Heavy-duty truck safe compartment lifting method based on suspension signals

Abstract

The invention provides a heavy-duty truck safe compartment lifting method based on a suspension signal, and relates to the technical field of new energy trucks, and the method comprises the following steps: when a cab lifting signal is received, an air bag is inflated and deflated according to a height valve reading, and a cab is lifted; whether the difference value of the left suspension difference value and the right suspension difference value is not smaller than a third preset threshold value or not is judged before the cab is disengaged from the rear suspension part; if yes, the air cylinder stops jacking; otherwise, the lock catch is unlocked; after the cab is separated from the rear suspension part, whether the difference value of the left suspension difference rate and the right suspension difference rate is not smaller than a fourth preset threshold value or not is judged; if yes, the air cylinder stops jacking; otherwise, the air cylinder continues to jack until the cab is lifted. In the lifting process of the cab compartment, the suspension heights of the front suspension air bag and the rear suspension air bag are analyzed, safety identification is conducted on the two stages before and after the cab compartment is separated from the rear suspension part, the safety of the compartment is further guaranteed when the compartment is lifted, the cab compartment is effectively prevented from overturning, and the safety is high.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy trucks, and in particular, to a method for safely lifting a heavy-load truck based on a suspension signal. Background Art

[0002] Freight trucks are generally called trucks, also known as trucks. They are mainly used to transport goods. Sometimes they also refer to cars that can tow other vehicles. They belong to the category of commercial vehicles. Generally, they can be divided into heavy and light types according to the weight of the vehicle. Most trucks use diesel engines as their power source, but some light trucks use gasoline, LPG or natural gas. With the large-scale development of new energy technology in the country, some trucks are also driven by new energy such as electricity.

[0003] As new energy trucks have better acceleration and deceleration performance, the shock and collision resistance requirements for new energy trucks are higher. The cab of new energy trucks generally adopts the structure of the suspension system for shock and collision resistance; the cab suspension system includes a front suspension assembly arranged between the front lower part of the cab and the frame and a rear suspension assembly arranged between the rear lower part of the cab and the frame; it mainly supports, flips and resists roll of the cab, and at the same time attenuates the vibration and impact transmitted to the cab by the uneven road surface during vehicle driving, guides the vertical movement of the cab relative to the ground, limits the roll and deflection movement of the cab, and improves ride comfort.

[0004] Current suspension assemblies all have multiple buffers on the front suspension assembly, and then multiple buffers on the rear suspension assembly. These buffers on the front and rear suspensions serve a simple distributed buffering function, and can only maintain the balance buffering of the cab compartment after the cab compartment is lowered. However, during the process of flipping up the cab compartment, the rear of the cab compartment is lifted up and separated from the rear suspension assembly, causing the rear suspension assembly to play almost no role. In particular, after the cab compartment rises from the rear suspension assembly, if the center of gravity of the compartment deviates, it may cause the compartment to shake or even overturn, causing loss of life and property.

[0005] Therefore, in order to solve the above problems, it is necessary for us to design a reasonable method for safe lifting of heavy-loaded trucks based on suspension signals. Summary of the invention

[0006] The purpose of the present invention is to provide a method for safely lifting the cabin of a heavy-loaded truck based on suspension signals. During the lifting process of the cab, the suspension heights of the front suspension airbags and the rear suspension airbags are analyzed by suspension signal, and the two stages before and after the cab is separated from the rear suspension part are safely identified, thereby further ensuring the safety of the cabin when it is lifted, effectively preventing the cab from overturning, and having high safety.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions:

[0008] A method for safely lifting a heavy-loaded truck based on a suspension signal, applicable to a safe lifting structure for a heavy-loaded truck based on a suspension signal, comprising a front suspension part and a rear suspension part; the front suspension part comprises a front suspension upper beam and a front suspension lower beam; the rear suspension part comprises a rear suspension upper beam and a rear suspension lower beam; the front suspension upper beam and the front suspension lower beam are connected via a front suspension left airbag and a front suspension right airbag; the rear suspension upper beam and the rear suspension lower beam are connected via a rear suspension left airbag and a rear suspension right airbag; the front suspension left airbag, the front suspension right airbag, the rear suspension left airbag and the rear suspension right airbag are all provided with a height valve for obtaining the airbag suspension height; the rear suspension upper beam is provided with a lock buckle for connecting with the bottom beam of the cab;

[0009] The method comprises the following steps:

[0010] S1: When receiving a cab lift signal, the height valve obtains the airbag suspension height in real time; when the suspension height is greater than a first predetermined threshold, the cushion airbag is deflated; and when the suspension height is less than the first predetermined threshold, the cushion airbag is inflated until the suspension height is stable, and the cab is lifted by the cylinder;

[0011] S2: determining whether the difference between the left suspension difference and the right suspension difference is not less than a third predetermined threshold before the suspension height of any one of the rear-suspended left airbag and the rear-suspended right airbag reaches the second predetermined threshold; if so, the cylinder stops lifting; otherwise, when the suspension height of any one of the rear-suspended left airbag and the rear-suspended right airbag reaches the second predetermined threshold, the lock is controlled to unlock, and step S3 is executed;

[0012] S3: Determine whether the difference between the left suspension differential rate and the right suspension differential rate is not less than a fourth predetermined threshold value; if so, the cylinder stops lifting; otherwise, no operation is performed, and the cylinder continues lifting until the cab is completely lifted.

[0013] As a preferred embodiment of the present invention, when executing step S2, the suspension height difference between the front-suspended left airbag and the rear-suspended left airbag is calculated and recorded as the left-side suspension difference;

[0014] Calculate the difference in suspension height between the front right airbag and the rear right airbag, and record it as the right side suspension difference.

[0015] As a preferred embodiment of the present invention, when executing step S2: specifically:

[0016] S21: acquiring a current left suspension difference and a current right suspension difference at a first predetermined time interval;

[0017] S22: Determine whether the difference between the left suspension difference and the right suspension difference is not less than a third predetermined threshold value, if so, stop executing the steps; otherwise, execute step S43;

[0018] S23: Determine whether the suspension height of any one of the rear-suspended left airbag and the rear-suspended right airbag reaches a second predetermined threshold, if so, control the lock to unlock; otherwise, return to step S41.

[0019] As a preferred embodiment of the present invention, when executing step S3, the left suspension difference is divided by the suspension height value of the rear-suspended left airbag to obtain the left suspension difference rate;

[0020] Divide the right side suspension difference by the suspension height of the rear right airbag to obtain the right side suspension difference rate.

[0021] As a preferred embodiment of the present invention, when executing step S3: specifically:

[0022] S31: acquiring the current left suspension difference rate and right suspension difference rate once every second predetermined time interval;

[0023] S32: Determine whether the difference between the left suspension differential rate and the right suspension differential rate is not less than a fourth predetermined threshold; if so, the cylinder stops lifting; otherwise, the cylinder continues lifting and executes step S33;

[0024] S33: Determine whether the cab is raised to a preset height; if so, the cab is raised and the cylinder stops lifting; otherwise, return to step S31.

[0025] As a preferred embodiment of the present invention, when executing step S1: establishing an electrical connection between the height valve and the lock buckle;

[0026] When executing step S2, the lock is unlocked by controlling the controller.

[0027] As a preferred embodiment of the present invention, the left end of the front suspension upper beam and the left end of the front suspension lower beam are connected by a front suspension left airbag; the right end of the front suspension upper beam and the right end of the front suspension lower beam are connected by a front suspension right airbag; the left end of the rear suspension upper beam and the left end of the rear suspension lower beam are connected by a rear suspension left airbag; the right end of the rear suspension upper beam and the right end of the rear suspension lower beam are connected by a rear suspension right airbag;

[0028] The front-suspended left airbag and the front-suspended right airbag are symmetrically arranged; the rear-suspended left airbag and the rear-suspended right airbag are symmetrically arranged.

[0029] As a preferred embodiment of the present invention, before executing step S1, the distance L1 between the front suspension left airbag and the front suspension right airbag and the center point of the front suspension upper beam is obtained; the distance L2 between the rear suspension left airbag and the rear suspension right airbag and the center point of the rear suspension upper beam is obtained;

[0030] The first predetermined threshold includes a front overhang predetermined threshold and a rear overhang predetermined threshold;

[0031] So that when executing step S1,

[0032] The inflation and deflation volume P1 of the front left airbag and the front right airbag is ΔH1*L1 / a;

[0033] The inflation and deflation volume P2 of the rear left airbag and the rear right airbag is ΔH1*L2 / a;

[0034] Wherein: ΔH1 is the difference between the front left airbag and / or the front right airbag and the front preset threshold; ΔH2 is the difference between the rear left airbag and / or the rear right airbag and the rear preset threshold; a is the cargo coefficient value of the truck.

[0035] As a preferred embodiment of the present invention, when executing step S1, specifically:

[0036] S11: The height valve obtains the suspension height;

[0037] S12: the airbag is inflated and deflated according to the inflation and deflation amount calculated by the suspension height;

[0038] S13: Determine whether the change in suspension height is greater than a fifth predetermined threshold value, if so, return to step S11; otherwise, the airbag adjustment is completed, and step S14 is executed;

[0039] S14: After the four airbags, namely the front left airbag, the front right airbag, the rear left airbag and the rear right airbag, are adjusted, the suspension height is stable.

[0040] As a preferred embodiment of the present invention, when executing steps S11 to S13, the four airbags are controlled and adjusted individually.

[0041] The beneficial effects of the heavy-load truck safe lifting method based on suspension signal of the present invention are:

[0042] During the lifting process of the cab compartment, the suspension signal analysis is performed on the suspension height of the front and rear suspension airbags, and the two stages before and after the cab compartment is separated from the rear suspension part are safely identified, further ensuring the safety of the compartment when it is raised, effectively preventing the cab compartment from overturning, and achieving high safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 The present invention is a schematic flow chart of a method for safely lifting a heavy-loaded truck based on a suspension signal. DETAILED DESCRIPTION

[0044] The following are specific embodiments of the present invention, which further describe the technical solutions of the present invention, but the present invention is not limited to these embodiments.

[0045] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that the relative arrangements of modules and structures set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise.

[0046] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

[0047] Technologies, methods, and systems known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and systems should be considered part of the authorization specification.

[0048] Embodiment 1: Figure 1 The figure is only one of the embodiments of the present invention, which is applicable to a heavy-duty truck safety lifting structure based on a suspension signal, including a front suspension part and a rear suspension part; the front suspension part includes a front suspension upper beam and a front suspension lower beam; the rear suspension part includes a rear suspension upper beam and a rear suspension lower beam; the front suspension upper beam and the front suspension lower beam are connected through a front suspension left airbag and a front suspension right airbag; the rear suspension upper beam and the rear suspension lower beam are connected through a rear suspension left airbag and a rear suspension right airbag; the front suspension left airbag, the front suspension right airbag, the rear suspension left airbag and the rear suspension right airbag are all provided with a height valve for obtaining the airbag suspension height; the rear suspension upper beam is provided with a lock buckle for connecting with the bottom beam of the cab;

[0049] The method comprises the following steps:

[0050] S1: When receiving a cab lift signal, the height valve obtains the airbag suspension height in real time; when the suspension height is greater than a first predetermined threshold, the cushion airbag is deflated; and when the suspension height is less than the first predetermined threshold, the cushion airbag is inflated until the suspension height is stable, and the cab is lifted by the cylinder;

[0051] In the present invention, when the new energy truck is started, that is, when the new energy truck needs to be used, if the cab compartment needs to be raised for maintenance and inspection, a cab compartment raising signal needs to be sent first.

[0052] Moreover, when the car body is not raised, the cab floor beam is stuck in the lock and locked by the locking valve in the lock. The locking valve is a hydraulic valve, which ensures the stable connection between the cab floor beam and the rear suspension assembly. The cab lifting signal is also a signal to unlock the hydraulic valve in the lock. Then, when executing step S1, it can be understood that: receiving the lock unlocking signal is a signal that the car body needs to be raised.

[0053] When executing step S1, if the cab compartment needs to be lifted, it is necessary to first adjust the current cab compartment suspension state. By adjusting the current suspension height of each airbag, the inflation and deflation of each airbag is adjusted individually to avoid the airbag suspension height being too high or too low. The current compartment is in the best suspension state before the cab compartment can be lifted.

[0054] After each airbag is inflated and deflated, the cab is lifted by the cylinder.

[0055] S2: determining whether the difference between the left suspension difference and the right suspension difference is not less than a third predetermined threshold before the suspension height of any one of the rear-suspended left airbag and the rear-suspended right airbag reaches the second predetermined threshold; if so, the cylinder stops lifting; otherwise, when the suspension height of any one of the rear-suspended left airbag and the rear-suspended right airbag reaches the second predetermined threshold, the lock is controlled to unlock, and step S3 is executed;

[0056] S3: Determine whether the difference between the left suspension differential rate and the right suspension differential rate is not less than a fourth predetermined threshold value; if so, the cylinder stops lifting; otherwise, no operation is performed, and the cylinder continues lifting until the cab is completely lifted.

[0057] It should be noted here that there are two stages in which the cylinder-driven cab compartment rises:

[0058] In the first stage, the rear suspension upper beam rises together with the rear end of the cab until it reaches the upper limit;

[0059] The second stage: After the rear suspension upper beam reaches the upper limit position, the lock opens and the rear suspension upper beam is separated from the rear end of the cab.

[0060] The rear suspension still has the support capability for lifting the cab compartment and can only be executed in the first stage; after entering the second stage, the rear suspension upper beam of the rear suspension is separated from the cab, and the rear suspension upper beam no longer provides support for the cab, and the rear suspension left airbag and rear suspension right airbag of the rear suspension both become unloaded (the mass of the rear suspension upper beam itself is negligible by default).

[0061] Moreover, the rear suspension upper beam reaches the upper limit position, which means that the suspension height of any one of the rear suspension left airbag and the rear suspension right airbag reaches a second predetermined threshold.

[0062] That is to say, the specific content of step S2 is: in the first stage of the cylinder driving the cab compartment to rise, if the difference between the left suspension difference and the right suspension difference is not less than the third predetermined threshold value, the cylinder stops lifting; otherwise, the lock is controlled to unlock when the rear suspension upper beam reaches the upper limit position.

[0063] At the same time, the specific content of step S3 is: in the second stage of the cylinder driving the cab compartment to lift, if the difference between the left suspension difference rate and the right suspension difference rate is not less than the fourth predetermined threshold value, the cylinder stops lifting; otherwise, no operation is performed, and the cylinder continues to lift until the cab is lifted.

[0064] In the present invention, when executing step S2, the suspension height difference between the front-suspended left airbag and the rear-suspended left airbag is calculated and recorded as the left-side suspension difference;

[0065] Calculate the difference in suspension height between the front right airbag and the rear right airbag, and record it as the right side suspension difference.

[0066] Then when executing step S2: specifically:

[0067] S21: acquiring a current left suspension difference and a current right suspension difference at a first predetermined time interval;

[0068] S22: Determine whether the difference between the left suspension difference and the right suspension difference is not less than a third predetermined threshold value, if so, stop executing the steps; otherwise, execute step S43;

[0069] S23: Determine whether the suspension height of any one of the rear-suspended left airbag and the rear-suspended right airbag reaches a second predetermined threshold, if so, control the lock to unlock; otherwise, return to step S41.

[0070] In the present invention, when executing step S3, the left suspension difference is divided by the suspension height value of the rear-suspended left airbag to obtain the left suspension difference rate;

[0071] Divide the right side suspension difference by the suspension height of the rear right airbag to obtain the right side suspension difference rate.

[0072] Then when executing step S3: specifically:

[0073] S31: acquiring the current left suspension difference rate and right suspension difference rate once every second predetermined time interval;

[0074] S32: Determine whether the difference between the left suspension differential rate and the right suspension differential rate is not less than a fourth predetermined threshold; if so, the cylinder stops lifting; otherwise, the cylinder continues lifting and executes step S33;

[0075] S33: Determine whether the cab is raised to a preset height; if so, the cab is raised and the cylinder stops lifting; otherwise, return to step S31.

[0076] The present invention provides a method for safely lifting the heavy-duty truck cabin based on suspension signals. During the process of raising the cab cabin, suspension signals of the suspension heights of the front suspension airbags and the rear suspension airbags are analyzed to safely identify the two stages before and after the cab cabin is separated from the rear suspension part, thereby further ensuring the safety of the cabin when it is raised, effectively preventing the cab cabin from overturning, and having high safety.

[0077] Embodiment 2: Still as Figure 1The figure is only one of the embodiments of the present invention. On the basis of the first embodiment, in a method for safely lifting a heavy-duty truck based on a suspension signal of the present invention, the left end of the front suspension upper beam and the left end of the front suspension lower beam are connected by a front suspension left airbag; the right end of the front suspension upper beam and the right end of the front suspension lower beam are connected by a front suspension right airbag; the left end of the rear suspension upper beam and the left end of the rear suspension lower beam are connected by a rear suspension left airbag; the right end of the rear suspension upper beam and the right end of the rear suspension lower beam are connected by a rear suspension right airbag;

[0078] The front-suspended left airbag and the front-suspended right airbag are symmetrically arranged; the rear-suspended left airbag and the rear-suspended right airbag are symmetrically arranged.

[0079] In one embodiment of the present invention, before executing step S1, the distance L1 between the front suspension left airbag and the front suspension right airbag and the center point of the front suspension upper beam is obtained; the distance L2 between the rear suspension left airbag and the rear suspension right airbag and the center point of the rear suspension upper beam is obtained;

[0080] The first predetermined threshold includes a front overhang predetermined threshold and a rear overhang predetermined threshold;

[0081] So that when executing step S1,

[0082] The inflation and deflation volume P1 of the front left airbag and the front right airbag is ΔH1*L1 / a;

[0083] The inflation and deflation volume P2 of the rear left airbag and the rear right airbag is ΔH1*L2 / a;

[0084] Wherein: ΔH1 is the difference between the front left airbag and / or the front right airbag and the front preset threshold; ΔH2 is the difference between the rear left airbag and / or the rear right airbag and the rear preset threshold; a is the cargo coefficient value of the truck.

[0085] In one embodiment of the present invention, when step S1 is performed, specifically:

[0086] S11: The height valve obtains the suspension height;

[0087] S12: the airbag is inflated and deflated according to the inflation and deflation amount calculated by the suspension height;

[0088] S13: Determine whether the change in suspension height is greater than a fifth predetermined threshold value, if so, return to step S11; otherwise, the airbag adjustment is completed, and step S14 is executed;

[0089] S14: After the four airbags, namely the front left airbag, the front right airbag, the rear left airbag and the rear right airbag, are adjusted, the suspension height is stable.

[0090] Here, when executing steps S11 to S13, the four airbags are controlled and adjusted individually.

[0091] It should be noted that when executing step S1: an electrical connection between the height valve and the lock is established, and the height valve is electrically connected to the lock through the controller.

[0092] When executing step S2, the lock is unlocked by controlling the controller.

[0093] The present invention provides a method for safely lifting the heavy-duty truck cabin based on suspension signals. During the process of raising the cab cabin, suspension signals of the suspension heights of the front suspension airbags and the rear suspension airbags are analyzed to safely identify the two stages before and after the cab cabin is separated from the rear suspension part, thereby further ensuring the safety of the cabin when it is raised, effectively preventing the cab cabin from overturning, and having high safety.

[0094] The present invention is not limited to the above specific implementations, and the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made to the above implementations based on the technical essence of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for safely lifting a heavy-duty truck based on a suspension signal, characterized in that: A heavy-duty truck safety lifting structure based on a suspension signal includes a front suspension part and a rear suspension part; the front suspension part includes a front suspension upper beam and a front suspension lower beam; the rear suspension part includes a rear suspension upper beam and a rear suspension lower beam; the front suspension upper beam and the front suspension lower beam are connected through a front suspension left airbag and a front suspension right airbag; the rear suspension upper beam and the rear suspension lower beam are connected through a rear suspension left airbag and a rear suspension right airbag; the front suspension left airbag, the front suspension right airbag, the rear suspension left airbag and the rear suspension right airbag are all provided with a height valve for obtaining the airbag suspension height; the rear suspension upper beam is provided with a lock buckle for connecting with the bottom beam of the cab; The method comprises the following steps: S1: When receiving a cab lift signal, the height valve obtains the airbag suspension height in real time; when the suspension height is greater than a first predetermined threshold, the cushion airbag is deflated; and when the suspension height is less than the first predetermined threshold, the cushion airbag is inflated until the suspension height is stable, and the cab is lifted by the cylinder; S2: determining whether the difference between the left suspension difference and the right suspension difference is not less than a third predetermined threshold before the suspension height of any one of the rear-suspended left airbag and the rear-suspended right airbag reaches the second predetermined threshold; if so, the cylinder stops lifting; otherwise, when the suspension height of any one of the rear-suspended left airbag and the rear-suspended right airbag reaches the second predetermined threshold, the lock is controlled to unlock, and step S3 is executed; S3: Determine whether the difference between the left suspension differential rate and the right suspension differential rate is not less than a fourth predetermined threshold value; if so, the cylinder stops lifting; otherwise, no operation is performed until the cab is completely lifted.

2. A method for safely lifting a heavy-loaded truck based on a suspension signal according to claim 1, characterized in that: When executing step S2, the suspension height difference between the front left airbag and the rear left airbag is calculated and recorded as the left suspension difference; Calculate the difference in suspension height between the front right airbag and the rear right airbag, and record it as the right side suspension difference.

3. A method for safely lifting a heavy-duty truck based on a suspension signal according to claim 2, characterized in that: When executing step S2: specifically: S21: acquiring a current left suspension difference and a current right suspension difference at a first predetermined time interval; S22: Determine whether the difference between the left suspension difference and the right suspension difference is not less than a third predetermined threshold value, if so, stop executing the steps; otherwise, execute step S43; S23: Determine whether the suspension height of any one of the rear-suspended left airbag and the rear-suspended right airbag reaches a second predetermined threshold, if so, control the lock to unlock; otherwise, return to step S41.

4. A method for safely lifting a heavy-loaded truck based on a suspension signal according to claim 2, characterized in that: When executing step S3, the left side suspension difference is divided by the suspension height value of the rear-suspended left airbag to obtain the left side suspension difference rate; Divide the right side suspension difference by the suspension height of the rear right airbag to obtain the right side suspension difference rate.

5. A method for safely lifting a heavy-loaded truck based on a suspension signal according to claim 4, characterized in that: When executing step S3: specifically: S31: acquiring the current left suspension difference rate and right suspension difference rate once every second predetermined time interval; S32: Determine whether the difference between the left suspension differential rate and the right suspension differential rate is not less than a fourth predetermined threshold; if so, the cylinder stops lifting; otherwise, the cylinder continues lifting and executes step S33; S33: Determine whether the cab is raised to a preset height; if so, the cab is raised and the cylinder stops lifting; otherwise, return to step S31.

6. A method for safely lifting a heavy-loaded truck based on a suspension signal according to claim 1, characterized in that: When executing step S1: establishing an electrical connection between the height valve and the lock buckle, the height valve is electrically connected to the lock buckle through the controller; When executing step S2, the lock is unlocked by controlling the controller.

7. The method for safely lifting a heavy-loaded truck based on a suspension signal according to claim 1, characterized in that: The left end of the front suspension upper beam and the left end of the front suspension lower beam are connected by a front suspension left airbag; the right end of the front suspension upper beam and the right end of the front suspension lower beam are connected by a front suspension right airbag; the left end of the rear suspension upper beam and the left end of the rear suspension lower beam are connected by a rear suspension left airbag; the right end of the rear suspension upper beam and the right end of the rear suspension lower beam are connected by a rear suspension right airbag; The front-suspended left airbag and the front-suspended right airbag are symmetrically arranged; the rear-suspended left airbag and the rear-suspended right airbag are symmetrically arranged.

8. The method for safely lifting a heavy-loaded truck based on a suspension signal according to claim 1 is characterized in that: Before executing step S1, obtain the distance L1 between the front suspension left airbag and the front suspension right airbag and the center point of the front suspension upper beam; obtain the distance L2 between the rear suspension left airbag and the rear suspension right airbag and the center point of the rear suspension upper beam; The first predetermined threshold includes a front overhang predetermined threshold and a rear overhang predetermined threshold; So that when executing step S1, The inflation and deflation volume P1 of the front left airbag and the front right airbag is ΔH1*L1 / a; The inflation and deflation volume P2 of the rear left airbag and the rear right airbag is ΔH1*L2 / a; Wherein: ΔH1 is the difference between the front left airbag and / or the front right airbag and the front preset threshold; ΔH2 is the difference between the rear left airbag and / or the rear right airbag and the rear preset threshold; a is the cargo coefficient value of the truck.

9. A method for safely lifting a heavy-loaded truck based on a suspension signal according to claim 8, characterized in that: When executing step S1, specifically: S11: The height valve obtains the suspension height; S12: the airbag is inflated and deflated according to the inflation and deflation amount calculated by the suspension height; S13: Determine whether the change in suspension height is greater than a fifth predetermined threshold value, if so, return to step S11; otherwise, the airbag adjustment is completed, and step S14 is executed; S14: After the four airbags, namely the front left airbag, the front right airbag, the rear left airbag and the rear right airbag, are adjusted, the suspension height is stable.

10. A method for safely lifting a heavy-loaded truck based on a suspension signal according to claim 9, characterized in that: When executing steps S11 to S13, the four airbags are controlled and adjusted individually.

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