Active suspension system

Abstract

This disclosure relates to an active suspension system. The suspension system includes a top mount, a bottom mount, a rigid housing, an air spring, and a linear actuator. The air spring transmits forces along a first load path between the top mount and the bottom mount. The air spring includes a pressurized chamber containing pressurized air that transmits the forces along the first load path. The linear actuator transmits forces along a second load path between the top mount and the bottom mount, parallel to the first load path. The rigid housing defines at least a portion of the pressurized chamber and transmits the forces along the second load path.

Description

[0001] Case Analysis

[0002] This application is a divisional application of Chinese invention patent application No. 201880030338.8, filed on April 27, 2018, entitled "Active Suspension System".

[0003] Cross-reference to related applications

[0004] This patent application claims the benefit of U.S. Provisional Patent Application No. 62 / 503,093, filed May 8, 2017, the entire disclosure of which is incorporated herein by reference. Technical Field

[0005] This disclosure relates to vehicles, and more specifically, to their suspension systems. Background Technology

[0006] Passenger vehicles include a suspension system that controls the transmission of forces, such as those from road disturbances, between the vehicle body and the wheels. Traditional suspension systems are passive systems, consisting of a spring-damper system where the springs and dampers have fixed characteristics. However, given varying road conditions and changing passenger preferences, this fixed characteristic may not be suitable for passenger comfort. Newer suspension systems include active suspensions, whose various characteristics can be controlled by a user (e.g., the vehicle's driver) or automatically in response to various detected conditions. For example, air spring suspension allows the driver to select the desired vehicle height. The damping characteristics provided by magnetorheological dampers may vary based on detected conditions, such as vehicle acceleration. Summary of the Invention

[0007] In one aspect, the suspension system includes a top mount, a bottom mount, a rigid housing, an air spring, and a linear actuator. The air spring transmits forces along a first load path between the top mount and the bottom mount. The air spring includes a pressurized chamber containing pressurized gas that transmits the forces along the first load path. The linear actuator transmits forces along a second load path between the top mount and the bottom mount, parallel to the first load path. The rigid housing defines at least a portion of the pressurized chamber and transmits the forces along the second load path.

[0008] The rigid housing can be connected to the top mount via an isolator that seals the pressurized chamber and transmits the force of the second load path between the rigid housing and the top mount.

[0009] A linear actuator and a rigid housing can form a first piston assembly movable relative to the bottom mount of the air spring, while a top mount can form a second piston assembly movable relative to the bottom mount of the air spring. The effective piston areas of the first and second piston assemblies can be approximately equal.

[0010] A rigid housing can be coupled to a bottom mounting bracket via a flexible diaphragm that seals the pressurization chamber and allows movement of the first piston assembly relative to the bottom mounting bracket, while an isolator allows movement of the second piston assembly relative to the rigid housing. The pressurization chamber can be defined by a top mounting bracket, an isolator, a rigid housing, a flexible diaphragm, and a bottom mounting bracket.

[0011] The suspension system may further include a second rigid housing coupled to the undermount bracket, wherein the flexible diaphragm is connected to the rigid housing and the second rigid housing to couple the rigid housing to the undermount bracket, and the second rigid housing defines a lower chamber of the pressurization chamber.

[0012] Linear actuators may include motors having a rotor and a stator housed in a pressurized chamber.

[0013] The stator can contact the inner surface of the rigid housing.

[0014] The rigid shell can be a first rigid shell, and the suspension system also includes a second rigid shell surrounding the first rigid shell, and the first rigid shell is connected to the second rigid shell via an upper isolator and a lower isolator, and the force of the second load path is transmitted between them via the upper isolator and the lower isolator.

[0015] Alternatively, the rigid housing may be a first rigid housing, and the suspension system may also include a second rigid housing surrounded by the first rigid housing, and the second rigid housing is coupled to the linear actuator and the first rigid housing to transmit the force of the second load path between them.

[0016] The pressurization chamber may include an upper chamber and a lower chamber, wherein the pressurized gas flowing between the upper chamber and the lower chamber is surrounding or passing through at least one of the linear actuators.

[0017] A rigid housing may be radially spaced from and around the linear actuator to define a circumferential gap between them, through which pressurized gas flows between the upper and lower chambers. Alternatively or additionally, pressurized gas flows between the upper and lower chambers through the inner housing of the linear actuator.

[0018] A linear actuator can be a ball screw actuator with a ball nut and a shaft, and a motor selectively applies torque to the ball nut to apply force to the shaft via a second load path.

[0019] Linear actuators may include ball splines that prevent the shaft from rotating relative to a rigid housing.

[0020] The vehicle may include a body, one or more unsprung components, and one or more suspension systems, each of which has a top mount connected to the body, and each of the suspension systems has a top mount connected to one of the unsprung components.

[0021] The vehicle may include a pressurized air source in fluid communication with one or more suspension systems for supplying pressurized gas to their pressurization chambers; and a control system for controlling linear actuators of one or more suspension systems in response to dynamic loads between the vehicle body and its coupled unsprung components.

[0022] The vehicle may include four unsprung components and four suspension systems.

[0023] The suspension system includes springs and a ball screw actuator. The springs are configured to form a first load path between the vehicle body and the unsprung components of the vehicle. The ball screw actuator is configured to form a second load path parallel to the first load path between the vehicle body and the unsprung components. The ball screw actuator includes a shaft, a housing, a motor, a ball nut, and a ball spline. The motor is coupled to the housing and includes a stator and a rotor. The motor applies torque to the ball nut to transmit force of the second load path between the housing and the shaft. The ball spline applies torque to the shaft to prevent it from rotating relative to the housing. The housing, stator, and ball spline are interconnected to form a stationary assembly. The rotor and ball nut are interconnected to form a rotating assembly, which is rotatably supported by a thrust bearing and axially fixed to the stationary assembly.

[0024] A thrust bearing can be coupled to a ball nut and a housing. The rotating assembly can be further rotatably supported by the housing, while another bearing is coupled to the housing and the rotor. This other bearing can be spaced apart from and axially positioned above the thrust bearing. The stator can be axially positioned between the thrust bearing and the other bearing. The spring can be either a coil spring or an air spring. The housing can be an inner housing, and the suspension system also includes an outer housing to which the inner housing is coupled and which surrounds the inner housing, the motor, and the ball nut. The inner housing can be coupled to the outer housing via a first tubular isolator positioned above the stator. The inner housing can be coupled to the outer housing via a second tubular isolator positioned below at least a portion of the stator.

[0025] A ball screw actuator includes a housing, a motor, a shaft, a ball nut, and ball splines. The motor is located within the housing. The housing surrounds the motor and includes cooling channels for receiving fluid used to cool the motor. The shaft moves axially within the housing. The motor applies torque to the ball nut to transmit axial force between the housing and the shaft. The ball splines transmit torque between the housing and the shaft to prevent rotation between them. The housing is coupled to the ball nut to allow rotation between them and prevent axial movement between them. The housing is coupled to the ball splines to prevent both rotation and axial movement between them.

[0026] The housing can be connected to the ball nut via a thrust bearing. The motor rotor can be rotatably connected to the housing via another bearing positioned above the thrust bearing. The housing can extend from above the motor to below the ball nut. The ball spline can be positioned below the ball nut and connected to the lower end of the housing. Attached Figure Description

[0027] The following detailed description is best understood by referring to the accompanying drawings while reading this disclosure. It should be emphasized that, by convention, the various features in the drawings are not proportional. Instead, for clarity, the dimensions of the various features have been arbitrarily enlarged or reduced.

[0028] Figure 1 This is a schematic diagram of a vehicle according to an exemplary embodiment.

[0029] Figure 2 for Figure 1 Another schematic diagram of the vehicle.

[0030] Figure 3 for Figure 1 A schematic cross-sectional view of the vehicle's suspension system.

[0031] Figure 4 for Figure 3 A schematic cross-sectional view of a variant of the suspension system.

[0032] Figure 5 This is a schematic diagram of the controller.

[0033] Figure 6A For use with Figure 1 An elevation view of a suspension system used in vehicles.

[0034] Figure 6B for Figure 6A A cross-sectional view of the suspension system.

[0035] Figure 6C is Figure 6A A cross-sectional view of the actuator of the suspension system.

[0036] Figure 6D is Figure 6A A cross-sectional view of the rotating structure of the suspension system.

[0037] Figure 6E is Figure 6A A cross-sectional view of the fixed structure of the suspension system.

[0038] Figure 6F For including Figure 6A A schematic diagram of a vehicle with four suspension systems.

[0039] Figure 7A For use Figure 1 A schematic cross-sectional view of another suspension system in the vehicle.

[0040] Figure 7B for Figure 7A A schematic cross-sectional view of a suspension system with crosshairs indicating the pressurization chambers.

[0041] Figure 7C For including Figure 7A A schematic diagram of the vehicle's four suspension systems and pressurized air source.

[0042] Figure 8A For use Figure 1 A schematic cross-sectional view of another suspension system in the vehicle.

[0043] Figure 8B for Figure 8A A schematic cross-sectional view of a suspension system with pressure chambers indicated by crosshairs.

[0044] Figure 9 for Figure 8A A schematic cross-sectional view of a variant of a suspension system with pressure chambers indicated by crosshairs.

[0045] Figure 10 for Figure 8A A schematic cross-sectional view of another variant of the suspension system with pressure chambers indicated by crosshairs.

[0046] Figure 11A For use Figure 1 A schematic cross-sectional view of another suspension system in the vehicle.

[0047] Figure 11B for Figure 11A A schematic cross-sectional view of a suspension system with pressure chambers indicated by crosshairs. Detailed Implementation

[0048] This document discloses various embodiments of vehicle 100 and its functional subsystems (including suspension system 160). More specifically, suspension system 160 is an active suspension system configured to control the generally vertical movement of the wheels using linear actuators that can apply upward and downward forces to introduce energy into and absorb energy from the wheels.

[0049] See Figure 1 Vehicle 100 typically includes a body 102 and a drive system 120 connected to the body 102. The body 102 may, for example, include or define a passenger compartment for transporting passengers. The drive system 120 is configured to move the vehicle 100, including the passenger compartment. The drive system 120 includes various functional subsystems, including a propulsion system 130 (i.e., for propulsing the vehicle 100), a braking system 140 (i.e., for decelerating the vehicle 100), a steering system 150 (i.e., for steering the vehicle 100 in different directions), a suspension system 160 (i.e., for supporting the vehicle 100), a sensing system 170 (i.e., for sensing various aspects of the vehicle 100, including the various subsystems and the external environment), and a control system 180 (i.e., for controlling the various other subsystems individually or in a coordinated manner). The drive system 120 may be an autonomous drive system that operates the various functional subsystems to move the vehicle 100 to a user-selected location without further input from the user.

[0050] See Figure 2 The vehicle 100 includes wheels 104 (e.g., four), which are coupled to and support a body 102 (e.g., on a public road). The wheels 104 may be coupled to the body 102, for example, via a propulsion system 130, a steering system 150, and a suspension system 160. The wheels 104 may include tires (not shown or marked separately), such that each wheel 104 can be considered a sub-assembly of a rim and a tire.

[0051] The propulsion system 130 typically includes one or more motors 232, one or more gearboxes 234, and a drive shaft 236 (e.g., a half-shaft) operably connected to each wheel 104 in one of the gearboxes 234. Broadly speaking, the motors 232 provide torque to the gearboxes 234, which alter the output torque (e.g., increase) and output speed (e.g., decrease) of the motors 232, and the drive shafts 236 transmit torque from the gearboxes 234 to the wheels 104. The motors 232 can provide positive torque to propel the vehicle 100 forward and decelerate it backward, and can also provide negative torque to propel the vehicle 100 backward and decelerate it forward. When receiving torque from the wheels 104, the motors 232 can also function as generators and for charging the vehicle 100's battery (not shown) or other energy storage systems. As shown in the figure, the propulsion system 130 may include a front propulsion system 130f and a rear propulsion system 130r. Each of the front propulsion system 130f and the rear propulsion system 130r includes two motors 232 coupled to a single gearbox 234 and associated with a drive shaft 236 and a wheel 104 coupled thereto. Variations of the propulsion system 130 are contemplated, which may include different numbers of driven wheels 104 (e.g., only the front or rear wheels are driven), different numbers of motors 232 associated with the wheels 104 (e.g., one motor 232 associated with two wheels 104), and different numbers of gearboxes 234 associated with the wheels 104 (e.g., one gearbox 234 dedicated to each wheel 104).

[0052] The braking system 140 typically provides deceleration torque through friction to slow down the vehicle 100 when moving forward and / or backward.

[0053] Steering system 150 typically includes one or more steering actuators 252 and a steering linkage mechanism 254 operatively coupled to one of the steering actuators 252 for each wheel 104. More broadly, steering system 150 controls the pivoting position of the wheel 104 about a generally vertical axis. The steering actuator 252 moves the steering linkage mechanism 254 relative to the vehicle body 102 in inward and outward directions, thereby pivoting the wheel 104 about a vertical axis. As shown, steering system 150 may include a front steering system 150f and a rear steering system 150r, each including a steering actuator 252 associated with two steering linkage mechanisms 254 and the wheels 104 coupled thereto. Variations of steering system 150 are contemplated that may include different numbers of steering actuators 104 associated with the wheels 252 (e.g., one steering actuator 104 for each wheel 252).

[0054] Suspension system 160 typically includes actuators 262 (e.g., suspension actuators) and axles 264 (e.g., suspension axles) associated with each wheel 104. The mechanical components of suspension system 160, including actuators 262, axles 264, and other components discussed below, can be considered as assemblies (e.g., suspension assemblies). More broadly, suspension system 160 controls the vertical movement of wheels 104 relative to vehicle body 102, for example, to ensure contact between wheels 104 and the road surface and to limit the effects of road conditions on undesired movement of vehicle body 102. Suspension system 160 is an active suspension system in which actuators 262 transfer energy to and absorb energy from wheels 104 through upward and downward movement relative to vehicle body 102. As shown in the figure, the suspension system 160 may include a left front suspension system 160fl, a right front suspension system 160fr, a left rear suspension system 160rl, and a right rear suspension system 160rr, each of which includes an actuator 262 and a shaft 264. Further details of the suspension system 160 are discussed in more detail below.

[0055] The sensing system 170 includes sensors for observing the external conditions of the vehicle 100 (e.g., the position of roads and other objects) and the condition of the vehicle 100 (e.g., the acceleration and condition of various subsystems and their components). The sensing system 170 may include various types of sensors, including dedicated sensors and / or functional components of various subsystems (e.g., actuators may be used as sensors).

[0056] The control system 180 includes communication systems and components (i.e., for receiving sensor signals and sending control signals) and processing components (i.e., for processing sensor signals and determining control operations), such as controllers. The control system 180 may include various control subsystems, for example, associated with (or as part of) one or more of the various other subsystems described herein (e.g., propulsion system 130, braking system 140, etc.).

[0057] See Figure 5 The diagram illustrates the hardware configuration of a controller 581 for control system 180, which can be used to implement the apparatus and systems described herein (e.g., to detect their effects and / or predict their expected effects, and to control motion mechanisms). For example, controller 581 can output commands, such as voltage values, to various subsystems of drive system 120 in response to signals received from sensors of sensing system 170.

[0058] Controller 581 may include processor 581a, memory 581b, storage device 581c, one or more input devices 581d, and one or more output devices 581e. Controller 581 may include bus 581f or similar means to interconnect components for communication. Processor 581a is operable to execute computer program instructions and perform operations described by the computer program instructions. As an example, processor 581a may be a conventional device such as a central processing unit. Memory 581b may be a volatile, high-speed, short-term information storage device such as a random access memory module. Storage device 581c may be a non-volatile information storage device such as a hard disk or solid-state drive. Input device 640 may include any type of human-machine interface, such as buttons, switches, keyboards, mice, touchscreen input devices, gesture input devices, audio input devices, and sensors of sensing system 170. The output device 581e may include any type of device operable to provide the user with indications about the operating status, such as a display screen or audio output, or any other functional output or control, such as the propulsion system 130, braking system 140, steering system 150 and / or suspension system 160.

[0059] See Figure 3 The suspension system 160 is configured as a strut assembly, the upper end of which is connected to the vehicle body 102, and the lower end of which is connected to the unsprung component 306 supporting the wheel 104. The unsprung component 306 moves vertically relative to the vehicle body 102 and may be, for example, a steering joint or a suspension control arm.

[0060] Suspension system 160 typically includes actuator 262 and shaft 264, and spring 366, which work together to transmit forces axially between unsprung component 306 and body 102 via two load paths (e.g., dual paths). Spring 366 may be a coil spring (e.g., a metal coil spring), or it may be another suitable type of spring used in this suspension system 160 (e.g., an air spring, a spring formed of another solid material, such as a composite material). The first load path is formed by spring 366 and carries the preload of gravity on vehicle 100 (i.e., a load independent of any dynamic load due to gravity) and a portion of the dynamic load between body 102 and unsprung component 306. The second load path is formed by actuator 262 and shaft 264, which carries another portion of the dynamic load between body and unsprung component 306 and provides the primary damping function of suspension system 160 compared to the first load path.

[0061] The suspension system 160 also includes a housing 368, a top mount 370, and a bottom mount 372, as well as vibration isolators (e.g., shock absorbers, bushings, etc.) and one or more load sensors 380. The housing 368 is coupled to both the actuator 262 and the spring 366 to transmit a second load path and a first load path to the top mount 370 (i.e., to the vehicle body 102) and the bottom mount 372 (i.e., to the unsprung component 306), respectively, or from the top mount 370 and the bottom mount 372, respectively. The actuator 262 is typically housed within the housing 368 and coupled to the housing via an upper internal isolator 374 (e.g., a first vibration isolator or an upper actuator isolator) and a lower internal isolator 376 (e.g., a second vibration isolator or a lower actuator isolator), which transmit axial, radial, and torsional forces between them. Spring 366 is attached to the lower end of housing 368 and includes an external isolator 378 (e.g., a third vibration isolator, a lower isolator, or a helical spring isolator) that transmits axial force between them.

[0062] Because the preload (i.e., vehicle weight) is applied to the suspension system 160 via the first load path through the spring 366 and around the actuator 262, the second load path is nominal (e.g., close to zero) under static or near-static conditions, thus allowing the stiffness of the upper internal isolator 374 and the lower internal isolator 376 to be significantly less than the stiffness of the outer isolator 378. For example, the upper internal isolator 374 and the lower internal isolator 376 can be configured to have spring stiffness curves, damping coefficients, and other characteristics independent of the corresponding characteristics of the outer isolator 378 by not transmitting the preload. Furthermore, the upper internal isolator 374 and the lower internal isolator 376 can have such characteristics that differ from each other.

[0063] The top mounting bracket 370 is connected to the upper end of the housing 368 and the body 102 to transmit force to the body 102 (i.e., the first load path and the second load path). The bottom mounting bracket 372 is independently connected to the lower end of the spring 366 and the shaft 264 to transmit force to the unsprung component 306 (i.e., the first load path and the second load path).

[0064] Actuator 262 is positioned above spring 366, thereby being supported above it by body 102 (e.g., suspended). This orientation offers several advantages compared to mounting actuator 262 below spring 366 (i.e., compared to supporting actuator 262 from below with unsprung component 306). For example, by being supported by body 102, actuator 262 is not an unsprung mass, and actuator 262 is also mounted closer to body 102 for connecting power, data, and / or cooling lines in a location closer to body 102 and less susceptible to damage (e.g., from debris).

[0065] Actuator 262 is a ball screw actuator that converts the rotational motion and torque from an electric motor (unlabeled) into linear motion and force on shaft 264, respectively. The torque output of the motor is typically related to the linear force output of actuator 262. Specific details regarding the ball screw aspect of actuator 262 are not discussed in this document.

[0066] Actuator 262 is used to transfer energy to wheel 104 to cause wheel 104 to move upward and downward relative to vehicle body 102. Actuator 262 also acts as an energy absorber from wheel 104 (e.g., as a shock absorber) as wheel 104 moves upward and downward relative to vehicle body 102 due to external forces (i.e., the exterior of actuator 262). The upward movement is caused by an upward force exerted on wheel 104 by the road as vehicle 100 moves along the road. The downward movement is typically caused by gravity acting on wheel 104 and / or a spring 366 exerting a downward force on wheel 104.

[0067] Actuator 262 includes a body 262a and a shaft 264 that is axially movable relative to the body 262a. The body 262a may, for example, form or contain a motor (e.g., form a stator and contain a rotor of the motor) at its upper end and form or contain a rotating nut (e.g., a ball nut) at its lower end. When the nut is rotated by the motor, the nut engages with the shaft 264 (via the circulating balls) and causes the shaft 264 to translate axially relative to the body 262a.

[0068] The main body 262a is mounted within the housing 368 together with the upper internal isolator 374 and the lower internal isolator 376 to transmit axial, radial, and rotational forces between them. The upper internal isolator 374 and the lower internal isolator 376 are configured to suppress noise and vibration of the actuator 262 and prevent it (e.g., due to the operation of the motor and the movement of the balls in the nut of the ball screw mechanism) from reaching the body 102, while also allowing the actuator 262 to move axially and radially relative to the housing 368.

[0069] Each of the upper internal isolator 374 and the lower internal isolator 376 is axially coupled directly or indirectly to the inner and outer surfaces of the housing 368 and the body 262a of the actuator 262, respectively, to transmit axial force (i.e., a second load path) between them. The upper internal isolator 374 and the lower internal isolator 376 are also arranged radially (e.g., concentrically) between the housing 368 and the body 262a to transmit radial force (e.g., due to bending moment) between them. The upper internal isolator 374 and the lower internal isolator 376 may also be rotatably coupled directly or indirectly to the housing 368 and the body 262a of the actuator to transmit rotational torque between them. The upper internal isolator 374 and the lower internal isolator 376 may be made, for example, of a suitable material (e.g., rubber or polymer) having suitable properties (e.g., damping characteristics and elastic modulus) due to their material properties and / or structural characteristics.

[0070] In the axial direction, the upper internal isolator 374 and the lower internal isolator 376 are configured to gradually flex axially over the entire travel (e.g., travel distance) as the axial force increases to the maximum design load. The maximum design load can be a peak (or near-peak) load expected during the operation of the vehicle 100 (e.g., extreme conditions during normal driving, after which the suspension system 160 can be expected to continue operating). The maximum design load can be, for example, 10 kN, while the maximum design deflection (e.g., maximum travel) can be 10 mm. The restoring spring force of the upper internal isolator 374 and the lower internal isolator 376 is preferably substantially linear over the entire travel; for example, the upper internal isolator 374 and the lower internal isolator 376 together provide a substantially constant axial spring stiffness (e.g., + / - 25%, + / - ~ 15%, + / - 10% or less) over the entire travel, such as about 1 kN / mm. A substantially constant spring stiffness may be particularly advantageous for the control strategy of the suspension system 160 (e.g., a simplified control strategy).

[0071] Alternatively, the restoring spring force can be substantially linear over most of the travel. The spring stiffness can be substantially constant in the first portion of the travel (e.g., between approximately 75% and 90% of the travel) and can gradually increase in the second portion of the travel (e.g., between 10% and 25% of the remaining travel) to significantly improve the spring stiffness. This significantly higher spring stiffness in the second portion of the travel prevents violent engagement between the two normally rigid components of the suspension system 160 under higher loads (e.g., close to 10 kN).

[0072] In the radial direction, the upper internal isolator 374 and the lower internal isolator 376 are configured to prevent the actuator 262 (e.g., body 262a) from radially engaging with the housing 368. The stiffness of the upper internal isolator and the lower internal isolator 376 can be significantly less in the radial direction than in the radial direction. Otherwise, when a bending moment is applied to the suspension system 160, radial engagement could occur between the actuator 262 and the housing 368. Such a bending moment could, for example, be caused by the deflection of the unsprung component 306 relative to the vehicle body 102. For this purpose, the upper internal isolator 374 and the lower internal isolator 376 are respectively coupled to the body 262a at axially spaced locations, which reduces the radial force component of the bending moment experienced by each of the upper internal isolator 374 and the lower internal isolator 376 when the actuator 262 pivots about the other of the upper internal isolator 374 and the lower internal isolator 376. A larger axial spacing allows the upper internal isolator 374 and the lower internal isolator 376 to have lower stiffness in the radial direction (i.e., lower restoring spring stiffness) and / or the housing 368 to be closer to (e.g., smaller) the body 262a.

[0073] The top mount 370 allows the suspension system 160 to pivot relative to the vehicle body 102 with minimal resistance (e.g., freely or with minimal resistance) to prevent the movement of the unsprung component 306 from exerting a high bending moment on the actuator 262. More specifically, the top mount 370 allows the suspension system 160 to pivot with minimal resistance (e.g., freely or with low resistance) in two rotational degrees of freedom (e.g., free or unrestricted degrees of freedom) about an axis perpendicular to the longitudinal axis 264. By providing very little (e.g., low) resistance to pivoting in two unrestricted degrees of freedom, the connection between the suspension system 160 and the vehicle body 102 contributes little to the bending moment that would otherwise make the suspension system 160 operational. As shown, the top mount 370 may be a Cadenza joint. Alternatively, the top mount 370 may be a ball joint with interference features (e.g., protrusions in a groove) or an isolator. Because of these two degrees of freedom, the suspension system 160 can pivot relative to the vehicle body 102 in a generally conical region, the apex of which is typically located at the top mount 370.

[0074] The top mount 370 can also restrict (e.g., prevent or have high resistance) pivoting about the longitudinal axis (from top to bottom as shown) in the third rotational degree of freedom (e.g., a restricted degree of freedom). By providing high resistance (e.g., preventing motion) in the restricted degree of freedom, the suspension system is prevented from rotating when the actuator 262 is operated (e.g., when the motor rotates).

[0075] like Figure 4As illustrated, the suspension system 160 may additionally include a torsion isolator 482 (e.g., disposed between the housing 368 and the top mounting bracket 370) that suppresses rotational loads, such as those caused by the rotation of the motor of actuator 262, which cannot be otherwise suppressed by other isolators (discussed in further detail below).

[0076] As described above, the outer isolator 378 is axially arranged between the spring 366 and the housing 368 to transmit the axial force of the first load path between them. The preload (i.e., due to the gravity acting on the vehicle) is transmitted through the outer isolator, so the outer isolator is configured to be significantly more rigid in the axial direction than the upper inner isolator 374 and the lower inner isolator 376 (e.g., with a higher restoring spring stiffness).

[0077] The suspension system 160 may additionally include one or more load sensors 380 configured to measure the axial load from the suspension system 160 to the vehicle body 102. One or more load sensors 380 may be axially arranged, for example, between the top mount 370 and the housing 368. The load sensors 380 may also be considered part of the sensing system 170 and communicate with the control system 180.

[0078] The control system 180 or its suspension control subsystem controls the actuator 262 to achieve the desired force transmission between the wheel 104 and the vehicle body 102. As described above, the actuator 262 is configured to absorb external energy acting on the wheel 104, thereby acting as a shock absorber when the wheel 104 moves vertically relative to the vehicle body 102. Absorption refers to obtaining energy from the suspension system 160, for example, by converting mechanical energy and storing it as electrical energy (e.g., using the motor of the actuator 262 as an electric generator). The actuator 262 is also configured to input energy to the wheel 104, thereby causing the wheel 104 to move vertically relative to the vehicle body 102.

[0079] When actuator 262 is operated to achieve the desired axial force transmission between vehicle body 102 and wheel 104, control system 180 can adjust the input of actuator 262 to accommodate axial compliance introduced by upper internal isolator 374, lower internal isolator 376, and to a lesser extent by external isolator 378. For example, the compression state of upper internal isolator 374, lower internal isolator 376, and external isolator 378 can be described using load sensor 380 (e.g., based on known or tested spring stiffness). Based on different measurements received from load sensor 380 at different times, the input of actuator 262 (e.g., motor speed and / or torque) can differ, even though the same output and response (i.e., axial force and / or displacement over a given time) is sought from actuator 262. For example, assuming the isolator's cooperating spring stiffness is 1 kN / mm and the preload is 5 kN (i.e., the first load path), then a 5 kN axial force measurement represents a 0 kN axial load (i.e., through the second load path) and 0 mm isolator deflection. Therefore, to achieve the desired output force of 8 kN within a given time range, a compliance of 3 mm must be demonstrated by, for example, initially rotating the motor at a relatively high speed. A 7 kN axial force measurement represents a 2 kN axial load and 2 mm isolator deflection. Therefore, to achieve the same desired output force of 8 kN within the same given time range, a compliance of 1 mm must be demonstrated by, for example, initially rotating the motor at a relatively low speed.

[0080] The suspension system 160 may additionally include a position sensor 384 (e.g., a displacement sensor) that measures the deflection of various isolators (e.g., by measuring the change in position of the body 262a of actuator 262 relative to housing 368). This displacement information may be used alone and / or together with force information to determine the input to actuator 262 (e.g., motor speed and / or torque). For example, the material properties of various isolators may change with temperature and / or aging, which can be illustrated by measuring the displacement of the isolators using position sensor 384. For example, a measured displacement that is not correlated with the expected force value can be illustrated by the input to actuator 262 to achieve the desired axial force or displacement output (e.g., using the example above, a measured 2 mm displacement is not correlated with a measured 6 kN force).

[0081] See Figures 6A to 6B The 660 suspension system can be used as Figure 1Any of the suspension systems 160fl, 160fr, 160rl, and 160rr shown. Suspension system 660 is coupled to the vehicle body 102 at its upper end and to the unsprung component 306 at its lower end. Suspension system 660 is configured similarly to the previously described suspension system 160. Where common reference numerals are used to identify components, features, or other elements of suspension system 660 between suspension system 660 and suspension system 160, further details regarding such components, features, or other elements can be found in the discussion of suspension system 160. Suspension system 660 and its variants described below (e.g., suspension systems 760, 860, 960, 1060, and 1160) may also be referred to as suspension components or devices, or strut systems, components, or devices.

[0082] The suspension system 660 typically includes an actuator 662, a shaft 664, a spring 366, and an outer housing 668, which can respectively serve as the actuator 262, shaft 264, spring 366, and housing 368 in the suspension system 160. The suspension system also includes a top mount 370 and a bottom mount 372.

[0083] As discussed above with reference to suspension system 160, suspension system 660 is configured to transmit axial forces from unsprung component 306 to vehicle body 102 via two parallel load paths. The first load path is formed by spring 366 and outer housing 668, which carries a preload (e.g., a portion of the weight of vehicle 100) and a portion of the dynamic load between vehicle body 102 and unsprung component 306. The second load path is formed by actuator 662, axle 664, and outer housing 668, which carries another portion of the dynamic load between vehicle body 102 and unsprung component 306, including providing primary damping against road disturbances.

[0084] Referring also to Figure 6C, actuator 662 is a linear actuator configured as a ball screw actuator or mechanism. Actuator 662 includes a motor 662a having a rotor 662b and a stator 662c, a ball nut 662d (e.g., a ball screw nut), a ball spline 662e (e.g., a ball spline nut), and an inner housing 662f having a lower inner housing portion 662g and an upper inner housing portion 662h. Shaft 664 extends through actuator 662 and can be considered part of actuator 662. Broadly speaking, motor 662a applies torque to ball nut 662d relative to outer housing 668 to control axial movement of shaft 664 relative to outer housing 668, thereby controlling axial movement of unsprung component 306 relative to body 102. The ball spline 662e prevents the shaft 664 from rotating relative to the outer housing 668, thereby preventing torque from being transmitted from the motor 662a via the shaft 664 to the unsprung component 306 (e.g., suspension arm) or other components (e.g., steering linkage 254). The actuator 662 and other actuators described herein can be configured as other types of linear actuators, such as rack and pinion systems, linear motors, or other suitable linear actuators. The inner housing 662f and outer housing 668 can also be referred to as rigid housings. The lower inner housing portion 662g and the upper inner housing portion 662h can also be referred to as the lower housing structure and the upper housing structure, respectively.

[0085] Referring also to Figure 6D, the rotor 662b and the ball nut 662d rotate together. The rotor 662b and the ball nut 662d can be considered to together form the rotating structure 662' of the actuator 662. The ball nut 662d and the rotor 662b can be connected to each other at their axial ends. For example, the ball nut 662d and the rotor 662b can be connected to each other by a threaded fastener (not shown) extending axially through a radially extending flange of the ball nut 662d into the axial end of the rotor 662b, such that the torque generated by the motor 662a is transmitted to the ball nut 662d. The rotor 662b and the ball nut 662d can be connected to each other to transmit torque between them, for example, in a male-to-female interference fit. The rotor 662b may, for example, include a magnet 662b', which is mounted on the radially outer surface of a spindle 662b' configured as a hollow shaft. The rotor 662b is hollow so that it can rotate independently of the shaft 664 about which the shaft 664 translates axially. The rotating structure 662' may also be referred to as a rotating assembly.

[0086] Referring also to Figure 6E, the stator 662c, ball spline 662e, and inner housing 662f are fixedly connected to each other to prevent rotation and axial movement between them. The stator 662c, ball spline 662e, and inner housing 662f can be considered to collectively form the fixed structure 662' of actuator 662, with the rotating structure 662' rotating relative to the fixed structure 662'. The lower inner housing portion 662g and the upper inner housing portion 662h of inner housing 662f are rigid annular structures connected to each other at their axial ends to prevent relative movement between them. For example, the lower inner housing portion 662g and the upper inner housing portion 662h can be connected to each other by threaded fasteners (not shown) extending axially therein or by other suitable means (e.g., male-to-female interference fit). Alternatively, the inner housing 66 2f can be an integral structure forming the inner housing, or it can be formed by additional structures forming the inner housing 662f. The stator 662c is coupled inside the inner housing 662f to prevent relative movement therebetween, for example, coupled to (e.g., in contact with) the inner surface of the upper inner housing portion 662h. As shown, the upper inner housing portion 662h may include a cooling channel 662f' (e.g., a cooling passage) through which fluid can flow to cool the motor 662a (e.g., the stator 662c). The upper inner housing portion 662h may also be referred to as a stator housing or a cooling jacket. The fixing structure 662" may also be referred to as a fixing assembly.

[0087] The ball spline 662e is coupled to the inner housing 662f to prevent relative rotation and axial movement therebetween, for example, to the lower inner housing portion 662g. As shown, the ball spline 662e and the lower inner housing portion 662g each include radially extending flanges that overlap each other radially. The flanges of the ball spline 662e and the lower inner housing portion 662g are coupled to each other, for example, by threaded fasteners (not shown) extending axially therein and preventing axial and rotational movement between them. The ball spline 662e and the lower inner housing portion 662g may be coupled to each other in other ways to prevent axial and / or rotational movement relative to each other, such as by male-to-female interference fit to prevent relative rotation, and by retaining rings or nuts to prevent axial movement.

[0088] The rotating structure 662' (i.e., formed by the rotor 662b and the ball nut 662d) is configured to rotate relative to the fixed structure 662 (i.e., formed by the stator 662c, the ball spline 662e, the lower inner housing portion 662g, and the upper inner housing portion 662h), thereby applying an axial force (i.e., the force of the second load path) between the fixed structure and the shaft 664. The axial force applied to the shaft 664 by the rotating structure 662' will cause, limit, prevent, or otherwise control the axial movement of the shaft 664 relative to the actuator 662 to control the force transmission in the second load path between the unsprung component 306 and the body 102.

[0089] More specifically, motor 662a receives current, which generates torque between rotor 662b and stator 662c. When torque is applied to rotor 662b, torque is applied to ball nut 662d, and axial force is applied from ball nut 662d to shaft 664. More specifically, the axial force is applied between ball nut 662d and shaft 664 via a first set of recirculating balls (not shown; such as ball bearings), as is known in the field of ball screw nuts. The recirculating balls engage with an outer helical groove 664a in the outer surface of shaft 664 and a corresponding inner helical groove 662d' in the inner surface of ball nut 662d, thereby applying an axial force between ball nut 662d and shaft 664 when torque is applied to ball nut 662d. By controlling the torque applied to the ball nut 662d by the motor 662a (e.g., by controlling the electrical power applied to the motor 662a), the axial force applied to the shaft 664 by the actuator 662 can be controlled to cause, limit, prevent, or otherwise control the axial movement of the shaft 664 relative to the actuator 662. The actuator 662 can thus control the transmission of force between the unsprung component 306 and the vehicle body 102, for example, dissipating energy from road disturbances and / or maintaining contact between the wheel connected to the unsprung component 306 and the road surface beneath it. For example, the actuator 662 can be used as a shock absorber. The ball nut 662d can also be referred to as a ball screw nut.

[0090] The fixing structure 662” is also configured to prevent the shaft 664 from rotating relative to it. In addition to applying axial force to the shaft 664, the torque applied to the ball nut 662d by the motor 662a is also applied to the shaft 664 due to the inclination of the helical groove 664a of the shaft 664 and the helical groove 662d' of the ball nut 662d. The fixing structure 662”, in particular, the ball spline 662e resists this torque applied to the shaft 664 by the motor 662a. Therefore, torque is not transmitted from the actuator 662 to the unsprung component 306, which would otherwise cause undesirable lateral movement of the unsprung component 306 (e.g., if the control arm tends to pivot vertically relative to the vehicle body 102). Such lateral movement can, for example, cause wear on the pivot joints and / or bushings through which the unsprung component 306 is mounted to the vehicle body 102 and / or can cause undesirable forces in the steering system 150.

[0091] The ball spline 662e engages with the shaft 664 to prevent this torque from causing the shaft 664 to rotate relative to the actuator 662. More specifically, a second set of circulating balls (not shown; such as ball bearings) engages an outer axial groove 664b in the outer surface of the shaft 664 and an inner axial groove 662e' of the ball spline 662e. For example, the shaft 664 may include two outer axial grooves 664b spaced 180 degrees apart from each other, while the ball spline 662e includes two inner axial grooves 662e' spaced 180 degrees apart from each other and corresponding thereto. The tangential force generated by the torque applied to the shaft 664 by the ball nut 662d is transmitted via a second set of circulating balls through the ball spline 662e, thereby preventing the shaft 664 from rotating relative to the fixed structure 662” of the actuator 662. Alternatively, the shaft 664 may include a keyway, a sliding key, or a rolling key tangentially ridden and carried therein to transmit torque between the shaft 664 and the fixed structure 662” to prevent rotation therebetween.

[0092] The rotating structure 662' (i.e., the assembly of rotor 662b and ball nut 662d) is rotatably and axially supported by the fixed structure 662" (i.e., via the assembly of stator 662c, ball spline 662e, lower inner housing portion 662g, and upper inner housing portion 662h). ​​For example, as shown, the rotating structure 662' is rotatably connected to the fixed structure 662 via a lower bearing assembly 676 and an upper bearing assembly 678. Each of the lower bearing assembly 676 and the upper bearing assembly 678 prevents radial movement between the rotating structure 662' and the stationary structure 662"". Each of the lower bearing assembly 676 and the upper bearing assembly 678 may be a ball, roller, or needle roller bearing assembly or the like (e.g., ball, roller, needle, etc.; not shown) having an inner and outer race with roller elements rotating relative to each other. One or both of the lower bearing assembly 676 and the upper bearing assembly 678 may be additionally configured to prevent axial movement between the rotating structure 662' and the stationary structure 662" for example, configured as a thrust bearing. For example, as shown, the lower bearing assembly 676 may be a thrust bearing.

[0093] The lower bearing assembly 676 can be radially positioned between the ball nut 662d and the lower inner housing portion 662g. The inner race of the lower bearing assembly 676 is rotatably and axially fixed to the ball nut 662d, thereby rotating with it, and can be considered as part of the rotating structure 662'. For example, the inner race engages with the radially outer surface of the ball nut 662d, thereby being rotatably and radially coupled thereto. The inner race is additionally axially held between the upper flange of the ball nut 662d, which extends radially outward from its radially outer surface, and a nut 680 or other fastener (e.g., a retaining ring or locking ring) that engages with the radially outer surface at the intermediate height of the ball nut 662d.

[0094] The outer race of the lower bearing assembly 676 is rotatably and axially fixed to the inner housing 662f and can be considered as part of the fixed structure 662". For example, the outer race engages the radially inner surface of the lower inner housing portion 662g, thereby being rotatably and radially connected to the radially inner surface of the lower inner housing portion 662g. The outer race is additionally axially held between a flange of the lower inner housing 662f extending radially inward from the radially inner surface and a retaining ring 682 or other fastener (e.g., an externally threaded nut) engaging the radially inner surface of the lower inner housing portion 662g.

[0095] The upper bearing assembly 678 can be radially positioned between the rotor 662b and the inner housing 662f. The inner race of the upper bearing assembly 678 engages (e.g., press-fits to) the radially outer surface of the rotor spindle 662b' to prevent radial and rotational movement between them. The inner race can be considered part of the rotating structure 662'. The outer race of the upper bearing assembly 678 engages (e.g., press-fits to) the radially inner surface of the upper inner housing portion 662h to prevent radial and rotational movement between them, while allowing the inner race to rotate relative to it, but not radially. The outer race can be considered part of the stationary structure 662''.

[0096] The lower bearing assembly 676 and the upper bearing assembly 678 are axially spaced to resist any bending moment between the rotating structure 662' and the stationary structure 662" of the actuator 662. For example, the lower bearing assembly 676 may be positioned below the motor (e.g., below the magnet 662b' of the rotor 662b and stator 662c) and resists radial loads between the rotating structure 662' and the stationary structure 662" such as between the ball nut 662d and the lower inner housing portion 662g, which may be due to bending moment. The upper bearing assembly 678 may be positioned above the motor (e.g., above the magnet 662b' of the rotor 662b and stator 662c) and resists radial loads between the rotor 662b (e.g., its spindle 662b') and the upper inner housing portion 662h, which may be due to bending moment.

[0097] The ball nut 662d and ball spline 662e are axially spaced to resist any bending moment between the shaft 664 and the actuator 662. More specifically, since the rotating structure 662' is axially fixed to the fixed structure 662" (e.g., via a lower bearing assembly 676 configured as a thrust bearing), the ball nut 662d and ball spline 662e are axially fixed relative to each other, with the ball nut 662d positioned above the ball spline 662e. When a bending moment is applied between the shaft 664 and the actuator 662, the ball nut 662d and ball spline 662e exert radial forces on the shaft 664 at different axial positions on the shaft 664 to resist the bending moment applied thereto.

[0098] As described above, the outer housing 668 transmits force between a first load path (i.e., via the spring 366) and a second load path (i.e., via the actuator 662 and the shaft 664) between the unsprung component 306 and the body 102. As shown, the outer housing 668 can be configured as a multi-piece assembly. The outer housing 668 includes an upper outer housing 668a, a middle outer housing 668b, and a lower outer housing 668c, which are generally annular structures surrounding portions of the actuator 662 and / or the shaft 664.

[0099] The upper outer housing 668a is coupled to the top mounting bracket 370 to transfer load to the top mounting bracket. Various electronic circuits and components (e.g., rotor encoder, position sensor, force sensor; not shown) may be contained in a portion of the internal cavity of the outer housing 668, defined by the upper outer housing 668a. The upper internal isolator 374 may also be coupled to the upper outer housing 668a and the upper internal housing portion 662h (e.g., radially located therebetween).

[0100] The intermediate outer housing 668b is connected to the upper outer housing 668a (e.g., via threaded fasteners) and extends downward from the upper outer housing 668a. The intermediate outer housing 668b defines the main portion of the internal cavity of the outer housing 668, which typically includes the upper inner housing portion 662h and the motor 662a (i.e., rotor 662b and stator 662c). The lower internal isolator 376 may be connected to the intermediate outer housing 668b and the lower inner housing portion 662g (e.g., radially positioned therebetween).

[0101] The lower outer housing 668c is coupled to and extends downward from the intermediate outer housing 668b (e.g., via a male-to-female threaded engagement). The lower outer housing 668c defines a portion of a cavity of the outer housing 668 containing a portion of the lower inner housing portion 662g and a ball nut 662d, either of which may axially project below the bottom end of the lower outer housing 668c. The lower outer housing 668c may also function as a spring seat in which and / or opposite to it receives a spring 366 (e.g., via an isolator between them) for transferring the load of a first load path to it. The lower outer housing 668c may be axially adjustable relative to the intermediate outer housing 668b, for example, via a threaded engagement therebetween, thereby forming an adjustable spring seat.

[0102] As described above and as shown in the figures, actuator 662 is coupled to outer housing 668 via upper internal isolator 374 and lower internal isolator 376, which can be configured to function as previously described to connect between actuator 262 and housing 368 and transmit load. Each of the isolators can be a tubular isolator having an inner rigid ring member and an outer rigid ring member, and an intermediate compliant ring member therebetween. The inner and outer ring members are coupled to the inner housing (e.g., to the lower inner housing portion 662g or the upper inner housing portion 662h) and the outer housing 668, respectively, while the intermediate compliant ring member provides compliance between them. The function of the upper internal isolator 374 and the lower internal isolator 376 is to transmit the axial load of the second load path between the actuator 662 and the outer housing 668, while suppressing vibrations or other disturbances generated by the actuator 662 (e.g., due to motor operation, movement of the circulating balls within the ball nut 662d and ball spline 662e, and other friction) and / or vibrations or other disturbances generated outside the actuator (e.g., road disturbances acting on the unsprung component 306). Additionally, the upper internal isolator 374 and the lower internal isolator 376 are axially spaced to resist bending moments between the actuator 662 and the outer housing 668.

[0103] like Figure 6B As shown, the suspension system 660 may also include various electronic devices, schematically illustrated. These electronic devices are configured to monitor the condition of the suspension system 660 (e.g., forces and displacements), which can be used to control the suspension system 660 and other systems of the vehicle 100. For example, the top mount 370 may include one or more force sensors 671, such as force sensors, that measure the forces transmitted between the housing 668 and the top mount (i.e., the forces of both the first and second load paths). The actuator 662 may include motor electronics 663, which may include various electronic devices (e.g., rotor encoders) for supplying or drawing power from the motor 662 and controlling its operation. The actuator 662 may also include a position sensor 665 for measuring the position of the shaft 664 relative to the actuator 662 (e.g., for determining the length of the suspension system 660 or the height of the vehicle 100 (e.g., between the body 102 and the unsprung components)). See also Figure 6F The electronic devices (i.e., force sensor 671, motor electronics 663, and position sensor 665) can communicate with the control system 180, which can provide control signals to each of the suspension systems 660 (e.g., four suspension systems 660) to control them.

[0104] See Figures 7A to 7BThe suspension system 760 or strut assembly or system can be used as Figure 1 Any one of the suspension systems 160fl, 160fr, 160rl, and 160rr shown. Suspension system 760 is coupled to the vehicle body 102 at its upper end and to the unsprung component 306 at its lower end. Suspension system 760 is configured in some respects to be similar to suspension systems 160 and 660 previously described. Where common reference numerals are used to identify components, features, or other elements of suspension system 760 in relation to suspension systems 160 and 660, discussion of suspension systems 160 and 660 may refer to further details of such components, features, or other elements.

[0105] The suspension system 760 typically includes an actuator 662 and a shaft 664, forming an air spring 766. As discussed in further detail below, the air spring 766 forms a first load path between the unsprung component 306 and the vehicle body 102, which is parallel to a second load path formed by the actuator 662, shaft 664, and upper housing 768. The air spring 766, like the first load path described above, transmits a preload (i.e., the weight of the vehicle 100) between the unsprung component 306 and the vehicle body 102. The actuator 662 and shaft 664 may be configured substantially as previously described to form a second load path between the unsprung component 306 and the vehicle body 102.

[0106] The suspension system 760 includes components such as an actuator 662, a shaft 664, an upper housing 768, a lower housing 770, and a diaphragm 772, as well as a top mount 774 and a bottom mount 778.

[0107] The upper housing 768 is a generally rigid and annular structure that extends downward from the top mounting bracket 774 to surround all or part of the actuator 662. As discussed in further detail below, the upper housing 768 may define an upper chamber 766b of the pressurization chamber 766a of the air spring 766. The upper housing 768 is coupled to the top mounting bracket 774 and extends downward from it to terminate at its bottom end below the ball nut 662d, for example, at least partially overlapping the ball spline 662e. The upper housing 768 may also reduce the diameter of its downward movement from the top mounting bracket 774, for example, by a stepped or gradual reduction in diameter below the stator 662c of the motor 662a. As shown, the upper housing 768 may be a single component, but may be formed as an assembly of multiple components (e.g., similar to an upper outer housing 668a and an intermediate outer housing 668b).

[0108] The upper housing 768 further includes a port 768a through which the air spring 766 receives pressurized gas (e.g., pressurized air) from an air source (not shown) to increase the amount of air in the pressurization chamber 766a to raise the vehicle 100. Air can also be released from the air spring 766 through the port 768a to reduce the amount of air in the pressurization chamber 766a, thereby lowering the vehicle 100.

[0109] The upper housing 768 is connected to the top mounting bracket 774 via an isolator 776, which forms a compliant connection between them while restricting rotational, radial, and axial movement between them. The isolator 776 may be, for example, a tubular isolator having a rigid inner ring member and a rigid outer ring member connected to and spaced by a compliant intermediate ring member. The isolator 776 may be radially positioned and rigidly connected between and to the inner radial portion (e.g., its inner surface) of the upper housing 768 and the outer radial portion (e.g., its downwardly extending annular flange) of the top mounting bracket 774. The isolator 776 transmits the forces of a second load path between the upper housing 768 and the top mounting bracket 774. The isolator 776 also serves to seal the upper housing 768 to the top mounting bracket 774 so as to seal the pressurized chamber 766a with the top mounting bracket 774.

[0110] The top mount 774 is a structure that both seals the pressurization chamber 766a and mechanically connects the suspension system 760 to the vehicle body 102. The top mount 774 may include one or more structures and / or components that are joined together to form the top mount 774. For example, among other components, the top mount 774 may include a lower structure that partially seals the pressurization chamber 766a, and an upper structure that connects the suspension system 760 to the vehicle body 102. The top mount 774 may include additional components and / or functions, such as including a force sensor that measures the force transmission between the suspension system 760 and the vehicle body 102.

[0111] The lower housing 770 is generally a rigid, annular structure that is coupled to and extends upward from the bottom mounting bracket 778, terminating at its upper end. As the body 102 and unsprung component 306, and thus the top mounting bracket 774 and base mounting bracket 778, move toward and away from each other, the upper end of the lower housing 770 changes its axial position relative to the lower end of the upper housing 768. In some locations, the lower housing 770 overlaps the upper housing 768 axially. The upper end of the lower housing 770 has a larger diameter than the lower end of the upper housing 768, such that the upper housing 768 can be received within the lower housing 770. A circumferential clearance 766d is defined between the upper end of the lower housing 770 and the lower end of the upper housing 768. As shown in the figure, the lower housing 770 can be formed as an integral part integrally formed with a portion of the bottom mounting bracket 778, or it can be formed as an assembly of multiple parts (e.g., formed separately from the bottom mounting bracket 778 and connected to the bottom mounting bracket 778).

[0112] The undermount 778 is a structure that serves both to seal the pressurization chamber 766a and to mechanically connect the suspension system 760 to the unsprung component 306. The undermount 778 may include one or more structures and / or components that are coupled to each other to form the undermount 778 as an assembly. For example, among other components, the undermount 778 may include an upper structure that partially seals the pressurization chamber 766a and is connected to a shaft 664, and a lower structure for coupling the suspension system 760 to the unsprung component 306. The shaft 664 is coupled to the undermount 778 to transmit forces along a second load path therebetween.

[0113] A membrane 772 extends radially between the upper end of the lower housing 770 and the lower end of the upper housing 768 to seal the circumferential gap 766d between them. The membrane 772 thereby seals the pressurized chamber 766a. The membrane 772 may be formed of a polymer (e.g., rubber) material or any other suitable flexible material.

[0114] The diaphragm 772 is configured to form the air spring 766 as a leaf spring, as understood in the art. The diaphragm 772 includes an inner diaphragm portion 772a coupled to the lower end of the upper housing 768 and an outer diaphragm portion 772b coupled to the upper end of the lower housing 770. As the vehicle body 102 and the unsprung component 306, and thus the upper housing 768 and the lower housing 770, move toward and away from each other, the inner diaphragm portion 772a and the outer diaphragm portion 772b translate axially relative to each other.

[0115] Actuator 662 is coupled to upper housing 768 to prevent rotation and axial movement therebetween. For example, the actuator may be coupled to upper housing 768 via one or more support structures 780 extending radially between actuator 662 and upper housing 768. One or more support structures 780 may, for example, couple an upper inner housing portion 662h to upper housing 768. Support structures 780 may be positioned above motor 662a (e.g., above stator 662c and / or upper bearing assembly 678). One or more support structures 780 also allow air to flow between upper chamber 766b and lower chamber 766c of pressurization chamber 766a, as discussed further in detail below (e.g., configured as spokes). Thus, the force of the second load path is transmitted between actuator 662 and upper housing 768 via support structures 780. Therefore, the second load path transmits the force between the unsprung component 306 and the body 102 from the bottom mounting bracket 778 to the shaft 664 to the actuator 662 to the upper housing 768 to the isolator 776 and to the top mounting bracket 774.

[0116] As described above, the air spring 766 forms a first load path between the body 102 and the unsprung component 306, while the actuator 662, shaft 664, and upper housing 768 form a second load path parallel to the first load path. Referring first to the first load path, the air spring 766 includes a pressurized chamber 766a, which is a sealed chamber containing pressurized gas or air. The chamber 766a is typically defined by an upper housing 768, a lower housing 770, and a diaphragm 772 sealing therebetween. The chamber 766a may also extend from a top mounting bracket 774 to a bottom mounting bracket 778 and may be defined between them. The force of the first load path is transmitted through pressurized gas acting on the upper and lower ends of the pressurized chamber 766a, which is formed, for example, by the top mounting bracket 774 and the bottom mounting bracket 778, respectively. See also Figure 7B The pressurized chamber 766a is represented by the area shown by the crosshairs. As discussed in further detail below, the actuator 662 and the shaft 664 are contained in the pressurized chamber 766a, whereby they are subjected to air pressure.

[0117] As the body 102 and unsprung component 306 move relative to each other, the volume of the pressurization chamber 766a changes to further compress or depressurize a given amount of air therein, causing the suspension system 760 to apply more or less force between the body 102 and the unsprung component 306, respectively. Furthermore, for a given pressure, air can be selectively added to or removed from the pressurization chamber 766a to increase its volume, thereby changing the length of the suspension system 760 and the distance between the body 102 and the unsprung component 306. As the length of the suspension system changes (e.g., due to the different forces applied between the body 102 and the unsprung component, due to the force applied by the actuator 662 between the bottom mount 778 and the top mount 774, and / or as air is added to or removed from the chamber 666a), the upper housing 768 and the lower housing 770 move axially relative to each other; for example, the upper housing 768 is received within and / or slides within the lower housing 770.

[0118] As described above, the pressurization chamber 766a includes an upper chamber 766b and a lower chamber 766c in fluid communication with each other. The upper chamber 766b is generally defined by an upper housing 768. The lower chamber 766c is generally defined by a lower housing 770 and a diaphragm 772. The actuator 662 and the upper housing 768 generally form a movable assembly relative to the bottom mounting bracket 778 (e.g., a first piston assembly of the air spring 766), which is permitted or allowed to move due to the flexibility of the diaphragm 772. The top mounting bracket 774 generally forms another movable assembly relative to the housing 768 (e.g., a second piston assembly of the air spring 766), which is permitted or allowed to move due to the compliant nature of the isolator 776. The first and second piston assemblies may have approximately equal effective piston areas, typically defined as regions within the midpoint between the inner housing 662g and the lower housing 770 (e.g., the midpoint of the flexible diaphragm) and the midpoint of the intermediate compliance ring of the isolator, respectively. Having approximately equal effective piston areas allows for approximately zero axial static load on the actuator 662 (e.g., due to the common pressure in the upper chamber 776b and lower chamber 766c applying approximately equal upward and downward forces to the first piston assembly including the actuator 662). The effective piston areas may be approximately equal, for example, within 25%, 15%, 10%, 5%, or 2% of each other. Approximately equal piston areas can be applied to other suspension systems 860, 960, 1060, and 1160 described below.

[0119] The upper chamber 766b and the lower chamber 766c are in fluid communication with each other to maintain a substantially uniform pressure therein. Figure 7A and 7BAs shown, a circumferential gap 766d (e.g., an annular pressure chamber) extends between the upper chamber 776b and the lower chamber 766c to maintain fluid communication between them. For example, the circumferential gap 766d is radially defined between the upper housing 768 and the inner housing 662f of the actuator 662, and circumferentially defined about the axis of shaft 664. Furthermore, as described above, one or more support structures 780 connecting the actuator 662 to the upper housing 768 allow air to flow between the upper chamber 776b and the lower chamber 766c through the circumferential gap 766d. For example, the support structure 780 may be spokes spaced apart circumferentially to provide a flow path therebetween.

[0120] As the length of the suspension system 760 changes, the volume of the pressurization chamber 766a changes, and in particular, the volume of the lower chamber 766c changes, while the volume of the upper chamber 766b remains substantially constant. Therefore, when the volume of the pressurization chamber 766a increases or decreases for a given amount of air, air flows from the lower chamber 766c to the upper chamber 766b, or from the upper chamber 766b to the lower chamber 766c, respectively, to maintain a generally uniform air pressure therebetween. However, it should be noted that slight variations may occur between the upper chamber 766b and the lower chamber 766c when air flows between the upper chamber 766b and the lower chamber 766c and is confined within the circumferential gap 766d.

[0121] Referring to the second load path, which is formed by actuator 662, shaft 664, and upper housing 768, and is parallel to the first load path between top mounting bracket 774 and bottom mounting bracket 778, and thus between vehicle body 102 and unsprung component 306. More specifically, force is transmitted between top mounting bracket 774 and upper housing 768 via isolator 776, between upper housing 768 and actuator 662 via support structure 780, and between actuator 662 (i.e., its ball nut 662d) and bottom mounting bracket 778 via shaft 664.

[0122] As described above, the first load path supports the weight of the vehicle body 102 on the unsprung component 306, as well as a portion of the dynamic loads to the vehicle body 102 (e.g., weight transfer when the vehicle 100 is cornering or accelerating, or when a mass block moves within the vehicle 100) or to the unsprung component (e.g., when a wheel goes over a bump or through a pothole). The forces in the first load path are generally a function of the spring constant of the air spring 766 and the length (e.g., displacement) of the suspension system 760 (e.g., the distance between the vehicle body 102 and the unsprung component 306). The spring constant of the air spring 766 can be controlled by adding or removing air from the pressurization chamber 766a, but it can be controlled within a relatively small range (e.g., + / - 20%) and at a relatively low speed (e.g., bandwidth), which is limited by the rate at which air is supplied to or released from the pressurization chamber 766a.

[0123] The second load path is configured to control the force transmission between the body 102 and the unsprung component 306 due to dynamic loads (e.g., acting as a shock absorber). The force in the second load path is directly controlled by the actuator 662 (i.e., by applying torque from the motor 662a to the ball nut 662d, which in turn applies an axial force to the shaft 664). Compared to the first load path via the air spring 766, this force can be controlled over a larger range (e.g., a capacity of 0 kN + / - force) and at a relatively higher speed (e.g., bandwidth). Therefore, the actuator 662 can be operated to selectively apply an axial force to the shaft 664 (i.e., by selectively applying torque from the motor 662a to the ball nut 662d) to control the force transmission from the unsprung component 306 to the body 102 in response to dynamic loads or the anticipated dynamic load (e.g., in response to road disturbances or the anticipated road disturbance), while the air spring 766 can be controlled or uncontrolled in response to dynamic loads or the anticipated dynamic load.

[0124] As described above, the pressurization chamber 766a of the air spring 766 extends from the upper end of the suspension system 760 to the lower end (e.g., between the top mount 774 and the bottom mount 778), and may also include at least a portion of the actuator 662 (e.g., one or more or all of the motors 662a, including the rotor 662b and stator 662c, ball nut 662d and ball spline 662e) and shaft 664. This configuration offers various advantages over an air spring that is integrally arranged below the actuator 662, as opposed to an air spring mounted below the actuator 662. For example, the available volume of the pressurization chamber 766a can be larger and / or allow for a narrower package of the air spring 766 compared to an air spring mounted below the actuator 662. Additionally, an air spring otherwise mounted below the actuator 662 might need to be sealed to and move along the shaft 664, which could be difficult to perform given the slots 664a, 664b on its outer surface. In addition, the actuator 662 is protected from the external environment by being located in the pressurized chamber 766a without the need for an external protective cover (e.g., a bellows).

[0125] like Figure 7A As shown, the suspension system 760 may also include various electronic devices, schematically illustrated. These electronic devices may include the force sensor 671, motor electronics 663, and position sensor 665 previously described and incorporated into the top mount 771, and may also include a pressure sensor 766f. Such electronic devices may also be included in suspension systems 860, 960, 1060, and 1160 described below. Reference Figure 7C Electronic devices (i.e., force sensor 671, motor electronics 663, position sensor 665, and pressure sensor 766f) can communicate with control system 180, which can provide control signals to each of the suspension systems 660 (e.g., four suspension systems 660) for control. The vehicle may additionally include a pressurized gas source 790 in fluid communication with each of the suspension systems 760 (e.g., four suspension systems) of the vehicle 100, and it can be controlled by control system 180 to supply or release pressurized air from the air springs 766 of each of the suspension systems 760.

[0126] See Figures 8A to 8B Suspension system 860 is a variation of suspension system 760. Suspension system 860 typically includes actuator 862, shaft 664, air spring 866 with a pressurization chamber 866a, upper housing 868, lower housing 770, and diaphragm 772. Air spring 866 forms a first load path between top mount 774 and bottom mount 778. Actuator 862 and shaft 664 form a second load path between top mount 774 and bottom mount 778, and this load path may also include upper housing 868.

[0127] Actuator 862 is configured similarly to actuator 662 (e.g., by including motor 662a, ball nut 662d, ball spline 662e, and inner housing 662f), having a variation for mounting to upper housing 868 and for communicating air between upper chamber 866b and lower chamber 866c of pressurization chamber 866a. Shaft 664 is configured as described above. Air spring 866 is configured similarly to actuator 662 (e.g., by being defined by upper housing 868, lower housing 770, and diaphragm 772), having a variation on the configuration of upper chamber 866b of pressurization chamber 866a and communicating air between upper chamber 866b and lower chamber 866c. The upper housing 868 is configured similarly to the upper housing 768, having a variant for mounting the actuator 862 thereto, defining an upper chamber 866b, and connecting to a top mounting bracket 774. The lower housing 770 and the diaphragm 772 are configured as previously described. These variants will be described in further detail below.

[0128] Actuator 862 is mounted to upper housing 868 and / or top mounting bracket 774 via upper isolator 876a and lower isolator 876b. Each of upper isolator 876a and lower isolator 876b is configured similarly to the previously described isolator 776 by including an inner rigid ring and an outer rigid ring, with an intermediate compliant ring between the inner and outer rigid rings. Upper isolator 876a is radially positioned and rigidly coupled between upper housing 868 and / or top mounting bracket 774 and actuator 862. For example, the outer rigid ring of upper isolator 776a may be rigidly coupled to the inner surface of upper housing 868 and / or top mounting bracket 774a, while the inner rigid ring of upper isolator 776a may be rigidly coupled to the radially outer surface of inner housing 662f, such as to upper inner housing portion 662h. The upper isolator 876a is located axially above the motor 662a, such as above the stator 662c and / or the rotor 662b.

[0129] The lower isolator 876b is radially located between and rigidly connected to the upper housing 868 and the actuator 862. For example, the outer rigid ring of the lower isolator 876b may be rigidly connected to the radially inner surface of the upper housing 868, while the inner rigid ring of the lower isolator 876b may be rigidly connected to the radially outer surface of the inner housing 662f, such as to the lower inner housing portion 662g. The lower isolator 876b is axially spaced from the upper isolator 876a. For example, the lower isolator 876b is positioned below most of the axial length of the motor 662a (e.g., below most of the stator 662c), for example, connected to the lower inner housing portion 662g. Through this axial spacing, the upper isolator 876a and the lower isolator 876b cooperate to resist bending moments applied to the suspension system 860, for example, between the actuator 862a and the upper housing 868.

[0130] Actuator 862 is also configured to allow air to flow between the upper chamber 866b and the lower chamber 866c of the pressurization chamber 866a of the air spring 866. See also Figure 8B The pressurized chamber 866a, indicated by crosshairs, extends axially through the actuator 862a. Air communicates between the upper chamber 866b and the lower chamber 866c via the actuator, such as through axial channels in the inner housing 662f, channels and / or gaps between the inner housing 662f and the stator 662c, and / or between the rotor 662b and the stator 662c. Figure 8B It is shown schematically in the diagram.

[0131] Cavity 866a is typically defined between top mount 774 and bottom mount 778 by actuator 862 (e.g., its inner housing 662f), upper housing 868, lower housing 770, and diaphragm 772. Upper chamber 866b is typically located within upper housing 868, but is not defined or formed therefrom, but is defined or formed by the inner housing 662f of actuator 862, such that upper housing 868 is isolated from upper chamber 866b (e.g., not in fluid communication with it or not in fluid communication under pressure). As shown, the upper isolator 876a and the lower isolator 876b form a seal between the actuator 862 (e.g., its inner housing 662f) and the upper housing 868, thereby preventing the annular cavity 868e, which is radially defined between the actuator 862 and the upper housing 868 and axially defined between the upper isolator 876a and the lower isolator 876b, from fluid communication with the pressurization chamber 866a of the air spring 866 (e.g., the upper chamber 866b or otherwise). Therefore, the upper portion of the upper housing 868 is not subjected to air pressure within the pressurization chamber 866a.

[0132] The upper housing 868 can be rigidly connected to the top mounting bracket 774. For example, the upper housing 868 can be directly connected to the upper housing 868 and / or to the outer rigid ring of the isolator 776, which is then rigidly connected to the top mounting bracket 774.

[0133] Port 868a may be a variation of port 768a and is configured to deliver air to and from upper chamber 866b, but not to the area between the sealed and unpressurized regions between the upper housing 868 and the inner housing 662f of actuator 662.

[0134] Suspension system 860 achieves various advantages of suspension system 760. For example, the pressurization chamber 866a of air spring 866 extends from the upper end to the lower end of suspension system 860 (e.g., between top mount 774 and bottom mount 778), thus providing a relatively larger volume and / or narrower enclosure compared to an air spring mounted below actuator 662. By enclosing actuator 862 in upper housing 868, actuator 862 is protected from external environmental influences, while motor 662a (e.g., rotor 662b and stator 662c) is subjected to air pressure from pressurization chamber 866a. Furthermore, by accommodating shaft 664 in pressurization chamber 866a, it is not necessary to form a motion seal therein, which could be difficult to reliably perform with grooves 664a, 664b thereon.

[0135] As described above, the first load path is formed by an air spring 866, whereby pressurized gas in cavity 866a transmits the force of the first load path between the top mount 774 and the bottom mount 778. The second load path is parallel to the first load path and is formed by an actuator 862, whereby the force of the second load path is transmitted between the top mount 774 and the bottom mount 778 via shaft 664, ball nut 662d, inner housing 662f of actuator 662, isolators 876a and 876b (e.g., via their compliant intermediate rings), and housing 868. Housing 868 can function to define the pressure cavity 866a while also transmitting the force of the second load path. Isolator 876a can function to seal the pressurized cavity 866a of air spring 866 while also transmitting the force of the second load path. The pressurization chamber 866a may be defined by the top mounting bracket 774, the isolator 776, the housing 868, the flexible membrane 772 and the bottom mounting bracket 778, and may be further defined by the lower housing 770.

[0136] Referring to the above discussion of suspension systems 160, 660, and 760, further descriptions of the other parts and characteristic structures of suspension system 860 are obtained, including... Figures 8A to 8B Those marked in the middle.

[0137] See Figure 9 Suspension system 960 is a variation of suspension system 860. Suspension system 860 typically includes actuator 862, shaft 664, air spring 966 with a pressurization chamber 966a, upper housing 968, lower housing 770, and diaphragm 772. Air spring 966 forms a first load path between top mount 774 and bottom mount 778. Actuator 862 and shaft 664 form a second load path between top mount 774 and bottom mount 778, and this load path also includes upper housing 968.

[0138] The suspension system 960 differs from the suspension system 860 in that an annular cavity 968e (similar to annular cavity 868e) radially defined between the upper housing 968 and the actuator 862 communicates with the upper chamber 966b of the cavity. Therefore, the pressurization chamber 966a of the air spring 966 is defined or otherwise formed by the upper housing 968, which maintains air pressure within the pressurization chamber 966a. The actuator 862, particularly its inner housing 662f, does not seal the pressurization chamber 866a but remains contained within and subjected to pressure therein.

[0139] Please refer to the descriptions of suspension systems 160, 660, 760, and 860 above for further description of the other parts and structural features of suspension system 960, including... Figure 9 Those marked in the middle.

[0140] See Figure 10 Suspension system 1060 is a variation of suspension system 960. Suspension system 1060 typically includes actuator 862 (or alternatively actuator 662), shaft 664, air spring 966 with a pressurization chamber 966a, upper housing 1068, lower housing 770, and diaphragm 772. Air spring 966 forms a first load path between top mount 774 and bottom mount 778. Actuator 862 and shaft 664 form a second load path between top mount 774 and bottom mount 778, and this load path may also include upper housing 868.

[0141] The suspension system 1060 differs from suspension systems 760, 860, and 960 in that the upper housing 1068 does not form part of the second load path from the actuator 862 to the top mount 774. The upper isolator 876a and lower isolator 876b are omitted. Instead, the upper end of the actuator 862 is coupled to the top mount 774, with an intermediate top mount 1076 disposed therebetween. The intermediate top mount 1076 transmits the forces of the second load path between the actuators 862 (e.g., their inner housings 862g). The intermediate top mount 1076 also provides a similar damping function to the upper isolator 876a and / or lower isolator 876b by limiting movement between the actuators 862 and the top mount 774 (e.g., in rotational, radial, and axial directions) to suppress vibrations between them (e.g., due to the operation of the actuator 862 and / or road disturbances).

[0142] Please refer to the above descriptions of suspension systems 160, 660, 760, 860, and 960 for further descriptions of the other parts and structural features of suspension system 1060, including... Figure 10 Those marked in the middle.

[0143] See Figures 11A to 11B Suspension system 1160 is a variation of suspension system 860. Suspension system 1160 typically includes actuator 1162, shaft 664, air spring 1166 with a pressurization chamber 1166a, lower housing 770, and diaphragm 772. Air spring 1166 forms a first load path between top mount 774 and bottom mount 778. Actuator 1162 and shaft 664 form a second load path between top mount 774 and bottom mount 778.

[0144] The main difference between suspension system 1160 and suspension system 860 is the omission of the upper housing 868. Without the upper housing 868, the pressurization chamber 1166a is formed by the housing 1162f of actuator 1162, the lower housing 770, and a diaphragm 772 that seals the lower housing 770 to the housing of actuator 1162f. The omission of the upper housing 868 relatively simplifies and reduces the weight of suspension system 1160. The chamber 1166a is identified by crosshairs in Figure 11.

[0145] Actuator 1162 is a variation of actuator 862. Actuator 1162 includes motor 662a (i.e., including rotor 662b and stator 662c), ball nut 662d and ball spline 662e, and housing 1162f. Housing 1162f is a variation of inner housing 662f, which extends further downward relative to actuator 662.

[0146] The outer casing 1162f is a rigid ring structure, which typically includes an upper outer casing portion 1162g and a lower outer casing portion 1162h, which are connected to or integrally formed with each other as previously described. The outer casing 1162f may include more or fewer components than the upper outer casing portion 1162g and the lower outer casing portion 1162h.

[0147] The housing 1162f may be constructed, for example, around the motor 662a (e.g., fixedly coupled to the stator 662c and / or rotatably supported by the upper bearing assembly 678) and including cooling channels (shown; not labeled) to resemble the upper inner housing portion 662h.

[0148] The upper end of actuator 1162 (e.g., the upper end of upper housing portion 1162g) is coupled to top mount 774 via isolator 1176. Isolator 1176 can be configured, for example, as a tubular isolator or bushing similar to isolator 776 by having an inner rigid ring and an outer rigid ring coupled to and separated by an intermediate compliant ring. For example, isolator 1176 is rigidly coupled to each of actuator 1162 and top mount 774, wherein the outer rigid ring is coupled to top mount 774 and the inner rigid ring is coupled to actuator 1162 (e.g., coupled to housing 1162f, such as the upper housing portion 1162g on its radially outer surface).

[0149] In an alternative arrangement, the outer rigid ring of the isolator 1176 may be coupled to the housing 1162f of the actuator 1162 (e.g., coupled to its inner surface), while the inner rigid ring of the isolator 1176 is coupled to the top mount 774 (e.g., to an axially extending portion, such as the annular flange described above relative to the force sensor of the suspension system 760 or the top mount 774). By providing the isolator 1176 radially inward of the housing 1162f, various packaging advantages can be provided, for example, by allowing the force sensor of the top mount 774 to be smaller and / or positioned within the isolator 1176. The housing 1162f of the actuator 1162 can be considered as the housing of the suspension system 1160.

[0150] The upper housing portion 1162g defines the upper chamber 1166b of the pressurized chamber 1166a. An isolator 1176 is used to seal the housing 1162f of the actuator 1162 to the top mounting bracket 774 to define a portion of the pressurized chamber 1166a of the air spring 1166. Similar to the previously described upper chambers 766b, 866b, the upper chamber 1166b may house a motor 662a (e.g., rotor 662b and stator 662c) subjected to pressurized air.

[0151] The upper housing portion 1162g also includes a port 1168a through which air alternately enters and exits the pressurization chamber 1166a. For example, as described above, air can be added to or removed from the pressurization chamber 1166a to raise or lower the vehicle's ride height (e.g., by moving the body 102 relative to the unsprung component 306).

[0152] In various respects, the lower outer shell portion 1162h can be configured to resemble the lower inner outer shell portion 662g, for example, by including an inner annular portion 1162j that surrounds the ball nut 662d and / or the ball spline 662e (e.g., fixed to the ball spline 662e and / or rotatably supported by a bearing assembly 676 (such as a thrust bearing)).

[0153] The lower outer shell portion 1162h is hermetically connected to the lower outer shell 770 via a membrane 772, such that the lower outer shell portion 1162h, the outer shell 770, and the membrane 772 together define the lower chamber 1166c of the pressurization chamber 1166a of the air spring. For example, the lower outer shell portion 1162h includes an outer annular portion 1162k to which the membrane 772 is connected. When the suspension system 1160 changes length, the outer annular portion 1162k of the lower outer shell portion 1162h and the lower outer shell 770 translate relative to each other (e.g., the lower outer shell 770 receives the outer shell 1162f therein), and the inner and outer portions of the membrane 772 translate relative to each other (as previously described).

[0154] The outer annular portion 1162k may be located radially outside the inner annular portion 1162j to define an annular passage 1162l therebetween. When the length of the suspension system 1160 changes or air is added to or removed from the pressurization chamber 1166a, air passes through the annular passage 1162l between the upper chamber 1166b and the lower chamber 1166c of the pressurization chamber 1166a.

[0155] Actuator 1162 is configured similarly to actuator 862 to allow air to pass between upper chamber 1166b and lower chamber 1166c, such as through axial channels in housing 1162f, channels and / or gaps between housing 1162f and stator 662c and / or rotor 662b and stator 662c, such channels and / or gaps in Figure 11B It is shown schematically in the diagram.

[0156] As described above, the first load path is formed by the air spring 1166, through which pressurized gas in cavity 1166a transmits the force of the first load path between the top mount 774 and the bottom mount 778. The second load path is parallel to the first load path and is formed by the actuator 1162, through which the force of the second load path is transmitted between the top mount 774 and the bottom mount 778 via shaft 664, ball nut 662d, housing 1162f, and isolator 1176 (e.g., via its compliant intermediate ring) (e.g., via its intermediate ring). Housing 1162f can function to define the pressurized cavity 1166a while also transmitting the force of the second load path. Isolator 1176 can function to seal the pressurized cavity 1166a of the air spring 1166 while also transmitting the force of the second load path. The pressurization chamber 1166a may be jointly defined by the top mounting bracket 1174, the isolator 1176, the housing 1162f of the actuator 1162, the flexible diaphragm 772, and the bottom mounting bracket 774, and may be further defined by another housing coupled to the bottom mounting bracket. The housing 1162g of the actuator 1162 may form the outer housing of the suspension system 1160.

[0157] Refer to the above descriptions of suspension systems 160, 660, 760, 860, 960, and 1060 for further description of the other parts and structural features of suspension system 1160, including... Figures 11A to 11B Those marked in the middle.

[0158] Although this disclosure has been described in conjunction with certain embodiments, it should be understood that this disclosure is not limited to the disclosed embodiments, but rather is intended to cover all modifications and equivalent arrangements included within the scope of the appended claims, which shall be given the broadest interpretation to cover all such modifications and equivalent structures permitted by law.

Claims

1. A suspension actuator, comprising: Top mounting bracket; Bottom mounting bracket; The upper housing extends from the top mounting bracket; The lower housing extends from the bottom mounting bracket; An air spring configured to form a first load path between a first part of a vehicle and a second part of the vehicle, the air spring including a pressurization chamber having an upper cavity defined by the upper housing, a lower cavity defined by the lower housing, and a membrane extending radially between the upper housing and the lower housing, wherein the pressurization chamber is configured to receive pressurized gas that transmits forces through the first load path; as well as A ball screw actuator is configured to form a second load path between the first portion and the second portion of the vehicle, parallel to the first load path, the ball screw actuator including a motor coupled to the upper housing and having a stator and a rotor. An airflow path is defined radially outward from the stator, such that the upper and lower cavities of the pressurized chamber are in fluid communication with each other through the airflow path.

2. The suspension actuator of claim 1, wherein the motor of the ball screw actuator is contained in the pressurization chamber.

3. The suspension actuator according to claim 1 or 2, wherein the airflow path is defined by a channel between the upper housing and the stator.

4. The suspension actuator according to claim 1 or 2, wherein the airflow path is defined by the gap between the upper housing and the stator.

5. The suspension actuator according to claim 1 or 2, wherein the airflow path is defined by an axial channel in the upper housing.

6. The suspension actuator according to claim 1 or 2, wherein the ball screw actuator further comprises: axis; A ball nut, to which the motor applies torque to transmit the force of the second load path between the upper housing and the shaft; A ball spline applies torque to the shaft to prevent it from rotating relative to the upper housing.

7. The suspension actuator of claim 6, wherein the upper housing, the stator and the ball spline are coupled to each other to form a stationary assembly, and the rotor and the ball nut are coupled to each other to form a rotating assembly, the rotating assembly being rotatably supported by a thrust bearing and axially fixed to the stationary assembly.

8. The suspension actuator of claim 7, wherein the thrust bearing is coupled to the ball nut and the stator housing.

9. The suspension actuator of claim 1 or 2, wherein the upper housing transmits the force of the second load path.

10. The suspension actuator of claim 9, wherein the stator contacts the inner surface of the upper housing.

11. The suspension actuator of claim 6, wherein the upper housing surrounds the motor and the ball nut.

12. The suspension actuator of claim 1 or 2, wherein the upper housing surrounds the motor and includes a cooling channel for receiving fluid for cooling the motor.

13. The suspension actuator according to claim 1 or 2, wherein the upper end of the upper housing is coupled to the top mounting bracket by means of an isolator.

14. The suspension actuator of claim 13, wherein the isolator comprises an inner rigid ring and an outer rigid ring coupled to and separated by the intermediate compliance ring.

15. A suspension actuator, comprising: Upper outer shell; Lower outer shell; An air spring is disposed between the upper housing and the lower housing and is configured to form a first load path between the sprung mass and the unsprung mass of the vehicle; as well as A ball screw actuator is configured to form a second load path between the sprung mass and the unsprung mass, parallel to the first load path, the ball screw actuator comprising: A motor coupled to the upper housing and having a stator and a rotor, axis, A ball nut, to which the motor applies torque to transmit the force of the second load path between the upper housing and the shaft; A ball spline applies torque to the shaft to prevent its rotation relative to the upper housing. The upper housing, the stator, and the ball spline are coupled to each other to form a fixed assembly, and the rotor and the ball nut are coupled to each other to form a rotating assembly, the rotating assembly being rotatably supported by a thrust bearing and axially fixed to the fixed assembly.

16. The suspension actuator of claim 15, wherein the thrust bearing is coupled to the ball nut and the stator housing.

17. The suspension actuator of claim 16, wherein the rotating component is further rotatably supported by the stator housing via another bearing coupled to the upper housing and the rotor.

18. The suspension actuator of claim 17, wherein the other bearing is spaced apart from the thrust bearing and is axially positioned above the thrust bearing.

19. The suspension actuator of claim 17 or 18, wherein the stator is axially positioned between the thrust bearing and the other bearing.

20. A suspension actuator, comprising: Upper outer shell; Lower outer shell; An air spring configured to form a first load path between the body of a vehicle and the wheels of the vehicle, the air spring including a pressurization chamber having an upper cavity defined by the upper housing, a lower cavity defined by the lower housing, and a membrane extending radially between the upper housing and the lower housing, wherein the pressurization chamber is configured to receive pressurized gas that transmits the force of the first load path; as well as A ball screw actuator is configured to form a second load path between the vehicle body and the wheel, parallel to the first load path, the ball screw actuator including a motor. The upper housing surrounds the motor and includes a cooling channel for receiving fluid used to cool the motor.

21. The suspension actuator of claim 20, wherein the motor comprises a stator and a rotor, wherein the stator contacts the inner surface of the upper housing.

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