A starting control method of an 8AMT commercial vehicle

Abstract

The application discloses a starting control method of an 8AMT commercial vehicle and relates to the technical field of commercial vehicles, and comprises the following steps: when the vehicle starts, the current vehicle total mass is acquired, the current road slope value is acquired, and the continuous ignition-off duration before the vehicle starts is acquired; if the continuous ignition-off duration before the vehicle starts exceeds a first preset duration, before the current vehicle total mass is acquired, and when the vehicle is in the D gear, the starting gear of the vehicle is controlled by a TCU according to the current road slope value; after the current vehicle total mass is acquired, the starting gear of the vehicle is controlled by the TCU according to the current vehicle total mass and the current road slope value. The power performance of the vehicle is fully exerted, the clutch and the gear of the transmission are protected, the reliability of the vehicle is ensured, and smooth and smooth starting can be realized. Meanwhile, the intelligent degree of the 8AMT commercial vehicle is improved.

Description

Technical Field

[0001] This invention relates to the field of commercial vehicle technology, and specifically to a starting control method for an 8AMT commercial vehicle. Background Technology

[0002] Currently, 8AMT commercial vehicles do not have intelligent gear selection for starting. Instead, they control the starting gear by adding a 1 / 2 gear selection to the electronic shifter. For different vehicle loads and gradients, the inability to reasonably select the appropriate gear for starting can affect the clutch life and may cause gear grinding. Summary of the Invention

[0003] This application provides a starting control method for an 8AMT commercial vehicle to at least solve one technical problem existing in the related art.

[0004] The starting control method for the 8AMT commercial vehicle includes: when the vehicle starts, obtaining the current total vehicle mass, obtaining the current road gradient value, and obtaining the continuous engine shutdown duration before the vehicle starts; if the continuous engine shutdown duration before the vehicle starts exceeds a first preset duration, before obtaining the current total vehicle mass and when the vehicle is in D gear, the TCU controls the starting gear of the vehicle according to the current road gradient value; after obtaining the current total vehicle mass, the TCU controls the starting gear of the vehicle according to the current total vehicle mass and the current road gradient value.

[0005] As an optional implementation, if the duration of the vehicle's continuous shutdown before starting is less than the first preset duration, the TCU controls the vehicle to drive in the starting gear of the vehicle before the last shutdown.

[0006] As an optional implementation, it further includes: if the continuous shutdown time before the vehicle starts is less than the first preset time, determining whether the difference between the current total vehicle mass and the total vehicle mass before the previous shutdown is greater than a preset mass difference; if the difference between the current total vehicle mass and the total vehicle mass before the previous shutdown is greater than the preset mass difference, the TCU determines the starting gear of the vehicle based on the current total vehicle mass and the current road slope value.

[0007] As an optional implementation, it further includes: if the difference between the current total vehicle mass and the total vehicle mass before the vehicle was turned off is less than a preset mass difference, the TCU controls the vehicle to drive in the starting gear of the vehicle before the previous engine was turned off.

[0008] As an optional implementation, if the continuous shutdown time before the vehicle starts exceeds a first preset time, before obtaining the current total vehicle mass, and when the vehicle's starting gear is in D gear, the TCU controls the vehicle's starting gear according to the current road slope value, including: determining whether the current road slope value is greater than a first preset slope value; if the current road slope value is greater than the first preset slope value, the TCU controls the vehicle to start in 1st gear.

[0009] As an optional implementation, if the continuous shutdown time before the vehicle starts exceeds a first preset time, and before the current total mass of the vehicle is obtained, and the vehicle's starting gear is in D gear, the TCU controls the vehicle's starting gear according to the current road slope value, which further includes: if the current road slope value is less than the first preset slope value, the TCU controls the vehicle to start in 2nd gear.

[0010] As an optional implementation, it also includes: if a manual shift signal is obtained when the TCU controls the starting gear of the vehicle, then the starting gear of the vehicle is controlled according to the manual shift signal.

[0011] As an optional implementation, it also includes: if the current road gradient value is greater than a second preset gradient value, the EPB automatically connects to vehicle control.

[0012] As an optional implementation, if the current road gradient value is greater than the second preset gradient value, the EPB automatically connects to vehicle control, including: when the vehicle speed signal and the output shaft speed signal are both 0 and the throttle opening is ≥5%, the TCU sends a release command to the EPB, the EPB controls the brake to lock the motor, the TCU controls the clutch to slip, and controls the engine to increase torque.

[0013] This application provides a starting control method for an 8AMT commercial vehicle, comprising: when starting the vehicle, acquiring the current total vehicle mass, acquiring the current road gradient, and acquiring the continuous engine shutdown duration before starting the vehicle; if the continuous engine shutdown duration before starting the vehicle exceeds a first preset duration, before acquiring the current total vehicle mass and while the vehicle is in D gear, the TCU controls the starting gear of the vehicle based on the current road gradient; after acquiring the current total vehicle mass, the TCU controls the starting gear of the vehicle based on the current total vehicle mass and the current road gradient. For commercial vehicles, due to large variations in load, starting in first gear when the vehicle is unloaded is too slow; starting in a lower gear at a higher speed can easily damage the clutch. Therefore, it is crucial to rationally select the starting gear based on different loads and gradients. 8AMT commercial vehicles have multiple gears, and a reasonable starting gear can fully utilize the vehicle's power, protect the clutch and transmission gears, ensure vehicle reliability, and achieve a smooth start. This also improves the intelligence level of the 8AMT commercial vehicle. Attached Figure Description

[0014] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic flowchart of a starting control method for an 8AMT commercial vehicle provided according to an embodiment of this application. Detailed Implementation

[0017] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0018] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0019] like Figure 1 As shown in the figure, this application provides a starting control method for an 8AMT commercial vehicle, including:

[0020] When the vehicle starts, S1 obtains the current total mass of the vehicle, the current road gradient, and the duration of the engine shutdown before the vehicle starts.

[0021] S2 If the duration of the vehicle's continuous shutdown before starting exceeds the first preset duration, before obtaining the current total mass of the vehicle, and when the vehicle is in D gear, the TCU controls the starting gear of the vehicle based on the current road gradient value.

[0022] After obtaining the current total vehicle mass, the TCU controls the starting gear of the vehicle based on the current total vehicle mass and the current road gradient.

[0023] For commercial vehicles, due to significant variations in load, starting in first gear when the vehicle is unloaded is too slow, while starting in a higher gear with a lower speed can damage the clutch. Therefore, it is crucial to select the appropriate starting gear based on different loads and inclines. 8AMT commercial vehicles offer multiple gears, and a suitable starting gear will fully utilize the vehicle's power while protecting the clutch and transmission gears, ensuring vehicle reliability, and achieving a smooth start. This also enhances the intelligence of 8AMT commercial vehicles.

[0024] Specifically, it is easy to understand that it takes a certain amount of time to determine the total weight of the vehicle. Therefore, before the current total vehicle weight is obtained, and when the vehicle is in D gear, the TCU controls the starting gear of the vehicle based on the current road slope value. After the current total vehicle weight is obtained, the TCU controls the starting gear of the vehicle based on the current total vehicle weight and the current road slope value.

[0025] Furthermore, the first preset time duration can be determined based on vehicle usage habits, cargo loading conditions, and other factors. For example, if the unloading time for a fully loaded vehicle is approximately half an hour, the first preset time duration can be set to half an hour. If the engine is off for more than half an hour, it can be assumed that the vehicle was turned off for unloading, resulting in a significant change in the vehicle's total mass. Therefore, before obtaining the current total vehicle mass and while the vehicle is in Drive (D) gear, the TCU controls the starting gear based on the current road gradient. After obtaining the current total vehicle mass, the TCU controls the starting gear based on both the current total vehicle mass and the current road gradient. This is equivalent to restarting the vehicle based on its operating conditions.

[0026] Furthermore, the specific implementation method of the TCU controlling the starting gear of the vehicle based on the current total vehicle mass and the current road slope value can be determined according to Table 1: Relationship Table of Slope, Load and Starting Gear. Table 1 can be calibrated when the vehicle leaves the factory, and this application does not limit it.

[0027] Table 1: Relationship between Gradient, Load Capacity, and Starting Gear

[0028]

[0029] As an optional implementation, if the duration of the vehicle's continuous shutdown before starting is less than the first preset duration, the TCU controls the vehicle to drive in the starting gear of the vehicle before the last shutdown.

[0030] Specifically, if the vehicle stalls and restarts within the first preset time period, that is, the stall duration before starting is less than the first preset time period, then the vehicle has most likely not performed an unloading operation. In this case, it can be assumed that the total mass of the vehicle has not changed, so start directly in the starting gear used in the previous start.

[0031] As an optional implementation, it further includes: if the continuous shutdown time before the vehicle starts is less than the first preset time, determining whether the difference between the current total vehicle mass and the total vehicle mass before the previous shutdown is greater than a preset mass difference; if the difference between the current total vehicle mass and the total vehicle mass before the previous shutdown is greater than the preset mass difference, the TCU determines the starting gear of the vehicle based on the current total vehicle mass and the current road slope value.

[0032] Specifically, it is understandable that if a vehicle stops and starts again within a first preset time period, it may be because some cargo has been unloaded. Therefore, the total mass of the vehicle may change significantly. Thus, it is also possible to determine whether the difference between the current total mass of the vehicle and the total mass of the vehicle before the last time it was stopped is greater than a preset mass difference. If the difference between the current total mass of the vehicle and the total mass of the vehicle before the last time it was stopped is greater than the preset mass difference, the TCU determines the starting gear of the vehicle based on the current total mass of the vehicle and the current road gradient.

[0033] As an optional implementation, it further includes: if the difference between the current total vehicle mass and the total vehicle mass before the vehicle was turned off is less than a preset mass difference, the TCU controls the vehicle to drive in the starting gear of the vehicle before the previous engine was turned off.

[0034] As an optional implementation, if the continuous shutdown time before the vehicle starts exceeds a first preset time, before obtaining the current total vehicle mass, and when the vehicle's starting gear is in D gear, the TCU controls the vehicle's starting gear according to the current road slope value, including: determining whether the current road slope value is greater than a first preset slope value; if the current road slope value is greater than the first preset slope value, the TCU controls the vehicle to start in 1st gear.

[0035] Specifically, the first preset slope value can be determined based on the vehicle's operating conditions, for example, it can be set to 10°. Simultaneously, the slope value can be set to positive or negative values. For example, if the road ahead is uphill, the slope value can be considered positive; if the road ahead is downhill, the slope value can be considered negative. When the current road slope value is greater than 10°, meaning the vehicle needs to start uphill, it starts in first gear.

[0036] As an optional implementation, if the continuous shutdown time before the vehicle starts exceeds a first preset time, and before the current total mass of the vehicle is obtained, and the vehicle's starting gear is in D gear, the TCU controls the vehicle's starting gear according to the current road slope value, which further includes: if the current road slope value is less than the first preset slope value, the TCU controls the vehicle to start in 2nd gear.

[0037] If the current road gradient is less than the first preset gradient, the vehicle will start in second gear.

[0038] As an optional implementation, it also includes: if a manual shift signal is obtained when the TCU controls the starting gear of the vehicle, then the starting gear of the vehicle is controlled according to the manual shift signal.

[0039] As an optional implementation, it also includes: if the current road gradient value is greater than a second preset gradient value, the EPB automatically connects to vehicle control.

[0040] As an optional implementation, if the current road gradient value is greater than the second preset gradient value, the EPB automatically connects to vehicle control, including: when the vehicle speed signal and the output shaft speed signal are both 0 and the throttle opening is ≥5%, the TCU sends a release command to the EPB, the EPB controls the brake to lock the motor, the TCU controls the clutch to slip, and controls the engine to increase torque.

[0041] This application is for a control system based on CAN control for an 8AMT commercial vehicle with intelligent starting gear selection, including an automatic transmission control system TCU; shift lever SCU, engine ECU, accelerator pedal, brake pedal, clutch, instrument cluster IC, EPB electronic control unit, ABS and other components.

[0042] The sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0043] If the integrated units in the above embodiments are implemented as software functional units and sold or used as independent products, they can be stored in the aforementioned computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause one or more electronic devices (which may be personal computers, servers, or network devices, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application.

[0044] In the above embodiments of this application, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0045] In the several embodiments provided in this application, it should be understood that the disclosed client can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces, indirect coupling or communication connection between units or modules, and may be electrical or other forms.

[0046] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of the solution provided in this embodiment, depending on actual needs.

[0047] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0048] In the above embodiments of this application, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0049] The above description is only a preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A starting control method of an 8AMT commercial vehicle, characterized in that, Comprise: When the vehicle starts, the current vehicle total mass is obtained, the current road slope value is obtained, and the continuous engine-off duration before the vehicle starts is obtained; If the continuous engine-off duration before the vehicle starts exceeds the first preset duration, before the current vehicle total mass is obtained, and the vehicle is in D range, the TCU controls the starting gear of the vehicle according to the current road slope value; After the current vehicle total mass is obtained, the TCU controls the starting gear of the vehicle according to the current vehicle total mass and the current road slope value; If the continuous engine-off duration before the vehicle starts is less than the first preset duration, the TCU controls the vehicle to drive in the starting gear before the previous engine-off of the vehicle; If the continuous engine-off duration before the vehicle starts is less than the first preset duration, it is judged whether the difference between the current vehicle total mass and the vehicle total mass before the previous engine-off of the vehicle is greater than a preset mass difference; If the difference between the current vehicle total mass and the vehicle total mass before the previous engine-off of the vehicle is greater than the preset mass difference, the TCU determines the starting gear of the vehicle according to the current vehicle total mass and the current road slope value; If the difference between the current vehicle total mass and the vehicle total mass before the previous engine-off of the vehicle is less than the preset mass difference, the TCU controls the vehicle to drive in the starting gear before the previous engine-off of the vehicle.

2. The starting control method of the 8AMT commercial vehicle as claimed in claim 1, wherein, The TCU controls the starting gear of the vehicle according to the current road slope value if the continuous engine-off duration before the vehicle starts exceeds the first preset duration, before the current vehicle total mass is obtained, and the vehicle is in D range, comprising: It is judged whether the current road slope value is greater than a first preset slope value; If the current road slope value is greater than the first preset slope value, the TCU controls the vehicle to start in 1st gear.

3. The starting control method of the 8AMT commercial vehicle as claimed in claim 2, wherein, The TCU controls the starting gear of the vehicle according to the current road slope value if the continuous engine-off duration before the vehicle starts exceeds the first preset duration, before the current vehicle total mass is obtained, and the vehicle is in D range, further comprising: If the current road slope value is less than the first preset slope value, the TCU controls the vehicle to start in 2nd gear.

4. The starting control method of the 8AMT commercial vehicle as claimed in claim 1, wherein, Further comprising: If a manual gear shifting signal is obtained when the TCU controls the starting gear of the vehicle, the starting gear of the vehicle is controlled according to the manual gear shifting signal.

5. The starting control method of the 8AMT commercial vehicle as claimed in claim 1, wherein, Further comprising: If the current road slope value is greater than a second preset slope value, the EPB automatically accesses the vehicle control.

6. The starting control method of the 8AMT commercial vehicle as claimed in claim 5, wherein, The EPB automatically accesses the vehicle control if the current road slope value is greater than a second preset slope value, comprising: When the vehicle speed signal and the output shaft speed signal are both 0 and the accelerator opening degree is greater than or equal to 5%, the TCU sends a release instruction to the EPB, the EPB controls the brake locking motor, the TCU controls the clutch slip, and the engine torque is increased.

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