SYSTEM AND METHOD FOR DETECTING OVERLOAD, WEAR AND / OR FAILURE OF A BALL JOINT

Abstract

System for detecting possible failure and / or sufficient wear of a ball joint, the system comprising: a ball housing (2); a ball ring (20) received in the ball housing (2); a ball head (26) integrally fixed to one end of a ball stud (28); wherein the ball head (26) of the ball stud (28) is received and held in the ball housing (2), the ball ring (20) separating the ball head (26) from the ball housing (2), and an inwardly facing surface (24) of the ball ring (20) engaging with the ball head (26) such that the ball head (26) is movable relative to the ball housing (2); a detection component supported by the ball ring (20) such that the detection component is initially spaced at a desired distance from the inwardly facing surface (24) of the ball ring;and wherein the detection component engages with an outer surface (48) of the ball head (26) upon either failure or sufficient wear of the ball ring (20) and generates an indicator signal that alerts a driver and indicates that maintenance of the ball joint is required, characterized in that the detection component comprises a structure (44) with multiple ribs and / or an electrical circuit with multiple forks (46), wherein the multiple ribs and / or forks (46) are housed in the ball ring (20) and substantially surround a periphery of the ball head (26).

Description

AREA OF INVENTION

[0001] The present invention relates to a system and a method for detecting overload, wear and / or failure of a ball joint. BACKGROUND OF THE INVENTION

[0002] Ball joints have long been used in motor vehicles and are commonly found in vehicle suspension and steering systems. They are used to connect two or more components; for example, wheel hubs are generally connected to the rest of the suspension via a ball joint, allowing these components to move relative to each other in different directions. Ball joints essentially consist of a metal ball supported within a cage or socket. Typically, the space between the ball and the socket is filled with grease to reduce wear, and a rubber seal is usually placed over the ball joint to prevent the ingress of water and dirt.Sometimes rubber seals fail, allowing water, dirt, and / or other contaminants to enter the ball joint, and grease can also leak out, further reducing its lifespan. Ball joints can also fail due to impact forces, such as when the wheel hits a pothole or curb. Corrosion, wear, damage, and / or failure of ball joints often manifests itself audibly and / or inaudibly. Signs that a typical ball joint may be failing include clacking, popping, or cracking noises. These noises may develop into a squealing sound while driving, during acceleration, and / or when driving over bumps. Another indication of ball joint failure can be a dull thumping sound coming from the suspension when driving over bumps.Ball joints that have lost their grease or other lubricant can be identified by a drastic increase in friction, which causes the steering to stick or become difficult.

[0003] The effects of ball joint failure can be dangerous because the wheel's steering angle is no longer limited, resulting in a loss of vehicle control. This lack of control over the wheel's steering angle can lead to damage to the tire and other vehicle components.

[0004] Over the past decade, numerous improvements in driving technology have been achieved through advancements in electronic and intelligent systems. While these systems enhance vehicle operation, they also tend to reduce the audible and inaudible effects of factors such as corrosion, wear, damage, and / or failure of ball joints, thus significantly complicating the detection of worn or damaged ball joints. It is possible that a driver may not even notice a damaged ball joint and therefore continue to drive the vehicle in this condition.

[0005] From DE 10 2008 041 050 A1, a method for measuring the wear of a ball-and-socket joint is known. For this purpose, a magnetic field parameter is measured with a magnetic field sensor at a time when either a force acts on a ball stud of a ball joint or no force acts on it. The measured magnetic field parameter is then transmitted from the magnetic field sensor to a control unit for evaluation. By evaluating the measured sensor signal, the wear state of the ball-and-socket joint can be determined. In particular, the ball-and-socket joint comprises a ball stud with a ball that is pivotably and rotatably supported by a ball socket. The ball-and-socket joint includes an angle measuring device with a magnet that is fixed to the ball or the ball socket, and a magnetic field sensor that is fixed to the other element – ​​the ball socket or the ball.The magnetic field sensor measures the strength of the magnetic field generated by the magnet in at least one spatial direction at a first time when the ball joint is under a first load. The magnetic field sensor then measures the strength of the magnetic field generated by the magnet in the same spatial direction at a second time when the ball joint is under a second load. Since the position of the ball relative to the socket depends on the loads acting on the ball joint, the magnetic field strength measurements are then evaluated to determine the wear state of the ball joint with respect to the loads to which it is subjected.Although this ball-and-socket joint may be advantageous for its intended purpose, the sensor merely dictates the position of the ball relative to the socket when the magnet moves relative to the sensor and does not determine the wear or failure of the ball joint.

[0006] US Patent 2004 / 0037619 A1 discloses a ball joint in which a receptacle for mounting an electrode is provided in the outer surface of the ball socket. When the ball socket wears sufficiently at the electrode location, the ball surface comes into direct contact with the electrode. This generates an electrical signal that can be used to indicate wear.

[0007] US Patent 7,695,211 B1 describes a ball joint in which a wear indicator in the form of a metal pin is used. With sufficient wear, the ball joint housing lowers to the point where it comes into contact with the metal pin. During relative movement between the housing and the pin, an audible noise is produced, indicating wear of the ball joint.

[0008] The use of a moisture sensor in a ball joint is known from US patent 2007 / 0059091 A1. BRIEF SUMMARY OF THE INVENTION

[0009] One object of the invention is therefore to provide a system and method for detecting overload, wear, and / or failure of a ball joint. The system detects water ingress, corrosion, wear, damage, failure, and / or overloading of ball joints and informs the driver that the ball joint is suspect and the vehicle should be serviced. Another object of the invention is to detect the ingress of moisture into the ball joint and notify the driver so that remedial action, e.g., replacing the part during servicing, can be taken before the moisture leads to corrosion and wear of the ball joint.

[0010] A further object of the present invention is to provide a ball joint that includes a system for detecting overload, wear, and / or failure of the ball joint. The ball joint comprises a ball stud with a ball head that is received in a ball ring, which in turn is received in a joint housing. The ball ring has an outer surface that aligns with the inwardly facing surface of the joint housing and an inwardly facing surface that substantially matches the shape of the ball head. The ball head is held in position by the ball ring in the joint housing such that the center of the ball is generally fixed in position within the joint housing, and can rotate about its axis of rotation and pivot laterally with respect to the ball housing.

[0011] A further object of the present invention is to provide a system and a method for detecting overload, wear, and / or failure of a ball joint comprising a ball ring with a body formed from a first material. A structure of ribs, teeth, forks, and / or prongs, made from a second material, is enclosed in or attached to a body of the ball ring. The second material is generally harder than the first material from which the body is formed and is intended to produce a noise when it comes into contact with the ball head. Due to the difference in hardness between the first and second materials, the ball ring deforms when a sufficient force is applied to the ball joint, such as when the vehicle encounters a pothole or a curb.This deformation of the structure causes an uneven distribution of contact between the ball ring and the ball head. The contact between the ball head and the harder material of the deformed ball ring leads to loud noises during continued vehicle movement, which in turn signals to the driver that the ball joint may have failed and that vehicle maintenance is required.

[0012] A further object of the present invention is to provide a system and a method for detecting overload, wear, and / or failure of a ball joint, comprising a sensor module that detects these conditions of the ball joint and alerts the driver accordingly. In a variation of the inventive system for detecting overload, wear, or failure of a ball joint, the ball is preferably electrically conductive, and the ball ring is non-conductive. The body of the ball ring comprises an electrical circuit encapsulated within the non-conductive material of the body. The electrical circuit can be configured, for example, as a printed circuit or electrical conductors extending through the body as ribs, teeth, forks, and / or prongs.The electrical circuitry of the ball ring can be deformed by the non-electrically conductive material of the ball ring, such that the electrical circuitry is spaced from the inward-facing surface of the ball ring. The distance at which the electrical circuitry is spaced from the ball ring is a distance that extends beyond a normal degree of wear, or rather, the distance that generally corresponds to a degree of wear at which ball rings typically fail. Essentially, the distance between the inward-facing surface and the electrical circuitry is the distance at which wear of the ball ring becomes a safety concern.

[0013] The electrical circuit is connected to a sensor module, which is connected to the ball stud by an electrical conductor, wire, or cable. In use, the electrical circuit, the ball ring, the sensor module, the electrical conductor, the ball stud, and the ball head form a normally open circuit. During normal use of the ball joint, the layer of non-conductive material between the ball head and the electrical circuit of the ball ring wears down. If the ball head and the electrical circuit come into contact, or rather, if the ball ring is so worn that continued use could be dangerous, the open circuit closes, allowing energy to flow between the ball head and the electrical circuit.The sensor detects the closing of the previously open circuit and transmits a signal to an electronic control unit (ECU), which in turn activates at least one indicator device to notify the driver that the ball joint requires service. The indicator device can be a warning light that illuminates when ball joint service is necessary. Alternatively, the indicator device can be an audible signal that sounds periodically until the ball joint has been properly serviced.

[0014] In a standalone variation of the system for detecting overload, wear, and / or failure of a ball joint, the sensor module itself includes an indicator device, such as a switch, which is positioned within the sensor module during normal operation of the ball ring. However, when the sensor module is activated due to the closing of the electrical circuit, the switch is pushed out of or protrudes from the sensor module, thus providing a visual signal of ball joint failure. It is understood that the sensor module may include a different type of indicator device, such as a light source, instead of the switch.

[0015] According to yet another variation of the inventive system for detecting wear and / or failure of a ball joint, the ball ring comprises a rim with inwardly directed teeth. The rim is made of a material that squeaks / whistles when the teeth of the rim contact and rub against the steel outer surface of the ball head as the ball head moves within the ball housing relative to the ball ring. The teeth are dimensioned such that they are spaced apart from the inwardly facing surface of the ball ring.

[0016] In a further variation of the system for detecting overload, wear, and / or failure of a ball joint, sensors that can be used in other drive systems of the vehicle can be used to detect and identify high-load conditions at the ball joint and / or misuse of the ball joint. When a high-load condition of the ball joint is detected in the manner described above, the sensors transmit signals to the electronic control unit, which in turn transmits activation signals to at least one indicator device to inform the driver that the ball joint is under a high-load condition.

[0017] In a further variation of the inventive system for detecting overload, wear, and / or failure of a ball joint, the electrical circuit on the ball ring can be positioned such that the ingress of moisture into the ball joint or the presence of moisture in the grease can be detected by a change in the resistance of the electrical circuit. The ingress of moisture into the ball joint can also be detected by a moisture or water sensor, which can be positioned within the ball joint.

[0018] It is understood that the ball ring is generally the weakest structural component of a typical ball joint, and thus the load / force required to activate a sensor and transmit signals to the at least one display device could be tailored to the specific requirements of the vehicle, for example, based on specific control arm buckling / bending conditions. It is also possible that, in a variation of the inventive ball joint, the sensor could be integrated into other vehicle control systems in which an emergency running mode is activated upon detection of ball joint failure. The emergency running mode could include a special mode of operation of the vehicle's transmission and / or engine by the electronic control unit to ensure safe, limited drivability.

[0019] A further object of the present invention is to provide a system and a method for detecting overload, wear, and / or failure of a ball joint. The system comprises a ball housing in which a ball head of the ball joint is held. A ball ring is received in the ball housing and receives the ball head of the ball joint. An inwardly facing surface of the ball ring engages with the ball head in such a way that the ball head can pivot relative to the ball housing. A detection component is supported by the ball ring and is spaced at a set distance from an outer surface of the ball head. The detection component outputs an indicator signal to alert a driver when it detects a worn and / or failed condition of the ball joint. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings, which are integrated into and form part of the patent specification, depict various embodiments of the invention and, together with the general description of the invention provided above and the detailed description of the drawings provided below, serve to explain the principles of the invention. The invention will now be described by way of example with reference to the accompanying drawings, in which the following are shown: Fig. 1 a cross-sectional view of a ball joint with a system for detecting overload, wear and / or failure of a ball joint; Fig. 2 a view of a ball ring of a ball joint, which the system according to Fig. 1 includes; Fig. 3 a view of a ball ring of a ball joint comprising a variation of the system according to the invention; Fig. 4 a cross-sectional view of a ball ring comprising a variation of the system for detecting overload, wear and / or failure of a ball joint; Fig. 5 a schematic diagram of an electrical circuit of the system according to Fig. 4; Fig. 6 a perspective view of a standard ball ring; Fig. 7 a perspective view of a spherical ring that incorporates an electrical circuit of the system according to Fig. 4 includes; Fig. 8 a sectional view of a section of a ball ring of the system according to the invention; Fig. 9 a view of a ball ring that forms an electrical circuit of the system according to Fig. 4 includes, from the top; Fig. 10 a top view of a spherical ring that incorporates an electrical circuit of the system according to Fig. 4 includes; Fig. 11 Another top view of a spherical ring that incorporates an electrical circuit of the system according to Fig. 4 includes; Fig. 12 a schematic view of a ball joint with a system for detecting wear and / or failure of a ball joint; Fig. 13 a schematic view of a ball joint with a system for detecting wear and / or failure of a ball joint; Fig. 14 a schematic view of the system according to Fig. 13; Fig. 15 a schematic view of a variation of the system according to Fig. 13; Fig. 16 a schematic view of a ball joint with a system for detecting wear and / or failure of a ball joint; Fig. 17 a schematic view of a wreath of the system according to Fig. 16; Fig. 18 a schematic view of a ball joint with a system for detecting wear and / or failure of a ball joint; Fig. 19 a schematic view of a wreath of the system according to Fig. 18; and Fig. 20 a schematic view of the ball joint with the system according to Fig. 18, showing a ball ring in a worn state.

[0021] It is understood that the drawings are not necessarily to scale and that the disclosed embodiments are sometimes shown schematically and in partial views. In certain cases, details that are not necessary for understanding the present disclosure or that make other details difficult to discern may have been omitted. It is understood, of course, that the present disclosure is not limited to the specific embodiments shown herein. DETAILED DESCRIPTION OF PREFERRED EXECUTION FORMS

[0022] The present invention will be understood by reference to the following detailed description and in conjunction with the accompanying drawings. It is understood that the following detailed description of various embodiments is merely exemplary and is in no way intended to limit the scope of protection of the present invention.

[0023] With reference to the following Fig. Section 1 briefly describes the various components of a system for detecting wear and / or failure of a ball joint. The ball joint comprises a joint housing 2, which is open at both an upper end 4 and a lower end 6, and an inner surface 8 that defines a channel 10 along a longitudinal axis 12. The inner surface 8 of the joint housing 2 has an upper section 14, which is generally cylindrical. A lower section 16 of the inner surface 8 of the joint housing 2 is inclined radially inward from the upper section 14 of the inner surface 8 to the lower end 6 of the joint housing 2 such that the opening 16 at the lower end 6 of the joint housing 2 has a diameter that is less than the diameter of the opening 18 at the upper end 4 of the joint housing 2.A ball ring 20 is received in the channel 10 of the joint housing 2 and has an outer surface 22 with a profile that matches and / or fits with the inner surface 8 of the joint housing 2. An inwardly facing surface 24 of the ball ring 20 has a contour that is generally spherical and is thus able to fit closely with the spherical ball head 26 of a ball stud 28 when the ball joint is in an assembled state.

[0024] The ball head 26 can be made of steel or another resistant metal; preferably, the ball head 26 is made of an electrically conductive metal. The ball stud 28 extends axially from the ball head 26 through the opening 16 at the lower end 6 of the joint housing 2. The ball stud 28 can be integral with the ball head 26, or alternatively, the ball stud can be a separate component to which the ball head is rigidly fixed. For example, the ball head can have a threaded blind hole for a threaded ball stud. The ball stud 28 is preferably made of an electrically conductive metal. In the assembled state of the ball joint, the ball head 26, and thus the ball stud 28, is supported in the channel 10 of the joint housing 2 by the ball ring 20 such that the ball stud 28 extends out through the opening 16 at the lower end 6 of the joint housing 2.The spherical, inwardly facing surface 24 of the ball ring 20 holds the ball head 26 in a fixed position along the longitudinal axis 12, which is defined by the channel 10 in the joint housing 2. This means that, in the assembled state, the ball head 26 and the ball stud 28 are generally axially fixed, or rather, prevented from moving along the longitudinal axis 10 with respect to the joint housing 2. However, due to the corresponding spherical, inwardly facing surface 24 of the ball ring 20, the ball head 26 and the ball stud 28 are capable of rotating about an axis of rotation 30, which is defined by the ball stud 28, and are capable of pivoting about a center point 32 of the ball head 26 with respect to the joint housing 2.

[0025] A cover, or rather a cover plate 34, can be fitted into an annular groove in the joint housing 2 over the ball head 26 and the ball ring 20. The cover 34 can effectively hold the ball head 26 and the ball ring 20 in position within the joint housing 2. Alternatively, the joint housing 2 can be formed from a single piece, allowing the ball head 26 and the ball ring 20 to be fitted into one side of the housing before the joint is closed from the opposite side. In this alternative configuration, a cover 34 may not be necessary.

[0026] The ball joint can include a rubber sealing bellows 36. One end of the sealing bellows 36 is fixed to the lower end 6 of the joint housing 2, while the opposite end of the sealing bellows 36 is secured to the ball stud 28. The sealing bellows 36 forms a seal around the joint housing 2 and the ball stud 28, preventing the ingress of dirt, moisture, or other contaminants into the channel 10 through the lower end 6 of the joint housing 2. Dirt, moisture, and other contaminants are known to cause corrosion of the ball head 26 and increase the wear rate in the ball joint, thus reducing its performance and effective service life. The sealing bellows 36 is made of rubber or another flexible material that resists dirt, moisture, and other contaminants.

[0027] The ball joint can be used, for example, in a vehicle steering or suspension system, such as a wishbone linkage 38 (see Fig. 12, Fig. 13). During operation of the vehicle, that is, when the vehicle is driven along a road, the ball joint allows two components in the steering and suspension system to move relative to each other.

[0028] The ball ring 20 can comprise a body 40 that is slotted to facilitate its fit over the ball head 26 during installation / assembly. The body 40 can be in the form of sheets or sections 42, 42' that allow the ball ring 20 to spread open during installation / assembly and then close again after installation is complete. The body 40 of the ball ring 20 is made of a semi-rigid or elastic material, such as acetal or polyoxymethylene (POM). Although a number of materials can be used for the ball ring 20, it is advantageous in the present invention that the ball ring 20 is made of a non-electrically conductive material. Lubricants, such as grease, graphite, or oil, can be used to lubricate the interface between the ball head 26 and the ball ring 20.

[0029] According to a first variation of the inventive system for detecting wear and / or failure of a ball joint, a structure 44 is positioned within the ball ring 20, meaning that the structure 44 is enclosed within the body 40 of the ball ring 20, for example, by a forming or fitting process. The structure 44 comprises a number of ribs or forks 46 that extend within the ball ring 20 such that they substantially surround the ball head 26 in the area where failure would be most readily detected. The ribs or forks 46 are formed from a material different from that of the body 40 of the ball ring 20. In this variation of the system for detecting wear and / or failure of a ball joint, the structure 44 can either be partially or completely positioned in the body 40 of the ball ring 20 or can be supported on the outer surface 22 of the ball ring 20.According to the invention, the material from which the structure 44 is formed is generally harder or more resistant than the material from which the body 40 of the ball ring 20 is formed. Due to the difference in hardness / resistance between the material of the body 40 and the material of the structure 44, if sufficient force is exerted on the ball joint, for example, if the vehicle encounters a pothole, a curb, or another obstacle, or if the vehicle travels at high speed along an uneven road, the ball ring 20 can be deformed or otherwise damaged. The deformation of the structure 44 of the ball ring 20 causes an uneven distribution of contact between the inwardly facing surface 24 of the ball ring 20 and the outer surface 48 of the ball head 26 while the ball stud 28 rotates, pivots, or moves within the ball ring 20 relative to the joint housing 2.The uneven distribution of contact between the ball head 26 and the deformed ball ring 20 results in audible noises that can be perceived by the vehicle driver. Since the structure 44 is positioned within the body 40 of the ball ring 20 at a distance from its inwardly facing surface 24, the structure 44 will eventually, with sufficient wear of the body 40's material, contact the outer surface 48 of the ball head 26. The distance between the structure 44 and the inwardly facing surface 24 of the ball ring 26 is described in more detail below with reference to an alternative to the structure 44. The contact between the structure 44 and the ball head 26 also results in audible noises that can be perceived by the vehicle driver. Continued driving of the vehicle can cause these noises to become louder.These noises inform or notify the driver of the motor vehicle that the ball ring 20, i.e., the ball joint, has failed and simultaneously signal that maintenance of the motor vehicle is required. Although the ball ring 20 may be deformed and thus reduce the operation of the ball joint, it is understood that the ball joint may continue to function for a certain period of time, particularly if the ball ring 20 holds the ball head 26 in position within the ball housing 2.

[0030] The structure 44 of ribs or forks 46 can be arranged in such a way that it corresponds to the construction of the body 40 of the spherical ring 20, however it is understood that the structure 44 extends at least partially around a circumference of the spherical head 26. Fig. Figure 1 shows a cross-sectional view of a ball joint comprising a structure 44 of ribs 46, which are generally oriented horizontally in the ball ring 20 around the ball head 26. The horizontal arrangement of the ribs 46 is formed by Fig. 2, in which the ribs 46 are shown as dashed lines arranged to be perpendicular to the longitudinal axis 12 of the spherical housing 2. Fig. Figure 3 shows a variation in which the ribs 46 are arranged vertically in the body 40 of the ball ring 20. It is understood that the ribs 46 can be connected to one another and arranged in any orientation relative to each other; for example, the ribs 46 can cross each other. However, it is important that the ribs 46 extend around a large part of the periphery of the ball head 26. It is further explicitly noted that the ribs 46 can extend over a large part of the vertical height of the ball head 26.

[0031] With reference to the following Fig. A second variation of the present invention is described in Sections 4, 5, and 7-12. Since this embodiment is very similar to the embodiment discussed previously, only the differences between this new embodiment and the previous embodiment are discussed in more detail, with identical elements being designated with identical reference numerals.

[0032] In the second variation of the inventive system for detecting wear and / or failure of a ball joint, the ball head 26 is preferably made of an electrically conductive metal, such as steel. The body 40 of the ball ring 20, in turn, is made of a semi-rigid elastic material that is not electrically conductive. As shown in the figures, the body 40 of the ball ring 20 comprises an electrical circuit 50 that is encapsulated in the non-conductive material of the body 40 of the ball ring 20, for example, by a forming process. The electrical circuit 50 can be formed, for example, by a printed circuit or electrical conductors that extend through the body 40 as ribs or forks 52. A two-dimensional design of the electrical circuit 50 is shown in Fig. Figure 5 shows that to encapsulate the electrical circuit 50 in the body 40 of the spherical ring 20, the electrical circuit 50 can be applied to an inner surface of a preform of the spherical ring 20, i.e., printed or glued onto it. After fixing the electrical circuit 50 to the preform body of the spherical ring 20, the spherical ring 20 can then be formed, for example, with a non-electrically conductive material.

[0033] The ribs or forks 52 of the electrical circuit 50 can form the design according to the illustration in Fig. 5 or the ribs or forks 52 of the electrical circuit 50 may generally extend in the body of the ball ring 20 in any configuration, as long as the ribs or forks 52 extend around the periphery of the ball head 26 and along the vertical height of the ball head 26 to cover the main area associated with wear and safety of the ball joint. Fig. 6 represents a standard ball ring, whereas the one in Fig. The spherical ring 20 shown in Figure 7 comprises an electrical circuit 50 that generally extends around the periphery of each of the leaves or regions 42, 42' of the body 40 of the spherical ring 20. The design of the electrical circuit 50 in the spherical ring 20 will Fig. 9-11 shown schematically. The respective electrical circuits of the leaves or sections 42, 42' are connected via a bridge element 54 as shown in the illustration in Fig. 11 interconnected.

[0034] Due to the forming process, the electrical circuit 50 is positioned in the body of the spherical ring 20 at a distance 56 from its inwardly facing surface 24. The electrical circuit 50 is also spaced away from the electrically conductive outer surface 48 of the spherical head 26. In particular, the electrical circuit 50 should be spaced away from the inwardly facing surface 24 of the spherical ring 20 so that, when the electrically conductive spherical head 26 is inserted into the spherical ring 20, no electrical energy can flow between the spherical head 26 and the electrical circuit 50 in the spherical ring 20. How best to achieve this is described in the following sections. Fig. As shown in Figure 8, the electrical circuit 50 is arranged such that it is located closer to the inward-facing surface 24 of the spherical ring 20 than to the outer surface 22 of the spherical ring 20. The leaves or regions 42, 42' of the spherical ring 20 generally have a thickness 58 in the range of 1.0 mm to 2.0 mm; for example, the thickness 58 of the leaves or regions 42, 42' of the spherical ring 20 may be 1.5 mm. The electrical circuit 50 is spaced from the inward-facing surface 24 of the spherical ring 20 at a distance 56 of approximately between 0.2 mm and 0.8 mm; for example, the electrical circuit is spaced at a distance 56 of approximately 0.5 mm from the inward-facing surface 24 of the spherical ring 20.The distance 56, at which the electrical circuit 50 is spaced from the inwardly facing surface 24 of the ball ring 20, is at least approximately a distance that represents a normal degree of wear, or rather, that generally corresponds to the degree of wear at which a ball ring typically fails. Essentially, the distance 56 between the inwardly facing surface 24 of the ball ring 20 and the electrical circuit 50 is the distance at which the wear of the ball ring 20 becomes a safety issue.

[0035] The ball ring 20 has a connection point 60, which is generally positioned centrally along the bridge member 54 between the leaves or sections 42, 42', at which the electrical circuit 50 is exposed and can be coupled to a sensor module 64 via an electrical connector 62. The sensor module 64 is in turn connected to an electrical control unit 66 by an electrical line, wire, or cable 68. The sensor module 66 can also be connected to the ball stud 28 by another electrical line, wire, or cable 70.

[0036] Since the electrical circuit 50 is encapsulated in the non-conductive material of the ball ring 20 at a distance from the ball head 26, the electrical circuit 50 is normally open. This means that, due to the layer 70 of non-conductive material molded onto the body 40 of the ball ring 20, no electrical energy is transferred between the ball head 26 and the electrical circuit 50 within the ball ring 20. Over the service life of the ball joint, the layer 70 of non-conductive material of the ball ring 20 between the ball head 26 and the electrical circuit 50 wears down. When the ball head 26 and the electrical circuit 50 come close enough to each other or touch, electrical energy can flow between the ball head 26 and the electrical circuit 50 within the ball ring 20. The sensor module 64 detects the flow of electrical energy when the previously open circuit closes.When the circuit closes, the sensor module 64 transmits a sensor signal to the electronic control unit 66, which in turn transmits an activation signal to at least one indicator device 72 to notify the driver that the ball joint requires maintenance. The indicator device 72 can be a warning light that illuminates or an audible indicator device that emits an audible tone to inform the driver that maintenance of the ball joint is required.

[0037] In an independent variation of the system for detecting wear and / or failure of a ball joint as shown in Fig. 13-15 The ball joint can comprise a self-contained system in which a sensor module 74 itself includes a display device 76. The sensor module 74 can include a clip 77 that is coupled to the control arm linkage 38. An electrical wire or conductor 75 is coupled to the ball stud 28 by another clip 77'. The module 74 has a display device switch 76 that is retracted into the sensor module 74 in the normal state of the ball ring 20 ( Fig. 13), however, when the sensor module 74 is activated by detecting the flow of electrical energy, the switch 76 is pushed out of the sensor module 74 and / or protrudes from it ( Fig. 14). It is understood that the sensor module 74 may include a different type of indicator device 76 instead of a switch, such as a light source that illuminates when activated. In a further variation of the in Fig. In the system shown in Figure 15, the sensor device 74 can include a transmitter 81 which wirelessly sends an activation signal to a receiver 83 which is connected to a display device 72.

[0038] In a further variation of the inventive system for detecting wear and / or failure of a ball joint, the electrical circuit 50 can be arranged on the ball ring 20 at such a location that the ingress of moisture into the ball joint or the presence of moisture in the ball joint lubricant can be detected by a change in the resistance of the electrical circuit 50. For example, the electrical circuit 50 can extend to the lower end of the ball ring 20 so that it is exposed to an open inner region 78 in the sealing bellows 36 ( Fig. 4) The ingress of moisture into the ball joint can also be detected by a moisture or water sensor, which can be positioned in the ball joint. In this case, it is preferred to lubricate and protect the ball joint using a conductive grease.

[0039] According to yet another variation of the inventive system for detecting wear and / or failure of a ball joint, a ring 80, as in Fig. 16 and Fig. As shown in Figure 17, the ring 80 is positioned within the ball ring 20 and is arranged along a lower section 82 of the ball ring 20, radially surrounding a lower section 84 of the ball head 26. The ring 80 is made of a material different from the material of the body 40 of the ball ring 20. Preferably, the ring 80 is made of a material that squeaks / whistles or otherwise produces noise when the ring 80 contacts and rubs against the steel outer surface 48 of the ball head 26 as the ball head 26 moves within the ball housing 2 relative to the ball ring 20. Preferably, the ring 80 is made, for example, of a ceramic, plastic, or rubber material. In this variation, the ring 80 is embedded in an annular groove or an annular passage in the outer surface 22 of the ball ring 20. The ring 80 comprises a number of teeth 86 which extend radially inwards towards the ball head 26.The teeth 86 have inwardly directed flanks 88 and are dimensioned such that the flanks 88 of the teeth 86 are spaced at a distance from the inwardly directed surface 24 of the ball ring 20 and thus from the outer surface 48 of the ball head 26 when the ring 80 is joined with the ball ring 20.

[0040] The wreath can also be made from a thin metal ring (90°). Thin metal rings (90°) can be stamped from sheet metal and pressed to achieve the desired contour in a particularly simple way. Fig. Figures 18-20 represent a ball ring 20 with a thin metal rim 90. Similar to the rim described above, the thin metal rim 90 has a number of teeth 92 extending radially inwards towards the ball head 26. The teeth 92 have inner surfaces 94 spaced apart from the inwardly facing surface 24 of the ball ring 20 and thus from the outer surface 48 of the ball head 26 when the thin metal rim 90 is joined to the ball ring 20. As the ball ring 20 wears down and the quality of the grease deteriorates, the thin metal rim 90 comes into contact with the outer surface 48 of the ball head 26. In this condition, if the ball head 20 oscillates, for example due to bumps in the road, it vibrates, as indicated by arrows 96 in Figure 18-20. Fig. As shown in Figure 20, the thin metal ring 90 contacts the ball head 26 and / or the ball housing 2, producing audible noises. It is understood that the toothed rings 80, 90 discussed above are merely examples, as rings can also be formed with a variety of other shapes and / or contact patterns. The ball rings 20, which are shown in Fig. 16 and Fig. Figure 18 is shown to be in good working order, meaning that the rings 80 and 90 are spaced apart from the inwardly facing surface 24 of the spherical ring 20. In contrast, Fig. Figure 20 shows a ball ring 20 in a worn condition, which must be replaced for the proper functioning of the ball joint. In this figure, the teeth 92 of the ring 90 contact the outer surface 48 of the ball head 26. Fig. The inward-facing surface 24 of the spherical ring 20 is represented as a dashed line 98 when the spherical ring 20 is in a new, unused state. When the spherical ring 20 is in a new state, as in Fig.As shown in Figure 8, the teeth 88, 92 of the rings 80, 90 are spaced at a distance 56, which is approximately between 0.2 mm and 0.8 mm, from the inwardly facing surface 24 of the ball ring 20. For example, the teeth 88, 92 are spaced at a distance 56 of approximately 0.5 mm from the inwardly facing surface 24 of the ball ring 20. This distance 56 is at least approximately a distance that represents a normal degree of wear, or rather, that generally corresponds to the degree of wear at which a ball ring usually needs to be replaced. The noise caused by the contact between the teeth of the rings and the outer surface of the ball head informs or notifies the driver of the motor vehicle that the ball joint requires maintenance, i.e., that the ball ring needs to be replaced.

[0041] In a further variation of the inventive system for detecting wear and / or failure of a ball joint, sensors that can be used in other drive systems, e.g., the transmission control system, of the motor vehicle can be used to detect and identify high-load conditions at the ball joint and / or misuse of the ball joint. When a high-load condition of the ball joint is detected in the manner described above, the sensors transmit signals to the electronic control unit, which in turn transmits activation signals to at least one display device to inform the driver that the ball joint is under a high-load condition.

[0042] According to a method for detecting overload, wear, and / or failure of a ball joint, these conditions are detected by the following steps. First, a ball joint with a ball ring is provided with a detection component as described above. After installation, the ball joint is allowed to function as intended. During use, the inward-facing surface of the ball ring is allowed to wear down, reducing the gap between a detection component of the system within the ball ring and the outer surface of the ball head. The detection component is then allowed to contact the outer surface of the ball head when the ball ring is sufficiently worn. The system according to the invention then outputs an indicator signal that is detectable by the driver of the vehicle.The system is designed and dimensioned in such a way that the output of the display signal indicates that the ball joint requires maintenance.

[0043] Although various embodiments of the present invention have been described in detail, it is obvious that a person skilled in the art would conceive of and readily recognize various modifications and alterations to those embodiments. It is expressly understood, however, that such modifications and alterations are within the scope and concept of the present invention as set forth in the pending claims. Furthermore, other embodiments of the invention are possible, and it can be implemented or carried out in practice in various other similar ways. Moreover, it is understood that the language and terminology used here serve the purpose of description and are not to be construed as limitations.The use of "comprehensive" or "exhibiting" and variations thereof here is intended to include the objects listed therein and their equivalents as well as additional objects, whereas only the terms "consisting of" and "merely consisting of" are to be interpreted as limitations.

Claims

[1] System for detecting possible failure and / or sufficient wear of a ball joint, the system comprising: a ball housing (2); a ball ring (20) received in the ball housing (2); a ball head (26) integrally fixed to one end of a ball stud (28); wherein the ball head (26) of the ball stud (28) is received and held in the ball housing (2), the ball ring (20) separating the ball head (26) from the ball housing (2), and an inwardly facing surface (24) of the ball ring (20) engaging with the ball head (26) so that the ball head (26) is movable with respect to the ball housing (2); a detection component supported by the ball ring (20) such that the detection component is initially spaced at a desired distance from the inwardly facing surface (24) of the ball ring;and wherein, in the event of either failure or sufficient wear of the ball ring (20), the detection component engages with an outer surface (48) of the ball head (26) and generates an indicator signal that alerts a driver, indicating that maintenance of the ball joint is required; characterized by , that the detection component has a structure (44) with multiple ribs and / or an electrical circuit with multiple forks (46), wherein the multiple ribs and / or forks (46) are housed in the spherical ring (20) and substantially surround a periphery of the spherical head (26). [2] System according to claim 1, wherein the detection component is at least one metallic component which, in the event of either failure or sufficient wear of the ball ring, rubs against the outer surface of the ball head to generate the indicator signal which alerts the driver that maintenance of the ball joint is required. [3] System according to claim 2, wherein the ball ring is made of a different material than the metal component from which the detection component is formed, and the material from which the ball ring is formed is less resistant than the metal from which the detection component is formed. [4] System according to one of the preceding claims, wherein each of the multiple ribs is spaced apart from the inwardly facing surface of the spherical ring in an initial installed state. [5] System according to one of the preceding claims, wherein the detection component comprises a structure having several ribs, each of which in an initial installed state of the ball ring is supported at a distance of between 0.2 mm and 0.8 mm from the inwardly facing surface of the ball ring, and the structure substantially surrounds a periphery of the ball head. [6] System according to any of the preceding claims, wherein the detection component generates an audible and / or a tactile indicator signal when the detection component rubs against the outer surface of the ball joint, thereby alerting and indicating to the driver that maintenance of the ball joint is required. [7] System according to one of the preceding claims, wherein the detection component comprises an annular ring which is supported by the ball ring and spaced apart from the inwardly facing surface of the ball ring, wherein the annular ring surrounds a periphery of the ball head and the annular ring is arranged next to an end of the ball ring which has an opening through which the ball stud extends. [8] System according to claim 7, wherein an outer surface of the spherical ring has a passage which receives the annular rim such that inwardly facing surfaces of the annular rim are spaced between 0.2 mm and 0.8 mm apart from the inwardly facing surface of the spherical ring in an initial installed state of the spherical ring. [9] System according to claim 7, wherein the annular ring generates an audible and / or tactile indicator signal that identifies when the annular ring is rubbing against the outer surface of the ball head, thereby alerting the driver and indicating that maintenance of the ball joint is required. [10] System according to one of the preceding claims, wherein the ball ring is made of a non-electrically conductive material, wherein the electrical circuit is housed in the ball ring and substantially surrounds a periphery of the ball head, wherein the electrical circuit is spaced apart from the inwardly facing surface of the ball ring in an initial installed state of the ball ring, and the electrical circuit is connected to a sensor module that detects electrical variations in the electrical circuit. [11] System according to one of the preceding claims, wherein each of the multiple forks in an initial installed state of the ball ring is spaced between 0.2 mm and 0.8 mm from the inwardly facing surface of the ball ring, and the contact between the electrical circuit and the outer surface of the ball head, in the event of either failure or sufficient wear of the ball joint, causes the electrical variations in the electrical circuit and the sensor module generates the display signal upon detection of the electrical variations. [12] System according to one of the preceding claims, wherein the detection component comprises the sensor module and a display device that communicate with each other, such that upon detection of electrical variations in the electrical circuit, the sensor module activates the display device which outputs an optical display signal and / or an audible display signal to alert the driver that maintenance of the ball joint is required. [13] System according to one of the preceding claims, wherein the detection component comprises an electrical connection that enables the sensor module to be coupled to the electrical circuit, the sensor module has an electrical conductor that is connected to the ball stud, the ball stud and the ball head are made of an electrically conductive material so that electrical energy can be transferred from the sensor module to the ball head and the electrical circuit, and the sensor module detects a flow of electrical energy between the electrical circuit and the ball head in a worn condition of the ball ring when the electrical circuit directly touches the outer surface of the ball head, the sensor module is connected to an electrical control unit that is connected to at least one display device so that when the sensor module detects that maintenance of the ball joint is required,The sensor module transmits a sensor signal to the electronic control unit, which activates at least one display device to output the display signal. [14] System according to claim 13, wherein the at least one indicator device is a light source and / or an audible indicator device that lights up or produces an audible tone when maintenance of the ball joint is detected by the sensor module. [15] System according to claim 2, wherein a lower end of the ball ring has a first opening and a lower end of the ball housing has a second opening, the ball ring is received in the ball housing such that the first and the second opening are coaxially aligned with each other, the ball head is received in the ball ring such that the ball stud extends through both the first and the second opening, a sealing bellows is connected to the ball housing and the ball stud in such a way as to enclose the lower ends of the ball ring and the ball housing, and the electrical circuit is supported in the ball ring such that one end of the electrical circuit is open to an inwardly facing side of the sealing bellows, the end of the electrical circuit is a humidity sensor,so that any ingress of moisture within the inward-facing side of the sealing bellows is detectable by the moisture sensor and the moisture sensor generates a detection signal to alert the driver that moisture is present in the ball joint. [16] System according to one of the preceding claims, wherein the sensor module comprises a transmitter which can be activated when the sensor module detects electrical variations in the electrical circuit, the transmitter wirelessly transmits an activation signal via a receiver to a display device which, when activated, outputs display signals when the sensor module detects the electrical variations in the electrical circuit.

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