Drive axle system for determining a pinion wheel torque

Abstract

Drive axle system comprising: a displacement sensor coupled to a pinion input flange and configured to generate axial displacement data corresponding to the pinion input flange, wherein the pinion input flange is directly coupled to an angled pinion gear; and a controller that contains instructions stored in memory that, when executed, cause the controller to: Determining a torque at the pinion input flange based on the axial displacement data; wherein the pinion input flange is arranged outside a differential housing.

Description

TECHNICAL FIELD

[0001] This description relates to a drive axle system. More specifically, the description relates to a method for determining the torque acting on a pinion input flange. BACKGROUND AND SUMMARY

[0002] Powertrains are included in certain vehicles. Powertrains derive their mechanical power from an internal combustion engine or an electric motor in various powertrain architectures. Some vehicle control strategies require torque measurements at specific points in the powertrain.

[0003] US 10,067,015 B2 to Lee et al. discloses a torque sensor arranged at a connection between an input shaft and an output shaft. The torque sensor has a complex design including a magnetic field generator, a collector that detects the magnetic field, and a shielding ring located between the magnetic field generator and the collector, among other components.

[0004] The inventors recognized several problems with Lee's torque sensor device and other prior torque sensors and corresponding systems. Magnetic and other types of torque sensors can be complex and expensive when used in some vehicles. In general, the inventors recognized the need to provide a less complex torque measurement device that can be quickly and effectively integrated into a variety of vehicle platforms. The inventors also recognized the need to efficiently determine the mechanical power transmitted to the drive axles.

[0005] To overcome the above challenges, the inventors have developed a drive axle system that can at least partially overcome the challenges. In one example, the drive axle system includes a displacement sensor coupled to a pinion input flange and configured to generate axial displacement data corresponding to the pinion input flange, which is directly coupled to an angled pinion gear. The drive axle system further includes a controller configured to determine a torque at the pinion input flange based on the axial displacement data. In the drive axle system, the pinion input flange is arranged outside a differential housing. Thus, the torque applied to the pinion gear can be determined quickly and efficiently using an axial displacement sensor, which can be installed more efficiently due to its location in the drive axle.

[0006] In another example, the drive axle system includes an angular velocity sensor coupled to the pinion input flange and configured to generate angular velocity data associated with the pinion input flange. In such an example, the angled pinion gear meshes with a ring gear in a differential, and the controller is configured to determine power transmitted through the pinion input flange based on the torque and speed of the pinion input flange. Consequently, the power transmitted through the pinion input flange can be efficiently calculated using a set of sensors that can be incorporated into a variety of vehicle platforms if desired without excessive machining.

[0007] It should be understood that the above summary is intended to introduce, in simplified form, a selection of concepts that are further explained in the detailed description. It is not intended to identify important or essential features of the claimed subject matter, the scope of which is clearly defined by the claims following the detailed description. Furthermore, the claimed subject matter is not limited to implementations that address the disadvantages noted above or elsewhere in this disclosure. SHORT DESCRIPTION OF THE CHARACTERS Fig. 1 shows a vehicle with a drive axle system. Fig. 2-4 show various detailed views of the drive axle system, which in Fig. 1 is shown. Fig. 5 shows a detailed view of a pinion input flange in the drive axle system, which is shown in Fig. 1 is shown. Fig. Figure 6 shows an exemplary diagram illustrating the correlation between an axial displacement of a pinion input flange and a torque applied to the flange. Fig. 7 shows a method for operating a drive axle system. DETAILED DESCRIPTION

[0008] Described herein is a drive axle system configured to determine a torque applied to a pinion input flange (located in a driveline) using an axial displacement of the pinion input flange determined by a displacement sensor attached to the flange. From this torque determination, the power transmitted through the pinion input flange can be calculated based on the product of the torque and an angular velocity of the pinion input flange determined by an angular velocity sensor attached to the pinion input flange or the displacement sensor. By using a displacement sensor in the system, the complexity of the system can be reduced compared to vehicle systems that use more complex torque sensors, such as magnetic torque sensors. The pinion input flange is located outside a differential housing.This allows the sensors to be attached to the flange quickly and efficiently, increasing manufacturing efficiency. Furthermore, both the displacement sensor and the angular velocity sensor can be coupled to the pinion input flange without the need for component machining, further increasing system manufacturing efficiency and improving the system's applicability to a wider range of vehicle platforms.

[0009] Fig. 1 shows a vehicle 100 with a drivetrain 102. The drivetrain 102 includes a prime mover 104, which is rotationally coupled to a drivetrain 106 via a drivetrain 108, as shown by arrows 109. The drivetrain 106, or more specifically, the drivetrain 108, is rotatably connected to a drive axle system 110, and in particular, a pinion input flange 112, as shown by arrows 114. The mechanical connection between the drivetrain 108 and the drive axle system 110 will be discussed in more detail here. The drivetrain 106 may include a transmission (e.g., a multi-speed transmission).

[0010] The vehicle 100 may take a variety of forms, such as a light-duty, medium-duty, or heavy-duty vehicle. Furthermore, in one example, the prime mover 104 may be an internal combustion engine. In another example, the prime mover 104 may be an electric motor (e.g., a traction motor). In further examples, the powertrain may include both an internal combustion engine and an electric motor. Thus, in one example, the vehicle 100 may be a hybrid electric vehicle, in another example, a pure electric vehicle, or in another example, an internal combustion engine vehicle.

[0011] The drive axle system 110 includes a drive axle assembly 116. The drive axle system 110 includes the pinion input flange 112, which is directly coupled to an angled pinion gear 118. In the illustrated example, the pinion input flange 112 is directly coupled to a shaft 120 of the angled pinion gear 118 at a location external to the differential case 122.

[0012] The pinion input flange 112 has an outer surface 124 that is contoured to allow it to be attached to a suitable component of the drivetrain 108, e.g., a shaft, a joint, and the like. The outer surface 124 of the flange includes planar portions in the illustrated example. However, in other examples, the outer surface 124 may have other contours. The outer surface 124 may include openings for fasteners and / or other suitable structural features that allow the pinion input flange 112 to be attached to upstream components, which is discussed here with respect to Fig. 2. In the illustrated example, the shaft of pinion shaft 120 includes a portion disposed within an opening 126 of a portion of pinion input flange 112. However, other pinion gear designs have also been contemplated.

[0013] The differential housing 122 may be removably coupled to an axle housing 128. Fastening devices 130 (e.g., bolts or other suitable devices) may be used to removably secure the differential housing 122 and the axle housing 128. A differential may be enclosed in the space formed between the differential housing 122 and the axle housing 128. In addition, the differential housing 122 encloses a toothed portion of the angled pinion gear 118, which is shown here with respect to Fig. 3. The differential housing 122 may therefore serve as an access panel for internal components within the axle, such as the angled pinion gear 118, a differential, which will be discussed in more detail herein, and the like. The differential is configured to transmit mechanical power to the axle shafts and, under certain operating conditions, to enable speed differentiation between the axle shafts.

[0014] The drive axle system 110, in the illustrated example, also includes a steering assembly 132. For example, in one example, the drive axle system 110 may be a drive-steer axle. However, in other examples, the drive axle may be a non-steered axle. The steering assembly 132 may include a steering cylinder 134 and a steering linkage 136 that mechanically connects the steering cylinder 134 to the hub assemblies 138 to allow the pivot angle of the wheels connected to the hubs to be changed, for example, based on operator inputs. The steering linkage 136 may include shafts, joints, and the like to achieve the pivot angle adjustment function. The wheels may be coupled to the hub assemblies 138 via fasteners 140.

[0015] A pair of sensors can be coupled to the pinion input flange 112, which are located in the Fig. 3 and Fig. 5. These sensors allow the mechanical power transmitted to the angled pinion gear 118 via the flange to be efficiently determined using a sensor assembly that is efficient to install and, due to its design, can be incorporated into a variety of vehicle platforms, thus increasing the applicability and thus the customer appeal of the sensor assembly.

[0016] As in Fig. 1, the vehicle 100 may further include a control system 150 having a controller 152. The controller 152 may include a microcomputer with components such as a processor 154 (e.g., a microprocessor unit), input / output ports, an electronic storage medium 156 for executable programs and calibration values, e.g., a read-only memory chip, read-only memory, diagnostic memory, a data bus, and the like. The storage medium may be programmed with computer-readable data representing instructions executable by a processor to perform the methods, control techniques, etc. described herein, as well as other variations that are expected but not explicitly listed.Thus, instructions may be stored in the electronic storage medium 156 which, when executed by the processor 154, cause the controller 152 to perform the various method steps described herein.

[0017] The controller 152 may receive various signals from sensors 158 coupled to various areas of the vehicle 100, and in particular, the drive axle system 110. The sensors 158 may include, for example, an axial displacement sensor and an angular velocity sensor (discussed in more detail below), a pedal position sensor for detecting the actuation of a driver-operated pedal (e.g., an accelerator and / or brake pedal), driveline speed sensors, etc. An input device 160 (e.g., accelerator pedal, brake pedal, gear selector, combinations thereof, and the like) may also provide input signals indicative of the driver's intent for vehicle control.

[0018] After receiving the signals from the various sensors 158 from Fig. 1, the controller 152 processes the received signals and deploys various vehicle component actuators 162 to adjust the components based on the received signals and the instructions stored in the memory of the controller 152. For example, the controller 152 may receive an accelerator pedal signal indicating the driver's request for an adjustment of the vehicle's acceleration. In response, the controller 152 may command the operation of the prime mover 104 to adjust the prime mover's power. The other controllable components in the vehicle may function in a similar manner, e.g., with respect to sensor signals, control commands, and actuator adjustment.

[0019] In Fig. 1 is just like in Fig. 2-5, an axis system is provided for reference. In one example, the y-axis may be a vertical axis (e.g., parallel to a gravity axis), the x-axis may be a lateral axis (e.g., a horizontal axis), and the z-axis may be a longitudinal axis. In other examples, the axes may have other orientations.

[0020] Fig. Figure 2 shows a detailed view of the interface between the pinion input flange 112 and the shaft 120 of the angled pinion gear 118 in the drive axle system 110. The outer side 124 of the pinion input flange 112 is in Fig. 2. The outer surface 124 includes, in the example shown, flat portions 200 and toothed portions 202. Additionally or alternatively, the flange may have openings, splines, and the like to facilitate attachment to the driveline. However, in other examples, other suitable outer surface profiles may be used. A radial shaft seal 204 may be disposed between the shaft 120 of the angled pinion gear 118 and the differential housing 122. Further, the differential housing 122 may include a base 206 attached to the axle housing 128 and an extension 208 extending from the base and shaped to, in some cases, enclose the angled pinion gear 118 and a ring gear in a differential. The steering assembly 132, including the steering cylinder 134 and the steering linkage 136, is shown in Fig. 2 is shown again.

[0021] Fig. Figure 3 shows a cross-sectional view of the drive axle system 110. A differential 300 is depicted. The differential 300 includes a ring gear 302 that meshes with a toothed portion 304 of the angled pinion gear 118. The toothed portion 304 is angled relative to a rotational axis 305 of the pinion gear 118.

[0022] The ring gear 302 is coupled to a differential housing 306, which rotates a pinion shaft 308 having pinion gears 310 (e.g., ring gears) rotationally coupled thereto and rotating about an axis 312. The pinion gears 310 mesh with the side gears 314, which are profiled (e.g., toothed) to be attached to the axle shafts 316. This arrangement enables, under certain operating conditions, a speed differentiation between the side gears 314 and thus the axle shaft. In the example shown, the differential 300 includes a locking device 318 with plates 320 and other components configured to block co-rotation of the side gears 314 in the engaged state. In this way, the differential 300 may be a lockable differential that can be actively controlled to engage and disengage the locking device and thus increase the vehicle's traction. However, another type of differential may also be used, e.g.an open differential, a limited-slip differential, a torque-splitting differential, and the like.

[0023] In the example shown, a pair of bearings 322 (including bearings 324 and 326) is coupled to the pinion shaft 120 of the angled pinion gear 118. Bearings 324 and 326 are thrust bearings (e.g., spherical roller thrust bearings) that, in the example shown, accommodate the axial forces from the drive train and the ring gear 302. In the example shown, bearings 324 and 326 are arranged to respond to loads occurring in opposite axial directions.

[0024] An axial displacement sensor 328 is in Fig. 3. The axial displacement sensor 328 is configured to generate axial displacement data indicative of an axial displacement 330 between the pinion input flange 112 caused by varying degrees of torque transmitted across the flange. Specifically, the axial displacement 330 may be the axial distance between a surface 332 of the differential case 122 and an inner surface 334 of the pinion input flange 112. However, other suitable surfaces or locations within the case and flange may be used to determine the axial displacement. The axial displacement 330 is measured along an axis that, in the example shown, is parallel to the z-axis. However, other orientations with respect to the axial displacement measurement are also possible.

[0025] An angular velocity sensor 336 is in Fig. 3. Angular velocity sensor 336 is configured to generate angular velocity data indicative of an angular velocity of pinion input flange 112 and thus pinion gear 118. Angular velocity sensor 336 may be either directly coupled to pinion input flange 112 or coupled to the flange via a connection to the displacement sensor, with various examples. Similarly, axial displacement sensor 328 may be directly coupled to pinion input flange 112 or to angular velocity sensor 336, which is directly coupled to pinion input flange 112. In the example shown, the axial displacement sensor 328 is directly coupled to a body 337 of the pinion input flange 112, and the angular velocity sensor 336 is coupled to the outer circumference of the axial displacement sensor.However, in other examples, the angular rate sensor 336 may be directly coupled to the flange body 337 and the axial displacement sensor 328 may be directly coupled to the rate sensor.

[0026] The displacement sensor 328 and the angular velocity sensor 336 are located outside the differential housing 122. Specifically, the displacement sensor 328 and the angular velocity sensor 336 may be disposed between the outer surface 332 of the differential housing 122 and an inner surface 338 of the pinion input flange 112. This allows for more efficient installation after assembly of the drive axle in terms of manufacturing. Furthermore, the sensors can be installed in the drive axle if desired without machining special mounting structures. This increases installation efficiency and improves system applicability.

[0027] In the illustrated example, the flange body 337 has an inner surface 340 that is in surface contact with an outer peripheral surface 342 of the pinion shaft 120. The body of the flange thus circumferentially encloses the pinion shaft. In particular, in one example, the body of the flange may be press-fitted onto the pinion shaft. However, other suitable fastening techniques between the flange body and the pinion shaft have also been contemplated, such as welding, or the components may be formed (e.g., machined) as a monolithic structure.

[0028] The radial shaft seal 204, which can optionally be integrated into the drive axle system 110, is also in Fig. 3. In addition, the axle housing is Fig. 3 has been omitted. However, it goes without saying that the fastening devices 130 can be used to fasten the differential housing 122 to the axle housing.

[0029] Fig. Figure 4 shows a cross-sectional view of the drive axle system 110, with the differential omitted to clarify the contours of the other components of the system. The toothed portion 304 of the angled pinion gear 118 is again shown along with the pinion shaft 120. In addition, the bearings 324 and 326, the differential housing 122, and the axle shaft housing 128 are again shown. Although the sensors in the system illustration in Fig. 4 have been omitted, it goes without saying that the sensors are coupled to the pinion input flange 112 when the system is assembled.

[0030] Bearings 324 and 326 each include an inner ring 400 and an outer ring 402 with roller elements 404 (e.g., tapered cylindrical rollers) disposed therebetween. Inner rings 400 are in surface contact with the outer peripheral surface 342 of pinion shaft 120. Conversely, outer rings 402 are in surface contact with an inner surface 406 of differential housing 122. Specifically, differential housing 122 may include internal recesses 408 shaped to mate with the outer rings. However, other differential housings may be used in other examples.

[0031] In Fig. 4, the body 337 of the pinion input flange 112 is shown again. As already mentioned, the body 337 in the example shown rests against the outer circumferential surface 342 of the pinion shaft 120. In addition, the pinion input flange 112 is arranged outside the differential housing 122, so that the sensors that are Fig. 5, can be installed quickly and efficiently during manufacture, maintenance, etc. In particular, the flange 112 is arranged outside a housing formed between the differential housing 122 and the axle shaft housing 128 that encloses the differential 300 (see Fig. 3).

[0032] As in Fig. 4, a retaining ring 410 and / or a nut 412 may also be coupled to an outer end 414 of the angled pinion gear 118 to securely and releasably attach the pinion input flange 112 to the pinion gear shaft 120. However, the flange may also be coupled to the pinion gear by other suitable techniques.

[0033] Fig. 5 shows a detailed view of the pinion input flange 112 and the sensor group 328 and 336. As in the Fig. In the example shown in Figure 5, the displacement sensor 328 is directly coupled to the body 337 of the pinion input flange 112, and the angular velocity sensor 336 circumferentially surrounds the displacement sensor and is directly coupled to it. However, in alternative examples, the sensors may be mounted at other suitable locations.

[0034] In Fig. 6, several prophetic use case correlations between the axial displacement between the differential housing and the pinion input flange and torque are illustrated in a graph 600. The drive axle systems described herein, and in particular the controllers, may utilize this type of axial displacement-torque correlation in a control strategy that uses torque, and in some cases power, as parameters to determine the setting of various controllable components in the driveline, such as the prime mover, the braking system, and the like. In practice, the torque-axial displacement correlation with respect to various operating conditions (e.g., a drive condition, a coast condition, a locked differential condition, an unlocked differential condition, etc.) may be stored in lookup tables and / or other suitable data structures within the controller.

[0035] The torque (T) is indicated on the abscissa and increases from left to right. The axial displacement (P) is indicated on the ordinate and increases from bottom to top. Zero values ​​are indicated on both the ordinate and abscissa, although no specific numerical positive and negative values ​​are given for the torque (T) and axial displacement (P).

[0036] Diagrams 602 show the correlation between torque and axial displacement in the coasting state. Conversely, diagrams 604 show the correlation between torque and axial displacement during driving. Line 606 marks the boundary between the coasting state and the driving state.

[0037] The following presents a method for determining the axial displacement relationship between the pinion input flange and the differential housing. This strategy can be performed on a test bench before the sensor set is integrated into a vehicle platform, to give a specific example. However, it should be understood that a variety of suitable methods can be used to determine the axial displacement-torque relationship before deploying the drive axle system described here. The correspondence can be determined, for example, in a modeling program. Furthermore, this strategy can be implemented in any of the drive axle systems described here or in combinations of the drive axle systems.

[0038] In the use case method for determining the correlation between torque and axial displacement, the zero values ​​of all digital displays of the test bench can be set to zero simultaneously using a CAN (Controller Area Network) signal. The system can then be rotated without torque. The system can then be stabilized in the zero torque state for a predetermined period of time (e.g., at least three gear revolutions or 10 seconds, in various examples). The torque in the system can then be slowly ramped up to a predetermined value (e.g., 25% in a specific use case). The system can then be held in the increasing torque state for a predetermined period of time (e.g., at least three gear revolutions or 10 seconds in various examples).The method may then include several steps for ramping and holding the torque, similar to the previous steps. The method may further include steps in which the torque is decreased by predetermined amounts and then held at that value for predetermined periods of time (the reverse of the ramping and holding steps) until the torque reaches zero. This cycle may be repeated a predetermined number of times in both the forward (e.g., drive side) and reverse (coast side) directions with the differential locked and unlocked. From this data, coefficients between the axial displacement and the torque for these various operating conditions can be determined. The correspondence between the coefficients and the operating conditions can be stored in lookup tables and / or other suitable data structures.However, other suitable methods can also be used to determine the correlation between torque and axial displacement.

[0039] Fig. 7 illustrates a method 700 for operating a drive axle system. In particular, the method may be used to determine the mechanical power transferred to the drive axle, which may then be utilized in other vehicle control systems. The method 700, as well as the other control schemes, control techniques, methods, etc. described herein, may be implemented with any of the drive axle systems and vehicles described herein, or combinations of drive axle systems and vehicles. However, in other examples, the controls and / or other control techniques, methods, etc. described herein may also be implemented by other suitable drive axle systems and / or vehicles.

[0040] At 702, the method includes receiving sensor data from the axial displacement sensor and the angular velocity sensor. For example, data indicating axial displacement between a pinion input flange and a differential housing may be sent to the controller from the axial displacement sensor, and data indicating the angular velocity of the flange may also be sent to the controller from the angular velocity sensor. As previously mentioned, these two sensors may be coupled to the flange.

[0041] At 704, the method includes determining a torque applied to the pinion input flange based on the axial displacement data received from the axial displacement sensor. For example, a lookup table or other data set storing the predetermined correlation between axial displacement and torque may be used for such a determination.

[0042] In step 706, the method includes determining a mechanical power transmitted through the pinion input flange based on the torque determined in step 704 and the angular velocity of the pinion input flange. For example, the angular velocity and torque may be multiplied to calculate the mechanical power. The method may further include operating the drive axle system and / or the driveline based on the mechanical power determined in step 706. The output speed of the prime mover may be adjusted based on the determined mechanical power. For example, the prime mover power may be increased if the mechanical power falls below a target value, and vice versa.In other examples, method 700 enables efficient determination of the torque and power applied to the pinion input flange and pinion gear using a set of sensors that can be effectively and efficiently installed in a variety of vehicles.

[0043] The technical effect of the drive axle system operating methods described here is to more efficiently calculate the mechanical power transmitted to a drive axle to increase the computational power of the control system, using a sensor system that is easier to install in a variety of vehicles.

[0044] Fig. 1-5 are drawn approximately to scale, except for the schematically illustrated components. However, other relative component dimensions may be used in other embodiments.

[0045] Fig.1-5 show example configurations with the relative arrangement of the various components. When these elements are in direct contact with one another or are directly coupled, they may be referred to as being in direct contact or directly coupled, respectively, in at least one example. Similarly, elements shown adjacent or proximate to one another may be adjacent or proximate to one another, in at least one example. For example, components that are in face-to-face contact with one another may be referred to as being in face-to-face contact. As another example, elements that are spaced apart from one another and have only a gap between them and no other components may be referred to as such in at least one example.In yet another example, elements that are arranged below / above each other, on opposite sides of each other, or to the left / right of each other may be referred to as such relative to each other. Further, in at least one example, as illustrated in the figures, a topmost element or point of an element may be referred to as a "top" of the component, and a bottommost element or point of the element may be referred to as a "bottom" of the component. As used herein, the terms top / bottom, upper / lower, above / below may refer to a vertical axis of the figures and may be used to describe the positioning of elements of the figures relative to each other. Thus, in one example, elements displayed above other elements are arranged vertically above the other elements.As another example, the shapes of the elements depicted in the figures may be referred to as such (e.g., circular, straight, flat, curved, rounded, beveled, angled, and the like). Furthermore, in one example, elements that are coaxial with one another may be referred to as such. Further, in at least one example, the depicted elements that intersect one another may be referred to as intersecting elements or as intersecting elements. Furthermore, an element depicted inside or outside another element may be referred to as such. In other examples, elements that are offset from one another may also be referred to as such. The term "substantially" may mean plus or minus five percent or less of the range or value, unless otherwise noted.

[0046] The invention is further described in the following paragraphs. In one aspect, a drive axle system is provided that includes a displacement sensor coupled to a pinion input flange and configured to generate axial displacement data corresponding to the pinion input flange, wherein the pinion input flange is directly coupled to an angled pinion gear; and a controller including instructions stored in memory that, when executed, cause the controller to determine a torque at the pinion input flange based on the axial displacement data; wherein the pinion input flange is disposed externally of a differential case. In one example, the pinion input flange may comprise a body circumferentially surrounding a shaft of the angled pinion gear.In another example, the drive axle system may further include an angular rate sensor coupled to the pinion input flange and configured to generate angular rate data associated with the pinion input flange, wherein the angled pinion gear meshes with a ring gear in a differential. In another example, the controller may include instructions stored in memory that, when executed, cause the controller to determine power transmitted through the pinion input flange based on the torque and speed of the pinion input flange. In another example, the angular rate sensor may circumferentially surround the displacement sensor. In another example, the pinion input flange may be disposed externally of a bearing coupled to a shaft of the angled pinion gear. In another example, the bearing may be a thrust bearing.In another example, the pinion input flange may be configured to be rotationally coupled to a drive shaft. In another example, the drive shaft may be rotationally coupled to an internal combustion engine. In another example, the drive shaft may be rotationally coupled to a traction motor. In another example, the differential housing may be directly coupled to an axle housing. In another example, the drive axle system may be a steering axle.

[0047] In another aspect, a method of operating a drive axle system is provided, comprising receiving axial displacement data from a displacement sensor coupled to a pinion input flange and determining a torque applied to the pinion input flange based on the axial displacement data; wherein the drive axle system comprises the displacement sensor and the pinion input flange directly coupled to an angled pinion gear. In one example, the method may further comprise determining an angular velocity of the pinion input flange based on angular velocity data from an angular velocity sensor directly coupled to the pinion input flange.In another example, the method may further include determining a power transmitted through the pinion input flange based on the torque and angular velocity of the pinion input flange. Furthermore, in one example, the pinion input flange may include a body circumferentially surrounding a shaft of the angled pinion gear. In another example, the pinion input flange may be disposed externally of a thrust bearing coupled to a shaft of the angled pinion gear.

[0048] In another aspect, a drive axle system is provided, comprising: a displacement sensor coupled to a pinion input flange and configured to generate axial displacement data corresponding to the pinion input flange, wherein the pinion input flange is directly coupled to an angled pinion gear that meshes with a ring gear of a differential; an angular velocity sensor coupled to the pinion input flange and configured to generate angular velocity data corresponding to the pinion input flange, wherein the angled pinion gear meshes with a ring gear in a differential; and a controller including instructions stored in memory that, when executed, cause the controller to: determine a power transmitted through the pinion input flange based on the axial displacement and the angular velocity of the pinion input flange;wherein the pinion input flange is disposed outside a differential housing. Furthermore, the pinion input flange may include a circumferential body enclosing the shaft of the angled pinion gear. In another example, the drive axle system may further include two opposed thrust bearings coupled to the shaft of the angled pinion gear.

[0049] In another embodiment, an axle assembly is provided that includes a pair of sensors disposed outside an axle housing enclosing a differential and axle shafts, the pair of sensors including a displacement sensor that generates data indicative of axial movement of a pinion input flange and a speed sensor that generates data indicative of rotational speed of the pinion input flange, and a controller configured to determine a torque applied to the pinion input flange based on the axial movement of the pinion input flange and to determine a mechanical power transmitted through the pinion input flange based on a product of the torque and the rotational speed.

[0050] The control methods and routines disclosed herein may be stored as executable instructions in non-transitory memory and executed by a drive axle system or vehicle system including the controller in combination with the various sensors and actuators. Additionally, portions of the methods may be physical actions performed in the real world to change the state of a device. The specific routines described herein may represent one or more processing strategies, such as event-driven, interrupt-driven, multitasking, multithreading, and the like. Thus, the various actions, operations, and / or functions illustrated may be performed in the order illustrated, in parallel, or, in some cases, without them.Accordingly, the order of processing is not required to achieve the features and advantages of the examples described herein, but is provided for convenience of illustration and description. One or more of the illustrated actions, operations, and / or functions may be performed repeatedly depending on the strategy used. Furthermore, the described actions, operations, and / or functions may graphically represent code to be programmed into the non-transitory memory of the computer-readable storage medium in the control system, wherein the described actions are carried out by execution of the instructions in a system that includes the various hardware components in combination with the electronic control system. One or more of the method steps described herein may also be omitted if desired.

[0051] It is to be understood that the invention is capable of various alternative orientations and sequences of steps unless expressly stated otherwise. It is also to be understood that the arrangements, devices, and methods illustrated in the accompanying drawings and described in the following description are merely examples of embodiments of the inventive concepts. Thus, specific dimensions, directions, or other physical characteristics with respect to the disclosed embodiments should not be construed as limitations unless expressly stated otherwise.

[0052] It should be understood that the configurations and operations disclosed herein are exemplary in nature and that these specific examples are not to be considered limiting, as numerous variations are possible. For example, the technology described above may be applied to axle assemblies incorporating various types of power sources, including various types of electric machines and / or internal combustion engines. The subject matter of the present disclosure includes all novel and non-obvious combinations and sub-combinations of the various systems and configurations, as well as other features, functions, and / or characteristics disclosed herein.

[0053] The following claims particularly point out certain combinations and sub-combinations that are considered novel and non-obvious. These claims may refer to "a" element or "a first" element, or the equivalent thereof. Such claims are to be construed as including the inclusion of one or more such elements, neither requiring nor excluding two or more such elements. Other combinations and sub-combinations of the disclosed features, functions, elements, and / or properties may be claimed by amending the present claims or by filing new claims in this or a related application. Such claims, whether broader, narrower, the same, or different in scope than the original claims, are also considered to be included within the subject matter of the present disclosure.

[0054] The above description is intended only to illustrate the principles of the invention. Furthermore, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and processes shown and described herein. Accordingly, all suitable modifications and equivalents are intended to be within the scope of the invention as defined by the following claims. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] US 10,067,015 B2

[0003]

Claims

[1] Drive axle system, comprising: a displacement sensor coupled to a pinion input flange and configured to generate axial displacement data corresponding to the pinion input flange, wherein the pinion input flange is directly coupled to an angled pinion gear; and a controller that contains instructions stored in memory that, when executed, cause the controller to: Determining a torque at the pinion input flange based on the axial displacement data; wherein the pinion input flange is arranged outside a differential housing. [2] The drive axle system of any one of claims 1, wherein the pinion input flange comprises a body circumferentially surrounding a shaft of the angled pinion gear. [3] Drive axle system according to one of the preceding claims, further comprising: an angular velocity sensor coupled to the pinion input flange and configured to generate angular velocity data associated with the pinion input flange, wherein the angled pinion gear meshes with a ring gear in a differential; and / or two opposing axial bearings are coupled to the shaft of the angled pinion wheel. [4] A drive axle system according to claim 3, wherein the controller includes instructions stored in memory which, when executed, cause the controller to: Determine the power transmitted through the pinion input flange based on the torque and speed of the pinion input flange. [5] A drive axle system according to claim 3 or 4, wherein the angular velocity sensor surrounds the displacement sensor in the circumferential direction. [6] A drive axle system according to any one of the preceding claims, wherein the pinion input flange is arranged outside a bearing coupled to a shaft of the angled pinion gear. [7] Drive axle system according to claim 6, wherein the bearing is a thrust bearing. [8] Drive axle system according to one of the preceding claims, wherein the pinion input flange is arranged to be rotationally coupled to a drive shaft. [9] Drive axle system according to claim 8, wherein the drive shaft is rotationally coupled to an internal combustion engine. [10] Drive axle system according to claim 8 or 9, wherein: the drive shaft is rotationally coupled to a traction motor; the differential housing is directly coupled to an axle shaft housing; and / or the drive axle system is a steering axle.

Images