CN114813150A - Risk monitoring method, device and system for engine crankshaft bearing bush - Google Patents
Risk monitoring method, device and system for engine crankshaft bearing bush Download PDFInfo
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Abstract
The embodiment of the disclosure provides a method, a device and a system for monitoring risk of an engine crankshaft bush, wherein the method comprises the following steps: in the current cycle period, acquiring the current rotating speed of the engine, and determining whether the engine is in a resonance amplification state according to the current rotating speed; if the current resonance mode is in the resonance amplification state, judging the current resonance mode; obtaining the displacement of two sensors on a flywheel of the engine at the current rotating speed and the vibration mode Curve corresponding to the resonance mode of the current engine; the horizontal axis of the vibration mode Curve is the rotating speed of the engine, and the vertical axis is the amplitude ratio of the axle center of the last gear spindle to the axle center of the flywheel; determining the coordinate track of the axle center of the final gear spindle according to the displacement of two sensors on the flywheel at the current rotating speed and the vibration mode Curve; calculating the maximum eccentric amount of the axle center of the last gear spindle according to the coordinate track of the axle center of the last gear spindle; and if the maximum eccentricity exceeds a preset threshold value, tile-melting risk early warning is carried out, and tile-melting risk can be predicted.
Description
Technical Field
The embodiment of the disclosure relates to the technical field of engines, in particular to a method, a device and a system for monitoring risk of crankshaft bearing bush of an engine.
Background
The most serious reliability accident in the engine is the shaft-sticking bush, which means that the crankshaft of the engine and the bearing bush are stuck together, so that the engine cannot normally run.
The excessive bending vibration of the crankshaft is one of the important reasons for sticking the bearing bush, and therefore, a need is urgently needed for monitoring the gap between the crankshaft and the bearing bush and predicting the bearing bush risk caused by the bending vibration of the crankshaft in advance.
Disclosure of Invention
The embodiment of the disclosure provides a method, a device and a system for monitoring risk of bearing bush formation of an engine crankshaft, so as to monitor a gap between the crankshaft and a bearing bush and predict risk of bearing bush formation caused by bending vibration of the crankshaft in advance.
In a first aspect, an embodiment of the present disclosure provides an engine crankshaft bush risk monitoring method, including:
the method is applied to an electric control unit and comprises the following steps:
in the current cycle period, acquiring the current rotating speed of the engine, and determining whether the engine is in a resonance amplification state according to the current rotating speed;
if the engine is in a resonance amplification state, judging the current resonance mode according to the current rotating speed;
obtaining the displacement of two sensors on a flywheel of the engine at the current rotating speed and the vibration mode Curve corresponding to the resonance mode of the current engine; the horizontal axis of the vibration mode Curve is the rotating speed of the engine, and the vertical axis is the amplitude ratio of the axle center of the last gear spindle to the axle center of the flywheel;
determining a coordinate track of the axle center of the final gear spindle according to the displacement of the two sensors on the flywheel at the current rotating speed and the vibration mode Curve corresponding to the resonance mode of the current engine;
calculating the maximum eccentric amount of the axle center of the last gear spindle of the engine according to the coordinate track of the axle center of the last gear spindle;
and if the maximum eccentric amount of the axle center of the final gear spindle exceeds a preset threshold value, outputting an early warning signal of the cranked bearing bush of the engine.
In one possible design, the two displacement sensors include a first displacement sensor and a second displacement sensor, wherein the first displacement sensor measures a first amount of displacement and the second displacement sensor measures a second amount of displacement; correspondingly, the determining the coordinate track of the axle center of the final gear spindle according to the displacement of the two sensors on the flywheel at the current rotating speed and the vibration mode Curve corresponding to the resonance mode of the current engine includes: according to the current rotating speed, determining the amplitude ratio of the axle center of the last gear spindle corresponding to the current rotating speed to the axle center of the flywheel in the vibration mode Curve; multiplying the first displacement amount and the second displacement amount by the amplitude ratio of the axle center of the last gear spindle corresponding to the current rotating speed to the axle center of the flywheel respectively to obtain the eccentric amount of the axle center of the last gear spindle in the first direction and the eccentric amount of the last gear spindle in the second direction; and determining the eccentricity of the preset number of the collection points in the first direction and the eccentricity in the second direction as the coordinate track of the axle center of the final gear spindle.
In one possible design, after obtaining the current rotation speed of the engine and determining whether the engine is in the resonance amplification state according to the current rotation speed, the method further includes: if the engine is in a non-resonance amplification state, determining a coordinate track of the axle center of the flywheel according to the displacement of the two sensors on the flywheel at the current rotating speed; calculating the maximum eccentric amount of the flywheel axis of the engine according to the coordinate track of the flywheel axis; inquiring whether a non-zero value exists in the prestored maximum eccentricity MAP of the flywheel axle center according to the maximum eccentricity of the flywheel axle center; and if the non-zero value exists, making the maximum eccentricity of the axis of the flywheel and the non-zero value as a positive deviation percentage, and if the positive deviation percentage exceeds a preset limit value, outputting an engine crank bearing bush early warning signal.
In a possible design, after querying whether a non-zero value exists in the pre-stored maximum eccentricity MAP of the flywheel shaft center according to the maximum eccentricity of the flywheel shaft center, the method includes: and if the non-zero value does not exist, storing the maximum eccentricity of the flywheel axis into the pre-stored maximum eccentricity MAP of the flywheel axis, jumping to the current loop cycle again after one loop cycle period, acquiring the current rotating speed of the engine, and determining whether the engine is in a resonance amplification state according to the current rotating speed.
In one possible design, the resonance modes include a first order bending resonance mode and a second order bending resonance mode.
In a second aspect, an embodiment of the present disclosure provides an engine crankshaft bush risk monitoring device, including:
the first judgment module is used for acquiring the current rotating speed of the engine in the current loop cycle period and determining whether the engine is in a resonance amplification state according to the current rotating speed;
the second judgment module is used for judging the current resonance mode according to the current rotating speed if the engine is in a resonance amplification state;
the vibration mode processing module is used for acquiring the displacement of two sensors on a flywheel of the engine at the current rotating speed and the vibration mode Curve corresponding to the resonance mode of the current engine; the horizontal axis of the vibration mode Curve is the rotating speed of the engine, and the vertical axis is the amplitude ratio of the axle center of the last gear spindle to the axle center of the flywheel;
the first track processing module is used for determining a coordinate track of the axle center of the final gear spindle according to the displacement of the two sensors on the flywheel at the current rotating speed and the vibration mode Curve corresponding to the resonance mode of the current engine;
the first eccentricity calculation module is used for calculating the maximum eccentricity of the axle center of the final gear spindle of the engine according to the coordinate track of the axle center of the final gear spindle;
and the first early warning module is used for outputting an early warning signal of the cranked bush of the engine if the maximum eccentric amount of the axle center of the final gear spindle exceeds a preset threshold value.
In a third aspect, an embodiment of the present disclosure provides an electronic control unit, including: at least one processor and memory;
the memory stores computer execution instructions;
the at least one processor executing the computer-executable instructions stored by the memory causes the at least one processor to perform the engine crankshaft shoe risk monitoring method as set forth above in the first aspect and in various possible designs of the first aspect.
In a fourth aspect, an embodiment of the present disclosure provides an engine crankshaft lining risk monitoring system, including: the two displacement sensors are arranged on a flywheel of the engine, the two displacement sensors are positioned in the same section of the flywheel, and the radiuses from the two displacement sensors to the axis of the flywheel form a right angle; an electronic control unit for carrying out the engine cranked shoe risk monitoring method as described above in the first aspect and in various possible designs of the first aspect.
In a fifth aspect, embodiments of the present disclosure provide a computer-readable storage medium having stored thereon computer-executable instructions that, when executed by a processor, implement the engine cranked shoe risk monitoring method according to the first aspect and various possible designs of the first aspect.
In a sixth aspect, embodiments of the present disclosure provide a computer program product comprising a computer program which, when executed by a processor, implements the engine cranked shoe risk monitoring method according to the first aspect and various possible designs of the first aspect.
According to the method, the device and the system for monitoring the risk of the crankshaft bush of the engine, whether the engine is in a resonance amplification state or not is judged according to the current rotating speed of the engine; if the engine crankshaft is in a resonance amplification state, determining a vibration mode Curve corresponding to the resonance mode according to the resonance mode currently located, wherein the transverse axis of the vibration mode Curve is the rotating speed of the engine, the longitudinal axis is the amplitude ratio of the axis of a last gear spindle to the axis of a flywheel, the track of the axis of the last gear spindle is obtained according to the track of the axis of the last gear spindle and the vibration mode Curve determined by the displacement of two sensors on the flywheel at the current rotating speed of the engine, the maximum eccentric amount of the axis of the last gear spindle is obtained according to the track of the axis of the last gear spindle, whether the engine crankshaft has the risk of tile melting is judged according to the maximum eccentric amount of the axis of the last gear spindle, early warning is carried out, the monitoring of the crankshaft clearance of the engine is realized, the risk of tile melting caused by the bending vibration of the crankshaft is predicted, and the engine cannot normally run is ensured.
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In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present disclosure, and for those skilled in the art, other drawings can be obtained according to the drawings without inventive exercise.
FIG. 1 is a schematic view of a scenario of a method for monitoring risk of engine cranked bearing shoes according to an embodiment of the present disclosure;
FIG. 2 is a schematic flow chart of a method for monitoring risk of engine cranked shoes according to an embodiment of the present disclosure;
FIG. 3 is an exemplary illustration of a bending mode resonance of a crankshaft system of an inline four cylinder engine provided by an embodiment of the present disclosure;
FIG. 4 is a schematic structural diagram of an engine crankshaft bush risk monitoring device provided in an embodiment of the present disclosure;
fig. 5 is a schematic diagram of a hardware structure of an electronic control unit provided in the embodiment of the present disclosure.
Detailed Description
To make the objects, technical solutions and advantages of the embodiments of the present disclosure more clear, the technical solutions of the embodiments of the present disclosure will be described clearly and completely with reference to the drawings in the embodiments of the present disclosure, and it is obvious that the described embodiments are some, but not all embodiments of the present disclosure. All other embodiments, which can be derived by a person skilled in the art from the embodiments disclosed herein without making any creative effort, shall fall within the protection scope of the present disclosure.
The noun interpretation:
resonance: the system is subjected to a large amplitude vibrational response from an external excitation at a frequency that is the same as or very close to the natural frequency of the system.
MAP: the three-dimensional data map, for example, a coordinate a, b coordinate c, respectively represent different physical parameters, and the magnitude of the c coordinate is fixed under different a and b coordinates.
Curve: the two-dimensional data map, for example, the a and b coordinates represent different physical parameters respectively, and the magnitude of the b coordinate is fixed under different a coordinates.
The most serious reliability accident in the engine is the shaft-sticking bush, which means that the crankshaft of the engine and the bearing bush are stuck together, so that the engine cannot normally run. After the bearing bush is changed, the bearing bush is adhered to the crankshaft when the bearing bush is changed, and the bearing bush is extruded out from between the bearing bush cover and the crankshaft when the bearing bush is changed, so that the risks of bending and breaking of the crankshaft, deformation of a cylinder body and the like are caused, and even the engine is scrapped.
The reasons for the shoe are many, including insufficient supply of lubricating oil, loose connecting rod bolts, insufficient viscosity of engine oil, excessive bending vibration of the crankshaft, etc. The bending vibration of the crankshaft is an important reason, when the weight of the end of the flywheel is too heavy, the end of the flywheel can generate local bending vibration mode under the bending resonance of the crankshaft, so that the clearance of the bearing bush is reduced, and the crankshaft and the bearing bush are scratched to cause the bearing bush melting. Therefore, a method for monitoring the clearance between the crankshaft and the bearing bush and predicting the bearing bush risk in advance is needed.
In order to realize monitoring of a gap between a crankshaft and a bearing bush and prediction of a cranked bush risk, the embodiment of the disclosure provides an engine cranked bush risk monitoring method, the bearing bush risk state is set to a resonance amplification state and a non-resonance amplification state, different monitoring strategies are respectively adopted to predict the bush risk caused by crankshaft bending vibration, and the engine operation safety is improved.
Fig. 1 is a scene schematic diagram of an engine crankshaft bush risk monitoring method provided in an embodiment of the present disclosure. As shown in fig. 1, the scenario provided by the present embodiment includes: the device comprises an engine, a flywheel, an elastic coupling, a dynamometer, a gearbox, a generator set and the like. Taking a four-cylinder engine as an example, the engine comprises a crankshaft system, wherein the crankshaft system comprises a crankshaft belt pulley, one-cylinder to four-cylinder main journals and a flywheel.
The two displacement sensors are positioned in the same section of the flywheel, and the radiuses from the two displacement sensors to the axis of the flywheel form a right angle. The two displacement sensors are respectively in communication connection with the electric control unit, and the electric control unit obtains the displacement measured in the rotation process of the flywheel.
The electronic control unit can be any controller, such as a single chip microcomputer or a microcontroller. The displacement sensor may be any form of sensor, such as an eddy current displacement sensor.
Fig. 2 is a schematic flow chart of a method for monitoring risk of engine cranked bush according to an embodiment of the present disclosure, an execution main body of the embodiment may be an electronic control unit in the embodiment shown in fig. 1, and the electronic control unit may be any form of controller. As shown in fig. 2, the method includes:
s201: and in the current loop cycle period, acquiring the current rotating speed of the engine, and determining whether the engine is in a resonance amplification state according to the current rotating speed.
In the embodiment, whether the current rotating speed falls into the rotating speed interval range of the bending vibration resonance is judged according to the current rotating speed of the engine so as to determine whether the engine is in a resonance amplification state.
The range of the resonant rotating speed interval is obtained by calibrating according to different engines.
Wherein, the time Δ t of the loop cycle period can be set according to the requirement.
S202: and if the engine is in a resonance amplification state, judging the current resonance mode according to the current rotating speed.
In one embodiment of the present disclosure, the resonance modes include a first order bending resonance mode and a second order bending resonance mode.
Specifically, if the current rotating speed is within the range of the first rotating speed interval, determining that the current resonance mode is a first-order bending resonance mode; and if the current rotating speed is within a second rotating speed interval range, determining that the current resonance mode is a second-order bending vibration resonance mode, wherein the first rotating speed interval range is smaller than the second rotating speed interval range.
For example, taking a certain type of engine as an example, the first rotating speed interval range is 2000rpm to 2800 rpm; the second rotating speed interval ranges from 3700rpm to 4200 rpm.
Referring to fig. 3, fig. 3 is an exemplary illustration of a bending mode resonance of a crankshaft system of an inline four-cylinder engine provided by an embodiment of the present disclosure. In fig. 3, points 1 to 6 represent the concentrated mass models (or axis nodes) of the crank pulley, the one-to four-cylinder main journals, and the flywheel, respectively. Curve 1, which is the first-order bending vibration resonance mode; curve 2 is the second order bending resonance mode. The vibration amplitude ratio of the axes node vibration of the crankshaft belt pulley, the one-cylinder to four-cylinder main journal and the flywheel can be obtained through the vibration mode.
S203: obtaining the displacement of two sensors on a flywheel of the engine at the current rotating speed and the vibration mode Curve corresponding to the resonance mode of the current engine; the horizontal axis of the vibration mode Curve is the rotating speed of the engine, and the vertical axis is the amplitude ratio of the axle center of the last gear spindle to the axle center of the flywheel.
In the embodiment of the disclosure, according to the first-order bending vibration resonance mode, determining that the longitudinal axis at each rotation speed in the first rotation speed interval range is the amplitude ratio of the end gear spindle axis and the flywheel axis, so as to obtain the mode Curve.
S204: and determining the coordinate track of the axle center of the final gear spindle according to the displacement of the two sensors on the flywheel at the current rotating speed and the vibration mode Curve corresponding to the resonance mode of the current engine.
In one embodiment of the present disclosure, the two displacement sensors include a first displacement sensor and a second displacement sensor, wherein the first displacement sensor measures a first amount of displacement and the second displacement sensor measures a second amount of displacement; the horizontal axis of the vibration mode Curve is the rotating speed of the engine, and the vertical axis is the amplitude ratio of the axle center of the last gear spindle to the axle center of the flywheel;
correspondingly, the determining the coordinate trajectory of the axle center of the final gear spindle according to the displacement of the two sensors on the flywheel at the current rotating speed and the vibration mode Curve corresponding to the resonance mode where the current engine is located specifically includes:
according to the current rotating speed, determining the amplitude ratio of the axle center of the last gear spindle corresponding to the current rotating speed to the axle center of the flywheel in the vibration mode Curve; multiplying the first displacement amount and the second displacement amount by the amplitude ratio of the axle center of the last gear spindle corresponding to the current rotating speed to the axle center of the flywheel respectively to obtain the eccentric amount of the axle center of the last gear spindle in the first direction and the eccentric amount of the last gear spindle in the second direction; and determining the eccentricity of the preset number of the collection points in the first direction and the eccentricity in the second direction as the coordinate track of the axle center of the final gear spindle.
The preset number of collecting points can be set as required, for example, the preset number of collecting points n takes a value of 50.
In the embodiment of the present disclosure, the first displacement amount and the second displacement amount are respectively denoted as x and y, and the track coordinate of the flywheel axis may be denoted as (x, y). And (3) multiplying the first displacement x and the second displacement y by the amplitude ratio t of the axle center of the last gear spindle to the axle center of the flywheel respectively to obtain the eccentric quantity xt (marked as w) in the first direction and the eccentric quantity yt (marked as z) in the second direction, and then marking the coordinate track of the axle center of the last gear spindle as (w, z).
S205: and calculating the maximum eccentric amount of the axle center of the final gear spindle of the engine according to the coordinate track of the axle center of the final gear spindle.
In one embodiment of the present disclosure, the maximum eccentric amount of the last gear spindle axis of the engine is calculated according to the coordinate trajectory of the last gear spindle axis by using the following formula:
in the formula, i represents the number of collection points, and w and z are respectively the eccentric amount of the final gear spindle axis in the first direction and the eccentric amount of the final gear spindle axis in the second direction.
S206: and if the maximum eccentric amount of the axle center of the final gear spindle exceeds a preset threshold value, outputting an early warning signal of the cranked bearing bush of the engine.
In the disclosed embodiment, the preset threshold is determined according to the crankshaft and bearing bush clearance of different engines.
The output engine crankshaft tile early warning signal can be displayed on an instrument or a display screen, or can be broadcasted on voice equipment.
As can be seen from the description of the above embodiment, it is determined whether the engine is in a resonance amplification state according to the current rotation speed of the engine; if the engine crankshaft is in a resonance amplification state, determining a vibration mode Curve corresponding to the resonance mode according to the resonance mode currently located, wherein the transverse axis of the vibration mode Curve is the rotating speed of the engine, the longitudinal axis is the amplitude ratio of the axis of a last gear spindle to the axis of a flywheel, the track of the axis of the last gear spindle is obtained according to the track of the axis of the last gear spindle and the vibration mode Curve determined by the displacement of two sensors on the flywheel at the current rotating speed of the engine, the maximum eccentric amount of the axis of the last gear spindle is obtained according to the track of the axis of the last gear spindle, whether the engine crankshaft has the risk of tile melting is judged according to the maximum eccentric amount of the axis of the last gear spindle, early warning is carried out, the monitoring of the crankshaft clearance of the engine is realized, the risk of tile melting caused by the bending vibration of the crankshaft is predicted, and the engine cannot normally run is ensured.
In an embodiment of the present disclosure, after step S201, the method further includes:
s207: and if the engine is in a non-resonance amplification state, determining the coordinate track of the axle center of the flywheel according to the displacement of the two sensors on the flywheel at the current rotating speed.
In an embodiment of the present disclosure, the two displacement sensors include a first displacement sensor and a second displacement sensor, wherein the first displacement sensor measures a first displacement amount and the second displacement sensor measures a second displacement amount. Specifically, a first displacement quantity and a second displacement quantity of a preset number of acquisition points are determined as a coordinate track of the axis of the flywheel.
S208: and calculating the maximum eccentric amount of the flywheel axis of the engine according to the coordinate track of the flywheel axis.
In the embodiment of the present disclosure, the maximum eccentric amount of the flywheel axis of the engine is calculated according to the coordinate trajectory of the flywheel axis, and the formula is as follows:
in the formula, i represents the number of collection points, and x and y are respectively the first displacement and the second displacement measured by the two sensors.
S209: and inquiring whether a non-zero value exists in the prestored maximum eccentricity MAP of the flywheel axle center according to the maximum eccentricity of the flywheel axle center.
In the embodiment of the present disclosure, the non-zero value in the pre-stored maximum eccentricity MAP of the flywheel axis is the maximum eccentricity of the flywheel axis obtained in a previous cycle of the current cycle.
It should be noted that: when the detection strategy is initially applied, the value of the maximum eccentricity MAP of the axle center of the flywheel can be returned to zero.
S210: and if the non-zero value exists, making the maximum eccentricity of the axis of the flywheel and the non-zero value as a positive deviation percentage, and if the positive deviation percentage exceeds a preset limit value, outputting an engine crank bearing bush early warning signal.
In the embodiment of the present disclosure, the calculation formula of the positive deviation percentage between the maximum eccentricity of the flywheel axis and the non-zero value is as follows:
δ＝|(D i -D i-1 )/D i-1 |*100％
in the formula, Di is the maximum eccentricity of the flywheel axis obtained in the ith current cycle, that is, the maximum eccentricity of the flywheel axis in the current cycle.
In an embodiment of the present disclosure, if there is no nonzero value, storing the maximum eccentricity of the flywheel shaft center in the prestored maximum eccentricity MAP of the flywheel shaft center, and skipping again to the step of acquiring the current rotation speed of the engine after a loop cycle period, and determining whether the engine is in a resonance amplification state according to the current rotation speed.
From the above description, if the engine is in the non-resonance amplification state, the deviation of the maximum eccentric amount of the flywheel shaft center obtained in the adjacent cycle is calculated, and the degradation trend of the maximum eccentric amount of the flywheel shaft center is obtained, so as to judge whether the engine crankshaft has the tile-melting risk, and perform early warning.
Fig. 4 is a schematic structural diagram of an engine cranked bush risk monitoring device provided by the embodiment of the disclosure. As shown in fig. 4, in the engine crankshaft bush risk monitoring device 30, two displacement sensors are disposed on a flywheel of the engine, the two displacement sensors are located in the same cross section of the flywheel, and the radii from the two displacement sensors to the axis of the flywheel form a right angle, and the device is applied to an electronic control unit, and includes: the system comprises a first judgment module 301, a second judgment module 302, a vibration mode processing module 303, a first track processing module 304, a first eccentricity calculation module 305 and a first early warning module 306.
The first judgment module 301 is configured to acquire a current rotation speed of the engine in a current loop cycle period, and determine whether the engine is in a resonance amplification state according to the current rotation speed;
a second determining module 302, configured to determine a current resonance mode according to the current rotation speed if the engine is in a resonance amplification state;
the vibration mode processing module 303 is configured to obtain displacement amounts of two sensors on a flywheel of the engine at a current rotation speed, and a vibration mode Curve corresponding to a resonance mode where the current engine is located; the horizontal axis of the vibration mode Curve is the rotating speed of the engine, and the vertical axis is the amplitude ratio of the axle center of the last gear spindle to the axle center of the flywheel;
the first track processing module 304 is configured to determine a coordinate track of an axis of a top gear spindle according to the displacement amounts of the two sensors on the flywheel at the current rotation speed and a vibration mode Curve corresponding to a resonance mode where the current engine is located;
a first eccentricity calculation module 305, configured to calculate a maximum eccentricity of the axle center of the final gear spindle of the engine according to the coordinate trajectory of the axle center of the final gear spindle;
the first early warning module 306 is configured to output an engine cranked shoe early warning signal if the maximum eccentricity of the axle center of the last spindle exceeds a preset threshold.
The apparatus provided in this embodiment may be used to implement the technical solutions of the above method embodiments, and the implementation principles and technical effects are similar, which are not described herein again.
In one possible design, the two displacement sensors include a first displacement sensor and a second displacement sensor, wherein the first displacement sensor measures a first amount of displacement and the second displacement sensor measures a second amount of displacement; the trajectory processing module 304 is specifically configured to determine, according to the current rotation speed, an amplitude ratio between an axis of a last-gear spindle and an axis of a flywheel, which corresponds to the current rotation speed, in the vibration mode Curve; multiplying the first displacement amount and the second displacement amount by the amplitude ratio of the axle center of the last gear spindle corresponding to the current rotating speed to the axle center of the flywheel respectively to obtain the eccentric amount of the axle center of the last gear spindle in the first direction and the eccentric amount of the last gear spindle in the second direction; and determining the eccentricity of the preset number of the collection points in the first direction and the eccentricity in the second direction as the coordinate track of the axle center of the final gear spindle.
In one possible design, the engine cranked shoe risk monitoring device 30 further includes:
a second trajectory processing module 307, configured to determine a coordinate trajectory of an axis of the flywheel according to displacement amounts of the two sensors on the flywheel at the current rotation speed if the engine is in a non-resonance amplification state;
the second eccentricity calculation module 308 is configured to calculate a maximum eccentricity of the flywheel axis of the engine according to the coordinate trajectory of the flywheel axis;
a third judging module 309, configured to query whether a non-zero value exists in the pre-stored maximum eccentricity MAP of the flywheel axle center according to the maximum eccentricity of the flywheel axle center
The second warning module 310 is configured to, if a non-zero value exists, determine a positive deviation percentage between the maximum eccentric amount of the flywheel axis and the non-zero value, and if the positive deviation percentage exceeds a preset limit, output an engine cranked shoe warning signal.
In one possible design, the engine cranked shoe risk monitoring device 30 further includes:
and the value recording module 311 is configured to, if a nonzero value does not exist, store the maximum eccentricity of the flywheel axis into the pre-stored maximum eccentricity MAP of the flywheel axis, skip again to the step of acquiring the current rotation speed of the engine after a loop cycle period, and determine whether the engine is in a resonance amplification state according to the current rotation speed.
The apparatus provided in this embodiment may be used to implement the technical solutions of the above method embodiments, and the implementation principles and technical effects are similar, which are not described herein again.
Fig. 5 is a schematic diagram of a hardware structure of an electronic control unit provided in the embodiment of the present disclosure. As shown in fig. 5, the electronic control unit 40 of the present embodiment includes: a processor 401 and a memory 402; wherein
A memory 402 for storing computer-executable instructions;
the processor 401 is configured to execute the computer-executable instructions stored in the memory to implement the steps performed by the receiving device in the above embodiments. Reference may be made in particular to the description relating to the method embodiments described above.
Alternatively, the memory 402 may be separate or integrated with the processor 401.
When the memory 402 is provided separately, the electronic control unit further includes a bus 403 for connecting the memory 402 and the processor 401.
The embodiment of the disclosure also provides a computer-readable storage medium, in which a computer executing instruction is stored, and when a processor executes the computer executing instruction, the method for monitoring the risk of the crankshaft bush of the engine is implemented.
The embodiment of the present disclosure further provides an engine crankshaft tile risk monitoring system, including: the two displacement sensors are arranged on a flywheel of the engine, the two displacement sensors are positioned in the same section of the flywheel, and the radiuses from the two displacement sensors to the axis of the flywheel form a right angle; and the electronic control unit is used for executing the engine crankshaft bush risk monitoring method.
The displacement sensor may be any type of sensor, such as an eddy current displacement sensor.
Embodiments of the present disclosure also provide a computer program product comprising a computer program which, when executed by a processor, implements an engine crankcase risk monitoring method as described above.
In the several embodiments provided in the present disclosure, it should be understood that the disclosed apparatus and method may be implemented in other ways. For example, the above-described device embodiments are merely illustrative, and for example, the division of the modules is only one logical division, and other divisions may be realized in practice, for example, a plurality of modules may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed coupling or direct coupling or communication connection between each other may be through some interfaces, indirect coupling or communication connection between devices or modules, and may be in an electrical, mechanical or other form.
The modules described as separate parts may or may not be physically separate, and parts displayed as modules may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the modules may be selected according to actual needs to implement the solution of the present embodiment.
In addition, functional modules in the embodiments of the present disclosure may be integrated into one processing unit, or each module may exist alone physically, or two or more modules are integrated into one unit. The unit formed by the modules can be realized in a hardware form, and can also be realized in a form of hardware and a software functional unit.
The integrated module implemented in the form of a software functional module may be stored in a computer-readable storage medium. The software functional module is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device) or a processor to execute some steps of the methods described in the embodiments of the present application.
It should be understood that the Processor may be a Central Processing Unit (CPU), other general purpose Processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), etc. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like. The steps of a method disclosed in connection with the present invention may be embodied directly in a hardware processor, or in a combination of the hardware and software modules within the processor.
The memory may comprise a high-speed RAM memory, and may further comprise a non-volatile storage NVM, such as at least one disk memory, and may also be a usb disk, a removable hard disk, a read-only memory, a magnetic or optical disk, etc.
The bus may be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, an Extended ISA (EISA) bus, or the like. The bus may be divided into an address bus, a data bus, a control bus, etc. For ease of illustration, the buses in the figures of the present application are not limited to only one bus or one type of bus.
The storage medium may be implemented by any type or combination of volatile or non-volatile memory devices, such as Static Random Access Memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic or optical disks. A storage media may be any available media that can be accessed by a general purpose or special purpose computer.
An exemplary storage medium is coupled to the processor such the processor can read information from, and write information to, the storage medium. Of course, the storage medium may also be integral to the processor. The processor and the storage medium may reside in an Application Specific Integrated Circuits (ASIC). Of course, the processor and the storage medium may reside as discrete components in an electronic device or host device.
Those of ordinary skill in the art will understand that: all or a portion of the steps of implementing the above-described method embodiments may be performed by hardware associated with program instructions. The program may be stored in a computer-readable storage medium. When executed, the program performs steps comprising the method embodiments described above; and the aforementioned storage medium includes: various media that can store program codes, such as ROM, RAM, magnetic or optical disks.
Finally, it should be noted that: the above embodiments are only used for illustrating the technical solutions of the present disclosure, and not for limiting the same; while the present disclosure has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art will understand that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present disclosure.
Claims (10)
1. The method for monitoring the risk of the crank bush of the engine is characterized in that two displacement sensors are arranged on a flywheel of the engine, the two displacement sensors are positioned in the same section of the flywheel, and the radiuses from the two displacement sensors to the axle center of the flywheel form a right angle with each other, and the method is applied to an electric control unit and comprises the following steps:
in the current cycle period, acquiring the current rotating speed of the engine, and determining whether the engine is in a resonance amplification state according to the current rotating speed;
if the engine is in a resonance amplification state, judging the current resonance mode according to the current rotating speed;
obtaining the displacement of two sensors on a flywheel of the engine at the current rotating speed and the vibration mode Curve corresponding to the resonance mode of the current engine; the horizontal axis of the vibration mode Curve is the rotating speed of the engine, and the vertical axis is the amplitude ratio of the axle center of the last gear spindle to the axle center of the flywheel;
determining a coordinate track of the axle center of the final gear spindle according to the displacement of the two sensors on the flywheel at the current rotating speed and the vibration mode Curve corresponding to the resonance mode of the current engine;
calculating the maximum eccentric amount of the axle center of the last gear spindle of the engine according to the coordinate track of the axle center of the last gear spindle;
and if the maximum eccentric amount of the axle center of the final gear spindle exceeds a preset threshold value, outputting an early warning signal of the cranked bearing bush of the engine.
2. The method of claim 1, wherein the two displacement sensors comprise a first displacement sensor and a second displacement sensor, wherein the first displacement sensor measures a first amount of displacement and the second displacement sensor measures a second amount of displacement;
correspondingly, the determining the coordinate track of the axle center of the final gear spindle according to the displacement of the two sensors on the flywheel at the current rotating speed and the vibration mode Curve corresponding to the resonance mode of the current engine includes:
according to the current rotating speed, determining the amplitude ratio of the axle center of the last gear spindle corresponding to the current rotating speed to the axle center of the flywheel in the vibration mode Curve;
multiplying the first displacement amount and the second displacement amount by the amplitude ratio of the axle center of the last gear spindle corresponding to the current rotating speed to the axle center of the flywheel respectively to obtain the eccentric amount of the axle center of the last gear spindle in the first direction and the eccentric amount of the last gear spindle in the second direction;
and determining the eccentricity of the preset number of the collection points in the first direction and the eccentricity in the second direction as the coordinate track of the axle center of the final gear spindle.
3. The method of claim 1, wherein after obtaining a current speed of the engine and determining whether the engine is in the resonance amplification state based on the current speed, further comprising:
if the engine is in a non-resonance amplification state, determining a coordinate track of the axle center of the flywheel according to the displacement of the two sensors on the flywheel at the current rotating speed;
calculating the maximum eccentric amount of the flywheel axis of the engine according to the coordinate track of the flywheel axis;
inquiring whether a non-zero value exists in the prestored maximum eccentricity MAP of the flywheel axle center according to the maximum eccentricity of the flywheel axle center;
and if the non-zero value exists, making the maximum eccentricity of the axis of the flywheel and the non-zero value as a positive deviation percentage, and if the positive deviation percentage exceeds a preset limit value, outputting an engine crank bearing bush early warning signal.
4. The method according to claim 3, wherein after inquiring whether the pre-stored maximum eccentricity MAP of the flywheel axle center has a non-zero value according to the maximum eccentricity of the flywheel axle center, the method comprises:
and if the non-zero value does not exist, storing the maximum eccentricity of the flywheel axis into the pre-stored maximum eccentricity MAP of the flywheel axis, jumping to the current loop cycle again after one loop cycle period, acquiring the current rotating speed of the engine, and determining whether the engine is in a resonance amplification state according to the current rotating speed.
5. The method according to any one of claims 1 to 4, wherein the resonance modes include a first order bending mode resonance and a second order bending mode resonance.
6. An engine cranked shoe risk monitoring device, comprising:
the first judgment module is used for acquiring the current rotating speed of the engine in the current loop cycle period and determining whether the engine is in a resonance amplification state according to the current rotating speed;
the second judgment module is used for judging the current resonance mode according to the current rotating speed if the engine is in a resonance amplification state;
the vibration mode processing module is used for acquiring the displacement of two sensors on a flywheel of the engine at the current rotating speed and the vibration mode Curve corresponding to the resonance mode of the current engine; the horizontal axis of the vibration mode Curve is the rotating speed of the engine, and the vertical axis is the amplitude ratio of the axle center of the last gear spindle to the axle center of the flywheel;
the first track processing module is used for determining a coordinate track of the axle center of the final gear spindle according to the displacement of the two sensors on the flywheel at the current rotating speed and the vibration mode Curve corresponding to the resonance mode of the current engine;
the first eccentricity calculation module is used for calculating the maximum eccentricity of the axle center of the final gear spindle of the engine according to the coordinate track of the axle center of the final gear spindle;
and the first early warning module is used for outputting an early warning signal of the crank bearing bush of the engine if the maximum eccentricity of the axle center of the last gear spindle exceeds a preset threshold value.
7. An electronic control unit, comprising: at least one processor and memory;
the memory stores computer-executable instructions;
the at least one processor executing the computer-executable instructions stored by the memory causes the at least one processor to perform the engine cranked shoe risk monitoring method according to any one of claims 1 to 5.
8. An engine cranked shoe risk monitoring system, comprising:
the two displacement sensors are arranged on a flywheel of the engine, the two displacement sensors are positioned in the same section of the flywheel, and the radiuses from the two displacement sensors to the axis of the flywheel form a right angle;
an electronic control unit for performing the engine cranked shoe risk monitoring method according to any one of claims 1 to 5.
9. A computer readable storage medium having computer executable instructions stored thereon which, when executed by a processor, implement the engine cranked shoe risk monitoring method according to any one of claims 1 to 5.
10. A computer program product comprising a computer program, wherein the computer program when executed by a processor implements the engine cranked shoe risk monitoring method of any one of claims 1 to 5.
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