also stores the error correction value. When a new error correction value is obtained in step S2, the error correction value stored in the register is updated.

6. The gear wear compensation method according to any one of claims 1 to 5, characterized in that: The gear wear compensation method further comprises: S0, monitoring the number of revolutions of the motor, and when the number of revolutions of the motor reaches a preset number, sending a request for error correction to a host computer, and after receiving a correction permission command from the host computer, proceeding to step S1 to step S2; And / or, the gear wear compensation method further comprises: S0, obtaining the control command sent by the host computer, and when there is a stop command at the swing stop point in the control command, performing steps S1 to S2.

7. A gear wear compensation device, characterized in that: The gear wear compensation device comprises: A compensation correction module, used to control the number of rotations of the motor to be the error correction value stored in a preset position when the motor is commutating; A data acquisition module is used to record the number of revolutions of the motor connected to the input shaft when the output shaft of the gear box stops at two swing stop points respectively, so as to obtain the actual number of revolutions of the motor when the output shaft performs a cycloidal motion; The data calculation module is used to calculate the difference between the actual number of motor running circles and the theoretical number of motor running circles to obtain an actual error value, sum the theoretical number of motor running circles and the actual error value to obtain a compensated error correction value, and store the error correction value in a preset position.

8. The gear wear compensation device according to claim 7, characterized in that: The gear wear compensation device also includes: The first trigger module is used to monitor the number of revolutions of the motor, and when the number of revolutions of the motor reaches a preset number, send a request for error correction to the upper computer, and receive a correction permission command from the upper computer; And / or, the gear wear compensation device further comprises: The second trigger module is used to obtain the control command sent by the host computer and determine whether there is a stop command at the swing stop point in the control command.

9. An electronic device, characterized in that: It comprises a memory and a processor, wherein the memory stores computer-readable instructions, and when the computer-readable instructions are executed by the processor, the processor executes the gear wear compensation method according to any one of claims 1 to 6.

10. A storage medium storing computer-readable instructions, characterized in that: When the computer-readable instructions are executed by one or more processors, the one or more processors execute the gear wear compensation method according to any one of claims 1 to 6.

Images