CN113280968A - Vehicle friction plate dragging torque test method, distribution diagram test method and device - Google Patents
Vehicle friction plate dragging torque test method, distribution diagram test method and device Download PDFInfo
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- CN113280968A CN113280968A CN202110503995.3A CN202110503995A CN113280968A CN 113280968 A CN113280968 A CN 113280968A CN 202110503995 A CN202110503995 A CN 202110503995A CN 113280968 A CN113280968 A CN 113280968A
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- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L5/00—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes
- G01L5/28—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes for testing brakes
Abstract
The invention provides a method for testing the dragging torque of a vehicle friction plate, a method for testing a distribution diagram and a device thereof, wherein the method for testing the dragging torque of the vehicle friction plate comprises the following steps: controlling the wheels to rotate at a preset rotating speed; acquiring a first resisting moment corresponding to the rotation of a wheel at a preset rotating speed when the friction plate of the vehicle is not removed, and acquiring a second resisting moment corresponding to the rotation of the wheel at the preset rotating speed when the friction plate is removed; and calculating the difference value of the first resisting moment and the second resisting moment to obtain the dragging moment of the friction plate. The scheme accurately reflects the resistance moment of the brake friction plate to the brake disc, is convenient for perfecting a brake system resistance evaluation system and is beneficial to development of low-resistance brake friction plates.
Description
Technical Field
The invention relates to the technical field of automobile braking performance testing, in particular to a method and a device for testing dragging torque of a vehicle friction plate and a distribution diagram.
Background
Energy conservation and environmental protection become the subjects of the automobile industry, and are the key of the healthy development of the automobile industry in the world. The braking system is an important safety part in an automobile running system, the performance of the braking system not only influences the safety, but also influences the fuel economy of an automobile by the friction torque between a brake friction plate and a brake disc, which is also called brake friction plate dragging torque, and the size of the braking friction plate dragging torque has certain influence on the running resistance of the automobile. Therefore, under the large background of energy conservation and environmental protection, the whole automobile factories and brake system suppliers pay attention to the development of low-resistance brake friction plates in addition to the automobile brake safety. The existing method for measuring the resisting moment of the braking system directly measures the resisting moment of wheels without measuring the dragging moment of a braking friction plate.
Disclosure of Invention
The invention mainly aims to provide a method for testing the dragging torque of a vehicle friction plate, a method and a device for testing a distribution diagram, and aims to solve the technical problem that the dragging torque of the brake friction plate is not measured by directly measuring the resisting torque of a wheel in the conventional method for measuring the resisting torque of a brake system.
In order to achieve the aim, the invention provides a method for testing dragging torque of a vehicle friction plate, which comprises the following steps:
controlling the wheels to rotate at a preset rotating speed;
acquiring a first resisting moment corresponding to the rotation of the wheel at the preset rotating speed when the friction plate of the vehicle is not removed, and acquiring a second resisting moment corresponding to the rotation of the wheel at the preset rotating speed when the friction plate is removed;
and calculating the difference value of the first resisting moment and the second resisting moment to obtain the dragging moment of the friction plate.
Preferably, the step of calculating the difference between the first resisting torque and the second resisting torque to obtain the friction plate dragging torque further comprises:
acquiring a plurality of end face runout quantities corresponding to the same position of each circle of the brake disc of the vehicle when the brake disc rotates;
obtaining an effective end face runout amount according to the end face runout amounts, wherein the effective end face runout amount is an average value of the end face runout amounts;
and verifying the dragging torque of the friction plate according to the effective end face jumping amount, and if the dragging torque of the friction plate is positively correlated with the effective end face jumping amount, judging that the dragging torque of the friction plate meets the requirement.
Preferably, the step of obtaining a first resisting torque corresponding to the rotation of the wheel at the preset rotation speed when the friction plate of the vehicle is not removed, and obtaining a second resisting torque corresponding to the rotation of the wheel at the preset rotation speed when the friction plate of the vehicle is removed comprises:
acquiring multiple groups of first testing resisting moments corresponding to the wheels rotating at multiple groups of preset rotating speeds in the state that the friction plates are not dismounted, and acquiring multiple groups of second testing resisting moments corresponding to the wheels rotating at multiple groups of preset rotating speeds in the state that the friction plates are dismounted;
according to the multiunit first test resisting moment acquires first resisting moment, first resisting moment is the multiunit the mean value of first test resisting moment to according to the multiunit second test resisting moment acquires second resisting moment, second resisting moment is the mean value of second test resisting moment.
Preferably, after the step of obtaining a plurality of sets of first test resisting torques corresponding to the wheel rotating at a plurality of preset rotating speeds in a state that the friction plate is not removed and obtaining a plurality of sets of second test resisting torques corresponding to the wheel rotating at a plurality of preset rotating speeds in a state that the friction plate is removed, and the step of calculating a mean value of the plurality of sets of first test resisting torques to obtain the first resisting torques and calculating a mean value of the plurality of sets of second test resisting torques to obtain the second resisting torques include:
calculating the difference value between the first test resisting moment under each group of preset rotating speeds and the second test resisting moment corresponding to the same group of preset rotating speeds, and obtaining the dragging moment of the test friction plate under each group of preset rotating speeds;
if the ratio of the standard deviation to the average value of the dragging torque of the plurality of groups of test friction plates is larger than a preset value, adding a group of newly-added preset rotating speeds on the basis of the plurality of groups of preset rotating speeds to form a test preset rotating speed group;
and acquiring the first test resisting moment of the wheel rotating at each rotating speed in the test preset rotating speed group when the friction plate is not dismounted, and acquiring the second test resisting moment of the wheel rotating at each rotating speed in the test preset rotating speed group when the friction plate is dismounted.
Preferably, the step of obtaining a first resisting torque corresponding to the rotation of the wheel at the preset rotation speed when the friction plate of the vehicle is not removed, and obtaining a second resisting torque corresponding to the rotation of the wheel at the preset rotation speed when the friction plate of the vehicle is removed comprises:
acquiring a first resisting moment difference value between the maximum value and the minimum value of the first resisting moment in a first time period when the vehicle rotates at the preset rotating speed, and acquiring the first resisting moment when the first resisting moment difference value is smaller than a preset first threshold value; and acquiring a second resisting moment difference value between the maximum value and the minimum value of the second resisting moment in the first time period when the vehicle rotates at the preset rotating speed, and acquiring the second resisting moment when the second resisting moment difference value is smaller than a preset second threshold value.
In addition, the invention also provides a method for testing the dragging torque distribution diagram of the vehicle friction plate, which comprises the following steps:
controlling the wheels to rotate at a preset rotating speed;
acquiring the rotation time T of each circle of the wheel;
determining the number L of data acquisition points of each circle of the wheel according to the rotation time T of each circle, and determining the rotation angle omega of each data acquisition point;
acquiring a first resisting moment corresponding to the rotation of the wheel at the preset rotating speed when the friction plate of the vehicle is not removed, and acquiring a second resisting moment corresponding to the rotation of the wheel at the preset rotating speed when the friction plate is removed;
determining a distribution diagram of the first resisting moment and the second resisting moment of each data acquisition point along the circumference according to the rotation angle omega of each data acquisition point and the first resisting moment and the second resisting moment of each data acquisition point;
wherein, the time T of each rotation is 60/N;
the number L of the data acquisition points is f.T;
each data acquisition point rotation angle omega is (360 · N · t)/60;
in the formula, N is the preset rotation speed, f is the data acquisition frequency, and t is the time set of each data acquisition point.
Preferably, after the step of determining the number L of data acquisition points per revolution of the wheel according to the rotation time T per revolution and determining the rotation angle ω of each data acquisition point, and the step of obtaining a first resisting torque corresponding to the wheel rotating at the preset rotation speed in a state that a friction plate of the vehicle is not removed, and obtaining a second resisting torque corresponding to the wheel rotating at the preset rotation speed in a state that the friction plate is removed, the method includes:
acquiring a first acquisition point resisting moment of the data acquisition point at the same rotation angle omega of each circle of the wheel in the state that the friction plate is not removed, and acquiring a second acquisition point resisting moment of the data acquisition point at the same rotation angle omega of each circle of the wheel in the state that the friction plate is removed;
and acquiring the first resisting moment according to the first acquisition point resisting moments for a plurality of circles, wherein the first resisting moment is the mean value of the first acquisition point resisting moments for a plurality of circles, acquiring the second resisting moment according to the second acquisition point resisting moments for a plurality of circles, and the second resisting moment is the mean value of the second acquisition point resisting moments for a plurality of circles.
In addition, the invention also provides a vehicle friction plate dragging torque testing device, which comprises:
a support;
the driving assembly is arranged on the bracket and used for driving wheels of a vehicle to rotate;
the sensor assembly comprises a first sensor and a second sensor, the first sensor is arranged on the driving assembly and used for acquiring the rotating speed and the resisting moment of the rotation of the wheel, and the second sensor is used for acquiring the end face jumping quantity of the brake disc of the vehicle; and the number of the first and second groups,
and the control device is electrically connected with the driving assembly, the first sensor and the second sensor.
In addition, the invention also provides a vehicle friction plate dragging torque test method control device, which comprises the following steps: a memory, a processor and a test program stored on the memory and executable on the processor, the test program comprising a vehicle friction plate drag torque test program configured to implement the vehicle friction plate drag torque test method of any one of claims 1 to 5, and/or a vehicle friction plate drag torque profile test program configured to implement the vehicle friction plate drag torque profile test method of any one of claims 6 to 7.
The invention further provides a storage medium, on which a vehicle friction plate dragging torque test program and/or a vehicle friction plate dragging torque distribution diagram test program are/is stored, wherein the vehicle friction plate dragging torque test program is executed by a processor to realize the vehicle friction plate dragging torque test method according to any one of claims 1 to 5, and the vehicle friction plate dragging torque distribution diagram test program is executed by the processor to realize the vehicle friction plate dragging torque distribution diagram test method according to any one of claims 6 to 7.
The invention provides a method for testing dragging torque of a vehicle friction plate, which comprises the following steps: controlling the wheels to rotate at a preset rotating speed; acquiring a first resisting moment corresponding to the rotation of the wheel at the preset rotating speed when the friction plate of the vehicle is not removed, and acquiring a second resisting moment corresponding to the rotation of the wheel at the preset rotating speed when the friction plate is removed; and calculating the difference value of the first resisting moment and the second resisting moment to obtain the dragging moment of the friction plate. According to the scheme, the first resisting moment when the vehicle is in a state that the friction plate is not dismounted and the second resisting moment when the vehicle is in a state that the friction plate is dismounted are obtained at the preset rotating speed. Therefore, the difference value of the first resisting moment and the second resisting moment, namely the dragging moment of the friction plate, accurately reflects the resisting moment of the brake friction plate to the brake disc, is convenient for perfecting a resistance evaluation system of a brake system, and is beneficial to development of low-resistance brake friction plates.
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In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.
FIG. 1 is a schematic structural diagram of a control device of a vehicle friction plate dragging torque testing method in a hardware operating environment according to an embodiment of the invention;
FIG. 2 is a schematic flow chart of a method for testing drag torque of a friction plate of a vehicle according to a first embodiment of the present invention;
FIG. 3 is a schematic flow chart of a method for testing drag torque of a friction plate of a vehicle according to a second embodiment of the present invention;
fig. 4 is a schematic flow chart of a method for testing a dragging torque distribution diagram of a friction plate of a vehicle according to a first embodiment of the invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
It should be noted that, if directional indication is involved in the embodiment of the present invention, the directional indication is only used for explaining the relative positional relationship, the motion situation, and the like between the components in a certain posture, and if the certain posture is changed, the directional indication is changed accordingly.
In addition, if there is a description of "first", "second", etc. in an embodiment of the present invention, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention.
Under the large background of energy conservation and environmental protection, all whole automobile factories and brake system suppliers pay attention to the automobile braking safety and the development of low-resistance brake friction plates. The existing method for measuring the resisting moment of the braking system directly measures the resisting moment of wheels without measuring the dragging moment of a braking friction plate.
In view of the above, the invention provides a method and a device for testing drag torque of a vehicle friction plate, and a method and a device for testing a distribution diagram, so as to solve the problem that the drag torque of a wheel is directly measured without measuring the drag torque of the brake friction plate in the conventional method for measuring the drag torque of a brake system. Fig. 1 to 4 are diagrams illustrating an embodiment of a method, a method and a device for testing a distribution diagram of a drag torque of a friction plate of a vehicle according to the present invention.
Referring to fig. 1, fig. 1 is a schematic structural diagram of a control device of a vehicle friction plate dragging torque test method in a hardware operating environment according to an embodiment of the present invention.
As shown in fig. 1, the control device for the vehicle friction plate dragging torque test method may include: a processor 1001, such as a Central Processing Unit (CPU), a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. Wherein a communication bus 1002 is used to enable connective communication between these components. The user interface 1003 may include a Display screen (Display), and the optional user interface 1003 may further include a standard wired interface and a wireless interface, and the wired interface for the user interface 1003 may be a USB interface in the present invention. The network interface 1004 may optionally include a standard wired interface, a WIreless interface (e.g., a WIreless-FIdelity (WI-FI) interface). The Memory 1005 may be a Random Access Memory (RAM) Memory or a Non-volatile Memory (NVM), such as a disk Memory. The memory 1005 may alternatively be a storage device separate from the processor 1001.
Those skilled in the art will appreciate that the configuration shown in figure 1 does not constitute a limitation of the vehicle friction plate drag torque test method control means and may include more or fewer components than shown, or some components in combination, or a different arrangement of components.
As shown in fig. 1, memory 1005, identified as a computer storage medium, may include an operating system, a network communication module, a user interface module, and a vehicle friction lining drag torque test program, and/or a vehicle friction lining drag torque profile test program.
In the control device for the vehicle friction plate dragging torque test method shown in fig. 1, the network interface 1004 is mainly used for connecting a background server and performing data communication with the background server; the user interface 1003 is mainly used for connecting user equipment; the control device of the vehicle friction plate dragging torque test method calls the vehicle friction plate dragging torque test program and/or the vehicle friction plate dragging torque distribution diagram test program stored in the memory 1005 through the processor 1001, and correspondingly executes the vehicle friction plate dragging torque test method and/or the vehicle friction plate dragging torque distribution diagram test method provided by the embodiment of the invention.
Based on the hardware structure, the first embodiment of the vehicle friction plate dragging torque testing method is provided.
Referring to fig. 2, a schematic flow chart of a method for testing a drag torque of a friction plate of a vehicle according to a first embodiment of the present invention is shown, where the method for testing a drag torque of a friction plate of a vehicle includes the following steps:
s10: controlling the wheels to rotate at a preset rotating speed;
s20: acquiring a first resisting moment corresponding to the rotation of the wheel at the preset rotating speed when the friction plate of the vehicle is not removed, and acquiring a second resisting moment corresponding to the rotation of the wheel at the preset rotating speed when the friction plate is removed;
s30: calculating the difference value of the first resisting moment and the second resisting moment to obtain the dragging moment of the friction plate
The pad drag torque is a resistance force generated by continuous or intermittent contact friction between the brake pad and the brake disc (drum) when the vehicle is not braking. According to the scheme, the first resisting moment when the vehicle is in a state that the friction plate is not dismounted and the second resisting moment when the vehicle is in a state that the friction plate is dismounted are obtained at the preset rotating speed. Therefore, the difference value of the first resisting moment and the second resisting moment, namely the dragging moment of the friction plate, accurately reflects the resisting moment of the brake friction plate to the brake disc, is convenient for perfecting a resistance evaluation system of a brake system, and is beneficial to development of low-resistance brake friction plates. It can be understood that the preset rotation speed is not limited herein, and may be a set of preset rotation speeds, and the corresponding braking drag force is calculated; or a plurality of groups of preset rotating speeds are calculated to obtain a plurality of groups of braking dragging torques, and then the average value of the plurality of groups of braking dragging torques is calculated.
Referring to fig. 3, a schematic flow chart of a method for testing a drag torque of a friction plate of a vehicle according to a second embodiment of the present invention is shown, where the second embodiment of the method for testing a drag torque of a friction plate of a vehicle is as follows:
after the step of calculating the difference between the first resisting torque and the second resisting torque to obtain the friction plate dragging torque, the method further comprises the following steps:
s31: acquiring a plurality of end face runout quantities corresponding to the same position of each circle of the brake disc of the vehicle when the brake disc rotates;
s32: obtaining an effective end face runout amount according to the end face runout amounts, wherein the effective end face runout amount is an average value of the end face runout amounts;
s33: and verifying the dragging torque of the friction plate according to the effective end face jumping amount, and if the dragging torque of the friction plate is positively correlated with the effective end face jumping amount, judging that the dragging torque of the friction plate meets the requirement.
It should be noted that, the larger the effective end face runout of the vehicle brake disc is, the larger the dragging torque of the friction plate is; the smaller the effective end face runout of the vehicle is, the smaller the dragging torque of the friction plate is, and if the dragging torque of the friction plate is negatively related to the effective end face runout, the measuring data of the dragging torque of the friction plate is unreasonable, so that the accuracy of the braking dragging torque is tested by measuring the end face runout of the vehicle. In addition, the end face runout quantity of the same position of the multi-circle brake disc is measured, the average value of the end face runout quantity of the multi-circle brake disc is obtained through calculation and is used as the final end face runout quantity, the standard of the end face runout quantity as an inspection index is improved, and therefore an end face runout quantity-friction disc dragging torque closed-loop multi-dimensional evaluation system is established. It can be understood that the preset rotating speed for measuring the end face runout amount is close to 0, so that the measurement accuracy is improved, in the embodiment, 1rpm is selected as the preset rotating speed, and meanwhile, the measurement time is not less than 600 s.
The third embodiment of the vehicle friction plate dragging torque testing method provided by the invention is as follows:
the step of obtaining a first resisting moment corresponding to the wheel rotating at the preset rotating speed when the friction plate of the vehicle is not removed, and obtaining a second resisting moment corresponding to the wheel rotating at the preset rotating speed when the friction plate is removed comprises:
acquiring multiple groups of first testing resisting moments corresponding to the wheels rotating at multiple groups of preset rotating speeds in the state that the friction plates are not dismounted, and acquiring multiple groups of second testing resisting moments corresponding to the wheels rotating at multiple groups of preset rotating speeds in the state that the friction plates are dismounted;
according to the multiple groups, the first test resisting moment is obtained, the first resisting moment is the multiple groups, the mean value of the first test resisting moment is obtained, the second test resisting moment is obtained according to the multiple groups, and the second resisting moment is the mean value of the second test resisting moment
Measuring a plurality of groups of preset rotating speeds, a first test resisting moment in a state that the friction plate is not dismounted, and a second test resisting moment in a state that the friction plate is dismounted, calculating the average value of the plurality of groups of first test resisting moments to obtain a first resisting moment, and calculating the average value of the plurality of groups of second resisting moments to obtain a second resisting moment; and then the friction plate dragging torque is obtained by calculating the difference value of the first resisting torque and the second resisting torque. By calculating the resistance moments of multiple groups of preset rotating speeds, the measurement contingency is avoided, and the measurement precision is improved. It should be noted that the selection of the plurality of sets of preset rotation speeds is not limited, and in the embodiment, the plurality of sets of preset rotation speeds include, but are not limited to, 1rpm, 5rpm, 10rpm, 20rpm, 50rpm, and 100 rpm.
The fourth embodiment of the vehicle friction plate dragging torque testing method provided by the invention is as follows:
the step of obtaining a plurality of groups of first test resisting moments corresponding to the wheels rotating at a plurality of groups of preset rotating speeds in the state that the friction plates are not removed and obtaining a plurality of groups of second test resisting moments corresponding to the wheels rotating at a plurality of groups of preset rotating speeds in the state that the friction plates are removed, the step of calculating the mean value of the plurality of groups of first test resisting moments to obtain the first resisting moments and the step of calculating the mean value of the plurality of groups of second test resisting moments to obtain the second resisting moments comprises the steps of:
calculating the difference value between the first test resisting moment under each group of preset rotating speeds and the second test resisting moment corresponding to the same group of preset rotating speeds, and obtaining the dragging moment of the test friction plate under each group of preset rotating speeds;
if the ratio of the standard deviation to the average value of the dragging torque of the plurality of groups of test friction plates is larger than a preset value, adding a group of newly-added preset rotating speeds on the basis of the plurality of groups of preset rotating speeds to form a test preset rotating speed group;
and acquiring the first test resisting moment of the wheel rotating at each rotating speed in the test preset rotating speed group when the friction plate is not dismounted, and acquiring the second test resisting moment of the wheel rotating at each rotating speed in the test preset rotating speed group when the friction plate is dismounted.
In this embodiment, the difference between the first test resisting moment and the second test resisting moment corresponding to each group of preset rotating speeds is calculated to obtain a plurality of groups of test friction plate dragging moments, and the measurement data deviation is determined by determining whether the ratio of the standard deviation to the average value of the plurality of groups of test friction plate dragging moments is greater than a preset value. If the ratio of the standard deviation to the average value of the dragging torque of the multiple groups of test friction plates is smaller than a preset value, determining that the deviation of the measured data is within a reasonable range; if the ratio of the standard deviation to the average value of the dragging torques of the multiple groups of test friction plates is larger than the preset value, the measured data deviation is determined to be overlarge, a group of preset rotating speed is required to be added to measure the first test resisting torque and the second test resisting torque, the corresponding dragging torque of the test friction plates is calculated, and whether the ratio of the standard deviation to the average value of the updated dragging torques of the multiple groups of test friction plates is smaller than the preset value or not is calculated. If so, judging that the data is reasonable; if not, repeating the steps until the ratio of the standard deviation to the average value of the dragging torque of the plurality of groups of test friction plates is smaller than the preset value, and calculating the difference between the final average value of the first test resisting torque and the final average value of the second test resisting torque to obtain the dragging torque of the friction plates.
It should be noted that, in this embodiment, if the ratio of the standard deviation of the dragging torque of the multiple groups of test friction plates to the average value is greater than 3%, a group of preset rotation speeds needs to be increased; and the ratio of the standard deviation to the average value of the dragging torque of the multiple groups of test friction plates is less than 3%, and the data deviation is determined to be in a reasonable range.
The fifth embodiment of the test method for the dragging torque of the friction plate of the vehicle provided by the invention comprises the following steps:
the step of obtaining a first resisting moment corresponding to the wheel rotating at the preset rotating speed when the friction plate of the vehicle is not removed, and obtaining a second resisting moment corresponding to the wheel rotating at the preset rotating speed when the friction plate is removed comprises:
acquiring a first resisting moment difference value between the maximum value and the minimum value of the first resisting moment in a first time period when the vehicle rotates at the preset rotating speed, and acquiring the first resisting moment when the first resisting moment difference value is smaller than a preset first threshold value; and acquiring a second resisting moment difference value between the maximum value and the minimum value of the second resisting moment in the first time period when the vehicle rotates at the preset rotating speed, and acquiring the second resisting moment when the second resisting moment difference value is smaller than a preset second threshold value.
It should be noted that the first threshold and the second threshold may be manually input, or may be data stored in a memory, which is not limited herein. In this embodiment, control the wheel respectively and rotate first time quantum under the friction disc is not demolishd and demolishs the state with preset rotational speed, avoid measuring time short and data unstable, lead to appearing accidental error, judge simultaneously whether the difference that first moment of resistance and second moment of resistance are is at corresponding threshold value scope to obtain the high measured data of the degree of accuracy, reach the effect that improves the accuracy of first moment of resistance and second moment of resistance. In the present embodiment, the first time period is 100 to 140 seconds, preferably 120 seconds.
The sixth embodiment of the vehicle friction plate dragging torque testing method provided by the invention is as follows:
the step of controlling the wheels to rotate at the preset rotating speed is preceded by controlling the vehicle to run at the preset speed for a preset time.
The effect of the heat engine is achieved by enabling the vehicle to run on the experimental road at the preset speed for the preset time, so that the vehicle can run normally, and the vehicle is in a better measuring state. The preset speed is 30-100 km/h, preferably 80km/h, and the preset time is not less than 30 min. In addition, the vehicle friction plate dragging torque testing device can be subjected to heat engine at the rotating speed of 90-110 rpm in an idle mode, the rotating speed is preferably 100rpm, and the heat engine time is not less than 1800 s.
In addition, the present invention further provides a method for testing a distribution diagram of a dragging torque of a friction plate of a vehicle, please refer to fig. 4, which is a first embodiment of the method for testing the distribution diagram of the dragging torque of the friction plate of the vehicle provided by the present invention, and the implementation includes the following steps:
s100: controlling the wheels to rotate at a preset rotating speed;
s200: acquiring the rotation time T of each circle of the wheel;
s300: determining the number L of data acquisition points of each circle of the wheel according to the rotation time T of each circle, and determining the rotation angle omega of each data acquisition point;
s400: acquiring a first resisting moment corresponding to the rotation of the wheel at the preset rotating speed when the friction plate of the vehicle is not removed, and acquiring a second resisting moment corresponding to the rotation of the wheel at the preset rotating speed when the friction plate is removed;
s500: determining a distribution diagram of the first resisting moment and the second resisting moment of each data acquisition point along the circumference according to the rotation angle omega of each data acquisition point and the first resisting moment and the second resisting moment of each data acquisition point;
wherein, the time T of each rotation is 60/N;
the number L of the data acquisition points is f.T;
each data acquisition point rotation angle omega is (360 · N · t)/60;
in the formula, N is the preset rotation speed, f is the data acquisition frequency, and t is the time set of each data acquisition point.
It should be noted that, in this embodiment, the rotation angle ω of the data acquisition point is between 0 to 360 degrees, corresponding to the circumference of the brake disc, the time set t of each data acquisition point, that is, the set of time points at which the sensor acquires the resisting moment of the acquisition point, is set according to the requirement and the measurement frequency of the sensor, and the data acquisition frequency f in this embodiment is 10 Hz. This embodiment draws first moment of resistance and the distribution diagram of second moment of resistance on the circumference, is convenient for audio-visually look over first moment of resistance and the distribution of second moment of resistance on the brake disc circumference, and the difference of the first moment of resistance and the second moment of resistance that also can calculate corresponding turned angle position in addition is in order to obtain the distribution condition of corresponding friction disc dragging moment on the brake disc circumference. Therefore, the distribution condition of the dragging torque of the friction plate on the brake disc at each preset rotating speed can be obtained, the dragging torque of the brake can be tested from a microscopic angle and a macroscopic angle, and a system is evaluated well. In the formula, the unit of T of each circle of rotation time is s, the unit of preset rotating speed N is r/min, the unit of data acquisition frequency f is Hz, and the unit of T of a time set of data acquisition points is s.
The second embodiment of the method for testing the dragging torque distribution diagram of the vehicle friction plate provided by the invention is as follows:
after the step of determining the number L of data acquisition points per turn of the wheel according to the per-turn rotation time T and determining the rotation angle ω of each data acquisition point, and the step of obtaining a first resisting moment corresponding to the wheel rotating at the preset rotation speed when the friction plate of the vehicle is not removed, and obtaining a second resisting moment corresponding to the wheel rotating at the preset rotation speed when the friction plate is removed, the method comprises the following steps:
acquiring a first acquisition point resisting moment of the data acquisition point at the same rotation angle omega of each circle of the wheel in the state that the friction plate is not removed, and acquiring a second acquisition point resisting moment of the data acquisition point at the same rotation angle omega of each circle of the wheel in the state that the friction plate is removed;
and acquiring the first resisting moment according to the first acquisition point resisting moments for a plurality of circles, wherein the first resisting moment is the mean value of the first acquisition point resisting moments for a plurality of circles, acquiring the second resisting moment according to the second acquisition point resisting moments for a plurality of circles, and the second resisting moment is the mean value of the second acquisition point resisting moments for a plurality of circles.
This embodiment is through acquireing under being in the friction disc state of not demolising, the first acquisition point moment of resistance of every circle the same turned angle omega department to under acquireing the friction disc state of demolising, the second acquisition point moment of resistance of every circle the same turned angle omega department, the mean value that calculates many circles first acquisition point moment of resistance obtains first moment of resistance, the mean value that calculates many circles second acquisition point moment of resistance obtains the second moment of resistance, with the measuring accuracy who improves the moment of resistance of each turned angle omega department.
In addition, the invention also provides a vehicle friction plate dragging torque testing device which comprises a support, a driving assembly, a sensor assembly and a control device, wherein the driving assembly is arranged on the support and used for driving wheels of a vehicle to rotate; the sensor assembly comprises a first sensor and a second sensor, the first sensor is arranged on the driving assembly and used for acquiring the rotating speed and the resisting moment of the rotation of the wheel, and the second sensor is used for acquiring the end face runout of a brake disc of the vehicle; the control device is electrically connected with the driving assembly, the first sensor and the second sensor. It should be noted that the arrangement form of the second sensor is not limited, and the second sensor may be a magnetic induction sensor or a contact sensor, which is not limited herein. In this embodiment, the second sensor is a contact sensor, and the second sensor is in contact with the brake disc to measure the end face runout amount, can freely install in narrow and small position, is convenient for remove the installation. In addition, compare in traditional manually operation test equipment, the vehicle friction disc dragging torque testing arrangement of this scheme obtains the moment of resistance through the sensor and measures more accurately.
In addition, the invention also provides a vehicle friction plate dragging torque test method control device, which comprises the following steps: the test program comprises a vehicle friction plate dragging torque test program and/or a vehicle friction plate dragging torque distribution diagram test program, wherein the vehicle friction plate dragging torque test program is configured to realize the vehicle friction plate dragging torque test method, and the vehicle friction plate dragging torque distribution diagram test program is configured to realize the vehicle friction plate dragging torque distribution diagram test method.
In addition, the invention also provides a storage medium, wherein a vehicle friction plate dragging torque test program and/or a vehicle friction plate dragging torque distribution diagram test program are/is stored on the storage medium, the vehicle friction plate dragging torque test program is executed by the processor to realize the vehicle friction plate dragging torque test method, and the vehicle friction plate dragging torque distribution diagram test program is executed by the processor to realize the vehicle friction plate dragging torque distribution diagram test method.
The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by using the contents of the present specification and the accompanying drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.
Claims (10)
1. A method for testing dragging torque of a vehicle friction plate is characterized by comprising the following steps:
controlling the wheels to rotate at a preset rotating speed;
acquiring a first resisting moment corresponding to the rotation of the wheel at the preset rotating speed when the friction plate of the vehicle is not removed, and acquiring a second resisting moment corresponding to the rotation of the wheel at the preset rotating speed when the friction plate is removed;
and calculating the difference value of the first resisting moment and the second resisting moment to obtain the dragging moment of the friction plate.
2. The method for testing drag torque on a friction plate of a vehicle of claim 1 wherein said step of calculating the difference between said first resistive torque and said second resistive torque to obtain said drag torque on a friction plate further comprises:
acquiring a plurality of end face runout quantities corresponding to the same position of each circle of the brake disc of the vehicle when the brake disc rotates;
obtaining an effective end face runout amount according to the end face runout amounts, wherein the effective end face runout amount is an average value of the end face runout amounts;
and verifying the dragging torque of the friction plate according to the effective end face jumping amount, and if the dragging torque of the friction plate is positively correlated with the effective end face jumping amount, judging that the dragging torque of the friction plate meets the requirement.
3. The method for testing dragging torque of a friction plate of a vehicle according to claim 1, wherein the step of obtaining a first resisting torque corresponding to the wheel rotating at the preset rotating speed in a state that the friction plate of the vehicle is not removed, and obtaining a second resisting torque corresponding to the wheel rotating at the preset rotating speed in a state that the friction plate is removed comprises the steps of:
acquiring multiple groups of first testing resisting moments corresponding to the wheels rotating at multiple groups of preset rotating speeds in the state that the friction plates are not dismounted, and acquiring multiple groups of second testing resisting moments corresponding to the wheels rotating at multiple groups of preset rotating speeds in the state that the friction plates are dismounted;
according to the multiunit first test resisting moment acquires first resisting moment, first resisting moment is the multiunit the mean value of first test resisting moment to according to the multiunit second test resisting moment acquires second resisting moment, second resisting moment is the mean value of second test resisting moment.
4. The method for testing drag torque of a vehicle friction plate according to claim 3, wherein after the step of obtaining a plurality of sets of first test resisting torques corresponding to the rotation of the wheel at a plurality of sets of the preset rotation speeds in the friction plate unmounted state and obtaining a plurality of sets of second test resisting torques corresponding to the rotation of the wheel at a plurality of sets of the preset rotation speeds in the friction plate unmounted state, the step of calculating an average value of the plurality of sets of the first test resisting torques to obtain the first resisting torques and calculating an average value of the plurality of sets of the second test resisting torques to obtain the second resisting torques comprise:
calculating the difference value between the first test resisting moment under each group of preset rotating speeds and the second test resisting moment corresponding to the same group of preset rotating speeds, and obtaining the dragging moment of the test friction plate under each group of preset rotating speeds;
if the ratio of the standard deviation to the average value of the dragging torque of the plurality of groups of test friction plates is larger than a preset value, adding a group of newly-added preset rotating speeds on the basis of the plurality of groups of preset rotating speeds to form a test preset rotating speed group;
and acquiring the first test resisting moment of the wheel rotating at each rotating speed in the test preset rotating speed group when the friction plate is not dismounted, and acquiring the second test resisting moment of the wheel rotating at each rotating speed in the test preset rotating speed group when the friction plate is dismounted.
5. The method for testing dragging torque of a friction plate of a vehicle according to claim 1, wherein the step of obtaining a first resisting torque corresponding to the wheel rotating at the preset rotating speed in a state that the friction plate of the vehicle is not removed, and obtaining a second resisting torque corresponding to the wheel rotating at the preset rotating speed in a state that the friction plate is removed comprises the steps of:
acquiring a first resisting moment difference value between the maximum value and the minimum value of the first resisting moment in a first time period when the vehicle rotates at the preset rotating speed, and acquiring the first resisting moment when the first resisting moment difference value is smaller than a preset first threshold value; and acquiring a second resisting moment difference value between the maximum value and the minimum value of the second resisting moment in the first time period when the vehicle rotates at the preset rotating speed, and acquiring the second resisting moment when the second resisting moment difference value is smaller than a preset second threshold value.
6. A method for testing a dragging torque distribution diagram of a vehicle friction plate is characterized by comprising the following steps:
controlling the wheels to rotate at a preset rotating speed;
acquiring the rotation time T of each circle of the wheel;
determining the number L of data acquisition points of each circle of the wheel according to the rotation time T of each circle, and determining the rotation angle omega of each data acquisition point;
acquiring a first resisting moment corresponding to the rotation of the wheel at the preset rotating speed when the friction plate of the vehicle is not removed, and acquiring a second resisting moment corresponding to the rotation of the wheel at the preset rotating speed when the friction plate is removed;
determining a distribution diagram of the first resisting moment and the second resisting moment of each data acquisition point along the circumference according to the rotation angle omega of each data acquisition point and the first resisting moment and the second resisting moment of each data acquisition point;
wherein, the time T of each rotation is 60/N;
the number L of the data acquisition points is f.T;
each data acquisition point rotation angle omega is (360 · N · t)/60;
in the formula, N is the preset rotation speed, f is the data acquisition frequency, and t is the time set of each data acquisition point.
7. The method for testing the dragging torque distribution diagram of the vehicle friction plate according to claim 6, wherein after the steps of determining the number L of data acquisition points per circle of the wheel according to the rotation time T per circle and determining the rotation angle ω of each data acquisition point, and before the steps of obtaining a first resisting torque corresponding to the wheel rotating at the preset rotation speed in the state that the friction plate of the vehicle is not removed and obtaining a second resisting torque corresponding to the wheel rotating at the preset rotation speed in the state that the friction plate is removed, the method comprises the following steps:
acquiring a first acquisition point resisting moment of the data acquisition point at the same rotation angle omega of each circle of the wheel in the state that the friction plate is not removed, and acquiring a second acquisition point resisting moment of the data acquisition point at the same rotation angle omega of each circle of the wheel in the state that the friction plate is removed;
and acquiring the first resisting moment according to the first acquisition point resisting moments for a plurality of circles, wherein the first resisting moment is the mean value of the first acquisition point resisting moments for a plurality of circles, acquiring the second resisting moment according to the second acquisition point resisting moments for a plurality of circles, and the second resisting moment is the mean value of the second acquisition point resisting moments for a plurality of circles.
8. The utility model provides a vehicle friction disc dragging torque testing arrangement which characterized in that includes:
a support;
the driving assembly is arranged on the bracket and used for driving wheels of a vehicle to rotate;
the sensor assembly comprises a first sensor and a second sensor, the first sensor is arranged on the driving assembly and used for acquiring the rotating speed and the resisting moment of the rotation of the wheel, and the second sensor is used for acquiring the end face jumping quantity of the brake disc of the vehicle; and the number of the first and second groups,
and the control device is electrically connected with the driving assembly, the first sensor and the second sensor.
9. A vehicle friction plate dragging torque test method control device is characterized by comprising the following steps: a memory, a processor and a test program stored on the memory and executable on the processor, the test program comprising a vehicle friction plate drag torque test program configured to implement the vehicle friction plate drag torque test method of any one of claims 1 to 5, and/or a vehicle friction plate drag torque profile test program configured to implement the vehicle friction plate drag torque profile test method of any one of claims 6 to 7.
10. A storage medium, wherein a vehicle friction plate dragging torque test program and/or a vehicle friction plate dragging torque distribution diagram test program are/is stored on the storage medium, the vehicle friction plate dragging torque test program is executed by a processor to realize the vehicle friction plate dragging torque test method according to any one of claims 1 to 5, and the vehicle friction plate dragging torque distribution diagram test program is executed by the processor to realize the vehicle friction plate dragging torque distribution diagram test method according to any one of claims 6 to 7.
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