A control method for a powertrain cylinder deactivation suspension system

Abstract

The application provides a control method of a suspension system for cylinder deactivation of a power assembly, and the method comprises the following steps: an electronic control unit judges the operating condition of a cylinder to obtain cylinder deactivation information; the main excitation order of the power assembly torque is determined according to the different deactivation information; the isolation strategy is determined to avoid the excitation frequency, reduce the resonance phenomenon, and the control method of reducing the resonance phenomenon, so that the electronic control unit judges the deactivation condition of the power assembly, and the suspension unit is punched in through the judgment result of the electronic control unit, so that the stiffness of the suspension unit adaptively changes according to the different number of deactivation, to improve the isolation effect, and the suspension unit and the power assembly can avoid the excitation frequency of the torque order and reduce the occurrence of the resonance phenomenon.

Description

Technical Field

[0001] This application relates to the field of engine equipment and control technology, specifically to a control method for a powertrain cylinder deactivation suspension system. Background Technology

[0002] Multi-cylinder engines, especially six-cylinder engines, typically use rubber mounts for vibration isolation during operation. Their stiffness variation range is relatively small, usually only ensuring the powertrain mount system avoids vibrations at the third-order torque excitation frequency—the excitation frequency when all six cylinders are operating simultaneously. If two or three cylinders of a six-cylinder engine are deactivated, for example, when a truck is unloaded or fully loaded, the effective displacement of the powertrain can be flexibly and effectively reduced by varying the number of cylinders engaged, thus reducing fuel consumption. In this case, the main torque excitation order of the powertrain changes. While this can effectively utilize fuel resources, the change in the main excitation order inevitably leads to overlap between the vibration isolation system and the powertrain frequency at certain speeds, causing resonance. This results in increased vibration and noise in the diesel engine, especially at low speeds where the vibration frequency is low and the amplitude is large, making the resonance effect more significant and reducing driver comfort.

[0003] Therefore, existing technologies need further improvement and enhancement. Summary of the Invention

[0004] This application provides a control method for a powertrain cylinder deactivation suspension system to solve the problem that existing suspension systems are difficult to adapt to different cylinder deactivation conditions and exhibit significant resonance phenomena.

[0005] The technical solution adopted in this application is as follows:

[0006] This application provides a cylinder deactivation suspension system for a powertrain. The suspension system includes suspension units matched to the number of cylinders, an electronic control unit, and an air supply unit connected to multiple suspension units respectively. The air supply unit presses into the suspension units and changes the stiffness of the suspension units according to the amount of press.

[0007] In a preferred embodiment of this application, the suspension unit includes a switching valve connected to the air supply unit and an air bladder connected to the switching valve. The air bladder is provided with an elastic element and a damping element. The overall stiffness of the suspension unit is the sum of the stiffness of the air bladder and the stiffness of the elastic element.

[0008] In a preferred embodiment of this application, the switching valve controls the amount of pressure supplied by the air supply unit into the airbag. The airbag has low-pressure, medium-pressure and high-pressure states depending on the amount of pressure, so that the stiffness of the suspension unit is Ka, Ka+Kb and Ka+Kc respectively.

[0009] In a preferred embodiment of this application, the number of cylinders is six, and the number of suspension units is also six.

[0010] This application also provides a control method for a suspension system, the method comprising the following steps:

[0011] The electronic control unit judges the operating conditions of the cylinder and obtains the cylinder shutdown information;

[0012] The main excitation order of the powertrain torque is determined based on the different cylinder deactivation information.

[0013] By determining the different orders of the main excitation, vibration isolation strategies can be implemented to avoid the excitation frequency and reduce resonance phenomena.

[0014] As a preferred embodiment of this application, if the electronic control unit determines that all cylinders are working normally, it determines that the main excitation order is 3, and adopts vibration isolation strategy 1 in which all suspension units are in a medium-pressure state or vibration isolation strategy 2 in which all suspension units are in a high-pressure state.

[0015] As a preferred embodiment of this application, if the electronic control unit determines that three of the cylinders have stopped, it determines that the main excitation order is 1.5 and adopts a vibration isolation strategy 3 in which four suspension units are in a high-pressure state and the remaining two suspension units are in a low-pressure state.

[0016] As a preferred embodiment of this application, if the electronic control unit determines that two of the cylinders have stopped, and determines that the main excitation order is 1, it adopts strategy 4 in which all the suspension units are in a low-pressure state or strategy 5 in which four suspension units are in a medium-pressure state and two suspension units are in a low-pressure state.

[0017] In a preferred embodiment of this application, in strategy 3, the first suspension unit, the third suspension unit, the fourth suspension unit, and the sixth suspension unit are in a high-pressure state, while the second suspension unit and the fifth suspension unit are in a low-pressure state; or, the first suspension unit, the second suspension unit, the fourth suspension unit, and the fifth suspension unit are in a high-pressure state, while the suspension units at the third suspension unit and the sixth suspension unit are in a low-pressure state.

[0018] In a preferred embodiment of this application, in strategy 5, the first suspension unit, the third suspension unit, the fourth suspension unit, and the sixth suspension unit are in a medium-pressure state, and the second suspension unit and the fifth suspension unit are in a low-pressure state; or, the first suspension unit, the second suspension unit, the fourth suspension unit, and the fifth suspension unit are in a medium-pressure state, and the third suspension unit and the sixth suspension unit are in a low-pressure state.

[0019] Due to the adoption of the above technical solution, the technical effects achieved by this application are as follows:

[0020] 1. This application uses an electronic control unit to determine the cylinder deactivation status of the powertrain and uses the determination result of the electronic control unit to press into the suspension unit, so that the stiffness of the suspension unit adapts to the different number of cylinder deactivations, thereby improving the vibration isolation effect. This allows the suspension unit and the powertrain to avoid excitation speeds and frequencies of different torque orders, reducing the occurrence of resonance, reducing vibration and noise, and improving the driver's driving comfort.

[0021] 2. This application, by setting the suspension unit to include an airbag, an elastic element, and a damping element, ensures that the overall stiffness of the suspension unit is composed of the variable stiffness of the airbag and the fixed stiffness of the elastic element. This guarantees that the stiffness of the suspension unit is variable, and the stiffness of the airbag can be changed by different pressures from the air supply unit. This makes operation convenient and the structure simple. Furthermore, the damping element can provide damping force to cope with changes in the stiffness of the airbag and the elastic element under different stiffness conditions, resulting in smoother vibration.

[0022] 3. This application sets different vibration isolation strategies by varying the excitation order for different numbers of cylinders deactivated, thereby obtaining different vibration isolation system stiffnesses under different cylinder deactivation conditions. The varying stiffness reduces vibration and noise generated under different excitation orders, and ensures that the rotational speed and frequency of the vibration isolation unit avoid the rotational speed and frequency under different torque orders, thus reducing resonance and ensuring smooth powertrain operation and reducing noise generated during powertrain operation. Furthermore, by arranging the mounting units of the six-cylinder engine in pairs, vibration can be better distributed, further improving the vibration isolation effect and enhancing powertrain reliability. Attached Figure Description

[0023] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and, together with their description, serve to explain this application and do not constitute an undue limitation of the invention. In the drawings:

[0024] Figure 1 An overall structural diagram of the powertrain mounting system in one embodiment provided in this application;

[0025] Figure 2 This application provides a schematic diagram of the suspension system in one embodiment.

[0026] Figure 3 Excitation frequency description for one embodiment provided in this application;

[0027] Figure 4 A nonlinear damping curve provided in one embodiment of this application;

[0028] Figure 5A line graph showing the relationship between the third-order principal excitation frequency and the natural frequency in one embodiment provided in this application;

[0029] Figure 6 A line graph showing the relationship between the 1.5th order master excitation frequency and the natural frequency in one embodiment provided in this application;

[0030] Figure 7 A line graph showing the relationship between the first-order master excitation frequency and the natural frequency in one embodiment provided in this application.

[0031] Figure label:

[0032] 1-First suspension unit; 2-Second suspension unit; 3-Third suspension unit; 4-Fourth suspension unit; 5-Fifth suspension unit; 6-Sixth suspension unit; 7-Engine; 8-Transmission; 9-Air supply unit; 10-Electronic control unit; 11-Switching valve; 12-Elastic element; 13-Airbag; 14-Damping element. Detailed Implementation

[0033] To more clearly illustrate the overall concept of this application, a detailed explanation is provided below with reference to the accompanying drawings.

[0034] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, this application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of this application is not limited to the specific embodiments disclosed below.

[0035] Furthermore, it should be understood in the description of this application that the terms "bottom," "inner," "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0036] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0037] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0038] like Figures 1 to 2 As shown, this application provides a cylinder deactivation suspension system for a powertrain. The suspension system includes a suspension unit matching the number of cylinders, an electronic control unit 10, and an air supply unit 9 connected to multiple suspension units respectively. The air supply unit 9 presses into the suspension unit and changes the stiffness of the suspension unit according to the amount of pressing.

[0039] In a preferred embodiment of this application, the suspension unit includes a switching valve 11 connected to the air supply unit 9, and an airbag 13 connected to the switching valve 11. The airbag 13 has an elastic element 12 and a damping element 14 disposed inside. The overall stiffness of the suspension unit is the sum of the stiffness of the airbag 13 and the stiffness of the elastic element 12. Figure 4 This represents the relative displacement value due to damping.

[0040] In this application, a six-cylinder engine is used as an example, wherein the number of suspension units is set to six, each located at a different cylinder position. The powertrain includes an engine 7 and a transmission 8, and also includes a first suspension unit 1, a second suspension unit 2, a third suspension unit 3, a fourth suspension unit 4, a fifth suspension unit 5, and a sixth suspension unit 6, as shown below. Figure 1 As shown, the suspension unit is located at the bottom of the powertrain, which can greatly reduce the vibration transmitted from the engine to the frame and body.

[0041] Furthermore, the switching valve 11 controls the amount of pressure supplied by the air supply unit 9 into the airbag 13. The airbag 13 has low pressure, medium pressure and high pressure states depending on the amount of pressure, so that the stiffness of the suspension unit is Ka, Ka+Kb and Ka+Kc respectively.

[0042] It is understood that the control of the stamping amount by the switching valve 11 can be controlled by the electronic control unit 10, and the electronic control unit 10 has a receiving component, a processing component and a transmitting component. The switching valve 11 is an electrically controlled valve and is set in the control component connected to the transmitting component, so as to realize the transmission and control of information.

[0043] In addition, Kb and Kc are the stiffness of the airbag 13 when it is in medium pressure and high pressure, respectively. Since the air pressure is small in the low pressure state, this application does not consider the stiffness of the airbag 13 in the low pressure state. That is, the total stiffness of the suspension unit in the low pressure state is the stiffness Ka of the elastic element 12. In other words, the relationship between the stiffness of the suspension unit in different states is Ka < Ka + Kb < Ka + Kc.

[0044] This application uses an electronic control unit 10 to determine the cylinder deactivation status of the powertrain. Based on the determination result, pressure is applied to the suspension unit, causing the stiffness of the suspension unit to adapt to different cylinder deactivation levels. This improves vibration isolation, allowing the isolation unit and powertrain to avoid excitation speeds and frequencies of different torque orders, reducing resonance, vibration, and noise, and improving driver comfort. Furthermore, the airbag 13 in the suspension unit provides air supply and de-inflation to achieve low, medium, and high pressure states, thus obtaining different stiffness levels. This ensures the reliability of the powertrain and vehicle frame structure, preventing resonance between the powertrain and suspension system when cylinder deactivation occurs.

[0045] This application also provides a control method for a suspension system, applicable to the aforementioned suspension system, and the specific control method includes the following steps:

[0046] The electronic control unit judges the operating conditions of the cylinder and obtains the cylinder shutdown information;

[0047] The main excitation order of the powertrain torque is determined based on the different cylinder deactivation information.

[0048] By determining the different excitation orders, vibration isolation strategies can be implemented to avoid the excitation frequency and reduce resonance phenomena.

[0049] The electronic control unit acquires cylinder deactivation information and processes it through internal processing components to determine the excitation order of the powertrain. This information is then transmitted to the control components of the switching valve 11 via the transmitting component. Different vibration isolation strategies are preset for different excitation orders to control the mounting units at different positions in different cylinders to perform stamping and control the stamping amount to obtain different stiffnesses, thereby largely avoiding the occurrence of resonance.

[0050] Furthermore, if the electronic control unit determines that all cylinders are working normally, it determines that the main excitation order is 3, and adopts either vibration isolation strategy 1 where all suspension units are in a medium-pressure state or vibration isolation strategy 2 where all suspension units are in a high-pressure state.

[0051] If the electronic control unit determines that three of the cylinders have stopped, it determines that the main excitation order is 1.5 and adopts a vibration isolation strategy 3 in which four suspension units are in a high-pressure state and the remaining two suspension units are in a low-pressure state.

[0052] If the electronic control unit determines that two cylinders have stopped, and determines that the main excitation order is 1, it adopts strategy 4, in which all suspension units are in a low-pressure state, or strategy 5, in which four suspension units are in a medium-pressure state and two suspension units are in a low-pressure state.

[0053] It is understandable that this application takes a six-cylinder engine as an example. Since there are nearly a hundred ways to arrange and combine the six mounting units of a six-cylinder engine, in order to ensure the structural reliability of the powertrain and the vehicle frame, this application selects five of the most representative strategies for description, thereby largely avoiding the resonance phenomenon between the powertrain and the mounting system that occurs when the powertrain cylinders deactivate.

[0054] During use, after two or three cylinders of a six-cylinder engine are deactivated, the main torque excitation order of the powertrain changes from the 3rd harmonic main excitation to the 1st or 1.5th harmonic main excitation. When using conventional rubber mount units, the powertrain and the mount system will experience system resonance and a significant increase in powertrain vibration at certain speeds.

[0055] Specifically, such as Figure 3 As shown, Figure 3 As can be seen from the explanation of the main excitation frequency, the main excitation frequency of the powertrain gradually increases as the speed increases. Specifically, at a certain speed, the frequency is as follows: Figure 3 At the location highlighted by the dashed line, the 1.5th harmonic main excitation frequency line intersects with the natural frequency lines of the powertrain and suspension system. At this time, the powertrain will resonate due to the frequency overlap. Similarly, the 1st harmonic main excitation frequency line intersects with the natural frequency lines of the powertrain and suspension system, and will also resonate due to the frequency overlap.

[0056] In other words, the change in the harmonic main excitation frequency caused by cylinder deactivation is the main cause of resonance. This application addresses the different main excitation frequency changes caused by different cylinder deactivation states by setting five different strategies, specifically:

[0057] Strategy 1 uses cylinders 1 to 6, that is, the first suspension unit 1 to the second suspension unit 6 are all in a medium pressure state. At this time, the total stiffness of the suspension unit is 6 (Ka+Kb).

[0058] Strategy 2 uses cylinders 1 to 6, that is, the first suspension unit 1 to the second suspension unit 6 are all in a high-pressure state. At this time, the total stiffness of the suspension unit is 6 (Ka+Kc).

[0059] Strategy 3 involves the first, third, fourth, and sixth suspension units being under high pressure, while the second and fifth suspension units are under low pressure. In this case, the total stiffness of the suspension units is 4(Ka+Kc)+2Ka. Alternatively, the first, second, fourth, and fifth suspension units are under high pressure, while the third and sixth suspension units are under low pressure. In this case, the total stiffness of the suspension units is also 4(Ka+Kc)+2Ka.

[0060] Strategy 4 involves the first, third, fourth, and sixth suspension units being under medium pressure, while the second and fifth suspension units are under low pressure. In this case, the total stiffness of the suspension units is 4(Ka+Kb)+2Ka. Alternatively, the first, second, fourth, and fifth suspension units are under medium pressure, while the third and sixth suspension units are under low pressure. In this case, the total stiffness of the suspension units is also 4(Ka+Kb)+2Ka.

[0061] Strategy 5 involves all suspension units 1 to 6 being in a low-pressure state, at which point the total stiffness of the suspension units is 6Ka.

[0062] In other words, such as Figure 5 As shown, when all six cylinders are working normally, the main excitation order of the powertrain is the 3rd harmonic, and the vibration is relatively small. Therefore, strategy 1 or strategy 2 is selected to maximize the overall stiffness of the suspension system, improve the load-bearing capacity, avoid the main excitation frequency of the powertrain, and reduce the occurrence of resonance.

[0063] It is understandable that there are six cylinders, and each cylinder can be equipped with a suspension unit, that is, cylinders 1, 2, 3, 4, 5, and 6 are respectively the first suspension unit, the second suspension unit, the third suspension unit, the fourth suspension unit, the fifth suspension unit, and the sixth suspension unit.

[0064] like Figure 6 As shown, when three cylinders are working normally and the other three cylinders are stopped, the main excitation order of the powertrain is 1.5. Taking the stopping of cylinders 1, 2, and 3 or cylinders 4, 5, and 6 as an example, the vibration amplitude is moderate. Therefore, strategy 3 is selected to make the stiffness of the suspension system moderate. At this time, the damping block in the suspension system has a moderate effect, which can reduce vibration and avoid the 1.5 harmonic main excitation frequency of the powertrain, thus avoiding resonance.

[0065] like Figure 7As shown, when four cylinders are working normally and the other two cylinders are stopped, this application takes cylinders 1 and 6, cylinders 2 and 5, or cylinders 3 and 4 as examples. At this time, the vibration amplitude is too large. Therefore, strategy 4 or strategy 5 is selected to reduce the stiffness of the suspension system and increase the damping effect of the damping block. It also avoids the first harmonic main excitation frequency of the powertrain to prevent resonance.

[0066] It can be seen that, as Figures 5 to 7 As shown, in the speed range of 800 r / min to 2200 r / min, the main excitation frequency line does not intersect with the natural frequency line of the powertrain and the suspension system. Therefore, the powertrain and the suspension system will not resonate, thus avoiding frequency overlap and reducing resonance.

[0067] This application adapts to vibration and frequency changes under different cylinder deactivation conditions by adjusting the overall stiffness of the mounting unit and the powertrain. Furthermore, it sets different strategies to avoid frequencies at the excitation harmonics based on the changes in the excitation harmonics. The relationship between the excitation harmonics and stiffness is roughly that the higher the order of the excitation harmonics, the higher the stiffness of the mounting system required. Therefore, based on this principle, the settings and control methods in this application can be appropriately adjusted to adapt to cylinder deactivation control of other multi-cylinder engines.

[0068] It should be noted that this application optimizes the problem of small stiffness variation of traditional rubber suspension units and difficulty in adjusting for different cylinder stop conditions by setting up structures such as airbags and elastic elements in the suspension unit. In addition, the suspension unit structure has high reliability and reasonable arrangement, which is a pairwise relative distribution, which can reduce resonance to a greater extent.

[0069] For any parts not mentioned in this application, existing technologies may be used or referenced.

[0070] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0071] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A control method for a powertrain cylinder deactivation suspension system, characterized in that, The method includes the following steps: The electronic control unit judges the operating conditions of the cylinder and obtains the cylinder shutdown information; The main excitation order of the powertrain torque is determined based on the different cylinder deactivation information. By determining the different orders of the main excitation, the vibration isolation strategy can be used to avoid the excitation frequency and reduce resonance. If the electronic control unit determines that all cylinders are working normally, it determines that the main excitation order is 3, and adopts vibration isolation strategy 1 where all suspension units are in medium pressure or vibration isolation strategy 2 where all suspension units are in high pressure. If the electronic control unit determines that three of the cylinders have stopped, it determines that the main excitation order is 1.5 and adopts a vibration isolation strategy 3 in which four suspension units are in a high-pressure state and the remaining two suspension units are in a low-pressure state. If the electronic control unit determines that two cylinders have stopped, and determines that the main excitation order is 1, it adopts strategy 4, in which all suspension units are in a low-pressure state, or strategy 5, in which four suspension units are in a medium-pressure state and two suspension units are in a low-pressure state. The suspension system includes suspension units matching the number of cylinders, an electronic control unit, and an air supply unit connected to multiple suspension units respectively. The air supply unit presses into the suspension units and changes the stiffness of the suspension units according to the amount of press.

2. The control method for a powertrain cylinder deactivation suspension system as described in claim 1, characterized in that, The suspension unit includes a switching valve connected to the air supply unit and an air bladder connected to the switching valve. The air bladder is internally provided with an elastic element and a damping element. The overall stiffness of the suspension unit is the sum of the stiffness of the air bladder and the stiffness of the elastic element.

3. The control method for a powertrain cylinder deactivation suspension system as described in claim 2, characterized in that, The switching valve controls the amount of pressure supplied by the air supply unit into the airbag. The airbag has low-pressure, medium-pressure, and high-pressure states depending on the amount of pressure, so that the stiffness of the suspension unit is Ka, Ka+Kb, and Ka+Kc, respectively.

4. The control method for a powertrain cylinder deactivation suspension system as described in claim 3, characterized in that, The number of cylinders is six, and the number of suspension units is also six, including a first suspension unit, a second suspension unit, a third suspension unit, a fourth suspension unit, a fifth suspension unit, and a sixth suspension unit.

5. The control method for a powertrain cylinder deactivation suspension system as described in claim 1, characterized in that, In Strategy 3, the first, third, fourth, and sixth suspension units are in a high-pressure state, while the second and fifth suspension units are in a low-pressure state; or, The first, second, fourth, and fifth suspension units are in a high-pressure state, while the suspension units at the third and sixth suspension units are in a low-pressure state.

6. The control method for a powertrain cylinder deactivation suspension system as described in claim 1, characterized in that, In strategy 5, the first, third, fourth, and sixth suspension units are in a medium-pressure state, while the second and fifth suspension units are in a low-pressure state; or, The first, second, fourth, and fifth suspension units are in a medium-pressure state, while the third and sixth suspension units are in a low-pressure state.

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