Vehicle suspension system with passive and active roll control

Abstract

A suspension system includes four shock absorbers, each of which is provided with a compression chamber and a rebound chamber. A first and second hydraulic circuit interconnects the compression and rebound chambers of the front shock absorbers, and a third and fourth hydraulic circuit interconnects the compression and rebound chambers of the rear shock absorbers. A first longitudinal hydraulic line extends between and connects the first and third hydraulic circuits, and a second longitudinal hydraulic line extends between and connects the second and fourth hydraulic circuits. A first bi-directional pump is in series with a fluid distribution line that extends between and connects the first and second longitudinal hydraulic lines, the pump being operable to pump fluid bi-directionally through the fluid distribution line to provide active roll stiffness.

Description

Technical Field

[0001] This disclosure relates generally to motor vehicle suspension systems, and more specifically to suspension systems capable of resisting vehicle pitch and roll movements. Background Technology

[0002] The statements in this section provide only background information in connection with this disclosure and may not constitute prior art.

[0003] Suspension systems improve ride comfort by absorbing bumps and vibrations that could otherwise cause instability. They also enhance safety and handling by increasing tire contact with the road. However, a drawback of suspension systems is that the basic spring / damper arrangement causes the vehicle to tilt / roll over when cornering (e.g., during turns), lunge forward when decelerating (e.g., during braking), and pitch backward when accelerating. Lateral acceleration during cornering generates roll moments, with left turns resulting in a rightward tilt / roll and right turns in a leftward tilt / roll. Rear-end acceleration during acceleration and braking generates pitch moments, causing forward tilt / surge during braking, loading the front axle; and rearward tilt / sag during acceleration, loading the rear axle. These roll and pitch moments reduce grip, cornering performance, and braking performance, while also causing discomfort to the driver and passengers. Many vehicles are equipped with stabilizer bars / anti-roll bars, mechanical systems that effectively counteract roll moments generated during driving. For example, an anti-roll bar is typically a mechanical link spanning the width of the vehicle between the left and right shock absorbers. When one shock absorber extends, the anti-roll bar applies force to the other to counteract the vehicle's roll moment, helping to correct the roll angle for smoother cornering. However, this type of mechanical system has several drawbacks: First, the system is often limited by installation space, as the stabilizer bar / anti-roll bar requires a relatively straight and unobstructed lateral mounting path between the shock absorbers; second, the stabilizer bar / anti-roll bar is passive, only working when the suspension begins to move (i.e., tilt), and therefore cannot actively prevent roll; moreover, this type of mechanical system is difficult to disable or disengage when roll stiffness is not required. While some vehicles are equipped with manually or electronically operated anti-roll bar disconnect devices, their complexity and cost make them unsuitable for most vehicles. Furthermore, traditional stabilizer bars / anti-roll bars do not provide additional pitch stiffness or pitch control.

[0004] To enhance or replace traditional mechanical stabilizer bars / anti-roll bars, anti-roll suspension systems are being developed. These systems connect two or more shock absorbers via a hydraulic circuit. When one shock absorber extends, it causes pressure changes in the other shock absorbers in the hydraulic circuit, making it more difficult for the other shock absorber(s) in the hydraulic circuit to compress. This pressure change in the other shock absorbers increases the roll stiffness of the vehicle's suspension system. However, a drawback of this type of system is that because bump forces are transmitted from one shock absorber to another through the hydraulic circuit, unwanted suspension movements can occur, making it difficult to guarantee ride comfort. Therefore, there is still a need for improved vehicle suspension systems that can minimize roll, pitch, and other undesirable suspension movements while maintaining acceptable ride comfort. Summary of the Invention

[0005] This section provides a general description of the contents of this disclosure and is not an exhaustive disclosure of its full scope or all its features.

[0006] According to one aspect of this disclosure, a suspension system comprising four shock absorbers is provided: a left front shock absorber, a right front shock absorber, a left rear shock absorber, and a right rear shock absorber. The left front shock absorber includes a first compression chamber and a first rebound chamber; the right front shock absorber includes a second compression chamber and a second rebound chamber; the left rear shock absorber includes a third compression chamber and a third rebound chamber; and the right rear shock absorber includes a fourth compression chamber and a fourth rebound chamber.

[0007] The suspension system disclosed herein also includes four hydraulic circuits: a first hydraulic circuit establishes fluid communication between the first compression chamber of the left front shock absorber and the second rebound chamber of the right front shock absorber; a second hydraulic circuit establishes fluid communication between the first rebound chamber of the left front shock absorber and the second compression chamber of the right front shock absorber; a third hydraulic circuit establishes fluid communication between the third compression chamber of the left rear shock absorber and the fourth rebound chamber of the right rear shock absorber; and a fourth hydraulic circuit establishes fluid communication between the third rebound chamber of the right rear shock absorber and the fourth compression chamber of the right rear shock absorber. The suspension system also includes: a first longitudinal hydraulic line extending between the first and third hydraulic circuits and achieving fluid connection between them; a second longitudinal hydraulic line extending between the second and fourth hydraulic circuits and achieving fluid connection between them; and a fluid distribution line extending between the first and second longitudinal hydraulic lines and achieving fluid connection between them.

[0008] The suspension system disclosed herein also includes a first bidirectional pump arranged and in fluid communication with a fluid distribution pipe. The first bidirectional pump has a first operating mode and a second operating mode, the first operating mode for pumping hydraulic fluid in a first direction through the fluid distribution pipe to a second longitudinal hydraulic line; and the second operating mode for pumping hydraulic fluid in a second direction through the fluid distribution pipe to the first longitudinal hydraulic line. Therefore, passive roll stiffness is provided when the first bidirectional pump is inactive, while active roll stiffness is provided when the first bidirectional pump is operating in the first and second operating modes.

[0009] According to another aspect of this disclosure, the suspension system also includes a controller electrically connected to the first bidirectional pump. This controller is programmed to start / stop the first bidirectional pump, thereby activating different suspension operating modes (e.g., comfort operating mode, passive roll control operating mode, active roll control operating mode, and pressure control operating mode).

[0010] According to another aspect of this disclosure, the suspension system further includes a second bidirectional pump arranged and in fluid communication with a first longitudinal hydraulic line, and a third bidirectional pump arranged and in fluid communication with a second longitudinal hydraulic line. The second bidirectional pump has a third operating mode and a fourth operating mode. The third operating mode is used to pump hydraulic fluid from a third hydraulic circuit to a first hydraulic circuit via the first longitudinal hydraulic line in a third direction, and the fourth operating mode is used to pump hydraulic fluid from the first hydraulic circuit to the third hydraulic circuit via the first longitudinal hydraulic line in a fourth direction. The third bidirectional pump has a fifth operating mode and a sixth operating mode. The fifth operating mode is used to pump hydraulic fluid from the fourth hydraulic circuit to the second hydraulic circuit via the second longitudinal hydraulic line in a fifth direction, and the sixth operating mode is used to pump hydraulic fluid from the second hydraulic circuit to the fourth hydraulic circuit via the second longitudinal hydraulic line in a sixth direction. The controller controls the operation of the second and third bidirectional pumps to achieve additional suspension operating modes (e.g., roll moment distribution control operating mode, pitch control operating mode, and torsion control operating mode).

[0011] Advantageously, the suspension system disclosed herein can reduce / eliminate vehicle pitch and roll motion, thereby improving grip, performance, handling, and braking. The reduction in pitch and roll angles enhances vehicle comfort, steering feel, agility, and stability. Pitch and roll control is achieved by increasing the pitch or roll stiffness of the suspension system based on fluid pressure within the system. The pitch and roll stiffness levels can be adjusted by changing the pressure in a specific hydraulic circuit within the system using a two-way pump. When additional pitch / roll stiffness is not required or not needed, valves in the hydraulic circuit can also be opened to decouple the shock absorbers. Attached Figure Description

[0012] Other advantages of this disclosure will be readily apparent, as they become clearer when considered in conjunction with the accompanying drawings and with reference to the following detailed description, wherein:

[0013] Figure 1 This is a schematic diagram illustrating an exemplary vehicle suspension system as it experiences vertical heave, pitch, roll, and warp.

[0014] Figure 2 This is a schematic diagram illustrating an exemplary suspension system of the present disclosure, which includes a centralized bidirectional pump;

[0015] Figure 3 It is shown Figure 2 The diagram shows an exemplary suspension system operating in the first comfort mode.

[0016] Figure 4 It is shown Figure 2 The diagram shows an exemplary suspension system operating in the second comfort mode.

[0017] Figure 5 It is shown Figure 2 A schematic diagram of an exemplary suspension system operating in passive roll control mode;

[0018] Figure 6 It is shown Figure 2 The diagram shows an exemplary suspension system operating in active roll control mode.

[0019] Figure 7 It is shown Figure 2 The diagram shows an exemplary suspension system operating in pressure control mode.

[0020] Figure 8 This is a schematic diagram illustrating another exemplary suspension system of the present disclosure, which includes a centralized dual-chamber ball screw mechanism and a bidirectional pump;

[0021] Figure 9 This is a schematic diagram illustrating another exemplary suspension system of the present disclosure, which includes three bidirectional pumps;

[0022] Figure 10 It is shown Figure 9 The diagram shows an exemplary suspension system operating in the first comfort mode.

[0023] Figure 11 It is shown Figure 9 The diagram shows an exemplary suspension system operating in the second comfort mode.

[0024] Figure 12 It is shown Figure 9The diagram shows an exemplary suspension system operating in passive roll control mode.

[0025] Figure 13 It is shown Figure 9 The diagram shown illustrates the suspension system in active roll control mode.

[0026] Figure 14 It is shown Figure 9 The diagram shown illustrates the operation of an example suspension system in active roll moment distribution control mode.

[0027] Figure 15 It is shown Figure 9 The diagram shown illustrates the example suspension system operating in active pitch control mode.

[0028] Figure 16 It is shown Figure 9 The diagram shown illustrates the example suspension system operating in active torsion control mode.

[0029] Figure 17 It is shown Figure 9 The diagram shown illustrates the example suspension system operating in fully adaptive active control mode; and

[0030] Figure 18 It is shown Figure 9 The diagram shows an exemplary suspension system operating in pressure control mode. Detailed Implementation

[0031] Referring to the accompanying drawings (where the same numbers denote corresponding components in each view), various suspension systems equipped with comfort valves are shown.

[0032] Exemplary embodiments will now be described in more detail with reference to the accompanying drawings. Exemplary embodiments are provided to make this disclosure comprehensive and to fully communicate its scope to those skilled in the art. Numerous specific details, such as examples of particular components, apparatuses, and methods, are set forth to aid in a full understanding of the embodiments of this disclosure. Those skilled in the art will understand that exemplary embodiments may be embodied in many different forms without the need for specific details, and none should be construed as limiting the scope of this disclosure. In some exemplary embodiments, known processes, known apparatus structures, and known technologies are not described in detail.

[0033] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “the” may also include the plural forms. The terms “comprising,” “containing,” “including,” and “having” are open-ended descriptions, meaning that the stated features, elements, steps, operations, components, and / or parts are explicitly present, but do not preclude the possibility of the presence or addition of one or more other features, elements, steps, operations, components, and / or combinations thereof. The method steps, processes, and operations described herein, unless explicitly specified as the order of execution, should not be construed as necessarily having to be performed in the specific order shown in the discussion or diagrams. It should also be understood that additional or alternative steps may be employed.

[0034] When an element or layer is described as being "above," "joined to," "connected to," or "coupled to" another element or layer, it may be directly above, joined to, connected to, or coupled to that element or layer, or there may be intermediate elements or layers. Conversely, when an element is described as being "directly above," "directly joined to," "directly connected to," or "directly coupled to" another element or layer, there are no intermediate elements or layers. Other terms describing relationships between elements should be interpreted similarly (e.g., "between" vs. "directly between," "adjacent" vs. "directly adjacent," etc.). The term "and / or" in this document covers any combination of one or more of the listed related terms.

[0035] Although terms such as “first,” “second,” and “third” may be used herein to describe various elements, components, regions, layers, and / or portions, these elements, components, regions, layers, and / or portions should not be limited by these terms. These terms are used only to distinguish different regions, layers, or portions. Numerical terms such as “first” and “second” as used in this specification do not imply order or sequence unless explicitly indicated by the context. Therefore, the first element, component, region, layer, or portion described below may also be referred to as a second element, component, region, layer, or portion without departing from the teachings of the exemplary embodiments.

[0036] Spatial relative terms (such as "inner side," "outer side," "below," "below," "lower part," "above," "upper part," etc.) are used in this specification for ease of description to illustrate the relative relationship between a component or feature in the illustrations and other components or features. Spatial relative terms may cover not only the orientation of the illustrated device but also different orientations during use or operation. For example, if the illustrated device is flipped, a component originally described as "below" or "below" will become "above." Therefore, the term "below" can encompass both the upper and lower orientations. The device may be in other orientations (rotated 90 degrees or other angles), and the spatial relative descriptive terms used herein should be interpreted accordingly.

[0037] In this application, the term "controller" may be replaced with "circuit". For example, the term "controller" may refer to, constitute, or include: application-specific integrated circuit (ASIC); digital, analog, or mixed-signal analog / digital discrete circuit; digital, analog, or mixed-signal analog / digital integrated circuit; combinational logic circuit; field-programmable gate array (FPGA); processor circuit (shared, dedicated, or grouped) storing processor circuit execution code; memory circuit (shared, dedicated, or grouped) storing processor circuit execution code; other suitable hardware components that provide the aforementioned functionality; or combinations of some or all of the above (such as combinations in a system-on-chip).

[0038] The controller may include one or more interface circuits. In some embodiments, the interface circuits may include wired or wireless interfaces for connecting to a local area network (LAN), the Internet, a wide area network (WAN), or a combination thereof. The functionality of any particular module in this disclosure may be distributed across multiple modules connected via the interface circuits. For example, a multi-module configuration can achieve load balancing. In another example, a server (also known as a remote or cloud) module may perform some functions on behalf of a client module.

[0039] The term "code" as used above can encompass software, firmware, and / or microcode, and can refer to programs, routines, functions, classes, data structures, and / or objects. "Shared processor circuitry" refers to a single processor circuitry that executes part or all of the code for multiple modules. "Group processor circuitry" refers to a processor circuitry that collaborates with other processor circuitry to execute part or all of the code for one or more modules. References to multiple processor circuitry encompass: multiple processor circuitry on a standalone chip, multiple processor circuitry on a single chip, multi-core processor circuitry, multi-threaded processor circuitry, or a combination of the above. The term "shared memory circuitry" refers to a single memory circuitry that stores part or all of the code for multiple modules. The term "group memory circuitry" refers to a memory circuitry that stores part or all of the code for one or more modules in combination with other memories.

[0040] The term "memory circuit" is a subset of the term "computer-readable medium." As used herein, the term "computer-readable medium" does not cover transient electrical or electromagnetic signals (such as carrier signals) propagating through a medium; therefore, the term "computer-readable medium" can be considered as a tangible and non-transient medium. Non-limiting examples of non-transient tangible computer-readable media include: non-volatile memory circuits (such as flash memory circuits, erasable programmable read-only memory circuits, or mask read-only memory circuits), volatile memory circuits (such as static random access memory circuits or dynamic random access memory circuits), magnetic storage media (such as analog or digital magnetic tape, hard disk drives), and optical storage media (such as CDs, DVDs, or Blu-ray discs).

[0041] A computer program contains processor-executable instructions stored on at least one non-transitory, tangible, computer-readable medium. A computer program may also contain or rely on stored data. The scope of a computer program includes: a basic input / output system (BIOS) for interacting with dedicated computer hardware; device drivers for interacting with specific devices of a dedicated computer; one or more operating systems; user applications; background services; background applications, etc.

[0042] Computer programs may contain: (i) descriptive text to be parsed, such as HTML (Hypertext Markup Language), XML (Extensible Markup Language), or JSON (JavaScript Object Notation); (ii) assembly code; (iii) object code generated by a compiler from source code; (iv) source code for execution by an interpreter; and (v) source code for compilation and execution by a just-in-time (JIT) compiler. For example, source code may be written in the syntax of languages ​​such as C, C++, C#, Objective-C, Swift, Haskell, Go, SQL, R, Lisp, Java®, Fortran, Perl, Pascal, Curl, OCaml, JavaScript®, HTML5 (Hypertext Markup Language 5th Edition), Ada, ASP (Active Server Pages), PHP (Hypertext Preprocessor), Scala, Eiffel, Smalltalk, Erlang, Ruby, Flash®, Visual Basic®, Lua, MATLAB, SIMULINK, and Python®.

[0043] Reference Figure 1 The diagram illustrates a vehicle suspension system 100. The vehicle includes a left front wheel 101a, a right front wheel 101b, a left rear wheel 101c, and a right rear wheel 101d. It should be noted that the actual number of wheels may differ from the stated number. Figure 1 The figures may differ, but in most automotive applications, a wheel is positioned at each corner of the vehicle body 103, for a total of four wheels. For example... Figure 1 As shown, a vehicle experiences four types of suspension movements in daily operation: vertical sway, pitch, roll, and torsion. When the vehicle suspension system 100 experiences vertical sway, the vehicle body 103 will lift (e.g., ...). Figure 1 As shown), for example, when a vehicle travels over a hill (i.e., a slope), or when the vehicle body dips (e.g., when a vehicle travels over a depression in the road surface, i.e., a valley), all four wheels 101a-101d simultaneously or nearly simultaneously move downwards (not shown) or upwards 105a-105d (as shown in the figure). When the vehicle suspension system 100 pitches, the front of the vehicle body 103 rises and the rear dips (e.g., during rapid acceleration), or the front of the vehicle body 103 dips and the rear rises (e.g., during emergency braking). Figure 1 In the pitch example shown, the front of the vehicle body 103 rises while the rear sinks (i.e., pitching aft). At this time, the front wheels 101a and 101b move upwards (107a and 107b), while the rear wheels 101c and 101d move downwards. The opposite occurs when the front of the vehicle body 103 sinks and the rear rises (i.e., pitching forward). When the vehicle suspension system 100 rolls, the right side of the vehicle body 103 rises while the left side sinks (e.g., during a sharp right turn), or the right side of the vehicle body 103 sinks while the left side rises (e.g., during a sharp left turn). Figure 1 In the roll example shown, when the right side of the vehicle body 103 rises and the left side sinks (i.e., tilts to the left), the right wheels 101b and 101d move upwards 109b and 109d, while the left wheels 101a and 101c move downwards 109a and 109c. The opposite occurs when the right side of the vehicle body 103 sinks and the left side rises (i.e., tilts to the right). When the vehicle suspension system 100 twists, the right front wheel and left rear wheel 101b and 101c will move upwards (i.e., lift) 111b and 111c, while the left front wheel and right rear wheel 101a and 101d will move downwards (i.e., sink) 111a and 111d (as shown). Figure 1 As shown in the diagram, the right front wheel 101b and left rear wheel 101c may sink downwards, while the left front wheel 101a and right rear wheel 101d may rise upwards. This will be explained in detail below; the design goal of this suspension system 100 is precisely to reduce or eliminate these various displacements.

[0044] Reference Figure 2 The suspension system 100 includes a left front shock absorber 102a, a right front shock absorber 102b, a left rear shock absorber 102c, and a right rear shock absorber 102d. It should be noted that although the number of shock absorbers in the suspension system 100 described herein may differ from the illustration, in most automotive applications, a shock absorber is installed at each of the four corners of the vehicle, for a total of four, to control the vertical movement of the front and rear wheels 101a-101d.

[0045] Each shock absorber 102a, 102b, 102c, 102d in the suspension system 100 includes a shock absorber housing 104a, 104b, 104c, 104d, a piston rod 106a, 106b, 106c, 106d, and pistons 108a, 108b, 108c, 108d mounted on the piston rod 106a, 106b, 106c, 106d. Pistons 108a, 108b, 108c, 108d are closed pistons, and their internal structure does not define any fluid passages. Pistons 108a, 108b, 108c, and 108d are slidably fitted inside damper housings 104a, 104b, 104c, and 104d, such that each piston divides each damper housing 104a, 104b, 104c, and 104d into a compression chamber and a rebound chamber. Therefore, the left front damper 102a includes a first compression chamber 126a and a first rebound chamber 128a; the right front damper 102b includes a second compression chamber 126b and a second rebound chamber 128b; the left rear damper 102c includes a third compression chamber 126c and a third rebound chamber 128c; and the right rear damper 102d includes a fourth compression chamber 126d and a fourth rebound chamber 128d. The rebound chambers 128a, 128b, 128c, and 128d of dampers 102a, 102b, 102c, and 102d decrease in volume during the rebound / extension stroke and increase in volume during the compression stroke. The compression chambers 126a, 126b, 126c, and 126d of dampers 102a, 102b, 102c, and 102d decrease in volume during the compression stroke and increase in volume during the rebound / extension stroke.

[0046] The first compression chamber 126a of the left front shock absorber 102a is fluidly connected to the second rebound chamber 128b of the right front shock absorber 102b via a first hydraulic circuit 120a. The first hydraulic circuit 120a includes a first hydraulic line 132a that extends between the first compression chamber 126a of the left front shock absorber 102a and the second rebound chamber 128b of the right front shock absorber 102b, thus achieving fluid connection between them. The first rebound chamber 128a of the left front shock absorber 102a is fluidly connected to the second compression chamber 126b of the right front shock absorber 102b via a second hydraulic circuit 120b. The second hydraulic circuit 120b includes a second hydraulic line 132b that extends between the first rebound chamber 128a of the left front shock absorber 102a and the second compression chamber 126b of the right front shock absorber 102b, thus achieving fluid connection between them. Therefore, the first and second hydraulic lines 132a and 132b of the first and second hydraulic circuits 120a and 120b intersect each other at the first intersection point 190.

[0047] The third compression chamber 126c of the left rear shock absorber 102c is fluidly connected to the fourth rebound chamber 128d of the right rear shock absorber 102d via a third hydraulic circuit 120c. The third hydraulic circuit 120c includes a third hydraulic line 132c that extends between the third compression chamber 126c of the left rear shock absorber 102c and the fourth rebound chamber 128d of the right rear shock absorber 102d, thus establishing a fluid connection between them. The third rebound chamber 128c of the left rear shock absorber 102c is fluidly connected to the fourth compression chamber 126d of the right rear shock absorber 102d via a fourth hydraulic circuit 120d. The fourth hydraulic circuit 120d includes a fourth hydraulic line 132d that extends between the third rebound chamber 128c of the left rear shock absorber 102c and the fourth compression chamber 126d of the right rear shock absorber 102d, thus establishing a fluid connection between them. Therefore, the third and fourth hydraulic lines 132c and 132d of the third hydraulic circuit 120c and the fourth hydraulic circuit 120d intersect each other at the second intersection point 192.

[0048] The suspension system 100 includes a first longitudinal hydraulic line 130a, a second longitudinal hydraulic line 130b, and a fluid distribution line 131. The first longitudinal hydraulic line 130a extends between a first hydraulic circuit 120a and a third hydraulic circuit 120c, achieving fluid connection between the two; the second longitudinal hydraulic line 130b extends between a second hydraulic circuit 120b and a fourth hydraulic circuit 120d, achieving fluid connection between the two; the fluid distribution line 131 extends between the first longitudinal hydraulic line 130a and the second longitudinal hydraulic line, and is fluidly connected to both the first longitudinal hydraulic line 130a and the second longitudinal hydraulic line. A bidirectional pump 110 is arranged along and connected in series with the fluid distribution line 131, dividing the fluid distribution line 131 into a first distribution line segment 133a and a second distribution line segment 133b. The first distribution line section 134a extends between the first longitudinal hydraulic line 130a and the first port 116a on the bidirectional pump 110 and fluidly connects them; the second distribution line section 133b extends between the second longitudinal hydraulic line 130b and the second port 116b on the bidirectional pump 110 and fluidly connects them.

[0049] like Figures 2 to 7In the illustrated arrangement, fluid distribution line 131 is connected to hydraulic fluid reservoir 112 (e.g., oil tank) via reservoir line 114. Reservoir line 114 extends between hydraulic fluid reservoir 112 and the first distribution section 133a of fluid distribution line 131, enabling fluid communication between the two. However, it should be noted that reservoir line 114 can also extend between hydraulic fluid reservoir 112 and the second distribution section 133b of fluid distribution line 131, enabling fluid communication between the two. The bidirectional pump 110 can operate in two opposite directions (i.e., pump fluid) depending on the polarity of the current supplied to it. Therefore, the first port 116a of the bidirectional pump 110 can be used as either an inlet or outlet depending on the pump's operating direction, and its second port 116b follows the same principle. Therefore, the bidirectional pump 110 can operate to draw hydraulic fluid from the first distribution section 133a of the fluid distribution line 131 (and thus from the first longitudinal hydraulic line 130a or the reservoir line 114) and deliver it to the second distribution section 133b of the fluid distribution line 131 (and thus to the second longitudinal hydraulic line 130b). The bidirectional pump 110 can also operate in reverse, drawing hydraulic fluid from the second distribution section 133b of the fluid distribution line 131 (and thus from the second longitudinal hydraulic line 130b) and delivering it to the first distribution section 133a of the fluid distribution line 131 (and thus to the first longitudinal hydraulic line 130a or the reservoir line 114).

[0050] In this example, when the first port 116a operates as the inlet of the bidirectional pump 110 and the second port 116b operates as the outlet of the bidirectional pump 110, the bidirectional pump 110 draws in hydraulic fluid from the first distribution line section 133a through the first port 116a and discharges the hydraulic fluid into the second distribution line section 133b through the second port 116b. In the following example: when the second port 116b operates as the inlet of the bidirectional pump 110 and the first port 116a operates as the outlet of the bidirectional pump 110, the bidirectional pump 110 draws in hydraulic fluid from the second distribution line section 133b through the second port 116b and discharges the hydraulic fluid into the first distribution line section 133a through the first port 116a.

[0051] The suspension system 100 also includes a left front axle connection line 140a, a right front axle connection line 140b, a left rear axle connection line 140c, and a right rear axle connection line 140d. The left front axle connection line 140a extends between the first hydraulic line 132a of the first hydraulic circuit 120a and the second hydraulic line 132b of the second hydraulic circuit 120b, near the left front shock absorber 102a, and achieves fluid connection between the two. The right front axle connection line 140b extends between the first hydraulic line 132a of the first hydraulic circuit 120a and the second hydraulic line 132b of the second hydraulic circuit 120b, near the right front shock absorber 102b, and achieves fluid connection between the two. The left rear axle pipe 140c extends from the left rear shock absorber 102c between the third hydraulic line 132c of the third hydraulic circuit 120c and the fourth hydraulic line 132d of the fourth hydraulic circuit 120d, achieving a fluid connection between the two. Similarly, the right rear axle pipe 140d extends from the right rear shock absorber 102d between the third hydraulic line 132c of the third hydraulic circuit 120c and the fourth hydraulic line 132d of the fourth hydraulic circuit 120d, achieving a fluid connection between the two. In the example shown, all hydraulic lines are made of flexible tubing (such as hydraulic hoses), but it should be understood that other conduit structures and / or fluid channels may also be used.

[0052] The first hydraulic circuit 120a includes a first pair of variable flow control valves 160 and 162, respectively disposed at both ends of the first hydraulic line 132a, and configured to regulate the fluid flow between the first hydraulic circuit 120a and the first compression chamber 126a of the left front shock absorber 102a, and between the first hydraulic circuit 120a and the second rebound chamber 128b of the right front shock absorber 102b. Similarly, the second hydraulic circuit 120b includes a second pair of variable flow control valves 164 and 166, used to regulate the fluid flow between the second hydraulic circuit 120b and the first rebound chamber 128a of the left front shock absorber 102a, and between the first hydraulic circuit 120a and the second compression chamber 126b of the right front shock absorber 102b. The third hydraulic circuit 120c includes a third pair of variable flow control valves 168 and 170, respectively disposed at both ends of the third hydraulic line 132c, for regulating the fluid flow between the third hydraulic circuit 120c and the third compression chamber 126c of the left rear shock absorber 102c, and between the third hydraulic circuit 120c and the fourth rebound chamber 128d of the right rear shock absorber 102d. Finally, the fourth hydraulic circuit 120d includes a fourth pair of variable flow control valves 172 and 174, for regulating the fluid flow between the fourth hydraulic circuit 120d and the third rebound chamber 128c of the left rear shock absorber 102c, and between the fourth hydraulic circuit 120d and the fourth compression chamber 126d of the right rear shock absorber 102d. Variable flow control valves 160, 162, 164, 166, 168, 170, 172, and 174 can be passive / spring-biased valves (such as spring-disc valve assemblies) or active valves (such as electromechanical valves). They change / adjust the rebound damping rate and compression damping rate by controlling the fluid flow into and out of the compression chambers 126a, 126b, 126c, and 126d and the rebound chambers 128a, 128b, 128c, and 128d of the dampers 102a, 102b, 102c, and 102d. As a non-limiting example, variable flow control valves 160, 162, 164, 166, 168, 170, 172, and 174 can be electromechanical valves combining passive spring-disc elements and solenoid coils. The electromagnetic coils of the variable flow control valves 160, 162, 164, 166, 168, 170, 172, and 174 can be electrically connected to and driven by the controller 180, thereby changing the damping characteristics of the shock absorbers 102a, 102b, 102c, and 102d (e.g., making the ride softer or stiffer).

[0053] The left front accumulator 142a is fluidly connected to the first hydraulic line 132a, enabling it to regulate the fluid pressure within the first hydraulic circuit 120a. The right front accumulator 142b is fluidly connected to the second hydraulic line 132b, enabling it to regulate the fluid pressure within the second hydraulic circuit 120b. The left rear accumulator 142c is fluidly connected to the third hydraulic line 132c, enabling it to regulate the fluid pressure within the third hydraulic circuit 120c. The right rear accumulator 142d is fluidly connected to the fourth hydraulic line 132d, enabling it to regulate the fluid pressure within the fourth hydraulic circuit 120d. Accumulators 142a, 142b, 142c, and 142d all have variable fluid volumes, which change with the fluid pressure in hydraulic circuits 120a, 120b, 120c, and 120d. It should be noted that accumulators 142a, 142b, 142c, and 142d can adopt various different structural forms. For example (but not limited to this), accumulators 142a, 142b, 142c, and 142d can include an energy storage chamber and a pressurized gas chamber separated by a floating piston, a flexible diaphragm, or a bellows.

[0054] The suspension system 100 also includes seven electromechanical shut-off (i.e., on / off) valves 144a, 144b, 144c, 144d, 145a, 145b, and 146. The left front shut-off valve 144a is located in the left front axle line 140a, the right front shut-off valve 144b is located in the right front axle line 140b, the left rear shut-off valve 144c is located in the left rear axle line 140c, and the right rear shut-off valve 144d is located in the right rear axle line 140d. The first distribution line shut-off valve 145a is located in the first distribution line section 133a of the fluid distribution line 131, between the first longitudinal hydraulic line 130a and the bidirectional pump 110; the second distribution line shut-off valve 145b is located in the second distribution line section 133b of the fluid distribution line 131, between the second longitudinal hydraulic line 130b and the bidirectional pump 110. The reservoir shut-off valve 146 is located within the reservoir pipeline 114, between the fluid distribution pipeline 131 and the hydraulic fluid reservoir 112. In the illustrated example, shut-off valves 144a, 144b, 144c, 144d, 145a, 145b, and 146 are all semi-active electromechanical valves. Their structure combines a passive spring disc element with a solenoid coil, and the solenoid coil drives the valve to switch between open and closed positions.

[0055] When the first and second distribution line shut-off valves 145a and 145b are both open and the reservoir shut-off valve 146 is closed, the bidirectional pump 110 can operate to draw hydraulic fluid from the first longitudinal hydraulic line 130a (and then from the first and third hydraulic circuits 120a and 120c), and deliver it to the second longitudinal hydraulic line 130b, and then to the second and fourth hydraulic circuits 120b and 120d; and vice versa (delivered from the second longitudinal hydraulic line 130b, and then from the second and fourth hydraulic circuits 120b and 120d to the first longitudinal hydraulic line 130a, and then to the first and third hydraulic circuits 120a and 120c). When the first distribution line shut-off valve 145a is closed and both the second distribution line shut-off valve 145b and the reservoir shut-off valve 146 are open, the bidirectional pump 110 can operate to pump hydraulic fluid from the hydraulic fluid reservoir 112 into the second longitudinal hydraulic line 130b, or from the second longitudinal hydraulic line 130b back to the hydraulic fluid reservoir 112. If all shut-off valves 144a-144d are open, hydraulic fluid can flow through the bridge pipes 140a-140d, ultimately achieving the adjustment of the static fluid pressure of all four hydraulic circuits 120a-120d.

[0056] The bidirectional pump 110 and shut-off valves 144a, 144b, 144c, 144d, 145a, 145b, and 146 are all electrically connected to the controller 180. This controller is configured to activate the bidirectional pump 110 (i.e., open in either the forward or reverse direction) in response to various input signals, including fluid pressure, and to individually control the opening and closing of shut-off valves 144a, 144b, 144c, 144d, 145a, 145b, and 146. The anti-pitch and anti-roll functions of the suspension system 100 will be described in detail below; however, from... Figure 2 It is understood that the fluid pressure of hydraulic circuits 120a, 120b, 120c, and 120d can be adjusted by operating the bidirectional pump 110, thereby dynamically adjusting the pitch and roll stiffness of the suspension system 100, and thus changing the degree of vehicle tilt (i.e., pitch) or roll (i.e., body roll). Therefore, the suspension system 100 described herein can both enhance and completely replace mechanical stabilizer bars / anti-roll bars. Such mechanical systems require a relatively straight and unobstructed path between each front shock absorber 102a, 102b and each rear shock absorber 102c, 102d. Therefore, the suspension system 100 disclosed herein has a layout advantage because each shock absorber 102a, 102b, 102c, and 102d only needs to be hydraulically connected to each other and connected to the bidirectional pump 110.

[0057] As shown in the figure, the suspension system 100 can passively or actively control three main suspension movements by changing or adjusting the vehicle's roll and / or pitch stiffness: tilting to one side or the other during cornering (i.e., roll), pitching forward during braking (i.e., brake dive), and pitching backward during acceleration (i.e., rear end squat). The response mechanisms of the suspension system 100 to each of these conditions will be explained below.

[0058] Figure 3 The suspension system 100 is shown in a first comfort operating mode. When passive or active roll / pitch stiffness is not required, the controller 180 activates the first comfort operating mode by opening the left front shut-off valve 144a, right front shut-off valve 144b, left rear shut-off valve 144c, and right rear shut-off valve 144d, while simultaneously closing the first / second distribution line shut-off valves 145a and 145b and the reservoir shut-off valve 146. In the first comfort operating mode, the bidirectional pump 110 is de-energized to maintain substantially equal static pressures in all four hydraulic circuits 120a, 120b, 120c, and 120d. Therefore, in this first comfort operating mode, fluid flow is allowed through valves 144a, 144b, 144c, and 144d, thereby improving the ride comfort of the suspension system 100 and reducing or eliminating undesirable suspension movements caused by hydraulic coupling between one shock absorber and another (e.g., the compression of one shock absorber triggering movement and / or damping changes in another). For example, when the left front comfort valve 144a is open and the left front shock absorber 102a undergoes its compression stroke due to impact from the front wheel, fluid may flow out from the first compression chamber 126a of the left front shock absorber 102a, enter the first hydraulic line 132a, and then flow through the left front axle connector 140a and the left front comfort valve 144a from the first hydraulic line 132a to the second hydraulic line 132b, finally flowing into the first rebound chamber 128a of the left front shock absorber 102a. Therefore, fluid can flow from the first compression chamber 126a to the first rebound chamber 128a of the left front shock absorber 102a, with the only limitation being the variable control valves 160 and 164 (if present). Thus, in comfort mode, effective decoupling is achieved between the shock absorbers 102a, 102b, 102c, and 102d, thereby improving ride comfort.

[0059] Figure 4The suspension system 100 in a second comfort operating mode is shown. This mode is substantially similar to the first comfort operating mode, except that in the second comfort operating mode, the first and second distribution line shut-off valves 145a and 145b are open, allowing hydraulic fluid to flow through the fluid distribution line 131. The controller 180 activates the second comfort operating mode by opening the left front shut-off valve 144a, right front shut-off valve 144b, left rear shut-off valve 144c, right rear shut-off valve 144d, and the first and second distribution line shut-off valves 145a and 145b, while simultaneously closing the reservoir shut-off valve 146. In the second comfort operating mode, the bidirectional pump 110 is in an idling state (i.e., the bidirectional pump 110 is de-energized, but fluid is still allowed to pass through it). In the example where the bidirectional pump 110 includes an impeller, the impeller of the bidirectional pump is freely rotating and has inertia in the second comfort operating mode, thereby providing additional damping for pressure / flow disturbances in the suspension system 100. In other words, in the second comfort operating mode, pressure / flow disturbances can flow from the first longitudinal hydraulic line 130a to the second longitudinal hydraulic line 130b, or from the second longitudinal hydraulic line 130b to the first longitudinal hydraulic line 130a, via the fluid distribution line 131 and the bidirectional pump 110. This larger / wider network of hydraulic lines / conduits, with its greater fluid volume, inertial resistance, and / or flow restriction, helps to attenuate pressure / flow disturbances at specific frequencies, thereby reducing the impact of single-impact events caused by hydraulic coupling on the other shock absorbers 102a-102d in the suspension system 100.

[0060] Figure 5 The suspension system 100 in passive roll control mode is shown. The controller 180 activates the passive roll control mode by closing the left front shut-off valve 144a, right front shut-off valve 144b, left rear shut-off valve 144c, right rear shut-off valve 144d, first and second distribution line shut-off valves 145a and 145b, and reservoir shut-off valve 146. Furthermore, the bidirectional pump 110 is deactivated in passive roll control mode.

[0061] When the vehicle makes a left turn, the sprung mass inertia of the body 103 tends to cause the vehicle to lean to the right on the outside of the turn, thereby compressing the right front shock absorber 102b and the right rear shock absorber 102d. When this happens, fluid flows out from the second compression chamber 126b of the right front shock absorber 102b and the fourth compression chamber 126d of the right rear shock absorber 102d, and enters the second and fourth hydraulic lines 132b and 132d. As the vehicle's weight shifts to the right, the left front shock absorber 102a and the left rear shock absorber 102c begin to extend. This causes fluid to flow out of the first rebound chamber 128a of the left front shock absorber 102a and the third rebound chamber 128c of the left rear shock absorber 102c, entering the second and fourth hydraulic lines 132b and 132d. This further increases the pressure in the second and fourth hydraulic lines 132b and 132d, thereby increasing the pressure in the second compression chamber 126b of the right front shock absorber 102b and the fourth compression chamber 126d of the right rear shock absorber 102d. Consequently, the right front shock absorber 102b and the right rear shock absorber 102d become more difficult to compress. This counteracts the inertial / roll moment generated when the sprung mass of the vehicle body 103 attempts to tilt or lean to the right.

[0062] When the vehicle makes a right turn, the sprung mass inertia of the vehicle body 103 causes the vehicle to lean to the left on the outside of the turn, thereby compressing the left front shock absorber 102a and the left rear shock absorber 102c. When this happens, fluid flows out from the first compression chamber 126a of the left front shock absorber 102a and the third compression chamber 126c of the left rear shock absorber 102c, and enters the first hydraulic line 132a and the third hydraulic line 132c. As the vehicle's weight shifts to the left side, the right front shock absorber 102b and the right rear shock absorber 102d begin to extend. This causes fluid to flow out of the second rebound chamber 128b of the right front shock absorber 102b and the fourth rebound chamber 128d of the right rear shock absorber 102d, entering the first and third hydraulic lines 132a and 132c. This further increases the pressure in the first and third hydraulic lines 132a and 132c, thereby increasing the pressure in the first compression chamber 126a of the left front shock absorber 102a and the third compression chamber 126c of the left rear shock absorber 102c. Consequently, the left front shock absorber 102a and the left rear shock absorber 102c become more difficult to compress. This counteracts the inertial / roll moment generated when the sprung mass of the vehicle body 103 attempts to tilt or lean to the left.

[0063] Figure 6The suspension system 100 in active roll control mode is shown. When the vehicle makes a left turn, the sprung mass inertia of the vehicle body 103 causes the vehicle to tilt to the right on the outside of the turn, thereby compressing the right front shock absorber 102b and the right rear shock absorber 102d. At this time, fluid flows out from the second compression chamber 126b of the right front shock absorber 102b and the fourth compression chamber 126d of the right rear shock absorber 102d, and enters the second and fourth hydraulic lines 132b and 132d. As the vehicle weight shifts to the right, the left front shock absorber 102a and the left rear shock absorber 102c begin to extend, causing fluid to flow out from the first rebound chamber 128a of the left front shock absorber 102a and the third rebound chamber 128c of the left rear shock absorber 102c, and enter the second and fourth hydraulic lines 132b and 132d. At this time, the controller 180 activates the active tilt control operation mode by closing the left front shut-off valve 144a, right front shut-off valve 144b, left rear shut-off valve 144c, right rear shut-off valve 144d, and reservoir shut-off valve 146, while simultaneously opening the first and second distribution line shut-off valves 145a and 145b, and starting the bidirectional pump 110 to pump hydraulic fluid along the first direction 115a from the first distribution line section 133a (i.e., from the first longitudinal hydraulic line 130a) into the second distribution line section 133b (i.e., into the second longitudinal hydraulic line 130b). In this example, the second port 116b operates as the outlet of the bidirectional pump 110, and the first port 116a operates as the inlet of the bidirectional pump 110. Therefore, the bidirectional pump 110 draws in hydraulic fluid from the first distribution line section 133a through the first port 116a and discharges hydraulic fluid to the second distribution line section 133b through the second port 116b. During this process, the operation of the bidirectional pump 110 increases the fluid pressure in the second longitudinal hydraulic line 130b, which further increases the pressure in the second hydraulic circuit 120b (and consequently the second compression chamber 126b of the right front shock absorber 102b) and the fourth hydraulic circuit 120d (and consequently the fourth hydraulic circuit 126d of the right rear shock absorber 102d), ultimately making the right front shock absorber 102b and the right rear shock absorber 102d more difficult to compress. This counteracts the inertial moment / roll moment generated when the sprung mass of the vehicle body 103 attempts to tilt or lean to the right during a left turn.

[0064] When the vehicle makes a right turn, the sprung mass inertia of the vehicle body 103 causes the vehicle to lean to the left on the outside of the turn, thereby compressing the left front shock absorber 102a and the left rear shock absorber 102c. At this time, fluid flows out from the first compression chamber 126a of the left front shock absorber 102a and the third compression chamber 126c of the left rear shock absorber 102c, and enters the first hydraulic line 132a and the third hydraulic line 132c. As the weight of the vehicle body is transferred to the left side, the right front shock absorber 102b and the right rear shock absorber 102d begin to extend, causing fluid to flow out from the second rebound chamber 128b of the right front shock absorber 102b and the fourth rebound chamber 128d of the right rear shock absorber 102d, and enter the first and third hydraulic lines 132a and 132c. At this time, the controller 180 activates the active tilt control operation mode by closing the left front shut-off valve 144a, right front shut-off valve 144b, left rear shut-off valve 144c, right rear shut-off valve 144d, and reservoir shut-off valve 146, while simultaneously opening the first and second distribution line shut-off valves 145a and 145b, and starting the bidirectional pump 110, causing hydraulic fluid to be pumped from the second distribution line section 133b (i.e., the second longitudinal hydraulic line 130b) into the first distribution line section 133a (i.e., the first longitudinal hydraulic line 130a) along the second direction 115b. According to this example, the first port 116a operates as the outlet of the bidirectional pump 110, and the second port 116b operates as the inlet of the bidirectional pump 110. Therefore, the bidirectional pump 110 draws in hydraulic fluid from the second distribution line section 133b through the second port 116b and discharges hydraulic fluid into the first distribution line section 133a through the first port 116a. During this process, the operation of the bidirectional pump 110 increases the pressure in the first longitudinal hydraulic line 130a, which in turn increases the pressure in the first hydraulic circuit 120a (which in turn increases the pressure in the first compression chamber 126a of the left front shock absorber 102a) and the third hydraulic circuit 120c (which in turn increases the pressure in the third compression chamber 126c of the left rear shock absorber 102c), making the left front shock absorber 102a and the left rear shock absorber 102c more difficult to compress. This counteracts the inertial moment / roll moment generated when the sprung mass of the vehicle body 103 attempts to tilt or roll to the left during a right turn.

[0065] Figure 7The suspension system 100 is shown when the controller 180 initiates the pressure control operation mode. To increase the fluid pressure in the hydraulic circuits 120a, 120b, 120c, and 120d of the suspension system 100, the controller 180 activates the bidirectional pump 110 to draw hydraulic fluid from the hydraulic fluid reservoir 112 along the first direction 115a via the reservoir line 114, and pump it into the second longitudinal hydraulic line 130b through the second distribution line section 133b. In this example, the left front shut-off valve 144a, right front shut-off valve 144b, left rear shut-off valve 144c, and right rear shut-off valve 144d are all open, the first distribution line shut-off valve 145a is closed, and the second distribution line shut-off valve 145b and the reservoir shut-off valve 146 are both open. The first port 116a operates as the inlet of the bidirectional pump 110, and the second port 116b operates as the outlet of the bidirectional pump 110. Therefore, the bidirectional pump 110 draws in hydraulic fluid from the first distribution line section 133a through the first port 116a and discharges the hydraulic fluid into the second distribution line section 133b through the second port 116b. Since the left front shut-off valve 144a, right front shut-off valve 144b, left rear shut-off valve 144c, and right rear shut-off valve 144d are all open, the static pressure of all hydraulic circuits 120a, 120b, 120c, and 120d increases accordingly.

[0066] To reduce the fluid pressure in the hydraulic circuits 120a, 120b, 120c, and 120d of the suspension system 100, the controller 180 activates the bidirectional pump 110 to draw hydraulic fluid from the second longitudinal hydraulic line 130b along the second direction 115b via the second distribution line section 133b, and pumps it into the hydraulic fluid reservoir 112 through the reservoir line 114. In this example, the left front shut-off valve 144a, right front shut-off valve 144b, left rear shut-off valve 144c, and right rear shut-off valve 144d are all open, the first distribution line shut-off valve 145a is closed, while the second distribution line shut-off valve 145b and the reservoir shut-off valve 146 are both open. The second port 116b operates as the inlet of the bidirectional pump 110, and the first port 116a operates as the outlet of the bidirectional pump 110. Therefore, the bidirectional pump 110 draws in hydraulic fluid from the second distribution line section 133b through the second port 116b and discharges the hydraulic fluid into the first distribution line section 133a through the first port 116a. Since the left front shut-off valve 144a, right front shut-off valve 144b, left rear shut-off valve 144c, and right rear shut-off valve 144d are all open, the static pressure of all hydraulic circuits 120a, 120b, 120c, and 120d decreases accordingly.

[0067] Figure 8 Another suspension system 200 is shown, which is similar to Figures 2 to 7 The suspension system 100 shown shares multiple identical components, but Figures 2 to 7 The bidirectional pump 110 in the middle has been adjusted in installation position and in Figure 8 A dual-cavity ball screw mechanism 252 has been added to the suspension system 200 shown. Based on the above modifications, Figure 8 The suspension system 200 shown has been cancelled. Figures 2 to 7 The first and second distribution line shut-off valves 145a and 145b are described below. To avoid repeating the previous explanation, the following text will focus on... Figure 8 Compared to Figures 2-7 The structure and functionality of newly added or changed components. Note: Figure 8 The reference numerals for the components in the drawings use the "200" series numbering (such as 200, 202a, 204a, etc.), but the reference numerals for the remaining basic drawings are the same as those in the drawings. Figure 2-7 The corresponding components remain consistent. Therefore, unless otherwise stated, the above descriptions of components 100, 102a, and 104a also apply. Figure 8 Components such as 200, 202a, and 204a are included.

[0068] exist Figure 8 In this embodiment, the first longitudinal hydraulic line 230a is connected to the hydraulic fluid storage tank 212 via the storage tank line 214. In this embodiment, the bidirectional pump 210 is arranged along and connected in series with the storage tank line 214, and the storage tank shut-off valve 246 is located on the storage tank line 214, between the first longitudinal hydraulic line 230a and the bidirectional pump 210. The bidirectional pump 210 can operate in both directions (i.e., pump fluid), enabling the pumping of fluid into or out of the first longitudinal hydraulic line 230a. Therefore, when the left front shut-off valve 244a, right front shut-off valve 244b, left rear shut-off valve 244c, right rear shut-off valve 244d, and storage tank shut-off valve 246 are all open, the bidirectional pump 210 can increase or decrease the fluid pressure in all hydraulic circuits 220a-220d (i.e., increase or decrease the system pressure).

[0069] As its name suggests, the dual-chamber ball screw mechanism 252 has a first variable volume chamber 254a and a second variable volume chamber 254b at opposite ends of the cylinder housing 256. The first variable volume chamber 254a is in fluid communication with the first distribution line 233a (and consequently with the first longitudinal hydraulic line 230a), while the second variable volume chamber 254b is in fluid communication with the second distribution line 233b (and consequently with the second longitudinal hydraulic line 230b). The first and second variable volume chambers 254a and 254b are separated by a pair of driven pistons 258a and 258b, which are connected to and move synchronously with the threaded rod 260. The dual-cavity ball screw mechanism 252 also includes a motor 262, which is threadedly connected to a threaded rod 260, thereby driving the threaded rod 260 to move the driven piston pairs 258a and 258b within the cylinder housing 256 along a first direction 215a and a second direction 215b. The first direction 215a and the second direction 215b are longitudinally opposite directions.

[0070] When the motor 262 drives the threaded rod 260 to move a pair of driven pistons 258a and 258b along the first direction 215a, the volume of the first variable volume chamber 254a increases, while the volume of the second variable volume chamber 254b decreases. This causes hydraulic fluid in the first distribution pipe section 233a to flow into the first variable volume chamber 254a, while hydraulic fluid in the second variable volume chamber 254b flows out to the second distribution pipe 233b, thereby reducing the fluid pressure in the first longitudinal hydraulic line 230a (and thus reducing the fluid pressure in the first and third hydraulic circuits 220a and 220c), while increasing the fluid pressure in the second longitudinal hydraulic line 230b (and thus increasing the fluid pressure in the second and fourth hydraulic circuits 220b and 220d). When the motor 262 drives the threaded rod 260 to move a pair of driven pistons 258a and 258b along the second direction 215b, the volume of the first variable volume chamber 254a decreases, while the volume of the second variable volume chamber 254b increases. This causes the hydraulic fluid in the first variable volume chamber 254a to flow out to the first distribution line 233a, while the hydraulic fluid in the second distribution line 233b flows into the second variable volume chamber 254b, thereby increasing the fluid pressure in the first longitudinal hydraulic line 230a (and thus increasing the fluid pressure in the first and third hydraulic circuits 220a and 220c), while decreasing the fluid pressure in the second longitudinal hydraulic line 230b (and thus decreasing the fluid pressure in the second and fourth hydraulic circuits 220b and 220d).

[0071] Motor 262 is electrically connected to and controlled by controller 280. The direction of rotation of the motor (clockwise or counterclockwise) depends on the polarity of the current supplied by controller 280. This, in turn, drives the threaded rod 260 to move linearly / longitudinally in the opposite direction. Therefore, controller 280 can achieve [the desired effect]. Figures 3 to 7The same operating mode.

[0072] Figures 9 to 17 Another suspension system 300 is shown, which is similar to Figures 2 to 7 The suspension system 100 shown shares several identical components, but adds three additional bidirectional pumps 310a, 310b, and 310c. To avoid repeating the previous descriptions, the following section will focus on... Figures 9 to 17 Compared to Figures 2 to 7 The diagram shows newly added or different structures and functions. Note that... Figures 9 to 17 The reference numerals for components in the drawings use the "300" series (such as 300, 302a, 304a, etc.), while the reference numerals for other basic components are the same as those in the drawings. Figures 2 to 7 The corresponding components remain consistent. Therefore, unless otherwise stated, the above descriptions of components 100, 102a, and 104a also apply. Figures 9 to 17 Components such as 300, 302a, and 304a are included.

[0073] The suspension system 300 includes a first bidirectional pump 310a, which is arranged along and connected in series with a fluid distribution line 331, which extends between and interconnects a first longitudinal hydraulic line 330a and a second longitudinal hydraulic line 330b. The suspension system 300 also includes a second bidirectional pump 310b and a third bidirectional pump 310c, whereby the second bidirectional pump 310b is arranged along and connected in series with the first longitudinal hydraulic line 330a, and the third bidirectional pump 310c is arranged along and connected in series with the second longitudinal hydraulic line 330b. The fluid distribution line 331 includes a first distribution line section 333a and a second distribution line section 333b. A first distribution line segment 333a extends between and fluidly connects the first longitudinal hydraulic line 330a and the first port 316a of the first bidirectional pump 310a. A second distribution line segment 333b extends between and fluidly connects the second longitudinal hydraulic line 330b and the second port 316b of the first bidirectional pump 310a. The first longitudinal hydraulic line 330a includes a first hydraulic line segment 334a and a second hydraulic line segment 334b. The first hydraulic line segment 334a extends between and fluidly connects the first hydraulic line 332a and the third port 316c of the second bidirectional pump 310b. The second hydraulic line segment 334b ​​extends between and fluidly connects the third hydraulic line 332c and the fourth port 316b of the second bidirectional pump 310b. The second longitudinal hydraulic line 330b includes a third hydraulic line segment 334c and a fourth hydraulic line segment 334d. The third hydraulic line segment 334c extends between the second hydraulic line 332b and the fifth port 316e on the third bidirectional pump 310b, fluidly connecting the two. The fourth hydraulic line segment 334d extends between the fourth hydraulic line 332d and the sixth port 316f on the third bidirectional pump 310c, fluidly connecting the two. Each bidirectional pump 310a, 310b, 310c can operate in two opposite directions (i.e., pump fluid) depending on the polarity of the current supplied to it.

[0074] The first port 316a of the first bidirectional pump 310a can function as either an inlet or an outlet depending on the pump's operating direction, and the same applies to its second port 316b. Therefore, the first bidirectional pump 310a can pump hydraulic fluid from the first distribution section 333a of the fluid distribution line 331 (and subsequently from the first longitudinal hydraulic line 330a or the reservoir line 314) to the second distribution section 333b of the fluid distribution line 331 (and subsequently to the second longitudinal hydraulic line 330b). The first bidirectional pump 310a can also operate in the reverse direction, pumping hydraulic fluid from the second distribution section 333b of the fluid distribution line 331 (and subsequently from the second longitudinal hydraulic line 330b) to the first distribution section 333a of the fluid distribution line 331 (and subsequently to the first longitudinal hydraulic line 330a or the reservoir line 314).

[0075] In the operating mode where the first port 316a serves as the inlet of the first bidirectional pump 310a and the second port 316b serves as its outlet, the first bidirectional pump 310a draws in hydraulic fluid from the first distribution pipeline section 333a through the first port 316a and discharges the hydraulic fluid into the second distribution pipeline section 333b through the second port 316b. In the operating mode where the second port 316b serves as the inlet of the first bidirectional pump 310a and the first port 316a serves as the outlet, the first bidirectional pump 310a draws in hydraulic fluid from the second distribution pipeline section 333b through the second port 316b and discharges the hydraulic fluid into the first distribution pipeline section 333a through the first port 316a.

[0076] The third port 316c of the second bidirectional pump 310b can act as either an inlet or an outlet depending on the pump's operating direction, and the same applies to its fourth port 316d. Therefore, the second bidirectional pump 310b can achieve the following two pumping states through operation: first, along the third direction 315c, it draws hydraulic fluid from the second section 334b ​​of the first longitudinal hydraulic line 330a (and subsequently from the third hydraulic circuit 320c), and pumps it to the first section 334a of the first longitudinal hydraulic line 330a (and subsequently to the first hydraulic circuit 320a); second, along the fourth direction 315b, it draws hydraulic fluid from the first section 334a of the first longitudinal hydraulic line 330a (and subsequently from the first hydraulic circuit 320a), and pumps it to the second section 334b ​​of the second longitudinal hydraulic line 330a (and subsequently to the third hydraulic circuit 320c). In a configuration where the fourth port 316d serves as the inlet of the second bidirectional pump 310b and the third port 316c serves as its outlet, the second bidirectional pump 310b draws in hydraulic fluid from the second hydraulic line section 334b ​​through the fourth port 316d and discharges the hydraulic fluid into the first hydraulic line section 334a through the third port 316c. In a configuration where the third port 316c serves as the inlet of the second bidirectional pump 310b and the fourth port 316d serves as its outlet, the second bidirectional pump 310b draws in hydraulic fluid from the first hydraulic line section 334a through the third port 316c and discharges the hydraulic fluid into the second hydraulic line section 334b ​​through the fourth port 316d.

[0077] The fifth port 316e of the third bidirectional pump 310c can function as either an inlet or an outlet depending on the pump's operating direction, and the same applies to its sixth port 316f. Therefore, the third bidirectional pump 310c can achieve the following two pumping states: first, pumping hydraulic fluid from the fourth hydraulic line segment 334d of the second longitudinal hydraulic line 330b (and subsequently from the fourth hydraulic circuit 320d) to the third hydraulic line segment 334c of the second longitudinal hydraulic line 330b (and subsequently to the second hydraulic circuit 320b) along the fifth direction 315e; second, pumping hydraulic fluid from the third hydraulic line segment 334c of the second longitudinal hydraulic line 330b (and subsequently from the second hydraulic circuit 320b) to the fourth hydraulic line segment 334d of the second longitudinal hydraulic line 330b (and subsequently to the fourth hydraulic circuit 320d) along the sixth direction 315f. With port 316f serving as the inlet of the third bidirectional pump 310c and port 316e serving as its outlet, the third bidirectional pump 310c draws in hydraulic fluid from the fourth hydraulic line section 334d through port 316f and discharges the hydraulic fluid into the third hydraulic line section 334c through port 316e. Conversely, with port 316e serving as the inlet of the third bidirectional pump 310c and port 316f serving as its outlet, the third bidirectional pump 310c draws in hydraulic fluid from the third hydraulic line section 334c through port 316e and discharges the hydraulic fluid into the fourth hydraulic line section 334d through port 316f.

[0078] Similarly, the illustrated suspension system 300 can passively or actively control three main suspension movements by changing or adjusting the vehicle's roll and / or pitch stiffness: tilting to one side or the other during cornering (i.e., roll), pitching forward during braking (i.e., brake dive), and pitching backward during acceleration (i.e., rear-end sag). The response mechanisms of the suspension system 300 to these three operating conditions will be described below.

[0079] Figure 10The suspension system 300 in the first comfort operating mode is shown. When passive or active roll and / or pitch stiffness is not required, the controller 380 can activate the first comfort operating mode by opening the left front shut-off valve 344a, right front shut-off valve 344b, left rear shut-off valve 344c, and right rear shut-off valve 344d, while simultaneously closing the first and second distribution line shut-off valves 345a and 345b and the reservoir shut-off valve 346. In this mode, the first, second, and third bidirectional pumps 310a, 310b, and 310c are all de-energized to maintain essentially equal static pressure in the four hydraulic circuits 320a, 320b, 320c, and 320d. In the first comfort operating mode, fluid is allowed to flow through valves 344a, 344b, 344c, and 344d, thereby improving the ride comfort of the suspension system 300 and reducing or eliminating undesirable suspension movements caused by hydraulic coupling between one shock absorber and another within the system (e.g., one shock absorber compressing and causing movement and / or damping changes in another shock absorber). For example, when the left front comfort valve 344a is open and the left front shock absorber 302a undergoes its compression stroke due to front wheel impact, fluid may flow out from the first compression chamber 326a of the left front shock absorber 302a, enter the first hydraulic line 332a, and then flow from the first hydraulic line 332a into the second hydraulic line 332b through the left front axle line 340a and the left front comfort valve 344a, ultimately flowing into the first rebound chamber 328a of the left front shock absorber 302a. Therefore, fluid can flow from the first compression chamber 326a of the left front shock absorber 302a to the first rebound chamber 328a, with its flow limited only by variable control valves 360, 364 (if present). In the first comfort operating mode, the second and third bidirectional pumps 310b, 310c are in an idling state (i.e., the second and third bidirectional pumps 310b, 310c are de-energized, but fluid is still allowed to flow through them), thus ensuring that fluid can still flow through the first and second longitudinal hydraulic lines 330a, 330b. In the example of the second and third bidirectional pumps 310b, 310c containing impellers, the impellers can rotate freely and maintain inertia in this mode, thus providing additional damping for pressure / flow disturbances in the suspension system 300. Therefore, in the first comfort operating mode, shock absorbers 302a-302d are effectively decoupled from each other, thereby improving ride comfort.

[0080] Figure 11The suspension system 300 in a second comfort operating mode is shown. The second comfort operating mode is substantially similar to the first comfort operating mode, except that in the second comfort operating mode, the first and second distribution line shut-off valves 345a and 345b are open, allowing hydraulic fluid to flow through the fluid distribution line 331. The controller 380 activates the second comfort operating mode by opening the left front shut-off valve 344a, right front shut-off valve 344b, left rear shut-off valve 344c, right rear shut-off valve 344d, and the first and second distribution line shut-off valves 345a and 345b, while simultaneously closing the reservoir shut-off valve 346. In the second comfort operating mode, the first bidirectional pump 310a is also placed in an idling state (i.e., the first bidirectional pump 310a is de-energized, but fluid flow is still allowed through the pump). In an example where the first bidirectional pump 310a includes an impeller, the impeller of the first bidirectional pump is freely rotating and has inertia in the second comfort operating mode, thereby providing additional damping for pressure / flow disturbances in the suspension system 300. Therefore, in the second comfort operating mode, pressure / flow disturbances can flow not only through the second bidirectional pump 310b and the third bidirectional pump 310c, but also through the fluid distribution line 331 and the first bidirectional pump 310a, from the first longitudinal hydraulic line 330a to the second longitudinal hydraulic line 330b, or from the second longitudinal hydraulic line 330b to the first longitudinal hydraulic line 330a. This larger / wider hydraulic line network has greater fluid volume, inertial resistance, and / or flow restriction, which helps to attenuate pressure / flow disturbances at specific frequencies, thereby reducing the impact of single impact events caused by hydraulic coupling on other shock absorbers 302a-302d in the suspension system 300.

[0081] Figure 12 The suspension system 300 in passive roll control mode is shown. The controller 380 activates the passive roll control mode by closing the left front shut-off valve 344a, right front shut-off valve 344b, left rear shut-off valve 344c, right rear shut-off valve 344d, first and second distribution line shut-off valves 345a and 345b, and reservoir shut-off valve 346. In passive roll control mode, the first bidirectional pump 310a is deactivated, and the second and third bidirectional pumps 310b and 310c are de-energized and enter an idling state, allowing hydraulic fluid in the first and second longitudinal hydraulic lines 330a and 330b to flow through the second and third bidirectional pumps 310b and 310c.

[0082] When the vehicle makes a left turn, the sprung mass inertia of the body 103 tends to cause the vehicle to lean to the right on the outside of the turn, thereby compressing the right front shock absorber 302b and the right rear shock absorber 302d. When this happens, fluid flows out from the second compression chamber 326b of the right front shock absorber 302b and the fourth compression chamber 326d of the right rear shock absorber 302d, and enters the second and fourth hydraulic lines 332b and 332d. As the vehicle's weight shifts to the right, the left front shock absorber 302a and the left rear shock absorber 302c begin to extend. This causes fluid to flow out of the first rebound chamber 328a of the left front shock absorber 302a and the third rebound chamber 328c of the left rear shock absorber 302c, entering the second and fourth hydraulic lines 332b and 332d. This further increases the pressure in the second and fourth hydraulic lines 332b and 332d, thereby increasing the pressure in the second compression chamber 326b of the right front shock absorber 302b and the fourth compression chamber 326d of the right rear shock absorber 302d. Consequently, the right front shock absorber 302b and the right rear shock absorber 302d become more difficult to compress. This counteracts the inertial moment / roll moment generated when the sprung mass of the vehicle body 103 attempts to tilt or roll to the right.

[0083] When the vehicle makes a right turn, the sprung mass inertia of the vehicle body 103 causes the vehicle to lean to the left on the outside of the turn, thereby compressing the left front shock absorber 302a and the left rear shock absorber 302c. When this happens, fluid flows out from the first compression chamber 326a of the left front shock absorber 302a and the third compression chamber 326c of the left rear shock absorber 302c, and enters the first hydraulic line 332a and the third hydraulic line 332c. As the vehicle weight shifts to the left side, the right front shock absorber 302b and the right rear shock absorber 302d begin to extend. This causes fluid to flow out from the second rebound chamber 328b of the right front shock absorber 302b and the fourth rebound chamber 328d of the right rear shock absorber 302d, entering the first and third hydraulic lines 332a and 332c. This further increases the pressure in the first and third hydraulic lines 332a and 332c, thereby increasing the pressure in the first compression chamber 326a of the left front shock absorber 302a and the third compression chamber 326c of the left rear shock absorber 302c. Consequently, the left front shock absorber 302a and the left rear shock absorber 302c become more difficult to compress. This counteracts the inertial moment / roll moment generated when the sprung mass of the vehicle body 103 attempts to tilt or roll to the left.

[0084] Figure 13The suspension system 300 in active roll control mode is shown. When the vehicle makes a left turn, the sprung mass inertia of the vehicle body 103 causes the vehicle to tilt to the right on the outside of the turn, thereby compressing the right front shock absorber 302b and the right rear shock absorber 302d. At this time, fluid flows out from the second compression chamber 326b of the right front shock absorber 302b and the fourth compression chamber 326d of the right rear shock absorber 302d, and enters the second and fourth hydraulic lines 332b and 332d. As the vehicle weight shifts to the right, the left front shock absorber 302a and the left rear shock absorber 302c begin to extend, causing fluid to flow out from the first rebound chamber 328a of the left front shock absorber 302a and the third rebound chamber 328c of the left rear shock absorber 302c, and enter the second and fourth hydraulic lines 332b and 332d. At this time, the controller 380 activates the active tilt control operation mode in the following manner: closes the left front shut-off valve 344a, right front shut-off valve 344b, left rear shut-off valve 344c, right rear shut-off valve 344d and reservoir shut-off valve 346, and simultaneously opens the first and second distribution pipeline shut-off valves 345a and 345b, and starts the first bidirectional pump 310a to pump hydraulic fluid from the first distribution pipeline section 333a (i.e. from the first longitudinal hydraulic pipeline 330a) into the second distribution pipeline section 333b (i.e., pumped into the second longitudinal hydraulic pipeline 330b) along the first direction 315a.

[0085] In this example, the second port 316b operates as the outlet of the first bidirectional pump 310a, while the first port 316a operates as the inlet of the first bidirectional pump 310a. Therefore, the first bidirectional pump 310a draws hydraulic fluid from the first distribution line section 333a through the first port 316a and discharges hydraulic fluid into the second distribution line section 333b through the second port 316b. During this process, the operation of the first bidirectional pump 310a increases the fluid pressure in the second longitudinal hydraulic line 330b, which in turn increases the pressure in the second hydraulic circuit 320b (which in turn increases the pressure in the second compression chamber 326b of the right front shock absorber 302b) and the fourth hydraulic circuit 320d (which in turn increases the pressure in the fourth compression chamber 326d of the right rear shock absorber 303d), ultimately making the right front shock absorber 302b and the right rear shock absorber 302d more difficult to compress. This counteracts the inertial moment / roll moment generated when the sprung mass of the vehicle body 103 attempts to tilt or roll to the right during a left turn.

[0086] When the vehicle makes a right turn, the sprung mass inertia of the vehicle body 103 causes the vehicle to lean to the left on the outside of the turn, thereby compressing the left front shock absorber 302a and the left rear shock absorber 302c. At this time, fluid flows out from the first compression chamber 326a of the left front shock absorber 302a and the third compression chamber 326c of the left rear shock absorber 302c, and enters the first hydraulic line 332a and the third hydraulic line 332c. As the weight of the vehicle body is transferred to the left side, the right front shock absorber 302b and the right rear shock absorber 302d begin to extend, causing fluid to flow out from the second rebound chamber 328b of the right front shock absorber 302b and the fourth rebound chamber 328d of the right rear shock absorber 302d, and enter the first and third hydraulic lines 332a and 332c. At this time, the controller 380 activates the active tilt control operation mode by closing the left front shut-off valve 344a, right front shut-off valve 344b, left rear shut-off valve 344c, right rear shut-off valve 344d, and reservoir shut-off valve 346, while simultaneously opening the first and second distribution line shut-off valves 345a and 345b, and starting the first bidirectional pump 310a, which pumps hydraulic fluid along the second direction 315b from the second distribution line section 333b (i.e., the second longitudinal hydraulic line 330b) into the first distribution line section 333a (i.e., the first longitudinal hydraulic line 330a). According to this example, the first port 316a operates as the outlet of the first bidirectional pump 310a, and the second port 316b operates as the inlet of the first bidirectional pump 310a. Therefore, the first bidirectional pump 310a draws in hydraulic fluid from the second distribution line section 333b through the second port 316b and discharges hydraulic fluid to the first distribution line section 333a through the first port 316a. This causes the first bidirectional pump 310a to increase the fluid pressure in the first longitudinal hydraulic line 330a, thereby increasing the pressure in the first hydraulic circuit 320a (which in turn increases the pressure in the first compression chamber 326a of the left front shock absorber 302a) and the third hydraulic circuit 320c (which in turn increases the pressure in the third compression chamber 326c of the left rear shock absorber 302c). This makes the left front shock absorber 302a and the left rear shock absorber 302c more difficult to compress. This counteracts the inertial moment / roll moment generated when the sprung mass of the vehicle body 103 attempts to tilt or roll to the left during a right turn.

[0087] In the active tilt control operation mode, the second and third bidirectional pumps 310b and 310c are de-energized and idling, allowing the hydraulic fluid in the first and second longitudinal hydraulic lines 330a and 330b to flow through the second and third bidirectional pumps 310b and 310c.

[0088] Figure 14The suspension system 300 is shown in active roll moment distribution control mode. In this mode, the controller 380 performs one of two operations: first, it activates the second and third bidirectional pumps 310b and 310c to pump hydraulic fluid to the front axle along the third and fifth directions 315c and 315e, thereby increasing the fluid pressure in the first and second hydraulic circuits 320a and 320b; second, it activates the second and third bidirectional pumps 310b and 310c to pump hydraulic fluid to the rear axle along the fourth and sixth directions 315d and 315f, thereby increasing the fluid pressure in the third and fourth hydraulic circuits 320c and 320d. The suspension system 300 then utilizes the passive roll resistance mechanism described above, but counteracts body roll during cornering by placing the first and second hydraulic circuits 320a and 320b or the third and fourth hydraulic circuits 320c and 320d at higher static pressures. In the active tilt torque distribution control operation mode, the controller 380 closes the left front shut-off valve 344a, right front shut-off valve 344b, left rear shut-off valve 344c, right rear shut-off valve 344d, first and second distribution line shut-off valves 345a and 345b, and reservoir shut-off valve 346. Simultaneously, it starts the second and third bidirectional pumps 310b and 310c, causing them to pump hydraulic fluid along the third and fifth directions 315c and 315e or the fourth and sixth directions 315d and 315f. The first bidirectional pump 310a remains inactive in the active tilt torque distribution control operation mode.

[0089] When the controller 380 activates the second and third bidirectional pumps 310b and 310c to pump hydraulic fluid along the third and fifth directions 315c and 315e to the front axle to increase the fluid pressure in the first and second hydraulic circuits 320a and 320b, the third port 316c serves as the outlet of the second bidirectional pump 310b, and the fourth port 316d serves as the inlet of the second bidirectional pump 310b. Similarly, the fifth port 316e serves as the outlet of the third bidirectional pump 310c, and the sixth port 316f serves as the inlet of the third bidirectional pump 310c. Therefore, the second bidirectional pump 310b draws in hydraulic fluid from the second hydraulic line section 334b ​​through the fourth port 316d and discharges hydraulic fluid into the first hydraulic line section 334a through the third port 316c; the third bidirectional pump 310c draws in hydraulic fluid from the fourth hydraulic line section 334d through the sixth port 316f and discharges hydraulic fluid into the third hydraulic line section 334c through the fifth port 316e. Therefore, the second and third bidirectional pumps 310b and 310c increase the fluid pressure in the first and second hydraulic lines 332a and 332b by operation, thereby increasing the passive roll stiffness of the front axle and thus counteracting the inertial torque generated when the sprung mass of the vehicle body 103 attempts to tilt to the left or right during cornering.

[0090] When the controller 380 activates the second and third bidirectional pumps 310b and 310c to pump hydraulic fluid along the fourth and sixth directions 315d and 315f to the rear axle to increase the fluid pressure in the third and fourth hydraulic circuits 320c and 320d, the third port 316c serves as the inlet of the second bidirectional pump, and the fourth port 316d serves as the outlet of the second bidirectional pump 310b. Similarly, the fifth port 316e serves as the inlet of the third bidirectional pump 310c, and the sixth port 316f serves as the outlet of the third bidirectional pump 310c. Therefore, the second bidirectional pump 310b draws in hydraulic fluid from the first hydraulic line section 334a through the third port 316c and discharges hydraulic fluid into the second hydraulic line section 334b ​​through the fourth port 316d; the third bidirectional pump 310c draws in hydraulic fluid from the third hydraulic line section 334c through the fifth port 316e and discharges hydraulic fluid into the fourth hydraulic line section 334d through the sixth port 316f. Therefore, the second and third bidirectional pumps 310b and 310c increase the fluid pressure in the third and fourth hydraulic lines 332c and 332d by operation, thereby increasing the passive roll stiffness of the rear axle and thus counteracting the inertial torque generated when the sprung mass of the vehicle body 103 attempts to tilt to the left or right during cornering.

[0091] Figure 15 The suspension system 300 in pitch control operation mode is shown. During braking, the sprung mass inertia of the vehicle body 103 causes it to pitch or nod forward, compressing the left front shock absorber 302a and the right front shock absorber 302b. At this time, hydraulic fluid flows from the first compression chamber 326a of the left front shock absorber 302a into the first hydraulic line 332a, and from the second compression chamber 326b of the right front shock absorber 302b into the second hydraulic line 332b. As the vehicle weight shifts to the front, the left rear shock absorber 302c and the right rear shock absorber 302d begin to extend, causing fluid to flow from the third rebound chamber 328c of the left rear shock absorber 302c into the third hydraulic line 332c, and from the fourth rebound chamber 328d of the right rear shock absorber 302d into the fourth hydraulic line 332d. At this time, the controller 180 will initiate the pitch control operation mode in the following manner: close the left front shut-off valve 344a, right front shut-off valve 344b, left rear shut-off valve 344c, right rear shut-off valve 344d, first and second distribution line shut-off valves 345a and 345b, and reservoir shut-off valve 346; simultaneously start the second and third bidirectional pumps 310b and 310c, causing them to pump hydraulic fluid along the third and fifth directions 315c and 315e to increase the fluid pressure in the first and second hydraulic lines 332a and 332b. The first bidirectional pump 310a remains inactive in the active pitch control mode.

[0092] When the controller 380 activates the second and third bidirectional pumps 310b and 310c to pump hydraulic fluid to the front axle along the third and fifth directions 315c and 315e, thereby increasing the fluid pressure in the first and second hydraulic circuits 320a and 320b, the third port 316c serves as the outlet of the second bidirectional pump 310b, and the fourth port 316d serves as the inlet of the second bidirectional pump 310b. Similarly, the fifth port 316e serves as the outlet of the third bidirectional pump 310c, and the sixth port 316f serves as the inlet of the third bidirectional pump 310c. Therefore, the second bidirectional pump 310b draws in hydraulic fluid from the second hydraulic line section 334b ​​through the fourth port 316d and discharges the hydraulic fluid into the first hydraulic line section 334a through the third port 316c; the third bidirectional pump 310c draws in hydraulic fluid from the fourth hydraulic line section 334d through the sixth port 316f and discharges the hydraulic fluid into the third hydraulic line section 334c through the fifth port 316e. Therefore, the second and third bidirectional pumps 310b and 310c increase the fluid pressure in the first and second hydraulic lines 332a and 332b by operating, thereby increasing the pressure in the first compression chamber 126a of the left front shock absorber 102a and the second compression chamber 126b of the right front shock absorber 102b, making the left front shock absorber 102a and the right front shock absorber 102b more difficult to compress. This counteracts the inertia generated by the sprung mass of the vehicle body 103 attempting to lunge or nod forward during braking.

[0093] During acceleration, the sprung mass inertia of the vehicle body 103 causes it to pitch or sag (i.e., the rear of the vehicle to drop), thereby compressing the left rear shock absorber 302c and the right rear shock absorber 302d. At this time, fluid flows from the third compression chamber 326c of the left rear shock absorber 302c into the third hydraulic line 332c, and simultaneously from the fourth compression chamber 326d of the right rear shock absorber 302d into the fourth hydraulic line 332d. As the weight of the vehicle body is transferred to the rear, the left front shock absorber 302a and the right front shock absorber 302b begin to extend, causing fluid to flow from the first rebound chamber 328a of the left front shock absorber 302a into the second hydraulic line 332b, and simultaneously from the second rebound chamber 328b of the right front shock absorber 302b into the first hydraulic line 332a. At this time, the controller 380 activates the active pitch control operation mode in the following manner: closes the left front shut-off valve 344a, right front shut-off valve 344b, left rear shut-off valve 344c, right rear shut-off valve 344d, first and second distribution line shut-off valves 345a and 345b, and reservoir shut-off valve 346, and simultaneously starts the second and third bidirectional pumps 310b and 310c, so that they pump hydraulic fluid along the fourth and sixth directions 315d and 315f to increase the pressure in the third and fourth hydraulic lines 332c and 332d.

[0094] When the controller 380 activates the second and third bidirectional pumps 310b and 310c to pump hydraulic fluid to the rear axle along the fourth and sixth directions 315d and 315f to increase the fluid pressure in the third and fourth hydraulic circuits 320c and 320d, the third port 316c serves as the inlet of the second bidirectional pump 310b, and the fourth port 316d serves as the outlet of the second bidirectional pump 310b. Similarly, the fifth port 316e serves as the inlet of the third bidirectional pump 310c, and the sixth port 316f serves as the outlet of the third bidirectional pump 310c. Therefore, the second bidirectional pump 310b draws in hydraulic fluid from the first hydraulic line section 334a through the third port 316c and discharges hydraulic fluid into the second hydraulic line section 334b ​​through the fourth port 316d; the third bidirectional pump 310c draws in hydraulic fluid from the third hydraulic line section 334c through the fifth port 316e and discharges hydraulic fluid into the fourth hydraulic line section 334d through the sixth port 316f. Therefore, the second and third bidirectional pumps 310b and 310c operate to increase the fluid pressure in the third and fourth hydraulic lines 332c and 332d, thereby increasing the pressure in the third compression chamber 326c of the left rear shock absorber 302c and the fourth compression chamber 326d of the right rear shock absorber 302d, making the left rear shock absorber 302c and the right rear shock absorber 302d more difficult to compress. This counteracts the inertia generated when the sprung mass of the vehicle body 103 attempts to pitch or sit back (i.e., the rear of the vehicle sinks) during acceleration.

[0095] Figure 16 The diagram illustrates a suspension system 300 in torsion control operation mode, a mode that allows for greater or lesser range of motion during on-road or off-road maneuvers. The controller 380 initiates torsion control operation mode by closing the left front shut-off valve 344a, right front shut-off valve 344b, left rear shut-off valve 344c, right rear shut-off valve 344d, first and second distribution line shut-off valves 345a and 345b, and reservoir shut-off valve 346, while simultaneously activating the second and third bidirectional pumps 310b and 310c in opposite directions (e.g., as shown). Figure 16 Hydraulic fluid is pumped in the third and sixth directions (315c, 315f) or the fourth and fifth directions (315d, 315e). During the torsion control operation mode, the first bidirectional pump 310a remains inactive.

[0096] In the illustrated example, controller 380 has activated the second bidirectional pump 310b, causing it to pump hydraulic fluid along a third direction 315c from the second hydraulic line segment 334b ​​(i.e., from the third hydraulic circuit 320c) into the first hydraulic line segment 334a (i.e., the first hydraulic circuit 320a); simultaneously, it has activated the third bidirectional pump 310c, causing it to pump hydraulic fluid from the third hydraulic line segment 334c (i.e., from the second hydraulic circuit 320b) into the fourth hydraulic line segment 334d (i.e., the fourth hydraulic circuit 320d). In this example, the third port 316c operates as the outlet of the second bidirectional pump 310b, and the fourth port 316d operates as the inlet of the second bidirectional pump 310b. Conversely, the fifth port 316e operates as the inlet of the third bidirectional pump 310c, and the sixth port 316f operates as the outlet of the third bidirectional pump 310c. Therefore, the second bidirectional pump 310b draws in hydraulic fluid from the second hydraulic line section 334b ​​through the fourth port 316d and discharges the hydraulic fluid into the first hydraulic line section 334a through the third port 316c; the third bidirectional pump 310c draws in hydraulic fluid from the third hydraulic line section 334c through the fifth port 316e and discharges the hydraulic fluid into the fourth hydraulic line section 334d through the sixth port 316f. Thus, the second and third bidirectional pumps 310b and 310c can operate to increase the fluid pressure in the first and fourth hydraulic lines 332a and 332d, thereby increasing the pressure in the first compression chamber 326a of the left front shock absorber 302a and the fourth compression chamber 326d of the right rear shock absorber 302d, making the left front shock absorber 302a and the right rear shock absorber 302d more difficult to compress.

[0097] In another example, controller 380 may activate second bidirectional pump 310b to pump hydraulic fluid from first hydraulic line segment 334a (i.e., from first hydraulic circuit 320a) into second hydraulic line segment 334b ​​(i.e., into third hydraulic circuit 320c) along fourth direction 315d, while simultaneously activating third bidirectional pump 310c to pump hydraulic fluid from fourth hydraulic line segment 334d (i.e., from fourth hydraulic circuit 320d) into third hydraulic line segment 334c (and subsequently into second hydraulic circuit 320b) along fifth direction 315e. In this example, third port 316c operates as the inlet of second bidirectional pump 310b, and fourth port 316d operates as the outlet of second bidirectional pump 310b. Conversely, fifth port 316e operates as the outlet of third bidirectional pump 310c, and sixth port 316f operates as the inlet of third bidirectional pump 310c. Therefore, the second bidirectional pump 310b draws hydraulic fluid from the first hydraulic line section 334a through the third port 316c and discharges the hydraulic fluid into the second hydraulic line section 334b ​​through the fourth port 316d; the third bidirectional pump 310c draws hydraulic fluid from the fourth hydraulic line section 334d through the sixth port 316f and discharges the hydraulic fluid into the third hydraulic line section 334c through the fifth port 316e. Thus, the second and third bidirectional pumps 310b and 310c can operate to increase the fluid pressure in the second and third hydraulic lines 332b and 332c, thereby increasing the pressure in the second compression chamber 326b of the right front shock absorber 302b and the third compression chamber 326c of the left rear shock absorber 302c, making the right front shock absorber 302b and the left rear shock absorber 302c more difficult to compress.

[0098] Figure 17The diagram illustrates a suspension system 300 in a fully adaptive active operating mode, enabling dynamic active control of roll, pitch, torsion, and roll moment distribution. The controller 380 initiates the fully adaptive active operating mode by closing the left front shut-off valve 344a, right front shut-off valve 344b, left rear shut-off valve 344c, right rear shut-off valve 344d, and reservoir shut-off valve 346. The controller 380 can then activate the second and third bidirectional pumps 310b and 310c to pump hydraulic fluid in the same direction—either pumping hydraulic fluid to the front axle along the third and fifth directions 315c and 315e, or pumping hydraulic fluid to the rear axle along the fourth and sixth directions 315d and 315f—thereby altering the pitch stiffness of the suspension system 300 and / or adjusting the roll moment distribution of the front shock absorbers 302a and 302b relative to the rear shock absorbers 302c and 302d. Alternatively, controller 380 may subsequently activate the second and third bidirectional pumps 310b and 310c to pump hydraulic fluid in opposite directions (e.g., along the third and sixth directions 315c and 315f or the fourth and fifth directions 315d and 315e). Simultaneously or at different times, controller 380 may open / close the first and second distribution line shut-off valves 345a and 345b and activate the first bidirectional pump 310a to pump hydraulic fluid through the fluid distribution line 331 along the first or second direction 315a and 315b to achieve the active roll control described above. This active roll control can work in conjunction with the active pitch control and roll moment distribution control achieved through the operation of the second and third bidirectional pumps 310b and 310c, or it can operate independently.

[0099] Figure 18The suspension system 300 is shown when the controller 380 activates the pressure control operation mode. To increase the fluid pressure in the hydraulic circuits 320a, 320b, 320c, and 320d, the controller 380 activates the first bidirectional pump 310a, which pumps hydraulic fluid from the hydraulic fluid reservoir 312 along the first direction 315a through the reservoir pipeline 314, and then pumps it into the second longitudinal hydraulic pipeline 330b through the second distribution pipeline section 333b. In this example, the left front shut-off valve 344a, right front shut-off valve 344b, left rear shut-off valve 344c, and right rear shut-off valve 344d are all open, the first distribution pipeline shut-off valve 345a is closed, and the second distribution pipeline shut-off valve 345b and the reservoir shut-off valve 346 are both open. The first port 316a operates as the inlet of the first bidirectional pump 310a, and the second port 316b operates as the outlet of the first bidirectional pump 310a. Therefore, the first bidirectional pump 310a draws in hydraulic fluid from the first distribution pipeline section 333a through the first port 316a and discharges the hydraulic fluid into the second distribution pipeline section 333b through the second port 316b. Since the left front shut-off valve 344a, right front shut-off valve 344b, left rear shut-off valve 344c, and right rear shut-off valve 344d are all in the open state, the static pressure of all hydraulic circuits 320a, 320b, 320c, and 320d increases accordingly.

[0100] To reduce the fluid pressure in hydraulic circuits 320a, 320b, 320c, and 320d, controller 380 activates the first bidirectional pump 310a, which pumps hydraulic fluid along the second direction 315 from the second longitudinal hydraulic line 330b through the second distribution line section 333b, and pumps it into the hydraulic fluid storage tank 312 through the storage tank line 314. At this time, the left front shut-off valve 344a, right front shut-off valve 344b, left rear shut-off valve 344c, and right rear shut-off valve 344d are all open, the first distribution line shut-off valve 345a is closed, and the second distribution line shut-off valve 345b and the storage tank shut-off valve 346 are both open. The second port 316b operates as the inlet of the first bidirectional pump 310a, and the first port 316a operates as the outlet of the first bidirectional pump 310a. Therefore, the first bidirectional pump 310a draws in hydraulic fluid from the second distribution line section 333b through the second port 316b and discharges the hydraulic fluid into the first distribution line section 333a through the first port 316a. Since the left front shut-off valve 344a, right front shut-off valve 344b, left rear shut-off valve 344c, and right rear shut-off valve 344d are all open, the static pressure of all hydraulic circuits 320a, 320b, 320c, and 320d decreases accordingly.

[0101] Based on the above teachings, this disclosure can be modified and varied in many other ways, which may be implemented in ways other than those described above, but all of which are within the scope of the appended claims.

Claims

1. A suspension system, comprising: The left front shock absorber includes a first compression chamber and a first rebound chamber; The right front shock absorber includes a second compression chamber and a second rebound chamber; The left rear shock absorber includes a third compression chamber and a third rebound chamber; The right rear shock absorber includes a fourth compression chamber and a fourth rebound chamber; A first hydraulic circuit fluidly connects the first compression chamber of the left front shock absorber to the second rebound chamber of the right front shock absorber; A second hydraulic circuit fluidly connects the first rebound chamber of the left front shock absorber to the second compression chamber of the right front shock absorber. A third hydraulic circuit fluidly connects the third compression chamber of the left rear shock absorber to the fourth rebound chamber of the right rear shock absorber. A fourth hydraulic circuit fluidly connects the third rebound chamber of the left rear shock absorber to the fourth compression chamber of the right rear shock absorber. A first longitudinal hydraulic line extends between the first hydraulic circuit and the third hydraulic circuit, and fluidly connects the first hydraulic circuit and the third hydraulic circuit; A second longitudinal hydraulic line extends between the second hydraulic circuit and the fourth hydraulic circuit, and fluidly connects the second hydraulic circuit and the fourth hydraulic circuit. A fluid distribution line extends between the first longitudinal hydraulic line and the second longitudinal hydraulic line, and fluidly connects the first longitudinal hydraulic line and the second longitudinal hydraulic line; A first bidirectional pump is arranged along and fluidly connected to the fluid distribution pipe. The first bidirectional pump has a first operating mode and a second operating mode. The first operating mode is used to pump hydraulic fluid along a first direction through the fluid distribution pipe to a second longitudinal hydraulic line. The second operating mode is used to pump hydraulic fluid along a second direction through the fluid distribution pipe to the first longitudinal hydraulic line, such that the suspension system is configured to provide active roll stiffness when the first bidirectional pump is activated and passive roll stiffness when the first bidirectional pump is deactivated. A second bidirectional pump is arranged along and fluidly connected to the first longitudinal hydraulic line. The second bidirectional pump has a third operating mode and a fourth operating mode. The third operating mode is used to pump hydraulic fluid from the third hydraulic circuit to the first hydraulic circuit in a third direction. This fourth operating mode is used to pump hydraulic fluid from the first hydraulic circuit to the third hydraulic circuit in a fourth direction; as well as A third bidirectional pump is arranged along and fluidly connected to the second longitudinal hydraulic line. The third bidirectional pump has a fifth operating mode and a sixth operating mode. The fifth operating mode is used to pump hydraulic fluid from the fourth hydraulic circuit to the second hydraulic circuit in a fifth direction. The sixth operating mode is used to pump hydraulic fluid from the second hydraulic circuit to the fourth hydraulic circuit in a sixth direction.

2. The suspension system as claimed in claim 1, wherein, The first bidirectional pump includes a first port, which is configured as an inlet in the first operating mode and as an outlet in the second operating mode; and wherein the first bidirectional pump includes a second port, which is configured as an outlet in the first operating mode and as an inlet in the second operating mode.

3. The suspension system as described in claim 2, wherein, The fluid distribution pipeline includes: a first distribution pipeline section and a second distribution pipeline section; the first distribution pipeline section extends between the first port of the first bidirectional pump and the first longitudinal hydraulic pipeline and achieves fluid connection between the two; the second distribution pipeline section extends between the second port of the first bidirectional pump and the second longitudinal hydraulic pipeline and achieves fluid connection between the two.

4. The suspension system of claim 3, further comprising: The first distribution pipeline shut-off valve installed in the first distribution pipeline section is a dual-position electromechanical valve with a fully open position and a fully closed position. as well as The second distribution pipeline shut-off valve, which is installed in the second distribution pipeline section, is a two-position electromechanical valve with a fully open position and a fully closed position.

5. The suspension system of claim 4, further comprising: Storage tank; as well as A liquid storage tank pipeline extends between the liquid storage tank and at least one of the first distribution pipeline section and the second distribution pipeline section, thereby enabling fluid communication between the two.

6. The suspension system of claim 5, further comprising: The liquid storage tank shut-off valve installed in the liquid storage tank pipeline is a dual-position electromechanical valve with a fully open position and a fully closed position.

7. The suspension system of claim 1, further comprising: The left front axle pipe extends between the first hydraulic line and the second hydraulic line at a location adjacent to the left front shock absorber, and enables fluid communication between the two lines. The right front axle pipe extends between the first hydraulic line and the second hydraulic line at a location adjacent to the right front shock absorber, and enables fluid communication between the two lines. A left rear axle connecting line, located adjacent to the left rear shock absorber, extends between the third and fourth hydraulic lines, enabling fluid communication between these two lines; and The right rear axle pipeline extends between the third hydraulic pipeline and the fourth hydraulic pipeline at a location adjacent to the right rear shock absorber, thereby enabling fluid communication between the two pipelines.

8. The suspension system of claim 7, further comprising: The left front shut-off valve located in the left front axle pipeline; The right front shut-off valve is located in the right front axle pipeline; The left rear shut-off valve located in the left rear axle pipeline; as well as The right rear shut-off valve is located in the right rear axle pipeline. The left front shut-off valve, the right front shut-off valve, the left rear shut-off valve, and the right rear shut-off valve are all dual-position electromechanical valves, each with a fully open position and a fully closed position.

9. The suspension system as claimed in claim 8, wherein, The first hydraulic circuit includes a first hydraulic line and a first pair of variable control valves disposed at opposite ends of the first hydraulic line. The first hydraulic line extends between the first compression chamber of the left front shock absorber and the second rebound chamber of the right front shock absorber and achieves fluid connection between the two. The second hydraulic circuit includes a second hydraulic line and a second pair of variable control valves located at opposite ends of the second hydraulic line. The second hydraulic line extends between the first rebound chamber of the left front shock absorber and the second compression chamber of the right front shock absorber and achieves fluid connection between the two. The third hydraulic circuit includes a third hydraulic line and a third pair of variable control valves located at opposite ends of the third hydraulic line. The third hydraulic line extends between the third compression chamber of the left rear shock absorber and the fourth rebound chamber of the right rear shock absorber, achieving fluid connection between the two. The fourth hydraulic circuit includes a fourth hydraulic line and a fourth pair of variable control valves located at opposite ends of the fourth hydraulic line. The fourth hydraulic line extends between the third rebound chamber of the left rear shock absorber and the fourth compression chamber of the right rear shock absorber and enables fluid connection between the two.

10. A suspension system, comprising: The left front shock absorber includes a first compression chamber and a first rebound chamber; The right front shock absorber includes a second compression chamber and a second rebound chamber; The left rear shock absorber includes a third compression chamber and a third rebound chamber; The right rear shock absorber includes a fourth compression chamber and a fourth rebound chamber; A first hydraulic circuit fluidly connects the first compression chamber of the left front shock absorber to the second rebound chamber of the right front shock absorber; A second hydraulic circuit fluidly connects the first rebound chamber of the left front shock absorber to the second compression chamber of the right front shock absorber. A third hydraulic circuit fluidly connects the third compression chamber of the left rear shock absorber to the fourth rebound chamber of the right rear shock absorber. A fourth hydraulic circuit fluidly connects the third rebound chamber of the left rear shock absorber to the fourth compression chamber of the right rear shock absorber. A first longitudinal hydraulic line extends between the first hydraulic circuit and the third hydraulic circuit, and fluidly connects the first hydraulic circuit and the third hydraulic circuit; A second longitudinal hydraulic line extends between the second hydraulic circuit and the fourth hydraulic circuit, and fluidly connects the second hydraulic circuit and the fourth hydraulic circuit. A fluid distribution line extends between the first longitudinal hydraulic line and the second longitudinal hydraulic line, and fluidly connects the first longitudinal hydraulic line and the second longitudinal hydraulic line; as well as A first bidirectional pump, arranged and fluidly connected to the fluid distribution pipe, has a first operating mode and a second operating mode. The first operating mode pumps hydraulic fluid along a first direction through the fluid distribution pipe to a second longitudinal hydraulic line; the second operating mode pumps hydraulic fluid along a second direction through the fluid distribution pipe to the first longitudinal hydraulic line, such that the suspension system is configured to provide active roll stiffness when the first bidirectional pump is activated and passive roll stiffness when the first bidirectional pump is deactivated. A controller electrically connected to the first bidirectional pump and programmed to activate either the first operating mode or the second operating mode of the first bidirectional pump. A first distribution line shut-off valve is disposed in the fluid distribution line between the first bidirectional pump and the first longitudinal hydraulic line; A second distribution line shut-off valve is disposed in the fluid distribution line between the first bidirectional pump and the second longitudinal hydraulic line; The left front axle pipeline extends between the first hydraulic pipeline and the second hydraulic pipeline, enabling fluid communication between the two pipelines. Left front shut-off valve, which is located in the left front axle pipeline; The right front axle pipeline extends between the first hydraulic pipeline and the second hydraulic pipeline, and enables fluid communication between the two pipelines. The right front shut-off valve is located in the right front axle pipeline; The left rear axle pipeline extends between the third and fourth hydraulic lines, enabling fluid communication between these two lines. Left rear shut-off valve, which is located in the left rear axle pipeline; A right rear axle pipeline extends between the third and fourth hydraulic lines, enabling fluid communication between these two lines; and The right rear shut-off valve is located in the right rear axle pipeline. Among them, the first distribution pipeline shut-off valve, the second distribution pipeline shut-off valve, the left front shut-off valve, the right front shut-off valve, the left rear shut-off valve and the right rear shut-off valve are all dual-position electromechanical valves, each having a fully open position and a fully closed position. A second bidirectional pump, arranged and fluidly connected to the first longitudinal hydraulic line, has a third operating mode and a fourth operating mode. The third operating mode pumps hydraulic fluid in a third direction from the third hydraulic circuit to the first hydraulic circuit; the fourth operating mode pumps hydraulic fluid in a fourth direction from the first hydraulic circuit to the third hydraulic circuit. A third bidirectional pump, which is arranged along and fluidly connected to the second longitudinal hydraulic line, has a fifth operating mode and a sixth operating mode. The fifth operating mode is used to pump hydraulic fluid from the fourth hydraulic circuit to the second hydraulic circuit in a fifth direction; the sixth operating mode is used to pump hydraulic fluid from the second hydraulic circuit to the fourth hydraulic circuit in a sixth direction.

11. The suspension system of claim 10, wherein, The controller is programmed to start: Passive tilt control operation mode: wherein the left front shut-off valve, the right front shut-off valve, the left rear shut-off valve and the right rear shut-off valve are all in the fully closed position, the first distribution pipeline shut-off valve and the second distribution pipeline shut-off valve are in the fully closed position, and the first bidirectional pump is in a stopped state.

12. The suspension system of claim 10, wherein, The controller is programmed to start: First active roll moment distribution control operation mode: In the third operation mode, the second bidirectional pump is activated, and in the fifth operation mode, the third bidirectional pump is activated to increase the fluid pressure in the first hydraulic circuit and the second hydraulic circuit, and to increase the passive roll stiffness of the left front shock absorber and the right front shock absorber. as well as Second active roll moment distribution control mode: In the fourth operating mode, the second bidirectional pump is activated, and in the sixth operating mode, the third bidirectional pump is activated to increase the fluid pressure in the third hydraulic circuit and the fourth hydraulic circuit, and to increase the passive roll stiffness of the left rear shock absorber and the right rear shock absorber.

13. The suspension system of claim 10, wherein, The controller is programmed to start: First pitch control operation mode: In the third operation mode, the second bidirectional pump is activated, and in the fifth operation mode, the third bidirectional pump is activated to increase the fluid pressure in the first hydraulic circuit and the second hydraulic circuit, and to increase the compressive stiffness of the left front shock absorber and the right front shock absorber. as well as Second pitch control operation mode: In the fourth operation mode, the second bidirectional pump is activated, and in the sixth operation mode, the third bidirectional pump is activated to increase the fluid pressure in the third hydraulic circuit and the fourth hydraulic circuit, and to increase the compressive stiffness of the left rear shock absorber and the right rear shock absorber.

14. The suspension system of claim 10, wherein, The controller is programmed to start: Torsional control operation mode: wherein the second bidirectional pump is started in the third operation mode and the third bidirectional pump is started in the sixth operation mode; or the second bidirectional pump is started in the fourth operation mode and the third bidirectional pump is started in the fifth operation mode.

15. The suspension system of claim 10, wherein, The controller is programmed to start: First Comfort Operation Mode: The left front shut-off valve, the right front shut-off valve, the left rear shut-off valve, and the right rear shut-off valve are all in the fully open position, the first distribution pipeline shut-off valve and the second distribution pipeline shut-off valve are in the fully closed position, and the first bidirectional pump is in a stopped state. as well as Second Comfort Operation Mode: The left front shut-off valve, the right front shut-off valve, the left rear shut-off valve, and the right rear shut-off valve are all in the fully open position, the first distribution pipeline shut-off valve and the second distribution pipeline shut-off valve are in the fully open position, and the first bidirectional pump is in a stopped state and in an idling state.

16. A suspension system, comprising: The left front shock absorber includes a first compression chamber and a first rebound chamber; The right front shock absorber includes a second compression chamber and a second rebound chamber; The left rear shock absorber includes a third compression chamber and a third rebound chamber; The right rear shock absorber includes a fourth compression chamber and a fourth rebound chamber; A first hydraulic circuit fluidly connects the first compression chamber of the left front shock absorber to the second rebound chamber of the right front shock absorber; A second hydraulic circuit fluidly connects the first rebound chamber of the left front shock absorber to the second compression chamber of the right front shock absorber. A third hydraulic circuit fluidly connects the third compression chamber of the left rear shock absorber to the fourth rebound chamber of the right rear shock absorber. A fourth hydraulic circuit fluidly connects the third rebound chamber of the left rear shock absorber to the fourth compression chamber of the right rear shock absorber. A first longitudinal hydraulic line extends between the first hydraulic circuit and the third hydraulic circuit, and fluidly connects the first hydraulic circuit and the third hydraulic circuit; A second longitudinal hydraulic line extends between the second hydraulic circuit and the fourth hydraulic circuit, and fluidly connects the second hydraulic circuit and the fourth hydraulic circuit. A fluid distribution line extends between the first longitudinal hydraulic line and the second longitudinal hydraulic line, and fluidly connects the first longitudinal hydraulic line and the second longitudinal hydraulic line; as well as A first bidirectional pump is arranged along and fluidly connected to the fluid distribution pipe. The first bidirectional pump has a first operating mode and a second operating mode. The first operating mode is used to pump hydraulic fluid along a first direction through the fluid distribution pipe to a second longitudinal hydraulic line. The second operating mode is used to pump hydraulic fluid along a second direction through the fluid distribution pipe to the first longitudinal hydraulic line, such that the suspension system is configured to provide active roll stiffness when the first bidirectional pump is activated and passive roll stiffness when the first bidirectional pump is deactivated. A controller electrically connected to the first bidirectional pump and programmed to start the first bidirectional pump in either the first operating mode or the second operating mode. A first distribution line shut-off valve is disposed in the fluid distribution line between the first bidirectional pump and the first longitudinal hydraulic line; A second distribution line shut-off valve is disposed in the fluid distribution line between the first bidirectional pump and the second longitudinal hydraulic line; The left front axle pipeline extends between the first hydraulic pipeline and the second hydraulic pipeline, enabling fluid communication between the two pipelines. Left front shut-off valve, which is located in the left front axle pipeline; The right front axle pipeline extends between the first hydraulic pipeline and the second hydraulic pipeline, and enables fluid communication between the two pipelines. The right front shut-off valve is located in the right front axle pipeline; The left rear axle pipeline extends between the third and fourth hydraulic lines, enabling fluid communication between these two lines. Left rear shut-off valve, which is located in the left rear axle pipeline; A right rear axle pipeline extends between the third and fourth hydraulic lines, enabling fluid communication between these two lines; and The right rear shut-off valve is located in the right rear axle pipeline. Among them, the first distribution pipeline shut-off valve, the second distribution pipeline shut-off valve, the left front shut-off valve, the right front shut-off valve, the left rear shut-off valve, and the right rear shut-off valve are all dual-position electromechanical valves, each having a fully open position and a fully closed position. The controller is programmed to start: Passive tilt control operation mode: wherein the left front shut-off valve, the right front shut-off valve, the left rear shut-off valve and the right rear shut-off valve are all in the fully closed position, the first distribution pipeline shut-off valve and the second distribution pipeline shut-off valve are in the fully closed position, and the first bidirectional pump is in the off state. The controller is programmed to start: First active roll control operating mode: wherein the left front shut-off valve, the right front shut-off valve, the left rear shut-off valve, and the right rear shut-off valve are all in the fully closed position, the first distribution line shut-off valve and the second distribution line shut-off valve are in the fully open position, and in the first operating mode, the first bidirectional pump is activated to pump hydraulic fluid along the first direction from the first longitudinal hydraulic line to the second longitudinal hydraulic line through the fluid distribution line, thereby increasing the fluid pressure in the second hydraulic circuit and the fourth hydraulic circuit, and increasing the compressive stiffness of the right front shock absorber and the right rear shock absorber; and Second active roll control operating mode: wherein the left front shut-off valve, the right front shut-off valve, the left rear shut-off valve, and the right rear shut-off valve are all in the fully closed position, the first distribution line shut-off valve and the second distribution line shut-off valve are in the fully open position, and in the second operating mode, the first bidirectional pump is started to pump hydraulic fluid from the second longitudinal hydraulic line to the first longitudinal hydraulic line through the fluid distribution line along the second direction, thereby increasing the fluid pressure in the first hydraulic circuit and the third hydraulic circuit, and increasing the compressive stiffness of the left front shock absorber and the left rear shock absorber.

17. A suspension system, comprising: The left front shock absorber includes a first compression chamber and a first rebound chamber; The right front shock absorber includes a second compression chamber and a second rebound chamber; The left rear shock absorber includes a third compression chamber and a third rebound chamber; The right rear shock absorber includes a fourth compression chamber and a fourth rebound chamber; A first hydraulic circuit fluidly connects the first compression chamber of the left front shock absorber to the second rebound chamber of the right front shock absorber; A second hydraulic circuit fluidly connects the first rebound chamber of the left front shock absorber to the second compression chamber of the right front shock absorber. A third hydraulic circuit fluidly connects the third compression chamber of the left rear shock absorber to the fourth rebound chamber of the right rear shock absorber. A fourth hydraulic circuit fluidly connects the third rebound chamber of the left rear shock absorber to the fourth compression chamber of the right rear shock absorber. A first longitudinal hydraulic line extends between the first hydraulic circuit and the third hydraulic circuit, and fluidly connects the first hydraulic circuit and the third hydraulic circuit; A second longitudinal hydraulic line extends between the second hydraulic circuit and the fourth hydraulic circuit, and fluidly connects the second hydraulic circuit and the fourth hydraulic circuit. A liquid storage tank, wherein the liquid storage tank is configured to be in fluid communication with at least one of the first longitudinal hydraulic line and the second longitudinal hydraulic line; A fluid distribution line extends between the first longitudinal hydraulic line and the second longitudinal hydraulic line, and fluidly connects the first longitudinal hydraulic line and the second longitudinal hydraulic line; A first bidirectional pump is arranged along and fluidly connected to the fluid distribution pipe. The first bidirectional pump has a first operating mode and a second operating mode. The first operating mode is used to pump hydraulic fluid along a first direction through the fluid distribution pipe to a second longitudinal hydraulic line. The second operating mode is used to pump hydraulic fluid along a second direction through the fluid distribution pipe to the first longitudinal hydraulic line, such that the suspension system is configured to provide active roll stiffness when the first bidirectional pump is activated and passive roll stiffness when the first bidirectional pump is deactivated. A second bidirectional pump is arranged along and fluidly connected to the first longitudinal hydraulic line. The second bidirectional pump has a third operating mode and a fourth operating mode. The third operating mode is used to pump hydraulic fluid from the third hydraulic circuit to the first hydraulic circuit in a third direction. This fourth operating mode is used to pump hydraulic fluid from the first hydraulic circuit to the third hydraulic circuit in a fourth direction; as well as A third bidirectional pump is arranged along and fluidly connected to the second longitudinal hydraulic line. The third bidirectional pump has a fifth operating mode and a sixth operating mode. The fifth operating mode is used to pump hydraulic fluid from the fourth hydraulic circuit to the second hydraulic circuit in a fifth direction. The sixth operating mode is used to pump hydraulic fluid from the second hydraulic circuit to the fourth hydraulic circuit in a sixth direction.

Images