Method for indirectly monitoring abrasion condition of brake lining

Abstract

The invention discloses a method for indirectly monitoring the abrasion condition of a brake lining. The method comprises the following steps that S1, a standard change curve is drawn; replacing brake linings with different abrasion losses, and drawing a standard change curve of the deceleration and the output oil pressure of the whole vehicle according to the brake linings with different abrasion losses; s2, comparing with a standard change curve; in the actual driving process, according to the change curve of the whole vehicle deceleration and the output oil pressure, the change curve is compared with the standard change curve, and the abrasion loss of the brake lining is determined; s3, outputting the abrasion loss; the abrasion loss of the brake lining is displayed on an instrument panel for a driver to check in real time; compared with the prior art, the method has the beneficial effects that software upgrading is carried out only through the pre-set model in the early stage, existing vehicle hardware does not need to be modified, then in the vehicle running process, the monitored data are compared with the pre-set model, the abrasion loss of the brake lining is periodically updated after monitoring is carried out for a certain cycle, and the service life of the brake lining is prolonged. Therefore, the abrasion loss of the lining can be monitored in real time.

Description

Technical Field

[0001] The invention relates to the technical field of vehicle driving, and in particular to a method for indirectly monitoring the wear of a brake lining. Background Art

[0002] Brake linings, also known as brake pads, are installed on both sides of the brake disc (which is integrated with the wheel. When the vehicle is driving normally, the brake disc rotates synchronously with the wheel). When the vehicle slows down, the brake linings hold the brake disc from both sides to achieve braking deceleration. During the use of the vehicle, the brake linings will gradually wear out. In order to ensure the safety of the driving process, the wear of the brake linings needs to be monitored so that they can be replaced in time to eliminate driving hazards.

[0003] There are two main methods for monitoring the wear of brake linings in the market: one is to embed sensors in the brake linings, and when the brake linings are worn to the alarm level, the circuit is turned on and the driver is reminded to check or replace them through the instrument display; the other is to directly measure the change in the thickness of the brake linings through sensors. Of the above two solutions, the first one cannot determine the wear of the brake linings in real time, and the user experience is poor; the second one is more expensive and cannot be widely promoted.

[0004] The patent with the publication number of "CN114537362A" discloses "a monitoring and alarm device for brake lining wear of trailer brake pads", which includes a monitoring and alarm mechanism matched with the brake pad assembly, the monitoring and alarm mechanism includes a translation mechanism, a lifting mechanism, a lifting block and a shell, a translation block capable of horizontal movement is provided on the translation mechanism, a lifting mechanism is provided on the translation block, a first attraction block capable of lifting and lowering is provided on the lifting mechanism, a second attraction block capable of engaging with the first attraction block is provided on the lifting block, a touch block is elastically connected to the lifting block, a contact is provided on the touch block, an alarm switch is provided on the inner side of the shell at the corresponding contact position, an infrared sensor is provided on the translation block, and an infrared avoidance hole is provided on the lifting block. However, it can only alarm when the lining is worn to the limit position, and cannot monitor the wear of the lining in real time.

[0005] The patent with the publication number of "CN106402213A" discloses "device for monitoring the wear of brake friction linings of brakes", which has a first type of brake friction lining wear monitoring device (total wear monitoring device) and a second type of brake friction lining wear monitoring device (end wear monitoring device), and the first type of monitoring device and the second type of monitoring device are connected by means of a connecting element (13, 33). In addition, a device for expanding the function of a device (1, 20) for monitoring the wear of brake friction linings of brakes is also proposed, wherein the device has a connecting element (13, 33), and the connecting element is designed to establish a connection between the device for expanding the function and the device (1, 20) to be expanded. However, the monitoring device used therein has a high cost.

[0006] To this end, our company has proposed a method to indirectly monitor the wear of brake linings. Summary of the invention

[0007] The purpose of the present invention is to provide a method for indirectly monitoring the wear of brake linings, based on the existing technical status and components, through the pre-set model, the software is upgraded without increasing the hardware cost.

[0008] To achieve the above object, the present invention adopts the following technical solutions: A method for indirectly monitoring brake lining wear comprises the following steps: S1. Draw a standard change curve; replace brake linings with different wear amounts, and draw a standard change curve of vehicle deceleration and output oil pressure according to the brake linings with different wear amounts; S2. Comparison with the standard change curve: During actual driving, the change curve of vehicle deceleration and output oil pressure is compared with the standard change curve to determine the wear amount of the brake lining; S3, wear output; the wear of the brake lining is displayed on the instrument panel for the driver to view in real time.

[0009] Preferably, in S1, brake linings with wear amounts of 0%, 25%, 50%, 75% and 100% are selected respectively.

[0010] Preferably, the method further comprises step S4, a wear alarm; according to a preset limit wear amount of the lining, an alarm signal is issued when the limit wear amount of the lining is reached.

[0011] Preferably, the preset limit wear amount of the lining is 75%.

[0012] The beneficial effects of the present invention are: The software can be upgraded only through the pre-set model in the early stage without modifying the existing vehicle hardware. Later, during the driving process of the vehicle, the monitoring data is compared with the pre-set model. The wear of the brake lining is periodically updated after a certain monitoring cycle. The wear of the lining can be monitored in real time and a real-time reminder can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 The braking principle diagram of the vehicle; Figure 2 Schematic diagram of brake with lining wear of 0%; Figure 3 Schematic diagram of brake with lining wear of 50%; Figure 4 Schematic diagram of the brake with lining wear of 100%; Figure 5 It is the standard variation curve of vehicle deceleration and output oil pressure.

[0014] The drawings are only used for illustrative purposes and should not be construed as limitations on this patent. In order to better illustrate this embodiment, some parts of the drawings may be omitted, enlarged, or reduced, and do not represent the size of the actual product. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted. DETAILED DESCRIPTION

[0015] The present invention is further described below in conjunction with the accompanying drawings.

[0016] Embodiment 1 like Figure 1 As shown in the figure, it is a schematic diagram of the braking principle of the vehicle. When the vehicle decelerates, the driver steps on the pedal above the master cylinder 2 to control the brake 1 to tighten. At this time, the anti-skid actuator 3 monitors the oil pressure and the deceleration of the whole vehicle and outputs it in the form of data. The anti-skid actuator (or ABS / ESC) is an existing mature technology and will not be described in detail in this embodiment. Its built-in pressure sensor can monitor the pipeline oil pressure in real time.

[0017] like Figure 2 — Figure 4The figure shows the structure of the brake 1 in this embodiment when the lining has different wear amounts. The brake disc 11 is arranged on the wheel. The lining includes a first lining 12 and a second lining 13 located on both sides of the brake disc 11. When decelerating, the first lining 12 and the second lining 13 hold the brake disc 11 tightly. The brake 1 includes a cylinder 17, a piston 16 is arranged in the cylinder 17, a first lining 12 is arranged at the end of the piston 16, and a second lining 13 is also arranged in the cylinder 17. A space for installing the brake disc 11 is reserved between the first lining 12 and the second lining 13. A sealing ring 15 is also installed in the cylinder 17. The sealing ring 15 is fixed relative to the cylinder 17, and the piston 16 rubs relative to the piston 16 when it moves. It also includes an elastic sealing dust cover 14, one end of which is fixed on the cylinder 17, and the other end is fixed on the piston 16. When the piston 16 moves and pushes the first lining 12 against the brake disc 11, it will be stretched. During the use of the vehicle, the gap between the first lining 12, the second lining 13 and the brake disc 11 remains unchanged, and is generally set to 0.15-0.25 mm. When the lining is not worn, the elastic sealing dust cover 14 is in a free state. As the lining is worn, the elastic sealing dust cover 14 gradually changes to a stretched state, and the greater the wear of the lining, the greater the stretch of the elastic sealing dust cover 14. When the vehicle decelerates, the blocking force of the brake 1 will increase as the stretch of the elastic sealing dust cover 14 increases, so the starting oil pressure of the master cylinder 2 also increases (when the elastic sealing dust cover 14 is in a free state, the starting oil pressure only needs to push the piston 16 to move, and when the elastic sealing dust cover 14 is stretched, the starting oil pressure also needs to overcome the resetting elastic force of the elastic sealing dust cover 14). The above structure is the basic structure of the existing vehicle brake, and its structure and principle will not be described in detail in this embodiment.

[0018] A method for indirectly monitoring the wear of a brake lining according to this embodiment includes the following steps: S1. Draw a standard change curve; select brake linings with wear amounts of 0%, 25%, 50%, 75%, and 100%, respectively, and draw a standard change curve of vehicle deceleration and output oil pressure according to the brake linings with different wear amounts. The drawn curve is as follows Figure 5 shown.

[0019] S2. Comparison with the standard change curve: During actual driving, the change curve of vehicle deceleration and output oil pressure is compared with the standard change curve to determine the wear amount of the brake lining; S3, wear output; the wear of the brake lining is displayed on the instrument panel for the driver to view in real time.

[0020] S4, wear alarm: set the lining limit wear to 75%. When the lining reaches the limit wear, an alarm signal is issued to prompt the driver to replace the lining in time.

[0021] This solution does not require hardware modification of the vehicle, thus reducing costs. By comparing the deceleration data during vehicle driving with the standard curve, the wear amount of the lining can be detected in real time.

[0022] In this embodiment, the brake is a floating caliper, which is a type of caliper that has only one or two piston cylinders arranged on one side of the brake disc, that is, the elastic sealing dust cover is also arranged on one side with one or two.

[0023] At present, some vehicles use fixed calipers for brakes. This type of caliper has one or two piston cylinders on both sides of the brake disc, so its elastic sealing dust cover is also one or two on both sides of the brake disc. In some embodiments, this type of brake can be used, but the principle of its pipeline pressure change is the same as that of the floating caliper, which will not be described in detail in this embodiment.

[0024] Embodiment 2 This embodiment is aimed at vehicles using hydraulic brakes, and the brake control system of the vehicle has the ability to monitor pipeline pressure.

[0025] like Figure 5 As shown in the standard change curve, the y-axis is the vehicle deceleration, the unit is m / s 2 , the x-axis is the master cylinder oil pressure, the unit is bar. Curve 21 is the change curve when the brake lining wear is 0%, curve 22 is the change curve when the brake lining wear is 25%, curve 23 is the change curve when the brake lining wear is 50%, curve 24 is the change curve when the brake lining wear is 75%, and curve 25 is the change curve when the brake lining wear is 100%.

[0026] Some nodes of curve 21 are: x 2 10 18 29 37 y 0 1 2 3 4 Some nodes of curve 22 are: x 4 12 19 29.4 37.2 y 0 1 2 3 4 Some nodes of curve 23 are: x 6 14 20 29.6 37.4 y 0 1 2 3 4 Some nodes of curve 24 are: x 8 16 21 29.8 37.6 y 0 1 2 3 4 Some nodes of curve 25 are: x 10 18 22 30 37.8 y 0 1 2 3 4 The above curve is the standard variation curve. When the vehicle is braking during normal driving, the in-vehicle controller will compare the current braking deceleration and oil pressure curve with the standard curve to obtain the current lining wear. For example, the curve point captured during braking is: deceleration 1m / s 2, oil pressure 15bar, it can be concluded that the current wear of the lining is between 50% and 75%. In order to improve the detection accuracy, the preset model curve can also be used to simulate each 5% or 1% wear of the lining as a curve, so as to perform a more accurate simulation calculation of the wear of the lining.

[0027] During use, the alarm value of the lining can also be preset, such as setting the limit wear of the lining to 75%. When the measured brake deceleration and oil pressure curve point value has crossed curve 24 (i.e., is located to the right of it), an alarm is issued to remind the driver to replace the lining in time.

[0028] The above curves mainly illustrate that in the initial stage of the deceleration-oil pressure curve, the slopes of curves 21, 22, 23, 24, and 25 gradually increase.

[0029] The intersection points of curves 21, 22, 23, 24, and 25 are basically the same point, until they finally converge into one curve in the second half of the curve. When the oil pressure of the master cylinder is large enough (about > 30 bar, this value is for reference, because the specific value of different vehicles is related to the vehicle parameters and brake system parameter settings), the reaction force generated by the deformation of the elastic sealing dust cover 14 can be ignored, so the deceleration-oil pressure curve of the latter section tends to be consistent.

[0030] When the driver steps on the brake pedal, the master cylinder piston starts to build pressure (the pressure is P1). At this time, because there is a gap in the disc, the vehicle has not decelerated. When the brake piston pushes the friction plate to tighten the brake disc, the master cylinder pressure is P2 (i.e. Figure 5 The starting pressure of the curve shown, at this time P2>P1).

[0031] The above embodiments do not impose any formal limitations on the shape, material, structure, etc. of the present invention. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are within the protection scope of the technical solution of the present invention.

[0032] In the description of the present invention, it is necessary to understand that the terms "center", "longitudinal", "lateral", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the protection content of the present invention.

[0033] If the words "first", "second", etc. are used in this document to limit components, those skilled in the art should know that the use of "first" and "second" is only to facilitate the description of the present invention and simplify the description. Unless otherwise stated, the above words have no special meaning.

[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein, but these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for indirectly monitoring the wear of a brake lining, characterized in that: The following steps are involved: S1. Draw a standard change curve; replace brake linings with different wear amounts, and draw a standard change curve of vehicle deceleration and output oil pressure according to the brake linings with different wear amounts; S2. Comparison with the standard change curve: During actual driving, the change curve of vehicle deceleration and output oil pressure is compared with the standard change curve to determine the wear amount of the brake lining; S3, wear output; the wear of the brake lining is displayed on the instrument panel for the driver to view in real time.

2. A method for indirectly monitoring brake lining wear according to claim 1, characterized in that: In S1, brake linings with wear amounts of 0%, 25%, 50%, 75%, and 100% are selected respectively.

3. The method for indirectly monitoring brake lining wear according to claim 1, characterized in that: The method further comprises step S4, a wear alarm; according to a preset limit wear amount of the lining, an alarm signal is issued when the limit wear amount of the lining is reached.

4. A method for indirectly monitoring brake lining wear according to claim 3, characterized in that: The preset limit wear of the lining is 75%.

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