Apparatus, system and method for monitoring wear of friction material in drum brake

Abstract

An apparatus for monitoring wear of a friction material in a drum brake system based on relative motion between a regulator and a shaft associated with wear of the friction material, and a system and method for monitoring wear of a friction material are described. Specifically, a monitoring device is presented which comprises a sensor assembly that senses relative movement between an adjuster and a shaft, and a processing unit that associates relative movement data with wear of a friction material. The invention belongs to the field of automobiles, vehicle-mounted electronic equipment and braking and sensing systems.

Description

Technical Field

[0001] The present invention describes an apparatus for monitoring the wear of friction material in a drum brake, and more particularly, the apparatus includes a sensor assembly that senses relative motion associated with the wear of the friction material. The present invention belongs to the fields of automobiles, on-board electronics, brake systems, and sensing. Background Art

[0002] Many vehicles use so-called drum brakes in their braking system, which are found especially in heavy vehicles and on the rear axle of many city vehicles. In general, a drum brake system consists of a brake drum that rotates with the wheel, and when the brake is actuated, the actuator moves an internal mechanism that performs the movement outward from the center of the drum, thereby generating a force that opposes the rotational movement of the axle.

[0003] An embodiment of a drum brake system is shown in Figures 1 to 3. In these systems, when the driver depresses the brake pedal, the brake chamber moves the slack adjuster (or brake ratchet), which rotates the S camshaft. The S cam then moves the two brake shoes toward the brake drum via the inner brake pads. The shoes are provided with friction material, which is intended to generate friction opposing the rotational motion of the axle. This friction material is usually called a brake lining.

[0004] As the driver actuates the brake system, the friction material naturally wears away. This wear can lead to brake system failure or malfunction, putting the life of the driver and everyone on the road the vehicle is traveling on at risk. Therefore, over time, the friction material needs to be replaced.

[0005] Many car manufacturers or brake producers set average times for this maintenance to be performed. There are also many cases where a professional performs a manual inspection of the components, but this takes time and sometimes requires disassembling the entire system to check the health of the friction material.

[0006] Therefore, some solutions have been developed that enable the wear of these friction materials in drum brake systems to be monitored using on-board electronic systems.

[0007] As an example, US2011241866 shows one of these possible device configurations for monitoring a brake system. In US2011241866, two rotary sensors arranged in parallel are used, which work together using the Hall effect. The first sensor is intended to read the clearance generated between the adjuster mechanism and the S camshaft. The second sensor, positioned in an additional structure to remain stationary relative to the shaft, acquires the entire brake stroke. In this way, the data from the two sensors are added and associated with the total stroke of the adjuster. However, this solution requires two sensors to work together to obtain the wear of the lining, and also requires reading the entire stroke of the brake movement, which is not to be confused with the solution of the present invention.

[0008] US2015377311 shows a solution similar to the previous solution, but uses a structure that houses the sensor and keeps it stationary relative to the S camshaft of the drum brake. US2015377311 describes that the sensor is a potentiometer so that as the shaft moves due to the actuation of the brake, the extension of the sensor rotates and in this way the angular displacement can be measured. Again, such an arrangement causes the sensor to read data related to the entire braking process.

[0009] Patent US5253735 shows one or two magnets attached to the S camshaft and a static sensor configured to read the angular position of the magnets. The solution proposed by this patent is similar to those previously mentioned, because in this configuration the sensor is responsible for reading the entire brake actuation process, not just data related to pad wear.

[0010] Expired patent PI 9608527-4 shows a device for indicating brake lining wear. This solution uses a magnetically coded disc divided into three sectors and a cover that accommodates sensors in different positions. The disc is attached to the shaft and the sensor remains stationary to read the disc's code when the brake is actuated. Thus, this solution reads the entire brake actuation process.

[0011] Document BR 11 2013 024583-2 shows a more specific construction of the structure that houses the sensor. This structure is a disc containing a protrusion, wherein such a protrusion is aligned with a groove formed in another structure fixed to the S camshaft. This structure facilitates the assembly of the device into the brake system. However, the sensor remains stationary relative to the magnet that rotates along the S camshaft.

[0012] In this regard, it can be noted that none of the solutions mentioned relates to the teaching of the present invention. The proposed document aims at monitoring the wear of the friction material from a fixed structure that reads the entire braking process without being able to verify only the wear caused to the material.

[0013] In this sense, the aim is to develop solutions that identify the movements of the brake system that are directly related to the wear of the friction material, thus providing efficiency and precision in monitoring the wear of the friction material.

[0014] Therefore, it can be inferred from the literature studied that no document was found to foreshadow or suggest the teaching of the present invention, and therefore the solution proposed herein is novel and inventive compared to the prior art. Summary of the invention

[0015] The present invention thus solves the problems of the prior art by monitoring the wear of the friction material based on the relative movement between the adjuster and the shaft, thereby directly correlating this relative movement with the wear of the friction material. For this purpose, the wear monitoring is performed by a monitoring device comprising a sensor assembly that senses this relative movement and a processing unit that correlates data about the relative movement with the wear of the friction material. The present invention thus improves vehicle safety by providing more accurate wear monitoring, thereby contributing to preventive maintenance and durability of the friction material and, therefore, to the reliability of the operation of the braking system.

[0016] Therefore, in the first object, the present invention proposes a device for monitoring the wear of friction material in a drum brake system, wherein the brake system includes a regulator (4) that moves the shaft (5) of the brake drum (1), and the monitoring device includes: a sensor assembly, which senses the relative movement between the regulator (4) and the shaft (5), and the sensor assembly is positioned in the brake system; and a processing unit (17) that communicates with the sensor assembly to obtain data about the relative movement between the regulator (4) and the shaft (5), and the data about the relative movement between the regulator (4) and the shaft (5) is associated with the wear of the friction material.

[0017] In a second object, the present invention proposes a system for monitoring the wear of friction material in a vehicle equipped with a drum brake system, the drum brake system comprising an adjuster (4) that moves the shaft (5) of the brake drum (1), wherein the monitoring system comprises a device for monitoring the wear of friction material as described above, and a device for storing at least one movement data related to the wear of friction material; wherein a processing unit (17) of the monitoring device associates the data of the relative movement between the adjuster (4) and the shaft (5) with the said movement data related to the wear of friction material.

[0018] In the third object, the present invention provides a method for monitoring the wear of friction material in a drum brake system, wherein the drum brake system includes a regulator (4), which moves the shaft (5) of the brake drum (1) starting from the step of actuating the drum brake system, wherein the monitoring method includes the following steps: sensing the relative movement between the regulator (4) and the shaft (5) through a sensor component; obtaining data about the relative movement between the regulator (4) and the shaft (5) through a processing unit (17) that communicates with the sensor component; and correlating the data about the relative movement between the regulator (4) and the shaft (5) with the wear of the friction material through the processing unit (17).

[0019] These and other objects of the present invention will be immediately understood by those skilled in the art and will be described in detail below. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to better define and clarify the content of this patent application, the following figure is proposed:

[0021] 1 to 3 show different views of a schematic diagram of a conventional drum brake system.

[0022] Figure 4 The monitoring process of the present invention is illustrated by way of example, and a flow chart is shown.

[0023] The assembly of Figure 5 shows a first embodiment of the monitoring device of the present invention.

[0024] Figure 5a A view showing an embodiment of a structure (9) fixed to the regulator (4).

[0025] Figure 5b Shows Figure 5a The structural member (9) has no base (10) and protrudes from the housing (11).

[0026] Figure 5c A front view of an embodiment of the housing (11) is shown.

[0027] Figure 5d A rear perspective view of the housing (11) is shown.

[0028] Figure 5e A perspective view of the housing (11) is shown, highlighting the head (12) fitted between the shaft (5) and the housing (11).

[0029] Figure 5f A perspective view of the housing (11) is shown, highlighting the wall (115) positioned inside the housing (11).

[0030] Figure 5gA longitudinal cross-sectional view is shown showing the sensor module (14) positioned in the housing (11).

[0031] Figure 5h Shows the rotation to Figure 5g The location shown in Figure 4 g sensing module (14).

[0032] The assembly of Figure 6 shows a second embodiment of the monitoring device of the present invention.

[0033] Figure 6a A view showing an embodiment of a second reactor in relation to a braking system is shown.

[0034] Figure 6b A front view of the regulator (4) of the embodiment with a second reactor is shown.

[0035] Figure 6c An isolated view of an embodiment of the structure (9) is shown, highlighting the structure (9) being secured to the regulator (4) via the support (92).

[0036] Figure 6d A detailed view of the device of the invention is shown, highlighting the housing (11).

[0037] Figure 6e A view showing an embodiment of a head (12) coupled to a shaft (5) and a magnet (13) fixed to the head (12).

[0038] Figure 6f A rear view of an embodiment of the structural member (9) is shown, highlighting the interface (115) of the housing (11).

[0039] Figure 6g A front view of an embodiment of a structure (9) is shown, highlighting the housing (11) secured to the base (10).

[0040] Figure 6h A view of an embodiment of the housing (11) is shown, highlighting the interface (115).

[0041] The assembly of Figure 7 shows a third embodiment of the monitoring device of the present invention.

[0042] Figure 7a A view is shown presenting an embodiment of the device of the present invention.

[0043] Figure 7b A separate view of the regulator (4) and the described embodiment of the device is shown.

[0044] Figure 7c An exploded view of an embodiment of the apparatus of the present invention is shown.

[0045] Figure 7d Shown in more detail Figure 7c Exploded view shown in .

[0046] Figure 8 An embodiment is shown in which the magnet (13) is rotated relative to the sensing module (14).

[0047] Fig. 9 A schematic diagram showing the magnet (13) relative to the sensor module (14) and the distance between the two.

[0048] Fig.10 A graphical display resulting from a test using the apparatus of the present invention is shown.

[0049] Fig.11 A graph showing brake wear versus lining thickness obtained from tests using the apparatus of the present invention is shown. DETAILED DESCRIPTION

[0050] Embodiments of conventional drum brake systems are illustrated in the set of Figures 1 to 3. In these systems, a brake drum (1) rotates with the wheel and when the driver depresses the pedal, a brake chamber (2) moves a rod (3) which is fixed to a slack adjuster (4). The adjuster (4) is mechanically associated with a shaft (5) of the drum brake. An "S" shaped cam (6) (commonly referred to as an S-cam) is arranged at the opposite end of the shaft (5), wherein the S-cam (6) moves a brake shoe (7) towards the brake drum (1). The brake shoe (7) is provided with a friction material (8) which comes into contact with an inner portion of the brake drum (1) generating a friction force opposing the rotational movement of the wheel.

[0051] Due to the friction generated during the braking process, the lining (8) wears and a gap may appear between the friction material (8) and the drum (1). The automatic adjuster (4) has the function of correcting this slack between the brake lining (8) and the brake drum (1) so that the distance between them remains constant and consistent, that is, regulating the proximity of these components when the brake system returns to the initial position. Therefore, the adjuster (4) can improve braking safety because the lining (8) will be in the ideal position relative to the brake drum (1) to restart the braking process when necessary.

[0052] It is worth noting that the brief introduction of a conventional schematic diagram of a drum brake system should not limit the inventive concept proposed in this patent application. Furthermore, the known solution for monitoring the wear of the friction material (8) in a brake system is to electronically sense the full actuation of the regulator (4) to the shaft (5), using a sensor fixed relative to the shaft (5) to read the full rotation of the shaft (5). In contrast, the present invention monitors the wear of the friction material (8) based on the relative movement between the regulator (4) and the shaft (5).

[0053] Therefore, in the first object, the present invention proposes a device for monitoring the wear of friction material in a drum brake system, wherein the brake system includes a regulator (4) that moves the shaft (5) of the brake drum (1), and the monitoring device includes: a sensor component, which senses the relative movement between the regulator (4) and the shaft (5), and the sensor component is positioned in the brake system; a processing unit (17), which communicates with the sensor component to obtain data about the relative movement between the regulator (4) and the shaft (5), and the data about the relative movement between the regulator (4) and the shaft (5) is associated with the wear of the friction material.

[0054] Generally speaking, when part P moves relative to observer O, observer O will perceive relative motion between observer O and part P. For the present invention, the relative motion of interest occurs between adjuster (4) and shaft (5), which is an angular change. The relative motion occurs because: each time the friction material is worn during braking, the shaft (5) rotates within the adjuster (4) to seek a favorable position to maintain sufficient slack between the friction material (8) and the brake drum (1). This rotation is provided by the internal mechanism of the automatic adjuster (4) when the automatic adjuster (4) senses that the friction material (8) has been worn. In one embodiment, the relative angular motion between the adjuster (4) and shaft (5) is proportional to the wear of the friction material (8). In this case, the present invention provides a sensor assembly in one embodiment that can read this motion generated between the S camshaft and the adjuster.

[0055] The processing unit (17) thus correlates the relative movement data between the adjuster (4) and the shaft (5) with the movement data relating to the wear of the friction material.

[0056] For this purpose, the monitoring device of the present invention has a sensor assembly positioned in the brake system to sense the relative movement between the regulator (4) and the shaft (5). The relative movement is converted into relative movement data between the regulator (4) and the shaft (5), which can be read by a processing unit (17). For the purpose of the present invention, the processing unit (17) is any electronic component capable of following a set of predefined instructions, reading movement data, performing processing of the data and data association. In one embodiment, the processing unit (17) is a microcontroller or a microprocessor.

[0057] Therefore, the conversion of the relative motion into data is performed by a sensor assembly that generates the relative motion data between the regulator (4) and the shaft (5). In one embodiment, the sensor assembly generates the relative motion data between the regulator (4) and the shaft (5) based on the angular changes associated with the relative motion between the regulator (4) and the shaft (5). In one embodiment, the data is generated from the linear changes associated with the relative motion between the regulator (4) and the shaft (5). In this latter embodiment, the linear motion is mechanically generated by the sensor assembly itself, converting the angular motion performed by the relative motion between the regulator (4) and the shaft (5).

[0058] In one embodiment, the conversion is provided by a sensor assembly to sense the relative movement between the actuator (4) and the shaft (5). Alternatively, the sensing is a physical sensation obtained by mechanical, magnetic and / or electronic means.

[0059] In view of this, the sensor assembly has a first reactor associated with the shaft (5); and a second reactor associated with the brake system. In this way, the second reactor senses the movement of the first reactor, so that the movement corresponds to the relative movement between the regulator (4) and the shaft (5).

[0060] To this end, a second reactor is positioned in one of the brake system components (brake pedal, brake chamber (2), rod (3), regulator (4), etc.) so that the second reactor senses the movement of the first reactor based on changes associated with the relative movement between the regulator (4) and the shaft (5).

[0061] In one embodiment, the relative motion between the regulator (4) and the shaft (5) is related to c The change is an angular change between the first reactor and the second reactor. In one embodiment of the angular change associated with the relative movement between the regulator (4) and the shaft (5), the second reactor is associated with the regulator (4).

[0062] Thus, the sensor assembly senses the relative movement between the adjuster (4) and the shaft (5) and generates data about the relative movement. Thus, the processing unit (17) communicates with the sensor assembly, receives the data about the relative movement between the adjuster (4) and the shaft (5), and correlates it with the wear of the friction material.

[0063] Furthermore, the device for monitoring according to the invention comprises a structural element (9) provided with a housing (11) and a base (10) associated with a regulator (4). In one embodiment, the structural element (9) accommodates a processing unit (17). In another embodiment, the second reactor is a sensor module (14) which is positioned in the structural element (9) by means of the housing (11).

[0064] In one embodiment, the housing (11) of the structure (9) is fixed to the base (10) so that the second reactor is coordinated with the movement of the regulator (4). In another embodiment, the housing (11) of the structure (9) has an interface between the first reactor and the second reactor. In this way, the housing interface (11) provides a predetermined distance separating the first reactor and the second reactor for sensing the relative movement between the regulator (4) and the shaft (5). Thus, the invention facilitates the absorption of possible axial differences associated with the association between the components of the device, since, in addition to the mechanical wear of these components, highly variable dimensional tolerances are foreseen during the manufacturing process of such components.

[0065] Furthermore, the first reactor is coordinated with the movement of the shaft (5) and is positioned next to the housing interface (11) of the structure (9). In an embodiment in which the first reactor is integrated with the movement of the shaft (5) and the second reactor is integrated with the movement of the regulator (4), the change associated with the relative movement between the regulator (4) and the shaft (5) is angular between the first reactor and the second reactor.

[0066] Alternatively, in one embodiment, the change associated with the relative movement between the regulator (4) and the shaft (5) is another angular change. In this embodiment, the first reactor is a sector of the shaft (5), and the second reactor is an arm connected to the regulator (4) and arranged on the sector of the shaft (5), wherein the arm senses the movement of the sector of the shaft (5), which is associated with the relative movement between the regulator (4) and the shaft (5).

[0067] In a second object, the present invention proposes a system for monitoring the wear of friction material in a vehicle equipped with a drum brake system, the drum brake system comprising an adjuster (4) that moves the shaft (5) of the brake drum (1), wherein the system for monitoring comprises a device for monitoring the wear of friction material as defined above, and a device for storing at least one movement data related to the wear of friction material; wherein the processing unit (17) of the monitoring device associates the data of the relative movement between the adjuster (4) and the shaft (5) with the movement data related to the wear of friction material.

[0068] In one embodiment, the device for storing motion data related to the wear of the friction material assembles a history of the operation of the brake system for the vehicle driver to check the health of the friction material (4). In addition, the system for monitoring can be installed in any S-cam drum brake system as a kit for monitoring, measuring and identifying the wear of the lining (8), thereby avoiding accidents by obtaining the wear more accurately. In one embodiment, the system of the present invention is implemented in a drum brake during the manufacturing process of the drum brake. In another embodiment, the system is installed in a drum brake that has been manufactured before.

[0069] In this way, when the brake is actuated, the sensor assembly is able to monitor the relative movement between the adjuster (4) and the shaft (5). This relative movement is caused by the wear of the friction material (8), and as previously shown, the adjuster (4) tends to correct the existing slack between the friction material (8) and the brake drum (1). By detecting the relative movement between the adjuster (4) and the shaft (5), this arrangement of the device for monitoring of the invention prevents the sensor assembly from capturing any interference caused by slack between the mechanical parts of the brake system, because a change in position between the shaft (5) and the adjuster (4) means that the friction material (8) is worn.

[0070] In one embodiment, the communication between the processing unit (17) and the sensor assembly is wireless communication, wherein the processing unit (17) is located on the chassis of the vehicle and the sensor assembly is located on the brake system. In another embodiment, the communication between the processing unit (17) and the sensor assembly is wired communication.

[0071] In another embodiment, the processing unit (17) communicates with a device that makes friction material wear data available to a user. The data can be made available to the vehicle driver via an on-board display or via a smartphone. The data can also be made available to a remote server.

[0072] Furthermore, the device for monitoring communicates with a remote station, wherein the remote station receives motion data related to wear of the friction material. In one embodiment, the remote station manages a fleet of vehicles, and thus the invention improves the reliability of the fleet by monitoring the wear of the respective linings (8) of the vehicles.

[0073] In the third object, the present invention provides a method for monitoring the wear of friction material in a drum brake system, wherein the drum brake system includes a regulator (4), which moves the shaft (5) of the brake drum (1) starting from the step of actuating the drum brake system, wherein the method for monitoring includes the following steps: sensing the relative movement between the regulator (4) and the shaft (5) through a sensor component; obtaining data about the relative movement between the regulator (4) and the shaft (5) through a processing unit (17) that communicates with the sensor component; and correlating the data about the relative movement between the regulator (4) and the shaft (5) with the wear of the friction material through the processing unit (17).

[0074] In one embodiment, the method is implemented by the previously described apparatus for monitoring. In one embodiment, the method follows Figure 4 Flowchart illustrated in FIG.

[0075] Thus, the brake system is actuated by the brake pedal, thereby moving the rod (3), which moves the adjuster (4), which in turn moves the shaft (5). Naturally, the friction material (8) wears, thereby creating slack between the friction material (8) and the brake drum (1), wherein the adjuster (4) compensates for the slack.

[0076] Therefore, the brake system exhibits a relative movement between the regulator (4) and the shaft (5). Therefore, the method of the invention has the step of sensing the relative movement between the regulator (4) and the shaft (5) by means of a sensor assembly.

[0077] Finally, the method of the invention comprises a step of converting the relative movement between the regulator (4) and the shaft (5) into data on the relative movement between the regulator (4) and the shaft (5) by means of a sensor assembly, wherein the data on the relative movement are converted according to a change in movement of the first reactor sensed by the second reactor. In one embodiment, the change in movement is angular. Furthermore, the second reactor is associated with a braking system and the first reactor is associated with the shaft (5).

[0078] Then, the method is implemented by acquiring the relative movement data between the regulator (4) and the shaft (5) by the processing unit (17). Using the relative movement data, the processing unit (17) performs a correlation between the relative movement data between the regulator (4) and the shaft (5) and the wear of the friction material (8).

[0079] Thus, the method of the present invention provides a more accurate correlation with the ongoing wear of the friction material (8). In one embodiment, the correlation is between the relative motion data between the adjuster (4) and the shaft (5) and the motion data related to the wear of the friction material.

[0080] On this basis, wear data is made available to the user to enable him or her to obtain monitoring of the friction material (8). The data may be made available to an on-board display (e.g. an on-board computer), the user's smartphone, a remote server or a combination of these alternatives.

[0081] The invention is applicable to any drum brake system, but also to disc brakes, whatever the type of vehicle, be it a city vehicle, a passenger vehicle, a freight vehicle, a road implement, etc.

[0082] The embodiment shown here is intended to illustrate only one of the many ways to implement the invention and not to limit its scope.

[0083] Example 1

[0084] The device of the invention is developed for application in a drum brake system. A conventional drum brake system is illustrated in the set of Figures 1 to 3 .

[0085] The device for monitoring the embodiment is implemented Figure 4 For this purpose, the device of the embodiment described has a sensor assembly and a processing unit (17), which is positioned in the brake system by means of a structure (9), which has a base (10) screwed to the regulator (4) through a hole (91), such as Figure 5a As shown in .

[0086] Remove the base (10), Figure 5b The housing (11) is shown attached directly to the shaft (5). Figure 5c A front view of the housing (11) covered by a cover is shown, which is screwed to close the housing (11) to facilitate maintenance of the device.

[0087] Figure 5dA rear view of the housing (11) is shown, highlighting the head (12) that allows the housing (11) to be directly coupled to the shaft (12), wherein the head (12) is assembled in a U-shaped protrusion formed on the surface of the housing (11). The U-shaped geometry allows the sensors in the head (12) and the housing (11) to be centrally aligned, and also prevents the housing (11) from moving away from the head (12) because the head (12) has an assembly that acts as a drawer. Nevertheless, this assembly allows relative angular movement between the head (12) in coordination with the shaft (5) and the housing (11) in coordination with the structural member (9), which is in turn fixed to the frame of the regulator (4). Therefore, the head (12) has a threaded end for coupling to the shaft (5).

[0088] In this way, Figure 5e As can be seen, the head (12) defines a first reverberator that cooperates with the movement of the shaft (5). In addition, the housing (11) has a protrusion (112) on its periphery that fits into the base (10), blocking the housing (11) from moving together with the shaft (5), thereby keeping the housing (11) and the regulator (4) in coordination. In addition, since the protrusions (112) are arranged in an uneven manner on the periphery of the housing (11), the protrusions (112) prevent improper assembly of the pre-arranged position.

[0089] In addition, the housing (11) has an interface (115) between the first reactor and the second reactor accommodated in the housing (11), and a predetermined distance between the first reactor and the second reactor is increased. For example, the second reactor is a sensor module (14), which is a sensor separated from the first reactor together with the head (12) through the interface (115), so that the sensor senses the movement of the first reactor.

[0090] Thus, the device in the described embodiment includes the concept of the present invention, and is provided with a sensor assembly that senses the relative movement between the regulator (4) and the shaft (5), as exemplified by the different positions of the sensing module (14) relative to the shaft (5), the sensing module (14) being associated with the regulator (4). Thus, the relative movement between the regulator (4) and the shaft (5) is converted into data of the relative movement based on the angular variation between the sensing module (14) and the magnet (13) coupled to the head (12).

[0091] Finally, the processing unit (17) receives the data of the relative movement and correlates the data with the wear-related movement data. For example, the processing unit (17) is also accommodated in the housing (11).

[0092] Example 2

[0093] like Figures 6a to 6cAs shown, the moving device of the embodiment has a structure (9) which is fixed to the regulator (4) by a support (92) surrounding the regulator (4) so ​​as to adapt to the shape of the regulator (4). In addition, the support (92) is attached to the regulator (4).

[0094] For the arrangement of the components of the device of the present invention, Figure 6d As shown, the structure (9) is a single body or divided into two parts: a base (10) and a housing (11). Therefore, the structure (9) which is a single body or divided into two parts is compatible to be fixed with multiple regulators (4).

[0095] Thus, the base (10) is screwed onto the support (92) by means of three fastening elements (91). Thus, the housing (11) is fitted into the interior of the base (10) and locked by means of projections (112) arranged on the periphery of the base and in contact with the interior of the housing (11).

[0096] In order to sense the relative movement between the regulator (4) and the shaft (5), the sensor assembly in the embodiment is composed of a first reactor and a second reactor, wherein the first reactor is a magnet (13) and the second reactor is a sensor (14), and the sensor (14) uses the Hall effect principle to read the angle change caused by the relative movement between the shaft (5) and the regulator (4). Therefore, the relative movement between the regulator (4) and the shaft (5) is converted into relative movement data.

[0097] Still in Figure 6d In the embodiment, the housing (11) accommodates the sensor (14). In this way, the sensor (14) cooperates with the housing (11) fixed to the structure (9), wherein the sensor (14) is arranged at the moving end of the housing (11), inside the housing (11), so that the sensor (14) can move axially in the housing (11), but the protrusions of the housing (11) prevent the rotation of the sensor (14) relative to the regulator (4), and the uneven arrangement of the protrusions prevents assembly outside the pre-arranged position.

[0098] Therefore, the housing (11) accommodates the sensor (14) so ​​that the sensor (14) is within a predetermined distance relative to the magnet (13) fixed to the top end of the shaft (5) of the S cam (6), such as Figure 6e Furthermore, the housing part (12) fixes the magnet (13) to the shaft (5), so that the magnet (13) rests on the movable end of the housing (11) and is free to rotate relative to the sensor (14) fixed to the regulator (4). Thus, the thickness of the movable end of the housing (11) allows the predetermined distance between the magnet (13) and the sensor (14) to be met.

[0099] also, Figure 6fA housing (11) is shown, in which the sensor (14) can be axially moved within the housing (11) through the movable end of the housing (11) when housed, thereby compensating for axial differences during the assembly of the device and mainly maintaining a predetermined distance between the sensor (14) and the magnet (13) in order to correctly read the relative movement between the automatic regulator (4) and the shaft (5). Figure 6f Also shown is a sealing ring beside the movable end of the housing (11) to seal against the housing part (12).

[0100] Figure 6g The housing (11) is shown coupled to the base (10), forming the structural member (9). Furthermore, the base (10) is fixed to the regulator (4) by means of fastening elements arranged at the periphery of the base (10), eliminating the need for the use of the support member (92). To close the base (10), a cover is fixed to the housing (11).

[0101] Figure 6h The housing (11) is shown removed from the base (10), wherein a spring adjusts the axial distance between the sensor (14) and the magnet (13), eliminating the need for adapters such as washers. In order to accommodate the sensor (14) in the housing (11) connected to the battery and the embedded circuit of the sensor (14), a resin covering at least the sensor (14) is used for insulation. In addition, the housing (11) has an opening to allow replacement of the battery.

[0102] Furthermore, the embedded circuit of the sensor (14) has a radio module allowing wireless communication to communicate with a control unit fixed to the chassis, or to supply power and receive signals via a cable. In this way, the sensor (14) sends data on the relative movement between the regulator (4) and the shaft (5) to the processing unit (17).

[0103] In this embodiment, the processing unit (17) is attached to a surface opposite to the surface that houses the sensor (14). This allows wear monitoring to be performed on the vehicle itself, making the data available to the driver as well as to a server or remote user. The processing unit (17) is equipped with on-board intelligence that executes an algorithm. The algorithm correlates previously stored data with the data read by the sensor (14). The previously stored data is the relative angle change between the regulator (4) and the shaft (5) associated with the wear data. Accordingly, the wear data is data on the wear of the brake drum (1), the wear of the lining (8) of excess material, and the wear of the rollers measured in excess next to the shaft (5).

[0104] Example 3

[0105] like Figure 7aAs illustrated, the monitoring device of the embodiment is coupled to a drum brake system. The structure (9) is directly coupled to the automatic adjuster (4) so ​​that when the automatic adjuster (4) is moved by the rod (3) of the brake chamber (2), the structure (9) follows its rotational movement. Figure 7b Shown are separate views of the automatic regulator (4) and the structure (9) fixed to it, as well as the processing unit (17).

[0106] from Figure 7c As can be seen in the figure, the structural member (9) is provided with a base (10) and a housing (11). The base (10) is responsible for fixing the structural member (9) to the automatic regulator (4). The base (10) has a lug for fixing the structural member (9) to the automatic regulator (4), wherein the fixing can take place by permanent or non-permanent fixing elements.

[0107] In this embodiment, the base (10) has two layers, the first layer is used to fix with the regulator (4), and the second layer is used to fix with the housing (11), wherein the radius of the second layer is smaller than the radius of the first layer. On the second layer, protrusions for fixing with the housing (11) are formed, wherein these protrusions are formed along the outer edge of the second layer. The protrusions are fitted into the cavities formed in the outer edge of the housing (11), so that the two are geometrically compatible.

[0108] exist Figure 7d , an exploded view of the device in more detail, shows that the sensor (14) is coupled to the housing (11). The housing (11) has a surface for receiving the sensor (14) so ​​that the sensor (14) is within a predetermined distance relative to the magnet (13), which is fixed to the top of the shaft (5) of the S cam (6).

[0109] In the configuration of this embodiment, the magnet (13) is fixed to the top of the shaft (5) by means of a plastic housing component (12), which also has the function of keeping the magnetic field away from the metal material of the shaft to prevent it from affecting the data collected. In this way, the magnet (13) is free to rotate relative to the sensor (14) fixed to the cover (11). Therefore, in this configuration, the sensor (14) can read the rotational movement of the shaft (5) relative to the automatic regulator (4) itself, because the sensor (14) moves with the automatic regulator (4).

[0110] Still in Figure 7d In FIG. 1 , it can be seen that the processing unit (17) is attached to the surface opposite to the surface housing the sensor (14). This allows wear monitoring to be performed on the vehicle itself, making the data available to the driver as well as a server or remote user.

[0111] Example 4

[0112] The AS5600 Hall Effect sensor was also used for testing and concept verification. Of course, other sensor models can also be used to implement the concepts proposed by the present invention, so the embodiments given here do not limit its scope.

[0113] On this basis, Figure 8 and Fig. 9 (Taken from the AS5600 component data sheet to illustrate its operation) shows an embodiment of the angle variation of the magnet (13) relative to the sensor (14) and the recommended distance range between the magnet (13) and the sensor (14). This distance range is taken into account when assembling the sensor (14) to the housing (11) of the structural member (9). In this embodiment, the interface (115) between the sensor and the magnet is a partition of the housing (11).

[0114] In these tests, Fig.10 As shown, different parameters can be obtained from the collected data regarding the percentage of wear of the lining (8) and the relative angular movement between the adjuster (4) and the shaft (5). Fig.11 The test results of lining wear [%] and lining thickness [mm] can be verified in.

[0115] A person skilled in the art will appreciate the knowledge presented herein and will be able to reproduce the invention in the embodiments presented as well as in other variations and alternatives, covered by the scope of the following claims.

Claims

1. A device for monitoring the wear of friction material in a drum brake system, wherein the brake system comprises an adjuster (4) for moving a shaft (5) of a brake drum (1), the monitoring device being characterized in that it comprises: a. a sensor assembly, the sensor assembly sensing the relative movement between the regulator (4) and the shaft (5), wherein the sensor assembly is positioned in the brake system; as well as b. A processing unit (17) communicating with the sensor assembly to obtain data on the relative movement between the adjuster (4) and the shaft (5), the data on the relative movement between the adjuster (4) and the shaft (5) being associated with the wear of the friction material.

2. The device for monitoring according to claim 1, characterized in that The relative movement between the adjuster (4) and the shaft (5) is an angular change, wherein the processing unit (17) performs a correlation of the relative movement data between the adjuster (4) and the shaft (5) with movement data related to the wear of the friction material.

3. The device for monitoring according to claim 1, characterized in that The sensor assembly comprises: a. a first reactor associated with the shaft (5); and b. A second reactor associated with the braking system, which reactor senses the movement of the first reactor so that the movement corresponds to the relative movement between the regulator (4) and the shaft (5).

4. The device for monitoring according to claim 3, characterized in that The second reactor is associated with the regulator (4).

5. The device for monitoring according to claim 3, characterized in that The second reactor comprises a sensor module (14) positioned in a structure (9), wherein the structure (9) comprises a base (10) associated with the regulator (4) and a housing (11) accommodating the sensor module (14).

6. The device for monitoring according to claim 5, characterized in that The housing (11) of the structure (9) is fixed to the base (10) and includes an interface between the first reactor and the second reactor.

7. The device for monitoring according to claim 6, characterized in that The first reactor cooperates with the movement of the shaft and is positioned beside the interface of the housing (11) of the structure (9).

8. A system for monitoring the wear of friction material in a vehicle provided with a drum brake system, said drum brake system comprising an adjuster (4) for moving a shaft (5) of a brake drum (1), said monitoring system being characterized in that it comprises: a. A device for monitoring wear of a friction material as defined in claim 1; as well as b. a device for storing at least one motion data associated with wear of the friction material; The processing unit (17) of the monitoring device converts the data of the relative movement between the regulator (4) and the shaft (5) into movement data related to the wear of the friction material.

9. The system for monitoring according to claim 8, characterized in that The monitoring device is in communication with a remote station, wherein the remote station receives motion data related to wear of the friction material.

10. A method for monitoring the wear of friction material in a drum brake system, the drum brake system comprising an adjuster (4) which moves a shaft (5) of a brake drum (1) starting from a step of actuating the drum brake system, the monitoring method being characterized in that it comprises the following steps: a. sensing the relative movement between the regulator (4) and the shaft (5) by positioning a sensor assembly in the braking system; b. acquiring data on the relative movement between the regulator (4) and the shaft (5) by a processing unit (17) communicating with the sensor assembly; and c. Correlating the data on the relative movement between the adjuster (4) and the shaft (5) with the wear of the friction material by the processing unit (17).

11. The method for monitoring according to claim 10, characterized in that: The association is an association of the relative movement data between the regulator (4) and the shaft (5) with the movement data associated with the wear of the friction material.

12. The method for monitoring according to claim 10, characterized in that: It comprises the step of converting the relative movement between the regulator (4) and the shaft (5) into data about the relative movement between the regulator (4) and the shaft (5) by means of the sensor assembly, wherein the relative movement is converted according to the movement change of a first reactor associated with the shaft (5), the change being sensed by a second reactor.

13. The method for monitoring according to claim 12, characterized in that: The second reactor is associated with the braking system.

14. The method for monitoring according to claim 10, characterized in that: Data regarding the relative movement between the adjuster (4) and the shaft (5) is correlated to the ongoing wear of the friction material.

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