Methods for avoiding abnormal vibration speed in non-working section

Abstract

The present invention discloses a method for avoiding abnormal vibration speed in a non-working section, which belongs to the technical field of engineering machinery. The method solves the defects of high design cost and production cost in the conventional method for avoiding abnormal vibration in a non-working section in the prior art. The main structure includes inputting the abnormal vibration speed section, the original state instruction, and the abnormal vibration state avoidance instruction into the vehicle electronic control unit (VECU). After startup, the whole machine executes the original state instruction by default, assigns a value of 0s to the timer t in the abnormal vibration speed section, and the operator steps on the accelerator pedal. The inclinometer measures the stepping angle of the accelerator pedal, and the vehicle electronic control unit (VECU) collects the stepping angle of the inclinometer and sends an instruction to the engine electronic control unit (ECU). The engine outputs the speed. At the same time, the vehicle electronic control unit (VECU) collects the pressure of the working device hydraulic cylinder by the pressure sensor and judges whether it is in a load working state. The present invention is mainly used in engineering machinery.

Description

Technical field:

[0001] The present invention belongs to the technical field of engineering machinery, and in particular relates to a method for avoiding abnormal vibration speed in a non-working section. Background technology:

[0002] As modern construction equipment, construction machinery is widely used in transportation, energy development, construction, mining, agriculture, forestry, and water conservancy projects. Due to their harsh operating conditions, construction machinery generates high noise and vibration, severely impacting its lifespan. Abnormal vibration, in particular, not only compromises overall strength and creates excessive noise, but also severely impacts the driver's driving experience, significantly hindering product competitiveness. However, abnormal vibration is unavoidable. When the frequency of the excitation applied to the machine approaches a certain natural frequency of the construction machinery, the system amplitude increases significantly, a phenomenon known as abnormal vibration. Consequently, the entire construction machinery industry is investing significant resources to minimize the impact of vibration. Vibration control typically involves controlling the source of vibration and isolating the vibration. Vibration source control involves modifying engine design parameters to adjust the system's natural frequency, typically by increasing system damping. Vibration isolation involves reducing vibration response using dynamic vibration absorbers, such as rubber isolation, spiral wire rope isolation, and hydraulic isolation.

[0003] Abnormal vibration generally needs to be controlled from the outset. Modifying the existing structure of construction machinery, such as changing engine design parameters, means that each engine model needs to be individually designed, increasing both design and production costs. For many construction machinery manufacturers that outsource their engines, coordinating joint development requires significant investment in manpower and resources. Increasing system damping to adjust the system's natural frequency also requires changes to the design assembly drawings, further wasting manpower and resources. Due to the high vibration levels in the working environment of construction machinery, operators generally don't pay much attention to vibration issues during operation. Therefore, vibration issues during non-operational periods require even greater attention. Summary of the invention:

[0004] The technical problem to be solved by the present invention is to overcome the shortcomings of the existing technology and provide a method for avoiding abnormal vibration speed in the non-working section. Since the abnormal vibration speed section in the non-working section is avoided, the negative impact of vibration is reduced, the operator's driving experience is improved, and the product competitiveness is enhanced.

[0005] In order to achieve the above object, the present invention is implemented by adopting the following technical solutions:

[0006] A method for avoiding abnormal vibration speed in a non-working section includes the following steps:

[0007] S1: Before starting, the abnormal vibration speed range, original state command, and abnormal vibration avoidance state command are input into the vehicle electronic control unit (VECU). After startup, the entire vehicle executes the original state command by default, and the timer t in the abnormal vibration speed range is assigned a value of 0s.

[0008] S2: The operator presses the accelerator pedal, and the inclinometer measures the accelerator pedal's depression angle. The vehicle electronic control unit (VECU) collects the inclinometer's depression angle and sends a command to the engine electronic control unit (ECU) to control the engine output speed. At the same time, the vehicle electronic control unit (VECU) collects the pressure sensor's pressure on the hydraulic cylinder of the working device and determines whether it is in a load working state. If so, the program is not intervened, the original state command is executed, and step S2 is continued. If not, step S3 is entered.

[0009] S3: Determine whether the engine speed is lower than the abnormal vibration speed range. If the engine speed is lower than the abnormal vibration speed range, do not intervene in the program, execute the original state instruction, and return to step S2. If the engine speed is not lower than the abnormal vibration speed range, proceed to step S4.

[0010] S4: Determine whether the engine speed is in the abnormal vibration speed section. If the engine speed is not in the abnormal vibration speed section, determine whether the current instruction is executing the original state instruction. If the current instruction is executing the original state instruction, continue to execute the original state instruction and return to step S2. If the current instruction is not executing the original state instruction, enter step S5 and then return to step S2. If the engine speed is in the abnormal vibration speed section, start timer t, and then determine whether the time in the abnormal vibration speed section is greater than the acceptable time coefficient t0. If t≥t0, enter step S5 and then return to step S2. If t<t0, continue to execute the original state instruction and return to step S2.

[0011] S5: Execute the instruction to avoid the abnormal vibration state, and output the speed n to jump out of the abnormal vibration speed section.

[0012] Preferably, the original state instruction is an instruction containing a positive proportional relationship between the accelerator pedal depression depth and the engine speed value. Under normal circumstances, the positive proportional relationship between the accelerator pedal depression depth and the engine speed value is:

[0013] n=k(α-α0)

[0014] Where α0 is the initial angle when the accelerator pedal starts to respond, α is the angle when the accelerator pedal is depressed, n is the engine speed, and k is the proportional coefficient between the accelerator pedal depression depth and the engine speed value.

[0015] Preferably, the abnormal vibration avoidance state instruction is an instruction containing a non-proportional relationship between the accelerator pedal depression depth and the engine speed value during abnormal vibration. The non-proportional relationship between the accelerator pedal depression depth and the engine speed value during abnormal vibration is:

[0016] n=k′(α+α T -α0)

[0017] Among them, α T In order to skip the angle corresponding to the speed, k′ is the new proportional coefficient between the accelerator pedal depression depth and the engine speed value when t≥t0.

[0018] Preferably, the value of k' is:

[0019]

[0020] Among them, n max is the maximum engine speed, n2 is the engine speed when the abnormal vibration ends, α max is the maximum angle of the accelerator pedal, and α2 is the angle of the accelerator pedal when the abnormal vibration ends.

[0021] Preferably, the α T The value of is:

[0022] α T =α2-α1

[0023] Here, α1 is the angle of the accelerator pedal when the abnormal vibration starts.

[0024] Preferably, the value range of the abnormal vibration speed segment is [n1, n2], wherein n1 is the speed of the engine when the abnormal vibration starts, and n2 is the speed of the engine when the abnormal vibration ends.

[0025] Preferably, the inclinometer is mounted on the accelerator pedal.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] 1. The present invention uses a pressure sensor to collect the pressure in the hydraulic cylinder of the working device to determine whether it is working under load, and only avoids abnormal vibration in the non-working state, avoiding the waste of time and cost caused by changing the existing structure, while also ensuring the safety and reliability of the engine when working under load;

[0028] 2. Since abnormal vibration speed sections in non-working sections are avoided, the negative impact of vibration is reduced, the operator's driving experience is improved, and the product competitiveness is enhanced;

[0029] 3. The present invention is simple in structure and can avoid abnormal vibration speed section in non-working section by simply adding pressure sensor and inclinometer, and the cost is low. Description of the drawings:

[0030] Figure 1 is a flow chart of the present invention;

[0031] Figure 2 Schematic diagram of the installation structure of each component in the present invention;

[0032] Figure 3 It is a structural block diagram of the present invention;

[0033] Figure 4 The corresponding relationship between the engine output speed and the accelerator pedal angle under normal conditions in the present invention;

[0034] Figure 5 This is the corresponding relationship between the engine output speed and the accelerator pedal angle in the case of abnormal vibration jump in the present invention.

[0035] In the figure: 1. Pressure sensor; 2. Angle meter; 3. Accelerator pedal; 4. Vehicle electronic control unit (VECU); 5. Engine electronic control unit (ECU). Specific implementation method:

[0036] The present invention will be further described below through specific embodiments in conjunction with the accompanying drawings.

[0037] Example 1:

[0038] like Figure 1-3 As shown, a method for avoiding abnormal vibration speed in a non-working section includes the following steps:

[0039] S1: Before starting, the abnormal vibration speed range, original state instruction, and abnormal vibration avoidance state instruction are input into the vehicle electronic control unit VECU4. After startup, the whole vehicle executes the original state instruction by default, and the timer t in the abnormal vibration speed range is assigned a value of 0s;

[0040] S2: The operator presses down the accelerator pedal 3, and the inclinometer 2 measures the pressing angle of the accelerator pedal 3. The vehicle electronic control unit VECU4 collects the pressing angle of the inclinometer 2 and sends a command to the engine electronic control unit ECU5, which outputs the engine speed. At the same time, the vehicle electronic control unit VECU4 collects the pressure of the working device hydraulic cylinder from the pressure sensor 1 and determines whether it is in a load working state. If it is in a load working state, the program is not intervened, the original state instruction is executed, and the process continues to S2. If it is not in a load working state, the process proceeds to step S3.

[0041] The function of the pressure sensor 1 is to collect the pressure in the hydraulic cylinder of the working device through the pressure sensor 1 and send the information to the vehicle electronic control unit VECU4;

[0042] S3: Determine whether the engine speed is lower than the abnormal vibration speed range. If the engine speed is lower than the abnormal vibration speed range, do not intervene in the program, execute the original state instruction, and return to step S2. If the engine speed is not lower than the abnormal vibration speed range, proceed to step S4.

[0043] S4: Determine whether the engine speed is in the abnormal vibration speed section. If the engine speed is not in the abnormal vibration speed section, determine whether the current instruction is executing the original state instruction. If the current instruction is executing the original state instruction, continue to execute the original state instruction and return to step S2. If the current instruction is not executing the original state instruction, enter step S5 and then return to step S2. If the engine speed is in the abnormal vibration speed section, the timer t starts timing, and then determines whether the time in the abnormal vibration speed section is greater than the acceptable time coefficient t0. If t≥t0, enter step S5 and then return to step S2. If t<t0, continue to execute the original state instruction and return to step S2, where t0 is the operator's acceptable time coefficient, generally less than 1s, and the specific value depends on the actual situation.

[0044] S5: Execute the instruction to avoid the abnormal vibration state, and output the speed n to jump out of the abnormal vibration speed section.

[0045] What needs to be explained about Example 1 is:

[0046] Since the abnormal vibration of the whole machine is determined by the natural frequency of the whole machine and the vibration frequency of the engine, the abnormal vibration speed range of each model is different, but the abnormal vibration speed range of each model is the same. Vibration testing will be carried out during the whole machine design stage. At this time, the abnormal vibration speed range can be found in advance and imported into the vehicle electronic control unit VECU4;

[0047] There are generally two ways to reach the abnormal vibration frequency range, namely speed increase and speed decrease, but the following two situations cannot be intervened:

[0048] Situation 1: When the bucket is shoveling materials, the engine speed increases and abnormal vibration may occur. Do not interfere with the speed change at this time, because interfering with the engine speed at this time may cause engine failure;

[0049] Case 2: After shoveling, when the boom is lifted, the engine power remains unchanged, but the increased load causes the engine torque to increase. At this time, the engine will slow down, and abnormal vibration may also occur. The speed at this time cannot be intervened, because the abnormal change in speed may cause safety problems such as arm drop and flameout, and the speed drop time is short, so most operators will not pay attention to it.

[0050] Although the abnormal vibration speed section cannot be intervened during load operation, due to the noisy working environment of the construction machinery itself and the large vibration amplitude of the shoveling operation, the operator often pays little attention to the abnormal vibration of the engine; the above situations have one thing in common, that is, there is a load at this time and the hydraulic cylinder has pressure. The status of the hydraulic cylinder can be judged based on whether there is a load.

[0051] Therefore, the present invention mainly focuses on the following situations:

[0052] When the operator simulates the operation or stands still, he slowly steps on or releases the accelerator pedal 3 to slowly increase or decrease the engine speed. At this time, since the working environment of the whole machine is relatively quiet and the vibration is small, once abnormal vibration occurs, the operator can easily feel it, affecting the operating experience. Since there is no load in this situation, the abnormal change in speed will not affect the performance of the whole machine. Therefore, the present invention avoids this speed segment. In order to achieve abnormal speed avoidance, the method adopted is to skip the abnormal vibration speed segment.

[0053] Example 2:

[0054] A method for avoiding abnormal vibration speed in a non-working section, wherein the original state instruction is an instruction containing a positive proportional relationship between the accelerator pedal 3 depression depth and the engine speed value. Under normal circumstances, the positive proportional relationship between the accelerator pedal 3 depression depth and the engine speed value is:

[0055] n=k(α-α0)

[0056] Wherein, α0 is the initial angle when the accelerator pedal 3 starts to respond, α is the angle when the accelerator pedal 3 is depressed, n is the engine speed, and k is the proportional coefficient between the depression depth of the accelerator pedal 3 and the engine speed value.

[0057] The abnormal vibration avoidance state instruction is an instruction containing a non-proportional relationship between the accelerator pedal 3 depression depth and the engine speed value during abnormal vibration. The non-proportional relationship between the accelerator pedal 3 depression depth and the engine speed value during abnormal vibration is:

[0058] n=k′(α+α T -α0)

[0059] Among them, α TIn order to skip the angle corresponding to the speed, k′ is the new proportional coefficient between the accelerator pedal 3 depression depth and the engine speed value when t≥t0. The proportional coefficient between the accelerator pedal 3 depression depth and the engine speed value is changed to ensure that the maximum speed of the engine remains unchanged under the original state instruction and the abnormal vibration avoidance state instruction. Figure 4-5 It can be seen.

[0060] The value of k' is:

[0061]

[0062] Among them, n max is the maximum engine speed, n2 is the engine speed when the abnormal vibration ends, α max is the maximum angle of the accelerator pedal 3, and α2 is the angle of the accelerator pedal 3 when the abnormal vibration ends.

[0063] The α T The value of is:

[0064] α T =α2-α1

[0065] Here, α1 is the angle of the accelerator pedal 3 when the abnormal vibration starts.

[0066] The value range of the abnormal vibration speed segment is [n1, n2], wherein n1 is the engine speed when the abnormal vibration starts, and n2 is the engine speed when the abnormal vibration ends.

[0067] The inclinometer 2 is mounted on the accelerator pedal 3 and is used to measure the depression angle of the accelerator pedal 3. Other parts are the same as those in embodiment 1.

Claims

1. A method for avoiding abnormal vibration speed in a non-working section, characterized by: The following steps are involved: S1: Before starting, the abnormal vibration speed section, the original state instruction, and the abnormal vibration avoidance state instruction are input into the vehicle electronic control unit VECU (4). After starting, the whole vehicle executes the original state instruction by default, and the timer t in the abnormal vibration speed section is assigned a value of 0s; S2: The operator steps on the accelerator pedal (3), the inclinometer (2) measures the angle of the accelerator pedal (3), the vehicle electronic control unit (VECU) (4) collects the angle of the inclinometer (2) and sends a command to the engine electronic control unit (ECU) (5), the engine outputs the speed, and at the same time the vehicle electronic control unit (VECU) (4) collects the pressure of the hydraulic cylinder of the working device from the pressure sensor (1) and judges whether it is in a load working state. If it is in a load working state, the program is not intervened, the original state command is executed, and step S2 is continued. If it is not in a load working state, step S3 is entered; S3: Determine whether the engine speed is lower than the abnormal vibration speed range. If the engine speed is lower than the abnormal vibration speed range, do not intervene in the program, execute the original state instruction, and return to step S2. If the engine speed is not lower than the abnormal vibration speed range, proceed to step S4. S4: Determine whether the engine speed is in the abnormal vibration speed section. If the engine speed is not in the abnormal vibration speed section, determine whether the current instruction is executing the original state instruction. If the current instruction is executing the original state instruction, continue to execute the original state instruction and return to step S2. If the current instruction is not executing the original state instruction, enter step S5 and then return to step S2. If the engine speed is in the abnormal vibration speed section, start timer t, and then determine whether the time in the abnormal vibration speed section is greater than the acceptable time coefficient t0. If t≥t0, enter step S5 and then return to step S2. If t<t0, continue to execute the original state instruction and return to step S2. S5: Execute the instruction to avoid the abnormal vibration state, and output the speed n to jump out of the abnormal vibration speed section; The abnormal vibration avoidance state instruction is an instruction containing an instruction that the accelerator pedal (3) is pressed down with a non-proportional relationship to the engine speed value during abnormal vibration. The accelerator pedal (3) is pressed down with a non-proportional relationship to the engine speed value during abnormal vibration as follows: n=k ′ (a+a t -a0) Wherein, α0 is the initial angle when the accelerator pedal (3) starts to respond, α is the angle when the accelerator pedal (3) is stepped on, n is the engine speed, α T is the angle corresponding to the skip speed, k ′ is a new proportional coefficient between the accelerator pedal (3) depression depth and the engine speed value at t≥t0.

2. The method for avoiding abnormal vibration speed in the non-working section according to claim 1 is characterized in that: The original state instruction is an instruction containing a positive proportional relationship between the accelerator pedal (3) depression depth and the engine speed value. Under normal circumstances, the positive proportional relationship between the accelerator pedal (3) depression depth and the engine speed value is: n=k(α-α0) Wherein, k is the proportional coefficient between the accelerator pedal (3) depression depth and the engine speed value.

3. The method for avoiding abnormal vibration speed in the non-working section according to claim 1 is characterized in that: The k ′ The value of is: Among them, n max is the maximum engine speed, n2 is the engine speed when the abnormal vibration ends, α max is the maximum angle of the accelerator pedal (3), and α2 is the angle of the accelerator pedal (3) when the abnormal vibration ends.

4. The method for avoiding abnormal vibration speed in the non-working section according to claim 3 is characterized in that: The α T The value of is: α T ＝α2-α1 Here, α1 is the angle of the accelerator pedal (3) when the abnormal vibration starts.

5. The method for avoiding abnormal vibration speed in a non-working section according to any one of claims 1 to 4, characterized in that: The value range of the abnormal vibration speed segment is [n1, n2], wherein n1 is the engine speed when the abnormal vibration starts, and n2 is the engine speed when the abnormal vibration ends.

6. The method for avoiding abnormal vibration speed in a non-working section according to any one of claims 1 to 4, characterized in that: The inclinometer (2) is mounted on the accelerator pedal (3).

Images