Method and apparatus for limiting loads applied to a rotatable coupling

Abstract

The present invention discloses a method, apparatus and article for limiting a load applied to a rotatable coupling. An exemplary apparatus includes: a comparator, which determines whether at least one of the angle of the rotatable coupling or the torque applied to the coupling exceeds a threshold value based on at least one of the torque or the angle; and a limiter, which is used to limit at least one of the angle or the torque when at least one of the torque or the angle exceeds the threshold value.

Description

Technical Field

[0001] The present disclosure relates generally to vehicles and, more particularly, to a controller for limiting loads applied to a rotatable coupling. Background Art

[0002] The vehicle powertrain may implement a rotatable coupling such as a constant velocity (CV) universal joint to transfer torque provided by an engine and / or other mechanical power source of the vehicle to one or more steered wheel assemblies. In addition, the rotatable coupling may be used to change the torque orientation from the orientation of the mechanical power source coupled or otherwise connected to the vehicle to the orientation of the steered wheels included in one or more steered wheel assemblies of the vehicle.

[0003] Additionally, the maximum torque that can be transmitted through the rotatable coupling before failure (e.g., cracking, breaking, loss of integrity, etc.) varies with the operating angle of the rotatable coupling (e.g., the magnitude of the change in torque orientation). For a rotatable coupling in a vehicle driveline, the operating angle of the rotatable coupling varies with the magnitude of the steering angle of the vehicle and the position of the suspension. Therefore, applying a large torque to the rotatable coupling of a vehicle driveline at large steering angles and / or a large amount of suspension travel (e.g., when drifting, driving on a loop, driving off-road, etc.) may, in some cases, cause the rotatable coupling to fail. Summary of the invention

[0004] A device for limiting a load applied to a rotatable coupling is disclosed herein. An exemplary device includes: a comparator, which determines whether at least one of the angle of the rotatable coupling or the torque applied to the coupling exceeds a threshold value based on at least one of the torque or the angle; and a limiter, which is used to limit at least one of the angle or the torque when at least one of the torque or the angle exceeds the threshold value.

[0005] Another exemplary apparatus includes a constant velocity (CV) joint load controller for evaluating at least one of a torque applied to a CV joint or an angle of the CV joint, and wherein the controller is for limiting at least one of a torque applied to the CV joint or an angle of the CV joint when at least one of the torque applied to the CV joint or the angle of the CV joint exceeds a threshold.

[0006] An exemplary method includes: measuring at least one of an angle of a rotatable coupling or a torque applied to the coupling; determining whether at least one of the torque applied to the coupling or the angle of the coupling exceeds a threshold; and limiting at least one of the angle of the coupling or the torque applied to the coupling in response to at least one of the torque applied to the coupling or the angle of the coupling exceeding the threshold. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 An exemplary vehicle including a CV joint assembly and a CV load controller by which the examples disclosed herein may be implemented is shown.

[0008] Figure 2A Shown in more detail Figure 1 CV universal joint assembly.

[0009] Figure 2B Shows Figure 2A An internal view of a portion of a CV joint assembly.

[0010] Figure 3 is further elaborated Figure 1 Block diagram of a CV joint load controller by which the examples disclosed herein may be implemented.

[0011] Figure 4 It means that it can be executed to implement Figure 3 A flow chart of an exemplary method of an exemplary CV joint load controller.

[0012] Figure 5 It means that it can be executed to implement Figure 3 A flow chart of an exemplary method of an exemplary torque limiter.

[0013] Figure 6 It means that it can be executed to implement Figure 3 Flowchart of an exemplary method of an exemplary angle limiter.

[0014] Figure 7 is able to execute instructions to perform Figure 4 , Figure 5 and / or Figure 6 Methods to implement Figure 1 A block diagram of an exemplary processing platform of an exemplary system.

[0015] The drawings are not drawn to scale. Whenever possible, the same reference numerals will be used to refer to the same parts throughout the drawings and accompanying written description. As used in this patent, stating that any part (e.g., a layer, film, region, or plate) is positioned on another part in any manner (e.g., positioned on, located on, disposed on, or formed on, etc.) indicates that the referenced part is in contact with the other part, or that the referenced part is above the other part with one or more intermediate parts located therebetween. Stating that any part is in contact with another part means that there are no intermediate parts between the two parts. DETAILED DESCRIPTION

[0016] The vehicle drivetrain may implement a rotatable coupling (e.g., a CV joint) capable of transmitting torque to the steered wheels, wherein the orientation of the torque output at the steered wheels may be different from the orientation of the torque input at a drive shaft coupled or otherwise connected to the vehicle's mechanical power source (e.g., the drivetrain). Typically, the operating angle of a rotatable coupling (such as a CV joint) increases with an increase in the steering angle commanded by a vehicle user and / or an increase in the travel of the vehicle's suspension system.

[0017] In some cases, the maximum torque that a CV joint can transmit without failure decreases as the operating angle of the joint increases. Transmitting large torques applied to the CV joint during periods of large steering angles and / or large amounts of suspension travel (e.g., when drifting, driving on a loop, driving off-road, etc.) may, in some cases, cause the CV joint to fail (e.g., crack, break, reduced integrity, etc.). Similarly, commanding large steering angles or inducing large amounts of suspension travel during periods of large torque transmission may also, in some cases, cause the CV joint to fail.

[0018] CV joints are typically designed through size and material selection to be able to transmit the maximum torque output by the vehicle's powertrain at the vehicle's maximum steering angle and / or maximum suspension travel. However, for some vehicles, the CV joints may not be designed to the above standards due to space constraints, material constraints, etc. In such cases, the CV joints may be damaged by transmitting the maximum torque output by the powertrain at the maximum steering angle and / or maximum suspension travel. Such damage to the CV joint may prevent operation of the vehicle, strand the user of the vehicle, and / or require replacement of the CV joint.

[0019] Examples disclosed herein limit at least one of the torque transmitted by (e.g., applied to) a rotatable coupling (such as a CV universal joint) and the operating angle of the coupling. More specifically, these examples limit at least one of the transmitted torque and the operating angle to prevent the rotatable coupling from failing during vehicle operation. Although the examples described below are described as being applied to a vehicle having a CV universal joint, the teachings of the present disclosure may be more generally applied to other rotatable couplings, such as universal joints, flexible couplings, and the like.

[0020] As will be described in more detail below, the examples described herein provide a CV joint load controller to evaluate the torque transmitted by the CV joint and the operating angle of the CV joint, and limit at least one of the applied torque and the operating angle in response to at least one of the applied torque and the operating angle exceeding a threshold.

[0021] In some examples, when the torque transmitted to the steered wheels is limited, the CV joint load controller disclosed herein reallocates a portion of the torque (e.g., additional torque) commanded by a user of the vehicle to the non-steered wheels, such that the total output torque of the vehicle matches the commanded torque even when the torque of the steered wheels is limited. Additionally or alternatively, a portion of the torque commanded by the user of the vehicle may be reallocated to a smaller steering wheel of one or more steered wheels, the angle of the smaller steering wheel being based on Ackerman steering geometry.

[0022] As will be discussed in more detail below in accordance with the teachings of the present disclosure, the CV joint load controller can have various configurations that can depend on the type of CV joint and / or characteristics associated with the vehicle to which the CV joint load controller is applied. In the examples disclosed herein, when at least one of the torque transmitted through the CV joint and the operating angle of the CV joint is limited, the configurations can be modified or changed to optimize at least one of the limitation of the load applied to the CV joint and / or the user experience.

[0023] With reference to the accompanying drawings, Figure 1 An exemplary vehicle 100 implementing the teachings of the present disclosure is shown. The vehicle 100 may include one or more steered wheels 102, one or more non-steered wheels 104, and one or more powertrains 106. Figure 1In the illustrated example of , the vehicle 100 has two steered wheels 102, two non-steered wheels 104, and a driveline 106. In addition, at least one of the one or more steered wheels 102 and the one or more non-steered wheels 104 is coupled to the driveline 106 via one or more CV joint assemblies 108. In such an example, the one or more CV joint assemblies 108 transfer torque output from the driveline 106 to at least one of the one or more steered wheels 102 and the one or more non-steered wheels 104. Figure 1 In the example of FIG. 1 , the vehicle 100 includes two CV joint assemblies 108 that couple two steerable wheels 102 to one driveline 106. Additionally, the torque output by the driveline 106 may be measured by a driveline controller 110 that determines the torque output using one or more sensors disposed in the driveline 106.

[0024] In some examples, the steering angle of the one or more steered wheels 102 may vary with input from a user of the vehicle 100. Additionally, the steering angle of the one or more steered wheels 102 may be controlled by an electronic power assisted steering (EPAS) system 112. In such examples, the EPAS system 112 controls the steering angle of the one or more steered wheels based on input from at least one of a user of the vehicle 100 or a computer system. In some examples, due to the geometry of the one or more steered wheels 102, a separate steering angle will be commanded to each steered wheel 102 based on Ackermann steering geometry. In some examples, the EPAS system 112 may also include a steering angle sensor 114 to determine the steering angle of the one or more steered wheels 102.

[0025] In addition, the vehicle 100 may include one or more suspension systems 116 to provide a comfortable ride for the occupants of the vehicle 100. In some examples, the one or more steered wheels 102 and the one or more non-steered wheels 104 are coupled to the vehicle 100 via the one or more suspension systems 116. In addition, each of the one or more suspension systems 116 has a stiffness and a range of motion (e.g., suspension travel), and in some cases, each of the one or more suspension systems 116 functions independently of each other. In addition, in some examples, the position of the one or more suspension systems 116 measured by the one or more ride height sensors 118 affects the operating angle of the one or more CV joint assemblies 108.

[0026] In some examples, the vehicle 100 may be a front wheel drive (FWD) vehicle or a four wheel drive (4WD) vehicle. In FWD and 4WD vehicles, one or more steering wheels 102 are powered and receive torque from the drivetrain 106. In an example where the vehicle 100 is a 4WD vehicle, one or more steering wheels 102 and one or more non-steering wheels 104 are powered and receive torque from the drivetrain 106. Additionally, in an example where the vehicle 100 is a FWD vehicle, one or more non-steering wheels 104 are not powered and do not receive torque from the drivetrain 106.

[0027] Figure 1 The vehicle 100 shown in FIG. 1 also includes an exemplary constant velocity joint load controller 120, which is described below in conjunction with Figure 3 The constant velocity (CV) joint load controller 120 receives at least one of the torque applied to the CV joint assembly 108 by the powertrain 106 and the operating angle of the CV joint assembly 108. The operating angle may be based on the steering angle received from the EPAS system 112 and the suspension position received from the suspension system 116. If the CV joint load controller 120 determines that the torque and / or the operating angle exceed a predefined threshold, the CV joint load controller 120 limits at least one of the torque applied to the CV joint assembly 108 and the operating angle of the CV joint assembly 108 to prevent the CV joint assembly 108 from malfunctioning.

[0028] Figure 2A Shown in more detail Figure 1 CV universal joint assembly 108. Figure 2A The CV joint assembly 108 has a first end 202 and a second end 204. In some such examples, the first end 202 is coupled to the drivetrain 106 and the second end is coupled to the steered wheel 102. In addition, the first end 202 remains coaxial with the output of the drivetrain 106 and the second end 204 remains coaxial with the input of the steered wheel 102. In addition, the CV joint assembly 108 includes a first CV joint 206 and a second CV joint 208. In some examples, such as Figure 2A In the illustrated example, the first CV universal joint 206 couples the first end 202 to the shaft 210. In addition, the first CV universal joint 206 can allow the axis of the first end 202 and the axis of the shaft 210 to extend at different angles and can transfer torque from the first end 202 to the shaft 210, wherein the orientation of the torque at the first end 202 can be different from the orientation of the torque at the shaft 210.

[0029] In addition, the second CV joint 208 couples the second end 204 to the shaft 210. Furthermore, the second CV joint 208 may allow the axis of the second end 204 and the axis of the shaft 210 to extend at different angles and may transfer torque from the shaft 210 to the second end 204, wherein the orientation of the torque at the shaft 210 may be different from the orientation of the torque at the second end 204. In operation, the torque output by the powertrain 106 is transferred to the first end 202, which transfers the torque to the shaft 210 through the first CV joint 206, which further transfers the torque to the second end 204 through the second CV joint 208, which further transfers the torque to the steered wheels 102.

[0030] Figure 2B Shows Figure 2A An internal view of a portion of the CV joint assembly 108. Figure 2B In the example shown, the second CV joint 208 is a Rzeppa type constant velocity joint.

[0031] Figure 3 is further elaborated Figure 1 1 is a block diagram of a CV joint load controller 120, by which examples disclosed herein may be implemented. In some examples, the example CV joint load controller 120 may include an example torque determiner 302, an example angle determiner 304, an example comparator 306, which in some examples may include an example threshold memory 308, an example torque comparator 310, and an example angle comparator 312. The CV joint load controller 120 also includes an example limiter 314, which in some examples may include an example angle limiter 316 and an example torque limiter 318, an example EPAS interface unit 320, and an example powertrain interface unit 322.

[0032] An exemplary torque determiner 302 included or otherwise implemented by the CV joint load controller 120 is capable of determining a torque applied to at least one of the first CV joint 206 and the second CV joint 208. Determining the applied torque may also include receiving a signal from the powertrain controller 110. In some examples, the received signal is an analog voltage. In such examples, the torque determiner 302 determines a torque value based on the received voltage value using a previously determined calibration curve of the signal output by the powertrain controller 110. Additionally or alternatively, the received signal may be a data packet including a digital representation of the torque value.

[0033] An exemplary angle determiner 304 included or otherwise implemented by the CV joint load controller 120 is capable of determining an operating angle of at least one of the first CV joint 206 and the second CV joint 208. Determining the operating angle may also include receiving a signal from at least one of the steering angle sensor 114 and the ride height sensor 118. In some examples, the received signal is an analog voltage. In such examples, the angle determiner 304 utilizes a known calibration curve for at least one of the steering angle sensor 114 and the ride height sensor 118 to determine at least one of the steering angle and the suspension position. Additionally or alternatively, the received signal is a digital data packet that includes data representing at least one of the steering angle and the suspension position.

[0034] In addition, the angle determiner 304 further determines the operating angles of the first CV joint 206 and the second CV joint 208 based on at least one of the steering angle and the suspension position. In some examples, when the vehicle 100 includes the steering angle sensor 114 and the ride height sensor 118, the angle determiner 304 determines the operating angles of the first CV joint 206 and the second CV joint 208 based on the steering angle and the suspension position. Additionally or alternatively, when the vehicle 100 includes only one of the steering angle sensor 114 or the ride height sensor 118, the angle determiner 304 determines the operating angles of the first CV joint 206 and the second CV joint 208, respectively, based on only one of the steering angle and the suspension position.

[0035] When each of the torque determiner 302 and the angle determiner 304 determines the torque applied to the first CV universal joint 206 and the second CV universal joint 208 and the operating angle of the first CV universal joint and the second CV universal joint, the applied torque and the operating angle are further transmitted to the example comparator 306. In some examples, the comparator 306 includes or otherwise implements the example threshold memory 308, the example torque comparator 310, and the example angle comparator 312. In such examples, the applied torque is transmitted to the torque comparator 310, and the operating angle is transmitted to the angle comparator 312.

[0036] like Figure 3 As shown, the threshold memory 308 can store at least one of a torque threshold and an operating angle threshold for at least one of the first CV universal joint 206 and the second CV universal joint 208. In some examples, the torque threshold and the operating angle threshold stored by the threshold memory 308 are fixed values ​​based on one or more characteristics of the first CV universal joint 206 and the second CV universal joint 208. In such examples, the one or more stored characteristics are further based on known failure criteria of the first CV universal joint 206 and the second CV universal joint 208.

[0037] Additionally or alternatively, one or more characteristics stored by the threshold memory 308 may be variable values ​​that vary with at least one of age and / or use of the first CV universal joint 206 and the second CV universal joint 208. In such examples, the variable values ​​are further based on known failure criteria for the first CV universal joint 206 and the second CV universal joint 208. Furthermore, the threshold memory 308 communicates the torque threshold to the torque comparator 310 and the operating angle threshold to the angle comparator 312.

[0038] Additionally or alternatively, one or more characteristics stored by the threshold memory 308 may be stored in a lookup table. For example, the threshold memory 308 may store at least one of a first lookup table for threshold torques and a second lookup table for operating angles. Furthermore, in such examples, the value of the threshold torque stored in the first lookup table may vary based on the operating angle. For example, the threshold torque at a larger steering angle will be less than the threshold torque at a smaller steering angle.

[0039] In addition, the value of the threshold operating angle stored in the second lookup table can vary based on the applied torque. For example, the threshold operating angle when a large torque is applied can be less than the threshold operating angle for a smaller applied torque. In such cases, the relationship between the applied torque and the threshold operating angle and the relationship between the operating angle and the threshold torque are based on one or more characteristics of the first CV universal joint 206 and the second CV universal joint 208. In some examples, the relationship between the applied torque and the threshold operating angle can match the relationship between the threshold torque and the operating angle. In such examples, the threshold memory 308 can store only one lookup table that compares torque and operating angle.

[0040] The threshold memory 308 may be implemented by a volatile memory (e.g., synchronous dynamic random access memory (SDRAM), dynamic random access memory (DRAM), RAMBUS dynamic random access memory (RDRAM), etc.) and / or a non-volatile memory (e.g., flash memory). The threshold memory 308 may additionally or alternatively be implemented by one or more double data rate (DDR) memories, such as DDR, DDR2, DDR3, DDR4, mobile DDR (mDDR), etc. The threshold memory 308 may additionally or alternatively be implemented by one or more mass storage devices, such as a hard drive, an optical drive, a digital universal disk drive, etc. Although in the illustrated example, the threshold memory 308 is shown as a single database, the threshold memory 308 may be implemented by any number and / or type of databases. In addition, the data stored in the threshold memory 308 may be in any data format, such as, for example, binary data, comma-delimited data, tab-delimited data, structured query language (SQL) structures, etc.

[0041] A torque comparator 310 included or otherwise implemented by the comparator 306 compares the threshold torque received from the threshold memory 308 and the applied torque received from the torque determiner 302. In some examples, the torque comparator 310 uses a subtraction operation to determine the difference between the threshold torque and the applied torque (e.g., +3.4 ft-lbs, -5.2 ft-lbs, 0.0 ft-lbs, etc.). In such examples, a positive difference indicates that the applied torque is less than the threshold torque, and a negative difference indicates that the applied torque is greater than the threshold torque. In addition or alternatively, the torque comparator 310 uses a division operation to determine the ratio of the applied torque to the threshold torque (e.g., 1.25, 1.0, 0.68, etc.). In such examples, a ratio greater than one indicates that the applied torque exceeds the threshold torque, and a ratio less than one indicates that the applied torque is less than the threshold torque. In addition or alternatively, the torque comparator 310 can output at least one of the threshold torque received by the torque comparator 310 and the applied torque.

[0042] An angle comparator 312 included or otherwise implemented by the comparator 306 compares the threshold operating angle received from the threshold memory 308 and the operating angle received from the angle determiner 304. In some instances, the angle comparator 312 uses a subtraction operation to determine the difference between the threshold operating angle and the operating angle (e.g., +3.2 degrees, 0 degrees, -2.1 degrees, etc.). In such instances, a positive difference indicates that the operating angle is less than the threshold operating angle, and a negative difference indicates that the operating angle is greater than the threshold operating angle. In addition or alternatively, the angle comparator 312 uses a division operation to determine the ratio of the operating angle to the threshold operating angle (e.g., 1.4, 1.0, 0.95, etc.). In such instances, a ratio greater than one indicates that the operating angle exceeds the angle threshold, and a ratio less than one indicates that the operating angle is less than the threshold operating angle. In addition or alternatively, the angle comparator 312 can output at least one of the threshold operating angle and the operating angle received by the angle comparator 312.

[0043] In some examples, the comparator 306 receives calculations performed by at least one of the torque comparator 310 and the angle comparator 312. In response to at least one of the applied torque and the operating angle of at least one of the first CV joint 206 and the second CV joint 208 exceeding a threshold value (e.g., a limit), the comparator 306 further transmits a notification to the limiter 314 that a fault prevention routine must be executed to ensure the integrity (e.g., protection) of at least one of the first CV joint 206 and the second CV joint 208.

[0044] After each of the torque comparator 310 and the angle comparator 312 compares the torque applied to the first CV universal joint 206 and the second CV universal joint 208 with the threshold torque and the operating angle of the first CV universal joint 206 and the second CV universal joint 208 with the threshold operating angle, the applied torque and the operating angle are further transmitted to the limiter 314. The torque comparison is transmitted to the angle limiter 316, and the operating angle comparison is transmitted to the torque limiter 318. In some examples, the limiter 314 can also prioritize maintaining one of the applied torque or the operating angle. In some such examples, the limiter 314 can prioritize the applied torque over the operating angle and limit the operating angle before limiting the applied torque. In addition or alternatively, the limiter 314 can prioritize the operating angle over the applied torque and limit the applied torque before the operating angle.

[0045] An angle limiter 316 included in or otherwise implemented by the limiter 314 can limit the operating angle of at least one of the first CV universal joint 206 and the second CV universal joint 208 to a maximum allowable angle, the maximum allowable operating angle being determined based on at least one of testing and historical data. In some examples, limiting occurs in response to a torque applied to at least one of the first CV universal joint 206 and the second CV universal joint 208 exceeding a threshold. Limiting the operating angle can also include, when the vehicle 100 includes a ride height sensor 118, determining a maximum allowable steering angle at which the operating angle of each of the first CV universal joint 206 and the second CV universal joint 208 is less than or equal to the maximum value based on the current suspension position determined by the ride height sensor 118.

[0046] Alternatively, the vehicle 100 may not include or otherwise implement the ride height sensor 118. In such examples, determining the maximum allowable steering angle for which the operating angle of each of the first CV joint 206 and the second CV joint 208 is less than or equal to the maximum value may be based on a range of suspension travel governed by the geometry of the one or more suspension systems 116.

[0047] Once the maximum allowable steering angle is determined, the angle limiter 316 further communicates the maximum allowable steering angle value to the EPAS interface unit 320 .

[0048] An exemplary torque limiter 318 may be included in or otherwise implemented by the limiter 314. In addition, the torque limiter 318 can determine a maximum transmittable torque of at least one of the first CV universal joint 206 and the second CV universal joint 208 in response to the operating angle of at least one of the first CV universal joint 206 and the second CV universal joint 208 exceeding a threshold value. In some examples, the maximum transmittable torque is determined based on at least one of testing and historical data. In some examples, in addition to determining the maximum transmittable torque, the torque limiter 318 further attempts to apply a torque commanded by a user of the vehicle 100.

[0049] In such instances, attempting to apply the command torque also includes determining a differential torque between the command torque and the maximum transmittable torque. In addition, the torque limiter 318 can redistribute the differential torque to the unrestricted wheels of the vehicle 100. In some instances, if the vehicle 100 is a 4WD vehicle, the torque limiter 318 can redistribute the differential torque to one or more non-steering wheels 104. Additionally or alternatively, if the vehicle 100 is a FWD vehicle, the torque limiter 318 can redistribute the differential wheel torque of the two steered wheels 102 using at least one of a smaller steering angle and a smaller suspension travel.

[0050] Once at least one of the maximum transmittable torque and the redistributed torque to be applied is determined, the torque limiter 318 further communicates the torque value to be applied to each of the steered wheels 102 and the non-steered wheels 104 to the powertrain interface unit 322 .

[0051] An exemplary EPAS interface unit 320 included in or otherwise implemented by the CV joint load controller 120 can interface with the EPAS system 112 of the vehicle 100. In some examples, the EPAS interface unit 320 can communicate the maximum allowable steering angle received from the angle limiter 316 to the EPAS system 112. In such examples, the EPAS system 112 further ensures that the steering angle does not exceed the maximum allowable steering angle.

[0052] Additionally or alternatively, the EPAS interface unit 320 may monitor the EPAS system 112 to ensure that the steering angle does not exceed the maximum allowable steering angle. In such instances, when the steering angle commanded by the user of the vehicle 100 exceeds the maximum allowable steering angle, the EPAS interface unit 320 further overrides the steering angle commanded by the user of the vehicle 100 such that the steering angle of the vehicle 100 is limited to the maximum allowable steering angle. In some instances, the EPAS interface unit 320 may further notify the driver of the vehicle 100 that the steering angle of the vehicle 100 is limited through at least one of an audible or visual alarm.

[0053] An exemplary powertrain interface unit 322 included in or otherwise implemented by the CV joint load controller 120 is a device capable of interfacing with the powertrain controller 110 of the powertrain 106. In some examples, the powertrain interface unit 322 may communicate the maximum transmittable torque to the powertrain controller 110. In such examples, the powertrain controller 110 further ensures that the torque applied to the restricted CV joint does not exceed the maximum transmittable torque.

[0054] Additionally or alternatively, the powertrain interface unit 322 may directly command the powertrain controller 110 to apply a determined value of torque applied by the powertrain 106 to each of the steered wheels 102 and the non-steered wheels 104. In some examples, the powertrain interface unit 322 may further notify the driver of the vehicle 100 that the torque output by the powertrain 106 is limited through at least one of an audible or visual alarm.

[0055] although Figure 3 The exemplary CV joint load controller 120 includes: a torque determiner 302, an angle determiner 304, a comparator 306, a threshold memory 308, a torque comparator 310, an angle comparator 312, a limiter 314, an angle limiter 316, a torque limiter 318, an EPAS interface unit 320, and a powertrain interface unit 322. The exemplary CV joint load controller 120 disclosed herein can be used with any number of torque determiners 302, angle determiners 304, comparators 306, threshold memories 308, torque comparators 310, angle comparators 312, limiters 314, angle limiters 316, torque limiters 318, EPAS interface units 320, and powertrain interface units 322.

[0056] Although Figure 3 The implementation is shown in Figure 1 The exemplary embodiment of the exemplary CV joint load controller 120 is, however, Figure 3One or more of the elements, processes and / or devices shown in the example may be combined, divided, rearranged, omitted, eliminated and / or implemented in any other manner. In addition, the example torque determiner 302, the example angle determiner 304, the example comparator 306 (which in some examples may include an example threshold memory 308, an example torque comparator 310 and an example angle comparator 312), the example limiter 314 (which in some examples may include an example angle limiter 316 and an example torque limiter 318), the example EPAS interface unit 320 and the example powertrain interface unit 322 and / or more generally, Figure 1 The exemplary CV gimbal load controller 120 may be implemented by hardware, software, firmware, and / or any combination of hardware, software, and / or firmware. Thus, for example, the exemplary torque determiner 302, the exemplary angle determiner 304, the exemplary comparator 306 (which may include, in some examples, an exemplary threshold memory 308, an exemplary torque comparator 310, and an exemplary angle comparator 312), the exemplary limiter 314 (which may include, in some examples, an exemplary angle limiter 316 and an exemplary torque limiter 318), the exemplary EPAS interface unit 320, and the exemplary powertrain interface unit 322, and / or more generally, the exemplary CV gimbal load controller 120 may be implemented by one or more analog or digital circuits, logic circuits, programmable processors, application specific integrated circuits (ASICs), programmable logic devices (PLDs), and / or field programmable logic devices (FPLDs). When reading this patent to cover any device or system claims that are purely software and / or firmware implementations, the example torque determiner 302, the example angle determiner 304, the example comparator 306 (which in some instances may include the example threshold memory 308, the example torque comparator 310, and the example angle comparator 312), the example limiter 314 (which in some instances may include the example angle limiter 316 and the example torque limiter 318), the example EPAS interface unit 320, and the example powertrain interface unit 322 are expressly defined herein as comprising a non-transitory computer-readable storage device or storage disk, such as a memory, a digital versatile disk (DVD), a compact disk (CD), a Blu-ray disk, etc., including software and / or firmware. Furthermore, except Figure 4 In addition to or in lieu of what is shown in the figure, Figure 1 The example CV joint load controller 120 may also include one or more elements, processes and / or devices, and / or may include more than one of any or all of the illustrated elements, processes and devices.

[0057] Figures 4 to 6 The diagram shows a method for implementing Figure 1Flowchart of an exemplary method of an exemplary CV universal joint load controller 120. In this example, the method can be implemented using machine-readable instructions, which include instructions for a processor (such as the following combined Figure 7 The program may be embodied in software stored on a non-transitory computer-readable storage medium such as a CD-ROM, floppy disk, hard drive, digital versatile disk (DVD), Blu-ray disk, or memory associated with the processor 712, but the entire program and / or portions thereof may alternatively be executed by a device other than the processor 712 and / or embodied in firmware or dedicated hardware. In addition, although reference is made to Figures 4 to 6 The flowchart shown in describes an exemplary procedure, but many other methods of implementing the exemplary CV gimbal load controller 120 may alternatively be used. For example, the order of execution of the blocks may be changed, and / or some of the blocks described may be changed, eliminated, or combined. Additionally or alternatively, any or all of the blocks may be implemented by one or more hardware circuits (e.g., discrete and / or integrated analog and / or digital circuits, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), comparators, operational amplifiers (op-amps), logic circuits, etc.) that are structured to perform corresponding operations without executing software or firmware.

[0058] As mentioned above, Figures 4 to 6The exemplary processes of can be implemented using coded instructions (e.g., computer and / or machine readable instructions) stored on a non-transitory computer and / or machine readable medium (such as a hard drive, flash memory, read-only memory, compact disk, digital versatile disk, cache, random access memory, and / or any other storage device or storage disk where information is stored for any duration (e.g., for a long time, permanently, for brief instances, for temporary buffering, and / or for caching information)). As used herein, the term non-transitory computer readable medium is expressly defined to include any type of computer readable storage device and / or storage disk, and excludes propagating signals and excludes transmission media. "Include" and "comprising" (and all forms and tenses thereof) are used herein as open-ended terms. Therefore, whenever a claim lists any content that follows any form of "include" or "comprise" (e.g., comprises, includes, comprising, including, etc.), it should be understood that additional elements, terms, etc. may be present without exceeding the scope of the corresponding claim. As used herein, when the phrase "at least" is used as a transitional term in the preamble of a claim, it is open ended in the same manner that the terms "comprising" and "including" are open ended.

[0059] Figure 4 The example method 400 begins at block 402 . At block 402 , the example torque determiner 302 determines a torque applied to at least one of the first CV joint 206 and the second CV joint 208 based on a signal received from the powertrain controller 110 .

[0060] At block 404, the example angle determiner 304 determines an operating angle of at least one of the first CV joint 206 and the second CV joint 208. In some examples, the operating angle is based on at least one of a steering angle based on a signal received from the steering angle sensor 114 and a suspension position based on a signal received from the ride height sensor 118.

[0061] At box 406, in response to completing the determination of each of the torque applied to at least one of the first CV universal joint 206 and the operating angle, the comparator 306 evaluates the operating condition of at least one of the first CV universal joint 206 and the second CV universal joint 208. Evaluating the operating condition also includes comparing the torque threshold and the operating angle threshold stored in the threshold memory 308 with the applied torque and operating angle values ​​previously determined at boxes 402 and 404, respectively. In some examples, the comparison can produce a difference between the threshold and the operating value (e.g., +1.2 ft-lbs, -3.4 ft-lbs, +2.5 degrees, -4.6 degrees, etc.). Additionally or alternatively, the comparison can produce a ratio between the threshold and the operating value (e.g., 0.75, 0.95, 1.0, 1.1, 1.25, etc.).

[0062] At box 408, the comparator 306 determines whether a fault prevention routine is enabled for at least one of the first CV universal joint 206 and the second CV universal joint 208. Alternatively, the determination may be accomplished by the limiter 314. In some examples, determining whether to enable the fault prevention routine also includes determining whether a difference or ratio between a threshold and an operating value of at least one of the applied torque and the operating angle calculated at box 406 indicates that one or more of the applied torque and the operating angle exceeds the threshold. In response to neither the applied torque nor the operating angle exceeding the threshold, processing transfers to box 410, where the comparator 306 transmits a notification indicating that the subsystem of the vehicle 100 maintains normal operation, and processing of the exemplary method 400 returns to box 402. Alternatively, in response to at least one of the applied torque and the operating angle exceeding the threshold, processing transfers to box 412.

[0063] In response to determining that the fault prevention routine is enabled at block 412, comparator 306 determines which CV joint characteristic causes the fault prevention routine to be enabled at block 408. In response to determining that the operating angle exceeds the threshold, processing moves to block 414, in conjunction with Figure 5 As further described in detail, the torque applied to the CV joint is limited. Alternatively, in response to determining that the operating angle does not exceed the threshold, it is known that the torque applied to the CV joint exceeds the threshold. In such examples, processing transfers to box 416, combined with Figure 6 As described in further detail, the operating angle of the CV joint is limited. In response to completion of at least one of frame 414 or frame 416, processing transfers to frame 410 of the exemplary method 400.

[0064] An exemplary method may be performed to limit the torque applied to the CV joint ( Figure 4 , block 414), Figure 5It is shown in FIG. 1 that the torque applied to the CV joint is limited due to the large operating angle of the CV joint. Referring to the previous drawings and related descriptions, Figure 5 An exemplary method of includes starting execution at block 502, where the torque limiter 318 communicating via the powertrain interface unit 322 commands the powertrain controller 110 to limit the torque of the steered wheels 102. Additionally, the steered wheels 102 may be coupled to at least one of the first CV joint 206 and the second CV joint 208 in which the fault prevention routine is enabled, and the applied torque is limited to the maximum transmittable torque.

[0065] At box 504 , the torque limiter 318 determines the difference torque (eg, +3.5 ft-lbs, +6.2 ft-lbs, etc.) between the commanded torque, which in some examples is commanded by at least one of a user of the vehicle 100 or a computer algorithm, and the maximum allowable torque.

[0066] At block 506, the powertrain interface unit 322 determines whether it is desired to attempt to redistribute the difference between the commanded torque and the maximum transmittable torque calculated at block 504. In response to determining that it is desired to attempt to redistribute the differential torque, processing proceeds to block 508. Alternatively, in response to determining that it is not desired to attempt to redistribute the differential torque, the torque output by the powertrain 106 is limited, and processing proceeds to block 514.

[0067] At box 508, the torque limiter 318 determines whether the vehicle 100 is a 4WD vehicle capable of distributing the torque load to one or more non-steering wheels 104. In response to determining that the vehicle 100 is a 4WD vehicle, the process transfers to box 510. Alternatively, in response to determining that the vehicle 100 is not a 4WD vehicle (e.g., the vehicle 100 is a FWD vehicle), the process transfers to box 512.

[0068] At box 510 , the torque limiter 318 , communicating via the powertrain interface unit 322 , commands the 4WD vehicle's powertrain controller 110 to redistribute the differential torque determined by the torque limiter 318 at box 504 to one or more non-steering wheels 104 of the vehicle 100 .

[0069] At box 512, the torque limiter 318, which communicates via the powertrain interface unit 322, commands the powertrain controller 110 of the FWD vehicle to redistribute the differential torque determined by the torque limiter 318 at box 504 to the smaller steering wheels of the one or more steering wheels 102 of the vehicle 100. After completing at least one of box 510 and box 512, the process transfers to Figure 5 Block 514 of the exemplary method.

[0070] At box 514, the angle comparator 312 determines whether the operating angle of the CV joint still exceeds the threshold. In response to the operating angle of the CV joint continuing to exceed the threshold, processing transfers to box 502, where the torque limiter 318 communicating via the powertrain interface unit 322 continues to limit the torque applied to the CV joint.

[0071] Alternatively, in response to the angle comparator 312 determining that the operating angle of the CV joint no longer exceeds the threshold, processing returns to block 410 of the exemplary method 400, as shown. Figure 4 shown.

[0072] An exemplary method may be performed to limit the operating angle of a CV joint ( Figure 4 , block 416), Figure 6 FIG. 1 shows that the operating angle applied to the CV joint is limited due to the large torque applied to the CV joint. Referring to the previous drawings and related descriptions, Figure 6 The exemplary method of begins execution at block 602, where the angle limiter 316 determines whether one or more suspension systems 116 implement or otherwise include a ride height sensor 118. In response to determining that one or more suspension systems 116 do not include or otherwise implement a ride height sensor 118, processing moves to block 604. Alternatively, in response to determining that one or more suspension systems 116 do include a ride height sensor 118, processing moves to block 606.

[0073] At block 604, the angle limiter 316 determines a maximum allowable steering angle based on the maximum allowable operating angle of the first CV joint 206 and the second CV joint 208, which is based on the maximum travel of the suspension system 116 (i.e., the suspension system 116 has the greatest impact on the operating angle of the CV joints). In doing so, the angle limiter 316 ensures that the operating angle of each of the first CV joint 206 and the second CV joint 208 does not exceed a maximum value at the determined maximum allowable steering angle, regardless of the position of the suspension system 116.

[0074] Alternatively, at block 606 , the angle limiter 316 determines a maximum allowable steering angle based on the current position of the suspension system 116 as determined by the ride height sensor 118 .

[0075] At block 608, the angle limiter 316 communicating via the EPAS interface unit 320 commands the EPAS system 112 to limit the steering angle of the steered wheels 102 coupled to the first CV universal joint 206 and the second CV universal joint 208 to the maximum allowable operating angle determined by at least one of blocks 604 and 606. After the steering angle limitation of the steered wheels 102 is completed at block 608, the process transfers to Figure 6Block 610 of the exemplary method.

[0076] At box 610 , the torque comparator 310 determines whether the torque applied to the CV joint still exceeds the threshold. In response to the torque applied to the CV joint continuing to exceed the threshold, processing transfers to box 602 , where the angle limiter 316 determines whether one or more suspension systems 116 implement or otherwise include a ride height sensor 118 .

[0077] Alternatively, in response to the torque comparator 310 determining that the torque applied to the CV joint no longer exceeds the threshold, processing returns to block 410 of the exemplary method 400, as shown. Figure 4 shown.

[0078] Figure 7 Is able to execute instructions to implement Figures 4 to 6 Methods to implement Figure 3 The processor platform 700 may be, for example, a server, a personal computer, a mobile device (e.g., a mobile phone, a smart phone, a tablet computer (such as an iPad) TM )), personal digital assistant (PDA), Internet appliance, DVD player, CD player, digital video recorder, Blu-ray player, game console, personal video recorder, set-top box, or any other type of computing device.

[0079] The processor platform 700 of the illustrated example includes a processor 712. The processor 712 of the illustrated example is hardware. For example, the processor 712 can be implemented by one or more integrated circuits, logic circuits, microprocessors, or controllers from any desired series or manufacturer. The hardware processor can be a semiconductor-based (e.g., silicon-based) device. In this example, the processor implements the exemplary torque determiner 302, the exemplary angle determiner 304, the exemplary comparator 306 (in some examples, it can include the exemplary torque comparator 310 and the exemplary angle comparator 312), the exemplary limiter 314 (in some examples, it can include the exemplary angle limiter 316 and the exemplary torque limiter 318), the exemplary EPAS interface unit 320, and the exemplary powertrain interface unit 322.

[0080] The processor 712 of the illustrated example includes a local memory 713 (e.g., a cache). The processor 712 of the illustrated example communicates with a main memory including a volatile memory 714 and a non-volatile memory 716 via a bus 718. The volatile memory 714 may be implemented by a synchronous dynamic random access memory (SDRAM), a dynamic random access memory (DRAM), a RAMBUS dynamic random access memory (RDRAM), and / or any other type of random access memory device. The non-volatile memory 716 may be implemented by a flash memory and / or any other desired type of memory device. Access to the main memory 714, 716 is controlled by a memory controller.

[0081] The processor platform 700 of the illustrated example also includes an interface circuit 720. The interface circuit 720 may be implemented by any type of interface standard, such as an Ethernet interface, a universal serial bus (USB), and / or a PCI express interface.

[0082] In the example shown, one or more input devices 722 are connected to the interface circuit 720. The input devices 722 allow a user to enter data and / or commands into the processor 712. The input devices may be implemented by, for example, an audio sensor, a microphone, a camera (still or video), a keyboard, buttons, a mouse, a touch screen, a trackpad, a trackball, an isopoint device, and / or a voice recognition system.

[0083] One or more output devices 724 are also connected to the interface circuit 720 of the illustrated example. The output device 724 can be implemented, for example, by a display device (e.g., a light emitting diode (LED), an organic light emitting diode (OLED), a liquid crystal display, a cathode ray tube display (CRT), a touch screen, a tactile output device, a printer, and / or a speaker). Therefore, the interface circuit 720 of the illustrated example typically includes a graphics driver card, a graphics driver chip, and / or a graphics driver processor.

[0084] The interface circuitry 720 of the illustrated example also includes communication devices, such as transmitters, receivers, transceivers, modems, and / or network interface cards, to facilitate the exchange of data with an external machine (e.g., any type of computing device) via a network 726 (e.g., an Ethernet connection, a digital subscriber line (DSL), a telephone line, a coaxial cable, a cellular telephone system, etc.).

[0085] The processor platform 700 of the illustrated example also includes one or more mass storage devices 728 for storing software and / or data. Examples of such mass storage devices 728 include floppy disk drives, hard disk drives, optical disk drives, Blu-ray disk drives, RAID systems, and digital versatile disk (DVD) drives.

[0086] For implementation Figures 4 to 6 The coded instructions 732 of the method may be stored in the mass storage device 728, in the volatile memory 714, in the non-volatile memory 716, and / or on a removable tangible computer-readable storage medium (such as a CD or DVD).

[0087] From the foregoing, it should be appreciated that exemplary methods, apparatus, and articles of manufacture have been disclosed that ensure the integrity of a rotatable coupling, such as a CV joint disposed in a vehicle, during periods of large operating angles of the coupling and also during periods of large torques applied to the coupling by limiting at least one of the operating angle and the torque applied to the coupling. Furthermore, in the event that the applied torque is limited, the torque can be redistributed to ensure that the commanded torque is maintained.

[0088] Although certain exemplary methods, apparatus, and articles of manufacture have been disclosed herein, the scope of coverage of this patent is not limited thereto. On the contrary, this patent covers all methods, apparatus, and articles of manufacture fully within the scope of the claims of this patent.

[0089] According to the present invention, a device is provided, which includes: a comparator, which determines whether at least one of the torque or the angle exceeds a threshold value based on at least one of the angle of a rotatable coupling or the torque applied to the coupling; and a limiter, which is used to limit at least one of the angle or the torque when at least one of the torque or the angle exceeds the threshold value.

[0090] According to one embodiment, the threshold value is based on characteristics of the coupling.

[0091] According to one embodiment, the angle of the coupling is based on at least one of the steering angle or the suspension position.

[0092] According to one embodiment, the steering angle is limited by an electronic power steering system.

[0093] According to one embodiment, the above invention is further characterized in that the torque applied to the coupling is based on a user-commanded torque.

[0094] According to one embodiment, the limiter is further configured to distribute additional torque to the non-steered wheels when the user-commanded torque is greater than a threshold.

[0095] According to one embodiment, the above invention is further characterized by maintaining the torque applied to the coupling in preference to maintaining the angle of the coupling.

[0096] According to the present invention, a device is provided, which has a constant velocity (CV) universal joint load controller, the controller is used to evaluate at least one of the torque applied to the CV universal joint or the angle of the CV universal joint, and wherein the controller is used to limit at least one of the torque applied to the CV universal joint or the angle of the CV universal joint when at least one of the torque applied to the CV universal joint or the angle of the CV universal joint exceeds a threshold.

[0097] According to one embodiment, the threshold is based on characteristics of the CV joint.

[0098] According to one embodiment, the constant velocity joint load controller further includes: an angle comparator for comparing the angle of the CV joint with a threshold operating angle; and a torque comparator for comparing the torque applied to the CV joint with a threshold torque.

[0099] According to one embodiment, the constant velocity joint load controller further includes: an angle limiter for limiting the angle of the CV joint to a maximum allowable angle when the torque applied to the CV joint exceeds a threshold value; and a torque limiter for limiting the torque applied to the CV joint to a maximum transmittable torque when the angle of the CV joint exceeds a threshold value.

[0100] According to one embodiment, the angle of the CV joint is based on at least one of the steering angle or the suspension position.

[0101] According to one embodiment, the torque applied to the CV joint is based on a user commanded torque.

[0102] According to one embodiment, the constant velocity joint load controller is further configured to distribute additional torque to the non-steering wheels when the user-commanded torque is greater than a threshold.

[0103] According to the present invention, a method is provided, the method having the following steps: measuring at least one of the angle of a rotatable coupling or the torque applied to the coupling; determining whether at least one of the torque applied to the coupling or the angle of the coupling exceeds a threshold value; and in response to at least one of the torque applied to the coupling or the angle of the coupling exceeding the threshold value, limiting at least one of the angle of the coupling or the torque applied to the coupling.

[0104] According to one embodiment, the threshold value is based on characteristics of the coupling.

[0105] According to one embodiment, the angle of the coupling is based on at least one of the steering angle or the suspension position.

[0106] According to one embodiment, the torque applied to the gimbal is based on a user commanded torque.

[0107] According to one embodiment, in response to a user-commanded torque being greater than a threshold, a difference between the commanded torque and the threshold is redistributed to at least one of the non-steering wheels or the less-steering wheels.

[0108] According to one embodiment, maintaining the angle of the gimbal takes precedence over maintaining the torque applied to the gimbal.

Claims

1. A device comprising: a comparator that determines whether at least one of the torque or the angle exceeds a threshold based on an angle of the rotatable coupling or a torque applied to the coupling by a powertrain; as well as Limiters are used to: When the angle exceeds an angle threshold, limiting the torque; and The angle is limited when the torque exceeds a torque threshold and the angle does not exceed an angle threshold.

2. The apparatus of claim 1, wherein the threshold is based on a characteristic of the coupling.

3. The apparatus of claim 1, wherein the angle of the coupling is based on at least one of a steering angle or a suspension position.

4. The apparatus of claim 3, wherein the steering angle is limited by an electronic power steering system.

5. The apparatus of claim 1, wherein the torque applied to the coupling is based on a user-commanded torque.

6. The apparatus of claim 5, wherein the limiter is further configured to distribute additional torque to non-steer wheels when the torque commanded by the user is greater than the threshold.

7. The apparatus of claim 1, wherein maintaining the torque applied to the coupling takes precedence over maintaining the angle of the coupling.

8. A device comprising: A constant velocity (CV) joint load controller for evaluating a torque applied to a CV joint by a powertrain and an angle of the CV joint, and wherein the controller is used to limiting the torque applied to the CV joint when the angle of the CV joint exceeds an angle threshold; and The angle of the CV joint is limited when the torque applied to the CV joint exceeds a torque threshold and the angle of the CV joint does not exceed an angle threshold.

9. The apparatus of claim 8, wherein the threshold is based on a characteristic of the CV joint.

10. The apparatus of claim 8, wherein the constant velocity joint load controller further comprises: an angle comparator for comparing the angle of the CV joint to a threshold operating angle; as well as A torque comparator is used to compare the torque applied to the CV joint with a threshold torque.

11. The apparatus of claim 8, wherein the constant velocity joint load controller further comprises: an angle limiter for limiting the angle of the CV joint to a maximum allowable angle when the torque applied to the CV joint exceeds the threshold value; as well as A torque limiter is used to limit the torque applied to the CV joint to a maximum transmittable torque when the angle of the CV joint exceeds the threshold value.

12. The apparatus of claim 8, wherein the angle of the CV joint is based on at least one of a steering angle or a suspension position.

13. The apparatus of claim 8, wherein the torque applied to the CV joint is based on a user-commanded torque.

14. The apparatus of claim 13, wherein the constant velocity joint load controller further distributes additional torque to non-steering wheels when the torque commanded by the user is greater than the threshold.

15. The apparatus of claim 8, wherein the constant velocity joint load controller maintains the angle of the CV joint in preference to maintaining the torque applied to the CV joint.

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